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101.
Hiroyuki Ito Toru Sakurai Takekiyo Matsuo Toshio Ichihara Itsuo Katakuse 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):102-104
Mass spectra of doubly charged mercury clusters (m/z=30-1065) were investigated by secondary ion mass spectrometry. Positively charged ions were generated from an amalgam of mercury and silver by bombardment with a xenon ion beam and mass analysis by a grand-scale sector type mass spectrometer. Hg n 2+, n=1-10 and Hg n +, n =1- 5 were observed. Some doubly charged mercury clusters, (Hg n 2+) survived at least for 0.1 ms. 相似文献
102.
Cassette dosing approach and quantitative structure-pharmacokinetic relationship study of antifungal N-myristoyltransferase inhibitors 总被引:1,自引:0,他引:1
103.
Yoshinori Tominaga Yuichi Ichihara Tomoko Mori Chizuko Kamio Akira Hosomi 《Journal of heterocyclic chemistry》1990,27(2):263-268
The reaction of pyridinium or isoquinolinium N-ylides with methoxy-substituted ethylenes gave the corresponding indolizine and pyrrolo[2,1-a]isoquinoline derivatives bearing acetyl, aroyl, cyano, ester group at the 1-position in one step. Pyrazolo[1,5-a]pyridine, pyrazolo[1,5-a]quinoline, and pyrazolo[5,1-a]isoquinolines were also synthesized in good yields from the corresponding aromatic N-imines and methoxyethylene derivatives. 相似文献
104.
Absolute configuration of (?)-solanapyrone A was confirmed by the application of CD exciton chirality method to the dibenzoate derivative. 相似文献
105.
By means of powder X-ray diffraction, powder neutron diffraction and transmission electron microscopy (TEM), we determined the crystal structures of a metal-ordered manganite YBaMn2O6 which undergoes successive phase transitions. A high-temperature metallic phase (Tc1=520 K<T) crystallizes in a triclinic P1 with the following unit cell: Z=2, a=5.4948(15) Å, b=5.4920(14) Å, c=7.7174(4) Å, α=89.804(20)°, β=90.173(20)°, γ=91.160(4)°. The MnO6 octahedral tilting is approximately written as a0b−c−, leading to a significant structural anisotropy within the ab plane. The structure for Tc2<T<Tc1 is a monoclinic P2 (Z=2, a=5.5181(4) Å, b=5.5142(4) Å, c=7.6443(3) Å, β=90.267(4)°) with an a−b−c− tilting. The structural features suggest a dx2−y2 orbital ordering (OO). Below Tc2=480 K, crystallographically inequivalent two octahedra show distinct volume difference, due to the Mn3+/Mn4+ charge ordering. The TEM study furthermore revealed a unique d3x2−r2/d3y2−r2 OO with a modified CE structure. It was found that the obtained crystal structures are strongly correlated to the unusual physical properties. In particular, the extremely high temperature at which charge degree of freedom freezes, Tc2, should be caused by the absence of the structural disorder and by heavily distorted MnO6 octahedra. 相似文献
106.
Fukuda Y Hayakawa T Inoue K Kasuga S Koshio Y Kumita T Matsumoto K Nakahata M Nakamura K Okumura K Sakai A Shiozawa M Suzuki J Suzuki Y Tomoeda T Totsuka Y Hirata KS Kihara K Oyama Y Koshiba M Nishijima K Horiuchi T Fujita K Hatakeyama S Koga M Maruyama T Suzuki A Mori M Kajimura T Suda T Suzuki AT Ishizuka T Miyano K Okazawa H Hara T Nagashima Y Takita M Yamaguchi T Hayato Y Kaneyuki K Suzuki T Takeuchi Y Tanimori T Tasaka S Ichihara E Miyamoto S Nishikawa K 《Physical review letters》1996,77(9):1683-1686
107.
H. Okuyama S. Ichihara Hiroyuki Kato J. Yoshinobu Maki Kawai 《Chemical physics letters》1999,310(5-6)
The symmetry of low-coverage (0.1 ML) ethylene adsorbed on Pd(110) and the co-adsorption effect of hydrogen have been investigated by high-resolution electron energy-loss spectroscopy. Ethylene adsorbs with π-bond character intact on both clean and H-covered Pd(110) with characteristic C–C stretching vibrational energies at 178 and 186 meV, respectively. The symmetry of the adsorbed ethylene, however, drastically changes upon the co-adsorption of hydrogen: the C–C axis which is tilted to the clean Pd(110) surface (C1 symmetry) is rearranged such that it becomes parallel to the H-covered Pd(110) surface (C2 symmetry). 相似文献
108.
The asymmetric synthesis of the highly functionalized (3R,5R,6R)-3,6-diamino-5-hydroxyheptanoic acid, the key amino acid fragment of sperabillins B and D, was achieved by an asymmetric Michael addition of lithium (R)-(-methylbenzyl)allylamide 10 to (E,E)-2,5-heptadienoate establishing the C-3 stereogenic centre, the information from which was propagated to the C-5 and C-6 centres by a highly stereoselective iodocyclocarbamation reaction. 相似文献
109.