• Resources Recycling
• /
• v.23 no.6
• /
• pp.22-29
• /
• 2014

Recycling process of iron should be developed for efficient recovery of neodymium (Nd), rare metal, from acid-leaching solution of Nd magnet. In this study, $FeCl_3$ solution as iron source was used for preparation of iron nano particles with the condition of various factors, such as, reductant, and surfactant. $Na_4P_2O_7$ and Polyvinylpyrrolidone (PVP) as surfactants, $NaBH_4$ as reductant, and palladium chloride ($PdCl_2$) as a nucleation seed were used. Iron powder was analyzed by using XRD, SEM for measuring shape and size. Iron nano particles were prepared at the ratio of 1:5 (Fe (III) : $NaBH_4$). Size and shape of iron particles were round-form and 50 ~ 100 nm size. Zeta-potential of iron at the 100 mg/L of $Na_4P_2O_7$ was negative value, which was good for dispersion of metal particle. When $Na_4P_2O_7$ (100 mg/L), PVP($FeCl_3:PVP$ = 1 : 4, w/w) and Pd($FeCl_3:PdCl_2$ = 1 : 0.001, w/w) were used, iron nano particles which were round-shape, well-dispersed and near 100 nm-sized range. In this condition, $FeCl_3$ solution changed with spent Nd leachate solution, and then it is possible to be made round-formed iron nano particles at pH 9 and at the reaction bath over 20 L which is not include any surfactant.

• The Korean Journal of Physiology
• /
• v.17 no.2
• /
• pp.125-133
• /
• 1983

Red cell glycolytic intermediates, metabolites and metabolic ratios were studied. Glycolytic intermediates were measured in neutralized perchloric acid extracts of red cell suspensions after 3 hr incubation at $37^{\circ}C$ in the presence and absence of saponin. Adenosine triphosphate(ATP), adenosine diphosphate(ADP), pyruvate and lactate were measured by enzymatic procedures involving stoichiometric oxidation or reduction of a pyridine nucleotide. Glucose was determined using glucose oxidase after zinc hydroxide extraction. The redox state was calculated from the lactate dehydrogenase equilibrium. Adenosine triphosphatase activity(ATPase) was measured by determining the amount of phosphate released from ATP by washed erythrocyte membranes(ghost) during 20 min. incubation. Both total hydrolysis and the amount of hydrolysis that occured in the presence of ouabain were measured. The second measurement yields Mg-ATPase and represents nonspecific ATPase activity of the membranes. The difference between total and Mg-ATPase activity can be attributed to Na-K-ATPase. For the measurement of sodium fluxes, human erythrocytes were preincubated in $^{22}Na$ for 3 hr at $37^{\circ}C$, washed and suspended in a tracer-free medium. The amount of $^{22}Na$ transported out of cells at any time was determined by analysis of supernatant samples taken at various time after addition of the labeled cells to isotope-free medium. The cells and medium were separated and the radioactivity appearing in the medium was measured. From the total radioactivity in the suspension and the radioactivity appearing in the medium at known time, the rate constant for sodium release was computed. The results are summarized as follows: 1) ATP and ATP/ADP were found to increase at every concentration of saponin tested whereas ADP declined at every cone. of saponin. The increase in pyruvate and lactate were observed at every cone, of saponin and thus $NAD^+/NADH$ computed from pyruvate/lactate also increased. Glucose utilization was stimulated by saponin. 2) $Na^+-K^+-ATPase$ activities showed a biphasic response to saponin, first increasing in lower concentration and then decreasing in higher concentration of saponin. 3) The efflux of sodium was significantly increased by saponin in the range of 5 to 10 mg%. The stimulatory effect of saponin on the rate constants for active(ouabain-sensitive) sodium efflux was inhibited by addition of ouabain.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.3
• /
• pp.565-573
• /
• 2000

Sewer pipe in Korea is generally constructed with concrete pipes. Moreover, the sewer system is susceptible to the corrosion problem due to the regulation employing anaerobic treatment processes, such as domestic sewage treatment facilities, nightsoil septic tanks and so on. The objective of this study is investigated to experimental test of $H_2S$ production rate affecting corrosion of sewer pipe in Korea. In this study, tube-type and sealed-type reactor were used to examine the reactions in the microorganism suspended growth and biofilm. Furthermore. concentration changes were investigated with COD and sulfate reduction in each reactor. Sulfide production rate was $50.4mg-H_2S/g-VSS{\cdot}d$ in the sealed-type reactor and in the tube-type biofilm reactor was $2.8{\sim}18.8g-H_2S/m^2{\cdot}d$.

• Journal of Nutrition and Health
• /
• v.31 no.9
• /
• pp.1446-1456
• /
• 1998

Bones are important parts in sustaining the shape of the body, but they are also metabolic organs which undergo bone remodeling by constant bone resorption and formation. Osteoporosis, the typical metabolic bone disease, is characterized by a reduction in bone mineral density (BMD). Women more than men are at risk fir osteoporosis-related fractures, especially in the lumbar spine, wrist, and hip region. Risk of fracture depends on one's BMD, which open determined by the peak bone mass value achieved at skeletal maturity and followed by subsequent age-and menopause-related bone loss. Genetic and environmental factors are known to play a key role in bone metabolism and diet is considered as one of the important environmental factors. The purpose of the present study was to assess the status of BMD and bone mineral content(BMC) to clarify the relationships between dietary intakes and the risk of osteoporosis in adult women in Taegu. Subjects were 130 healthy females in between 20 and 69 years of age. BMD and BMC of the lumbar spine(venebrae L2-4) of the subjects were measured by dual energy X-ray absorptiometry. The average age of the subjects was 47.4${\pm}$11.7 years old, the average weight was 57.2${\pm}$8.4kg, the average age of menarche was 16.6${\pm}$1.9 years old and the average age of menopause was 48.4${\pm}$5.3 years old. The nutrient intakes of the subjects measured by the convenient method were generally lower than the level of RDA. The result of nutrient intake assessed has shown that the average energy intake was 1701${\pm}$316kca1 which is 85.1% of the RDA and the average calcium intake was 485.4${\pm}$172.3mg which is 69.3% of the RDA. The intakes of protein, vitamin A, vitamin B$_1$, niacin were greater than the RDA, whereas the remaining nutrient intakes were lower than the RDA. The average BMD of the subjects was shown to be 1.06${\pm}$1.09g/$\textrm{cm}^2$. The highest BMD of 1.24${\pm}$0.14g/$\textrm{cm}^2$ was noticed in the subjects of 30s compared to 20s, 40s, 50s, 60s. The BMD values were compared by the relative body weight(R3W) of the menopause subjects, and it was found that the underweight group had significant lower BMB while the rest of the groups did not have any differences in BMD. The most strongly correlated nutrient with BMD among the menopause subjects appeared to be calcium. The women whose Ca intakes were higher than 500mg showed the significantly higher BMD than those with Ca intakes lower than 500mg. This study suggests that the most effective way to prevent osteoporosis and to reduce the incidences of fractures seems to be minimizing bone loss through the adequate intake of calcium as well as avoiding underweight, especially in menopausal women. (Korean J Nutrition 31(9) . 1446-1456, 1998)

• Journal of Korean Society of Environmental Engineers
• /
• v.29 no.9
• /
• pp.989-996
• /
• 2007

In this study, abiotic transformation of 1-naphthol(1-NP) via oxidative-coupling reaction and its reaction products were investigated in the presence of Mn oxides. The reaction products were characterized for their relative polarity using solvent extraction experiment and reverse-phase HPLC, and for structure using CCMS and LC/MS, and for absorption characteristics using UV-Vis spectrometry. The reaction products present in aqueous phase were more polar than parent naphthol and comprised of 1,4-naphthoquinon(1,4-NPQ) and oligomers such as dimers and trimers. Hydrophilic component present in water phase after solvent$(CH_2Cl_2)$ extractions was identified as naphthol polymerized products having molecular weight(m/z) ranging from 400 to 2,000, and showed similar UV-Vis. absorption characteristics to that of foil fulvic acid. Transformation of 1,4-NPQ, which is non-reactive to Mn oxide, to the polymerized products via cross-coupling reaction in the presence of 1-NP was also verified. In this experimental conditions(20.5 mg/L, 1-NP, 2.5 g/L $MnO_2$, pH 5), the transformation of 1-NP into the oligomers and polymerized products were about 83% of initial 1-NP concentrations, and more than 30% of the reaction products was estimated to be water insoluble fractions, not extracted by $H_2O$ methanol. Results from this study suggest that Mn oxide-mediated treatment of naphthol contaminated soils can achieve risk reduction through the formation of oligomers md polymer precipitation.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.16 no.3
• /
• pp.233-244
• /
• 2006

Of many volatile organic detergents for metals, benzine(CAS No. 8030-30-6), of which the toxicity has not yet been proven, has been used as an alternative of the halide compounds in the consideration of toxic effects, global warming and the destruction of ozone layer. In order to evaluate the effects of the benzine on human body by investigating the subchronic inhalation toxicity, to obtain the basic data for establishing the criteria of exposure in working environments and to classify the hazardousness in compliance with the Industrial Safety and Health Act by evaluating the hazardousness, repeated inhalation exposure test was carried with SD rats. The rats were grouped by 10 females and males each. The repetitive inhalation exposures were carried out at 4 levels of concentration of 0 ppm, 60 ppm, 300 ppm, and 1,500 ppm, for 6 hours a day, 5 days a week, for 13 weeks. The results are described hereunder. 1. No death of the animals of the exposed and controlled groups in the test period. Not any specific clinical symptoms, change in feed intake quantity, abnormality in eye test, or change in activity were observed. 2. In the 300 ppm and 1,500 ppm groups, weight reduction in the female groups and weight increase of liver and kidney in the male groups compared with control group were observed with statistical significance(p<0.05). 3. In the blood test, the HCT increased in the male 300 ppm group and the number of hematocyte increased, MCV and MCH decreased in the male 1,500 ppm group. In the female 1,500 ppm group, the HB decreased and the distribution width of the hematocyte particle size increased. In the blood biochemistry test, the TP in the male 1,500 ppm group and the LDH in the female 1,500 ppm group were increased with statistical significance(p<0.05). 4. Under the test conditions of the present study with SD rats, the NOEL was evaluated to be from 60 ppm to 300 ppm for both male and female groups. By extrapolation, the NOEL for human who work 8 hours a day was evaluated to be from 128 ppm to 640 ppm 5. Since the NOEL evaluated in this study do not exceed 60ppm(0.184 mg/L) the test material does not belong to the classification of the hazardous substance "NOEL${\leq}$0.5mg/L/6hr/90day(rat), for continuous inhalation of 6hours a day for 90 days" nor to the basic hazardous chemical substance class 1(0.2 mg/L/6hr/90day(rat) defined by the GHS which is a criteria of classification and identification of chemical compounds. However, considering the boiling point($30-204^{\circ}C$), flashing point($-40^{\circ}C$), vapor pressure(40 mmHg), and the inflammable range(1.0 - 6.0 %), sufficient care should be taken for handling in the safety aspects including fire or explosion.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.3
• /
• pp.609-617
• /
• 2017

This experiment was carried out to enhance the availability of blackberry. Since it is difficult to use blackberry as a fresh fruit, we investigated the quality characteristics of blackberry powder obtained by various drying methods (freeze drying and hot-air drying at $40{\sim}80^{\circ}C$). The L- and b-values of freeze-dried powder was higher than hot-air dried powder. The pH (3.2) was lowest and the acidity (14.4%) was highest in freeze-dried powder. In freeze drying, the brix degree was $65.7^{\circ}Bx$, but it increased from $54.7^{\circ}Bx$ to $68.5^{\circ}Bx$ with increasing temperature during hot air drying. The total polyphenol and flavonoids contents were the highest in freeze-dried powder, at 9.3 and 6.2 mg/g, respectively. The levels increased as temperature increased in hot air drying. Anthocyanin content in freeze-dried powder was 8.51 mg/g, while it sharply decreased to 1.17~2.45 mg/g in hot-air drying. Vitamin C content in freeze drying ($979.4{\mu}g/g$) was higher than that in hot-air drying ($48.3{\sim}303.2{\mu}g/g$). The sample concentration required for 50% reduction of DPPH free radical scavenging ($RC_{50}$) was $79.7{\mu}g/mL$ in freeze drying, and showed high antioxidant activity. Also it decreased from $122.4{\mu}g/mL$ to $87.7{\mu}g/mL$ with temperature increase during hot air drying. We therefore conclude from the above results that freeze drying is more suitable for the production of blackberry powder, because this method showed high value of chromaticity, total polyphenol, flavonoid, anthocyanin content, vitamin C and antioxidant activity.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.17 no.3
• /
• pp.224-234
• /
• 2007

This study aimed to examine the harmful effects of Mn and Fe, which may be generated as dust or fume in the industrial sites, on the body and genital organs by their inhalation. It is intended to find the characteristics and differences of the hazardousness by inhaling a single and the mixed materials of Mn and Fe. Male F344 rats were divided into the control group and 3 exposed groups on the basis of the test material compound (Mn $1.5mg/m^3$, Mn 1.5 and Fe $3.0mg/m^3$, Fe $3.0mg/m^3$). The 4 groups were divided into 4 subgroups again on the basis of the exposure period (4 and 13 weeks) and the recovery period (4 and 13 weeks). The exposure condition was 6 hours a day, 5 days a week for the whole body. Clinical tests including changes in weight and feed rate, blood biochemical test, motility change, changes in the number and the amount of spermatozoon (sperm count), daily sperm production (DSP), deformity test of spermatozoon and changes in the accumulation of Mn and Fe in blood and internal organs were performed. Motility was reduced by Mn exposure. Especially, the effect of Mn was exposure period responsible. By mixing with Fe, no significant change in motility Mn and Fe accumulation in organs was observed. Sperm count and daily sperm production (DSP) were decreased by Mn. Additional effect like the reduction of sperm count and DSP, and delayed restoration of sperm count and DSP during the recovery period were observed in the mixed exposure group. These results indicate that Mn and Fe may affect the motility reduced and has male reproductive toxicity. Mixed exposure of Mn and Fe lead to synergic effects on the male reproductive toxicity.

• Korean Journal of Adult Nursing
• /
• v.17 no.1
• /
• pp.149-159
• /
• 2005

Purpose: The purpose of this study was to examine the relationship among the levels of total serum cholesterol level, blood pressure, body mass index, and lifestyle. Method: This study was designed as a descriptive correlation study. Subjects were 972 adults participated voluntarily living in GyeongNam. The height, weight, blood pressure and fasting serum cholesterol were measured. Body mass index was caculated. Information on general characteristics (age, gender, education, job, family history) and life style(cigarette, alchol, sleeping time, regular exercise, meal pattern, peppery, salty, sweetness, vegetable diet, meat diet) were collected using a questionnaire by interviewing method. Result: The mean value of total serum cholesterol was $197{\pm}36.4mg/dl$(mean; $189{\pm}36.7mg/dl$, women; $202{\pm}35.1mg/dl$). By simple analysis, the serum total cholesterol according to general characteristics features was statistically significant in age(F= 6.765, p=000) and gender (t=5.372, p=.000). Total serum cholesterol levels increased significantly with increasing BMI. The serum total cholesterol according to life style features was statistically significant in cigarette(${\chi}^2=12.12$, p=.016), exercise(${\chi}^2=6.335$, p=.042), salty taste(${\chi}^2=18.801$, p=016), vegetable diet (${\chi}^2=19.488$, p=012). The most affecting factor which total serum cholesterol factor was BMI(${\beta}=.151$, p=.000). Conclusion: The significant risk factors relating to serum total cholesterol were age, gender, BMI, smoking, and exercise. Therefore, for the reduction of serum total cholesterol level, it is recommended that nursing intervention for the prevention of obesity, change of life style should be implemented.

• Nutrition Research and Practice
• /
• v.11 no.6
• /
• pp.461-469
• /
• 2017

BACKGROUND/OBSECTIVE: Airway inflammation by eosinophils, neutrophils and alveolar macrophages is a characteristic feature of asthma that leads to pathological subepithelial thickening and remodeling. Our previous study showed that oxidative stress in airways resulted in eosinophilia and epithelial apoptosis. The current study investigated whether glutathione-containing dry yeast extract (dry-YE) ameliorated eosinophilia, goblet cell hyperplasia and mucus overproduction. MATERIALS/METHOD: This study employed $2{\mu}g$/mL lipopolysaccharide (LPS)- or 20 ng/mL eotaxin-1-exposed human bronchial epithelial cells and ovalbumin (OVA)-challenged mice. Dry-YE employed in this study contained a significant amount of glutathione (140 mg in 100 g dry yeast). RESULTS: Human bronchial epithelial cell eotaxin-1 and mucin 5AC (MUC5AC) were markedly induced by the endotoxin LPS, which was dose-dependently attenuated by nontoxic dry-YE at 10-50 ${\mu}g$/mL. Moreover, dry-YE inhibited the MUC5AC induction enhanced by eotaxin-1, indicating that eotaxin-1-mediated eosinophilia may prompt the MUC5AC induction. Oral supplementation with 10-100 mg/kg dry-YE inhibited inflammatory cell accumulation in airway subepithelial regions with a reduction of lung tissue level of intracellular adhesion molecule-1. In addition, ${\geq}50$ mg/kg dry-YE diminished the lung tissue levels of eotaxin-1, eosinophil major basic protein and MUC5AC in OVA-exposed mice. Alcian blue/periodic acid schiff staining revealed that the dry-YE supplementation inhibited goblet cell hyperplasia and mucus overproduction in the trachea and bronchiolar airways of OVA-challenged mice. CONCLUSIONS: Oxidative stress may be involved in the induction of eotaxin-1 and MUC5AC by endotoxin episode and OVA challenge. Dry-YE effectively ameliorated oxidative stress-responsive epithelial eosinophilia and mucus-secreting goblet cell hyperplasia in cellular and murine models of asthma.