• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.143-149
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• 1990

A sol-gel processing of $YBa_2Cu_3O_{7-x}$ superconductor using metal nitrate salts and sodium hydroxide as the starting materials has been investigated because of the need to produce pure, hompgeneous superconducting materials. Since the precipitation of barium hydroxides can be obtained only at high basicities, the process has to be carried out Ca. pH 13 to get the simultaneous coprecipitation with the other metal hydroxides. The involved reaction mechanisms were investigated and intermediate and final products were characterized by means of thermogravimetric analysis(TGA), infra-red(IR) spectroscopy, X-ray diffraction(XRD) analysis, scanning electron microscopy(SEM), thermal mechanical analysis(TMA) and electrical measurement.

• Journal of Electrochemical Science and Technology
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• 제11권1호
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• pp.41-49
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• 2020

In this study poly(carbazole) films deposited on stainless steel have been investigated as electrode material for supercapacitor applications. Poly(carbazole) films were electrodeposited using cyclic voltammetry in presence of lithium, sodium and tetrabutylammonium perchlorate salts. Poly(carbazole) films doped with perchlorate anions having different counter cations were characterized by SEM, ATR-FTIR and solid state conductivity measurements. Capacitive behaviours of PCz coated steel electrodes were tested by cyclic voltammetry, charge-discharge analysis and electrochemical impedance spectroscopy. It was found that counter cation of the dopant is significantly effective on the capacitive performance on the obtained PCz films and the PCz film synthesized from lithium perchlorate has the better capacitive performance than the poly(carbazole)s synthesized from sodium perchlorate and tetrabutylammonium perchlorate salts.

• 대한화학회지
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• 제13권4호
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• pp.317-324
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• 1969

Isopolytungstic acid and it's salts, which are formed in sodium tungstate solutions, when acidified with perchloric acid, have been investigated by cryoscopic method. The results obtained are summarized as follows; It was not possible to measure the molecular weight of sodium isopolytungstates which are salthydrates, by means of cryoscopic method. Regardless of the concentration of solution, paratungstate and acid hexatungstate are formed at $H^+/WO_4^{2-}$ ratio of 1.15 and 1.50. It has been shown that isopolytungstic acid and it's salts are also formed at $H^+/WO_4^{2-}$ ratio of 1.30 and 1.90 and in highly concentrated solutions at 1.40 and 1.65.

• Applied Biological Chemistry
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• 제38권5호
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• pp.376-381
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• 1995

내열성 alkaline phosphatase의 탐색을 위해 극도호열균중에서 Thermus caldophilus GK24 균주를 선정하였다. 이 균주를 이용하여 basal salts에 sodium glutamate, bactotryptone, glucose 및 yeast extract를 첨가시킨 배지에서 alkaline phosphatase 생산을 검토하였다. 그 결과 sodium glutamate가 alkaline phosphatase 유도에 효과적인 것으로 판명되었다. Alkaline phosphatase 생산을 위한 최적유도용 배지는 basal salts에 0.3% sodium glutamate, 0.2% bactotryptone, 0.5% glucose를 첨가한 것으로 효소활성은 기본배지보다 약 6배, 표준배지 보다는 약 27.5배 증가하였다. T. caldophilus GK24 alkaline phosphatase는 유도효소로 판명되었다. 무기인산 결핍시에 효소가 생산되며, 생육배지에 무기인산을 첨가하면 효소합성에 저해효과가 있었다.

• 한국재료학회지
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• 제16권3호
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• pp.193-197
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• 2006

The sodium/sulfur(Na/S) battery has many advantages such as high theoretical specific energy(760Wh/kg), and low material cost based on the abundance of electrode material in the earth. It has been reported that the electrochemical properties of sodium/sulfur cell above $300^{\circ}C$, utilized a solid ceramic electrolyte and liquid sodium and sulfur electrodes. A lot of researches have been performed in this field. Recently, Na/S battery system was applied for electricity storage system for load-leveling. One of severe problems of sodium/sulfur battery was high operating temperature above $300^{\circ}C$, which could induce the explosion and corrosion by molten sodium, sulfur and polysulfides. In order to develop sodium battery operated at low temperature, sodium ion battery has been studied using carbon anode, and sodium oxides cathodes. However, the energy densities of the sodium ion batteries were much lower than high temperature sodium/sulfur cell. In this study, the sodium/sulfur battery with 1M $NaCF_3SO_3$ is tested at room temperature. The charge-discharge mechanism was discussed based on XRD, DSC, SEM and EDS results.

• Archives of Pharmacal Research
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• 제18권4호
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• pp.231-236
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• 1995

Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excisicylic acid were investigated. In-vitro experiment using a Franze-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inoraganic anions were rougly proportional to lyotropic Hofmeister serlling abilities of the anions l F/sup -/

• 한국표면공학회지
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• 제55권6호
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• pp.460-468
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• 2022

Due to its high electrical conductivity, low contact resistance, good weldability and high corrosion resi-stance, gold is widely used in electronic components such as connectors and printed circuit boards (PCB). Gold ion salts currently used in gold plating are largely cyan-based salts and non-cyanic salts. The cya-nide bath can be used for both high and low hardness, but the non-cyanide bath can be used for low hardness plating. Potassium gold cyanide (KAu(CN)₂) as a cyanide type and sodium gold sulfite (Na₃[Au(SO)₃]₂) salt as a non-cyanide type are most widely used. Although the cyan bath has excellent performance in plating, potassium gold cyanide (KAu(CN)₂) used in the cyan bath is classified as a poison and a toxic substance and has strong toxicity, which tends to damage the positive photoresist film and make it difficult to form a straight side-wall. There is a need to supplement this. Therefore, it is intended to supplement this with an eco-friendly process using sodium sulfite sodium salt that does not contain cyan. Therefore, the main goal is to form a gold plating layer with a controllable hardness using a non-cyanide gold plating solution. In this study, the composition of a non-cyanide gold plating solution that maintains hardness even after annealing is generated through gold-palladium alloying by adding thallium, a crystal regulator among electrolysis factors affecting the structure and hardness, and changes in plating layer structure and crystallinity before and after annealing the correlation with the hardness.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.73-83
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• 1994

Applications of liposomes as a drug carrier for the oral delivery of poorly-absorbable macromolecular drugs have been limited, because of their instability in gastrointestinal environments including pH, bile salts, and digestive enzymes. Two polysaccharides, dextran(DX) and pullulan(PL), were introduced to the preformed liposomes in order to enhance the stability. Palmitoyl derivatives of polysaccharides, palmitoyldextran(PalDX) and palmitoylpullulan(PalPL), were synthesizd and introduced to the liposomes during preparation for the same purpose of stability. The effects of these polysaccharides coating were evaluated basically by physical properties of particle size distribution and optical microscopy, then compared with uncoated liposomes by the observations of both in vitro stability and in vovo absorption characteristics. The geometric mean diameters of polysaccharide-coated liposomes were greater than that of uncoated liposome, showing the outermost polysaccharide-coated layer under the optical microscopy. In vitro stabilities of uncoated or polysaccharides-coated liposomes were measured by turbidity changes in various pH buffer solutions containing sodium choleate as bile salts. While uncoated liposome was very sensitive to bile salts, polysaccharides-coated liposomes were stable in relatively higher concentrations of sodium choleate, giving the results of better stability of PalDX- and PalPL-coated liposomes than that of DX- and PL-coated liposomes. After liposomal encapsulation of acyclovir(ACV), an antiviral agent as a model drug, it has been administered orally to rats as dose of ACV 40 mg/kg. Plasma concentrations of ACV were assayed by HPLC and analyzed by model-independent pharmacokinetics. Pharmacokinetic parameters of Cmax, tmax, and [AUC] have been compared.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.665-670
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• 2003

우라늄 변환시설 내의 lagoon 슬러지의 처리 공정에서 발생하는 고농도 질산염 폐액의 처리를 위해 질산염 폐액의 열역학 및 열분해 특성을 조사하였다. 열역학적 특성은 고농도 질산염 폐액의 조성을 바탕으로 COACH와 GEMINKI II를 사용하여 조사하였으며, 열분해 특성은 TG/DTA, XRD 분석을 통하여 실제 질산염 폐액에 대하여 조사하였다. 폐액 내 함유 성분 중 $NH_4NO_3$는 $^250{\circ}C$에서 모두 분해되었으며, 잔류물의 대부분을 차지하는 $NaNO_3$는 $730^{\circ}C$에서 분해되는 것으로 나타났다. $NaNO_3$의 분해생성물인 불안정한 $Na_2O$를 안정한 화합물로 변화시켜 주기 위하여 $Al_2O_3$를 첨가할 경우 $NaNO_3$는 $450^{\circ}C$의 낮은 온도에서 분해 가능하였다. 이 같은 열역학 및 열분해 특성을 바탕으로 고농도 질산염 폐액의 처리 공정도를 제시하였으며, 특성 자료는 공정 모사의 기초 자료로 활용될 것이다.

• 한국식품조리과학회지
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• 제28권4호
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• pp.363-374
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• 2012

Quality characteristics of baechu (Kimchi cabbage) kimchi prepared using various kinds of domestic solar salts (KS5Y, KS2Y, KS1Y, KFS, and KSS) and imported solar salts (AS1Y and CS1Y) were compared with Korean processed salt (KRS) and Mexican rock salt (MR1Y) during 60 days of storage. Sodium contents of MR1Y, AS1Y, and domestic KRS with values of 363,653.40, 358,952.40, and 356,799.90 mg/dL, respectively, were significantly higher than that of KFS with a value of 280,249.80 mg/dL (p < 0.001). Thus, the kimchi using KFS was expected to have 22-23% lower sodium content compared to that of the other kimchis. KFS magnesium content was significantly highest at 4,464.10 mg/dL and calcium was significantly the highest in samples of KS1Y with a value of 711.31 mg/dL. Most of the pHs and acidities in the kimchi samples were in the optimum range due to the relatively low storage temperature of $2^{\circ}C$. The salt concentrations of all kimchis using domestic solar salt during storage was greatly reduced compared to those using the imported salts or KRS. Sensory saltiness of the KS1Y sample group was significantly the lowest value (6.08) at 0 days of storage (p < 0.001) and maintained relatively low saltiness during the entire storage period. The crispness of the KS2Y, KS1Y, and KSS sample groups were significantly higher (10.02, 9.77, and 9.49, respectively), compared to that of KRS (7.64) at 60 days of storage (p < 0.001). The KFS sample group had the higher acceptance values for pickled seafood aroma, sour aroma, saltiness, and overall acceptability compared to those in the other samples.