Because of their high viscosity and density, crude fats and oils extracted from animal or vegetable sources (containing mainly triglycerides) cannot be directly combusted in modern diesel engines; therefore,
Carbon supported platinum is commonly used as anode and cathode electrocatalyst in low-temperature fuel cells fuelled with hydrogen or low molecular weight alcohols. The cost of Pt and the limited world supply are significant barriers to the widespread use of these types of fuel cells. Moreover
Typical microbial fuel cells (MFCs) rely on precious metals for reduction of oxygen at the cathode, but recently MFCs have been developed that use biocathodes for power generation with alternate electron acceptors.
Harvesting electricity from the environment, organic wastes, or renewable biomass with microbial fuel cells (MFCs) is an appealing strategy, but the destructive sampling required to investigate the anode-associated biofilms has hampered research designed to better understand and optimize microbe–anode interactions.
Since the early development of this technology in the 1970s, TiO2 constitutes the archetypical photocatalyst due to its relatively high efficiency, low cost and availability. However, during the last decade a considerable number of new photocatalytic materials
In this study, we fabricated inverted polymer solar cells featuring titanium dioxide (TiO2) as the electron collection layer and vanadium (V) oxide (V2O5) as the hole collection layer. TiO2 films (anatase phase) were prepared by combining electrochemical deposition with high-pressure crystallization. The low temperature process used to obtain the TiO2 films minimized interdiffusion of Ti and In species between the TiO2 and ITO films and maintained the conductivity of the indium tin oxide substrate. The inverted device reached a power conversion efficiency of 3.22% and exhibited much better stability under ambient conditions relative to that of the corresponding conventional device.
Green Chemistry for Fuels of the Future will remain a great challenge and also a rewarding experience to chemists and engineers worldwide. This themed issue is the first one in the journal Energy & Environmental Science.
Low-fat milk, 100-percent juices, and bottled water are the new recommended beverages for school meal programs and vending machines.
But other health experts intend to keep fighting for tap water.
"There's more demand for bottled water now in schools, and the beverage industry says they have public health in mind," Yale's Brownell said. "But we're hoping to do a big campaign to encourage consumption of tap water instead."
When that happens, "they never go to the California beach, but they do go to the Hawaiian Islands," Maximenko said. Pieces that don't wind up in Hawaii eventually cycle back into the Pacific garbage patch.
Drifters deployed in the Atlantic show a similar system of currents in the newfound garbage patch, the researchers said, which means pieces could be escaping when those currents shift.
Overall, the Sea Education Association's Proskurowski said, finding plastic so far out in either ocean is sobering, because "it forces us into physical confrontation with the human impact on the environment."
By speeding up Earth's rotation, the magnitude 8.8 earthquake—the fifth strongest ever recorded, according to the USGS—should have shortened an Earth day by 1.26 millionths of a second, according to new computer-model calculations by geophysicist Richard Gross of NASA's Jet Propulsion Laboratory in California.
For comparison, the same model estimated that the magnitude 9 Sumatra earthquake in December 2004 shortened the length of a day by 6.8 millionths of a second.
(See Chile earthquake pictures.)
Gross also estimates that the Chile earthquake shifted Earth's figure axis by about three inches (eight centimeters).
Deviating roughly 33 feet (10 meters) from the north-south axis around which Earth revolves, the figure axis is the imaginary line around which the world's unevenly distributed mass is balanced.
To explain the difference, Keith Sverdrup, a seismologist at the University of Wisconsin-Milwaukee, likened Earth to a spinning figure skater holding a rock in one hand. The rotational axis of the skater is still down the middle of the body, he said, but the skater's figure axis is shifted slightly in the direction of the hand holding the rock.
In an effort to encourage breeding in a critically endangered frog, scientists at the San Diego Zoo's Institute for Conservation Research have placed 24 mountain yellow-legged frogs into refrigerators.
hoto courtesy of West Virginia Division of Natural Resources
Last November, the Smithsonian's National Zoo accepted 40 endangered Virginia big-eared bats (Corynorhinus townsendii virginianus) to establish a security population and scientifically develop husbandry practices--a feat no one else has undertaken with this subspecies, the zoo said in a recent news statement.
"In the months since, efforts to keep the bats alive have proved challenging, but the lessons Zoo scientists have learned will help save these, and other, insectivorous bats in the future," the zoo said.
The U.S. Fish and Wildlife Service funded this and other research projects focused on white-nose syndrome and bat survival. The West Virginia Division of Natural Resources assisted with the project.
The bat colony has been living at the Smithsonian Conservation Biology Institute in Front Royal, Virginia. "The possible extinction of an endangered subspecies, and the loss of its essential role in local ecosystems, were the reasons the National Zoo accepted the high-risk project," the zoo said.
"Over the past four months, the majority of the bats have died; 11 bats remain in the National Zoo's colony," the zoo added.
"The initial challenge the team faced was how to feed the animals.
"Virginia big-eared bats, which are a subspecies of the Townsend's big-eared bat (Corynorhinuss townsendii), eat on the wing (in flight).
"While some in the security colony successfully learned to eat mealworms out of pans, others did not, sometimes resulting in their death.
"Some of the bats that ate mealworms did not adequately groom themselves, which resulted in dermatitis (inflammation of the skin). Others developed foot, toe and digit problems that, in part, may have caused deadly bacterial infections that spread rapidly through the blood stream despite aggressive treatments with antibiotics and fluids."
"Virginia big-eared bats face an imminent threat from white-nose syndrome," said the U.S. Fish and Wildlife Service's National White-Nose Syndrome Coordinator Jeremy Coleman. "Developing a successful captive breeding program is a reasonable precautionary step to ensuring the long-term viability of the subspecies. The Smithsonian's National Zoo was the only organization to accept the challenge of this risky, groundbreaking, but essential endeavor."
Examining Virginia big-eared bats.
Photo courtesy of West Virginia Division of Natural Resources
Because it is extraordinarily difficult to maintain insect-eating bats in captivity, extensive planning and preparations went into designing the project, the zoo said.
The zoo formed a bat care team made up of biologists, husbandry and animal care specialists, veterinarians, and a nutritionist who relied on protocols developed by the Virginia Big-Eared Bat Group convened by FWS. "The SCBI team worked around the clock to care for, and learn from, the colony," the zoo said.
"We expected some of the feeding challenges," said David Wildt, head of the National Zoo's Species Survival Center. "But we were surprised to learn how sensitive this particular subspecies of bat is. Even the smallest change in environment or husbandry practices seemed to affect the ability of the bats to adapt to their new environment."
National Zoo researchers found that bats learned to eat from the bowl faster when confined in a small enclosure for a few hours. In the future, the zoo said, scientists could use this information to better provide for the needs of the subspecies in captivity. "The bat team learned a great deal about enclosures and medical care required for insectivorous bats in captivity."
"Faced with the possibility of white-nose syndrome eliminating the entire subspecies, we took decisive action to attempt to protect the bats," Coleman said. "Together with the Zoo, we will examine this project, take what we have learned and be ready to apply it to captive propagation projects in the future."
White-nose syndrome continues to devastate wild bat colonies. The fungus is now present in caves in West Virginia that support the largest hibernating populations of Virginia big-eared bats in the world. It has spread to 10 states, from New Hampshire to Tennessee, and more endangered bat species are now within its range.
Some tuna-fishing countries, notably Japan, are reported by various news organizations to be opposed to the proposed trade ban on bluefin tuna. Japan, it is said, will lodge reservations about the listing and will defy it if it is passed.
If chlorine is present, this nighttime removal process doesn't occur, and the nitrogen oxides can be regenerated in the morning, when the sun rises and rush hour traffic adds more pollutants to the air.
Atmospheric chlorine may also enhance the production of ozone, a key ingredient of smog that is potentially toxic to animal and plant life, Thornton said. But chlorine may also reduce the concentration of certain global warming-causing greenhouse gases, such as methane.
The magnitude 5.9 temblor hit Elazig Province (see map) in the predawn hours, destroying stone and mud-brick houses and minarets in at least six villages, according to the Associated Press.
Though the Turkey earthquake closely follows deadly temblors in Haiti (see Haiti earthquake pictures) and Chile (see Chile earthquake pictures), the three seismic events are too distant geographically to be related, seismologist Bernard Doft, of the Royal Netherlands Meteorological Institute in Utrecht, told AP.
Published March 8, 2010
Plans to use concentrating solar power plants in the Sahara to generate and export electricity have been on the table for years. Now, it looks as though political will might help move things forward
The logic of the idea would seem obvious to a child: the human race needs to wean itself off fossil fuels, so why don't we build solar power plants in the world's deserts, to give us all the energy we need?
Many areas of the US have high background radon levels in the ground. When radon gets into a home it can increase the resident's cancer risk. How does radon get into a home? The most common way is through cracks in basement floors, walls, and sump pump sumps. In the winter, if a furnace or boiler is in the basement, the chimney can act as a depressurization device since combustion air is vented to the outdoors. If the basement is tight, and there is no source of combustion air, the heating system (and water heater too) can depressurize the basement. If there is radon in the soil gas below the house, this depressurization will increase radon infiltration through cracks and sumps. Another infiltration route is through groundwater. In areas with elevated radon in rock formations, and in homes using on-site wells for water, the water carries radon into the shower where it vaporizes to gaseous radon.
There are no authoritative figures on the international ownership of ski homes but between 2004 and 2007, around 70% of all flats and chalets sold in one large resort in the French Alps were bought by Britons, and dozens of British estate agents market ski properties in Europe and North America. Now they — and the developers behind the resorts — are trying to avoid this lucrative market being consigned to history.
Electric cars have many merits: They are quieter and require less maintenance than cars with internal combustion engines. A network of smartly located charging stations covering the entire Harz region in Germany is designed to make electric cars a regional feature.
Climbing beans suited to rainy high-altitude areas are being distributed in Rwanda after a decade of research.
The fifteen varieties, developed by the Rwandan Agricultural Research Institute (ISAR) in collaboration with the International Center for Tropical Agriculture (CIAT), could benefit smallholder farmers in similar areas across Central and East Africa.
Climate change has affected Kenyan coffee production through unpredictable rainfall patterns and excessive droughts, making crop management and disease control a nightmare, a researcher said on Thursday.
Intermittent rainfall in the 2007/08 crop year, for example, caused a terrible bout of the Coffee Berry Disease that cut Kenyan output 23 percent to 42,000 metric tons as farmers were caught out by rains and did not protect their crop in time.
U.S. farmers grew record-large corn and soy crops in 2009 but production in 2010 could be even bigger, aided by an El Nino weather pattern that is typically a boon to the Midwest but less so for growers in Australia and southeast Asia, a forecaster said on Thursday.
Allen Motew, meteorologist at QT Weather, forecast a dry U.S. spring, which should minimize problems at planting time, followed by a favorably wet summer growing season.
"It's exactly what we need to increase (crop) yields," Motew said at the Top Producer Seminar, a farmers' conference held in Chicago.
Carbon dioxide is the gas we most associate with global warming, but methane gas also plays an important role. For reasons that are not well understood, methane gas stopped increasing in the atmosphere in the 1990s. But now it appears to be once again on the rise. Scientists are trying to understand why — and what to do about it.
Methane gas comes from all sorts of sources including wetlands, rice paddies, cow tummies, coal mines, garbage dumps and even termites. Drew Shindell, at NASA's Goddard Institute in New York, says, "It's gone up by 150 percent since the pre-industrial period. So that's an enormous increase. CO2, by contrast, has gone up by something like 30 percent."
As Mongolia cowers under the brutal thrall of its worst winter in decades, questions are being asked as to whether the country should end its reliance on nomadic herders and dig deeper into its mineral reserves instead.
Overuse of nitrogen fertilisers in China is leading to rapid soil acidification and is causing lasting damage to ecosystems, according to soil study
Nitrogen fertilisers used to increase crop yields in China are having "extreme" environmental consequences, according to a study from leading soil scientists.
Children from several Latin American countries have traces of the pesticide DDT in their blood, according to a study coordinated by the Pan American Health Organization.
The children studied belong to 11 rural communities in Mesoamerica (Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama). In all but Guatemala, the researchers found exposure to DDT.
Malaria researchers in Benin say they may have found a replacement for DDT in areas where mosquitoes are resistant to common insecticides.
Indoor residual spraying (IRS) of insecticides is a major part of malaria control. But worries over toxicity and environmental persistence have led to calls for DDT to be phased out, and mosquitoes are growing resistant to widely used pyrethroid insecticides. Alternatives are expensive and short-lived.