June 18, 2006, 3:17 PM CT

When You Dump A Bucket Of Liquid Nitrogen

Ever wonder what happens when you dump a bucket of liquid nitrogen into a swimming pool?

Submitted by SchlockMercenary.com on 06/16/06.

Watch Video........

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June 18, 2006, 10:58 AM CT

Chemists Direct Silicon Oxide

Chemistry often seems to operate at random. However, researchers from the Max Planck Institute of Coal Research and the International Max Planck Research School "SurMat" have been able to change that: they grew silica particles from a solution onto a surface in such a way that a pattern of tiny little cones was regularly formed. Every silica cone was made of numerous spirals sitting on top of each other, and every spiral was made of tubes, in which the silica grouped itself around micelles of long-chain organic molecules. These kinds of selected hierarchical structures, which are exactly defined at large and small scales, were unknown to researchers except in nature, for example in bones, wood, and sea shells. Now, however, they can be grown in test-tubes - and that could allow engineers to produce even smaller optical and electronic components (Advanced Materials, April 18, 2006).

Bones are light and stable. That is because they are built optimally, at the smallest and largest levels. Their smallest elements are bound to fibrils, which fold together to make lamellae. These, in turn, organise themselves into girders that form a scaffolding, which has inspired even/also? structural engineers. Materials researchers call this kind of highly selected structure "hierarchical". Now, chemists from the Max Planck Institute of Coal Research in Mülheim an der Ruhr, Gera number of, have created a selected hierarchical structure from silica particles for the first time. It was made from a reaction solution in which very different forms of silica particles were able to grow. A silicon compound was mixed with an amine dragging a long tail of fatty acid. The amine molecules assemble micelles, which form long threads, and the silica accumulates on these threads. If the researchers dip an untreated support into the solution - for example, a lightly contaminated glass plate - the particles form random deposits: sometimes cone-shaped, sometimes a double cone, sometimes fibre-like shapes.........

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June 13, 2006, 11:43 PM CT

Chlorine May Contribute To Ozone Formation

Standard methods of predicting air pollution don't take atmospheric chlorine into account, but the chemical could be responsible for 10 percent or more of daily ozone production in local air, research at UC Irvine has found.

Air measurements taken nearly nonstop in the Irvine area over a two-month period showed that daytime chlorine gas levels typically measured five parts per trillion or less, but occasionally reached as high as 15 parts per trillion. Observation of daytime chlorine is surprising because chlorine molecules break apart just minutes after entering the atmosphere and being exposed to sunlight.

With these measurements, researchers estimate that chlorine photochemistry creates five to eight parts per billion of the maximum daily ozone level, which in California typically ranges between 40 and 80 parts per billion.

"Chlorine chemistry can have a direct impact on surface ozone even at parts per trillion levels," said Eric Saltzman, professor of Earth system science in the School of Physical Sciences at UCI. "Because of the strong link between ozone and human health, we need to fully understand the role chlorine may play in ozone chemistry in coastal urban environments."

Saltzman and Brandon Finley, a graduate student researcher in the Department of Earth System Science, published their findings in the current issue of Geophysical Research Letters.........

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May 25, 2006, 11:02 PM CT

Still More Accurate

Scientists at the National Institute of Standards and Technology (NIST) have developed an improved method for measuring basic properties of complex fuel mixtures like gasoline or jet fuel. The new apparatus for measuring distillation properties produces significantly more detailed and accurate data needed to better understand each fuel and its sample-to-sample variation. The data are valuable in tailoring fuels for high-performance and low emissions, and in designing new fuels, engines and emission controls.

Petroleum-based fuels, with few exceptions, are highly complex mixtures of hundreds of distinct components from light butanes to increasingly heavy oils. For decades, distillation curves have been one of the most widely accepted ways of characterizing a fuel. The curve charts the percentage of the total mixture that has evaporated as the temperature of a sample is slowly heated. The curve holds a wealth of information--not just the basic makeup of the fuel, but also indicators as to how it will perform. Engine starting ability, fuel system icing, vapor lock, fuel injection scheduling, fuel auto-ignition, hot- and cold-weather performance, and exhaust emissions all have been correlated with features of the distillation curve. The data are important both for quality control at refineries and the design of specialty high-performance fuels.........

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May 24, 2006, 0:10 AM CT

Tibet Pathway For Chemicals

Scientists from Georgia Tech and NASA have found that thunderstorms over Tibet provide a main pathway for water vapor and chemicals to travel from the lower atmosphere, where human activity directly affects atmospheric composition, into the stratosphere, where the protective ozone layer resides.

Learning how water vapor reaches the stratosphere can help improve climate prediction models. Similarly, understanding the pathways that ozone-depleting chemicals can take to reach the stratosphere is essential for understanding future threats to the ozone layer, which shields Earth from the sun's harmful ultraviolet rays.

Scientists from the Georgia Institute of Technology, Atlanta; NASA's Jet Propulsion Laboratory, Pasadena, Calif.; and the University of Edinburgh, Scotland, performed their analysis using data from the Microwave Limb Sounder instrument on NASA's Aura spacecraft, combined with data from NASA's Aqua and Tropical Rainfall Measuring Missions.

The team collected more than 1,000 measurements of high concentrations of water vapor in the stratosphere over the Tibetan Plateau and the Asian monsoon region. The measurements were collected during August 2004 and August 2005, during the height of monsoon season. Through the use of wind data and NASA atmospheric models, they found the water vapor originated over Tibet, just north of the Himalayan mountain range.........

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May 11, 2006, 0:10 AM CT

Home Testing Kit To Identify Hidden Caffeine

you've ever wondered whether your favorite coffee, tea or soda contains caffeine - despite its decaf label or the absence of caffeine on the ingredient list - then you may soon be able to test the beverage yourself. Chemists at Washington University School of Medicine in St. Louis are developing a quick, convenient "dipstick" test that they say could represent the first home testing kit to detect the common stimulant, which can cause insomnia and make you jittery. Their study will appear in the June 1 print issue of the American Chemical Society's Analytical Chemistry.

"We envisioned that a simple method to measure caffeine, even in hot beverages, such as coffee, would be of value to individuals and institutions wanting to verify the absence of caffeine," says study leader Jack H. Ladenson, Ph.D., a chemist at the university. "This will greatly assist individuals who wish to avoid caffeine".

Ladenson hopes to develop a simple caffeine test in which test strips that are treated with a specific antibody will react by changing color in the presence of caffeine.

The new test will be designed to be qualitative only: It allows a person to quickly determine whether caffeine is present, but does not indicate the exact amount or concentration of caffeine. In preliminary tests using coffee and cola, an experimental version of the test effectively distinguished caffeinated versions of these products from their decaf counterparts, Ladenson says.........

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May 9, 2006, 11:59 PM CT

Tibet Provides Passage For Chemicals

NASA and university scientists have found that thunderstorms over Tibet provide a main pathway for water vapor and chemicals to travel from the lower atmosphere, where human activity directly affects atmospheric composition, into the stratosphere, where the protective ozone layer resides.

Learning how water vapor reaches the stratosphere can help improve climate prediction models. Similarly, understanding the pathways that ozone-depleting chemicals can take to reach the stratosphere is essential for understanding future threats to the ozone layer, which shields Earth from the sun's harmful ultraviolet rays.

Scientists from the Georgia Institute of Technology, Atlanta; NASA's Jet Propulsion Laboratory, Pasadena, Calif.; and the University of Edinburgh, Scotland, performed their analysis using data from the Microwave Limb Sounder instrument on NASA's Aura spacecraft, combined with data from NASA's Aqua and Tropical Rainfall Measuring Missions.

The team collected more than 1,000 measurements of high concentrations of water vapor in the stratosphere over the Tibetan Plateau and the Asian monsoon region. The measurements were collected during August 2004 and August 2005, during the height of monsoon season. Through the use of wind data and NASA atmospheric models, they found the water vapor originated over Tibet, just north of the Himalayan mountain range.........

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May 7, 2006, 11:11 PM CT

Huge Impacts From Tiny Tech

The Center for Responsible Nanotechnology (CRN) today announced the continuation of its first series of original essays in which industry experts predict profound impacts of nanotechnology on society. Eleven new articles by members of CRN's Global Task Force appear in the latest issue of the journal Nanotechnology Perceptions, published recently, complementing the prior issue's collection. Covering topics from commerce to criminology, from ethics to economics, and from our remote past to our distant future, this new collection illustrates the profound transformation that nanotechnology will have on every aspect of human society.

Ray Kurzweil, renowned inventor, entrepreneur, and best-selling author, explained, "As the pace of technological advancement rapidly accelerates, it becomes increasingly important to promote knowledgeable and insightful discussion of both promise and peril. I'm very pleased to take part in this effort by including my own essay, and by hosting discussion of these essays on the 'MindX' discussion board at KurzweilAI.net".

Nanotechnology Perceptions is a peer-reviewed academic journal of the Collegium Basilea in Basel, Switzerland. "We jumped at the chance to publish the CRN Task Force essays," said Jeremy Ramsden, editor-in-chief of the journal. "To us, these articles represent world-class thinking about some of the most important challenges that human society will ever face."........

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May 7, 2006, 11:05 PM CT

How Does 'mechanochemistry' Work?

It's a bit like enzymes (if you know your chemistry): you fix onto a molecule or two, then twist or pull or push in a precise way until a chemical reaction happens right where you want it. This happens in a vacuum, so you don't have water molecules bumping around. It's a lot more controllable that way.

So, if you want to add an atom to a surface, you start with that atom bound to a molecule called a "tool tip" at the end of a mechanical manipulator. You move the atom to the point where you want it to end up. You move the atom next to the surface, and make sure that it has a weaker bond to the tool tip than to the surface. When you bring them close enough, the bond will transfer. This is ordinary chemistry: an atom moving from one molecule to another when they come close enough to each other, and when the movement is energetically favorable. What's different about mechanochemistry is that the tool tip molecule can be positioned by direct computer control, so you can do this one reaction at a wide variety of sites on the surface. Just a few reactions give you a lot of flexibility in what you make.........

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May 3, 2006, 10:36 PM CT

Chemists Assuring Quality Of Tequila

Whether you're celebrating Cinco de Mayo or just having another relaxing day in Margaritaville, you might one day thank a chemist for assuring the authenticity of your tequila. New tests developed by researchers in Mexico and Gera number of will help distinguish the real thing from fraudulent versions, which are a potential threat as this alcoholic beverage grows in popularity.

The findings could help provide a "shot" of quality assurance to the estimated billion-dollar tequila market, the scientists say. Their study is scheduled to appear in the June 14 issue of the American Chemical Society's Journal of Agricultural and Food Chemistry.

But there's no reason for consumers to panic, the scientists say. "Tequila is one of the best regulated spirits in the world with strict Mexican standards and labeling regulations," says study leader Dirk Lachenmeier, Ph.D., a chemist with Chemisches und Veterinäruntersuchungsamt Karlsruhe (Chemical and Veterinary Investigation Laboratory of Karlsruhe) in Gera number of. Thanks to advancements in chemistry, the quality of this ancient Mexican beverage can now be protected.

Tequila is made from the blue Agave plant and its production is limited to certain geographic areas, primarily to the state of Jalisco in West-Central Mexico. Eventhough it is subject to strict production standards and labeling regulations, adulterated samples have occasionally been reported, the scientists say. The exact percentage of fraudulent samples on the market is unknown, they add.........

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