• Journal of the Korean institute of surface engineering
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• v.57 no.1
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• pp.14-21
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• 2024

For this study, CrAlN multilayer coatings were deposited on SKD61 substrates using a multi-arc ion plating technique. The structural characteristics of the CrAlN multilayer coatings were evaluated using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). Additionally, the adhesion of the coatings was assessed through scratch testing, and the mechanical strength was evaluated using nanoindentation and tribometric tests for frictional properties. The results show that the CrAlN multilayer coatings possess a uniform and dense structure with excellent mechanical strength. Hardness measurements indicated that the CrAlN coatings have high hardness values, and both the coating adhesion and wear resistance were found to be improved compared to CrN. The addition of aluminum is anticipated to contribute to enhanced durability and wear resistance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.123-127
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• 2011

This study was conducted to decrease the microbial hazard in kimchi saline water with microwave plasma sterilization system and to evaluate the inactivation of foodborne pathogens by the microwave plasma sterilization system as a non-thermal treatment. Contamination of coliform, Escherichia coli, and yeasts and molds were detected in the used saline water, and the microbial populations increased as the saline water was reused repeatedly. The $D_{10}$-values of E. coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes by the microwave plasma sterilization system were 0.48, 0.52, and 0.45 cycle, respectively. In addition, the microbial populations of coliform, E. coli, Salmonella spp., total aerobic bacteria, and yeasts and molds in the used kimchi saline water were significantly decreased by treating the saline water using the microwave plasma sterilization system. Therefore, these results suggest that microwave plasma sterilization system can be useful in improving the microbial safety of the used saline water.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.3
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• pp.396-402
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• 2005

Three experiments were conducted to determine the effects of dietary arginine concentrations on plasma free amino acid (PAA) concentrations in rainbow trout, Oncorhynchus mykiss (Walbaum). The first experiment was conducted to determine appropriate post-prandial and food deprivation sampling times in dorsal aorta cannulated rainbow trout averaging 519${\pm}$9.5 g (mean${\pm}$SD) at $16^{\circ}C$. Blood samples were taken at 0, 2, 3, 4, 5, 6 and 24 h after feeding (0 and 24 h blood samples were taken from the same group of fish). PAA concentrations increased by 2 h post-feeding and the concentration of all essential amino acids except histidine peaked at 5 h and returned to 0 time values by 24 h. In the second experiment dorsal aorta cannulated rainbow trout averaging 528${\pm}$11.3 g (mean${\pm}$SD) were divided into 6 groups of 4 fish to study the effect of dietary arginine levels on PAA. After 24 h food deprivation, each group of fish was fed one of six L-amino acid diets containing graded levels of arginine (0.48, 1.08, 1.38, 1.68, 1.98 or 2.58%) by intubation. Blood samples were taken at 0, 5 and 24 h after feeding. Post-prandial (5 h after feeding) plasma-free arginine concentrations (PParg) showed a breakpoint at 1.03% arginine in the diet and post-absorptive (24 h after feeding) plasma free-arginine concentrations (PAarg) showed a breakpoint at 1.38% arginine. PAarg increased linearly from fish fed diets containing arginine between 0.48% and 1.38%, and the concentrations remained constant from fish fed diets containing arginine at or above 1.38%, but were all below PParg at all time points. Results of the third experiment confirm the results that PParg concentrations from fish fed arginine deficient diets were higher than PAarg (0 or 24 h values). Thus, in contrast to mammals and birds, the PParg when arginine is present in the diet as the most limiting amino acid such that it severely limits growth, increases in plasma rather than decreases.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.316-329
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• 2012

In this paper, optimum design process of ICP (Inductively Coupled Plasma) torch, which has been used widely in aerospace application, such as supersonic plasma wind tunnel, is presented. For this purpose, the behaviors of equivalent circuit parameters (equivalent resistance and inductance, coupling efficiency) were investigated according to the variations of torch design parameters (frequency, $f$, confinement tube radius, $R$ and coil turn numbers, $N$) in the basis of analytical and numerical MHD (Magneto Hydro-Dynamics) models combined with electrical circuit theory. From the results, it is found that equivalent resistance is increased with the increase of $f$ values but vice versa for equivalent inductance. For elevated values of $R$ and $N$, however, both parameters tend to increase. Based on these observations, ICP torch with a power level of 10 kW can be optimized at the design ranges of $f$=4~6 MHz, $R$=17~25 mm and $N$=3~4 to maximize the electrical coupling efficiency, which is the ratio of equivalent resistance to equivalent inductance.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.199-206
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• 2001

The purpose of study was to compare the plasma arc light with the halogen light in compostie resin curing. Three composite resin materials(Z-100, 3M, USA; Tetric Ceram, Vivadent, Liechtenstein; SureFil, Dentsply, USA) were filled in the teflon molds (4mm in diameter and 2, 3, 4, 5mm in thickness) and cured with either the conventional low-intensity light curing unit with a halogen lamp (Optilux 360, Demetron, U.S.A.) for duration of 40 seconds or with the high-intensity light curing unit with a plasma arc lamp (Flipo, Lokki, France) for duration of 3, 6, and 9 seconds. The intensity of halogen light was about $370mW/cm^2$ and that of plasma light was about $1,900mW/cm^2$. After one week, the surface hardnesses of both the top and the bottom of the resin samples were measured with a microhardness tester(MXT70, Matsuzawa, Japan). There were significant differences in the hardness between the top and the bottom of the resin samples except the 2mm thickness samples cured by halogen light for 40s or by plasma light for 9s. There was no significant difference between the hardness values of the top surfaces of the thickness groups. The hardness values of the bottom surfaces decreased as the curing time decreased and as the thickness of resin samples increased, and the three kinds of resin composites showed similar patterns. The results suggest that the halogen light for 40 seconds might be able to cure greater depth of resin composites than the plasma light for 3, 6, or 9 seconds.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.5
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• pp.396-405
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• 2001

Osseointegrated implants are used for the fixation of dental prosthesis with good long-term clinical results. In an attempt to improve the quantity and quality of the bone-implant interface, numerous implant modification have been used. Implants surface modifications have been used such as titanium-plasma sprayed, hydroxyapatite-coating, sandblasted, sandblasted and acid-etched, acid-etched. Rough surface implants have greater implant surface area and enhance the bone-implant interface and improve stabilization. The purpose of present study was to evaluate light microscopic and scanning microscopic examinations and removal torque value of newly developed calcium phosphate blast and acid-etched implant in the femur of rabbits. Titanium plasma sprayed(TPS) implant served as controls. After 12 weeks of healing of the femurs of 12 rabitts, the implant-containing segments of femur were removed on bloc and bone block including sections. Histologic examination and histomorphometric and removal torque values comparision were made for two implants. Obtained results are follows: 1. Newly developed calcium phosphate blasted and acid-etched implants were in close contact with bone under light microscopic examinations. 2. New implants showed mean bone-to implant contact 59.8%, whereas TPS implants showed mean bone-to implant contact 54.5% (statistically no difference p<0.05). 3. New implants showed mean bone density 56.7%, whereas TPS implants showed mean bone density 49.2% (statistically difference p<0.05). 4. New implants demonstrated mean removal torque values 40.5Ncm, whereas the mean removal torque values of TPS implants ranged 39.3Ncm. No statistical differences(p<0.05) were observed between two groups of implants nor was there any difference between the two implants at the clinical level.

• Journal of Korean Medicine for Obesity Research
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• v.9 no.1
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• pp.59-69
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• 2009

Objectives This study was designed to evaluate the difference of between Kyungohkgo and Kyungohkgo Ga Nokyong effects of growth Methods We divided male Spraque-Dawley rats into 6 groups. They were Normal group, Growth deficiency rat with insufficient nutrition diet group, Growth deficiency rat with 0.1% Kyungohkgo group, Growth deficiency rat with 0.2% Kyungohkgo group, Growth deficiency rat with 0.1% Kyungohkgo Ga Nokyong group and Growth deficiency rat with 0.2% Kyungohkgo Ga Nokyong group. They were administered for 5 weeks. We measured body weight, serum growth hormone, insulin-like growth factor and thyroid stimulating hormone, RBC, concentration of Hb and PCV ratio, total WBC and its composition, the values of plasma glutamic oxaloacetic transaminase(GOT) and glutamic pyruvic transaminase(GPT) activities. Results 1. In body weight, Kyungohkgo 0.1%, Kyungohkgo Ga Nokyong 0.1%, 0.2% groups were showed sighnificantly different than control group. But That groups were not showed significantly different than each others. 2. In serum growth hormone, insulin-like growth factor and thyroid stimulating hormone, we obtained the results of tendency to increase in Kyungohkgo Ga Nokyong group, however these values showed no significantly different. 3. In the counts of RBC, Kyungohkgo group and Kyungohkgo Ga Nokyong group were showed significantly different than control group. But these values showed no significantly different. In the concentration of Hb, Kyungohkgo Ga Nokyong 0.2%group was showed significantly different than control group. Kyungohkgo Ga Nokyong 0.2% group and Kyungohkgo 0.2% group were showed significantly different than control group. 4. The counts of total WBC and its composition showed no significantly different in all treatment groups. 5. The values of plasma glutamic oxaloacetic transaminase(GOT) and glutamic pyruvic transaminase(GPT) activities showed no significantly different in all treatment groups. Conclusions So Kyungohkgo Ga Nokyong and Kyungohkgo have an effect of promoting growth of rats. And We know that the effect of Kyungohkgo Ga Nokyong is better than Kyungohkgo.

• The Korea Journal of Herbology
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• v.24 no.3
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• pp.79-86
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• 2009

Objectives : The present study investigated Inflammatory effect of Coptidis Rhizoma in lipopolysaccharideexposed rats and Raw 264.7 cells. Methods： The plasma concentration of IL-1$\beta$, IL-6 and TNF-$\alpha$ peaked at 5 h after LPS injection, and the values of the Coptidis Rhizoma extract groups were lower than those of the control group. In the increment of cytokines concentration at 2 h and 5 h after LPS injection, the Coptidis Rhizoma groups were lower than that of control group. The plasma concentration of IL-10 peaked at 5 h after LPS injection, and the values of the Coptidis Rhizoma extract groups were higher than those of the control group. In the increment of cytokines concentration at 2 h and 5 h after LPS injection, the Coptidis Rhizoma groups were higher than that of control group. Liver cytokines measurement was done at 5 h after LPS injection. The concentration of liver IL-1$\beta$ and IL-6 in the Coptidis Rhizoma groups was lower than that of the control group. The concentrations of liver TNF-$\alpha$, and IL-10 showed no significant differences among all the treatment groups. Results： In the studies of lipopolysaccharide-exposed Raw 264.7 cells, the concentration of IL-1$\beta$, IL-6 and TNF-$\alpha$ in the lipopolysaccharide-exposed cells groups was higher than that of control group (normal group), and in the lipopolysaccharide-exposed cells groups, these values showed a tendency to decrease in the Coptidis Rhizoma groups. The concentration of IL-10 in the lipopolysaccharide-exposed cells groups was higher than that of control group (normal group), and in the lipopolysaccharide-exposed cells groups, the values showed a tendency to increase in the Coptidis Rhizoma groups. Conclusions： These results indicate that the Coptidis Rhizoma extracts have an functional material for Inflammatory activities.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.3
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• pp.275-280
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• 1995

The effect of supplemented high protein diet intake on renal urea regulation in swamp buffalo was carried out in the present experiment Five swamp buffalo heifers weighing between 208-284 kg were used for this study. The animals were fed with a supplementary high protein diet and renal function and kinetic parameters for urea excretion were measured. This was compared to a control period where the same animals had been fed only with paragrass and water hyacinth. For 2 months the same animals were fed a mixed of paragrass, water hyacinth plus 2 kgs of a high protein supplement (protein 18.2% DM basis) per head per day. In comparison to the control period, there were no differences in the rate of urine flow, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma urea concentration and filtered urea. In animals supplemented with high protein intake mean values of urea clearance, excretion rate and the urea urine/plasma concentration ratio markedly increased (p < 0.05) while renal urea reabsorption significantly decreased from 40% to 26% of the quantity filtered. In this same study group urea space distribution and urea pool size increased which coincided with an increase in plasma volume (p < 0.05). Plasma protein decreased while plasma osmolarity increased (p < 0.05). Both urea turnover rate and biological half-life of $^{14}C$-urea were not affected by a supplementary high protein intake. The results suggest that animals supplemented with high protein diets are in a state of dynamic equilibrium of urea which is well balanced between urea excreted into the urine and the amount synthesized. The limitation for renal tubular urea reabsorption would be a change in extra-renal factors with an elevation of the total pool size of nitrogenous substance.

• Journal of Nutrition and Health
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• v.31 no.4
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• pp.708-715
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• 1998

Chronic abuse of alcohol can lead to the development of folate deficiency due to inadequate folate intaike, excessive urinary excretion and from effects of ethanol on folate absorption and metabolism . To investigate the effects of alcohol and folate intake on folate metabolism, the rates were raised for 4 and 10 weeks on experimental diets containing 0, 2 8mg folate/kg diet, and were administered 50% ethanol(1.8$m\ell$/kg body weight) three times a week intragastrically. Plasma and tissue folate concentrations were found to be significantly influenced by dietary folate level. In animals fed on folate-deficient diet, concentrations of folate in the plasma, liver and kidney were decreased by 60-89% compared to those on folate-adequate diet, and ther values were further decreased with experimental period. Folate supplementation increased plasma and tissue folate levels significantly by 16-78% compared to those on folate-adequate diet, and the folate levels in the plasma and liver were affected most by the supplementation. Alcohol administration did not seem to influence folate status in the body significantly when animals were raised on folate-deficient diet. However, when rats were fed folate-adequate or folate-supplemented diet, alcohol was shown to decrease plasma and tissue folate concentrations. Among the animals receiving alcohol, folate concentrations in the plasma and tissues were significantly higher when animals fed folate-supplemented diet compared to folate adequate diet. Alcohol seems to exert differential effects on urinary foalte excretion by experimental period it increased urinary folate in the 4-week period, but lowered foalte excretion in the urine when the experimental period was extended to 10 weeks. Alcohol did not seem to influence folate excretion in the feces. These results indicate that folate supplementation might be beneficial in ameliorating the inadequate folate status that might occur with chronic alcoholism.