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91.
M Asano K Kaneoka T Nomura K Asano H Sone K Tsurumaru K Yamashita K Matsuo H Suzuki Y Okuda 《Canadian Metallurgical Quarterly》1998,162(4):455-459
Atlantoaxial transarticular fixation is a proven stabilization technique used to augment conventional sublaminar fusion. Along with its superior biomechanical profile comes the inherent risk of neurovascular injury and potential compromised fixation during its application. This article presents a detailed systematic guide to this procedure including preoperative evaluation, positioning, and the more subtle aspects of the surgical technique. A new instrumentation design that has enhanced the ease and accuracy of screw placement with less operative frustration and potential morbidity of previous systems also is presented. 相似文献
92.
S Asano 《Canadian Metallurgical Quarterly》1997,117(7):379-393
H+, K(+)-ATPase is a proton pump responsible for gastric acid secretion. It actively transport proton and K+ coupled with the hydrolysis of ATP, resulting in the formulation of a 10(6) fold proton gradient across the plasma membrane of parietal cells. The pump belongs to a family of P-type ATPases which include the Na+ pump (Na+, K(+)-ATPase) and the Ca2+ pump (Ca(2+)-ATPase). This review focuses on the structure-function relationship of this proton pump by using functional antibodies, specific inhibitor(s), a fluorescent reagent and site-directed mutants. First we prepared monoclonal antibodies which modified the functions of the H+, K(+)-ATPase . One of the antibodies, HK2032 inhibited the H+, K(+)-ATPase activity and the chloride conductance in gastric vesicles opened by S-S cross-linking, suggesting that the chloride pathway is in the H+, K(+)-ATPase molecule, and that the H+, K(+)-ATPase is a multi-functional molecule. Other antibody, HK4001 inhibited the H+, K(+)-ATPase activity by inhibiting its phosphorylation step. By using this antibody we found an H+, K(+)-ATPase isoform in the rabbit distal colon. Second we found that scopadulcic acid B, a main ingredient of Paraguayan traditional herb, is an inhibitor specific for the H+, K(+)-ATPase. This compound inhibited the H+, K(+)-ATPase activity by stabilizing the K(+)-form of the enzyme. Third we studied the conformational changes of the H+, K(+)-ATPase by observing the fluorescence of FITC-labeled enzyme. H+, K(+)-ATPase did not utilize acetylphosphate instead the ATP as an energy source of active transport, suggesting that the energy transduction system is not common among P-type ATPases. Finally we constructed a functional expression system of the H+, K(+)-ATPase in human kidney cells. By using this functional expression system in combination with site-directed mutagenesis, we studied the significance of amino acid residues in the catalytic centers (a phosphorylation site and an ATP binding site) and the putative cation binding sites. We newly found the sites determining the affinity for cations. 相似文献
93.
The vaporization of Li4TiO4 has been studied by a mass spectrometric Knudsen effusion method in the temperature range 1082–1582 K. Identified vapors are Li(g), LiO(g), Li2O(g) and Li3O(g). When the vaporization proceeds, the content of Li2O in the Li4TiO4 sample decreases and the condensed phase of the sample changes to β-Li4TiO4 plus l-Li2TiO3 below 1323 K, to β-Li4TiO4 plus h-Li2TiO3 in the range 1323–1473 K and to h-Li2TiO3 plus liquid above 1473 K. On the basis of the partial pressure data, the enthalpies of formation for β-Li4TiO4 from elements and from constituent oxides have been determined to be ΔHf,298°(β-Li4TiO4,s) = −2247.8 ± 14.3 kJ mol−1 and Δfox,298°(β-Li4TiO4, s) = −107.3 ± 14.3 kJ mol−1, respectively. 相似文献
94.
H Hidaka M Asano S Iwadare I Matsumoto T Totsuka N Aoki 《Canadian Metallurgical Quarterly》1978,207(1):8-15
The relaxing effect and possible mechanism of N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) on isolated rabbit artery were investigated. The addition of W-7 in concentrations ranging from 1 X 10(-6) to 3 X 10(-4) M caused a significant relaxation of isolated rabbit vascular strips contracted by KCl, prostaglandin F2alpha, norepinephrine, histamine, CaCl2, serotonin or angiotensin II. W-7 also caused a shift to the right of the dose-response curves for all agonists tested. Propranolol and atropine did not affect W-7 induced relaxation, suggesting that this drug does not act through beta adrenergic or cholinergic receptors. Superprecipitation of actomyosin from bovine aorta smooth muscle was inhibited by the addition of W-7 in a dose-dependent fashion. The concentration of W-7 which inhibited superprecipitation of bovine aorta smooth muscle actomyosin was in good agreement with the dose producing relaxation of isolated vascular strips. These facts suggest that W-7 produces relaxation of isolated vascular strips by inhibiting actin and myosin interaction. 相似文献
95.
S. Obata H. Asano O. Sakurada M. Hashiba Y. Nurishi 《Journal of Materials Science》2005,40(3):757-760
Tetramethyl ammonium hydroxide (TMAOH) has no fluidizing effect on carbon particles, because of their hydrophobic surface properties. On the other hand, styrene/maleic copolymer (SM) enhanced the fluidity of two kinds of carbon slurries in the basic pH range, where the particle diameters of carbon {#}2650 and MA100 were 13 and 22 nm, respectively. High-density sintered bodies of silicon carbide containing carbon and boron carbide as sintering aids were obtained by controlling the pH of 10–11 with TMAOH and by addition of SM: i.e., 9.5 and 5.5 wt% of SM were added to #2650 and MA100, respectively, in the dry weight base of the carbon. The highest sintered density product with more than 98% was obtained by intimate dispersion of the finer carbon particles in the silicon carbide slurries. 相似文献
96.
The availability of the neutrons due to photonuclear reactions has been discussed by using synchrotron radiation with the beryllium targets. The superconducting wiggler with the magnetic field of approximately 10 T, which is installed into an 8 GeV class storage ring, can emit intense and high-energy photons to produce neutrons. By using MCNPX, the simulations were performed for the conceptual design of the neutron beamline to estimate the available intensity and to investigate the shield conditions. The results were discussed in comparison with other research reactors. 相似文献
97.
98.
The mechanical properties of an Al-6 wt pct Zn-1.2 wt pct Mg alloy with various width of precipitate-free zones have been investigated. The width of the precipitate-free zone (PFZ) has been changed by the quench interruption technique without any appreciable change in the size and distribution of precipitates. An important relationship has been observed between the width of the PFZ and the quench-interruption period;i.e., the width of the PFZ increases in proportion to the square root of the holding time at 200°C. From the analysis of stress-strain curves as well as the observation of dislocation arrangements in slightly deformed specimens, the plastic deformation has been found to occur preferentially in the PFZ. The initial stage of deformation is much affected by the change in the width of the PFZ, but in the later stage, the work-hardening rate seems to be almost independent of the PFZ width. Tensile tests show that the ultimate tensile strength and the 0.2 pct proof stress decrease very little with increasing width of the PFZ, while the uniform elongation is practically constant regardless of the reduction in the nonuniform elongation. The work-hardening rate at the initial stage of deformation is found to decrease in proportion to the reciprocal of the PFZ width. This relationship can be explained from the dislocation model for work hardening. 相似文献
99.
100.
The vaporization of Li2SiO3(c/1) has been studied by the mass spectrometric Knudsen effusion method. The vaporization process has been found to be incongruent. Partial pressures of Li(g), LiO(g), Li2O(g), SiO(g) and Li2SiO3(g) over Li2SiO3(c/1) have been determined in the temperature range 1166–1762 K. Partial pressures of O2(g) have also been calculated from the reaction Li2SiO3(1) = 2 Li(g) + SiO(g) + O2(g). The enthalpies of formation and the atomization energies for LiO(g) and Li2O(g) have been evaluated from the partial pressures to be ΔHof0(LiO,g) = (84.5 ± 12.8)kJ/mol, ΔHof0(Li2O, g) = (?148.1 ± 15.8)kJ/mol, D0o(LiO) = (321.4 ± 12.8)kJ/mol and D0o(Li2O) = (713.2 ± 15.8)kJ/mol, respectively. The value of D0o(Li2O) is somewhat greater than twice that of D0o(LiO). 相似文献