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161.
162.
Molten salt electrolysis using CaCl2 is employed to produce pure titanium and its alloys directly from TiO2 and a mixture of elemental oxides, respectively, as an alternate to the Kroll process. This is because CaO, which is a reduction by-product, is highly soluble in CaCl2. Good-quality titanium containing only a small amount of residual oxygen has been successfully produced and scaled to industrial levels. Thermochemical and electrochemical bases are reviewed to optimize the process conditions. Several processes using molten salt are being examined for future progress in titanium processing.  相似文献   
163.
Endotoxin release from Pseudomonas aeruginosa treated with cell wall-active carbapenem antibiotics and its effect on the production of tumor necrosis factor alpha and nitric oxide were examined. Treatment of bacteria with imipenem induced much lower levels of endotoxin release than treatment with meropenem. The endotoxin released was demonstrated to be of the smooth type and O-specific polysaccharide-rich. The exposure of the filtrates of P. aeruginosa treated with imipenem to physiologically relevant cells caused low-level production of tumor necrosis factor alpha and nitric oxide, while similar treatment with meropenem induced high levels of production.  相似文献   
164.
The rapid advance of computerization in industrial package design has led to a strong tendency toward CAD/CAM systems using personal computers for quick design and trial manufacturing. New tools based on a database of the cushioning properties of packaging materials will be needed for the design of package cushioning. Using a compression testing machine with computer control, an attempt has been made to construct such a database with registered characteristics for 47 samples of foamed polyethylene, foamed polypropylene and foamed polyethylene-polystyrene. This database offers the following functions and is recorded on floppy disk: (i) calculation of static cushioning properties (value); (ii) print-out of the computed results; (iii) drawing characteristic figures for designing package cushioning; (iv) indicating optimum value of static cushioning properties; (v) additional registration of new samples.  相似文献   
165.
The translational movement of E-cadherin, a calcium-dependent cell-cell adhesion molecule in the plasma membrane in epithelial cells, and the mechanism of its regulation were studied using single particle tracking (SPT) and optical tweezers (OT). The wild type (Wild) and three types of artificial cytoplasmic mutants of E-cadherin were expressed in L-cells, and their movements were compared. Two mutants were E-cadherins that had deletions in the COOH terminus and lost the catenin-binding site(s) in the COOH terminus, with remaining 116 and 21 amino acids in the cytoplasmic domain (versus 152 amino acids for Wild); these are called Catenin-minus and Short-tailed in this paper, respectively. The third mutant, called Fusion, is a fusion protein between E-cadherin without the catenin-binding site and alpha-catenin without its NH2-terminal half. These cadherins were labeled with 40-nm phi colloidal gold or 210-nm phi latex particles via a monoclonal antibody to the extracellular domain of E-cadherin for SPT or OT experiments, respectively. E-cadherin on the dorsal cell surface (outside the cell-cell contact region) was investigated. Catenin-minus and Short-tailed could be dragged an average of 1.1 and 1.8 micron by OT (trapping force of 0.8 pN), and exhibited average microscopic diffusion coefficients (Dmicro) of 1.2 x 10(-10) and 2.1 x 10(-10) cm2/s, respectively. Approximately 40% of Wild, Catenin-minus, and Short-tailed exhibited confined-type diffusion. The confinement area was 0.13 micron2 for Wild and Catenin-minus, while that for Short-tailed was greater by a factor of four. In contrast, Fusion could be dragged an average of only 140 nm by OT. Average Dmicro for Fusion measured by SPT was small (0.2 x 10(-10) cm2/s). These results suggest that Fusion was bound to the cytoskeleton. Wild consists of two populations; about half behaves like Catenin- minus, and the other half behaves like Fusion. It is concluded that the movements of the wild-type E-cadherin in the plasma membrane are regulated via the cytoplasmic domain by (a) tethering to actin filaments through catenin(s) (like Fusion) and (b) a corralling effect of the network of the membrane skeleton (like Catenin-minus). The effective spring constants of the membrane skeleton that contribute to the tethering and corralling effects as measured by the dragging experiments were 30 and 5 pN/micron, respectively, indicating a difference in the skeletal structures that produce these two effects.  相似文献   
166.
A scanning interference electron microscope (SIEM) has been developed for periodical nanostructure fabrication. This system can produce electron interference fringes with a period from 2 nm to several ten microns. Fabrications of periodical nanostructures with 23 to 170 nm period have been demonstrated by transferring electron interference fringe onto semiconductor surfaces.  相似文献   
167.
Phase equilibria on the Fe-Cu side in the Fe-Cu-X (X: Co, Cr, Si, V) system were experimentally determined over the temperature range of 1073–1273 K. Based on the present results and previous works, the thermodynamic assessments of the phase equilibria in the Fe-Cu-X system were evaluated using the Calculation of Phase Diagram (CALPHAD) method. The Gibbs energies (G) of the bcc, fcc, and liquid phases are described by the subregular solution model, and a set of thermodynamic parameters enable us to calculate various isothermal and vertical sections and the miscibility gaps of the solid and liquid phases.  相似文献   
168.
169.
This paper describes a method of visualizing customer expectation as a network. Customer expectation is an important factor in succeeding in service, because the expectation depends on service evaluation. Therefore, to develop a service by co-creation, the service provider needs the customer expectation. To extract customer expectation, we first extract a co-occurrence network called collective intelligence expectation network from Web texts about a target service. From this network, we aggregate the personalized expectation acquired from questionnaire and generate a customer expectation network.  相似文献   
170.
This paper proposes a novel approach to generate and analyze path model by structure equation modeling (SEM). SEM is an important technique to carry out causal analysis based on path model. As such, constructing path models, which result in reliable analysis, are important in SEM. LSA-based method, which is used to build a path model from text data, is proposed. However, this method requires each document to belong to one topic; thus, the model cannot express natural variables and relationships. Therefore, this paper extends the existing approach to latent Dirichlet allocation (LDA) and generates a path model from the extracted topics by LDA. Experiments using review text data can confirm the feasibility and applicability of the proposed process.  相似文献   
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