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951.
The goal of load balancing algorithm in OpenFlow networks is to combine the load balancing technology with the Open lqow technology, so that load balancing can adapt to the characteristics of the OpenFlow networks.The study of this paper focused on load balancing in OpenFlow networks, proposed a new load balancing algorithm.The algorithm considered the status of servers and network comprehensively, and provided the metrics for them.To distribute the network traffic to the servers and links reasonably, the goal of load balancing is reached. 相似文献
952.
刘林 《网络安全技术与应用》2014,(9):185-186
auhtorware是用来开发多媒体应用程序的设计软件.本文以一个院级获奖作品为例介绍了使用authorware开发一个多媒体课件的关键技术,如交互技术,外部程序调用技术,界面设计技术等. 相似文献
953.
The glass transition temperatures (Tg's) of several polystyrenes and styrene–alkyl methacrylate copolymers and terpolymers were measured using thermomechanical analysis (TMA) and differential scanning calorimetry (DSC). The polymers studied had number-average molecular weights from 3000 to 250,000 g/mole. The results indicate that the composition dependence of the Tg's for the copolymers and terpolymers can be satisfactorily described by a general Fox equation. In general, the measured Tg's of the copolymer and terpolymer samples depend more on the steric effects of the constituent pendent groups than on their molecular weights. The chain flexibility rather than the size of the pendent group is the determining factor in the glass transition properties of the styrene polymers. 相似文献
954.
Yinling Wang Yuan Hu Xinglong Gong Wanquan Jiang Peiqiang Zhang Zuyao Chen 《应用聚合物科学杂志》2007,103(5):3143-3149
Magnetorheological (MR) elastomers, which are mainly composed of magnetic particles and elastic polymer, are a new kind of smart materials whose modulus can be controlled by changing the strength of magnetic fields. In this article, MR elastomers based on immiscible silicon rubber/polystyrene (SR/PS) blend matrix were fabricated successfully via cosolvent method and the MR effect, electric and mechanical properties, and the microstructures of the corresponding materials were studied. SEM studies showed that the dispersion of iron particles in blend matrix were different from that in single polymer, which could be further proved by the different electric conductivity. The MR effect of MR elastomers based on blend matrix varied with the different ratios of SR and PS, which was discussed in detail from the special dispersion of iron particles and of zero‐modulus of MR elastomers. In addition, the MR elastomers based on SR/PS blend matrix had enhanced mechanical properties, which made them more hopeful to be applied in practice. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3143–3149, 2007 相似文献
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Summary: Poly(ethylene 2,6‐naphthalate) (PEN) can crystallize either from the glassy state or from the melt state. When crystallized from the glassy state, the sample was quenched from the melt in liquid nitrogen and then annealed at certain crystallization temperatures. When crystallized from the melt state, the sample was cooled to a preset temperature from the melt and then annealed for a certain time. The crystal modifications, morphologies and melting behaviors of PEN were investigated by means of wide‐angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), small‐angle light scattering (SALS) and differential scanning calorimetry (DSC). The results show that an α crystal modification of PEN was obtained when PEN crystallized from the glassy state, whilst a β crystal modification was obtained when PEN crystallized from the melt state at a higher temperature. An hedritic morphology of PEN crystal was obtained with only one melting peak observed in DSC curves when PEN was crystallized at a higher temperature from either the glassy state or the melt state. The α crystal modification could also be obtained when PEN was crystallized at a lower temperature from the melt. Spherulitic or banded spherulitic morphologies of PEN crystals, exhibiting multiple melting peaks in DSC curves, were observed when PEN was crystallized at a lower temperature. The multiple melting behaviors of PEN crystals may be associated with spherulitic structures composed of lamellae of varying thickness.
960.
为了研究抑制剂对银核和硫化银核的不同作用,本工作考察了1-苯基-5-巯基四氮唑(PMT)和苯并三氮唑(BTA)作为抑制剂在银核和硫化银核上物理显影的阳极抑制和解抑制效应。实验结果表明:1)PMT和BTA对Ag核和银离子过量时制得的硫化银核,Ag2S(Ag),的显影催化活性都有不同程度的抑制作用,而对硫离子过量时制得的硫化银核,Ag2S(S),无明显的抑制作用,这可能是由于过量硫离子在硫化银核上的吸附要强于这两种抑制剂;2)S2O3^2-或I^-离子的存在对BTA在Ag核上有解抑制作用,不仅可恢复甚至提高Ag核的显影催化活性,而对Ag2S核的抑制作用无明显影响;3)与BTA不同,S2O3^2-或I^-离子对PMT在Ag核上没有解抑制作用,对Ag2S(Ag)核的抑制作用还稍有增强,而对Ag2S(S)核稍有减弱;4)银溶胶中的表面增强拉曼谱(SERS)测量证实:BTA在Ag核上的吸附导致Ag核显影催化活性的下降,加入S2O3^2-或I^-离子后致使BTA的SERS信号消失则意味着BTA在银核表面的脱附。以上这些结果说明阳极抑制机理在抑制效应中有重要作用。 相似文献