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1.
Kenzo Kitayama 《Journal of the American Ceramic Society》1992,75(6):1447-1451
Phase equilibria in the Ta-Co-O and Nb-Co-O systems have been studied at 1200°C at oxygen partial pressures from 10−0.68 to 10−13.50 atm for the former and from 10−0.68 to 10−13.30 atm for the latter. In both systems, M2 CoO6 and M2 Co4 O9 are stable ternary compounds under the experimental conditions, and a new phase, Nb5 Co2 O14 , has been identified. The Ta-Co-O system is simple, whereas the Nb-Co-O system is somewhat more complicated because of the extra phase. The lattice constants of the ternary compounds have been determined and compared with previous values. The standard Gibbs energies of reactions have been determined using oxygen partial pressures in equilibrium with three solid phases. 相似文献
2.
We observed change in distance between two droplets in each step after application of large multi-step shear strains. Experiments were performed using a sliding plate apparatus. Large step shear strains were applied to two polyisobutylene droplets in poly(dimethyl siloxane) matrix in the same plane between the plates. The distance between the two droplets decreases with increasing the total shear strain, which is given by the product of the step strain magnitude and the number of application of the step strains. The two droplets coalesce when the distance becomes less than the diameter of the droplets. The slope for plots of the distance versus the total strain is independent of the step strain magnitude. This indicates that the effect per unit strain on the distance is the same, irrespective of the strain magnitude. It is suggested that a stronger hydrodynamic interaction between the droplets is the main cause for the droplet approach. 相似文献
3.
S Murakami I Yamagishi Y Asami M Sato K Tomisawa 《Canadian Metallurgical Quarterly》1996,42(6):865-872
The effects of a novel acyl-CoA: cholesterol acyltransferase (ACAT) inhibitor, HL-004, on cholesterol metabolism were examined in mice peritoneal macrophages. Cholesteryl ester-rich foam cells were induced by incubating macrophages with acetylated LDL. HL-004 prevented the accumulation of cholesteryl ester in the presence of the cholesterol acceptor, HDL. In the absence of HDL, HL-004 generated large amounts of free cholesterol in the cell. Moreover, HL-004 stimulated the efflux of cholesterol from preestablished foam cells in the presence of HDL. These results suggest that the inhibition of foam cell formation and the stimulation of foam cell regression by HL-004 are attributed to intracellular ACAT inhibition, and that HL-004 would be expected to exhibit an antiatherosclerotic effect through direct action on arterial wall. 相似文献
4.
Hiromasa Higasa Ryoichi Takahata Hiroshi Imaizumi Kenzo Miya 《Electrical Engineering in Japan》1996,116(3):96-106
A high-temperature superconductor YBa2Cu3O7-x with strong pinning force has allowed stable magnetic suspension with no control to be developed. Two types of superconducting magnetic bearings (SMB) using YBCO and permanent magnet were assembled. The two types are radial and axial. The dynamic stiffness of each SMB as it was cooled down under a magnetic field by liquid nitrogen was measured both radially and axially. As a result, it was found that the spring constants of these SMBs were almost as large as a practically desirable value; however, their damping coefficients were lower than the practical level. These findings are useful as one of the data bases for development of an optimum SMB design to support the weight of rotors in an axial direction. 相似文献
5.
6.
The UV-stabilizing ability and thermal loss from the polystyrene film of novel UV absorbers, 2-[(3-hydroxy-4-benzoyl) phenoxy] pentachlorocyclotriphosphazene (HBPC) and hexakis[ (2-hydroxy-4-benzoyl) phenoxy] cyclotriphosphazene (HBPP), were investigated. The UV-stabilizing ability of HBPC estimated by the formation of carbonyl groups in polystyrene was comparable to that of 2,4-dihydroxybenzophenone (DHB), suggesting that the phosphazene moiety does not affect the efficiency of the stabilizing ability of DHB units. No significant difference of efficiency per stabilizing units between HBPC and HBPP was observed. HBPC and HBPP are noteworthy for their low thermal losses from the polystyrene film, i.e., the thermal loss of HBPP was completely suppressed and the diffusion coefficient of HBPC at 160°C was two orders of magnitude smaller than that of DHB. The thermogravimetric analysis and differential scanning calorimetry measurement showed that HBPC and HBPP are nonvolatile and stable up to 230 and 300°C, respectively. © 1993 John Wiley & Sons, Inc. 相似文献
7.
Compared 2 motivational bases for not contributing to a public good, desire to "free ride" (or greed) and fear of being a "sucker," among 110 Japanese undergraduates. It was hypothesized that these 2 types of motivation would be activated under different situations. When a public good was provided conjunctively, fear would have a strong effect but greed would not; when a public good was disjunctively provided, greed would have a strong effect but fear would not. In addition, it was predicted that the greater mutual trust existing among friends would make them contribute more than strangers would in the conjunctive condition but would make no difference in the disjunctive condition. Three types of production rules, in which a public good was conjunctively, disjunctively, or additively produced on the basis of members' contributions, were experimentally created. Half of the groups in each condition consisted of total strangers, and the other half consisted of friends. The hypotheses were supported when the size of the public good (bonus points) was relatively large. Also, Ss responded similarly in the conjunctive condition and in the additive condition. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Annadanam V. Sesha Sainath Takashi Inoue Yoshiharu Hatakeyama Masahiro Shishido Kenzo Okamoto Seigou Kawaguchi Takashi Kuriyama Kiyohito Koyama 《大分子材料与工程》2004,289(3):264-268
Summary: Polyacrylonitrile (PAN) particles with micro‐size ranges (0.15–2 μm) were prepared by emulsion and dispersion polymerizationa and in supercritical carbon dioxide media. The PAN particles were blended with Nylon 6 (PA6) at 220 °C by using a miniature mixer; it was found that melt‐mixing was possible for PAN‐rich compositions as high as 70 wt.‐%. Blends were characterized by scanning electron microscopy, IR, viscosity measurements, differential scanning calorimetry, and dynamic mechanical thermal analysis (DMTA). The size and shape of original PAN particles were retained in PAN/PA6 blends. The useful range to blend PAN particles size was less than 1 μm in terms of shape retention of the PAN particles in blends. Blends with 40 wt.‐% PAN content were found to be melt‐processable. The elastic modulus was higher for PAN/PA6 blends than pure PA6.
9.
Saburo Komori Mitsuo Okahara Kenzo Okamoto 《Journal of the American Oil Chemists' Society》1960,37(10):468-473
Summary Since the long-chain fatty acid sucrose diesters inevitably produced in the synthesis of monoesters are only slightly soluble
in water, no important use can be found for them at the present time except as oilsoluble emulsifying agents.
In order to exploit new uses we have attempted to improve their solubility in water by introducing oxyethylene radicals into
the molecule.
The addition reaction of ethylene oxide with the sucrose diesters was carried out in an autoclave in the presence of alkaline
catalysts. With the reaction temperature maintained between 100–130° the pressure decreased as the reaction proceeded, and
one to two hours were required to consume the ethylene oxide used.
The addition products are yellow or orange oily materials soluble in water. Aqueous solutions showed good surface-active properties. 相似文献
10.
Kenichi Yokoyama Toshio Ogawa Kenzo Asaoka Junichi Sakai 《Journal of Alloys and Compounds》2005,400(1-2):227-233
The hydrogen absorption properties of Ti–0.2 mass% Pd (Ti–0.2Pd) alloy in 2.0% and 0.2% acidulated phosphate fluoride (APF) and neutral 2.0% NaF solutions (25 °C) has been evaluated by hydrogen thermal desorption analysis. During the early stage of immersion (120 h) in the 2.0% APF solution, the amount of absorbed hydrogen was lower than 500 mass ppm. A thermal desorption of hydrogen primary appearing with a peak at 500–600 °C and a broad desorption ranging from 100 to 400 °C were observed. In the 0.2% APF solution, the amount of absorbed hydrogen saturated at 100–200 mass ppm; the thermal desorption of hydrogen appeared with a single peak at 550 °C. In the 2.0% NaF solution, hydrogen absorption was negligible even after 1000 h of immersion, although corrosion pits were observed. The results of the present study suggest that the hydrogen absorption of Ti–0.2Pd alloy, as compared with commercial pure titanium, is suppressed in fluoride solutions. 相似文献