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This research is one of the largest studies of biodiesel in both on-road and off-road uses. The testing was conducted for the military and encompassed a wide range of application types including two medium-duty trucks, two Humvees, a heavy heavy-duty diesel truck, a bus, two stationary backup generators (BUGs), a forklift, and an airport tow vehicle. The full range of fuels tested included a California ultra-low sulfur diesel (ULSD) fuel, different blend ratios of two different yellow-grease biodiesels and one soy-based biodiesel, JP-8, and yellow-grease biodiesel blends with two different NOx reduction additives. The B20-YGA, B20-YGB, and B20-Soy did not show trends relative to ULSD that were consistent over all applications tested. Higher biodiesel blends were tested on only one vehicle, but showed a tendency for higher total hydrocarbons (THC) and carbon monoxide (CO) emissions and lower particulate matter (PM) emissions. The JP-8 showed increases in THC and CO relative to the ULSD.  相似文献   

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The energy and nutrient content of most agricultural crops are as good as or superior to natural foods for wild geese and they tend to be available in agricultural landscapes in far greater abundance. Artificial grasslands (fertilised native swards and intensively managed reseeds) offer far superior quality forage and higher intake rates than seminatural or natural grasslands. The availability of such abundant artificial food explains the abandonment of traditional habitats for farmland by geese over the last 50–100 years and favours no reduction in current levels of exploitation of agriculture. Continental scale spatial and temporal shifts among geese undergoing spring fattening confirm their flexibility to respond rapidly to broadscale changes in agriculture. These dramatic changes support the hypothesis that use of agricultural landscapes has contributed to elevated reproductive success and that European and North American farmland currently provides unrestricted winter carrying capacity for goose populations formerly limited by wetlands habitats prior to the agrarian revolution of the last century.  相似文献   

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Siikamäki J  Newbold SC 《Ambio》2012,41(Z1):78-89
Deforestation is the second largest anthropogenic source of carbon dioxide emissions and options for its reduction are integral to climate policy. In addition to providing potentially low cost and near-term options for reducing global carbon emissions, reducing deforestation also could support biodiversity conservation. However, current understanding of the potential benefits to biodiversity from forest carbon offset programs is limited. We compile spatial data on global forest carbon, biodiversity, deforestation rates, and the opportunity cost of land to examine biodiversity conservation benefits from an international program to reduce carbon emissions from deforestation. Our results indicate limited geographic overlap between the least-cost areas for retaining forest carbon and protecting biodiversity. Therefore, carbon-focused policies will likely generate substantially lower benefits to biodiversity than a more biodiversity-focused policy could achieve. These results highlight the need to systematically consider co-benefits, such as biodiversity in the design and implementation of forest conservation programs to support international climate policy.  相似文献   

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Environmental Science and Pollution Research - Agricultural soil acts as a source and sink of important greenhouse gases (GHGs) like methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2)....  相似文献   

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Because of the continuous production of large amount of waste tires, the disposal of waste tires represents a major environmental issue throughout the world. This paper reports the utilization of waste tires (hard-to-dispose waste) as a precursor in the production of activated carbons (pollution-cleaning adsorbent). In the preparation of activated carbon (AC), waste rubber tire (WRT) was thermally treated and activated. The tire-derived activated carbon was characterized by means of scanning electron microscope, energy-dispersive X-ray spectroscopy, FTIR spectrophotometer, and X-ray diffraction. In the IR spectrum, a number of bands centred at about 3409, 2350, 1710, 1650, and 1300–1000 cm?1 prove the present of hydroxyl and carboxyl groups on the surface of AC in addition to C═C double bonds. The developed AC was tested and evaluated as potential adsorbent removal of chromium (III). Experimental parameters, such as contact time, initial concentration, adsorbent dosage and pH were optimized. A rapid uptake of chromium ions was observed and the equilibrium is achieved in 1 h. It was also found that the adsorption process is pH dependent. This work adds to the global discussion of the cost-effective utilization of waste rubber tires for waste water treatment.  相似文献   

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Activated carbons (ACs) were developed from bio-waste materials like rice husk and peanut shell (PS) by various physicochemical activation methods. PS char digested in nitric acid followed by treatment at 673 K resulted in high surface area up to ~585 m2/g. The novelty of the present study is the identification of oxygen functional groups formed on the surface of activated carbons by infrared and X-ray photoelectron spectroscopy and quantification by using temperature programmed decomposition (TPD). Typical TPD data indicated that each activation method may lead to varying amounts of acidic and basic functional groups on the surface of the adsorbent, which may be a crucial factor in determining the adsorption capacity. It was shown that ACs developed during the present study are good adsorbents, especially for the removal of a model textile dye methylene blue (MB) from aqueous solution. As MB is a basic dye, H2O2-treated rice husk showed the best adsorption capacity, which is in agreement with the acidic groups present on the surface. Removal of the dye followed Langmuir isotherm model, whereas MB adsorption on ACs followed pseudo-second-order kinetics.  相似文献   

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《Chemosphere》1996,32(7):1427-1434
Dimethyl disulfide, dimethyl trisulfide, aliphatic alcohols, ketones, esters, thioesters, and isopreniods (C10, C11, C12, C15) were identified from the growth on a laboratory substrate of 7 isolates of actinomycetes, some of which have been associated with farmer's lung.  相似文献   

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The production of brominated aromatics from combustion was shown to be influenced by the operating conditions. Brominated aromatics also showed high yields compared to their chlorinated analogues.  相似文献   

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