全文获取类型
收费全文 | 61181篇 |
免费 | 5681篇 |
国内免费 | 3178篇 |
专业分类
电工技术 | 4361篇 |
技术理论 | 5篇 |
综合类 | 4255篇 |
化学工业 | 9536篇 |
金属工艺 | 3671篇 |
机械仪表 | 3554篇 |
建筑科学 | 5352篇 |
矿业工程 | 1608篇 |
能源动力 | 1813篇 |
轻工业 | 4021篇 |
水利工程 | 1103篇 |
石油天然气 | 3236篇 |
武器工业 | 514篇 |
无线电 | 7484篇 |
一般工业技术 | 7494篇 |
冶金工业 | 2613篇 |
原子能技术 | 783篇 |
自动化技术 | 8637篇 |
出版年
2024年 | 333篇 |
2023年 | 1142篇 |
2022年 | 1883篇 |
2021年 | 2721篇 |
2020年 | 1938篇 |
2019年 | 1605篇 |
2018年 | 1798篇 |
2017年 | 2008篇 |
2016年 | 1777篇 |
2015年 | 2413篇 |
2014年 | 2901篇 |
2013年 | 3589篇 |
2012年 | 3881篇 |
2011年 | 4110篇 |
2010年 | 3739篇 |
2009年 | 3430篇 |
2008年 | 3553篇 |
2007年 | 3384篇 |
2006年 | 3427篇 |
2005年 | 2870篇 |
2004年 | 2040篇 |
2003年 | 1851篇 |
2002年 | 1943篇 |
2001年 | 1713篇 |
2000年 | 1488篇 |
1999年 | 1593篇 |
1998年 | 1173篇 |
1997年 | 1038篇 |
1996年 | 1007篇 |
1995年 | 816篇 |
1994年 | 677篇 |
1993年 | 495篇 |
1992年 | 441篇 |
1991年 | 333篇 |
1990年 | 218篇 |
1989年 | 182篇 |
1988年 | 158篇 |
1987年 | 103篇 |
1986年 | 67篇 |
1985年 | 56篇 |
1984年 | 34篇 |
1983年 | 23篇 |
1982年 | 32篇 |
1981年 | 18篇 |
1980年 | 21篇 |
1979年 | 8篇 |
1978年 | 2篇 |
1959年 | 2篇 |
1951年 | 6篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
郑思孝 《核技术(英文版)》1994,(2)
ACOMPLEX-TYPEFOCUSSEDMAGNETRONFORSPUTTERING¥ZhengSixiao(郑思孝)(InstituteofNuclearScienceandTechnology,SichuanUniversity,Chengdu... 相似文献
82.
郑跃伟 《上海冶金高等专科学校学报》1995,(2)
由于水的选择性吸收特性,辐射换热中水份波长匹配一直是一个有分歧的问题。文章通过理论与计算论证了这个问题,得出的结论否定了波长匹配的重要性。 相似文献
83.
Zhongzhe Li Yufang Chen Xiaoru Yun Peng Gao Chunman Zheng Peitao Xiao 《Advanced functional materials》2023,33(32):2300502
Lithium metal batteries (LMBs), due to their ultra-high energy density, are attracting tremendous attentions. However, their commercial application is severely impeded by poor safety and unsatisfactory cycling stability, which are induced by lithium dendrites, side reactions, and inferior anodic stability. Electrolytes, as the indispensable and necessary components in lithium metal batteries, play a crucial role in regulating the electrochemical performance of LMBs. Recently, the fluorinated electrolytes are widely investigated in high-performance LMBs. Thus, the design strategies of fluorinated electrolytes are thoroughly summarized, including fluorinated salts, fluorinated solvents, and fluorinated additives in LMBs, and insights of the fluorinated components in suppressing lithium dendrites, improving anodic stability and cycling stability. Finally, an outlook with several design strategies and challenges will be proposed for novel fluorinated electrolytes. 相似文献
84.
Wang Lin Wang Xin Li Tao Zheng Ruijuan Zhu Junlong Zhang Mingchuan 《Neural computing & applications》2023,35(11):8051-8063
Neural Computing and Applications - Adaptive (sub)gradient methods have received wide applications such as the training of deep networks. The square-root regret bounds are achieved in convex... 相似文献
85.
Jine Zhang Xiaobing Chen Mengqin Wang Qinghua Zhang Wenxiao Shi Xiaozhi Zhan Meng Zhao Zhe Li Jie Zheng Hui Zhang Furong Han Huaiwen Yang Tao Zhu Banggui Liu Fengxia Hu Baogen Shen Yuansha Chen Yue Zhang Yunzhong Chen Weisheng Zhao Jirong Sun 《Advanced functional materials》2023,33(41):2306434
Ferromagnetic materials with a strong spin-orbit coupling (SOC) have attracted much attention in recent years because of their exotic properties and potential applications in energy-efficient spintronics. However, such materials are scarce in nature. Here, a proximity-induced paramagnetic to ferromagnetic transition for the heavy transition metal oxide CaRuO3 in (001)-(LaMnO3/CaRuO3) superlattices is reported. Anomalous Hall effect is observed in the temperature range up to 180 K. Maximal anomalous Hall conductivity and anomalous Hall angle are as large as ∼15 Ω−1 cm−1 and ∼0.93%, respectively, by one to two orders of magnitude larger than those of the typical 3d ferromagnetic oxides such as La0.67Sr0.33MnO3. Density functional theory calculations indicate the existence of avoid band crossings in the electronic band structure of the ferromagnetic CRO layer, which enhances Berry curvature thus strong anomalous Hall effects. Further evidences from polarized neutron reflectometry show that the CaRuO3 layers are in a fully ferromagnetic state (∼0.8 μB/Ru), in sharp contrast to the proximity-induced canted antiferromagnetic state in 5d oxides SrIrO3 and CaIrO3 (∼0.1 μB/Ir). More than that, the magnetic anisotropy of the (001)-(LaMnO3/CaRuO3) superlattices is eightfold symmetric, showing potential applications in the technology of multistate data storage. 相似文献
86.
Hu Zhigang Huang Yuhang Zheng Hao Zheng Meiguang Liu JianJun 《Pattern Analysis & Applications》2023,26(3):1481-1492
Pattern Analysis and Applications - The prosperity of datasets and model architectures has led to the development of pretrained source models, which simplified the learning process in multi-domain... 相似文献
87.
This paper is concerned with the heading tracking control problem for a network-based unmanned surface vessel (USV) under wave-induced disturbances. Considering the characteristics of the wave-induced disturbances, the unknown-but-bounded (UBB) noise model is adopted. Meanwhile, signal quantization is taken into account due to the limited capacity of the communication channel. Based on these considerations, a novel set-membership based control scheme is proposed, which consists of a set-membership filter (SMF) and a set-membership controller (SMC). In the proposed control scheme, the SMF is designed for providing an ellipsoidal estimation set for the USV at each sampling step, and then the SMC uses the estimation set for producing control input for the USV in order to track the reference. Sufficient conditions are derived for the considered USV system to be asymptotically stable and satisfy the modified set-membership performance constraint. Simulation results verifies the effectiveness of the proposed control scheme. 相似文献
88.
Wei Shang Guohao Jing Yulin Wang Tianlong Chen Zhou Liu Zhongzhong Zheng 《Asian journal of control》2023,25(4):2699-2719
The formation control for multiple quadrotors subject to maintaining the formation configuration and collision avoidance in the situation of stochastic links failure is investigated in this paper. First, the distributed formation controller is designed, the position controller is developed to manage the desired formation of position, and the attitude controller is developed to control the translation and rotation movements of the quadrotor. Then, in order to avoid the collisions between multiple quadrotors and the obstacles, a potential energy function method is introduced into the quadrotor formation control combined with the nest adaptive control. Inspired by the design of event trigger controller, a communication compensation controller is designed to ensure the stability of quadrotor formation under the condition of random communication interruption and recovery. Moreover, a prescribed time function is designed, which means the convergence time of the formation system can be set in advance. The prescribed time stability of the formation control system is proved by Lyapunov theory. Finally, the simulation results verify the effectiveness and superiority of this method. 相似文献
89.
Zheng Jianbing Gao Ming Lim Ee-Peng Lo David Jin Cheqing Zhou Aoying 《Knowledge and Information Systems》2022,64(7):1967-1996
Knowledge and Information Systems - Network robustness measures how well network structure is strong and healthy when it is under attack, such as vertices joining and leaving. It has been widely... 相似文献
90.
Xu Junwei Zheng Ruijuan Yang Lei Liu Muhua Song Jianqiang Zhang Mingchuan Wu Qingtao 《The Journal of supercomputing》2022,78(12):14504-14529
The Journal of Supercomputing - In the edge computing, service placement refers to the process of installing service platforms, databases, and configuration files corresponding to computing tasks... 相似文献