• 한국식품조리과학회지
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• 제32권6호
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• pp.762-772
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• 2016

Purpose: Adolescence is a critical period for growth and development; hence, knowledge about good food habits is essential amongst children. This study was conducted to investigate prevalence of awareness among food sellers, which could probably influence children's health and perceptions on food around schools towards adulterated food management beliefs, competencies, and food safety practices. Methods: Data was collected from 195 dealers around 25 elementary, middle and high schools in Daegu and Gyeongbuk provinces using a self-administered questionnaire in July and August, 2015. The data was analyzed using frequency analysis, one-way analysis of variance, $x^2$-test, factor analysis, and reliability analysis by SPSS Statistics (ver. 23.0). Results: A total of 121 people (62.1%) reported satisfaction of providing information and education on adulterated food. The perception of hazardous substances was found to be related to food poisoning bacteria and viruses (65.6%), heavy metals (42.1%), environmental hormones (36.4%), residual pesticides (27.2%), and irradiated food (26.7%). The perceived score on hygiene practices for processed food seller was $4.04{\pm}0.56/5.00$ and for cooked food seller was $4.09{\pm}0.45$. The capacity of adulterated food management practice of food sellers was significantly correlated with food knowledge on adulteration and public relation capacity, necessity of adulterated food management, and perception of hygiene practices (p<0.01). Similarly, knowledge and public relation capacity were significantly different according to ages (p<0.01). The perception of the necessity of adulterated food management was significantly different according to education levels (p<0.05), and the evaluation of hygiene practices was significantly different according to age (p<0.01). Conclusion: In order to solve the problem of adulterated food, which is one of the four social evils, and to strengthen the capacity of children to solve social problems, various practices like campaign on health promotion, goof food habits, education, and adulterated food management, should be actively promoted not only for children but also for food sellers around the schools.

• 한국산업보건학회지
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• 제30권2호
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• pp.87-98
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• 2020

Objective: The purpose of this study was to propose a sequential procedure for the simultaneous analysis of soluble and insoluble metal compounds. Methods: Methods for sampling and analyzing metal compounds such as ISO standards, NIOSH methods, HSE methods, and OSHA methods were reviewed. Results: Some metals have different OELs depending on the solubility of the compound. Therefore, we should take into account these characteristics and perform an exposure assessment. Soluble metal compounds are first extracted from the filter, and then the filter is digested by acids to analyze residual insoluble components. The extraction of soluble compounds can be completed by agitation for about 60 minutes with a leach solution (water) in a water bath at 37℃. For the analysis of insoluble compounds, the sample filter and the filtration filter remaining after the extraction of the soluble compounds are analyzed. This allows simultaneous determination of soluble and insoluble metal compounds. For hexavalent chromium compounds, soluble hexavalent chromium can first be extracted from the filter by using sulfate buffer. The insoluble hexavalent chromium remaining in the filter can then be extracted using carbonate buffer. Conclusion: Workers are often exposed to many hazardous substances with different exposure limits at industrial sites. The OELs for compounds of the same metal can be set differently depending on solubility. This study can help evaluate a worker's exposure to metal compounds by suggesting methods for the simultaneous determination of soluble and insoluble metal compounds.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권1호
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• pp.19-27
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• 2015

If $CO_2$ stored for geological sequestration escapes from deep formations and is introduced to shallow aquifers, it dissolves into groundwater, creates acidic environments, and enhance mineral dissolution from rocks and soils. Among these minerals, dissolution and spread of hazardous trace metals can cause environmental problems with detrimental impacts on groundwater quality. This study aims to investigate geochemical effects of $CO_2$ in groundwater on dissolution of galena, the main mineral controlling the mobility of lead. A series of batch experiments are performed with granulated galena in $CO_2$ solutions under various experimental conditions for $CO_2$ concentration and reaction temperature. Results show that dissolution of galena is significantly enhanced under acidic environments so that both of equilibrium concentrations and dissolution rates of lead increase. For thermodynamic analysis on galena dissolution, the apparent rate constants and the activation energy for galena dissolution are calculated by applying rate law to experimental results. The apparent rate constants are $6.71{\times}10^{-8}mol/l{\cdot}sec$ at $15^{\circ}C$, $1.77{\times}10^{-7}mol/l{\cdot}sec$ at $25^{\circ}C$, $3.97{\times}10^{-7}mol/l{\cdot}sec$ at $35^{\circ}C$ and the activation energy is 63.68 kJ/mol. The galena dissolution is suggested to be a chemically controlled surface reaction, and the rate determining step is the dissociation of Pb-S bond of surface complex.

• 한국식품과학회지
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• 제43권3호
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• pp.341-347
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• 2011

토종 복분자 딸기 열매를 이용하여 건강식품을 개발하기 위하여 성숙시기에 따라 토종 복분자 딸기 열매의 구성성분, 이화학적 특성과 항산화활성을 조사하였다. 숙성시기에 따라 미숙과, 중숙과 및 완숙과를 전남 곡성군에서 수확하여 동결건조하여 분말을 제조하고 분쇄과정에서 씨를 분리하여 비교하였다. 완숙된 토종복분자 딸기의 열매분말은 밝은 적색을 띠었으나 북미산 복분자 딸기 열매 분말은 칙칙한 검붉은색이었으며 토종 복분자 열매 씨는 북미산에 비해 더 부드럽고 작았다. 숙성시기에 따라 조단백질, 조지질과 총 당 함량은 증가하였고 회분과 총 식이섬유 함량은 감소하였다. 유리당은 fructose, glucose와 rhamnose가 분석되었는데 fructose가 가장 많았다. 아미노산은 aspartic acid와 glutamic acid를 많이 함유하고 있으며 필수아미노산 중에는 leucine함량이 높았다. 무기질 중 위해금속은 검출되지 않았고 성숙에 따라 감소경향을 보이며 K와 Ca함량이 높았다. 유기산도 성숙에 따라 감소하였으며 citric acid가 가장 많은 비율을 차지하였다. 총 페놀함량은 미숙과(12.84 mg/100 g)가 가장 높았고 중숙과와 완숙과(9.38, 9.66 mg/100 g)는 유사하였다. DPPH 자유라디칼 소거능으로 분석한 항산화활성은 86.21-81.22%로 미숙과가 높았고 성숙에 따라 감소하였다.

• 한국물환경학회지
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• 제22권1호
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• pp.23-29
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• 2006

Biosorption technology was used to remove hazardous materials from wastewater, herbicide, heavy metals, and radioactive compounds, based on binding capacities of various biological materials. Biosorption process can be explained by two steps; the first step is that target contaminants is in contact with microorganisms and the second is that the adsorbed target contaminants is infiltrated with inner cell through metabolically mediated or physico-chemical pathways of uptake. Until recently, no information is available to explain the definitive mechanism of biosorption. The purpose of this study is to evaluate biosorption capabilities of organic matters using activated sludge and to investigate affecting factors upon biosorption. Over 49% of organic matter could be removed by positive biosorption reaction under anoxic condition within 10 minutes. The biosorption capacities were constant at around 50 mg-COD/mg-MLSS for all batch experiments. As starvation time increased under aerobic or anaerobic conditions, biosorption capacity increased since higher stressed microorganisms by starvation was more brisk. Starvation stress of microorganisms was higher at aerobic condition than anaerobic one. As temperature increased or easily biodegradable carbon sources were used, biosorption capacities increased. Consequently, biosorption can be estimated by biological -adsorbed capability of the bacterial cell-wall and we can achieve the cost-effective and non -residual denitrification with applying biosorption to the bio-reduction of nitrate.

• 자원리싸이클링
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• 제7권3호
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• pp.27-35
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• 1998

전기로 제강업체에서 생성되는 분진을 매립할 경우 토양 및 수질오염등의 심각한 환경문제를 야기시킬 수 있지만 적절한 처리공정을 거치게 되면 고부가가치를 얻을 수 있는 Fe, Zn, Pb, Cd 등의 원소들이 함유되어 있다. 이에 국내외 제강업체에서는 폐자원의 재자원화 측면 뿐만 아니라 환경오염 억제 차원에서 이러한 전기로 분진중 유가금속의 회수를 위한 처리공정의 개발이 시급히 요구되고 있으나, 현재 전기로 분진의 대부분은 재활용 처리되지 않고 매립되고 있는 실정이다. 따라서, 본 연구에서는 전기로 분진에 함유된 산화철을 Fe로 회수하기 위한 기초자료를 얻고자 실제 전기로 분진의 화학적 조성과 유사한 시료를 제조하여 $1500^{\circ}C$ Ar 분위기 하에서 탄소첨가량 및 연기도의 변화가 슬래그내의 $Fe_2O$ 회수율에 미치는 영향을 조사하였으며 그 결과는 다음과 같다. 합성시료의 고온용융특성 조사에서 탄소환원당량 대비 탄소첨가량이 증가함에 따라 연화점 및 용융점이 증가하였으며 슬래그중 $Fe_2O$의 환원속도는 탄소환원당량대비 탄소첨가량이 100%, 염기도 1.7에서 가장 높았다. 또한 $Fe_2O$의 환원반응차수는 거의 1차반응임을 알 수 있었다.

• 한국토양비료학회지
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• 제37권6호
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• pp.396-406
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• 2004

Current physical and chemical methodologies, conventionally used to clean up metal contaminated soils, are generally too expensive to apply in large hazardous waste sites including agricultural lands adjacent to closed or abandoned metal mines. Phytoremediation using plants to extract, sequester and detoxify environmental pollutants is one of the cost-effective and aesthetically-pleasing alternatives, compared with environmentally destructive remedial methods currently being practiced. But, phytoremediation has some limitations such as time consuming and low performance: in general, it is seasonally dependent and slower in removing metals than other methods, and metal accumulating plants are slow growers. Improvement of plants for metal tolerance, accumulation, and translocation using genetic engineering techniques recently opened up new possibilities for phytoremediation. In this paper, we have discussed about recent developments in conventional and genetically engineered phytoremediation. For the conventional phytoremediation, focuses are on the natural hyperaccumulator and the chemically assisted phytoremediation. Some pros and cons on the phytoremediation using transgenic plants, coupled with focusing on the mechanistic view points, are also discussed. It might be concluded that the transgenic plants will be effective tools in the practical application of phytoremediation especially for the highly contaminated soils but mechanisms involved should be deeply understood in advance.

• 한국토양비료학회지
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• 제44권6호
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• pp.1085-1088
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• 2011

Heavy metal concentration as well as chemical composition were surveyed in commercial liquid pig manure to provide the basic information for mitigation research of hazardous material to agro-product. Seventy-five samples of liquid pig manure were collected and analyzed from 2009 to 2010 nationwide. Average contents of T-N, $P_2O_5$, and $K_2O$ were 0.29%, 0.08%, and 0.11%, respectively. The contents of heavy metals ranged from 0.001~0.083 for As, 0.001~0.108 for Cd, 0.002~0.495 for Cr, 0.07~47.8 for Cu, ND~0.005 for Hg, 0.035~1.033 for Ni, ND~0.291 for Pb, and $0.75{\sim}342.4mg\;L^{-1}$ for Zn, respectively. It was noted that among 75 samples, only four samples exceeded the Zn guideline ($130mg\;L^{-1}$) of liquid fertilizer derived from livestock manure but others were not exceeded the regulation.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.73-81
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• 2018

The giant mealworm beetle, Zophobas atratus (Coleoptera: Tenebrionidae), is a tropical beetle. As this beetle can be used as an ingredient in animal feed, the effects of brewer's spent grain (BSG) on the development and nutritional value of Z. atratus were investigated. As results, there were no significant differences on the larval survival rate, body weight, and duration at different content of BSG, mixed with conventional feed, wheat bran (WB). Based on these results, BSG can be mixed with wheat bran as a Z. atratus food ingredient without any problems. The nutritional value was compared between 100% wheat bran control and 50% BSG experimental groups. The moisture, crude protein, carbohydrates, and amino acids were 1.1-1.4 times higher in the 50% BSG group. In the BSG group, the linoleic acid content was 1.6 times higher than that in the control group. In the wheat bran group, the oleic acid content was 38.4%, which was 1.3 times higher than that in the BSG group. As minerals, the control and BSG groups showed high potassium and phosphorus contents. In terms of hazardous materials, four heavy metals (lead, mercury, arsenic, and cadmium) and two microorganisms (Escherichia coli and Salmonella spp.) were not detected. There were no significant differences in developmental characteristics between the wheat bran and BSG mixed groups, and the nutritional values were better in the BSG mixed group. Therefore, BSG can be used as alternative food source for rearing Z. atratus.

• 융합정보논문지
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• 제10권12호
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• pp.208-215
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• 2020

본 연구는 SUKI를 활용하여 두피의 중금속 감소에 대해 미치는 영향에 대해 알아보았다. 연구대상자는 총 26명이었으며 실험군과 대조군 각각 13명이었다. SUKI 도구를 활용한 두피 중금속 배출에 대한 중재를 8주간 주 2회씩 실시하였고, 결과는 다음과 같다. 총 각각 8 종목의 실험군과 대조군의 비교에서 실험군에서 유의한 차이가 있었다. 실험군의 중금속인 Hg, Pb, Al, Cd, As, Ba, Ur, Cs 중에서 6가지 항목의 Hg, Al, Cd, As, Ba, Ur과 같은 중금속들에서 통계적으로 유의한 감소(p<.05)를 보여주었으며, Pb, Cs 는 유의하지 않았다. 그리고 해당 유해중금속 중에서 Al, Ba, Hg가 가장 큰 차이의 감소율을 나타냈다. 따라서 SUKI 도구의 중재가 일부 중금속 배출에 영향을 줄 수 있다는 것을 시사한다(p<.05). 결론적으로 향후 지속적인 연구를 통해 두피의 중금속 배출을 위한 기초자료로 활용될 수 있을 것으로 사료된다.