• 펄프종이기술
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• 제31권2호
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• pp.50-57
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• 1999

This study was carried out to compare a conventional alkaline flotation deinking conditions with neutral deinking conditions with and without enzyme addition with respect to the ink removal efficiency and theflotation deinking filtrate quality such as chemical oxygen demand, cationic demand, suspended solids. Based on ink removal rate the neutral deinking condition without enzyme was better than the alkaline deinking condition, and the neutral deinking with enzyme addition turned out to be the best. The brightness of the deinked pulp was found to be the same trend as the ink removal rate. Flotation reject rate for the neutral deinking condition without enzyme was higher than that of the alkaline deinking condition, but that of the neutral deinking condition with enzyme was lower than that of the alkaline and the neutral deinking condition without enzyme. On the freeness of the deinked pulp, the neutral deinking condition with enzyme had the highest value and the alkaline deinking condition had the lowest value among the conditions tested. On the filtrate of the flotation stage, the cationic polymer demand of the neutral deinking condition with enzyme was much lower than the other conditions. Suspended solids and chemical exygen demand for the neutral flotation deinking filtrate was lower than those of the alkaline flotation deinking filtrate.

• 환경위생공학
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• 제23권1호
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• pp.25-31
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• 2008

A bacterial strain, Bacillus megaterium L-49 has been isolated and identified that produces alkaline ${\alpha}$-amylase. The cell is ellipsoidal, about $1.0-1.2{\times}3.0-3.6{\mu}m$ in diameter, Gram-positive, motile, and central partial central. Growth occurs in media containing 7% of NaCl. This strain could utilize D-glucose, lactose, xylose, sucrose, mannose, and maltose, and but it does not utilize D-fructose, and glycogen. Among the various concentrations of saturated ammonium sulfate, the retractation ratio in range of 70 to 100% was about 93%. However, in the case of acetone, it was about 98.7%. EDTA has activating effect and Ca2+ has no effect on alkaline ${\alpha}$-amylase activity. The alkaline ${\alpha}$-amylase has low thermal stability. The optimal temperature for reaction is $50^{\circ}C$. The alkaline ${\alpha}$-amylase activity maintained stabilizing at pH 6-11 and the optimal pH for reaction was 9-10.

• 한국동물위생학회지
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• 제41권2호
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• pp.125-131
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• 2018

This study investigated the effects of the alkaline detergent and acid rinse used for cleaning milking machines on the rubber composition of the newly-developed teat cup liners. The samples prepared for use in the clean-in-place process were analyzed by ultraviolet spectrophotometer, ion chromatography and liquid chromatography. In the absorption spectrum of the first sample solution, the form of absorbance or absorption peak was largely different, compared to the absorption spectrum of alkaline detergent alone, but in the absorption spectra of the second and third sample solutions, the absorbance decreased, which was similar to the absorption spectrum in the pure acid detergent. In the ion chromatogram, two main peaks only, which might be shown by the pure alkaline detergent alone, were measured. In the liquid chromatograms, however, new peaks were observed in addition to the two main peaks caused by the pure alkaline detergent alone, which suggested that various molecular materials were created or eluted from the liner by the reaction with the alkaline detergent, but when washed with the acid detergent, any ion species were not produced. Therefore, we propose that an acid rinse should be applied, after cleaning the milking machine with the alkaline detergent.

• 한국동물학회지
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• 제16권2호
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• pp.139-145
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• 1973

솔나방(Dendrolimus spectabilis)의 變態에 따른 acid 및 alkaline phosphatase의 活性度의 變化를 測定하였다. 두 酵素의 活性度는 幼蟲의 成長과 더불어 增加하고 전용기에서 減少하였다. Acid phosphatase는 용기의 初에, 그리고 alkaline phosphatase는 幼蟲8齡에서 각각 最高의 活性을 나타내었다. 전용기에서 두 酵素간의 活性度의 차이는 크게 나타나지 않았으나 幼蟲8齡에서 보다는 훨씬 낮았다. Acid phosphatase의 活性度는 용기초에 增加하고 용기말에서 減少하다가 成蟲에서 다시 上昇하였다. Total phosphatase의 活性度의 變化는 變態에 따른 生理的曲線인 U字型 pattern을 나타내었다.

• 대한화학회지
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• 제61권6호
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• pp.311-319
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• 2017

By using Density Functional Theory (DFT), we have performed alkali metal and alkaline earth metal inside fullerene-like BeO cluster (FLBeOC) in terms of energetic, geometric, charge transfer, work function and electronic properties. It has been found that encapsulated processes of the alkali metal are exothermic and thermodynamically more favorable than alkaline earth metal encapsulation, so that interaction energy ($E_{int}$) of the alkali metal encapsulation FLBeOC is in the range of -0.02 to -1.15 eV at level of theory. It is found that, the electronic properties of the pristine fullerene-like BeO cluster are much more sensitive to the alkali metal encapsulation in comparison to alkaline earth metal encapsulation. The alkali and alkaline earth metal encapsulated fullerene-like BeO cluster systems exhibit good sensitivity, promising electronic properties which may be useful for a wide variety of next-generation nano-sensor device components. The encapsulation of alkali and alkali earth metal may increase the electron emission current from the FLBeOC surface by reducing of the work function.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.872-876
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• 2001

Topological changes caused by the alkaline and enzymatic attacks of solution-grown, chain-folded lamellar crystals (SGCs) of poly[(R)-3-hydroxybutyrate] P(3HB) have been studied in order to investigate the chain-folding structure in P(3HB) crystal regions. NaOH and an extracellular PHB depolymerase purified from Alcaligenes faecalis T1 were used for alkaline and enzymatic hydrolysis, respectively. The measurements were performed on crystals attached to a substrate which is inactive to degradation mediums. Both alkaline and enzymatic attacks lead to a breakup of the lamellar crystals along the crystallographic b-axis during initial erosion. Since hydrolysis preferentially occurs in amorphous regions, this morphological result reflects relatively loosely packed chains in core parts of lamellar crystals. Additionally, it was supported by the ridge formation along the b-axis in the lamellar crystals after thermal treatment at a low temperature because of the thermally sensitive nature of the loosely packed chains in lamellar crystals. However, the alkaline hydrolysis accompanied the chain erosions or scissions in quasi-regular folded lamellar surfaces due to smaller size of alkaline ions in comparison to the enzyme, resulting in the decrease of molecular weight.

• 전자공학회논문지
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• 제53권8호
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• pp.129-135
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• 2016

본 연구는 알칼리 환원수기에 3가지 필터(활성카본, 중공사막, 카본블럭)를 이용해서 원수를 통과시켜 통수 양에 따른 산화환원전위(Oxidation Reduction Potential) ORP값이 안정화되는 것을 평가한 것이다. 알칼리 환원수기는 환원의 기능을 가지고 있는 물을 만드는 시스템으로 인체에 유익한 미네랄과 ORP값이 일반 물에 비해 매우 낮은 값을 가지고 있는 기능수이다. 필터를 통과한 물을 전기 분해하면 물속에 있는 음이온과 양이온은 격막을 통해서 -전극 쪽에는 칼슘($Ca^+$), 칼륨($K^+$), 마그네슘($Mg^+$), 나트륨($Na^+$)을 포함한 물로 인체에 유익한 미네랄이 포함된 알칼리 환원수를 얻고 +극에는 염소(Cl),인(P),유황(S)등 - 이온을 띄고 있는 유기물이 만들어 진다. 실험에서 알칼리 환원수(Alkaline Reduced Water)에서 전기분해의 전압의 크기를 조절하여 1단(pH8), 2단(pH8.5), 3단(pH9), 4단(pH9.5)으로 알칼리 환원수에 사용되고 -1단(pH6.0), -2단(pH5.0)의 산성산화수로 사용하고 있다. 이러한 시스템으로 3가지 필터에 통수하면서 ORP값이 어떻게 변화하고 어느 정도에서 안정화되는지를 평가하였고 대략 100L는 통수되어야 ORP값이 안정화하는 것을 측정하고 평가하였다.

• 한국미생물·생명공학회지
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• 제8권2호
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• pp.77-85
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• 1980

Protease의 생산능이 우수한 Asp. oryzae KC-15를 선정하고 다음과 같은 결과를 얻었다. 1. Wheat bran medium에서의 최적배양시간은 acid protease와 neutral protease는 약 48시간, alkaline protease는 약 72시간이었고 본 균주가 생산하는 protease는 alkaline protease와 neutral pro-tease가 주체이며 acid protease는 극히 미약하였다. 2. Wheat bran medium 에 $Na_2$HPO$_4$, NaH$_2$PO$_4$, Glucose, rice powder 및 Na-glutamate의 첨가는 alkaline protease와 neutral psotease의 생산에, (NH$_4$)$_2$HPO$_4$, glucose 및 rice powder의 첨가는 acid protease의 생산에 효과적이었다. 3. 조효소의 특징(equation omitted) 4. 내열제로서 NaH$_2$PO$_4$가장 효과적이었으며 최적첨가량은 alkaline protease와 neutral protease 에 대하여는 10mg, acid protease에 대하여는 5mg 이었다. 5. 6$0^{\circ}C$ 이상에서는 NaH$_2$PO$_4$의 내열효과는 거의 인정할 수 없었다. 6. NaH$_2$PO$_4$10mg을 첨가하고 55$^{\circ}C$에서 30분간 처리하였을 때의 잔존활성은 alkaline protease는 약 58%, neutral protease는 약 57%, acid protease는 약 55 %이었다.

• 한국동물학회지
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• 제23권2호
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• pp.61-68
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• 1980

발정주기에 EK라서 생쥐자궁의 alkaline phosphatase와 transport ATPases의 활성변화를 알아보기 위하여 정량적으로 분석하였다. 발정주기의 각 시기에 있어서 이 효소활성들의 비율은 대체로 그 양상이 서로 비슷하나, 발정기의 $K^+$-dependent와 $Na^+, K^+$-activated ATPases를 제외한 다른 효소들의 활성은 다른 어떤 시기보다도 유의하게 (p<0.025) 높았다. 즉, $K^+$-dependent와 $Na^+, K^+$-activated ATPases의 활성은 발정간기에서 발정기에 이르는 동안 무시할 정도이고, 다만 발정후기에 약간의 활성(0.04$\\sim$0.05 $\\mu$M/mg protein/hr), 총활성의 6$\\sim$7%)이 나타났다. 한편, 발정기에서 $Mg^++$-dependent phosphatase, transport ATPase와 alkaline phosphatase의 활성들은 급속히 현저하게 증가하였으며 각각 0.69(35%), 0.42(21%), 1.58(79%)였다. Alkaline phosphatase는 전 발정주기를 통해 0.60$\\sim$1.58(79$\\sim$90%)의 활성을 보여 그 주종을 이루었다. Alkaline phosphatase의 활성중에는 $Mg^++$-dependent의 것이 총활성의 12$\\sim$16%로 추정되었다. 그러므로 $K^+$-dependent와 $Na^+$-activated ATPases는 발정기 때에 자궁액의 누적을 조절하는 요인이 아니고 발정후기에는 자궁상피 속으로 내액을 재흡수하는 요인인 것으로 짐작되며, EH한 $Mg^++$-dependent phosphatase, transport ATPase 그리고 alkaline phosphatase는 생쥐의 자궁 상피세포에서부터 내액을 분지하는 데에 밀접히 관련되어 있는 것으로 사려된다.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.662-671
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• 2015

To enrich the genetic resource of microbial xylanases with high activity and stability under alkaline conditions, a xylanase gene (xynSL4) was cloned from Planococcus sp. SL4, an alkaline xylanase-producing strain isolated from the sediment of soda lake Dabusu. Deduced XynSL4 consists of a putative signal peptide of 29 residues and a catalytic domain (30-380 residues) of glycosyl hydrolase family 10, and shares the highest identity of 77% with a hypothetical protein from Planomicrobium glaciei CHR43. Phylogenetic analysis indicated that deduced XynSL4 is closely related with thermophilic and alkaline xylanases from Geobacillus and Bacillus species. The gene xynSL4 was expressed heterologously in Escherichia coli and the recombinant enzyme showed some superior properties. Purified recombinant XynSL4 (rXynSL4) was highly active and stable over the neutral and alkaline pH range from 6 to 11, with maximum activity at pH 7 and more than 60% activity at pH 11. It had an apparent temperature optimum of 70℃ and retained stable at this temperature in the presence of substrate. rXynSL4 was highly halotolerant, retaining more than 55% activity with 0.25-3.0 M NaCl and was stable at the concentration of NaCl up to 4M. The enzyme activity was significantly enhanced by β-mercaptoethanol and Ca²⁺ but strongly inhibited by heavy-metal ions and SDS. This thermophilic and alkaline- and salt-tolerant enzyme has great potential for basic research and industrial applications.