• Asian-Australasian Journal of Animal Sciences
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• 제17권12호
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• pp.1695-1699
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• 2004

The antioxidant enzymes, lipid peroxidation and free radicals assessment were made of the effects of selenium, copper and magnesium on bovine endemic fluorosis under high fluoride, low selenium and low copper productive conditions. Thirty-two beef cattle were selected from high fluoride area, and randomly divided into four groups with eight cattle each as follows: (1) high fluoride control group (HFC); (2) supplemented group with 0.25 mg/kg selenium (HFSe); (3) supplemented group with 15 mg/kg copper (HFCu) and (4) supplemented group with 0.25 mg/kg selenium+15 mg/kg copper+1 mg/kg magnesium (HFSeCuMg) per day for 83 days. Moreover, eight beef cattle were selected from non-high fluoride area as normal control group. Blood samples were collected from cattle on 0 d, 30 d and 83 d respectively, to analyze the enzyme activities and concentration of GSH-px, CAT, SOD, MDA and free radicals. The results showed that the contents of free radicals and MDA in HFC group were significantly higher, and the whole blood GSH-px, CAT, erythrocyte SOD activities were lower than the normal control group. Free radicals, metabolic imbalance and antioxidant disorder therefore, play an important role in fluorosis. However, GSH-px, CAT and SOD activities in HFSe group and HFSeCuMg group at 30 d and 83 d were markedly higher than the same groups at the 0 d and the HFC group at the same time. Likewise, there was a corresponding reduction in the contents of free radicals and MDA. These findings indicated that supplementation with selenium, copper and magnesium elevated high fluoride bovine antioxidant enzymes, and decreased MDA and free radicals contents. But, the activities of supplementation selenium group did not increase until day 83. These results demonstrated that fluorosis was associated with lower serum Se and Cu levels than in the control, and it was therefore concluded that fluorosis is associated with decreased serum levels of these minerals. Long-term high fluoride intake under productive condition enhances oxidative stress in the blood, thereby disturbing the antioxidant defense of cattle. Increased oxidative stress could be one of the mediating factors in the pathogenesis of toxic manifestations of fluoride. It is benefical for high fluoride cattle supplemented with proper selenium, copper and magnesium to increase fluoride excretion and obtain the protective impact of the activity of oxidative enzymes, and to decrease lipid peroxidation and free radicals contents.

• Safety and Health at Work
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• 제15권1호
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• pp.114-117
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• 2024

A lithium-ion battery is a rechargeable battery that uses the reversible reduction of lithium ions to store energy and is the predominant battery type in many industrial and consumer electronics. The lithium-ion batteries are essential to ensure they operate safely. We conducted an exposure assessment five days after a fire in a battery-testing facility. We assessed some of the potentially hazardous materials after a lithium-ion battery fire.We sampled total suspended particles, hydrogen fluoride, and lithium with real-time monitoring of particulate matter (PM) 1, 2.5, and 10 micrometers (㎛). The area sampling results indicated that primary potential hazardous materials such as dust, hydrogen fluoride, and lithium were below the recommended limits suggested by the Korean Ministry of Labor and the American Conference of Governmental Industrial Hygienists Threshold Limit Values. Based on our assessment, workers were allowed to return to work.

• 한국토양비료학회지
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• 제14권3호
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• pp.157-162
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• 1981

농작물(農作物)에 대(對)한 불화수소(弗化水素)가스의 피해(被害)를 경감(輕減)시키기 위(爲)하여 피해경감제(被害輕減制)로서 소석회(消石灰) 규회석(硅灰石), 인산질(燐酸質)을 토양(土壤)에 시용(施用)하여 수도(水稻)를 재배(裁培)하고 $0.1g/m^3$의 불화수소(弗化水素)가스를 1시간(時間)씩 접촉(接觸)한후(后) 수량감소정도(收量減少程度), 피해엽율(被害葉率), 식물체중(植物體中)의 불소함량(弗素含量) 및 규산함량(珪酸含量)을 조사(調査)한 결과(結果)는 다음과 같다. 1. 불화수소(弗化水素)가스 피해경감효과(被害輕減效果)는 소석회(消石灰) 및 규회석(硅灰石)이 가장 좋았다. 2. 불화수소(弗化水素)가스를 접촉(接觸)하지 않은 구(區)에서는 개량제처리간(改良劑處理間)에 수량착이(收量着異)가 없었으나 불화수소(弗化水素)가스를 접촉(接觸)하므로서 개량제간(改良劑間)에 유의성(有意性) 있는 수량 수량착이(收量着異)가 있었다. 3. 식물체내(植物體內) 불소함량(弗素含量)은 감수율(減收率) 및 피해엽율(被害葉率)과 각각(各各) 정(正)의 상관(相關)이 있었다.

• 자원리싸이클링
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• 제16권3호
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• pp.12-18
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• 2007

수산물 처리과정중에서 다량으로 발생하는 폐굴껍질을 흡착제로 활용하는 방안을 모색하고자 이의 물성을 분석하였다. 폐기되는 굴껍질의 조성은 대부분 $CaCO_3$인 것으로 나타났으며 온도를 증가시키면서 굴껍질을 열분해를 시키면 온도에 따라 수분과 $CO_2$에 의한 분해가 일어나 약 46%의 무게 감량을 보인다. pH가 증가할수록 흡착되는 불소 이온의 양은 크게 감소했다. 또한 산성 불소 폐수가 흡착 반응의 평형에 도달하였을 경우 굴껍질에서 용해된 ${CO_2}^{3-}$의해 중화되는 경향이 관찰되었다.

• 한국토양비료학회지
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• 제14권3호
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• pp.163-168
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• 1981

농작물(農作物)에 대(對)한 불화수소(弗化水素)가스의 피해(被害)를 경감(輕減)시키기 위(爲)하여 피해경감제(被害輕減劑)로서 소석회(消石灰) 규회석(硅灰石)을 토양(土壤)에 증시(增施)하여 수도(水稻)를 재배(裁培)하고 $0.05g/m^3$ 및 $0.10g/m^3$의 불화수소(弗化水素)가스를 1시간(時間)씩 접촉(接觸)한후(后) 수량감소정도(收量減少程度), 피해엽율(被害葉率), 식물체중(植物體中)의 불소함량(弗素含量) 및 규산함량(珪酸含量)을 조사(調査)한 결과(結果)는 다음과 같다. 1. 소석회(消石灰) 및 규회석시용량(硅灰石施用量)에 따른 불화수소(弗化水素)가스에 의(依)한 피해경감효과(被害輕減效果)는 석회(石灰) 중화량(中和量)+150kg/10a이 가장 좋았고, 규회석(硅灰石)은 150kg/10a 시용(施用)이 가장 효과(效果)가 좋았다. 2. 식물체중(植物體中) 불소함량(弗素含量)과 피해엽율(被害葉率)이 증가(增加)함에 따라 피해(被害)가 증가(增加)되었다. 3. 가스접촉(接觸) 식물체중(植物體中) 불소함량(弗素含量)이 많았던 구(區)에서 수확기(收穫期) 식물체중(植物體中) 규산함량(珪酸含量)이 많았다. 4. 시용량(施用量) 증가(增加)에 따라서 토양중(土壤中) 가용성(可溶性) 규산함량(珪酸含量)이 增加하였고 식물체중(植物體中) 규산함량(珪酸含量)도 증가(增加)하는 경향(傾向)이었다.

• 치위생과학회지
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• 제10권4호
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• pp.295-300
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• 2010

본 연구에서는 자가 미백제로 많이 사용되고 있는 10% CP를 이용하여, 불소가 함유되지 않은 미백제, 불소가 함유된 미백제, 그리고 10% CP로 미백한 후에 불소를 적용하여 하루에 8시간씩 14일 동안 처리함으로써, 치아표면의 색과 미세경도에 미치는 영향을 평가하여 다음과 같은 결론을 얻었다. 1. 색조 변화측정 결과, 대조군을 제외하고 미백 처리한 모든 군에서 치아 미백 후 시간 경과에 따라 $L^*$ 값과 ${\Delta}E^*$ 값에 유의한 차이가 있었고(p<0.05), 비슷한 수준의 미백효과와 함께 치아의 색조에서 노란색이 감소됨을 관찰할 수 있었다. 2. 미백 처리 전후의 법랑질의 표면경도를 분석한 결과 대조군에서는 별 차이를 보이지 않았으나, 미백 처리한 모든 군에서 유의한 미세경도 감소를 보였다(p<0.05). 특히 10% CP군은 가장 낮은 미세경도 수치를 보였고, 미백제에 불소가 함유된 군과 미백 후 불소를 적용한 군은 미세경도 감소폭이 줄어들었다. 이상의 결과를 종합해 보면, 2주간 진행되는 10% CP는 치아미백에 효과적이며, 미백제에 불소를 함유시켜도 미백에는 영향을 주지 않았으며, 표면미세경도는 불소가 함유되지 않은 미백제에 비해 덜 감소했다. 임상에서 미백으로 인한 부작용을 최소화하는데 적정 농도의 불소를 이용해 적용될 수 있도록 더 많은 연구가 이루어져야 할 것으로 사료된다.

• 한국대기환경학회지
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• 제2권1호
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• pp.11-21
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• 1986

The study was performed to investigate the effects of gaseous imission of sulfur dioxide and hydrogen fluoride on the growth of rice plant under stressed field conditions. The plants were cultivated in normal paddy fields where are 88 industrial plants operating with 285 smoke stacks emitting pollutants. There has been a number of reported studies (1, 3, 11, 19, 20) which deal with rice plant damages by air pollution under a simulated exposure experimental condition. Furthermore, these experiments were conducted to examine effects of a single pollutant on the plant. Furthermore, these experiments were conducted to examine effects of a single pollutant on the plant. In korea, however, there is no study reported in literature with respect to the in-situ dose-response relationship between rice pant reduction in yields and air pollution. This study is specifically dealt with multiple effects of sulfur dioxde and hydrogen fluoride on various plant growth indicators such as leaf damage, culm height, weight of grain, panicles per hill, spikelets per panicle and percent fertility.It appears that there is a good correlation between ambient concentrations of sulfur oxides and sulfur contents found in leaves with an average correlation coefficient of 0.868 within a 1% significance level. It is interesting to note that a better multiple correlation was found between percent leaf damage and sulfur and fluoride contentd found in leaf with a significance of 1% level. The yearly correlation coefficient ranges from 0.963 to 0.987 with an average being 0.971. It is, therefore, believed that a percent leaf damage may serve as a single indicator of pollutional damages to rice plant cultivating in fields. Regarding other factors to the diminution of rice plant growth in polluted atmosphere, it appears that a significant correlation to culm length and dry weight of grain with a 1% significance level whereas T/R ratio has a good correlation with lead damage within 5% significance level. An evaluation of data observed has demonstrated that both panicles per hill and percent fertility are significantly affected by air pollutants. As expected, hydrogen fluoride has more effects than sulfur oxide. It is, however, interesting to note that spikelets per panicles has slightly been affected while no indication of effects on 1000-grain-weight has been observed. This may lead to a conclusion that a reduction in yield of rice under polluted field conditions may have more been caused by the diminution of panicles per hill and percent fertility rather than by the diminution of spikelets per panicle and grain weight.

• 대한치과교정학회지
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• 제30권6호
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• pp.723-730
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• 2000

교정적인 치아이동은 치주조직, 특히 치조골의 개조를 필요로 한다. 불소는 파골세포에 의한 골흡수를 방해하는 물질로 알려져 있다. 이 연구의 목적은 불소의 섭취가 교정적인 치아이동시 압박측 치주조직에서 파골세포의 출현에 어떠한 영향을 끼치는 지를 조사하는 것이다. 40마리의 백서에게 60일동안 불화나트륨(NaF)가 각각 0, 10, 25 mg/kg/일 함유된 물을 음수시킨 후, 약 50-70g의 교정력을 가하여 상악 제 1 대구치를 근심쪽으로 경사이동시켰다. 교정력을 가한 24, 48, 그리고 96 시간 후에 대조군과 실험군을 희생시킨 후 조직편을 제작하여 상악 제 1 대구치의 압박측 치주조직 $450\times700\;{\mu}m^2$을 관찰하여 출현한 파골세포의 수와 흡수량을 조사하여 다음과 같은 결론을 내렸다. 1. 모든 측정시간에서 25 mg/kg/일 군에서 대조군보다 파골세포의 수가 유의성 있게 적었다. (p<0.05) 2. 24, 48시간 측정에서 25 mg/kg/일 군에서 대조군보다 흡수되는 면적이 유의성 있게 적었다. (p<0.05) 3. 대조군에서는 48시간에서 96시간 사이에 흡수되는 면적이 약간 감소하였으나, 10 mg/kg/일 군과 25 mg/kg/일 군 모두에서는 약간 증가하였다.

• Macromolecular Research
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• 제11권1호
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• pp.9-13
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• 2003

Poly (vinylidene fluoride) (PVDF) samples were implanted by using high energy (MeV)F$^{2+}$ and Cl$^{2+}$ ions. We observed that AC dielectric constant of the ion-implanted PVDF samples decreased from 10.5 to 2.5 at 1 kHz as the ion dosage increased from 10$^{11}$ to 3 $\times$ 10$^{14}$ ions/$\textrm{cm}^2$. From differential scanning calorimetry experiments, we observed that PVDF samples become more disordered state through the ion implantation. The decrease of the number of bonding of C-H and C-F and the increase of unsaturated bonding were observed from X-ray photoelectron spectroscopy experiments. The emission of HF and H$_2$ molecules during the ion implantation was detected by residual gas analyzer spectrum. Based upon the results, we analyzed that the low AC dielectric constant of the MeV ion-implanted PVDF samples originated from the reduction of polarization due to the structural change of the CF$_2$ molecules in the MeV ion-implanted PVDF samples.les.

• 대한치과교정학회지
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• 제24권1호
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• pp.181-192
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• 1994

The effect of topical application on the number of S. mutans was tested in a group of 44 orthodontic patients (mean age, 12Y 3M). They were divided into 5 groups according to the method using NaF and $SnF_2$. The number of S. mutans CFU were counted in stimulated saliva of each subject at baseline, and after one, two, three, and eight weeks. The following results were obtained. 1. In NaF rinsing group, and NaF topical application and NaF rinsing group, the number of S. mutans per ml saliva was not significantly changed. 2. In $SnF_2$ topical application group, and $SnF_2$ topical and NaF rinsing group, the number of S. mutans per ml saliva was significantly reduced. 3. After 8 weeks, there were no significant reduction of the number of S. mutans in comparison with baseline.