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801.
Semantically enabled service-oriented architecture focused on principles of service orientation, semantic modeling, intelligent and automated integration defines grounds for a cutting-edge technology which enables new means to integration of services, more adaptive to changes in business requirements which occur over systems’ lifetime. We define the architecture starting from a global perspective and through Web service modeling ontology as its semantic service model we narrow down to its services, processes and technology we use for the reference implementation. On a B2B integration scenario we demonstrate several aspects of the architecture and further describe the evaluation of the implementation according to a community-agreed standard evaluation methodology for semantic-based systems.  相似文献   
802.
Application of the inverse analysis to the interpretation of hot tensile tests is the main objective of the work. Tensile tests were performed for carbon‐manganese steel samples at 1000°C and at three ram velocities. The measured temperature distribution was used as boundary condition in the finite element model of the direct problem. Recorded loads and elongation of the sample were used as input for the inverse analysis. The flow stress, recalculated for isothermal conditions and constant strain rate deformation, was determined as a function of strain up to the maximum deformations achieved in the neck. Validation of the flow stress model based on comparison of the measured loads with the finite element predictions for the developed Theological model, confirmed reasonably good accuracy of the procedure. Additionally, sensitivity of the measured parameters (loads and radius of the neck at certain elongation) with respect to the rheological parameters has been performed.  相似文献   
803.
To evaluate the antioxidant activity of potential synthetic enzyme mimetics, we prepared new five copper(II) complexes via a self-assembly method and named them [Cu(2-(HOCH2)py)3](ClO4)2 (1), [Cu(2-(HOCH2)py)2(H2O)2]SiF6 (2), [Cu2(2-(HOCH2CH2)py)2(2-(OCH2CH2)py)2](ClO4)2 (3), [Cu(pyBIm)3](BF4)2·1.5H2O (4) and [Cu(py2C(OH)2)2](ClO4)2 (5). The synthetic protocol involved N,O- or N,N-donors: 2-(hydroxymethyl)pyridine (2-(HOCH2)py), 2-(hydroxyethyl)pyridine (2-(HOCH2CH2)py), 2-(2-pyridyl)benzimidazole (pyBIm), di(2-pyridyl)ketone (py2CO). The obtained Cu(II) complexes were fully characterised by elemental analysis, FTIR, EPR, UV-Vis, single-crystal X-ray diffraction and Hirshfeld surface analysis. Crystallographic and spectroscopic analyses confirmed chromophores of both monomeric ({CuN3O3} (1), {CuN2O4} (2), {CuN6} (4), {CuN4O2} (5)) and dimeric complex ({CuN2O3} (3)). Most of the obtained species possessed a distorted octahedral environment, except dimer 3, which consisted of two copper centres with square pyramidal geometries. The water-soluble compounds (1, 3 and 5) were selected for biological testing. The results of the study revealed that complex 1 in solutions displayed better radical scavenging activity than complexes 3, 5 and free ligands. Therefore, complex 1 has been selected for further studies to test its activity as an enzyme mimetic. The chosen compound was tested on the erythrocyte lysate of two groups of patients after undergoing chemotherapy and chemoradiotherapy. The effect of the tested compound (1) on enzyme activity levels (TAS, SOD and CAT) suggests that the selected complex can be treated as a functional mimetic of the enzymes.  相似文献   
804.
Copper (Cu) could serve as antibacterial coating for Ti6Al4V implants. An additional cell-adhesive layer might compensate Cu cytotoxicity. This study aimed at in vitro and in vivo evaluation of low-temperature plasma treatment of Ti6Al4V plates with Ti/Cu magnetron sputtering (Ti6Al4V–Ti/Cu), plasma-polymerized ethylenediamine (Ti6Al4V–PPEDA), or both (Ti6Al4V–Ti/Cu–PPEDA). Ti6Al4V–Ti/Cu and Ti6Al4V–Ti/Cu–PPEDA had comparable in vitro Cu release and antibacterial effectiveness. Following intramuscular implantation of Ti6Al4V–Ti/Cu, Ti6Al4V–PPEDA, Ti6Al4V–Ti/Cu–PPEDA and Ti6Al4V controls for 7, 14 and 56 days with 8 rats/day, peri-implant tissue was immunohistochemically examined for different inflammatory cells. Ti6Al4V–PPEDA had more mast cells and NK cells than Ti6Al4V, and more tissue macrophages, T lymphocytes, mast cells and NK cells than Ti6Al4V–Ti/Cu–PPEDA. Ti6Al4V–Ti/Cu had more mast cells than Ti6Al4V and Ti6Al4V–Ti/Cu–PPEDA. Results indicate that PPEDA-mediated cell adhesion counteracted Cu cytotoxicity. Ti6Al4V–Ti/Cu–PPEDA differed from Ti6Al4V only for mast cells on day 56. Altogether, implants with both plasma treatments had antibacterial properties and did not increase inflammatory reactions.  相似文献   
805.
806.
This study examined predictors of creative self-efficacy (CSE) within a large sample (N=1,878) of Polish school students. Results indicate that creative self-efficacy is significantly predicted by creative abilities (measured by Test of Creative Thinking-Drawing Production) as well as self-reported originality, with 12% of the creative self-efficacy variance predicted by these criteria. Analysis of the potential antecedents of creative self-efficacy showed that it is connected with gender, socioeconomic status, and locality size. Socioeconomic status (SES) was a positive predictor of CSE. Male students were characterized by higher self-efficacy than female students and they also tended to overestimate their creative self-efficacy as predicted by abilities. In turn, females underestimated their creative self-efficacy. Socioeconomic status moderated the relations between creative abilities and creative self-efficacy, with stronger associations between abilities and efficacy in high SES groups. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
807.
Resonant frequencies of the two-dimensional plasma in field effect transistors (FETs) increase with the reduction of the channel dimensions and can reach the Terahertz (THz) range. Nonlinear properties of the plasma/electron gas in the transistor channel can be used for the rectification and detection of THz radiation. The excitation of plasma waves by sub-THz and THz radiation was demonstrated for short gate transistors at cryogenic temperatures. At room temperature plasma oscillations are usually overdamped, but the FETs can still operate as efficient broadband rectifiers/detectors in the THz range. We present a few recent experimental results on THz detection by FETs showing some new ways of improvement of FETs for THz imaging at room temperature as well as the new physical phenomena like detection in quantizing magnetic fields. We also demonstrate THz emission properties of GaN based FETs.  相似文献   
808.
Silica is a very promising material for micro-devices produced by rapid prototyping techniques due to its high transparency, thermal and chemical resistance. UV curable dispersions for rapid prototyping methods such as stereolithography should posses specific rheological properties which are crucial for such applications. We developed highly filled, low viscosity silica dispersions (up to 60 vol%) in UV curable, acrylate based systems. The influence of silica particle size, solid loading, temperature and shear rate on the viscosity of dispersions was investigated. The dispersions exhibited different types of shear thickening depending mainly on the size of particles. The critical shear rate defined as the onset of shear thickening, was found to be dependent on temperature, particle size, solid loading of the dispersions. The understanding of these rheological properties enables the design of new dispersions that meet rapid prototyping process requirements.  相似文献   
809.
Pesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in the environment is a particular danger. It is therefore crucial to monitor pesticide residues using all available analytical methods. The analysis of environmental samples for the presence of pesticides is very difficult: the processes involved in sample preparation are labor-intensive and time-consuming. To date, it has been standard practice to use large quantities of organic solvents in the sample preparation process; but as these solvents are themselves hazardous, solvent-less and solvent-minimized techniques are becoming popular. The application of Green Chemistry principles to sample preparation is primarily leading to the miniaturization of procedures and the use of solvent-less techniques, and these are discussed in the paper.  相似文献   
810.
Experimental and numerical investigation of heat transfer and fluid flow were conducted for classic heat exchanger elements (flat plate with fin-tubes in-line, staggered and with vortex generators) and corrugated-undulated ducts under transitional and weakly turbulent conditions.The dependence of average heat transfer and pressure drop on Reynolds number and geometrical parameters was investigated. Distributions of local heat transfer coefficient were obtained by using liquid crystal thermography and surface-averaged values were computed. Three-dimensional numerical simulations were conducted by a finite-volume method using a low-Reynolds number k-e model under the assumption of fully developed flow. Computed flow fields provided otherwise inaccessible information on the flow patterns and the mechanisms of heat transfer enhancement.  相似文献   
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