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锁相检测式二维小角度测量装置 总被引:2,自引:1,他引:1
介绍了一种新型的二维小角度检测装置。由于该装置采用了光电自准直结构,以高灵敏度的四象限硅光电探测器作为检测元件,采用交流调制,锁相放大的方法对信号进行了处理,所以有效地消除了直流漂移的影响,提高了稳定性和测试精度。分析了光斑的形状和大小对测试结果的影响,研制了专门的标定装置。首先由高精度的光电自准直仪标定测量角度与输出信号的关系,并将相关数据存入单片机,然后由软件拟合出关系曲线。测量时,既可自动显示角度的大小,同时也可以与计算机相连。该测试系统结构小巧,具有较高的测量精度。 相似文献
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Jon Baker Krzysztof Wolinski Massimo Malagoli Don Kinghorn Pawel Wolinski Gábor Magyarfalvi Svein Saebo Tomasz Janowski Peter Pulay 《Journal of computational chemistry》2009,30(2):317-335
This article describes the capabilities and performance of the latest release (version 4.0) of the Parallel Quantum Solutions (PQS) ab initio program package. The program was first released in 1998 and evolved from the TEXAS program package developed by Pulay and coworkers in the late 1970s. PQS was designed from the start to run on Linux‐based clusters (which at the time were just becoming popular) with all major functionality being (a) fully parallel; and (b) capable of carrying out calculations on large—by ab initio standards—molecules, our initial aim being at least 100 atoms and 1000 basis functions with only modest memory requirements. With modern hardware and recent algorithmic developments, full accuracy, high‐level calculations (DFT, MP2, CI, and Coupled‐Cluster) can be performed on systems with up to several thousand basis functions on small (4‐32 node) Linux clusters. We have also developed a graphical user interface with a model builder, job input preparation, parallel job submission, and post‐job visualization and display. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 相似文献
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Luttmann E Ensign DL Vaidyanathan V Houston M Rimon N Øland J Jayachandran G Friedrichs M Pande VS 《Journal of computational chemistry》2009,30(2):268-274
Implementation of molecular dynamics (MD) calculations on novel architectures will vastly increase its power to calculate the physical properties of complex systems. Herein, we detail algorithmic advances developed to accelerate MD simulations on the Cell processor, a commodity processor found in PlayStation 3 (PS3). In particular, we discuss issues regarding memory access versus computation and the types of calculations which are best suited for streaming processors such as the Cell, focusing on implicit solvation models. We conclude with a comparison of improved performance on the PS3's Cell processor over more traditional processors. 相似文献
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Anna Evans Anja Bieberle-Hütter Henning Galinski Jennifer L. M. Rupp Thomas Ryll Barbara Scherrer René Tölke Ludwig J. Gauckler 《Monatshefte für Chemie / Chemical Monthly》2009,140(9):975-983
Abstract Micro-solid oxide fuel cells (micro-SOFC) are predicted to be of high energy density and are potential power sources for portable
electronic devices. A micro-SOFC system consists of a fuel cell comprising a positive electrode-electrolyte-negative electrode
(i.e. PEN) element, a gas-processing unit, and a thermal system where processing is based on micro-electro-mechanical-systems
fabrication techniques. A possible system approach is presented. The critical properties of the thin film materials used in
the PEN membrane are discussed, and the unsolved subtasks related to micro-SOFC membrane development are pointed out. Such
a micro-SOFC system approach seems feasible and offers a promising alternative to state-of-the-art batteries in portable electronics.
Graphical abstract Graphical Abstract text
相似文献
1000.
The ε-caprolactam was used to block the isocyanate group to enhance the storage stability of allyl (3-isocyanate-4-tolyl) carbamate. The spectra of FTIR and NMR showed that blocked allyl (3-isocyanate-4-tolyl) carbamate (BTAI) possesses two chemical functions, an 1-olefin double bond and a blocked isocyanate group. The FTIR spectrum showed BTAI could regenerate isocyanate group at elevated temperature. DSC and TG/DTA indicated the minimal dissociation temperature was about 135 °C and the maximal dissociation rate appeared at 226 °C. Then the styrene-b-(ethylene-co-1-butene)-b-styrene triblock copolymer (SEBS) was functionalized by BTAI via melt free radical grafting. The effect of temperature, monomer and initiator concentrations on the grafting degree and grafting efficiency was evaluated. The highest grafting degree was obtained at 200 °C. The grafting degree and grafting efficiency increased with the enhanced concentration of BTAI or initiator. The weight-average molecular weight (Mw) increased greatly at higher initiator concentration and lower ratio of the monomer/initiator. And the molecule weight distribution (MWD) of the modified SEBS became wider than that of pure SEBS. It is obvious that shearing thinning behavior of grafted SEBS is more profound than pure SEBS. 相似文献