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11.
The murine monoclonal antibody BR55-2 is directed against thetumor-associated antigen Lewis Y oligosaccharide. The LewisY core antigen is a difucosylated structure consisting of fourhexose units. Analysis of binding profiles of lactoseries isomericstructures by BR55–2 suggest that the binding epitopeincludes the OH-4 and OH-3 groups of the ß-D-galactoseunit, the 6-CH3 groups of the two fucose units and the N-acetylgroup of the subterminal ß-D-N-acetylglucosamine (ßDGlcNAc).To elucidate the molecular recognition properties of BR55–2for the Y antigen, BR55–2 was cloned, sequenced and itsthree-dimensional structure was examined by molecular modeling.The crystal structure of BR96, another anti-Lewis Y antibody,solved in complex with a nonoate methyl ester Lewis Y tetrasaccharide,and the lectin IV protein in complex with a Lewis b tetrasaccharidecore were used as a guide to probe the molecular basis for BR55–2antigen recognition and specificity. Our modeling study showsthat BR55–2 shares similar recognition features for thedifucosylated type 2 lactoseries Lewis Y structure observedin the BR96-sugar complex. We observe that a major source ofspecificity for the Lewis Y structure by anti-Y antibodies emanatesfrom interaction with the ß-D-N-acetylglucosamineresidue and the nature of the structures extended at the reducingsite of the fucosylated lactosoamine.  相似文献   
12.
Frequency-resolved communication maps provide a coarse-grained, global mapping of energy transport channels in a protein as a function of frequency of modes that carry energy. We illustrate the approach with a study of the homodimeric hemoglobin of Scapharca inaequivalvis, which exhibits cooperativity during ligand binding. We compare energy transport between the two hemes of the unliganded and oxygenated protein, which is mediated by water as well as residues forming a hydrogen-bonding network at the interface between the globules, and lies along the pathway for allosteric transitions observed in time-resolved X-ray studies. Non-equilibrium molecular simulations on energy transport from the heme corroborate the energy transport pathways identified by the communication maps.  相似文献   
13.
A fundamental study of microelectric discharge machining (μ-EDM) based on the physics of single spark and electrothermal theory has been carried out. The machining phenomena in the μ-EDM process are investigated through simulations using finite element method. By creating the single-discharge crater, the topography is measured using an atomic force microscope and the simulation results compared with the experimental result. A temperature distribution along the radius and depth of the workpiece is thus reported. For verification purpose, single-discharge experiments with RC pulse circuit are performed with tungsten carbide as the electrode and stainless steel as the workpiece. The diameter-to-depth ratios of the crater obtained by the simulation and the experiments are 2.92 and 2.67, respectively. The simulation results are found to be in close agreement with experimental results.  相似文献   
14.

Nowadays, next-generation networks such as the Internet of Things (IoT) and 6G are played a vital role in providing an intelligent environment. The development of technologies helps to create smart city applications like the healthcare system, smart industry, and smart water plan, etc. Any user accesses the developed applications; at the time, security, privacy, and confidentiality arechallenging to manage. So, this paper introduces the blockchain-defined networks with a grey wolf optimized modular neural network approach for managing the smart environment security. During this process, construction, translation, and application layers are created, in which user authenticated based blocks are designed to handle the security and privacy property. Then the optimized neural network is applied to maintain the latency and computational resource utilization in IoT enabled smart applications. Then the efficiency of the system is evaluated using simulation results, in which system ensures low latency, high security (99.12%) compared to the multi-layer perceptron, and deep learning networks.

  相似文献   
15.
Phase transition in L-alaninium oxalate is studied by using TG, DTA and photoacoustic spectroscopy. A sharp transition at 378 K by photoacoustics is observed whereas at the same temperature the endothermic energy change observed by TG and DTA is not very sharp. This is discussed in detail with reference to the other known data for the organic crystals.  相似文献   
16.
The integration of electrospinning and electrospraying to prepare the fibrous catalytic filter membrane is demonstrated. The non-conductive polyethylene oxide (PEO) is blended with (±)-camphor-10-sulfonic acid (CSA) doped conductive polyaniline (PANi) for electrospinning. The conductive CSA/PANi-PEO composite fibers are produced upon electrospinning, which are used as the conductive collector for electrospraying process by which titanium dioxide (TiO2) nanoparticles (NPs) are sprayed and allowed to adsorb on the fibers. The degree of adsorption and dispersion of nano TiO2 catalysts on the surface of the CSA/PANi-PEO fibers exhibit a stronger dependence on weight percentage (wt%) of PANi in PEO solution and the strength of electrical conductivity of the fibers used during electrospraying. CSA/PANi-PEO fibers as collector reduce the wastage of TiO2 NPs during electrospraying to lesser than 5%. Among the three different composition of PANi studied, PEO with 12 wt% PANi yields very uniform diameter and beads-free fibrous structure with higher electrical conductivity. 12 wt% CSA/PANi-PEO fibrous membrane is found to support for greater dispersion of TiO2 NPs. The photocatalytic activity of the as-prepared TiO2-PANi-PEO catalytic membrane is tested against the toxicant simulant 2-chloroethyl phenyl sulfide (CEPS) under the ultraviolet light irradiation. It is observed that the TiO2 nanoparticles catalysts embedded PANi-PEO fibrous membrane decontaminated the toxicant CEPS significantly, which is due to uniform dispersion of the catalysts produced by the methodology.  相似文献   
17.
18.
A Multi-radio 802.11 Mesh Network Architecture   总被引:2,自引:0,他引:2  
The focus of this paper is to offer a practical multi-radio mesh network architecture that can realize the benefits of multiple radios. Our architecture provides solutions to challenges in three key areas. The first is the construction of a split wireless router that enables modular wireless mesh routers to be constructed from commodity hardware. The second is the design of a centralized channel assignment algorithm that considers the inter-dependence between channel assignment and routing in order to create high-throughput channel-diversified routes. Third is the design and implementation of several communication protocols that are necessary to make our architecture operational. Our system is comprehensively evaluated on a 20-node multi-radio wireless testbed. Results demonstrate that our architecture makes feasible the deployment of large-scale high-capacity multi-radio mesh networks built entirely with commodity hardware. Our implementation is available to the community for research and development purposes.  相似文献   
19.
Multilayers of CeO2/ZrO2 thin films were deposited on Si (100) substrates using pulsed laser deposition at an optimized oxygen partial pressure of 3×10−2 mbar and at room temperature. The CeO2 layer thickness was 10 nm, while the ZrO2 layer thickness was varied as 10, 20 and 30 nm. CeO2 and ZrO2 layers were deposited alternately to obtain 25 bilayers. High temperature x-ray diffraction (HTXRD) results showed that the multilayer films had cubic ceria and tetragonal ZrO2. Thermal expansion coefficients were calculated for CeO2 and t-ZrO2 and found to increase with the decrease of ZrO2 layer thickness. The cross sectional transmission electron microscopy (XTEM) of CeO2/ZrO2 multilayer also indicated that ceria was found to be in cubic phase while zirconia contained predominantly tetragonal phase along with cubic phase in thermally annealed specimen.  相似文献   
20.
Nanoscale materials have been considered for and been in use in a variety of industrial engineering applications. The surface tension of silver and copper were calculated at various temperatures using non-ideal or real solution characteristics. The surface concentration of individual components was also calculated. The surface concentration of silver in a binary silver copper system is higher in spite of its lower surface tension as a pure component. It is also shown that the melting temperature of individual elements decrease with decrease in particle size. This trend is true for most metallic elements and is pronounced below a particle size of 20 nm.  相似文献   
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