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61.
Adsorption equilibrium data in lumped water quality indices obtained for diluted solutions of a peat water and effluents from a wastewater treatment were analyzed using the ideal adsorbed solution theory with the Freundlich equation. The use of the same value for Freundlich exponent 1∕n in the ideal adsorbed solution theory resulted in a straightforward and less computationally demanding expression to describe an overall batch adsorption isotherm. A fictive component approach, assuming a logarithmic normal distribution of Freundlich K and a nonadsorbable fraction, adequately described and predicted the overall isotherms for different initial concentrations of diluted solutions presented as a lumped water quality index. The parameters in the distributed fictive component approach were independently sensitive to each portion of an isotherm curvature. Preferential adsorption of the smaller molecular weight (MW) components was observed by a size-exclusion high-performance liquid chromatography. Two-dimensional distribution analysis of organics in terms of Freundlich K and MW revealed a weak tendency of the adsorptive strength to decrease with the increase of the MW. 相似文献
62.
Based on the present state of the art of the separation technology, recycling of fission-product rare elements (FRE) in the FBR spent fuel is discussed. The rad.-waste fractionation is in accordance with the present society's trend toward zero-emission, and the mean of salt-free method utilizing electrochemistry agrees with the principles of the newly established green chemistry. A catalytic electrolytic extraction method is proposed to separate the target, radioactive but potentially strategic elements, Pd, Ru, Rh, Re (Tc), Te and Se dissolved in the HLLW. It avoids secondary waste arising. This method is particularly feasible for the separation of Pd where cyclic reaction of metal cations such as Pd(II) or Fe(II), acting as promoters or mediators and already contained in HLLW, accelerates the electrochemical deposition of Ru, Rh and Re. Elemental separation not only offers alternative material resources to meet expanding demands for catalysts in Fuel Cell/Soft Energy system but is also the first step for transmutation or other selective strategies for waste management of long-lived fission products (LLFP). 相似文献
63.
In this work we report the effects of single stage zone drawing on the properties of NEW-TPI thermoplastic polyimide homopolymer, and its blends with Amoco's Xydar liquid crystalline polymer. Zone drawing was performed first on homopolymer NEW-TPI films to determine the effect of load weight, heater speed, and drawing temperature on the attainable draw ratio. Degree of crystallinity and chain orientation increase as the draw ratio increases for NEW-TPI. Blends of NEW-TPI/Xydar compositions 90/10 and 70/30 were studied next. In blends, the Xydar component is not molecularly dispersed, and is initially preferentially oriented along the machine direction during the film processing stage. Xydar acts as a nucleation site and lowers the temperature for crystallization of the NEW-TPI from the rubbery amorphous state. Zone drawing was performed either parallel or perpendicular to Xydar's initial preferred orientation direction. Blends with lower Xydar fraction could be zone-drawn to higher ratios. Zone drawing perpendicular to Xydar's initial orientation direction also resulted in increased draw ratio. Dynamic mechanical properties of the zone drawn materials were studied. In homopolymer NEW-TPI, dynamic modulus increased by a factor of two to 4.0 GPa in zone drawn films, largely as a result of the formation of oriented crystallites. In the blends, the modulus parallel to Xydar's initial orientation direction was greater than that in the transverse direction. Depending upon composition and test direction, zone drawing increased the dynamic moduli of the blends from 1.5 up to 2.7 times, in the temperature range from 150°C to 300°C. 相似文献
64.
65.
Synthesis of non-equilibrium phases in immiscible metals mechanically mixed by high pressure torsion
Tatsuya Miyazaki Daisuke Terada Yoji Miyajima Challapalli Suryanarayana Reiko Murao Yoshihiko Yokoyama Kazumasa Sugiyama Minoru Umemoto Yoshikazu Todaka Nobuhiro Tsuji 《Journal of Materials Science》2011,46(12):4296-4301
The structural changes in mechanically mixed metals of immiscible combinations of elements caused by bulk mechanical alloying
(MA) through the use of high pressure torsion (HPT) were investigated in Ag–Ni and Nb–Zr systems. There was no alloying between
Ag and Ni on atomic scale even after 100 rotations of HPT. On the other hand, the β-Zr phase started to appear after HPT 2
rotations in the Nb–Zr system, even though β-Zr is a high temperature phase. Further, Nb and Zr were completely mixed to form
a bcc structured single phase after HPT 100 rotations. The sequence of alloying in the Nb–Zr system during HPT was discussed.
These results clearly suggest that non-equilibrium phases can form in the Nb–Zr system by bulk MA by the use of HPT. 相似文献
66.
Yoshihiko Shiraki 《应用聚合物科学杂志》2024,141(9):e55010
The development of hydrophobic and oleophobic surfaces on materials has attracted significant attention in various research fields. Fluoropolymers, which possess low surface energy and are both highly hydrophobic and oleophobic in nature, are widely used to enhance the liquid repellency of materials. However, during fluoropolymer manufacture, fluorine-containing compounds are released into the environment; thus, alternatives to fluoropolymers are required for maintaining environmental safety and realizing a sustainable society. Notably, the development of such alternative materials has been limited. Thus, we herein report the application of a novel polyurethane (PU) coating synthesized from bio-based raw materials. The prepared hydrogenated polyfarnesene PU (HHPF PU), which possesses an amorphous bottlebrush-like polyalkyl structure, was found to exhibit higher hydrophobicity and oleophobicity than polytetrafluoroethylene (PTFE), which is a typical low-surface-energy material. The water and n-hexadecane contact angles of the HHPF PU were determined to be 119° and 68°, respectively, whereas those of PTFE were 108° and 46°, respectively. In addition, the density depth profile of the PU thin film was confirmed through x-ray reflectometry. This study provides a novel approach for enhancing the hydrophobicity and oleophobicity of materials using bottlebrush-like polyalkyl structure instead of fluorine. 相似文献
67.
Yoshihiko Nomura Hiroshi Hoshina Hiroshi Shiomi Takao Umezu 《Canadian Metallurgical Quarterly》1985,111(2):138-148
The D301 pipe jacking method is the first to accomplish long spans, curves and high speed construction in the field of small diameter (300 mm) tunneling. The design of the system components are described: tunneling machine with directional control ability, jacking machine, power unit, and control unit which contains a microprocessor. As a result of field tests in about 100 m in length with a 200 curvature radius, the following capabilities are confirmed: the span length is up to 100 m, the curvature radius is down to 200 m, it is useable in either cohesive or sandy soils having N‐curves up to 10, and the construction speed is up to 3 m∕h. 相似文献
68.
Eiji Hiraki Masanobu Yoshida Yoshihiko Hirota Mutsuo Nakaoka 《Electrical Engineering in Japan》2006,157(4):75-84
This paper presents the newly proposed hybrid resonant commutation bridge‐leg link (HRCB) snubber circuit which can achieve zero voltage and zero current soft‐switching commutation for single‐phase and three‐phase voltage source‐type inverter, along with its unique features and operation principle. The circuit parameter design approach for the HRCB snubber circuit and the determination estimating scheme of the gate pulse timing processing which is more suitable and acceptable for single‐phase and space voltage vector modulated three‐phase voltage source inverter using the HRCB snubber circuit are described in this paper. In particular, the three‐phase voltage source soft‐switching inverter associated with the proposed HRCB circuits are evaluated and discussed from simulation and experimental viewpoints. The practical effectiveness of the HRCB snubber‐assisted three‐phase voltage source soft‐switching inverter using IGBT power modules which is based on the instantaneous space voltage vector modulation is clarified on the output voltage waveform, actual efficiency of electromagnetic noise in comparison with three‐phase voltage source‐type conventional hard‐switching inverter. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(4): 75–84, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20111 相似文献
69.
Essence of generalized partial computation 总被引:3,自引:0,他引:3
Generalized partial computation (GPC) is a program optimization principle based on partial computation and theorem proving. Conventional partial computation methods (or partial evaluators) explicitly make use of only given parameter values to partially evaluate programs. However, GPC explicitly utilizes not only given values but also the following information: (1) logical structure of a program to be partially evaluated; (2) abstract data type of a programming language. The main purpose of this paper is to present comprehensible examples of GPC. Graphical notations, called GPC trees, are introduced to visibly describe GPC processes. 相似文献
70.