• Advances in materials Research
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• 제5권2호
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• pp.121-130
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• 2016

In an attempt to reach a balance of performances in homo-polypropylene based system, the effects of single and hybrid reinforcements inclusions comprising calcium carbonate nanoparticles (2, 4 and 6 phc) and glass fibers (10 wt.%) on the mechanical and thermal properties were investigated. Different samples were prepared by employing twin-screw extruder and injection molding machine. In morphological studies, the uniform distribution of glass fibers in PP matrix, relative adhesion between glass fibers and polymer, and existence of nanoparticles in polymer matrix were observed. $PP/CaCO_3$ (6 phc) as compared to pure PP and PP/GF had superior tensile and flexural strengths, impact resistance and deformation temperature under load (DTUL). $PP/GF/CaCO_3$ (6 phc) composite displayed comparable tensile and flexural strengths and impact resistance to neat PP, while its tensile and flexural moduli and deformation temperature under load (DTUL) were 436%, 99% and $26^{\circ}C$greater respectively. The maximum impact resistance was observed in $PP/CaCO_3$(6 phc). The highest DTUL was perceived in PP hybrid nanocomposite containing 10 wt.% glass fiber and 4 phc $CaCO_3$ nanoparticle.

• 공업화학
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• 제33권1호
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• pp.109-112
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• 2022

Lime has been used for the neutralization of acidic waste because it is cheap and available in large quantities. The resulting sludge often contains a considerable amount of unreacted lime due to alkali overdosing, even during automatic neutralization processes, which mainly arises from the poor solubility of lime. The sludge cake from lime neutralization of Ilkwang Mine also contained high percentages of calcium and magnesium. The elemental content of the sludge cake was compared with those obtained from a simulation of the lime neutralization facility installed at Ilkwang Mine. A Goldsim^® model estimated the degree of lime overdosing to be 19.1% based on the fractions of ferrous oxide. The analysis suggests that resolubilization of aluminum hydroxide could occur in the settling basin, in which pH exceeded 10 due to the continued dissolution of the overdosed lime. The present study demonstrated that chemical analysis of sludge combined with process simulation could provide a reasonable estimate of mass balance and chemistry in a neutralization facility for acid mine drainage.

• Journal of Nutrition and Health
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• 제53권1호
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• pp.68-82
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• 2020

본 연구대상자의 평균 나이는 78.6세로 75세 이상이 75.0%를 차지하였으며, 만성질환을 2개 이상 갖고 있는 노인이 55.4%였다. 가구 유형에서 독거노인의 비율이 40.7%였고, 70.6%의 노인이 식사 준비를 본인이 하는 것으로 나타났다. 전체 대상자의 평균 NQ-E 점수는 61.9점으로 전국 단위 조사와 비교하면 '중상'에 속하였다. 균형, 절제, 식행동 영역은 전국 단위 조사의 '중상'에 속하였고 다양 영역은 '중하'에 속하였다. 여자노인이 남자노인보다 절제와 식행동 영역의 점수가 높았다. 독거노인은 배우자동거노인에 비해 다양성 영역의 점수가 낮았다. 다양성 영역은 소득과 교육수준이 높은 노인의 점수가 높았고, 절제 영역은 소득수준이 낮은 노인과 2개 이상의 만성질환을 보유하고 있는 노인의 점수가 높았다. 영양 보충제를 1개 이상 섭취하는 노인이 영양지수 총점수와 균형, 다양성 및 식행동 영역의 점수가 높았다. 연구 대상자의 51.0%가 모니터링 필요군으로 영양지수 평균은 54.8점이었고, 양호군은 49.0%로 영양지수는 69.3점으로 유의하게 높았다. 본 연구대상자의 에너지, 니아신, 리보플라빈, 비타민 A의 섭취량이 EAR 미만으로 나타났고, 비타민 A, 니아신, 비타민 C, 칼슘 등은 영양권장량 대비 75% 미만으로 섭취하고 있었다. 모니터링 필요군의 1일 에너지 섭취량과 단백질, 티아민, 리보플라빈 및 비타민 C 섭취량이 양호군에 비해 유의하게 낮았다. 또한 모든 영양소의 영양소 적정섭취비 (NAR)가 1 미만이었으며, 모니터링 필요군이 양호군에 비해 비타민 A, 티아민, 리보플라빈, 비타민 C, 칼슘 및 칼륨의 NAR이 유의하게 낮았다. 비타민 A, 리보플라빈, 니아신, 비타민 C, 칼슘, 칼륨의 INQ가 1보다 낮아 에너지 섭취량에 비해 부족한 영양소로 나타났다. 1일 식품섭취량에서 모니터링 필요군이 양호군에 비해 총 식품 섭취량과 채소류 및 버섯류 섭취량이 유의적으로 낮았다. 본 연구 결과 노인 영양지수가 높은 군이 낮은 군보다 24시간 회상법으로 조사한 식품섭취조사에서 단백질을 비롯한 대부분의 필수영양소 섭취 수준이 유의적으로 높은 것으로 나타나서, NQ-E가 노인의 식생활 및 영양 상태를 평가할 수 있는 타당한 도구임을 보여준다.

• 한국토양비료학회지
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• 제45권4호
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• pp.610-613
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• 2012

산성토양을 개량하기 위한 목적으로 패화석을 시용하여 보리의 생육, 수량과 품질 및 토양 미생물상을 조사하였다. 패화석 처리로 석회고토나 무처리에 비해 $m^2$당 수수와 천립 중이 높아져 보리의 수량은 석회소요량 처리구인 패화석 $3.09Mg\;ha^{-1}$ 시용에서 $5.53Mg\;ha^{-1}$로 가장 많았으며 석회고토 동량의 패화석 처리구도 $5.23Mg\;ha^{-1}$로 석회고토 $5.20Mg\;ha^{-1}$ 보다 증대되었다. 패화석 처리구는 석회고토 처리구 보다 보리 단백질 함량은 0.5~0.7% 낮아져 농산물의 품질향상에 미치는 영향은 석회고토보다 양호한 것으로 판단되었다. 토양 pH는 패화석과 석회고토 시용으로 무처리 보다 0.5~0.6 정도 상승되었고 치환성 Ca 함량은 패화석 $3.09Mg\;ha^{-1}$ 처리구에서 $7.5cmol_c\;kg^{-1}$으로 가장 높았으며 석회고토 처리구는 치환성 Mg 함량이 $2.5cmol_c\;kg^{-1}$으로 가장 높게 나타났다. 패화석 $3.09Mg\;ha^{-1}$ 및 $2.38Mg\;ha^{-1}$ 처리구는 석회고토 $2.38Mg\;ha^{-1}$ 처리구에 비해 토양의 세균 밀도는 각각 60.9 및 $69.7{\times}10^6CFU\;g^{-1}$로서 높은 반면 방선균 밀도는 각각 32.4, $45.4{\times}10^5CFU\;g^{-1}$로서 낮았다.

• 한국식품과학회지
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• 제36권5호
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• pp.701-710
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• 2004

건식분해에 의한 AAS법과 습식분해에 의한 ICP법을 이용하여 조제분유 중 칼슘 함량을 측정하는 과정중의 측정불확도를 비교산정하기 위하여 분석결과에 영향을 주는 불확도 인자를 파악하고 각각의 불확도를 계산하였다. 계산은 GUM(Guide to the expression of Uncertainty in Measurement)과 Draft EURACHEMCITAC Guide에 근거한 수학적 계산 및 통계처리 방법에 의해 처리하였다. AAS에 의한 칼슘 측정시 uncertainty source로서 시료의 무게, 시료의 최종전량, 시료의 희석 그리고 기기에 의한 측정결과값 등이 작용하였다. Uncertainty source의 개별구성요소인 uncertainty component는 저울의 안정성, 분해능, 재현성, 표준액의 순도, 분자량, 농도, 표준액 희석 및 시료의 희석, 검정선, 회수율 그리고 분석기기의 정밀성, 재현성 및 안정성 등이 작용하였으며 A type 또는 B type으로 불확도를 산정하였다. ICP에 의한 칼슘 측정시 uncertainty souce와 component는 시료의 희석부분을 제외하고 AAS와 동일하게 작용하였다. 칼슘함량과 측정불확도가 보장된 인증표준물질인 Infant Formula SRM 1846을 사용하여 칼슘함량을 측정한 결과 AAS법에 의한 결과값과 ICP법에 의한 결과값은 각각 $359.52{\pm}23.61\;mg/100g$, $354.75{\pm}16.16mg/100g$으로 측정되었다. 2가지 방법 모두 인증 값인 칼슘함량 $367{\pm}20mg/100g$의 범위내로 측정되었으며, CRM에서 보장된 균일성과 실험오차를 고려하면 유사한 결과가 산출되었음을 알 수 있다(p<0.05). 측정불확도를 시험담당자가 시험수행시마다 파악하고 계산하기란 시간적, 인력적 제약과 업무효율적 측면에서 현실적으로 어려운 점이 많다. 그러나, 본 연구에서와 같이 시험과정 중의 분석오차 발생인자를 파악하고 최종 시험결과에 미치는 영향정도를 산출하여 그 인자들을 최소화하여야 할 것으로 사료된다. 즉, 측정불확도는 불확도인자 설정과 계산에 있어서 다양한 방법이 제시될 수 있으므로 수치화된 결과값 그 자체보다는 표준시약의 소급성 유지, 시험기구의 교정 관리, 시험실 환경 관리, 분석기기의 최적상태 유지 및 개인숙련도 향상 등과 같은 노력을 통해 시험결과의 품질을 최상으로 유지하는 척도로 활용되어야 할 것으로 사료된다.

• Journal of Nutrition and Health
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• 제28권7호
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• pp.653-674
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• 1995

This study was aimed at comparing the dietary patterns of university female students according to their residence type. As for subjects, one hundred and twenty students of Kongju national university were chosen as a total. They were devided into three groups ; those who live in family home, or university dormitory, or self-boarding house. In this study, intakes of food and nutrient and dietary behaviors of each group were investigated through two-day food records and questionnaire. The result was that mean daily intakes of calcium and iron were lower than RDAs in all groups. According to residence type, subjects of family home and self-boarding seemed to have more serious problem in the nutrients mentioned above considering the proportions of less than 2/3 of RDAs. Especially, iron status was poorer than any other nutrients in the aspects of this proportion and food source. Iron was taken largely from vegetable foods which were recognized as a source of low bioavailability of iron. The average distribution ratios of breakfast, lunch, dinner and snack to total calorie intake was 22, 29, 30 and 19. Thus, it proved that breakfast tended to be more negligent than any other meals, and that snack was an important means to give nutrients for subjects. This meal pattern might be one of the factor for the decrease of the dietary quality. Processed foods were founded to be an important source for providing nutrients. Percentages of calorie, carbohydrate and fat consumed by processed foods to total nutrients. Percentages of calorie, carbohydrate and fat consumed by processed foods to total nutrients intake were 30.6, 29.5 and 46.2. However, other nutrient intakes from processed foods such as vitamin and mineral were small. And processed foods which give nutrients were mainly cereal products like ra myon, bread, and milk and milk products. Consequently, processed foods seemed to be selected as a combinient substitute food which supply calorie to fill their hunger. According to the living type, dormitory students had them more frequently than any other groups. Food habit score was within the category of poor or fair. Particularly, the score of self-boarding students was the lowest of groups(p<0.05). The major dietary problems were small or overating, missing meal and irregular eating. The degree of these problems was a little different among groups(P<0.01). Nineteen kinds of food were consumed per day, and family home and self-boarding students had foods less variously than dormitory students(P<0.05). Proportions of skipping breakfast, lunch and dinner were 20.8, 12.5 and 8.3%. Accordingly, breakfast was missed more often than any other meals. And self-boarding students missed breakfast more often than any other groups. As a conclusion, subjects should take more calcium and iron, and eat diverse foods to improve their nutritional status. And it is also necessary that breakfast should be regarded more importantly, and that processed foods should be taken considering nutritional balance. In view of residence type, subjects of family home or self-boarding had more dietary problems than dormitory subjects. Thus, these results suggest that university female students might have low ability of meal management, and dietary patterns were different by their residence type. Therefore, nutrition education for them should be carried out with respect to dewelling environment.

• 대기
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• 제29권4호
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• pp.403-416
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• 2019

Precipitation samples were collected at the GAW Stations in Anmyeon-do and Gosan for 10 years (2008-2017) to analyze pH, electrical conductivity and NH₄⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, SO₄^2-, NO₃^-, Cl^-, and F^- ions. From the analysis, the correlation between pH and rainfall, the composition of precipitation and comparison with other regions, and the results of neutralization characteristics by seasonal and pH were determined. In the comparison of ion balance and conductivity for the validation of analytical data, the correlation coefficients were within the range of 0.996~0.999, implying good linear relationship. The volume-weighted pH of the Anmyeon-do and Gosan areas were 4.7 and 4.9, respectively. The pH of the rainfall was affected by washout and rainout in both areas. The ionic strength of precipitation at Anmyeondo and Gosan were 0.42 ± 0.63 mM and 0.37 ± 0.75 mM, indicating about 27.6% and 35.3% of the total precipitation as per a pure precipitation criterion (10^-4 M), respectively. The composition ratio of ionic species were 44.7% and 57.5% for marine sources (Na⁺, Mg²⁺, Cl^-), 40.6% and 22.2% for the secondary inorganic components (NH₄⁺, nss-SO₄^2-, NO₃^-), and 5.6% and 4.0% for the soil source (nss-Ca²⁺), respectively. The neutralization factor of Anmyeon-do and Gosan were 0.43~0.65 and 0.34~0.48, and the neutralization factors of calcium carbonate were 0.15~0.34 and 0.25~0.30, respectively. Thus, both regions have the highest rate of neutralization caused by ammonia. As pH increased in Anmyeon-do and Gosan, change in calcium carbonate became greater than that in ammonia.

• Journal of Nutrition and Health
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• 제14권4호
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• pp.200-208
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• 1981

A survey was conducted from January 23 to 31 and February 14 to 18, 1981, in Whaseounggun, Kyunggj-do, to investigate the dietary and nutritionary status, and prevalence of parasitic infection of the fertile women, in an attempt to provide an integrative perspective on the rural family health programmes. The results are summarised as follows; The total number of fertile women, randomly selected, was 197 ; 21 women were in the latter half of pregnancy; 38 women, lactating, the remaning, non-pregnant. Average age of the subjects was 31.4 years; average number of children, 2.7; average number of abortion, 0.9; average family number in home, 5.5. The families had a mean income of \ 2,470,000 per fear. The majority, 83.8% of the families, were engaged in farming. 61.4% of the subjects had completed schooling 6 years or less. The mean energy intake of the lactating women was 73.4% of the recommended allowance, while that of non-pregnant and pregnant women reached 86.9 to 88.6% of the recommendation. In the average diet of the subjects, carbohydrates contribute 74.6 to 81.7% of the total energy intake; protein 11.3 to 11.9%; fat 7.0 to 13.9%. Protein intake of non-pregnant, pregnant, and lactating women met 72.6%, 60.8%, and 65.2% of allowance, respectively; and those proteins were mainly derived from vegetable sources. The subjects ingested less than one-half of the allowances for iron, calcium, vitamin A, and riboflabin ; in contrast, thiamin and ascorbic acid levels were adequate or fairly acceptable. There were significant correlations of meal balance and food diversity scores to the mean intake levels of protein, calcium, iron, vitamin A, thiamin, and riboflavin. Only 10% of the pregnant women and 11.4% of non-pregnant and lactating women reached the acceptable level of hemoglobin. Positive prevalence of parasitic infection was found among about one-third of the subjects, 30.3% of women. Hematologic findings had no significant correlation to parasitic infection.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1542-1548
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• 2001

Wheat straw was treated on laboratory scale with 4% urea at a moisture level of 50% along with different amount of HC1 to fix various levels of ammonia (30, 40, 50 and 60%) and stored for 4 weeks. Result, revealed a significant (p<0.01) increase in CP content of the samples where HC1 was added. The CP content of the straw was only 7.8%, which increased to 14.1, 16.0, 15.0 and 15.2% with the addition of acid. Similarly the concentrations of NDF, ADF and hemicellulose was significantly different due to HC1 addition. The level of HC1 recommended was to trap 30% ammonia as there was not significant difference in CP content of straw due to addition of 4 levels of acids. Results of in vivo experiment conducted on nine buffaloes divided randomly into three groups of three animals in each revealed no significant difference in the intake of DM, OM, NDF, ADF, cellulose and hemicellulose in group I (ammoniated straw), group II (HC1 treated ammoniated straw) and group III (HC1 treated ammoniated straw + 1 kg barley grain), but the intake of CP was significantly (p<0.01) more in group III as compared to other 2 groups. The digestibility of DM, OM and CP was significantly (p<0.01) more in groups where HCI treated straw was fed as compared to only ammoniated straw fed group, whereas there was no significant difference in the digestibility of NDF, ADF and cellulose in 3 groups. Intake was significantly higher of nitrogen (p<0.05), calcium (p<0.01) and phosphorus (p<0.01) in group III as compared to other two groups. Animals in all the 3 groups showed positive nitrogen, calcium and phosphorus balance, though the balances of all the 3 nutrients were significantly higher in group III as compared to other 2 groups. Rumen fermentation study conducted in 3 rumen fistulated buffaloes in $3{\times}3$ latin square design offering the same 3 diets as in group I to III revealed that rumen pH was alike statistically in 3 groups and at various time intervals. The mean ammonia-N concentration was significantly (p<0.01) more in group II and III as compared to group I. The mean TVFA concentration (mM/100 ml SRL) were 6.46, 7.84 and 8.47 in 3 groups respectively and different statistically (p<0.01). Results revealed no significant difference in the activities of carboxy methyl cellulase, urease or protease at both the time of sampling (0 h and 4 h) in all the 3 groups of animals.

• 한국토양비료학회지
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• 제37권6호
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• pp.383-387
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• 2004

농가에서 관리하는 9년생 후지품종의 사과 과수원에 패화석과 석회고토의 중화량를 시용하여 작물생육과 토양 화학성 변화를 조사한 결과는 다음과 같았다. 석회를 시용하지 않은 처리구의 토양은 시험전후 pH가 5.6으로 차이가 없었으나, 패화석과 석회고토 처리구에서는 Ca, Mg 함량이 증가되고 pH가 5.6에서 6.8로 높아져 패화석은 석회고토 처리구와 동등의 산도교정 효과가 있었다. 패화석과 석회고토 시용으로 사과나무 신초의 초장과 신초수, 신초경이 증가되었으며, 석회 무시용에 비해 간경과 주지경의 직경이 연간 0.7 및 1.0 mm 증가하였고, 부주지경의 증가는 패화석과 석회고토 시용이 각각 1.7 및 1.8 mm 증가하여 사과나무의 생육에 효과가 있는 것으로 나타났다. 패화석과 석회고토 처리로 시기별 엽록소함량은 차이가 없었으나 건물중 변화는 10월 23일 조사시 무시용27.3% 대비 패화석과 석회고토 시용이 각각 33.1 및 31.0%로서 높았다. 시기별 엽중 무기성분으로 질소함량은 무시용 대비 패화석과 석회고토 시용으로 함량이 증가하였으며, CaO 함량은 큰 차이가 없었고, Mn 함량이 높았다. 사과의 당도, 경도 및 산도에 대한 패화석 시용효과는 무처리와 비교해 차이가 나타나지 않았으며, 석회고토 처리시 경도는 석회 무시용에 비해 낮았다. 패화석 시용시 색도는 황색도가 약간 높았으나 적색도에서는 낮았으며, 선명도는 처리간 차이가 나타나지 않아 패화석 시용이 사과의 품질 향상에는 영향을 미치지 못하였고 수량은 $37,000kg\;ha^{-1}$로 무시용 대비 5% 증수되었다.