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911.
中国五矿长沙矿山研究院研发的氢氧能源机由IGBT逆变电源、自动控制系统、氢氧发生功能模块、主水箱、副水箱、水气分离系统、压力自动侦测系统、冷却系统、介质循环系统、防回火系统等功能单位系统组成。其工艺和技术都高于行业标准,安全性能很高,切割工艺的适应性较强,且更加经济、安全。可在替代高能耗、高污染的传统燃气设备在钢铁切割、汽车发动机除碳、医疗垃圾焚烧、锅炉催化燃烧、针剂拉丝封口、民用燃气等多个领域得到推广和普遍应用。 相似文献
912.
The Flemish renewable electricity support system has struggled to address a number of problematic issues in the past. These included excessive profit margins and general malfunctioning of the green certificate market, as well as a lack of qualification of various existing renewable energy technologies. The Flemish government responded to these issues by introducing major reforms in 2013, including “banding” to differentiate the support for various technologies. However, reliable methods for differentiating renewable electricity technologies and calculating support levels have not been sufficiently developed. The main objective of the 2013 reforms was to reduce support costs, but application of German feed-in tariffs on 18 reference technologies has shown that most projects in Flanders continue to receive high levels of support. The 2013 reforms did not succeed in addressing malfunctioning of the green certificate market. On the contrary, the confidence of investors in renewable electricity plants has decreased as the terms of support can be altered retroactively by adjusting remuneration levels and through political interventions. Future adaptations are likely to be made which will further decrease the overall stability and effectiveness of the system. 相似文献
913.
利用炼化企业低温余热的低温多效蒸馏海水淡化技术 总被引:1,自引:0,他引:1
简要介绍了炼化企业的低温余热回收利用现状,阐述了目前低温多效蒸馏海水淡化技术(LT-MED)的发展水平、技术特点和发展趋势.以某沿海石化企业为例,对利用低温余热LT-MED技术的技术方案和成本进行了分析,得出的结论是:炼化企业低温余热回收系统的回收热水温度一般为95~100℃,取热温度为65~70℃,与MED技术的运行参数较为吻合;用MED技术生产的一级除盐水价格一般在4~6元/m3,而沿海炼化企业的一级除盐水的价格普遍高于7元/m3,视全厂所需的除盐水量适时进行建设,应该可以取得较好的收益. 相似文献
914.
Sonication is a well‐known sludge pretreatment technique with the advantages of simple operation and high efficiency. However, it is an energy‐intensive process. Hence, it is very important to predetermine its sludge disintegration efficiency at varying pretreatment conditions in order to minimize the ultrasonic energy consumption. In this study, it was found that the ultrasonic sludge disintegration occurred in two stages: rapid and subsequent slow disintegration stages. For this reason, it was aimed to develop a simple and accurate mathematical model to describe the two‐stage sludge disintegration as a function of pretreatment conditions. Sludge concentration and ultrasonic density along with sonication period were involved in this model as independent variables. It was determined that the mathematical model can predict accurately the degree of sludge disintegration. Thus, the proposed model was seen to be very useful for evaluating the disintegration efficiency and/or for process design using the operating parameters under different conditions. 相似文献
915.
Argillaceous rocks are being considered as potential host rocks for deep geological disposal. For the research work in DECOVALEX-2011, 5 participant research teams performed simulations of a laboratory drying test and a ventilation experiment for Mont Terri underground laboratory built in argillaceous rock formation. Our study starts with establishing a coupled thermo-hydro-mechano-chemical (THMC) processes model to simulate water transport in rock around the ventilated tunnel. Especially in this THMC formulation, a three-phase and two-constituent hydraulic model is introduced to simulate the processes which occur during tunnel ventilation, including desaturation/resaturation in the rock, phase change and air/rock interface, and to explore the Opalinus clay parameter set. It can be found that water content evolution is very sensitive to intrinsic permeability, relative permeability and capillary pressure in clay rock. Water loss from surrounding rock is sensitive to the change of permeability in clay which is induced by excavation damaged zone. Chemical solute transport in the rock near ventilation experiment tunnel is simulated based on the coupled THMC formulation. It can be estimated that chemical osmotic flow has little significance on water flow modeling. Comparisons between simulation results from 5 teams and experimental observations show good agreement. It increases the confidence in modeling and indicates that it is a good start for fully THMC understanding of the moisture transportation and mechanical behavior in argillaceous rock. 相似文献
916.
本文分别对城市创意产业内涵、类型及发展概况,以及废旧工业建造区的相关内涵及其发展概况进行了详细阐述,进而分析了二者之间存在的关系。最后以深圳“南海意库”等为例,探讨了城市创意产业发展与废旧工业建造区改造相结合在实践中的应用。 相似文献
917.
针对生活垃圾填埋场的主要恶臭污染物NH3、H2S、臭气浓度,以某城市生活垃圾填埋场为例,采用该填埋场自运行至今近10年的历史监测数据进行统计分析.结果表明,随着填埋年龄的增加,厂界处恶臭污染物浓度先增加后降低,在填埋场运行的第5~7年,恶臭污染物浓度达到最大值;通过监测数据和现场调查分析可知,该填埋场对周边800 m以外的村庄影响不明显. 相似文献
918.
对零件结构、毛坯结构、加工基准和工艺装备及切削用量的分析,是优化最佳的工艺路线的一般过程。本文主要对一般汽油机箱体的加工工艺,做些简要阐述和分析。 相似文献
919.
文中简要分析了395BI型电铲铲斗底板断裂、磨损的原因,着重讲述铲斗的组装及焊修工艺,概括说明修复后的395BI型电铲铲斗投入露天煤矿生产之后保持完好的近况,为此,395BI型电铲铲斗的成功修复,为以后此类大型焊接结构件的焊接维修提供可借鉴经验。 相似文献
920.
航空制造领域因轻量化、强度等特殊的应用需求,大量使用钛合金、镍基合金等难切削材料,刀具磨损速率快,刀具过度磨损会影响产品质量,在保证产品质量的前提下,为了充分发挥刀具使用价值,亟需监测刀具磨损状态和预测刀具剩余寿命。针对刀具剩余寿命预测的定义、分类和主要预测方法进行了阐述,同时,刀具磨损监测作为刀具寿命预测的基础和先决条件,简述了其重要的流程和常见模型。刀具剩余寿命预测模型主要包括基于物理模型的预测、基于数据驱动的预测和混合预测三大类,对不同预测方法的优缺点和适用场景进行总结,并讨论了刀具剩余寿命预测的未来研究方向。 相似文献