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排序方式: 共有3130条查询结果,搜索用时 15 毫秒
1.
J. Hong E. S. Lambers C. R. Abernathy S. J. Pearton R. J. Shul W. S. Hobson 《Journal of Electronic Materials》1998,27(3):132-137
Dry etching of InGaP, AlInP, and AlGaP in inductively coupled plasmas (ICP) is reported as a function of plasma chemistry (BCl3 or Cl2, with additives of Ar, N2, or H2), source power, radio frequency chuck power, and pressure. Smooth anisotropic pattern transfer at peak etch rates of 1000–2000Å·min?1 is obtained at low DC self-biases (?100V dc) and pressures (2 mTorr). The etch mechanism is characterized by a trade-off between supplying sufficient active chloride species to the surface to produce a strong chemical enhancement of the etch rate, and the efficient removal of the chlorinated etch products before a thick selvedge layer is formed. Cl2 produces smooth surfaces over a wider range of conditions than does BCl3. 相似文献
2.
低压铝箔交流腐蚀研究 总被引:4,自引:2,他引:2
在30Hz频率下,通过铝箔在HCl+H2SO4+HNO3+H3PO4体系中的交流腐蚀,研究腐蚀液组成中腐蚀主体及缓蚀剂对铝箔腐蚀的作用,探讨腐蚀过程中电源频率、腐蚀液温度、电流密度及腐蚀时间对铝箔腐蚀的影响。腐蚀液组成的配比恰当,有利于比容的提高。在特定的频率下采用合适的腐蚀液温度、适宜的电流密度和腐蚀时间可以提高铝箔的静电容量。 相似文献
3.
4.
本文研究了采用锁定放大相干检测技术的等离子体光发射谱检测系统。用该系统检测了仅用CF4作为刻蚀气体刻蚀非晶硅基薄膜的等离子体光发射谱。分析了检测结果和刻蚀机理。 相似文献
5.
N‐(4‐Acetoxyphenyl) maleimide (APMI) and three kinds of comonomers bearing a trimethylsilyl group were copolymerized at 60°C in the presence of azobisisobutyronitrile (AIBN) as an initiator in 1,4‐dioxane to obtain the three IP, IIP, and IIIP copolymers. These copolymers were removed from the acetoxy group in a transesterification process into new IVP, VP, and VIP copolymers with a pendant hydroxyl group. Two modified processes were adopted to prepare photoresists using these copolymers. The first process involved mixing the dissolution inhibitor, o‐nitrobenzyl cholate, with the new copolymers. Second, o‐nitrobenzyl cholate was introduced into the copolymers using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in dimethylformamide (DMF). The cyclic maleimide structure is responsible for the high thermal stability of these copolymers. After irradiation using deep–UV light and development with aqueous Na2CO3 (0.01 wt %), the developed patterns showed positive images and exhibited good adhesion to the silicon wafer without using any adhesion promoter. The resolution of these resists was at least 0.8 μm and an oxygen‐plasma etching rate was 1/5.3 to that of hard‐baked HPR‐204. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2791–2798, 2002; DOI 10.1002/app.10255 相似文献
6.
7.
Jau-Jiun Chen Soohwan Jang F. Ren Yuanjie Li Hyun-Sik Kim D. P. Norton S. J. Pearton A. Osinsky S. N. G. Chu J. F. Weaver 《Journal of Electronic Materials》2006,35(4):516-519
Wet etch rates at 25°C for Zn0.9Mg0.1O grown on sapphire substrates by pulsed laser deposition (PLD) were in the range 300–1100 nm · min−1 with HCl/H2O (5×10−3−2×10−2 M) and 120–300 nm · min−1 with H3PO4/H2O (5×10−3−2×10−2 M). Both of these dilute mixtures exhibited diffusion-limited etching, with thermal activation energies of 2–3 kCal · mol−1. By sharp contrast, the etch rates for ZnO also grown on sapphire by PLD were much slower in similar solutions, with rates
of 1.2–50 nm · min−1 in HCl/H2O (0.01–1.2 M) and 12–54 nm · min−1 in H3PO4/H2O (0.02–0.15 M). The etching was reaction limited over the temperature range 25–75°C, with activation energies close to 6
kCal · mol−1. The resulting selectivity of Zn0.9Mg0.1O over ZnO can be a high as ∼400 with HCl and ∼30 with H3PO4. 相似文献
8.
M.A.R. Alves 《Microelectronics Journal》2005,36(1):51-54
We developed a process to obtain sharper silicon tips by employing anisotropic etching in a KOH solution followed by SF6 plasma etch. The tips were further sharpened using the established thermal oxidation technique to decrease the cone angle and, therefore, obtain smaller curvature radii. We have analyzed the impact of such changes in geometry on a figure of merit associated with the field emission characteristics. An increase in the figure of merit by a factor of three was found in relation to the tips before sharpening. 相似文献
9.
H.K. Kuiken 《Journal of Engineering Mathematics》2003,45(1):75-90
Asymptotic solutions are presented for diffusion-controlled wet-chemical etching through a round hole in a mask. The three-dimensional diffusion field is assumed to be axisymmetric and fully developed. Two time regimes are considered. The first applies when the etched depth is small in comparison with the width of the mask opening. In the second, the depth of etching is much greater than the width of the mask opening. Explicit solutions are found for the shape of the etched surface as a function of the physical parameters. Among other things it is found that, as long as the etched pits are shallow, etching through small apertures is faster than through larger ones. The opposite is true for deep pits. 相似文献
10.
Cu-Fe-Cr原位复合材料的纤维相结构 总被引:3,自引:0,他引:3
通过感应熔炼和冷拔变形制备了Cu 16Fe 2Cr原位复合材料 ,将铜基体选择腐蚀后提取出了纤维 ,采用SEM和TEM观察分析了纤维相结构。在较低的应变量 (η =1.6 7)时 ,纤维不均匀 ,随着变形量的增大 (η =5 .42 ) ,纤维外形变得均匀。在 η =5 .42时 ,一个显著的特点是单根Fe Cr纤维分为一些由晶界隔开的平行亚单元 (宽度约为 10 0nm) ,通过亚单元共同的 [110 ]衍射获得了晶粒之间的相对取向 ,相邻晶粒的取向角在 3°~ 15°之间。 相似文献