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181.
Itoh R Onuki Y Abe K Abe K Adachi I Aihara H Asano Y Aushev T Bakich AM Ban Y Barberio E Bay A Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Dash M Dong LY Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Gorisek A Haba J Hara K Hara T Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T 《Physical review letters》2005,95(9):091601
CP violation in B-->J/PsiK* decays is studied using an angular analysis in a data sample of 253 fb(-1) recorded with the Belle detector at the KEKB e(+)e(-) collider. The flavor separated measurements of the decay amplitudes indicate no evidence for direct CP violation. T-odd CP violation is studied using the asymmetries in triple product correlations, and the results are consistent with the standard model null predictions. The time-dependent angular analysis gives the following values of CP-violating parameters: sin(2phi(1) = 0.24 +/- 0.31 +/- 0.05 and cos(2phi(1)=0.56 +/- 0.79 +/- 0.11. 相似文献
182.
Izawa K Kasahara Y Matsuda Y Behnia K Yasuda T Settai R Onuki Y 《Physical review letters》2005,94(19):197002
The superconducting gap structure of recently discovered heavy fermion CePt(3)Si without spatial inversion symmetry was investigated by thermal transport measurements down to 40 mK. In zero field a residual T-linear term was clearly resolved as T --> 0, with a magnitude in good agreement with the value expected for a residual normal fluid with a nodal gap structure, together with a T2 dependence at high temperatures. With an applied magnetic field, the thermal conductivity grows rapidly, in dramatic contrast to fully gapped superconductors, and exhibits one-parameter scaling with T/sqrt[H]. These results place an important constraint on the order parameter symmetry; that is, CePt(3)Si is most likely to have line nodes. 相似文献
183.
Superconducting gap structure of spin-triplet superconductor Sr2RuO4 studied by thermal conductivity
Izawa K Takahashi H Yamaguchi H Matsuda Y Suzuki M Sasaki T Fukase T Yoshida Y Settai R Onuki Y 《Physical review letters》2001,86(12):2653-2656
To clarify the superconducting gap structure of the spin-triplet superconductor Sr2RuO4, the in-plane thermal conductivity has been measured as a function of relative orientations of the thermal flow, the crystal axes, and a magnetic field rotating within the 2D RuO2 planes. The in-plane variation of the thermal conductivity is incompatible with any model with line nodes vertical to the 2D planes and indicates the existence of horizontal nodes. These results place strong constraints on models that attempt to explain the mechanism of the triplet superconductivity. 相似文献
184.
Akira Onuki 《Physics letters. A》1979,70(1):31-33
A steady state of a two-dimensional incompressible fluid with shear flow is considered. The nonlinear (non-newtonian) shear viscosity is obtained and the correlation of velocity field fluctuations is found to become long-ranged. 相似文献
185.
Beck JL Gupta R Urathamakul T Williamson NL Sheil MM Aldrich-Wright JR Ralph SF 《Chemical communications (Cambridge, England)》2003,(5):626-627
ESI mass spectra show that up to five ruthenium molecules can bind non-covalently to double stranded 16mer DNA, and provide information on the relative affinity and DNA sequence selectivity of different ruthenium complexes. 相似文献
186.
187.
Hiroaki Imai Koichi Awazu Masarux Yasumori Hideo Onuki Hiroshi Hirashima 《Journal of Sol-Gel Science and Technology》1997,8(1-3):365-369
Structural changes in SiO2 and TiO2 gel films were investigated using ultraviolet (UV) and vacuum ultraviolet (VUV) irradiations. A significant compaction with dehydration of SiO2 gel films was induced by irradiation of photons in the range of 9–18 eV. The refractive index and the shrinkage of the irradiated SiO2 gel films were comparable to those obtained by sintering at 1000°C. Densification of TiO2 gel films was also observed with irradiation of 5–14 eV photons. However, effects of the irradiation on TiO2 gel were smaller that those on SiO2 gel. The structural changes in the gel films are attributed to electronic excitations which are induced by irradiation with photons having higher energies than the bandgap of the oxides. The photo-induced effects are presumed to depend on the optical properties and structure of the gels. 相似文献
188.
New and higher yielding synthetic routes to N-protected N-methylpyrrole and N-methylimidazole amino acids are introduced to circumvent difficulties associated with established schemes. Key steps in each synthesis include copper-mediated cross-coupling reaction to directly install a carbamate-protected 4-amine in the N-methylpyrrole derivative and effective nitration followed by a one-pot reduction/Boc protection of the amine in the synthesis of the N-Me-imidazole amino acid. 相似文献
189.
Brodie CR Collins JG Aldrich-Wright JR 《Dalton transactions (Cambridge, England : 2003)》2004,(8):1145-1152
This study documents the first detailed investigation into the relationship between molecular structure and biological activity of platinum(II) complexes containing methylated derivatives of 1,10-phenanthroline (phen). A series of square planar platinum(II) compounds incorporating methylated derivatives of phen, 4-methyl-1,10-phenanthroline (4-Mephen), 5-methyl-1,10-phenanthroline (5-Mephen), 4,7-dimethyl-1,10-phenanthroline (4,7-Me2phen), 5,6-dimethyl-1,10-phenanthroline (5,6-Me2phen) and 3,4,7,8-tetramethyl-1,10-phenanthroline (3,4,7,8-Me4phen) were synthesised and the relationship between their structure and biological activity investigated. The biological activity of these compounds was quantified using the in vitro cytotoxicity assay against the L1210 Murine leukaemia cell line. Large variation in cytotoxicities with different methylation was observed. The 5- and 5,6-methylated derivatives of phen displayed a greater biological activity, with IC50 values of 2.8 +/- 0.8 microM and 1.5 +/- 0.3 microM respectively, compared with the phen compound, with an IC50 value of 9.7 +/- 0.3 microM, while all the others were inactive with IC50 values over 50 microM. Binding constants were determined using circular dichroism spectroscopy (CD) and induced circular dichroism (ICD). ICD was used to highlight any differences in the spectra. Viscometry studies and linear dichroism (LD) experiments indicate that the platinum(II) complexes intercalate although for [Pt(en)(4-Mephen)]Cl2 and [Pt(en)(4,7-Me2phen)]Cl2 this mode of binding appears to be concentration dependent. The binding of the platinum(II) complexes to the oligonucleotide d(GTCGAC)2 was studied using two-dimensional 1H NMR spectroscopy. The addition of each metal complex to the hexamer d(GTCGAC)2 produced upfield shifts of the metal complex resonances, characteristic of intercalation. Through the observation of NOE cross-peaks, two-dimensional NMR studies provided insight into the site and groove preferences of these compounds when binding to DNA. 相似文献
190.
Janice Tardiff Ralph M. Deal William L. Hase Da-hong Lu 《Journal of Cluster Science》1990,1(4):335-354
Classical trajectory simulations are used to study the intramolecular dynamics of isolated CF3H and the CF3H(H2O)3 cluster, by either exciting the CH stretch local mode to then=6 level or by adding an equivalent amount of energy to an OH stretch normal mode. Energy transfer from the CH local mode is statistically the same for CF3H(H2O)3 as for isolated CF3H, and agrees with previous experimental studies. Clusters excited with 6 quanta in the CH local mode are remarkably stable. Though the CF3H-(H2O)3 intermolecular potential is only 1.5 kcal/mol, only 1 of 26 clusters excited with 6 quanta in the CH local mode dissociate within 10 ps. The absorption linewidth for the CH local mode in CF3H(H2O)3 is related to IVR within CF3H and not to the unimolecular lifetime of the cluster. When an OH stretch normal mode of the cluster is excited, energy transfer to CF3H is negligible and nearly one half of the clusters dissociate within 10 ps. 相似文献