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81.
82.
3 ward climate scales were derived from 2 independent studies linking treatment environments as perceived by patients and staff to treatment outcome as assessed by ward dropout, release, and community tenure rates. Patients and staff from 7 large and 8 small Veterans Administration hospital wards completed the Ward Atmosphere Scales. Patients and staff agreed in perceiving wards with high dropout rates as low in involvement, support, order and organization, and program clarity, whereas wards with high release rates were perceived as strongly emphasizing practical orientation, but as relatively "unexpressive." Wards that kept patients out of the hospital longest were seen as emphasizing autonomy and independence, practical orientation, order and organization, and the open expression of feelings, particularly angry feelings. It is concluded that some relatively consistent findings are emerging from studies in this area. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
We propose image processing algorithms for measuring two-dimensional distributions of linear birefringence using a pair of variable retarders. Several algorithms that use between two and five recorded frames allow us to optimize measurements for speed, sensitivity, and accuracy. We show images of asters, which consist of radial arrays of microtubule polymers recorded with a polarized light microscope equipped with a universal compensator. Our experimental results confirm our theoretical expectations. The lowest noise level of 0.036 nm was obtained when we used the five-frame technique and four-frame algorithm without extinction setting. The two-frame technique allows us to increase the speed of measurement with acceptable image quality. 相似文献
84.
Rudolf Richter Thomas Heege Viacheslav Kiselev Daniel Schläpfer 《International journal of remote sensing》2013,34(23):8044-8056
An accurate atmospheric correction (AC) of Earth remote-sensing data in the spectral region 450–800 nm has to account for the ozone gas absorption influence. Usual operational AC codes employ a fixed ozone concentration corresponding to a climatologic average for a certain region and season, e.g. the mid-latitude summer atmosphere of the Moderate Resolution Atmospheric Transmission (MODTRAN) code. The reasons for a fixed ozone column are that ozone does not vary rapidly on a spatial and temporal scale, and additionally, the look-up table (LUT) size for AC is already big. This means that another degree of freedom for the ozone parameter would dramatically increase the size of the LUT database and the time required for LUT interpolation. In order to account for this effect, we use already existing LUTs that were calculated for a certain ozone reference level, e.g. an ozone column of g = 330 Dobson Units (DU) for MODTRAN’s mid-latitude summer atmosphere. Then the deviation of the top-of-atmosphere (TOA) radiance ΔL(g) from the reference level L(g = 330) is calculated as a function of solar and view geometries. The calculation is performed for a set of 36 wavelengths in the ozone-sensitive spectrum (450–800 nm) and five ozone columns. The last step computes the linear regression coefficients for each wavelength and geometry. The results are stored in a small table (11 kB). It is shown that the ozone influence is accurately accounted for by multiplying the modelled radiance L(g = 330) with a factor depending on g and wavelength yielding TOA radiance relative errors smaller than 0.5% for a wide range of ozone concentrations between 180 and 500 DU. Selected examples of a sensitivity study of the ozone effect on the retrieval of water constituents demonstrate the need to account for ozone in the AC step. 相似文献
85.
Rudolf Richter Xingjuan Wang Martin Bachmann Daniel Schläpfer 《International journal of remote sensing》2013,34(10):2931-2941
Optical satellite images are often contaminated with cirrus clouds. Thin cirrus can be detected with a channel at 1.38 μm, and an established cirrus removal method exists for visible/near-infrared (VNIR) channels in atmospheric window regions, which was demonstrated with Moderate Resolution Imaging Spectrometer (MODIS) data. This contribution addresses open issues of cirrus correction for Sentinel-2 type of instruments, that is, future spaceborne sensors such as Sentinel-2 or similar instruments. These issues are (i) an extension of the existing technique to account for cirrus during the water vapour retrieval (channel at 0.94 μm) and surface reflectance calculation to avoid reflectance artefacts at 0.94 μm, (ii) a discussion of options concerning cirrus removal in the short-wave infrared (SWIR, channels at 1.6 and 2.2 μm) region and (iii) an analysis of channel parallax (view angle) requirements to achieve a high-quality cirrus removal. 相似文献
86.
Rudolf Pernis Jozef Kasala 《The International Journal of Advanced Manufacturing Technology》2013,65(5-8):1081-1089
Nowadays, the development of tube drawing process with a floating plug technique has moved our limit up to the production of thick-walled tubes; production of which still belongs to marginal techniques which are different from drawing of standard tubes. The submitted paper is basically a survey of research in fundamental characteristics of tube drawing with a floating plug with the aim to summarize some important results from the theory, which have not yet been published in any English publication. The purpose of this survey is to fill the gap in English literature to promote transfer and exploitation of knowledge. Research in fundamental characteristics was further developed and conditions under which it is possible to draw thick-walled tubes are defined. Confirmed possibility of thick-walled tubes drawing with support provided by a floating plug having negative overlap is the result of theoretical study and practical verification, which enables further moving of drawing process limit. 相似文献
87.
Matthias Augustin Alfonso Caiazzo André Fiebach Jürgen Fuhrmann Volker John Alexander Linke Rudolf Umla 《Computer Methods in Applied Mechanics and Engineering》2011,200(47-48):3395-3409
The performance of several numerical schemes for discretizing convection-dominated convection–diffusion equations will be investigated with respect to accuracy and efficiency. Accuracy is considered in measures which are of interest in applications. The study includes an exponentially fitted finite volume scheme, the Streamline-Upwind Petrov–Galerkin (SUPG) finite element method, a spurious oscillations at layers diminishing (SOLD) finite element method, a finite element method with continuous interior penalty (CIP) stabilization, a discontinuous Galerkin (DG) finite element method, and a total variation diminishing finite element method (FEMTVD). A detailed assessment of the schemes based on the Hemker example will be presented. 相似文献
88.
Sunmi Shin Rudolf Schäfer Bruno C. De Cooman 《Metallurgical and Materials Transactions A》2013,44(9):4239-4247
Magnetic materials such as Fe-Si alloys are magnetized by the rearrangement of their magnetic microstructure and domain wall motion. Understanding magnetic microstructures in the interior of a ferromagnet is essential for the control and reduction of energy losses in electrical devices. The three-dimensional magnetic microstructure of solids is still unknown due to the lack of an appropriate observation technique, and the magnetic domain wall structure inside a ferromagnet has never been observed with sufficiently high resolution. The first observation of the 3D magnetic microstructure of an Fe-6.6 pct Si alloy with a high spatial resolution is reported. The domain walls known to exist inside positive anisotropy cubic materials, i.e., the 180-deg domain walls and the 90-deg domain walls, were analyzed for the first time. The structure and orientation of the domain walls were found to be very different from the prediction of current theoretic models. 相似文献
89.
UV-vis absorption spectra and cyclic voltammograms of a selection of substituted thiophenes and their oligomers carrying trifluoracetyl acetone functional groups have been obtained. A comparison with calculated values of HOMO-LUMO energies (the former corresponding to the ionization potentials Ei) shows strong correlations between calculated and experimentally obtained data; they are in close agreement with estimates in terms of electron-donating and -withdrawing effects from an empirical point of view. 相似文献
90.
Radovan Ćirić Svetislav Čantrak Karlo T. Raić Rebeka Rudolf Ivan Anžel 《Metals and Materials International》2009,15(5):831-841
The paper presents the viscoplastic phenomena observed during the rotational friction-welding process of high-speed steel
M2 (AISI SAE) with carbon steel 1060 (AISI SAE). The structure, phase composition and distribution of the carbide phase in
the friction plane and adjoining zones are examined by using optical microscopy (OM) with a system for quantitative analysis,
and scanning electron microscopy (SEM) in addition to EDS analysis. The experimentally-checked mathematical relationship is
suggested for the calculation of the radial movements of the carbide phase, immediately next to the friction plane. On the
basis of qualitative and quantitative evaluation of the microstructural and rheological appearances, a model of carbide phase
distribution is also established in the viscoplastic and viscous layers in the area of the friction plane. 相似文献