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51.
抽气热电偶隔热罩黑度变化下陶瓷窑高温烟气测温误差分析 总被引:1,自引:1,他引:0
为了研究隔热罩黑度变化下抽气热电偶的测试误差,根据陶瓷窑内高温烟气静态和动态不同情况,对抽气热电偶测试误差进行推导与计算,结果显示,由于隔热罩黑度变化,高温烟气抽气热电偶测试误差较大,必须对输出信号进行修正。 相似文献
52.
聂保生 《稀有金属与硬质合金》1997,(2):15-17
通过试验,对比分析了改进工艺对碲品位及直收率的影响。结果表明,在浸出、除杂过程中加入CaCl2溶液,可显著提高碲的品位和直收率. 相似文献
53.
报道了对一系列不同组份的ZnSxTe1-x(0≤x〈1)混晶的喇曼菜射和光致姚研究,室温下的喇曼散实验结果表明ZnSxTe1-x中的声子具有双模行为,研究了ZnSxTe1-x混晶的反射谱,背散射和边发射配置下的光致发光谱,以及10~300K温度范围内光至发光谱的温度关系,结果表明:x较小时,ZnSxTe1-x的发光来源于混晶带边发光或浅杂质的发光,x接近1时,发光蜂来源于束缚在Te等电子自陷激子的 相似文献
54.
F. C. Peiris M. R. Buckley O. Maksimov M. Munoz M. C. Tamargo 《Journal of Electronic Materials》2003,32(7):742-746
We have used a combination of prism-coupling, reflectivity, and ellipsometric techniques to investigate the indices of refraction,
n, of a series of BexZn1−xTe thin films grown on InP substrates. After determining the concentrations of each of the BexZn1−xTe alloys using x-ray diffraction measurements, we measured their n at discrete wavelengths using a prism-coupler setup. In
addition, we used reflectivity measurements to complement the prism-coupler data and arrive at the dispersion relations of
n for the BexZn1−xTe alloys below their fundamental energy gaps. We then employed a rotating analyzer-spectroscopic ellipsometer to measure
the complex reflection ratio for each of the films at angles of incidence of 65°, 70°, and 75°. By using the n values obtained
from both the prism-coupler and the reflection-spectroscopy techniques to guide the ellipsometric analysis, we were able to
obtain accurate results for the dispersion of n for the BexZn1−xTe alloys, not only below their fundamental energy gaps, but also above their energy gaps (up to 6.5 eV) using these three
complementary techniques. 相似文献
55.
A comparative study and performance characteristics of ion-implanted and heterojunction short-wave infrared HgCdTe focal-plane arrays 总被引:2,自引:0,他引:2
S. Terterian M. Chu S. Mesropian H. K. Gurgenian M. Ngo C. C. Wang 《Journal of Electronic Materials》2002,31(7):720-725
Short-wave infrared (SWIR) HgCdTe focal-plane arrays (FPAs) with a cutoff wavelength of 2.5 μm have been produced using both
planar ion-implanted and heterojunction-mesa device structures. The two-dimesnional FPAs are comprised of a 320×256 format
with 30-μm pixel pitch and are cooled by a multistage thermo-electric (TE) cooler. Measured R0A values of the two types of device structures show similar results below about 130 K because of the performance-limiting
effect of the surface passivation of the heterojunction. However, a substantial difference is seen above 130 K and up to 300
K between the two structures types, with the heterojunction-mesa p-on-n device having an order of magnitude higher R0A value than the planar ion-implanted n-on-p configuration. The difference in the R0A values is reflected in the FPA images of the two different device types, where at 200 K, both FPAs display a clear picture
with the n-on-p implanted device having a somewhat lesser resolution. However, no image can be seen from the planar-implanted
FPA at 300 K, whereas the heterojunction-mesa FPA still exhibits a notable image at this temperature. These differences are
examined and are attributed largely to higher diffusion and generation-recombination (g-r) currents that are thought to be
prevalent in the ion-implanted n-on-p device structure. Yet, baking studies carried out show the ion-implanted diodes to be
slightly more robust, as experiments reveal that they tend to survive a 120°C heat treatment longer than the mesa devices,
which tend to degrade after a certain period of time. The nature of n-type donors in ion-implanted diodes is discussed, and
a new theory based on Te antisites is proposed to explain recent experimental findings. 相似文献
56.
Zoran Djuric Zoran Djinovic Zarko Lazic Jozef Piotrowski 《Journal of Electronic Materials》1988,17(3):223-228
A quantitative model of isothermal vapor phase epitaxy is proposed. It can be applied to both closed and open tube systems.
This model enables the prediction of compositional profiles of the layers grown by isothermal vapor phase epitaxy with dependence
on the growth parameters and thermodynamical data of the (Hg,Cd)Te system. The dependence of compositional profiles of the
ISOVPE layers on temperature and time of deposition, source to substrate spacing, mercury and inert gas pressures are discussed
for both solid and liquid sources. Modification of the compositional profiles by the postgrowth annealing has also been studied.
The proper choice of growth and annealing parameters makes the optimization of the profiles possible. The calculated profiles
are compared with the experimental data and a satisfactory quantitative fit is found in most cases. The possible reasons for
remaining discrepancies are discussed. 相似文献
57.
铸铁炉前热分析存在问题及解决途径 总被引:1,自引:0,他引:1
针对工厂中利用分析法炉前测试铁水成分误差较大的主要原因进行了较全面的分析,并在测试装置、铁水质量、数学模型上提出了相应的解决途径。 相似文献
58.
Large single crystals of Pb1-xGexTe (0 < × < 0.105) up to 10 g and Pb1-ySnyTe (0 < y < 0.26) up to 125 g were grown in sealed
tubes by self-transport onto oriented single crystal seeds. The crystals were free of voids and inclusions, had dislocation
densities as low as 103 cm-2, and were uniform in composition. Pertinent details of the growth technique, including thermal
conditions, stoichiometry of the source, and seed orientation, are described. Results of evaluation of the crystals by metallography,
Laue X-ray topography, and electron microprobe analysis are presented. 相似文献
59.
从电化学角度研究了Ge2Sb2Te5薄膜在化学机械抛光液中的作用,以及不同的pH值和H2O2浓度下的电化学特性. 采用Solartron SI1287电化学设备测试了Ge2Sb2Te5薄膜在溶液中的开路电位和动电位扫描. 开路电位结果表明:Ge2Sb2Te5在pH值为10的抛光液中表现出钝化行为;而抛光液的pH值为11时,开始向活化转变;当pH值为12时,薄膜处于活化状态. 在动电位扫描过程中,不同的pH值和H2O2浓度下,薄膜的扫描曲线形状相似,表明薄膜腐蚀具有相同的反应机理. 自制碱性抛光液,对Ge2Sb2Te5薄膜进行化学机械抛光,用SEM和EDS对抛光后的结构进行分析. 结果表明,通过CMP实现了Ge2Sb2Te5填充结构. 相似文献
60.
A novel set-up for horizontal open-tube vapor transport epitaxy of Hg1−xCdxTe films is described. Mirror-like Hg1−xCdxTe epitaxial layers with thicknesses up to 40 Μm were grown and characterized. The growth temperature ranged from 380 to 550‡C,
with growth rates of the order of 0.5–7 Μm per hour. The concentration depth profiles and the optical and electrical properties
of relatively uniform films with x≈0.3–0.4 are reported. The process kinetics are studied. A simple model which takes into
account the reactions occurring at the boundaries of the epitaxial layer and the interdiffusion in the epilayer is presented
and discussed. The model fits the experimentally observed characteristics of the epitaxial growth process. A constant growth
rate leading to a linear dependence of film thickness upon deposition time y–yi=ks t is derived. The reaction rate constant k is given by ks=koe−Ea/kT with ko=0.18 cm-sec−1and the energy of activation Ea=1.12 eV. 相似文献