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1.
A laser-induced fluorescence microscopic system based on optical parametric oscillation has been constructed as a tunable detector for microchip analysis. The detection limit of sulforhodamine B (Ex. 520 nm, Em. 570 nm) was 0.2 mol, which was approximately eight orders of magnitude better than with a conventional fluorophotometer. The system was applied to the determination of fluorescence-labeled DNA (Ex. 494 nm, Em. 519 nm) in a microchannel and the detection limit reached a single molecule. These results showed the feasibility of this system as a highly sensitive and tunable fluorescence detector for microchip analysis. 相似文献
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Sol-Gel Processing of Transparent PLZT((Pb,La)(Zr,Ti)O3) Fibers 总被引:1,自引:0,他引:1
Kitaoka Kenji Takahara Koji Kozuka Hiromitsu Yoko Toshinobu 《Journal of Sol-Gel Science and Technology》1999,16(1-2):183-193
PLZT((Pb,La)(Zr,Ti)O3) ceramic fibers were prepared by the sol-gel method from a solution of lead acetate trihydrate, lanthanum isopropoxide, zirconium n-propoxide and titanium isopropoxide containing 2-methoxyethanol as the solvent. The as-drawn gel fibers were pretreated in an autoclave and preheated in flowing H2O vapor prior to the heat-treatment for crystallization. The effects of autoclaving and preheating in flowing H2O vapor on the structure and composition of the resultant fibers were investigated. Optically transparent single phase perovskite PLZT fibers of 5–15 m in thickness and 5 cm in length were successfully prepared when the autoclave-treatment and the preheating in flowing H2O vapor were conducted prior to crystallization. These treatments are thought to promote hydrolysis of the organic groups and polycondensation reaction in the gel fibers, leading to the successful formation of dense, crack-free transparent PLZT fibers. 相似文献
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Hayakawa K Ando K Yoshida N Yamamoto A Matsunaga A Nishimura M Kitaoka M Matsui K 《Biomedical chromatography : BMC》2000,14(2):72-76
A high-performance liquid chromatographic method has been developed for the determination of saccharides in sake, an alcoholic beverage brewed from rice. Saccharides in sake were separated on a normal phase (carbamoyl bonded silica) column using a linear gradient elution of water in acetonitrile. Seven saccharides, glucose, maltose, isomaltose, maltotriose, panose, isomaltotriose and ethyl alpha-D-glucoside, were determined by a polarized photometric detector. Unidentified peaks suggesting saccharides with polymerization degrees over 4 were also observed. The proposed method did not require any sample clean-up treatment. As an application, saccharide compositions in various kinds of sake were compared. 相似文献
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Kazumi Ohya Hiroaki Kitaoka Yasuhiko Yotsui Mitsuji Sano 《Journal of mass spectrometry : JMS》1983,18(4):139-146
The mechanism of the pyrolysis reaction of carpronium chloride [(CH3)3N+? (CH2)3? COOCH3CI?] leading to γ-butyrolactone and tetramethylammonium chloride was investigated by means of thermal analysis, pyrolysis gas chromatography mass spectrometry and field desorption mass spectrometry, using deuterium labelling. The results indicated that carpronium chloride pyrolysed to yield equimolar amounts of γ-butyrolactone and tetramethylammonium chloride, methyl transfer occurred between N and O during the pyrolysis process. The mechanism is discussed on the basis of the experimental results, and with the aid of the theoretical results calculated by the CNDO/2 method. The mechanism presented is as follows. γ-Butyrolactone is formed by the intramolecular migration of the π-orbital of C?O to the carbon adjacent to [(CH3)3N]+ via a 5-membered ring transition state, accompanied by a bimolecular reaction between [(CH3)3N]+ and the CH3 of O? CH3, resulting in the formation of tetramethylammonium chloride in an amount equimolar with γ-butyrolactone. 相似文献
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We report the spin Knight shift (K(s)) and the nuclear spin-lattice relaxation rate (1/T1) in the vortex state as a function of magnetic field (H) up to 28 T in the high-Tc superconductor TlSr2CaCu2O6.8 (Tc = 68 K). At low temperatures well below Tc, both K(s) and 1/T1 measured around the middle point between the two nearest vortices (saddle point) increase substantially with increasing field, which indicate that the quasiparticle states with an ungapped spectrum are extended outside the vortex cores in a d-wave superconductor. The density of states (DOS) around the saddle point is found to be kappaN(0)square root[H/H(c2)], with kappa = 0.5-0.7 and N0 being the normal-state DOS. 相似文献
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Ishida K Ozaki D Kamatsuka T Tou H Kyogaku M Kitaoka Y Tateiwa N Sato NK Aso N Geibel C Steglich F 《Physical review letters》2002,89(3):037002
We report (27)Al Knight shift ( (27)K) measurement on a single-crystal UNi(2)Al(3) that reveals a coexistence of superconductivity and a spin-density-wave (SDW) type of magnetic ordering ( T(SDW) = 4.5 K). The spin part of (27)K, (27)K(s), does not change down to 50 mK across the superconducting (SC) transition temperature T(c) approximately 0.9 K. In contrast with the isostructural compound UPd(2)Al(3) ( T(c) approximately 2 K), which was identified to be a spin-singlet d-wave superconductor, the behavior of (27)K strongly supports that UNi(2)Al(3) , like UPt(3) and Sr(2)RuO(4), belongs to a class of spin-triplet SC pairing state superconductors. 相似文献
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Yogi M Kitaoka Y Hashimoto S Yasuda T Settai R Matsuda TD Haga Y Onuki Y Rogl P Bauer E 《Physical review letters》2004,93(2):027003
We report on novel antiferromagnetic (AFM) and superconducting (SC) properties of noncentrosymmetric CePt3Si through measurements of the 195Pt nuclear spin-lattice relaxation rate 1/T(1). In the normal state, the temperature (T) dependence of 1/T(1) unraveled the existence of low-lying levels in crystal-electric-field multiplets and the formation of a heavy-fermion (HF) state. The coexistence of AFM and SC phases that emerge at T(N)=2.2 K and T(c)=0.75 K, respectively, takes place on a microscopic level. CePt3Si is the first HF superconductor that reveals a peak in 1/T(1) just below T(c) and, additionally, does not follow the T3 law that used to be reported for most unconventional HF superconductors. We remark that this unexpected SC characteristic may be related to the lack of an inversion center in its crystal structure. 相似文献
10.
A new NO(2) measurement collection device developed in this study indicates efficient absorption, enough to be applied to the practical determination of atmospheric NO(2), which should become a useful tool compared with conventional methods. 相似文献