全文获取类型
收费全文 | 71篇 |
免费 | 3篇 |
专业分类
化学工业 | 15篇 |
轻工业 | 12篇 |
无线电 | 26篇 |
一般工业技术 | 7篇 |
冶金工业 | 6篇 |
原子能技术 | 1篇 |
自动化技术 | 7篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2012年 | 2篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 7篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 3篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有74条查询结果,搜索用时 15 毫秒
71.
Maria Atanassova 《溶剂提取与离子交换》2013,31(2):159-171
The solvent extraction of the lanthanide(III) ions (without Pm) with a 4‐benzoyl‐3‐phenyl‐5‐isoxazolone(HPBI) alone and in the presence of the quaternary ammonium salt Aliquat 336 in perchlorate form (QClO4) in C6H6 was investigated by the slope analysis method. The composition of the extracted species was determined as Ln(PBI)3 and Q[Ln(PBI)4] (Q+ is the quaternary ammonium salt cation). The values of the equilibrium constant were calculated. Synergistic effects were found for all lanthanide metals when they were extracted with a binary mixture of HPBI and QClO4. The influence of the synergistic agent on the extraction process has been discussed. The parameters of the extraction process were determined. The separation factors between adjacent metals were evaluated. 相似文献
72.
I. Mani?E. Atanassova N. Stojadinovi?D. Spassov A. Paskaleva 《Microelectronic Engineering》2011,88(3):305-313
The stress-induced leakage current in Hf-doped Ta2O5 layers (7; 10 nm) under constant voltage stress at gate injection was investigated in order to assess the mechanisms of conduction, the traps involved and the effect of Hf doping. The amount of Hf is found to affect the conduction mechanisms, the temperature dependence of the leakage current and the current response to the stress. A significant leakage current increase is observed only when the stress voltage and/or stress time exceed the corresponding threshold values, where the charge trapping at the pre-existing traps dominates below and defect generation above these threshold values. The energy levels of the traps responsible for the current transport are estimated. The stress effect on dominant conduction mechanisms appears quite weak, and the nature of the traps controlling the current transport before and after the stress seems to be nearly identical. The results indicate that the constant voltage stress affects the pre-existing traps in Hf-doped Ta2O5 and modifies their parameters, but there is no evidence for stress-induced generation of traps with completely new nature different from oxygen-vacancy related defects. 相似文献
73.
A conductive atomic force microscopy (C-AFM) has been used to study conductivity and electrical degradation of ultrathin (4 nm) Hf- and Al-doped Ta2O5 at the nanometer scale. The hardness testing has been also performed using the force measuring ability of the AFM. Since the size of the analyzed area is very small, features which are not visible by macroscopic tests are observed: extremely low leakage current (~ pA) up to significantly higher than the fields during standard current-voltage measurements; charge trapping/detrapping processes manifesting as current peaks at pre-breakdown voltages. Hf and Al addition improves the local conductivity of Ta2O5, provokes modification of the leakage current mechanism, and is effective in extending the potential of pure Ta2O5 as a high-k material at the nanoscale. The results point to a decisive role of the type of the dopant on the electrical and mechanical properties of the films and their local response to short term microwave irradiation. Hf-doped Ta2O5 exhibits excellent electrical stability and high hardness. Al doping provides more plastic films with large electrical inhomogeneities; the microwave treatment at room temperature is a way to improve these parameters to a level comparable to those of Hf-doped films. 相似文献
74.
The doping of Ta2O5 films with a proper element or its mixing with another high-k dielectric as a breakthrough to extend the potential of Ta2O5 toward meeting the criteria for future technological nodes is discussed. Essential issues in the engineering of storage capacitor parameters for dynamic memories based on Ti-doped Ta2O5, Hf-doped Ta2O5 and mixed HfO2–Ta2O5 layers are presented. The benefits and the disadvantages of these modified Ta2O5 stacks are discussed. 相似文献