• 한국산업보건학회지
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• 제10권1호
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• pp.45-57
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• 2000

Results of environmental monitoring for 35 steel industry welders exposed to manganese and chromium fume were evaluated. Efficiency of respiratory protectors, welding face shields and local exhaust ventilation were also evaluated to establish more efficient preventive measures that can protect welders from occupational disease as related to welding fume. The results are as follows; 1. Total fume from $CO_2$ arc welding with mild steel occurred 1.5 to 2.2 times more than that from shielded metal arc welding. Chromium and nickel fume from welding with stainless steel occurred 27 to 59 times and 18 to 30 times, respectively, than those with mild steel. 2. Proportions of water-soluble chromium(VI) and insoluble chromium(VI) Compare to total chromium occurring from $CO_2$ arc welding with stainless steel were 10.5% and 8.7%, respectively, while those with mild steel were 57.1 to 63.2% and 31.6 to 38.1%, respectively. 3. The efficiencies of 4 types of respiratory protectors to reduce welding fume exposure were evaluated as 54.4 to 64.4%. 4. The reducing effect of head type welding face shield was 67.6%, and that of hand type welding face shield was 58.5%. The highest reducing effect was shown in air supply welding face shield as 99.2%, although it is not convenient to wear. 5. When welding face shield and respiratory protectors were worn together, the reducing efficiency increased to 79.0 to 87.5%. 6. When local exhaust ventilation was installed in workplace, the reducing efficiencies varied from 31.5 to 73.1% according to the types of welding.

• 상하수도학회지
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• 제32권2호
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• pp.145-152
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• 2018

This study is focused on manganese (Mn(II)) removal by ozonation in surface water. Instant ozone demand for the water was 0.5 mg/L in the study. When 0.5 mg/L of Mn(II) is existed in water, the optimum ozone concentration was 1.25 mg/L with reaction time 10 minutes to meet the drinking water regulation. The ozone concentration to meet the drinking water regulation was much higher than the stoichiometric concentration. The reaction of soluble manganese removal was so fast that the reaction time does not affect the removal dramatically. When Mn(II) is existed with Fe, the removal of Mn(II) was not affected by Fe ion. However As(V) is existed as co-ion the removal of Mn(II) was decreased by 10%. Adding ozone to surface water has limited effect to remove dissolved organic matter. When ozone is used as oxidant to remove Mn(II) in the water, the existing co-ion should be evaluated to determine optimum concentration.

• 수도
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• 통권32호
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• pp.1-10
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• 1984

• Journal of Nutrition and Health
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• 제39권5호
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• pp.485-493
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• 2006

The purpose of this study was to investigate the relationships among nutrient intakes, BMD, serum copper, zinc and manganese contents in Korean postmenopausal women residing in Seoul and Kyunggi-do. Nutrient intakes analyses and anthropometric measurements were performed for 64 postmenopausal women. Also, fasting blood samples were collected. The BMDs of the lumbar spine (L2-L4) and femoral neck were measured by dual energy X-ray absorptiometry (DEXA). Subjects were classified into three groups: osteoporosis (T-score ${\leq}$ -2.5, n = 20), osteopenia (-2.5 < T-score ${\leq}$ -1, n = 24), and normal (T-score) -1, n = 20). The results are summarized as follows; the mean age, height and weight were 62.1 yrs, 153.8 em, and 56.1 kg, respectively, with no significant difference among three groups. On the other hand, the mean BMI $(23.7\;g/m^2)$ of normal group was significantly higher than those of other two groups. The mean energy intake was 1,395.3 kcal (77.5% of Dietary referance intakes for koreans (KDRls)). The average daily intakes of vitamin $B_2$, calcium and zinc did not reach KDRIs. The mean intakes of iron, copper, zinc and manganese were 10.9 mg, 1.6 mg, 7.8 mg and 5.1 mg respectively, with no significant difference among three groups, The mean serum levels of copper, zinc and manganese were 96.4 mg/dl, 91.5 mg/dl and 39.5 ng/dl, respectively with no significant differences among three groups. The BMD of lumbar spine showed a significantly negative correlation intakes of animal protein, fat and iron intakes after adjusting for age, Bill. However, the BMD of lumbar spine was not significantly correlated with animal iron intakes after adjusting for animal protein, and fat intakes, indicating animal food intake is a possible confounding factor. Proper intakes of vitamin $B_2$, vitamin C are required to protect osteoporosis in postmenopausal women. These results suggest that excessive animal food intakes may have adverse effect on bone mineral density. Further studies arc necessary to elucidate the role of serum minerals in BMD.

• Asian Pacific Journal of Cancer Prevention
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• 제13권9호
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• pp.4249-4253
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• 2012

While associations between trace elements and heavy metals with prostate cancer are still debatable, they have been considered as risk factors for prostate cancer. Thus, this study aimed to detect any links between selected minerals and heavy metals including Se, Zn, Cu, Mn and Fe with prostate cancer. A case control study was carried out among 100 subjects (case n=50, control n=50), matched for age and ethnicity. Trace elements and heavy metals level in hair and nail samples were determined by ICP-MS. Mean selenium levels in hair and nail of the cases were significantly lower as compared to controls. A similar trend was noted for zinc in both hair and nail samples, whereas the mean level of copper was significantly higher in cases than controls. Similar elevation was noted for iron and manganese (p<0.05 for all parameters). Low levels of selenium and zinc and high levels of copper, iron and manganese appear to be associated with the risk of prostate cancer. Further studies to elucidate the causal mechanisms and appropriate chemopreventive measures are needed.

• 한국식품위생안전성학회지
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• 제9권4호
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• pp.229-235
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• 1994

It is very important to investigate the sanitary chemical conditions of farmwaters used for cattle breeding in the dairy farms. For this purpose we examined pH, KMnO4 consumption, total hardness, chloride, sulfate, NH3-N, NO3-N, fluoride, lead, iron, manganese, cadmium, copper, zinc and chrome in the farmwaters sampled 2 times(spring and summer)in Choongcheongnam and Kangwon Province. The pH of farmwaters in Choongcheongnam and Kangwon Province was 6.49$\pm$0.09, 6.70$\pm$0.06, total hardness 90.21$\pm$7.07, 64.53$\pm$6.38 mg/ι, consumption of KMnO4 4.13$\pm$0.62, 4.34$\pm$0.26mg/ι, NO3-N 6.51$\pm$0.55, 3.61$\pm$0.58 mg/ι, chloride ion 20.51$\pm$1.99, 5.41$\pm$1.36 mg/ι and sulfate ion 6.61$\pm$1.02, 7.28$\pm$1.30 mg/ι, respectively. But NH3-N was scarcely detected. Fluoride, iron, lead, cadmium, zinc, manganese and chrome were not detected from the tested farmwaters. There was high significance between each other in total hardness, NO3-N, chloride ion and sulfate ion. There was regional and seasonal significance in only NO3-N but only regional significance in total hardness and chloride ion.

• 생약학회지
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• 제16권4호
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• pp.181-190
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• 1985

To determine contents of inorganic elements of Ganoderma lucidum, the horn-shaped carpophores and the pileus of Ganoderma lucidum were incinerated and analyzed by inductively coupled plasma atomic emission spectrophotometry. The ash contents of the pileus and the horn-shaped carpophore were 1.48% and 1.40%, respectively. The pileus contained calcium, magnesium, sodium, manganese, iron, zinc and germanium in that order. The horn-shaped carpophore contained magnesium, calcium, zinc, manganese, iron, copper and germanium in that order. To examine the protein-bound polysaccharide from Ganoderma lucidum for immunopotentiating activity, its fruit bodies were extracted with hot water. Purification of the extract was carried out by acetone precipitation and dialysis. The fraction obtained during the purification procedure consisted of a polysaccharide moiety (51%) and a protein moiety (5%). When the compound was administered intraperitoneally to the mice at a dose of 50mg/kg, it enhanced the accumulation of the peritoneal exudate cells, macrophage and polymorphonuclear leucocytes, thereby indicating immunopotentiation.

• 한국재료학회지
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• 제18권6호
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• pp.298-301
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• 2008

A preparation of $Ni_xMn_{1-x}Fe_2O_4$ nanoparticles produced via the reduction of Nickel nitrate hexahydrate, Manganese (II) nitrate hexahydrate and Iron nitrate nonahydrate with hydrazine in Igepal CO-520/cyclohexane reverse micelle solutions was investigated. Transmission Electron Microscope (TEM), X-ray Diffraction (XRD) and Vibration Sample Magnetometer (VSM) analyses showed that the resultant nanoparticles increased the molar ration of water to Igepal CO-520 as the concentrations of Nickel nitrate hexahyrate, Manganese (II) nitrate hexahydrate and Iron nitrate nonahydrate increased. The average size of the synthesized particles calcined at $600^{\circ}C$ for 2hrs was in the range of 20 nm to 30 nm, and the particle distribution was broadened. The phase of the synthesized particles was crystalline, and the magnetic behavior of the synthesized particles was superparamagnetism. The effect of the synthesis parameters of the molar ratio of water to surfactant and the calcination temperature was discussed.

• 한국균학회지
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• 제13권1호
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• pp.53-55
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• 1985

한국(韓國)에서 인공재배( 人工栽培)한 영지(靈芝)의 회분(灰分)은 갓과 녹각지가 각각 1.48%와 1.40% 였으며, 무기(無機) 성분(成分)은 갓부분에서는 Ca이 가장 많이 함유(含有)되어 있었으며, 그 다음은 Mg, Na, Mn, Fe, Zn, Cu, Ge의 순서로 함유(含有)되어 있었다. 녹각지에서는 Mg이 가장 많이 함유(含有)되어 있었으며, 그 다음은 Ca, Na, Zn, Mn, Fe, Cu, Ge의 순시로 함유(含有)되어 있었다.

• Advances in nano research
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• 제4권1호
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• pp.1-14
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• 2016

Superparamagnetic iron oxide nanoparticles (Nps), composed of magnetite, $Fe_3O_4$, or maghemite, ${\gamma}-Fe_2O_3$, core and biocompatible polymer shell, such as dextran or chitozan, have recently found wide applications in magnetic resonance imaging, contrast enhancement and hyperthermia therapy. For different diagnostic and therapeutic applications, current attempt is focusing on the synthesis and biomedical applications of various ferrite Nps, such as $CoFe_2O_4$ and $MnFe_2O_4$, differing from iron oxide Nps in charge, surface chemistry and magnetic properties. This study is focused on the synthesis of manganese ferrite, $MnFe_2O_4$, Nps by most commonly used chemical way pursuing better control of their size, purity and magnetic properties. Co-precipitation syntheses were performed using aqueous alkaline solutions of Mn(II) and Fe(III) salts and NaOH within a wide pH range using various hydrothermal treatment regimes. Different additives, such as citric acid, cysteine, glicine, polyetylene glycol, triethanolamine, chitosan, etc., were tested on purpose to obtain good yield of pure phase and monodispersed Nps with average size of ${\leq}20nm$. Transmission electron microscopy (TEM), X-ray diffraction, energy dispersive X-ray spectroscopy (EDX), $M\ddot{o}ssbauer$ spectroscopy down to cryogenic temperatures, magnetic measurements and inductively coupled plasma mass spectrometry were employed in this study.