• Journal of Ginseng Research
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• 제34권3호
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• pp.155-159
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• 2010

In the present review, the merit of ginseng in the improvement of insulin resistance has been introduced. Using the results in previous studies, we found that ginseng or ginsenoside Rh2 has the ability to reduce glucose-insulin index in rats with insulin resistance. Insulin resistance was induced by feeding of fructose-rich chow in rats. Insulin resistance was characterized by regular methods. Effectiveness of ginseng powder or extract Rh2 was identified in this animal model. Also, the application of ginseng for handling of diabetic disorders in China has been discussed. According to Chinese traditional medicine, ginseng is merit in the treatment of diabetic disorders named as Shiaw-Ker in Chinese. Therefore, it is no doubt that ginseng is helpful in the control of diabetic disorders either prevention or the treatment. Otherwise, the potential effect of ginseng on nervous functions shall be investigated in the future.

• Journal of Advanced Marine Engineering and Technology
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• 제39권5호
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• pp.536-541
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• 2015

Copper has been used extensively as an electric wire or as a base material in various types of machineries owing to its good electrical and thermal conductivity and good fabricating property, as well as its good corrosion resistance compared to iron. Furthermore, the copper-nickel alloy has significant corrosion resistance in severely corrosive environments. Although, cupro-nickel alloy shows better corrosion resistance than the brass and bronze series, this alloy also corroded in severely corrosive environments, including aggressive chloride ions, dissolved oxygen, and condition of fast flowing seawater. In this study, and annealing treatment at various annealing temperatures was carried out on the cupro-nickel (Cu-10%Ni) alloy, and the effects of annealing were investigated using electrochemical methods, such as measuring the polarization and impedance behaviors under flowing seawater conditions. The corrosion resistance increased by annealing compared to non heat treatment in the absence of flowing seawater. In particular, the sample annealed at $200^{\circ}C$ exhibited the best corrosion resistance. The impedance in the presence of flowing seawater showed higher values than in the absence of flowing seawater. Furthermore, the highest impedances was observed in the sample annealed at $800^{\circ}C$, irrespective of the present of flowing seawater. Consequently, the corrosion resistance of cupro-nickel (Cu-10%Ni) alloy in a severely corrosive environment can be improved somewhat by annealing.

• 한국표면공학회지
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• 제47권4호
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• pp.186-191
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• 2014

Double layer films which consisted of aluminum(Al) and magnesium(Mg) have been prepared by e-beam deposition. The structure, alloy phase, and corrosion resistance of the prepared films were investigated before and after heat treatment. The first (bottom) layer fixed with Al, and the thickness ratio between Al and Mg layers has been changed from 1 : 1 to 5 : 1, respectively. Total thickness of Al-Mg film was fixed at $3{\mu}m$. The cold-rolled steel sheet was used as a substrate. Heat treatment was fulfilled in an nitrogen atmosphere at the temperature of $400^{\circ}C$ for 2, 3 and 10 min. Surface morphology of as-deposited Al-Mg film having Mg top layer showed plate-like structure. The morphology was not changed even after heat treatment. However, cross-sectional morphology of Al-Mg films was drastically changed after heat treatment, especially for the samples heat treated for 10 min. The morphology of as-deposited films showed columnar structure, while featureless structure of the films appeared after heat treatment. The x-ray diffraction data for as-deposited Al-Mg films showed only pure Al and Mg peaks. However, Al-Mg alloy peaks such as $Al_3Mg_2$ and $Al_{12}Mg_{17}$ appeared after heat treatment of the films. It is believed that the formation of Al-Mg alloy phase affected the structure change of Al-Mg film. It was found that the corrosion resistance of Al-Mg film was increased after heat treatment.

• Journal of the Korean Wood Science and Technology
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• 제46권2호
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• pp.155-165
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• 2018

The objective of the research was to evaluate the effect of particle pre-treatment on physical, mechanical, and durability of jatropha fruit hulls (JFH) particleboard. The pre-treatments included were immersing in cold water, hot water, and acetic acid solution. After each treatment, the particles were dried up to 3% moisture content. Urea-formaldehyde (UF) resin was used to fabricate particleboards with board size, thickness and density target of 25 cm by 25 cm, 0.80 cm, and $0.70g/cm^3$, respectively. Board pressed at $130^{\circ}C$ for 10 minutes, and $25kg/cm^2$ pressure. The evaluation of particleboard followed the JIS A 5908-2003. Whilist their resistance to subterranean termite test (mass loss, mortality, antifeedant value and feeding rate) refers to the Indonesian standard (SNI 01.7207-2006). The physical and mechanical properties of particleboards showed that all pre-treatments decreased the pH of particles. Overall, all particle immersing treatments resulted of better physical and mechanical properties of particleboard than those of untreated ones. The acetic acid treatment resulted the best physical and mechanical properties of particleboard. Based on the mass loss of JFH particleboard, hot water and acetic acid treated particleboards were classified into weak resistance to subterranean attack. The other two treatments were classified into very weak resistance. Hot water treated particleboard provided the highest mortality and antifeedant as much as 87.40% and 34.20%, respectively. Based on antifeedant classification, hot water treated particleboards were classified into moderately strong resistance, while other treatments were categorized into weak resistance. The lowest feeding rate value ($45.30{\mu}g/termite/day$) was attained by hot water treatment.

• 한국해양공학회지
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• 제25권6호
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• pp.56-59
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• 2011

The demand for cold rolled steel (CR) for structural members is gradually increasing. If no surface treatment (coating for corrosion resistance) for CR is conducted, its use is very limited because CR is vulnerable to corrosion. Therefore, we need to develop a coating solution to provide high corrosion resistance for CR. In this study, an organic/inorganic coating solution with Si and Ti (Si polysilicate 7 wt.% + Urethane 13 wt.% + Ti amorphous 0.5 wt.%; LR-0727(1)) was used to evaluate the corrosion resistance of CR under a salt spray test. The specimens with the LR-0727(1) coating were heat treated in a drying oven at $120{\sim}210^{\circ}C$for 5 min. The corrosion resistance was investigated using a salt spray test of 7 h. In addition, an adhesive test was conducted. Rust showed under a heat treatment of $150^{\circ}C$, but no vestiges were found over $160^{\circ}C$. The specimens with heat treatment at $160^{\circ}C$ or more did not experience delamination. From these results, it is considered that the temperature limit for optimum heat treatment is $160^{\circ}C$ considering energy efficiency.

• 한국콘텐츠학회논문지
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• 제12권9호
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• pp.217-225
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• 2012

본 연구는 이혈요법이 여대생의 월경통, 월경곤란증 및 피부저항변이도에 미치는 효과를 규명하기 위해 시도된 비동등성 대조군 전후실험연구이다. 충남과 경북의 여대생 31명, 33명을 각각 실험군과 대조군으로하여 실험군에게는 이개의 상응점에 이혈지압구를 3일간 붙이고 지압하는 중재를 5주간 10회 적용하였고, 대조군에게는 지압구를 제거한 테이프를 부착한 후 그 결과를 비교하였다. 사전과 사후 평균차이 비교결과 월경기간 중 최대통증, 부정적 정서, 피부저항에서 유의한 차이를 나타내어 이혈요법이 월경통과 월경곤란증에 효과가 있음을 확인하였다.

• 한국표면공학회지
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• 제49권2호
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• pp.202-210
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• 2016

This study was intended to investigate the effect of the amount of magnesium addition and heat treatment in the Al-Mg coating film in order to improve corrosion resistance of aluminum coating. Al-Mg alloy films were deposited on cold rolled steel by physical vapor deposition sputtering method. Heat treatment was fulfilled in an nitrogen atmosphere at the temperature of $400^{\circ}C$ for 10 min. The morphology was observed by SEM, component and phase of the deposited films were investigated by using GDLS and XRD, respectively. The corrosion behaviors of Al-Mg films were estimated by exposing salt spray test at 5 wt.% NaCl solution and measuring polarization curves in deaerated 3 wt.% NaCl solution. With the increase of magnesium content, the morphology of the deposited Al-Mg films changed from columnar to featureless structure and particle size was became fine. The x-ray diffraction data for deposited Al-Mg films showed only pure Al peaks. However, Al-Mg alloy peaks such as $Al_3Mg_2$ and $Al_{12}Mg_{17}$ were formed after heat treatment. All the sputtered Al-Mg films obviously showed good corrosion resistance compared with aluminum and zinc films. And corrosion resistance of Al-Mg film was increased after heat treatment.

• Tuberculosis and Respiratory Diseases
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• 제66권3호
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• pp.198-204
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• 2009

연구배경: 다제내성결핵 치료에서 감수성으로 증명된 1차 항결핵제는 가장 항결핵효과가 큰 약제로 알려져 있다. 본 연구는 다제내성결핵 환자에서 표준 1차 항결핵제사용 후 1차 항결핵제에 대한 추가 내성 획득의 빈도와 그 위험 인자를 알아보고자 시행되었다. 방 법: 2004년 1월에서 2008년 5월까지 국립마산결핵병원에서 약제감수성 검사가 보고되기 전 표준 1차 항결핵제로 치료받은 다제내성결핵 환자 중에서 1차 항결핵제 치료 전과 1차 항결핵제 치료 후의 연속된 두 시점의 약제 감수성 검사 결과가 모두 있는 환자를 대상으로 하여 의무기록을 후향적으로 검토하였다. 결 과: 표준 1차 항결핵제로 치료 받은 41명 중 14명 (34.1%)에서 ethambutol (EMB) 혹은 pyrazinamide (PZA)에 대한 추가 내성이 획득되었다. 치료 전 isoniazid (INH), rifampicin (RFP)에만 내성을 보였던 11명 중 3명(27.3%)에선 EMB와 PZA에 동시 내성, 3명(27.3%)에선 PZA에 추가 내성이 획득되었다. INH, RFP, EMB에 내성을 보인 18명 중 6명(33.3%)에서 PZA에, INH, RFP, PZA에 내성을 보인 6명 중 2명(33.3%)에서 EMB에 추가 내성이 획득되었다. 대상 환자 중 10명(24.4%)에서 1차 항결핵제 치료 전 내성이었던 약제가 치료 후 감수성으로 전환되었다. 추가 내성획득과 연관된 통계학적으로 유의한 위험인자를 발견할 수 없었다. 결 론: 우리나라의 다제내성결핵 치료에서 1차 항결핵제는 추가 획득 내성의 위험을 고려하여 주의 깊게 사용해야 할 것으로 사료된다.

• Corrosion Science and Technology
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• 제15권4호
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• pp.166-170
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• 2016

The combined process of porous type anodizing and desiccation treatment was applied to improve wettability of A1050 aluminum alloy. The water contact angles of anodized samples were increaseds considerably with desiccation treatment. However, there was no considerable effect of polishing and anodizing time on water contact angle. The corrosion behavior with the treatments was investigated electrochemically. The corrosion resistance of the samples in 3.5 mass% NaCl solutions increased with higher contact angle. Anodized and desiccated samples showed better corrosion resistance than un-desiccated samples around rest potential region.

• KSTLE International Journal
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• 제2권1호
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• pp.17-21
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• 2001

Surface treatment technologies are frequently used to improve mechanical properties of surface layers of machinery components in many practical situations. Surface hardness of piston in the oil hydraulic piston pumps is very important about wear resistance. To improve hardness, wear resistance of the oil hydraulic axial piston pump, it is needed to know the surface layer characteristics in the sliding contact parts. This paper reports an experimental study on surface treatment characteristics in the piston of the oil hydraulic axial piston pump. We investigated the surface wear of a piston between untreated and nitriding-treated surfaces. We obviously observed that the surface hardness of piston in the oil hydraulic axial piston pump plays an important role to have wear resistance and remain a longer life.