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1.
为提高织物表面微滴喷射打印导电线路的成形质量,针对导电线路喷射打印过程中线路沉积形貌的起始端凸起现象,利用高速相机对线路成形过程进行采集,研究微滴间融合振荡过程中左右接触角的动态变化,微滴与线路融合以及液体向线路起始端的输送过程,提出线路起始端凸起的消除方案并进行实验。结果表明:在融合振荡过程中,微滴向起始端的振荡趋势始终大于向另一侧的振荡趋势,导致打印线路起始端的织物基板润湿区域不断扩大;微滴与线路接触后,其中一部分液体润湿织物基板拓展线路长度,一部分通过线路以恒定速度输送至起始端,在线路起始端形成凸起;利用抗坏血酸溶液润湿织物表面后,成形线路起始端凸起现象得到消除,整体线路路径均匀,沉积形貌良好。 相似文献
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In this study, we proposed a model for the morphological structure of electrospun membranes; it was different from the random distribution of fibers in a nonwoven. On the basis of our observation and analysis of the jet path by a high‐speed camera and the electrospun membranes by scanning electron microscopy, we proposed the base circle/deposition circle model of electrospun membranes. The base circle was used to position the deposition circles. The deposition circles, distributed on or around the base circle at a specific proportion, represented the distribution of the electrospun fibers on the collector. The pore characteristics and fiber distribution were compared between the electrospun membrane and simulated membranes with different spinning times; this verified that they had similar distribution trends. A membrane was simulated with a similar magnification ratio to the actual membrane. This further verified the model. This model could be used for the homogeneity simulation of an electrospun membrane in multinozzle electrospinning, and this may be helpful for predicting electrospun membranes in practical applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45653. 相似文献
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The fourth-order partial differential equations have good performance on noise smoothing and edge preservation without creating blocky effects on smooth regions. However, for low signal-to-noise ratio images, the discrimination between edges and noise is a challenging problem. A novel kernel-based fourth-order diffusion is proposed in this paper. It introduces a kernelized gradient operator in the fourth-order diffusion process, which leads to more effective noise removal capability. Experiment results show that this method outperforms several previous anisotropic diffusion methods for noise removal and edge preservation. 相似文献
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以环氧树脂为基体,短切玻璃纤维和玻璃纤维布为增强材料,通过RTM工艺制备了玻璃纤维增强环氧树脂(GF/EP)复合材料,并研究了RTM工艺制备玻璃纤维布增强环氧树脂(L-GF/EP)和短切玻璃纤维增强环氧树脂(S-GF/EP)复合材料的拉伸和弯曲性能,分析了开孔对两种复合材料拉伸性能的影响。结果表明:在拉伸过程中,开孔试样因孔边产生的应力集中,导致其拉伸强度与无孔试样相比下降了30%左右;玻纤铺层类型的不同对复合材料的力学性能具有显著影响;L-GF/EP复合材料内部结构完整,在载荷作用下,复合材料的弯曲断裂呈现一定的假塑性断裂模式,达到弯曲极限挠度值后,出现一定程度的回弹现象,其力学性能优于S-GF/EP复合材料。 相似文献
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Y. Cheng S.C. Lee J.C. Chow J.G. Watson P.K.K. Louie X. Hai 《The Science of the total environment》2010,408(7):1621-1627
PM2.5 (particle with an aerodynamic diameter less than 2.5 µm) was measured in different microenvironments of Hong Kong (including one urban tunnel, one Hong Kong/Mainland boundary roadside site, two urban roadside sites, and one urban ambient site) in 2003. The concentrations of organic carbon (OC), elemental carbon (EC), water-soluble ions, and up to 40 elements (Na to U) were determined. The average PM2.5 mass concentrations were 229 ± 90, 129 ± 95, 69 ± 12, 49 ± 18 µg m− 3 in the urban tunnel, cross boundary roadside, urban roadside, and urban ambient environments, respectively. Carbonaceous particles (sum of organic material [OM] and EC) were the dominant constituents, on average, accounting for ∼ 82% of PM2.5 emissions in the tunnel, ∼ 70% at the three roadside sites, and ∼ 48% at the ambient site, respectively. The OC/EC ratios were 0.6 ± 0.2 and 0.8 ± 0.1 at the tunnel and roadside sites, respectively, suggesting carbonaceous aerosols were mainly from vehicle exhausts. Higher OC/EC ratio (1.9 ± 0.7) occurred at the ambient site, indicating contributions from secondary organic aerosols. The PM2.5 emission factor for on-road diesel-fueled vehicles in the urban area of Hong Kong was 257 ± 31 mg veh− 1 km− 1, with a composition of ∼ 51% EC, ∼ 26% OC, and ∼ 9% SO4=. The other inorganic ions and elements made up ∼ 11% of the total PM2.5 emissions. OC composed the largest fraction (∼ 51%) in gasoline and liquid petroleum gas (LPG) emissions, followed by EC (∼ 19%). Diesel engines showed higher emission rates than did gasoline and LPG engines for most pollutants, except for V, Br, Sb, and Ba. 相似文献
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iSIGHT在鱼雷鳍舵优化设计中的应用研究 总被引:1,自引:0,他引:1
在解决鳍舵优化设计问题的过程中,引入集成优化框架iSIGHT,利用iSIGHT的优化迭代计算功能得到一种基于iSIGHT的鱼雷鳍舵优化设计方法,并将得到的设计方案与相同初值条件下通过传统方法得到的设计方案进行了分析和比较。分析比较的结果证明:用基于iSIGHT的优化设计方法来解决鱼雷鳍舵设计优化问题是可行的,并且能得到令人满意的设计方案。 相似文献
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