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111.
112.
对绿茶酒生产工艺进行了研究,确定了绿茶酒最佳工艺参数。采用热水浸提法提取,酒精发酵采用活性干酵母添加量6%,初始糖度为20%,发酵温度为28℃,酒精发酵时间为7d,体积分数为9.0%。成品酒呈亮黄色,具有茶和酒的香气,茶酒味适中。 相似文献
113.
Wang Zhun Zhang Hengheng Dong Qiang Gui Huiping Wang Xiangru Pang Nianchang Li Yongnian Niu Jing Jin Dingsha Wang Sujie Zhang Xiling Song Meizhen 《棉花学报》2021,32(6):538-551
[Objective] The aim of this study is to evaluate nitrogen efficient cotton germplasms and improve nitrogen use efficiency. [Method] Eighty cotton germplasms were selected and evaluated in the hydroponic experiment under low (0.25 mmol·L-1) and high (5 mmol·L-1) nitrogen concentration. Different traits for screening were identified and nitrogen use efficiency types were classified. Field experiments were also performed for comparison and confirmation of the identified germplasms. [Result] The results showed that there were significant differences in the total plant dry matter, shoot nitrogen accumulation and nitrogen absorption efficiency in cotton germplasms at the two nitrogen levels. Based on coefficient of variation, principal component analysis and correlation, six traits including total plant dry matter, shoot dry matter, root dry matter, total nitrogen accumulation, shoot nitrogen accumulation and nitrogen absorption efficiency were used as screening indicators. According to the Heatmap clustering analysis and the nitrogen efficiency comprehensive index, two germplasms (Lu05R59 and CCRI 69) were identified as low nitrogen tolerant and nitrogen efficient, and two germplasms (Coker 201 and Xinluzhong 30) as low nitrogen sensitive and nitrogen inefficient. The results of field experiment were consistent with the results of the hydroponic culture at the seedling stage. [Conclusion] It was finally determined that Lu05R59 and CCRI 69 were the low nitrogen tolerant and nitrogen efficient germplasms, and Coker 201 and Xinluzhong 30 were low nitrogen sensitive and nitrogen inefficient germplasms. The results of these studies provide the possibility for screening and rapid identification of nitrogen use efficiency in cotton at the seedling stage, and provide the ideal materials and theoretical basis for further study of cotton nitrogen efficient. 相似文献
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115.
枯草芽孢杆菌B26发酵液离心过微孔滤膜后,用质量分数为70%的硫酸铵沉淀,透析后获得仍具有拮抗多隔镰孢霉的无菌粗提物。进一步检测了粗提物对温度、酸碱度、紫外线照射、有机溶剂和蛋白酶处理的稳定性。结果表明,B26粗提物对高温具有一定的耐受性,经100℃处理后,是常温处理下抑菌直径的78.2%,但经121℃处理后,B26粗提物完全失去活性。B26粗提物具有较宽的pH值适应范围,在pH值3~10时都具有抑菌活性,且在pH值为7时的抑菌能力最高。粗提物对紫外线照射有部分敏感性,经距离40cm、功率20W的紫外灯照射80min后,抑菌活性是对照的78.1%。有机溶剂对B26抑菌粗提物的活性影响很小,经乙醚,甲醇,氯仿和丙酮处理30min后,粗提物抑菌活性分别为对照的96.4%,85.7%,82.1%,81.5%。B26抑菌粗提物对蛋白酶具有部分敏感性,蛋白酶K、胰蛋白酶和胃蛋白酶处理后的拮抗直径分别为15.2,16.2,16.3mm,抑制率分别是对照的76.7%,81.8%和83.3%。 相似文献
116.
选择12种我国不同产地的大米,通过相关性分析,研究方便米饭感官品质与大米主要化学成分及蒸煮性质之间的关系。结果表明,原料大米的主要化学成分与米饭的蒸煮性质对方便米饭感官品质有明显影响,特别是大米的直链淀粉含量与感官评定呈极显著负相关,硬度,胶稠度也都与感官评定有不同显著程度的相关性;直链淀粉含量低,胶稠度较低,含水量适中的大米生产的方便米饭有较好的感官品质。 相似文献
117.
通过MTT试验,评定大型毒菌发酵液提取物的直接细胞毒活性。结果表明:3个菌株发酵液提取物两种浓度组对PC-3细胞均有很好的抑制作用,与对照相比抑制效果差异显著(P〈0.05);不同药物、不同浓度组作用时间点均以120 h抑制率最高;不同浓度组作用120 h,以高浓度组抑制率最高。菌株CM4高浓度组给药120h对PC-3细胞的抑制活性最高,抑制率为90.23%;其次为CM4低浓度组,给药120h抑制率为86.37%。菌株CM4大型毒菌发酵液提取物对人前列腺癌细胞PC-3有明显的抗肿瘤作用。 相似文献
118.
冬枣绿盲蝽成虫毒力测定与防治方法研究 总被引:1,自引:0,他引:1
通过室内和田间试验,比较了14种不同农药对冬枣绿盲蝽成虫杀伤力的差异。筛选了4种对冬枣绿盲蝽成虫具有较好杀灭作用的农药。室内试验结果表明:在14种农药中,对冬枣绿盲蝽成虫具有较好杀灭效果的有敌敌畏、氰戊菊酯、甲氰菊酯和氟虫腈。其中氟虫腈效果最好,LC50为81.57μg/g,其次为敌敌畏和氰戊菊酯,LC50分别为232.58μg/g、291.28μg/g。而大田试验,各种农药的防治效果较差。采用叶片喷雾法,5%氟虫腈乳油1000倍与20%甲氰菊酯乳油800倍防治效果最好,分别为65.94%、64.24%。土壤处理,基本无法控制成虫危害。因此必须采取多种方法才能有效控制绿盲蝽的危害。 相似文献
119.
120.
Xiang Li Jian-zhi Niu Jiao Li Bao-yuan Xie Yi-ni Han Jing-ping Tan Ying-hu Zhang 《林业研究》2012,23(3):419-424
We studied the impact of forest vegetation on soil erosion,surface runoff, and sediment generation by using field simulated rainfall apparatus. We measured runoff and sediment generation of five 4.5 × 2.1m runoff plots (a bare soil as a control; two Pinus tabulaeformis forestplots and two Platycladus orientalis forest with row spacing of 1 m × 1m and 1.5 m × 1.5 m, respectively) in Beijing Jiu Feng National ForestPark under three rainfall intensities (0.42, 0.83, 1.26 mm per minute).Forest vegetation significantly reduced soil erosion and sediment yield.Mean total runoff volume in the four tree stand plots was 93% of that inthe control plot, demonstrating the limited effectiveness of forest vegetation in runoff control. With increasing rainfall intensity, runoff reductionin forest plots declined from 28.32% to 2.1%. Similar trends in runoff coefficient and the relationship between runoff volume and rainfall duration was observed. Mean total sediment yield and mean sediment yield reduction rate under different treatments was 55.05% and 43.17% of those in the bare soil control plot, respectively. Rainfall intensity playedan important role in runoff and sediment generation processes, and had agreater impact on runoff than on soil erosion and sediment generation.When considering several factors in runoff and sediment transport processes, the P. tabulae form plot with row spacing at 1 × 1 m had a greater effect on soil and water conservation than did other forested plots. 相似文献