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101.
Shizuo Arichi Noriyuki Sakamoto Shozo Himuro Mayumi Miki Masafumi Yoshida 《Polymer》1985,26(8):1175-1180
In order to obtain the additional data concerning the unperturbed dimension of poly-4-substituted styrene, light scattering measurements are performed on the twenty-two fractions with molecular weight of (0.91–352)·104 of poly(4-acetoxystyrene) in dioxan at 25°C, from which the molecular weight obtained was found easily to be evaluated with the gel permeation chromatography using THF. Phase separation experiments for this polymer indicate that the theta state is attained in isopropyl acetate at 19.7°C and butyl acetate at 26.8°C. By making viscosity measurements at that state, the value of KΘ is directly evaluated as 5.4·10?4 dl g?1. The limiting viscosity number is also obtained in good solvents, THF and dioxan, at 25°C and constants of the Mark-Houwink-Sakurada equation in each solvent are determined. Further, approximately the same KΘ as above is obtained from these data with the Stockmayer-Fixman plot. The calculated value of steric factor, 2.37, on this polymer may be plausible, compared with those of polyvinylaromatic derivatives. 相似文献
102.
T. Itoh K. Yoshida T. Yatsu T. Tamura T. Matsumoto G. F. Spencer 《Journal of the American Oil Chemists' Society》1981,58(4):545-550
Nine Spanish olive oils, including three each of virgin (pressed oil), refined virgin, and B-residue (solvent-extracted pomace
oil) oils from different commercial sources, have been analyzed for their unsaponifiable matter (USM). Four sterolic fractions
separated from the oils have been analyzed by preparative thin-layer chromatography (TLC); these fractions are triterpene
alcohols, 4-methylsterols, sterols and triterpene dialcohols. The compositions of the four sterolic fractions were determined
as their acetates by gas-liquid chromatography (GLC) on an OV-17 glass capillary column. Identification of each component
was carried out by argentation TLC, GLC and combined gas chromatography-mass spectrometry (GC-MS); 44 components were identified,
of which four: 24-methylene-31-nor-9(11)-lanostenol, 24-methyl-31-nor-E-23-dehydrocycloartanol, 24-ethyl-E-23-dehydrolophenol
and 5,E-23-stigmastadienol, were considered to be new sterols from natural sources. Several characteristics, including the
content of triteterpene dialcohols in the USM and that of C-24(28) unsaturated sterols in each of the four sterolic fractions,
which can be used to distinguish between virgin and B-residue olive oils, were observed. 相似文献
103.
Fiber volume plays a critical role in achieving stable mechanical and physical properties in composite structures. This study develops a method to control this parameter in carbon fiber reinforced plastics (CFRPs) on the basis of the viscoelastic character of the thermosetting matrix resin. This method relies on the loss angle δ to quantitatively control fiber volume. CFRP flat panels are manufactured at varying initiating times of pressure application depending on the δ value of the CFRP matrix resin. An analysis of the manufactured panels clearly shows that the target fiber volumes can be obtained at an appropriate δ range. Specifically, CFRP fiber volumes can be controlled through the loss angle of the matrix resin. Defining this δ range is very important for establishing mechanically and physically stable CFRP structures. POLYM. COMPOS., 37:1307–1311, 2016. © 2014 Society of Plastics Engineers 相似文献
104.
Kikuo Wakino Tsutomu Okada Norio Yoshida Kunisaburo Tomono 《Journal of the American Ceramic Society》1993,76(10):2588-2594
The dielectric constant of a compound consisting of two different materials was simulated using the Monte Carlo and finite element methods. In the high concentration range of the higher dielectric constant material, the simulated value of the dielectric constant showed a "parallel-model"-like tendency. On the other hand, in the low concentration range of the higher dielectric constant material, the compound showed a "serial-model"-like behavior. Around 65% content of the higher dielectric constant material, it exhibited results similar to the logarithmic mixing rule. After careful consideration of these results, a new equation to predict the dielectric constant of the compound was derived. The agreement between the dielectric constant calculated by the new equation and the measured values was better than in any other case reported before. 相似文献
105.
Beverley M. Dancy Dr. Nicholas T. Crump Daniel J. Peterson Dr. Chandrani Mukherjee Dr. Erin M. Bowers Dr. Young‐Hoon Ahn Dr. Minoru Yoshida Dr. Jin Zhang Dr. Louis C. Mahadevan Dr. David J. Meyers Dr. Jef D. Boeke Dr. Philip A. Cole 《Chembiochem : a European journal of chemical biology》2012,13(14):1973-1973
106.
107.
Yutaka Shinoda Michiyuki Yoshida Takashi Akatsu Fumihiro Wakai 《Journal of the American Ceramic Society》2004,87(10):1919-1926
The deformation behavior of boron- and carbon-doped β-silicon carbide (B,C-SiC) with an average grain size of 260 ± 18 nm containing 1 wt% boron was investigated by compression testing at elevated temperatures. Extensive grain growth during deformation was observed. The stress–strain curves were compensated for grain growth by assuming power-law type of dependence on grain size and strain rate. The stress exponent n was ∼1.3 and the grain size exponent p was ∼2.7 at temperatures ranging from 1593° to 1758°C. The apparent activation energy of deformation Q d was ∼760 kJ/mol, which was lower than the activation energy for lattice diffusion of silicon and carbon in SiC and higher than that for grain-boundary diffusion of carbon in SiC. These results suggest that the deformation mechanism of the fine-grained B,C-SiC is grain-boundary sliding accommodated by the grain-boundary diffusion. 相似文献
108.
Hiromi Nabeshi Tomoaki Yoshikawa Akihiro Arimori Tokuyuki Yoshida Saeko Tochigi Toshiro Hirai Takanori Akase Kazuya Nagano Yasuhiro Abe Haruhiko Kamada Shin-ichi Tsunoda Norio Itoh Yasuo Yoshioka Yasuo Tsutsumi 《Nanoscale research letters》2011,6(1):1-6
In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out. 相似文献
109.
Lu S Ji L He W Dai P Yang H Arimochi M Yoshida H Uchida S Ikeda M 《Nanoscale research letters》2011,6(1):576
We report the initial results of GaAs and GaInP solar cells grown by all solid-state molecular-beam-epitaxy (MBE) technique. For GaAs single-junction solar cell, with the application of AlInP as the window layer and GaInP as the back surface field layer, the photovoltaic conversion efficiency of 26% at one sun concentration and air mass 1.5 global (AM1.5G) is realized. The efficiency of 16.4% is also reached for GaInP solar cell. Our results demonstrate that the MBE-grown phosphide-contained III-V compound semiconductor solar cell can be quite comparable to the metal-organic-chemical-vapor-deposition-grown high-efficiency solar cell. 相似文献
110.