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991.
Hideo Kaiju Mao NishiyamaYuki Otaka Naoaki SakaguchiKazuo Shiiki 《Journal of magnetism and magnetic materials》2006
The oxidation states of Al-oxide layer and the leakage current density in coercive differential spin tunneling junctions Co/Al-oxide/Co have been investigated in order to clear the mechanism of the increasing resistance change. X-ray photoelectron spectroscopy analysis shows that the resistance change increases with decreasing unoxidized Al, which can be qualitatively explained by using first-principle band calculation based on linear-muffin-tin-orbital atomic-sphere-approximation method. The resistance change decreases with increasing leakage current density, which originates from Schottky effect. Reduction of unoxidized Al and leakage current density originating from Schottky effect is required to obtain the large resistance change in spin tunneling junctions. 相似文献
992.
Bo Yang Hideo Matsumura Kunio Furusawa 《Colloids and surfaces. B, Biointerfaces》1999,14(1-4):161-168
By measuring the change in interfacial tension after adding phospholipid vesicles to an aqueous solution of electrolyte, we studied the adsorption behavior of phospholipid vesicles at oil/water interfaces. The effects of concentration of three kinds of electrolyte (NaCl, MgCl2, LaCl3) and of the mixing ratio of two kinds of phospholipids (phosphatidylcholine and phosphatidylserine), on the adsorption behavior at an oil/water interface were examined. The results were interpreted using the DLVO theory. 相似文献
993.
Takashi Ichinose Hideo Tamura Hiroshi Tamura Valentin A. Zagrebnov 《Communications in Mathematical Physics》2001,221(3):499-510
The norm convergence of the Trotter–Kato product formula is established with ultimate optimal error bound for the selfadjoint semigroup generated by the operator sum of two selfadjoint operators. A generalization is
also given to the operator sum of several selfadjoint operators.
Received: 5 October 2000 / Accepted: 12 March 2001 相似文献
994.
Daisuke Noda Masao Tanabiki Kazuhiro Tsuchiya Yusuke Sunada Hideo Nagashima 《Polyhedron》2009,28(18):3935-3944
A series of azanickellacyclopentene complexes having iodo, bromo, chloro, or triflate ligand on the Ni center were prepared, and are subjected to studies on ethylene polymerization catalysis. Activity of these mononuclear azanickellacyclopentene complexes was increased in the order, Ni–Cl < Ni–I ≈ Ni–Br < Ni–OTf; this is explained by the performance of (pseudo)halogeno ligand as a leaving group from the nickel center. Methylalminoxane (MAO) and inexpensive AlEt2Cl can be used as the cocatalyst. Mechanistic consideration suggested the involvement of neutral Ni-alkyl intermediates as proposed in the SHOP type catalytic system. Interestingly, the catalytic activity is significantly increased by incorporating the second metals into the diimino moiety of mononuclear complex. Two factors should be considered to explain this activity enhancement. One is the increased rigidity of the azanickellacyclopentene ligand backbone, and the other is the possibility of the presence of the two active centers in one molecule. 相似文献
995.
996.
Hideo Fujikake Masashi Kuboki Takeshi Murashige Hiroto Sato Hiroshi Kikuchi Taiichiro Kurita Fumio Sato 《Liquid crystals》2004,31(7):989-992
This paper discusses thermal phase transitions in a nematic liquid crystal material, filling a highly strained porous polyolefin film. Ruptured and aligned polymer fibrils, whose minimum diameter reaches several tens of nm, formed polymer networks in the porous film. From observations of temperature-controlled composite films using a polarizing microscope, it was noted that the isotropic-to-nematic phase transition temperatures of submicron liquid crystal domains, located in or near molecularly aligned streak-like polymer areas, were significantly higher than those located at some distance from these areas. It was assumed that the highly aligned polymer chains in the fine fibrils promote the nematic phase of the liquid crystal. The stretched porous polymer, exhibiting spatial ordering on a submicron scale, is thus suitable for the control of thermal phase transitions in a liquid crystal. 相似文献
997.
Tomohiro Shirosaki Ryota Harisaki Maki Horikawa Hideo Sakurai Shoji Nagaoka 《合成通讯》2014,44(2):275-279
A facile preparation method for derivatization of fullerene through the Bingel reaction was introduced. A series of fullerene derivatives, to which malonic diester with different substituents were introduced, were systematically synthesized by Bingel reaction. Malonic diester could be added to fullerene at room temperature in the presence of iodine and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), and various substituents such as phenyl, hexyl, thienyl, and pyrenyl were introduced into both sides of the malonic diester. As a result, 17 systematic variations were synthesized. The solubility parameters of the obtained fullerene derivatives calculated by the method reported by Fedors were in the range of 33 to 43 (J cm?3)1/2. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
998.
Katsumi Shozugawa Motoyuki Matsuo Yuji Sano Yosuke Toh Yukihiro Murakami Kazuyoshi Furutaka Mitsuo Koizumi Atsushi Kimura Kaoru Hara Tadahiro Kin Masumi Oshima Shoji Nakamura Hideo Harada 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):341-346
Multiple prompt gamma-ray analysis (MPGA), a new radionuclide quantification method with high energy resolution, was applied to sediments from a marine shallow-water hydrothermal mound. Surface sediments around mounds were collected from the Wakamiko submarine crater located in Kagoshima Bay, southwest Japan, where the hydrothermal system was different from those at other marine shallow-water hydrothermal mounds. All samples were desalted and MPGA measurements were performed for 4,500?s (real time). Event data were obtained using eight Canberra-Eurisys CLOVER Ge detectors. The size of the list data that included all multiple events was from 1.19 to 19.2?GB. We could obtain concentrations of 32S, 55Mn, 75As, 157Gd, 39K, 149Sm, 56Fe, and 85Rb with high sensitivity by MPGA. Furthermore, 32S, 85Rb, and 55Mn have characteristic concentrations only at a mound, not at control sampling sites, suggesting that sediments were sulfurated by magmatic fluids at this mound. 相似文献
999.
Hideo Tajima Shoya Morimoto Yuta Yoshida Kazuaki Yamagiwa 《Polymer Science Series A》2012,54(10):787-797
Slow swelling and shrinking rates are a significant challenge for some applications of temperature-sensitive hydrogels. This study reports raspberry-form poly N,N-diethylacrylamide (DEAA) gel particles, which are aggregates of single spherical gel particles. The raspberry-form gel particles show improved temperature-response rates especially for swelling. This improvement in the response rate is attributed to two key factors: the free space between the individual gel particles that make up the aggregated gel particle, and the constraints from the contact points between the individual gel particles. During the swelling process, the polymer chain networks can diffuse at the faster rate characteristic of the individual gel particles constructing the raspberry-form gel, and consequently the response rate of the overall raspberry-form gels can be accelerated. During the shrinking process, the constraints from the contact points between the individual gels dominate the polymer chain diffusion and the shrinking rate because of non-zero shear modulus. The shrinking behavior was affected not by the individual particle size, but rather the apparent gel size and shape. 相似文献
1000.
Atsuo Iida Corresponding author Yumiko Takahashi Yoichi Takanishi Michi Nakata Ken Ishikawa Hideo Takezoe 《Liquid crystals》2013,40(6):717-726
The local layer structure of surface stabilized electroclinic liquid crystals has been analysed by time‐resolved synchrotron X‐ray microdiffraction. At a low applied electric field, the initial bookshelf structure starts to respond above a threshold voltage. With a low to medium applied field of triangular form, the layer structure transforms reversibly between the bookshelf (low field) and the compound chevron (high field), in which the vertical and horizontal chevrons alternate along the layer. When the horizontal chevron component appears, a stripe texture can be seen in an optical micrograph. With increasing field, the horizontal chevron becomes a dominant structure while the vertical chevron still remains. The layer spacing changes in correlation with the chevron angle during the field application. At high field, surface molecules partly rearrange, resulting in alignment deterioration at the interface. The layer response time for an a.c. square wave field is of the order of a few µs to ten µs, which is close to the optical response. The appearance of the compound chevron is discussed in conjunction with the anchoring effect. 相似文献