Chemistry
People concerned about human-insecticide exposure have stimulated interest in alternative bed bug control materials, including oil-based pesticides and detergent insecticides.
But how well do they work? Researchers from Rutgers University evaluated the efficacy of nine essential oil-based products and two detergents that are labeled and marketed as 'natural' bed bug control.
The non-synthetic bed bug pesticides contain ingredients such as geraniol, rosemary oil, mint oil, cinnamon oil, peppermint oil, eugenol, clove oil, lemongrass oil, sodium lauryl sulfate, 2-Phenethyl propionate,…
Winners of the Nobel Prize in chemistry: Eric Betzig, Stefan Hell and William Moerner. Credit: Matt Staley, HHMI / Bernd Schuller, Max-Planck-Institut / K. Lowder
By Mark Lorch, University of Hull
Robert Hooke was a pioneer of microscopy, when back in the 17th century he drew stunning images of insects, plant cells and fossils. Since then microscopes that use light to magnify things we can’t see with the naked eye have, of course, improved. But, surprisingly, 300 years of engineering lenses hasn’t improved things all that much.
There happens to be a fundamental limit on the magnification that…
The Royal Swedish Academy of Sciences has awarded the 2014 Nobel Prize in Chemistry to Eric Betzig of Janelia Research Campus, Howard Hughes Medical Institute, Stefan W. Hell of the Max Planck Institute for Biophysical Chemistry and William E. Moerner of Stanford University “for the development of super-resolved fluorescence microscopy”.
Optical microscopy was once held back by a limitation: that it could never obtain a better resolution than half the wavelength of light. Helped by fluorescent molecules the Nobel Laureates in Chemistry 2014 ingeniously circumvented this limitation and…
Scientists have time detected a carbon-bearing molecule with a "branched" structure in interstellar space.
The molecule, iso-propyl cyanide (i-C3H7CN), was discovered in the giant gas cloud Sagittarius B2, a region of ongoing star formation close to the center of our galaxy that is a hot-spot for molecule-hunting astronomers.
The branched structure of the carbon atoms within the iso-propyl cyanide molecule is unlike the straight-chain carbon backbone of other molecules that have been detected so far, including its sister molecule normal-propyl cyanide. The discovery of iso-propyl cyanide…
If good things come in small packages, then nanoparticles are going to make engineers very happy.
The National Institute of Standards and Technology (NIST) recently issued Reference Material (RM) 8027, the smallest known reference material ever created for validating measurements of these man-made, ultra-fine particles between 1 and 100 nanometers (billionths of a meter) in size.
RM 8027 consists of five hermetically sealed ampoules containing one milliliter of silicon nanoparticles—all certified to be close to 2 nanometers in diameter—suspended in toluene.
To yield the appropriate sizes…
Earth's atmosphere is a complicated dance of molecules involving the output of plants, animals and human industry in sequences of chemical reactions.
Such processes help maintain the atmosphere's chemical balance; most topically during protest week in New York City, they break down pollutants emitted from the burning of fossil fuels.
Understanding exactly how these reactions proceed is critical for predicting how the atmosphere will respond to environmental changes, but some of the steps of this dance are so quick that all of the molecules involved haven't been measured in the wild.
A…
The appeal of artificial photosynthesis, in which the electrochemical reduction of carbon dioxide is used to produce clean, green and sustainable fuels, is that we can turn an atmospheric byproduct into a renewable energy technology.
However, finding a catalyst for reducing carbon dioxide that is highly selective and efficient has proven to be a huge scientific challenge.
Peidong Yang, a chemist with Berkeley Lab's Materials Sciences Division, led a study in which bimetallic nanoparticles of gold and copper were used as the catalyst for the carbon dioxide reduction. The results…
Concrete is the world’s most-used construction material and thus a leading contributor to global warming, producing perhaps 10 percent of industry-generated greenhouse-gas emissions.
Industry is already reducing greenhouse emissions, such as by using more natural gas and less coal to generate cost-effective electricity, and a new suggests another low-impact way go green - reducing concrete emissions by more than half and getting a stronger, more durable material using science rather than rationing.
The findings come from the most detailed molecular analysis yet of the complex structure…
A 1997 Food and Drug Administration (FDA) rule allowed food manufacturers to use ingredients "generally regarded as safe," or GRAS, like vinegar and lots of other things, without needing approval all over again.
Food advocates say the current GRAS process allows substances into the food supply that might pose a health risk. How can safe products be risky?
The logic used by food safety advocates in implying safe products might be risky is worrisome - they contend that if industry has in-house experts making assessments, the assessments will be unethical. This thinking is a large reason why the…
Natural gas hydraulic fracturing - fracking - has been wonderful for CO2 emissions while keeping energy costs for poor people manageable but a few sites have been treating fracking wastewater and returning it to rivers.
A new study finds that this is just as risky as dumping any municipal treated wastewater back into rivers. As runoff, it is safe but it shouldn't be done in volume. In the case of fracking wastewater, existing facilities are not equipped to thoroughly deal with halides so until they are ready, it's simply better to use fracking wastewater for fracking.
Writing in…