• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.197-198
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• 2011

• Current Research on Agriculture and Life Sciences
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• 제7권
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• pp.73-81
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• 1989

본 실험은 견직물의 염색시에 많이 사용되는 Acetic Acid, Sulphuric Acid 및 Formic Acid등의 산성화학약제 처리가 생사의 물리적 성질에 미치는 영향을 규명한 것으로서 그 결과는 다음과 같다. 생사의 강력(g/d)은 공시 3개약제 다같이 온도 및 pH 변화에 따른 차이를 인정할 수 없었다, 생사의 신도(%)는 Acetic Acid 및 Sulphuric Acid $40^{\circ}C$ pH 3에서 Formic Acid $80^{\circ}C$ pH 4에서 유의차 있게 저하되었다.

• 대한간호학회지
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• 제29권6호
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• pp.1284-1293
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• 1999

This study was designed to investigate the effect of aromatherapy on skin xerosis and pruritus in patients undergoing maintenance hemodialysis. Twenty one subjects of this study were selected from St. Paul's Hosipital in Seoul. All the subjects were received the mineral oil massage at the arm without fistular three timesper week for 4 weeks. After 2 weeks period of wash-out, the subjects were received the aromatherapy of lavender and tea tree essence oil in the same way. This study was carried out from March 20 to June 13, 1998. Pruritus score, skin pH and stratum corneum hydration were measured before and after each treatment. But, biochemical parameters were measured before the treatment of the mineral oil massage, after the treatment of the mineral oil massage and the aromatherapy. Data of this study were analyzed by paired t-test, repeated measures ANOVA, Bonferroni multiple comparisons and Pearson correlation coefficient. The results were as follows ; 1. Pruritus score was significantly decreased after the aromatherapy, while no significant change after the treatment of the mineral oil massage. Therefore, there was a significant difference in the priritus score between the two treatments. 2. Stratum corneum hydration was significantly increased after the aromatherapy, while no significant change after the treatment of the mineral oil massage. Therefore, there was a significant difference in the stratum corneum hydration between the two treatments. 3. Skin pH was significantly increased after the treatment of the mineral oil massage, while no significant change after the aromatherapy. Therefore, there was no significant difference in the skin pH between the two treatments.4. After the aromatherapy, the serum calcium was significantly increased. Whereas the serum parathyroid hormone intact was significantly decreased compared with the treatment of the mineral oil massage. But the level of the serum Ca and PTH-intact were within the normal range. 5. Stratum corneum hydration was decreased corresponding to the duration of hemodialysis, while pruritus score and skin pH showed no change corresponding to the duration of hemodialysis and the age of the subjects. The correlation of pruritus score on skin pH, stratum corneum hydration and biochemical parameters was not significant. In conclusion, this findings indicate that aromatherapy may be effective in decreasing skin xerosis and pruritus score in uremic pruritus patients undergoing maintenance hemodialysis.

• 대한소아치과학회지
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• 제34권3호
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• pp.532-542
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• 2007

연구 목적은 부정교합과 부분무치증 등의 치과 문제의 배경으로서 사람 진화에 따른 치열의 변화 양상을 고찰하는 것이었다. 사람은 분류학적으로 동물계, 척추문, 포유강, 영장목, 고등영장아목, Hominoid(상위인과), Hominid(인과), Homo(인속), sapiens(종)이다. 최초의 Hominid는 약 400만년 전에 출현한 Australopithecus로서 직립보행과 치열의 변화가 특징이었고, Homo속은 약 250만년 전에 출현한 최초의 석기 제작자 H. habilis를 시작으로, H. erectus, H. neanderthalensis 등이 나타났다가 사라지면서 현생 인류인 H. sapiens에 이르렀다. 원시포유류의 I3 C1 P4 M3의 치열은 원시영장류의 I2 C1 P4 M3, 고등영장류의 I2 C1 P3 M3, Hominoid의 I2 C1 P2 M3로 변화하였고 H. sapiens는 I2 C1 P2 M2의 치열로 변화하고 있다. Hominoid의 상자형 치열은 Australopithecus의 오메가형 치열을 거쳐 Homo의 포물선형 치열로 변화하였다. 치아의 크기가 계속 감소하였고 특히 견치의 크기와 성적 이형성이 감소하였다. 뇌 크기가 증가하고 악골의 크기가 감소함에 따라 치열은 두개관에 대해 후하방으로 이동하였다. 녹말이 풍부한 주식으로의 변화, 식품 가공, 요리 기술의 발달이 저작의 필요성을 감소시켜 치열 변화를 촉진하였다는 가설이 제기되었다. 지구 역사에서 극히 최근에 나타난 신종으로서 지구 전역에 퍼져 대량 멸종을 일으키고 있는 H. sapiens의 미래는 불투명하다. 부분무치증과 부정교합은 사람 진화에 따른 치열 변화와 관계가 있는 것으로 보이며 앞으로 증가할 가능성이 있다고 사료된다.

• 한국전기전자재료학회논문지
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• 제21권11호
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• pp.1010-1018
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• 2008

In this report, we describe the use of gold nanoparticles (AuNPs) immobilized on pH. responsive, cross-linked poly(4-vinylpyridine) (P4VP) thin films, as a potential application for pH nanosensors. The methodology is based on the variation in surface plasmon resonance of immobilized AuNPs with changing the interparticle distances, caused by the swelling/deswelling of the pH responsive P4VP polymer films. The change in optical properties of the immobilized AuNPs in response to the pH of surrounding media was investigated by a simple yet powerful tool; UV-vis absorption spectroscopy. The swelling of the P4VP chains at pH 2 causes an increase in the interparticle distances of immobilized AUNPS ($\sim20nm$) and hence leads to a blue shift of 48 nm in their surface plasmon resonance band peak. On the other hand, when the surrounding media was altered from pH 2 to 10, a red shift of absorption maxima was observed. The changes were rapid, and the effect was reversible. This system could prove to be useful in fabricating nanosensors for detecting the pH or pH changes of surrounding aqueous medium.

• Journal of Periodontal and Implant Science
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• 제32권4호
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• pp.697-709
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• 2002

The present study was performed to evaluate the effect of citric acid on the change of implant surface microstructure according to application time. Implants with pure titanium machined surface, titanium plasma-sprayed surface, and sand-blasted, large grit, acid etched surface were utilized. Implant surface was rubbed with pH 1 citric acid for $\frac{1}{2}$ min., 1 min., 1 $\frac{1}{2}$ min., 2 min., and 3min, respeaively in the test group and implant surface was not treated in the control group. Then, the specimens were processed for scanning electron microscopic observation. The following results were obtained. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two groups. 2. In titanium plasma-sprayed surfaces, round or amorphous particles were deposited irregularly. The irregularity of titanium plasma-sprayed surfaces conditioned with pH 1 citric acid was lessened and the cracks were increased relative to the application time of pH 1 citric acid. 3. Sand-blasted, large grit, acid etched surfaces showed the macro/micro double roughness. The application of pH 1 citric acid didn't change the characteristics of the sand-blasted, large grit, acid etched surfaces. In conclusion, the application of pH 1 citric acid to titanium plasma-sprayed surface is improper. And pure titanium machined surface implants and sand-blasted, large grit, acid etched surface implants can he treated with pH 1 citric acid for peri-implantitis treatment if the detoxification of these surfaces could be evaluated.

• 한국산림과학회지
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• 제87권2호
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• pp.145-152
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• 1998

산성우에 대한 수목 잎의 반응에 대한 기초연구로서 느티나무, 아까시나무, 상수리나무, 벚나무, 은행나무, 잣나무, 소나무 잎을 대상으로 여러 가지 pH(pH 2.0~pH 6.0)수준 및 시간별로 처리하여 침출수의 pH와 잎의 엽록소 함량 변화에 대한 연구를 하였을 때 다음과 같은 결과를 얻을 수 있었다. 1. 공시 수종의 잎을 pH 3.0~pH 6.0의 용액에 담그었을 때 처리 용액의 pH는 시간이 지남에 따라 수종별로 일정한 pH대로 변화하여 48시간 후에는 느티나무 pH 5.0~pH 5.5, 아까시나무 pH 5.5~pH 6.0, 상수리나무 pH 4.5~pH 5.0, 벚나무 pH 5.5~pH 6.0, 은행나무 pH 3.5~pH 4.5, 잣나무 pH 3.5~pH 4.5로 바뀌어 갔다. 그러나 소나무의 경우에는 일정한 pH대를 파악할 수 없었다. pH 2.0용액을 처리하였을 때 느티나무, 아까시나무, 벚나무에서 pH가 약간 상승하였고 다른 수종의 경우 거의 변화가 없었다. 2. 여러 가지 pH 용액 처리후 엽록소 함량 변화에 대한 실험에서 pH 2.0 용액 처리시 느티나무, 아까시나무, 벚나무에서 엽록소의 함량이 감소였다. 한편, 다른 pH 수준에서는 엽록소 함량이 거의 일정하였다. 다른 수종들에 대한 다양한 pH 처리수준 및 처리 시간에 따른 엽록소 함량변화가 거의 없었다. 이를 통하여 느티나무, 아까시나무, 벚나무 잎의 산성우 pH 상승효과가 높은 것을 알 수 있었다.

• Clinical Nutrition Research
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• 제5권3호
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• pp.172-179
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• 2016

Acid food indicators can be used as pH indicators for evaluating the quality and freshness of fermented products during the full course of distribution. Iron oxide particles are hardly suspended in water, but partially or completely agglomerated. The agglomeration degree of the iron oxide particles depends on the pH. The pH-dependent particle agglomeration or dispersion can be useful for monitoring the acidity of food. The zeta potential of iron oxide showed a decreasing trend as the pH increased from 2 to 8, while the point of zero charge (PZC) was observed around at pH 6.0-7.0. These results suggested that the size of the iron oxide particles was affected by the change in pH levels. As a result, the particle sizes of iron oxide were smaller at lower pH than at neutral pH. In addition, agglomeration of the iron oxide particles increased as the pH increased from 2 to 7. In the time-dependent aggregation test, the average particle size was 730.4 nm and 1,340.3 nm at pH 2 and 7, respectively. These properties of iron oxide particles can be used to develop an ideal acid indicator for food pH and to monitor food quality, besides a colorant or nutrient for nutrition enhancement and sensory promotion in food industry.

• Bulletin of the Korean Chemical Society
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• 제17권10호
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• pp.925-929
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• 1996

Uranyl hydrolysis precipitates were obtained by increasing pH value of aqueous uranyl solution in the range of neutral to alkaline pH value and their phase transformation during the solubility experiment under various conditions has been examined. The precipitates formed in the hydrolysis reaction of uranyl ion had a layered structure such as a meta-schoepite phase, a schoepite structure, or a mixed phase of meta-schoepite and schoepite. Phase transformation between them was strongly dependent on the pH value at which the precipitate was formed. The distance between the layers in meta-schoepite or schoepite phase was ∼7.35 Å, and it was increased with the pH value at which the precipitate was synthesized as well as the pH values of the aqueous solution. The phase transformation from a meta-schoepite to schoepite was fast for the precipitates formed at low pH values, however, it was not the case for the precipitates formed at high pH values. A small difference of pH value in aqueous solution gave a great change on its solubilities near pH 9.7, because a layered structure of the precipitates became amorphous above that pH value. Greater solubility for the precipitate formed at higher pH value can be explained from the fact that the precipitates formed at low pH value had a better crystallinity and also that the precipitates formed at higher pH value has a slower rate of crystallization.

• 한국의류학회지
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• 제20권5호
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• pp.792-800
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• 1996

The shape retention finishing provides a fabric for easiness of no-ironing after laundering. In spite of the obvious importance of the new finishing treatment, few systematic studies have been performed on the handle of the fabrics finished by the durable press process. The purpose of this research is to investigate the relationships among the mechanical properties, durable press conditions, primary hand values and the total hand value of the fabrics finished by shape retention process. In this experiment, durable press grade of unfinished fabrics decreased below 2.5, but those of finished fabrics maintained above 4, but the mechanical properties of finished fabrics did not change significantly after laundering. In finished fabrics, D.P. value were correlated with mechanical properties, but had little effects with H.V. and T.H.V. Since the evaluation of the effect of durable press process was done with the naked eyes and standard sample, we could not know exactly change o( mechanical properties, but trace the change of mechanical properties which gave influences on the durable press effects by using KES-FB System.