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基于SECI知识转化模型的农民技能培养模式研究 总被引:3,自引:0,他引:3
通过对农民能力形成的动态性和能力形成的主要方式分析,并根据SECI知识转化模型和动态能力理论,指出当前新农村建设过程中加强农民技能培训,提高广大农民的能力对促进农业产业结构的调整和农村经济发展的重要性。 相似文献
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怎样快速准确的确定液压阀在液压系统中的故障现象,一直是液压工作者有待解决的问题。该实验台通过某些特殊设计的插装装置和快换管接头,把假设有故障的液压元件和实验台快速连接起来,可进行各种性能检测,确定其损坏程度,从而节省了诊断故障的时间并避免了维修中不必要的损伤。在教学上,该实验台可使实验者自选液压元件,设计、组装液压基本回路或液压系统,从而打破了以往实验者“只能看不能动”的蔽病,提高实验者的动手能力。在工程上,利用该实验台模拟制造的液压系统,可预测其实际工作状况的好坏,从而避免了在实际生产制造中由于某些性能指标达不到要求而带来的不良后果。 相似文献
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党参茎基腐病镰孢菌鉴定及其对杀菌剂的敏感性研究 总被引:1,自引:0,他引:1
为明确党参茎基腐病害的病原、致病性和优势病原种类及其对不同杀菌剂的敏感性,采用组织分离法进行病原菌分离,并根据其培养性状、形态学和分子生物学特征进行鉴定,同时采用平皿菌丝生长抑制法测定不同药剂的敏感性。结果表明,该病害的病原为尖孢镰孢菌(Fusarium oxysporum)、茄病镰孢菌(F. sonali)和木贼镰孢菌(F. equiseti),其中尖孢镰孢菌为优势种。室内致病性测试结果表明,3种镰孢菌均可引起党参茎基腐病,其中尖孢镰孢菌的致病性最强,显著高于其他2种菌。供试药剂对菌丝生长均有抑制作用,苯醚甲环唑对3种镰孢菌具有很强的抑制活性,同时3种镰孢菌对吡唑醚菌酯的敏感性较高。 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(16):1925-1943
Abstract Changes in soil chemical properties were investigated in conjunction with an ongoing study of fertility and irrigation relationships of cotton. Four irrigation methods and five nitrogen fertilization rates were the primary focus of the study. The four irrigation regimes studied were: high frequency center pivot, low frequency center pivot, furrow irrigated, and unirrigated. Nitrogen rates were 0, 30, 60, 90, and 120 lb N/A. Soil samples were collected from each plot in 6‐in‐ increments to a depth of 24 in. in 1982 and again in 1986 after four years of continuous cotton production. The soil samples were analyzed for pH, organic matter (OM), P, K, electrical conductivity (EC), and NO3 ‐‐N. All background soil characteristics were found to vary with depth with the exception of NO3 ‐‐N. The follow‐up sampling and testing in 1986 showed significant differences in soil properties as a function of irrigation, N‐fertilization, depth, and their interactions. Nitrates were accumulated in the 18 to 24‐in. depth under high (120 lb N/A) fertilization, and in the 0 to 6‐in. depth under the four lower treatments (0, 30, 60, and 90 lb N/A). Soil pH was highest in the furrow and high frequency center pivot irrigated regimes and lowest in the unirrigated regime. Soil pH also decreased with depth. Electrical conductivity of the soil was highest in the high frequency regime and not significantly different among the other three irrigation methods. The 0M content of the soil was greatest in the high frequency regime but not significantly different in the low frequency, furrow, or unirrigated blocks. Soil 0M was found to decrease with depth through 18 in. in all cases. The P and K status of the soil was not changed as a result of the N fertilization or irrigation treatments. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(6):903-909
Abstract The effect of grinding force, time, and weight of soil on the NH4HCO3 ‐DTPA extractable levels of Fe, Zn, Mn, Cu, P and K from 10 Colorado soils were studied. It was found that the amount of extractable iron and zinc increased, with an increase in force or time of grinding. The significant interaction between time and force of grinding indicates that the combined effect of the larger force and the longer time in increasing the extractable levels of Fe and Zn was greater than the additive effects of these factors. The weight of soil being ground had a small effect on extractable Fe (significant at 10% level) and no effect on other elements. Extractable levels of Mn, Cu, P, and K were not affected by the grinding treatments. Iron was increased 112% and zinc was increased 44% due to the combined effects of the larger force and the longer time of grinding in soils averaging 12.8 and 1.1 ppm in Fe and Zn, respectively. It is concluded that grinding variables should be standardized, otherwise interlaboratory comparisons and standardized interpretations of results are not possible. 相似文献