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At present, there are many problems existing in our chemical industry. For example, the equipment is too large; energy consumption is too much; environmental pollution is very serious; operating efficiency is relatively low. It has been a great challenge for researchers to solve all these problems. Fortunately, the successful development and application of micro-chemical technology has the probability to change present situation. Micro-chemical technology can change the property, size, consumption amount of present chemical equipment. There are many exothermic processes with strong reactions in chemical industry. These processes have great danger of explosion. The application of micro-reaction technology can raise the operation efficiency and improve the safety during the process.

The constant renewal of information technology characterized by computers and the development of Micro-electromechanical Systems put the concept of “micromation” into people’s jobs and daily life. After two development stages of unit operation and momentum transport, energy transport, quality transport and reaction engineering, chemical engineering science has gradually expanded to microscale field.

It is said that micro-chemical engineering and technology integrate the ideas of Micro-electromechanical Systems with basic principles of chemistry and chemical industry together and mainly study the basic characteristics and rules of the process of design, imitation, production and application of micro-model equipment in chemical industry when the space-time scale is under a few hundred microns and microseconds. Compared with conventional chemical equipment, micro-chemical equipment has many better properties of high transmission rate, high security and easy control, which can realize the constant operation and high integrative and flexible production. In addition, micro-reactive technology has great ability of heat and mass transmission, which can increase efficiency of resources and energy utilization in various reaction processes. Thus, the intensification, miniaturization and greening of chemical processes can be realized.

Because of the miniaturization of feature scale, the development of micro-chemical technology not only creates a great challenge in technology field, but also raises many new problems in the field of science. In the chemical system of micro-scale, the theories of the traditional momentum transport, energy transport, quality transport and reaction engineering need to be innovated. In addition, many macro rules may be not suitable any more. Therefore, the basic studies on things like surface effect and interface effect under micro-scale are more important. At present, the studies of micro-reaction system mainly focus on fields like production process, energy and environment, drug development and biological technology, etc.

Actually, micro-reaction technology has attracted developed countries like America since the beginning of 1990s. Many countries have made research plans one after another to advance the utilization process of “micro-reaction technology”. Many institutes have already begun their research on micro-reaction technology, such as Dalian Institute of Chemical Physics. In 2000, researchers in Dalian Institute of Chemical Physics took the lead in doing such research in our country. Now a complete research and development system has formed integrating technology platform of micromachining with the basic study and application of micro-chemical engineering and technology.

It is estimated that micro-chemical technology will be applied successfully to present equipment upgrading, the integration of micro-reaction device and equipment in conventional process, micro hydrogen resources system and personal products in approaching five to ten years.

Science is a concept of doing work relentlessly and looking for unseen and unnoticed which befitted with a natural tendency of a child who wants to do experiment with his own hands and see results to analyze an outcome of the experiment. Each child has tendency to run for new objects, tries to touch and pick up. Such experiments do induce a confidence in the child. The science is 100% experimental art of living, for example, the child watches and catches the object which comes before his eyes. It seems that more the child watches and catches more the child gains confidence to do more and more with many things provided objects are visible.

An art of catching needs a skill to go near object which acts as goal and mission to the child. There are different kinds of the toys being made with several options of touching and operation and playing. Such regular activities become an open laboratory to child. Thus a concept of toys was introduced and is contributing a lot to child growth and fixing goals in the lab. As the laboratory teaches science and reveal many unnoticed and unknown mysteries of knowledge and nature. Similarly the toy playing with wider options contribute to groom child’s personality. Some toys have attractive colors which introduce a concept of color and the child learns the color science. Noticeably, somewhere, the toys have most attractive and fascinating size and shape that teaches sense of the size and shape of the object which is interesting part of the geometry. Currently most of the toys are fitted with electronic devices which run either by solar or chemical cells and inculcate a sense of electrochemistry and the current.  The child understands that a solid object called cell can run a toys, the child also comes to learn the meaning of current.  

Truly, the child is a human unit. if every unit of  structure is perfectly shaped up then  no fixtures and fissions will be noticed in sustainment and functioning of the building.  The nation is like a building with so many interlocking units between so many independent ideas and objects as well.   The early stage of the child is most sensitive as initially, nothing is printed in mind and is like a clean slat or a clean page. The child does not have interfacing of the outside world and hence is dean nor have any seed to grow.  The new born child after 2/4 months starts interfacing with the outside world, his eyes see different kinds of the objects which give different kinds of impulses and reflections back to child minds. Thus, the eyes are vital weapon to interconnect the growing child with outside world. This is a first interfacing and interaction organ. Unfortunately, such impulse and reflections are missing in case of the visually challenged children.

The child interaction and interfacing (CII) towards outside worlds become learning and sensing laboratory. With time the child becomes more curious to ensure an existence of the object as the child does not see abstract objects. So the child is greatest scientist because he wants to do experiment with its own hands. There is a general observation in majority of children that within 1 to 4 years, the child put its hands on each and everything. His valuable efforts are to ensure the objectivity of the subject. The subject may be color, liquid, tree, cattle, animals, snake, insect, machine, explosive etc. and objects of any shape and size, power and granules.  It is so as the child’s initial sense is to gain maximum information by doing experiment. The child does not believe in 2nd hand information, data, regression data or secondary data generation along permutations and combinations. The child wants to do verification of everything and gains information to make a pool of information in the mind. Thus, the child is a greatest or extraordinary scientist. The faculties of the child grow with indefinite experiments in daily life. The child is also following perfect laws of thermodynamics by putting his whole body in motion. The 2 to 3 months child can’t work and keeps vibrating his hands and legs.

Currently different kinds of toys which give sounds, light and movements are available thus the child learns a lot about the physics. Similarly in on several occasion of public fairs, the toys man or the man who sales the toys has different kinds of the springs run toys. Through a spring mechanism, the toys are launched towards sky against gravity and flashes light of different colors. As these are scientific experiments to children who are very craggy to do such experiment? The child has greatest crag or fire to do such experiments. Such fire and crag makes to do more and more experiments and learning which is very true that “craggy can climb the heights of success”. Similarly during public fairs or gatherings, the liquids are spreaded in air with help of small pressure applied on the liquids.

The pressure makes rings of different sizes that reflect different color. Apart from theses, there are electronic toys which are expense due to electronic components. The liquids used with the toys have lower surface tension and viscosity, and develop rings on exposing to open air. The liquids quickly get spreaded as thin film to form rings. Similarly, on the occasion of Hindu festival Dewali and Holi, the children come to know about chemicals and explain color chemicals which give a lot of exposure of chemistry. The survismeter analyze the surface tension and viscosity together, and is current invention emerged out of a research work of Indian scientist. Many trials could be made to spread liquid as thin films to develop rings. This kind of learning is noted as “Learning in Fun”.

Visually Challenged: Agony of an absence of knowledge with suitable technology is in case of the visually challenged people who do not have proper vision and are victimized in absence of vision. Unfortunately, in case of the visually challenged, there no technology to substitute and encourage for interfacing and interaction with outside world. Thus, an impasse is there with them and a horrible situation arises in case of visually challenged children who need support of the society to be as their eyes to activate functional interfacing and interacting. Their body could be very operational and a kind of exercise could be developed to activate them. In case of them, the sounds become an important medium to interface and to interact with the outside world. Sometimes, a growing visually challenged child becomes a liability on parents and the society. This is an unfortunate situation due to handicapcy of human own limitations.

Since no attempts are made to develop suitable technology to boost up their interfacing. In general, there is an urgent need to strengthen and to widen and compensate their challenge. The sound could be another important sense to assist and to blossom their growth. The sound is converted with highly sensitive frequency waves as the frequencies are commercially used worldwide. The radio, the violin, mobile phones, the message sent through specified frequencies. The sound like harmonium, flute, bond, music is indispensable of the human being and human history. The sound is made of frequencies; it is energy moves in form of wave front. Visually challenged could be trained to do sound related works. Currently, Visionmeter is noted as a remarkable contribution in the field of science and technology to support the living and open wider options of the employments to them to make their life highly equal to sighted people.

 

 

 

Contents

The show ran about the same time as and covered similar topics to Beakman’s World, in fact sharing one crew member, editor/writer/director Michael Gross. He made an appearance on the Disney Channel’s New Mickey Mouse Club in its forty-eighth episode Anything Can Happen Day. Before this show, Bill Nye had previously worked alongside Christopher Lloyd in Back to the Future: The Animated Series, where Nye played Doc Brown’s assistant and demonstrated several experiments.

Bill Nye the Science Guy has been likened to a modern Mr. Wizard. Bill’s TV persona is a tall and slender scientist wearing a lab coat and a bow-tie. He mixes the serious science of everyday things with fast-paced action and humor. Each show begins with Bill walking onto the set, called “Nye Labs”, which is filled with scientific visuals (including many “of science” contraptions announced dramatically, such as “The slingshots of Science!”) relevant to the topic of the show. Most episodes contain a mock song parody and music video in the “Soundtrack of Science” by “Not That Bad Records”, substituting a scientific roundup of the episode for the lyrics to a popular song. Each show ends with Bill explaining his departure in a clever description of an activity on topic. The credits sometimes rolled next to a series of outtakes from the episode. Other times, outtakes are shown at the time they actually happened.

Another popular member of the cast is the announcer Pat Cashman, whom Nye knew from his time on Almost Live!. Some announcers who subbed in for Cashman include Ernie Anderson, Gary Owens, and Brian Cummings. In 1996, Bill made a guest appearance on Cartoon Network’s talk-show Space Ghost Coast to Coast in its twenty-fourth episode, Boo! with Michael Norman. A year later, he made a guest appearance on the long-running PBS series Mister Rogers’ Neighborhood.

List of episodes

Episodes

Season

Episode number

Episode name

“Soundtrack of Science” Parody song

1

1

Flight

Nyevana – “Smells Like Air Pressure”

Parody of “Smells Like Teen Spirit” by Nirvana

2

Earth’s Crust

Magmadonna – “Crust”

Parody of “Vogue” by Madonna

3

Dinosaurs

J.C. – “Mr. Dino”

Parody of “Mr. Wendal” by Arrested Development

4

Skin

No music video

5

Buoyancy

Sure Floats-alot – “Bill’s Got Boat”

Parody of “Baby Got Back” by Sir Mix-a-Lot

6

Gravity

Attraction Action – “G-R-A-V-I-T-Y”

Parody of “Twilight Zone” by 2 Unlimited

7

Digestion

Dy Gestion – “Can’t Eat This”

Parody of “Can’t Truss It” by Public Enemy

8

Phases of Matter

Phaze Change – “Solid Liquid Gas”

Parody of “Rebirth of Slick (Cool Like Dat)” by Digable Planets

9

Biodiversity

Bio Di Versity – “We’re all Connected”

Parody of “Connected” by Stereo MC’s

10

Simple Machines

The Pulley Ramp Five – “ABC’s of Machinery”

Parody of “ABC” by The Jackson 5

11

The Moon

The Lunatics – “Moon Cycle”

Parody of “Bicycle Race” by Queen

12

Sound

Gloria Wavelength and the Vibrations – “Sound is a VIBE”

Parody of “I Will Survive” by Gloria Gaynor

13

Garbage

Trash E. Trash – “R.E.C.Y.C.L.E.”

Parody of “Respect” by Aretha Franklin

14

Structure

Stress N’ Tension – “Let’s Talk About Stress”

Parody of “Let’s Talk About Sex” by Salt-n-Pepa

15

Earth’s Seasons

A Tilted Development – “Rhyme and Season”

16

Light & Color

The Bent Wavelengths – “Light and Colour”

Parody of “Trust and Dread and the Fugitive Mind” by Megadeth

17

Cells

Mighty Chondria – “Cellular Haze”

Parody of “Purple Haze” by Jimi Hendrix

18

Electrical Current

Billy Ray Cyrcuits – “AC/DC Charge”

Parody of “Achy Breaky Heart” by Billy Ray Cyrus

19

Outer Space

Elve Centuri – “Celestial Hotel”

Parody of “Heartbreak Hotel” by Elvis Presley

20

Eyeball

The Eye Doctors – “Two Eyes”

Parody of “Two Princes” by The Spin Doctors

2

21

Magnetism

N.S. Cool J. – “Opposites Attract”

Parody of “Insane in the Brain” by Cypress Hill

22

Wind

Wind Dee – “Wind Is In Your Hair”

Parody of “Groove Is In The Heart” by Deee-Lite

23

Blood and Circulation

AB+ – “Blood Stream”

Parody of “Love Shack” by The B-52’s

24

Chemical Reactions

Chemical Reactions – “Don’t Try This at Home”

Parody of “State of Attraction” by Paula Abdul

25

Static Electricity

The Sticky Socks – “Static Electricity”

Parody of “Turning Japanese” by The Vapors

26

Food Web

Food Webby Web – “(It’s The) Food Web”

Parody of “Who Am I (What’s My Name)?” by Snoop Dogg

27

Light Optics

Queen Lighteefa – “B.E.N.T.”

Parody of “U.N.I.T.Y.” by Queen Latifah

28

Bones and Muscles

Steppenbone – “Bones in my Body”

Parody of “Born to be Wild” by Steppenwolf

29

Oceanography

Gulfstream Girls – “Deep Ocean Currents”

Parody of “California Girls” by The Beach Boys

30

Heat

LeHot – “LeHeat”

Parody of “Le Freak” by Chic

31

Insects

UB Buggy – “Jah Mon, Insects Rule”

Style Parody of UB40

32

Balance

Torquer – “Balance This”

Parody of “Get Off This” by Cracker

33

The Sun

Deep Yellow – “My Favorite Star”

Parody of “Highway Star” by Deep Purple

34

Brain

En Lobe – “Whatta Brain”

Parody of “Whatta Man” by En Vogue with Salt-n-Pepa

35

Forests

John Cougar Loggincamp – “Second Growth”

Style Parody of John Mellencamp

36

Communication

Mary Chapin Communicator – “How Can We Communicate”

Parody of “He Thinks He’ll Keep Her” by Mary Chapin Carpenter

37

Momentum

Momentisey – “The Faster You Push Me”

Parody of “The More You Ignore Me, the Closer I Get” by Morrissey

38

Reptiles

No music video – the commercial-free PBS version of the episode, however, had a brief spoof entitled “Cold Blooded”.

Parody of “Hot Blooded” by Foreigner

39

Atmosphere

Warm -n- Wetta – “Fresh Aire”

40

Respiration

Ali Veoli – “What A Pair”

Style Parody of Tatyana Ali

3

41

The Planets

No music video

42

Pressure

PSI Garden – “Pressure”

Parody of “Spoonman” by Soundgarden

43

Plants

Rhoda Dendron – “Cross Pollination”

Parody of “Human Behaviour” by Bjrk

44

Rocks and Soil

Sedimentary Fools – “Rocks Rock Harder”

45

Energy

The ERG’s – “N-R-G”

Style Parody of the Beastie Boys

46

Evolution

Evolver – “Survival”

Style Parody of Veruca Salt

47

Water Cycle

J.A.C. – “Water Cycle Jump”

Parody of “Jump” by Kris Kross

48

Friction

Grace Slip – “Friction Happens”

49

Germs

Dose of Soap – “Just Wash Your Hands”

Parody of “Don’t Turn Around” by Ace of Base

50

Climates

Climate Report – “Whether the Weather”

Parody of “Lucas With The Lid Off” by Lucas Secon

51

Waves

Big Amplitude – “Baby I Love Your Wave”

Parody of “Baby, I Love Your Way” by Big Mountain (originally by Peter Frampton)

52

Ocean Life

James Baleen – “Power To The Plankton”

Style Parody of James Brown

53

Mammals

Fake Fur – “Jennifer’s A Mammal”

Parody of “Institutionalized” by Suicidal Tendencies

54

Spinning Things

House of Spin – “Spin Around”

Parody of “Jump Around” by House of Pain

55

Fish

Salmon Dave – “I’m a Sole Man”

Parody of “Soul Man” by Sam & Dave

56

Human Transportation

Carpoolio – “Move Groove”

Parody of “Fantastic Voyage” by Coolio

57

Wetlands

Maria and the Mudflaps – “Where The Land is Wet”

58

Birds

LL Bloo J. – “Talkin’ Bout Birds”

59

Populations

Shirell Crow – “All We Need To Do”

Parody of “All I Wanna Do” by Sheryl Crow

60

Animal Locomotion

Bjorn Turun – “Loco Motion”

Parody of “Everything Zen” by Bush

4

61

Rivers and Streams

Talking Headwaters – “Take Me To The River”

Parody of “Take Me To The River” by Talking Heads

62

Nutrition

Knute Trishan – “Good Food”

63

Marine Mammals

Marina Cesealia – “Breathe Like Me”

Parody of “I Know” by Dionne Farris

64

Earthquakes

Mistah Richter – “Earthquake Rumble”

65

NTV Top 11 Video Countdown

Mudhoney – “Bill Nye The Science Guy Theme”

66

Spiders

Foo Spighters – “This is A Spiders Life”

Parody of “This Is a Call” by Foo Fighters

67

Pollution Solutions

No music video

68

Probability

Steven Odd – “50 Fifty”

Parody of “Loser” by Beck

69

Pseudoscience

Dare L. Pseudo – “Pure Proof”

Parody of “100% Pure Love” by Crystal Waters

70

Flowers

Daisy Birdsenbees – “So Many Flowers”

71

Archaeology

Mob Barley – “Diggin’”

Parody of “Jamming” by Bob Marley

72

Deserts

Deserette – “Always Dry”

Parody of “You Oughta Know” by Alanis Morissette

73

Amphibians

P-Swamp All Stars with DJ Hoppy – “The Amphidelic Mothership Metamorphisis”

Style Parody of George Clinton the P-Funk All Stars

74

Volcanoes

Volcanque – “Lavaflows”

Parody of “Waterfalls” by TLC

75

Invertebrates

S. Khar Go – “Crawl Away”

Parody of “Runaway” by Janet Jackson

76

Heart

Vinny Vein and the Pumpers – “Gimme Back My Heart”

77

Inventions

En Vent and the Process – “It’s An ‘ing Thing”

78

Computers

La Binary – “One Zero 001″

Parody of “Be My Lover” by La Bouche

79

Fossils

Etchton Stone – “Fossil Man”

Parody of “Rocket Man” by Elton John

80

Time

The Tim E. Zone Experience – “Time Time Time Time Time…”

Parody of “Time Has Come Today” by The Chambers Brothers

5

81

Forensics

Krime Seen – “We Will Find You”

Parody of “We Will Rock You/We Are the Champions” by Queen

82

Space Exploration

The Space Princess of Galactic Grooviness – “Planets All”

Parody of “Set You Free” by Planet Soul

83

Genes

Alice in Genes – “It’s Called Genetics”

Parody of “Killing in the Name” by Rage Against the Machine’

84

Architecture

The Artist Formerly Known as Archie T. – “Makin’ Plans”

Parody of “All Mixed Up” by 311

85

Farming

Chris Ballew – “Farm Food”

Parody of “Peaches” by The Presidents of the United States of America, of which Ballew himself is a member

86

Life Cycle

Roberta Fungi – “Everything Has A Life Cycle”

Parody of “Killing Me Softly” by Roberta Flack

87

Do-It-Yourself Science

Nye & The Family Crust – “Do It Yourself Science”

Parody of “Hell” by Squirrel Nut Zippers

88

Atoms and Molecules

Third Nye Blind – “Atoms in My Life”

Parody of “Semi Charmed Life” by Third Eye Blind

89

Ocean Exploration

The Posies “Voyage of the Aquanauts”

90

Lakes and Ponds

The Foggy Boyz – “Found of Lakes and Ponds”

Parody of “Tha Crossroads” by Bone Thugs-n-Harmony

91

Smell

Turbinator Two – “Come On Use Your Brain (Smell This)”

Parody of “C’mon N’ Ride It (The Train)” by Quad City DJ’s

92

Caves

Batilda & Guano – “Cave Thing”

Parody of “Shake Your Groove Thing” by Peaches & Herb

93

Fluids

Weflo – “Drip it”

Parody of “Whip It” by Devo

94

Erosion

Earth, Wind & Ice – “Causing the Erosion”

Style Parody of No Doubt

95

Comets and Meteors

Halley Comet – “Got Me Looking”

Parody of “Shadowboxer” by Fiona Apple

96

Storms

Mighty Might Thundertones – “Stormin’”

Style Parody of Reel Big Fish

97

Measurement

The Meter Men – “Every Measurement You Make”

Parody of “Every Breath You Take” by The Police

98

Patterns

Downward Spiral – “Patterns of Joy”

Style Parody of The Prodigy

99

Music

“There’s Science In Music”

Parody of “The Time Warp” by Richard O’Brien

100

Motion

Slow Moe – “All in Motion”

Style Parody of Van Halen

Theme song

Aside from Bill himself, one of the most memorable things about Bill Nye the Science Guy is its theme song. The bass-heavy theme is set to a Hip hop beat with Bill’s name shouted throughout the duration of the song. The sound and speed fluctuations of the voice were accomplished through a vocoder and electronic pitch fluctuator. The theme song is credited to Mike Greene.

Production music

The show’s episodes consisted of several compositions from Associated Production Music, some featured tracks include:

“Act of Heroism (c)

“Blood in the Gutter” by Laurie Johnson

“Drama Impact #3″

“The Gunfighter” by Ennio Morricone

“Hit and Run” by Ralph Dollimore

“Killer Birds” by Gregor Narholz

“Saw Theme”

Many of these tracks were also featured in many Nickelodeon cartoons in the 1990s. Another common track used was the theme from the English show Dave Allen At Large, here used as the theme from “The Jackie Smazz Show.”

Funding

National Science Foundation (1993-1997)

Alfred P. Sloan Foundation (1993-1997)

The Boeing Company (1993-1997)

Ore-Ida (1996-1997)

Intel (1995-1997)

Corporation for Public Broadcasting (1993-1997)

Viewers Like You (1993-1997)

Video Game

A computer game for the series, titled Bill Nye the Science Guy: Stop the Rock!, was released in 1996 for PC and Macintosh by Pacific Interactive. In the game, a large meteoroid called “Impending Dum” threatens to make a catastrophic collision with the Earth. A team of scientists develop a laser satellite-controlling computer system called MAXX to destroy the meteoroid; however, MAXX develops a personality of its own (in an obvious parody of the sentient computer HAL from the film and novel 2001: A Space Odyssey) and refuses to save the planet unless Earth’s scientists can solve seven science riddles. Nye Labs decides to take on MAXX’s challenge, and the player, depicted as the newest member of the Nye Labs team, is asked to solve these riddles before Impending Dum hits (represented through an in-game timer). The game featured a fully explorable Nye Labs, as well as video cut scenes featuring Bill Nye and other Nye Labs scientists. However, the characters and cast members from the TV series, sans Bill Nye and a few others, do not appear in this game, instead being replaced by game-exclusive Nye Labs team members and new actors.

References

^ http://www.imdb.com/name/nm0343449/

See also

Bill Nye

The Eyes of Nye

Almost Live!

Universe of Energy – an attraction at Walt Disney World’s EPCOT Center starring Bill Nye.

Stuff Happens (TV show)

External links

Bill Nye, the Science Guy at the Internet Movie Database

Bill Nye the Science Guy at TV.com

Bill Nye, The Science Lab Official Site (billnye.com points to the same site)

v  d  e

PBS Kids shows

Current shows

Angelina Ballerina   Barney & Friends   Betsy’s Kindergarten Adventures   Between the Lions   Bob the Builder   Caillou   Curious George   Dinosaur Train   Franny’s Feet   It’s a Big Big World   Mama Mirabelle’s Home Movies   Martha Speaks   Sesame Street   Super Why!   Sid the Science Kid   Thomas and Friends   WordWorld

PBS Kids GO!

Arthur   Cyberchase   DragonflyTV   Design Squad   The Electric Company (2009)   FETCH! with Ruff Ruffman   Maya & Miguel   Postcards from Buster   WordGirl

Past shows

3-2-1 Contact   Adventures from the Book of Virtues   The Adventures of Dudley the Dragon   The Berenstain Bears (2003) *  Bill Nye the Science Guy   The Big Comfy Couch   Boohbah   Captain Kangaroo   Charlie Horse Music Pizza   Clifford the Big Red Dog *  Clifford’s Puppy Days *  Dragon Tales *  The Electric Company (19711977)   Gerbert   George Shrinks   Ghostwriter (19921995)   The Huggabug Club   In the Mix   Jakers! The Adventures of Piggley Winks   Jay Jay: The Jet Plane *  Katie and Orbie   Kidsongs   Kratts’ Creatures   Lamb Chop’s Play-Along   Liberty’s Kids   Long Ago & Far Away   The Magic School Bus ?  Mark Kistler’s Imagination Station   Mister Rogers’ Neighborhood *  Newton’s Apple   Noddy   Pappyland   PBS Kids Bookworm Bunch   Peep and the Big Wide World?   Powerhouse   The Puzzle Place   Reading Rainbow*   Sagwa, the Chinese Siamese Cat *  Shining Time Station   Square One Television   Seven Little Monsters   Teletubbies   Theodore Tugboat   Tots TV   Where in the World is Carmen Sandiego?   Where in Time is Carmen Sandiego?   Wimzie’s House   Wishbone *  Zoboomafoo *  Zoobilee Zoo   ZOOM *

Note

This list does not include shows from networks airing PBS Kids shows that are not funded directly by PBS, such as shows created by and funded by local PBS affiliates.

See also

PBS network shows   Educational television

* = No new episodes are being produced; reruns still airing on many major PBS stations or on PBS Kids Sprout.

= Not distributed via PBS, but by American Public Television.

= Airing (as of 2010[update]) on Qubo Channel.

? = Airing (as of 2010[update]) on Discovery Kids.

= Airing (as of 2010[update]) on This TV.

= Airing (as of 2010[update]) on Smile of a Child TV.

Categories: PBS network shows | 1990s American television series | Science education television series | American comedy television series | CBS network shows | Disney Channel shows | Television series by Buena Vista Television | 1993 television series debuts | 1997 television series endings | Television spin-offsHidden categories: Articles needing additional references from February 2010 | All articles needing additional references | Articles containing potentially dated statements from 2010 | All articles containing potentially dated statements

Recently, the State Administration of Work Safety issued a notice, will soon carry out safety technology “12 5″ plan of research. This marks the production technology of our national security, “12 5″ compilation of planning has officially entered the preparation stage. Dangerous chemicals industry is expected to prepare by planning and implementation of the “12 5″ period to further enhance the security technology to enhance industry and enterprise nature of safety.

    In recent years, China launched the “science and technology” strategy, continue to strengthen science and technology in the role of safety in production and vigorously promote advanced study and application of security technology, process, equipment and materials and technological achievements, to improve production safety situation is stable and has played a important role. Hazardous materials transportation safety monitoring and management systems, major hazards, monitoring and prevention technology, major hazard control and emergency rescue system demonstration project security and technological achievements and a large amount has been applied in greatly improved production safety and security ?? level effective containment of the hazardous chemicals of major accidents.

    SAWS had issued a special circular to strengthen the promotion of safety in production and technological achievements, requires all localities to coal mines, non-coal mines, hazardous chemicals, occupational hazards, emergency rescue and transport, fire and other sectors (areas) as the focus, by further improving assessment of scientific and technological achievements, identification, screening, release mechanism, to determine the safety of advanced technologies, processes, equipment and materials and technological achievements, to promote scientific and technological achievements regularly published directory. Also proposed as the source of enterprise security needs, the promotion of Chan Xueyan combination of encouragement and support to enterprises and institutions of higher learning, scientific research institutes build a security technology development platform to promote the direct transformation of scientific and technological achievements.

    Start planning research work aims to analyze the “12 5″ period of major scientific and technological needs of production safety, the selected key scientific and technological direction and priority themes. “12 5″ period, focusing on security technology innovation and safety to the theory of accident risk control in key technology to carry out research and important security technology research, demonstration and application of good science and technology, building safety technology standard system, to carry out emergency rescue techniques R & D and equipment. Among them, coal, non-coal mines, hazardous chemicals, emergency rescue, occupational hazards such as high-risk industries and areas of focus are the main targets.

    ”12 5″ period, hazardous chemical industry safety than continue to do advanced research and technology reserves, the increasing application of existing technology and equipment to promote advanced applications will also be an important task. HAN proof barrier technology, DCS control system, interlock emergency shutdown system and automation equipment, materials networking technology, Compass and GPS satellite navigation and positioning system technology, RFID (radio frequency electronic identification) technology, will be more widely used in crisis cosmetics production, storage and transportation management and monitoring. Among them, took my 5-year joint research technology with independent intellectual property rights and the international advanced level HAN proof barrier technology has been applied in some areas, effectively preventing the explosive explosion hazardous chemicals.

    Start the SAWS security technology “12 5″ planning research work on the hazardous chemicals industry to develop better targeted development plans security technology will play a great role. Hazardous chemical enterprises to take this opportunity to closely follow and actively cooperate with and accurately reflect the actual situation of enterprises, the preparation for the planning and implementation of plans and strategies.

According to Voice of “news and newspapers Summary” 6:40 reported in overseas M & A market to navigate the China National Chemical Corporation, and recently locked a target, quickly through overseas acquisitions to enter new chemical materials with high value-added areas. Ren Jianxin, general manager, said the company would explore the “international” driving corporate governance reform, promoting economic development mode.

    China Chemical Industry Group has set a foreign acquisition of Chinese enterprises in the highest frequency. The year 2006, China Chemical completion of the three consecutive large-scale overseas acquisitions: won the world’s second largest manufacturer of methionine French enhance human immunity, and Australia’s largest polyethylene producer Volcanoes, and with the cooperation of France, Rhodia, Bluestar has also caused the company became the world’s third largest manufacturer of organic silicon monomer.

    Ren Jianxin explains why the acquisition of China’s chemical preferences?? “We chose the acquisition of these developed countries are basically Europe and the United States, I want to buy them through the advanced enterprise in accordance with its practice, to change our corporate governance structure. I’ve been thinking join the WTO challenge for us is to what? I think that is how integration into the international community, how in accordance with international rules. you compete against the others, you do not know how to do, how competitive? ”

    ”Going out” of the Chinese chemical not forget to “get in.” This is the introduction of foreign strategic investment. October 2008, the U.S. Blackstone Group invested 600 million U.S. dollars acquisition of a wholly owned subsidiary of China’s chemical industry? A 20% stake in Blue Star, which is Blackstone’s first investment in China. Ren Jianxin, said the deal is worth. “We were the introduction of Blackstone as a strategic investor, did not fancy his money. Of course, was sold for 8.8 times is business, and certainly happy. To capital gains, only the transaction will add value, otherwise the only book prices nothing. ”

    M & A to manage a huge challenge. Continually extending the “internationalization” of the journey, the Chinese chemical industry’s corporate governance structure has quietly changed. “The next step of our international operations, we are prepared to do is to introduce the global chemical industry best practices. Is the global chemical industry to do the best, others how to do it, we follow suit. For example, the introduction of the world’s best managers, professional consulting firm, for example, our personnel, I do it outsourcing, and outsourcing to a professional consulting firm to do. ”

    China Chemical said the future they will be in material science, life sciences and three areas of environmental science to do something to gradually form a “3 +1″ pattern of the industry. With the international financial crisis, globalization and information technology industry, opportunities for transfer of management of change, speed up new industrial structure adjustment, made after the formation of differentiation and competitive advantage.

Before we can try to understand whether landscaping is more of an art or a science (or both), it would be well in order for us to give ourselves a brief introduction to it. Such an introduction would insure us from being guilty of running a discussion in which some cannot quite follow; on account of their not being conversant with the subject of the discussion. Landscaping, as it turns out, simply refers to the set of strategies that are employed in a bid to make the surroundings of the entities (which could be organizations, institutions and so on) look more presentable. When an organization decides to develop lush lawns on its head office’s grounds, that organization is said to be involved in a landscaping activity. Similarly, when an organization decides to plant some trees on its premises, it is said to be involved in landscaping. Often, landscaping involves planting things, though that is not all there is to it. Sometimes, where plants imply can’t grow, we may have things like careful arrangement of stone pebbles being undertaken to make the surroundings look more presentable. The bottom-line is that landscaping is all about making the landscape look more presentable; the landscape in this context being simply the ‘surroundings.’

So, is landscaping an art or a science?

Well, in order to establish whether landscaping is an art or a science, it will be important for us to have a working definition on what constitutes an art, and what constitutes a science. We won’t go into textbook definitions of the two. Rather, we will content ourselves with the vision of an art as any endeavor, or way of doing things that allows for creative input (and subsequent giving out of creative output).   Science, on the other hand, is all about precision: a system where given sets of inputs always yield given sets of outputs, and where there are precise ways of doing things. In chemistry, for instance, you know that when you mix chemical A with chemical B, you always get chemical C. There is no room for contention.

Now whether to view landscaping as an art or a science is quite a major challenge – but it ultimately depends on which landscaping approach we are looking at. Landscaping, as it is carried out nowadays has both artistic and scientific elements to it. There are, of course, some approaches to landscaping that have more science than artistry, just as there are some that are more about artistry than science. But there is hardly any approach to landscaping that can be said to be completely scientific (and bereft of artistry, seeing that landscaping is all about aesthetics). Similarly no approach to landscaping that can be said to be completely artistic and bereft of science.

Where landscaping involves the establishment of lawns, as is often the case, we see the science being employed in the growth of the vegetation that makes up the lawns. From the right land preparation techniques, to the selection of the right types of vegetation and their subsequent propagation, we see science going through and through. But if the resultant lawn is to be aesthetically appealing (which is really the point of developing it), a certain level of artistry is also necessary.

So in the final analysis, one is better off saying that landscaping is both an art and a science.

Introduction:  Polymer Morphology

Two different states or forms can be identified in which a polymer can display the mechanical or thermomechanical properties that can be associated with solids, viz., the form of a crystal or the form of a glass. It is not really the case that all polymers are able to crystallize. As a matter of fact, a high degree of molecular symmetry and microstructural regularity within the polymer chains are a prerequisite for crystallization to occur.  Even in those polymers, which do crystallize in any rate, the ultimate degree of crystallinity developed is mostly less than 100%.

Studies of physical form, arrangement and structure of the molecules or the molecular aggregates of a material system relates to what is known as its morphology.  Polymer morpho-logy covers the study of the arrangement of macromolecules over the crystalline, amorphous and the overlapping regions and the overall physical clustering of the molecular aggregates.

When cooled from, the molten states, different polymers exhibit different tendencies to crystallize at different rates depending on many factors including prevailing physical conditions, chemical nature of the repeat units and of the polymer as a whole, their molecular or segmental symmetry and structural regularity or irregularity, as referred to above.  Bulky pendent groups or chain branches of different lengths hinder molecular packing and hence crystallization.  The nature of the crystalline state of polymers is not simple and it should not be confused with the regular geometry of the crystals of low molecular weight compounds such as sodium chloride or benzoic acid.  There are polymers, which are by and large amorphous, and they have very poor tendency to get transformed into ordered or oriented structures on cooling to near or even below room temperature.  Natural or synthetic rubbers and glassy polymers such as polystyrene, acrylate and methacrylate polymers belong to this class.

In a crystalline polymer, a given polymer chain exists in or passes through several crystalline and amorphous zones.  The crystalline zones are made up of intermolecular and intramolecular alignment or orderly and hence closely packed arrangement of molecules or chain segments, and a lack of it results in the formation of amorphous zones.

Glass Transition and Melting Transition

On the basis of following the changes in a mechanical property parameter such as shear modulus with changes (rise) in the temperature of observation for polymer material systems, one can readily observe successively – (i) glass transition and  (ii) melting transition phenomena, more easily from a graphical plot , and may also have a measure of the glass transition temperature, Tg and the melting temperature,  Tm.

The glass transition and the melting transition may also be observed and ascertained from a plot of specific volume ( Vsp )  versus temperature.  Let us consider the various possibilities as a melt is cooled from the position A at a high temperature that corresponds to a relatively high Vsp value as well, fig. 1.  The path ABDG shows how the specific volume drops down as a low molecular weight compound is frozen.  As the melting temperature Tm is reached at the point B, a sharp discontinuity in Vsp is observed (BD).  The slopes AB and DG give measures of coefficients of thermal expansion of the liquid and the solid respectively.  The thermal expansion coefficient also suffers a discontinuity at Tm.

Fig.1:Schematic diagram highlighting possible changes in the specific volume (Vsp)

of a polymer with change in temperature .

We may however, start with a molten polymer material at A and observe volume change as described by the path ABHI and there is no discontinuity notable at Tm. The liquid line AB gets further extended beyond Tm with lowering of temperature and it is seen to suffer a change in slope at a much lower temperature, Tg and finally, turns into a different linear portion (HI) of a much lower constant slope.  Here, actually, the slope-change occurs over a small range of temperature (which may usually range about 5 – 100C), but extrapolation of the two linear parts allows right assessment of Tg by this method.  The zone HI represents the glassy state that ensues as the glass transition temperature is reached or just crossed as we go down in temperature.  Transition to the glassy state is also commonly termed as vitrification.  The region BH represents the existence of a super cooled liquid state or rubbery state of relatively poor dimensional stability, even under the influence of a low stress.

For all polymers, the glassy state is always attained finally on cooling, irrespective of whether the polymer being tested is crystallizable or not.  Even under situations favouring crystal formation, it does not necessarily mean that crystallization occurs rapidly or completely.  There still remains in most cases significant portions of amorphous zones after the primary crystallization process is completed.

The path ABCEFG in fig. 1 represents the case of a partly crystalline, partly amorphous polymer system.  On cooling down to Tm, crystallization begins and the characteristic discontinuity in Vsp becomes apparent even though the sharpness at which Tm is revealed is not as pronounced for polymers as for a low molecular weight compound, and this can be appreciated from the curvature of the portion of the path BCEF.  For such a system, FG represents the glassy zone and BA the melt or liquid zone and BCEF zone is by and large the amorphous rubbery (super cooled liquid) zone.  The point F, where slope between the segments EF and FG changes corresponds to the glass transition point, Tg, and the polymer in such a case remains by and large amorphous.  If partial crystallization would occur on cooling below Tm , the amorphous content decreases and in that case, the change in slope at Tg may be much smaller and harder to detect.

The path ABJK may appear as a variation of the path ABHI and here, AB describes the liquid state, BJ the super cooled liquid or the rubbery state and JK describes the glassy state.  The path ABHI shifts to ABJK under the condition of a higher cooling rate; it is likely that Tg is also displaced to a higher temperature (Tg?) for a faster cooling rate.

Thus, the temperature response of linear polymers may be viewed as divided into three distinctly separate segments:

1. Above Tm :

In this segment, the polymer remains as a melt or liquid whose viscosity would depend on molecular weight and on the temperature of observation.

2. Between Tm and Tg :

This domain may range between near 100% crystalline and near 100% amorphous chain molecular clusters depending on the polymer structural regularity and on experimental conditions.  The amorphous part behaves much like super cooled liquid in this segment.  The overall physical behaviour of the polymer in this intermediate segment is much like a rubber.

3. Below Tg :

The polymer material viewed as a glass is hard and rigid, showing a specified coefficient of thermal expansion.  The glass is closer to a crystalline solid than to a liquid in behavioural pattern in terms of mechanical property parameters.  In respect of molecular order, however, the glass more closely resembles the liquid.  There is little difference between linear and cross linked polymer below Tg .

The location of Tg depends on the rate of cooling.  The location of Tm is not subject to this variability, but the degree of crystallinity depends on the experimental conditions and on the nature of the polymer.  If the rate of cooling is higher than the rate of crystallization, there may not be an observable change at Tm, even for a crystallizable polymer.

The simple device used to follow volume changes upon cooling or heating is called a dilatometer, having a glass bulb or ampoule at the bottom fitted with a narrow bore capillary at the top, as in fig. 2.  A dilatometer may also be used in studying progress of polymerization with time at a given temperature by following volume contraction of liquid monomer system (the polymer being formed having a higher density than the monomer being polymerized).  For studies with a polymer say, polystyrene, the sample is placed in the bulb, which is then filled with an inert liquid, usually mercury and the volume changes with change of temperature (or sometimes at a constant temperature for a phase change, such as at Tm ) are then registered, as in a thermometer.  The expansion / contraction of mercury due to change of temperature is to be duly accounted for during experimentation for a volume change of the polymer sample.  The experiments are required to be accomplished by placing the dilatometer in a thermostated bath.  The sample must be immiscible with the displacement fluid and degreased to eliminate air entrapment.  Specific volume – temperature plot for polystyrene showing a distinct change in slope at 95.60C, indicates glass transition temperature, fig. 3.

Fig.2:A dilatometric arrangement for                 Fig. 3:Temperature dependence of

measurement of volume change of a                  specific volume for polystyrene indicating

the glass transition temperature, Tg.

(Courtesy: Tata McGraw –Hill, New Delhi)

Thus, it is a common experience that raising or lowering of temperature, just as application or withdrawal of stress, greatly influences the physical structure and properties of polymers.  With change of temperature a high polymer material passes through two distinct transitions characterized by (i) melting point or first order transition, denoted by Tm and (ii) the glass transition or second order transition, denoted by Tg .

Melting Point or First Order Transition

Melting of a crystalline solid or boiling of a liquid is associated with change of phase and involvement of latent heat.  Many high polymers possess enough molecular symmetry and/or structural regularity that they crystallize sufficiently to produce a solid-liquid phase transition, exhibiting a crystalline melting point.  The melting is quite sharp for some polymers such as the nylons, while in most other cases as for different rubbers and polystyrene, etc., the phase change takes place over a range of temperature.  Phase transitions of this kind, particularly in low molecular weight materials, being associated with sharp discontinuities in some primary physical properties, such as the density or volume, V,  [ V = (?G / ?P)T ] and entropy,  S,  [–S = (?G / ?T)P ] , which are first derivatives of free energy, are commonly termed first order transitions.  Although  we observe  melting,  a true first order  transition or  ideal  melting  in high polymers is frequently absent or missing, in view of the distribution of molecular weight and entanglements of chain molecules giving rise to the complex phenomenon of retarded flow or viscoelasticity.

Glass Transition or Second Order Transition

Glass transition or second order transition is not a phase transition and almost every polymeric or high polymeric material is characterized by a specific glass transition temperature (Tg) or second order transition point (SOTP), appearing well below its (crystalline) melting point, Tm.

At Tg, the thermodynamic property parameters S, V and H merely undergo change of slope when plotted against temperature, without, however, showing sharp discontinuities as observed in the case of first order transitions, such as the idealized plot shown in fig. 4.

Fig. 4: First order transition showing an idealized phase transition (melting or freezing): Trend of change of volume or entropy with rise of temperature, showing discontinuity at the transition point. (Courtesy: Tata McGraw –Hill, New Delhi)

The properties that suffer discontinuities at the glass transition temperature are:  heat capacity CP,  [ CP = (?H / ?T)P ], coefficient of thermal expansion ? ,

1                                 1          ?

?  =           (?V / ?T)P = . { (?G / ?P)T } P

V                                 V         ?T

and isothermal compressibility  K,

1                                    1

K  = – (?V / ?P)T = – (? 2G / ?P 2)T

V                                    V

which are second derivatives of free energy and it is for this reason that the glass transition temperature, Tg is commonly referred to as the second order transition temperature, fig. 5.  Refractive index (R1) also shows a sharp change at the glass transition point (Tg).

Fig.5: Trends of change in (a) specific volume, (b) coefficient of thermal expansion (?) or isothermal compressibility (K) and (c) refractive index (RI) of polymers with temperature indicating the glass transition  (Courtesy: Tata McGraw- Hill, New Delhi)

The glass transition is not a phase transition and therefore, it involves no latent heat.  Below this temperature normally rubber – like polymers lose flexibility and turn rigid, hard and dimensionally stable and they are then considered to be in a glassy state, while above this temperature, all normally rigid, stiff, hard glassy polymers turn soft and flexible, become subject to cold flow or creep and as such turn into a rubbery state.  The difference between the rubbery and glassy states lies not really in their geometrical structure, but in the state and degree of molecular motion.

Below the glass transition temperature, Tg, the chain segments or groups, as parts of the chain molecular backbone, can undergo limited degrees of vibration; they do not possess the energy required to rotate about bonds and change positions with respect to segments of the neighbouring chains.At or slightly above Tg, rotation sets in, particularly of side groups or branch units, and it is conceivable that only short range molecular segments rather than the entire high polymer molecule would rotate at this point.  The much higher coefficient of thermal expansion just beyond Tg is indicative of much greater degree of freedom of rotation.

At the respective glass transition or second order transition temperatures, different polymers may be viewed to be in an isoviscous state, and in reality, Tg is a common reference point for polymers of diverse nature, below which all of them behave as stiff rigid plastics (glassy polymer) and above which they appear leathery and rubbery in nature.  As we understand, a useful rubber is a polymer having its Tg well below room temperature, while a useful plastic is one whose Tg is well above the room temperature. Table 4.1 lists the Tm and Tg values of some common polymers.

Table 1:          Tm and Tg Values of Several Polymers

Polymer

Repeat Unit

Tm, 0C

Tg, 0C

Polyethylene

– CH2 – CH2 –

137

-115,-60

Polyoxymethylene

– CH2 – O –

181

-85,-50

Polypropylene (isotactic)

– CH2 – CH (CH3) –

176

- 20

Polyisobutylene

– CH2 – C (CH3)2 –

44

- 73

Polybutadine (1, 4 cis)

– CH2 – CH = CH – CH2 –

2

- 108

Polyisoprene (1, 4 cis), (NR)

– CH2 – C(CH3) = CH – CH2 –

14

- 73

Poly (dimethyl siloxane)

– OSi (CH3)2 –

- 85

- 123

Poly (vinyl acetate)

– CH2 – CH (OCOCH3) –

—

28

Poly (vinyl chloride)

– CH2 – CH Cl –

212

81

Polystyrene

– CH2 – CH (C6H5) –

240

95

Poly (methyl methacrylate)

– CH2 – C(CH3)( COOCH3) –

200

105

Poly tetrafluoroethylene

– CF2 – CF2 –

327

126

Poly caprolactam (Nylon 6)

– (CH2)5 CONH –

215

50

Poly(hexamethylene adipamide)

(Nylon 66)

–HN(CH2)6-NHCO–(CH2)4CO –

264

53

Poly (ethylene terephthalate)

– O(CH2)2 – OCO – (C6H4) CO –

254

69

Poly (ethylene adipate)

– O(CH2)2 – OCO – (CH2)4 CO –

50

-70

Molecular weight and molecular weight distribution, external tension or pressure, plasticizer incorporation, copolymerization, filler or fibre reinforcement, and cross linking are some of the more important factors that influence the glass transition temperature, melting point or heat – distortion temperature of a matrix polymer.  The comparative lowering of Tm and Tg for modification of polymer by external plasticization (plasticizer incorporation) and by internal plasticization (comonomer incorporation) is shown in fig. 6. Generally, a comonomer incorporation i.e. copolymerization is more effective than external plasticization in lowering the melting point, while the latter process (external plasticizer incorporation) is more effective than the former (copolymerization) in lowering the glass transition temperature.  Cross-linking causes significant uprise in Tg, as cross-links hinder rotation of chain elements, thus necessitating a higher temperature for inception of rotation of segments between cross-links.  Likewise, higher molecular weight, leading to complex, long range chain entanglements, restricts scope for segmental rotation and thereby causes a rise in the Tg value with a notable levelling off effect for molecular weight > 105.

Fig. 6: Schematic plots showing relative lowering of Tm and Tg of a polymer by separately incorporating (a) an external plasticizer.and (b) a comonomer by copolymerization.  (Courtesy: Tata McGraw –Hill, New Delhi)

Brittle Point

A polymer is also characterized by a temperature called the brittle point1 or brittle temperature (Tbr) which is close to or somewhat higher than its glass transition temperature (Tg ) for most high polymers.  As the temperature of the polymer in its rubbery state is lowered, the flexible nature and rubbery properties are gradually lost and the polymer stiffens and hardens; at an intermediate stage, a temperature called the brittle point is attained at or below which the polymer specimen turns brittle and breaks or fractures on sudden application of load.

For comparison of brittle points of different polymers, it is necessary to do the testing under specified conditions, including specified sample size and thickness, degree and rate of cooling, etc. as the test is empirical in nature.  The brittle point corresponds to a temperature at which the time interval of load application just matches or equals that needed by the test specimen to undergo the necessary deformation.  At a lower temperature, the specimen is unable to deform as rapidly, and hence it fails to withstand the load and thus breaks; above the brittle temperature, the time of load application is more than adequate for the specimen to absorb the applied energy and deform to escape fracturing or breakage.  Lower molecular weight limits the scope for long-range molecular interactions and chain entanglements and hence leads to a higher brittle temperature. Changes in Tg and Tbr with polymer molecular weight, as schematically illustrated in fig. 7, clearly shows that the trends of change for the two parameters are just the opposite.  The difference between the two is much narrower in the higher molecular weight range, but it gets progressively wider as the molecular weight decreases.

Fig. 7: Typical plots showing dependence of brittle temperature (Tbr) and glass transition temperature (Tg) on polymer molecular wieght.

(Courtesy: Tata McGraw –Hill, New Delhi)

Development of Crystallinity in Polymers

Polymer morphological studies primarily relate to molecular patterns and physical state of the crystalline regions of crystallizable polymers. Amorphous, semi-crystalline and prominently crystalline polymers are known.  It is difficult and may be practically impossible to attain 100% crystallinity in bulk polymers.  It is also difficult according to different microscopic evidences, to obtain solid amorphous polymers completely devoid of any molecular or segmental order, oriented structures or crystallinity.  A whole spectrum of structures, spanning near total disorder, different kinds and degrees of order and near total order, may describe the physical state of a given polymeric system, depending on test environment, nature of polymer and its synthesis route, microstructure and stereo – sequence of repeat units, and thermomechanical history of the test specimen.  Further, the collected data for degree of crystallinity may also vary depending on the test method employed.  The degree of crystallinity data shown in Table 2 must therefore be taken as approximate.

Polymers showing degrees of crystallinity > 50% are commonly recognized to be crystalline.  The cellulosics (cellulose acetate) and also regenerated cellulose (viscose) used as fibres have crystallinity degree lower than that of native cellulose, the base fibre.  The predominantly linear chain molecules of high-density polyethylene (HDPE) show a degree of crystallinity that is much higher than any other polymer known (even substantially higher than that for the low-density polyethylene (LDPE).  For HDPE, the attainable crystallinity degree is close to the upper limit (100%).  Atactic polymers in general (including those of methyl methacrylate and styrene bearing bulky side groups), having irregular configurations fail to meaningfully crystallize under any circumstances.

Table 2: Approximate Degree of Crystallinity (%) for Different Polymers.

Polymer

Crystallinity (%)

Polyethylene (LDPE)

60 – 80

Polyethylene (HDPE)

80 – 98

Polypropylene (Fibre)

55 – 60

Nylon  6 (Fibre)

55 – 60

Terylene (Polyester fibre)

55 – 60

Cellulose (Cotton fibre)

65 – 70

Regenerated cellulose (Viscose rayon fibre)

35 – 40

Gutta  Percha

50 – 60

Natural rubber (Crystallized)

20 – 30

Figure 8 provides a comprehensive idea about crystallization rate (volume change with time) at different selected temperatures.  For high density polyethylene (HDPE), as the temperature is lowered, the volume changes proportional to the rates of crystallization rapidly increase and well below the actual melting point (1270C), the volume change soon becomes so rapid that measurements and observation become uncertain and difficult, if not practically impossible.  The obvious consequence of the very high rate of crystallization in polyethylene is that it is virtually impossible to obtain and isolate the polymer in the amorphous state at room temperature i.e., under ambient conditions.  Sudden chilling or quenching of the melt to below room temperature results in a material which is still largely crystalline, though expectedly with the likelihood of a somewhat lower degree of crystallinity than otherwise developed on normal melt – cooling.  The reason for this state of affairs is that the time required for crystallization is far shorter than the time taken for cooling the test polymer specimen.

Fig. 8: Plot of relative volume with time (min) showing densification of polylethylene on development of crystallinity at different specified temperatures.

(Courtesy: Tata McGraw –Hill, New Delhi)

For practical reasons, therefore, the process of polymer crystallization is very conveniently studied and measured with confidence using a polymer that is by and large amorphous; natural rubber is one such polymer.  The merit of using rubber as a model material for study of polymer crystallization is that the crystallization process is slow to allow due measurements with easy manipulations and it takes place in a convenient range of temperature.

It is worthy of mention that all rubbers (particularly those which are copolymers) are not crystallizable.  Only those built up of chains characterized by chemically identical and regular repeat units, such as natural rubber, 1, 4 cispolyisoprene and certain grades of polychloroprene are capable of crystallization.

Crystallilzation of Rubber on Cooling

If unvulcanized natural rubber (NR) is held at a fixed low temperature, say 00C, it slowly gets somewhat stiffened and hard, and loses flexibility and softness proportionately.  However, the material still retains some degree of flexibility and toughness.  The observed physical change is also associated with some enhancement in density or lowering in volume; the associated changes are consequences of slow development of crystallinity in the material.

Crystallization in an ordinary low molecular weight liquid on cooling to or below the freezing point takes place very rapidly, consequent to ready and fast molecular rearrangement from a disordered state to a very regular state of packing.  A polymer melt system is, however, much more complicated due to chain entanglements, restricting free mobility of the chain segments, and consequently, hindering and delaying the desired rearrangement process on cooling.  For rubber – like polymers, the time scale of crystallization is commonly much longer than for liquids of low molecular weight materials.

Fig. 9: Densification on crystallization of natural rubber,

plot of relative volume vs. time (hour) at different temperatures.

(Courtesy: Tata McGraw –Hill, New Delhi)

Trends of change in relative volume of natural rubber (NR) with time due to crystallization at different low temperature are shown in fig. 9.  The attainable maximum crystallinity and the time span required for this to happen are very much dependent on the temperature of observation6.  In each case, the volume contraction rate is relatively slow initially; the volume contraction (or crystallization) rate shows an increasing trend with time, passes through a higher steady zone at an intermediate time period and then finally drops down, decays or levels off giving a maximum attainable development of crystallinity degree at a given temperature.  Lowering of temperature causes enhancement in the steady rate of crystallization of NR till about –250C, where the steady rate vs. temperature plot, fig. 10 passes through a maximum.  Further reduction in the temperature of crystallization causes a falling trend in the steady rates of crystallization as in fig.10.   The crystallization is (nearly) completed in about five hours at –250C.  In natural rubber, the degree / extent of crystallinity under the most favourable situation does not exceed 30%.

Fig. 10: Plot indicating trend of change in steady rate of crystallization with change in temperature for natural rubber (Courtesy: Tata McGraw –Hill, New Delhi)

Mechanism of Crystallization

As the polymer melt is kept at a temperature close to or slightly above its melting range, the initial slowness in crystallization rate build up (delayed crystallization) is linked with the initial process of nucleation.  Growth of crystallites is contingent upon the development and existence of a certain number of very tiny growth centers or nuclei for the deposition of oriented chain segments.  The growth centers are initially formed on extended cooling or holding of the melt at the specified temperature by coming together of a small number of chain segments in the course of their random motion (micro Brownian motion) under the prevalent situation.  Nucleation is, however, common to all processes that turn an initially homogeneous medium into a heterogeneous system as a consequence of deposition of a separate phase.

As the growth is sustained and continued, the opposing effect of chain entanglements becomes increasingly severe and ultimately critical, thus imparting severe restrictions on the mobility of chain segments and thus making it difficult for them to get to a position for attachment to any one of the crystallites formed.  Beyond this stage, the crystallization rate diminishes sharply and finally, the process dies down.

Lower temperature favours nucleation and lower thermal energy of the chain segments makes it less likely that a nucleus once formed would disappear again, the net result being a gain in the number of nuclei and an increase in the overall rate of crystallization with progressive lowering of temperature. At progressively lower temperatures, however, the overall energy of the polymer system including that available to chain segments tend to get so much lowered that the segments seem to practically lose much of their mobility and hence their deposition on a nucleus formed is progressively hindered much more effectively and there appears a sharp dropping trend in the rates of crystallization.  For natural rubber, the crystallization process gets effectively frozen out below – 500C, fig. 10.

Stress – Induced Crystallization of Rubber

It is a common knowledge and a matter of wide experience that stretching of a strip of vulcanized rubber makes it develop a temporary crystallinity by axial orientation of the chain molecules along the direction of stretching and that the orientational effect disappears instantly on withdrawal of the stretching force.  A strip of raw or unvulcanized rubber also develops crystallinity when subjected to high extensions on application of a stretching force, but it remains more or less in the extended state (in view of the absence of restraining cross links) without notable retraction to its original state on stress release.  However, when heated carefully in the subsequent stage, such as by dipping the test strip into slightly warm water (temperature > 300C) the crystals melt and allow the strip to revert largely to its unstrained state.

The cross links in the vulcanized rubber act as points of reinforcement and are responsible for accumulation of the strong retracting or restoring force that comes into play in breaking the stress – induced orientation (or the crystalline structure) on withdrawal of the applied stress.  In the unvulcanized system, the absence of cross links allows varied degrees of chain uncoiling if not chain slippage on low/moderate extensions and whatever elastic restoring force accumulates is far too insufficient or inadequate to break the crystalline structure and induce dimensional recovery.  Raising the test strip temperature to 300C or slightly above this level, allows melting of the axially oriented crystallites, causing the rubber chain molecules to coil up and the test strip to retract to its initial or near initial (random / unoriented) state.

Fig. 11: Time-dependency of stress-induced crystallization (densification) of unvulcanized rubber held at 00C for different indicated orders of fixed extensions, plot of density change (%) vs. time (min). (Courtesy: Tata McGraw –Hill, New Delhi)

Fig.11shows the time-dependency of crystallization of unvalcanized rubber at a low temperature (here 00C) on application of different fixed extensions revealing trends of % change (increase) of density with time of specified stretch application. Moderate extensions produce effects as observed for lowering of temperature.  For extensions > 100%, however, the crystallization rates are very high, such that only final stages are practically observable.

Melting of Rubber

Beyond this point, further enhancement in temperature gives a linear plot much in tune with the thermal volume expansion of the amorphous rubber. Fig.12:‘Melting curve’ showing increase in              Fig. 13: Melting curve showing a plot

specific volume (cm3/g) vs. temperature (0C)          of relative volume vs. temperature for rise for natural rubber                                                             polyethylene.

(Courtesy: Tata McGraw –Hill, New Delhi)

The melting curve of the highly crystalline polymer polyethylene characteristically shows a sharp volume change and the temperature of the beginning and end of the melting process is usually limited well within a range of 100C or to be more precise, within a span of 50C.  If after melting the rubber, the temperature is lowered again, fig. 12, the linear volume contraction for the amorphous rubber continues to much lower temperatures and the melting curve is not retraced in the reverse direction simply because, measurable recrystallization fails to occur in the time – span of the experiment.  For the highly crystallizable polymer, polyethylene, however, the melting and crystallization / recrystallization processes are by and large reversible in a practical sense and the recrystallization curve is mostly a retrace of the melting curve, fig. 13 from the opposite direction.

For the amorphous polymer, natural rubber, whereas melting occurs over an extended range of temperature, the beginning of melting and the temperature range over which the melting process is accomplished and completed are also largely dependent on the temperature at which the preceding crystallization was done.  Usually, melting begins at a temperature that is 4–60C higher than the temperature at which the preceding crystallization was accomplished, fig. 14.

Fig. 14: Plot indicating dependence of melting range of natural rubber on temperature of crystallization, the diagonal line below the melting range (shaded zone) indicating temperature of crystallization. (Courtesy: Tata McGraw –Hill, New Delhi)

Thus, it is possible to have simultaneous or consecutive melting and recrystallization in a given piece of rubber as it is slowly heated over the melting range (shaded area in fig. 14) after initial crystallization and then held at a specific temperature within that (melting) temperature range.

Polymer Single Crystals

Single crystals of different readily crystallizable polymers can be grown by slow cooling and precipitation from very dilute solutions.  They appear in the form of very thin plates or lamellae, usually diamond shaped with spiral growth pattern and showing step – like formation on the surface.

The single crystals are very small in size and can not be examined by x-ray diffraction.  However, they can be readily and conveniently studied by electron microscopy.  Electron diffraction pattern and electron micrographs reveal certain interesting features about polymer single crystals.  The thickness of the lamellae is very small (100 – 200 Å) compared to the usual polymer chain length.  The diffraction pattern reveals with no uncertainty that the chain axis is directed perpendicular to the plane of the lamellae.  The structural pattern of the single crystal is thus understood well on the basis of the well known folded chain theory.  This theory envisages that a single molecule of the polymer must bend or fold forwards and backwards many numbers of times across the thickness of the lamellae.  Such folded chains are readily stacked in the crystal lattice with ease.  It is widely believed that the single crystal comprises an array of folded chains packed individually and successively between the top and bottom surfaces or planes and on the growing edges of the lamellae as schematically shown in fig. 15.

Fig. 15: Chain folding to yield polymer single crystal (schematic)

This kind of oriented structure or crystal formation involving whole individual polymer molecules discretely without interference or interposition of other molecules is apparently made possible due to large distances that exist to ideally separate the individual molecules in very dilute solutions, fig. 16.  The wide – distance separation ensures practical elimination of chain entanglements.  Hence, when one segment of a polymer molecule gets attached to one of the thin edges of the growing crystal, it faces practically no competition from other far away molecules for occupation of the close by, adjacent lattice site.  There will be little hindrance to the successive occupation of immediately adjacent sites by segments of the same molecule by a chain folding mechanism that would continue till the whole molecule is drawn and arranged and oriented into the folds.

Fig. 16: Separation between polymer chain molecules in (a) very dilute solution and (b) concentrated solution (schematic). (Courtesy: Tata McGraw –Hill, New Delhi)

Structure of Bulk Polymers

Crystalline polymers obtained on cooling of their melts likewise produce electron micrographs showing the lamellae structure for the crystallites and providing little direct evidence for the presence of major amorphous regions.  An idealized model of the lamellae structure as in fig. 17(a) is probably far from the real state of affairs and it may not be applicable to all types of polymers.  Most polymers other than the polyethylenes (HDPE and LDPE) contain amorphous regions to the extent of 20 – 50% or even more, distributed in the material along with the crystalline domains.  In the structural model for a real system, a provision has to be made to accommodate the amorphous material.  In a fringed – micelle or fringed – crystallite model, fig. 17 (b), the disoriented, amorphous material fractions are shown interspaced between the randomly distributed and positioned crystallites.  This model explains and reveals the morphological features in such materials as rubbers and some cellulosic or other non-crystalline or semi-crystalline polymers with isotropic property pattern.  For different polymers of intermediate orders of crystallinity, random mix of fringed micelle model and regularly stacked lamellae model may represent the overall structural pattern. These structural concepts make allowances for imperfections commonly encountered, such as the interlamellar entanglements, molecular loops of diverse dimensions, irregular fold lengths and interconnecting chains passing through different lamellae.

Fig. 17: Schematic representation of (a) ideal stacking of lamellar crystals (discrete folded chains), (b) fringed – micelle model showing randomly distributed amorphous and crystalline zones, and (c) interlamellar amorphous model. (Courtesy: Tata McGraw –Hill, New Delhi)

A model consisting of stacks of lamellae interspaced with and connected by amorphous regions may be referred to as the interlamellar amorphous model, fig. 17(c).  This unique model provides the most useful approach to the understanding of the mechanical property profile of bulk crystallized polymers of moderate to high degrees of crystallinity.  The different degrees of ductility and cohesive character are direct consequences of the existence of interlamellar ties.  Somewhat like stacks of bricks without clay or sand – cement interlayers as the mortar, stacks of lamellae (crystals) without the existence of interlamellar tie molecules such as those obtained by slow cooling of a very dilute solution, would prove relatively fragile and brittle.  The tie molecules reduce brittleness and infuse ductility and stability.

Spherulites

The most distinctive, prominent and common feature of bulk crystallized (melt cooled) polymers is the development of spherulites, i.e. spherical crystallites. A spherulite is characteri-zed by a symmetrical structure build – up arising as a consequence of the cooperative growth of oriented chain segments called crystallites radially outward from a core or nucleus in three dimensions, fig. 18.  Bulk crystallized polymers are, in fact, not merely a series of stacked lamellae separated and interconnected by amorphous regions; the lamellae units are intricately organized in a radial fashion within the spherulites.  The crystallization process through which the spherulites are formed follows sequential steps beginning with nucleation.  The nucleation process may be aided by intentional addition of a foreign substance, called the nucleating agent.  The nucleating agents by their presence reduce the size of the spherulites by increasing the number of nuclei.  Growth of large spherulites contributes to enhanced brittleness.

Fig. 18: State of spherulite growth for polypropylene [(a) and (b)] and (c) schematic structure of a spherulite (radial growth and branching of the lamellae with an enlarged portion showing chain folding perpendicular to the spherulitic radius). (Courtesy: Tata McGraw –Hill, New Delhi)

It is generally observable that most polymers continue to slowly densify long after spherulite growth is complete.  The post – primary crystallization densification occurs both in the interspherulitic regions and intraspherulitic regions.  The densification due to secondary crystallization slowly taking place after the primary process of spherulite growth leads to thickening of the lamellae, as chain segments are gradually pulled in from the amorphous zones.  One more consequence of the secondary crystallization is the trend toward increase in brittleness.  The whole after-effects on mechanical and related properties of the polymer are recognized to be complex and they depend largely on many factors including the rate and span of cooling, annealing, cold – drawing or stretch – cooling.

Thermal Analysis

The thermal properties of polymers are conveniently studied by employing such techniques as differential thermal analysis (DTA) and differential scanning calorimetry (DSC).  The DTA technique usually allows detection of thermal response and effects that

Fig.19: A block diagram for a DTA apparatus    Fig. 20: A typical DTA thermogram indicating

thermal changes of a crystallizable polymer (schematic)

(Courtesy: Tata McGraw –Hill, New Delhi)

accompany chemical or physical changes in a material system when it is heated or cooled in a programmed manner through a zone of transition, phase change, chemical transformation or decomposition. It allows location and measurement of glass transition temperature, Tg, the crystallization temperature (Tc), the (crystalline) melting point (Tm), and the temperatures of thermal / oxidative degradation, cross linking and other types of reactions.  Figures 19 and 20 show respectively a block diagram of a DTA equipment and schematic representation of a DTA thermogram.

In practice, the material sample and a thermally inert reference material placed in the respective holders of the DTA cell are heated in a programmed manner.  Any physical or chemical change in the test material at a specific temperature, which is the characteristic feature of the material under study, is usually associated with thermal change leading to a notable difference in temperature (?T), between the test and reference materials held in the furnace temperature.  ?T is recorded as a function of temperature, T.  For no thermal change / transition, in the test sample, ?T remains nearly unchanged (constant).  In DTA, the correlation between ?T and energy changes over a specific transition or transformation (reaction) is uncertain and unknown, thereby making the conversion of the endotherm or exotherm peak areas to energies also uncertain.  However, the DTA technique is applicable to virtually all polymers and many other material systems, revealing in most cases qualitative information about the thermal effects giving clear indications of the transition (endothermic or exothermic) temperatures, fig. 20.  The technique is commonly unsuitable for quantitative measurements of parameters such as heat capacity, heat of fusion or heat of crystallization (for crystallizable polymers) or change in specific heat associated with glass transition for amorphous polymers; quantitative measurements are, however, readily done employing differential scanning calorimetry (DSC).  In DSC, the test sample and the reference material are heated separately by individually controlled units.  The power or electrical energy inputs to those heaters are controlled and continuously adjusted consequent to any thermal effect in the test sample in such a manner as to maintain the two at identical temperatures.  The differential power or heat energy needed to achieve this state of affairs is recorded against the programmed temperature of the system. For transition involving latent heat such as for fusion, the heat of the transition (fusion) is determined by integrating the (heat) energy input over the time interval covering the transition in question.

Different polymers decompose over different ranges of temperature releasing some volatiles and leaving some residues.  Thermogravimetric analysis (TGA) is a useful analytical technique for recording weight loss or weight retained of a test sample as a function of temperature, which may then be used for an understanding of the chemical nature of the polymer.  Along with the analysis of the released volatiles and the residue left behind, TGA provides information about thermal stability, and decomposition of the material in an inert atmosphere or in air or oxygen and about moisture content and other volatiles or plasticizer content, ash content and extent of cure for cross linked polymer.  The test sample is placed in a furnace while it remains suspended from one arm of a precision balance.  The TGA thermograms are obtained by recording change in the weight of the test sample as it is held at a fixed temperature or as it is dynamically heated in a programmed manner.  TGA thermograms of some selected polymers are shown in fig.21.

Fig. 21:TGA thermograms of some selected polymers

(Courtesy: Tata McGraw –Hill, New Delhi)

References

Ghosh, P., Polymer Science and Technology – Plastics, Rubbers, Blends and Composites, 2nd ed., Tata McGraw Hill, New Delhi, 2002. Hiemenz, P.C., Polymer Chemistry – The Basic Concepts, Mercel Dekker, New York, 1984. Billmeyer, Jr., F.W., Text Book of Polymer Science, 3rd ed., Wiley – Interscience, New York, 1984. Schmidt, A.X., and C.A. Marlies, Principles of High Polymer – Theory and Practice, McGraw-Hill, New York, 1948. Mandelkern, L., Crystalization of Polymers, McGraw-Hill, New York, 1964. Wood, L.A., Advances in Colloid Science, H. Mark and G.S. Whitby Eds., Wiley Interscience, New York 1946, Vol. 2, pp. 57 – 95. Bekkedahl, N. and L.A. Wood, Ind. Eng. Chem. 23 (1941) 381. Geil, P.H., Polymer Single Crystals, Interscience, New York, 1963.

Selected Readings

1. Maiti, S., Analysis and Characterization of Polymers, Anusandhan Pub., Midnapore,

2003.

2. Turi, E.A. Ed., Thermal Characterization of Polymeric Materials, Academic Press,

New York, 1981.

3. Fried, J.R., Polymer Science and Technology, Prentice – Hall, Englewood Cliffs, 1995.

4. Treloar, L.G.R., Introduction to Polymer Science, Wykeham Pub., London, 1970.

Careers in industrial science continue to expand with positions opening up in both government and private institutions, especially in the area of research and manufacturing. Graduates can choose from a range of careers in agricultural and biological sciences, the information and technology sector, food and pharmaceutical companies, as well as mining and mineral exploration.

With the unparalleled expansion of scientific knowledge, industrial scientists have the opportunity of working at the leading edge of scientific developments no matter whether they have a leaning towards biology, chemistry or physics.

There will be a career path in industrial science in a variety of fields and this article will look at five fascinating careers to consider.

Industrial Microbiology. If you have a penchant to work in a multidisciplinary scientific environment, then industrial microbiology or biotechnology could interest you. Processes and production problems often take scientists in a variety of directions which means that an industrial microbiologist has to be adaptable across such fields as bioengineering, biochemistry and molecular biology. Career pathways can lead you into fields such as antibiotics and vaccines as well as many other healthcare products and even food and beverages which are produced by microbial activity, for instance, cheeses, yoghurts.

 

Environmental Engineering. Environmental engineering suits graduates who are concerned about the man-made environment and issues relating to water quality, waste disposal, air quality and dealing with contaminated land. Today, research into the prevention of pollution is supported by government and private agencies alike and graduates can expect to work with mechanisms of sustainability in either private companies or government research facilities.

 

Chemical Engineering. Chemical engineering provides a practical link between the theory of science and manufacturing. Industrial scientists with a preference for working in this area will be involved in designing of equipment and development of large chemical manufacturing processes in a variety of industries including photography and photographic equipment, manufacturing chemicals and health care products

 

Academic Research. Most academic careers in the area of industrial science will attract high achieving practitioners looking to develop their research and, naturally, to teach within universities. Professorial appointments are highly regarded and provide satisfying careers for experienced scientists. Although opportunities are limited, with the expansion in industrial scientific jobs as a whole, academic posts are becoming more frequently advertised.

 

Nanotechnology. Within the emerging realm of nanotechnology, jobs are being created across a diverse range of activities. From creating cosmetics and researching the nature of matter, to medical diagnostics and developing better batteries are just a few opportunities that provide blossoming careers for industrial scientists. It is safe to say there is a revolution in manufacturing and in production of new materials. The new ways in which these are made is largely under the direction of a highly qualified industrial scientist. You could find yourself working for a sports equipment company or the army. The choices are almost endless.

The outlook for employment in the area of industrial science is rapidly increasing. Government predictions of job growth show that this growth will continue for at least the next three years unabated. Even in times of slower employment growth, it is apparent that many companies will continue to research and develop new products requiring industrial science expertise.

Regardless of the field of chosen, most people working in Industrial science will gain first hand experience with cutting edge analytical measurement techniques. Measurement technologies such asLaser Diffraction, Dynamic Light Scattering, Spectroscopy, HPLC and Rheology are widely used in Industrial science jobs. With the help of these cutting edge technologies people around the worlds are expanding development of exciting new products that will shape our future world.

 

Polymers and plastics, especially polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polystyrene and polycarbonate comprise about 80% of the industry’s output worldwide.[citation needed] Chemicals are used to make a wide variety of consumer goods, as well as thousands inputs to agriculture,

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manufacturing, construction, and service industries. The chemical industry itself consumes 26 percent of its own output.[citation needed] Major industrial customers include rubber and plastic products, textiles, apparel, petroleum refining, pulp and paper, and primary metals. Chemicals is nearly a $3 trillion global enterprise, and the EU and U.S. chemical companies are the world’s largest producers.[citation needed]

[edit] Product Category Breakdown 1928 ?Future war and german chemical industry?

Sales of the chemical business can be divided into a few broad categories, including basic chemicals (about 35 to 37 percent of the dollar output), life sciences (30 percent), specialty chemicals (20 to 25 percent) and consumer products (about 10 percent).[citation needed]

Basic chemicals, or “commodity chemicals” are a broad chemical category including polymers, bulk petrochemicals and intermediates, other derivatives and basic industrials, inorganic chemicals, and fertilizers. Typical growth rates for basic chemicals are about 0.5 to 0.7 times GDP

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. Product prices are generally less than fifty cents per pound. Polymers, the largest revenue segment at about 33 percent of the basic chemicals dollar value, includes all categories of plastics and man-made fibers. The major markets for plastics are packaging, followed by home construction, containers, appliances, pipe, transportation, toys, and games.

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The largest-volume polymer product, polyethylene (PE), is used mainly in packaging films and other markets such as milk bottles, containers, and pipe. Polyvinyl chloride (PVC), another large-volume product, is principally used to make pipe for construction markets as well as siding and, to a much smaller extent, transportation and packaging materials. Polypropylene (PP), similar in volume to PVC, is used in markets ranging from packaging, appliances, and containers to clothing and carpeting. Polystyrene (PS), another large-volume plastic, is used principally for appliances and packaging as well as toys and recreation. The leading man-made fibers include polyester, nylon, polypropylene, and acrylics, with applications including apparel, home furnishings, and other industrial and consumer use. The principal raw materials for polymers are bulk petrochemicals.

Chemicals in the bulk petrochemicals and intermediates are primarily made from liquefied petroleum gas (LPG), natural gas, and crude oil. Their sales volume is close to 30 percent of overall basic chemicals. Typical large-volume products include ethylene, propylene, benzene, toluene, xylenes, methanol, vinyl chloride monomer (VCM), styrene, butadiene, and ethylene oxide. These chemicals are the starting points for most polymers and other organic chemicals as well as much of the specialty chemicals category.

Other derivatives and basic industrials include synthetic rubber, surfactants, dyes and pigments, turpentine, resins, carbon black, explosives, and rubber products and contribute about 20 percent of the basic chemicals’ external sales. Inorganic chemicals (about 12 percent of the revenue output) make up the oldest of the chemical categories. Products include salt, chlorine, caustic soda, soda ash, acids (such as nitric, phosphoric, and sulfuric), titanium dioxide, and hydrogen peroxide. Fertilizers are the smallest category (about 6 percent) and include phosphates, ammonia, and potash chemicals.

Life sciences (about 30 percent of the dollar output of the chemistry business) include differentiated chemical and biological substances, pharmaceuticals, diagnostics, animal health products, vitamins, and crop protection chemicals. While much smaller in volume than other chemical sectors, their products tend to have very high prices—over ten dollars per pound—growth rates of 1.5 to 6 times GDP, and research and development spending at 15 to 25 percent of sales. Life science products are usually produced with very high specifications and are closely scrutinized by government agencies such as the Food and Drug Administration. Crop protection chemicals, about 10 percent of this category, include herbicides, insecticides, and fungicides.

Specialty chemicals are a category of relatively high valued, rapidly growing chemicals with diverse end product markets. Typical growth rates are one to three times GDP with prices over a dollar per pound. They are generally characterized by their innovative aspects. Products are sold for what they can do rather than for what chemicals they contain. Products include electronic chemicals, industrial gases, adhesives and sealants as well as coatings, industrial and institutional cleaning chemicals, and catalysts. Coatings make up about 15 percent of specialty chemicals sales, with other products ranging from 10 to 13 percent.

Specialty Chemicals are sometimes referred to as “fine chemicals”

Especially in science it is utmost to survive if someone is competent to sale the ideas. Then the remittances are recorded in the history, all worlds famous Greek, Sumerian, Egyptian civilizations were contribution to millions of dedicated workers who sacrificed themselves for creating history. An element of salability is frontier science now in contrast to 17th to 19th centuries where time was for developing or fostering fundamentals ideas or concepts. However the 20th century has been a transition or interface of the idea developmental sciences and idea marketing or commercialization. Currently, it has become an urgency of the time to cater the basic needs of an increasing pressure of the population growth globally. Now commercialization of science has become inevitable and is gaining grounds further in all frontal areas like communication, transport, electronic gadgets, auto transports, information technology, education, electronic and print media, medical and medicinal sciences, house and building technology, warfare and so on and so forth. It is different issue that few are misusing scientific information and technology for unethical actions. Though such section of society dare to commercialize scientific ideas but in negative direction. Of course time is there to dare and dreams to socialize sciences.

Hence the scientific dreams open new frontiers of sparkling world to facilitate people’s working, especially, for experimentation, chemical combinations and formulations to unveil their hidden industrial potential, novel ideas and valuable applications thereof. For such appreciable working advancements and industrial applications, certain workable, approachable, accessible, fascinating and interest burning vehicles are required. The vehicles must not be routine science but must also safeguard environmental and user’s safeties with novel concepts to resolve unnoticed, unbreakable and undreamable hypothesis and science involved in them.

The science is a boat or bundles or ideas generating fertile land to carry forward an implementation and transformation into reality which is based on dreams. Kekule, a German organic chemist in 1865, dreamt benzene structure, Pythagoras, a Greek mathematician Pythagoras, dreamt height of fallen tree, Newton, dreamt of falling apple from tree why to come downward only why not to sky, Einstein, dreamt E=mc2 mass energy relationship, though its immediate application in year 1945 by bombarding nuclear bombs on Nagasaki and Hiroshima, massacred thousands and thousands of Japanese. They developed their dreams into respected theories and are being practiced by society as success science stories.

Similarly, the Survismeter was dreamt and its science, concept, idea, were industrially transformed in service of man. The dreamer of the Pythagoras theorem, benzene structure, mass energy relationship, gravitation law (Newton) are no more but dreamer of the survismeter is moving forwards in search of new science. Of course, there are certain difficulties associated with the surviving dreamers or inventors of success science stories as people sometimes have different blank slates for them. For example, many inventors including Galileo, an Italian Scientist, faced tough challenged to put forwards his scientific discoveries.     

It is highly appreciable that many researchers like Nepal Chemical Society, have shown gesture initiative to launch the survismeter in Nepal. Notably sincere and honest researchers Professor Sujeet Kumar Chatterjee and Ajaya Battarai, Tribhuvan University, have moved forwards a vision of survismeter to those who are seriously pursuing science for learning as students or practicing professionals as teachers, researchers and application scientists to create new milestone in Asian countries. Similar other visionaries are awaited to come forward for fostering this Asian invention. Their notice and attention probably may ignite interest further for novel research out of Survismeter Success Science Story-S4. The survismeter is an Asian initiative and a matter pride of Asian countries, with provisions and opportunities to measure Surface Tension, Interfacial Tension, Excess Surface Concentration, Wetting Coefficients, Viscosity and Friccohesity together. Its use encourages savings of 98% experimental resources like experimenter’s time, laboratory infrastructure and occupation, electricity, manpower, water and chemicals, with no experimental hazards and no discharge of polluting effluents along nurturing, ridging, scratching, tinkling, sprinkling and trudging  notions for science among budding and would be scientists.

Its science is R4-Reduce-Reuse-Recycle-Redsign and nothing goes waste. The survismeter works on theory of Potential Energy and Liquid Distribution and Equilibrium [PELDE] in CPU-controlled pressure unit. Now the S4 is a glaring example before all of us to socialize the science as a green and clean technology [GCT] whose adoption right from beginning could prevent environmental hazards and also accelerate natural ecosystem, especially in Nepal, a country of green lands. Tribhuvan University, Department of Chemistry, Mahendra Morang Adarsh Multiple Campus, deserves Heroic Public Reception for kindling the survismeter by leaps and bounds from its heartland.The origin of ideas, difficulties faced in, calibration at National Physical Laboratory, New Delhi, and Patent by Singapore Govt., successful commercialization, all, have been a unique kind of intensified struggle. Now it has been installed worldwide along developing new applications in a form of substantial assets in hands of researchers within economic boundaries.All these events took one and half decades in notching and framing a new Chapter added to Science and Technology from Asian lands. The fundamental science of the survismeter is credited with a well known notion “Need is mother of invention” but latter on it was noted and tilted “Zeal is mother of invention” due to its elongated struggle and highly discouraging public criticism without analyzing its merit. Since people are conventional but talk nonconventional, this creates fission to their vision. The conventional people are within box thinking and doing in very routine way and dare not for new look. However they pose as their thinking and doing both, are novel. New ideas at all cost must be appreciated and encouraged for validity and industrial validity. Otherwise as none saw falling apple in Brookfield’s, Cannon, Ubbelohde viscometers for viscosity and Wilhelmy Plate Tensiometer for surface tension, individually are being imported from Western and European countries mainly from USA. The detailed information about survismeter science, its applications etc could be sought from references listed under.