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91.
Developments in the continuous galvanizing of steel 总被引:1,自引:0,他引:1
The performance history of galvanized steels, particularly in the automotive industry, has heightened demand for both hot-dip galvanized and electrogalvanized products. Such marketability has led to the commissioning of several new galvanizing lines in recent years. Still, for this timehonored coating process to remain competitive, researchers are investigating methods to improve surface appearance, coating uniformity, corrosion resistance and cost effectiveness. 相似文献
92.
C. Habchi D.T. Nguyen Ph. Barberet S. Incerti Ph. Moretto A. Sakellariou H. Seznec 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):2107-2112
The DISRA (Discrete Image Space Reconstruction Algorithm) reconstruction code, created by A. Sakellariou, was conceived for the ideal case of complete three-dimensional (3D) PIXET (Particle Induced X-ray Emission Tomography) data. This implies two major difficulties for biological samples: first, the long duration of such experiments and second, the subsequent damage that occurs on such fragile specimens. For this reason, the DISRA code was extended at CENBG in order to probe isolated PIXET slices, taking into account the sample structure and mass density provided by 3D STIMT (Scanning Transmission Ion Microscopy Tomography) in the volume of interest. This modified version was tested on a phantom sample and first results on human cancer cells are also presented. 相似文献
93.
94.
Wende H Bernien M Luo J Sorg C Ponpandian N Kurde J Miguel J Piantek M Xu X Eckhold P Kuch W Baberschke K Panchmatia PM Sanyal B Oppeneer PM Eriksson O 《Nature materials》2007,6(7):516-520
To realize molecular spintronic devices, it is important to externally control the magnetization of a molecular magnet. One class of materials particularly promising as building blocks for molecular electronic devices is the paramagnetic porphyrin molecule in contact with a metallic substrate. Here, we study the structural orientation and the magnetic coupling of in-situ-sublimated Fe porphyrin molecules on ferromagnetic Ni and Co films on Cu(100). Our studies involve X-ray absorption spectroscopy and X-ray magnetic circular dichroism experiments. In a combined experimental and computational study we demonstrate that owing to an indirect, superexchange interaction between Fe atoms in the molecules and atoms in the substrate (Co or Ni) the paramagnetic molecules can be made to order ferromagnetically. The Fe magnetic moment can be rotated along directions in plane as well as out of plane by a magnetization reversal of the substrate, thereby opening up an avenue for spin-dependent molecular electronics. 相似文献
95.
T. Y. Hsu X. W. Zhou Ph.D. student 《Metallurgical and Materials Transactions A》1994,25(12):2555-2563
For the possible ordering structures of the parent phase β′—i.e., B2 in Cu-Zn alloys, DO3 in Cu-Al alloys, and B2 and L2, in Cu-Zn-Al alloys—the driving forces for the a, plate formation have been calculated for
the three βCu-base alloys. The driving force, ΔG, is larger than zero for the β′ →α1 shear mechanism and less than zero for the β′ → β′1 + α1 diffusional mechanism. Furthermore, the equilibrium temperature, To, between the parent β′ phase and the α in, plate has been evaluated to be much less than the experimental start temperature,
Bs, of the α1 plate formation. Therefore, the a! plate formation cannot be initiated by a diffusionless β′ → α1 shear reaction without other causative factors such as stress field, defects, etc. However, the α1 plate can be formed through a diffusional β′ → β′1 +α1 reaction. Results in Cu-Al alloys also show that the composition of the α1 plate produced in the diffusional reaction has to deviate from that of the parent phase to a certain extent. For some compositions
of Cu-Zn-Al alloys, ΔGα1(dis.)→α1(ord.) < 0 within a temperature range. Thus, the fresh α1, plate produced after the diffusional reaction may further transform into the ordered α1 plate within this temperature range. Calculated driving forces for the disordered parent phase reveal that the ordering of
the parent phase resists the α1 formation in Cu-Zn and Cu-Zn-Al alloys and enhances it in Cu-Al alloys.
This article is based on a presentation made at the Pacific Rim Conference on the “Roles of Shear and Diffusion in the Formation
of Plate-Shaped Transformation Products,” held December 18–22, 1992, in Kona, Hawaii, under the auspices of ASM INTERNATIONAL’S
Phase Transformations Committee. 相似文献
96.
Analysis of the laser-cladding process for stellite on steel 总被引:2,自引:0,他引:2
A. Frenk M. Vandyoussefi Ph.D. Student J. -D. Wagnière W. Kurz A. Zryd 《Metallurgical and Materials Transactions B》1997,28(3):501-508
Laser-cladding experiments have been performed with STELLITE 6 powder on mild steel substrates, using a 1.5 kW linearly polarized
continuous wave CO2 laser as a heat source. The clad height, the mass efficiency, the dimensions of the melt pool, as well as the global absorptivity,
were measured as functions of the powder feed rate and the scanning speed. A quantitative analytical model of the process
is proposed, based on the overall mass and energy balance. It allows the calculation of the mass efficiency and of the global
absorptivity, taking into account the incorporation of the powder into the melt pool as well as the energy absorbed by the
powder jet and the substrate. It successfully explains the experimental results and demonstrates the role played by the melt
pool inclination with respect to the substrate. A processing diagram is given to find rapidly the optimal laser treatment
conditions and the desired clad height. It is discussed with respect to the other limiting conditions of the process, the
geometrical maximum powder efficiency, the porosity, the dilution, and the maximum power of the laser installation. 相似文献
97.
98.
O.K. Buros Ph.D. 《Desalination》1979,30(1):595-603
Care must be exercised, in predicting operating costs for membrane desalination systems for electricity, labor, chemicals, etc. The assumptions made in establishing unit costs can greatly affect the predicted operating cost and hence the ultimate investment decision. The use of data estimating the quantities of chemicals, power, etc., expected to be used per unit of production can assist in predicting costs, as then site-specific cost data can be used. The fact that 0.2 pounds of acid per kgal of permeate is required in a Florida RO plant is more useful for predicting operating costs of an RO plant on the Island of Anegata than is the fact that acid costs at the Florida plant are $0.03/kgal of water produced. Data based on units rather than costs are presented for seven RO facilities and one ED facility in this paper for use in this type of analysis. 相似文献
99.
Julian Szekely Ph.D. John Busch Ph.D. Gerardo Trapaga Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1996,48(12):43-47
Recent developments in modeling can eliminate much experimental laboratory work and can provide quick answers in a more cost-effective manner. This article presents a brief outline of technical cost modeling, a combination of physical modeling and cost modeling, which may be used to the mutual benefit of both the managerial decision makers and the R&D community within the materials processing field. 相似文献
100.
ZHANGPeng DUYunhui LIUHanwu ZENGDaben BALimin 《武汉理工大学学报(材料科学英文版)》2005,20(1):25-29
The bonding of solid steel plate to liquid aluminum was studied using rapid solidification. The relationship models of interfacial shear strength and thickness of interfacial layer of bonding plate vs bonding parameters ( such as preheat temperature of steel plate, temperature of aluminum liquid and bonding time ) were respectively established by artificial neural networks perfectly. The bonding parameters for the largest interfacial shear strength were optimized with genetic algorithm successfully. They are 226℃ for preheating temperature of steel plate, 723℃ for temperature of aluminum liquid and 15.8s for bonding time, and the largest interfacial shear strength of bonding plate is 71.6MPa. Under these conditions, the corresponding reasonable thickness of interfacial layer (10.8μm) is gotten using the relationship model established by artificial neural networks. 相似文献