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Copper and Zinc Uptake Capacity of a Sorghum-Sudangrass Hybrid Selected for in situ Phytoremediation of Soils Polluted by Heavy Metals (식물정화를 위한 중금속 내성 작물의 선발과 수수-수단그라스 교잡종의 구리와 아연 흡수능력)

  • Oh, Soon-Ja;Koh, Seok-Chan
    • Journal of Environmental Science International
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    • v.24 no.11
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    • pp.1501-1511
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    • 2015
  • As essential trace elements, copper and zinc play important roles in many physiological events in plants. In excess, however, these elements can limit plant growth. This study selected a heavy metal-tolerant plant by analyzing seed germination and biomass of alfalfa (Medicago sativa), canola (Brassica campestris subsp. napus var. nippo-oleifera), Chinese corn (Setaria italica), and a sorghum-sudangrass hybrid (Sorghum bicolor ${\times}$ S. sudanense), and determined heavy metal uptake capacity by analyzing biomass, chlorophyll a fluorescence, and heavy metal contents under high external copper or zinc levels. The seed germination rate and biomass of the sorghum-sudangrass hybrid were higher under copper or zinc stress compared to the other three plants. The plant biomass and photosynthetic pigment contents of the sorghum-sudangrass hybrid seedlings were less vulnerable under low levels of heavy metals (${\leq}50ppm$ copper or ${\leq}400ppm$ zinc). The maximum quantum yield of PSII ($F_v/F_m$) and the maximum primary yield of PSII ($F_v/F_o$) decreased with increasing copper or zinc levels. Under high copper levels, the decline in $F_v/F_m$ was caused only by the decline in $F_m$, and was accompanied by an increase in non-photochemical quenching (NPQ). The $F_v/F_m$ declined under high levels of zinc due to both a decrease in the maximum fluorescence ($F_m$) and an increase in the initial fluorescence ($F_o$), and this was accompanied by a marked decrease in photochemical quenching (qP), but not by an increase in NPQ. Accumulations of copper and zinc were found in both aboveand below-ground parts of plants, but were greater in the below-ground parts. The uptake capacity of the sorghum-sudangrass hybrid for copper and zinc reached 4459.1 mg/kg under 400 ppm copper and 9028.5 mg/kg under 1600 ppm zinc. Our results indicate that the sorghum-sudangrass hybrid contributes to the in situ phytoremediation of copper or zinc polluted soils due to its high biomass yield.

Proposal of A Method to Enhance Pumping Efficiency of Cementitious Materials by Injecting Activation Agent to Slip-Layer and its Lab-Scale Experimental Verification (시멘트계 재료의 펌프압송성능 향상을 위한 윤활층 활성화제 주입 방법 제안 및 소규모 실험검증)

  • Lee, Jung-Soo;Yoo, Yong-Sun;Han, Jin-Gyu;Park, Chan-Kyu;Kwon, Seung-Hee
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.4
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    • pp.442-449
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    • 2017
  • In this study, a method to inject small amount of activation agent from the outside of the pipeline to the inside wall of the pipe was newly proposed to enhance pumping efficiency of cementitious materials. The activation agent is injected into the slip-layer, which is generally formed in the vicinity of the inside wall of the pipe during pumping cementitous materials. Through the injections, it is expected to decrease viscosity of slip-layer, namely, the friction between the mateirals and the pipe. The proposed method was verified by lab-scale pumping tests with mortars having water to cement ratio of 47%. The tests were performed with two different type of activation agents(superplasticizer and anionic surfactant) and three different amount of the agents(0.14, 0.28, 0.42% of the mortar volume). The compressive strength were measured with and without injecting the activation agent, and the internal pressures of pipeline were measured. When the anionic surfactant was used, there was no change in the compressive strength. As the amount of anionic surfactant increased, the pumping pressure decreased up to 71.4% at the maximum.

IN VITRO STUDY OF TOOTH TEMPERATURE CHANGE DURING POLYMERIZATION REACT10N OF THE COLD-CURED RESINS USED IN PROVISIONAL CROWN AND FIXED PARTIAL DENTURES (자가 중합 임시수복용 레진의 경화 시 외부환경 변화에 따른 치아의 온도변화)

  • Oh, Wu-Sik;Baik, Jin;Kim, Hyung-Seob;Woo, Yi-Hyung
    • The Journal of Korean Academy of Prosthodontics
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    • v.44 no.5
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    • pp.503-513
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    • 2006
  • Statement of the problem: The cold-cured resins used in fabrication of the provisional crown and fixed partial dentures could cause pulpal damage by heat generated during exothermic polymerization reactions. Purpose: In this in vitro study investigates the how external conditions such as material of the matrix, thickness of the matrix and thickness of dentin affect the temperature of the tooth during polymerization reaction of the cold-cured resins. Material and methods : To measure the temperature of the resin, metal die was maintained to the temperature of $37^{\circ}C$ with water bath to simulate the temperature of thetooth and thermocouple was placed in the center of the metal die. Acrylic pipe was cut in height of 1, 2, 3, 6, 10 mm and placed on the metal die and mixed resin was pored in the acrylic pipe As the resin polymerized temperature was recorded with the thermometer. Temperature of the resin using matrix was recorded by using the individual tray relieved in different thickness 2, 5, 7, 10 mm. The material of the matrix was irreversible hydrocolloid impression material, vinyl polysilloxane impression material and vacuum-formed template Temperature rise of the resin using different thickness of tooth section was record ed by placing tooth section on the metal die and placing resin over the tooth section. Results : Conclusion : 1. Temperature rise increased as the thickness of the resin increased but there was no significant differences over 3 mm thickness of the resin. 2. The lowest temperature rise was showed in irreversible hydrocolloid impression material and vinyl polysilloxane impression material vacuum-formed template as in orders. 3, Temperature rise of the resin decreased regardless of the thickness of the matrix when vinyl polysilloxane impression material was used as the matrix. 4 When irreversible hydrocolloid impression material was used as matrix, the temperature rise of the resin decreased as the thickness of the matrix increased and there was no temperature rise when thickness of the matrix reached 10 mm, 5. The temperature rise of the resin did not decreased when Polypropylene vacuum-formed template was used as the matrix. 6, The temperature of the resin increased as the thickness of the dentin decreased.

Crystallographical Characteristics of Solar Salts Produced from Jeonnam Area by X-Ray Diffraction Technique (X선 회절법에 의한 전남지역 천일염의 결정학적 특성)

  • Jeong, Byung-Jo;Kim, Yong;Kim, Chang-Dae;Hyun, Seung-Cheol;Ham, Gyung-Sik
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.9
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    • pp.1284-1288
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    • 2009
  • Identification of various inorganic compound crystals contained in solar salts, which are produced from 12 areas of Jeonnam, was firstly made by the X-ray diffraction (XRD) technique. The analysis of the XRD spectra was carried out on the basis of Joint Committee on Powder Diffraction Standards (JCPDS) data and the results of Energy Dispersive X-ray Spectrometer (EDX) measurements. In particular, the analysis of the XRD spectra supported that each solar salt contains $Na_2S$ (Shinan Jeungdo and Sinui), $KMgCl_3$ (Shinan Bigeum), $Ca(ClO_3)_2$ (Shinan Docho), $CaAl_4O_7$ (Haenam Songji), $CaSiO_3$ and $CaCl_2$ (Goheung) as inorganic compound crystals, which have not been reported for the solar salts. Also, the XRD results indicated that the solar salts maintain a cubic NaCl crystal structure without any change of lattice parameters etc. However, it was shown in the Field Emission Scanning Electron Microscope (FE-SEM) images that an external form of the solar salts has a lamination layer shape of a cubic structure, which is different from a simple cubic form for the purified salts and the reagent NaCl.

A Study on Apparel Products Performance Effecting the International Marketing Strategies (국제 경쟁력과 의류산업의 대응에 관한 연구)

  • 김문숙
    • Journal of the Korean Home Economics Association
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    • v.32 no.5
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    • pp.165-182
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    • 1994
  • Korea's clothing industry which has been country's leading export industry and basic strategical industry is now faced with many difficulties both domestically and internationally. Domestically it is faced with continuing shortage of manpower in both production line and management high labour cost causing increase in price putting more weight on behavior of consumers resulting in change of industrial environment and continuing structural problems of industry itself. Internationally it is faced with strengthening of import regulations and protectionism of developed countries and rapid emergence of underdeveloped countries as leading exporting nations. In reality export plays the most essential role in our economy and is especially sensitive to the external environmental factors. Already economic bloc phonomenon can be seen everywhere and is continuing to accelerate in place such as E. U in Europ, North & South America as NAFTA, and South East Asian contries which recent tendency of economic unity effort is present. These countries of such economic blocs are imposing heavy custom duties reinforcing provision of country origin and acting out strict inspection regulations in order to protect the interest of their own industry. Therefore it is vital to manufacture excellent quality goods For these reasons study in this area has brought attention in Korea as well as worldwide in the recent years. Apparel industry which requires professional technology and ability is the most competitive international business. In order to challenge the international market the high level of intelligence is most required to produce high quality goods. The purpose of this study is to analyze the relationship between functions and roles of marketing and to approach problems in more efficient manner. Apparel industry is composed of various programs such as design pattern making merchandising and textile science. To succeed in the business is to give the highest satisfaction to the targeted market. Hence this study will example the factors that determine the Cost Quality and Performance of apparel products. The study will involve following steps; firstly establish relationship between the quality concept and productivity of apparel products Secondly inquire in to marketing strategy laying stress on apparel production related factors focusing on merchandising marketing production and operations Thirdly prospect 21st century apparel industry focusing on garment production and trade and also other countries structural improvement Fourthly establish the new dimension of competitive factors by grasping the actual circumstance of Korea's apparel industry in the international market. The research method will include; First reality approach method by analysing the present state of industry Second literal analysis such as marketing comparisons between leading apparel exporting countries.

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Ice Formation on the Outer Surface of a Vertical Tube with Inside Refrigerant Boiling (관 내부 냉매비등이 있는 수직관 외부 얼음 형성 연구)

  • Nguyen, Minh Phu;Lee, Geun-Sik
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.2
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    • pp.129-135
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    • 2011
  • An ice-making model has been developed and analyzed in this study. The effects of the following on the ice formation on the outer surface of a tube in which a refrigerant flows and boils are numerically investigated: thermal resistance of the refrigerant and thermal resistance of the ice formed on the outer surface of the tube. The ice thickness and related variables are analyzed in the case of the refrigerants R22 and R134a by using the expressions for phase-change heat transfer and boiling heat transfer coefficient. Vapor qualities of the refrigerants range from 0 to 0.8. As a result, up to the first 30 min, the internal convection resistance is higher than the thermal resistance of the ice on the external surface of the tube. However, after about 30 min, the thermal resistance of the ice increases remarkably due to the increase in the ice thickness. Thus, the heat flux to the refrigerant decreases, and further, the refrigerant quality and the boiling heat transfer coefficient also decrease. As the heat transfer coefficient of R22 is higher than that of R134a, the mass of the ice formed when R22 is used is higher than that formed when R134a is used.

Research Methods on Scalp and Hair Management through the Pass of Time (시대적 흐름에 따른 두피와 모발관리에 대한 연구방법)

  • Kim Myung-Joo;Baek Seung-Hwa
    • Journal of Society of Preventive Korean Medicine
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    • v.7 no.1
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    • pp.123-132
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    • 2003
  • It is considered to be important to create aesthetically beautiful style through the change of external shape, however for the hair stylists, whose beauty expression is through hair, the role of hair doctor is becoming even more important with focus to improve the hair healthiness. Hair clinic is management of hair and scalp. It is the management process of preventing damages, while improving and cultivating healthy and shiny hair. The current concept in hair management is moving from simple hair styling to emphasis at hair management. As far as hair management is concerned, it usually includes treatment tools such as shampoo, conditioner, hair treatment and scalp scaling system, which is used for diagnosis of hair condition in order to treat the scalp. As the interest of hair healthiness becoming more wide spread, so does the breadth of clinic menu. The wide choice is to fulfill the profound desire of people, whose demands are simply to have variety in their choice. This is resulting in faucets of new value-added and differentiated products. The values that make-up the hair styles consist of mainly design (trend, preference), function(styling, management convenience) and clinic(hair quality improvement, damage repair). Shampoo and conditioner have gone beyond their original function of cleansing to providing combinational functions of treatment, to care and remedy, and advanced massage effectiveness. These are, to name a few that seem to go beyond their original function to satisfy the mental healthiness in people, the King Kong shampoo of shampooings in forward-backward manner, 5-minute shampoo massage that applies sports and relaxation massage, scalp acupunctural message and aural(ear) massage. More and more people are complaining about the damaged hair and hair loss problems due to perms, dyeing and bleaching of hair, in addition to natural scalp and hair damaging factors. Such complaints have stimulated many beauty products and various hair treatment systems being introduced with focus to provide nutrition and prevent damages to scalp and hair. As the living standards improve and the desire of people is to pursue differentiated lives, their demand also increases in hair styling products to fulfill the needs of healthy and aesthetical aspects of their lives.

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Effect of Extracellular Potassium on Delayed Rectifier Potassium Channel Proteins of KCNQ3 and KCNQ5 in Familial Hypokalemic Periodic Paralysis (가족성 저칼륨성 주기성 마비에서 세포외 칼륨농도가 지연성 정류형 채널을 형성하는 KCNQ3와 KCNQ5 단백질에 미치는 효과)

  • Kim, Sung-Jo;Kim, Dong-Hyun;Kim, June-Bum
    • Journal of Life Science
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    • v.19 no.10
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    • pp.1484-1488
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    • 2009
  • Familial hypokalemic periodic paralysis (HOKPP) is an autosomal dominant muscle disorder characterized by episodic attacks of muscle weakness with concomitant hypokalemia. Mutations in either a calcium channel gene (CACNA1S) or a sodium channel gene (SCN4A) have been shown to be responsible for this disease. The combination of sarcolemmal depolarization and hypokalemia has been attributed to abnormalities of the potassium conductance governing the resting membrane potential. To understand the pathophysiology of this disorder, we examined both mRNA and protein levels of delayed rectifier potassium channel genes, KCNQ3 and KCNQ5, in skeletal muscle fibers biopsied from patients with HOKOur results showed an increase in the cytoplasmic level of KCNQ3 protein in patients' cells exposed to 50 mM external concentration of potassium. However, mRNA levels of both channel genes did not show significant change in the same condition. Our results suggest that long term exposure of skeletal muscle cells in HOKPP patients to high extracellular potassium alters the KCNQ3 localization, which could possibly hinder the normal function of this channel protein. These findings may provide an important clue to understanding the molecular mechanism of familial hypokalemic periodic paralysis.

Synthesis of Shape Reconfigurable Janus Particles by External pH Stimuli (산세기 조절을 통해 모양 변형이 가능한 야누스 입자의 제조)

  • Eom, Naye;Kim, Jongmin;Kang, Sung-Min;Lee, Chang-Soo
    • Clean Technology
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    • v.20 no.3
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    • pp.226-231
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    • 2014
  • This study presents a micromolding for the synthesis of Janus particles with reconfigurable shape by pH stimuli. First, we use acrylic acid (AA) as pH responsive monomer in the hydrophilic part and trimethylolpropane triacylate (TMPTA) in the hydrophobic part, respectively. The change of acidity in solvent induces the swelling of hydrophilic part in the Janus particles. The pH-responsive Janus particles show different swelling ratio of hydrophilic part in according to composition of acrylic acid in diverse range (0-70% v/v) and pH (3-11). As the concentration of acrylic acid in the hydrophilic part and environmental pH increase, the hydrophilic part in the Janus particles is proportionally swelled. Second, we fabricate novel type of Janus particles with two different hydrophilicities. As a proof of concept, we have applied acrylic acid (AA) and 2-(dimethylamino)ethyl methacrylate (DAEMA) into each part because the monomers provide reverse responsive activity. As expected, these Janus particles show different shape anisotropies with reconfigurable property in accordance with the polarity of each part at same acidity of environmental solvent. We envision that the stimuli responsive Janus particles have a wide application from fundamental science to diagnostic apparatus.

Development of Real-time Monitoring Device ($\textrm{JELLI}^{TM}$ chip) for Phase Inversion of Emulsions Under Shear Flow (전단응력 하에서 에멀젼 상 변이의 실시간 측정을 위한 전기 유변학적 연구)

  • 백승재;이영진;남윤정;김진한;김한곤;강학희
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.1
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    • pp.59-62
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    • 2004
  • To know what happens to the internal structure of emulsions under high shear flow is very important for cosmetic product development because it is highly relevant to the physical degradation of emulsions during the application upon the skin. Here, in order to investigate the response of emulsions against the external shear forces, we designed a new device, .JELLI$^{TM}$ (Joint Electro-rheometer for Liquid-Liquid Inversion) chip, for the measurement of electrical and rheological properties of emulsions under shear flow. By using this device, we examined the real-time changes in conductivities of oil-in-water (O/W) and water-in-oil (W/O) emulsions on the artificial skin during large deformation under shear flow. In this study, O/W and W/O emulsions having various volumes were prepared. After emulsions were homogeneously applied on the artificial skin, the electrical resistance and viscosity changes were monitored under steady shear flow. In case of O/W emulsions, the resistance increased as a function of time. The resistance showed more dramatic increase as the increase of the internal oil phase. It was also found that the viscosity change was proportional to the resistance variation. This phenomenon might be caused by decreased resisting forces against the shear flow because of the breakdown of the internal phase.the internal phase.