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71.
Dr. Keisuke Fujimoto Dr. Seiichiro Izawa Ayumu Takahashi Dr. Toshiyasu Inuzuka Kazutaka Sanada Prof. Dr. Masami Sakamoto Dr. Yasuo Nakayama Prof. Dr. Masahiro Hiramoto Prof. Dr. Masaki Takahashi 《化学:亚洲杂志》2021,16(6):690-695
Curved perylene diimides fused with seven-membered rings have been synthesized using a regioselective bay-functionalization method and Pd-catalyzed intramolecular C−H/C−Br coupling reaction. X-Ray analysis and temperature-dependent NMR spectroscopy revealed the curved molecular structure with a certain degree of conformational flexibility. The curved and expanded π-conjugation altered the electronic properties while retaining the intrinsic properties of the parent perylene diimide. Despite the absence of solubilizing N-substituents, the curved perylene diimides showed sufficient solubility for application in solution-processed organic photovoltaic devices. The devices showed superior performance with a power conversion efficiency of up to 2.76% due to suppressed charge recombination. Our detailed investigations suggest that the introduction of a curved structure enables the removal of the bulky N-substituents, which is an effective way to achieve a thin-film morphology suitable for photoelectric conversion. 相似文献
72.
73.
Toshiyasu Arai 《Archive for Mathematical Logic》2000,39(5):353-391
In this paper we introduce a recursive notation system of ordinals. An element of the notation system is called an ordinal diagram following G. Takeuti [25]. The system is designed for proof theoretic study of theories of recursively Mahlo universes. We
show that for each in
KPM proves that the initial segment of determined by is a well ordering. Proof theoretic study for such theories will be reported in [9].
Received: 13 January, 1998 相似文献
74.
Toshiyasu Arai 《Mathematical Logic Quarterly》2002,48(1):125-130
For α < ε0, Nα denotes the number of occurrences of ω in the Cantor normal form of α with the base ω. For a binary number-theoretic function f let B(K; f) denote the length n of the longest descending chain (α0, …, αn–1) of ordinals <ε0 such that for all i < n, Nαi ≤ f (K, i). Simpson [2] called ε0 as slowly well ordered when B (K; f) is totally defined for f (K; i) = K · (i+ 1). Let |n| denote the binary length of the natural number n, and |n|k the k-times iterate of the logarithmic function |n|. For a unary function h let L(K; h) denote the function B (K; h0(K; i)) with h0(K, i) = K + |i| · |i|h(i). In this note we show, inspired from Weiermann [4], that, under a reasonable condition on h, the functionL (K; h) is primitive recursive in the inverse h–1 and vice versa. 相似文献
75.
Takuya Okada Naizhen Wu Katsuki Takashima Jungoh Ishimura Hiroyuki Morita Takuya Ito Takeshi Kodama Yuhei Yamasaki Shin-ichi Akanuma Yoshiyuki Kubo Ken-ichi Hosoya Hiroshi Tsuneki Tsutomu Wada Toshiyasu Sasaoka Takahiro Shimizu Hideki Sakai Linda P. Dwoskin Syed R. Hussaini Ralph A. Saporito Naoki Toyooka 《Molecules (Basel, Switzerland)》2021,26(24)
The total synthesis of two decahydroquinoline poison frog alkaloids ent-cis-195A and cis-211A were achieved in 16 steps (38% overall yield) and 19 steps (31% overall yield), respectively, starting from known compound 1. Both alkaloids were synthesized from the common key intermediate 11 in a divergent fashion, and the absolute stereochemistry of natural cis-211A was determined to be 2R, 4aR, 5R, 6S, and 8aS. Interestingly, the absolute configuration of the parent decahydroquinoline nuclei of cis-211A was the mirror image of that of cis-195A, although both alkaloids were isolated from the same poison frog species, Oophaga (Dendrobates) pumilio, from Panama. 相似文献
76.
Hinderhofer A Heinemeyer U Gerlach A Kowarik S Jacobs RM Sakamoto Y Suzuki T Schreiber F 《The Journal of chemical physics》2007,127(19):194705
The optical properties of pentacene (PEN) and perfluoropentacene (PFP) thin films on various SiO(2) substrates were studied using variable angle spectroscopic ellipsometry. Structural characterization was performed using x-ray reflectivity and atomic force microscopy. A uniaxial model with the optic axis normal to the sample surface was used to analyze the ellipsometry data. A strong optical anisotropy was observed, and enabled the direction of the transition dipole of the absorption bands to be determined. Furthermore, comparison of the optical constants of PEN and PFP thin films with the absorption spectra of the monomers in solution shows significant changes due to the crystalline environment. Relative to the monomer spectrum, the highest occupied molecular orbital to lowest unoccupied molecular orbital transition observed in PEN (PFP) thin film is reduced by 210 meV (280 meV). A second absorption band in the PFP thin film shows a slight blueshift (40 meV) compared to the spectrum of the monomer with its transition dipole perpendicular to that of the first absorption band. 相似文献
77.
RhCl(PMe3)3 (1) reacts with benzene under irradiation to give the oxidative addition product, Rh(C6H5)(H)Cl(PMe3)3 (2). The reaction is promoted under CO2 atmosphere. The structure of 2 was fully characterized by X-ray crystallography as well as NMR, IR, and elemental analysis. The adduct (2) is unstable in solution even at room temperature to regenerate benzene and 1. The thermolysis of 2 under a CO atmosphere produces benzaldehyde along with the reductive elimination product, benzene. On the other hand, the prolonged photoreaction of 1 with benzene under CO2 resulted in the activation of the C-H bond and CO2 to yield Rh(C6H5)(eta2-CO3)(PMe3)3 (3). 相似文献
78.
The novel polyol compounds, amdigenols E and G, were isolated from the dinoflagellate Amphidinium sp. that was found to adhere to the surface of the marine alga Digenea simplex. The structures of the two amdigenols were elucidated by NMR spectroscopy and ESI–CID-MS/MS analyses. Both amdigenols E and G shared partial structures with amdigenol A. Amdigenols E and G inhibited N-type Ca2+ channel-opening. 相似文献
79.
Ligand‐Controlled Synthesis of [3]‐ and [4]Cyclo‐9,9‐dimethyl‐2,7‐fluorenes through Triangle‐ and Square‐Shaped Platinum Intermediates 下载免费PDF全文
Dr. Eiichi Kayahara Rui Qu Mitsuru Kojima Dr. Takahiro Iwamoto Prof. Dr. Toshiyasu Suzuki Prof. Dr. Shigeru Yamago 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(52):18939-18943
The syntheses of [3]‐ and [4]cyclo‐9,9‐dimethyl‐2,7‐fluorenes ([3] and [4]CFRs), cyclic trimer, and tetramers of 9,9‐dimethyl‐2,7‐fluorene (FR), respectively, were achieved by the platinum‐mediated assembly of FR units and subsequent reductive elimination of platinum. A triangle‐shaped tris‐platinum complex and a square‐shaped tetra‐platinum complex were obtained by changing the platinum ligand. The structure of the triangle complex was unambiguously determined by X‐ray crystallographic analysis. Reductive elimination of each complex gave [3] and [4]CFRs. Two rotamers of [3]CFR were sufficiently stable at room temperature and were separated by chromatography. The physical properties of the CFRs were also investigated theoretically and experimentally. 相似文献
80.
Dr. Seiichiro Izawa Kentaro Uchida Mayuko Nakamura Dr. Keisuke Fujimoto Jérémy Roudin Ji-Hyun Lee Dr. Toshiyasu Inuzuka Takumi Nakamura Prof. Dr. Masami Sakamoto Dr. Yasuo Nakayama Prof. Dr. Masahiro Hiramoto Prof. Dr. Masaki Takahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(56):14081-14091
The influence of N-substituents on the photovoltaic properties of singly bay-linked perylene diimides (diPDIs) was systematically investigated to understand the aromatic-aliphatic balance, which is beneficial for achieving high device performance in organic photovoltaic (OPV) systems. The synthesis of various N-substituted diPDIs was successfully achieved using a newly developed one-step procedure, resulting in sufficiently high yields. Detailed investigations of seven variants of diPDIs demonstrated that the primary alkyl substituents, particularly the 2-ethylhexyl group, induce the self-organized growth of thin films with high crystallinity. This is beneficial for enhancing the device performance of bulk heterojunction (BHJ) systems. The results presented herein reveal the important roles of alkyl side chains as hydrophobic solubilizing auxiliaries or primary determinants in the control of the active layer nanomorphology. This offers a valuable guideline that is essential for developing high-performance organic semiconductor materials for future practical applications. 相似文献