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11.
Yu-Chun ChenPaul A. Kohl 《Microelectronic Engineering》2011,88(10):3087-3093
In this study, a technique is described to achieve enclosed air-cavities using a photosensitive sacrificial polymer with significantly lower residue. The residual residue after decomposition of the sacrificial polymer originates primarily from the photoacid generator used for patterning the polymer. In the two-layer technique, the photoacid is added only to the top layer resulting in significantly lower overall PAG loading. During decomposition, the photoacid used to decompose the polymer in the top layer then diffuses into the acid-free region promoting decomposition in the otherwise non-photosensitive layer. This approach significantly lowered the amount of residue produced. These results also showed that the acid generated from the PAG after UV radiation was not consumed by the polymer in the layer from which it originated. Rather, the acid was reused in other layers. The patterns fabricated from the two-layer structure used less PAG, had higher spatial resolution, and less line edge roughness. When the thickness of the top PAG-loaded layer was decreased, a lower UV exposure dose was required to achieve patterning. 相似文献
12.
《Optical Fiber Technology》2014,20(6):621-630
In this paper we present a review of holmium-doped silica fibre based sources. We discuss recent demonstrations of an efficient cladding-pumped fibre geometry and the impact it has made on the power scaling of these sources. We discuss the wavelength region that is addressable by holmium-doped silica based devices and highlight the advantage over thulium-doped fibres in terms of atmospheric transmission. Finally we review the development and current status of the pulsed and CW operation of holmium fibre sources and discuss the future development potential of sources in the ns-fs pulse-width range. 相似文献
13.
分散红3B在聚酯超细纤维上吸附等温线的绘制 总被引:1,自引:0,他引:1
对分散红3B上染普通聚酯纤维、减量前后聚酯超细纤维的等温吸附线进行了不测定,证实了在聚酯超细纤维的低温染色过程中存在Nernst和Langmuir二元吸附的可能性,并对其它位吸附的机理进进了分析。 相似文献
14.
Fibre-optic supertrunking has a well-established place in larger CATV networks. Supertrunks have to be transparent to the quality of the transmitted TV signals and they have to have a negligible impact on the system reliability of the total network. At least 60 dB (weighted) video SNR has to be achieved and down times of less than one hour per year per fibre are desirable. AM on fibre can achieve these goals only in shorter supertrunks. FM and digital modulation techniques with a higher loss budget than AM are well suited for high transmission quality as well as for redundant supertrunk topologies, achieving excellent system availability numbers at the expense of increased equipment complexity. 相似文献
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结合工程特点及工艺流程,阐述了300 kt/a聚丙烯装置的布置原则,管道、管架设计要点和方法,以及需要注意的问题。 相似文献
17.
阳极导电丝(CAF)是PCB业内近十年来较为热门的可靠性问题之一,当PCBA工作在高温高湿的环境下时,有可能产生沿玻璃纤维生长的阳极导电丝CAF。文章主要研究了PCB设计中的关键因素叠层设计对耐CAF性能的影响,通过分析不同半固化片的异同点,对比不同半固化片在玻纤裂纹和CAF失效寿命方面的差异。通过不同半固化片的CAF寿命数据,推算不同叠层设计的CAF寿命,为有较高cAF可靠性要求的产品研究提供了理论依据和试验基础。 相似文献
18.
R. Diaz de la Iglesia 《International Journal of Communication Systems》1992,5(4):225-235
This paper covers: (1) the field trials, with fibre in the local network systems, being conducted in Spain and intended for delivery telephone-based services to residential customers; (2) the technical and functional requirements of these types of system intended for commercial (regular) deployment to be started around late 1993/early 1994, and (3) the most relevant initial deployment scenarios and persubscriber investment aspects. The field trials are located in Madrid and in Barcelona: their rationale, technical characteristics and the lessons learned so far are described. Such trials are providing insight into what requirements and objectives are anticipated to be needed should such new technology be an actual alternative to copper-based subscriber loops. The requirement for such fibre in the local network systems intended for regular deployment in the near term are indicated, including technical and functional requirements of the optical line terminals (OLTs) (at local exchanges) and optical network units (ONUs) (located near customer premises); transmission requirements and optical distribution network (ODN) requirements and design aspects. For starting regular deployment, three preferred scenarios are identified. The chief parameters affecting persubscriber investments are illustrated including the number of fibres per ONU, and the number of users being served from each ONU. It is shown that in order to achieve cost parity with copper loop (which requires an initial investment of between $600 and $800) a capacity of some 60 narrowband (64 kb/s) channels per ONU should be required. 相似文献
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20.
双功能受阻胺与紫外线吸收剂并用的协同效应研究 总被引:10,自引:0,他引:10
本文用IR、UV、ESR、TLC等方法研究了新型的双功能受阻胺光稳定剂,Tinuvin-144 [2-(4′-羟基-3′,5′-二叔丁基)苄基-2-正丁基丙二酸五甲基哌啶醇酯]与紫外线吸收剂,UV-531(2-羟基-4-正辛氧基二苯甲酮)和UV-327(2-[2′-羟基-3′,5′-二叔丁基]-5-氯 代苯并三唑)并用体系对聚丙烯光稳定化的并用效应。结果表明,Tinuvin-144与UV-531,UV-327并用时均具有良好的协同效应,144对531,327或531,327对144的光分解均具有相互的保护作用。结果还表明,144与531或327无论在模拟体系或聚丙烯中,在诱导期内均不存在促使他们消耗的化学反应,提出了协同作用的机理。 相似文献