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排序方式: 共有1408条查询结果,搜索用时 15 毫秒
1.
This work represents the efficiency of a solar desalination pond as a second stage of proposed zero discharge desalination processes to reach fresh water and also concentrated brine from the effluent wastewater of the desalination unit of Mobin petrochemical complex. So a solar desalination pond is constructed after a pretreatment unit to concentrate the softened wastewater to about 20 wt%. The concentrated wastewater is as a suited feed for a forced circulation crystallizer. During one year, the effects of major parameters such as ambient temperature and solar insolation rate are investigated, experimentally. specific gravity in each layer of concentrated brine wastewater is evaluated. Also, evaporation rates are calculated theoretically and are verified by experimental data. Theoretical values predict evaporation rate accurately. Results show good agreement with experimental data. According to results, maximum evaporation rate is 5 l/m2 day when the insolation rate is about 24,602 kJ/m2 day Solar energy absorption factor on June is max. Also, experimental results show the best proposed time to gain highest thermal energy is on spring therefore performance efficiency of solar desalination pond promote on spring comparing with the other months. Extracted data for specific gravity prove the bottom of solar desalination pond, layer 1, is best zone for energy saving and energy utilization.Also, theoretical values of evaporation rate are calculated according to measured temperatures and related mass conservation equation. Comparison between theoretical and experimental values shows dusty weather, humidity and wind velocity affects on heat transfer coefficients approximately. So, deviations between theoretical data and measured values can be explained. Results show good agreements with experimental data.  相似文献   
2.
为了去除玉米糖肽溶液中过多的盐分,采用相对分子质量200 纳滤膜对具有抗氧化活性的玉米糖肽溶液进行脱盐处理,通过对膜通量以及玉米糖肽溶液的Na +质量分数、脱盐率、电导率、短肽回收率和纳滤后产物自由基清除率和Fe 2+ -螯合率等参数的研究,确定玉米糖肽溶液的纳滤脱盐工艺。结果表明,利用相对分子质量200纳滤膜对玉米糖肽溶液脱盐的工艺条件为:在压力2.0 MPa、温度20 ℃条件下连续纳滤5次,每次体积浓缩倍数为2。经5次纳滤后,玉米糖肽截留液的电导率降低60.87%,脱盐率和短肽回收率分别为81.60%和96.97%,羟自由基清除率从11.25%提高到15.85%,而1,1-二苯基-2-三硝基苯肼自由基清除率和Fe2+-螯合率分别降低11.83%和46.07%。同时,相对分子质量200纳滤膜还可以除去糖基化反应体系中55.54%未反应的D-氨基葡萄糖,起到脱盐、脱糖和浓缩的三重作用。  相似文献   
3.
超滤用于海水淡化预处理的研究进展   总被引:6,自引:1,他引:5  
良好的预处理是保证反渗透(RO)装置长期稳定运行的关键要素之一.与传统预处理技术相比,UF预处理能够有效降低海水的SDI、浊度和TOC等,为RO装置提供优良、稳定的进水,增强RO膜的可靠性.详细评述了近年来国内外采用UF技术作为RO淡化预处理过程的研究和应用进展.此外,对UF膜的污染和控制对策研究进展也作了评述.UF作为膜法海水预处理技术已成为该领域的发展趋势.  相似文献   
4.
The relationships between electrode absorptive capacity and solution temperature,concentration and electrode potential were investigated by theoretic analysis and experiments.The results show that the charge of electric double-layer on electrode interface is very sensitive to temperature and electrode potential in the electroadsorption process.For the specific electrical adsorption device,the electrode potential must be controlled to avoid the electrolytic reaction.  相似文献   
5.
杨威 《广东化工》2011,38(6):300-301
文章介绍了高速直流电脱盐和高效交直流电脱盐组合式工艺在惠炼常减压装置的实际应用情况,通过实践数据验证,这套工艺的脱盐脱水效果较好,能耗状况较佳,表明这套工艺是一套经济可靠、性能优良的工艺.  相似文献   
6.
孙肖  易楠  高溪 《安徽化工》2011,37(4):55-56,77
中海油天津化工研究设计院设计开发的缓蚀阻垢水处理技术,能够使腐蚀性水质的海水淡化水成功地作为补充水应用于循环冷却水系统,保证循环水稳定运行,确保正常生产。  相似文献   
7.
介绍了鞍钢股份有限公司鲅鱼圈钢铁分公司120 t/d反渗透海水淡化示范工程的总体设计、设备研制、选型及工艺。对反渗透海水淡化系统进行了连续运行和测试,结果表明,该系统运行参数稳定,设备运行正常,性能指标达到设计要求,淡化后的海水达到了GB5749-2006国家饮用水标准。  相似文献   
8.
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   
9.
建立风储海水淡化孤立微电网对于海岛地区可再生能源的利用、淡水资源的供给都具有重要意义。搭建基于PXI和PC的实时仿真平台,对风储海水淡化孤立微电网运行与控制进行了实时仿真试验研究。介绍了实时仿真平台的搭建、各部分数字仿真模型的建立并详细阐述了孤立微电网协调控制方案。该协调控制方案利用海水淡化负荷的可控性,协调控制超级电容、锂电池储能,维持孤立微电网的功率平衡与稳定。最后,通过实时仿真实验验证了所提出的协调控制方案的可行性。  相似文献   
10.
贺烽  韩继先 《水泥工程》2015,28(4):72-75
近年来,随着河砂开采的限制和资源的匮乏,海砂在沿海地区建筑行业中的使用越来越普遍。介绍了我国的海砂资源情况和海砂性能特征,并分析了海砂中盐类尤其是氯盐和杂质对混凝土耐久性能的影响。海砂通过淡化处理,可以很好地去除其中有害的盐类和杂质,从而可确保淡化后的海砂在建筑工程中的安全可靠应用。  相似文献   
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