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排序方式: 共有574条查询结果,搜索用时 15 毫秒
61.
对热电池正极材料钒氧碳(VOC)的合成方法及性能特点作了评述。实验在不同工艺条件下的热反应制得不同成分的VOC材料,运用X射线衍射光谱法(XRD)和扫描电镜技术对所得产物进行了物相分析及形貌分析,并对其作为热电池正极材料的放电性能作了检测研究。实验结果表明:反应物配比、煅烧时间和温度对生成的VOC物相及性能都有重要的影响。粉末颗粒径向粒径小,比表面积较大的层片状及细棒状材料满足Li+快速扩散,使电池能够在较大电流密度下以较高的电压放电。对VOC材料进行放电性能测试发现,VOC能够提供较高的电压和平稳的放电平台,同时该化合物的重现性较好,容易加工成型,是一种较为理想的正极材料。 相似文献
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为了更迅速全面地将顾客需求转化为质量特性 ,提出了基于神经网络的动态 QFD方法 .该方法将神经网络与 QFD方法相结合 ,建立了 QFD神经网络模型 .通过网络的学习训练 ,获得最优的关系模型 .该方法能快速地将顾客需求变化传递给设计者 ,从而在第一时间内完成新产品的开发 .并以实例介绍了顾客需求模型以及顾客需求的获取方法 相似文献
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粉末涂料100%固体含量、零VOC,广泛应用于建筑铝型材、家用电器、管道防腐、钢筋防腐、金属家具等领域。在集装箱、汽车、卷材、家具、工程机械、船舶、钢结构这七大国家重点整治VOC排放领域,粉末涂料以其卓越的防腐与耐候特性,可实现真正的绿色涂装,其用量会大幅增长。但是在一些大型构件的现场施工中,粉末涂料涂装短期内难有用武之地。随着粉末涂料涂装技术的不断进步,粉末涂料将会有更多的应用空间。 相似文献
64.
This study quantifies emissions of hydrocarbon terpenes from the drying of sawdust in packed moving bed dryers, through the production chain to the finished pellets, and determines the parameters suitable for emission control. The terpene content in softwood sawdust and pellets was analyzed using gas chromatography. The distribution of VOC emissions over the bed was measured with a flame ionization detector. After drying, 30–40% of the initial terpenes remain in the wood, 20–30% remain after grinding, and 10–15% remain after pelleting. Dryer emissions correlate with residence time and final sawdust moisture content. Pellet press emissions correlate with pellet moisture content. 相似文献
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The Pennsylvania State University is researching an advanced oxidation system, which includes an air-phase photolytic chamber, an air/water stripping tower, and granular activated carbon (GAC) beds, for controlling volatile organic compounds (VOCs).A laboratory-scale experimental procedure has been employed that simulated certain aspects of several full-scale installations. The apparatus has been used to characterize the loading capacity and mass transfer zone of selected VOCs on coconut shell GAC. The GAC bed has then been placed in series with an ultraviolet reactor, which generates ozone and advanced oxidants in order to regenerate the loaded GAC at intensities of advanced oxidants that were higher than full-scale installations.VOC loading tests revealed that the adsorption of methyl isobutyl ketone (MIBK) was characterized by a well-defined mass transfer zone. Upon exposure to UV/O3, desorption and/or destruction of the MIBK and other VOCs occurred most prominently within the first inch of the GAC bed. This correlated with the penetration of advanced oxidants into the GAC bed, which also occurred most significantly in the bed's first inch. However, the amount of oxidant penetration increased with time. The removal of oxidants from air by GAC was accompanied by a decrease in mass of the GAC. The ability of oxidants to penetrate a GAC bed was altered when the bed was loaded with a VOC. 相似文献
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M. CastroAuthor Vitae B. KumarAuthor VitaeJ.F. FellerAuthor Vitae Z. HaddiAuthor VitaeA. AmariAuthor Vitae B. BouchikhiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,159(1):213-219
We report the original design of a new type of electronic nose (e-nose) consisting of only five sensors made of hierarchically structured conductive polymer nanocomposites (CPC). Each sensor benefits from both the exceptional electrical properties of carbon nanotubes (CNT) used to build the conductive architecture and the spray layer by layer (sLbL) assembly technique, which provides the transducers with a highly specific 3D surface structure. Excellent sensitivity and selectivity were obtained by optimizing the amount of CNT with five different polymer matrices: poly(caprolactone) (PCL), poly(lactic acid) (PLA), poly(carbonate) (PC), poly(methyl methacrylate) (PMMA) and a biobased polyester (BPR). The ability of the resulting e-nose to detect nine organic solvent vapours (isopropanol, tetrahydrofuran, dichloromethane, n-heptane, cyclohexane, methanol, ethanol, water and toluene), as well as biomarkers for lung cancer detection in breath analysis, has been demonstrated. Principal component analysis (PCA) proved to be an excellent pattern recognition tool to separate vapour clusters. 相似文献