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991.
992.
This letter develops a novel algorithm for lip motion analysis arising as a result of feeling amused after watching television comedy programs as emotion‐eliciting stimuli. The analysis is based on measuring the variance of new lip motion features extracted from pronouncing some sentences after watching the stimuli. The results of the conducted experiment show that these features can serve as efficient indices for determining the occurrence of amusement feelings. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
993.
In this paper, we propose an efficient algorithm to recognize actions of human interaction. Unlike previous algorithms using two participants' actions, the proposed algorithm estimates the action contribution of participants to determine which participant's action is the major action for correct interaction recognition. To estimate this contribution, we construct a contribution interaction model for each interaction category in which both participants carry out major actions. Using the contribution models, we design a method that automatically estimates the contribution of participants and classifies interaction samples into “co‐contribution” and “single‐contribution” interactions. At the same time, the major actions in the “single‐contribution” interactions are determined. We evaluate our method on the UT‐interaction dataset and our original interaction dataset (LIMU). Recognition results indicate the robustness of the proposed method and the high estimation accuracy obtained: estimation accuracies of 96 and 98% in set 1 and set 2 of the UT dataset, respectively, and 97.8% in the LIMU dataset. Based on the estimation results, we extract the major action information for interaction recognition. Average recognition accuracies of 93.3% in set 1 and 91.7% in set 2 of the UT dataset were obtained. Our result is at least 5% better than those obtained with previous algorithms. For the LIMU dataset, recognition accuracy reached 91.1%. It was 8.9% higher than the recognition result without contribution estimation. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
994.
A dispersion interferometer is one of the promising methods of the electron density measurement on large and high density fusion devices. This paper describes development of a CO(2) laser dispersion interferometer with a photoelastic modulator for phase modulation. In order to make the dispersion interferometer free from variations of the detected intensity, a new phase extraction method is introduced: The phase shift is evaluated from a ratio of amplitudes of the fundamental and the second harmonics of the phase modulation frequency in the detected interference signal. The proof-of-principle experiments demonstrate the feasibility of this method.  相似文献   
995.
We determined the genetic background that would result in a more optimal display of heterologously expressed β-glucosidase (BGL) on the cell surface of yeast Saccharomyces cerevisiae. Amongst a collection of 28 strains carrying deletions in genes for glycosylphosphatidyl inositol (GPI)-anchored proteins, the Δsed1 and Δtos6 strains had significantly higher BGL-activity whilst maintaining wild type growth. Absence of Sed1p, which might facilitate incorporation of anchored BGL on the cell-surface, could also influence the activity of BGL on the cell surface with the heterologous gene being placed under the control of the SED1 promoter. For the evaluation of its industrial applicability we tested this system in heterologous and homogenous SED1-disruptants of sake yeast, a diploid S. cerevisiae strain, in which either the SED1 ORF or the complete gene including the promoter was deleted by use of the high-efficiency loss of heterozygosity method. Evaluation of disruptants displaying BGL showed that deletion of the SED1 ORF enhanced BGL activity on the cell surface, while additional deletion of the SED1 promoter increased further BGL activity on the cell surface. Compared to heterozygous disruption, homozygous disruption resulted generally in a higher BGL activity. Thus, homozygous deletion of both SED1 gene and promoter resulted in the most efficient display of BGL reaching a 1.6-fold increase of BGL-activity compared to wild type.  相似文献   
996.
We investigated the hydrothermal conversion of the carbohydrates including glucose, cellulose, and starch to lactic acid using NaOH and Ca(OH)2 as alkaline catalysts. Both catalysts significantly promoted the lactic acid formation. The highest yield of lactic acid from glucose was 27% with 2.5 M NaOH and 20% with 0.32 M Ca(OH)2 at 300°C for 60 s. The lactic acid yields from cellulose and starch were comparable with the yield from glucose with 0.32 M Ca(OH)2 at 300°C, but the reaction time in the case of cellulose was 90 s. The mechanism of lactic acid formation from glucose was discussed by identifying the intermediate products. Lactic acid may be formed via the formation of aldoses of two to four carbons including aldose of three carbons, which are all formed by reverse aldol condensation and double bond rule of hexose. This implies that carbon–carbon cleavage occurs at not only C3? C4 but also at C2? C3. © 2010 American Institute of Chemical Engineers AIChE J, 2010  相似文献   
997.
Fabrication and characterization of heterojunction solar cells of tetracyanoquinodimethane (TCNQ)/copper phthalocyanine (CuPc) and zinc phthalocyanine (ZnPc) were carried out. The light-induced charge separation with charge transfer was investigated by light-induced current density and optical absorption. In both cases of the TCNQ/CuPc and TCNQ/ZnPc solar cells, the TCNQ thin film worked for strong electron-accepting layer as n-type semiconductor. These behaviors would be originated in charge transfer of excited electron from CuPc and ZnPc to TCNQ. The photovoltaic mechanism was discussed on the basis of the experimental results.  相似文献   
998.
Surface-mediated gene transfer systems using apatite (Ap)-based composite layers have received increased attention in tissue engineering applications owing to their safety, biocompatibility and relatively high efficiency. In this study, DNA-antibody–apatite composite layers (DA–Ap layers), in which DNA and antibody molecules are immobilized within a matrix of apatite nanocrystals, were fabricated using a biomimetic coating process. They were then assayed for their gene transfer capability for application in a specific cell-targeted gene transfer. A DA–Ap layer that was fabricated with an anti-CD49f antibody showed a higher gene transfer capability to the CD49f-positive CHO-K1 cells than a DNA–apatite composite layer (D–Ap layer). The antibody facilitated the gene transfer capability of the DA–Ap layer only to the specific cells that were expressing corresponding antigens. When the DA–Ap layer was fabricated with an anti-N-cadherin antibody, a higher gene transfer capability compared with the D–Ap layer was found in the N-cadherin-positive P19CL6 cells, but not in the N-cadherin-negative UV♀2 cells or in the P19CL6 cells that were pre-blocked with anti-N-cadherin. Therefore, the antigen–antibody binding that takes place at the cell–layer interface should be responsible for the higher gene transfer capability of the DA–Ap than D–Ap layer. These results suggest that the DA–Ap layer works as a mediator in a specific cell-targeted gene transfer system.  相似文献   
999.
Cell morphology has received considerable attention in recent years owing to its possible relationship with cell functions, including proliferation, differentiation, and migration. Recent evidence suggests that extracellular environments can also mediate cell functions, particularly cell adhesion. The aims of this study were to investigate the correlation between osteogenic differentiation activity and the morphology of rat mesenchymal stromal cells (MSCs), and to develop a method of estimating osteogenic differentiation capability of MSCs on biomaterials. We measured the attachment areas of MSCs on substrates with various types of surface after 2 h of seeding, and quantified the amount of osteocalcin secreted from MSCs after 3 weeks of culture under osteogenic differentiation conditions. MSCs with small attachment areas showed a high osteogenic differentiation activity. These findings indicate that cell attachment areas correlate well with the osteogenic differentiation activity of MSCs. They also suggest that the measurement of cell attachment areas is useful for estimating the osteogenic differentiation activity of MSCs and is a practical tool for applications of MSCs in regenerative medicine.  相似文献   
1000.
We present a sandwich liquid-core waveguide for the study of the dynamic extraction of dye molecules by ionic liquid (IL). The incident light was introduced into the core of the IL phase directly via a fused silica prism to form total reflection at the IL/cladding interface. The changes in light intensity and absorbance spectra over time were monitored during the extraction process by maintaining an optical focus on the IL/water interface. The dynamic extraction of the dye Eriochrome Black-T (EBT) by the IL 1-n-butyl-3-methylimidazolium hexafluorophosphate (BmimPF(6)) at different concentrations and various pH conditions was investigated. The results indicated that the accumulation of the dye at the IL/water interface and the dynamic extraction of the dye into the IL phase both contributed to the increase in absorbance. The increased signal along with the increase in pH suggests that electrostatic interaction might be the main driving force for the extraction of EBT by BmimPF(6), and the micro-circumstance provided by IL also has a decisive effect on the characteristics of the spectra recorded by the waveguide system.  相似文献   
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