• 한국연초학회지
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• 제13권1호
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• pp.5-12
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• 1991

(A series of cigarettes made from) RTL containing different leveles of added sugars (2.0. 5.0 and 8.0%) and acids(0.4, 0.8 and 1.2%) have been examined. Compared to the control cigarette there was reduced in the delivery of tar and nicotine in smoke on 5.0% addition of glucose there was a signification reduced the delivery of nicotine the addition of glucose or fructose decreased the delivery of nicotine tar and co. However, tar in smoke was an increased in the delivery of tar and nicotine was observed, when sucrose and lactose were the added sugars. The smoking taste by the addition of glucose and fructose on R.T.L. was found to be milder than by the others sugars. Tar and nicotine deliveries showed a decreasing trend with the addition of organic acid and tartaric acid among the organic acid described above had greater effect than the others acids 1.2% addition of tartaric acid gave some 11-31% reduction in tar and nicotine delivery and a fall of smoke pH from 4.49 was found. Smoking taste by the addition of lactic acid and tartaric acid had milder than the others and heat treatment for 10 minutes at 13$0^{\circ}C$ gave also better on smoking: taste. The addition of mixture of sugars and organic acid (glucose 5% + lactic acid 0.6% + tartaric acid 0.6%) and then the successive heat treatment for 10 minutes at 13$0^{\circ}C$ improved greatly the Quality of R.T.L. and nicotine were reduced to 11-28% and pH was changed from 5.40 to 3.89.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.394-394
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• 2010

Ammonium ion (${NH_4}^+$) was suggested as the origin of interstellar $6.85\;{\mu}m$ band. Early study, in which organic molecule and water ice film mixtures were photolyzed so that organic acids could be produced, explained the generation of ${NH_4}^+$ from the reaction of photogenerated organic acid and ammonia ($NH_3$). However, the observed abundance of organic acids or their counter-anions are not so high in interstellar ice and not enough to protonate $NH_3$ into ${NH_4}^+$ in the observed level. Because of the shortage in photogenerated organic acids, the candidate of acid which protonates $NH_3$ should be modified. Here, we prepare $NH_3/H_2O$ binary mixtures and photolyze them with vacuum ultraviolet (VUV, peak at 10.6 and 10.0 eV). We find the ammonium ion (${NH_4}^+$) from photolyzed mixture by using low energy sputtering (LES) and reflection absorption IR spectroscopy (RAIRS). As a hydronium ($H_3O^+$) can be produced by UV irradiation and protonate bases, ${NH_4}^+$ may be formed from the reaction of photogenerated $H_3O^+$ and $NH_3$. We show the generation of ${NH_4}^+$ without any kind of organic molecules or acids, and it may explain the relatively high abundance of ${NH_4}^+$ compared to the counter-anions or organic acids in interstellar ice.

• 멤브레인
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• 제30권6호
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• pp.420-432
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• 2020

(PIM-1)과 ellagic acid로 만든 랜덤형 공중합체가 간단한 방법으로 합성되었으며, 이산화탄소 분리막에 대한 적용 가능성에 대해서 연구하였다. 이 공중합체의 경우 PIM (polymers with intrinsic microporosity) 고분자의 미세 기공 구조에 기인한 높은 기체 투과도와 평면 구조와 친수성을 갖는 ellagic acid에 기인한 높은 이산화탄소에 대한 선택성에 의해 우수한 이산화탄소 기체 분리 성능을 나타내었다. 즉, 이산화탄소에 대한 투과도 4516 Barrer와 CO2/N2 (> 23~26) 및 CO2/CH4 (>18~19)의 높은 선택성으로 두 쌍의 가스 혼합물에 대해 Robeson 상한(2008)을 초과한 결과를 나타내었다. 이와 같이 PIM-1에 평면구조를 갖는 ellagic acid을 혼입하면 PIM-1의 꼬인 구조를 방해하여 기체 투과성을 향상 시킬 뿐만 아니라 공중합체의 강성과 극성이 증가하여 N2 및 CH4에 대한 CO2의 선택성을 증가시키는 결과를 확인하였다.

• 한국식품과학회지
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• 제33권2호
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• pp.256-263
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• 2001

전통 고추장의 품질개선과 균일화를 위하여 메주 종류를 달리하여 고추장을 제조하고 발효시키면서 이화학적 성분의 변화를 관찰하였다. 고추장의 품질지표인 아미노산성 질소는 P-2 고오지 단독 첨가구(KP2), P-1 고오지 단독 첨가구(KP1), 전통메주와 P-2 고오지 혼합 첨가구(MKP2)의 함량이 높아 고오지 첨가로 고추장 품질 개선의 가능성이 제시되었다. 고추장 발효 중 산도와 pH는 메주 종류에 따른 뚜렷한 차이는 없었다. 고추장의 신맛의 척도가 되는 유기산은 모든 시료에서 citric acid의 함량이 가장 높았고 그 다음으로 malic acid, oxalic acid, succinic acid, acetic acid, lactic acid 순이었다. 총 유기산 함량은 담금 초 보다 후기에 높았고 메주 종류에 따른 유의적 차이는 없었으나 발효 100일 후 P-2 고오지 첨가구의 함량이 높았다. 고추장 발효 중 검출된 유리당은 maltose, fructose, glucose로 P-1 고오지를 일부 또는 전체 첨가한 시료(MKP1, KP1)에서 그 함량이 높아 고추장의 단맛을 증가 시키는데 고오지 첨가가 유리할 것으로 확인되었다. 고추장의 주요 유리아미노산은 aspartic acid, glutamic acid, alanine, phenylalanine, argine 등이었고 총 유리아미노산 함량은 아미노산성 질소의 함량변화와 유사한 경향으로 고오지 함량이 많을수록 높았다. 숙성이 완료된 고추장의 관능평가 결과 색택, 냄새, 맛, 전체적 기호도에서 처리구간의 유의적 차이는 없었으나 전통메주와 P-1 고오지 혼합첨가구(MKP1)와 전통 메주와 P-2 고오지 혼합첨가구(MKP2)에서 종합적 기호도가 높았다.

• Applied Biological Chemistry
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• 제25권4호
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• pp.206-210
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• 1982

pH, 유기산(有機酸), ascorbic acid 및 자외선조사(紫外線照射)가 홍삼갈색화반응촉진(紅蔘褐色化反應促進)에 미치는 영향(影響)을 조사(調査)하였다. 홍삼(紅蔘)의 갈색화반응(褐色化反應)은 약(弱) alkali성(性) 범위(範圍)에서 갈변(褐變)이 촉진(促進)되는 경향(傾向)을 보였으며 citric acid, succinic acid, tartaric acid등(等)의 유기산(有機酸) 첨가(添加)도 홍삼(紅蔘)의 갈변반응(褐變反應)을 촉진(促進)하였다. Fumalic acid의 단독첨가(單獨添加)는 홍삼(紅蔘)의 갈색화반응(褐色化反應)을 촉진(促進)하였으나 glucose, glutamic acid , $glucose{\times}glutamic$ acid의 혼합처리(混合處理)는 갈변(褐變)을 저하(低下)시켰다. 0.1M 이상(以上)의 ascorbic acid 처리(處理)는 홍삼갈색화반응(紅蔘褐色化反應)에 아주 큰 촉진효과(促進效果)가 있었으며 동시(同時)에 양질홍삼(良質紅蔘)의 특유(特有)한 색상(色相)인 홍색도(紅色度)도 크게 증대(增大)되었다. 자외선조사(紫外線照射)는 홍삼건조(紅蔘乾燥) 초기(初期)에는 갈변(褐變)을 상당히 촉진(促進)하였으나 그 이후(以後)에는 갈색도(褐色度)가 감소(減少)되었다.

• 한국연초학회지
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• 제6권1호
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• pp.84-93
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• 1984

Six kinds of sugars (Maltose, Sucrose, Glucose, Fructose, Mannose and Lactose) and four kinds of organic acids (Malic, Tartaric, Lactic and Citric) were added by 2-10% for the former and 0.2-1.8% for the later in quantitatively to the inferior quality of Flue-cured leaf tobaccos, and treated at 135$^{\circ}C$ for 10 minutes to examine the effect on deliveries of tar and nicotine in smoke, variation of smoke pH and smoking taste. The results obtained are as follows. Tar and nicotine deliveries in smoke of tobacco show a great reduction with 5-6% addition of sugars. Reduction of nicotine delivery was to be 19% with addition of Glucose. Tar in smoke was, however, increased by 5-8% with 4% addition of Sucrose or Lactose. On the other hand, 4% addition of Glucose and Fructose gave 1 % reduction of tar delivery, but the reduction rate became to be small with increase of adding quantity. The smoking taste by the addition of Glucose and Fructose tobacco was found to be milder than by the other sugars. Tar and nicotine deliveries show a decreasing trend with the addition of organic acid, and Tartaric acid, among the organic acids described above, had greater effect than the other acids. 1% addition of Tartaric acid gaves 10-11% reduction in tar and nicotine delivery, and a fall of smoke pH, from 6.40 to 6.05, was found. Smoking taste by the addition of Lactic and Tartaric acid had milder than the others. And heat treatment for 10 minutes at $135^{\circ}C$ gave also better on smoking taste. The addition of mixture of sugars and organic acids, (Glucose 4%+Lactic acid 0.8% + Tartaric acid 0.2%) and then the successive heat treatment for 10 minutes at $135^{\circ}C$ improved greatly the quality of Fluecured leaf tobacco, and nicotine were reduced to 16-29%, and pH was changed from 6.46 to 6.14.

• 한국물환경학회지
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• 제25권3호
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• pp.419-424
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• 2009

Characteristics of humic substances on the changes in dissolved organic matter (DOM) characteristics by biodegradation was investigated using three types of the artificial water samples composed of glucose and Suwannee River fulvic acid (SRFA). Some selected DOM characteristics including the specific UV absorbance (SUVA), the synchronous fluorescence spectra and the molecular weight (MW) were compared for the artificial water samples before and after 28-day microbial incubation. The changes of the DOM characteristics were minimal for SRFA during the incubation whereas they were significant for glucose. SUVA, dissolved organic carbon (DOC)-normalized fluorescence intensity, and MW values of glucose increased, suggesting that such labile organic compounds could be exclusively transformed into more humidified materials by biodegradation. For glucose-SRFA mixture, the selected DOM characteristics were greater than those estimated using the assumption that the individual changes of either glucose or SRFA are conservative for the mixture of the two materials. Our results suggest that the presence of humic substances (HS) may lead to the enhancement of the formation of refractory organic materials during biodegradation of labile compounds. Detailed analyses of size exclusion chromatography (SEC) revealed that the enhancement occurred for the DOM mixture with a MW range between 500 Da to 4000 Da.

• 한국유기농업학회지
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• 제25권1호
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• pp.171-185
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• 2017

GABA는 glutamic acid decarboxylase에 의해서 L-glutamic acid가 탈탄산화되어 생합성된 비단백질 아미노산이다. GABA는 식물에서 스트레스에 대항한 대응반응으로 생성된다. 사람의 중추신경계에서는 주요 억제성 신경전달물질 중 하나로 항고혈압, 항당뇨 효능이 있다고 알려져 있다. 본 연구에서 우리는 보리 잎과 옥수수 수염을 유산균과 함께 발효함으로써 GABA 생성을 증진시키고자 하였다. 보리 잎과 옥수수 수염을 다양한 무게 비율로 조합하여 혼합하였고, $30^{\circ}C$에서 48시간 동안 배양기 안에서 L. plantarium과 함께 발효시켰다. 발효된 혼합물을 열수 추출한 후, thin layer chromatography와 GABase assay를 이용하여 GABA의 생산을 분석하였다. 우리는 9:1 혼합발효추출물이 다른 비율의 추출물 보다 GABA 함량이 높은 것을 확인하였는데 이것은 혼합과 발효기술이 보리 잎과 옥수수 수염 내 GABA 양 증진에 효과가 있음을 의미한다. 또한 몇 가지 생리활성을 분석한 결과 혼합발효추출물의 항산화 효능이 비발효 추출물에 비하여 증진되었고 세포독성은 나타나지 않음을 확인하였다. 이러한 결과는 보리 잎과 옥수수 수염의 조합과 이것을 유산균과 함께 발효시키는 방법이 고함량의 GABA와 증진된 생리 활성을 지닌 기능성 식품으로서의 개발 가능성이 있음을 의미한다.

• 치위생과학회지
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• 제19권1호
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• pp.1-8
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• 2019

Background: Erosion is a gradual process that occurs fairly quickly, and the full extent of the erosive effects of acidic beverages is not yet clear. The present study aimed to determine the differences in the erosive potentials among four naturally acidic fruit nectars within the same range of titratable acidity and to determine the influence of the components of organic acids on tooth erosion. Methods: Diluted fruit nectars (mandarin 1:1.1, orange 1:1.7, lemon 1:15, grapefruit 1:20) with the same range of titratable acidity (7.9 ml) and their corresponding organic acids (0.05%, 0.1%, 0.3%, and 0.5% citric acid, malic acid, and a citric and malic acid mixture [pH 2.8], respectively) were used. Specimens were placed in conical tubes with 50 ml of each of the test solutions for 1 hour. A microhardness test and scanning electron microscopy were used to measure enamel erosion. Acid separation was carried out using high-performance liquid chromatography to analyze the composition of each test solution. Results: Similar decreases in the Vickers hardness number (VHN) were observed among the groups treated with the following diluted fruit nectars: diluted mandarin nectar ($75.9{\Delta}VHN$), diluted lemon nectar ($89.1{\Delta}VHN$), diluted grapefruit nectar ($91.7{\Delta}VHN$), and diluted orange nectar ($92.5{\Delta}VHN$). No statistically significant differences were found in the enamel surface hardness after erosion (p>0.05). Citric and malic acids were the major organic acids in the test fruits. The lemon and orange groups had the highest malic acid concentrations, and the mandarin group had the lowest malic acid concentration. Conclusion: The titratable acidity and the citric and malic acid contents of the fruits could be crucial factors responsible for enamel erosion. Therefore, fruit-based drinks should be regarded as potentially erosive.

• Mass Spectrometry Letters
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• 제8권2호
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• pp.29-33
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• 2017

Understanding the mechanisms that control and concentrate the observed electrospray ionisation (ESI) response from peptides is important. Controlling these mechanisms can improve signal-to-noise ratio in the mass spectrum, and enhances the generation of intact ions, and thus, improves the detection of peptides when analysing mixtures. The effects of different mixtures of aqueous: organic solvents (25, 50, 75%; v/v): formic acid solution (at pH 3.26) compositions on the ESI response and charge-state distribution (CSD) during mass spectrometry (MS) were determined in a group of biologically active peptides (molecular wt range 1.3 - 3.3 kDa). The ESI response is dependent on type of organic solvent in the mobile phase mixture and therefore, solvent choice affects optimal ion intensities. As expected, intact peptide ions gave a more intense ESI signal in polar protic solvent mixtures than in the low polarity solvent. However, for four out of the five analysed peptides, neither the ESI response nor the CSD were affected by the volatility of the solvent mixture. Therefore, in solvent mixtures, as the composition changes during the evaporation processes, the $pK_b$ of the amino acid composition is a better predictor of multiple charging of the peptides.