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41.
A logic scheme capable of performing AND-OR logic functions using charge-transfer devices is presented in this paper. Applications of the logic cell are discussed. A half-adder, a ‘flip-flop’, a majority logic gate, an analog-to-digital and a digital-to-analog converter are obtained by extending or modifying the basic scheme. An integrated MOS BBD realization of the AND-OR logic cell is described in detail. Experimental results are presented and shown to be in agreement with theoretical calculations. 相似文献
42.
Ngaiming Mok 《中国科学A辑(英文版)》2005,48(1):123-145
We study holomorphic immersions f:X →M from a complex manifoldX into a Kähler manifold of constant holomorphic sectional curvatureM, i.e. a complex hyperbolic space form, a complex Euclidean space form, or the complex projective space equipped with the Fubini-Study metric. ForX compact we show that the tangent sequence splits holomorphically if and only iff is a totally geodesic immersion. ForX not necessarily compact we relate an intrinsic cohomological invariantp(X) onX, viz. the invariant defined by Gunning measuring the obstruction to the existence of holomorphic projective connections, to an extrinsic cohomological invariant(f) measuring the obstruction to the holomorphic splitting of the tangent sequence. The two invariantsp(X) and?(f) are related by a linear map on cohomology groups induced by the second fundamental form. In some cases, especially whenX is a complex surface andM is of complex dimension 4, under the assumption thatX admits a holomorphic projective connection we obtain a sufficient condition for the holomorphic splitting of the tangent sequence in terms of the second fundamental form. 相似文献
43.
A logic array that performs both AND and OR functions using charge-transfer devices is proposed. Potential barriers are used to control the directionality of charge transfer and perform the logic functions. The basic operation of the devices is described and illustrated using 2-phase charge-coupled devices. 相似文献
44.
Arsenic and antimony in digested biological samples can be extracted with pyrrolidinecarbodithioate at pH 1 into chloroform and stripped with nitric acid for neutron-activation analysis (NAA). The extraction method eliminates interferences from matrix species, including Br and Na, making the accurate determination of low levels of As and Sb in biological materials feasible. The detection limits under the experimental conditions used are 0.005 and 0.006 mug/g for arsenic and antimony, respectively. A comparison of the results obtained for As and Sb in NBS biological standards by this method and by non-destructive instrumental neutron-activation analysis (INAA) is also given. 相似文献
45.
A novel gallium arsenide high-voltage MESFET structure (HVFET) suitable for high-voltage, high-speed output drivers is described. The device uses an extended drain region and a two-step gate field plate structure to achieve high breakdown voltage of 130 V. The device is implemented using a standard GaAs enhancement/depletion MESFET digital IC process without any additional processing steps and exhibits turn-on and turn-off times under 200 ps 相似文献
46.
Hojun Ryu Sein Kwon Sanghoon Cheon Seong Mok Cho Woo Seok Yang Chang Auck Choi 《ETRI Journal》2009,31(6):703-708
Silicon antimony films are studied as resistors for uncooled microbolometers. We present the fabrication of silicon films and their alloy films using sputtering and plasma‐enhanced chemical vapor deposition. The sputtered silicon antimony films show a low 1/f noise level compared to plasma‐enhanced chemical vapor deposition (PECVD)‐deposited amorphous silicon due to their very fine nanostructure. Material parameter K is controlled using the sputtering conditions to obtain a low 1/f noise. The calculation for specific detectivity assuming similar properties of silicon antimony and PECVD amorphous silicon shows that silicon antimony film demonstrates an outstanding value compared with PECVD Si film. 相似文献
47.
Polar oxide substrates for graphene growth: A first-principles investigation of graphene on MgO(111)
Kyung-Ah Min Jinwoo Park Junga Ryou Suklyun Hong Aloysius Soon 《Current Applied Physics》2013,13(5):803-807
Given the recent excitement over the truly two-dimensional carbon “super” material – graphene, there is now much effort and focus on the various possibilities of engineering the band gap of graphene for its device applications. One possible and promising route will be to grow graphene directly on some non-metallic substrates. In this paper, we address the atomic and electronic structure of various graphene structures on the polar MgO(111) using first-principles density-functional theory (DFT) calculations. We find that graphene generally interacts strongly with the O-terminated polar oxide surface, forming strong chemical bonds, inferred from both energetics and detailed density-of-states analysis. We compare our theoretical findings with available experimental results, offering a possible direction for future band gap engineering of graphene on such oxide substrates. 相似文献
48.
The process window for the infinite etch selectivity of silicon nitride (Si3N4) layers to ArF photoresist (PR) and ArF PR deformation were investigated in a CH2F2/H2/Ar dual-frequency superimposed capacitive coupled plasma (DFS-CCP) by varying the process parameters, such as the low frequency power (PLF), CH2F2 flow rate, and H2 flow rate. It was found that infinitely high etch selectivities of the Si3N4 layers to the the ArF PR on both the blanket and patterned wafers could be obtained for certain gas flow conditions. The H2 and CH2F2 flow rates were found to play a critical role in determining the process window for infinite Si3N4/ArF PR etch selectivity, due to the change in the degree of polymerization. The preferential chemical reaction of hydrogen with the carbon in the hydrofluorocarbon (CHxFy) layer and the nitrogen on the Si3N4 surface, leading to the formation of HCN etch by-products, results in a thinner steady-state hydrofluorocarbon layer and, in turn, in continuous Si3N4 etching, due to enhanced SiF4 formation, while the hydrofluorocarbon layer is deposited on the ArF photoresist surface. 相似文献
49.
Live morphological analysis of taxol-induced cytoplasmic vacuolization [corrected] in human lung adenocarcinoma cells 总被引:1,自引:0,他引:1
Taxol (paclitaxel), one of the most active cancer chemotherapeutic agents, can cause programmed cell death (PCD) and cytoplasmic vacuolization. The objective of this study was to analyze the morphological characteristics induced by taxol. Human lung adenocarcinoma (ASTC-a-1) cells were exposed to various concentration of taxol. CCK-8 was used to assay the cell viability. Atomic force microscopy (AFM), plasmid transfection and confocal fluorescence microscopy were performed to image the cells morphological change induced by taxol. Fluorescence resonance energy transfer (FRET) was used to monitor the caspase-3 activation in living cells during taxol-induced cell death. Cells treated with taxol exhibited significant swelling and cytoplasmic vacuolization which may be due to endoplasmic reticulum (ER) vacuolization. Caspase-3 was not activated during taxol-induced cytoplasmic vacuolization and cell death. These findings suggest that taxol induces caspase-3-independent cytoplasmic vacuolization, cell swelling and cell death through ER vacuolization. 相似文献
50.