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101.
Hyejin Yang Young-Chul Lee Kyoung-Sik Han Harjinder Singh Minseok Yoon Ji-Hae Park Chang-Won Cho Suengmok Cho 《Food chemistry》2013
Kiwifruit is one of the most popular fruits worldwide, and it has various biological properties, including antioxidant, anti-allergic, and cardiovascular protective effects. The peel of kiwifruit, which is a by-product of processing, is a good source of flavonoids; however, its bioactivity has not been widely investigated. In this study, we evaluated the hypnotic effects of green (GRPE, Actinidia deliciosa) and gold (GOPE, Actinidia chinensis) kiwifruit peel ethanol extracts and their solvent fractions, and the possible underlying mechanisms. Oral GRPE and GOPE administration (125–1000 mg/kg) produced a dose-dependent decrease in sleep latency and an increase in sleep duration in pentobarbital-treated mice. Among three different solvent fractions of GRPE and GOPE, ethyl acetate (EA) fractions had the greatest effect on sleep duration at 250 mg/kg. The total flavonoid contents of solvent fractions were proportional to sleep duration. Like diazepam (a GABAA–benzodiazepine (BZD) receptor agonist), the hypnotic effects of GRPE, GOPE, and their EA fractions were fully inhibited by flumazenil (a GABAA–BZD receptor antagonist). These results suggest that potentiation effects of GRPE and GOPE on pentobarbital-induced sleep in mice may be modulated by a GABAergic mechanism. 相似文献
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利用超临界乙醇修饰纳米Al2O3,得SCE-Al2O3,使其表面沉积活性基团;以4,4′-二氨基二苯甲烷双马来酰亚胺(BMI)为基体、3,3′-二烯丙基双酚A(BBA)和双酚A双烯丙基醚(BBE)为活性稀释剂、聚醚砜(PES)为增韧剂、SCE-Al2O3为改性剂,通过原位聚合法合成了SCE-Al2O3/PES-BMI-BBA-BBE复合材料。采用SEM和FTIR观察分析了SCE-Al2O3纳米粒子和PES的增韧机制。结果表明:SCE-Al2O3纳米粒子处理时间不宜过长,5min为宜;FTIR显示在3 457cm-1附近的—OH吸收峰增强,说明粒子表面沉积了活性基团—OH;PES与BMI-BBA-BBE呈现两相结构,PES树脂以"蜂窝"状均匀分散在聚合物基体BMI-BBA-BBE中,PES用量增加会使其粒子尺寸增大,适宜用量为5wt%。SCE-Al2O3/PES-BMI-BBA-BBE复合材料的耐热性能测试结果显示:PES树脂会使材料的热分解温度降低,但SCE-Al2O3会提高材料的耐热性能,4wt%SCE-Al2O3/PES-BMI-BBABBE的热分解温度为444.41℃,较基体树脂提高了20.52℃,600℃时残重率为47.64%,提高了7.09%。 相似文献
104.
This study explores how two different cellulosic ethanol production system configurations (distributed versus centralized processing) affect some aspects of the economic and environmental performance of cellulosic ethanol, measured as minimum ethanol selling price (MESP) and various environmental impact categories. The eco-efficiency indicator, which simultaneously accounts for economic and environmental features, is also calculated. The centralized configuration offers better economic performance for small-scale biorefineries, while the distributed configuration is economically superior for large-scale biorefineries. The MESP of the centralized configuration declines with increased biorefinery size up to a point and then rises due to the cost of trucking biomass to the biorefinery. In contrast, the MESP in the distributed configuration continuously declines with increasing biorefinery size due to the lower costs of railroad transportation and the greater economies of scale achieved at much larger biorefinery sizes, including biorefineries that reach the size of an average oil refinery—about 30,000 tons per day of feedstock. The centralized system yields lower environmental impacts for most impact categories than does the distributed system regardless of the biorefinery size. Eco-efficiency analysis shows that the centralized configuration is more sustainable for small-scale biorefineries, while the distributed configuration with railroad transport is more sustainable for large-scale biorefineries. Compared with gasoline from petroleum, cellulosic ethanol fuel offers sustainability advantages for the following environmental impact categories: fossil energy consumption, global warming, human health impacts by particulate matter, ozone layer depletion, ecotoxicity, human health cancer, and human health non-cancer, depending somewhat on the biorefinery sizes and the system configurations. 相似文献
105.
Sugar beet juice can serve as feedstock for ethanol product due to its high content of fermentable sugars and high energy output/input ratio. Batch ethanol fermentation of raw juice and thick juice proved that addition of mineral nutrients could not improve ethanol concentration, but could accelerate the fermentation rate. Fermentation of thick juice with an initial pH of 9.1 did not affect the fermentation process. The continuous ethanol fermentation of raw juice was performed at 35 °C with a dilution rate of 0.3 h−1, resulting in ethanol concentration, ethanol yield and productivity of 70.7 g L−1, 89.8% and 21.2 g L−1 h−1, respectively. A two-stage reactor was used in the continuous ethanol fermentation of thick juice by feeding fresh yeast cells into the second reactor. This process was stable at a total process dilution rate of 0.11 h−1 with an overall sugar concentration of 190 g L−1 in the influent. The ethanol concentration was kept at approximately 80 g L−1, corresponding to ethanol yield of 82.5% and productivity of 8.8 g L−1 h−1. 相似文献
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109.
Behzad Satari Keikhosro Karimi Mohammad J. Taherzadeh Akram Zamani 《International journal of molecular sciences》2016,17(3)
The potential of two zygomycetes fungi, Mucor indicus and Rhizopus oryzae, in assimilating citrus waste free sugars (CWFS) and producing fungal chitosan, oil, and protein as well as ethanol was investigated. Extraction of free sugars from citrus waste can reduce its environmental impact by decreasing the possibility of wild microorganisms growth and formation of bad odors, a typical problem facing the citrus industries. A total sugar concentration of 25.1 g/L was obtained by water extraction of citrus waste at room temperature, used for fungal cultivation in shake flasks and airlift bioreactor with no additional nutrients. In shake flasks cultivations, the fungi were only able to assimilate glucose, while fructose remained almost intact. In contrast, the cultivation of M. indicus and R. oryzae in the four-liter airlift bioreactor resulted in the consumption of almost all sugars and production of 250 and 280 g fungal biomass per kg of consumed sugar, respectively. These biomasses correspondingly contained 40% and 51% protein and 9.8% and 4.4% oil. Furthermore, the fungal cell walls, obtained after removing the alkali soluble fraction of the fungi, contained 0.61 and 0.69 g chitin and chitosan per g of cell wall for M. indicus and R. oryzae, respectively. Moreover, the maximum ethanol yield of 36% and 18% was obtained from M. indicus and R. oryzae, respectively. Furthermore, that M. indicus grew as clump mycelia in the airlift bioreactor, while R. oryzae formed spherical suspended pellets, is a promising feature towards industrialization of the process. 相似文献
110.
以Fe-PGMs合金电解精炼产生的废电解液为原料,无水乙醇作为溶析剂,使用溶析结晶法从废电解液中将硫酸亚铁结晶析出。考察了溶析时间、乙醇与水溶液体积比、溶析温度、搅拌速度、陈化时间、无水乙醇滴加方式对硫酸亚铁结晶率的影响。结果表明,在溶析时间60 min、无水乙醇与水溶液体积比为1:1、溶析温度10 ℃、搅拌速度200 r/min、陈化时间60 min、乙醇滴加方式为逐滴加入时硫酸亚铁结晶率达到最大92.98%。此工艺避免了电解过程中废电解液对环境的污染,实现了电解Fe-PGMs合金中电解液及Fe-PGMs合金酸浸液的循环利用。 相似文献