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91.
Wang GX Han GF Ye Q Xiong RG Akutagawa T Nakamura T Chan PW Huang SD 《Dalton transactions (Cambridge, England : 2003)》2008,(19):2527-2530
A homochiral rare-earth metal Tb complex that exhibited a very large dielectric anisotropic property with a temperature-independent feature is obtained. Our findings on high-dielectric anisotropy will provide a new impetus in this field of materials science. 相似文献
92.
Abe T Miyakushi S Nagai K Norimatsu T 《Physical chemistry chemical physics : PCCP》2008,10(11):1562-1568
Some types of phthalocyanines (MPc (M = H(2), Cu, or Zn), a p-type semiconductor) were used in combination with 3,4,9,10-perylenetetracarboxyl-bisbenzimidazole (PTCBI, an n-type semiconductor), with which those photoelectrode characteristics in the water phase were investigated in terms of kinetics. Each film of the PTCBI/MPc bilayer functioned as a photoanode, where the photoinduced oxidation of thiol occurs at the MPc/water interface along with the hole conduction through the MPc layer. The holes originate on account of the photophysical events in the p/n interior, involving the charge separation of excitons at the p/n interface. The typical photoelectrochemical characteristic in the PTCBI/MPc photoanodes involved a transient photocurrent occurring in the initial stage under illumination (under potentiostatic conditions): thereafter, it attained a steady state. Moreover, both the initial spiky photocurrents and the steady-state photocurrents exhibited saturation at higher concentrations. An analysis with photoelectrode kinetics was performed by assuming an adsorption step prior to a rate-limiting charge transfer step, where equations were applied to photocurrents based on the Langmuir adsorption equilibrium. The kinetic analyses evidently showed that the photoanodic reactions are kinetically dominated by the charge transfer between MPc and thiol, where the overall kinetics for thiol oxidation decreases in the following order: H(2)Pc > ZnPc > CuPc; that is, it appeared that H(2)Pc acts as the more efficient photofunctional interface capable of oxidation in the water phase when PTCBI was concurrently employed as an electron conductor. Considering that the photocurrent generated is proportional to the surface concentration of thiol (Gamma) at the MPc as well as the intrinsic oxidation rate (cf., ZnPc > H(2)Pc approximately CuPc), the higher efficiency in the output at the H(2)Pc surface was attributed to an exceptionally high Gamma (i.e., from the kinetic analyses, the Gamma value at the H(2)Pc surface was also inferred to be 2-3 times higher than that at the other MPcs). Through the present kinetic analysis, it also revealed that the activity for thiol oxidation taking place at Pc ring is comparable to that at the conventional active catalysts (i.e., polycarboxyphthalocyaninato Co(ii) and Fe(iii)) where a central metal is an active site. 相似文献
93.
Gibbs energies of activation for viscous flow of binary water (1) + dimethyl sulfoxide (2) mixtures, Δμ
12○, and of lysozyme (3) in corresponding ternary mixtures, Δμ
3○, were determined at 298.15 K. The binary mixtures have a maximum in the value of the excess quantity for Δμ
12○ at a dimethyl sulfoxide mole fraction of x
2≈0.31. The values of Δμ
3○ are larger than Δμ
12○ at all values of x
2, even when normalized by their molar volumes, suggesting that the solvents interact more strongly with lysozyme than with
themselves. The values of Δμ
3○ significantly increased in the range of x
2=0.3 to 0.4 because of an increase in solvent-lysozyme interactions, which resulted from an increase in the accessible surface
area of lysozyme that was exposed by its unfolding. The mean value obtained for Δμ
3○ per amino acid of lysozyme at x
2=0.2 is greater than that for hydrophobic amino acids, indicating that the solvent interacts with hydrophilic amino acids
more strongly than with hydrophobic ones. 相似文献
94.
Takahashi T Asami Y Kitamura E Suzuki T Wang X Igarashi J Morohashi A Shinojima Y Kanou H Saito K Takasu T Nagase H Harada Y Kuroda K Watanabe T Kumamoto S Aoyama T Matsumoto Y Bando T Sugiyama H Yoshida-Noro C Fukuda N Hayashi N 《Chemistry & biology》2008,15(8):829-841
Pyrrole-imidazole polyamide (PIP) is a nuclease-resistant novel compound that inhibits gene expression through binding to the minor groove of DNA. Human aurora kinase-A (AURKA) and -B (AURKB) are important regulators in mitosis during the cell cycle. In this study, two specific PIPs (PIP-A and PIP-B) targeting AURKA and AURKB promoter regions were designed and synthesized, and their biological effects were investigated by several in vitro assays. PIP-A and PIP-B significantly inhibited the promoter activities, mRNA expression, and protein levels of AURKA and AURKB, respectively, in a concentration-dependent manner. Moreover, 1:1 combination treatment with both PIPs demonstrated prominent antiproliferative synergy (CI value [ED(50)] = 0.256) to HeLa cells as a result of inducing apoptosis-mediated severe catastrophe of cell-cycle progression. The novel synthesized PIP-A and PIP-B are potent and specific gene-silencing agents for AURKA and AURKB. 相似文献
95.
Nishimura N Tanikawa J Fujii M Kawahara T Ino J Akita T Fujino T Tada H 《Chemical communications (Cambridge, England)》2008,(30):3564-3566
MnO(2) nanoparticle-loaded TiO(2) prepared by a green process capable of removing harmful MnO(4)(-) ions from water exhibits catalytic activity for a test reaction, H(2)O(2) decomposition, in the dark with its activity enhanced by UV light irradiation. 相似文献
96.
Masashi Misawa Takayoshi Ogawa 《Calculus of Variations and Partial Differential Equations》2008,33(4):391-415
We show a regularity criterion to the harmonic heat flow from 2-dimensional Riemannian manifold M into a sphere. It is shown that a weak solution of the harmonic heat flow from 2-dimensional manifold into a sphere is regular
under the criterion
where BMO
r
is the space of bounded mean oscillations on M. A sharp version of the Sobolev inequality of the Brezis–Gallouet type is introduced on M. A monotonicity formula by the mean oscillation is established and applied for proving such a regularity criterion for weak
solutions as above. 相似文献
97.
Mori S Yanase T Aoyagi S Monguchi Y Maegawa T Sajiki H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(23):6994-6999
A variety of aryl iodides were coupled with aromatic and aliphatic terminal alkynes to give the corresponding 1,2-disubstituted aromatic alkynes in good yields by using only 0.4 mol % of the heterogeneous 10 % Pd/C as the catalyst without a ligand, copper salt, or amine in an aqueous medium. 相似文献
98.
Geng F Xin H Matsushita Y Ma R Tanaka M Izumi F Iyi N Sasaki T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(30):9255-9260
We report the synthesis of a new series of layered hydroxides based on rare-earth elements with a composition of RE(OH)2.5Cl(0.5).0.8 H2O (RE: Eu, Tb, etc.) through the homogeneous precipitation of RECl3.x H2O with hexamethylenetetramine (HMT). Rietveld analysis combined with direct methods revealed an orthorhombic layered structure comprising a positively charged layer of [RE(OH)2.5-(H2O)0.8]0.5+ and interlayer Cl- ions. The Cl- ions were readily exchangeable for various anions (NO3-, SO4(2-), dodecylsulfonate, etc.) at ambient temperature. Photoluminescence studies showed that the compounds display typical RE3+ emission. With rare-earth-based host layers and tunable interlayer guests, the new compounds may be of interest for optoelectronic, magnetic, catalytic, and biomedical materials. 相似文献
99.
Takayoshi Ishimoto Masanori Tachikawa Umpei Nagashima 《International journal of quantum chemistry》2008,108(3):472-481
To optimize the exponent values in protonic and deuteronic Gaussian‐type functions (GTF) by the elimination of translational and rotational motions, we have proposed the new scheme of an analytical gradient formula with respect to the exponent values in the multi‐component molecular orbital scheme, which can take into account the quantum effects of protons and deuterons, under the Hartree‐Fock level of theory. Numerical assessment of H2 and D2 molecules confirms that there is a clear difference between distributions of protonic and deuteronic orbitals following the elimination of translational and rotational motions. In particular, the d‐type GTF in the protonic orbital drastically improves the total energy. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
100.
Sonomi Arata Dr. Yuna Kim Prof. Norihisa Hoshino Dr. Keishiro Tahara Dr. Kiyonori Takahashi Dr. Tomofumi Kadoya Tomonori Inoue Prof. Takayoshi Nakamura Prof. Tomoyuki Akutagawa Prof. Jun-ichi Yamada Prof. Kazuya Kubo 《欧洲无机化学杂志》2023,26(12):e202300017
Unsymmetrical gold(III)-dithiolene complexes are potential candidates for molecular materials that exhibit thermal structural phase transitions. In this study, unsymmetrical ppy-gold(III) (ppy−=C-deprotonated-2-phenylpyridine(−)) complexes [AuC5] and [AuC6] coordinated by dithiolene ligands containing tetrathiafulvalene (TTF) skeletons with pentylthio (2-{bis(pentylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) and hexylthio groups (2-{bis(hexylthio)-1,3-dithiol-2-ylidene}-1,3-dithiol-4,5-dithiolate(2−)) were synthesized. Both complexes exhibited a large absorption band at approximately 508 nm, owing to intramolecular ligand-to-ligand charge transfer. One-dimensional columnar structures with head-to-tail molecular arrangements around the metal ions were constructed in the crystals. The flexible alkylthio groups were intercalated into crystalline spaces between dithiolene ligands in the columns. [AuC5] exhibits a simple phase transition at 198 °C between crystalline and isotropic phases irreversibly. The crystalline phase of [AuC6] observed at 25 °C melted at 148 °C. Another crystalline phase grew above 148 °C with a very slow crystallization rate from the liquid phase and was completely transformed into an isotropic phase at 200 °C. 相似文献