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981.
试验研究了不同氧化工艺与铁盐混凝工艺联合处理矿井水中砷的效果。原水p H值为7.67,砷质量浓度为1 mg/L,采用铁盐混凝法处理时,Fe与As的质量比为6∶1、反应时间为30 min,砷的去除率为62%;当其与空气氧化法联合处理时,Fe与As的质量比为6∶1、反应时间为30 min、曝气量为0.05 m~3/h,砷的去除率为69%;当其与过氧化氢氧化法联合处理时,Fe与As的质量比为6∶1、反应时间为5 min、过氧化氢用量为0.01 m L/L,砷的去除率为99%。试验结果表明:引入氧化体系有助于含砷矿井水的处理,提高了砷的去除率;采用Fenton氧化体系与铁盐混凝法联合处理工艺,降低了铁盐药剂用量,提高了砷的去除率,缩短了反应时间。 相似文献
982.
在CaCl_2熔盐中,采用熔盐电解法还原钛铁矿。在槽电压分别为3.0V和3.1V、825~900℃时,研究了不同槽电压及电解温度对钛铁矿电解还原的影响,并对钛铁矿电解脱氧过程进行了讨论。结果表明,在电解过程中铁优先还原,反应区中铁含量高时易形成TiFe_2合金;槽电压对钛铁矿电解产物有重要影响;提高反应温度有利于促进铁钛的互扩散合金化过程。 相似文献
983.
本文基于四值代数,提出三值电路的统一理论电路三要素(信号,网络和负载)理论,该理论表明:门级与开关级电路间,开关级电路结构间,动态与静态电路间存在简单的转换关系,依照这个关系很容易由三值函数式设计出三值电路,尤其能基于一个电路方程同时推出三值动态和静态电路。 相似文献
984.
Lehua Zhang Bart De Gusseme Lankun Cai Peter De Schryver Massimo Marzorati Nico Boon Piet Lens Willy Verstraete 《Water and Environment Journal》2011,25(1):106-115
Hydrogen sulphide emission in sewers is associated with toxicity, corrosion and odour and also yields considerable costs. The purpose of this study was to evaluate whether the soluble sulphide concentration in raw sewage can be controlled by dosing an iron‐rich waste‐activated sludge (WAS) or an iron‐rich aerated waste‐activated sludge (AWAS). An average soluble sulphide elimination of 99% was achieved at an iron‐rich AWAS to sewage ratio (v/v) of 16%, whereas dosage of iron‐poor AWAS at the same ratio decreased the soluble sulphide in the raw sewage by only 53%. Our lab‐scale tests suggest that dosing iron‐rich AWAS to sewage did not affect the chemical oxygen demand (COD) and total ammonia nitrogen (TAN) removal as well as the nitrification efficiency in the receiving activated sludge system. The results indicate that iron‐rich AWAS dosage is a feasible technique to remediate the sulphide problem in sewers. 相似文献
985.
Federica Sodano Prof. Barbara Rolando Prof. Francesca Spyrakis Mariacristina Failla Prof. Loretta Lazzarato Dr. Elena Gazzano Prof. Chiara Riganti Prof. Roberta Fruttero Prof. Alberto Gasco Prof. Salvatore Sortino 《ChemMedChem》2018,13(12):1238-1245
A few compounds in which the nitric oxide (NO) photodonor N‐[4‐nitro‐3‐(trifluoromethyl)phenyl]propane‐1,3‐diamine is joined to the mitochondria‐targeting alkyltriphenylphosphonium moiety via flexible spacers of variable length were synthesized. The lipophilicity of the products was evaluated by measuring their partition coefficients in n‐octanol/water. The obtained values, markedly lower than those calculated, are consistent with the likely collapsed conformation assumed by the compounds in solution, as suggested by molecular dynamics simulations. The capacity of the compounds to release NO under visible light irradiation was evaluated by measuring nitrite production by means of the Griess reaction. The accumulation of compounds in the mitochondria of human lung adenocarcinoma A549 cells was assessed by UPLC–MS. Interestingly, compound 13 [(9‐((3‐((4‐nitro‐3‐(trifluoromethyl)phenyl)amino)propyl)amino)‐9‐oxononyl) triphenylphosphonium bromide] displayed both the highest accumulation value and high toxicity toward A549 cells upon irradiation‐mediated NO release in mitochondria. 相似文献
986.
987.
988.
Amira Mohamed Mohsen Marwa Hasanein Asfour Abeer A. A. Salama 《Drug development and industrial pharmacy》2017,43(12):2043-2054
The main objective of the present work was to formulate, characterize, and evaluate silymarin (SM)-loaded bilosomes, compared to conventional liposomes, aiming at increasing the hepatoprotective activity of the drug. SM-loaded bilosomes were prepared by thin film hydration technique employing soybean phosphatidyl choline (SPC) and different bile salts. After being subjected to different methods of characterization, SM-loaded bilosomes were investigated for their hepatoprotective activity, in CCl4 hepatointoxicated rat model. The developed SM dispersions exhibited an entrapment efficiency ranging from 21.80?±?2.01 to 84.54?±?2.51% and a particle size diameter in the nanometric dimensions (413?±?96.9 to 686.9?±?62.38?nm), with a negative zeta potential values (<–45?mV). In vitro release study revealed a lower cumulative amount of drug released from the developed formulae, compared to free drug. Ex vivo intestinal uptake study, performed using confocal laser scanning calorimetry, revealed the superiority of bilosomal uptake compared to that of liposomes. In vivo studies revealed an enhanced hepatoprotective effect of SM-loaded bilosomes/liposomes compared to free drug. These results were in good correlation with histopathological examination. These findings support the potential use of bilosomes for improving the hepatoprotective activity of SM via oral administration. 相似文献
989.
Recently, long-wavelength photoinitiating systems for cationic photopolymerization (LWCPIs) have attracted growing interest due to the wide applications of visible light emission sources. The approaches used to expand the wavelength range of the cationic photoinitiating (CPI) system range from designing new onium salts with long-wavelength absorbing chromophores to photosensizing conventional onium salts with various visible light photosenzitizers or free radical sources. In this review, the initiating mechanisms and characteristics of each approach are introduced, and the latest developments are highlighted. Based on analysis and comparison of recent progress, forthcoming developments are proposed as well. 相似文献
990.