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51.
The techniques for fabricating a hollow optical fiber with an inner silver layer and a cyclic olefin polymer (COP) layer have been improved to reduce the surface roughness of these two layers. The loss spectrum was thereby drastically reduced over a wide wavelength range, from visible to near infrared. Optimization of the COP layer thickness resulted in low loss simultaneously at several key laser wavelengths. Infrared hollow fiber with low loss was developed for Er:YAG and Nd:YAG lasers. It can also deliver green and red pilot beams with low loss. Use of this fiber in therapeutic and pilot lasers should prove useful for research and development in laser medicine. 相似文献
52.
X. J. Liu I. Ohnuma R. Kainuma K. Ishida 《Journal of Phase Equilibria and Diffusion》1999,20(1):45-56
A thermodynamic calculation of the Al-Mn binary system that takes into account recent experimental results and includes five
intermetallic compounds and all the solid-solution phases is presented. The Gibbs energy of the body-centered cubic (bcc)
phase has been described on the basis of the two-sublattice model that includes the second-order A2/B2 ordering reaction as well. A consistent set of optimized thermodynamic parameters has been arrived at for describing the
Gibbs energy of each phase in this system leading to a better fit between calculation and experiments. 相似文献
53.
K. Ishikawa K. Aoki Y. Himuro I. Ohnuma R. Kainuma K. Ishida 《Journal of Phase Equilibria》2001,22(3):219-226
Phase equilibria of 900, 1000, and 1100 °C in the Co-Ti portion of the Co-Al-Ti system were mainly determined by energy dispersion x-ray spectroscopy. On the Ti-Al side, the β-Ti (A2) phase region is extended by the addition of Co and the β-Ti + AlTi3 (D019) two-phase region appears in the ternary equilibrium, while the AlTi (L10), AlTi3, and β-Ti phases show very low solubility of Co. It was found that the two ternary intermetallic compounds, Co2AlTi (L21) and CoAl2Ti (D8 a ), exist over a wide solubility range along the CoAl(B2)-CoTi (B2) and CoAl3-CoTi3 sections, respectively. The ordering transition and the phase separation due to ordering of the β-Ti, CoAl, or CoTi and Co2AlTi phases fundamentally possessing the bcc structure are also discussed. 相似文献
54.
Harumi Yokokawa Natsuko Sakai Teruhisa Horita Katsuhiko Yamaji Yueping Xiong Takanori Otake Hiroo Yugami Tatsuya Kawada Junichiro Mizusaki 《Journal of Phase Equilibria》2001,22(3):331-338
Phase diagram calculations that were made previously for the ZrO2-MO m/2 (m = 2, 3, 4) systems and for the ZrO2-YO1.5-MO m/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic conductivity as a function of oxygen potential, and (3) a miscibility gap observed in air. The interaction parameters for the CeO2-CeO1.5-YO1.5 system were obtained from the reported oxygen nonstoichiometry in CeO2−x and rate earth doped ceria, (Ce,RE)O2−δ . The interaction parameters for the ZrO2-CeO2 subsystem were obtained so as to reproduce the observed miscibility gap at 1273 K. Those thermodynamic properties can reproduce consistently the experimental behaviors of the electronic conductivity and the TG results in the (Zr1−x Ce x )0.8Y0.2O1.9 solid solutions; these indicate the enhancement of reduction of CeO2. 相似文献
55.
56.
Takanori Sone Hirokazu Akagi Hisao Watarai 《Journal of the American Ceramic Society》1991,74(12):3151-3153
Pore behavior as influenced by migration of an abnormal grain boundary was studied. The pore behavior during the discontinuous growth of hot-pressed spinel (MgAl2 O4 ) — whether the pore can move attached to the grain boundary — is particularly governed by the pore size and the matrix grain size. These phenomena can be understood from the interaction between the pore and the abnormal grain boundary. 相似文献
57.
C. P. Wang X. J. Liu R. Kainuma Y. Takaku I. Ohnuma K. Ishida 《Metallurgical and Materials Transactions A》2004,35(4):1243-1253
The effects of alloying elements on the macroscopic morphologies in Cu-Fe base alloys were experimentally investigated. It
was found that macroscopic homogeneity can be achieved by the addition of Mn, Ni, Al, or Co in the Cu-Fe base alloys, while
the core-type macroscopic morphologies with Cu-rich or Fe-rich cores, which are radially separated as two layers in the inner
and outer parts of the ingot solidified in the cast-iron mold, were formed by the addition of C, Cr, Mo, Nb, Si, or V. It
is shown that the formation of the core-type macroscopic morphology is strongly connected with the existence of a stable miscibility
gap of the liquid phase in the Cu-Fe base alloy due to the addition of alloying elements. The liquid phase with less volume
fraction always forms the center part. This result can be explained by a mechanism that the minor droplets as the second phase
are forced to move into the thermal center due to Marangoni motion, which is caused by the temperature dependence of interfacial
energy between two liquid phases. 相似文献
58.
Yukifami Saheki Kenji Negoro Takanori Sasaki 《Journal of the American Oil Chemists' Society》1986,63(7):927-930
New anionic surfactants 2-alkyloyl-1,4,3,6-dianhydrosorbitol-5-sulfates were synthesized by sulfation of 2-alkyloyl-1,4,3,6-dianhydrosorbitol.
Studies on the surface active properties such as surface tension, dispersibility and emulsifiability of these surfactants
were carried out. The results showed these surfactants are better dispersants and emulsifiers than Span 80 and Span 85. 相似文献
59.
Voids are representative of the damage process in both creep and ductile fractures. Although the matrix/precipitate interface
has been considered the preferential nucleation site for voids, the relationship between the atomic structure of this interface
and the nucleation mechanism of a void has never been sufficiently investigated. In this study, the bcc Fe/V4C3 interface is selected as a model interface between a matrix and precipitate. The vacancy formation energy and intrinsic mechanical
strength at this interface are investigated using a first-principles calculation because they should be related with the nucleation
of creep and ductile voids, respectively. Within the considered interface, the Fe vacancy is found to be dominant. When the
Baker–Nutting orientation relationship is satisfied at the interface, the calculated intrinsic mechanical strength of the
interface is 23.8 GPa. However, when the geometric coherence at the interface is low as compared to that of the Baker–Nutting
orientation relationship, it is found that the interfacial mechanical strength is significantly weakened. At each interface,
it is found that the back-bond of the interface determined the interfacial strength because of the strongly bonded Fe–C on
the interface. The nucleation mechanism of a void at the matrix/precipitate interface is discussed based on the present findings.
It is suggested that local decohesion at the matrix/precipitate interface should be the origin of the nucleation of a ductile
void. 相似文献
60.
Takanori Sugawara Massimo Sarotto Alexey Stankovskiy Gert Van den Eynde 《Annals of Nuclear Energy》2011
The XT-ADS, an accelerator-driven system for an experimental demonstration, has been investigated in the framework of IP EUROTRANS FP6 project. In this study, the sensitivity and uncertainty analyses were performed to comprehend the reliability of the XT-ADS neutronic design. 相似文献