• 대한화학회지
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• 제28권1호
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• pp.14-19
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• 1984

메트미오글로빈의 압력에 의한 변성의 $H_2O$와 $D_2O$에서의 차이를 pH 5.7과 pH 7.0에서 연구하였다. 메트미오글로빈은 $D_2O$에서 $H_2O$보다 더 작은 압력에서 변성하였다. 그 차이가 pH 5.7에서가 pH 7에서 보다 더 컸다. $H_2O$와 $D_2O$에서 이 안정도의 차이가 단백질에 대한 $H^+$와 $D^+$의 결합에 차이가 있기 때문이며 또한, 수소가 중수소로 바뀜에 따르는 구조 변화 때문인 것으로 사료된다.

• Journal of Oral Medicine and Pain
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• 제8권1호
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• pp.127-142
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• 1983

This thesis was to investigate sex defferencd by employing the methodes of Bernadskij's and it's modification by means of the evaluation of pH of dentin in 162 extracted teeth. The obtained were as follows: 1. In 72% of all experinments, pH of human dentin substance was higher in female than in male. Mean pH was 13.175±0.031 in male and 13.245±0.030 in female. 2. After comparative studies on each pH in anatomical region of tooth arrangement, the sex difference of pH was most obviously showed in molars. 3. In pH change according to ages, the 30's was the highest in male and the 20's in female, also pH showed decresing tendency by the increasing of age in both male and female. 4. There was no pH difference in anatomical regions of tooth arrangment. 5. Mean pH was 13.282±0.013 in under 50 years of age and 13.282±0.022 over 50. It proved that pH was higher in under 50 years of age than in over 50.

• 한국미생물·생명공학회지
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• 제23권1호
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• pp.31-35
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• 1995

Using the alkalophillic Bacillus sp. SH-8 and its mutant Bacillus sp. SH-8M capable of growing at the neutral pH, the amino acid compositions of the cell wall and cell membrane were studied at varying cultivation pH's. The pattem of protein electrophoresis was also tested. It was elucidated that the amino acids consisting of the cell wall were alanine, glutamic acid, lysine, aspartic acid, and meso-diaminopimelic acid. There was not any significant difference in the amino acid compositqon betweeo`two straqns regardless of the culture pH. As the results of HPLC ssay, glutamic acid and aspartic aciu accounted for more than 50% in the amqno acid composytqon of the cell wall. By the isolatqon of the crude cell membrane and the SDS-PAGE analysis, it was found that there was a considerable difference qn the protein pattern when the straqns were cultured at the neutral pH. In addition, by the two dimensional gel electrophoresis, it was confirmed that there was a difference in the protein patterns between two strains cultivated at the neutral pH medium but no difference at the alkaline medium.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.571-574
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• 2000

Hydrolase는 생물학적 공정에서 가장 널리 사용되는 효소군 중의 하나이다. 본 연구에서는 hydrolase들 중에 xylanase, lysozyme, glucoamylase, barnase가 대상 hydrolase로 선택하여 최적 pH를 예측하는 방법론을 제시하였다. Tanford-Kirkwood(TK) model에 기반을 두고 선택된 효소들의 catalytic residue들의 전하 변화가 optimum pH에 중요한 인자로서 그 catalytic residue들의 전하 차이가 최대일 때의 pH가 optimum pH로 나타났다. 이렇게 예측된 optimum pH 결과들은 실험적으로 결정된 optimum pH와 서로 잘 일치하고 있음을 보여준다.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.417-420
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• 2011

In this experiment, we examined the survival, fertilization, hatching times, and hatching rates of Far Eastern catfish Silurus asotus at pH ranging from 2 to 13 under laboratory conditions. Eggs could be fertilized at pH 3-12. In a hatching experiment, mortality was first observed at pH 13, when all fertilized eggs died within 8 min, followed by pH 2 (30 min), pH 12 (60 min), pH 3 (4 h), and pH 11 (5 h). Hatching only occurred at pH 4-10, with the highest hatching rate at pH 7 (52%) and the lowest at pH 10 (24%). Hatching rates in acid solutions were higher than in alkaline solutions, although the difference was not significant. Hatching was first observed at pH 10, beginning 27 h after fertilization and ending at the 31 h. A clear difference was observed between hatching times, ranging from 31 to 64 h and increasing in order with descending pH.

• 대한정형도수물리치료학회지
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• 제24권1호
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• pp.67-75
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• 2018

Background: The purpose of this study was to investigate the effect of pressure distribution on the both foots with gluteus medius muscle intensive strengthening exercise in 4week. Methods: The purpose of this study was to investigate the effect of gluteus medius muscles strengthening exercise on the pressure distribution of the foot in 20 healthy adults. Four gluteus medius muscles strengthening exercise programs were conducted three times a week for four weeks. The pressure distribution changed of the right and left foot parts of the experimental group and the control group were measured and analyzed. Results: There was a significant difference in F1, F2, M1, M2, and H1 among the pressure distribution of the right foot of the experimental group (p<.05). There was a significant difference in F1, M1, M2, H1 and H2 among the pressure distributions of the left foot of the experimental group (p<.05). There was a significant difference in H1 among the pressure distribution of the right foot of the control group (p<.05). There was no significant difference in the pressure distribution of the left foot region of the control group (p>.05). There was a significant difference in H1 among the pressure distribution of the right foot between the group (p<.05). There was a significant difference in M2, H1 among the pressure distribution of the left foot between the group (p<.05). Conclusions: In the healthy adults, it was confirmed that the application of the gluteus medius muscles strengthening exercise had an effect on the weight shift during the walking due to the overall foot balance and the pressure distribution change of the foot part.

• 치위생과학회지
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• 제12권6호
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• pp.696-701
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• 2012

The purpose of this study was to determine pH value of some alcoholic drinks sold in Korea and to provide the basic information which can cause dental erosion. Alcoholic drinks commercially sold were purchased from various big markets in Korea. The sorts of drinks tested in this study consisted of 5 brands of beers, 24 brands of makgeollis, 9 brands of wines and 12 brands of sojus. The test groups were selected randomly and the pH of each beverage was determined using a pH meter he each pH was measured. For statistical data, Mann-Whitney test was used to analyze difference for red wine and white wine and Kruskal-Wallis test was used to compare the pH of each test group. The result of this study was as followings: the mean pH of 5 brands of beers was 4.21, that of 24 brands of makgeollis 3.88, of 9 brands of wines 3.34 and of 12 brans of sojus 7.86. Each test group was significantly different (p<0.05). Except for soju groups, the test groups had a low pH value which can cause dental erosion. In terms of comparing between pH value of red wine and white wine, the result of this study represented that the mean pH of red wine was 3.45 and that of white wine was 3.21. This result showed the pH of two kinds of wine had a low pH which can lead to dental erosion and the difference of two wine were significantly different (p<0.05). As a result, some drinks sold in Korea have a high erosive potential on teeth since they have a comparatively low pH expect soju. Hence, when we consume some kinds of alcoholic drinks, we make sure to remember that the alcoholics which had a low pH, can have an effect on dental erosion that mean we should avoid to drink some alcoholic drinks with low pH for long time.

• 센서학회지
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• 제21권3호
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• pp.186-191
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• 2012

In this paper, we present a pH measurement method that uses a microcantilever-array-based biosensor system. It is composed of microcantilever array, liquid cell, micro syringe pump, laser diode array, position sensitive detector, data acquisition device, and data processing software. Four microcantilevers are functionalized with pH-sensitive MHA(mercaptohexadecanoic acid) as a probe, while three microcantilevers are functionalized with HDT(hexadecane thiol) as reference. We prepare PBS(phosphate buffered saline) solutions of different pH and inject them into the liquid cell with a predefined volumetric speed at regular time intervals. The functionalized mircocantilevers in the liquid cell deflect as a self-assembled monolayer on the microcantilever binds with probe molecules in the solution. The difference in deflection between the MHA-covered probe microcantilever and the HDT-covered reference microcantilever was used to compensate for thermal drift. The deflection difference clearly increases with increasing pH in the solution. It was shown that when the pH values of the PBS solutions are high, there were large variations in the deflection of microcantilevers, whereas there were small variations for low pH value. The experimental results show that the microcantilever array functionalized with MHA and HDT can detect pH value with good repeatability.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.199-199
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• 2010

A back-gated MOSFET on silicon-on-insulator (SOI) substrate for pH sensor was investigated. We used concentrations of pH solution from 6 to 9. The fabricated back-gated MOSFET has current difference and threshold voltage shift by pH concentrations. Therefore, It can be used to simplification of conventional pH sensor.

• 대한화학회지
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• 제44권1호
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• pp.10-16
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• 2000

일반적으로 산성비는 이온세기가 낮아 저항이 크고 완충능이 없는 용액이다. 그러므로 산성비의 pH측정 시, 시료용액의 액간접촉전위는 이온세기의 차이로 인해 pH표준용액의 액간접촉전위와 달라서 pH 측정값에 오차가 발생될 수 있다. 실제 1998년도 대덕연구단지에 내린 빗물의 평균 전도도 값이 12.8 ${\mu}S/cm$인데 비해, pH 표준용액의 전도도 값은 약 5,980 ${\mu}S/cm$으로 이온세기의 차이가 크다. 본 연구에서는 산성비의 pH를 측정할 때 액간접촉전위로 인해 발생되는 오차를 보정하기 위해, 빗물과 비슷한 pH와 전도도를 가지는 묽은 황산의 물성조절표준물(Quality Control Standard, 이하 QCS로 표기)을 제조하여 사용하였다. QCS의 pH값을 액간접합이 없는 수소전극 시스템으로 인증한 다음, 유리전극으로 다시 pH를 측정하여 그 차이값 만큼 보정하였다. 아울려 이 방법으로 1998년도 대덕연구단지에 내린 빗물의 pH를 측정하였다.