• Title/Summary/Keyword: E.A. property

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Effects of TiN and ZrN Coating on Surface Characteristics of Orthodontic Wire (교정용 와이어의 표면특성에 미치는 TiN 및 ZrN 코팅영향)

  • Kim, W.G.;Kim, D.Y.;Choe, H.C.
    • Journal of the Korean institute of surface engineering
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    • v.41 no.4
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    • pp.147-155
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    • 2008
  • The dental orthodontic wire provides a good combination of strength, corrosion resistance and moderate cost. The purpose of this study was to investigate the effects of TiN and ZrN coating on corrosion resistance and physical property of orthodontic wire using various instruments. Wires(round type and rectangular type) were used, respectively, for experiment. Ion plating was carried out for wire using Ti and Zr coating materials with nitrogen gas. Ion plated surface of each specimen was observed with field emission scanning electron microscopy(FE-SEM), energy dispersive X-ray spectroscopy(EDS), atomic force microscopy(AFM), vickers hardness tester, and electrochemical tester. The surface of TiN and ZrN coated wire was more smooth than that of other kinds of non-coated wire. TiN and ZrN coated surface showed higher hardness than that of non-coated surface. The corrosion potential of the TiN coated wire was comparatively high. The current density of TiN coated wire was smaller than that of non-coated wire in 0.9% NaCl solution. Pit nucleated at scratch of wire. The pitting corrosion resistance $|E_{pit}-E_{rep}|$ increased in the order of ZrN coated(300 mV), TiN coated(120 mV) and non-coated wire(0 mV).

Probiotic Properties of Lactobacillus salivarius CPM-7 Isolated from Chicken Feces. (계분으로부터 Lactobacillus salivarius의 분리 및 생균제적 특성)

  • Lim, Soo-Jin;Jang, Sung-Sik;Kang, Dae-Kyung
    • Microbiology and Biotechnology Letters
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    • v.35 no.2
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    • pp.98-103
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    • 2007
  • To isolate probiotic lactic acid bacteria for animal, we have screened the microorganisms from chicken feces, by random selection and agar well diffusion assay. Among them, CPM-7 strain showing superior inhibitory activity against Escherichia coli was selected. By examining carbohydrates utilization, morphologic property and 16S rRNA gene sequence, CPM-7 strain was identified as Lactobacillus salivarius, then named L. salivarius CPM-7. L. salivarius CPM-7 produced thirteen enzymes in the test using API ZYM kit, and showed resistance to low pH and bile salts. It survived at pH 2 for 30 min. and pH 3 for 6 hr. And, it was able to grow in MRS medium containing 0.2% (w/v) bile salts. L. salivarius CPM-7 adhered to the jejunal epithelium cells of pig. Both the supernatant of L. salivarius CPM-7 and the its neutralized one showed high inhibitory activity against E. coli K88.

A Study on the Dielectric Properties and Electrical Conduction of PVDF Thin Films by Physical Vapor Deposition (진공 증착법으로 제작한 PVDF 박막의 유전 특성과 전기전도도에 대한 연구)

  • Gang, Seong-Jun;Lee, Won-Jae;Jang, Dong-Hun;Yun, Yeong-Seop
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.5
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    • pp.9-15
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    • 2000
  • The 3 ${\mu}{\textrm}{m}$-thick PVDF (polyvinylidene fluoride) thin film have been prepared using physical vapor deposition with electric field, and its FT-IR spectrum, dielectric property and electric conduction phenomenon have been investigated. Since the characteristic peaks are detected at 509.45 [$cm^{-1}$ /] and 1273.6 [$cm^{-1}$ /]in the FT-IR spectrum, we are confirmed that the $\beta$ -phase is dominant in the PVDF thin film. In the results of dielectric properties, the PVDF thin film shows anomalous dispersion, i.e. gradual decrease of dielectric constant with increase of frequency, and also that the dielectric absorption point changes from 200 Hz to 7000 Hz with increasing temperature of thin film, which is consistent with the Debye's theory. The activation energy ( $\Delta$H) obtained from temperature dependence of dielectric loss is 21.64 ㎉/mole. We confirm that the electric conduction mechanism of PVDF thin film is dominated by ionic conduction by investigating the dependence of the leakage current of the thin film on the temperature and the electric field.

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Effects of Angelicae Gigantis Radix pharmacopuncture on Nitric Oxide and Prostaglandin E2 Production in Macrophage (당귀약침액이 대식세포에서 산화질소(NO) 및 프로스타글란딘 (Prostaglandin) 생성에 미치는 영향)

  • Choi, You-Jin;Roh, Jeong-Du
    • Journal of Pharmacopuncture
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    • v.14 no.3
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    • pp.81-90
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    • 2011
  • Objectives : Angelicae Gigantis Radix has been known traditional medicine with antimicrobial activities and it has been widely used for treatment of blood and inflammatory diseases. In the present study, some studies examined anti-inflammation effects of Angelicae Gigantis Radix but they usually were performed by ethanol extracted Angelicae Gigantis Radix pharmacopuncture. So We investigated the inhibitory effects of Angelicae Gigantis Radix pharmacopuncture by hot water and ethanol extract on Nitric oxide(NO) and Prostaglandin $E_2$($PGE_2$) production in lipopolysaccharide(LPS) induced macrophage cell. Methods : Angelicae Gigantis Radix was extracted by ethanol and hot water. Cell viability was determined by MTT assay. To evaluate anti-inflammation effects of Angelicae Gigantis Radix pharmacopuncture, we examined NO and $PGE_2$ production in LPS induced macrophages. The concentrations of NO and $PGE_2$ were measured by Griess assay and Enzyme Immuno-Assay. Results : 1) The MTT assay demonstrated that cytotoxic effect of Angelicae Gigantis Radix pharmacopuncture by hot water extract and ethanol extract in RAW 264.7 macrophage cells were not appeared. 2) Angelicae Gigantis Radix pharmacopuncture by ethanol extract and hot water extract inhibited NO production in LPS induced macrophages significantly. 3) Angelicae Gigantis Radix pharmacopuncture by ethanol extract tended to inhibiting $PGE_2$ production in LPS induced macrophages. And Angelicae Gigantis Radix pharmacopuncture by hot water extract inhibited LPS induced production of $PGE_2$ in RAW 264.7 macrophage cells significantly. Conclusions : This study suggests that Angelicae Gigantis Radix pharmacopuncture may have an anti-inflammatory property through the inhibition of NO and $PGE_2$ production in LPS induced macrophages. It may have a therapeutic potential for the treatment of various inflammatory diseases.

Visco-Elastic Properties of Glass Fiber Manufactured by Slag Material (슬래그 원료를 사용해서 제조된 유리섬유의 점탄성 특성)

  • Lee, Ji-Sun;Kim, Sun-Woog;Ra, Yong-Ho;Lee, Youngjin;Lim, Tae-Young;Hwang, Jonghee;Jeon, Dae-Woo;Kim, Jin-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.6
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    • pp.477-482
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    • 2019
  • This study investigated the influence of the viscoelastic property of slag when producing glass fiber, MFS631 with 60% of manganese slag, 30% of steel slag, and 10% of silica stone. To fabricate the MFS631 glass bulk, slag materials were placed in an alumina crucible, melted at $1,550^{\circ}C$ for 2 h, and then annealed at $600^{\circ}C$ for 2 h. It was found that glass is non-crystalline through X-ray diffraction analysis. MFS631 fiber was produced at speed in the range of 100~300 rpm at $1,150^{\circ}C$. The loss modulus (G") and storage modulus (G') of the produced glass fiber were evaluated at high temperatures. G' and G" of MFS631 were greater than $893^{\circ}C$, and the modulus value was 136,860 pa. This is similar to the results of a general E-glass fiber graph. Therefore, it was concluded that its spinnability is similar to that of E-glass fiber; therefore, it can be commercialized.

A Study on Legal Issues with Airline Over-booking Practice (항공권 초과예약의 법률적 문제에 관한 연구)

  • Jeong, Jun-Sik;Hwang, Ho-Won
    • The Korean Journal of Air & Space Law and Policy
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    • v.27 no.2
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    • pp.143-166
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    • 2012
  • This paper deals in depth with airline over-booking practices and legal questions therefrom in the light of public interests. Chapter I as an introduction gives clear ideas of what are the over-booking, fact-revealing current state of denied boarding and nature of the problems inherent but veiled in those practices. In Chapter II, it is reviewed whether legal instruments for DBC(Denied Boarding Compensation) are adequately equipped for airline passengers in R. O. K. Upon the results of the review that international law to which Korea is a party, domestic law and administrative preparedness for the DBC are either null or virtually ineffective, the Chapter by contrast illustrates how well the U. S. and the E. U. safeguard civil rights of their passengers from such an 'institutionalized fraud' as the over-booking. In Chapter III on which a main emphasis lies, it is examined whether the over-booking practice constitutes a criminal offense: Fraud. In section 1, the author identifies actus reus and mens rea required for fraud then compares those with every aspect of the over-booking. In conjunction with the structural element analysis, he reviews the Supreme Court's precedents that lead the section into a partial conclusion that the act of over-booking judicially constitutes a crime of fraud. Despite the fulfillment of drawing up an intended answer, the author furthers the topic in section 2 by arguing a dominant view from Korean academia taking opposite stance to the Supreme Court. The commentators assert, "To consummate a crime of fraud, there must be property damage of the victim." For this notion correlates with a debate on legally protected interest in criminalization of fraud, the section 2 shows an argument over 'Rechtgut' matters specific to fraud. The view claims that the Rechtgut comes down rather to 'right to property' than 'transactional integrity' or 'fair and equitable principles'. However, the section concludes that the later values shall be deemed as 'freedom in economic decision-making' which are the benefit and protection of the penal law about fraud. Section 3 demonstrates the self-contradiction of the view as it is proved by a conceptual analysis that the infringement on freedom in economic decision-making boils down to the 'property damage'. Such a notion is better grounded in section 4 by foreign court decisions and legislation in its favour. Therefore, this paper concludes that the airline's act of over-booking is very likely to constitute fraud in both theory and practice.

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AN EXPERIMENTAL STUDY ON THE SHEAR BOND STRENGTHS OF COMPOSITE RESIN TO AIR-ABRADED ENAMEL AND DENTIN (표면처리방법에 따른 복합레진의 결합강도에 관한 실험적 연구)

  • Shin, Jae-Ho;Jang, Ki-Taeg;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.1
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    • pp.112-124
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    • 1997
  • According to extensive use of composite resin which have superior esthetic property, every effort on improving bonding strength between a tooth and composite resin has been continued. Acid etching technique is a method that micro-etches the tooth surface which provides bonding with composite resin possible. Recently, there were several reports that mechanical treatment obtained from air-abrasion can provide similar bonding strength with acid etching technique. So, this experimental study was designed to compare the shear bonding strength between using air-abrasion technique and using acid etching technique. Initially, bovine teeth were divided into enamel and dentin experimental groups. Respectively each group was categorized into three subgroups. One subgroup was acid etched with 35% phosphoric acid, then bonded with composite resin. The other subgroup was air-abraded with $50{\mu}m$ $Al_2O_3$ particles sprayed with 160psi air pressure using air abrasion unit(KCP-1000, A.D.T., U.SA), and composite resin was bonded. In another subgroup, composite resin was bonded after acid etching following air-abrasion. So, enamel experimental groups were made of E1 (acid etched only), E2(air-abraded only), E3(acid etched following air-abraded), and dentin experimental groups were made of D1(acid etched only), D2(air-abraded only), D3(acid etched following air-abraded). Each subgroup had 10 specimens. Dentin bonding system(Scotchbond Multi-purpose, 3M Co., U.S.A.) and composite resin(Z-100, 3M Co., U.S.A.) were applied on treated surface using 5mm diameter gelatin capsule as manufacturer's direction. After 1200 times thermocycling between $5^{\circ}C$ and $55^{\circ}C$, shear bond strength was measured in 5mm/min crosshead speed with Instron(Instron Co., U.S.A.), and also treated enamel and dentin were observed with SEM(JEOL Co., Japan). The following results were obtained: 1. In the enamel experimental groups, acid etched following air-abraded group had highest shear bond strength, but there was no significant difference compared to acid etched group. Air-abraded only group had lowest shear bond strength, and there was significant difference compared to the rest of groups. 2. In the dentin experimental groups, acid etched following air-abraded group had highest shear bond strength, but there was no significant difference compared to acid etched group. Air-abraded only group had lowest shear bond strength, and there was significant difference compared to the rest of groups. 3. In the SEM study, air-abraded enamel and dentin had irregular and rough surfaces.

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Effects of Ultra-high Pressure Homogenization on the Emulsifying Properties of Whey Protein Isolates under Various pH

  • Lee, Sang-Ho;Subirade, Muriel;Paquin, Paul
    • Food Science and Biotechnology
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    • v.17 no.2
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    • pp.324-329
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    • 2008
  • The effect of ultra-high pressure homogenization on the emulsifying properties of whey protein was investigated in a model emulsion made with whey protein isolate and soya oil under various pH. The emulsifying properties, the average diameter of the oil droplets ($d_{vs}$), and the protein load, were measured for each emulsion produced at different homogenization pressures (50 to 200 MPa) and pH values (4.6 to 8.0). According to the results of variance analysis and response surface, the pH had more influence on oil droplet size and protein load than homogenization pressure. The model equations, which were obtained by response surface analysis, show that pH and homogenization pressure had the major effect on oil droplet size and protein load. Higher homogenization pressure decreased the average droplet size and the protein load. Homogenization at high pressure, as opposed to low pressure, causes no overprocessing, but the effect was pH-dependent. The average diameter of the oil droplets increased slightly by decreasing the pH from 8.0 to 6.5 and then increased dramatically toward the isoelectric point of whey protein (i.e., at pH 4.6). Moreover associated droplets were found at acidic pH and their size was increased at high temperature.

A Study on Tax Ontology Construction (조세 온톨로지 구축에 관한 연구)

  • Chang, Inho
    • Journal of Korean Library and Information Science Society
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    • v.44 no.1
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    • pp.385-408
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    • 2013
  • The purpose of this study is to build the tax ontology which can be used to manage imposables by the state or local governments. In this, the tax and related concepts were analyzed and then concept hierarchy i.e., taxonomies were formed. Especially, in the concept hierarchy, after multiple inherits were decomposed as 'primitive concepts' and then Rector's 'methodology of ontology implementation normalization', in which defined concepts were recombined, was used. The methodology employed was that the tax system, which was entangled with the direct taxes, local taxes, and property taxes that has multiple-inherits, was expressed explicitly and logically. After that, automatic classification was carried out through the inference engine, consistency was verified. Finally, some practical cases of ontology created were enumerated.

A Study on the Application of Art and Culture in Luxury Fashion Brand - Focused on PRADA's Case - (럭셔리 패션 브랜드의 문화.예술 활용에 관한 연구 - PRADA를 중심으로 -)

  • Baek, Jeonghyun;Bae, Soojeong
    • Journal of Fashion Business
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    • v.16 no.5
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    • pp.146-163
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    • 2012
  • This thesis aims to present how to make secure the identity of the brand with enhancing the esthetic expression of the brand and making the ways of emotional communication in variety, through investigating closely the case of Prada representative of the typical brands that have established the unique identity by cooperating the fashion with culture and art through their ingenious and consistent efforts. In the conclusion, the culture and art was found to be applied in two fields i.e. one of design and the other of marketing. In terms of the design, the method of inserting the image into the surface of the clothing and accessories was used. In the context, the illustration techniques, photographic patterns and applying the image of the art piece could be summarized to be used. In terms of marketing, the sponsorship of the art and exhibitions, look books, animations and fashion films, epicenter, the collaboration with the other kinds of enterprise, could be regarded as four ways of the approaches. The innovation and creativity, futuristic hybrid, nonprofit support of the art, the integration and consistency of the image of the arts could be concluded to be four major points defining the characteristics of the Prada renowned for the use of the culture and arts to its property.