全文获取类型
收费全文 | 15440篇 |
免费 | 1278篇 |
国内免费 | 899篇 |
专业分类
电工技术 | 948篇 |
技术理论 | 1篇 |
综合类 | 1079篇 |
化学工业 | 2440篇 |
金属工艺 | 782篇 |
机械仪表 | 950篇 |
建筑科学 | 1336篇 |
矿业工程 | 442篇 |
能源动力 | 487篇 |
轻工业 | 1169篇 |
水利工程 | 211篇 |
石油天然气 | 853篇 |
武器工业 | 119篇 |
无线电 | 1717篇 |
一般工业技术 | 1599篇 |
冶金工业 | 726篇 |
原子能技术 | 311篇 |
自动化技术 | 2447篇 |
出版年
2024年 | 92篇 |
2023年 | 288篇 |
2022年 | 471篇 |
2021年 | 629篇 |
2020年 | 502篇 |
2019年 | 401篇 |
2018年 | 449篇 |
2017年 | 507篇 |
2016年 | 428篇 |
2015年 | 621篇 |
2014年 | 753篇 |
2013年 | 857篇 |
2012年 | 917篇 |
2011年 | 1030篇 |
2010年 | 941篇 |
2009年 | 886篇 |
2008年 | 883篇 |
2007年 | 863篇 |
2006年 | 919篇 |
2005年 | 744篇 |
2004年 | 528篇 |
2003年 | 433篇 |
2002年 | 453篇 |
2001年 | 409篇 |
2000年 | 465篇 |
1999年 | 431篇 |
1998年 | 320篇 |
1997年 | 269篇 |
1996年 | 252篇 |
1995年 | 194篇 |
1994年 | 161篇 |
1993年 | 103篇 |
1992年 | 88篇 |
1991年 | 84篇 |
1990年 | 45篇 |
1989年 | 47篇 |
1988年 | 36篇 |
1987年 | 20篇 |
1986年 | 30篇 |
1985年 | 12篇 |
1984年 | 9篇 |
1983年 | 10篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1965年 | 1篇 |
1959年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Healing Effect of Controlled Anti‐Electromigration on Conventional and High‐Tc Superconducting Nanowires 下载免费PDF全文
Xavier D. A. Baumans Joseph Lombardo Jérémy Brisbois Gorky Shaw Vyacheslav S. Zharinov Ge He Heshan Yu Jie Yuan Beiyi Zhu Kui Jin Roman B. G. Kramer Joris Van de Vondel Alejandro V. Silhanek 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(26)
The electromigration process has the potential capability to move atoms one by one when properly controlled. It is therefore an appealing tool to tune the cross section of monoatomic compounds with ultimate resolution or, in the case of polyatomic compounds, to change the stoichiometry with the same atomic precision. As demonstrated here, a combination of electromigration and anti‐electromigration can be used to reversibly displace atoms with a high degree of control. This enables a fine adjustment of the superconducting properties of Al weak links, whereas in Nb the diffusion of atoms leads to a more irreversible process. In a superconductor with a complex unit cell (La2?x Cex CuO4), the electromigration process acts selectively on the oxygen atoms with no apparent modification of the structure. This allows to adjust the doping of this compound and switch from a superconducting to an insulating state in a nearly reversible fashion. In addition, the conditions needed to replace feedback controlled electromigration by a simpler technique of electropulsing are discussed. These findings have a direct practical application as a method to explore the dependence of the characteristic parameters on the exact oxygen content and pave the way for a reversible control of local properties of nanowires. 相似文献
92.
Silicon‐Sulfur Batteries: A Novel Lithiated Silicon–Sulfur Battery Exploiting an Optimized Solid‐Like Electrolyte to Enhance Safety and Cycle Life (Small 3/2017) 下载免费PDF全文
93.
Peng Chuanqi Gao Xiaofei Xu Jing Du Bujie Ning Xuhui Tang Shaoheng Bachoo Robert M. Yu Mengxiao Ge Woo-Ping Zheng Jie 《Nano Research》2017,10(4):1366-1376
A major clinical translational challenge in nanomedicine is the potential of toxicity associated with the uptake and long-term retention of non-degradable nanoparticles (NPs) in major organs.The development of inorganic NPs that undergo renal clearance could potentially resolve this significant biosafety concern.However,it remains unclear whether inorganic NPs that can be excreted by the kidneys remain capable of targeting tumors with poor permeability.Glioblastoma multiforme,the most malignant orthotopic brain tumor,presents a unique challenge for NP delivery because of the blood-brain barrier and robust blood-tumor barrier of reactive microglia and macroglia in the tumor microenvironment.Herein,we used an orthotopic murine glioma model to investigate the passive targeting of glutathione-coated gold nanoparticles (AuNPs) of 3 nm in diameter that undergo renal clearance and 18-nm AuNPs that fail to undergo renal clearance.Remarkably, we report that 3-nm AuNPs were able to target intracranial tumor tissues with higher efficiency (2.3x relative to surrounding non-tumor normal brain tissues) and greater specificity (3.0x)than did the larger AuNPs.Pharmacokinetics studies suggested that the higher glioma targeting ability of the 3-nm AuNPs may be attributed to the longer retention time in circulation.The total accumulation of the 3-nm AuNPs in major organs was significantly less (8.4x) than that of the 18-nm AuNPs.Microscopic imaging of blood vessels and renal-clearable AuNPs showed extravasation of NPs from the leaky blood-tumor barrier into the tumor interstitium.Taken together,our results suggest that the 3-nm AuNPs,characterized by enhanced permeability and retention,are able to target brain tumors and undergo renal clearance. 相似文献
94.
95.
Insight into In Situ Amphiphilic Functionalization of Few‐Layered Transition Metal Dichalcogenide Nanosheets 下载免费PDF全文
96.
97.
Liu Daobin Wu Chuanqiang Chen Shuangming Ding Shiqing Xie Yaofeng Wang Changda Wang Tao Haleem Yasir A. ur Rehman Zia Sang Yuan Liu Qin Zheng Xusheng Wang Yu Ge Binghui Xu Hangxun Song Li 《Nano Research》2018,11(4):2217-2228
Nano Research - Atomically dispersed catalysts have attracted attention in energy conversion applications because their efficiency and chemoselectivity for special catalysis are superior to those... 相似文献
98.
Han Wenjie Qin Xianying Wu Junxiong Li Qing Liu Ming Xia Yue Du Hongda Li Baohua Kang Feiyu 《Nano Research》2018,11(2):892-904
Nano Research - Porous Fe3O4/carbon microspheres (PFCMs) were successfully fabricated via a facile electrospray method and subsequent heat treatment, using ferrous acetylacetonate, carbon nanotubes... 相似文献
99.
一体化保障技术是目前提高复杂武器系统测试和保障能力的研究重点,为解决一体化保障技术中存在的指标冗余问题,结合粗糙集相关理论,提出了基于属性重要性和属性间影响度的约简算法;通过在某型一体化保障设备的柴油发电机子模块中应用该算法,在精简测试指标的同时,保证了较高的测试准确性,缩短了测试时间,验证并说明该理论可以有效地解决一体化保障技术中的指标冗余问题。 相似文献
100.