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51.
A synergistic effect of high concentration of chloride and H2S on oxide formation and metal dissolution has been studied on 316L stainless steel by electrochemical measurements, inductive coupled plasma (ICP) and X-ray photoelectron spectroscopy (XPS). Chloride concentration had a significant effect on semiconductor properties of the oxide film, while the gases had little effect. A relatively high concentration of sulphur was found inside the oxide formed in a high chloride concentration electrolyte with high H2S compared to the oxide formed in low concentrations, which indicates that sulphur entered the oxide film through local weakening of the oxide by the chloride. 相似文献
52.
We have investigated the selective etching of 50 μm diameter via-holes for etch depth >200 μm using 30 μm thick photo resist mask in Inductively Coupled Plasma system with Cl2/BCl3 chemistry. Resultant etch rate/etch profiles are studied as a function of ICP process parameters and photo resist mask sidewall profile. Etch yield and aspect ratio variation with process pressure and substrate bias is also investigated at constant ICP power. The etch yield of ICP process increased with pressure due to reactant limited etch mechanism and reached a maximum of ∼19 for 200 μm depth at 50 mTorr pressure, 950 W coil power, 80 W substrate bias with an etch rate ∼4.9 μm/min. Final aspect ratio of etched holes is increased with pressure from 1.02 at 20 mTorr to 1.38 at 40 mTorr respectively for fixed etch time and then decreased to 1.24 at 50 mTorr pressure. The resultant final etch profile and undercut is found to have a strong dependence on the initial slope of photo resist mask sidewall angle and its selectivity in the pressure range of 20-50mTorr. 相似文献
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54.
文章将ICP刻蚀技术应用于刻蚀HgCdTe,使用微区X射线光电子光谱学(XPS) 、扫描电子显微镜( SEM)等表面分析技术研究了ICP各工艺参数,包括ICP功率、气体成分与配比、腔体压力等对刻蚀表面形貌、刻蚀后表面成分、聚合物形成的影响。XPS分析结果发现,使用光刻胶作掩模时,刻蚀气体CH4 会与光刻胶发生反应,生成物可能为C6H5 (CH3 ) 。如果腔体压力较高,生成物不能及时被带走,就会附着在样品表面上,使样品表面发黑;当腔体压力较低时,生成物被及时带走,则样品表面光亮,无聚合物残留。光刻胶也会与H2 发生反应,生成多种含C有机物。SiO2 作掩模时,在一定的条件下, CH4 会与SiO2 或者真空硅脂发生反应,生成聚脂薄膜。 相似文献
55.
Lu Yang 《Mass spectrometry reviews》2009,28(6):990-1011
For many decades the accurate and precise determination of isotope ratios has remained a very strong interest to many researchers due to its important applications in earth, environmental, biological, archeological, and medical sciences. Traditionally, thermal ionization mass spectrometry (TIMS) has been the technique of choice for achieving the highest accuracy and precision. However, recent developments in multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS) have brought a new dimension to this field. In addition to its simple and robust sample introduction, high sample throughput, and high mass resolution, the flat‐topped peaks generated by this technique provide for accurate and precise determination of isotope ratios with precision reaching 0.001%, comparable to that achieved with TIMS. These features, in combination with the ability of the ICP source to ionize nearly all elements in the periodic table, have resulted in an increased use of MC‐ICP‐MS for such measurements in various sample matrices. To determine accurate and precise isotope ratios with MC‐ICP‐MS, utmost care must be exercised during sample preparation, optimization of the instrument, and mass bias corrections. Unfortunately, there are inconsistencies and errors evident in many MC‐ICP‐MS publications, including errors in mass bias correction models. This review examines “state‐of‐the‐art” methodologies presented in the literature for achievement of precise and accurate determinations of isotope ratios by MC‐ICP‐MS. Some general rules for such accurate and precise measurements are suggested, and calculations of combined uncertainty of the data using a few common mass bias correction models are outlined. © 2009 Crown in the right of Canada. Published by Wiley Periodicals, Inc., Mass Spec Rev 28:990–1011, 2009 相似文献
56.
ICP—AES法测定钢铁中微量钙 总被引:1,自引:0,他引:1
用ICP—AES法测定钢铁中的钙不需经化学分离、富集,大大降低了空白值,方法简便、快速、灵敏度高,样品用酸溶解后直接测定,测定下限可达0.0005%。 相似文献
57.
通过微电子机械技术(MEMS)在抛光的熔融石英基材表面制作了平面精度达到0.4μm的超大单片面积的全息透镜。采用了分辨率达到0.2μm的步进投影式拼接光刻,适合石英基材的专用等离子耦合刻蚀(ICP)干法刻蚀技术,特殊的物理清洗方法,以及相关的多项辅助工艺。透镜理想面形横截面曲线为分段抛物线,每一片由23个柱状结构单元周期横向排列构成,采用等深度不等宽度的4台阶结构拟合,单元宽度约为2.966mm。在4in(10.16cm)圆片上,获得了单片尺寸为68mm×68mm的方形透镜。采用接触式台阶仪,扫描电子显微镜(SEM),高倍光学显微镜等方法进行不同阶段检测。结果显示:台阶平面精度为0.4μm,垂直精度为30nm,有非常好的立墙陡直度和刻蚀均匀性。此工艺方案可实现小规模批量生产,成本适中,可以直接用于制作6in(15.24cm)以上同等级要求的石英透镜,经适当改进也可用于蓝宝石等基底材料的制作。 相似文献
58.
以无水乙醇为溶剂、柠檬酸为分散剂,用超声分散技术配制Ni纳米粒子分散液;将分散液用旋涂的方法在GaN基发光二极管(LED)的ITO电流扩展层上制备单层Ni纳米粒子掩膜,采用ICP(inductively coupledplasma)干法刻蚀技术在ITO层上制作出表面粗化的结构。在20 mA工作电流下,与普通GaN基LED相比,这种ITO表面粗化的GaN基LED芯片发光强度提高了30%,并且对器件的电性能影响很小。结果表明,该表面粗化技术是一种工艺简单、成本低和能有效提高LED发光效率的方法。 相似文献
59.
随着各种混合信号电路的性能和集成度的迅速提高以及对电路模块和元器件小型化的需要,集成无源技术成为一种取代分立无源器件以达到小型化的解决方案。鉴于电容器被广泛用于滤波、调谐和电源回路退耦等各种板级集成封装中,采用Si MEMS工艺,在半导体表面深刻蚀三维(3D)图形以增大有效表面积,制作了一种高电容密度的半导体pn结退耦电容器,并分析研究了其主要制成工艺和性能。结果显示,所制作的电容器的电容密度达8~12nF/mm2,相比无表面三维刻蚀图形的半导体电容器电容密度增大了10倍以上,退耦频率范围为10kHz~3.2GHz,可用于中低频率较大范围内的退耦。 相似文献
60.