• Journal of the Korean Ceramic Society
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• v.32 no.11
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• pp.1315-1321
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• 1995

The optimal coating condition for chrominum carbide coating was selected by Taguchi method. The wear tests with coated specimens by HVOF method were performed in the temperature to 80$0^{\circ}C$. Applied normal loads were selected to be from 8N to 30N. The worn surfaces and subsurfaces were characterized by XRD, EPMA, AES and SEM. The wear track increased with increasing applied normal load, and in terms of the temperature range from 400 to $600^{\circ}C$, below that range, the wear track increased, and above that temperature ragne, the wear track decreased. The degree of oxidation caused by the test temperature and the frictional heating was responsible to the unique high temperature wear behavior chromium carbide coatings.

• Journal of Nutrition and Health
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• v.31 no.8
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• pp.1307-1314
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• 1998

Chrominum (cr) plays an important role in carbohydrate and lipid metabolism , and Cr deficiency impairs glucose tolerance and increases serum cholestero and triglyceride. The relationship of serum Cr with serum blucose and lipids was examined in 79 female college students in Choong-Nam areas. Subjects were divided into underweight , normal , and overweight groups according to their BMI. The average age, wiegth , height and BMI were 21.9yr, 55.9kg, 158.5cm and 22.6kg/$m^2$, respectively. Heights were not different between groups. Serum Cr and glucose concentrations werenot significantly different between groups. However, there was a tendency toward lowered serum Cr levels in under and over-weight groups. Serum cholesterol and LDL-cholesterol concentrations were significant lower in the underweight group than in other groups. BMI had positive correlation with LDL-cholesterol , AI and LPH , and negative corelations with HDL -cholesterol /total cholesterol ratio. Low serum Cr concentration was related to increased LDL-cholesterol and total cholesterol, and related to decreased HDL cholesterol in all groups . Therfore, serum Cr levels were lowered in abnormal weight groups and Cr may playan important role in coronrary heart diesease.

• Proceedings of the Korean Nutrition Society Conference
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• 1998.05a
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• pp.49-49
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• 1998

Chrominum(cr) plays an important role in carbohydrate and lipid metabolism and Cr deficiency impairs glucose tolerance and increase serum cholestrol and triglyceride. The relationships of serum Cr with serum glucose and lipids was examined in 79 female college students in Choong-Nam ares. Subjects were devided into underweight. normal and overweight groups according to their BM11. The average age, weight, height and BMI were 21.9yr, 55.89kg, 158.54cm and $22.62kg/m^2$, respectively. Height were not di fferent between groups. Serum Cr and glucose concentrations were not signi ficantly different between groups. However, there were tendency of increasing serum Cr level with increasing body weight. Serum cholesterol and LDL-cholesterol concentrations were significantly lower in underweight group than other groups. BM! had positive corelations wi th LDL-cholesterol, Al and LPH, and negative corelations with HDL-cholesterolltotal cholesterol ratio. Serum Cr concentration had positive corelation with serum glucose concentration and negative corelation with LDL-chloestrol and LPH.nd LPH.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.3-9
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• 1974

The role of added metal oxide in the adherence mechanism of low melting glass to several metal plates such as oxygen free high conducting copper, low carbon steel, chrominum galvanized on copper, and stainless steel was investigated. The metal oxide which added to glass were cupric oxide, ferric oxide, chromic oxide, and stainless steel oxide. The glass to that various metla oxide were added, sealed with several metal plates in the electric furnace at $650^{\circ}C$ for 5 minutes. The results as follows; 1) The interfacial reaction was promoted and strong chemical bonding with glass and metals by which the surface energy was decreased showed excellent sealing by addition of metal oxide. 2) When the interfacial reaction of glass and metals was promoted by addition of metal oxide found out that various adhernece mechanism were related to the sealing. 3) When the amount of metal oxide addition was 3-5% the excellent sealing was achieved.

• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.14-19
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• 1999

Chromosome rearrangements induced in human lymphocyte after in vitro exposure to chromium were analysed by the use of fluorescence in situ hybridization(FISH) with triple combination of composite whole chromosome-specific probe for chromosome 1, 2 and 4. Chromosome aberrations was scored by the Protocol for Aberration Identification and Nomenclature Terminology (PAINT). Stable translocation was the most frequent type of aberrations and dicentrics and insertions were also observed. Chromium treatment enhanced the frequencies of stable translocations and color junctions in a dose-dependent manners, but no distinct increase of dicentrics and insertions was seen. The ratio of the yields of translocation to the yields of dicentric varied between 13 to 27. The presents results demonstrate fluorescent in situ hybridization (FISH) is useful for detecting chromosomal rearrangements induced by chromium.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.2
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• pp.47-55
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• 1995

When the low heavy oil is using as fuel oil to the diesel engine, some problems such as corrosion resistance, wear resistance and heat resistance are happened in diesel engine's internal material, especially the adhesive wear of piston ring groove was occurred as a important problem. Therefore to prevent adhesive wear of its groove, the surface of its groove used to be electroplated with Chrominum and for its Chromium electroplating, Fe anode is being used until nowadays because of its Special shape. However in case of using Fe anode, there were some problems such as deterioation of solution, property of Chromium film, and condition of coation. In this paper Pb anode electroplated withPb to the steel plate was investigated for its Chromium electroplating for Pb's high corrosion resistance in acid solution, and Pb anode is not dissolved compared with Fe anode and deterioration degree of solution in case of Pb anode is smaller than that of Fe anode and also property of Chromium film was better than that of Fe anode. Moreover it was known that the optimum cathodic current density for Pb electroplating to steel plate as insoluable anode for Chromium coating of piston ring groove is 30mA/$cm^2$ by experimental results obtained.

• Nutritional Sciences
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• v.3 no.1
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• pp.42-46
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• 2000

The purpose of this study was to examine the intake of Cr, Cu, and Zn, which play important roles in lipid metabolism, and the relationship of these microminerals with serum lipids of healthy college living in the Choongnam area. The nutritional status of the subjects(35 women) was evaluated based on anthropometric measurements, 24-hr dietary recall for 3 days. Three-day meals and fasting blood were collected to analyze Cr, Cu, and Zn. The mean age, height, weight and BMI were 20 years, 158 cm, 55kg and 22.42kg/$m^2$ respectively. The mean daily energy intake was 85.9% of RDA for Koreans. The ratio of energy from carbohydrate, protein and fat was 60 : 24 : 16. The mean daily intake of Cr, Cu, and Zn was 60.07 $\mu\textrm{g}$/day, 2.64 mg/day, and 11.35 mg/day, respectively. The mean serum levels of Cr, Cu, and Zn were 143$\mu$g/dl, 81.34$\mu$g/dl, adn 101.54$\mu$g/dl, respectively. The mean serum levels of total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol were 158.56mg/dl, 29.27 mg/dl, 56.00mg/dl, 6.12mg/dl, respectively. In conclusion, the subjects of the present study were healthy and consumed normal levls of dietary Cr, Cu and Zn, which play roles in lipid metabolism. Therefore, serum lipids of the subjects were all in the normal range. There was no significant correlation between dietary microminerals and serum lipids.