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To observe the effects of supplemental dietary d-α-tocopherol in relation to dietary energy on growth and immune status in dairy calves, 32 newborn Holstein bull calves were assigned to 1 of 4 treatments for 5 wk in a 2 × 2 factorial, randomized complete block, split-plot design. Calves received moderate growth (MG) or low growth (LG) all-milk dietary treatments, formulated to support daily gains of 0.5 or 0.25 kg/d, respectively, per the dietary energy recommendation for milk-fed calves according to the National Research Council’s Nutrient Requirements of Dairy Cattle. Calves in both groups were either injected i.m. with Vital E-A+D (injectable solution of vitamins E, A, and D) on d 1 and supplemented with Emcelle Tocopherol (micellized vitamin E) via milk daily (MG-S and LG-S), or were not supplemented (MG-C and LG-C) during the study period. Total weight gain of MG calves was greater than that of LG calves and tended to be greater in MG-S calves than in MG-C calves. Calves receiving vitamin supplementation demonstrated greater concentrations of plasma α-tocopherol, retinol, and 25-(OH)-vitamin D than did control calves, whereas MG calves demonstrated a lower concentration of plasma α-tocopherol than did LG calves. The apparent increased utilization of α-tocopherol by MG calves was accompanied by a rise in serum haptoglobin, a positive acute-phase protein and indicator of inflammation, especially in MG-C calves. Serum amyloid A, also a positive acute-phase protein, was not different among groups, but was elevated from baseline in all groups during wk 1 through 3. Plasma IgG1 concentrations were higher in MG-S and LG-S calves than in their nonsupplemented dietary counterparts, whereas plasma IgG2, IgA, and IgM concentrations were not different among groups. In summary, dietary supplementation of d-α-tocopherol improved plasma α-tocopherol status and tended to increase growth in calves fed for 0.5 kg of average daily gain. Vitamin supplementation ameliorated the rise of serum haptoglobin associated with acute inflammation in MG calves, and may have improved passive transfer of maternal antibody. These results indicate a role for α-tocopherol in prevention of proinflammatory state associated with greater dietary energy and onset of infectious disease.  相似文献   
23.
Double duplex invasion (DDI) DNA is a useful antigene method that inhibits expression of genomic DNA. We succeeded in performing photoinduced-DDI (pDDI) using ultrafast photo-cross-linking. 5-Cyanouracil (CNU) has been used in pDDI to inhibit photo-cross-linking between probes, but its importance has not been clarified. Therefore, in this study, we evaluated the effect of spacer (S) and d-spacer (dS) that exhibit photo-cross-linking ability similar to that of CNU. CNU exhibited the highest pDDI efficiency, and S, dS, and T were not very different. The photo-cross-linking inhibitory effect was better with S and dS than with thymidine (T). Conversely, the thermal stability was significantly lower with S and dS than with T. The results suggest that the pDDI efficiency is determined by the balance between the photo-cross-linking inhibitory effect and the thermal stability, which is the introduction efficiency for double-stranded DNA. Therefore, CNU, which has a photo-cross-linking inhibitory effect and a high Tm value, showed the highest inhibitory efficiency.  相似文献   
24.
Optical second-harmonic generation in the Cerenkov-radiation scheme in slab waveguides has been theoretically investigated for all the possible type I configurations. By solving the nonlinear wave equations analytically, a simple general expression for the second-harmonic power has been obtained. Characteristics of the Cerenkov-type second-harmonic generation and optimum conditions for attaining high conversion efficiencies are discussed on the basis of the theoretical analysis. It is shown that, in order to attain high conversion efficiencies, off-diagonal elements of the nonlinear optical coefficient tensor should be utilized taking advantage of birefringence  相似文献   
25.
Electron microscopic observation was made on ZrO2-3 mol % Sm2O3 specimens prepared from the melt using two different cooling rates, namely rapid quenching using a hammer-anvil apparatus and free cooling on a water-cooled copper hearth. The observed microscopic features, such as fully tetragonal grains with parallel twins or herringbone structure, anti-phase boundary contrast in a dark-field image, tweed structure, etc., were found to be quite similar to those observed in similarly prepared ZrO2-3 mol % Y2O3 specimens. It was specifically noted that the tweed structure, which requires atomic diffusion, was not suppressed by the rapid quenching, indicating a very fast growth rate. Trace analysis was also conducted on the tweed structure observed in freely cooled specimens.  相似文献   
26.
Applications of Microsystems in the aerospace create a strong demand in quality control and failure analysis. In this paper, it is shown that high-resolution X-ray diffraction techniques can be used to investigate aging of microelectromechanical systems. This is shown for micromachined silicon actuators for space applications.  相似文献   
27.
Hydration of β-dicalcium silicate was carried out under hydrothermal conditions at different temperatures from 50 °C to 400 °C up to 5 days by using two methods to start the reactions at room temperature or at a desired reaction temperature. 9 C-S-H phases with the same Ca/Si ratio as precursor (γ-dicalcium silicate hydrate and α-dicalcium silicate hydrate and dellaite), Ca-rich compositions (jaffeite and reinhardbraunsite), Si-rich compositions (Ca8Si5O18, kilchoanite and foshagite), and C-S-H gel were obtained at the initial stage of the hydration of β-dicalcium silicate. The reaction products were different in dependence in the hydrothermal processes. It was found that α-dicalcium silicate hydrate was directly formed from β-dicalcium silicate at low temperatures below 220 °C. The products obtained at above 240 °C were different in dependence in the hydrothermal processes, due to the different decomposition route of γ-dicalcium silicate hydrate, the initial product from β-dicalcium silicate. The room temperature mixing method gave reinhardbraunsite and kilchoanite through Ca8Si5O18. In the case of the high temperature mixing method, γ-dicalcium silicate hydrate decomposed to from Ca8Si5O18 and reinhardbraunsite with jaffeite, then Ca8Si5O18 decomposed to from jaffeite and kilchoanite, and final products at 400 °C were reinhardbraunsite and foshagite which was formed from kilchoanite.  相似文献   
28.
Alkaline-earth titanates, MTiO3 (M = Mg, Ca, Sr and Ba), were prepared by solid-state reactions in air and water vapor atmospheres to investigate the effects of water vapor on the formation of MTiO3. The formation of MTiO3 was accelerated more or less by water vapor. Acceleration effect by water vapor increased in the following order: MgTiO3 and CaTiO3 ? SrTiO3 < BaTiO3. The formation of SrTiO3 and BaTiO3 was drastically accelerated by water vapor even though the coarse particles of SrCO3 and BaCO3 remained in the starting mixtures. The difference in its effect might be mainly attributed to the vapor pressure of M(OH)2. Gas-phase transport of M(OH)2 would become important for the formation of MTiO3 by solid-state reactions in water vapor atmosphere.  相似文献   
29.

Abstract  

Solvothermal one-step synthesis method was used for the preparation of ruthenium sulfide catalysts supported on the carbon black by the reaction of Ru3(CO)12 and sulfur powder with the carbon black in i-propanol. The carbon black acted as not only a supporting substrate but also a dispersing agent for ruthenium sulfide nanoparticles in the solvothermal one-step synthesis. The oxygen reduction properties of the products prepared by the solvothermal one-step synthesis were improved in comparison with those of the catalysts prepared by physically mixing the carbon black with the solvothermally prepared ruthenium sulfide powder.  相似文献   
30.
The bisphenol‐F type flexible epoxy resin, having a good flexibility, was combined with an organo‐ and slurry‐clay. The clay dispersions in the obtained epoxy/clay systems are significantly different depending on the type of clay. Particularly, the epoxy/slurry‐clay system showed a high clay dispersibility into the epoxy matrix and was transparent in spite of the addition of 10 wt % clay. This result means that the swelling of the clay with formamide is effective for the expansion of the basal spacing of the clay. The slurry‐clay nanocomposite (clay content: 5 wt %) showed a 4 times higher fracture energy than the neat epoxy system in the tensile test, though the organo‐clay system (clay content: 5 wt %) was 1.5 times higher. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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