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81.
Haruhisa Ueda Masahiro Wakisaka Hiromasa Nagase Takeshi Takaha Shigetaka Okada 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):403-405
Cyclomaltooctadecaose(CD18),cyclomaltononadecaose(CD19),cyclomaltoeicosaose(CD20) andcyclomaltoheneicosaose(CD21) are cyclic oligosaccharides composed of 18, 19, 20 and 21 D-glucose units, respectively. This report describes the physicochemical properties of CD18, CD19, CD20 and CD21 in terms of aqueous solubility, surface tension, optical rotation and acid-catalyzed hydrolysis. 相似文献
82.
LiMn2O4 is one of the most promising cathode materials for lithium secondary battery because of natural abundance of manganese in
the crust and its low toxicity to environment. Lithium ion can almost reversibly intercalate into or deintercalate from lithium
manganese spinel oxide LiMn2O4. A part of substitution of manganese with other transition metals brings the improvement of cycle life. We focused on the
local structure of the spinels and considered the effect of the local distortion on the cycle life of the spinel cathodes.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
83.
84.
Ken Okano Hideo Kiyota Tatsuya Iwasaki Yoshitaka Nakamura Yukio Akiba Tateki Kurosu Masamori Iida Terutaro Nakamura 《Applied Physics A: Materials Science & Processing》1990,51(4):344-346
An n-type semiconducting diamond film has been synthesized by the hot filament CVD method using diphosphorus pentaoxide as the doping source. The obtained film was identified as polycrystalline diamond containing few sp2 components by means of several methods including Raman spectroscopy. From measurements of the Hall effect and the Seebeck effect, the film was found to be an n-type semiconductor.Patent pending No. Heisei 1-302209 相似文献
85.
Tanaka H Mori H Seino H Hidai M Mizobe Y Yoshizawa K 《Journal of the American Chemical Society》2008,130(28):9037-9047
The N-N bond activation of the dinitrogen ligand in the cubane-type mixed-metal sulfido cluster, [(Cp*Ir) 3{Ru(tmeda)(N 2)}(mu 3-S) 4] (tmeda = Me 2NCH 2CH 2NMe 2), is investigated by using DFT calculations at the B3LYP level of theory. The elongated N-N bond distance, red-shifted N-N stretching, and negatively charged N 2 ligand indicate that the dinitrogen is reductively activated by complexation. The degree of the N-N bond activation is classified into the "moderately activated" category, [ Studt, F. ; Tuczek, F. J. Comput. Chem. 2006, 27, 1278 ] as in the Mo-triamidoamine complex that can catalyze N 2 reduction [ Yandulov, D. V. ; Schrock, R. R. Science 2003, 301, 76 ]. Availability of the RuIr 3S 4 cluster as a catalyst for N 2 reduction is discussed by optimizing possible intermediates in a catalytic cycle analogous to that proposed by Yandulov and Schrock. A calculated energy profile of the catalytic cycle demonstrates that the RuIr 3S 4 cluster can transform dinitrogen into ammonia in the presence of lutidinium cation and Cp* 2Co as proton and electron sources, respectively. The RuIr 3S 4 clusters with an NNH x ( x = 1-3) ligand, which are intermediates in the catalytic cycle, have a significantly bent Ru-N-N linkage, although precedent NNH x complexes generally adopt a linear M-N-N array. The unique structures of the nitrogenous ligands in these intermediates are interpreted in terms of the bonding interaction between the hydrogen atom bonded to the N 2 ligand and the adjacent iridium atom in the cuboidal RuIr 3S 4 framework. 相似文献
86.
Dr. Katsuhiko Takeuchi Hiro‐omi Taguchi Ippei Tanigawa Shota Tsujimoto Prof. Tsukasa Matsuo Dr. Hiromasa Tanaka Prof. Kazunari Yoshizawa Prof. Fumiyuki Ozawa 《Angewandte Chemie (International ed. in English)》2016,55(49):15347-15350
The Pt0 complex [Pt(PPh3)(Eind2‐BPEP)] with a pyridine‐based PNP‐pincer‐type phosphaalkene ligand (Eind2‐BPEP) has a highly planar geometry around Pt with ∑(Pt)=358.6°. This coordination geometry is very uncommon for formal d10 complexes, and the Pd and Ni homologues with the same ligands adopt distorted tetrahedral geometries. DFT calculations reveal that both the Pt and Pd complexes are M0 species with nearly ten valence electrons on the metals whereas their atomic orbital occupancies are evidently different from one another. The Pt complex has a higher occupancy of the atomic 6s orbital because of strong s–d hybridization due to relativistic effects, thereby adopting a highly planar geometry reflecting the shape and orientation of the partially unoccupied orbital. 相似文献
87.
Phytochrome-mediated inhibition of coleoptile growth in rice: age-dependency and action spectra 总被引:1,自引:0,他引:1
Phytochrome has been shown to be the major photoreceptor involved in the photo-inhibition of coleoptile growth in Japonica-type rice (Oryza sativa L.). We have characterized this typical photomorphogenetic response of rice using mutants deficient in phytochrome A (phyA) and phytochrome B (phyB) and with respect to age-dependency and action spectra. Seedlings were irradiated with a pulse of light 40 h or 80 h after germination (i.e. at an early or late developmental stage) and the final coleoptile length of these seedlings was determined. A saturating pulse of red light (R) had a stronger effect when it was given in the late stage than in the early stage. It was found that the photoinhibition is mediated by both the phyA and the phyB in the late stage but predominantly by phyB in the early stage. Consistent with many other reported responses, the photo-inhibition in the phyA mutant, which was observed in the early and late developmental stages and is thought to be mediated mainly by phyB, occurred in the low-fluence range (10(1)-10(3) micromol m(-2)) of R and was far-red-light (FR)-reversible; the photo-inhibition in the phyB mutant, which was observed in the late developmental stage and is thought to be mediated mainly by phyA, occurred in the very-low-fluence range (10(-2)-10(0) micromol m(-2)) and was FR-irreversible. The action spectra (350-800 nm at 50 nm intervals) obtained at the two developmental stages using phyA and phyB mutants indicated that both the phyB-mediated low-fluence response and the phyA-mediated very-low-fluence response have a major peak at 650 nm and a minor peak at 400 nm. 相似文献
88.
Huo C Su X Li X Zhang X Li C Wang Y Shi Q Kiyota H 《Magnetic resonance in chemistry : MRC》2007,45(6):527-530
A new 2(3 --> 20)abeotaxane with an unusual 13beta-substitution pattern and a new 6/8/6-ring taxane were isolated from the methanol extract of the needles of Taxus cuspidata. The structures were established as 2alpha,7beta-diacetoxy-5alpha,10beta,13beta-trihydroxy-2(3 --> 20)abeotaxa-4(20), 11-dien-9-one (1) and 2alpha,5alpha,7beta,9alpha,13alpha-pentahydroxy-10beta-acetoxytaxa-4(20),11-diene (2) on the basis of 1D and 2D NMR spectral data and high-resolution FAB-MS analyses. 相似文献
89.
Radiochemical neutron activation analysis coupled with the k0-standardization method (k0-RNAA method) was applied to silicate rock samples for the simultaneous determination of trace halogens (Cl, Br and I). Analytical results obtained by the k0-RNAA method for geological standard rocks and meteorite samples agreed with those determined by the conventional comparison method conducted in the same set of experiments, suggesting that the k0-RNAA method is as reliable as the conventional method. Our data for these samples are in good agreement with their literature values except for rare cases. Detection limits calculated under the present experimental condition are sufficiently low for Cl and Br but not for I for typical geologic and meteoritic samples. The k0-RNAA method coupled with longer neutron-irradiation is expected to yield satisfactorily low detection limits for halogens including I in these samples. 相似文献
90.
Acyclic diterpene glycosides, named capsianosides I', II, III (1), C (2), D (3), E (4) and F (5), have been isolated from the dried hot red pepper fruits of Capsicum annuum L. used in Kimchi. The structures of these compounds have been revised in the sugar connectivities by 1D- and 2D-NMR spectroscopic and chemical methods. 相似文献