• 한국환경농학회지
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• 제18권4호
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• pp.361-365
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• 1999

본 연구는 우리 나라 콩 장려품종인 검정콩1호를 대상으로 100mM NaCl 처리에 따른 30일묘의 생육특성 및 광합성 반응을 조사하여 다음과 같은 결과를 얻었기에 보고하는 바이다. NaCl stress에 의한 콩 유묘는 뿌리혹이 전혀 형성되지 않았으며, 잎의 건물중이 77.3% 감소로 염해가 가장 크게 나타났으며, 경직경의 감소는 가장 적었다. 그러나 수분함량은 NaCl stress로 증가하였는데 잎이 가장 많은 수분함량을 보였다. 또한 엽위별 엽두께는 NaCl stress로 두꺼워졌으며, 잎의 수분포텐셜은 낮아졌다. 엽록소함량은 NaCl stress로 감소하였으며 생육이 진전됨에 따라 감소되었지만 무처리는 증가하는 경향을 보였다. 광합성, 기공전도도, 증산량 모두 NaCl stress로 감소하였으며 NaCl stress에 의한 엽의별 차이는 적은 것을 알 수 있었다.

• 한국전기전자재료학회논문지
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• 제11권10호
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• pp.758-762
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• 1998

Electrical conduction property of insulator surface is most important factor to assess the insulation performances of outdoor insulating materials. In this paper, contamination performance of the materials to be used for outdoor insulator such as porcelain, EPDM, silicone rubber was discussed by measuring properties of average leakage current and scintillation discharge pulses under salt fog conditions. The fog was applied by nozzle in chamber and fogging fluids were deionized distilled water, 0.5wt% NaCI solution and 2wt% NaCl solution. The average leakage current showed linearly with applied voltage at dry and clean surface condition. The magnitude of leakage current was almost same at different kinds of samples. In case of deionized distilled water fog, the characteristics of leakage current and applied voltage were much different to those in case of dry and clean condition with 2wt% salt fog. In case of slat fog pollution condition, the leakage current was increased above critical voltage. the scintillation discharges were also activated at the level. The leakage current and scintillation discharges were increased with increasing pollution degree. The resistance to pollution properties of silicone rubber appeared excellent among them.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.929-934
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• 2001

The physiological role of brain somatostatin in the central regulation of feed intake in sheep was investigated through a continuous intracerebroventricular (ICV) infusion of somatostastin 1-28 (SRIF) at a small dose of $5{\mu}g/0.2ml/hr$ for 98.5 hours from day 1 to day 5. Sheep (n=5) were fed for 2 hours once a day, and water and 0.5 M NaCI solution were given ad libitum. Feed, water and salt intake were measured during ICV infusion of artificial cerebrospinal fluid (CSF) and SRIF. The feed intake during SRIF infusion on days 2 to 5 increased significantly compared to that during CSF infusion. Water intake, when compared to that during CSF infusion, only increased significantly on day 4. NaCI intake during SRIF infusion was not different from that during CSF infusion. Mean arterial blood pressure (MAP) and heart rate during SRIF infusion were not different from those during CSF infusion. The plasma concentrations of Na, K, Cl, osmolality and total protein during SRIF infusion were also not different from those values during CSF infusion.There are two possible mechanisms, that is, the suppression of brain SRIF on feed suppressing hormones and the direct actions on brain mechanisms controlling feed intake, explaining how SRIF works in the brain to bring about increases in feed intake in sheep fed on hay. The results indicate that brain SRIF increases feed intake in sheep fed on hay.

• 약학회지
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• 제36권6호
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• pp.538-547
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• 1992

Optimal synthetic condition of barium sulfate were investigated from the viewpoint of yield and bulkiness according to a randomized complete block design proposed by G.E.P. Box and K.B. Wilson. Barium chloride and magnesium sulfate were utilized as reactants in order to prepare barium sulfate in this study. It was found that optimum temperature range of reactant solutions was $60{\sim}100^{\circ}C$ and the optimum concentration range of the reactant solutions was $10{\sim}17.3%$ and $10{\sim}20%$ respectively, on the viewpoint of yield and bulkiness. The optimum mole ratio of $BaCI_2$ to $BaSO_4$ was in the range of $1.50{\sim}2.0$ and the optimum mole ratio of $BaCI_2$ to $BaSO_4$ was in the range of $1.50{\sim}2.0$ and the optimum reacting time range was $15{\sim}20$ minutes. The optimum drying temperature range was $110{\sim}130^{\circ}C$ from the viewpoint of yield, but it was $90{\sim}110^{\circ}C$ on the basis of bulkiness. Apparent viscosity of barium sulfate suspensions dispersed in various concentrations of Na. CMC was measured by using Brookfield synchrolectric viscometer model LVT, the relative equation, log ${\eta}_{sp}=A+B.{\phi}$ was examined and the equation was found to agree fairly well. 1 w/v% Na. CMC aqueous solution and 0.1 volume fraction of $BaSO_4$ powder were optimum in the preparation of $BaSO_4$ suspension showing highest viscosity at infinite shearing.

• 한국식품영양과학회지
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• 제24권1호
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• pp.105-113
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• 1995

게 가공 폐기물을 부가가치가 높은 키틴 자원으로 활용코자, 이들 폐기물로 부터 키틴을 효율적으로 분리할 수 있는 조건을 설정하고 이로 부터 제조된 키틴의 물리화학적 성질을 조사하였다. 탈회분은 원료중량의 15배에 해당하는 1N HCI로 실온에서 30분간 교반함으로서, 탈단백질은 탈휘분된 시료에 원료중량의 15배에 해당하는 5% NaOH용액으로 $65^{\circ}C$에서 1시간 동안 교반함으로서 가장 효율적으로 이루어졌다. 탈색소는 원료중량의 10배에 해당하는 0.32% NaOCI로 3분간 처리시 가장 바람직하였다. 침지에 의한 탈회분 및 탈단백질은 교반에 비해 추출 효율성이 낮고 장시간을 요하였다. 백색의 최종 키틴제품은 질소함량이 6.45%, 회분은 0.15%이었으며, 5% lithium chloride를 함유한 N,N-dimethylacetamide-용액(DMAc-5% LiCI)에서 0.1% 키틴의 점도는 12.8cP를 나타냈다. 또한 DMAc-5% LiCI에서 키틴의 용해도는 58.4%를 나타냈으며, bulk density는 입자 크기가 20~40mesh 일때 0.27g/ml, 100mesh 이하일 때는 0.43g/ml를 나타내었다. 입자 크기에 따른 키틴의 질소 및 회분함량에는 별 차이가 없었으며, 키틴의 수율은 입자의 크기가 클수록 증가하는 경향이었다. 키틴 제조시 탈색공정은 키틴의 점도를 감소시켰으며 용해도에는 별 영향이 없었다.

• 대한기계학회논문집
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• 제11권6호
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• pp.867-876
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• 1987

본 연구에서는 보통강재인 SS 41 강을 열처리하여 얻은 M.E.F.복합조직강의 모상입경변화와 3.5% NaCl수용액의 pH변화 조건하에서 반복굽힘피로실험을 하여 부식 피로파괴에 미치는 영향에 대해 고찰하였다.

• 대한기계학회논문집
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• 제17권6호
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• pp.1404-1411
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• 1993

본 연구는 오스템퍼링 온도와 유지시간을 변화시켜 오스템퍼링 한 저합금구 상흑연주철을 실험재로 하여 증류수 및 NaCI수용액 중에서의 부식마멸특성 및 그 기구 를 규명하여 Tribology 설계에 대한 자료를 제시하는 것을 목적으로 하였다.

• 한국재료학회지
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• 제6권10호
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• pp.1025-1033
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• 1996

본 연구에서는 0.5M NaCI 용액내에서 일어나는 고분자재료로 피복된 강의 퇴화현상을 광학현미경 관찰 및 A.C. impedance spectroscopy를 이용하여 연구하였다. 강의 부식은 고분자재료로 피복된 강의 경우 국부부식(localized corrosion)의 형태로 나타난 반면, 피복되지 않은 강의 경우에는 전면부식(uniform corrosion)의 형태로 진행되었다. 고분자재료로 피복된 강의 부식이 국부적으로 진행되는 것은 피복층내에 존재하는 기공이나 크랙과 같은 결함 등에서 부식이 선택적으로 일어나기 때문으로 사료된다. 피복층의 박리(delamination) 현상은 고분자재료로 피복된 강/구리 갈바닉쌍(galvanic couple)의 경우 구리표면 위의 피복층에서만 관찰되었다. 이는 캐소드(cathode)로 작용하는 구리의표면에서 산소의 환원반응에 의해서 형성된 수산화이온(OH-)이 피복층의 박리를 조장하고 있음을 보여준다. 또한, 고분자재료 피복층의 파손 현상은 고분자재료/강의계면에서 석출된 부식생성물에 의해서 크게 조장되고 있음을 알 수 있다.

• 한국세라믹학회지
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• 제42권7호
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• pp.461-468
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• 2005

Transparent TiO$_{2}$ sols were prepared by hydrothermal synthesis to heat Ti precursor solutions, from Ti hydroxides obtained with neutralizing aqueous TiOCl$_{2}$ solutions having various concentrations of NaCI by aqueous NaOH solution, in the autoclave at 120$^{\circ}C$ The photocatalytic abilities of glass beads coated with the sol for gaseous benzene were evaluated. As a result, it was found that due to the increase of brookite phase in TiO$_{2}$ by controlling the concentration of Na ion the optical absorption of TiO$_{2}$ increases toward long wavelength but that in the area of short wavelength becomes relatively low and consequently the photocatalytic performance of TiO$_{2}$ thin film for benzene gas rather decreases, compared to that of composite film of anatase and brookite phases. These results suggest that in order for coated TiO$_{2}$ thin film to have high dissociation performance for benzene gas it is effective to form anatase and brookite phases compositely in TiO$_{2}$.

• Environmental Engineering Research
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• 제22권3호
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• pp.312-319
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• 2017

The treatment of dyeing wastewater is not easy because dyes are mainly aromatic, heterocyclic compounds. The most effective technologies and methods to treat dyeing wastewater are costly and involve materials that are difficult to regenerate after use. Therefore, it is necessary to develop cost-effective, eco-friendly technologies to treat dyeing wastewater. The aim of this study was to investigate the removal of sulfur blue 11 (CI 53235) anionic dye using methyl esterified sericite (ME-sericite) adsorbents in an aqueous solution. The results are discussed in terms of the ME-sericite particle size, temperature, pH value and initial sorption rate according to the initial sulfur blue concentration. In addition, we analyzed the adsorption kinetics using a Pseudo-second-order model with the desorption and reusability. The methyl esterification caused a considerable increase in the specific surface area from 4.45 to $17.62m^2/g$. The ME-sericite adsorbents successfully removed > 98% of the sulfur dye in the aqueous solution. For the adsorption of 1 mg of sulfur dye, approximately 4.6 to 6.6 g/L ME-sericite were required. The desorption process was carried out by mixing a NaOH eluent to desorb 90.56% of the sulfur dye with 2 h of contact time. Thus, the ME-sericite is a promising adsorbent to treat dyeing wastewater due to its low dose requirement, high removal efficiency and inexpensive material.