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91.
Regiospecific Coordination of Re3 Clusters with the Sumanene‐Type Hexagons on Endohedral Metallofullerenes and Higher Fullerenes That Provides an Efficient Separation Method 下载免费PDF全文
Dr. Chia‐Hsiang Chen Dong‐Yui Lin Dr. Wen‐Yann Yeh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5768-5775
The reactions of [(μ‐H)3Re3(CO)11(NCMe)] with Sc2@C82‐C3v(8), Sc2C2@C80‐C2v(5), Sc2O@C82‐Cs(6), C86‐C2(17), and C86‐Cs(16) have been carried out to produce face‐capping cluster complexes. The Re3 triangles are found to bind to the sumanene‐type hexagons on the fullerene surface regiospecifically. In contrast, Sc3N@C78‐D3h(5) and Sc3N@C80‐Ih show no reactivity toward [(μ‐H)3Re3(CO)11(NCMe)], probably due to electronic and steric factors. These complexes can be easily purified by using HPLC. Carbonylation of each complex releases the corresponding higher fullerene or endohedral metallofullerene in pure form. Remarkably, the C86‐C2(17) and C86‐Cs(16) isomers were successively separated through Re3 cluster complexation/decomplexation. This unique bonding feature may provide an attractive general strategy to purify as yet unresolved fullerene mixtures. 相似文献
92.
So‐Hsiang Chou Songnian He Wen‐Wei Lin 《Numerical Methods for Partial Differential Equations》2004,20(1):104-127
Compared with standard Galerkin finite element methods, mixed methods for second‐order elliptic problems give readily available flux approximation, but in general at the expense of having to deal with a more complicated discrete system. This is especially true when conforming elements are involved. Hence it is advantageous to consider a direct method when finding fluxes is just a small part of the overall modeling processes. The purpose of this article is to introduce a direct method combining the standard Galerkin Q1 conforming method with a cheap local flux recovery formula. The approximate flux resides in the lowest order Raviart‐Thomas space and retains local conservation property at the cluster level. A cluster is made up of at most four quadrilaterals. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 104–127, 2004 相似文献
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Wu-Yi Hsiang 《Milan Journal of Mathematics》2005,73(1):177-186
No Abstract. .
Lecture held in the Seminario Matematico e Fisico on May 26, 2004 Received: August 2004 相似文献
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Guey‐Sheng Liou Sheng‐Huei Hsiao Tzy‐Hsiang Su 《Journal of polymer science. Part A, Polymer chemistry》2005,43(15):3245-3256
We describe the preparation, characterization, and luminescence of four novel electrochromic aromatic poly(amine hydrazide)s containing main‐chain triphenylamine units with or without a para‐substituted N,N‐diphenylamino group on the pendent phenyl ring. These polymers were prepared from either 4,4′‐dicarboxy‐4″‐N,N‐diphenylaminotriphenylamine or 4,4′‐dicarboxytriphenylamine and the respective aromatic dihydrazide monomers via a direct phosphorylation polycondensation reaction. All the poly(amine hydrazide)s were amorphous and readily soluble in many common organic solvents and could be solution‐cast into transparent and flexible films with good mechanical properties. These poly(amine hydrazide)s exhibited strong ultraviolet–visible absorption bands at 346–348 nm in N‐methyl‐2‐pyrrolidone (NMP) solutions. Their photoluminescence spectra in NMP solutions or as cast films showed maximum bands around 508–544 and 448–487 nm in the green and blue region for the two series of polymers. The hole‐transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. All obtained poly(amine hydrazide)s and poly(amine‐1,3,4‐oxadiazole)s exhibited two reversible oxidation redox couples at 0.8 and 1.24 V vs. Ag/AgCl in acetonitrile solution and revealed excellent stability of electrochromic characteristics, changing color from original pale yellow to green and then to blue at electrode potentials of 0.87 and 1.24 V, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3245–3256, 2005 相似文献
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I‐Ling Lin I‐Hsiang Chen Chi‐Fong Lin Yu‐Hsiang Lo Sheng‐Huei Yang Shinne‐Ren Lin Ming‐Jung Wu 《中国化学会会志》2008,55(3):668-674
A series of 1‐(6‐(2‐(2‐arylethynyl)phenyl)hexyn‐5‐yl)piperidin‐2‐ones 2a‐j were synthesized and their antitumor activities were evaluated. Of these compounds, 1‐(6‐(2‐(2‐(4‐nitrophenyl)ethynyl)phenyl)hexyn‐5‐yl)piperidin‐2‐one ( 2j ) showed the highest potency of growth inhibition activity, especially against the RPMI‐8226 (0.4 μM) and SR (0.02 μM) cell lines of human leukemia. Compound 2j also induced significant apoptotic progress in the cell cycle assay with the K‐562 cell line. 相似文献
100.
Wu MY Chen BG Chang CD Huang MH Wu TG Chang DM Lee YJ Wang HC Lee CI Chern CL Liu RH 《Journal of chromatography. A》2008,1204(1):81-86
A two-step derivatization approach has been developed to enable the simultaneous analysis of glyoxal, methylglyoxal, and 3-deoxyglucosone by the most efficient and widely applied GC-MS methodology. These three analytes are reactive carbonyl compounds associated with the formation of advanced glycation and lipoxidation end products, a process thought to contribute to uremic toxicity and referred to as "carbonyl stress". Effective analysis of these compounds would facilitate understanding these compounds' role in diabetes-related complications. Plasma samples were deproteinized by acetonitrile, followed by a two-step derivatization approach. Pooled plasma samples from healthy individuals were used as the "blank" for preparing calibration standards. The concentrations of the analytes in the "blank" were first determined by standard addition method. Calibration parameters were accordingly established and used to analyze these compounds in plasma samples collected from healthy individuals and diabetic patients. Analytical findings are comparable with those reported in the literature. Quantitation data can be further improved by making available and using isotopically labeled analogs of these analytes as the internal standards. 相似文献