• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.323-323
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• 2010

Saw damage of crystalline silicon wafer is unavoidable factor. Usually, alkali treatment for removing the damage has been carried out as the saw damage removal (SDR) process for priming the alkali texture. It usually takes lots of time and energy to remove the sawed damages for solar grade crystalline silicon wafers We implemented two different mixed acidic solution treatments to obtain the improved surface structure of silicon wafer without much sacrifice of the silicon wafer thickness. At the first step, the silicon wafer was dipped into the mixed acidic solution of $HF:HNO_3$=1:2 ration for polished surface and at the second step, it was dipped into the diluted mixed acidic solution of $HF:HNO_3:H_2O$=7:3:10 ratio for porous structure. This double treatment to the silicon wafer brought lower reflectance (25% to 6%) and longer carrier lifetime ($0.15\;{\mu}s$ to $0.39\;{\mu}s$) comparing to the bare poly-crystalline silicon wafer. With optimizing the concentration ratio and the dilution ratio, we can not only effectively substitute the time consuming process of SDR to some extent but also skip plasma enhanced chemical vapor deposition (PECVD) process. Moreover, to conduct alkali texture for pyramidal structure on silicon wafer surface, we can use only nitric acid rich solution of the mixed acidic solution treatment instead of implementing SDR.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.602-611
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• 2022

The persistence of pathogenic Escherichia coli under acidic conditions poses a serious risk to food safety, especially in acidic foods such as kimchi. To identify the bacterial factors required for acid resistance, transcriptomic analysis was conducted on an acid-resistant enterotoxigenic E. coli strain and the genes with significant changes in their expression under acidic pH were selected as putative resistance factors against acid stress. These genes included those associated with a glutamate-dependent acid resistance (GDAR) system and copper resistance. E. coli strains lacking GadA, GadB, or YbaST, the components of the GDAR system, exhibited significantly attenuated growth and survival under acidic stress conditions. Accordantly, the inhibition of the GDAR system by 3-mercaptopropionic acid and aminooxyacetic acid abolished bacterial adaptation and survival under acidic conditions, indicating the indispensable role of a GDAR system in acid resistance. Intriguingly, the lack of cueR encoding a transcriptional regulator for copper resistance genes markedly impaired bacterial resistance to acid stress as well as copper. Conversely, the absence of YbaST severely compromised bacterial resistance against copper, suggesting an interplay between acid and copper resistance. These results suggest that a GDAR system can be a promising target for developing control measures to prevent E. coli resistance to acid and copper treatments.

• Journal of Ginseng Research
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• 제17권2호
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• pp.145-147
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• 1993

The amounts of ginseng acidic polysaccharide (GAP) in red ginseng (Panax ginseng) were higher than those of wild and cultured Panax quinquefolius, Panax notoginseng as well as white ginseng (Panax ginseng). In white ginseng, there is no difference in the GAP amount among root ages or sizes. Also, the GAP amount of red ginseng body was similar to that of ginseng rhizome, but was higher than that of leaf and epidermis.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2594-2596
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• 2013

Highly chemo- and regioselective reaction of hydroxybenzenes with ${\alpha},{\beta}$-unsaturated compounds in acidic ionic liquid l-butyl-3-methylimidazolium hydrogen sulphate ([BMIM]HSO4) was reported for the first time. A series of oxa-Michael adducts and Friedel-Crafts alkylated products were synthesized with good yields. The acidic ionic liquid could be easily recycled for at least 5 times with only minor loss in activity.

• 자원리싸이클링
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• 제7권1호
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• pp.41-49
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• 1998

알루미늄계 응집제를 사용한 수처리시 발생하는 슬러지를 산으로 처리하여 응집제를 회수하는 방안과 그로 인한 잔류 슬러지의 부피 및 질량감소, 탈수성질의 변화, 그리고 산처리시의 영향요인 등에 관해 논의하였다. 회수된 응집제의 특성은 알루미늄의 함량, 응집 효율성, 잔류 불순물들에 의해 평가될 수 있다. 산처리후 발생하는 잔류 슬러지의 처리방법 및 실제 공정 운영에의 적용사례 등에 관해서도 논의하였다.

• 한국식품영양학회지
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• 제4권2호
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• pp.161-166
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• 1991

The blocked N-terminus and N-terminal sequence of soybean B-amylase were aetermined by analyzing the acidic peptides derived on peptic digestion of the enzyme. The acidic peptides were separated from the digest on a Dowex 50$\times$2 column(1X5cm) and purified by reversed phase-high performance liquid chromatography(RP-HPLC). The major acidic peptide, PEP-1, was a heptapeptlde. The N-terminal 7 amino acid sequence of soybean B-amylase was deduced to be acetyl-Ala-Thf-Ser-Asp-Ser-Asn-Met- from the results of sequence analysis of PEP-1 and amino acid analysis of other acidic peptides.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.335-343
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• 2011

We examined the effect of the acidic liquid from carbonized rice hull(ALCRH) treatments to molded fiber packages(MFP) on weight, Haugh unit, pH and microbial activity of egg to extend the shelf life in egg packaging. Higher concentration and surface spray treatment of the acidic liquid extended the shelf life of egg. ALCRH treatment to MFP improved the performance of the packaging for egg in terms of decreased weight loss and retarded microorganism growth of eggs during storage.

• 한국식품영양학회지
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• 제8권2호
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• pp.110-115
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• 1995

This study was devised to observe the inhibitory effects of ethanol treatment precipitate (crude acidic polysaccharide) from Korean red ginseng on a lipolytic action of Toxohormone-L which has been known as lipolytic and anorexigenic factors. Toxohormone-L was obtained by partial purification of the ascites fluid from mice which had been inoculated with sarcoma-180. The yields of crude acidic polysaccharide from Korean red ginseng was 63.5%. In vitro, at the concentration of 500rg /ml, the inhibition rate of lipolysis by the crude acidic polysaccharide of Korean red ginseng was 38.8% and the total inhibitory activity per gram of ginseng material was 4,928 nit. In vivo, the red ginseng polysaccharide(40mg/ml in saline soon.) 16ul/g of body weight was injected to the sarcoma-180 bearing mice once In 3 days until death. The effects against the extension of life span was little but body weight gain of sarcoma-180 bearing mice decreased significantly by administration of Korean red ginseng polysaccharide compared to those of the control group.

• Journal of Ginseng Research
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• 제14권1호
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• pp.10-13
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• 1990

Effect of an acidic polysaccharide fraction In Korean white and red ginseng on lipolytic action of Toxohormone-L was studied. Crude acidic polysaccharide fraction was extracted from main and lateral root of Korean white and red ginseng separately and purified several times. Inhibitory effect of crude polysaccharide fraction was determined by unit (1 unit is loft inhibition rate per Is sample). Yields of purified crude polysaccharide fraction of main and lateral root of red ginseng were 2.9 and 2.2 times higher than those of white ginseng, respectively. Inhibitory effects of main root of white and red ginseng, 11.hen final reaction concentrations of sample were 50, 100, 200, 500 $\mu$g/ml, were 37.2가 and 23.7% higher than those of lateral root of white and red ginseng. Inhibitory effect of main root of red ginseng was 2.3 times higher than that of white ginseng.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2140-2144
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• 2012

A polymer support immobilized acidic ionic liquid was prepared by copolymerization of 3-vinyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate with styrene in the presence of benzoyl peroxide and its primary application as a solid acidic heterogeneous catalyst to the synthesis of Hantzsch 1,4-dihydropyridines through a one-pot three-component reaction of aromatic aldehydes, ethyl acetoacetate and ammonium acetate was investigated. The results showed that this heterogeneous catalyst has high catalytic activity and the desired products were obtained in good to high yields. Moreover, the catalyst was found to be reusable and a considerable catalytic activity still could be achieved after third run.