全文获取类型
收费全文 | 460篇 |
免费 | 10篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 12篇 |
综合类 | 2篇 |
化学工业 | 55篇 |
金属工艺 | 3篇 |
机械仪表 | 5篇 |
建筑科学 | 8篇 |
矿业工程 | 2篇 |
能源动力 | 11篇 |
轻工业 | 37篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
武器工业 | 1篇 |
无线电 | 90篇 |
一般工业技术 | 42篇 |
冶金工业 | 152篇 |
原子能技术 | 2篇 |
自动化技术 | 44篇 |
出版年
2021年 | 4篇 |
2019年 | 3篇 |
2017年 | 4篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 27篇 |
2012年 | 11篇 |
2011年 | 9篇 |
2010年 | 6篇 |
2009年 | 17篇 |
2008年 | 20篇 |
2007年 | 13篇 |
2006年 | 12篇 |
2005年 | 11篇 |
2004年 | 11篇 |
2003年 | 13篇 |
2002年 | 14篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 12篇 |
1998年 | 40篇 |
1997年 | 28篇 |
1996年 | 18篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 13篇 |
1992年 | 12篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1984年 | 6篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 3篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 7篇 |
1972年 | 3篇 |
1971年 | 7篇 |
1970年 | 3篇 |
1968年 | 2篇 |
1966年 | 2篇 |
1965年 | 2篇 |
排序方式: 共有471条查询结果,搜索用时 2 毫秒
81.
Martin A. Green Keith Emery David L. King Sanekazu Igari Wilhelm Warta 《Progress in Photovoltaics: Research and Applications》2005,13(1):49-54
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since June 2004 are reviewed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
82.
Martin A. Green Keith Emery David L. King Sanekazu Igari Wilhelm Warta 《Progress in Photovoltaics: Research and Applications》2005,13(5):387-392
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January, 2005 are reviewed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
83.
Tobin S.P. Vernon S.M. Bajgar C. Wojtczuk S. Melloch M.R. Keshavarzi A. Stellwag T.B. Venkatensan S. Lundstrom M. Emery K.A. 《Electron Devices, IEEE Transactions on》1990,37(2):469-477
A critical assessment of the photovoltaic quality of epitaxial GaAs grown by metal-organic chemical vapor deposition (MOCVD) and by molecular-beam epitaxy (MBE) is reported. Epitaxial films of nominally identical structure were grown by the two techniques and were fabricated into p-n heteroface solar cells. The 0.5-cm by 0.5-cm cells were then characterized and compared. The MOCVD-grown films produced independently verified record efficiency cells of 24.8% under 1-sun AM1.5 global conditions while the MB-grown films produced similarly high efficiencies of 23.8%. The material qualities of the two films in terms of minority-carrier diffusion lengths and surface recombination velocities were quite comparable. These results demonstrate that the quality of MBE-grown films can be quite comparable to the best MOCVD-grown films and that they are suitable for high-efficiency solar cells 相似文献
84.
Gunaëlle Levallet Fatmh Dubois Arthur Leclerc Edwige Petit Lien Bekaert Maxime Faisant Christian Creveuil Evelyne Emery Grard Zalcman Emmanule Lechapt-Zalcman 《International journal of molecular sciences》2022,23(11)
IDH (isocitrate dehydrogenase) mutation, hypoxia, and neo-angiogenesis, three hallmarks of diffuse gliomas, modulate the expression of small non-coding RNAs (miRNA). In this paper, we tested whether pro-angiogenic and/or pro-hypoxic miRNAs could be used to monitor patients with glioma. The miRNAs were extracted from tumoral surgical specimens embedded in the paraffin of 97 patients with diffuse gliomas and, for 7 patients, from a blood sample too. The expression of 10 pro-angiogenic and/or pro-hypoxic miRNAs was assayed by qRT-PCR and normalized to the miRNA expression of non-tumoral brain tissues. We confirmed in vitro that IDH in hypoxia (1% O2, 24 h) alters pro-angiogenic and/or pro-hypoxic miRNA expression in HBT-14 (U-87 MG) cells. Then, we reported that the expression of these miRNAs is (i) strongly affected in patients with glioma compared to that in a non-tumoral brain; (ii) correlated with the histology/grade of glioma according to the 2016 WHO classification; and (iii) predicts the overall and/or progression-free survival of patients with glioma in univariate but not in a multivariate analysis after adjusting for sex, age at diagnosis, and WHO classification. Finally, the expression of miRNAs was found to be the same between the plasma and glial tumor of the same patient. This study highlights a panel of seven pro-angiogenic and/or pro-hypoxic miRNAs as a potential tool for monitoring patients with glioma. 相似文献
85.
86.
87.
Emery Charles F.; Schein Rebecca L.; Hauck Emily R.; MacIntyre Neil R. 《Canadian Metallurgical Quarterly》1998,17(3):232
Exercise rehabilitation is recommended increasingly for patients with chronic obstructive pulmonary disease (COPD). This study examined the effect of exercise and education on 79 older adults (M age?=?66.6 ± 6.5 years; 53% female) with COPD, randomly assigned to 10 weeks of (a) exercise, education, and stress management (EXESM; n?=?29); (b) education and stress management (ESM; n?=?25); or (c) waiting list (WL; n?=?25). EXESM included 37 sessions of exercise, 16 educational lectures, and 10 weekly stress management classes. ESM included only the 16 lectures and 10 stress management classes. Before and after the intervention, assessments were conducted of physiological functioning (pulmonary function, exercise endurance), psychological well-being (depression, anxiety, quality of life), and cognitive functioning (attention, motor speed, mental efficiency, verbal processing). Repeated measures multivariate analysis of variance indicated that EXESM participants experienced changes not observed among ESM and WL participants, including improved endurance, reduced anxiety, and improved cognitive performance (verbal fluency). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
89.
OBJECTIVE: To determine whether HLA type is associated with career progress in rheumatology. DESIGN: Comparison of HLA type after HLA analysis of samples of venous blood. SETTING: Department of Rheumatology Research, University of Birmingham. SUBJECTS: All (37) staff in the department. RESULTS: All the senior academics and most staff with a PhD expressed HLA-DR4. The prevalence of expression in each of these groups was significantly greater than that found in the controls. None of the junior doctors or secretaries expressed DR4. CONCLUSION: The junior doctors in the department have poor career prospects as HLA-DR4 seems to be associated with academic achievement. 相似文献
90.