 | Bill Moyers: Toxic Chemicals PVC monomer pt. 1 This is an excerpt from Moyer's investigation into the massive cover-up amongst the major chemical manufacturers like Dow, B. F. Goodrich, and the many others that aired years ago. |
 | Bill Moyers: Toxic Chemicals PVC monomer pt. 2 This is the 2nd excerpt from Moyer's investigation into the massive cover-up amongst the major chemical manufacturers like Dow, Union Carbide, DuPont, Esso, B. F. Goodrich, and the many others that aired years ago, and which deals with chemicals like PVC, among others. |
 | Come Together In laboratory 4 we studied how enzyme activity is affected by environmental conditions. Enzymes permit cells to carry out the many functions that are required in a living system. Every enzyme has a specific substrate and a specific function. They change their substrate in one of two ways: either by dehydration synthesis (a monomer is added to another molecule) or hydrolysis (a monomer is removed from another molecule). Each enzyme has a unique conformation that enables them to perform their specialized tasks. The substrate molecule meets the enzyme at the active site, where the reaction takes place and the substrate is altered. The conformation of a particular enzyme depends on several levels of protein structure. First is sequence of amino acids or the primary structure. The attraction between these molecules is usually expressed as hydrogen bonds. The secondary structure is characterized by a unique sequence on hydrogen bonds between more distant molecules on the chain. In this lab we saw changes in the effectiveness of the enzymes when the secondary structure of the enzymes is altered. Tertiary and Quaternary structures describe successively larger parts of a protein, influenced by other electrostatic bonds. Enzymes possess an affinity for their substrate. We observed the enzyme catechol oxidase and how it is affected by temperature. Test tubes of catechol oxidase of various temperatures were inserted into a spectrometer to determine the amount of enzyme activity. The spectrometer measures the amount of product from the reaction over a period of time and determines the concentration of the solution by measuring the amount of light that is absorbed by the solution. We noticed that the enzymes at room temperature were the most active over time. The enzymes that were heated and cooled were denatured and over time became less and less active. |
 | NanoCocktails-Using Lasers to Create Nanomaterials : DigInfo http://movie.diginfo.tv DigInfo News At NanoTech 2008, Laser Zentrum Hannover presented a range of micro and submicro structures, created by placing a solid material such as a metal, in a liquid and using short-pulsed lasers to break up the material into nanoparticles. Interview: "I'm from the laser center in Hannover, which is one of the biggest laser research institutes in the world, and we are focusing on nanotechnology using lasers. We use lasers to ablate materials in a liquid, this sounds strange but its quite easy, so the laser beam transmits the liquid and in the liquid there is a material which we make nanoparticles from. The liquid can be also a monomer. A monomer is a liquid out of which plastics are made. One example is this Nano Cocktail, we call it "Nano On The Beach". We call it a Nano Cocktail because this contains a cocktail of nano functions without changing the plastic, so you can use a standard plastic like what mobile phones or toys are made from with a standard procedure and put nanoparticles into this plastic by laser ablation. Then you can mould the plastic, then you have this part, its injection moulded, three dimensional and you can make it with standard technology. To summarize, we have patented a very simple process, in order to bring nano into end products without maing complicated changes to the process chain, we are just changing the raw material by using lasers." Embedding nanoparticles into polymer based materials can enhance a range of properties such as hardness, light absorption, biocompatibility, water repulsion, or optical properties. |
 | foam slicer- 6000 euros EASTFIELD FOAM MACHINE INDUSTRIAL LIMITED (china) Add: xiansha industrial zone ,gaobu town ,dongguan ,canton , china Tel : 86-769-88415199 fax :86-769-81300754 Homepage :www.foammachine-home.com Commonly abbreviated PU is any polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by reacting a monomer containing at least two isocyanate functional groups with another monomer containing at least two alcohol groups in the presence of a catalyst. Polyurethane formulations cover an extremely wide range of stiffness, hardness, and densities. These materials include low density flexible foam used in upholstery and bedding, low density rigid foam used for thermal insulation, soft solid elastomers used for gel pads and print rollers, and hard solid plastics used as electronic instrument bezels and structural parts. Polyurethanes are widely used in high resiliency flexible foam seating, rigid foam insulation panels, microcellular foam seals and gaskets, durable elastomeric wheels and tires, electrical potting compounds, high performance adhesives and sealants, Spandex fibers, seals, gaskets, carpet underlay, and hard plastic parts. Polyurethane products are often called "urethanes". They should not be confused with the specific substance urethane, also known as ethyl carbamate. Polyurethanes are not produced from ethyl carbamate, nor do they contain it. |
 | Jake's Attic - Making Nylon Thread A thread of nylon polymer is made using the monomer and acid in this science demonstration. |
 | Making a Model Organism Database Part 2F The "Making a Model Organism Database" webinar walks you through the process of building a Pathway Tools Pathway/Genome Database from an annotated genome file all the way through to the final product. In Part 2F, we round out our coverage of protein editing by showing you how to make protein complexes, and how to move reactions from one protein to another (for example, from a monomer to a multimer). |
 | Vinyl Chloride and Occupational Cancer After WWII, vinyl chloride (VC) became a key chemical used to make plastic products. It was manufactured exclusively for polymeri After WWII, vinyl chloride (VC) became a key chemical used to make plastic products. It was manufactured exclusively for polymerization into polyvinyl chloride (PVC), a plastic used in construction, packaging, electrical, and transportation industries; in household products such as flooring, water piping, videodiscs, and credit cards; and in medical products such as disposable intravenous bags, tubing, and bedpans. In 1974-1975, the disclosure that vinyl chloride exposure had caused rare liver cancers in worker led the recently created U.S. Occupational Safety and Health Administration (OSHA) to issue an emergency standard to ptotect workers. VC and PVC production plants had to reduce workplace exposure levels from 500 ppm to 1 ppm, to provide protect workers' health. When OSHA issued the new exposure limit of 1 ppm, industry spokespeople issued dire predictions of job loss and plant closures. However, in less than two years virtually all U.S. manufacturing plants were able to meet the new standard while still maintaining rapid growth of sales volume. This was accomplished largely through better containment of unpolymerized VC monomer and improved exposure monitoring. For more information, go to the 2005 article in the Journal Environmental Health Perspectives at http://www.ehponline.org/members/2005/7716/7716.html and read the book, Deceit and Denial: the deadly politics of industrial pollution by Markowitz and Rosner, from the University of California Press, http://www.ucpress.edu/books/pages/9844/9844.intro.html . This clip is from the 1978 movie, More Than a Paycheck, and the voice is the late Dr. Irving Selikoff. |
 | Fire snake monomer + syringe + matchbox + 3 bored interns at maranakatte = FIRE SNAKE |
 | Stefu Walk walking like Stefu sö schlendrian! |
 | Dogfight A dogfight... for fun. |
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