• Title/Summary/Keyword: Heat retention

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On the manufacturing of WPC (Wood Plastic Composites) with Heat-Catalyst Polymerization (I) - On the characteristics of composites made from monomer Methyl MethacryIate and several commercial woods in Korea (가열(加熱)·촉매중합법(觸媒重合法)에 의한 목재(木材)·고분자복합체(高分子複合體) 제조(製造)(I) - MMA에 의한 한국산(韓國産) 주요목재(主要木材)의 복합체특성(複合體特性))

  • Cho, Nam-Seok;Jo, Jae-Myeong;Ahn, Won-Yong
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.3
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    • pp.3-16
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    • 1974
  • One of the disadvantages of. wood and wood products is their hydroscopicity or dimensional instability. This is responsible for the loss of green volume of lumber as seasoning degrade. Dimensional stabilization is needed to substantially reduce seasoning defects and degrades and for increasing the serviceability of wood products. Recently, considerable world-wide attention has been drawn to the so-called Wood-Plastic Composites by irradiation-and heat-catalyst-polymerization methods and many research and developmental works have been reported. Wood-Plastic Composites are the new products having the superior mechanical and physical properties and the combinated characteristics of wood and plastic. The purpose of this experiment was to obtain the basic data for the improvement of wooden materials by manufacturing WPC. The species examined were Mulpurae-Namoo (Fraxinus, rhynchophylla), Sea-Namoo (Carpinus laxiflora), Cheungcheung-Namoo (Cornus controversa), Gorosae-Namoo (Acermono), Karae-Namoo(Juglans mandshurica) and Sanbud-Namoo (Prunus sargentii), used as blocks of type A ($3{\times}3{\times}40cm$) and type B ($5{\times}5{\times}60cm$), and were conditioned to about 10~11% moisture content before impregnation in materials humidity control room. Methyl methacrylate (MMA) as monomer and benzoyl peroxide (BPO) as initiator are used. The monomer containing BPO was impregnated into wood pieces in the vacuum system. After impregnation, the treated samples were polymerized with heat-catalyst methods. The immersed weights of monomer in woods are directly proportionated to the impregnation times. Monomer impregnation properties of Cheungcheung-Namoo, Mulpurae-Namoo and Seo-Namoo are relatively good, but in Karae-Namoo, it is very difficult to impregnate the monomer MMA. Fig. 3 shows the linear relation between polymer retentions in wood and polymerization times; that is, the polymer loadings are increasing with polymerization times. Furthermore species, moisture content, specific gravity and anatomical or conductible structure of wood, bulking solvents and monomers etc have effects on both of impregnation of monomer and polymer retention. Physical properties of treated materials are shown in table 3. Increasing rates of specific gravity are ranged 3 to 24% and volume swelling 3 to 10%. ASE is 20 to 46%, AE 14 to 50% and RWA 18 to 40%. Especially, the ASE in relation to absorption of liquid water increases approximately with increase of polymer content, although the bulking effect of the polymerization of monomer may also be influential. WPCs from Mulpurae-Namoo and Cheungcheung-Namoo have high dimensional stability, while its of Karae-Namoo and Seo-Namoo are-very low. Table 4 shows the mechanical properties of WPCs from 6 species. With its specific gravity and polymer loading increase, all mechanical properties are on the increase. Increasing rate of bending strength is 10 to 40%, compression strength 25 to 70%, ;impact bending absorbed energy 4 to 74% and tensile strength 18 to 56%. Mulpurae-Namoo and Cheungcheung-Namoo with high polymer content have considerable high increasing rate of strengths. But incase of Karae-Namoo with inferior monomer impregnation it is very low. Polymer retention in cell wall is 0.32 to 0.70%. Most of the polymer is accumulated in cell lumen. Effective. of polymer retention is 58.59% for Mulpurae-Namoo, 26.27% for Seo-Namoo, 47.98% for Cheungcheung-Namoo, 25.64% for Korosae-Namoo, 9.96% for Karae-Namoo and 25.84% for Sanbud-Namoo.

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Antimicrobial Activity of Gluten Hydrolysate with Asp. saitoi Protease (밀 단백 효소 가수분해물의 항균활성)

  • Lee, Sang-Duk;Joo, Jeong-Hyeon;Lee, Gyu-Hee;Lee, K.T.;Oh, Man-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.5
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    • pp.745-751
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    • 2003
  • This study was carried out to investigate whether peptide produced from wheat protein by enzyme hydrolysis can be used as a natural antimicrobial agent. Antimicrobial peptide was obtained from wheat protein hydrolyzed by 7 of pretense. The produced antimicrobial peptide was purified through ultrafiltration, membrane filtration and HPLC and molecular weight and amino acid sequence of the purified antimicrobial peptide were determined. Among hydrolysate produced from wheat protein by 7 of protease, antimicrobial activity was observed for the peptide obtained from Asp. saito protease. The Asp. saito protease did produce antimicrobial hydrolysate showing the highest antimicrobial activity at reaction condition of 37$^{\circ}C$ and pH 6.0, but not at reaction condition above 5$0^{\circ}C$. Wheat protein hydrolysate was fractionated by membrane filtration and showed antimicrobial activity between molecular weight 1,000~3,000. The antimicrobial activity fraction obtained by membrane filtration was separated through HPLC and showed antimicrobial activity in the peak of retention time 31.1~31.8 min. We could convince this hydrolysate as heat-stable peptide since antimicrobial activity was maintained after treated with heat for 15 min at 121$^{\circ}C$. Molecular weight of antimicrobial peptide identified by MALDI-mass was 1,633. Amino acid sequence of antimicrobial peptide was cysteine, glycine, prolin, prolin, prolin, valine, valine, alanine, alanine and arginine.

Literature Review on Parkinson's Disease in Oriental Medicine (파킨슨병의 한의학적 고찰 -병인병리(病因病理)와 침구요법(鍼灸療法)을 중심으로-)

  • Park, Sang-min;Lee, Sang-hoon;Yin, Chang-shik;Kang, Mi-kyeong;Chang, Dae-il;Kang, Sung-keel;Lee, Yun-ho
    • Journal of Acupuncture Research
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    • v.21 no.1
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    • pp.202-210
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    • 2004
  • Objective: In order to find oriental medical therapies on Parkinson's disease and to make a fundamental basis for clinical application, this study was performed. Methods: We reviewed 35 kinds of the ancient and modern text, and related articles. Results: Parkinson's disease is an extrapyramidal disease characterized by akinesia, tremor at rest, rigidity, and slowness of movement. In old oriental medical text, Parkinson's disease is described as Jinjeon(振顫), Chi, Gyeong (痙), Gyejong, Ryeon(攣) and Pyeongo(偏枯), Tantan, Jungbu(中腑症) of Jungpung(中風). According to the text, major pathological causes were Wind(風), Fire(火), Phlegm(痰), and Blood stasis(瘀血). And Parkinson's disease can be classified into four clinical types as liver & kidney yin-deficiency, qi & blood deficiency, retention of phlegm-heat, and qi-stagnation & blood stasis. Standardized acupuncture points are GV20, GB20, GV14 on head, CV12, ST25 on abdomen, GV26, ST7, GB1, S14, LI20 on face, LI4, LI11, TE5, SI3, HT3, LI15, SI6 on upper extremity, and ST36, GB34, SP6, LR3, KI1, GB30, BL40 on lower extremity. Other methods, such as scalp acupuncture, electro-acupuncture, and herb-acupuncture, can be applied to treat Parkinson's disease. Conclusions: We find out that there are oriental medical concepts related with Parkinson's disease such as Jinjeon(振顫), Chi, Gyeong (痙), Gyejong, Ryeon(攣) and Pyeongo(偏枯), Tantan, Jungbu(中腑症) of Jungpung(中風), of which major causes are Wind(風), Fire(火), Phlegm(痰), and Blood stasis(瘀血). We can also apply many effective acupuncture points and acupuncture therapies according to differential diagnosis, for example, liver & kidney yin-deficiency. qi & blood deficiency, retention of phlegm-heat, and qi-stagnation & blood stasis.

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Physicochemical Properties of Xylooligosaccharide as Food Material (식품소재로서의 Xylooligosaccharide의 물리화학적 특성)

  • Park, Youn-Je;Lee, Ji-Wan;Lee, Chang-Seung;Rhew, Bo-Kyung;Yang, Chang-Kun
    • Korean Journal of Food Science and Technology
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    • v.33 no.1
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    • pp.19-23
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    • 2001
  • Physicochemical properties including viscosity, temperature and pH stability, color turbidity and moisture retention power of xylooligosaccharide(XO) as food material were investigated to apply to food process. The viscosity of 70 bx XO was 930 cP at $20^{\circ}C$ and 90 cP at $60^{\circ}C$, which was higher than that of sugar but lower than that of other oligosacchrides. XO remained stable after heat treatment for 1hr at $100^{\circ}C$ and pH 2.5 to 8.0 indicating excellent heat and pH stability. The pH of XO was measured $5.0{\pm}0.1$ and the color turbidvity of XO was very low at pH $2.5{\sim}4.0$. The color turbidity of XO increased as pH increased, but it was not high enough to affect food process. When heated with 1% glycine the color turbidity of XO was very low and changed little with pH changes. To measure moisture retention power XO was stored at $25^{\circ}C$ and 75% relative humidity for 71 day. XO retained more than 95% of the original weight; whereas sugar lost 28%. These results suggest that XO has useful physicochemical properties for various food process to improve the functionality of food.

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Application and Antimicrobial Activities of Casein Hydrolysates Treated with Asp.oryzae Protease (Casein 효소 가수분해물의 항균 활성과 그 응용)

  • Lee Hye-Jin;Yi Sang-Duk;Oh Man-Jin
    • Food Science and Preservation
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    • v.13 no.1
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    • pp.88-94
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    • 2006
  • This study was carried out to produce antimicrobial peptides from casein using various proteases. To examine whether the hydrolysis of casein would produce antimicrobial substance and the application as natural antimicrobial material, casein was hydrolyzed by five different proteases. The casein hydrolysate was fractionated with regenerated membrane filter (molecular weight cut-off 30,000 10,000 and 3,000) and antimicrobial activity was measured for each fraction. Antimicrobial activity appeared great in the fraction below 3,000 molecular weight The fraction was re-fractionated by high performance liquid chromatography and substance of main peak (retention time: 13.2 min) collected was used as a sample to measure antimicrobial activity. Among the casein hydrolysates produced by protease, antimicrobial activity was observed the greatest in hydrolysate treated with Aspergillus oryzae protease. The minimum inhibition concentrations of the Asp. oryzae protease hydrolysate were 1.0-1.5 mg/mL. This hydrolysate was a heat stable peptide since antimicrobial activity was maintained after treating with heat for 20 min at $121^{\circ}C$.

Effects of Protein Supplement Sources on Digestibility of Nutrients, Balance of Nitrogen and Energy in Goats and Their In Situ Degradability in Cattle

  • Khan, M.J.;Nishida, T.;Miyashige, T.;Hodate, K.;Abe, H.;Kawakita, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.6
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    • pp.673-679
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    • 1998
  • The experiment was conducted to determine in situ rumen degradability of soybean meal (SM), fish meal (FM), sesame cake (SC) and Italian ryegrass hay (IRGH) and the effect of supplementing the above protein meals to IRGH on digestibility and balance of nutrients in three Saanen goats. For measuring the degradability, nylon bags containing each meal were incubated in the rumen of one fistulated dry cow for 3, 6, 12, 24, 36, and 48 hrs. Degradability revealed that SM protein was highly degradable in the rumen (99.1%), while FM protein was less degradable (76.8%) with SC protein being intermediate (91.2%) at 48 hrs of incubation (p < 0.01). Degradation rate of the potentially degradable fraction was estimated to be 12.12, 5.88 and 5.88%/hr for SM, FM and SC, respectively. In the metabolism trial, all goats were offered daily 900 g IRGH and one of the supplements, SM (100 g), FM (75 g) or SC (100 g). Intake of DM, OM, CP and GE was similar among diets. However, digestibility of OM for SC diet was significantly lower than that for diets supplemented with FM and SM (p < 0.10). Nitrogen (N) excreted in faeces (p < 0.05) and in urine (p < 0.10) was, respectively, higher and lower for SC diet than that for the other two diets. The same tendency was observed in energy losses in faeces (p < 0.10) and in urine (p < 0.05). There was no difference in energy loss in methane or in heat production among diets. Consequently, no significant difference was observed in N retention (2.13, 0.42 and -0.11 g/day for FM, SC and SM diet, respectively) or in energy retention (-1.49, -2.14 and -2.70 MJ/day for FM, SM and SC diet, respectively). These results showed that protein supplements affected the digestion of diets based on grass hay with 7.45% CP in DM in goats, although there was no significant influence on N or energy retention.

Clinical Study on 1 Case of patient with Urinary Retention (요폐환자(尿閉患者) 1례(例)에 대한 임상적(臨床的) 고찰(考察))

  • Kim, Jae-Hyeng;Cho, Chung-Sik;Kim, Chul-Jung
    • Journal of Haehwa Medicine
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    • v.14 no.1
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    • pp.43-49
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    • 2005
  • One case of patient with urinary retention was reported in this clinical study. After the study, the results were as follows: 1. Anulesis belongs to l$\acute{o}$ng-bi(癃閉) in oriental medicine and the patient of this case belongs to chronic anulesis. 2. The patient of this case was thought as broke out anuresis by vesical nerve palsy of diabetic bladder pathy and sequela of stroke, and ischuria of long lie down 3. The patient of this case changeable process is supposed to urinary frequency, 'bi(閉)', 'l$\acute{o}$ong(癃)', urinary incontinence and urinary frequency. 4. First time of drug treatment is GAMIPHALJENG-SAN(ji$\bar{a}$-w$\grave{e}$i-b$\bar{a}$-h$\bar{e}$ng-s$\check{a}$n) by oral administration that action of alleviate a fever, water utilization and metaphase, convalescence time of drug treatment is PHALMIWANGAMI (b$\bar{a}$-w$\grave{e}$i-w$\acute{a}$n-ji$\bar{a}$-w$\grave{e}$i), YIKLUENG-TANG(yi-ling-t$\bar{a}$ng), CHUKYOO-TANG(s$\grave{u}$-ni$\grave{a}$o-t$\bar{a}$ng) that action of recreation. 5. Accupuncture treatment is s$\bar{a}$n-x$\bar{i}$ng-xuw$\acute{e}$, zw$\acute{u}$-s$\bar{a}$n-li, qi-h$\check{a}$i, gu$\bar{a}$n-yu$\acute{a}$n, zh$\bar{o}$ng-ji by mild supplementing and reducing manipulation of needle and heat accupuncture is qi-h$\check{a}$i, gu$\bar{a}$n-yu$\acute{a}$n, zh$\bar{o}$ng-ji-xu$\acute{e}$. 6. The other treatment is a sitz bath that prevent of urinary tract infection, and relieve of initial acute auresis by using of urethral catheterization.

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A Review on Measurement Techniques and Constitutive Models of Suction in Unsaturated Bentonite Buffer (불포화 벤토나이트 완충재의 수분흡입력 측정기술 및 구성모델 고찰)

  • Lee, Jae Owan;Yoon, Seok;Kim, Geon Young
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.3
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    • pp.329-338
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    • 2019
  • Suction of unsaturated bentonite buffers is a very important input parameter for hydro-mechanical performance assessment and design of an engineered barrier system. This study analyzed suction measurement techniques and constitutive models of unsaturated porous media reported in the literature, and suggested suction measurement techniques and constitutive models suitable for bentonite buffer in an HLW repository. The literature review showed the suction of bentonite buffer to be much higher than that of soil, as measured by total suction including matric suction and osmotic suction. The measurement methods (RH-Cell, RH-Cell/Sensor) using a relative humidity sensor were suitable for suction measurement of the bentonite buffer; the RH-Cell /Sensor method was more preferred in consideration of the temperature change due to radioactive decay heat and measurement time. Various water retention models of bentonite buffers have been proposed through experiments, but the van Genuchten model is mainly used as a constitutive model of hydro-mechanical performance assessment of unsaturated buffers. The water characteristic curve of bentonite buffers showed different tendencies according to bentonite type, dry density, temperature, salinity, sample state and hysteresis. Selection of water retention models and determination of model input parameters should consider the effects of these controlling factors so as to improve overall reliability.

The Study on Korean Medical Pattern Differentiation of Sleep-Wake Disorders by DSM-V Classification (DSM-V 분류에 따른 수면-각성장애의 한의학적 변증 연구)

  • Na, Il Doo;Park, Mi Sun;Kim, Yeong Mok
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.31 no.2
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    • pp.83-93
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    • 2017
  • This study covers pattern differentiation based on Korean medical references, research trend and modern clinical applications about Sleep-Wake disorders of Diagnostic and Statistical Manual of Mental Disorders(DSM-V) published by American Psychiatric Association. Insomnia disorder is mostly caused by yin deficiency of liver-kidney or liver qi depression and main patterns are heart-kidney non-interaction, deficiency-excess complex pattern containing phlegm-heat due to qi stagnation and blood stasis. Hypersomnolence disorder is more due to yang deficiency rather than yin deficiency and it's major pattern is spleen-kidney yang deficiency. Cataplexy is main feature in narcolepsy and corresponds to depressive psychosis or fainting in terms of Korean Medicine and narcolepsy is assumed to be relevant to liver wind. Breathing-related sleep disorders are related with phlegm-fluid retention brought on spleen deficiency with dampness encumbrance. Pattern of circadian rhythm sleep-wake disorders is combined with yin deficiency of liver-kidney or liver qi depression of insomnia disorder and spleen-kidney yang deficiency or dampness-phlegm of hypersomnolence disorder. Yin deficiency with effulgent fire brought on drugs or alcohol is one of main patterns of substance/medication-induced sleep disorder and combined patterns with yin deficiency of liver-kidney and blood stasis or dampness-phlegm-heat are mostly applied clinically. This study drew major and frequently applied patterns of sleep-wake disorders based on Koran medical literature and modern clinical applications. And that can be the groundwork for the task ahead like clinical practice guideline of sleep-wake disorders containing pattern differentiation, diagnosis and prescriptions.

A Feasibility Study for Renewable Energy from Sewage Sludge Biogas (하수슬러지 Biogas의 신재생에너지화 타당성 연구)

  • Kang, Ho;Lee, Hye Mi;Cho, Sang Sun;Park, Sun Uk;Jeong, Ji Hyun
    • Journal of Korean Society on Water Environment
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    • v.26 no.5
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    • pp.754-760
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    • 2010
  • This study was carried out not only to evaluate optimal operating condition to increase biogas production, but also to estimate feasibility of renewable energy from anaerobic digester of sewage sludge. Semi- continuous Fed and Mixed Reactors (SCFMRs) were operated in various condition to quantify the reactor variables. The result of SCFMR operation showed that the biogas productivity and total volatile solids (TVS) removal of total solids (TS) 4% reactor at hydraulic retention time (HRT) 20 days with Organic Loading Rate (OLR) of $1.45kg/m^3-d$ were $0.39m^3/m^3-d$ and 26.7%, respectively which was two times higher than that of TS 2.5% reactor. Consequently the daily biogas production of $20,000m^3$ would be possible from the total volume of $52,000m^3$ of anaerobic digesters of the municipal wastewater treatment plant in D city. In feasibility study for the Biogas utilization, combined heat and power system (CHP) and CNG gasification were examined. In case of CHP, the withdrawal period of capital cost for gas-engine (GE) and micro gas-turbine (MGT) were 7.7 years and 9.1 years respectively. biogas utilization as Clean Natural Gas (CNG) shows lower capital cost and higher profit than that of CHP system. CNG gasificaion after biogas purification is likely the best alternative for Biogas utilization which have more economic potential than CHP system. The withdrawal period of capital cost appeared to be 2.3 years.