Browsing by Author "Li, H"

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Interleaver technology: Comparisons and applications requirements
(2004-01-01)
Cao, S
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Chen, J
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Damask, JN
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Doerr, CR
;
Guiziou, L
An overview of interleaver technologies is presented, based on the workshop held at the Optical Fiber Communications Conference, March 23, 2003. The requirements for and several realizations of interleaver filters are detailed.
Kinetics of decomposition of polyethylene glycol in electroplating solution by ozonation with UV radiation
(2001-10-01)
Chang, CY
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Chen, YH
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Li, H
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Chiu, CY
;
Yu, YH
The kinetics of the ozonation of polyethylene glycol (PEG) with ultraviolet (UV) radiation in the acid-based electroplating solution of the printed wiring board industry is studied. The substrate prescription of a typical electroplating solution is with pH of 0. 18-0.42, [CuSO4 . 5H(2)O] of 200 g/L, [H2SO4] of 60 g/L, and [Cl-] of 0.03 g/L. Certainly, the discarded electroplating solution is hard to treat with the common chemical and biological processes because of its acidic and metallic compositions. In addition, it contains valuable substances suitable for recovery and reutilization. One of the most important processes for reviving it is to remove the aged organic additives such as PEG. A two-step reaction mechanism in terms of ozone A and total organic carbon is proposed to express the reaction kinetics of PEG ozonation with UV radiation with intensity [I-uv]. The initial concentration of PEG is 30 mg/L, according to the recipe of a typical electroplating solution, which is equivalent to total organic carbon of 16.3 mg/L. The reaction rate r expressions of the concentrations of the liquid phase ozone C-ALb, PEG C-BLb, and intermediates C-ILb are r(A) (=dC(ALb)/dt) = -(k(Am) + k(t)[I-uv)C-ALb (k(R1) + k(RI1)[I-uv])CALbCBLb - (k(R2) + k(RI2)[I-uv])CALbCILb, r(B) (=dC(BLb)/dt) = -(k(R1) + k(RI1)[I-uv])CALbCBLb, r(int) (=dC(ILb)/dt) (k(R1) + k(RI1)[I-uv])CALbCBLb - (k(R2) + k(RI2)[I-uv])CALbCILb, with k(Am) = 0.0036 s(-1), k(1) = 4.654 X 10(-5)s(-1)/(Wm(-2)), k(R1) = 13.525 M(-1)s(-1), k(R2) = 0.751 M(-1)s(-1), k(RI1) = 0.683 M(-1)s(-1)/(Wm(-2)), and k(RI2) = 0.042 M(-1)s(-1)/(Wm(-2)). These reaction kinetic expressions are useful and referable for the proper design of an ozonation system with UV radiation for the treatment of PEG in the printed wiring board electroplating solution.
Syntheses and characterizations of soft-segment ionic polyurethanes
(1999-04-15)
Wang, XL
;
Li, H
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Tang, XZ
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Chang, FC
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應用化學系
Novel soft-segment ionic polyurethane (linear and crosslinking) have been prepared based up on sodium sulfonate-side chains poly(ethylene oxide) (SPEO). SPEO was synthesized by grafting the sodium sulfonate onto the chain of poly(ethylene oxide) with molecular weights of 400, 600, 800, and 1000. The SPEO and the ionic polyurethane were characterized by elemental analysis, IH;NMR, C-13-NMR, gel permeation chromatography, and impedance analysis. The effect of plasticizer on the ionic conductivity of the polyurethane was also investigated. These solid polymer electrolytes possess a higher ionic conductivity (about 10(-6) S/cm at room temperature) than the corresponding sulfonated hard-segment polyurethane electrolytes. The presence of the hydroxyl group in the electrolyte tends to lower the ionic conductivity. Crosslinking of polyurethane results in the enhancement of the dimensional stability, while maintaining the same level of the ionic conductivity. (C) 1999 John Wiley & Sons, Inc.
Syntheses of poly(ethylene oxide) polyurethane ionomers
(2000-07-05)
Wang, XL
;
Wang, L
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Li, H
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Tang, XZ
;
Chang, FC
Sulfonated dimethyl fumarate (SDMF) was prepared with dimethyl fumarate (DNF) and sodium hydrogensulfite (NaHSO3). Sodium sulfonate side-chain poly(ethylene oxide) (SPEO) was synthesized by grafting sodium sulfonate onto the chain of PEO with molecular weights of 400, 600, 800, and 1000. SPEO was used subsequently in step-growth polymerization to give a polyurethane ionomer (SPU). Samples were characterized by element analysis, FTIR, H-1-NMR, EDX mapping, X-ray, gel permeation chromatography, and impedance analysis. The SPUs exhibited an amorphous structure. The maximum conductivity of the SPU was 1.02 x 10(-6) S cm(-1) at the room temperature. (C) 2000 John Wiley & Sons, Inc.