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81.
Abstract— A new class of ligands for complexation with Ir(III) has been developed. Tris‐homoleptic complexes derived from these ligands have been found to exhibit highly efficient blue phosphorescence with photoluminescent quantum yields in solution at room temperature of >0.9. These complexes have been applied as the emissive materials in OLEDs to give devices with efficiencies of up to 26 cd/A and an E.Q.E. of 1 7.4% at 1 mA/cm2.  相似文献   
82.
High efficiency beam splitter for multifocal multiphoton microscopy   总被引:4,自引:0,他引:4  
In this article we present the development of a multibeam two-photon laser scanning microscope. A new type of beam splitter to create the multitude of laser beams is described. This type of beam splitter has higher transmission and generates more uniform beams than can be achieved with the microlens approach used by other groups. No crosstalk exists between the different foci due to small temporal delays between the individual beams. The importance of dispersion compensation to obtain maximum efficiency of the microscope is discussed. With optimum compensation the fluorescence signal was raised by a factor of 14. Different modes of detecting the fluorescence signals and their effect on imaging speed and resolution are discussed.  相似文献   
83.
No one can deny the importance of mobility in modern communication networks, and the Internet is no exception. The internet engineering taskforce (IETF) has introduced the network mobility (NEMO) protocol to support a moving network. NEMO solves many problems of mobile internet protocol to support a moving group of users but introduces some problems of its own such as suboptimal routing and multiple levels of encapsulation. These problems occur because the NEMO basic support protocol does not support route optimization and nested mobile networks. Many solutions have been proposed in the literature to solve these problems. In this paper, we present a comprehensive survey of those solutions and discuss their advantages and disadvantages. We also outline the effect of these solutions on handovers, and a summary is provided in the form of a table at the end. In this paper, we back up our earlier work with a comprehensive discussion of the protocols included. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
84.
BACKGROUND: To explore the impact of a prevention program on the eating and body attitudes of a sample of adolescent schoolgirls. METHODS: The program involved lessons and group discussions of general adolescent problems and eating disorders. A total of 254 16-year-old schoolgirls were evaluated, of whom 154 participated in the program and a further 154 subjects formed the control group. Variations in weight, Eating Attitudes Test and Eating Disorders Inventory at a 1-year follow-up were compared for the two groups. RESULTS: Among high-risk subjects, no significant differences were found between the prevention and the control group. The preventive program appeared to reduce significantly body dissatisfaction and to decrease the risk of bulimic attitudes in low-risk subjects. CONCLUSIONS: Providing schoolgirls with the correct information about eating disorders did not encourage unhealthy attitudes to eating and weight regulation practices. However, for high-risk subjects more intensive and specific intervention may be required, for which further research is needed.  相似文献   
85.
In the diagnosis of osteoporosis using single energy quantitative CT (SE-QCT) on the axial skeleton, only spongy bone mineral density (BMD) is used at present. Although the density of cortical bone is also determined by most QCT methods, it is not used for evaluation. The objective of this study was to determine the extent to which the cortical bone of the lumbar vertebral bodies accounts for their load-bearing capacity and failure behaviour, and to use this information to suggest improvements in the differential diagnosis of osteoporosis. Investigations were conducted in a clinical, theoretical-numerical and biomechanical-experimental context. Cortical (BMDC) and spongy (BMDS) bone mineral density was measured by SE-QCT/85 kV on 179 patients (68 males, 111 females). These bone densities were matched with the vertebral body fractures previously determined from conventional X-rays. A finite element model was used to study the variation in structural and material parameters of the vertebral body. 19 vertebral bodies that had been removed post-mortem were available for the biomechanical-experimental investigations. Spongy and cortical bone densities were also determined by SE-QCT on these vertebral bodies. Their failure load was then measured in the axial compression test. These investigations show that, in addition to the spongiosa, the cortical shell plays an important role in the load-bearing capacity of the vertebral body. If the spongiosa is weakened due to a loss of BMD, the residual load-bearing capacity of the vertebral bodies is increasingly shouldered by the cortical bone. The lower susceptibility to fracture in men compared with women when spongy bone mineral density is reduced can thus be attributed to the lack of a reduction in cortical bone mineral density. It is recommended that the BMDC also be evaluated in future, especially in the diagnosis of bone mass losses in women, to improve the estimation of the individual fracture risk.  相似文献   
86.
87.
Oxidative stability of liposomes made of (Docosahexaenoic acid) DHA-containing phosphatidylcholine (PC) was examined during preparation and storage. After preparation of the liposomes, the concentration of primary (conjugated dienes) and secondary oxidation products (Thiobarbituric acid-reactive substances, TBARS) were significantly higher compared to the initial value. During cold storage, formation of conjugated dienes and TBARS remained more or less constant in large unilamellar vesicles (LUV), whereas in mulitilamellar vesicles (MLV) they were seen to increase over a period of 21 days. Evaporation of solvent traces from a lipid film should preferably be done under nitrogen as vacuum evaporation was found to increase oxidation of the phospholipid.  相似文献   
88.
To assess the effects of mass transfer and hydrogen pressure on the oil yield and quality from cellulosic biomass, fixed-bed pyrolysis (atmospheric pressure) and hydropyrolysis experiments at temperatures between 400 and 650°C have been conducted on sunflower bagasse and pure cellulose. The Euphorbia Rigida was extracted with n-hexane and methanol to remove low molecular mass terpenoids and saccharides so as to elucidate the extent of oil formation and aromatisation from the cellulosic structure. In contrast to coals and oil shales, oil yields from the sunflower bagasse were found to be largely independent of particle size (<1.8 mm) and sweep gas velocity with ca 35–40% w/w oil (dry basis) being obtained at 450–500°C. The use of high hydrogen pressures (> 50 bar) only gave rise to relatively small increases in oil yield but, expressed on a carbon basis, these increases are much greater due to the reduced the oxygen contents of the oils.  相似文献   
89.
High-throughput file screening against inhibition of human lung PDE4 led to the discovery of 3-ethyl-1-(4-fluorophenyl)-6-phenyl-7-oxo-4, 5,6,7-tetrahydro-1H-pyrazolo[3,4-c]pyridine (11) as a novel PDE4 inhibitor. Subsequent SAR development, using an eosinophil PDE assay, led to analogues up to 50-fold more potent than 11 with IC50 values of 0.03-1.6 microM. One such compound, CP-220,629 (22) (IC50 = 0.44 microM), was efficacious in the guinea pig aerosolized antigen induced airway obstruction assay (ED50 2.0 mg/kg, po) and demonstrated a significant reduction in eosinophil (55%), neutrophil (65%), and IL-1beta (82%) responses to antigen challenge in atopic monkeys (10 mg/kg, po).  相似文献   
90.
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