• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.45-63
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• 1994

128 freshly extracted human molars were used to study the interaction between dentinal smear layer removal with various agents, and the shear bond strength of a light cured glass ionomer cement to dentin. It was proposed that the removal of smear layers using acidic cleaners followed by incorporation of Fe mordant with dentin could enhanced the infiltration of monomer component in light curing glass ionomer cement and resulted in a high bond strength. For the first treatment process for removal of smear layers on the surfaces of dentin, 50 % citric acid, 10% maleic acid and 10 % phosphoric acid were used, and for the second treatment process, 15% ferric chloride, 6.8% ferric oxalate or 30% potassium oxalate were used. Distilled water was used as a control. After double sequential treatment on dentin, a light curing glass ionomer cement was bonded to dentin. After being immersed in water at 31'C for 24 hours, shear bond strengths were measured Instron testing machine(Model No.4202, USA). Surface changes were also observed using SEM (Hitachi, S-2300, Japan) after treatment process with each agents. The following conclusions were drawn : 1. Dentin surface cleaned with maleic acid and treated with ferric oxalate showed the highest bond strength with light curing glass ionomer cement. 2. Bond strengths of glass ionomer cement to dentin treated with maleic acid or citric acid were the highest, and that treated with phosphoric acid showed the lowest. 3. The effect of ferric oxalate on shear bond strength to dentin was always higher than that of ferric chloride. 4. The smear layers were clearly removed and the orifices of dentinal tubules were opened widely by the citric acid, maleic acid and phosphoric acid. 5. The orifices of dentinal tubules opened after using the first solution were closed with the treatment of ferric chloride. 6. The precipitate like crystals were formed on dentin surfaces and tubules, but a significant decrease in bond strength of glass ionomer cement to dentin surface treated with potassium oxalate.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.1
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• pp.33-44
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• 1988

For the purpose of examining the effects of simulated acid rain on the chemical properties of the experimental soil in Pinus densiflora seedlings and Forsythia koreana rooted cuttings, the experimental design of randomized block arrangement with three replications was implemented in the experimental field of Yesan National Agricultural Junior College. One-year-old Pinus densiflora seedlings and Forsythia koreana cuttings were planted in the pots filled the mixed soils (nursery soil: forest soil of siliceous sandy loam = 1 : V/V)in the early spring of 1985. The regime of artificil acid rain, in terms of spray frequency per monthly and spray amount at single treatment per plot, was simulated on the basis of climatological data averaged from 30 years records. Simulated acid rain (pH 2.0, pH4.0, and pH 5.5 as control) containing sulfuric and nitric acid in the ratio of 3:2 (chemical equivalant basis) diluted ground water, were treated on the experimental plants under condition of cutting off the natural precipitation with vinyl tunnel, during the growing season (May 1 to August 31) in 1985. THe results obtained in this study were as follows; 1. Soil acidity was dropped, and exchangeable aluminum contents in the soil was dramatically increased in both species, with decreasing pH levels of acid rain. 2. Exchangeable potassium, clacium, magnesium contents, and base saturation degree of the soil were highly drcreased in two species as the pH levels of acid rain decreased. 3. In two species, sulfate concentrations in the soil were decreased of pH 4.0 treatment, and remarkably increased at pH 2.0 treatment of acid rain in comparison with control. 4. Total nitrogen and available phosphate contents of the soil were not affected by acid rain treatment in the both species, and Fe contents at pH 2.0 treatment were highest among three acid rain treatments.

• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.346-358
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• 1994

In this paper, the current knowledge on the formation of acid rain and its effect on vegetation are reviewed. The pollutants which were emitted into the air are oxidized by photochemical reaction and affect the vegetation by dry and wet deposition. Acid rain at pH 4.0 affected sensitive plants and when it was below pH 3.0, visible symptoms developed in most of the crops. The acid rain treatment at pH 2.0 decreased dry weight, leaf area and chlorophyll contents in soybean but it increased rate of photosynthesis and respiration rate. Rain treatment at pH 2.8 increased ethylene production, but it’s not a suitable indicator of sensitivity to acid rain. At pH 2.0 treatment, the contents of soluble Mn and Al were increased but the cultivated soil pH at upper layer(0-5cm) was significantly decreased. The pertubation of glandular trichome which is existed along the vein was developed at all treatment except the control(pH 6.0) and non-treatment. Histological pertubation of spiked trichome and disintegration of chloroplast were developed only on the leaves of sesame treated with SAR(simulated acid rain) of pH 2.0.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.359-360
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• 2002

A bacterial strain able to degrade terephthalic acid (TPA) was isolated and identified to belong to the Corynebacterium sp. It was named Corynebacterium sp. YT-14. When stirred loop bioreactor was used in a batch type system for removing terephthalic acid from weight loss treatment wastewater and complex dyeing process wastwater, the removal efficiency of terephthalic acid was 85.4% after 7 days of treatment of the weight loss treatment wastewater, while no residual terephthalic acid was detected after 3 days of treatment of the complex dyeing process wastewater

• Journal of Veterinary Clinics
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• v.22 no.2
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• pp.108-113
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• 2005

This study was performed to investigate the growth rate, hematological and serological changes of the rats when they were fed with the high fat diets supplemented with or without the tannic acid for five weeks. Thirty-two Sprague-Dawley male rats(235.7\pm10.7g\;of\;body\;weight)$ were randomly divided into four groups, control group and three treatment groups(T1, T2 and T3). Rats in control group were fed with the high fat diet containing $15\%\;lard,\;1\%$ cholesterol and $0.5\%$ sodium cholate(wt/wt) which was modified from the formula of American Institute of Nutrition (AIN)-76 diet and rats in treatment groups were fed with above diet supplemented with $0.25\%(T1),\;0.5\%(T2)$ or $0.75\%(T3)$ of tannic acid(wt/wt), respectively. The supplementation of tannic acid(TA) did not affect the final body weight, gain of body weight and feed intake of rats in both control and treatment groups. The numbers of red blood cells, hemoglobin concentrations and hematocrit values in blood of rats showed no significant differences between control group and treatment groups. The glucose concentration and albumin/globulin(A/G) ratio of rats in treatment groups were slightly lower than that of control group without significance. The values of total protein, albumin and globulin showed no significant differences between control group and treatment groups. The values of total cholesterol, low density lipoprotein­cholesterol and atherogenic index in sera of rats in treatment groups were much lower than that of control group without significance. The values of triglycerides in sera of rats in T3 group were significantly lower than that of control group (p<0.05). The values of AST and ALT in sera of rats in T3 group were significantly lower than that of control group (p<0.05). Thus supplementation of tannic acid to high fat diet could be effective to reduce the serum lipid levels such as total cholesterol, high density lipoprotein-cholesterol and triglycerides which were regarded as to cause the cardiovascular diseases.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.695-701
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• 2011

The study was carried out to investigate the effect of lighting regimes on performance and meat quality of broiler. A total of 912 chicks was divided into 2 groups with male (3 replications/group, 34 heads/replication) and female (3 replications/group, 42 heads/replication). Treatments were control (C, natural lighting), T1 treatment (24L), and T2 treatment (1~2d, 24L; 2~4d, 23L+1D; 4~16d, 16L+8D; 16~21d, 18L+6D; 21~42d, 23L+1D) by lighting regimes. Lysine content of male chicken meats at T2 treatment was lower compared to that of other treatments (p<0.05). There was no significant difference in all nonessential amino acid (AA) among treatments. Methionine content of female chicken meats at T2 treatment was lower compared to that of other treatments (p<0.05). The rate of C16:0, C16:1n7, and C18:1n9 of male chicken meat at T2 treatment was higher than that of other treatments (p<0.05), while C18:2n6 was lower at T2 treatment than other treatment (p<0.05). Mono-saturated fatty acid was the highest at T2 treatment, however, polysaturated fatty acid was the lowest at that treatment (p<0.05). There was no considerable difference in fatty acid composition of female chicken meat among treatments. Finally, lighting regime didn' affect on amino acid and fatty acid contents, and used possibly on energy reduction.

• Korean Journal of Agricultural Science
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• v.36 no.2
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• pp.225-232
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• 2009

The ratio of saccharification and formation of furans during the acid hydrolysis of agar with oxalic acid and sulfuric acid were examined base on the contents of the agar and acids. The ratio of saccharification in oxalic acid appeared to be 51~59% somewhat higher than 49~61% of sulfuric acid. Formation of the furans during the acid hydrolysis increased proportional to the contents of agar and acid. The relative formation ratio was high 10~47% for furfural (FUR) and 15~29% for hydroxy-methyl furfural (HMF) in 0.5~1.25% sulfuric acid rather than those of oxalic acid. When comparing the removal efficiency of the furans using an alkali treatment, steam stripping and hydrophobic resins, FUR was eliminated 60% by the alkali treatment, 62~90% by steam stripping and 71~75% by Amberlite XAD4 and 7HP, while HMF was removed to low levels of 10.5%, 4~17% and 13~25%, respectively. The loss of reducing sugar was also observed in process of the removal of furans, and the loss rate was the level of 2~4% in alkali treatment, 11~16% in steam stripping and 7~9% in Amberlite resins.

• Food Science and Preservation
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• v.15 no.5
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• pp.754-759
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• 2008

The effect of citric acid-aqueous chlorine dioxide ($ClO_2$) treatment of radish seeds artificially contaminated with Salmonella typhimurium was studied. Radish seeds were inoculated by immersion, in more than 106 log CFU/g seed, of a suspension of S. typhimurium, dried, and stored sealed at $4^{\circ}C$ Radish seeds soaked in 200 ppm aqueous ClO2 solution for 10 min showed a bacterial reduction of 1.08 log CFU/g seed, and the lowering of microbial burden noted in seeds soaked in 2% (w/v) citric acid solution for 10 min was 2.89 log CFU/g seed. Next, radish seeds were exposed to 0.5% (v/v) glycerol solution for 10 min either before or after treatment with 200 ppm aqueous ClO2 or 2% (w/v) citric acid for 10 min. Glycerol exposure after citric acid treatment reduced bacteria by 3.46 log CFU/g seed, and glycerol treatment after aqueous $ClO_2$ treatment reduced the microbial burden by 2.14 log CFU/g seed. Both glycerol treatments yielded better elimination of S. typhimurium than did a single treatment with either citric acid or aqueous $ClO_2$. Radish seeds inoculated with S. typhimurium were treated throughout the entire growth period. Although radish seed treatment was effective, treatment by citric acid and aqueous $ClO_2$ after sprouting was not effective to eliminate S. typhimurium.

• Journal of Environmental Science International
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• v.23 no.9
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• pp.1655-1662
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• 2014

A comprehensive fractionation technique was applied to a set of water samples obtained along drinking water treatment process with ozonation and biological activated carbon (BAC) process to obtain detailed profiles of dissolved organic matter (DOM) and to evaluate the haloacetic acid (HAA) formation potentials of these DOM fractions. The results indicated that coagulation-sedimentation-sand filtration treatment showed limited ability to remove hydrophilic fraction (28%), while removal of hydrophobic and transphilic fraction were 57% and 40%, respectively. And ozonation and BAC treatment showed limited ability to remove hydrophobic fractions (6%), while removal of hydrophilic and transphilic fractions were 25% and 18%. The haloacetic acid formation potential (HAAFP)/dissolved organic carbon (DOC) of hydrophilic fraction was the highest along the treatment train and HAAFP/DOC of hydrophilic fraction was higher than hydrophobic and transphilic fraction as 23%~30%, because of better removal for hydrophobic fraction both in concentration and reactivity.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.4 s.152
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• pp.607-614
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• 2006

This study was carried out to suggest the optimal spinning process condition which provides a proper range of tenacity and biodegradability as textile fibers. The effects of the melt spinning speed and heat treatment on the mechanical property and biodegradability of polylactic acid fiber were investigated. Polylactic acid(PLA) was spun in a high spinning speed of $2000{\sim}4000m/min$. Each specimen was heat-treated at $100^{\circ}C$ during 30min. Mechanical properties such as breaking stress and the degree of crystallinity were evaluated using WAXS. Biodegradability was estimated from the decrease of breaking stress, weight loss, and the degree of crystallinity after soil burial. Experimental results revealed that heat treated specimens showed higher breaking stress than untreated specimens, but the increase was not so high as was expected from the remarkable change of crystallinity by heat treatment. It was concluded that breaking stress was more influenced by spinning speed than heat treatment. In the soil burial test, however biodegradability calculated from weight loss was more influenced by heat treatment than spinning speed.