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81.
Kanai T Sawada T Toyotama A Yamanaka J Kitamura K 《Langmuir : the ACS journal of surfaces and colloids》2007,23(7):3503-3505
The optical stop band in colloidal crystals is characterized by the central frequency and bandwidth. Although the former is known to be highly tunable by changing the lattice constant, the latter is basically determined by the refractive index contrast between the particles and the background medium that is intrinsic to the materials. In this study, we show that the effective bandwidth in gelled colloidal crystals can also be tuned by controlling the fabrication conditions. Single-domain gelled colloidal crystals were prepared by photopolymerization under various photoirradiation conditions. It was observed that the width of the stop band in the transmission or reflectance spectrum could be expanded by simply adjusting the irradiation time. 相似文献
82.
83.
H. Imao M. Tarek K. Michishio Y. Enomoto T. Shimoyama Y. Kanai N. Kuroda A. Mohri H. Higaki H. Saitoh H. A. Torii Y. Nagata H. Toyoda Y. Matsuda Y. Nagashima Y. Yamazaki 《Hyperfine Interactions》2009,194(1-3):71-76
Our group “ASACUSA MUSASHI” has established an efficient way for accumulating antiprotons and extracting them as intense ultra-slow mono-energetic beams at the CERN-AD facility. This novel beam opens new frontiers for investigating a variety of physics. For realizing H? spectroscopy and the test for charge-parity-time symmetry, we have also developed the cusp trap, a combination of an anti-Helmholz superconducting coil and a multi-ring electrode trap, for trapping both antiprotons and positrons and then synthesizing antihydrogens. Recently, the cusp trap was practically used to accumulate antiprotons. The last piece for synthesizing antihydrogens in the cusp trap is the positron accumulator. We have developed a compact system to effectively accumulate positrons based on N2 gas-buffer scheme with a specially designed high precision cylindrical multi-ring electrode trap. The recent progress of the developing work is an important milestone for upcoming antihydrogen science of ASACUSA MUSASHI. 相似文献
84.
K. Kanai T. Nishi T. Iwahashi Y. Ouchi K. Seki Y. Harada S. Shin 《Journal of Electron Spectroscopy and Related Phenomena》2009,174(1-3):110
Electronic structures of ionic liquids formed by 1-buthyl-3-alkylimidazolium ion [Cnmim]+ (n = 4 and 8) with various inorganic and organic anions have been investigated by ultraviolet photoemission, X-ray photoemission, inverse photoemission and soft X-ray emission spectroscopies (SXES). The comparison of the calculated density of states with the observed spectra revealed that the molecular orbital energies of these ionic liquids are significantly affected by the electrostatic Madelung potential among the ions. The SXES results clearly show that the both highest occupied and lowest unoccupied states of [C4mim]+PF6− are derived from the cation as a result of strong Madelung potential. On the other hand, the SXES results show the valence electronic structures of ionic liquids with larger anion molecules, [Cnmim]+Tf2N− and [Cnmim]+OTf− are contributed from the both cation and anion. 相似文献
85.
Naoya Kishikawa Nobuhiro Ohkubo Kaname Ohyama Kenichiro Nakashima Naotaka Kuroda 《Analytical and bioanalytical chemistry》2009,393(4):1337-1343
A sensitive and selective chemiluminescence assay for the determination of quinones was developed. The method was based on
generation of reactive oxygen species through the redox reaction between quinone and dithiothreitol as reductant, and then
the generated reactive oxygen was detected by luminol chemiluminescence. The chemiluminescence was intense, long-lived, and
proportional to quinone concentration. It is concluded that superoxide anion was involved in the proposed chemiluminescence
reaction because the chemiluminescence intensity was decreased only in the presence of superoxide dismutase. Among the tested
quinones, the chemiluminescence was observed from 9,10-phenanthrenequinone, 1,2-naphthoquinone, and 1,4-naphthoquinone, whereas
it was not observed from 9,10-anthraquinone and 1,4-benzoquinone. The chemiluminescence property was greatly different according
to the structure of quinones. The chemiluminescence was also observed for biologically important quinones such as ubiquinone.
Therefore, a simple and rapid assay for ubiquinone in pharmaceutical preparation was developed based on the proposed chemiluminescence
reaction. The detection limit (blank + 3SD) of ubiquinone was 0.05 μM (9 ng/assay) with an analysis time of 30 s per sample.
The developed assay allowed the direct determination of ubiquinone in pharmaceutical preparation without any purification
procedure.
Figure Chemiluminescence generated through the redox cycle of quinone 相似文献
86.
Fukuta Y Mita T Fukuda N Kanai M Shibasaki M 《Journal of the American Chemical Society》2006,128(19):6312-6313
An asymmetric ring-opening reaction of meso-aziridines with TMSN3 was developed using a catalyst prepared from Y(OiPr)3 and chiral ligand 2 in a 1:2 ratio. Excellent enantioselectivity was realized from a wide range of substrates with a practical catalyst loading. The products were efficiently converted to enantiomerically enriched 1,2-diamines, which are versatile chiral building blocks for pharmaceuticals and chiral ligands. This reaction was applied to a catalytic asymmetric synthesis of Tamiflu, a very important anti-influenza drug containing a chiral 1,2-diamino functionality. 相似文献
87.
Uryu T Sugie M Ishida S Konoma S Kato H Katsuraya K Okuyama K Borjihan G Iwashita K Iefuji H 《Applied biochemistry and biotechnology》2006,135(1):15-31
Ethanol was produced in a considerably high yield by fermenting hydrolyzates from cellulosic materials by means of a recombinant
laboratory yeast expressing β-glucosidases. Tissue paper, cotton, and sawdust were hydrolyzed by two-step sulfuric acid hydrolysis
to give mixtures containing glucose, cellobiose, and higher cello-oligosacc arides. After the cellulosic material was partially
hydrolyzed with 80% sulfuric acid, the hydrolysis was continued with 5% sulfuric acid. Except for non-carbohydrate components,
all constitutents in the hydrolyzates were fermented by the yeast that was preincubated in the medium that the plasmid encoded
by the β-glucosidases gene was kept in the muliplicated yeast. A solution containing 4% hydrolyzates from paper was fermented
to give as high as 1.9% maximum ethanol concentration and 70% ethanol conversion. Cotton also gave a similar result. Sawdust
was converted into ethanol in approx 22% conversion. Accordingly, it was revealed that the β-glucosidases-expressing yeast
can ferment the cello-oligosaccharides obtained by hydrolysis of cellulosic materials into ethanol. In addition, a hydrolyzate
containing a high glucose proportion gave a high ethanol concentration in a short time. 相似文献
88.
Masahiro Kanai 《Journal of statistical physics》2014,157(2):282-294
We propose a misanthrope process, defined on a ring, which realizes the totally asymmetric simple exclusion process with open boundaries. In the misanthrope process, particles have no exclusion interaction in contrast to those in the simple exclusion process, while the hop rates depend on both numbers of particles at departure and arrival sites. Arranging the hop rates, we can recover the simple exclusion property and moreover have condensation if the number of particles exceeds that of sites. One condensate grows at an arbitrary single site and then behaves as an external reservoir providing and absorbing particles. It is known that, under some condition, the misanthrope process has an exact solution for the steady-state probability distribution. We exploit this to investigate the present model in an analytical manner. 相似文献
89.
A copper‐catalyzed migratory oxidative‐coupling reaction between nitrones and various ethers/amines exhibited high functional‐group tolerance. Even in aqueous media, the reaction proceeded efficiently. For practical use of this catalysis, a unique sequential Huisgen cycloaddition was demonstrated. Mechanistic investigations revealed that the reaction proceeded through oxidative catalytic activation of ethers/amines to afford iminium/oxonium intermediates by concurrent dual one‐electron abstractions by copper(II) and oxyl radicals. 相似文献
90.
Yasushi Kanai Yoshihiro JinboKazuya Koyama Kazuetsu YoshidaSimon Greaves Hiroaki Muraoka 《Journal of magnetism and magnetic materials》2012,324(3):282-286
Landau-Lifshitz-Gilbert micromagnetic models were used to analyze the head field distributions and high-frequency responses for various soft magnetic underlayer thicknesses (t-SUL) and saturation magnetization flux densities (Bs) of single-pole-type (SPT) head-SUL systems. It was found that Bs of 10-12 kG and t-SUL of 30-45 nm would be sufficient for the examined head and perhaps for most next generation head-SUL systems. Antiferromagnetic coupling in the SUL affects the head and SUL magnetization and, eventually, the head field. With regard to the head magnetization response, it was found that the magnetization under the coil responded first, while the response at the main pole tip was quite slow, even compared with the head field. The main pole tip of the head was fully saturated and the main pole yoke was almost saturated, while the SUL was not saturated in the examined head-SUL system. 相似文献