(Press-News.org) CHESTNUT HILL, MA (June 28, 2012) – Harnessing the power of the sun has inspired scientists and engineers to look for ways to turn sunlight into clean energy to heat houses, fuel factories and power devices. While a majority of this research focuses on energy production, some researchers are looking at the potential uses of these novel solar technologies in other areas.
Boston College Assistant Professor of Chemistry Dunwei Wang's work with silicon nanowires and his related construct, Nanonets, has shown these stable, tiny wire-like structures can be used in processes ranging from energy collection to hydrogen-generating water-splitting.
Teaming up with fellow Boston College Assistant Professor of Chemistry Kian L. Tan, the researchers have taken aim at a role for nanowires in photosynthesis.
Their work has produced a process that closely resembles photosynthesis, employing silicon nanowires to collect light energy to power reactions capable of synthesizing the basic compounds of two popular pain-killing, anti-inflammatory drugs, they report in the current edition of Angewandte Chemie, the journal of the German Chemical Society.
The reaction sequence offers an approach that differs from earlier attempts to sequester carbon dioxide with sunlight and solves the vexing problem of carbon's low selectivity, which so far has limited earlier methods to the production of fuels. Tan and Wang report their process offers the selectivity required to produce complex organic intermediaries capable of developing pharmaceuticals and high-value chemicals.
The process succeeds in taming stubborn carbon, which structurally resists most efforts to harness it for a single chemical product. Typically, refined forms of carbon molecules must first be produced to produce the necessary results.
"If we can start to use carbon dioxide and light to power reactions in organic chemistry, there's a huge benefit to that. It allows you to bypass the middle man of fossil fuels by using light to drive the chemical reaction," said Tan. "The key is the interaction of two fields – materials and synthetic chemistry. Separately, these fields may not have accomplished this on their own. But together, we combined our knowledge to make it work."
During photosynthesis, plants capture sunlight and use this solar energy and carbon dioxide to fuel chemical reactions.
Tan and Wang used silicon nanowires as a photocathode, exploiting the wire's efficient means of converting solar energy to electrical energy. Electrons released from the atoms in the nanowires are then transferred to organic molecules to trigger chemical reactions.
In this case, the researchers used aromatic ketones, which when struck by electrons become active and attack and bind carbon dioxide. Further steps produced an acid that allowed the team to create the precursors to ibuprofen and naproxen with high selectivity and high yield, the team reports.
Tan and Wang were joined in the research by Research Assistant Guangbi Yuan, PhD '12, graduate student Rui Liu, doctoral student Candice L. Joe, and former doctoral student Thomas E. Lightburn, PhD '11.
Tan said it is no accident that the process so closely resembles natural photosynthesis, as chemists are constantly drawing inspiration from nature in their work.
"Researchers in my field are always drawing inspiration from nature," said Tan. "You take the basic lessons and you try to do it in an artificial way. In this work, we're trying to learn lessons from nature, although we can't copy nature directly."
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Archaeologists working at the site of La Corona in Guatemala have discovered a 1,300-year-old-year Maya text that provides only the second known reference to the so-called "end date" of the Maya calendar, December 21, 2012. The discovery, one of the most significant hieroglyphic finds in decades, was announced today at the National Palace in Guatemala.
"This text talks about ancient political history rather than prophecy," says Marcello A. Canuto, director of Tulane's Middle American Research Institute and co-director of the excavations at La Corona.
Since 2008, Canuto ...
Training sessions for Team GB's swimmers have been getting a helping hand from a new system incorporating cutting-edge movement tracking and sensor technologies.
From starting dives to tumble turns the state-of-the-art coaching aid is the first of its kind to be able to track movement wirelessly through water.
The system has been developed at Loughborough University's Sports Technology Institute in conjunction with British Swimming, with funding from the Engineering and Physical Sciences Research Council (EPSRC). Other partners are UK Sport, Imperial College London ...
DURHAM, N.C. -- Clergy's practice of putting others first can be detrimental to their own health, say researchers at Duke University.
Pastors have been found to have higher-than-average rates of chronic disease and depression. But it may be difficult to get pastors to seek care because they typically default to caring for others first.
Duke researchers have been trying to design health programs that will be more effective for clergy, given these tendencies.
"Clergy recognize the importance of caring for themselves, but doing so takes a back seat to fulfilling their ...
Transplanting previously frozen ovarian tissue back into female cancer survivors can lead to long-term hormonal function and preservation of fertility, according to a new study by Samuel Kim from the University of Kansas Medical Center in the US. His work¹, which shows that hormonal function was restored in five women 12-20 weeks after transplantation, and in one case lasted for more than seven years, appears online in the Journal of Assisted Reproduction and Genetics², published by Springer.
Many female cancer patients want to remain fertile, and choose to freeze some ...
URBANA -- Steve Moose, an associate professor of maize functional genomics at the University of Illinois and his graduate student Wes Barber think they may have discovered a new source of heterosis, or hybrid vigor, in maize. They have been looking at small RNAs (sRNAs), a class of double-stranded RNA molecules that are 20 to 25 nucleotides in length.
"Hybrid vigor" refers to the increased vigor or general health, resistance to disease, and other superior qualities arising from the crossbreeding of genetically different plants. "We've always known that there's a genetic ...
Athens, Ga. – Weedy plants, many introduced to the U.S. for sale through plant nurseries, are responsible for extensive environmental damage and economic costs. Although legislation restricts the introduction of certain species, the procedures used to select species for inclusion on the restricted list are haphazard and out of date.
To meet the need for more systematic weed risk analysis, researchers at the University of Georgia Odum School of Ecology and the University of California, Davis have developed a "cost-sensitive" model to determine when importing a given plant ...
CHICAGO --- Today's senior citizens are reporting fewer visual impairment problems than their counterparts from a generation ago, according to a new Northwestern Medicine study. Improved techniques for cataract surgery and a reduction in the prevalence of macular degeneration may be the driving forces behind this change, the researchers said.
"From 1984 until 2010, the decrease in visual impairment in those 65 and older was highly statistically significant," said Angelo P. Tanna, M.D., first author of the study. "There was little change in visual impairments in adults ...
CERN, the European Organization for Nuclear Research headquartered in Geneva, Switzerland, will hold a seminar early in the morning on July 4 to announce the latest results from ATLAS and CMS, two major experiments at the Large Hadron Collider (LHC) that are searching for the Higgs boson. Both experimental teams are working down to the wire to finish analyzing their data, and to determine exactly what can be said about what they've found.
"We do not yet know what will be shown on July 4th," says Ian Hinchliffe, a theoretical physicist in the Physics Division at the U.S. ...
For the first time comparable migration data is available for almost every country of the world. To date, records were incompatible between nations and especially by gender and age, nonexistent. Emilio Zagheni from the Max Planck Institute for Demographic Research (MPIDR) in Rostock, Germany, for the first time provides a rich migration database by compiling the global flow of millions of e-mails.
"Where estimates of demographic flows exist, they are often outdated and largely inconsistent," says MPIDR researcher Emilio Zagheni. Official records are difficult to use for ...
Researchers at the Hollings Marine Laboratory (HML) and four partner organizations have measured for the first time concentrations of 13 perfluoroalkyl compounds (PFCs) in five different endangered species of sea turtles. While PFC toxicology studies have not yet been conducted on turtles, the levels of the compounds seen in all five species approach the amounts known to cause adverse health effects in other animals.
PFCs are man-made compounds that have many uses including stain-resistant coatings, fire-fighting foams and emulsifiers in plastics manufacturing. They have ...
