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91.
成玉梅 《河南科技大学学报(农学版)》2001,21(2):115-116
烘干、磨碎、过40目筛的牡丹叶样品,用水浸提法、醋酸铵浸提法及硫酸消化法制备待测液,火焰光度法测定牡丹叶钾的百分含量分别为0.978,9.0825,0.9788,显著性检验结果表明三者相关不显著,说明在测定牡丹叶含量时,可以用水浸提法制备待测液。 相似文献
92.
Methane fluxes were measured monthly over a year from tropical peatland of Sarawak, Malaysia using a closed-chamber technique. The CH4 fluxes in forest ecosystem ranged from −4.53 to 8.40 μg C m−2 h−1, in the oil palm ecosystem from −32.78 to 4.17 μg C m−2 h−1 and in the sago ecosystem from −7.44 to 102.06 μg C m−2 h−1. A regression tree approach showed that CH4 fluxes in each ecosystem were related to different underlying environmental factors. They were relative humidity for forest and water table for both sago and oil palm ecosystems. On an annual basis, both forest and sago were CH4 source with an emission of 18.34 mg C m−2 yr−1 for forest and 180 mg C m−2 yr−1 for sago. Only oil palm ecosystem was a CH4 sink with an uptake rate of −15.14 mg C m−2 yr−1. These results suggest that different dominant underlying environmental factors among the studied ecosystems affected the exchange of CH4 between tropical peatland and the atmosphere. 相似文献
93.
We developed a deterministic and stochastic age-based matrix projection population model to assess and quantify the impact of mortality caused by chronic oil pollution and legal hunting on thick-billed murre Uria lomvia populations breeding and wintering in eastern Canada. We calculate the potential population growth rate in the absence of anthropogenic mortality sources using a modeling technique that translates absolute number of birds killed from anthropogenic mortality to potential survival rates in the absence of these anthropogenic impacts. The intrinsic growth rate of the deterministic matrix based on vital rates from Coats Island (λd=1.0102), as well as the stochastic growth rate (λs=1.0098, 95% C.I. 0.9969-1.0226), matched observed population trends. Hunting mortality reduced population growth rate by 0.020 (0.012-0.039), oiling mortality reduced population growth rate by 0.025 (0.012-0.039). Combined these sources reduced the population growth rate by 0.047 (0.033-0.610). Although thick-billed murre populations are stable or slowly growing in eastern Canada, anthropogenic sources of mortality are reducing the ability of the population to grow, and increase vulnerability in these populations to changes in their environment and other pulse perturbations. Our modeling technique could be used to assess specific anthropogenic impacts on populations where a vital rates and numbers killed are known, but no long-term trend information is available. 相似文献
94.
牡丹的电镜观察及其干燥特性分析 总被引:7,自引:0,他引:7
针对植物组织在电镜样品制备过程中,表面的细微结构易产生皱缩、塌陷、变形等缺陷,对样品制备中固定、脱水、干燥等几种处理方法进行了对比研究,发现经过戊二醛、甲醛混合固定,无水乙醇连续脱水,微波辐射临界点干燥法处理后的样品微形态结构保持良好。在扫描电镜下,对牡丹的枝、叶、花瓣等样品的微形态结构进行了观察,并结合冷冻干燥的试验结果,分析了样品的微形态结构与其干燥特征的关系,为牡丹的干花制作等深加工工艺提供了试验依据。 相似文献
95.
Understanding the effects of oil contamination on the composition and function of soil microbiota entails investigation of the effects of a mixture of hydrocarbons at the community level in a complex environmental matrix. One approach to this difficult problem is to ally a community-level fingerprinting approach with bioassays that have a physiological or functional implication. Two contrasting refined oils (paraffin and motor oil) were used to contaminate soil microcosms, and a simulated bioremediation treatment with nutrient-addition was applied. The indigenous microorganisms were monitored over 103 d using complementary community-level techniques (carbon source physiological profiling using Biolog® microplates, and phospholipid fatty acid (PLFA) profiling). Changes in the toxicity of the applied oils were monitored using luminescent bacterial bioassays, including Vibrio fischeri and a hydrocarbon-degrading Pseudomonas putida strain. Distinct shifts in microbial community structure and C source utilization profiles were observed as a result of oil contamination. There was some evidence that bioremediated soils were returning to control values by the end of the experiment. This was supported by the bioassay results which showed an initial increase in toxicity as a result of the oil addition which had then decreased by the conclusion of the experiment. The two oils exhibited markedly different toxicity towards the bioassay organisms, with species-specific differences in response. This oil-specific difference was also found in the PLFA profiles which showed the two oil types selected different microbial communities. 相似文献
96.
97.
98.
介绍了感应电动机热负荷、温升与有效体积之间的关系,提出了充油式潜水电机节材的两条重要依据,即冷却条件好和减小有效体积就可减小油耗,并列举了实例。 相似文献
99.
鸡毒支原体油乳剂灭活苗对降低鸡毒支原体垂直传播作用的研究 总被引:2,自引:0,他引:2
本试验将30只MG阴性的20周龄的蛋种鸡随机分为4组,Ⅰ组于21和25周龄、Ⅱ组仍于25周龄时分别颈部皮下接种MG油乳剂灭活苗0.5ml/只,Ⅲ组于攻毒后1周接种1ml/只,另设一组对照,不接种疫苗。各组均在29周龄时用通过SPF鸡两次复壮的MG-BG44T株经左胸气囊和鼻腔攻毒。收集攻毒后1-7周内所产的蛋,用PCR方法检测鸡蛋卵黄膜中的MG。结果在攻毒后7周内各免疫组(Ⅰ、Ⅱ、Ⅲ)的垂直传播率显著低于对照组(P<0.01),分别比对照组低26.37%、12.8%、13.64%。攻毒后各免疫组和对照组经4次采样均可从喉头拭子中分离到MG但免疫组的分离率较低。攻毒后第7周从对照组鸡的气管、肺、气囊中均可分离到MG,而试验Ⅰ组仅在气管和肺中分离到了MG。试验Ⅰ组和对照组鸡的输卵管、心、肝、脾和肾中均未分离到MG。 相似文献
100.
文中综述了RAPD、SSR、ISSR、AFLP和SRAP等分子标记的原理和特点,及其在种质资源分类鉴定、亲缘关系分析、杂种鉴定等方面应用的现状,探讨了分子标记技术在牡丹亲缘关系分析、品种分类鉴定、遗传图谱构建和分子标记辅助育种等方面的发展前景。 相似文献