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991.
A peak considered to be due to disulfoton sulfoxide as a metabolite of disulfoton was detected in the analysis of the chingentsuai extraction solution of vegetables by GC-FPD. In the analysis by GC/MS for identification, though the retention time and the mass spectrum were the same as those of the standard, the spectrum was different from MS library data. It appeared that decomposition of disulfoton sulfoxide occurred at the inlet. Therefore, we used a programmed temperature vaporization (PTV) inlet in the pulsed splitless mode to achieve a low inlet temperature and high injection pressure. As a result, the expected mass spectrum of disulfoton sulfoxide was obtained. Under this condition, the peak obtained from chingentsuai was identified as disulfoton sulfoxide. Disulfoton sulfoxide was detected from 2 of 25 chingentsuai samples, at concentrations of 0.66 microg/g and 0.14 microg/g.  相似文献   
992.
Summary An active transport of alkali metal ion through cation exchange membranes was studied under various conditions. This active transport was facilitated by using a greater anion species on an acidic side in a diaphragm cell, in which one side of the solution was adjusted to be acidic and the other side alkaline across the membrane. An active transport fraction of alkali metal ion was in order poly(styrenesulfonate)>benzenesulfonate>Cl >I>Br of anion species on the acidic side. A rate, fraction and period of the active transport of metal ion were significantly influenced by an electric potential gradient in the membrane.  相似文献   
993.
Phase changes on the surface resulting from low-temperature annealing of yttria-doped tetragonal ZrO2 polycrystals under controlled humidity conditions were investigated at 0.1 to 7350 Pa of water vapor pressure and 100° to 600°C for 1 to 50 h. The tetragonal-to-monoclinic phase transformation was greatly accelerated by increasing water vapor pressure; the transformation rate was first order with respect to the concentration of tetragonal ZrO2 on the surface of the sample.  相似文献   
994.
In this paper, we present evidence that there are two closely linked copies of the ATP3 gene coding for the gamma subunit of the F(1)F(0)-ATPase complex (EC3.6.1.34) in four laboratory strains of Saccharomyces cerevisiae, even though the yeast genome project has reported that ATP3 is a single-copy gene on chromosome II. We previously reported that the gene dosage (three copies) of ATP1 and ATP2 is coincident with the subunit number of F(1)-alpha and F(1)-beta, but that the gene dosage of ATP3 was not consistent with the subunit stoichiometry of F(1)F(0)-ATPase. By applying long PCR and gene walking analyses, we estimated that the two copies of ATP3 were approximately 20 kb apart, and we designated that which is proximal to the centromere ATP3a, while we named that which is distal ATP3b. The nucleotide sequences of the two copies of ATP3 were identical to the reported sequence in the W303-1A, W303-1B and LL20 strains, while only the DC5 strain had a single base substitution in its ATP3a. With the exception of this substitution, the other nucleotide sequences were identical to the upstream 860 bp and the downstream 150 bp. The differences between ATP3 with the single base substitution (Ser(308) to Phe) and ATP3 without the substitution on the complementation of the ATP3 disruptant and on the maintenance of the mitochondrial DNA were observed, suggesting that Atp3ap and Atp3bp in the DC5 strain might have different functions. However, it should not always be necessary for yeast cells to carry different types of ATP3 because the other three strains carry the same type of ATP3. It was also demonstrated that the disruption of the ATP3 genes basically leads to a loss of wild-type mtDNA, but the stability of the mtDNA is not dependent on the ATP3 alone.  相似文献   
995.
We have calculated impact ionization (II) and Auger recombination (AR) lifetimes in hot carrier solar cells (HC-SCs) in operation, and found that these lifetimes are much longer than the average retention times of photo-generated carriers in the cells at an appropriate range of applied voltage, under practical conditions of 500–1000 times-concentrated solar irradiation and carrier thermalization times of several hundred picoseconds. This means that the particle conservation (PC) model, in which II and AR are completely excluded, can be applied to predict the conversion efficiency. In contrast, the PC model does not stand under the ideal condition of the maximally concentrated irradiation and no thermalization of carriers, as previously pointed out.  相似文献   
996.
    
The high-pressure gas (HPG) method with carbon monoxide (CO) and oxygen (O2) mixture maintains the preserved rat heart function. The metabolites of rat hearts preserved using the HPG method (HPG group) and cold storage (CS) method (CS group) by immersion in a stock solution for 24 h were assessed to confirm CO and O2 effects. Lactic acid was significantly lower and citric acid was significantly higher in the HPG group than in the CS group. Moreover, adenosine triphosphate (ATP) levels as well as some pentose phosphate pathway (PPP) metabolites and reduced nicotinamide adenine dinucleotide phosphate (NADPH) were significantly higher in the HPG group than in the CS group. Additionally, reduced glutathione (GSH), which protects cells from oxidative stress, was also significantly higher in the HPG group than in the CS group. These results indicated that each gas, CO and O2, induced the shift from anaerobic to aerobic metabolism, maintaining the energy of ischemic preserved organs, shifting the glucose utilization from glycolysis toward PPP, and reducing oxidative stress. Both CO and O2 in the HPG method have important effects on the ATP supply and decrease oxidative stress for preventing ischemic injury. The HPG method may be useful for clinical application.  相似文献   
997.
998.
    
This report presents rigorous analysis of Arnol'd tongues generated by a manifold piecewise linear circuit. The circuit comprises an LC oscillator, a conductive switch that produces the manifold, and a voltage source controlled by the current value through the inductor when the voltage across the capacitor exceeds a threshold. From the circuit dynamics, the Poincaré return map is explicitly derived as a piecewise linear circle map, and the generation of Arnol'd tongues is precisely explained. We attempt to derive the border–collision bifurcation boundaries of the Arnol'd tongues, some of which are obtained explicitly. Furthermore, we experimentally verify these theoretical results. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
999.
    
Evaporative self‐assembly of polymeric colloids is among the most attractive strategies for the preparation of soft materials with submicrometer‐scale ordered structures. In this study, meniscus splitting from an aqueous solution of liquid crystalline (LC) polysaccharide xanthan gum is verified under conditions of controlled evaporative rate in a limited space. Under fast evaporation rate with a steep gradient of humidity above the air–LC interface, the meniscus splitting is induced to bridge the gap and a vertical membrane with uniaxial orientation is obtained. The process is thermodynamically and polariscopically validated focusing on the ordered polymeric adsorption and the bridging of the millimeter‐scale gap. This clarification will serve not only as a method for immobilization of fluidically ordered structures but also in the control of the evaporative interface for the ordering of polymer solutions into advanced membranes with uniaxial orientation.  相似文献   
1000.
    
Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Additionally, the efficacy of targeted molecular therapies with multiple tyrosine kinase inhibitors is limited. In this study, we focused on the cellular signaling pathways common to diverse HCC cells and used quantitative reverse phase protein array (RPPA) and statistical analyses to elucidate the molecular mechanisms determining its malignancy. We examined the heterogeneity of 17 liver cancer cell lines by performing cluster analysis of their expression of CD90 and EpCAM cancer stem cell markers. Gaussian mixture model clustering identified three dominant clusters: CD90-positive and EpCAM-negative (CD90+), EpCAM-positive and CD90-negative (EpCAM+) and EpCAM-negative and CD90-negative (Neutral). A multivariate analysis by partial least squares revealed that the former two cell populations showed distinct patterns of protein expression and phosphorylation in the EGFR and EphA2 signaling pathways. The CD90+ cells exhibited higher abundance of AKT, EphA2 and its phosphorylated form at Ser897, whereas the EpCAM+ cells exhibited higher abundance of ERK, RSK and its phosphorylated form. This demonstrates that pro-oncogenic, ligand-independent EphA2 signaling plays a dominant role in CD90+ cells with higher motility and metastatic activity than EpCAM+ cells. We also showed that an AKT inhibitor reduced the proliferation and survival of CD90+ cells but did not affect those of EpCAM+ cells. Taken together, our results suggest that AKT activation may be a key pro-oncogenic regulator in HCC.  相似文献   
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