• 제목/요약/키워드: low-mass

검색결과 4,473건 처리시간 0.034초

어린이와 학부모의 식품첨가물에 대한 인식 및 정보요구도 추이 분석: 2008~2013 식품첨가물 섭취 안전성 평가 연구 결과를 중심으로 (Trends of Perception and Information Needs on Food Additives of Children and Parents by Analyzing the Safety Assessment Reports of Food Additives in 2008~2013)

  • 김선아;김지선;고정미;김정원
    • 한국식품조리과학회지
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    • 제30권3호
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    • pp.249-261
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    • 2014
  • This study was performed in order to grasp the trends of elementary school children and their parents on their purchasing behavior of processed foods, awareness of food additives and its education experience by analyzing the safety assessment reports of food additives in 2008~2013. The most important factor in purchasing processed foods was safety in both groups followed by nutrition in parents and taste in children, respectively. While purchasing foods, the first item that is checked has been shifted from food additives to the origin of the products. Parents still perceived food additives as the most hazardous factor for food safety; however, recently, children began to regard microbial contaminants as being most hazardous, which is regarded as a desirable educational effect. The most concerned food additives were preservatives, synthetic seasoning and colorants in both groups. However, the awareness level on food additives still remained low as 3.0~3.1/5.0 for parents and 2.4~2.9/5.0 for children. Educational experience on food additives increased in children from 12% in 2008 to 25% in 2013; however, it decreased in parents from 23% in 2008 to 15% in 2013. Information needs for food additives by education and promotion were very high both in parents (4.2~4.5) and children (3.8~4.1). Both groups had an interest in the safety, legal standards of food additives, and foods with food additives, in order. The most reliable resource institutions on food additives were university/research institute and hospital for parents, but, hospital and government for children. The preferred media on food additives were TV and the internet for parents, and school newsletter and TV for children. Overall, the above results demonstrated that the perceptions on food additives did not change much with parents during the last 6 years; however, children's perceptions began to show improvement with the increase of educational experience. Hence, the government needs to make efforts to increase the trust level of consumers by developing educational tools and providing educational experiences including mass media for the promotion of risk communication on food additives.

원주 귀래2리 가마터 출토 백자의 화학조성과 소성온도 연구 (A Study on Chemical Composition and Firing Temperature of White Wares from the Guyre-2ri Kiln Sites, Wonju)

  • 이병훈;소명기
    • 보존과학회지
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    • 제30권3호
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    • pp.249-261
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    • 2014
  • 본 연구에서는 강원도 원주 지역에서 발굴된 귀래2리 1호 가마터와 2호 가마터에서 출토된 백자의 제작 기술 및 사용 원료의 특징을 살펴보고 출토 백자 원료의 연관성을 도출하고자 하였다. X-선 형광분석기(XRF)와 X-선 회절분석(XRD), 열팽창계수 측정(Dilatometer), 유도결합 플라즈마 질량 분석법(ICP-MS) 및 유도결합 플라스마 방출 분광법(ICP-AES)을 이용하여 대상 시편에 대해서 각각 화학 조성과 결정상, 소성온도, 미량원소 및 희토류원소 등을 분석하였다. 귀래2리 가마터 출토 백자는 착색 산화물과 융제의 함유량이 높은 특징을 나타낸다. 소성온도는 시편마다 차이가 있지만 대부분 $1200^{\circ}C$ 이하에서 소성 되었으며 일부 시편은 $1000^{\circ}C{\pm}20^{\circ}C$에서 저온 소성되었고 귀래2리 1호 가마터 출토 백자 중 일부는 $1200^{\circ}C$ 이상 고온에서 소성되었다. 분석 대상 백자의 태토를 XRD 분석한 결과 모두 quartz와 mullite가 검출 되었으며 quartz와 mullite의 검출 비율은 모두 비슷하다. 출토된 백자 태토의 제겔식을 이용한 분석 결과 대상 백자 모두 같은 영역에서 군집하여 태토 원료와 제작 기법의 유사성을 확인할 수 있다. 또한 희토류 원소 분석 결과를 통하여 분석 대상 백자는 지질학적 성인이 동일한 모암으로 제작했음을 알 수 있다.

Evaluation of Residual Pesticides in Fresh Ginseng Collected in Seoul

  • Kim, Tae-Rang;Park, Ki-Hwan;Jang, Mi-Ra;Choi, Young-Hee;Kim, Eun-Hee;Choi, Chae-Man;Park, Sung-Kyu;Yu, In-Sil;Hwang, In-Sook;Han, Ki-Young;Kim, Moo-Sang;Kim, Jung-Hun;Chae, Young-Zoo
    • Journal of Applied Biological Chemistry
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    • 제56권1호
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    • pp.29-35
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    • 2013
  • This study was performed to analyze 48 kinds of pesticide residues using gas chromatography (GC)/nitrogen phosphorous detector, GC/micro electron capture detector, GC/mass selective detector, and high performance liquid chromatograph/diode array detector in 186 fresh ginseng samples collected in the Seoul area from 2010 to 2011. Fresh ginseng dietary intakes were estimated using the data from the 2009 Korea National Health and Nutrition examination survey. Residual pesticides were detected in 79 samples (42.5%) with eight different fungicides. Only 20 samples (10.8%) exceeded the maximum residue limits (MRLs) for pesticides registered by the Korea Food & Drug Administration. Among them, tolclofos-methyl residues (10.2%) exceeded the MRL for fresh ginseng in 18 ginseng seedlings and one of the two-year old fresh ginseng plants, and the residual level in just one ginseng seedling violated the MRL for pyrimethanil. The results showed that residual pesticides levels in marketable fresh ginseng around Seoul were relatively safe. The percent acceptable daily intake (%ADI) was calculated using pesticide residues in fresh ginseng and dietary intakes of fresh ginseng. The risk caused by pesticide residues in fresh ginseng was very low.

Purification and Characterization of a Thermostable Xylanase from Paenibacillus sp. NF1 and its Application in Xylooligosaccharides Production

  • Zheng, Hong-Chen;Sun, Ming-Zhe;Meng, Ling-Cai;Pei, Hai-Sheng;Zhang, Xiu-Qing;Yan, Zheng;Zeng, Wen-Hui;Zhang, Jing-Sheng;Hu, Jin-Rong;Lu, Fu-Ping;Sun, Jun-She
    • Journal of Microbiology and Biotechnology
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    • 제24권4호
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    • pp.489-496
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    • 2014
  • High levels of extracellular xylanase activity (211.79 IU/mg) produced by Paenibacillus sp. NF1 were detected when it was submerged-cultured. After three consecutive purification steps using Octyl-Sepharose, Sephadex G75, and Q-Sepharose columns, a thermostable xylanase (XynNF) was purified to homogeneity and showed a molecular mass of 37 kDa according to SDS-PAGE. The specific activity of the purified XynNF was up to 3,081.05 IU/mg with a 14.55-fold purification. The activity of XynNF was stimulated by $Ca^{2+}$, $Ba^{2+}$, DTT, and ${\beta}$-mercaptoethanol, but was inhibited by $Fe^{2+}$, $Zn^{2+}$, $Fe^{2+}$, $Cu^{2+}$, SDS, and EDTA. The purified XynNF displayed a greater affinity for oat spelt xylan with the maximal enzymatic activity at $60^{\circ}C$ and pH 6.0. XynNF, which was shown to be cellulose-free, with high stability at high temperature ($70^{\circ}C-80^{\circ}C$) and low pH range (pH 4.0-7.0), is potentially valuable for various industrial applications. The enzyme hydrolyzed oat spelt xylan to yield mainly xylooligosaccharides (95.8%) of 2-4 degree of polymerization (DP2-4). Moreover, the majority of the xylooligosacharides (DP2-4) products was xylobiose (61.5%). The thermostable xylanase (XynNF) thus seems potentially usefull in the production of xylooligosaccharides.

혐기-무산소-호기 반응조내 질화세균군의 변화 (Changes of Nitrifying Bacterial Populations in Anaerobic-Anoxic-Oxic Reactors)

  • 박종웅;이영옥;고준혁;라원식;임욱민;박지은
    • 대한환경공학회지
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    • 제27권2호
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    • pp.138-144
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    • 2005
  • 본 연구는 질화작용에 관여하는 Nitrosomonas sp. 등의 암모니아산화세균과 Nitrobacter sp. 등 아질산산화세균이 $A^2/O$ Pilot 장치의 혐기조, 무산소조, 호기조에서 어떤 양상으로 변화하는지를 조사하는데 있다. 혼합액의 부유 질화세균군과 폐타이어로 성형 제조된 입상담체에 부착된 질화세균군은 FISH법으로 분석하였다. Pilot 장치의 질산화속도는 $1.97{\sim}2.98mg\;N/g\;MLVSS{\cdot}hr$의 값을 보였다. 각 반응조에서 총 부유 세균수중 암모니아 산화세균군 (NSO로 검출된 세균군)이 차지하는 비율은 호기조 < 무산소조 < 혐기조 순이었으나, 이와 반대로 아질산 산화세균(NIT로 검출된 세균)이 차지하는 비율은 혐기조 < 무산소조 < 호기조 순이었다. 생물막의 두께와 건조밀도 및 담체 무게당 부착된 미생물량은 각각 $180{\sim}188\;{\mu}m$, $38.5{\sim}43.9\;mg/cm^3$, $29.4{\sim}32.5\;mg/g$ 이었고, 담체에 부착된 총세균수 중 질화세균이 차지하는 비율은 NSO(3.2%)와 NIT(2.8%)가 거의 비슷하였으나, 각 반응조에 존재하는 부유성 질화세균, 즉 NSO($22.8{\sim}28.4%$)와 NIT($17{\sim}26%$)에 비해서는 부착성 질산화 세균의 비가 현저히 낮았다.

아동기 과체중 위험 인자로서의 TV시청시간, 사회계층요인, 부모의 과체중 및 부모의 활동수준 (Television Watering, Family Social Class, Parental Overweight, and Parental Physical Activity Levels in Relation to Childhood Overweight)

  • 윤군애
    • 대한지역사회영양학회지
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    • 제7권2호
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    • pp.177-187
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    • 2002
  • This study was done to determine the factors associated with childhood overweight in 721 sixth grade elementary school students, in Busan. The students' heights, weights, waist circumferences and triceps-skinfold thicknesses were measured using standard techniques. Other data were collected using a questionnaire that included information about physical activity, television watching, and the amount of exorcise taken during leisure times, family history of diseases related to obesity: social data including family income, parents'education and occupations, eating behaviors; parental weights and heights; and parental activity levels. Childhood overweight was defined as a body mass index at or above the 85th percentile for age and sex. The prevalence of overweight revealed no significant difference between sexes, (24.2% in boys and 22.03% in girls). The risk of childhood overweight was significantly greater if either the mother or the father were overweight. The odds ratio for childhood overweight associated with maternal overweight was 5.045 (94% CI : 3.262-7.801), and 2.727 (95% CI : 1.764-4.218) was the case for parental overweight. Children having a history of hear diseases had higher odds ratios than those who did not. The odds ratios for overweight associated with income were not different. However, a higher odds ratio for overweight was observed in children whose fathers had only an elementary or middle school education than those whore fathers had a high school or college education. Children whose fathers' occupations were service workers or shopkeepers (OR : 3.314, 95% C = 1.851-5.934) or had no occupation (OR = 3.756, 95% CI : 1.898-7.430) had a treater risk of overweight than those whose fathers'were professionals or once workers. The risk of overweight increased in children having more irregular meal times and faster eating times, rather than those having an intake pattern of high energy and sugar containing floods. The amount of exercise taken during leisure times, and daily physical activity showed no difference between overweight and non-overweight children. However, television watching time, especially on weekends, was greater in overweight children than in non-overweight children. Television watching time was positively correlated with BMI, triceps-skin(31d thickness, waist circumference and waist/height ratio. Therefore, television watching was found to be a useful predictor of overweight in children. Television watching in children was negatively related to paternal activity levels, and positively related to parental television watching time. In fact, fathers whose children were overweight were physically less active than fathers whose children were non-overweight. Parents appeared to be a strong influence on their children's physical activity levels. In conclusion, a low family social class, defined on the basis of the father's occupation or education, parental overweight, increased television watching, and unhealthy physical activity levels in parents were all considered risk factors for childhood overweight. Among these, television watching time and lack of physical activity were considered to be the most important risk factors that could be easily modified for the prevention of and intervention in, overweight in children.

일부 청소년의 체중조절과 관련된 요인에 관한 연구 -자아존중감, 신체만족도 및 중요도, 신체적 특성과 체형에 대한 인식을 중심으로- (The Factors Associated with Weight Control Experiences among Adolescents - Based on Self-esteem, Body-cathexis, Attitudes toward the Body, Anthropometric Characteristics and Perceptions of Body Shape -)

  • 허은실;강현진;이경혜
    • 대한지역사회영양학회지
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    • 제8권5호
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    • pp.658-666
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    • 2003
  • This study was carried out to investigate among adolescents (total=729) the relationship between their self-esteem, body-cathexis, their attitudes toward the importance of their bodies, their anthropometric characteristics, their perceptions of their body shapes and their experiences with weight control. The results are summarized as follows: The mean values for self-esteem and body-cathexis were generally low, but these values were significantly higher among boys than girls (p<0.01-0.001). However the mean values for their attitudes toward the importance of their bodies were relatively high and were significantly higher among girls than boys (p<0.01). The mean values for Percent Ideal Body Weight (PIBW) and Body Mass Index (BMI) were normal and no significant differences between the genders were observed. The distribution of the PIBW and the BMI values showed a higher rate for normal weights among the girls and a higher rate for underweightedness and obesity among the boys (p<0.01). With regard to their perception of their body image, among the boys, their current figures were almost identical with their idea of an ideal figure, but among the girls, their idea of an ideal figure was thinner than their current figure. The girls were more dissatisfied with their own body image than the boys (p<0.001). Fifty-four percent of the subjects had previous weight control experience, and the girls had significantly more experience than the boys (p<0.001). Their main reason for practising weight control was to lose weight (65.3%) Those who had more weight control experience had lower satisfaction with their body shapes, higher PIBW, higher BMIs or currently had fatter figures. Their standard image of their figures was influenced by TV (40.3%) and friends (36.9%). There was a weakly positive correlation between their self-esteem and their satisfaction with their body shapes, and a weakly negative correlation between their satisfaction with their body shapes and their attitudes toward the importance of their bodies. These results suggest the necessity for an educational program for adolescents as to foster a positive body image. Such a program should consider psychological factors such as self-esteem, satisfaction with body shape and attitudes toward the importance of the body.

고품질 땅콩나물 생산을 위한 최적 재배수온 조건 확립 (Establish of Optimum Cultivation Temperature for the Production of Peanut Sprouts)

  • 이규빈;박은지;허유;손병구;최영환;이용재;박영훈;서정민;강점순
    • 한국환경과학회지
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    • 제24권6호
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    • pp.763-767
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    • 2015
  • 땅콩나물 생산의 재배수온에 따른 발아성과 부패율 및 생육반응 검정한 결과 재배수온은 발아율에는 영향을 미치지 못했다. 반면 $25^{\circ}C$의 재배수온에서는 발아율이 가장 빨랐다. $30^{\circ}C$$35^{\circ}C$의 고온에서는 부패율이 각각 2.5%와 5.4%로 증가하였다. 따라서 $30^{\circ}C$ 이상의 재배수온은 땅콩종자의 부패율을 증가시켰고, $25^{\circ}C$에서는 부패율이 크게 문제되지 않았다. 재배수온은 하배축 길이생장과 직경생장에도 영향을 주었다. 생육 7일째 땅콩나물의 하배축 신장은 $25^{\circ}C$의 재배수온에서 가장 높았고, 다음이 $20^{\circ}C$였다. 따라서 고품질 땅콩나물 생산에 적용될 수 있는 최적 재배수온은 $25^{\circ}C$였다. 땅콩나물의 레스베라트롤 최적 생산을 위한 생육온도는 생육온도별 레스베라트롤 함량에는 차이가 없었지만 수량과 품질을 감안한다면 재배온도는 $25^{\circ}C$가 적당한 것으로 판단된다. 이러한 결과는 고품질 땅콩나물의 대량생산화를 구축하는 근간이 될 것이다.

3성분계 시멘트에서 FA 및 BS의 최적혼합비율 도출에 관한 연구 (A Study on Optimum Proportion of FA and BS for Ternary Cement)

  • 한천구;박성배
    • 한국건설순환자원학회논문집
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    • 제4권2호
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    • pp.143-148
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    • 2016
  • 본 연구는 3성분계 시멘트에서 FA와 BS의 최적혼합비율을 도출하기 위한 것이다. 즉, 혼화재 치환율 별 FA 및 BS의 다양한 혼합비율에 따른 모르타르의 기초적 특성을 파악하고자 하였다. 실험결과, 본 연구의 범위 내에서 다음과 같은 결론을 얻었다. 플로의 경우는 혼화재 치환율 및 FA의 혼합비율이 증가함에 따라 증가하는 것으로 나타났다. 공기량은 혼화재 치환율이 증가하고 FA의 혼합비율이 증가할수록 감소하였다. 단위용적질량은 혼화재 치환율 25% 및 45%에서는 공기량이 감소할수록 증가하는 것으로 나타났지만, 65% 및 100%에서는 FA 치환율 20%까지는 증가하였지만 그 이상에서는 FA의 저밀도 영향으로 감소하였다. 응결시간은 혼화재 치환율 및 FA의 혼합비율이 증가함에 따라 지연되는 것으로 나타났다. 압축강도의 경우는 재령 91일에 혼화재치환율 25% 및 45%에서 FA : BS의 비율이 40 :t 60인 배합에서 가장 우수한 강도 값을 나타내었다. 따라서 압축강도적인 측면을 종합적으로 고려할 때 혼화재 치환율 25% 및 45%인 경우에서 FA : BS의 비율 2 : 3인 경우가 본 연구의 범위 내에서는 최적의 혼합비율인 것으로 판명되었다.

친환경 무기질 고화재를 사용한 무시멘트 황토모르타르의 특성 (Properties of Cementless Loess Mortar Using Eco-Friendly Hardening Agent)

  • 정용욱;김성현;이동규
    • 한국건설순환자원학회논문집
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    • 제3권4호
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    • pp.355-365
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    • 2015
  • 본 연구에서는 친환경 무기질 고화재를 사용하여 무시멘트 황토모르타르의 유동성과 강도특성 및 내수성과 동결융해 등의 내구 특성을 검토하였다. 실험결과 황토모르타르의 재령 28일 압축 및 휨강도는 마사토와 황토 혼합비율에 관계없이 고화재 치환율이 증가할수록 증가하였고, 고화재 치환율에 관계없이 재령 14일까지의 강도증진효과는 크게 나타났으나 재령 14일 이후 강도증진 효과는 상대적으로 낮아 황토모르타르의 강도발현은 일반 콘크리트의 강도발현보다 빠른 것으로 나타났다. 또한, 고화재 10% 사용 시 평균 휨강도는 1.7MPa로 포장용 콘크리트의 재령 28일 휨강도 4.5MPa 이상을 만족시키지 못하였으나, 고화재 20%에서 약 4.0MPa, 고화재 30%에서 5.3MPa로 근접하거나 높게 나타나, 황토모르타르를 포장용 도로에 적용시 고화재 사용량은 최소 20% 이상 되어야 할 것으로 판단된다. 내수성 실험결과 흡수 건조의 반복은 황토의 혼합비율에 관계없이 질량을 감소시켰으며, 최대길이변화율은 황토 혼합비율과 고화재 치환율이 증가할수록 감소하는 것으로 나타났다. 동결융해 저항성 실험결과 동결융해 300 사이클에서 상대동탄성계수는 고화재 20%에서 75%, 고화재 30%에서 79%로 나타나, 황토모르타르의 상대동탄성계수 60% 이상을 만족시키기 위한 고화재 사용량은 20% 이상이 필요한 것으로 나타났다.