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Adsorption of Cd(II) in Aqueous Solution by Peanut Husk Biochar (생물소재인 땅콩껍질 바이오 차를 이용한 수용액의 Cd(II) 제거)

  • Choi, Hee-Jeong
    • Journal of Environmental Science International
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    • v.27 no.9
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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.

The Browning Reaction and Inhibition of Apple Concentrated Juice (사과농축액의 갈변현상 및 그 억제)

  • 배수경;이영철;김현위
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.1
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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.

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Microwave Assisted Energy Efficient Biodiesel Production from Crude Pongamia pinnata (L.) Oil Using Homogeneous Catalyst

  • Kumar, Ritesh;Sethy, A.K.
    • Journal of Forest and Environmental Science
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    • v.31 no.1
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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.

Study on applicability of RDF in Municipal Waste Landfill Site (생활폐기물매립장에서의 RDF 적응가능성에 대한 연구)

  • Kim, Jung-Kwon
    • Journal of Environmental Science International
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    • v.18 no.10
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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.

H.P.L. Value in Serum of Normal Pregnancy and Pospartum State by Hemagglutination-Inhibition Reaction (정상(正常) 임산부(妊産婦)의 혈청중(血淸中) H.P.L.의 면역학적(免疫學的) 측정(測定)에 관(關)한 연구(硏究))

  • Chung, Ae-Rhee;Shin, Myun-Woo
    • Clinical and Experimental Reproductive Medicine
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    • v.3 no.1
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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.

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Assessment of Renal Function in Silicobis with Urinary N-acetyl-$\beta$-D-glucosaminidase Activity (규폐증환자의 신기능 평가를 위한 요중 N-acetyl-$\beta$-D-glucosaminidase활성치 측정의 의의)

  • Lee, Hoo-Rak;Kim, Don-Kyoun;Lee, Su-Il;Cho, Byung-Mann;Kim, Wha-Jo
    • Journal of Preventive Medicine and Public Health
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    • v.26 no.1 s.41
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    • pp.49-64
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    • 1993
  • To provide the basic data for assessment of renal dysfunction related to silicosis, urinary N-acetyl-$\beta$-D-giucobarninidase(NAG) activity known as a sensitive markers for early renal damage were measured in 58 silicosis patients, and control subjects of 40 pulmonary tuberculosis Patients and 51 official workers. The results were summarized as fellows. 1. The values of blood urea nitrogen and serum creatinine in all subjects were within reference limits. But the mean value of urinary NAG activity($7.25{\pm}7.31U/g\;creatinine$) was beyond reference value and more sensitive test than others. 2. The mean value of urinary NAG activity in silicosis group was $11.98{\pm}9.05U/g\;creatinine$ and significantly higher than in tuberculosis and healthy group(p<0.01), but the mean values of NAG activity in tuberculosis and healthy group were not different(p>0.05). 3. The value of NAG activity in tuberculosis had a tendency to be increased according to severity of disease, but that was not significant(p>0.05). The value of NAG activity was increased significantly by use of nephrotoxic antituberculosis drugs(p<0.05). 4. The value of NAG activity in silicosis had a tendecy to be increased according to the size of nodule, use of nephrotoxic antituberculosis drugs and shortness of onset duration, but the increase was not significant(p>0.05). 5. After excluding the users of nephrotoxic antituberculosis drugs, the mean values of NAG activity in healthy control and in tuberculosis control were same as 3.63 U/g creatinine and 3.60 U/g creatinine, respectively. But the mean value of NAG activity in silicosis group was remarkably increased as 10.90 U/g creatinine(p<0.01). As above results, even though there are no abnormal finding in screening renal function test, silicosis can be related with renal dysfunction. And it will be very useful to apply urinary NAG activity in health management of workers exposed to dust.

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A Study on Mode II Interlaminar Fracture Toughness of Hybrid Composites (하이브리드 복합재료의 모드II 층간파괴인성치에 관한 연구)

  • 김형진;박명일;곽대원;김재동;고성위
    • Journal of Ocean Engineering and Technology
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    • v.16 no.4
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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.

Determination of PCDD/F in Working Clothes of a Municipal Waste Incineration (생활폐기물 소각장 작업복 샘플의 다이옥신 분석)

  • 박순자;신정화;신정숙;정명희;안윤경
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.2
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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.

Blood Analysis for Indirect Doping Control of Erythropoietin in Sports (운동선수들의 혈액분석을 통한 Etrythropoietin 간접도핑검사)

  • 이정란;김소영;홍지연;김명수;최명자
    • YAKHAK HOEJI
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    • v.47 no.6
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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.

Effect of Wa-song(Orostachys japonicus A. Berger) Extract on the Oxidative Stability of Edible Oil During its Heating (식용유지의 가열시 와송 추출물이 산화안정성에 미치는 영향)

  • Lee, Soo-Jung;Shin, Jung-Hye;Seo, Jong-Kwon;Sung, Nak-Ju
    • Journal of Food Hygiene and Safety
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    • v.24 no.1
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    • pp.12-18
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    • 2009
  • This experiment was conducted to investigate the effect of wa-song (Orostachys japonicus A. Berger) extracts on the oxidative stability of edible oil. Wa-song was dried from hot air (HWE) and freeze (FWE), and then they were extracted by hot water. The different levels (0.1, 0.5 and 1.0 g/100 mL) of HWE and FWE were added to soybean oil and lard. The chromaticity of edible oils was generally increased with prolonged heating time and HWE was higher than FWE. The anisidine value showed significant increase during heating for 48hrs. After heating for 48 hrs, it was lower than control, except for HWE added sample of 0.5 and 1.0 g/100 mL, FWE added sample of 1.0 g/100 mL. In lard, it was lower in sample added wa-song extract than control. The acid value was not significant by added amount of wa-song. Its value in HWE added sample was lower than FWE, after heating for 48 hrs. POV was lower HWE than FWE, also. After heating for 24 hrs, TBA values in soybean oil containing HWE and FWE added sample was lower than control. In lard, its value in HWE and FWE added sample was lower than control during heating for $12{sim}48\;hrs$. Therefore, those results suggested that HWE has higher antioxidant activity than FWE added sample, and then oxidative stability of HWE in edible oil was more potential for lard during its heating.