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81.
A coating consisting of (Cr2N−Mo2S3) overlay coating and an underlying Cr coating was deposited on a steel substrate by D.C. magnetron sputtering. The oxidation
characteristics of the deposited double-layered coating were studied at temperatures ranging from 400 to 900 °C in air. The
oxidation product was primarily Cr2O3. The unreacted coating beneath the oxide scale had some dissolved oxygen, sulfur, and iron. Oxidation of the coating occurred
via complex routes such as the outward diffusion of chromium and nitrogen from Cr2N and iron from the substrate, and the inward transport of oxygen from air, chromium from Cr2N, and S from Mo2S3. This counter diffusion of various ions occurred easily via fine crystallites that constituted the coating, which had some
solubility of S, O, and Fe. 相似文献
82.
在不同条件下用射频溅射方法制备了氮化碳薄膜。薄膜的电子结构和元素成分用傅里叶变换红外光谱(FTIR)和光电子能谱 (XPS)进行分析 ,薄膜的光学性质用紫外可见近红外光谱 (UV)进行检测。薄膜中的最大氮原子含量达到 0 .4 7,C1s和N1s电子的结合能产生了 2 .4 1~ - 1.7eV的移动 ,移动的大小取决于制备条件。UV谱表明氮化碳薄膜能强烈地吸收紫外光 ,而对红外光有较好的透明性 ,在 2 72 0nm附近存在一明锐的吸收峰 ,并给出了形成这一明锐吸收峰的适宜条件。这些结果对作为保护光学涂层的红外应用是有意义的。 相似文献
83.
在工作气压为0.80Pa的氧氩气混合气氛下,改变氧与氩的流量比(O2/Ar:0.10,0.20,0.30),在预先镀10nm左右SiO2的普通玻璃基片上用直流(D.C.)磁控溅射法制备了300nm左右的TiO2薄膜试样。离线在500℃、氧气氛下对试样热处理2h。用X射线光电子能谱(XPS)和X射线衍射仪(XRD)分别研究了试样热处理前后的表面元素组成、离子状态和物相组成,用接触角分析仪测试了试样在紫外光(UV)照射后的水润湿角。 相似文献
84.
85.
N. Fréty F. Bernard J. Nazon J. Sarradin J. C. Tedenac 《Journal of Phase Equilibria and Diffusion》2006,27(6):590-597
A study of copper (Cu) diffusion into silicon substrates through Ta nitride (TaN) and tantalum (Ta/TaN) layers was investigated
based on an experimental approach. TaN
x
and Ta/TaN
x
thin films were deposited by radiofrequency sputtering under argon (Ar) and Ar-nitrogen (N) plasma. The influence of the
N2 partial pressure on the microstructure and the electrical properties is reported. X-ray diffraction patterns showed that
the increase of the N2 partial pressure, from 2 to 10.7%, induces a change in the composition of the δTaN phase, from TaN to TaN1.13, as well as an evolution of the dominant crystallographic orientation. This composition change is related to a drastic increase
of the electrical resistivity over a N2 partial pressure of 7.3%. The efficiency of TaN layers and Ta/TaN multilayer diffusion barriers was investigated after annealing
at temperatures between 600 and 900 °C in vacuum. Secondary ion mass spectrometry profiles showed that Cu diffuses from the
surface layer through the TaN barrier from 600 °C. Cu diffusion mechanisms are modified in the presence of a Ta sublayer.
This article was presented at the Multicomponent-Multiphase Diffusion Symposium in Honor of Mysore A. Dayananda, which was
held during TMS 2006, the 135th Annual Meeting and Exhibition, March 12–16, 2006, in San Antonio, TX. The symposium was organized
by Yongho Sohn of the University of Central Florida, Carelyn E. Campbell of National Institute of Standards and Technology,
Richard D. Sisson, Jr., of Worcester Polytechnic Institute, and John E. Morral of Ohio State University. 相似文献
86.
在室温下,应用对靶直流磁控溅射设备在普通玻璃基片上制备了FePt(30nm)/Ti(tnm)颗粒膜样品,随后,在真空中进行了原位退火.详细研究了Ti衬底层对FePt颗粒膜的微结构和磁特性的影响.X射线衍射图谱表明样品形成了较有序的L10织构,Ti和FePt形成了三元FePtTi合金.当Ti层厚度t=5 nm、退火温度Ta=500℃时,样品具有高度有序的L10织构、小的颗粒尺寸和优异的磁特性.矫顽力超过了6.7 kOe,饱和磁化强度为620emu/cc.并且具有较小的开关场分布.结果表明FePt/Ti颗粒膜系统可作为超高密度磁记录介质的候选者. 相似文献
87.
GAO Haiyong ZHUANG Huizhao XUE Chengshan WANG Shuyun DONG Zhihua HE Jianting 《稀有金属(英文版)》2005,24(3):267-271
ZnO thin films were deposited on Si(111) substrates through a radio frequency (rf) magnetron sputtering system. Then the samples were annealed at different temperatures in air ambience and ammonia ambience respectively. The structure and composition of the ZnO films were studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The morphology of the samples was studied by scanning electron microscopy (SEM). Measured results show that ZnO films with hexagonal wurtzite structure were grown on Si(111) substrates when annealed in the two ambiences. The volatilization process of ZnO in the ammonia ambience at high temperature was discussed and the mechanism of the reaction was analyzed. 相似文献
88.
1 INTRODUCTIONOwingtolowdensityandhighspecificstrength ,aluminumanditsalloysareextensivelyusedinmanyfields ,especiallyinaviationandspaceindustry .Butlowhardnessandlowwearresistanceoftenlimittheirengineeringapplications .Surfacemodificationforalu minumanditsalloysbyionimplantationoffersthepossibilityofwideningtheirapplicationswherehighwearresistanceandlowdensityarerequired[15] .Sincenitrogenionisconvenienttoobtainandeasytocontrol,andAlNhasexcellentmechanicalproperties ,nitrogenionimplant… 相似文献
89.
氨化硅基Ga2O3/Al2O3制备GaN薄膜性质研究 总被引:1,自引:0,他引:1
研究了Ga2O3/Al2O3膜反应自组装制备GaN薄膜。首先利用磁控溅射法在硅衬底上制备Ga2O3/Al2O3膜,再将Ga2O3/Al2O3膜在高纯氨气气氛中氨化反应得到GaN薄膜。用傅里叶红外谱仪(FTIR),X射线衍射(XRD)和扫描电镜(SEM)对试样进行结构、组分和形貌分析。通过分析薄膜各方面的性质,得出了用此方法制备氮化镓薄膜的Al2O3缓冲层最佳的厚度为15nm左右,最佳氨化条件是在900℃下氨化15min。 相似文献
90.
本研究选择钽和铌的氮化物作为个体层材料,利用FJL560CI2型超高真空射频磁控与离子束联合溅射系统制备TaN、NbN及-系列的TaN/NbN多层薄膜.通过XRD和纳米力学测试系统以及摩擦磨损仪分析了该体系合成以后的晶体结构,以及调制周期对机械性能的影响.结果表明:多层膜的纳米硬度值普遍高于两种个体材料混合相的硬度值;当调制周期为8.5 nm时,TaN/NbN多层膜达到最大硬度30 GPa,结晶出现多元化,多层膜体系的硬度、应力、弹性模量以及膜-基结合性能均达到最佳效果. 相似文献