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Free-standing aligned carbon nanotubes have previously been grown above 700 degreesC on mesoporous silica embedded with iron nanoparticles. Here, carbon nanotubes aligned over areas up to several square centimeters were grown on nickel-coated glass below 666 degreesC by plasma-enhanced hot filament chemical vapor deposition. Acetylene gas was used as the carbon source and ammonia gas was used as a catalyst and dilution gas. Nanotubes with controllable diameters from 20 to 400 nanometers and lengths from 0. 1 to 50 micrometers were obtained. Using this method, large panels of aligned carbon nanotubes can be made under conditions that are suitable for device fabrication.  相似文献   
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Weeds caused serious problem on yield reduction of basmati rice worldwide. Losses caused by weeds varied from one country to another, depending on the presence of dominant weeds and the control methods practiced by farmers; therefore, suitable plant population and weed management practices should be adopted. Keeping these in mind, a field experiment was carried out during kharif seasons of 2009 and 2010 at crop Research Centre of SVPUA&T, Meerut, India comprising 4 planting geometries, viz. 20, 30, 40, and 50 hills m?2 as main plot factor, and 5 weed management practices (Butachlor @ 1.0 kg ha?1, Butachlor @ 1.0 kg ha?1 fb (followed by) one hand weeding, Butachlor @ 1.0 kg ha?1 fb Almix @ 4 g ha?1, two hand weedings and weedy check) in a split plot design with 3 replications. Experimental results revealed that plant population of 50 hills m?2 proved superior over that of 20 hills m?2 in respect of weed density, weed dry weight, number of tillers m?2, yield attributes, grain, straw, and biological yields. The maximum grain yield (29.00 and 31.00 q ha?1) and straw yield (51.30 and 52.50 q ha?1) were recorded in 50 hills m?2 followed by 40 hills m?2 during 2009 and 2010, respectively. In respect of nitrogen, phosphorus, and potassium removal, a reverse trend was observed: the highest in 20 hills m?2 followed by 30, 40, and 50 hills m?2. As far as the weed management practices are concerned, both chemical and mechanical methods of weed control were found superior over weedy check. The lowest weed density, dry weight, and highest weed control efficiency, maximum length of panicle?1, number of panicle (m2), and 1000-grain weight and grain yield of 30.40 and 32.60 q ha?1 were recorded with two hand weedings which was at par with Butachlor @ 1.0 kg ha?1 fb one hand weeding over rest of the weed management practices.  相似文献   
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Summary A study of the several interspecific and inter-subspecific crosses indicated that albinism in groundnut is recessive and in these crosses is controlled by triplicate recessive loci.ICRISAT Paper No. JA-336  相似文献   
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Ultrastructural changes are reported in the kidney and liver of 20-day-old broiler chicks fed ochratoxin A (OA), incorporated in the diet at levels of 2 and 4 ppm. Changes in the kidney included the presence of abnormally shaped mitochondria in the proximal convoluted tubules. There was an increase in the size and number of mitochondrial dense granules and cytoplasmic peroxisomes. Intranuclear and cytoplasmic lipid droplets and electron dense round bodies in the dilated smooth endoplasmic reticulum were also noted. Regional thickening and degeneration of the glomerular basement membrane was observed in some cases. In the liver from OA fed birds there was an increased accumulation of cytoplasmic glycogen in the hepatocytes. Abnormal mitochondrial ring forms in the kidney and the accumulation of glycogen in the liver are considered to be of diagnostic significance in ochratoxicosis of young broiler chicks. The severity of the changes was found to be dose related. These results suggest that the mitochondria in the proximal convoluted tubules of kidney were most sensitive to OA toxicity.  相似文献   
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Ultrathin sections of liver and kidney from 11-week-old quail fed, from day-old, ochratoxin A (OA) (mixed in the diet at levels of 4 and 8 ppm) were examined in the electron microscope. Pathological changes in the kidneys were limited to the proximal convoluted tubules (PCT) and glomeruli. In the PCTs, abnormal mitochondria and excessive numbers of lipid droplets were the principal findings with glomeruli showing thickened basement membranes. Swollen mitochondria and variable glycogen deposition were the chief features present in the livers. It is suggested that OA is more hepatotoxic in quail than in broilers, as well as being nephrotoxic.  相似文献   
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The perception of Rwandan government officials, NGOs, and extension specialists about smallholder agroforestry adoption as a strategy for smallholder farmers in Rwanda was investigated using a strengths, weaknesses, opportunities, and threats analysis framework combined with the analytical hierarchy process. Results indicate that smallholder agroforestry is viewed positively as a suitable strategy for Rwandan smallholder farmers. The most important positive features were the potential for increased agricultural output from agroforestry and a favorable policy environment in Rwanda supporting sustainable agriculture. Results also indicate that there needs to be better coordination of various efforts to promote agroforestry and stronger extension services for smallholder farmers. Carbon offset markets and other environmental service markets were seen as a potential opportunity for smallholder agroforestry. However, the results also indicate that there is substantial uncertainty and skepticism concerning how such markets would benefit smallholder farmers who adopted agroforestry.  相似文献   
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