• Title/Summary/Keyword: Absorption Properties

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Characteristic Properties of Fucoidan Sulfate Purified from Gompi, Ecklonia stolonifera (곰피에서 정제한 Fucoidan Sulfate의 특성)

  • Lee, Hong-Soo;Jin, Sung-Hyun;Kim, Hee-Sook;Ryu, Byung-Ho
    • Korean Journal of Food Science and Technology
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    • v.27 no.5
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    • pp.716-723
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    • 1995
  • The fucoidan purified from Korean brown seaweed, Ecklonia stolonifera was characterized on molecular structure and blood anticoagulant activities. Extraction was conducted at $100^{\circ}C$ with water and repeated twice. The crude fucodian was 151.1g out of 20.0 kg of Ecklonia stolonifera. The Fucoidan-1, which was purified from crude fucoidan using calcium chloride and cetyl pyridium chloride (CPC), was 35.2% against crude fucoidan. Fucoidan-5 was obtained approximately 28.1% from Fucoidan-1 through DEAE-Toyopearl 650 M ion-exchange column chromatography and showed one band by cellulose acetate electrophoresis. The molecular weight of Fucoidan-5 was estimated to be about 21,000∼23,000 dalton by Sephacryl S-300 gel filtration chromatography. Fucoidan-5 consists of 35.7% of fucose and 4.3% of galactose and the molar ratio of fucose and sulfate was about one to one. IR spectrum of Fucoidan-5 showed absorption at $1240\;cm^{-1}\;and\;850\;cm^{-1}$ and specific rotation value, $[\alpha]$, was $[\alpha]$. These results suggests that the sulfate maybe bind at $C_{4}$ carbon on ${\alpha}-L-fucose$. Gas chromatograph of methyl alditol acetate revealed that Fucoidan-5 is a fucose containing sulfated polysaccharide with $({\alpha}l-2)\;or\;({\alpha}l-2)$ glycosidic linkage. Anti-thrombin activity of the Fucoidan-5 was estimated as 1.4 time stronger than heparin. From above results, the purification methods using CPC and ion exchange chromatography is effective tools for obtaining highly purified fucoidan from Gompi, Ecklonia stolonifera.

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Uptake Properties of Germanium to Vegetable Plants and Its Effect on Seed Germination and on Early Stage Growth (채소종자 발아와 유묘생장에 미치는 유기 또는 무기게르마늄의 효과 및 흡수특성)

  • Han, Myung-Ja;Kim, Sung-Un;Seo, Dong-Cheol;Cheong, Yong-Hwa;Lee, Do-Jin;Park, Moon-Su;Rim, Yo-Sup;Sohn, Bo-Kyoon;Heo, Jong-Soo;Cho, Ju-Sik
    • Korean Journal of Environmental Agriculture
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    • v.26 no.3
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    • pp.217-222
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    • 2007
  • To investigate effects of inorganic $(GeO_2)$ and organic (Ge-132) germanium (Ge) on seed germination and on early stage growth of plane and the uptake characteristics, various concentrations (0, 10, 25, 50, 100 mg $L^{-1}$) of Ge to popular vegetables such as leaf mustard, chinese cabbage and pak-choi, respectively, were treated. On seed germination, no significant effect was observed in both inorganic and organic Ge treatments except 100 mg $L^{-1}$ treatment of inorganic Ge. Exogenous inorganic Ge ($10{\sim}100$ mg $L^{-1}$ treatments significantly inhibited the early root elongation growth of all plants. However, slight enhancement of early shoot elongation was detected in low concentrations (10 and 25 mg $L^{-1}$) of Ge in the leaf mustard and chinese cabbage plants. Organic Ge treatments significantly stimulated the 개ot and shoot growth at the 10, 25 and 50 mg $L^{-1}$ treatments. Ge was accumulated linearly in the vegetables as both inorganic and organic Ge concentrations were increased. Interestingly, total contents of Ge in plants with Ge-132 treatments were $2\sim4.5$ times more than those with inorganic Ge treatments in all concentrations. At 25 mg $L^{-1}$ treatment of Ge, contents of Ge in vegetables are following: in leaf mustard, inorganic Ge: 0.37 mg $g^{-1}dw$ and organic Ge: 1.47 mg $g^{-1}dw;$ in the chinese cabbage, inorganic Ge: 0.4 mg $g^{-1}dw$ and organic Ge: 0.86 mg $g^{-1}dw;$ in the pak-choi, inorganic Ge: 0.33 mg $g^{-1}dw$ and organic Ge: 0.70 mg $g^{-1}dw$, respectively. These results showed organic Ge is much better on early stage seedling growth and on germanium accumulation of vegetables than inorganic Ge.

Properties of Dietary Fiber Extract from Rice Bran and Application in Bread-making (미강에서 추출한 식이섬유추출물의 특성 및 제빵에의 응용)

  • Kim, Young-Soo;Ha, Tae-Youl;Lee, Sang-Hyo;Lee, Hyun-Yu
    • Korean Journal of Food Science and Technology
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    • v.29 no.3
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    • pp.502-508
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    • 1997
  • Rice bran dietary fiber extract, which was obtained after termamyl treatment of defatted rice bran contained $27.3{\sim}30.5%$ protein, $49.7{\sim}54.1%$ insoluble dietary fiber, and $1.9{\sim}2.7%$ soluble dietary fiber. Extrusion decreased the insoluble dietary fiber content but increased the soluble dietary fiber content, while roasting did not. Influence those content. Each mineral element content was depended upon heat processing method. Extrusion increased the water binding capacity and L value, while roasting reduced the water binding capacity and L value. Scanning electron microscopy showed damaged cell walls for extruded sample compared to roasted one which had fully collapsed cell walls. The increase of water absorption, developing time, and stability and the of MTI of wheat flour-dietary fiber extract composites with addition of dietary fiber extract were observed by Farinograph. Rice bran dietary fiber extract had an effect on the bread making resulting in increase of bread weight and color of crumb and crust, and decrease of bread volume and texture. As a result of sensory evaluation, appearance, texture, overall acceptability were significantly different from control but flavor and taste were not different significantly up to 6% level. Heat treated samples had differences in mean values, but not significant differences statistically.

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2013 (설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.12
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    • pp.605-619
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    • 2014
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

Crystal Growth of $Cr:Al_2O_3$ and $Ti:Al_2O_3$ by Czochralski Technique (용액인상법에 의한 $Cr:Al_2O_3$$Ti:Al_2O_3$ 단결정 육성)

  • Yu, Yeong-Mun;Lee, Yeong-Guk;Park, Ro-Hak
    • Korean Journal of Crystallography
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    • v.6 no.1
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    • pp.1-13
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    • 1995
  • Cr:A12O3 and Ti:A12O3 single crystals were grown by Czochralski method, and the effects of crystal growth parameters such as pulling rate, rotation rate, dopant and growth atmosphere on crystal quality were investigated. And spectroscopic properties including lasing efficiency were also measured. Single crystals, sized of 20mm in diameter and 100-135mm in length, were successfully grown from the seed of <001> direction. With the doping level of 0.5w/o Cr2O3, pulling rate 2.0mm/hr, rotation rate of 30rpm and inert atmosphere by nitrogen gas, high quality crystals of Cr:A12O3 were grown. While in case of Ti:A12O3 crystals, high quality crystals were grown under the conditions of the doping level of 0.25w/o TiO2, pulling rate of 1.5mm/hr, rotation rate of 30rpm and reducing atmosphere by hydrogen - nitrogen mixed gas. It was confirmed that Cr3+ ion which maintains its ionoc valence during growth easily de-bubbled than Ti4+ ion which changes its valence, Fe3+ ion also has do-bubbling effect to Ti:A12O3 crystal and the reducing atmosphere by 90% N2 - 10% H2 mixed gas gave effective result on the changing of Ti4+ to Ti3+ and de-bubbling. As a result of spectroscopic measurements of Cr:A12O3 crystal, 4A2 →4F2 and 4F1 absorption transitions and E →4A2(R1) and 2A →4A2(R2) fluorenscence transitions were confirmed. And it was measured that wavelengths of laser R1 and R2 transitions were 696±5nm and 692±5nm respectively, line width of these transitions were 12A, and life-time of fluorenscence was 152μsec. In case of Ti:A12O3 crystals, it was confirmed that absortion transition of 4T2→4E and fluorescence transition of 4E→4T2 with wide range of 650-1050nm was occured. And 147μsec of life-time of fluorescence, 125.4 of figure of merit and 9% of laser efficience were also measured.

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Recent Progress in Air Conditioning and Refrigeration Research - A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2004 and 2005 - (공기조화, 냉동 분야의 최근 연구 동향 -2004년 및 2005년 학회지 논문에 대한 종합적 고찰-)

  • Choi, Yong-Don;Kang, Yong-Tae;Kim, Nae-Hyun;Kim, Man-Hoe;Park, Kyoung-Kuhn;Park, Byung-Yoon;Park, Jin-Chul;Hong, Hi-Ki
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.19 no.1
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    • pp.94-131
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    • 2007
  • A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

Effect of Storage Temperature and Humidity on Water Vapor Permeability of Al-foil Laminate Paper (저장온도(貯藏溫度) 및 습도(濕度)가 알루미늄박(箔) 적층지(積層紙)의 수분투과율(水分透過率)에 미치는 영향(影響))

  • Park, Kil-Dong;Choi, Jin-Ho;Sung, Hyun-Soon;Hong, Soon-Keun
    • Korean Journal of Food Science and Technology
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    • v.13 no.4
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    • pp.314-318
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    • 1981
  • In order to improve the storage stability of spray and freeze dried red ginseng extract powder packed in a bottle, the water vapor permeability of Al-foil laminate paper used for cap closure and shelf life of those products on various storage temperatures and relative humidities were investigated. The thickness of the laminate paper was $93{\pm}3\:{\mu}m$ and its physical properties were equal to standard of ASTM (B-377-66) The absorption rate of the freeze dried powder was 2-6 times greater than that of the spray dried powder at $37^{\circ}C$. Therefore it was considered that the laminate could be used for cap closures for the spray dried powder but unsuitable for the freeze dried powder. The shelf life of the spray dried powder was longer than that of the freeze-dried powder at $37^{\circ}C$.

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Effect of Application Time and Rate of Mixed Expeller Cake on Soil Environment and Rice Quality (혼합유박 시용량 및 시용시기가 토양환경과 미질에 미치는 영향)

  • Yang, Chang-Hyu;Yoo, Chul-Hyun;Kim, Byeong-Su;Park, Woo-Kyun;Kim, Jae-Duk;Jung, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.2
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    • pp.103-111
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    • 2008
  • This study was carried out to investigate the optimal application rate and time of mixed expeller cake (MEC) for the replacement of chemical fertilizer. Dongjin-1, as cultivated rice was used at Fluvio-marine deposit in Honam plain paddy field. Soil chemical properties were improved by the application of MEC. Contents of total nitrogen and organic matter were higher in 70%, 100% plots of basal dressing than standard fertilizer application (SFA) plot. Cation exchangeable capacity was highly increased in 70% plot of basal dressing. Also, the content of organic matter in soil was increased with MEC application. Cation exchangeable capacity, total nitrogen and available phosphate were decreased according to late application time. The content of inorganic nitrogen in soil showed high tendency at more application rate of MEC, and nitrogen mineralization at harvest season have finished in 50%, 70% plots of basal dressing. The content of inorganic nitrogen in soil was increased according to late application time, however it was decreased in the late period of growth. Leaf color value became darker with increased application rate of MEC. Leaf color was dark green in MEC application plots at panicle formation stage, on the other hand, it was light green in 50%, 70% plots of basal dressing at heading stage. SPAD reading value of leaf-color was high during the whole growth stage in MEC application plots. More application rate of MEC showed higher tendency of fertilizer nitrogen absorption. Nitrogen use efficiency was the highest in 70% plot of basal dressing. Absorbed amount of fertilized nitrogen was increased in 10~15days before transplanting and nitrogen use efficiency was high according to the late application time. The ratio of perfect kernel and the content of protein on hulled rice showed high tendency at the less application rate of MEC. The ratio of head rice on milled rice showed high tendency at the less application rate of MEC. Rice yield increased 4% in 100% and 70% plots of basal dressing compare with SFA ($5.18Mg\;ha^{-1}$) plot respectively. Ear and culm length of rice were long according to the late application time, while the numbers of spikelet and ear were increased and the percentage of ripened grain was decreased. Rice yield was increased 2~5% in all MEC application plots compared to SFA plot and especially, increased 10~15days before transplanting in application plots. The optimal application rate and time of MEC on normal paddy field in plain were concluded that 70% basal dressing and 10~15days before transplanting

Pharmacokinetics of oxolinic acid in cultured olive flounder Paralichthys olivaceus by oral administration, injection and dipping (Oxolinic acid의 경구투여, 주사 및 약욕에 따른 넙치, Paralichthys olivaceus 체내 약물동태학적 특성)

  • Jung, Sung-Hee;Choi, Dong-Lim;Kim, Jin-Woo;Jo, Mi-Ra;Jee, Bo-Young;Seo, Jung-Soo
    • Journal of fish pathology
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    • v.22 no.2
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    • pp.125-135
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    • 2009
  • The pharmacokinetic properties of oxolinic acid (OA) were studied after oral administration, intraperitoneal injection and dipping to cultured olive flounder, Paralichthys olivaceus (average 90 g, $23{\pm}1{^{\circ}C}$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. In oral dosage at 15, 30 and 60 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10~15 h post-dose, were 1.92, 2.45 and 3.72 $\mu{g}/m\ell$, respectively. In intraperitoneal injection with 10 and 20 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10 h post-dose, were 4.1 and 4.8 $\mu{g}/m\ell$, respectively. In dipping in 30 and 50 ppm for 1 h, peak concentrations were observed at 5 h and 30 h post-dose, were 0.22 and 0.38 $\mu{g}/m\ell$, respectively. The kinetic profile of absorption, distribution and elimination of OA in plasma were analyzed fitting to a one-compartment model by WinNonlin program. Calculated parameters for a single oral dosage of 15, 30 and 60 ㎎/㎏, respectively, were: AUC (the area under the concentration-time curve)=70.93, 120.0 and 141.86 $\mu{g}$ $h/m\ell$ $T_{max}$ (time for maximum concentration)=16.22, 20.39 and 17.33 h; $C_{max}$ (maximum concentration)=���D1.61, 2.40 and 3.01 $\mu{g}/m\ell$. Following intraperitoneal injection of 10 and 20 ㎎/㎏, these parameters were AUC=184.7 and 315.92 $\mu{g}$ $h/m\ell$ $T_{max}$=5.91 and 6.26 h; $C_{max}$=4.19 and 4.45 $\mu{g}/m\ell$. Following dipping at 30 and 50 ppm, these parameters were AUC=17.58 and 21.69 $\mu{g}$ $h/m\ell$ $T_{max}$=19.08 and 31.43 h; $C_{max}$x=0.22 and 0.25 $\mu{g}/m\ell$.

Pharmacokinetics of amoxicillin trihydrate in cultured eel Anguilla japonica by single oral and intravenous administrations (Amoxicillin trihydrate의 단독 경구투여 및 정맥투여에 따른 뱀장어, Anguilla japonica 체내 약물동태학적 특성)

  • Jeon, Eun-Ji;Seo, Jeong-Soo;Kim, Jin-Do;Jung, Sung-Hee;Kim, Myoung-Sug;Hwang, Jee-Youn;Park, Myoung-Ae;Jee, Bo-Young;Kim, Jin-Woo;Kim, Yi-Cheong
    • Journal of fish pathology
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    • v.23 no.3
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    • pp.357-367
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    • 2010
  • The pharmacokinetic properties of amoxicillin trihydrate (Amox) were studied after single oral administration and single intravenous injection to cultured eel, Anguilla japonica, respectively (average $220{\pm}10\;g$, $28{\pm}1^{\circ}C$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. The kinetic profile of absorption, distribution and elimination of Amox in plasma were analyzed fitting to a two-compartment model by WinNonlin program. In oral dosage of 40 and 80 mg/kg body weight, the peak plasma concentrations of Amox, which attained at 3~12 h post-dose, were 3.4 and $3.3\;{\mu}g/ml$, respectively. In intravenous injection with 1 mg/kg, the peak plasma concentrations of Amox, which attained at 9 h post-dose, was $7.2\;{\mu}g/ml$. The following parmeters were calculated for a single oral dosage of 40 and 80 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)= 464 and $667\;{\mu}g{\cdot}h/ml$; $T_{max}$ (time for maximum concentration)= 2.1 and 3.6 h; $C_{max}$ (maximum concentration)= 3.04 and $3.4\;{\mu}g/ml$. Following intravenous injection at 1 mg/kg, this parameters were AUC= $748\;{\mu}g{\cdot}h/ml$; $C_{max}=4.2\;{\mu}g/ml$. The apparent oral bioavailability at 40 and 80 mg/kg were 1.6 and 1.1%, respectively. Despite using the trihydrate form of amoxicillin, the oral bioavailability was low in eel.