全文获取类型
收费全文 | 9865篇 |
免费 | 916篇 |
国内免费 | 483篇 |
专业分类
电工技术 | 533篇 |
技术理论 | 1篇 |
综合类 | 730篇 |
化学工业 | 1614篇 |
金属工艺 | 678篇 |
机械仪表 | 669篇 |
建筑科学 | 670篇 |
矿业工程 | 305篇 |
能源动力 | 252篇 |
轻工业 | 714篇 |
水利工程 | 192篇 |
石油天然气 | 614篇 |
武器工业 | 94篇 |
无线电 | 1119篇 |
一般工业技术 | 1203篇 |
冶金工业 | 472篇 |
原子能技术 | 107篇 |
自动化技术 | 1297篇 |
出版年
2024年 | 44篇 |
2023年 | 206篇 |
2022年 | 327篇 |
2021年 | 464篇 |
2020年 | 340篇 |
2019年 | 281篇 |
2018年 | 328篇 |
2017年 | 396篇 |
2016年 | 273篇 |
2015年 | 422篇 |
2014年 | 549篇 |
2013年 | 607篇 |
2012年 | 714篇 |
2011年 | 663篇 |
2010年 | 672篇 |
2009年 | 596篇 |
2008年 | 541篇 |
2007年 | 545篇 |
2006年 | 574篇 |
2005年 | 447篇 |
2004年 | 314篇 |
2003年 | 263篇 |
2002年 | 267篇 |
2001年 | 220篇 |
2000年 | 191篇 |
1999年 | 197篇 |
1998年 | 164篇 |
1997年 | 128篇 |
1996年 | 104篇 |
1995年 | 89篇 |
1994年 | 84篇 |
1993年 | 48篇 |
1992年 | 54篇 |
1991年 | 39篇 |
1990年 | 23篇 |
1989年 | 15篇 |
1988年 | 19篇 |
1987年 | 9篇 |
1986年 | 18篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 11篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1978年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
83.
84.
Jin He Young Jin Jo Xianglang Sun Weiguo Qiao Jehyung Ok Tae-il Kim Zhong'an Li 《Advanced functional materials》2021,31(12):2008201
Squaraine dyes (SQs) are an important class of polymethine dyes with a unique reasonable-stabilized zwitterionic structure, in which electrons are highly delocalized over the conjugated bridge. These dyes can not only be easily synthesized via a condensation, but also exhibit intense absorption and emission in the visible and near-infrared region with excellent photochemical stability, making them attractive material candidates for many photoelectric and biomedical applications. Thus, in this review, after an introduction of SQs, the recent advances of SQs in the photovoltaic field are comprehensively summarized including dye-sensitized solar cells, organic solar cells, and perovskite solar cells. Then, the important advances in the use of SQs as the biosensors, biological imaging, and photodynamic/photothermal therapy reagents in the biomedical field are also discussed. Finally, a summary and outlook will be provided with some new perspectives for the future design of SQs. 相似文献
85.
Panithan Sriboriboon Huimin Qiao Seunghun Kang Changhyo Sun Yunseok Kim 《Advanced functional materials》2021,31(47):2103145
Ionically mediated phenomena underpin the functioning of various devices, including batteries, solid oxide fuel cells, memristors, and neuromorphic devices. The ionic behavior corresponding to ionically mediated phenomena causes not only variations in the electrical properties but also mechanical deformation, which is crucial for device reliability. However, the interrelation between ionically mediated electrical properties and mechanical deformation has not been elucidated yet. This study investigates ionically mediated mechanical deformation accompanied by memristive switching in a TiO2 single crystal through simultaneous conductive atomic force microscopy and electrochemical strain microscopy. A comprehensive analysis indicates the existence of a relationship between mechanical deformation and memristive switching based on the ionic behavior. Furthermore, an ionic state variable is used to simplify the interrelation between the electrochemical strain hysteresis and memristive switching associated with applied voltage. This study provides insights on the ionic behavior and can be extended to other systems for the general analysis of the relationship between mechanical deformation and electrical properties. 相似文献
86.
Tingting Wang Hao Zhang Hanghang Liu Qiang Yuan Feng Ren Yaobao Han Qiao Sun Zhen Li Mingyuan Gao 《Advanced functional materials》2020,30(3)
Fenton reaction–based chemodynamic therapy (CDT) has attracted considerable attention for tumor treatment, because the Fenton reaction can degrade endogenous H2O2 within the tumor to form reactive oxygen species (ROS) to kill cancer cells. The kinetics of the Fenton reaction has significantly influenced its treatment efficacy. It is crucial to enhance the reaction kinetics at the maximum H2O2 concentration to quickly produce vast amounts of ROS to achieve treatment efficacy, which to date, has not been realized. Herein, reported is an efficacious CDT treatment of breast cancer using biomimetic CS‐GOD@CM nanocatalysts, which are rationally designed to significantly boost the Fenton reaction through improvement of H2O2 concentration within tumors, and application of the second near‐infrared (NIR‐II) light irradiation at the maximum concentration, which is monitored by photoacoustic imaging. The biomimetic nanocatalysts are composed of ultra‐small Cu2?xSe (CS) nanoparticles, glucose oxidase (GOD), and tumor cell membrane (CM). The nanocatalysts can be retained in tumor for more than two days to oxidize glucose and produce an approximately 2.6‐fold increase in H2O2 to enhance the Fenton reaction under the NIR‐II irradiation. This work demonstrates for the first time the CDT treatment of cancer enhanced by the NIR‐II light. 相似文献
87.
In this paper, a hybrid intelligent method including fuzzy inference and neural network is presented for real-time self-reaction of a mobile robot in unknown environments. A neural network with fuzzy inference (fuzzy neural network, FNN) presented can effectively improve the learning speed of the neural network. The method can be used to control a mobile robot based on the present motion situations of the robot in real-time; these situations include the distances in different directions between the obstacles and the robot provided by ultrasonic sensors, the target orientation sensed by a simple optical range-finder and the movement direction of the robot. Simulation results showed that the above method can quickly map the fuzzy relationship between the inputs and the output of the control system of the mobile robot. 相似文献
88.
QIAO Hong-xia BU Fan-ge TAN Xia TONG Dian-min FAN Xi-jun 《光电子快报》2007,3(5):391-393
It is shown that in an open Λ-type system with spontaneously generated coherence, the transient evolution rule of the gain of lasing without inversion (LWI) is very sensitive to variation of the relative phase φ between the probe and driving fields; the variety of the atomic exit rateγ_0 and the ratio C of the atomic injection rates also have a considerable effect on the phase-dependent transient evolution rule of LWI gain. We find that whenφ=0, the transient and stationary LWI gain increases with C increasing but decreases with γ_0 increasing; whenφ≠0 , the effect of C andγ_0 on LWI gain is just opposite to that when φ=0 ; in order to get the largest transient and stationary LWI gain, we need selecting suitable values of φ,γ_0 and C. 相似文献
89.
All‐in‐One Theranostic Nanoplatform Based on Hollow TaOx for Chelator‐Free Labeling Imaging,Drug Delivery,and Synergistically Enhanced Radiotherapy 下载免费PDF全文
Guosheng Song Yu Chao Yuyan Chen Chao Liang Xuan Yi Guangbao Yang Kai Yang Liang Cheng Qiao Zhang Zhuang Liu 《Advanced functional materials》2016,26(45):8243-8254
Despite extensive use of radiotherapy in cancer treatment, there has been huge demand to improve its efficacy and accuracy in tumor destruction. To this end, nanoparticle‐based radiosensitizers, particularly those with high‐Z elements, have been explored to enhance radiotherapy. Meanwhile, imaging is an essential tool prior to the individual planning of precise radiotherapy. Here, hollow tantalum oxide (H‐TaOx) nanoshells are prepared using a one‐pot template‐free method and then modified with polyethylene glycol (PEG), yielding H‐TaOx‐PEG nanoshells for imaging‐guided synergistically enhanced radiotherapy. H‐TaOx‐PEG nanoshells show strong intrinsic binding with metal ions such as Fe3+ and 99mTc4+ upon simple mixing, enabling magnetic resonance imaging and single photon emission computed tomography imaging, respectively, which are able to track in vivo distribution of those nanoshells and locate the tumor. With mesoporous shells and large cavities, those H‐TaOx‐PEG nanoshells show efficient loading of 7‐ethyl‐10‐hydroxycamptothecin (SN‐38), a hydrophobic chemotherapeutic drug. By means of the radiosensitization effect of Ta to deposit X‐ray energy inside tumors, as well as SN‐38‐induced cell cycle arrest into radiation‐sensitive phases, H‐TaOx‐PEG@SN‐38 can offer remarkable synergistic therapeutic outcome in the combined chemoradiotherapy. Without appreciable systemic toxicity, such hollow‐TaOx nanostructure may therefore find promising applications in multimodal imaging and enhanced cancer radiotherapy. 相似文献
90.