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121.
以环氧丙烯酸酯与呋喃胺/环氧树脂的互穿聚合物网络(IPN)为基料,制备了耐温、抗冲击性能优良的防腐蚀涂料。讨论了环氧丙烯酸酯的用量对涂料各种性能的影响。试验表明,环氧丙烯酸酯的用量为30%,采用E-51环氧树脂与呋喃胺树脂配合时,漆膜的综合性能较优。  相似文献   
122.
Ismail Koyuncu 《Desalination》2002,143(3):243-253
In this study, DS5 DK type nanofiltration membranes were tested to recycle the reactive dye bath effluents. Reactive black 5 (RB5), reactive orange 16 (RO16), reactive blue 19 (RB19) and NaCl were used in the experiments to prepare the synthetic dye and salt mixtures. Effects of feed concentration, pressure and cross flow velocity on the permeate flux and color removal were investigated. Permeate flux increased with increasing pressure for all NaCl solutions. Dye concentration had a significant effect on flux values. Under the fixed NaCl concentrations the flux decreased with increasing dye concentrations. Dye rejections greater than 99% were achieved. Permeate was almost colorless. A gel layer formed by the rejected dye on membrane surface operates as a resistance to the permeation of dyes due to complete rejection of high molecule weight dyes, especially for the low salt concentrations. The presence of salt concentration has an interesting effect on color removal. Color removal decreased with increasing salt concentration. Cross flow velocities had also a significant effect on flux values. The dye formed agglomerates at high NaCl concentrations. High cross flow velocities decreased this effect.  相似文献   
123.
防沉剂对铜系导电涂料性能的影响   总被引:8,自引:2,他引:8  
研究了有机膨润土防沉剂对铜系导电涂料的沉降率、黏度、触变性、涂层导电性及显微形态的影响。研究表明,有机膨润土可解决铜-环氧涂料的填料沉降问题。  相似文献   
124.
Ever since seawater desalination has been applied on an industrial scale, and particular in the countries of the Arabian Gulf, the application of desalination processes in dual-purpose facilities—water and power—as a hybrid configuration has been discussed in many feasibility investigations and also planning concepts. It is above all the combination of reverse osmosis with thermal processes that has found increasing interest with the aim of ensuring, as economically as possible, uniform water supplies under the specific, greatly varying load conditions in the Gulf countries. Such design concepts for hybrid configurations encompass straightforward structures with a low degree of coupling between membrane and thermal desalination processes, but range up to very complex configurations with strong interconnections on both the water side and thermally, as well as with several desalination processes connected in series or in parallel. Classical hybrid concepts in which the permeate from an RO desalination component is mixed with distillate from thermal desalination have already been implemented in Saudi Arabian dual-purpose plants, like Jeddah and Yanbu-Medina. Although hybrid systems of greater complexity have been addressed in many design studies and publications, up to now none has been brought to fruition. Coming into consideration asthe design basis for determining the capacity shares of the various desalination processes operated in a hybrid configuration are: arrangement of thermal cycle of the power plant component; water/power ratio of the dual-purpose seawater desalination and power plant; provision of undiminished water production of the desalination plant as electricity generation varies; provision of a specified drinking water quality with regard to composition and salt content; combination of all these aspects. Also gaining in importance are concerns of environmental pollution and sustainable development when selecting seawater desalination and power plant configurations, as well as their optimization when considering desalination and electricity generation as a whole. In the practical design of hybrid membrane and thermal systems, aspects come to light, though, that restrict linking of the two systems and joint utilization of facilities, as conceived in studies and conceptual design investigations. This applies both for common utilization of intakes and the use of heated up cooling water from thermal processes as a feed stream for the RO part of the desalination process. Additionally, requirements of drinking water composition, particularly chloride content, TDS and compliance with a specific residual content of boron, influence specifically the design of the membrane process part and its share in the total desalination capacity. Such practical aspects have greatly influenced the design and configuration of the Fujairah hybrid plant for which, from a total desalination capacity of 100 MIGD (454,600 m3/d), the share of 37.5 MIGD (170,500 m3/d) makes its seawater RO plant the biggest currently being constructed anywhere in the world. From the findings of the engineering of this plant and the idea that, by increasing interconnection between the two processes on the water side, it is possible to advance a hybrid configuration of this type with regard to cost optimization in the membrane installation, but also by joint utilization of the intake equipment, perspectives result for applied research efforts over the near and long terms, for example: long-term behavior of membranes at elevated temperatures; tendency for biofouling in membrane process with common utilization of cooling water and brine; influences of such interconnections on the overall availability of the facility. But also for the operation and maintenance organization of such large facilities, consequences can be foreseen for the future development of hybrid plants, particularly for operation management and organisation of the interplay of the different power plant and desalination systems, monitoring of SWRO membrane replacement and cleaning, as well as controlling water quality.  相似文献   
125.
畜禽养殖废水有机物水质水量变化大,有机物、氨氮与磷的浓度较高,直接排放会严重危害环境。通过构建厌氧-好氧序批式反应器(SBR)处理预酸化畜禽养殖废水,分析了不同进水负荷条件下反应器对污染物的去除性能和微生物群落结构的变化规律。结果表明:SBR反应器对高负荷进水中TN、PO3-4—P和COD的平均去除率可分别达到64.5%、97.5%和94.5%。反应器出现NH+4—N和NO2—N亚硝酸同时积累的短程硝化现象,这可能与高进水负荷对氨氧化菌和亚硝酸盐氧化菌的活性和种群的影响有关。与乙酸盐相比,以丙酸盐作碳源时污泥的强化生物除磷活性更高。随着进水负荷的增大,聚糖菌(GAOs)的相对丰度明显升高。四联球状菌(Tetrasphaera)为反应器中始终占优势的聚磷菌(PAOs),对反应器除磷性能有重要贡献。在高有机负荷条件下,SBR内PAOs与GAOs之间不存在明显的底物竞争关系,系统脱氮除磷性能未受影响。  相似文献   
126.
新一代喷涂聚脲路面标线涂料   总被引:1,自引:0,他引:1  
葛喨  孙凌  张宪康 《涂料工业》2006,36(3):36-38
简述了国内路标漆的发展概况,介绍了聚天冬氨酸酯聚脲路标漆的原理、配方及应用性能。针对目前国内各种路标漆的优缺点,将聚天冬氨酸酯聚脲路标漆与它们进行比较,发现聚天冬氨酸酯聚脲路标漆具有快干、耐磨、反光效果好、施工速度快、重涂性好等优点,特别适用于路面标线涂料的应用。  相似文献   
127.
采用恒电流模式,同时以活性炭纤维(ACF)为阳极和阴极,在无隔膜电解槽中研究了不同电流密度下蒽醌染料活性艳蓝KN-R的电化学脱色。结果表明在1.0~1.5mA.cm-2时,电解槽中发生阳极电氧化和阴极电还原同时进行的成对电解脱色。成对电解的发生,可以提高电解槽的工作处理能力。当电流密度为1.1mA.cm-2时,脱色率达到87%。  相似文献   
128.
通过对树脂、颜料、分散剂和混合溶剂的选择和定量,合成了通用色母。用指研法检验色母的分散稳定性,用倾流法或指擦法检验颜料的流动性,介绍了影响色母分散稳定性和颜料流动性的因素和原理,着重讨论了汽车修补涂料色母的单色浆微脂技术中分散剂的复配分散。  相似文献   
129.
核工业专用橡胶型可剥掩蔽涂料的研制和应用   总被引:5,自引:0,他引:5  
介绍了核电、核能工业专用橡胶型可剥掩蔽涂料的研制和应用,选用新型含有苯基的聚丁二烯弹性体为基料,加入耐酸、耐辐照的颜填料和防黏剂、偶联剂及N-13a固化剂配成JF系列常温固化的核电、核能工业专用橡胶型可剥掩蔽涂料,该涂料耐酸碱、耐辐照,防污性能优良。  相似文献   
130.
采用新兴的绿色坏保技术-超临界水氧化反应法,对含偏二甲肼的航天推进剂废水进行了处理研究。试验结果表明,采用小型的管道式连续SCWO反应系统能够迅速将该类推进剂废水中的毒害成分-偏二甲肼彻底分解为无害的CO2和N2。反应温度和反应停留时间是影响偏二甲肼去除率的主要因素,当反应温度超过500℃,停留时间达到95s时,偏二甲肼的COD去除率大于99.9%,完全达到了国家航天推进剂水污染物排放标准的要求。  相似文献   
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