• 제목/요약/키워드: 17-KS

검색결과 169건 처리시간 0.032초

WC-Co/Cu/SM45C강접합에 미세조직 및 접합강도에 미치는 냉각속도의 영향 (Effects of cooling rate on Microstructure and Bond Strength in WC-Co/Cu/SM45C steel joint)

  • 정승부;양훈모
    • Journal of Welding and Joining
    • /
    • 제17권2호
    • /
    • pp.104-111
    • /
    • 1999
  • The interfacial microstructure and bond strength were examined for WC-Co/Cu/SM45C steel join using a nickel-plated copper in vacuum at 1323K for 0.6ks∼3.6ks. After bonding, microstructure in bonding interface was observed by OM(Optical Microscopy), SEM(Scanning Electron Microscopy) and EPMA(Eelectron Probe Micro Analyzer). The oil cooling was carried out at 353K, the cooling rate in air and furnace was 22K/s and 4.4K/s. respectively. It was found that dendritic widths increased with the content of cobalt and bonding times at 1323K. As a whole, bond strength values at the same bonding condition decreased in this order: WC-13wt.%Co/SM45Csteel. WC-8wt.%Co/SM45Csteel and WC-4wt.%Co/SM45Csteel. The bond strength of WC-13wt.%Co/S45C steel joint in oil cooling was 273MPa. This value was greatly higher than those of 125MPa in furnace cooling and 93MPa in air cooling at 1323K for 0.6ks. The bond strength values were found to be closely associated with the content of cobalt in WC-Co and cooling rate.

  • PDF

3개월생 분죽을 이용한 대나무 파티클보드의 특성 (Characteristics of Particleboards Made from Three-months-old Domestics Bamboo (Phyllostachys nigra var henonis Stapf))

  • 이화형;한기선;김관의
    • Journal of the Korean Wood Science and Technology
    • /
    • 제30권1호
    • /
    • pp.11-17
    • /
    • 2002
  • 본 연구는 요소수지(고형분함량 60%)를 사용, 분죽 3개월생 국산 대나무를 이용하여 대나무 파티클 3층 보드를 제조하고 3년생과 그 보드의 물리 기계적 성질을 비교 검토하였다. 분죽의 수령이 파티클 보드의 비중과 기건 함수율에 미치는 차이는 없었고, 제품의 두께 팽윤율은 함지율 11%부터 KS기준을 만족시켰으며 3개월생 보드가 3년생 보드보다 높은 수치를 나타냈다. 3개월생 파티클 보드의 휨강도가 함지율 3수준(9%, 11%, 13%)에서 모두 3년생보다 훨씬 높게 나타났고, 박기강도도 3개월생 보드가 3년생 보드보다 월등히 높았다. 3개월생, 3년생 보드 모두 KS기준강도보다 월등하였다. 보드의 포름알데히드 방산량값은 모두 E2 등급을 만족시켰다.

A Vinegar-processed Ginseng Radix (Ginsam) Ameliorates Hyperglycemia and Dyslipidemia in C57BL/KsJ db/db Mice

  • Han, Eun-Jung;Park, Keum-Ju;Ko, Sung-Kwon;Chung, Sung-Hyun
    • Food Science and Biotechnology
    • /
    • 제17권6호
    • /
    • pp.1228-1234
    • /
    • 2008
  • Having idea to develop more effective anti-diabetic agent from ginseng root, we comprehensively assessed the anti-diabetic activity and mechanisms of ginsam in C57BL/KsJ db/db mice. The db/db mice were divided into 4 groups; diabetic control (DC), ginsam at a dose of 300 or 500 mg/kg (GS300 or GS500) and metformin at a dose of 300 mg/kg (MT300). Ginsam was orally administered for 8 weeks. GS500 reduced the blood glucose concentration and significantly decreased an insulin resistance index. In addition, GS500 reduced the plasma non-esterified fatty acid, triglyceride, and increased high density lipoprotein-cholesterol as well as decreased the hepatic cholesterol and triglyceride. More interestingly, ginsam increased the plasma adiponectin level by 17% compared to diabetic control group. Microarray, quantitative-polymerase chain reaction and enzyme activity results showed that gene and protein expressions associated with glycolysis, gluconeogenesis, and fatty acid oxidation were changed to the way of reducing hepatic glucose production, insulin resistance and enhancing fatty acid $\beta$-oxidation. Ginsam also increased the phosphorylation of AMP-activated protein kinase and glucose transporter expressions in the liver and skeletal muscle, respectively. These changes in gene expression were considered to be the mechanism by which the ginsam exerted the anti-diabetic and anti-dyslipidemic activities in C57BL/KsJ db/db mice.

발수발유가공처리가 부직포의 차단성능에 미치는 영향 (Effect of Water-and Oil-Repellent Finish on Barrier Properties of Nonwoven Fabrics)

  • 조길수;최종명
    • 한국의류학회지
    • /
    • 제17권4호
    • /
    • pp.577-586
    • /
    • 1993
  • Pesticide protective clothing has not been frequently worn due to its lack of thermal comfort. It is important to develop fabrics which can allow the wearer to work in comfort. One of the possible way to achieve the goal is to produce fabrics with a water- and oil-repellent finish which would resist pesticide penetration but maintain some breathability. The purpose of this study were to evaluate the pesticide barrier properties of untreated and water- and oil-repellent finished nonwoven fabrics. Three types of nonwoven fabrics(Tyvek, Sontara and Kimlon) were used as test specimens. By pad-dry-cure method, each of the specimen was treated with fluorocarbon. The pesticide barrier properties (amount of pesticide penetration and residue) were measured by the gas chromatography. The performance properties of untreated and treated specimens were evaluated with respects to water pepellency(KS K 0590), oil repellency(AATCC 118), water resistance(KS K 0591, AATCC 42), water vapor transmission (KS A 1013) and air permeability(KS K 0570). The results of this study were as follows : 1) The untreated Sontara showed much more amount of pesticide penetration than untreated Tyvek and Kimlon, while the treated Sontara showed little amount of pesticide penetration. 2) After laundering, the amount of pesticide residue in the untreated and treated Sontara was less than that in Tyvek and in Kimlon. 3) Water- and oil-repellent finish improved water repellency, oil repellency, and water resistance of specimens. 4) The untreated Sontara and Kimlon showed higher water vapor transmission and air permeability than untreated Tyvek. Water vapor transmission and air permeability of treated specimen decreased compared to those of untreated.

  • PDF

DEEP INFRARED SURVEYS OF STAR FORMING REGIONS IN THE MWG AND LMC

  • NAKAJIMA YASUSHI
    • 천문학회지
    • /
    • 제38권2호
    • /
    • pp.173-174
    • /
    • 2005
  • On behalf of the IRSF/SIRIUS group, I introduce some recent results from our deep near-infrared surveys (J, Hand Ks bands, limiting magnitude of Ks=17) toward star forming regions in the Milky Way Galaxy (MWG) and Large Magellanic Cloud (LMC) with the near-infrared camera SIRIUS. We discovered a rich population of low-mass young stellar objects associated with the W3 and NGC 7538 regions in the MWG based on the near-infrared colors arid magnitudes. The high sensitivity of our survey enables us to detect intermediate-mass pre-main sequence stars, i.e. HAEBE stars, even in the LMC. We detected many HAEBE candidate stars in the N159/N160 complex star forming region in the LMC with the IRSF 1.4-m telescope. Spatial distributions of the young stellar objects indicate the sequential cluster formation in each star forming region in the complex and large scale (a few ${\times}$ 100 pc) sequential cluster formation over the entire complex.

서비스품질과 고객만족간의 인과관계 실증 분석 : Granger 검정법을 중심으로 (Investigating the Causal Relationship between Service Quality and Customer Satisfaction by Granger's Test of Casuality Method)

  • 박윤서
    • 한국경영과학회지
    • /
    • 제36권4호
    • /
    • pp.143-160
    • /
    • 2011
  • In the marketing research area, service quality and customer satisfaction have been considered as ones of the most important marketing variables. However, there has been a lot of controversy over the direction of the casual relationship between the service quality and the customer satisfaction. The purpose of this study is to investigate the casual relationship between the service quality and the customer satisfaction. Granger's test of casuality method has been used to test the casuality relationship between two variables. In this paper, we applied the Granger's test of casuality method to KS-SQI and NCSI data of 17 business area which had been gathered annually. As the research result, we found that the customer satisfaction might cause the service quality in many service area.

공구강에 형성된 복합(B+C+N) 확산층의 특성 연구 (Characterization of the complex(B+C+N) Diffusion Layers Formed on Tool Steels)

  • 이종훈;유위도;임영목;권기현
    • 연구논문집
    • /
    • 통권33호
    • /
    • pp.175-182
    • /
    • 2003
  • In this study, the wear resistance of the complex powder diffusion treated KS STD 61 has been investigatived. KS STD 61 tool steel was pretreated in quenching and tempering processes to obtain the tempered martensitic microstructure. The samples were packed with complex powder in steel pot($\Phi$90x60mm) and heated in a box furnace. the complex powder diffusion treatment are carried out at $540^{\circ}C$, $520^{\circ}C$, $500^{\circ}C$ for 40min, 1.5hr and 2.5hr. The microstructure, microhardness, wear resistance, and coating layer thickness of the complex powder diffusion treated samples were investigation. The weight loss of as heat treated sample was 0.4mg and that of the complex powder treated at $540^{\circ}C$ for 2.5hr was 0.17mg. These result means that the wear resistance of tool steels can be easily improved by the powder diffusion process at conventional tempering treatment temperature.

  • PDF

사료용 옥수수 신품종 '양안옥'의 생육특성 및 수량성 (Growth Characteristics and Productivity of Single Cross Maize New Hybrid for Silage and Grain, 'Yanganok')

  • 손범영;백성범;김정태;이진석;구자환;김선림;정건호;권영업;지희정;허창석;박종열
    • 한국초지조사료학회지
    • /
    • 제33권2호
    • /
    • pp.94-99
    • /
    • 2013
  • 양안옥은 다수성 사료용 옥수수 품종 개발을 목표로 2012년에 농촌진흥청 국립식량과학원에서 자식계통 KS164과 KS163을 교잡하여 육성한 다수성 단교잡종이다. 양안옥의 종피색은 황오렌지색이며 입질은 중간종이다. 양안옥은 2007~2008년 동안 생산력검정시험을 거쳐, 2009~2012년까지 3년간 4지역에서 지역적응시험을 실시하였다. 그 결과 우수성이 인정되어 2012 농작물 직무육성 신품종으로 결정되었고 양안옥으로 명명하였다. 양안옥의 출사일수는 대비 품종인 광평옥보다 2일 빠르다. 간장은 광평옥과 유의한 차이는 없으나 착수고율은 광평옥보다 높고 도복은 광평옥과 비슷한 정도로 강하며 후기녹체성과 이삭비율도 광평옥과 유의한 차이는 없다. 양안옥의 깨씨무늬병은 광평옥과 비슷한 중강의 저항성을 보이며, 그을음무늬병도 광평옥과 같이 강한 편이다. 검은줄오갈병, 이삭썩음병 및 조명나방도 광평옥과 같이 중 정도의 저항성을 보인다. 양안옥의 건물수량은 17.45 톤/ha이며, TDN수량은 11.96 톤/ha로 광평옥과 유의한 차이는 없었다. 양안옥의 종실수량은 8.32 톤/ha로 장다옥과 유의한 차이는 없었다. 4 : 1 (모본 : 부본) 재식비율로 동시 파종하여 채종 시험한 결과 모본의 출사기와 부본의 화분비산기간이 일치하며 채종수량은 1.79 톤/ha이었다. 양안옥은 전국적으로 재배가 가능하다.

종실용 옥수수 신품종 '신광옥'의 생육특성과 수량성 (Growth Characteristics and Productivity of New Single Cross Maize Hybrid for Grain, 'Singwangok')

  • 손범영;백성범;김정태;이진석;황종진;김선림;정건호;권영업;허창석;박종열
    • 한국초지조사료학회지
    • /
    • 제34권1호
    • /
    • pp.21-25
    • /
    • 2014
  • 신광옥은 다수성 사료용 옥수수 품종 개발을 목표로 2012년에 농촌진흥청 국립식량과학원에서 자식계통 KS172과 KS173을 교잡하여 육성한 다수성 단교잡종이다. 신광옥의 종피색은 황오렌지색이며 입질은 중간종이다. 신광옥은 2008~2009년 동안 생산력검정시험을 거쳐 2010~2012년까지 3지역에서 지역적응시험을 실시하였다. 그 결과 우수성이 인정되어 2012 농작물 직무육성 신품종으로 결정되었고 신광옥으로 명명하였다. 신광옥의 출사일수는 대비품종인 장다옥과 비슷하다. 간장은 장다옥과 비슷하나 착수고율은 장다옥보다 낮고 도복은 장다옥과 비슷한 정도로 강하다. 100주당 이삭은 장다옥보다 17개 더 많고 이삭길이는 장다옥과 비슷하며, 100립중은 장다옥과 비슷하다. 깨씨무늬병 저항성은 중강이며, 그을음무늬병에는 강한 편이다. 검은줄 오갈병, 이삭썩음병 및 조명나방 저항성은 중 정도이다. 신광옥의 종실수량은 7.8 톤/ha로 장다옥과 비슷하다. 4 : 1(모본 : 부본) 재식비율로 동시 파종하여 채종 시험한 결과 종자친(모본) 출사기와 화분친(부본) 화분비산기간이 일치하였으며 채종수량은 3.84 톤/ha이었다. 신광옥은 전국적으로 재배가 가능하다.