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991.
Quartz Resonators for Monitoring Thin-Film Mass and Thickness 总被引:1,自引:0,他引:1
A detailed analysis is presented for a quartz resonator-film system that substantially improves the accuracy in determining the mass and thickness. A proposed method of measuring the mass and other physical properties of the films is tested by experiment, which does not require preliminary calibration.__________Translated from Izmeritelnaya Tekhnika, No. 2, pp. 29–32, February, 2005. 相似文献
992.
Kobayashi S Okamoto K Maesato K Moriya H Ohtake T 《Hemodialysis international. International Symposium on Home Hemodialysis》2005,9(3):268-274
Concerning a role of blood rheology for atherosclerosis in patients with hemodialysis (HD), little data are available. It may be due to the fact that the method for evaluating rheologic properties of circulating blood has been limited. We examined blood rheology in 118 HD patients by using microchannel array flow analyzer that makes it possible to directly observe the flow of blood cell elements through the microchannel. Transit time (T(B)) of heparinized whole blood through slit pores (7 x 30 microm) was used as an index of rheology and related with various inflammatory biomarkers such as high-sensitive CRP (hsCRP), monocyte chemotactic protein-1, osteopontin, or fibrinogen (Fg). Moreover, as a surrogate marker of atherosclerosis, carotid intima-media thickness (IMT) and aortic stiffness evaluated by brachial-ankle pulse-wave velocity (baPWV) were studied. In HD patients, T(B) had strong positive correlations with hsCRP (r = 0.427; p < 0.00001), Fg (r = 0.452; p < 0.00001), and osteopontin (r = 0.227; p < 0.0134). Further, T(B) was significantly well correlated with IMT (r = 0.400; p < 0.0001) and PWV (r = 0.470; p < 0.0001). Multivariate regression analysis showed that baPWV, IMT, Fg, hematocrit, white blood cell count, and CRP were chosen as significant explanatory factors for T(B.) These results suggest that blood rheology may play an important role for atherosclerosis in patients with HD. 相似文献
993.
本文提出的基于重力"剥皮"的变密度多界面重震联合解释技术弥补了用单一物探方法难以探测沉积盆地盐膏层的不足。该技术采用重力"剥皮"法获得由盐膏层引起的剩余异常,据此成功地反演出了东营凹陷盐膏层的顶面深度和等效厚度。推断解释东营凹陷盐膏层由10个规模较大的盐膏体组成,呈北东向的扇状展布,顶面埋深 1700-3700m,北部埋深较大,南部埋深较小。反演结果与实钻误差仅为2.96%。 相似文献
994.
为了确保贫铀棒材表面防腐性能满足使用要求,需要准确地测量产品表面的镍镀层和锌镀层厚度。采用便携式X射线荧光光谱仪(PXRF)对贫铀棒材表面双镀层的各层厚度进行检测,实现了对镍镀层和锌镀层厚度非破坏性的测量。选用特征谱线强度分布均匀的镀层样品和未镀镀层的贫铀基体样品,采用PXRF检测,结果表明,基体射线对检测谱线无干扰。分别选取相同厚度镍镀层、不同厚度锌镀层的样品,相同厚度锌镀层、不同厚度镍镀层的样品,以及镍镀层、锌镀层厚度均不相同的样品,采用PXRF进行检测,结果表明,实验方法可识别相同基体上不同厚度的镍镀层和锌镀层,可实现镍锌组合镀层中两种镀层厚度的同时测量。根据贫铀棒材样品结构特点和镍镀层和锌镀层厚度的技术要求,设计制作了对比试样,分别绘制贫铀棒材样品镍镀层和锌镀层厚度与其对应特征峰强度的校准曲线,结果表明,校准曲线线性相关系数r均不小于0.999 4。采用实验方法检测贫铀棒材样品表面镍镀层和锌镀层厚度,同时在任意圆周上均匀地取6个检测点,采用金相显微镜法进行检测求得平均值,结果表明,实验方法测定结果相对标准偏差(n=6)不大于5.1%;与金相显微镜法基本一致,两种方法差值为-1.57~1.70 μm。 相似文献
995.
Ming DiEric Bersch Robert ClarkSteven Consiglio Gert LeusinkAlain C. Diebold 《Thin solid films》2011,519(9):2889-2893
We have used spectroscopic ellipsometry (SE) to measure layer thicknesses of HfO2/La2O3 and La2O3/HfO2 stacks on SiO2/p-Si. Two approaches to extract layer thicknesses from a single SE measurement were shown to be inaccurate, possibly due to similarities in the optical dispersions of HfO2 and La2O3. The approach where SE data was collected after deposition of each layer and only the thickness of the top layer was determined by modeling was found to be capable of accurately measuring the thickness of each layer. These conclusions are supported by angle resolved X-ray photoelectron spectroscopy (ARXPS), X-ray reflectivity (XRR) and Rutherford backscattering spectroscopy (RBS) measurements. 相似文献
996.
Retreatment of silicon slurry by membrane processes 总被引:1,自引:0,他引:1
Testa F Coetsier C Carretier E Ennahali M Laborie B Serafino C Bulgarelli F Moulin P 《Journal of hazardous materials》2011,192(2):440-450
The purpose of the present study is to develop a process to regenerate the polish liquid used in Chemical and Mechanical Polishing (CMP), called “slurry”, and more specifically Silicon CMP slurry. Physico-chemical analyses show a considerable dilution of slurry through washing waters used in polishing. Thus, this effluent has been characterised for a better identification of the deviations from the slurry of reference (Point Of Use). Hence, the principle is to regenerate this effluent by membrane processes. The ultrafiltration results obtained at laboratory scale have led to the development of an industrial prototype. An optimal utilisation of this treatment allows completing a two-step process: the reconcentration by ultrafiltration and a chemical adjustment by addition of concentrated slurry. A stable behaviour of the slurry at the different steps of the process has been observed. Polishing results are similar with retreated and POU slurries. Furthermore, the functioning at industrial scale permits to maintain the performances obtained on the laboratory pilot. 相似文献
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1000.
A Monte Carlo method is utilized to simulate the energy spectra for low-energy electron backscattered from different thin films deposited on different bulk substrates. A method of thickness determination for ultra-thin films is presented, which is obtained from the analysis of the basic characteristics of the energy spectra of backscattered electrons. This method is predicted to be particularly suitable for determining the thickness of ultra-thin films, and to be useful for both cases of light film on heavy substrate and heavy film on light substrate. The thickness resolution is estimated to be as high as subnanometer scale, provided the resolution of the electron energy spectrometer used to be high enough. 相似文献