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91.
Among the commonly consumed food legumes, lentils occupy an important place in human nutrition in the Indian subcontinent. Twenty-one lentil genotypes were evaluated for such nutrition related parameters as moisture, protein, crude fiber, fat, ash (total mineral matter), carbohydrates, total energy and metabolizable energy. These genotypes were also analyzed for 100-seed weight and seed yield/plant. Protein content ranged between 22.1 and 27.4% with significant differences among genotypes. Considerable variations were observed among the genotypes for calcium, phosphorus, iron and tannin contents. Large variations existed in yield and 100-seed weight of these genotypes. Seed yield/plant was not significantly correlated with any of the principal seed constituents analyzed in the present study. The genotypes, LH 97 and LH 37 were found to be better and hence could be explored for further development and selection of desirable characteristics.  相似文献   
92.
以云母、硫磺、石膏、草炭、褐煤为辅加材料,试验对水稻吸氮和生长的影响,硫磺和石膏效果较好,特别是石膏,吸氮量达到3068.36mg/盆,比追肥增加10.6%;与追肥相比较,硫磺和石膏氮肥利用率分别提高2.2%和9.8%,产量提高2.6%和13.5%,并且改善品质。  相似文献   
93.
The effect of chromium (chromium picolinate, CrPic) supplementation at various levels (0, 400, 800 or 1600 μg Cr/kg diet) on serum concentrations of glucose and cholesterol and on serum and liver concentrations of Cr, Zn, Cu and Fe of rainbow trout (Oncorhynchus mykiss) was evaluated. One-year-old rainbow trout (n=120) were randomly assigned to four treatment groups, each with two replicates of 15 fish. The fish were fed either a control diet or the control diet supplemented with either 400, 800 or 1600 μg Cr/kg diet. Serum glucose and cholesterol concentrations decreased (p=0.001) with higher dietary chromium supplementation. Increasing dietary chromium supplementation linearly increased serum chromium and zinc concentrations (p=0.001). Serum copper and iron concentrations did not change (p>0.10) as dietary chromium supplementation increased. Liver chromium and zinc concentrations linearly increased (p=0.001). Also, liver Cu and Fe concentrations did not change (p>0.10) as dietary chromium supplementation increased. The results of present study conclude that supplemental chromium to the diet of rainbow trout influences serum and liver Cr and Zn concentrations, thus most probably functions of the organs as well as the welfare of raibow trout.  相似文献   
94.
细菌在两种土壤矿物表面吸附的热力学分析   总被引:1,自引:0,他引:1  
运用表面热力学方法和扩展的DLVO理论,对两种典型土壤细菌恶臭假单胞菌(Pseudom onasputida)和枯草芽孢杆菌(Bacillus subtilis)在代表性土壤黏粒矿物高岭石和蒙脱石表面的吸附进行了分析,获得了黏粒矿物与细菌作用的疏水自由能变(ΔGH)和静电力自由能变(ΔGEL)及总自由能变(ΔG)。发现疏水自由能为负,显示疏水作用为引力,有利于细菌在黏粒矿物表面的吸附;而静电力自由能为正,表明细菌-矿物间存在静电斥力。疏水自由能显著大于静电力自由能,表明疏水作用在黏粒矿物对细菌吸附时的贡献大于静电力。两种细菌与两种矿物间的总吸附自由能为负值,意味着细菌在矿物表面的吸附是热力学自发过程。高岭石对细菌的吸附自由能大于蒙脱石对细菌的吸附自由能,表明细菌与高岭石间的亲和力较高,吸附更容易发生,这与化学吸附及滴定量热结果一致。表面热力学方法和XDLVO理论在预测细菌-矿物相互作用中有重要意义,但该方法未考虑多种非DLVO效应,如细胞表面多聚物、细菌鞭毛等在吸附反应中的作用,因此还存在一定的局限性,在揭示细菌-矿物相互作用的热力学机理方面还需与其他研究技术结合。  相似文献   
95.
The role of high carbon dioxide (CO2) levels on fish performance, bone structure/composition and as a potential cause of spinal deformities was studied. Two groups of fish were exposed to a low (control) and a high level of CO2 for 135 days during the freshwater period. After smoltification, the fish were transferred to seawater and followed up for 517 days until they reached harvest weight (3.1 kg BW).Differences in body weight between the control and high CO2 groups were observed. At the end of the freshwater period, average weight in the group exposed to high CO2 levels was 20.9% lower than in the control group. Specific growth rates (SGR) from the start of the experiment (10 g BW) to smolt stage were 1.63 ± 0.04 and 1.36 ± 0.01 for the control group and the high CO2 group, respectively. Differences in body weight were maintained during the initial stages of the seawater period, but were not observed at harvest weight.Nephrocalcinosis was not observed in any of the experimental groups at the end of the freshwater period and no external signs of spinal deformities were observed either at smolt stage or at harvest weight. X-rays revealed mild abnormalities in some vertebrae bodies, which could not be related to any experimental group. Despite the lack of signs of pathological bone alterations, the histological examination suggested that the exposure to high CO2levels resulted in an increase in trabeculae volume and a higher rate of bone remodeling at the end of the freshwater period. Furthermore, fish exposed to a high CO2 level presented a higher bone ash content at the end of the freshwater period. These differences could not be observed at the end of the grow-out period.  相似文献   
96.
Abstract

Three tobacco varieties were grown for three consecutive years on plots that were fertilized to produce a 2X2 factorial of soil acidity and soil fertility. Leaf samples and height measurements were taken periodically each year. The plant samples were analyzed for eleven elements. Rainfall differences among years provided information concerning the seasonal moisture effects on the treatment variables. Data presented show that the stage of growth, the soil fertility and acidity and the relative moisture stress affect tobacco height and the mineral composition of tobacco leaves. The information can be useful in assigning magnitude and direction for plant age and climatic interactions in practical diagnostic work.  相似文献   
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