• Title/Summary/Keyword: iPP

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Effect of succinylation on functional properties of soy protein isolate and qualities of soy bean curd (Succinyl화가 대두 단백질의 기능성과 두부의 품질에 미치는 영향)

  • 김수희
    • Journal of the Korean Home Economics Association
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    • v.28 no.4
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    • pp.41-50
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    • 1990
  • Soy protein was isolated from Korean soy bean 'Chang ryub' and chemically modified with succinic anhydride. Functionality of the soy protein isolate(SPI), succinylated SPI(SPPI), and PP590(commercial) at various pH were investigated. The mechanical and sensory properties of soy bean curds made from several mixing ratio of succinylated soy bean milk were observed. The solubility of SPI significantly increased with succinylation. The solubility of PP590 was lower than that of SSPI. The solubility of SPPI increased significantly in 0.03M CaCl2 solution. The emulsifying activity of SSPI increased. On the range of pH above pI the emulsifying activity of PP590 was higher than that of SPI. There was no difference in emulsion stability among the groups. The foam expansion capacity of SPPI increased at higher pH than pI but the foam stability decreased significantly above pH 9. Mechanical texture profile analysis revealed the modified soy bean curds had the lower hardniss, chewiness and cohesiveness with increased modification. The mechanical characteristics of modified soy bean curds revealed generalized Maxwell Model of 7-elements or 5-elements. In sensory evaluation, the hardness, the springiness and acceptability of modified soy bean curds were lower significantly than those of control soy bean curd.

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A Study on Thermoplastic Elastomer Blend Using Waste Rubber Powder(I): Screw Configurations, Morphologies and Mechanical Properties (폐고무 분말을 이용한 TPE 블렌드에 관한 연구(I) : 스크류 조합, 모폴로지, 기계적 물성)

  • Lee, Sung-Hyo;Hwang, Sung-Hyuk;Kim, Jin-Kuk
    • Elastomers and Composites
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    • v.36 no.2
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    • pp.86-93
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    • 2001
  • For solving the environmental problem of the waste EPDM and for new TPE blend materials, we developed a new kind of TPE material using a co-rotating twin screw extruder. To improve the mechanical properties of TPE material such as tensile strength, elongation at break, and modulus of the blend, PP and waste EPDM powder were blended with different screw configurations. The mechanical properties of the blends and morphology of the TPE were investigated. As the number of kneading disc and left-handed screw element increased, dynamic vulcanization of the material was increased because the shear stress and residence time of blends increased.

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Mechanical Properties and Impact Resistance of Hybrid Fiber Reinforced Concrete with Type of Reinforcing Fibers for Precast Concrete (하이브리드섬유보강 프리캐스트 콘크리트의 보강섬유 종류에 따른 역학적 특성 및 충격저항성)

  • Oh, Ri-On;Park, Chan Gi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.4
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    • pp.29-35
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    • 2013
  • The objective of the current study is to evaluate the effects depending on the types of reinforcing fibers being influential in view of mechanical properties and impact resistance of hybrid fiber reinforced concrete (HFRC) for applications to precast concrete structure. Hybrid fibers applied therefor were three types such as PP/MSF (polypropylene fiber+macro synthetic fiber), PVA/MAF (polyvinyl alcohol fiber+MSF) and JUTE/MSF (natural jute fiber+MSF), where the volume fraction of PP, PVA and natural jute was applied with 0.2 %, respectively, while based on 0.05 % volume fraction of MSF. The HFRC was tested for slump, compressive strength, flexural strength and impact resistance. The test result demonstrated that mixture of such hybrid fibers improve compressive strength, flexural strength and impact resistance of concrete. Moreover, it was found that HFRCs to which hydrophilic fibers, i.e. PVA/MSF and JUTE/MSF, were mixed show more improved features that HFRC to which non-hydrophilic fiber, i.e. PP/MSF was mixed. Meanwhile, the finding that PVA/MSF HFRC exhibited better performance than JUTE/MSF HFRC was attributed from the former having higher aspect ratio than that of the latter.

Effects of Heme Oxygenase-1 on VEGF Expression in Rheumatoid Arthritis (류마티스 관절염에서 HO-1에 의한 VEGF 발현 유도에 대한 연구)

  • Lee, Seung-Hoon;Kwan, Sang-Chul;Byun, Seung-Jae;Jang, Sung-Jo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.4
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    • pp.871-877
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    • 2008
  • Heme oxygenase-1 (HO-1), an inducible heme-degrading enzyme, is expressed by macrophages and endothelial cells in response to various stresses and mediators of inflammation. HO-1 has been recently implicated in regulation of angiogenesis via expression of VEGF. The purpose of this study was to determine the effects of HO-1 modulation on the collagen-induced arthritis (CIA) model and on angiogenesis via up- regulation of VEGF expression in human synovial fibroblast. DBA/1J mice were treated with an inhibitor of HO-1, tin protoporphyrin IX (SnPP), or with an inducer of HO-1, cobalt protoporphyrin IX (CoPP), from day 1 to day 35 after CIA induction. The clinical evolution of disease was monitored visually. At the end of the experiment, histopathologic changes were examined on the joints. VEGF expression in paws were measured by immunohistochemical stain. mRNA expression of HO-1 and VEGF stimulated with various concentration of $TNF-{\alpha}$, CoPP accessed on human synovial fibroblast by RT-PCR. Effects of pretreatment with SnPP on mRNA expression of HO-1 and VEGF in the presence of CoPP and $TNF-{\alpha}$ in synovial fibroblast was accessed by Real-time RT-PCR. Administration of cobalt protoporphyrin IX significantly induced the inflammatory response, with increased arthritis index and expression of VEGF in the paws of the arthritis models. Treatment with SnPP significantly reduced the severity of CIA through inhibition of joint inflammation and cartilage destruction. The expression of VEGF were also significantly reduced by SnPP treatment in the paw. CoPPIX as inducer of HO-1, increased HO-1 and VEGF expression dose dependently in synovial fibroblast. In contrast, inhibition of HO-1 activity by SnPPIX abrogated CoPPIX-induced HO-1 and VEGF production in synovial fibroblast. Stimulation with $TNF-{\alpha}$ increased HO-1 and VEGF expression itself and showed additive effect on HO-1 and VEGF expression when it treated with CoPP. When SnPP was treated with CoPP and $TNF-{\alpha}$, it abrogated the CoPP induced HO-1 and VEGF expression and also abrogated $TNF-{\alpha}$ induced HO-1 and VEGF expression in synovial fibroblast. The effects of HO-1 induction in rheumatoid arthritis results in aggravation of arthritis via up-regulation of VEGF. I concluded that inhibition of the expression or activity of HO-1 could be a therapeutic target of rheumatoid arthritis.

Synthesis of Amino-type Anion Exchanger from Acrylic Acid Grafted Polypropylene Nonwoven Fabric and Its Ion-Exchange Property (아크릴산 그라프트 폴리프로필렌 부직포로부터 아민형 음이온 교환체의 합성 및 이온교환특성(I))

  • Park, Hyun-Ju;Na, Choon-Ki
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.5
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    • pp.527-534
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    • 2006
  • The purpose of this study is the development of more effective filter-type polymer adsorbent for removal of anionic pollutants from wastewater. In order to synthesize the polymer adsorbent that possesses anionic exchangeable function, carboxyl(-COOH) group of PP-g-AA nonwoven fabric was converted into amine($-NH_2$) group by the chemical modification using diethylene triamine(DETA). FT-IR data indicate that amine group was introduced into PP-g-AA through amidation of grafted acrylic acid by reaction with DETA. The degree of amination increased with increase in the reaction time and temperature of the chemical modification process, and was significantly improved by the pre-swelling treatment of PP-g-AA with solvent and addition of metal chlorides as a catalyst in following order as $NH_4OH>MeOH{\geq}HCl{\geq}H_2O\;and\;AlCl_3>FeCl_3{\geq}SnCl_2{\gg}ZnCl_2{\geq}FeCl_2$, respectively. However, the addition of catalyst limited the reusability of DETA, hence was less useful from the viewpoint of cost effectiveness and waste management. The anion exchange capacity of the aminated PP-g-AA(PP-g-AA-Am) increased with increase in the degree of amination, but it reached maximum value at the degree of amination as about $50{\sim}60%$. The anion exchange capacity of PP-g-AA-Am was higher than those of commercial anion resins.

Estrous Response and Fertility in Postpartum Suckled Female Yaks (Bos grunniens) Treated with an Intravaginal Device Containing Progesterone(CIDR), Pregnant Mares' Serum Gonadotrophin and Prostaglandin Analogue

  • Zi, X.D.;Chang, S.;Lu, H.;Wang, X.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.4
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    • pp.470-474
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    • 2005
  • The efficiency of a short-term treatment with an intravaginal device containing progesterone (CIDR) combined with pregnant mares' serum gonadotrophin (PMSG) and prostaglandin analogue ($PGF_{2\alpha}$) was evaluated for the induction of estrus, initiation of cyclic activity, and fertility in postpartum suckled yak cows. Seventy-five postpartum suckled yak cows were assigned to three treatments: (1) insertion of a CIDR intravaginal progesterone (1.9 g) (day 0), an administration of $PGF_{2\alpha}$ (0.2 mg i.m.) on day 6 and PMSG (1,000 IU i.m.) at the time of CIDR withdrawal on day 7 (CPP group, n=28); (2) an administration of $PGF_{2\alpha}$ (0.2 mg i.m.) on day 6 and PMSG (1,000 IU i.m.) on day 7 (PP group, n=21); (3) untreated animals served as the control (CG group, n=26). Seven yak bulls were placed in pastures with the cows for natural mating. Estrus rate in the CPP group (28/28) was higher (p<0.01) than in the PP group (6/21) and in the CG group (0/26) within 96 h after the end of treatment. The first service conception rate in the CPP group (21/28) was higher (p<0.01) compared with in the PP group (2/9) as judged by serum $P_4$ concentration $\geq$2.35 ng/ml on day 21 after breeding. It is concluded that a short-term progesterone treatment combined with PMSG and prostaglandin increased the proportion of yak cows that exhibited behavioral estrus with more synchronized estrus response and satisfactory conception rate in postpartum suckled yak cows.

Production and Purification of Human Lipocortin-I Secreted by Recombinant Saccharomyces cerevisiae (재조합 Saccharomyces cerevisiae로부터 인체 리포코틴-I의 분비 생산 및 정제)

  • 김병문;정봉현
    • KSBB Journal
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    • v.10 no.3
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    • pp.343-348
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    • 1995
  • Human lipocorin-I(LCI) is a calcium ion-dependent and phospholipid-binding protein which exhibits an anti-inflammatory activity by inhibiting phospholipase A2 activity. In this study, the LCI gene containing its own terminator region was joined to GAL10 promoter-ppL (prepro-leader sequence of mating factor a). An ATG start codon of LCI gene was placed at downstream with KR endoprotease recognition site(Lys-Arg) of ppL. Recombinant S. cerevisiae harboring the LCI expression/secretion vector, pYGLPT5, was aerobicall grown on a liquid YPDG medium al $30^{\circ}C$ for 72hys. The whole cell and culture supernatant were separated after centrifugation, and the expressed LCI was analyzed by SDS-PAGE and western blotting methods. A majority fraction of the expressed LCI was found to be accumulated in the intracellular fraction, resulting in very low secretion efficiency of about 7.4%. About $500mg/\ell$ of LCI was extracellularly produced by the fed-batch culture employing the controlledfeeding of glucose and galactose. The secreted LCI was purified by ultrafiltration and hydroxylapatite column chromatography, and a purity of more than 99% was obtained.

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Isothermal Crystallization Kinetics of Quaternary Ammonium Group Grafted Polypropylene (제4암모늄기의 곁가지를 가지는 폴리프로필렌에서 등온결정화속도)

  • Liu, Guangtian
    • Polymer(Korea)
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    • v.39 no.2
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    • pp.268-274
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    • 2015
  • In this paper, the isothermal crystallization kinetics of a functional PP (FPP) with different grafting yields (GY)-methacryloxyethyltrimethyl ammonium chloride (DMC) grafted PP were investigated by differential scanning calorimetry (DSC). The results showed that the crystallization rate of FPP (GY=4.83%) was the highest for all of the studied samples. Furthermore, for the FPP with different GY, the value of $t_{1/2}$ became longer with increasing the grafting yield (GY). The possible explanation was that the quaternary ammonium groups introduced affected the crystallization process of the FPP in two opposite directions, i.e. promoting the nucleation and hindering the transport of the chain molecules towards the growing nuclei. Polarized optical micrographs showed that the DMC chains acted as nucleating agents, which accelerated the nucleation. In addition, the results showed the FPP had lower nucleation free energy than the PP. This study would be useful for designing the processing parameters of the grafted samples.

Evaluation of the Field Application of the Ready-mixed Shotcrete using the Synthetic Fiber (합성섬유를 혼입한 레디믹스트 숏크리트의 현장적용성 평가)

  • Choi, Hee-Sup;Nam, Kwan-Woo;Nam, Gi-Mok;Seo, Sin-Seok
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.1536-1539
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    • 2009
  • In this paper, The Ready-mixed Shotcrete which Factory with automatic production system is made Materials using synthetic fiber is evaluated the field application. Result of whole test, synthetic fiber(PP, PVA) is indicated almost equal result of steel fiber by rebound rate, compressive strength and bending test. especially, PP fiber(40mm, 12kg) is showed that bending strength and toughness is better than steel fiber, also I reason in that field application of synthetic fiber(PP, PVA) is proved.

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ON INTEGRAL MEANS OF DERIVATIVES OF UNIVALENT FUNCTIONS

  • Elhosh, M.M.
    • Bulletin of the Korean Mathematical Society
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    • v.24 no.1
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    • pp.13-17
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    • 1987
  • Let S denote the class of nivalent functions normalized so that f(0)=f'(0)-1=0 in vertical bar z vertical bar <1. Let $S_{\alpha}$$^{*}$, -.pi./2<.alpha.<.pi./2, denote the subclass of S that satisfies Re $e^{i{\alpha}}$zf'(z)/f(z).geq.0 in vertical bar z vertical bar <1; then f is called .alpha.-spiral-like and the case .alpha.=0 is the class of normalized starlike functions [6, pp.52]. Let T denote the class of functions f normalized as above and satisfying Im z[Im f(z)]..geq.0 in vertical bar z vertical bar <1; then f is called typically real and T contains those functions of S whose coefficients are real [6, pp.55]. Also, in view of [6, pp.231], let B(.lambda.) be the class of function normalized as above and map vertical bar z vertical bar <1 onto the complement of an arc with radial angle .lambda.(0<.lambda.<.pi./2). The radial angle is meant to be the angle between the tangent and radial vectors to the arc. This note includes a sharp version for Corollary 1 of [2] when f.mem. $S_{\alpha}$$^{*}$ as well as a logarithmic coefficient estimate.nt estimate.

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