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131.
Currently, white lupin (Lupinus albus L.) is gaining importance due to its high nitrogen fixation capability and potential in sustainable crop production systems. Even though research conducted in Australia, Chile, Germany, New Zealand, and Portugal has indicated lupin's positive potential as human and animal food, such information from Virginia and adjoining areas of the United States is not available. In addition, effects of growing environment and genotypes on lupin seed composition need to be characterized to evaluate lupin's potential as a food and feed crop. Towards this end, seed of 12 lupin genotypes produced in Maine (USA) and Virginia (USA) were compared to determine genotypic and environmental effects on contents of protein, sugar, oil, various fatty acids, amino acids, and minerals. The protein content of dry seed was not affected by growing environment. However, growing environment had significant effects on contents of total sugar, amino acids, oil, fatty acids, and minerals. Significant variation existed among 12 lupin genotypes for various traits when composition of seed produced in Virginia was evaluated. The results indicated that site-specific evaluation of adapted lupin genotypes for chemical composition should be included in efforts to evaluate lupin's overall potential as a food or feed crop.  相似文献   
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133.
通过对天山南北坡25个样地的物种-面积关系的研究,结果发现:①所有样地种-面积关系斜率的平均值为0.21±0.02,低于全球平均水平;②草甸、草原和荒漠的种-面积关系的斜率分别为0.14±0.02,0.13±0.01和0.28±0.02.草甸和草原的种-面积关系斜率无显著差别,但两者显著低于荒漠的种-面积关系斜率;③天...  相似文献   
134.
新疆山地针叶林植物物种组成与丰富度研究   总被引:1,自引:0,他引:1  
通过对新疆阿尔泰山、天山北坡、天山南坡和昆仑山西部11个地点122个样方的调查,发现阿尔泰山针叶林植物(包括乔木、灌木和草本)丰富度显著高于天山南坡和昆仑山;天山南坡和昆仑山物种组成相似,阿尔泰山和天山北坡物种组成相似.全疆针叶林物种丰富度随年平均气温和海拔的增加显著下降,随纬度的升高显著升高.在不同区域,物种丰富度随...  相似文献   
135.
The Miniature Thermal Emission Spectrometer (Mini-TES) on Opportunity investigated the mineral abundances and compositions of outcrops, rocks, and soils at Meridiani Planum. Coarse crystalline hematite and olivine-rich basaltic sands were observed as predicted from orbital TES spectroscopy. Outcrops of aqueous origin are composed of 15 to 35% by volume magnesium and calcium sulfates [a high-silica component modeled as a combination of glass, feldspar, and sheet silicates (approximately 20 to 30%)], and hematite; only minor jarosite is identified in Mini-TES spectra. Mini-TES spectra show only a hematite signature in the millimeter-sized spherules. Basaltic materials have more plagioclase than pyroxene, contain olivine, and are similar in inferred mineral composition to basalt mapped from orbit. Bounce rock is dominated by clinopyroxene and is close in inferred mineral composition to the basaltic martian meteorites. Bright wind streak material matches global dust. Waterlain rocks covered by unaltered basaltic sands suggest a change from an aqueous environment to one dominated by physical weathering.  相似文献   
136.

Effects of zinc oxide nanoparticles (ZnO NPs) and Rhizobium leguminosarum alone and in combination were observed on the disease complex of pea caused by Meloidogyne incognita and Pseudomonas syringae pv. pisi. Plants inoculated with M. incognita and P. syringae pv. pisi, alone or in combination, showed a significant reduction in plant growth, chlorophyll and carotenoid content compared to uninoculated controls. Use of ZnO NPs (0.10?ml?1) as seed priming resulted in a greater increase in plant growth than 0.10?ml?1 foliar spray. Plants inoculated with R. leguminosarum had better plant growth, chlorophyll and carotenoid content than plants without R. leguminosarum. Greater plant growth, chlorophyll and carotenoid content were observed when NPs primed seeds were grown with R. leguminosarum than the use of NPs foliar spray plus R. leguminosarum. Plants inoculated with R. leguminosarum showed higher root nodulation while only few nodules were observed in plants without R. leguminosarum. Both tested pathogens had adverse effect on nodulation, while use of ZnO NPs with R. leguminosarum also reduced nodulation. ZnO NPs and R. leguminosarum reduced blight disease indices, galling and nematode population. Use of ZnO NPs primed seeds with R. leguminosarum resulted in the highest reduction in disease indices, galling and nematode population. The segregation of various treatments in the biplot of principal component analysis demonstrates a suppressive role of ZnO NPs on blight disease complex of pea.

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137.
Gram-negative marine bacteria can thrive in harsh oceanic conditions, partly because of the structural diversity of the cell wall and its components, particularly lipopolysaccharide (LPS). LPS is composed of three main parts, an O-antigen, lipid A, and a core region, all of which display immense structural variations among different bacterial species. These components not only provide cell integrity but also elicit an immune response in the host, which ranges from other marine organisms to humans. Toll-like receptor 4 and its homologs are the dedicated receptors that detect LPS and trigger the immune system to respond, often causing a wide variety of inflammatory diseases and even death. This review describes the structural organization of selected LPSes and their association with economically important diseases in marine organisms. In addition, the potential therapeutic use of LPS as an immune adjuvant in different diseases is highlighted.  相似文献   
138.
Wood Science and Technology - Bulking treatment with low molecular weight phenol formaldehyde (LmwPF) resin has been found to successfully enhance the properties of low-density wood but emit higher...  相似文献   
139.
A large proportion of global natural rubber production takes place in Southeast Asia. The majority of this rubber is produced by smallholders. Thailand, Indonesia and Malaysia are the three principal countries involved. In Malaysia and Indonesia the smallholder sector accounts for 72% and 84% of total rubber production respectively. In other countries rubber plays a significant role on a more local basis. Imperata is a serious problem for the smallholder rubber farmer in most of Southeast Asia in three respects: the high cost (labour and/or capital) of opening Imperata-infested land, its competitive effect on rubber and annual intercrops, and the fire hazard that it poses during the dry season as a major source of combustible material. The costs of Imperata to smallholders are substantial in terms of a direct loss through fire and revenue foregone or delayed as a result of competition. Most smallholders intercrop their rubber during the first 1–3 years after planting it, and during this period Imperata is reasonably well controlled. Intercropping is only feasible for a limited period because of limited soil fertility and/or the shading effect of the rubber trees. After intercropping, Imperata tends to establish itself for a few years until it too is shaded out by the rubber. This is the problem period, during which farmers practise only limited weed management, if any.A large amount of research has been done on methods of controlling Imperata, but the recommended methods have been generally spurned by smallholders unless they have been given subsidies to apply them. This paper describes the precise nature of the Imperata problem, with reference to some of the smallholder rubber-based farming systems within Southeast Asia; the different Imperata control strategies currently practised in these farming systems; and some of the constraints on the adoption of currently and recently recommended practices. It then proposes a ten-point agenda for research on Imperata control, including two ways in which current research programmes could be usefully reoriented: first, they need to take greater account of smallholder farming systems and constraints; and second they should shift their emphasis from single-method to integrated control systems.  相似文献   
140.
With the goal of preparing low-cost functional food, squid protein hydrolysate (SPH) was extracted from four squid species by protease treatment. Peptides are the major components (approximately 84-88%) of the SPH. The stabilization effects of 5% SPH (dried weight/wet weight) on the state of water and the denaturation of frozen lizard fish Saurida wanieso myofibrillar protein (Mf) were evaluated on the basis of desorption isotherm curves with respect to Ca2+-ATPase inactivation and the presence of unfrozen water, which was determined using differential scanning calorimetry during dehydration, and the effects were compared with those of sodium glutamate. The Mf with SPH was found to contain higher levels of monolayer and multilayer sorption water, resulting in decreased water activity and Ca2+-ATPase inactivation. The amount of unfrozen water in Mf with SPH increased significantly, suggesting that the peptides of SPH stabilized water molecules on the hydration sphere of Mf, which maintained the structural stability of Mf, and therefore suppressed dehydration-induced denaturation. The effect by SPH was less than that by sodium glutamate.  相似文献   
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