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81.
Meriel Moore-Colyer Denise M. O'Gorman Katherine Wakefield 《Journal of Equine Veterinary Science》2014
Management of the performance horse often incorporates meal feeding of highly digestible starches and reduced access to high-fiber forage. Such regimens are associated with equine gastric ulceration syndrome (EGUS) and can alter hindgut homeostasis. In-feed buffering of gastric contents and promotion of energy derivation from high-fiber forage in the hindgut are therefore desirable properties of a nutritional supplement. A marine-derived, multimineral supplement with known buffering properties containing calcium, magnesium, and short-chain fructo-oligosaccharides (scFOS) was tested under in vitro simulations of equine stomach and hindgut conditions. Six fiber:concentrate diets were incubated for 4 hours with or without the supplement at 37°C in pepsin HCl solution adjusted to pH 4.1 and 2.6. pH was measured at 1, 2, and 4 hours postincubation. Highest overall pH values were observed with the high cereal feeds; however, the supplement significantly increased (P < .001) the pH across all feeds by 0.17 and 0.19 for feeds incubated at pH 4.1 and 2.6, respectively. A gas production technique was used to measure the fermentation of four fiber:concentrate diets with and without additional supplement, using equine feces as the microbial inoculum. Addition of the supplement decreased (P < .05) the lag time and increased the initial fermentation rate, although as the incubation continued, this effect was reduced. These results demonstrate that the supplement had a significant buffering action for 4-6 hours under simulated in vitro stomach digestion conditions and also stimulated in vitro hindgut fermentation activities. 相似文献
82.
为比较不同品种油橄榄叶果之间多酚含量的差异,以云南引种的16个品种油橄榄叶样及13个品种的果渣样为原料,采用4因素3水平正交试验设计,选出微波辅助提取油橄榄多酚物质最优水平组合为:萃取功率为600 W、萃取时间为20 min、萃取温度为120℃、乙醇-水溶液浓度为40%,以此为微波萃取工艺条件,提取油橄榄叶样及果渣样中多酚物质,并测其含量。结果表明,叶样多酚含量鄂植8号中的最低,为1.02%,城固53中最高,为8.29%;果渣样品中多酚含量,阿斯最低,为0.64%,而莱星最高,为1.56%,油橄榄叶样中多酚含量平均值(4.21%)大于果渣中多酚平均含量(1.10%)。实验结果为从油橄榄中获取天然抗氧化剂,以延伸油橄榄产业链提供理论依据。 相似文献
83.
不同提取方法对紫苏叶挥发性成分的影响 总被引:1,自引:0,他引:1
[目的]利用不同方法提取紫苏叶中挥发性成分,为紫苏叶的综合利用提供参考.[方法]分别采用动态逆流提取法、微波提取法和超声波提取法提取紫苏叶中的挥发性成分,并结合GC-MS分析和三角评价进行对比分析.[结果]动态逆流提取法共检测17种紫苏叶挥发性成分,集中在后阶段出峰,主要是沸点相对较高的难挥发性成分;微波提取法共检测19种紫苏叶挥发性成分,其出峰时间集中在中间阶段,主要是中等挥发性成分;超声波提取法共检测25种紫苏叶挥发性成分,其出峰时间比较靠前,主要是易挥发的小分子化学成分.3种紫苏叶提取物香气类型基本一致,但超声波提取物香气强度要明显优于其他两种方法.[结论]超声波提取技术更适合于紫苏叶易挥发性成分的提取. 相似文献
84.
微波消解ICP-MS法同时测定土壤中的多种重金属元素研究 总被引:1,自引:0,他引:1
提出了微波消解IC P-M S法测定土壤中13种重金属元素的方法。采用硝酸-盐酸-氢氟酸-高氯酸体系消解,稀释定容后用ICP-MS对溶液进行元素的测定,在优化仪器工作参数后,以内标(Sc、Ge、Bi、In、Rh)进行校正。元素检出限为0.006~0.2μg/L ,测定国家标准物质四川盆地土壤成分分析标准物质GBW07428中的元素,测定值与标准值或参考值基本一致,该方法快速、简便、准确,适于土壤中多种微量元素的测定。 相似文献
85.
研究了微波法提取虎杖中的白藜芦醇,通过正交实验初步确定微波功率、乙醇浓度、料液比、提取时间4个因素对提取效果的影响并确立最佳的提取工艺条件为:微波功率700W ,乙醇浓度70%,料液比1∶20,微波时间20min。 相似文献
86.
针对目前针叶类林木松树厌氧发酵前预处理效果差、成本高的问题,在添加食品废弃物的条件下,研究好氧堆肥方法对松木屑(6.35 mm、9.53 mm和12.70 mm)和食品废弃物混合物料的预处理效果,以及对后续干式厌氧发酵过程的影响。研究结果表明,好氧堆肥过程对松木屑的预处理效果明显,但随着松木屑粒径的增大预处理效果降低;经堆肥预处理后物料的厌氧发酵原料的VS产气率均维持在199~215 L/kg范围内,约为未预处理组的1.4倍,而且发酵后物料中的VFA总量均维持在24.5左右,约为未堆肥预处理组的1.5倍,后续产气潜力更大。 相似文献
87.
海洋沉积物中重金属含量测定样品前处理方法研究 总被引:9,自引:0,他引:9
采用正交设计试验法对测定海洋沉积物中重金属含量的样品前处理方法进行了比较研究。结果表明。在王水、氢氟酸、高氯酸消解体系下,采用微波消解一原子吸收分光光度法测定重金属含量,省时,试剂用量少,结果准确,重现性好。 相似文献
88.
The activity and capacity (activity × tissue weight) of digestive carbohydrases (total carbohydrase, α‐glucosidase, α‐amylase) was examined in vitro under a range of (more realistic) incubation temperatures (5, 18 and 25°C) and pH (7.6) more likely to be encountered during rearing, along the digestive tract of important teleost species for aquaculture (Dicentrarchus labrax, Sparus aurata, Oreochromis aureus, Oncorhynchus mykiss and Salmo salar). Results indicate, among other things, an overestimation of digestive carbohydrase levels when performing assays at 37°C, a different effect of temperature on digestive enzyme performance along the digestive tract of examined species, and the increased importance of α‐glucosidase towards carbohydrate digestion. Implications regarding the capacity of each species for carbohydrate digestion in nature, as well as feed manufacturing, are discussed. 相似文献
89.
90.
Biogas production from grassland biomass harvested during landscape management may help to maintain species‐rich grassland biotopes, but extensive management and late harvests often result in low‐quality biomass. Biogas production from the vegetation of Alopecuretum pratensis, Molinietum caeruleae and Caricetum gracilis, three typical grassland biotopes in north German nature reserves, was investigated in relation to harvest date. In addition, the A. pratensis vegetation was investigated for ensiling and the application of bacterial silage additives. Results indicate that biogas production might be a reasonable utilization pathway for grassland biomass from landscape management if the first cut occurs up to late summer. Methane yields of grassland biomass decreased substantially with later harvest, from up to 309 lN kg?1 organic dry matter (ODM) in May to below 60 lN kg?1 ODM in February, in correlation with increasing crude fibre contents. Caricetum gracilis vegetation was the least suitable feedstock for biogas production. It showed a rapid decline in methane yields with later harvest and 25% lower methane yields compared with other types of grassland vegetation. Application of silage additives is recommended for adequate preservation of grassland biomass from landscape management by ensiling. Addition of homofermentative lactic acid bacteria improved acidification during ensiling if sufficient fermentable sugar was available. The use of inoculant and molasses enhanced methane yields by 3–55%. Additional carbohydrate source is necessary to ensure proper ensilage when grasses are harvested after late autumn. 相似文献