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The mechanical properties and failure behavior of single tire belts with different cord angles were investigated. The cords consisted of two pairs of twisted steel wires. Geometric moiré and the grid method were used to measure small and large deformations, respectively. The stress–strain curves of all samples tested display three typical deformation stages, initial nonlinear deformation, followed by an intermediate stage of approximately linear deformation and a final stage of approximately linear deformation with increased modulus. The transition strain from the first to the second stage increases linearly with cord angle and the ultimate strength is found to follow the Tsai–Hill failure criterion. Failure mechanisms varied with cord angle. They are classified into four modes including failure within the cord, shear failure at the interface between cord and rubber, a combination of the above two modes and cord breakage. In-plane shear properties were obtained using both the Arcan pure shear and the 22° off-axis tests. They were found to be in good agreement. A nonlinear micromechanics model was proposed to predict the properties of single belts with different cord orientations by taking into consideration both the material and geometric nonlinearities. 相似文献
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周边缝是面板坝十分关键的部位,受坝体变形及水压力的作用,将产生张开、沉降和错动三向位移.对高坝,因水头高,位移植更大,其止水的性能将直接影响坝体的运行.国内外已建工程大多采用表面塑性止水、中部PVC、底部铜片三道止水,近年来又在顶部铺填粉煤灰或粉细砂,以期在底部反滤的作用下,缝自动淤堵,起到辅助防渗的作用.但常这不到预期的效果,亦很难适应大变位的条件,对其逐步加以改进将是十分必要的.本文以几个工程实例及试验研究成果为例,对止水结构的型式进行了讨论. 相似文献
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Xiaoshuai Liu You Wu Xiaohao Xu Yuchao Li Yao Zhang Baojun Li 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(50)
The bidirectional transport of nanoparticles and biological cells is of great significance in efficient biological assays and precision cell screening, and can be achieved with optical conveyor belts in a noncontact and noninvasive manner. However, implantation of these belts into biological systems can present significant challenges owing to the incompatibility of the artificial materials. In this work, an optical conveyor belt assembled from natural biological cells is proposed. The diameter of the belt (500 nm) is smaller than the laser wavelength (980 nm) and, therefore, the evanescent wave stably traps the nanoparticles and cells on the belt surface. By adjusting the relative power of the lasers injected into the belt, the particles or cells can be bidirectionally transported along the bio‐conveyor belt. The experimental results are numerically interpreted and the transport velocities are investigated based on simulations. Further experiments show that the bio‐conveyor belt can also be assembled with mammalian cells and then applied to dynamic cell transport in vivo. The bio‐conveyor belt might provide a noninvasive and biocompatible tool for biomedical assays, drug delivery, and biological nanoarchitectonics. 相似文献
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输送带热硫化接头过程中常见问题及对策 总被引:1,自引:0,他引:1
钢丝绳芯输送带热硫化接头过程中常出现硫化面有气泡、局部粘接不好、跑胶、接口不顺直、接口裂缝等问题,从而降低了输送带的使用寿命,不但浪费了人力物力,而且也给正常生产造成一定的影响。通过采取预热下箱板、校验钢丝绳抽出力、校核接头长度、严格施工工艺等措施和方法,提高了胶带的胶接质量,保证了正常生产。 相似文献
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耗能减震层对框架-核心筒结构的减震效果及其影响分析 总被引:1,自引:0,他引:1
本文分析了加强层和3种不同耗能减震层对框架-核心筒结构的减震效果,以顶点位移为目标对单个粘滞耗能减震层的最佳布置位置进行了研究,并分析了粘滞环带耗能构件对结构性能的影响。分析结果表明,耗能减震层比加强层更能有效地控制结构的地震反应;单个耗能减震层宜布置在结构的中部0.5H~0.6H处;粘滞环带耗能构件能有效减小结构的位移和内力。 相似文献
39.
S. M. Pourmortazavi S. S. Hajimirsadeghi M. Rahimi-Nasrabadi I. Kohsari 《Chemical Engineering Communications》2013,200(10):1182-1188
A statistical experimental design method was implemented to optimize experimental conditions for the preparation of silver iodate fine belts using precipitation method. Ultrafine silver iodate belts were synthesized by addition of silver ion solution to the iodate reagent. The optimal conditions were determined using the Taguchi method. The effect of reaction conditions such as silver and iodate concentrations, flow rate of reagent addition, and temperature on the diameter of synthesized silver iodate belts were investigated. The results for analysis of variance (ANOVA) showed that silver iodate submicron belts can be synthesized by controlling silver concentration, flow rate, and temperature. Finally, the optimum conditions for synthesis of silver iodate submicron belts by this simple and fast method were proposed. The results of ANOVA showed that 0.001 mol/L silver ion concentration, 10 mL/min flow rate for addition of iodate reagent to the solution, and 0°C temperature are optimum conditions for producing silver iodate submicron belts with 228 ± 32 nm width. 相似文献
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