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91.
Soil salinity, poor soil structure and macronutrient deficiencies are three important limitations responsible for poor crop yields in coastal saline soils. Here we used humic fertilizer and vermicompost to ameliorate salt-induced stress by regulating the soil bacterial community and aggregates in different growth stages of winter wheat. Soil salinity, aggregates, nutrient availability, the soil bacterial community from next-generation high-throughput sequencing, and wheat yield were determined in this study. The results indicated that humic fertilizer and vermicompost could efficiently alleviate salt accumulation (by 16.8–41.1 and 13.3–42.7%, respectively) in topsoil by inhibiting resalinization and increase the proportion of soil macroaggregates (by 26.7–85.9 and 31.6–105.5%, respectively) in the wheat growth stages. Skermanella, Arthrobacter and Sphingomonas were the dominant genera in the study soil. Humic fertilizer and vermicompost could improve soil total N (by 4.7–15.6 and 2.4–25.2%, respectively), available P (by 15.9 and 7.3–64.4%, respectively), and exchangeable K (by 3.9–18.4 and 0.7–12.1%, respectively) by increasing the abundance of Arthrobacter and Pedobacter, consequently improving shoot biomass (by 41.1 and 52.8%, respectively) and grain yield (by 45.1 and 60.2%, respectively) of wheat. Therefore, vermicompost and humic fertilizer ameliorate salt-induced stress in coastal saline soil through the integrated improvement of soil physical, chemical and biological properties. 相似文献
92.
通过分析新疆地区当前主要提供农机信息化服务的新疆农机信息网的现状,指出该网站在服务功能上的不足和发展上的需求及制约因素,研究阐述了新疆农机信息网的发展趋势,即搭建农机综合信息服务平台。 相似文献
93.
本研究利用Giemsa C-带方法对毛百合(Lilium dahuricum Ker-Gawl)根尖染色体进行了分析。研究结果表明毛百合试管苗的染色体倍性变异丰富,染色体倍性变异包括二倍体(2n=2×=24)、三倍体(2n=3×=36)、四倍体(2n=4×=48)到六倍体(2n=6×=72)。对二倍体毛百合的C-带结果进行分析,其带型公式为:2n=2×=24=2CI++2CI+T+T++6I+2I++2I++2I+T++2I+T++2I+T++2T++2T+。每条染色体上都显示出显著的特征带,而且带纹的深浅差异明显。强带主要集中在长短臂上。因此,GiemsaC-带方法可以将毛百合(L.dahuricum)的每条染色体区分开。 相似文献
94.
Yan Liang Guodong Han He Zhou Mengli Zhao Hennie A. Snyman Dan Shan Kris M. Havstad 《Strength and Conditioning Journal》2009,62(4):328-336
Vegetation features radiating from residential areas in response to livestock grazing were quantified for an arid steppe rangeland in the Keshiketeng Banner, Chifeng Prefecture, in northeastern Inner Mongolia in 2004 and 2006. The aim of this study was to estimate grazing impacts on the vegetation dynamics of these historical grazed ecosystems. Grazing intensities were classified as reference area (RA), light (LG), moderate (MG), and heavy (HG) according to the vegetation utilization across the study area. Rangelands were studied along a grazing gradient, where characteristics of plant communities, heights of dominant species, aboveground vertical structures, and belowground biomass were investigated. Along this grazing gradient, vegetation changed from the original dominant plant species Leymus chinensis (Trin.) Tzvel. to a semi-subshrub species Artemisia frigida Willd. when moving from the reference area (RA) to the region around the settlement. Canopy coverage, aboveground productivity, and the number of perennial species declined as one moved toward the residential area. Heights of five dominant species, except for Stipa grandis P. Smirn., declined with increased grazing intensity. Aboveground vertical structure in the RA treatment showed more resilience than the other treatments. There was no difference in root biomass in the top 1 m of soil (P > 0.05) between the RA treatment and the area immediately around settlement (HG treatment). Generally, we found that the intensity of grazing disturbance did not exceed the tolerance of the rangeland ecosystem within LG treatment. However, vegetative conditions in HG treatment became worse with increased grazing pressure. Rangelands in this arid steppe are under tremendous threat due to excessive forage utilization, which cannot be considered a sustainable practice. 相似文献
95.
论述了285F型柴油机开发中直喷式燃烧系统研制的设计思想、技术措施与试验结果,并就小缸径柴油机采用直喷燃烧技术提出了一些看法。 相似文献
96.
【目的】棉苗经低温胁迫后喷施调节剂,研究不同植物生长调节剂对棉花幼苗低温冷害的修复作用,为棉花幼苗抵御低温冷害提供技术参考。【方法】以棉花品种新陆早57号为材料,采用人工模拟低温方法,在子叶期4℃ 24 h处理后,叶面喷施清水为对照,分别喷施7种不同植物调节剂溶液后,置于25℃ 14 h/10 h(昼/夜)的人工气候箱内恢复,分析不同生长调节剂对棉花幼苗冷害的生长情况和生理生化特征的影响。【结果】与清水处理比较,喷施植物生长调节剂后棉花幼苗的株高增加了5.10%~9.87%,茎粗增加了5.28%~8.71%,主根长增加了5.24%~9.33%,鲜重增加了2.26%~5.98%,干重增加了2.38%~8.61%,冷害指数下降了1.79~5.29个百分点,脯氨酸增加了5.04%~5.58%,可溶性蛋白含量增加了5.07%~5.67%,可溶性糖含量增加了5.05%~5.87%;CAT酶活性增加了2.21%~7.95%。SOD酶活性增加了3.79%~5.56%,POD酶活性增加了2.18%~5.56%。【结论】在低温胁迫后,在常温恢复过程中叶面喷施生长调节剂可有效的提高棉花幼苗叶片的渗透调节能力和抗氧化能力,促进植株生长,修复低温胁迫对植株的伤害,以植物生长调节剂处理提高棉花幼苗抗寒性。其中,调节剂对低温胁迫后棉花幼苗恢复效果的综合作用排序为“阿泰灵”>α-萘乙酸钠>胺鲜脂>“碧护”>复硝酚钠>腐殖酸>黄腐酸钾Ⅱ型>对照。 相似文献
97.
洋芋的贮藏方法单一落后,会因贮藏不当而产生有毒的龙葵素,导致食物中毒。从洋芋的贮藏特性、影响因素、贮藏过程中龙葵素的变化,以及龙葵素的检测、提取及利用、存在问题及展望进行了综述,为洋芋安全贮藏及综合利用提供有益的参考。 相似文献
98.
99.
贝类中副溶血弧菌和沙门氏菌荧光定量PCR快速检测方法的建立 总被引:2,自引:0,他引:2
为适应进口鲜活水产品的快速检验,有必要建立快速检测多种病原生物的方法。本文针对鲜活水产品中常见的副溶血弧菌和沙门氏菌,设计了特异的荧光引物,建立了检测贝类中这两种细菌的荧光定量PCR体系,并进行了特异性与重复性试验。结果表明,在相同的反应条件下,副溶血弧菌和沙门氏菌均得到了特异性扩增,而阴性对照菌株均未见扩增。副溶血弧菌标准曲线在1.53×105~1.53×109拷贝/μL之间、沙门氏菌标准曲线在4.89×106~4.89×1010拷贝/μL之间有较好的线性关系。与传统的检测方法相比较,该荧光定量PCR方法检测贝类中的副溶血弧菌和沙门氏菌更为快速准确,结果直观,可以满足口岸进口水产品快速检测的需要。 相似文献
100.
研究了两步超滤法分离鸡蛋清中卵白蛋白与溶菌酶的可行性。基于超滤机理分析了超滤过程中初始料液体积分数、pH值和跨膜压力等参数对膜通量、透过液蛋白质质量浓度的影响。在考察膜通量变化确定超滤时间的基础上,通过超滤试验获得最佳工艺条件:初始料液体积分数6.0%,pH值2.5,跨膜压力0.12 MPa。超滤产物纯度、回收率较高,卵白蛋白、溶菌酶的纯度分别为85.72%、87.21%,回收率分别为51.36%、62.58%。试验结果表明,两步超滤法可用于鸡蛋清卵白蛋白与溶菌酶的规模化、高效分离。 相似文献