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41.
Vladimir Ćurić Joakim Lindblad Nataša Sladoje Hamid Sarve Gunilla Borgefors 《Pattern Analysis & Applications》2014,17(1):141-152
We propose a new distance measure, called Complement weighted sum of minimal distances, between finite sets in ${\mathbb Z }^n$ and evaluate its usefulness for shape registration and matching. In this set distance the contribution of each point of each set is weighted according to its distance to the complement of the set. In this way, outliers and noise contribute less to the new similarity measure. We evaluate the performance of the new set distance for registration of shapes in binary images and compare it to a number of often used set distances found in the literature. The most extensive evaluation uses a set of synthetic 2D images. We also show three examples of real problems: registering a set of 2D images extracted from synchrotron radiation micro-computed tomography (SR $\upmu $ CT) volumes depicting bone implants; the difficult multi-modal registration task of finding the exact location of a 2D slice of a bone implant, as imaged by a light microscope, within a 3D SR $\upmu $ CT volume of the same implant; and finally recognition of handwritten characters. The evaluation shows that our new set distance performs well for all tasks and outperforms the other observed distance measures in most cases. It is therefore useful in many image registration and shape comparison tasks. 相似文献
42.
Gregory B. Furman Shaul D. Goren Victor M. Meerovich Vladimir L. Sokolovsky 《Quantum Information Processing》2014,13(12):2759-2768
We study behavior of quantum discord, a kind of quantum correlation, in systems of dipole–dipole interacting spins in an external magnetic field in the whole temperature range ( \(-\infty ). It was shown that negative temperatures, which are introduced to describe inversions in the population in a finite level system, provide more favorable conditions for emergence of quantum correlations including entanglement. We show that at negative temperature, the correlations become more intense and discord exists between remote spins being in separated states. 相似文献
43.
Thermoplastic extrusion—the mechanism of the formation of extrudate structure and properties 总被引:6,自引:0,他引:6
Vladimir B. Tolstoguzov 《Journal of the American Oil Chemists' Society》1993,70(4):417-424
Systems processed by thermoplastic extrusion can be regarded as heterophase polymer melts of incompatible water-plasticized
biopolymers. In the process of thermoplastic extrusion, proteins and polysaccharides are melted at high pressure and temperature
below the temperature region of their thermal decomposition. Dispersed particles of these systems can be deformed in flow.
The mixed-melt anisotropic structure, formed in flow, is fixed by rapid conversion of the melt jet that lets the extruder
die from a viscous state to a rubber-like state and then to a glassy state caused by cooling and drying. Incompatibility of
proteins and polysaccharides in their water-plasticized melt mixtures impacts on structure formation and texturization during
thermoplastic extrusion.
Presented at the 20th ISF World Congress and 83rd AOCS Annual Meeting and Expo, May 10–14, 1992, Toronto, Ontario, Canada. 相似文献
44.
The electrochemical deposition and dissolution of aluminium on glassy carbon, platinum and gold electrodes in chloraluminate melts have been investigated using linear sweep voltammetry and potentiostatic pulse techniques. It was shown that deposition of aluminium on the glassy carbon electrode at low overpotentials takes place by 3-D progressive nucleation and growth, with the incorporation of atoms in the crystal lattice as the rate-determining step. At overpotentials higher than –100 mV vs Al, in the melts containing more than 52 mol % of AlCl3, diffusion of Al2Cl
7
–
, takes over the control of deposition of aluminium. Alloying of platinum and gold electrodes with aluminium from the melt occurs in the underpotential region. 相似文献
45.
46.
The diffusion of 57 Co isotope on the MgO (100) surface was investigated by the edge-source method. The surface diffusion parameter, αDs δ, where α is the segregation factor, Ds the surface diffusion coefficient, and δ the thickness of the high-diffusivity layer, was determined over the temperature region 750° to 1250°C. An Arrhenius plot shows a break at ∼1100°C. Below this temperature ionic or localized transport predominates and above it nonlocalized transport seems to predominate. The divalent Co ion diffuses faster than the trivalent Cr ion in the surface layer. The apparent activation energies for the localized surface diffusion of 57 Co and 59 Cr are 59±12 and 110±12 kj/mol, respectively. 相似文献
47.
Comparative data on the molecular weight distribution of polymers obtained by polymerization of ethylene, propylene and 1-hexene, and copolymerization of ethylene with α-olefins over the titanium-magnesium catalysts (TMC) in the absence and presence of hydrogen are presented. In contrast to the ethylene polymerization, in the cases of propylene and 1-hexene polymerization and copolymerization of ethylene with α-olefins, the hydrogen addition is characterized by noticeable narrowing of the molecular weight distribution (MWD) due to lower contribution of the MWD component with high molecular weight. This result is an evidence of the increased reactivity of TMC active sites producing high molecular weight poly-α-olefins and copolymers of ethylene with α-olefins in the chain transfer reaction with hydrogen. It is suggested that the increased reactivity of these sites in the transfer reaction with hydrogen appears after the 2,1-addition of α-olefin to the growing polymer chain. 相似文献
48.
Vladimir Brailovski Patrick Terriault Sergei Prokoshkin 《Journal of Materials Engineering and Performance》2002,11(6):614-621
Shape memory alloys (SMA) suffer from the same impairing mechanisms experienced during cycling loading by classic alloys.
Moreover, SMA fatigue behavior is greatly influenced by thermomechanical cycling through the zone of thermoelastic phase transformation,
which is the basis of shape memory and superelasticity effects. Since the fatigue resistance of any material can be improved
by an appropriate thermomechanical treatment, in the present work combined differential scanning calorimetry and microhardness
testing were used to determine an optimum annealing temperature for the cold-worked Ni-50.1%Ti alloy. The optimization is
based on the assumption that latent heat of transformation is proportional to the mechanical work generated by SMA upon heating,
while material hardness is related to the yield stress of the material. It is supposed that an optimum trade-off in these
two properties guarantees the best dimensional and functional stability of SMA devices. The level and stability of the mechanical
work generated by the material during low-cycle fatigue testing are considered criteria for the material performance and thus
of the validity of the proposed optimization procedure. 相似文献
49.
Platforms with automatic memory management, such as the JVM, are usually considered free of memory leaks. However, memory leaks can happen in such environments, as the garbage collector cannot free objects, which are not used by the application anymore, but are still referenced. Such unused objects can eventually fill up the heap and crash the application. Although this problem has been studied extensively, nevertheless, there are still many rooms for improvement in this area. This paper describes the statistical approach for memory leak detection, as an alternative, along with a commercial tool, Plumbr, which is based on the method. The tool is later analyzed with three case studies of real applications and in the process also analyzes strengths and weaknesses of the statistical approach for memory leak detection. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
50.