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排序方式: 共有189条查询结果,搜索用时 15 毫秒
1.
Annals of the Institute of Statistical Mathematics - Wasserstein geometry and information geometry are two important structures to be introduced in a manifold of probability distributions.... 相似文献
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Runyan Ni Naoto Mitsuda Takeru Kashiwagi Kazunobu Igawa Katsuhiko Tomooka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(4):1206-1210
A variety of medium‐sized cycloalkynes were efficiently synthesized by the double Nicholas reaction of cobalt complex and bis(hetero)substituted acyclic compound. The alkyne moiety within the ring has a unique bent structure and high reactivity toward cycloaddition reactions. Furthermore, preparation of multifunctionalized alkynes was achieved by embedding the cycloalkyne within a peptide chain. 相似文献
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Fe K‐Edge X‐ray Absorption Fine Structure Determination of γ‐Al2O3‐Supported Iron‐Oxide Species 下载免费PDF全文
Dr. Atsuko Tomita Dr. Takeshi Miki Takeru Tango Tatsuro Murakami Hideyuki Nakagawa Dr. Yutaka Tai 《Chemphyschem》2015,16(9):2015-2020
The structure of FeOx species supported on γ‐Al2O3 was investigated by using Fe K‐edge X‐ray absorption fine structure (XAFS) and X‐ray diffraction (XRD) measurements. The samples were prepared through the impregnation of iron nitrate on Al2O3 and co‐gelation of aluminum and iron sulfates. The dependence of the XRD patterns on Fe loading revealed the formation of α‐Fe2O3 particles at an Fe loading of above 10 wt %, whereas the formation of iron‐oxide crystals was not observed at Fe loadings of less than 9.0 wt %. The Fe K‐edge XAFS was characterized by a clear pre‐edge peak, which indicated that the Fe?O coordination structure deviates from central symmetry and that the degree of Fe?O?Fe bond formation is significantly lower than that in bulk samples at low Fe loading (<9.0 wt %). Fe K‐edge extended XAFS oscillations of the samples with low Fe loadings were explained by assuming an isolated iron‐oxide monomer on the γ‐Al2O3 surface. 相似文献
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Yoshitomo Kashiwagi Yumiko Takamori Kentaro Yoshida Tetsuya Ono 《Electroanalysis》2013,25(12):2575-2577
This paper describes the electrocatalytic oxidation of amines on TEMPO (2,2,6,6‐tetramethylpiperidine‐1‐oxyl)‐modified electrodes prepared by electrochemical copolymerization of TEMPO precursor containing pyrrole side chain and 2,2′‐bithiophene. The modified electrode exhibits electrocatalytic activity for the oxidation of primary and secondary amines. Cyclic voltammetric studies showed that the peak current of the cyclic voltammogram increased linearly with increasing concentration of amine in the sample solution. 相似文献
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This paper is concerned with the construction of basis matrices of visual secret sharing schemes for color images under the
(t, n)-threshold access structure, where n ≥ t ≥ 2 are arbitrary integers. We treat colors as elements of a bounded semilattice and regard stacking two colors as the join
of the two corresponding elements. We generate n shares from a secret image with K colors by using K matrices called basis matrices. The basis matrices considered in this paper belong to a class of matrices each element of
which is represented by a homogeneous polynomial of degree n. We first clarify a condition such that the K matrices corresponding to K homogeneous polynomials become basis matrices. Next, we give an algebraic scheme for the construction of basis matrices.
It is shown that under the (t, n)-threshold access structure we can obtain K basis matrices from appropriately chosen K − 1 homogeneous polynomials of degree n by using simple algebraic operations. In particular, we give basis matrices that are unknown so far for the cases of t = 2, 3 and n − 1. 相似文献
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Meifang Liu Xin ZhangMauro Zammarano Jeffrey W. GilmanTakashi Kashiwagi 《Polymer Degradation and Stability》2011,96(5):1000-1008
A combination of montmorillonite (MT) clay and catalysts was used to explore possible synergistic effects in reducing the flammability of poly(styrene-co-acrylonitrile) (SAN). Several catalysts, including ammonium phosphomolybdate hydrate (NHPMo), melamine phosphomolybdate hydrate (MEPMo), zinc phosphomolybdate hydrate (ZnPMo) and sodium phosphomolybdate hydrate (NaPMo), were used. The combination of MT (Cloisite 20A) with NHPMo showed synergistic enhancement in improving the char formation and reducing the peak mass loss rate of SAN40 as compared with SAN40 composites containing MT or NHPMo alone, while similar synergistic performance was not obtained between MT and NaPMo or ZnPMo or MEPMo. The better flame retardancy with this combination is probably due to the two primary aspects. One is the increased catalytic activity of the combination of Cloisite 20A and NHPMo probably due to the overlapping degradation temperature range of the combination of 20A/NHPMo and SAN40, which probably results in more char formation; the other is more NHPMo being around or on the clay stacks while less is in the galleries of the clay; this probably bridges the clay stacks and strengthens the clay network with char formed during the degradation process. High temperature rheological data confirmed the formation of a stronger network structure in SAN40/20/NHPMo; this benefits flame retardancy by allowing fewer cracks to form in the outer char layer on the polymer mass. The more continuous char layer suppresses bubbles transport of fuel vapors and heat transfer through the char layer, thereby reducing the mass loss rate. 相似文献
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Tomohiro Ohta Takeru Ito Masahiro Shimizu Lisa Tauchi Huy‐Danh Nguyen‐Tran Jong‐Chul Park Byoung‐Suhk Kim Ick‐Soo Kim Kazuchika Ohta 《先进技术聚合物》2011,22(12):2653-2658
We have developed a novel synthetic method that enables us to easily synthesize metal‐capsulated carbon nanotubes (CNTs) in a laboratory by using a combined technology of electrospinning‐metallization and microwave heating. These techniques greatly shorten the time for the synthesis of the CNTs in comparison with the conventional methods. TEM analysis confirmed a successful formation of the CNTs, and the resulting CNTs were multi‐walled and found to be about 25–100 nm in diameters. The products prepared by heating at 600 and 900°C exhibited less‐developed and strongly curved CNTs, whereas the products prepared by heating at 700 and 800°C relatively well‐developed long CNTs. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
10.
C-F Bond Formation for the Synthesis of Aryl Fluorides 总被引:2,自引:0,他引:2
A selection of carbon-fluorine bond-forming reactions is presented with particular focus on transition metal-mediated fluorination. A brief summary of conventional fluorination reactions is followed by a discussion of fluorination reactions mediated by palladium and silver. Investigations into the mechanism as well as the conceptual difficulty associated with transition metal-mediated carbon-fluorine bond formation are presented. 相似文献