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991.
992.
分析了薄木贴面工艺中,木皮起泡主要是由于表面不平、胶水固化程度和薄木含水率等原因所致。并对各个阶段出现起泡的具体情况进行分析,给出处理方法. 相似文献
993.
研究纳米沸石分子筛SHY-DL催化剂上的芳构化反应性能,探索临氢条件、二烯烃含量、反应温度及空速等条件对芳构化反应的影响。在固定床反应器上以炼油厂碳四烃为原料,在反应温度360~450℃、压力2.0MPa、碳四烃液相进料体积空速0.9~1.2h-1的操作条件下,碳四烯烃转化率达99%,干气产率小于2.0%,C5+液相收率为43%~50%,液相产物的RON和MON值为98.8和87.9。在实验室蒸汽热裂解评价装置上,研究碳四烃芳构化副产LPG裂解制乙烯的性能。结果表明,在裂解温度910℃、水油质量比0.45的条件下,LPG裂解的乙烯收率为30.98%,丙烯收率为15.95%,属较好的裂解制乙烯原料。 相似文献
994.
将4种组织差异较大的钼靶材在同一溅射设备,同一溅射工艺下进行磁控溅射试验,对溅射后的靶材表面及薄膜表面、截面形貌及方阻进行检测,讨论并分析靶材微观组织对溅射过程及薄膜形貌、晶向、导电性能的影响.结果表明,不同组织靶材溅射的薄膜表面及截面形貌差异较小;靶材80%的晶粒尺寸小于50 μm时,溅射薄膜沉积速率较快,方阻值的变化较小,薄膜厚度较均匀;钼靶材溅射薄膜的择优均为(110)取向,靶材组织对溅射薄膜的取向影响不大;靶材组织的晶粒均匀细小,晶界所占面积率越大,靶材减薄越均匀,靶材利用率越高. 相似文献
995.
基于ANSYS8.0的蜂窝纸板力学性能研究 总被引:1,自引:0,他引:1
建立了蜂窝纸板的基本力学方程,利用ANSYS8.0对其静态特性进行了计算;得到了面受均布载荷时蜂窝纸板的应力分布图,分析了蜂窝纸芯的应力特点。结果表明:应力集中主要在蜂窝纸板的面纸和芯纸的胶接处,并出现应力峰值,这将对其缓冲性能产生不良的影响。此结论为蜂窝纸板的改进和优化设计提供了参考依据。 相似文献
996.
Li G An T Chen J Sheng G Fu J Chen F Zhang S Zhao H 《Journal of hazardous materials》2006,138(2):392-400
The feasibility study of the application of the photoelectrocatalytic decontamination of high saline produced water containing refractory organic pollutants was investigated in the slurry photoelectrocatalytic reactor with nanometer TiO2 particle prepared with sol-gel method using the acetic acid as hydrolytic catalyst. The efficiency of the photoelectrocatalytic decontamination of produced water was determined with both COD removal from the tested wastewater and the decrease of mutagenic activity evaluated by Ames tests. The experimental results showed that the photoelectrocatalysis is a quite efficient process for decontaminating the produced water, although there are high concentration of salt existed in oilfield wastewater. We found that the COD removal efficiencies by photoelectrocatalytic process are much higher than that of by photocatalytic or electrochemical oxidation individually in the photoelectrocatalytic reactor. The COD removal can be substantially improved by the added H2O2 and the generation of active chlorine from high concentration chlorides in the wastewater. The effects of various operating conditions, such as initial COD concentration, applied cell voltage, catalyst amount and initial pH value of solution, on the photoelectrocatalytic efficiencies, is also investigated in detail. The results showed that when the raw produced wastewater was diluted in a 1:1 (v/v) ratio, there is a highest COD removal efficiency. And the photoelectrocatalytic degradation of organic pollutants in saline water is much favored in acidic solution than that in neutral and/or alkaline solution. 相似文献
997.
998.
Occurrence of nine nitrosamines and secondary amines in source water and drinking water: Potential of secondary amines as nitrosamine precursors 总被引:3,自引:0,他引:3
Due to their high carcinogenicity, the control of nitrosamines, a group of disinfection by-products (DBPs), is an important issue for drinking water supplies. In this study, a method using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry was improved for simultaneously analyzing nine nitrosamines in source water and finished water samples of twelve drinking water treatment plants (DWTPs) in China. The method detection limits of the nine target analytes were 0.2-0.9 ng/L for the source water samples and 0.1-0.7 ng/L for the finished water samples. Of the nine nitrosamines, six (N-nitrosodimethylamine (NDMA), nitrosodiethylamine (NDEA), N-nitrosomorpholine (NMor), N-nitrosodi-n-butylamine (NDBA), N-nitrosomethylethylamine (NMEA), and N-nitrosodiphenylamine (NDPhA)) were detected. The total nitrosamine concentrations in source water and finished water samples were no detection-42.4 ng/L and no detection-26.3 ng/L, respectively, and NDMA (no detection-13.9 ng/L and no detection-20.5 ng/L, respectively) and NDEA (no detection-16.3 ng/L and no detection-14.0 ng/L, respectively) were the most abundant. Meanwhile, the occurrence of nine secondary amines corresponding to the nine nitrosamines was also investigated. All of them except for di-n-propylamine were detected in some source water and finished water samples, and dimethylamine (no detection-3.9 μg/L and no detection-4.0 μg/L, respectively) and diethylamine (no detection-2.4 μg/L and no detection-1.8 μg/L, respectively) were the most abundant ones. Controlled experiments involving chloramination of four secondary amines confirmed that dimethylamine, diethylamine, morpholine and di-n-butylamine in water can form the corresponding nitrosamines, with diethylamine and morpholine showing significantly higher yields than dimethylamine which has already been identified as a precursor of NDMA. This study proved that diethylamine, morpholine and di-n-butylamine detected in raw water would be one of the important the precursors of NDEA, NMOR and NDBA, respectively, in drinking water. 相似文献
999.
火工药剂与金属桥丝接触,在高温、高湿条件下贮存一定时间后两者是否相容,用电镜观察其金属表面的腐蚀形态(面积、深浅),以此来判断金属桥丝与火工药剂的相容性。 相似文献
1000.
水经磁场处理后,某些物理化学性质会发生变化。由于水对环境条件的影响极为敏感,准确地实验测定这些变化碰到了不少难以克服的困难。因此,文献上所报道的数据一致性较差。本工作采用比较法,对二次蒸馏水经过不同磁场强度处理后,其表面张力的变化进行了初步的实验研究和讨论。 相似文献