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101.
The wetting of SiC plate by Y2O3/AlN additive was analysed using the sessile drop method. The wetting behaviour was observed by image capture system using a CCD camera during the heating, in argon atmosphere. The contact angle was measured as a function of temperature and time. After the wetting test the SiC plus additive samples were cut in order to observe the thickness plate cross section. The additive area and the interface between SiC and additive were analysed using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The wetting of SiC by Y2O3/AlN is influenced by the presence of a solid phase in some of the additive drops that depends mainly on the additive composition and consequently on the temperature. The measured contact angles were below 7°, reaching 0° for Y2O3/AlN additive tested at the eutectic composition, indicating a very good wettability of Y2O3/AlN on the SiC.  相似文献   
102.
Diacylglycerol (DAG) is a component of various vegetable oils. Approximately 70% of the DAG in edible oils are in the configuration of 1,3-DAG. We recently showed that long-term ingestion of dietary oil containing mainly 1,3-DAG reduces body fat accumulation in humans as compared to triacylglycerol (TAG) oil with a similar fatty acid composition. As the first step to elucidate the mechanism for this result, we examined the difference in the bioavailabilities of both oils by measuring food energy values and digestibilities in rats. Energy values of the DAG oil and the TAG oil, measured by bomb calorimeter, were 38.9 and 39.6 kJ/g, respectively. Apparent digestibility expressed according to the formula: (absorbed) x (ingested)−1x100=(ingested—excreted in feces)x(ingested)−1x100 for the DAG oil and the TAG oil were 96.3±0.4 and 96.3±0.3% (mean±SEM), respectively. The similarity in the bioavailabilities of both oils supports the hypothesis that the reduced fat accumulation by dietary DAG is caused by the different metabolic fates after the absorption into the gastrointestinal epithelial cells.  相似文献   
103.
We investigated the stress–strain behavior of low molecular weight polycarbonate for optical disc grade (OD‐PC) under carbon dioxide (CO2) at various pressures, and compared the results with that under ambient pressure at various temperatures. Elongation at break decreased sharply with increased CO2 pressure at around 2 MPa, while the elastic modulus decreased gradually up to 6 MPa. These results indicate that the tensile property changed from ductile to brittle with increased CO2 pressure, although the molecular motion is accelerated due to the plasticization effect of CO2. Such ductile‐to‐brittle transition is similar to that observed under elevated temperatures caused by chain disentanglement due to accelerated molecular motion. Although the changes of tensile properties were similar, the craze structure obtained by the brittle behavior was different, i.e., a filamented‐craze structure was obtained under high‐pressure CO2, while a lace‐like one was obtained under elevated temperatures. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers  相似文献   
104.
We have investigated the nanosurface-confined anisotropic growth of ordered-ellipsoidal Fe nanogranules when an Fe plume was deposited at a slanting angle onto an anodized aluminum oxide (AAO) film. Layer-by-layer growth was also investigated. This growth is driven by two critical factors: (1) a new rhombic AAO cell and (2) the slanting deposition of the Fe plume. During slanting deposition, the rhombic AAO cell induces strong restrictions in the nucleation site, growth direction, and granular size; therefore, the degree of freedom during growth is restricted. The magnetic dipoles of the ordered Fe nanogranules are placed along the long axis of the ellipsoid at an angle of 180 degrees (antiparallel) due to the demagnetizing field, shape anisotropy, and magnetic dipole-to-dipole interactions.  相似文献   
105.
We have calculated the characteristics of second- and third-order harmonic distortion in gain-coupled distributed feedback (DFB) lasers using a set of three rate equations. In these calculations, the relaxation oscillation, nonlinear gain compression, and nonlinear loss compression are taken into account. We have found that modulation distortion due to nonlinear gain compression is reduced significantly in the gain-coupled DFB laser of absorptive-grating type. This improvement occurs because gain compression is compensated by loss compression within the grating  相似文献   
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108.
Ferroptosis, a term first proposed in 2012, is iron-dependent, non-apoptotic regulatory cell death induced by erastin. Ferroptosis was originally discovered during synthetic lethal screening for drugs sensitive to RAS mutant cells, and is closely related to synthetic lethality. Ferroptosis sensitizes cancer stem cells and tumors that undergo epithelial−mesenchymal transition and are resistant to anticancer drugs or targeted therapy. Therefore, ferroptosis-inducing molecules are attractive new research targets. In contrast, synthetic lethal strategies approach mechanisms and genetic abnormalities that cannot be directly targeted by conventional therapeutic strategies, such as RAS mutations, hypoxia, and abnormalities in the metabolic environment. They also target the environment and conditions specific to malignant cells, have a low toxicity to normal cells, and can be used in combination with known drugs to produce new ones. However, the concept of synthetic lethality has not been widely adopted with ferroptosis. In this review, we surveyed the literature on ferroptosis-related factors and synthetic lethality to examine the potential therapeutic targets in ferroptosis-related molecules, focusing on factors related to synthetic lethality, discovery methods, clinical application stages, and issues in drug discovery.  相似文献   
109.
Reviewed are the present status and future prospects of the laser fusion research at the ILE Osaka.The Gekko XII and Peta Watt laser system have been operated for investigating the implosion hydrodynamics,fast ignition, and the relativistic laser plasma interactions and so on.In particular,the fast ignition experiments with cone shell target have been in progress as the UK and US-Japan collaboration programs.In the experiments,the imploded high density plasmas are heated by irradiating 500 J level peta-watt laser pulse.The thermal neutron yield is found to increase by three orders of magnitude by injecting the peta-watt laser into the cone shell target.The Rayleigh-Taylor instability experiment results are also reviewed is this paper.  相似文献   
110.
In contrast to the conventional transformation of Bacillus subtilis using purified DNA, those using DNA in lysed protoplasts have a high transformation efficiency and enable whole-genome transfer into competent B. subtilis [Akamatsu, T. and Taguchi, H., Biosci. Biotechnol. Biochem., 65, 823-829 (2001)]. Here, we examined the length of incorporated continuous DNA by analyzing the cotransfer ratio with selected and unselected markers, on the basis of a new experimental design. The cotransfer ratio of a selected marker with an unselected marker on the opposite side of the genetic map of the B. subtilis chromosome was about 5.6% and could be interpreted as congression (double transformation) ratio. In the wild-type strain, the cotransfer ratio of cysA (113 kb position on 4215 kb of B. subtilis chromosome) with metC (1384 kb) and leuB (2891 kb) was 0.77%, twice the value (5.6% x 5.6%=0.31%) calculated from the congression ratio. Moreover, in a genetic background, the cotransfer ratios of metC with cysA and leuB, and metC with cysA and arg1 (3012 kb) were 2.7% and 7.2%, respectively. These results strongly suggest that the length of continuous DNA incorporated into B. subtilis is most probably greater than 1271 kb. When the DNA from the protoplast lysate was fragmented by mixing, the cotransfer ratios of arg1 with metC, and arg1 with metC and trpC (2374 kb) were 2.8% and 0.16%, respectively. A high cotransfer ratio (2.7-7.2%) could not, therefore, be obtained using the fragmented DNA. Based on these observations, we propose a working hypothesis on the mechanism of the transformation of competent B. subtilis by DNA in protoplast lysates (LP transformation).  相似文献   
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