• 한국환경과학회지
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• 제27권9호
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• pp.753-762
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• 2018

The present study set out to investigate the adsorption of Cd(II) ions in an aqueous solution by using Peanut Husk Biochar (PHB). An FT-IR analysis revealed that the PHB contained carboxylic and carbonyl groups, O-H carboxylic acids, and bonded-OH groups, such that it could easily adsorb heavy metals. The adsorption of Cd(II) using PHB proved to be a better fit to the Langmuir isotherm than to the Freundlich isotherm. The maximum Langmuir adsorption capacity was 33.89 mg/g for Cd(II). The negative value of ${\Delta}G^o$ confirm that the process whereby Cd(II) is adsorbed onto PHB is feasible and spontaneous in nature. In addition, the value of ${\Delta}G^o$ increase with the temperature, suggesting that a lower temperature is more favorable to the adsorption process. The negative value of ${\Delta}H^o$ indicates that the adsorption phenomenon is exothermic while the negative value of ${\Delta}S^o$ suggests that the process is enthalpy-driven. As an alternative to commercial activated carbon, PHB could be used as a low-cost and environmentally friendly adsorbent for removing Cd(II) from aqueous solutions.

• 한국식품영양과학회지
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• 제30권1호
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• pp.6-13
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• 2001

The study was conducted to investigate the effect of the browning inhibitors such as PVPP(polyvinylpoly-pyrrolidone), A.A.(ascorbic acid) on nonezymatic browning factors [free sugar, total amino acid, organic acid, A.A., HMF (hydroxymethylfurfural)] and enzymatic browning factors [PRO (polyphenoloxidase) activity, polyphenol compounds] in concentrated apple juice during 90 days storage. Considering color value (L value, $\Delta$E), absorbance at 420 nm, concentrated apple juice during 90 days storage. Considering color the effect of browning inhibition. According to the storage period, the changes of nonenzymatic factors in concentrated apple juice added with browning inhibitors were similar to those in control (concentrated apple juice without browning inhibitors), which were the decreased of sucrose(0.24~0.35% at 90 days), the slight increase of glucose and fructose, the decrease of total amino acid (530.4~573.1 mg/10g at 90 days), same value of A.A. at 90 days (38.5~78.6 mg/100g), and the increase of HMF (27.8~30.6 mg/100g at 90 days). On the contrary, enzymatic browning factors were significantly inhibited in concentrated apple juice added with PVPP, judging from the slow increase of PRO activity and the significant decrease of initial value in polyphenol compounds (especially chlorogenic acid). These results suggest that PVPP plays an important role as enzymatic browning inhibitor, that is, a scavenger of polyphenol compounds by adsorption in concentrated apple juice.

• Journal of Forest and Environmental Science
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• 제31권1호
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• pp.1-6
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• 2015

Microwave assisted biodiesel production from crude Pongamia pinnata oil using homogeneous base catalyst (KOH) was unsuccessful because of considerable soap formation. Therefore, a two step process of biodiesel production from high free fatty acid (FFA) oil was investigated. In first step, crude P. pinnata oil was acid catalyzed using $H_2SO_4$ and acid value of oil was reduced to less than 4 mg KOH/g. Effect of sulfuric acid concentration, alcohol-oil molar ratio and microwave irradiation time on acid value of oil was studied. Result suggested that 1.5% $H_2SO_4$ (w/w), 6:1 methanol oil molar ratio and 3 min microwave irradiation time was sufficient to reduce the acid value of oil from 12 and 22 mg KOH/g to 2.9 and 3.9 mg/KOH/g, respectively. Oil obtained after pretreatment was subsequently used for microwave assisted alkali catalyzed transesterification. A higher biodiesel yield (99.0%) was achieved by adopting two step processes. Microwave energy efficiency during alkali catalyzed transesterification was also investigated. The results suggested a significant energy saving because of reduced reaction time under microwave heating.

• 한국환경과학회지
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• 제18권10호
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• pp.1181-1187
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• 2009

Results for application of RDF(Refuse Derived Fuel) to selected wastes in metropolitan and small and medium cities are as follows. The physical characteristics of waste are paper, plastic, food waste, and so on. The proximate analysis in P city showed 20.2% of moisture, 71% of combustible material, and 8.8% of ash on annual average. That in G city showed 31.6% of moisture, 59.5% of combustible material, and 8.9% of ash. Ultimate analysis in P city showed 52.04% of carbon, 7.02% of hydrogen, 28.80% of oxygen, 0.66% of nitrogen, and 0.09% of sulfur. Heating value was 3,363 kcal/kg. Ultimate analysis in G city showed 50.85% of carbon, 6.56% of hydrogen, 29.86% of oxygen, 0.79% of nitrogen, and 0.12% of sulfur. Heating value in the G city was somewhat lower than that in the P city with 2,632 kcal/kg. Thus, application of RDF in metropolitan city was more effective than that in small and medium cities. Heating value in mixture for the P city was lower than that in waste of the volume rate waste charge system alone by 143 kcal/kg. In proximate analysis, moisture, and combustible material were likely to be more adequate to RDF.

• Clinical and Experimental Reproductive Medicine
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• 제3권1호
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• pp.13-19
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• 1976

Serum levels of human placental lactogen have been measured by hemagglutination-inhibition reaction in 67 normal pregnant state and in 15 postpartum 24 hour state, HAIR is less sensitive and reliable method than radioimmunoassay, but simple, rapid, less expensive and fairly accurate, so it is more helpful in screening of large antenatal population with or without high risk complications. 1) Sensitivity of HPL-HAIR test kit was $0.1{\mu}g$/ml of H.P.L. serum level and had no cross reaction to HCG or male serum or non-pregenant female or newborn infant, 2) H.P.L. value was around $2{\mu}g$/ml until 24th week of pregnancy and rose to $6{\sim}8$ ${\mu}g$/ml continuously until about 36th week of pregnancy and then slightly decreased or stationary. 3) H.P.L. value in postpartum 24 hour state was undetectable. 4) There was poor correlation between maternal serum H.P.L. value at term and baby weight.

• Journal of Preventive Medicine and Public Health
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• 제26권1호
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• pp.49-64
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• 1993

규폐증의 신기능 장애 평가를 위한 기초 자료를 제공하기 위하여, 우리나라 일부 지역의 진폐요양기관에서 규폐증으로 치료중인 환자 58명을 실험군으로 하고 폐결핵으로 6 개월이상 치료중인 환자 40명을 결핵 대조군 그리고 일반사무직 근로자 51명을 건강대조군으로하여, 신기능 장애의 예민한 지표로 알려진 요중 N-ncetyl-$\beta$-D-glucosaminidase (NAG) 활성치를 측정하여 얻은 바를 아래와 같이 요약 한다. 1. 조사대상자 전체의 혈중 요소질소와 혈청 크레아티닌은 대상자 모두에서 참고치내에 있어 임상적으로 신장장애의 소견을 보이지 않았으나, 요중 NAG 활성치는 $7.25{\pm}7.31U/g\;creatinine$으로서 신기능 장애 선별기준 이상의 측정치를 보여 보다 민감한 검사 결과를 나타내었다. 2. 규폐증군의 요중 NAG 활성치는 $11.98{\pm}9.05U/g\;creatinine$으로서 결핵대조군($5.71{\pm}4.33U/g\;creatinine$) 및 건강대조군($3.63{\pm}1.67U/g\;creatinine$)에 비하여 통계학적으로 유의하게 증가되어 있었으나(p<0.05), 결핵대조군과 건강대조군에서는 유의한 차이를 나타내지 않았다(p>0.05). 3. 결핵대조군에서 결핵의 병증에 따라 요중 NAG 활성치가 증가되는 양상을 보였으나 통계학적으로 유의 하지않았고(p>0.05), 치료약제중 신장애 유발 항결핵제를 사용한 대상자에서 요중 NAG 활성치는 유의하게 증가되어 있었다(p<0.05). 4. 규폐증군에서 결절의 크기가 클수록 그리고 신장애 유발 항결핵제를 사용한 자 및 발병기간이 짧았던 자의 경우 요중 NAG 활성치가 증가되는 양상을 보였으나, 통계학적으로 유의한 차이는 아니었다(p>0.05). 5. 신독성 항결핵제 사용자를 제외한 요중 NAG 활성치는 건강대조군과 결핵대조군에서 각각 3.63U/g creatinine, 3.60U/g creatinine으로 차이를 보이지 않았으나, 규폐증군에서는 10.90U/g creatinine 으로 현저히 증가되어 있었다. 이상의 결과로 규폐증에서는 일반적인 건강진단 항목상의 신기능 검사에 이상소견을 보이지 않은 경우라도 신장기능의 변화가 동반될 수 있으며, 요중 NAG 활성치를 분진 폭로 근로자에게 적용하면 산업보건학적 측면에서 근로자의 건강관리를 위하여 매우 유익한 자료가 될 것으로 생각한다.

• 한국해양공학회지
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• 제16권4호
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• pp.42-47
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• 2002

This paper describes the effect of loading rate, specimen geometries and material properties for Mode II interlaminar fracture toughness of hybrid composite by using end notched flexure(ENF) specimen. In the range of loading rate 0.5~2mm/min, there is found to be no significant effect of loading rate with the value of critical energy release rate( $G_{IIc}$). there is no dependence of the interlaminar fracture energy upon the specimen width over the specimen widths examined. The value of $G_{IIc}$ for variation of initial crack length are nearly similiar values when material properties are CF/CF and GF/GF, however, the value of $G_{IIc}$ are highest with the increasing intial crack length at CF/GF. The values of $G_{IIc}$ for variation material properties are higher with the increasing moulding pressure when moulding pressures are 307, 431, 585㎪. The SEM photographs show good fiber distribution and interfacial bonding of hybrid composites when the moulding is the CF/GF.e CF/GF.

• 한국의류학회지
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• 제28권2호
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• pp.354-363
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• 2004

PCDD/F (Polychlorinated dibenzo-p-dioxins and dibenzofurans) in both of treated fabric and untreated fabric for working clothes of a municipal waste incineration were determinated. The treated fabric for working clothes was developed for less exposure of PCDD/F in municipal waste incinerations. The total concentrations of PCDD/F in some parts such as surface, middle layer, inside for treated and untreated fabric were investigated. The I-TEQ value of surface was 0.23370ng TEQ/g for treated fabric, 0.15355ng $.$ TEQ/g for non-treated fabric. On the other hand, the value of middle layer was 0.00077ng $.$ TEQ/g, 0.00177ng $.$ TEQ/g, respectively. The surface of the treated fabric containing high levels PCDD/F was caused by absorption of them. Therefore, PCDD/F of the treated fabric in middle layer was less I-TEQ value than that of the untreated fabric. The treated fabric makes effect on preventing PCDD/F from permeating into human body.

• 약학회지
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• 제47권6호
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• pp.422-431
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• 2003

The use of recombinant human erythropoietin (rhEPO), a stimulator of erythropoiesis, banned in sports because of the medical risk associated with thrombosis. Due to analytical difficulties to differentiate between natural human EPO (hEPO) and rhEPO, blood parameters of erythropoiesis such as contents of hemoglobin (cut-off value <17.5 g/d l for man, and < 16.0 g/dl for women), hematocrit and reticulocytes (cut-off value <2.0%) were measured to focus the misuse of rhEPO. We conducted anti-doping test for 122 blood samples of the World Cup athletes. The mean values of key parameters are as follows; 14.5$\pm$1.0 g/dl for hemoglobin, 41.7$\pm$2.8% for hematocrit, and 1.3$\pm$0.4% for reticulocyte. Blood sample was found to be stable up to 8 hours for the reticulocyte measurement. In addition, the soluble transferrin receptor and ferritin levels were measured by immunoassay methods using plasma samples (n=28) in which the mean value was 0.8$\pm$0.5 $\mu\textrm{g}$/$m\ell$ and 54.6$\pm$33.7 ng/$m\ell$, respectively. The results indicate that all samples tested were negative for the blood parameters of indirect anti-doping test for hEPO misuse. The statistical evaluation suggest that several other parameters such as red blood cell, mean corpuscular hemoglobin concentration, mean corpuscular volume, mean corpuscular hemoglobin and white blood cell could be considered as factors influencing hEPO function in addition to five parameters mentioned.

• 한국식품위생안전성학회지
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• 제24권1호
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• pp.12-18
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• 2009

열풍건조 및 동결건조된 와송의 열수추출물을 대두유 및 돈지에 0.1, 0.5 및 1.0 g/100 mL의 농도로 첨가하고 $180^{\circ}C$에서 가열하는 동안 유지의 산화 안정성을 측정하였다. 유지의 색도는 가열시간이 경과될수록 증가되었으며, HWE 첨가구에서 색도가 다소 높았다. 아니시딘가는 가열시간이 경과될수록 유의적으로 증가되었으나, 48시간 가열 후 0.5 및 1.0 g/100 mL의 HWE 첨가구, 1.0 g/100 mL의 FWE 첨가구를 제외하면 모든 실험구에서 대조구보다 낮았다. 돈지에서는 시료의 첨가량에 관계없이 모든 실험구에서 대조구보다 낮았다. 산가는 가열시간이 길어짐에 따라 유의적으로 증가하였으나, 대두유에서 시료의 첨가량에 따른 유의차는 없었으며, 가열 48시간 이후 HWE 첨가구가 FWE 첨가구에 비해 다소 낮았다. 과산화물가도 HWE 첨가구가 FWE 첨가구보다 낮았다. TBA가는 대두유에서 가열 24시간 이후에 대조구보다 낮았으며, 돈지에서는 가열전기간 동안 대조구보다 낮았다. 따라서 와송 열풍건조시료는 동결건조 시료에 비해 항산화능이 우수하며, 돈지의 가열시 산화안정성에 효과가 있을 것으로 생각되었다.