• Title/Summary/Keyword: J.S.P.

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A Study on the Hydrolysis of Sarin and Soman by Merrifield-Type Diaminatedpolystyrene-Cu (II) Heterogeneous Polymers (Merrifield-Type Diaminatedpolystyrene-Cu (II) 불균일 촉매에 의한 Sarin과 Soman 분해반응 연구)

  • 정우영;계영식
    • Journal of the Korea Institute of Military Science and Technology
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    • v.3 no.1
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    • pp.164-175
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    • 2000

  • Three compounds of Cu(II)-loaded N,N,N'-trimethylethylenediaminated Merrifield-type polymers were synthesized with yields higher than 80%, and the hydrolysis reaction rates of O-isopropylmethyl-phosphonofluoridate(GB) and O-pinacolylmethylphosphonofluoridate (GD) catalyzed by them have been surveyed. GB and GD hydrolysis by Cu(II)-loaded polymers occurs via intermediate complex mechanism where rapid equilibrium to form intermediate complex between substrate and Cu(II)-loaded polymers($K_f$) is followed by rate determining hydrolysis step($k_1$). The measured activation parameters for $k_1$ are ${\Delta}H^{\ddag}$ : $17.75{\pm}0.98kJ/mol$ ${\Delta}S^{\ddag}$ / : $-218.42{\pm}3.35J/mol$ K, $E^{\circ}_a$ : $20.22{\pm}0.98kJ/mo1$ for GB and ${\Delta}H^{\ddag}$ / : $11.16{\pm}1.15kJ/mol,$${\Delta}S^{\ddag}$ /: $-258.57{\pm}3.93J/mol$ K, $E^{\circ}_a$ : $13.64{\pm}1.15 kJ/mol$ for GD. Standard enthalpy/entropy changes corresponding to the intermediate complex formation constant $K_f$ are ${\Delta}H^{\circ}$ : $37.05{\pm}2.19 kJ/mo1,$$ {\Delta}S^{\circ}$ : $163.12{\pm}7.49 J/mol$ K and ${\Delta}H^{\circ}$ : 418.59{\pm}2.04 kJ/mol,$ ${\Delta}S^{\circ}$ : 4111.92{\pm}6.98 J/mol$ K for GB and GD, respectively, The electron push-pull mechanism by Cu(II)-loaded polymers lowers the P-F bond breaking energy(~400 kJ/mol) to less than 1/20 compared to the case in which no Cu(II)-loaded resin presents. Analysis of $K_f$ and 4k_1$ over pH=6.5~8.0 range suggest that the GB and GD hydrolysis occurs intramolecularily with $pK_a$ =7.29 for ligated $H_2O$ and $t_{1/2}$=36.9 sec, $pK_a$ = 7.06 and $t_{1/2}$=177.7 sec for GB and GD, respectively.

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A New MPPT Algorithm based on P&O Algorithm (P&O 알고리즘을 개선한 새로운 MPPT 알고리즘)

  • Jung Y.S.;Yu G.J.;So J.H.;Choi J.Y.;Choi J.H.
    • Proceedings of the KIPE Conference
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    • 2003.07b
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    • pp.925-928
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    • 2003

  • As the maximum power operating point(MPOP) of photovoltaic(PV) power generation systems changes with changing atmospheric conditions such as solar radiation and temperature, an important consideration in the design of efficient PV system is to track the MPOP correctly. Many maximum power point tracking(MPPT) techniques have been considered in the past, however, techniques using microprocessors with appropriate MPPT algorithms are favored because of their flexibility and compatibility with different PV arrays. Although the efficiency of these MPPT algorithms is usually high, it drops noticeably in case of rapidly changing atmospheric conditions. This paper proposed a new MPPT algorithm based on perturb & observe(P&O) algorithm with experiment. The results shows that the new P&O algorithm has successfully tracked the MPOP, even in case of rapidly changing atmospheric conditions, and has higher efficiency than ordinary algorithms.

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