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Fuxiao Chen Hejun Li Junqing Guo Yongshun Yang 《Materials Science and Engineering: A》2009,499(1-2):315-319
The superplastic properties of aluminum bronze were studied by way of artificial neural network. The model was established using Levenberg–Marquardt algorithm. It was improved by studying superplastic tension test data of aluminum bronze such that the superplastic forming parameters were optimized. According to the parameters, the experiment of superplastic extrusion of a solid bearing was performed. It is shown that the model reflected well the relationship between superplastic properties of aluminum bronze and superplastic tension conditions. The relative error between the test values and the predicted values of the network is less than 8.5%, which meets perfectly the demands of superplastic deformation of aluminum bronze. Moreover, the superplastic forming of solid cage of aluminum bronze show that it is feasible to produce solid cage using superplastic extrusion process. This extrusion process has remarkable economic benefits as well. 相似文献
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428XL仪器在可靠性、可操作性以及传输速度都得以提升的同时,其采集链由几段独立的电缆整合为一条整链,在野外检修采集链时,可能因为没有专用检测设备而无法按检修手册进行维修。本文讨论了WPSR和ST两种常用采集链在野外使用时,根据不同的地表条件有针对性采取的不同保护措施;并提出了适合于野外条件下进行采集链简易、快速维修的方法。 相似文献
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Leilei Zhang Feiyan Zhu Hejun Li Fei Zhao Shaoxian Li 《Ceramics International》2018,44(17):21229-21237
A duplex coating composed of electrophoretic deposited graphene oxide (GO) inner-layer and electrodeposited GO/Mg substituted hydroxyapatite (MH) outer-layer was prepared on carbon/carbon composites (CC). The morphology and microstructure of GO-GO/MH coating were researched by Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. The bonding strength between GO-GO/MH coating and CC substrate was investigated by shear test. The in-vitro bioactivity of GO-GO/MH coating was analyzed by simulated body fluid (SBF) immersion test. The results demonstrated that electrophoretic deposited GO inner-layer was successfully introduced on CC and could serve as an interlayer between CC and following electrodeposited GO/MH outer-layer. GO/MH outer-layer presented a flake morphology with 150–250?nm in thickness and 1.5–2.5?µm in width, exhibiting porous three-dimensional networks structure uniformly. The shear test showed that the bonding strength between the duplex coating and CC reached 7.4?MPa, which was 80.49% higher than that of single-layered MH coating without GO. The duplex coating could induce the formation of flocculent and chapped apatite after SBF immersion, which demonstrated the in-vitro bioactivity of the duplex coating. These results suggested that GO-GO/MH coating might be a promising candidate in the field of biomaterials, especially for implant coatings. 相似文献
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在2D碳/碳(C/C)复合材料的碳纤维与基体热解碳间引入中间相沥青做过渡层,研究了中间相沥青的引入对C/C复合材料力学性能的影响.结果表明,与没有过渡层,普通沥青做过渡层、中间相沥青做过渡层的三类C/C复合材料比较.采用沥青做过渡层可以提高复合材料的力学性能,采用中间相沥青做过渡层制备的C/C复合材料的弯曲强度比采用普通沥青做过渡层提高44%,剪切强度提高15%.中间相沥青的引入可以使碳纤维束间和束内的结合强度不同,从而使基体断裂产生的裂纹扩散时发生偏转,复合材料的强度和韧性同时得到提高. 相似文献
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神经网络预测液态挤压工艺参数的应用系统研究 总被引:1,自引:0,他引:1
文章通过对液态挤压新工艺的深入分析和研究,采用人工神经元网络方法建立了液态挤压工艺参数的预测模型,从而解决了用数学方法难以对液态挤压工艺建立精确模型的问题。同时,开发了一套基于神经网络,集建模、预测为一体的液态挤压工艺系统应用软件,为液态挤压工艺的实际应用和智能控制奠定了基础。 相似文献
49.
CVI制备碳/碳复合材料致密化行为模拟研究 总被引:2,自引:0,他引:2
化学气相渗透技术(CVI)是制备高性能碳/碳复合材料的一种重要方法,本文通过建立有限差分模型,对圆柱形单向碳/碳复合材料的CVI致密化行为进行了模拟,并详细描述、分析了模型原理与模拟步骤,设计了专门的对照实验,检验模型计算结果的准确性。对比结果表明,模拟值与实验结果具有很好的一致性,预测的渗透终止时间、终止密度与实验结果十分接近,误差在10%以下。 相似文献
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This paper presents a microfluidic system for separation of microparticles based on the use of dielectrophoretic barriers,
which are constructed by aligning two layers of microelectrode structure face-to-face on the top and bottom sides of the microchannel.
The energized barriers tend to prevent the particles in the flow from passing through. However, particles may penetrate the
barriers if a sufficiently high flow rate is used. The flow velocity at which the particles begin to penetrate the barrier
is defined as threshold velocity. Different particles are of different threshold velocities so that they can be separated.
In this paper, the electrodes are configured with open ends and aligned with a certain angle to the direction of the flow.
Polystyrene microbeads of different sizes (i.e., 9.6 and 16 μm in diameter) are studied in the tests. Under the experimental
conditions, two particle trajectories are observed: the 9.6 μm beads penetrate the barriers and move straightly toward the
fluidic outlet, while the 16 μm beads snake their way along the electrode edges at a relatively low speed. The two subpopulations
of particles are separated into spatial distance of ∼10 mm within tens of seconds. The system presents a rapid and dynamic
separation process within a continuous flow. 相似文献