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61.
62.
Nozomu Tsuboi Takanobu Hoshino Tomonori Suzuki Keizo Kato Futao Kaneko 《Journal of Physics and Chemistry of Solids》2005,66(11):2134-2138
Delafossite-type oxides of CuTbyY1−yO2, CuEuyY1−yO2, CuCaxTbyY1−x−yO2 and CuCaxEuyY1−x−yO2 have been prepared by solid state reactions. The lattice-parameter dependence on the composition implies substitution of the Tb3+, Eu3+ and Ca2+ cations for the Y3+ site. Noticeable sharp emission lines due to the f-f transitions (5D4→7FJ, J=3-6) of Tb3+ or due to the f-f transitions (5D0→7FJ, J=0-4) of Eu3+ are observed at room temperature. Electrical conductivities of CuCaxTbyY1−x−yO2 and CuCaxEuyY1−x−yO2 are larger than those of CuTbyY1−yO2 and CuEuyY1−yO2, indicating the increase of the hole concentration caused by the substitution of Ca2+ for the Y3+ site. These results indicate the controllability of the luminescence and conductivity in CuCaxTbyY1−x−yO2 and CuCaxEuyY1−x−yO2 delafossite-type oxides by simultaneous substitution of the rare earth Tb3+ or Eu3+ cation and the Ca2+ cation for the Y3+ site. 相似文献
63.
Takashi Yasui Nozomu Komatsu Kazuki Egami Hiromichi Yamada Akio Yuchi 《Analytical sciences》2007,23(8):1011-1014
Bidentate and tridentate heterocyclic azo compounds with and without a long alkyl chain were prepared and examined for cation exchange chromatography of manganese, zinc, and cadmium; these ions could not be separated by reversed phase HPLC following precolumn derivatization with heterocyclic azo compounds owing to the dissociation of the complexes. The newly prepared azo compounds having a long alkyl chain favorably orientate in the reversed-phase stationary phase such that the coordinating parts of the ligand may make contact with metal ions in the mobile phase. Bidentate ligands showed sharp peaks but almost no resolution of manganese and cadmium. A tridentate ligand strongly retained all the three metal ions, which could be separated within 10 min by a competing ligand and by optimizing the pH. 相似文献
64.
K. Tanihara 《Journal of Radioanalytical and Nuclear Chemistry》1991,153(6):399-408
In the presence of trace amounts of hydrazinium or amidosulfate ion, sufficiently high values were observed for the distribution coefficients of cesium on several insoluble ferrocyanide sorbents in a concentrated solution of nitric acid, in contrast to considerably lower values in their absence. The results indicate an inhibitory action of the above agents on the oxidation of ferrocyanide to ferricyanide with nitric acid. 相似文献
65.
Yamaoka H Jarrige I Tsujii N Lin JF Ikeno T Isikawa Y Nishimura K Higashinaka R Sato H Hiraoka N Ishii H Tsuei KD 《Physical review letters》2011,107(17):177203
We have investigated the temperature and pressure dependency of the electronic structure of Yb-filled skutterudites, YbFe(4)Sb(12) and Yb(0.88)Fe(4)Sb(12), using x-ray absorption and emission spectroscopies. An anomalous increase of the Yb valence, which is beyond the conventional Anderson model picture, is found to coincide with the onset of the ferromagnetic order in the x=0.88 sample below 20 K. In contrast, the nearly stoichiometric YbFe(4)Sb(12) is paramagnetic down to 2 K and the Yb valence is independent of temperature. This evidences a close interplay between the magnetic instability of the Fe 3d electrons and valence instability of the Yb 4f electrons. Under pressure, a sudden increase in the valence is found to occur around 13 GPa for YbFe(4)Sb(12) and 17 GPa for Yb(0.88)YbFe(4)Sb(12). 相似文献
66.
Makoto Obata Eiko Ohtake Shiho Hirohara Masao Tanihara Shigenobu Yano 《Journal of polymer science. Part A, Polymer chemistry》2012,50(17):3592-3597
In this article, we offer clear evidence for the radical copolymerizability of porphyrin rings in 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO)‐mediated radical copolymerizations with styrene. The radical copolymerizations of styrene with 5,10,15,20‐tetrakis(pentafluorophenyl)porphyrin (H2TFPP) was conducted using 1‐phenyl‐1‐(2,2,6,6‐tetramethyl‐1‐piperidinyloxy)ethane as an initiator. The refractive index (RI) traces for the size‐exclusion chromatography of the resulting copolymers were unimodal with narrow molecular weight distributions. The RI traces shifted toward higher molecular weight regions as the polymerization progressed, and the number‐average molecular weights were close to those calculated on the basis of the feed compositions and monomer conversions. These features were in good agreement with a TEMPO‐mediated mechanism. The traces recorded by the ultraviolet‐visible (UV‐vis) detector (430 nm) were identical to those obtained by the RI detector, indicating a statistical copolymerization of styrene with H2TFPP. This also indicated that H2TFPP acted as a monomer and not as a terminator or a chain‐transfer agent under the conditions used. A benzyl radical addition to H2TFPP was conducted as a model reaction for the copolymerization using tributyltin hydride as a chain‐transfer agent, affording a reduced porphyrin, 2‐benzyl‐5,10,15,20‐tetrakis(pentafluorophenyl)chlorin 1 , via radical addition to the β‐pyrrole position. The UV‐vis spectrum of 1 was fairly similar to that of poly(styrene‐co‐H2TFPP), indicating that H2TFPP polymerized at its β‐pyrrole position in the TEMPO‐mediated radical polymerization. TEMPO‐mediated radical copolymerizations of styrene with several porphyrin derivatives were also demonstrated. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
67.
The hydrogen abstraction reactions from hydrazine and its methyl derivatives by the H atom have been investigated theoretically by using CBS-QB3//DSD-BLYP-D3(BJ)/Def2-TZVP quantum chemical calculations and transition state theory calculations coupled with various tunneling correction methods. Both the products and transition state energies of the hydrogen abstraction from the amino group were stabilized by the methyl group substitution. The substitution effect on the αN site was two times larger than that on the βN site. On the other hand, the substitution effect was negligible on the hydrogen abstraction from the methyl group. The overall rate coefficients of N2H4 + H reaction calculated by canonical variational transition state theory with the small-curvature tunneling correction agreed well with previously reported values, but those of CH3NHNH2/(CH3)2NNH2 + H were slightly lower than a previous experimental value. The product-specific rate coefficients have been proposed for the kinetics modeling of these fuels’ combustion. 相似文献
68.
Dominik Karos Nozomu Muto Shiran Rachmilevitch 《International Journal of Game Theory》2018,47(4):1169-1182
We characterize the class of weakly efficient n-person bargaining solutions that solely depend on the ratios of the players’ ideal payoffs. In the case of at least three players the ratio between the solution payoffs of any two players is a power of the ratio between their ideal payoffs. As special cases this class contains the Egalitarian and the Kalai–Smorodinsky bargaining solutions, which can be pinned down by imposing additional axioms. 相似文献
69.
Hirosuke Matsui Naoyuki Maejima Nozomu Ishiguro Yuanyuan Tan Tomoya Uruga Oki Sekizawa Tomohiro Sakata Mizuki Tada 《Chemical record (New York, N.Y.)》2019,19(7):1380-1392
Three‐dimensional imaging using X‐ray as a probe is state‐of‐the‐art for the characterization of heterogeneous materials. In addition to simple imaging of sample morphology, imaging of elemental distribution and chemical states provides advanced maps of key structural parameters of functional materials. The combination of X‐ray absorption fine structure (XAFS) spectroscopy and three‐dimensional imaging such as computed tomography (CT) can visualize the three‐dimensional distribution of target elements, their valence states, and local structures in a non‐destructive manner. In this personal account, our recent results on the three‐dimensional XAFS imaging for Pt cathode catalysts in the membrane electrode assembly (MEA) of polymer electrolyte fuel cell (PEFC) are introduced. The distribution and chemical states of Pt cathode catalysts in MEAs remarkably change under PEFC operating conditions, and the 3D XAFS imaging revealed essential events in PEFC MEAs. 相似文献
70.
We established a simple cryopreservation protocol for Arabidopsis T87 cells using an encapsulation-dehydration method. T87 cells were encapsulated into alginate beads containing 2 M glycerol and 0.4 M sucrose. Alginate beads containing T87 cells were dehydrated with silica gel for 2 h (to c. 0.7 g water per g dry weight followed by immersed in LN. After rewarming at 35 degree C for 3 min and 1-d incubation under continuous illumination at 22 degree C, cryopreserved T87 cells exhibited considerable regrowth. Exponentially-grown 7-d-old T87 cells regrew more vigorously (86% of control) than 14-d-old cells after cryopreservation without preculture in medium containing 0.3 M sucrose. Genetic stability of cryopreserved T87 cells was demonstrated by gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) and principal component analysis (PCA). Transformed T87 cells were cryopreserved using established protocols, and GUS expression was maintained within a 2-fold variance. These results indicate that cryopreservation of T87 cells is useful for comprehensive metabolomics research and for the large scale collection of transformed cultured cell lines for functional genomics research. 相似文献