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101.
Alexei A. Belik Naoaki Hayashi Masaki Azuma Shigetoshi Muranaka Mikio Takano Eiji Takayama-Muromachi 《Journal of solid state chemistry》2007,180(12):3401-3407
57Fe Mössbauer spectroscopy, dc and ac magnetization, specific heat, and differential scanning calorimetry measurements were performed in a powder BiMn0.95Fe0.05O3 sample prepared at 6 GPa and 1383 K. The substitution of 5% Fe for Mn increases the temperatures of the structural monoclinic-to-orthorhombic phase transition (from 768 to 779 K) and the ferromagnetic transition (from 98 to 109 K) by about 10 K in BiMn0.95Fe0.05O3 compared with BiMnO3. On the other hand, the temperature of the monoclinic-to-monoclinic phase transition associated with the orbital ordering strongly decreases in BiMn0.95Fe0.05O3 (414 K) compared with that of BiMnO3 (474 K). The saturated magnetic moment at 5 K and 5 T is also suppressed from 3.92 μB per formula unit in BiMnO3 to 3.35 μB in BiMn0.95Fe0.05O3. The large quadrupole splitting (1.18 mm/s) observed at 293 K in BiMn0.95Fe0.05O3 can be explained by the strong Jahn-Teller distortion and cooperative orbital order. The quadrupole splitting reduces by two times above the orbital melting temperature. 相似文献
102.
Handling large DNA molecules, such as chromosomal DNA, has become necessary due to recent developments in genome science. However, large DNA molecules are fragile and easily broken by shear stress accompanying flow in solution. This fragility causes difficulties in the preparation and handling of large DNA molecules. This study demonstrates the transition of DNA from a coiled to a globular form, which is highly condensed. This state suppresses DNA fragmentation due to shear stress in solution. The transition enables large DNA molecules to undergo mechanical manipulation. We confirmed that the fluorescence intensity of stained globular DNA increases with increasing length, suggesting that the resistance of globular DNA to shear stress is the factor that allows analysis of large DNA by flow cytometry. 相似文献
103.
Junko Masuda Hiroshi Kawamoto Warren Strober Eiji Takayama Akifumi Mizutani Hiroshi Murakami Tomokatsu Ikawa Atsushi Kitani Narumi Maeno Tsukasa Shigehiro Ayano Satoh Akimasa Seno Vaidyanath Arun Tomonari Kasai Ivan J. Fuss Yoshimoto Katsura Masaharu Seno 《Applied biochemistry and biotechnology》2016,180(8):1559-1573
104.
Takeshi Katsura 《Acta Appl Math》2009,108(3):617-624
In this short paper, we give an explanation of the fact that the Cuntz-Krieger algebras depend only on the one-sided Markov
chains, using topological graphs and factor maps between them. 相似文献
105.
Ichiro Okura Yuichi Kinumi Naruhiko Kaji Shigetoshi Aono 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10-11):1275-1283
Viologen-linked water-soluble porphyrins with different methylene chain lengths between porphyrin and viologen were synthesized. These compounds were applied to photoinduced hydrogen evolution in a system containing NADPH, viologen-linked porphyrin, and hydrogenase under steady-state irradiation. 相似文献
106.
107.
108.
The triple ligand transfer reaction between planar-chiral cyclopentadienyl-ruthenium complexes [Cp′Ru(NCMe)3][PF6] (1) (Cp′ = 1-(COOR2)-2-Me-4-R1C5H2; R1 = Me, Ph, t-Bu) and iron complexes CpFe(CO)(L)X (2) (L = PMe3, PMe2Ph, PMePh2, PPh3; X = I, Br) resulted in the formation of metal-centered chiral ruthenium complexes Cp′Ru(CO)(L)X (3) in moderate yields with diastereoselectivities of up to 68% de. The configurations of some major diastereomers were determined to be by X-ray crystallography. The diastereoselectivity of 3 was under kinetic control and not affected by the steric effect of the substituents on the Cp′ ring of 1 and the phosphine of 2. Although the double ligand transfer reaction between [Cp′Ru{P(OMe)3}(NCMe)2][PF6] (7) and CpFe(CO)2X (8) produced Cp′Ru{P(OMe)3}(CO)X (9), the selectivity at the ruthenium center was low. 相似文献
109.
Awale S Linn TZ Tezuka Y Kalauni SK Banskota AH Attamimi F Ueda JY Kadota S 《Chemical & pharmaceutical bulletin》2006,54(2):213-218
Ten new furanocassane-type diterpenes named, caesalpinins H-P (1-9) and norcaesalpinin F (10), were isolated from the CH(2)Cl(2) extract of the seed kernels of Caesalpinia crista, together with 13 known diterpenes. Their structures were determined based on the spectroscopic analysis. Among the isolated compounds, caesalpinin N (7) represents the first example of furanocassane-type diterpene possessing an aldehyde group at C-14. 相似文献
110.
Onitsuka K Ohara N Takei F Takahashi S 《Dalton transactions (Cambridge, England : 2003)》2006,(30):3693-3698
Novel trinuclear ruthenium complexes have been prepared by using tri(4-ethynylphenyl)amine as a bridging ligand. Cyclic voltammetry of the trinuclear ruthenium complexes revealed stepwise quasi-reversible redox behavior of three ruthenium-acetylide species and the central triphenylamine unit, whereas the mononuclear analog showed two sequential quasi-reversible redox waves. The spectroelectrochemical UV-VIS spectral studies suggested that the 1e- oxidized triruthenium species was stable and showed a characteristic absorption at lambda(max) = 505 nm. Chemical oxidation of the triruthenium complex with ferrocenium hexafluorophosphate led to the isolation of the 1e- oxidized complex, the near-IR spectrum of which revealed an intervalence charge transfer band due to the electronic coupling among three ruthenium species. The 1e(-) oxidized triruthenium complexes can be classified as class II mixed-valence compounds. 相似文献