• 대한화학회지
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• 제45권1호
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• pp.7-13
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• 2001

양이온 계면활성제인 TTAB(tetradecyltrimethylammonium bromide)의 수용액에서 benzenesulfonate 음이온과 유도체($C_6H_5SO_3^-, p-$CH_3C_6H_4SO_3^- 및 $p-C_2H_5C_6H_4SO_3^-$)들의 가용화 현상을 UV/Vis 분광광도법을 이용하여 연구하였다. 온도의 변화에 따른 가용화상수($K_s$)의 변화를 측정하고 분석하였으며, 또한 가용화에 영향을 미치는 n-펜탄올과 NaBr의 효과에 대하여 조사하였다. 이러한 첨가제는 $K_s$와 CMC 값을 동시에 큰 폭으로 감소시키는 경향을 나타내었으며, 측정한 In$K_s$ 값은 InCMC 값에 대하여 일차함수의 관계를 나타내었다. 그리고 열역학적 고찰을 위하여 온도에 따른 $K_s$ 값의 변화로부터 여러 가지 열역학 함수값(${\Delta}G^0_s$, ${\Delta}H^0_s$ 및 ${\Delta}S^0_s$)을 계산하고 분석하였다.

• 한국결정학회지
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• 제11권1호
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• pp.46-51
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• 2000

The molecular structures of 2-SC₄H₃CH=NN(H)C/sub 6/H/sub 5/(C/sub 11/H/sub 10/N₂S) and (GaMe₂)₂(2-SC₄H₃CH=NNC/sub 6/H/sub 5/)₂(C/sub 26/H/sub 30/Ga₂N₄S₂) have been determined by X-ray diffraction. Crystallographic data for 2-SC₄H₃CH=NN(H)C/sub 6/H/sub 5/:orthorhombic space group P2₁2₁2₁, a=6.108(1)Å, b=7.593(1)Å, c=22.356(2)Å, V=1037.1(3)ų, Z=4, R=0.0613. Crystallographic data for (GaMe₂)₂(2-SC₄H₃CH=NNC/sub 6/H/sub 5/)₂:monoclinic space group P2₁/n, a=15.996(2) Å, c=9.879(3)Å, β=100.07.(2)°, V=2764.599)ų, Z=4, R=0.0503.

• Bulletin of the Korean Chemical Society
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• 제25권7호
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• pp.1012-1019
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• 2004

The synthesis of novel group 9 metal complexes containing the S,S'-chelate ligands, $Li_2S_2C_2B_{10}H_{10}$ (2a) and $LiS(S=PMe_2)C_2B_{10}H_{10$} (2b), is described. Two new dinuclear complexes of the type $[{(cod)M}_2(S,S'-S_2C_2B_{10}H_{10})]$ (cod = 1,5-cyclooctadiene; M = Rh (3a), or Ir (3b)) were synthesized by the reaction of chloridebridged dimers $[M({\mu}-Cl)(cod)]_2$ with one molar equivalent of the corresponding dilithium dithiolato ligand $Li_2S_2C_2B_{10}H_{10}$ (2a). X-ray crystal structure analysis of 3a revealed a dinuclear structure in which each (cod)Rh unit is attached to a distinct sulfur atom of a 1,2-dithio-o-carboranyl ligand (2a). Additionally, the electrochemical properties of 3a and 3b were investigated by cyclic voltammetry. In an analogous manner, reaction of the lithium dithiolato ligand $LiS(S=PMe_2)C_2B_{10}H_{10}$ (2b) with $Cp^{\ast}CoI_2(CO)$ produced a mononuclear dithiolato complex, $[Cp^{\ast}CoI{(S,S'-S(S=PMe_2)C_2B_{10}H_{10})}]$ (4), which was characterized by single-crystal X-ray analysis.

• 한국환경보건학회지
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• 제42권2호
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• pp.112-117
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• 2016

Objectives: In this study, we investigated the biodegradation rates of 8 perfluorooctanesulfonate (PFOS) alternatives synthesized at the at Changwon National University in comparison to those of PFOS potassium salt and PFOS sodium salt. Methods: A biodegradability test was performed for 28 days with microorganisms cultured in the good laboratory practice laboratory at the Korea Environment Corporation following the OECD Guidelines for the testing of chemicals, Test No. 301 C Results: While $C_5H_8F_3SO_3K$, $C_8F_{17}SO_3K$ and $C_8F_{17}SO_3Na$ were not degraded after 28 days, the 3 alternatives were biodegraded at the rates of 31.4% for $C_8H_8F_9SO_3K$, 25.6% for $C_{10}H_8F_{13}SO_3K$, 23.6% for $C_{25}F_{17}H_{32}S_3O_{13}Na_3$, 20.9% for $C_{15}F_9H_{21}S_2O_8Na_2$, 15.5% for $C_{23}F_{18}H_{28}S_2O_8Na_2$, 8.5% for $C_{17}F_9H_{25}S_2O_8Na_2$ and 4.8% for $C_6H_8F_5SO_3K$. When the concentration was the same(500 mg/L), $C_{23}F_{18}H_{28}S_2O_8Na_2$ had the lowest tension with 20.94 mN/m, which was followed by $C_{15}F_9H_{21}S_2O_8Na_2$ (23.36 mN/m), $C_{17}F_9H_{25}S_2O_8Na_2$ (27.31 mN/m), $C_{25}F_{17}H_{32}S_3O_{13}Na_3$ (28.17 mN/m), $C_{10}H_8F_{13}SO_3K$ (29.77 mN/m) and $C_8H_8F_9SO_3K$ (33.89 mN/m). Having higher surface tension of 57.64 mN/m and 67.57 mN/m, respectively, than those of the two types of PFOS salts, $C_6H_8F_5SO_3K$ and $C_5H_8F_3SO_3K$ were found valueless as substitute for PFOS. Conclusion: The biodegradation test suggest that 6 compounds could be used as substitutes for PFOS. $C_{23}F_{18}H_{28}S_2O_8Na_2$ and $C_{15}F_9H_{21}S_2O_8Na_2$ were found to be the best substitutes based on biodegradation rate and surface tension, followed by $C_{25}F_{17}H_{32}S_3O_{13}Na_3$, $C_8H_8F_9SO_3K$ and $C_{10}H_8F_{13}SO_3K$. $C_{17}F_9H_{25}S_2O_8Na_2$ was found to have relatively low value as an alternative but it still had a potential to substitute the conventional PFOS.

• Bulletin of the Korean Chemical Society
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• 제14권1호
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• pp.113-117
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• 1993

Good yield synthetic routes for the production of new B-alkyl-dithiaborane clusters are reported. The syntheses of the B-alkyl-dithiaboranes are based on the use of Fischer-type carbene reagents to activate the B-H bonds of dithiaborane for alkyl-addition reactions and are the first examples of transition-mediated reactions of dithiaborane to be reported. Thus, reactions employing arachno-$S_2B_7H_8$- and $(CO)_5M{C(R_1)R_2}$ (M = Cr, W; $R_1 = CH_3,\;C_6H_5;\; R_2 = OCH_3,\;SC_6H_5)$ were found to yield the intermidiate anions I, $[(CO)_5M{C(R_1)R_2S_2B_7H_8}]^-$, which upon protonation gave the corresponding neutral, air-sensitive cluster arachno-4-$RCH_2-6,8-S_2B_7H_8(R=CH_3,\;IIa;\;C_6H_5,\;IIb)$ range from 30 to 35% yield. Complexes IIa and IIb are isoelectronic with arachno-6,8-$S_2B_7H_9$ and, on the basis of the spectroscopic data, are proposed to adopt a similar arachno cage geometry in which an $RCH_2$ units are substituted to 4 position boron atom of the arachno-6,8-$S_2B_7H_9$.

• 한국식품위생안전성학회지
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• 제33권6호
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• pp.495-499
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• 2018

후춧가루에 존재하는 식중독 균을 저감화시키기 위한 방법으로 UV-C와 mild heat를 병합 처리 가능성을 타진하였다. Escherichia coli O157:H7 (ATCC 35150)와 Salmonella Typhimurium (ATCC 19585)를 후춧가루에 각각 $10^6$, $10^7CFU/g$ 수준으로 인위접종하여 $2.32W/cm^2$의 UV-C와 $60^{\circ}C$의 mild heat을 10분에서 70분 동안 처리하였다. 그 후 미생물 분석 및 후춧가루의 품질변화를 측정하였다. UV-C를 단독으로 70분 동안 처리했을 때 E. coli O157:H7과 S. Typhimurium는 각각 1.89, 2.24 log CFU/g 수준으로 감소하였지만, UV-C와 mild heat을 70분 동안 병합처리 했을 때는 각각 2.46, 5.70 log CFU/g으로 감소하였다. E. coli O157:H7 보다는 S. Typhimurium의 저감효과가 더 컸다. 색도는 모든 처리구에서 유의적인 차이가 없는 것으로 나타났다. 따라서 UV-C와 mild heat 병합처리는 후춧가루에 존재하는 식중독 균을 사멸시키는 데 효과적이기 때문에 산업적인 살균처리 기술로 활용될 수 있을 것으로 판단되었다.

• 대한수학회논문집
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• 제18권3호
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• pp.581-586
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• 2003

The aim of this note is to consider some interesting reducible cases of $H_{A}\;and\;H_{C}$ introduced by Srivastava who actually noticed the existence of three additional complete triple hypergeometric functions $H_{A},\;H_{B},\;and\;H_{C}$ of the second order in the course of an extensive investigation of Lauricella's fourteen hypergeometric functions of three variables.

• Journal of Ginseng Research
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• 제19권1호
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• pp.45-50
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• 1995

(20S)- and (20R)-protopanaxadiol were prepared from crude ginseng saponin by chemical treatment. The $^{1}H$- and $^{13}C$-NMR signals of these compounds were fully assigned by various NMR techniques such as DEPT, 1H-1H COSY, HMQC, HMBC and NOESY.

• KSBB Journal
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• 제4권2호
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• pp.65-68
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• 1989

누에 번데기의 단백질 추출 조건을 규명하고자 온도, ph및 시간 변화에 따라 추출된 단백질의 총 질소함량을 Kjeldahl법과 원소 분석기를 이용한 결과는 다음과 같다. 1. 누에 번데기의 초단백질 : 23.34%, 조지방 : 15.61%이나, 2. 온도 변화에 따른 ph 4에서 1시간 추출시 6$0^{\circ}C$:6.76%, 8$0^{\circ}C$:7.94%, 10$0^{\circ}C$:8.67%이고 C.H.N corder의 분석결과는 6$0^{\circ}C$:8.08%, 8$0^{\circ}C$:9.52%, 10$0^{\circ}C$:9.72%로서 두 가지 방법에서 수치는 다르지만 온도 상승에 따라 수용성 질소계수가 증가하는 경향임을 알 수 있다. 3. pH변화에 따른 8$0^{\circ}C$에서 1시간 추출시 pH 4:7.94%, pH 6:8.96%, pH : 8:9.70%, pH : 10:10.67%, pH : 12:10.98%로 온도 상승과 같이 pH증가에 따라 증가하는 경향을 보이고 있다. 4.추출시간의 변화에 따른 10$0^{\circ}C$에서 pH 4인경우 1시간:8.67%, 2시간:9.23%, 3시간:9.76%이고, C.H.N. corder의 결과는 1시간:9.72%, 2시간:10.06%, 3시간:10.83%로서 추출 시간이 늘어남에 따라 증가되는 경향을 보이고 있다.

• Bulletin of the Korean Chemical Society
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• 제8권1호
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• pp.31-39
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• 1987

By using a complete rate constant($k_e$) which treats a solvent (water) as a reactant, and a conventional rate constant($k_c$), which ignores the solvent in describing the rate, the parameters ${\Delta}V^{\neq}_s,\;{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ were introduced. These quantities represent the volume change, the enthalpy change, and the entropy change accompanying the electrostriction which occurs when solvent molecules condense on the activated complex. The authors measured the rates of the solvolysis of benzoyl chloride in water-acetone mixtures at $15^{\circ}$ to $30^{\circ}C$ and 1 bar to 2500 bars. Applying the authors' theory to the experimental results, the parameters, ${\Delta}V^{\neq}_s,\;{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ were evaluated, and it was found that they are all negative, indicating that water dipoles condense on the activated complex. They also proposed the following equations: ${\Delta}H^{\neq}_c\;=\;{\Delta}H^{\neq}_e\;+\;{\Delta}H^{\neq}_s\;and\; {\Delta}S^{\neq}_c\;=\;{\Delta}S^{\neq}_e\;+{\Delta}S^{\neq}_s\;,\;where\;{\Delta}H^{\neq}_c\;and\;{\Delta}H^{\neq}_c\;and\;{\Delta}S^{\neq}_s $are the activation enthalpy change and the activation entropy change for the conventional reaction rate, respectively, and ${\Delta}H^{\neq}_e$ and ${\Delta}S^{\neq}_e$ are the corresponding quantities for the complete reaction rate. The authors proposed that for the $SN_1$ type, all the quantities, ${\Delta}V^{\neq}_s,\;{\Delta}S^{\neq}_s\;,{\Delta}H^{\neq}_s\;and\;{\Delta}S^{\neq}_s$ are comparatively large, and for the $SN_2$ type, these quantities are smaller than for the $SN_1$ type, and occasionally the case ${\Delta}S^{\neq}_e$ < 0 occurs. Using these criteria, the authors concluded that at high temperature, high pressure and for a high water content solvent, the SN_1$ type mechanism predominates whereas in the reversed case the $SN_2$M type predominates.