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141.
Yoshimitsu K Nishihara Y Okamoto D Ushijima Y Nishie A Yamaguchi K Taketomi A Honda H 《Magnetic resonance imaging》2012,30(6):854-859
Purpose
The aim of this study is to investigate whether subserosal enhancement on the delayed-phase dynamic magnetic resonance (MR) study (SED) can differentiate T2 from T1 gallbladder carcinoma (GBC).Methods
The institutional research board approved this retrospective study. Between 1997 and 2006, there were surgically proven 11 T1 and 21 T2 GBC in 30 patients, all of whom had undergone preoperative contrast enhanced dynamic MR study, either with a 2D sequence (n=17) or 3D sequences (n=15). All images were reviewed by two radiologists for the presence of SED, and receiver operating characteristic (ROC) curve analysis was performed. Sensitivity, specificity, positive and negative predictive values were calculated by consensus.Results
The areas under the ROC curves of the two readers were 0.91 and 0.86, and the kappa value was 0.78. Of the 21 T2 GBC, 18 and 3 showed positive and negative SED, respectively. Of the 11 T1 GBC, 1 and 10 showed positive and negative SED, respectively. The sensitivity, specificity, positive and negative predictive values of SED for diagnosing T2 lesions were 86%, 88%, 91% and 77%, respectively.Conclusions
In conclusion, SED may be a useful sign to differentiate T2 from T1 GBC, which would affect the preoperative surgical planning of the patients. 相似文献142.
143.
Steric effect in the energy transfer reaction of N(2)(A(3)Σ(u)(+)) + NO(X(2)Π) → NO(A(2)Σ(+)) + N(2)(X(1)Σ(g)(+)) has been studied under crossed beam conditions at a collision energy of ~0.07 eV by using an aligned N(2)(A(3)Σ(u)(+)) beam prepared by a magnetic hexapole. The emission intensity of NO(A(2)Σ(+)) has been measured as a function of the magnetic orientation field direction (i.e., alignment of N(2)(A(3)Σ(u)(+))) in the collision frame. A significant alignment effect on the energy transfer probability is observed. The shape of the steric opacity function turns out to be most reactive at the oblique configuration of N(2)(A(3)Σ(u)(+)) with an orientation angle of γ(v(R)) ~ 45° with respect to the relative velocity vector (v(R)), which has a good correlation with the spatial distribution of the 2pπ(g)* molecular orbital of N(2)(A(3)Σ(u)(+)). We propose the electron exchange mechanism in which the energy transfer probability is dominantly controlled by the orbital overlap between N(2)(2pπ(g)*) and NO(6σ). 相似文献
144.
N. Jaouen J.M. Tonnerre D. Raoux L. Ortega E. Bontempi M. Münzenberg W. Felsch M. Suzuki H. Maruyama H.A. Dürr E. Dudzik G. van der Laan 《Applied Physics A: Materials Science & Processing》2001,72(6):711-715
The element and electronic shell specificities of X-ray resonant magnetic scattering have been used to investigate the magnetization
of Ce 5d and Fe 3d states in [CeH2(19.6 ?)/Fe(25.4 ?)]*38 a multilayer. We show that the measurement of the magnetic contribution to the intensities reflected
at low angles at the Ce L2 and Fe L2,3 edges allows us to investigate the profile of the Ce 5d and Fe 3d magnetic polarization. The Fe 3d polarization is found
to be uniform across the Fe layer and the Ce 5d polarization appears to be restricted close to the interface with Fe.
Received: 22 May 2001 / Accepted: 4 July 2001 / Published online: 5 October 2001 相似文献
145.
E. Arakawa N. Ishimatsu N. Kawamura F. Itoh A. Ochiai H. Maruyama O. Shimomura 《Journal of Physics and Chemistry of Solids》2004,65(12):2089-2092
An experimental system for X-ray magnetic diffraction (XMD) under extreme conditions was constructed on the beamline BL39XU at SPring-8. This system aims at studying magnetic properties of ferromagnets through the measurements of magnetic form factors under the conditions of low temperature (5 K), high magnetic field (6 T) and high pressure (10 GPa). This system consists of a superconducting magnet (SCM), a diamond anvil cell (DAC), a two-axis manipulator for the DAC, a five-axis goniometer for the SCM, and an X-ray polarizer with a phase plate. Details of this system are presented. Experimental results on uranium telluride are shown as a performance test with this instrumentation. 相似文献
146.
Hiroshi Maruyama Masao Shiozaki Sadao Oida Tetsuo Hiraoka 《Tetrahedron letters》1985,26(37):4521-4522
Base treatment of N-propargyl epoxyamide 5 afforded the acetylenic 3-(hydroxyethyl)-2-azetidinone 9a, which was subsequently transformed to phenyl thiolester 2, a versatile intermediate for the carbapenem synthesis. 相似文献
147.
T Niwa W Maruyama D Nakahara N Takeda H Yoshizumi A Tatematsu A Takahashi P Dostert M Naoi T Nagatsu 《Journal of chromatography. A》1992,578(1):109-115
N-Methylsalsolinol, an analogue of 1,2,3,6-tetrahydropyridine, is present in the brains of patients with Parkinson's disease. To determine the metabolic pathway for the synthesis of N-Methylsalsolinol in the brain, salsolinol was perfused through the striatum or the substantia nigra of the rat brain by in vivo microdialysis. N-Methylsalsolinol was detected in the brain dialysate samples during microdialysis with salsolinol using gas chromatography-mass spectrometry with selected-ion monitoring. These results demonstrate that endogenous N-methylation of salsolinol into N-methylsalsolinol occurs in the brain in vivo. 相似文献
148.
T. Arisawa M. Miyabe A. Sugiyama K. Yamazaki A. Ohzu Y. Suzuki K. Akaoka I. Wakaida Y. Maruyama 《Hyperfine Interactions》1997,107(1-4):101-128
The nuclear isomer 178Hfm2, expected to be the most promising candidate for the gamma-ray medium, is rather difficult to produce in large quantities.
There are a few ways to create this isomer, such as the irradiation of 179Hf with high-energy neutrons through the (n,2n) reaction, the irradiation of 176Yb with high-energy α particles through the (α,2n) reaction, the irradiation of 181Ta with protons through the (p,2p2n) reaction. In some of these reaction schemes the isotopically pure target works better
than the natural one from the viewpoint of spectroscopic purity, handling of radioactive materials and productivity. However,
isotope separation of heavy elements for producing a precursor as a target material is difficult in terms of cost/effectiveness.
The atomic vapor laser isotope separation (AVLIS) method is expected as the most efficient way compared with the normal electromagnetic
separation method.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
149.
150.
Kazuhiko Tonooka Norihiko Kamata Koji Yamada Koji Matsumoto Fumio Maruyama 《Journal of Non》1992,150(1-3):185-191
The distribution functions of doped Tb3+ and Nd3+ in silicate, germanate, borate and phosphate glasses, in which cross-relaxation among active ions plays an important role, have been estimated by fluorescence measurements. In order to analyze both the steady state and the transient fluorescence characteristics, a non-linear model for the resonant energy transfer has recently been developed. The experimental fluorescence intensity and decay curves, measured as a function of acceptor concentration, suggested a modified distribution function, which included the effect of the segregation of donors and acceptors. The number of segregated Tb3+ ions at the second nearest neighbor position around a Tb3+ ion was estimated to be 0.1–3.4, depending on the host glass. 相似文献