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排序方式: 共有730条查询结果,搜索用时 16 毫秒
61.
In this study, organic field-effect transistors (OFETs) with extended gate structure were fabricated for selective pH sensing applications. Indium tin oxide (ITO) was used as extended gate electrode as well as an active layer for H+ sensing. The threshold voltage of the fabricated ion-selective OFET was varied by the changes in the electrochemical potential at the ITO electrode surface upon its exposure to buffer solutions with variable pH values. The sensor showed excellent linearity and a high sensitivity of 57–59 mV/pH in the pH range of 2–12. The selectivity of the ITO sensing layer to H+ ions was also investigated by measuring the interfering effect of Ca2+ and K+ ions in the buffer pH solutions. The results showed that the Ca2+ and K+ ions weakly interfere with the selective pH sensing of the ITO-extended gate OFET sensor device. 相似文献
62.
Jin-A JeongHan-Ki Kim 《Thin solid films》2011,519(10):3276-3282
This study examined the characteristics of Ga:In2O3 (IGO) co-sputtered Zn:In2O3 (IZO) films prepared by dual target direct current (DC) magnetron sputtering at room temperature in a pure Ar atmosphere for transparent electrodes in IGZO-based TFTs. Electrical, optical, structural and surface properties of Ga and Zn co-doped In2O3 (IGZO) electrodes were investigated as a function of IGO and IZO target DC power during the co-sputtering process. Unlike semiconducting InGaZnO4 films, which were widely used as a channel layer in the oxide TFTs, the co-sputtered IGZO films showed a high transmittance (91.84%) and low resistivity (4.1 × 10− 4 Ω cm) at optimized DC power of the IGO and IZO targets, due to low atomic percent of Ga and Zn elements. Furthermore, the IGO co-sputtered IZO films showed a very smooth and featureless surface and an amorphous structure regardless of the IGO and IZO DC power due to the room temperature sputtering process. This indicates that co-sputtered IGZO films are a promising S/D electrode in the IGZO-based TFTs due to their low resistivity, high transmittance and same elements with channel InGaZnO4 layer. 相似文献
63.
Zijian YuanXiaming Zhu Xiong WangXikun Cai Bingpo ZhangDongjiang Qiu Huizhen Wu 《Thin solid films》2011,519(10):3254-3258
Considering practical applications in electronic devices, we studied the growth of In2O3 thin films on amorphous glasses by magnetron sputtering at room temperature and annealing effect on the structural and electrical properties. The vacuum annealed In2O3 thin films display a grain size enlargement and preferential orientation. Electrical characterization shows that the vacuum annealed In2O3 thin films exhibit a significant enhancement of both electron density and mobility, while air ambient annealing leads to a remarkable drop. The mechanism of the electrical characteristic changes in In2O3 thin films by annealing is explored by using different scattering mechanisms. Finally, a thin film transistor device using vacuum annealed In2O3 nano-meter thin films as active channel material is demonstrated. 相似文献
64.
A. Bouifoulen M. EdelyN. Errien A. Kassiba A. OutzourhitM. Makowska-Janusik N. GautierL. Lajaunie A. Oueriagli 《Thin solid films》2011,519(7):2141-2145
Nanocrystals of indium oxide (In2O3) with sizes below 10 nm were prepared in alumina matrixes by using a co-pulverization method. The used substrates such as borosilicate glasses or (100) silicon as well as the substrate temperatures during the deposition process were modified and their effects characterized on the structural and physical properties of alumina-In2O3 films. Complementary investigation methods including X-ray diffraction, optical transmittance in the range 250-1100 nm and transmission electron microscopy were used to analyze the nanostructured films. The crystalline order, morphology and optical responses were monitored as function of the deposition parameters and the post-synthesis annealing. The optimal conditions were found and allow realizing suitable nanostructured films with a major crystalline order of cubic phase for the In2O3 nanocrystals. The optical properties of the films were analyzed and the key parameters such as direct and indirect band gaps were evaluated as function of the synthesis conditions and the crystalline quality of the films. 相似文献
65.
用人工合成的硫化铟模拟实际硫化铟,研究了硫化铟在硫酸体系中常规浸出和以高锰酸钾、双氧水为氧化剂的氧化浸出的浸出效果和工艺条件。结果表明:在搅拌速度为800 r/min、物料粒度为75~96 μm、液固比为300∶1、温度为80 ℃、硫酸初始浓度为2.0 mol/L的条件下,常规浸出60 min,铟的浸出率为84.9%;而在相同条件下加入氧化剂KMnO4或H2O2进行氧化浸出,只需20 min就可使铟的浸出率达到94.9%或92.8%。在温度<70 ℃时,氧化剂的效应起主要作用,高锰酸钾的氧化效果比双氧水更明显;在温度>70 ℃时,温度效应占主导地位,两种氧化剂的影响差别不大。 相似文献
66.
To obtain highly conductive buried layers in InP:Fe, MeV energy Si, S, and Si/ Simplantations are performed at 200°C. The
silicon and sulfer implants gave 85 and 100 percent activation, respectively, for a fluence of 8 × 1014 cm−2. The Si/S co-implantation also gave almost 100 percent donor activation for a fluence of 8 × 1014 cm−2 of each species. An improved silicon donor activation is observed in the Si/S co-implanted material compared to the material
implanted with silicon alone. The peak carrier concentration achieved for the Si/S co-implant is 2 × 1019 cm3. The lattice damage on the surface side of the profile is effectively removed after rapid thermal annealing. Multiple-energy
silicon and sulfur implantations are performed to obtain thick and buried n+ layers needed for microwave devices and also hyper-abrupt profiles needed for varactor diodes. 相似文献
67.
S. Bollaert A. Cappy J.S. Galloo Z. Teukam J. Mateos B.G. Vasallo L. Berdnarz 《Thin solid films》2007,515(10):4321-4326
In this paper, we present a study on three-terminal ballistic junction and their applications to rectifiers and MUX/DEMUX. Rectifying effect is observed up to 94 GHz at room temperature. Although THz frequency performance has been demonstrated by Monte Carlo simulation, the high impedance of the nano-device combined with the parasitic capacitances is a limiting factor. 相似文献
68.
69.
Hongqiang Lu Malathi Thothathiri Ziming Wu Ishawara Bhat 《Journal of Electronic Materials》1997,26(3):281-284
Indium droplet formation during the epitaxial growth of InxGa1−xN films is a serious problem for achieving high quality films with high indium mole fraction. In this paper, we studied the
formation of indium droplets on the InxGa1−xN films grown by metalorganic chemical vapor deposition (MOCVD) using single crystal x-ray diffraction. It is found that the
indium (101) peak in the x-ray diffraction spectra can be utilized as a quantitative measure to determine the amounts of indium
droplets on the film. It is shown by monitoring the indium diffraction peak that the density of indium droplets increases
at lower growth temperature. To suppress these indium droplets, a modulation growth technique is used. Indium droplet formation
in the modulation growth is investigated and it is revealed in our study that the indium droplets problem has been partially
relieved by the modulation growth technique. 相似文献
70.
Alexander M. Samoylov Sergey A. Buchnev Nikolay N. Dementev Yury V. Synorov Vladimir P. Zlomanov 《Materials Science in Semiconductor Processing》2003,6(5-6):327-333
The chemical quantitative composition, phase constitution, and crystal structure of doped with In lead telluride films on Si (1 0 0) or SiO2/Si (1 0 0) substrates have been studied in this work. By EPMA and atomic absorption measurements, it has been found that the concentration of In atoms yIn varied from 0.0011 to 0.045 in these deposited Pb1−yInyTe films. The results of EPMA, SEM, and X-ray diffraction (XRD) measurements show that formation of In solid solutions in lead telluride matrix revealed not only in PbTe–InTe cross-section, but in PbTe–In2Te3 pseudobinary system also. The results of XRD show that the lattice parameter aPbTe of PbTeIn/Si and PbTeIn/SiO2/Si heterostructures is described by nonmonotone function and does not obey the Vegard's law within concentration interval 0.0011yIn0.045. 相似文献