• 한국염색가공학회지
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• 제12권4호
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• pp.248-255
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• 2000

Polyester fibers and fabrics have been dyed with disperse dyes in alkaline dyebath such as alkaline buffer and alkaline auxiliary(JPH-95) comparing a traditional acidic dyeing. After dyeing the samples were extracted with 100% DMF, and washing and rubbing fastnesses were measured. In dyeing at $100^\circ{C}$ the dyeing rate increased with decreasing fiber denier, regardless of dye baths, whereas the dyeing rates of the same denier fiber increased in the order of alkaline dyeing>acidic dyeing>JPH-95 dyeing. In dyeing at $130^\circ{C}$ the dyeing rate of PET fiber in JPH-95 dye bath decreased compared with the other two types of dye baths. In the time and temperature curve the dye uptake of JPH-95 dyeing was higher than the other two types of dye baths in the range of low temperature$(95~115^\circ{C})$. The equilibrium dye uptake increased in the order of 0.52d>2.04d>0.05d fiber. Washing fastness had no change in all three types of dye baths. But rubbing fastness was not good for alkaline dyeing except black dyes.

• Journal of Electrochemical Science and Technology
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• 제12권3호
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• pp.302-307
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• 2021

Polymer electrolyte membrane (PEM) electrolyzer or alkaline electrolyzer is required to produce green hydrogen using renewable energy such as wind and/or solar power. PEM and alkaline electrolyzer differ in many ways, instantly basic materials, system configuration, and operation characteristics are different. Building an optimal water hydrolysis system by closely grasping the characteristics of each type of electrolyzer is of great help in building a safe hydrogen ecosystem as well as the efficiency of green hydrogen production. In this study, the basic operation characteristics of a kW class alkaline water electrolyzer we developed, and water electrolysis efficiency are described. Finally, a brief overview of the characteristics of PEM and alkaline electrolyzer for large-capacity green hydrogen production system will be outlined.

• 한국식품저장유통학회지
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• 제11권2호
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• pp.227-232
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• 2004

• 한국염색가공학회지
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• 제6권2호
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• pp.10-16
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• 1994

Neutral salts have negative or positive effects on the rates of many chemical reactions and also on the rates of acidic and alkaline hydrolysis of carboxylic esters. The direction of neutral salt effects on the hydrolysis of ester depends on the charge of esters. Neutral salts accelerate alkaline hydrolysis of esters with negative charge, but decelerate alkaline hydrolysis of esters with positive charge, and have little effect on the alkaline hydrolysis of neutral esters. It is expected that the rate of the alkaline hydrolysis of Poly(ethylene terephthalte) (PET), polymeric solid carboxylic polyester with carboxyl end group at the polymer end, is also influenced positively by neutral salts. In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different anions like NaF, NACl, NaBr, NaI were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the decrease in the nucleophilicity of anions of neutral salts, i.e., in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. It was thought that the reaction rate was increased in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. because the completion of anions with $OH^-$ for carbonyl carbon became weaker with the decrease in the nucleophilicity and with the increase in the size of anions.

• 대한기계학회논문집A
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• 제40권9호
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• pp.767-773
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• 2016

산 및 알칼리 용액 속에 침지한 SiC 세라믹의 기계적 특성은 와이블 통계로 해석하였다. 시험편은 1373K에서 열처리를 행하였다. SiC의 부식은 KSL1607 방법에 의한 산 및 알칼리 용액 속에서 수행하였다. 부식된 균열치유재의 굽힘 강도는 부식되지 않은 균열치유재의 굽힘강도보다 산 및 알칼리 용액 속에서 각각 47% 및 70% 감소하였다. SiC 세라믹의 부식은 산 용액 속에서보다 알칼리 용액 속에서 더 빨랐다. 척도 파라미터 및 형상 파라미터는 모재와 부식재에서 평가하였다. 산 및 알칼리 용액에서 부식된 모재의 형상 파라미터는 산용액에서 크게 나타났다. 그러나 열처리재는 산용액에서 크게, 알칼리 용액에서 작게 나타났다. 모재 및 열처리재의 척도 파라미터는 산 및 알칼리 용액에서 모두 작게 나타났다.

• 한국동물학회지
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• 제36권3호
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• pp.425-432
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• 1993

Culex pipiens pallens에 존재하는 Alkaline phosphatase의 연구를 위한 적정 분석조건과 우화 후, 시간 경과에 따른 Alkaline phosphatase 활성 경향에 대해서 연구하였다. C. pipiens에 존재하는 Alkaline phosphatase의 활성은 우화 직후부터 지속적으로 감소하다가, 흡혈 자극에 의해서 급격하게 증가한다. 흡혈 후 30시간이 경과했을 때, 최대의 활성도를 보이고 감소하나, 흡혈 48시간 이후에는 다시 증가하여 지속적으로 유지됨을 알 수 있다. 기관별 분석에서 첫번째 활성 증가는 중장에서 일어나고, 두번째 활성 증가는 난소에서 일어남을 알 수 있다. 그리고 흡혈 후 30시간된 성체에서는 5개의 동위효소 밴드가 보이는데, 난소에서 ALP-1와 ALP-2가 나타나고, 가슴에서는 ALP-3, ALP-4와 ALP-5가 보인다. 지방체에서는 ALP-4와 ALP-5가, 중장에서는 ALP-3, ALP-4와 ALP-5가 나타남을 알 수 있다. 그리고 흡혈 후 72시간된 성체에서, ALP-1, ALP-2가 동일하게 존재함을 알 수 있다.

• Applied Biological Chemistry
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• 제43권3호
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• pp.169-173
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• 2000

저온에서 높은 세척력을 갖는 호소세제의 개발을 위하여 토양으로부터 alkaline protease의 활성이 높은 균주를 분리, 동정하였으며, 호소의 성질을 조사하였다. 분리균주의 형태적 특징은 Gram 음성균 이고, 간균$(0.6{\sim}0.7{\times}1.3{\sim}2.6\;{\mu}m\;in\;size)$ 형태를 하고 있으며, 운동성을 보였다. 또한 catalase 양성, aesculin, gelatin 및 casein 분해능이 있었다. 분리균주의 세포벽 구성 성분은 meso-DAP를 함유하였으며, G+C mol 함량은 43.3%를 나타내었다. 이러한 형태적, 생리 생화학적 특성의 결과로부터 분리 균주는 Acinetobacter 속으로 동정되었다. 분리 균주를 이용한 alkaline protease의 생산은 초기 pH 10과 $40^{\circ}C$에서 36시간 배양하였을 때 3,300 D.U/mL로 최대 효소 활성을 보였으며, 최적 pH와 온도는 9와 $60^{\circ}C$이었다. 또한 본 균주에 의해 생산된 alkaline protease는 두개의 활성 band를 나타내었다.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.529-538
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• 2010

Proline accumulates in plants under environmental stresses including saline stress and alkaline stress. Here, we investigated the responses to two different stresses, saline stress (200 mM NaCl) and alkaline stress (100 mM $Na_2CO_3$) in two Leymus chinensis (Trin.) genotypes, LcWT07 and LcJS0107, and effects of exogenous proline on the activities of antioxidant enzymes. Both saline stress and alkaline stress significantly induced the accumulation of proline in leaves of the two genotypes after 96 h, and alkaline stress caused a transient and significant increase in LcJS0107 plants at 6 h. A reduction in the activities of catalase (CAT, EC 1.11.1.6) and ascorbate peroxidase (APX, EC 1.11.1.11), but not in the activity of superoxide dismutase (SOD, EC 1.15.1.1), was detected in plants exposed to saline and alkaline stresses. Remarkable decrease in relative water contents (RWC) was found in 144 h stressed plants. However, lipid peroxidation estimated by malonyldialdehyde (MDA) content in leaves remained relatively stable. With the addition of exogenous proline, it did not cause changes of proline levels in two genotypes, but combined with saline or alkaline stress, the exogenous application of proline significantly induced proline accumulation after even short treatment periods. Combined with salt stress, the exogenous application also increased the activities of CAT and APX. These results indicated that exogenous proline not only increases proline levels in vivo as a osmotic adjustment under stress, but mitigates the detrimental effects of saline and alkaline stresses by increasing the activities of antioxidant enzymes.

• 한국동물학회지
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• 제12권3호
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• pp.77-84
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• 1969

著者는 白色레그혼의 種卵을 孵化시켜 얻은 鷄胎中 賢과 後賢에 있어서의 alk. p., PAS-陽性物質 및 燐脂質의 消長과 局在位置의 變異를 組織化學的 方法으로 追究하여 다음과 같은 結果를 얻었다. 1. 分泌尿細管의 器官形成에 앞서 未分化 間葉組織內에 强한 alk. p. 活性이 出現하였으며 同活性은 分泌尿細管의 分化와 함께 消失하였다. 2. 中賢 및 後賢 分泌尿細管의 分化와 함께 alk. p. 및 PAS-陽性物質은 分泌尿細管의 刷子綠에 强陽性反應을 보였다. 3. 中賢 및 後賢 分泌尿細管의 細胞質과 刷子綠은 强한 燐脂質 陽性反應을 띠었다. 4. 造賢組織의 分化中 未分化 間葉組織에 alk. p. 活性이 出現하였다가 組織의 分化와 함께 消失된 事實에서 보아 alk. p. 는 組織分化에 關與하는 것으로 생각된다. 5. 中賢 및 後賢 分泌尿細管의 刷子　 에 있어서 alk. p. 와 PAS-陽性物質 및 燐脂質의 變異와 分布狀態가 一致한 것으로 보아 alk. p. 는 炭水化物의 再吸收 및 燐脂質代謝에 關與하는 것으로 思料된다.

• 한국세라믹학회지
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• 제47권3호
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• pp.216-222
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• 2010

Portland cement has been restricted in applications to ecological area because of its environmental harmfulness and the $CO_2$ emission during a production process. Geopolymer materials attract some attention as an inorganic binder due to their superior mechanical and eco-friendly properties. In this study, geopolymer-based cement was prepared by using aluminosilicate minerals (flyash, meta-kaolin) with alkaline-activators and its compressive strength with concentration of alkaline-activators was investigated. Aluminosilicate-based geopolymers were obtained by mixing aluminosilicate minerals, alkaline solution (NaOH or KOH with different concentration) and water-glass under the vigorous stirring for 20 min. Compressive strength after curing at $30^{\circ}C$ for 3 days increased with the concentration of alkaline-activator due to the enhanced polymerization of the aluminosilicate materials and dense microstructure. Aluminosilicate-based geopolymer cement using KOH as an alkaline-activator showed high compressive strength compared with NaOH activator. In addition, geopolymer cement using fly-ash as a raw material showed higher compressive strength than that of meta-kaolin.