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41.
The design of hermetically double-coated optical fibers to minimize hydrostatic pressure–induced stresses is investigated. Several stresses are important in the hermetically double-coated optical fibers, and they would produce the excess bending losses or the failure of hermetic coatings. These stresses can be minimized by appropriately selecting material's properties of hermetic coatings and their thicknesses. The hydrostatic pressure–induced stresses in optical fibers with some selected metallic coatings are also considered. The results show that chromium has the best performance in the minimization of hydrostatic pressure–induced stresses. However, lead and indium are poor materials. 相似文献
42.
HeTianxiao LeetsehC.Hsu PeterJ.S.Shiue 《分析论及其应用》2003,19(2):166-184
In this paper a connective study of Gould‘s annihilation coefficients and Abel-Gontscharoff polynomials is presented. It is shown that Gould‘s annihilation coefficients and Abel-Gontscharoff polynomials are actually equivalent to each other under certain linear substitutions for the variables. Moreover, a pair of related expansion formulas involving Gontscharoff‘s remainder and a new form of it are demonstrated, and also illustrated with several examples. 相似文献
43.
Hung‐Ju Yen Shiue‐Ming Guo Guey‐Sheng Liou 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5271-5281
Two series of new organosoluble polyamides with methyl‐substituted triphenylamine (MeTPA) units showing anodically electrochromic characteristic were prepared from the phosphorylation polyamidation reaction of two diamine monomers, 4,4′‐diamino‐2″,4″,6″‐trimethyltriphenylamine (Me3TPA‐diamine; 2 ) and 4,4′‐diamino‐4″‐methyltriphenylamine (MeTPA‐diamine; 2 ′), with various dicarboxylic acids, respectively. These polymers were readily soluble in many polar solvents and showed useful levels of thermal stability associated with relatively high glass‐transition temperatures (Tg) (314–329 °C) and high char yields (higher than 62% at 800 °C in nitrogen). In addition, the polymer films showed reversible electrochemical oxidation, high coloration efficiency (CE), low switching time, and anodic green electrochromic behavior. The unexpected electrochemical behavior of higher oxidation potential and lower electrochemical stability of Me3TPA‐polyamides I than MeTPA corresponding polymers could be attributed to the higher steric hindrance of ortho‐substituents in Me3TPA moieties, thus made the resonance stabilization of cation radical much more difficult for the Me3‐substituted phenyl ring. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
44.
Hung‐Ju Yen Shiue‐Ming Guo Guey‐Sheng Liou Jen‐Chieh Chung Yu‐Chang Liu Yung‐Fang Lu Yu‐Zhen Zeng 《Journal of polymer science. Part A, Polymer chemistry》2011,49(17):3805-3816
A series of solution‐processable electrochromic (EC) aromatic polyamides with bis(triphenylamine)ether (TPAO) units in the backbone were prepared by the phosphorylation polyamidation from a newly synthesized diamine monomer, bis(N‐4‐aminophenyl‐N‐4‐methoxyphenyl‐4‐aminophenyl)ether, and various dicarboxylic acids. These polymers were highly soluble in many organic solvents and showed useful levels of thermal stability associated with high glass‐transition temperatures and high char yields (higher than 50 at 800 °C in nitrogen). The polymer films showed reversible electrochemical oxidation and electrochromism with high contrast ratio in the visible range, which also exhibited moderate coloration efficiency (CE), low switching time, and good stability. Especially, the polyamides with two electroactive nitrogen centers only showed one‐stage oxidative coloring (no intervalence charge‐transfer [IV‐CT] band was detected), implying the two electrons are simultaneously removed from the TPAO units on account of the ether‐linkage definitely isolated the two redox centers. The mixed‐valence (MV) Class I/II/III transition and electrochemistry of the synthesized model compounds were investigated for the bridged triarylamine system with various N? N distances and intramolecular electron transfer (ET) capability. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
45.
Hung‐ju Yen Shiue‐ming Guo Jui‐ming Yeh Guey‐Sheng Liou 《Journal of polymer science. Part A, Polymer chemistry》2011,49(16):3637-3646
Two series of polyimides I – II with methyl‐substituted triphenylamine units were prepared from the diamines, 4,4′‐diamino‐2″,4″,6″‐trimethyltriphenylamine (Me3TPA‐diamine; 1 ) and 4,4′‐diamino‐4″‐methyltriphenylamine (MeTPA‐diamine; 2 ), and two commercially available tetracarboxylic dianhydrides via a conventional two‐step chemical imidization. All the polymers were readily soluble in many polar solvents and showed useful levels of thermal stability associated with high glass transition temperatures (266–340 °C) and high char yields (higher than 49% at 800 °C in nitrogen). The polymer films showed reversible electrochemistry/electrochromism accompanied by a color change from neutral pale yellow to green oxidized form with good coloration efficiency, switching time, and stability. The CO2 permeability coefficients (PCO2) and permeability selectivity (PCO2/PCH4) for these polyimide membranes were in the range of 34.1–229.2 barrer and 21.3–28.9, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
46.
M. Speranza C.-Y. Shiue A.P. Wolf D.S. Wilbur G. Angelini 《Journal of fluorine chemistry》1985,30(1):97-107
The reactions of a variety of aryltrimethylsilanes with elemental fluorine and acetyl hypofluorite have been studied with the aim of developing a general method for labeling aromatic compounds with fluorine-18. Extensive 18F incorporation into the aromatic ring of the selected aryltrimethylsilanes was invariably observed, leading to the ipso (18F-for-Si) electrophilic substitution products together with variable yields of other (18F-for-H) electrophilic substitution products. The relative extent of the 18F substitution processes [(C-Si/C-H)subst.] is found to depend largely upon the substituent group on the aromatic ring of the substrate, the leaving moiety, and the radiofluorination procedure used. The utility of aryltrimethylsilyl derivatives as precursors for the rapid synthesis of high specific activity of 18F-labeled radiopharmaceuticals is discussed. 相似文献
47.
W.-S. Chou Leetsch C. Hsu Peter J.-S. Shiue 《Journal of Computational and Applied Mathematics》2006,190(1-2):151-169
It is shown that a pair of inverse relations can be constructed by the suitable application of Faà di Bruno's formula for finding higher order derivatives of composite functions. Various examples illustrating the applications of inverse relations are presented. 相似文献
48.
Wen-Kwei Shiue 《Rendiconti del Circolo Matematico di Palermo》2003,52(3):505-509
LetR a prime ring,L a noncentral Lie ideal ofR anda ∈R. Suppose thatd is a nonzero derivation ofR such thata[d(u),u]
k
=0 for allu ∈L, wherek is a fixed positive integer. Thena=0 except when charR=2 and dim
C
RC=4. 相似文献
49.
The design of double-coated optical fibers to minimize long-term axial-strain-induced microbending losses is investigated. The microbending loss is dominated by the compressive radial stress at the interface between the glass fiber and primary coating. To know the long-term axial-strain-induced microbending losses in double-coated optical fibers, the stresses in fibers are analyzed by the viscoelastic theory. To minimize these long-term microbending losses, the thickness and Young's modulus of the secondary coating should be decreased if the strength of coating is satisfied. Meanwhile, the Poisson's ratio of the primary coating should be increased, but the Young's modulus of the primary coating and relaxation time of the secondary coating should be decreased. Alternatively, the radius and relaxation time of the primary coating exist their optimum values. The long-term axial-strain-induced microbending losses in single-coated optical fibers are also discussed. 相似文献
50.
Fu H. L. Shiue C. L. Cheng X. Du D. Z. Kim J. M. 《Journal of Optimization Theory and Applications》2001,110(3):545-556
Let be a permutation of the vertex set V(G) of a connected graph G. Define the total relative displacement of in G by be
where
dG(x, y)
is the length of the shortest path between x and y in G. Let *
(G) be the maximum value of
(G) among all permutations of V(G). The permutation which realizes *
(G) is called a chaotic mapping of G. In this paper, we study the chaotic mappings of complete multipartite graphs. The problem is reduced to a quadratic integer programming problem. We characterize its optimal solution and present an algorithm running in
time, where n is the total number of vertices in a complete multipartite graph. 相似文献