全文获取类型
收费全文 | 2008050篇 |
免费 | 80825篇 |
国内免费 | 44440篇 |
专业分类
电工技术 | 77423篇 |
综合类 | 56258篇 |
化学工业 | 326372篇 |
金属工艺 | 97218篇 |
机械仪表 | 76064篇 |
建筑科学 | 81534篇 |
矿业工程 | 31602篇 |
能源动力 | 61629篇 |
轻工业 | 170568篇 |
水利工程 | 32184篇 |
石油天然气 | 53603篇 |
武器工业 | 7252篇 |
无线电 | 243664篇 |
一般工业技术 | 327733篇 |
冶金工业 | 211626篇 |
原子能技术 | 41392篇 |
自动化技术 | 237193篇 |
出版年
2022年 | 26937篇 |
2021年 | 38386篇 |
2020年 | 28287篇 |
2019年 | 25841篇 |
2018年 | 28863篇 |
2017年 | 29843篇 |
2016年 | 34217篇 |
2015年 | 37683篇 |
2014年 | 54334篇 |
2013年 | 118240篇 |
2012年 | 75333篇 |
2011年 | 90433篇 |
2010年 | 81980篇 |
2009年 | 88203篇 |
2008年 | 84652篇 |
2007年 | 80933篇 |
2006年 | 76891篇 |
2005年 | 65864篇 |
2004年 | 60573篇 |
2003年 | 54047篇 |
2002年 | 52087篇 |
2001年 | 48329篇 |
2000年 | 44587篇 |
1999年 | 39158篇 |
1998年 | 55573篇 |
1997年 | 45716篇 |
1996年 | 39474篇 |
1995年 | 33249篇 |
1994年 | 30776篇 |
1993年 | 30710篇 |
1992年 | 26874篇 |
1991年 | 23933篇 |
1990年 | 24234篇 |
1989年 | 23306篇 |
1988年 | 21739篇 |
1987年 | 19990篇 |
1986年 | 19313篇 |
1985年 | 22604篇 |
1984年 | 22552篇 |
1983年 | 20506篇 |
1982年 | 19481篇 |
1981年 | 19702篇 |
1980年 | 18329篇 |
1979年 | 18691篇 |
1978年 | 17911篇 |
1977年 | 18111篇 |
1976年 | 19784篇 |
1975年 | 16070篇 |
1974年 | 15543篇 |
1973年 | 15659篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Nienke Visser Harm Jan Lourens Gerwin Huls Edwin Bremer Valerie R. Wiersma 《International journal of molecular sciences》2021,22(5)
Elevated activation of the autophagy pathway is currently thought to be one of the survival mechanisms allowing therapy-resistant cancer cells to escape elimination, including for cytarabine (AraC)-resistant acute myeloid leukemia (AML) patients. Consequently, the use of autophagy inhibitors such as chloroquine (CQ) is being explored for the re-sensitization of AraC-resistant cells. In our study, no difference in the activity of the autophagy pathway was detected when comparing AraC-Res AML cell lines to parental AraC-sensitive AML cell lines. Furthermore, treatment with autophagy inhibitors CQ, 3-Methyladenine (3-MA), and bafilomycin A1 (BafA1) did not re-sensitize AraC-Res AML cell lines to AraC treatment. However, in parental AraC-sensitive AML cells, treatment with AraC did activate autophagy and, correspondingly, combination of AraC with autophagy inhibitors strongly reduced cell viability. Notably, the combination of these drugs also yielded the highest level of cell death in a panel of patient-derived AML samples even though not being additive. Furthermore, there was no difference in the cytotoxic effect of autophagy inhibition during AraC treatment in matched de novo and relapse samples with differential sensitivity to AraC. Thus, inhibition of autophagy may improve AraC efficacy in AML patients, but does not seem warranted for the treatment of AML patients that have relapsed with AraC-resistant disease. 相似文献
52.
人工智能的普及促进了语音交互技术的发展,语音传感器阵列作为智能语音交互的硬件前端,成为语音交互领域的前沿研究方向.矢量语音传声器自有的偶极子指向性、零点深度以及阵列体积小便于集成的特点特别符合语音交互技术对硬件设备的要求.基于此,通过采用两组矢量敏感单元"共点正交"形成矢量微阵列实现声源空间锐化波束指向,其不受瑞利限与空间采样率限制,与传统空间离散分布的声压麦克风阵列有着本质区别,是矢量微阵列的核心优势所在.矢量微阵列传声器弥补了现有双麦阵列的不足,具有更为广阔的应用前景,作为智能语音交互的硬件前端,对推动智能语音交互领域的发展具有重要意义. 相似文献
53.
To investigate the evolution of the structural and enhanced magnetic properties of GdMnO3 systems induced by the substitution of Mn with Cr, polycrystalline GdMn1-xCrxO3 samples were synthesized via solid-state reactions. XRD characterization shows that all GdMn1-xCrxO3 compounds with single-phase structures crystallize well and that Cr3+ ions entering the lattice sites of GdMnO3 induce structural distortion. SEM results indicate that the grain size of the synthesized samples (a few microns) decreases as the Cr substitution concentration increases. Positron annihilation lifetime spectroscopy reveals that vacancy-type defects occur in GdMn1-xCrxO3 ceramics and that the vacancy size and concentration clearly change with the Cr content. The temperature and field dependence of the magnetization curves show that Cr substitution significantly influences the magnetic ordering of the gadolinium sublattice, improving the weak ferromagnetic transition temperature and magnetization of GdMn1-xCrxO3. The enhanced magnetization of GdMn1-xCrxO3 is closely related to the vacancy defect concentration. 相似文献
54.
Wireless Personal Communications - Besides anti-malware usage for the eradication of malicious attacks, researchers have developed epidemic models in order to gain more insights into the spread... 相似文献
55.
Telecommunication Systems - Energy saving in User Equipment (UE) is one of the important issues for limited sources of power in the device. It is critical for the UE to maximize its energy... 相似文献
56.
Seredin P. V. Radam Ali Obaid Goloshchapov D. L. Len’shin A. S. Buylov N. S. Barkov K. A. Nesterov D. N. Mizerov A. M. Timoshnev S. N. Nikitina E. V. Arsentyev I. N. Sharafidinov Sh. Kukushkin S. A. Kasatkin I. A. 《Semiconductors》2022,56(4):253-258
Semiconductors - Abstract—In our work, we carry out a structural-spectroscopic study of AlGaN/GaN epitaxial layers grown by molecular-beam epitaxy with nitrogen-plasma activation on a hybrid... 相似文献
57.
Kravchenko V. F. Konovalov Ya. Yu. 《Journal of Communications Technology and Electronics》2022,67(8):952-964
Journal of Communications Technology and Electronics - A new design of wavelets based on the convolution of a compactly supported function with a rectangular pulse is proposed and theoretically... 相似文献
58.
Journal of Communications Technology and Electronics - A statistical study of the effectiveness of the non-threshold search procedure for a noise-like phase-shift keyed signal by the delay time is... 相似文献
59.
Boltar K. O. Burlakov I. D. Iakovleva N. I. Vlasov P. V. Lazarev P. S. 《Journal of Communications Technology and Electronics》2022,67(9):1175-1184
Journal of Communications Technology and Electronics - In recent years, there has been a rapid improvement in photonics products due to the use of multilayer heterostructures grown on the basis of... 相似文献
60.
Mobile Networks and Applications - Project MindCatcher is an art/research project which has the intention to explore the potential of interactive artistic environments for measuring and a better... 相似文献