• 대한화학회지
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• 제39권12호
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• pp.910-917
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• 1995

단일컬럼 이온 크로마토그래피에서 $F^-,Cl^-,NO_2^-,NO_3^{2-}$의 다섯 가지 음이온에 대한 최적 분리 조건과 분석 시간에 대하여 연구하였다. 프탈산 용리액에서 용리액의 농도를 2.0에서 3.5mM까지, 용리액의 pH를 3.5에서 4.5까지 변화시킨 결과 2.0mM pH 4.5가 가장 최적 조건임을 알 수 있었다. 용리액의 농도 및 pH가 증가할수록 용리강도는 증가하였고 음이온들은 $F^-,Cl^-,NO_2^-,NO_3^{2-}$ 및 $SO_3^2-$순으로 모두 10분이내로 바닥선 분리되어 용리하였다. 또한 이 조건에서 다른 조건보다 검출기 감도가 비록 감소하였으나 시스템 봉우리가 분석에 영향을 미치지 않을 정도로 감소하였기 때문에 연속분석시 분석 시간을 약 40% 단축할 수 있었다. 이 조건하에서 다섯 가지 음이온의 검정 곡선은 모두 상관 계수가 0.999 이상이었으며 9종의 시판 생수를 분석하였다.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1734-1740
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• 2012

Voltammetric characterization of hydrophilic anion transfer processes across a 66 microhole array interface between the water and polyvinylchloride-2-nitrophenyloctylether gel layer is demonstrated. Since the transfer of hydrophilic anions including $Br^-$, $NO_3{^-}$, $I^-$, $SCN^-$ and $ClO_4{^-}$ across the liquid/gel interface usually sets the potential window within a negative potential region, a highly hydrophobic organic electrolyte, tetraoctylammonium tetrakis(pentafluorophenyl)borate, providing a wider potential window was incorporated into the gel phase. The transfer reaction of perchlorate anions across the microhole-water/gel interface was first studied using cyclic voltammetry and differential pulse voltammetry. The full voltammetric response of perchlorate anion transfer was then used as a reference for evaluating the half-wave transfer potentials, the formal transfer potentials and the formal Gibbs transfer energies of more hydrophilic anions such as $Br^-$, $NO_3{^-}$, $I^-$, and $SCN^-$. The current response associated with the perchlorate anion transfer across the micro-water/gel interface versus the perchlorate concentration was also demonstrated for sensing applications.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.759-761
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• 2006

The compound B(C6F5)3 and its variations have been widely employed as alkyl carbanion abstracting reagents to produce metallocene cations for olefin polymerization.1-3 Weakly coordinating anions containing boron can greatly improve the activity of metallocene catalysts used in industrial olefin polymerization4 and thus group IV and V metallocene complexes of the organohydroborate anions have been intensively investigated.5 Recently, many organohydroborate metallocene complexes have been reported by Shore and co-workers.6-8 A common structural feature of those complexes is the three-center two electron M-H-B bond, like that observed in transition metal tetrahydroborate complexes but the reactivity and fluxional behavior of organohydroborate complexes are unlike those of the tetrahydroborate analogues.6 Although many of those metallocenes have been synthesized, few complexes could be used in the olefin polymerization and then this laboratory has been involved in the chemistry of the cyclic organohydroborate anions, and their group IV metallocene derivatives for the catalyst.9 Described here is recent work that led to the preparation of a novel cyclic organohydroborate hafnocene complex (h5-C5H5)2Hf ？(μ-H)2BC8H14 ,Cl. The hafnocene complex contains the three-center two electron bond Hf-H-B10 in which the hydride abstraction for olefin polymerization may occur.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.489-492
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• 2000

발효액으로부터 유산을 정제하기 위해서 나노여과를 이용할 때, hardness의 제거효율은 발효액내 이온성분의 분포와 밀접한 관련이 있다. 특히 음전하를 띠고 있는 막의 경우, 용액내 이가 음이온에 의해서 모든 이온들이 영향을 받으며 일가 음이온의 반발력은 거의 없는 것으로 관찰되었다. 따라서 발효액내 일가 음이온의 양을 줄이거나 더 높은 전하밀도를 가진 막을 사용한다면 나노여과를 이용하여 발효액내 hardness를 효과적으로 제거할 수 있으리라 생각된다.

• Environmental Analysis Health and Toxicology
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• 제24권4호
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• pp.293-301
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• 2009

This study was conducted to investigate the distribution of the concentrations of selected trace metals and inorganic anions in five types of drinking water samples (mineral spring water, well water, small community water, municipal tap water, and commercial mineral water) collected from Chuncheon, Gangwon-do in 2007. Forty four samples were analyzed for five metals and five anions using an atomic absorption spectrometer and an ion chromatograph, respectively. Arsenic (As) and nitrate (${NO_3}^-$) concentrations in some groundwater samples did not meet the future (10 ${\mu}g/L$) and current (44 mg/L) Korean drinking water standards, respectively. On the other hand, any municipal tap water samples, the sources of which were lake surface water, satisfied the Korean standards. Human health risk assessment results showed that arsenic in all types of water, especially groundwater including commercial mineral water, may pose both noncarcinogenic and carcinogenic effects on the residents. It is concluded that groundwater is not safe drinking water any longer and that a national survey and follow-up measures need to be taken.

• Korean Chemical Engineering Research
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• 제46권2호
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• pp.436-442
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• 2008

수용액에서 음이온을 제거하기 위하여 다양한 종류의 유기/무기 복합음이온교환수지를 제조하였다. 제조된 음이온교환수지들은 질소흡탈착 실험, 적외선분광실험, 원소분석 등을 통하여 그 특성을 조사하였다. 또한 제조된 음이온교환수지의 음이온 교환 특성을 조사하기 위하여 배치(batch) 실험과 키네틱(kinetic) 실험을 수행하였다. 제조된 시료들 가운데 트리메틸암모늄 기능기를 사용했을 때보다 트리부틸암모늄 기능기를 사용하였을 때 더욱 큰 흡착량을 나타내었는데, 이것은 호프마이스터 효과와도 부합된다. 또한, 소수성기를 다량 보유하고 있는 계면활성제인 헥사데실아민도 소수성 음이온에 대한 교환능이 있는 것을 알 수 있었다.

• 한국대기환경학회지
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• 제11권3호
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• pp.245-252
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• 1995

Atmospheric aerosols were collected by a High Volume Tape Sampler from March 1992 to December 1993 ar Korean, Cheju, Korea. The water soluble ion concentrations in aerosol were analyzed. The concentrations of cations (N $a^{+}$, $K^{+}$, $Ca^{2+}$, $Mg^{2+}$, N $H_{4}$$^{+}$) were determined by an Inductively Coupled Plazma(ICP) or an Atomic Absorption Spectrometer(AAS), and those of anions (C $l^{[-10]}$ , N $O_{3}$$^{[-10]}$ , S $O_{4}$$^{2-}$) were analayzed by the capillary electrophoresis method. The $Ca^{2+}$, S $O_{4}$$^{2-}$ and N $O_{3}$$^{[-10]}$ concentrations in spring were higher than those in other seasons. The lowest concentrations of these elements were found in summer, largely due to scavenging by frequent rains. Especially the $Ca^{2+}$ concentration on April was three to four times higher than the annual mean concentration. The enrichment factor(E.F.) of each element was calculated. The annual mean E.F. values of the $Ca^{2+}$, $Mg^{2+}$ and C $l^{[-10]}$ in 1992 were the same as those in 1993 except $k^{+}$ and S $O_{4}$$^{2-}$. The correlation formula between all cations and anions for the whole period was Anions = 0.759 * Cations + 0.066.Cations + 0.066.

• Bulletin of the Korean Chemical Society
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• 제26권1호
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• pp.57-62
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• 2005

The potentiometric responses for various anions are investigated with membrane electrode (membrane 1) based on 1,3-diethyl-1,3-dihydroxy-1,3-bis(2-dimethylaminomethyl ferrocenyl) disiloxane. The nitrate ion-selective electrode based on compound 1 gave a good Nernstian response of 58.18 mV per decade for nitrate with the detection limit of −e5.66 of log [NO3−e]. Compound 1 has all those functional groups and the other two compounds have less functional group of ferrocenyl or ferrocenyl and hydroxide, respectively. Even though, potentiometric response to anions was excellent at pH 5, the selectivity pattern for all three membrane electrode based on series of disiloxane is almost like Hofmeister sequence at pH 5. However, the membrane electrode 1-3 exhibited very different response to anions at pH 7. In this pH, NH2 is not protonated and ionophore may act as neutral carrier. Hydrogen bond may enhance the responsibility to hydrogen acceptors and intramolecular electro-active site may increase the permeability of analyte to ionophore in membrane.

• 대한화학회지
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• 제32권2호
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• pp.113-121
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• 1988

역상 액체 크로마토그래피에 의한 방향족 슬폰산 및 카르복시산들의 머무름 기구와 분리를 브롬화 도데실트리메틸 암모늄(DTAB)을 포함하는 이동상에서 연구하였다. 머무름 기구는 DTAB가 정지상에 일차층을 형성하고 반면 음이온 시료와 이동상에 존재하는 다른 공존 음이온들이 경쟁적으로 이차층을 형성하는 이온-상호작용 모델임을 확인하였다. 시료들의 용량인자들은 pH, 여러 유기 용매들의 농도, 이동상에 존재하는 공존 음이온 및 시료의 작용기 등 여러 인자들에 의해 영향을 받았다. 그리고 몇 가지 유기 혼합시료들을 최적 조건하에서 상호 분리를 시도하였다