• Title/Summary/Keyword: 가소성

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Physical Properties of Locust Bean Gum-Based Edible Film (Locust Bean Gum으로 제조한 가식성 필름의 물리적 특성)

  • Choi, Soo-Jin;Kim, Sang-Yong;Oh, Deok-Kun;Noh, Bong-Soo
    • Korean Journal of Food Science and Technology
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    • v.30 no.2
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    • pp.363-371
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    • 1998
  • Locust bean gum (LBG)-based edible film was prepared, and opacity, water vapor permeability (WVP), tensile strength (TS) and elongation (E) of the film were measured. Opacity values of the film was a little higher than that of other transparent films. WVP decreased as LBG concentration decreased. Plasticizers and drying temperature didn't seem to influence WVP. WVP of the film increased greatly at 85% RH as compared to that of 0% RH. WVP of the film seemed to increase linearly with thickness of the film. But WVP of the film was lower those of other edible films. TS increased with increase of LBG concentration, and decreased with increase of glycerol concentration. E decreased with increase of LBG concentration, and increased with increase of sorbitol concentratin. LBG-based composite films were prepared by adding agarose, k-carrageenan or xanthan gum. TS and E of the composite film with addition of k-carrageenan increased.

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A study on the development of phthalate plasticizers CRM in ABS resin (ABS 중 phthalates 가소제 CRM 개발에 대한 연구)

  • Jung, Jung-Sul;Park, Jung-Woo;Yoo, Seok;Kweon, Seong-Il;Hong, Sung-Taeg;Sun, Yle-Shik;Park, Cheon-Min;Choi, Chang-Hyoo
    • Analytical Science and Technology
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    • v.25 no.5
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    • pp.273-283
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    • 2012
  • Phthalate plasticizers are regulated by RoHS, REACH and CPSC as hazardous substances. Responding to these international environmental restrictions, we developed ABS certified reference material (CRM) for determination of phthalate plasticizers such as DMP, DEP, DBP, BBP, DEHP and DnOP. The candidate material has been made with ABS resin widely used in electric and electronic products and 6 kinds of phthalate plasticizers. The making of the material involved a series of processes like extruding, cooling, pelletizing, and drying using twin screw extruder. Then it has been certified according to ISO Guide 35. Using isotope dilution-gas chromatography/mass spectrometry (ID-GC/MS), homogeneity, short-term stability, and long-term stability were evaluated. The certified values were determined by using primary reference material (PRM) of KRISS for traceability. From now on, we will provide ABS CRM to national and international companies and research institutes after certification as certified reference material and registering on COMAR (code of reference material).

Structure Development of Solvent Casting Triacetyl Cellulose Film (트리아세틸 셀룰로오스 필름의 용액가공에 의한 구조변화)

  • Kim, Hyo-Gap;Kim, Hong-Suk;Kim, Han-Sung;Cho, Jin-Sik;Kim, Yong-Won;Kang, Ho-Jong
    • Polymer(Korea)
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    • v.34 no.3
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    • pp.210-214
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    • 2010
  • The structural development of triacetyl cellulose (TAC) was studied as a function of solution casting processing parameters such as dope concentration, evaporation temperature, annealing temperature and the addition of plasticizer. The crystalline structure was developed by the solution casting and the level of crystallinity was increased with increasing dope concentration and evaporation temperature. The crystalline structure could be enhanced by the annealing process after formation of TAC film. Introducing plasticizer resulted in decreasing melting temperature and crytallinity of TAC film due to the increase of chain mobility. It was also found that thermal stability of TAC was improved due to the rigid structure of applied plasticizer.

Relationship between RVA Properties and Film Physical Properties of Native Corn Starch and Hydroxypropylated Corn Starch (천연옥수수전분과 hydroxypropyl화 옥수수전분의 RVA특성과 필름 물성의 관계)

  • Han, Youn-Jeong;Kim, Suk-Shin
    • Korean Journal of Food Science and Technology
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    • v.34 no.6
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    • pp.1023-1029
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    • 2002
  • Relationship between RVA properties and physical properties of film made from native corn starch and hydroxypropylated corn starch at various levels of plasticizers was examinel. Tensile strength of the film decreased, but its elongation and water vapor permeability increased with increasing plasticizer concentration. The film with glycerol showed greater changes in physical properties than that with sorbitol. Hydroxypropylated starch film showed lower tensile strength, higher elongation, and higher water vapor permeability than the native starch film. Sorbitol resulted in films with relatively high tensile strength, whereas glycerol produced films with increased elongation. The most reliable parameters for the relationship between RVA properties and film properties were RVA peak viscosity, tensile strength, and water vapor permeability. Water vapor permeability and tensile strength had linear relationship with RVA properties. The tensile strength and water vapor permeability of film could be predicted using the RVA peak viscosity.

Review of the muscle plasticity (근육의 가소성에 대한 고찰)

  • Baek Su-Jeong;Kim Dong-Hyun;Kim Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.15 no.2
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    • pp.100-110
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    • 2003
  • The purpose of this article is to understand of the muscle adaptation based on myosin heavy chain. Especially, skeletal muscle dadptation in related to aging, unloading, training will discussed. MHC expression is highly plastic in muscles of adult mammals in accordance with the environmental conditions. These changes is called muscle plasticity. The plasticity is the atility of muscle cell to alter either the quantity of protein or the type of protein. MHC is both an important structural and regulatory protein comprising the contractile apparatus.

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Effects of Processing Modifiers on Dispersion and Rheology of Nonaqueous Mullite/Zirconia System Suspensions (뮬라이트/지르코니아계 비수성 현탁액의 분산 및 레올로지에 미치는 공정보조제의 영향)

  • Kim, Ji-Hyun;Yang, Tae-Young;Lee, Yoon-Bok;Park, Chan;Park, Hong-Chae
    • Journal of the Korean Ceramic Society
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    • v.38 no.6
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    • pp.537-544
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    • 2001
  • 뮬라이트, 지르코니아, 뮬라이트/지르코니아 비수성 현탁액의 분산 및 레올로지에 미치는 공정보조제의 영향이 침전밀도, 점도, 입자크기를 측정함으로써 검토되었다. 현탁액의 분산안정성 (높은 침전밀도와 낮은 점도로 특징 된)은 분산제+가소제+결합제를 함유하는 경우에 비하여 분산제 또는 분산제+가소제를 함유하는 경우가 우수하였다. Ball mulling 후의 입자크기분포는 공정보조제의 종류에 거의 영향을 받지 않았다. 결합제를 부가적으로 함유하는 현탁액은 상대적으로 강한 shear thinning 거동을 나타내었다.

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Neural Plasticity after Brain Injury (뇌 손상 후 신경 가소성)

  • Kwon, Young-Shil;Kim, Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.13 no.3
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    • pp.791-797
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    • 2001
  • After brain injury, patients show a wide range in the degree of recovery. By a variety of mechanisms, the human brain is constantly undergoing plastic changes. Spontaneous recovery from brain injury in the chronic stage omes about because of plasticity. The brain regions are altered. resulting in functionally modified cortical network. This review cnsidered the neural plasticity from cellular and molecular mechanisms of synapse formation to behavioural recovery from brain injury in elderly humans. The stimuli required to elicit plasticity are thought to be activity-dependent elements. especially exercise and learning. Knowledge about the physiology of brain plasticity has led to the development of methods for rehabilitation.

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A Study on the Plasticity Enhancement of Coal Fry Ash-Clay Bodies (석탄회-점토계 소지의 가소성 증진에 관한 연구)

  • 이기강;이효진;박천주;김동원;김유택;김석범
    • Journal of the Korean Ceramic Society
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    • v.33 no.2
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    • pp.135-142
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    • 1996
  • Fly Ashes which are produced from coal-fired powder plants and classified as general waste can be used as raw materials for bricks and tiles because of their compositional similarity with clays. There was a limit of substituting fly ash for clay because plasticity decreased with increasing fly ash additions. Accordingly this study tried to suggest a feastibility of enhancing the substitution ratio by controlling the interfacial properties of fly ash. The slip with 1:1 volume ratio showed that best dispersive characteristics under the condition of pH 2 Filter pressed cakes made of pH 2 slips also showed better plastickity than those of untreated ones. of pH 2 Filter pressed cakes made of pH 2 also shwoed better plasticity than those of untreated ones.

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Review : Continuous Fiber Tow Spreading Technologies and Its Applications (연속 섬유의 펼침에 대한 기술 현황 및 적용)

  • Roh, Jeong U;Lee, Woo Il
    • Composites Research
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    • v.26 no.3
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    • pp.155-159
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    • 2013
  • This paper reviewed the continuous fiber tow spreading technologies and its applications. The effect of the continuous fiber tow spreading in manufacturing process of continuous fiber reinforced thermoplastic composite was introduced theoretically. The fiber tow spreading technologies were categorized according to the spreading medium and its order during manufacturing process. The general principles, the applications, and the merits and demerits of fiber tow spreading technologies were introduced. Furthermore, the proposal for future direction of research on this issue was considered in this study.

Activity-dependent plasticity in skeletal muscle (골격근의 활동 의존적 가소성)

  • Kim, Sik-Hyun
    • PNF and Movement
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    • v.6 no.1
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    • pp.41-51
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    • 2008
  • Purpose : This paper reviews evidence supporting adaptive plasticity in skeletal muscle fibers induced by various exercise training and neuromuscular activity. Result : Skeletal muscle fiber demonstrates a remarkable adaptability and can adjust its physiologic and contractile makeup in response to alterations in functional demands. This adaptive plasticity results from the ability of muscle fibers to adjust their molecular, functional, and contractile properties in response to altered physiological demands, such as changes in exercise patterns and mechanical loading. The process of activity-dependent plasticity in skeletal muscle involves a multitude of signalling mechanisms initiating replication of specific genetic sequences, enabling subsequent translation of the genetic message and ultimately generating a series of myosin heavy chain isoform. Conclusions : Knowledge of the mechanisms and interaction of activity-dependent adaptive pathways in skeletal muscle is important for our understanding of the synthesis of muscle myosin protein, maintenance of metabolic and functional capacity with physical activity, and therapeutic intervention for functional improvement.

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