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991.
校园作为一个整体,如同城市一样有着它的特色、它的文化、它的故事,特别是历史悠久的老校园.本文通过对苏州大学王健法学院大楼中空间传承的分析,试图寻找建筑空间传承历史,传承文化的方法,从而对更多校园中新建筑的空间传承的营造进行探讨,乃至对整个城市中新建筑的空间传承进行研究. 相似文献
992.
多拓扑路由实现IP网络区分服务的优化算法* 总被引:2,自引:0,他引:2
在IP网络使用多拓扑技术对不同业务区分服务和路由优化的背景下,提出一种改进的链路权重优化启发式算法,在一定条件下以一定概率接受非可行解,从而引入松弛机制扩大候选解范围,避免搜索陷入局部最优。在仿真中将所提出的算法和已有算法进行了比较,结果证明该算法能够为每个高优先级需求的服务层协定(SLA)提供保证,有效降低全网总时延或提高网络吞吐量。 相似文献
993.
该文针对棉针织物前处理过程工艺指标吸水性和白度难以实现在线连续检测,且与前处理过程温度、时间、液碱浓度、双氧水浓度等影响因素具有较强非线性,难以建立精确数学模型。在分析了棉针织物前处理过程质量指标相关影响因素的基础上,采用最小二乘支持向量机建立了前处理过程工艺技术指标软测量模型,并通过实验验证了软测量模型的有效性。 相似文献
994.
讨论了两个自旋为h/2的电子的能级,本征波函数的求解及粒子处于z轴上的概率问题.通过两种不同的的方法得到了粒子处于z轴负方向上的概率,加深了对耦合表象下两个电子自旋性质的掌握,拓宽了量子力学的理论计算的思路. 相似文献
995.
New Algorithm for Binary Connected-Component Labeling Based on Run-Length Encoding and Union-Find Sets 总被引:1,自引:0,他引:1
Based on detailed analysis of advantages and disadvantages of the existing connected-component labeling (CCL) algorithm, a new algorithm for binary connected components labeling based on run-length encoding (RLE) and union-find sets has been put forward. The new algorithm uses RLE as the basic processing unit, converts the label merging of connected RLE into sets grouping in accordance with equivalence relation, and uses the union-find sets which is the realization method of sets grouping to solve the label merging of connected RLE. And the label merging procedure has been optimized: the union operation has been modified by adding the "weighted rule" to avoid getting a degenerated-tree, and the "path compression" has been adopted when implementing the find operation, then the time complexity of label merging is O(nα(n)). The experiments show that the new algorithm can label the connected components of any shapes very quickly and exactly, save more memory, and facilitate the subsequent image analysis. 相似文献
996.
Based on the steady-state strain measured by single-pass hot compression tests, the method by a double-pass hot compression
testing was developed to measure the metadynamic-recrystallization kinetics. The metadynamic recrystallization behavior of
low-alloy steel Q345B during hot compression deformation was investigated in the temperature range of 1 000–1 100 °C, the
strain rate range of 0.01–0.10 s−1 and the interpass time range of 0.5–50 s on a Gleeble-3500 thermo-simulation machine. The results show that metadynamic recrystallization
during the interpass time can be observed. As the deformation temperature and strain rate increase, softening caused by metadynamic
recrystallization is obvious. According to the data of thermo-simulation, the metadynamic recrystallization activation energy
is obtained to be Q
md=100.674 kJ/mol and metadynamic recrystallization kinetics model is set up. Finally, the error analysis of metadynamic recrystallization
kinetics model proves that the model has high accuracy (correlation coefficient R=0.988 6). 相似文献
997.
The hot compression test of 6063 Al alloy was performed on a Gleeble-1500 thermo-simulation machine, and the forming of 6063
rod extrudate in low-temperature high-speed extrusion was simulated with extrusion ratio of 25 on the platform of DEFORM 2D
successfully. From the compression experimental results, the flow stress model of this Al alloy is obtained which could be
the constitutive equation in the simulation of low-temperature high-speed extrusion process. From the numerical simulation
results, there is a higher strain concentration at the entrance of the die and the exit temperature reaches up to 522 °C in
low-temperature high-speed extrusion, which approaches to the quenching temperature of the 6063 Al alloy. The results show
that the low-temperature high-speed extrusion method as a promsing one can reduce energy consumption effectively. 相似文献
998.
Carbon spheres with size of 50–300 nm were synthesized via a solvent-thermal reaction with calcium carbide and chloroform
as reactants in a sealed autoclave. The morphologies and microstructures of carbon spheres before and after high temperature
treatment (HTT) were characterized by X-ray diffractometry (XRD), scanning electronic microscopy (SEM), energy diffraction
spectroscopy (EDS), and transmission electron microscopy (TEM). The formation mechanism of carbon spheres was discussed. The
results indicate that the carbon spheres convert to hollow polyhedron through HTT. Carbon spheres are composed of entangled
and curve graphitic layers with short range order similar to cotton structure, and carbon polyhedron with dimension of 50–250
nm and shell thickness of 15–30 nm. The change of solid spheres to hollow polyhedron with branches gives a new evidence for
formation mechanism of hollow carbon spheres. 相似文献
999.
Bi_2O_3-ZnO-B_2O_3 system glass is a kind of lead-free low melting sealing glasses. The structure of Bi_2O_3-ZnO-B_2O_3 system low-melting sealing glass was investigated by DSC, FT-IR, XRD and SEM. The results show that with the increase of B_2O_3 content, the transition temperature Tg and softening temperature T_f of Bi_2O_3-ZnO-B_2O_3 system low-melting sealing glasses increase, which leads to the liquid phase precipitation temperature increasing and promotes the structure stability in the glass. With increasing the heat treatment temperature, a large number of liquid phases appear in samples and the sinter efficiency of the samples increases. The FT-IR spectra of the glasses show the presence of some bands that are assigned to vibrations of Bi-O bond from [BO_3] pyramidal and [BiO_6] octahedral units and B-O from [BO_3] and [BO_4] units. With the decrease of B_2O_3 content, the crystallization tendency of the glass increases. In glass samples B_1 and B_2, crystallization starts at 460 ℃ and 540 ℃, respectively. Both of them precipitate Bi-(24)B_2O_(39) phases. 相似文献
1000.
跨文化传播是时尚品牌战略的重要方面.本文从跨文化传播设计的特点,时尚品牌广告文化的共通性和差异性,跨文化传播的基本原则和时尚品牌广告跨文化传播的策略等几个方面进行分析,旨在强调时尚品牌广告跨文化传播的信息整合与文化语境. 相似文献