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71.
BACKGROUND: Nanoemulsion composed of neem oil and non‐ionic surfactant Tween 20, with a mean droplet size ranging from 31.03 to 251.43 nm, was formulated for various concentrations of the oil and surfactant. The larvicidal effect of the formulated neem oil nanoemulsion was checked against Culex quinquefasciatus. RESULTS: O/W emulsion was prepared using neem oil, Tween 20 and water. Nanoemulsion of 31.03 nm size was obtained at a 1:3 ratio of oil and surfactant, and it was found to be stable. The larger droplet size (251.43 nm) shifted to a smaller size of 31.03 nm with increase in the concentration of Tween 20. The viscosity of the nanoemulsion increased with increasing concentration of Tween 20. The lethal concentration (LC50) of the nanoemulsion against Cx. quinquefasciatus was checked for 1:0.30, 1:1.5 and 1:3 ratios of oil and surfactant respectively. The LC50 decreased with droplet size. The LC50 for the ratio 1:3 nanoemulsions was 11.75 mg L?1. CONCLUSION: The formulated nanoemulsion of 31.03 nm size was found to be an effective larvicidal agent. This is the first time that a neem oil nanoemulsion of this droplet size has been reported. It may be a good choice as a potent and selective larvicide for Cx. quinquefasciatus. Copyright © 2011 Society of Chemical Industry  相似文献   
72.
A field experiment was conducted to investigate the effects of 1,2,3,4,5,6-hexachlorocyclohexane (BHC), phorate, carbofuran, and fenvalerate, at their recommended doses, on some chemical and microbiological properties of the rhizosphere soil in relation to rice yields. In general, the insecticides had a beneficial effect on rhizosphere soil properties. Carbofuran strongly stimulated the mineralization of organic C. BHC and phorate led to the retention of less total N in the soil. BHC released more NH inf4 sup+ -N than the other insecticides. Phorate, however, liberated the most NO inf3 sup- -N. Phorate and fenvalerate released more available P than BHC and carbofuran did. All the insecticides stimulated the proliferation of aerobic non-symbiotic N2-fixing and phosphate-solubilizing microorganisms, resulting in an overall increase in rice yield. BHC had the greatest effect on rice yields, followed by phorate.  相似文献   
73.
Sitostanol has been converted in high to near-quantitative extent to the corresponding long-chain acyl esters via esterification with oleic acid or transesterification with methyl oleate or trioleoylglycerol using immobilized lipases from Rhizomucor miehei (Lipozyme IM) and Candida antarctica (lipase B, Novozym 435) as biocatalysts in vacuo (20-40 mbar) at 80 degrees C, whereas the conversion was markedly lower at 60 and 40 degrees C. Corresponding conversions observed with papaya (Carica papaya) latex lipase were generally lower. High conversion rates observed in transesterification of sitostanol with methyl oleate at 80 degrees C using Lipozyme IM were retained even after 10 repeated uses of the biocatalyst. Saturated sterols such as sitostanol and 5alpha-cholestan-3beta-ol were the preferred substrates as compared to Delta(5)-unsaturated cholesterol in transesterification reactions with methyl oleate using Lipozyme IM. Transesterification of cholesterol with dimethyl 1,8-octanedioate using Lipozyme IM in vacuo yielded methylcholesteryl 1,8-octanedioate (75%) and dicholesteryl 1,8-octanedioate (5%). However, transesterification of cholesterol with diethyl carbonate and that of oleyl alcohol with ethylcholesteryl carbonate, both catalyzed by Lipozyme IM, gave ethylcholesteryl carbonate and oleylcholesteryl carbonate, respectively, in low yield (20%). Moreover, cholesterol was transesterified with ethyl dihydrocinnamate using Lipozyme IM to give cholesteryl dihydrocinnamate in moderate yield (56%), whereas the corresponding reaction of lanosterol gave lanosteryl oleate in low yield (14%).  相似文献   
74.
Genetic variation at 59 protein coding loci (16 polymorphic) and 25 microsatellite loci was analysed for 11 indigenous south-east Asian goat populations, and the Australian feral population, to determine the magnitude of genetic differentiation and the genetic relationships among the populations. Significant deviations from Hardy–Weinberg equilibrium were detected in one or more populations for eight of the nine protein loci with codominant alleles, and for microsatellites for all except the two Sri Lankan populations and for all but four loci. For both marker types, average inbreeding coefficients ( F IS) were exceptionally high. Heterogeneity of deviations from Hardy–Weinberg equilibrium for the microsatellites showed no differences for among loci within populations as compared with among populations within loci. For protein loci, however, the former was higher, indicating selection affecting allele frequencies at some loci. The variance among protein loci was significantly higher than among microsatellite loci, further indicating selection at some protein loci. There was significant differentiation among populations for both protein and microsatellite loci, most likely reflecting the geography of south-east Asia, and the presumed spread of goats throughout the region. Phylogenies derived from pair-wise genetic distance estimates show some similar clustering for the microsatellite and protein based trees, but bootstrap support was generally low for both. A phylogeny based on the combined set of 38 protein and microsatellite loci showed better consistency with geography and higher bootstrap values. The genetic distance phylogeny and the Weitzman diversity tree derived from microsatellite data showed some identical clusters, and both identified the Ujung Pandang and Australia populations as contributing most to overall genetic diversity.  相似文献   
75.
Covalent organic frameworks (COFs), in which molecular building blocks form robust microporous networks, are usually synthesized as insoluble and unprocessable powders. We have grown two-dimensional (2D) COF films on single-layer graphene (SLG) under operationally simple solvothermal conditions. The layered films stack normal to the SLG surface and show improved crystallinity compared with COF powders. We used SLG surfaces supported on copper, silicon carbide, and transparent fused silica (SiO(2)) substrates, enabling optical spectroscopy of COFs in transmission mode. Three chemically distinct COF films grown on SLG exhibit similar vertical alignment and long-range order, and two of these are of interest for organic electronic devices for which thin-film formation is a prerequisite for characterizing their optoelectronic properties.  相似文献   
76.
INDEPTH geophysical and geological observations imply that a partially molten midcrustal layer exists beneath southern Tibet. This partially molten layer has been produced by crustal thickening and behaves as a fluid on the time scale of Himalayan deformation. It is confined on the south by the structurally imbricated Indian crust underlying the Tethyan and High Himalaya and is underlain, apparently, by a stiff Indian mantle lid. The results suggest that during Neogene time the underthrusting Indian crust has acted as a plunger, displacing the molten middle crust to the north while at the same time contributing to this layer by melting and ductile flow. Viewed broadly, the Neogene evolution of the Himalaya is essentially a record of the southward extrusion of the partially molten middle crust underlying southern Tibet.  相似文献   
77.
The paper reports the observations of the aerosol studies carried-out for three years (2004-2007) during the summers and winters at Kaikhali (22.0220 N & 88.6140E) lying in the east coast of India inside a special mangrove ecosystem: 'The Sundarbans'. Aerosol optical depths were measured using a five filter channel sunphotometer with wavelengths at 340, 500,870, 936 and 1020 nm respectively. The sampling site enjoys a tropical climate and is under the strong influence of the southwest or summer monsoon and weak northeast or winter monsoon. The mean aerosol optical depth (AOD) during the winters (2004-2007) for the filter channels 340, 500, 870, 936 and 1020 nm have been found to be 1.478, 1.014, 0.579, 0.541 and 0.523 respectively whereas for the summer periods, they have been found to be 1.173, 0.859, 0.603, 0.564 and 0.597 respectively. The mean values of the angstrom exponent calculated for the winter and summer months over the years 2004-2007 have been found to be 1.283, 0.999, 1.285 and 1.094, 1.167 and 1.91 respectively. Generally the higher angstrom exponent values during the winter periods over the years from 2004-2007 except for the year 2005-2006 indicate high ratio of smaller fractions to larger fractions. The values of Angstrom exponents observed at the site suggest that the aerosol comprise mostly of the small size particles. An attempt has been made in the paper to compare the aerosol optical depth and angstrom exponent values with another study conducted in a different coastal zone in India.  相似文献   
78.
79.
Bacillus subtilis, a Gram‐positive, aerobic, endospore‐forming bacterium, was evaluated for its probiotic potential in Indian major carp, Labeo rohita. Labeo rohita (15±2 g) were fed a feed containing B. subtilis in three concentrations for 2 weeks, e.g., 0.5 (T2), 1.0 (T3) and 1.5 (T4) × 107 CFU g?1 feed. The control group (T1) was fed feed without B. subtilis for the same period. Haematological and serum parameters were monitored at weekly intervals. The response variables were total erythrocyte count, total leucocyte count (TLC), haemoglobin, total protein, albumin, globulin, albumin–globulin ratio, alkaline phosphatase activity, alanine aminotransferase activity and aspartate aminotransferase activity. Fish were challenged intraperitoneally with a virulent strain of Aeromonas hydrophila after 2 weeks of feeding to the treatment groups and positive control group, while the negative control group was challenged with phosphate‐buffered saline only. Clinical signs and symptoms, and mortality/survival percentage were noted in each group. The haematological and serum parameters were monitored each week and during post challenge on the third and tenth day. The B. subtilis‐treated fish (T4, 1.5 × 107 CFU g?1 feed) showed maximum per cent survival (87.50%), weight gain (35.5%), TLCs (3.23 × 104 cells mm?3), haemoglobin content (7.4 g%), total protein (2.37 gdL?1) and globulin content (1.28 g dL?1) during the pre‐challenge. Enzymes showed higher activities during post challenge (P<0.05). The result suggests that B. subtilis can be used effectively as a commercial product for use in aquaculture.  相似文献   
80.
Twelve experimental diets (D‐1 to D‐12) in a 4 × 3 factorial design (four protein levels: 250, 350, 400 and 450 g kg?1 and three lipid levels: 50, 100 and 150 g kg?1) were formulated. Carbohydrate level was constant at 250 g kg?1. Rohu fingerlings (average wt. 4.3 ± 0.02 g) were fed the experimental diets for 60 days in three replicates at 2% BW  day?1. Weight gain (%), specific growth rate (% day?1) and feed gain ratio (FGR) indicated that diets containing 450 g kg?1 protein and 100 or 150 g kg?1 lipid (diets D‐11 and D‐12) resulted in best performance, although results were not significantly different from those of diet D‐9 (400 g kg?1 protein and 150 g kg?1 lipid). Protein efficiency ratio was highest with diets D‐6 (350 g kg?1 protein and 150 g kg?1 lipid) and D‐9 (400 g kg?1 protein and 150 g kg?1 lipid) (P > 0.05) and declined with higher and lower protein diets at all levels of lipid tested. Elevated lipid level (50, 100 or 150 g kg?1) did not produce better FGR in diets containing 400 and 450 g kg?1 dietary protein (P > 0.05). The combined effects of protein and lipid were evident up to 400 g kg?1 protein. Growth and FGR showed consistent improvement with increased lipid levels from 50 to 150 g kg?1 at each protein level tested except with diets containing 450 g kg?1 protein. Apparent nutrient digestibility (for protein, lipid and energy) did not show significant variation among different dietary groups (P > 0.05). Whole body protein and lipid contents increased significantly (P > 0.05) with dietary protein level. The results of this study indicate that rohu fingerlings are adapted to utilize high protein in diets with varying efficiency. The fish could utilize lipid to spare protein but there is no significant advantage from this beyond the dietary protein level of 350–400 g kg?1 in terms of growth and body composition.  相似文献   
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