• 한국위성정보통신학회논문지
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• 제8권1호
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• pp.45-53
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• 2013

기존의 NEDSCR 소자는 매우 낮은 스냅백 홀딩전압과 낮은 온-저항을 가져 정상적인 동작 동안 래치업을 초래하므로 ESD 보호소자로 사용하는데 어려움이 있었다. 본 연구에서는 NEDSCR 소자의 시뮬레이션 및 TLP 테스트를 통해 이러한 단점들을 극복할 수 있는 새로운 방법을 제안하였다. 매우 우수한 ESD 보호 성능과 높은 래치업 면역 특성을 구현하기 위해 N+ 소오스 확산영역을 둘러싸는 P형의 CPS 이온주입공정을 추가함으로써 NEDSCR 소자의 스냅백 홀딩전압과 온 저항을 증가시켜 정전기 보호 성능을 개선시킬 수 있는 것으로 입증되었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.360-363
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• 2009

In order to improve the overall power conversion efficiency, it is very important to reduce the interface resistance of dye-sensitized solar cells (DSSCs). In this approach, tiny $TiO_2$ nanoparticles with the primary size of 10~20nm were synthesized and deposited between FTO glass and preformed $TiO_2$ layer by $TiOCl_2$ treatment, and also Pt catalysts were deposited on the counter electrode by both ion-sputter and thermal deposition to reduce the electrolyte-counter electrode interface resistance. The influence of these processes on the performace of DSSCs were discussed in terms of fill factor, short circuit current, and conversion efficiency.

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.458-461
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• 1995

The influence of adding counter-ion such as Na+ on the dimerization of the two sulphonated azo dyes, C.I. Acid Red 14 and C.I. Acid Red 17 in aqueous media has been studied spectrophotometrically. The observed hypochromic effect on increasing the amount of salt has been described. The dye concentration range where the dimerization equilibrium is applicable was chosen. No metachromatic behaviour was observed on changing the dye concentration and the amount of salt. This behaviour was attributed to the ability of the counter-ion to disrupt the structure of water as well as reducing the electrostatic repulsion forces between dye anions which will lead to the increase of aggregation tendency of the dye species.

• 한국입자에어로졸학회지
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• 제14권1호
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• pp.17-24
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• 2018

Since the motion of the charged particle strongly depends on its charge characteristics, information on charge distributions of target particles is one of the important variables in aerosol research. In this study, charged distribution of atomized NaCl particles were measured using a Gerdien type ion counter. Two kinds of particle charging conditions were used in this study. First, atomized NaCl particles were passed through an aerosol neutralizer to have a Boltzmann charge distribution, and then its charge distribution was measured. In this case, the portion of uncharged particles was compared with the portion obtained from the Boltzmann charge distribution for verifying the suggested experimental method. Second, same experiment was conducted without the aerosol neutralizer to measure the charge distribution of atomized and un-neutralized NaCl particles. In the conclusion, the portion of uncharged, negatively charged and positively charged particles were 19%, 62% and 20%, respectively, for neutralized particles. The atomized particles, which was generated without the aerosol neutralizer, also had almost a zero charge state, but the standard deviation in charge distribution was larger than that of neutralized particles. The test method proposed in this study is expected to be used in various aerosol research fields because it can obtain simple information on the particle charge characteristics more easily and quickly than the existing test methods.

• Archives of Pharmacal Research
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• 제13권2호
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• pp.174-179
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• 1990

Second derivative (D2) spectrometry using ion-pair extraction technique was development for the determination of total glycyrrhetic acid (GA) in Glycyrrhizae Radix, Glycyr-rhizin (G) obtained from Glycyrrhizae Radix was hydrolyzed into GA in 2 N-HCI and methanol (1:1) and extracted from aqueous phase in the form of an ion-pair complex with tetrapentylammonium bromide (TPA) as a counter ion. Maximum D2 amplitude (Z value) was obtained when 1000-fold or greater molar ratio of TPA was used at pH 11. Reaction an effective extraction solvent of the ion-pair complex. The linearity of standard curve of ion-pair GA was obtained in the range of 4.120 $\mu$g/ml as GA. Assayed contents of GA in dry powder by D2 UV spectrometry and HPLC method were 5.31 $\pm$ 0.04% and 5.20 $\pm$ 0.008%, respectively.

• 분석과학
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• 제10권5호
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• pp.343-349
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• 1997

역상 이온쌍 고성능액체크로마토그래피(RP-IPC)에 의한 살균제 농약 kasugamycin(5-amino-2-methy-6-(2,3,4,5,6-pentahydroxy cyclohexyloxy) tetrahydropyran-3-yl-amino-${\alpha}$-iminoacetic acid)의 정량분석법을 확립하였다. Ksugamycin의 정량분석법을 확립하기 위해 RP-IPC에서 organic modifier의 농도, 용리액의 pH 및 상대이온(counter ion)의 종류와 농도에 의한 시료의 머무름 거동에 대한 영향을 조사 검토하였다. 확립된 최적 변수를 바탕으로 개발된 이 분석법은 kasugamycin의 품질관리에 활용할 수 있음을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1381-1391
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• 2002

The solvent sublation using ion pairs of metal-2-naphthoate(2-HNph) and tetrabutyl ammonium ($TBA^+$) ion has been studied for the concentration and determination of ultra trace Bi(III), In(III) and Tl(Ⅲ) ions in water samples. The partition coefficients ($K_p$) and the extraction percentages of 2-HNph and the ion pairs to methyl isobutyl ketone (MIBK) were obtained as basic data. After the ion pair $TBA^+$·M$(Nph)_4^-$ was formed in water samples, the analytes were concentrated by the solvent sublation and the elements were determined by GF-AAS. The pH of the sample solution, the amount of the ligand and counter ion added and stirring time were optimized for the efficient formation of the ion pair. The type and amount of optimum surfactant, bubbling time with nitrogen and the type of solvent were investigated for the solvent sublation as well. 10.0 mL of 0.1 M 2-HNph and 2.0 mL of 0.1 M $TBA^+$ were added to a 1.0 L sample solution at pH 5.0. After 2.0 mL of 0.2%(w/v) Triton X-100 was added, the ion pairs were extracted into 20.0 mL MIBK in a flotation cell by bubbling. The analytes were determined by a calibration curve method with measured absorbances in MIBK, and the recovery was 80-120%.

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 첨단 분리막 연구동향
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• pp.1-11
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• 2004

Ion-exchange membranes have been widely used in various applications such as diffusion dialysis, electrolysis, electrodialysis, fuel cell etc [1-2]. When an electric current passes through the membrane system, the current is carried by both positive and negative ions in the bulk solution phases, whereas it is carried mainly by the counter-ions in the membrane. (omitted)

• 한국산학기술학회논문지
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• 제3권3호
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• pp.194-197
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• 2002

이온교환은 액체상 이온과 고체상 이온간의 화학반응이며 연수 및 탈염공정, 특정물질의 제거 및 회수, 토양을 통한 이온성 물질의 이동에서 널리 이용되고 있다. 이온 선택도는 원자가가 높을수록, 수화반경이 작을수록 증가한다. 본 연구는 평형 이온교환에서 결정된 이온 선택도가 칼럼 이온교환에 적용되는 가를 조사하였다. 음이온 교환수지에 대한 이온 선택도 순서는 OH/sup -/ < F/sup -/ < HCO/sup -/ < Cl/sup -/ < Br/sup -/ ≤ NO₃/sup -/ < SO₄/sup 2-/ 이였으며, 음이온 칼럼교환에서도 동일하였다. 또한 바탕 양이온의 전하가 낮을수록 이온교환이 빠르게 진행됨을 알 수 있었다.

• 약학회지
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• 제27권2호
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• pp.125-131
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• 1983

Whether ($AB_{w}$) may be neglected against ($A_{w}^{+}$) in the calculation of the extraction coefficient of ion-pairs was criticized by both experiments and theoretical consideration, where ($AB_{w}$) and ($A_{w}^{+}$) mean the molar concentration of ion-pair AB and cation $A^{+}$ in the aqueous phase. Ion-pair complexes were partitioned between phosphate buffer (pH 7.4) and n-octanol. Tetrabutylammonium, isopropamide and methylene blue were selected as cations and benzoic acid, p-toluenesulfonic acid, salicylic acid and taurodeoxycholic acid were selected as counter ions (anions). As a result, conventional methods which assume no existence of ($AB_{w}$) were proven to lack generality. The equation proposed in my earlier report was confirmed to be valid as a general method.