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131.
To dye poly(lactic acid) (PLA) fiber with natural dyes has gained importance in recent years due to the production of the fully eco-friendly textile products. In this study, pure and modified PLA fibers with two different POSS nanoparticles, namely N-phenyl aminopropyl POSS (AP-POSS) and octa (aminophenyl) polyhedral oligomeric silsesquioxane (OAPPOSS), are dyed with three different natural dyes including alizarin, lawsone and indigo. The effects of the dyeing conditions including dyeing temperature and time, POSS nanoparticle concentration, natural dye types and concentrations are investigated on the dyeability properties of the PLA fiber samples. The wash and light fastness of the fiber samples are also investigated. According to the dyeability results, it is concluded that POSS nanoparticles are effective for increasing the dyeability of the PLA fiber with all natural dyes used in this study. As the added amount of the POSS nanoparticle increases, the dyeability of the PLA fiber increases. When the performances of the POSS nanoparticles are compared, it is seen that OAP-POSS is more effective than the AP-POSS nanoparticle.  相似文献   
132.
Effects of the chitin synthesis inhibitor diflubenzuron (DFB) on the integument of 5th instarGalleria mellonella L. larvae were investigated. When larvae were fed with semi-artificial diets containing 250, 500 and 1000 ppm of the compound, DFB affected the integument. The affected larvae failed to ecdysis, their cuticle was ruptured, lost haemolymph and blackened. In treated larvae, cuticle deposition was disrupted and the cuticle thickness was decreased by ∼50% compared with the untreated control, particularly at day 3 1/2. However, statistically there was no significant difference among the three concentrations (P>0.05). This may indicate that all three concentrations are equally effective in decreasing level. DFB at 500 and 1000 ppm also affected the epidermal cells and caused the occurrence of vacuoles. http://www.phytoparasitica.org posting Dec. 16, 2003.  相似文献   
133.
The aim of the present study was to evaluate the effect of different doses dexamethasone and progestagen-PMSG on fertility and prolificacy in Kivircik ewes during the breeding season. For the experiment, 100 ewes were divided into four groups, with 25 females in each group. Groups were fluorgestone acetate (FGA, 30 mg), administered via intravaginal sponges. Experimental groups 2, 3 and 4 mL dexamethasone injection were given 72 h before mating season. The fertility rates control, 2, 3 and 4 mL were 88.0, 92.0, 100.0 and 100.0%, respectively (p<0.05). The prolificacy rates for the same groups were 122.7, 130.4, 144.0 and 156.0%, respectively (p<0.01). The injections dexamethasone significantly increased lamb birth weight and daily weight gain for 60 days (p<0.05).  相似文献   
134.
In this study, some of the empirical methods such as USDA-SCS and volume balance equations were used for determining furrow length. The main purpose was proving empirical equations application possibility. According to results, USDA-SCS and Volume Balance Equations can be used for determining furrow length at the Bafra Plain, Turkey. The field experiment and Volume Balance results are very close to each other. Experimental results are different from USDA-SCS equation results, but there is a relationship between both. There is a coefficient between field results and USDA-SCS equation result for furrow length. The coefficient (0.41) can multiply by UDSA-SCS result is 73 m which is very close to the field experimental result of 71 m.  相似文献   
135.
Conductive polyaniline (PAn)/poly(ethylene terephthalate) (PET) composite fibers were prepared by chemical polymerization of aniline in the presence of PET fibers using benzoyl peroxide (Bz2O2) in organic solvent/aqueous hydrochloric acid mixtures. The effects of polymerization conditions such as organic solvent/water ratio, oxidant, aniline and hydrochloric acid concentrations and temperature were investigated on the amount of PAn deposited on PET fiber and the electrical surface resistance of composite fibers. The maximum PAn content and the lowest electrical surface resistance of composite fibers were observed at HCl concentrations of 0.5 mol L−1. The properties of PAn/PET composite fibers such as density, diameter, tensile strength and breaking elongation were also investigated in comparison with those of pure PET. Characterization of conductive composite fibers was carried out by FTIR, TGA, SEM techniques, surface resistance measurements, and cross section images taken by optical microscope.  相似文献   
136.
The primary purpose of water aeration is to increase the oxygen saturation of the water. This can be achieved by using hydraulic structures because of substantial air bubble entrainment at these structures. This paper reviewed the literature on hydraulic structures used in water aeration processes. The hydraulic structures were divided into two groups as the high-head flow systems and the free-surface flow systems. The high-head flow systems were circular and venturi nozzles, pipe with venturi tube, and high-head conduit, and the free-surface flow systems were weir, stepped cascade, and free-surface conduit. Air/water flow ratio and aeration efficiency in circular nozzles with air holes and venturi nozzles were significantly high. Pipes with venturi tubes showed high aeration efficiency although they had low air/water flow ratio. In high-head and free-surface conduits, almost full oxygen transfer, up to the saturation value, occurred. Forty-five degrees triangular sharp-crested weir had significantly better air/water flow ratio and aeration efficiency than other sharp-crested weir shapes. Stepped cascades, in particular nappe flow regime, were very efficient means of aeration.  相似文献   
137.
138.
The synthesis of 2-endo,3-exo,5-endo,6-exo,8,9,10-heptachlorobornane (B7-1001, Hp-Sed) and 2-endo,3-exo,5-endo,6-exo,8,9,9,10-octachlorobornane (B8-1412) is described. Both compounds are components of toxaphene, an insecticide that has been widely used in the past. B7-1001 is an important toxaphene congener, comprising up to 99% of total toxaphene concentrations found in fish and sediment samples from treated lakes. B8-1412 is also a significant component of toxaphene contamination in samples from biota. In synthesizing the compounds, 2-exo,3-endo,6-endo,8,9,10-hexachlorobornane (B6-913) was obtained by reduction of the well-known toxaphene component P 32 (B7-515, 2,2,5-endo,6-exo,8,9,10-heptachlorobornane), which was itself isolated from the chlorination products of (+)-camphene. Chlorination of B6-913 provided B7-1001 in 49.5% yield, and P 32 and four other heptachlorobornanes were also detected in the reaction mixture. Structures of two of the heptachlorobornanes were elucidated by MS and NMR as 2-exo,3-endo,6-endo,8,9,9,10-heptachlorobornane (B7-1461) and 2-exo,3,3,6-endo,8,9,10-heptachlorobornane (B7-1303). B8-1412 was isolated from the product mixture obtained by chlorination of 2-exo,3-endo,6-endo,8,9,9,10-heptachlorobornane. Photolysis experiments at lambda = 254 nm revealed that B6-913 is photochemicaly the most stable compound of the seven toxaphene compounds studied, with a t(1/2) of 213 h. B7-1001, having a t(1/2) of 82 h, was the second most stable compound. B8-1412 was degraded more rapidly, with a t(1/2) of 28.8 h, than B7-1001, but was still much more stable than P 50 (B9-1679, 2-endo,3-exo,5-endo,6-exo,8,8,9,10,10-nonachlorobornane), which had a t(1/2) of 9.4 h, despite its reputation as a very persistant compound. Under the same experimental conditions hexachlorobenzene (HLB) and octachlorodibenzodioxine (OCDD) were consumed very quickly with t(1/2) = 0.0025 and 0.0015 h, respectively.  相似文献   
139.
The essential oil from the gum of Pistachio (Pistacia vera L. (Anacardiaceae)) grown in Turkey was obtained by the hydro-distillation method, and its chemical composition was analyzed by GC and GC-MS. Moreover, the antimicrobial activities of the oil against the growth of 13 bacteria and 3 pathogenic yeasts were evaluated using the agar-disk diffusion and minimum inhibitory concentration (MIC) methods. The results showed that the essential oil contained about 89.67% monoterpenes, 8.1% oxygenated monoterpenes and 1.2% diterpenes. alpha-Pinene (75.6%), beta-pinene (9.5%), trans-verbenol (3.0%), camphene (1.4%), trans-pinocarveol (about 1.20%), and limonene (1.0%) were the major components. The antimicrobial results showed that the oil inhibited nine bacteria and all the yeasts studied, and the activities were considerably dependent upon concentration and its bioactive compounds such as carvacrol, camphene, and limonene. Moreover, the essential oil of the gum was found to be more effective yeastcide than Nystatin, synthetic yeastcide. Furthermore, the antibacterial activities of the oil were lower than those of standard antibiotics, ampicillin sodium, and streptomycine sulfate under the conditions studied.  相似文献   
140.
Soil compaction occurs due to heavy wheeling or repetitive tillage in the field. Soil compaction changes the soil physical parameters and water infiltration that cause reduction in the crop yield. Proper subsoiling alleviates the negative effect of soil compaction. The objectives of the research was to examine the effects of subsoiling on the resistance of the soil and to find out deep tillage effects on the cotton yield and the convenient time for applying subsoil treatment for reducing the soil compaction. One-pass (B) and two-passes (C) subsoil treatments were applied in the fields where wheat, silage maize (Zea mays L.) and cotton (Gossypium hirsutum L.) crops were grown by 2 years rotation. The experiment was started in 1998 and carried out for 4 years. Soil penetrations were measured during the experiments years at thaw conditions of silty-clay soil (43% clay, 50% silt, 7% sand) before seedbed preparation in autumn seasons. According to the results, the subsoiling treatments created statistically significant effects on the soil resistance (P<0.05) comparing the control plots (A). The initial disruption in subsoiled plots has almost disappeared after 2 and 4 years in B and C plots, respectively. The soil resistance in C plots was lower than in B plot. The percentage of decrease in the soil resistance from A to B and A to C plots was calculated as 13.3 and 26.2%, respectively, in the first year. In the effective subsoiling area from 0.20 to 0.50 m depth, the ratio of penetration decrease in both plots was about 7–8% per year. The difference of penetration decrease between B and C plots was found to be about 15.8% level. Cotton yields at each subsoiled plots increased slightly comparing with control plots (A) where subsoiling was not applied. However, these increments were found to be statistically insignificant. It may be concluded that the subsoiling treatments does not affect the crop yield in intensive and fully irrigated field conditions.  相似文献   
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