• Title/Summary/Keyword: ECF

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Interaction of Oxygen and Chlorine Dioxide in Pulp Bleaching (II) - Studies on the Degradation of Carbohydrates - (펄프 표백시 산소와 이산화염소의 상호작용 (제2보) - 탄수화물의 분해에 관한 연구 -)

  • 윤병호;김세종;최경화;김영훈
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.1
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    • pp.37-42
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    • 2004
  • ECF and TCF bleaching methods are favored in bleaching plants over the world due to the increasing environment constraints. However, interaction of main stages(D and O stage) in ECF bleaching have not been understood completely yet. The degradation of holocellulose as a carbohydrate model compound was investigated by SEC(size exclusive chromatography) to estimate the change of its molecular weight distribution after O and D stage combination treatment. The molecular weight distribution of holocellulose was observed in two divisions(higher and lower molecular portions). It was also shown that DO sequence was more effective than OD, and DOD or ODO was more effective than DO. D stage had a little effect on the degradation of holocellulose, while the degradation of holocellulose increased as the time of the first O stage increased.

Manufacture of Printing and Writing Papers from Old Corrugated Containers (OCC) (Old Corrugated Containers (OCC)로부터 인쇄·필기용지 제조)

  • Lee, Goo;Ahn, Byoung-Jun;Paik, Ki-Hyon
    • Applied Chemistry for Engineering
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    • v.10 no.3
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    • pp.367-373
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    • 1999
  • Increasing consumer demand for recycle of most paper products is challenging manufacturers to use lower value raw materials while maintaining high quality. This study was carried out to investigate the composition of old corrugated containers (OCC) and to manufacture printing and writing papers of over 85% (ISO) brightness by ECF and TCF bleaching from OCC. Fiber length of American old corrugated container (AOCC) was longer than that of Korean old corrugated container (KOCC) in fiber length. The former was composed of unbleached kraft pulp (UKP) of about 80 percentage, the latter about 20 percentage. OCC is feasible for manufacturing of pulps i.e., AOCC is for printing and writing papers and KOCC is for whiteboards, in the aspects of brightness and mechanical properties on the other hand, the cost of manufacturing upgraded papers by OCC is high because of bleaching chemicals. Neverthless, considering various aspects, especially environment, there are many advantages in recycling. In case of the treated AOCC pulp, over 85% (ISO) brightness can be achieved through TCF or ECF bleaching step, while the treated KOCC pulp did not allow high brightness through TCF bleaching. The tensile index of the bleached KOCC pulp was lower than that of the bleached AOCC pulp, but the burst and tear index of KOCC was higher than that of AOCC.

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Optically Active Intermediate from the Degradation of (-)-Laudanosine, a Benzylisoquinoline Alkaloid, with Ethyl Chloroformate

  • Dong-Ung Lee;W. Wiegrebe
    • Bulletin of the Korean Chemical Society
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    • v.12 no.4
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    • pp.373-376
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    • 1991
  • Degradation of (-)-laudanosine, a 1-benzyl-1,2,3,4-tetrahydroisoquinoline alkaloid, with ethyl chloroformate (ECF) afforded an optically active chloro-carbamate as an intermediate. The reason why this intermediate exhibits an optical activity was investigated by comparison with the reactions of some model compounds with ECF. It may be supposed that the chloride group in a hypothetic carbenium ion intermediate stands very closely to the chiral center, so conserving optical activity. However, a neighboring group effect can not be excluded.

Detection of Iron Nanoparticles using Nuclear Magnetic Resonance Relaxometry and Inverse Laplace Transform

  • Kim, Seong Min
    • Journal of Biosystems Engineering
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    • v.39 no.4
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    • pp.345-351
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    • 2014
  • Purpose: Rapid detection of bacteria is very important in agricultural and food industries to prevent many foodborne illnesses. The objective of this study was to develop a portable nuclear magnetic resonance (NMR)-based system to detect foodborne pathogens (E. coli). This study was focused on developing a method to detect low concentrations of magnetic nanoparticles using NMR techniques. Methods: NMR relaxometry was performed to examine the NMR properties of iron nanoparticle mixtures with different concentrations by using a 1 T permanent magnet magnetic resonance imaging system. Exponential curve fitting (ECF) and inverse Laplace transform (ILT) methods were used to estimate the NMR relaxation time constants, $T_1$ and $T_2$, of guar gum solutions with different iron nanoparticle concentrations (0, $10^{-3}$, $10^{-4}$, $10^{-5}$, $10^{-6}$, and $10^{-7}M$). Results: The ECF and ILT methods did not show much difference in these values. Analysis of the NMR relaxation data showed that the ILT method is comparable to the classical ECF method and is more sensitive to the presence of iron nanoparticles. This study also showed that the spin-spin relaxation time constants acquired by a Carr-Purcell-Meiboom-Gill (CPMG) pulse sequence are more useful for determining the concentration of iron nanoparticle solutions comparwith the spin-lattice relaxation time constants acquired by an inversion recovery pulse sequence. Conclusions: We conclude that NMR relaxometry that utilizes CPMG pulse sequence and ILT analysis is more suitable for detecting foodborne pathogens bound to magnetic nanoparticles in agricultural and food products than using inversion recovery pulse sequence and ECF analysis.

Quantitative Relationship between Body Composition and Muscular Strength Measured with the Biodex System 3 (Biodex System3을 사용한 근력측정과 체조성의 양적조건과의 관련성)

  • Lee, Sang-Un;Kim, Yong-Kwon;Sato, Kouki
    • Journal of Korean Physical Therapy Science
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    • v.10 no.2
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    • pp.208-215
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    • 2003
  • This study measured body composition and muscular strength, to examine their relationship, using the Bioelectrical Impedance (IB) method and biodex system3, respectively, in 44 healthy male(20) and female(24) university students. 1. Muscular strength of the upper extremities correlated significantly with fat-free mass(FFM) with $r=.604{\sim}.630$ and intracellular fluid(ICF) with $r=.672{\sim}.668$ in males and FFM with $r=.416{\sim}.552$, ICF with $r=.432{\sim}.564$ and extracellular fluid(ECF) with $r=.429{\sim}.463$ in females. 2. Muscular strength of the lower extremities correlated significantly with FFM with $r=.522{\sim}.785$, ICF with $r=.501{\sim}.739$ and ECF with $r=.498{\sim}.796$ in males and FFM with $r=.642{\sim}.660$, ICF with $r=.627{\sim}.671$ and ECF with $r=.572{\sim}.623$ in females. 3. Muscular strength of the trunk correlated with FFM with $r=.595$, ICF with $r=.627$, ECF with $r=.448$ in males, but did not correlate significantly with body composition in females. These results suggest that total body water(TBW) and ICF may be factors directly associated with muscular strength as well as physical fitness.

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Turbidity Removal of Kaolin in an Electrocoagulation/Flotation Process Using a Mesh-type Aluminum Electrode (메시형 알루미늄 전극을 이용한 전기응집/부상 공정에서 Kaoline의 탁도 제거)

  • Zheng, Chang;Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.26 no.5
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    • pp.563-572
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    • 2017
  • The Electrocoagulation-Flotation (ECF) process has great potential in wastewater treatment. ECF technology is effective in the removal of colloidal particles, oil-water emulsion, organic pollutants such as microalgae, and heavy metals. Numerous studies have been conducted on ECF; however, many of them used a conventional plate-type aluminum anode. In this study, we determined the effect of changing operational parameters such as power supply time, applied current, NaCl concentration, and pH on the turbidity removal efficiency of kaoline. We also determined the effects of different electrolyte types (NaCl, $MgSO_4$, $CaCl_2$, $Na_2SO_4$, and tap water), as well as the differences caused by using a plate-type and mesh-type aluminum anode, on the turbidity removal efficiency. The results showed that the optimal values of ECF time, applied current, NaCl concentration, and pH were 5 min, 0.35 A, 0.4 g/L NaCl in distilled water, and pH 7, respectively. The results also revealed that the turbidity removal efficiency of kaoline in different electrolytes decreased in the following sequence, given the same conductivity: tap water > $CaCl_2$ > $MgSO_4$ > NaCl > $Na_2SO_4$. The turbidity removal efficiency of the mesh-type aluminum anode was significantly greater than the plate-type aluminum anode.

A Study on the Effect of Omibaekchul-san on Postpartum Edema - Comparison with Saenghwa-tang (오미백출산이 분만 후 산모의 부종에 미치는 영향 - 생화탕과 비교하여)

  • Kim, Gun-Hee;Lee, Ji-Hyun;Cho, Han-Baek;Choi, Chang-Min;Kim, Song-Baek
    • The Journal of Korean Obstetrics and Gynecology
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    • v.28 no.2
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    • pp.91-108
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    • 2015
  • Objectives : The aim of this study was to investigate the effect of Omibaekchul-san on postpartum edema in women hospitalized at korean medical postpartum care center in comparison with Saenghwa-tang. Methods : The body composition data was collected from 102 women, who took postpartum care in postpartum care center attached to Won-kwang University Jeonju Korean Medical Hospital, from March 2012 to July 2013. The data was analyzed by Body Composition Analyzer (Inbody 720). Specifically the data was composed of the Extra Cellular Fluid/Total Body Fluid (ECF/TBF), Total Body Water (TBW), Intra Cellular Water (ICW), Extra Cellular Water (ECW), Body Weight, Body Mass Index (BMI), Waist Hip Ratio (WHR), and the ECF/TBF of each body parts such as the upperlimb, lowerlimb and trunk. The body composition was measured twice during 2~8.5 days from childbirth and once again after 7~13.5 days from childbirth by Body Composition Analyzer. Results : The Omibaekchul-san -treated group showed a significant decrease of ECF/TBF, ECW, TBF, Body weight, BMI, ECF/TBF of each body parts and increase of WHR in comparison with the data of the Saenghwa-tang-treated group. In two groups, only the change of ICW was unsignificant. Conclusions : Statistically this study suggests that the Omibaekchul-san will help the quality of life of women who are in postpartum edema.

Internal Changes of Blood Compartment and Heat Distribution in Swamp Buffaloes under Hot Conditions : Comparative Study of Thermo-Regulation in Buffaloes and Friesian Cows

  • Koga, A.;Kurata, K.;Ohata, K.;Nakajima, M.;Hirose, H.;Furukawa, R.;Kanai, Y.;Chikamune, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.6
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    • pp.886-890
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    • 1999
  • From previous studies, there is a strong possibility in buffaloes that the marked increase in blood volume (BV) under hot conditions contributes to heat transportation from the rectum to the skin. The present study was done to clarify changes with environmental temperature on water-shift between blood and extracellular fluid (ECF), heat distribution between the rectum and the skin, and blood flow rates (BFR) at the hind legs (reflecting the skin surface). Four buffaloes and four Friesian cows were successively exposed to three different temperatures of $20^{\circ}C$, $30^{\circ}C$ and $35^{\circ}C$. BV and ECF volume were measured with Evans' blue and sodium-thiocyanate dilution methods, respectively. Rectal and subcutaneous (as the skin) temperatures were measured by copper-constantan thermocouples. BFR were measured by a supersonic blood flow meter. With an increase in environmental temperature, skin temperature in buffaloes increased significantly than cows, but rectal temperature was not significantly different between two species. BV, especially plasma compartment, increased significantly in only buffaloes, while ECF volume did not change in both species. BFR increased significantly in buffaloes, but not in cows. From these results, the increased of BV may be caused by water flowing from ECF compartment. The water-shift may induce the increase of BFR and skin temperature. It is suggested in the present study that internal changes of blood compartment in buffaloes contribute to transfer of heat to the skin surface.

Water and Sodium Balance of Body Fluid (체액의 수분 및 나트륨 균형)

  • Kim, Ji-Hong
    • Childhood Kidney Diseases
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    • v.14 no.2
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    • pp.111-119
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    • 2010
  • The maintenance of the osmolality of body fluids within a very narrow physiologic range is possible by water balance mechanisms that control the intake and excretion of water. Main factors of this process are the thirst and antidiuretic hormon arginine vasopressin (AVP), secretion regulated by osmoreceptors in the hypothalamus. Body water is the primary determinant of the osmolality of the extracellular fluid (ECF), disorders of body water homeostasis can be divided into hypo-osmolar disorders, in which there is an excess of body water relative to body solute, and hyperosmolar disorders, in which there is a deficiency of body water relative to body solute. The sodium is the predominant cation in ECF and the volume of ECF is directly proportional to the content of sodium in the body. Disorders of sodium balance, therefore, may be viewed as disorders of ECF volume. This reviews addresses the regulatory mechanisms underlying water and sodium metabolism, the two major determinants of body fluid homeostasis for a good understanding of the pathophysiology and proper management of disorders with disruption of water and sodium balance.

Bioelectrical Impedance Analysis at Popliteal Regions of Human Body using BIMS

  • Kim, J.H.;Kim, S.S.;Kim, S.H.;Baik, S.W.;Jeon, G.R.
    • Journal of Sensor Science and Technology
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    • v.25 no.1
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    • pp.1-7
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    • 2016
  • Bioelectrical impedance (BI) at popliteal regions was measured using a bioelectrical impedance measurement system (BIMS), which employs the multi-frequency and the two-electrode method. Experiments were performed as follows. First, a constant AC current of $800{\mu}A$ was applied to the popliteal regions (left and right) and the BI was measured at eight different frequencies from 10 to 500 kHz. When the applied frequency greater than 50 kHz was applied to human's popliteal regions, the BI was decreased significantly. Logarithmic plot of impedance vs. frequency indicated two different mechanisms in the impedance phenomena before and after 50 kHz. Second, the relationship between resistance and reactance was obtained with respect to the applied frequency using BI (resistance and reactance) acquired from the popliteal regions. The phase angle (PA) was found to be strongly dependent on frequency. At 50 kHz, the PA at the right popliteal region was $7.8^{\circ}$ slightly larger than $7.6^{\circ}$ at the left popliteal region. Third, BI values of extracellular fluid (ECF) and intracellular fluid (ICF) were calculated using BIMS. At 10 kHz, the BI values of ECF at the left and right popliteal regions were $1664.14{\Omega}$ and $1614.08{\Omega}$, respectively. The BI values of ECF and ICF decreased sharply in the frequency range of 10 to 50 kHz, and gradually decreased up to 500 kHz. Logarithmic plot of BI vs. frequency shows that the BI of ICF decreased noticeably at high frequency above 300 kHz because of a large decrease in the capacitance of the cell membrane.