• 제목/요약/키워드: Green body

검색결과 683건 처리시간 0.024초

무가압 분말 충전 성형법을 이용한 알루미나 세라믹스의 제조: (I) 무가압 분말 충전 성형법 개발 및 성형체 특성 관찰 (Preparation of Alumina Ceramics by Pressureless Powder Packing Forming Method: (I) Development of Pressureless Powders Packing Forming Method and Characterization of Green Body)

  • 박정현;성재석;이상진
    • 한국세라믹학회지
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    • 제31권1호
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    • pp.31-38
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    • 1994
  • To overcome the demerit of conventional forming method, new forming method, pressureless powder packing forming method, was investigated. This technique is performed by powder packing followed by the infiltration of binder solution. Various alumina powders were used as starting materials and the powders showing good packing condition through powder packing experiment were chosen. The green densities prepared by this new forming method with these powders were lower than those of specimens by pressing method, but, nearly same density was obtained in case of green body prepared with the powders having high packing density. The distribution of binder in a green body was homogeneous and it was possible to a complex shape form by this forming method.

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초경합금 성형체 특성 변화에 미치는 유기물 결합제의 영향 (Effect of Polymeric Binders on Green body Properties of WC-Co Cemented Carbides)

  • 임영수;안선용;임재석;백용균;정태주
    • 한국분말재료학회지
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    • 제29권4호
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    • pp.291-296
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    • 2022
  • The green body of WC-Co cemented carbides containing polymeric binders such as paraffin, polyethylene glycol (PEG), and polyvinyl acetate (PVA) are prepared. The green density of the WC-Co cemented carbides increases with the addition of binders, with the exception of PVA, which is known to be a polar polymeric substance. The green strength of the WC-Co cemented carbides improves with the addition of paraffin and a mixture of PEG400 and PEG4000. In contrast, the green strength of the WC-Co does not increase when PEG400 and PEG4000 is added individually. The compressive strength of the green body increases to 14 MPa, and the machinability of the green body improves when more than 4-6 wt% paraffin and a mixture of PEG400 and PEG4000 is used. Simultaneously, the sintered density of WC-Co is as high as 99% relative density, similar to a low binder addition of 1-2 wt%.

녹차 열수 추출물이 콩단백질을 급여한 흰쥐의 칼슘대사와 골격강도에 미치는 영향 (The Effect of Hot Water Soluble Extract from Green Tea on Metabolism of Calcium and Bone Strength in rats fed Soy Protein Diet)

  • 원향례
    • 한국지역사회생활과학회지
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    • 제16권1호
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    • pp.59-64
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    • 2005
  • This study is to find out effects of hot water soluble extract from green tea, one of the Korean favorites, on the calcium metabolism and bone strength in body. To do so, calcium, phosphate, creatinine concentration and ALP activity in blood and the content of calcium and ash in the organ, the length, weight, strength in bone were measured. In addition, to find the calcium metabolism, the level of calcium intake, excretion, retention were measured. Twenty male Sprague-Dawley rats were divided into two groups and isoloated soy protein was provided as the source of protein and CaCO₃ was provided as the source of calcium. 0.5% hot water soluble extract from green tea was provided to the green tea groups and for the control group deionized water was provided. The results are as follows ; 1. There is no difference between the experimental groups in diet intake, weight gain, and the feed intake. 2. Feed efficiency ratio was low in the group which hot water soluble extract from green tea was provided. 3. There is no difference between groups the level of calcium, phosphorus, creatinine and ALP activity in serum. 4. There is no difference between groups weight, contents of ash and calcium in kidney and liver. 5. There is no difference between groups in calcium intake, absorption, excretion, and retention. 6. There is no difference between groups weight, length and strength in bone. In summary, when hot water soluble extract from green tea was provided with the amount of 150-200mg, which is taken when people generally drink as favorite tea, weight gain was reduced due to the decrease of feed efficiency ratio. However, it did not affect the availability of calcium in body at all. Thus, even if a big quantity of green tea powder or solid of hot green tea extract is not provided, the quantity obtained when people drink green tea lowers the feed efficiency ratio without reducing availability of calcium in body.

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A B-Spline Higher Order Panel Method Applied to the Radiation Wave Problem for a 2-D Body Oscillating on the Free Surface

  • Hong, D.C.;Lee, C.-S.
    • Journal of Ship and Ocean Technology
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    • 제3권4호
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    • pp.1-14
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    • 1999
  • The improved Green integral equation using the Kelvin-type Green function in known free of irregular frequencies where the integral over the inner free surface integral is removed from the integral equation, resulting in an overdetermined integral equation. The solution of the overdetermined Green integral equation is shown identical with the solution of the improved Green integral equation Using the B-spline higher order panel method, the overdetermined equation is discretized in two different ways; one of the resulting linear system is square and the other is redundant. Numerical experiments show that the solutions of both are identical. Using the present methods, the exact values and higher derivatives of the potential at any place over the wetted surface of the body can be found with much fewer panels than low order panel method.

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Closed-form Green's functions for transversely isotropic bi-solids with a slipping interface

  • Yue, Zhong Qi
    • Structural Engineering and Mechanics
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    • 제4권5호
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    • pp.469-484
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    • 1996
  • Green's functions are obtained in exact closed-forms for the elastic fields in bi-material elastic solids with slipping interface and differing transversely isotropic properties induced by concentrated point and ring force vectors. For the concentrated point force vector, the Green functions are expressed in terms of elementary harmonic functions. For the concentrated ring force vector, the Green functions are expressed in terms of the complete elliptic integral. Numerical results are presented to illustrate the effect of anisotropic bi-material properties on the transmission of normal contact stress and the discontinuity of lateral displacements at the slipping interface. The closed-form Green's functions are systematically presented in matrix forms which can be easily implemented in numerical schemes such as boundary element methods to solve elastic problems in computational mechanics.

옥상녹화가 PV모듈 발전량에 미치는 영향 고찰 (A study on the effect that the green roof has on the performance of PV module)

  • 유동철;이응직
    • 한국태양에너지학회 논문집
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    • 제32권2호
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    • pp.113-119
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    • 2012
  • This study aims to examine the effect of the combined application of green roof and PV system on the PV efficiency by measuring the temperature and performance of PV module in order to reduce the temperature on the roof using roof planting system and determine the potential of efficient increase in solar-light power generation. In the experimental methodology, either monocrystalline or polycrystalline PV module was installed in green roof or non-green roof, and then the surface temperature of PV was measured by TR-71U thermometer and again the performance, module body temperature, and conversion efficiency were measured by MP-160, TC selector MI-540, and PV selector MI-520, respectively. As a result, the average body temperature of monocrystalline module was lower by $6.5^{\circ}C$ in green roof than in non-green roof; that of polycrystalline module was lower by $8.8^{\circ}C$ in green roof than in non-green roof. In the difference of generation, the electricity generation of monocrystalline module in green roof was 46.13W, but that of polycrystalline module was 68.82 W, which indicated that the latter produced 22.69W more than the former.

Prevention of Olanzapine-induced Toxicities of Weight Gain and Inflammatory Reactions by Coadministration with Green Tea or its Major Component Phenolic Epigallocatechin 3-Gallate in Mouse

  • Kim, Chul-Eung;Mo, Ji-Won;Kim, Jin;Kang, Ju-Hee;Park, Chang-Shin
    • Molecular & Cellular Toxicology
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    • 제3권2호
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    • pp.127-131
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    • 2007
  • Chronic treatment with olanzapine (OLZ), an atypical antipsychotic drug, is associated with the adverse effects of weight gain, hyperglycemia and/or hypertriglyceridemia. Green tea or epigallocatechin gallate (EGCG), one of the most abundant green tea polyphenols, significantly reduces or prevents an increase in glucose levels, lipid markers and/or body weight. We hypothesized that combined treatment with OLZ and green tea extract (GTE) or EGCG may prevent body weight gain and increase of the lipid markers. ICR male mice weighing an average of 30.51 g (n=32) at the beginning of the experiment were used. OLZ, OLZ+GTE and OLZ+EGCG were administered for 27 d in the drinking water, and then the levels of fasting glucose, nitric oxide (NO), and a typical lipid marker triglyceride (TG) were determined in plasma. The body weight and food intake were also compared. The chronic treatment of OLZ increased the average body weight compared with that of controls. In the presence of GTE or EGCG, the OLZ-induced increase in body weight was significantly prevented. Furthermore, in the OLZ group, the plasma levels of glucose, NO and TG were significantly increased, whereas GTE or EGCG prevented these increases. These results implicate that OLZ may induce systematic inflammatory reaction, and suggest that GTE or EGCG can protect against OLZinduced weight gain, hyperglycemia and hypertriglyceridemia.

표고 톱밥배지 재배시 녹색LED 광량이 자실체 생육에 미치는 영향 (Effects of fruit body characteristics of Lentinula edodes according to irradiation intensity of the green LED with sawdust substrate cultivation)

  • 백일선;정윤경;이윤혜;김정한;지정현
    • 한국버섯학회지
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    • 제12권4호
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    • pp.270-274
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    • 2014
  • 표고 톱밥배지 재배시 녹색LED 광량에 따른 생육특성분석 결과 $5umol{\cdot}m^{-2}{\cdot}s^{-1}$에서 3주기 기준 배지당 자실체의 수량은 239 g으로 형광등 202 g 대비 18% 증수효과가 있었으며, 자실체 폴리페놀 함량은 형광등 107 ppm에 대비 78.4 ppm으로 27% 정도 낮았지만 에르고스테롤 함량은 형광등 145 ppm 대비 307 ppm으로 2.1배 높은 함량을 보였다. 전력소모량은 형광등 대비 15.9%의 에너지 절감율을 보였으며, 전등의 에너지 효율이 77.5%로 가장 컸다.

파랑중에서 전진하는 선박의 부가저항 해석 (Analysis of added resistance of a ship advancing in waves)

  • 이호영;곽영기
    • 한국해양공학회지
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    • 제11권2호
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    • pp.91-99
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    • 1997
  • This paper presents theoretical formulations and numerical computations for predicting first-and second-order hydrodynamic force on a ship advvancing in waves. The theoretical formulation leads to linearized radiation and diffration problems solving the three-dimensional Green function integral equations over the mean wetted body surface. Green function representing a translating and pulsating source potantial for infinite water depth is used. In order to solve integral equations for three dimentional flows using Green function efficiently, the Hoff's method is adopted for numerical calculation of the Green function. Based on the first-order solution, the mean seconder-order forces and moments are obtained by directly integrating second-order pressure over the mean wetted body surface. The calculated items are carried out for analyzing the seakeeping characteristics of Series 60. The calculated items are hydrodynamic coefficients, wave exciting forces, frequency response functions and addd resistance in waves.

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Fabrication of Light Aggregates Using the Fly Ash-Clay Slurry

  • Seunggu Kang;Lee, Kigang;Kim, Jungwan
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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    • pp.81-86
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    • 1998
  • The light aggregates were fabricated by sintering green bodies made form the fly ash-clay alip. The content of fly ashes in the slip could be increased up to 70wt.% due to controlled rheological behavior of the slip, and the green body of uniform microstructure could be obtained by DCC(Direct Coagulation Casting)method. The apparent density, microstructure and compressive strength for sintered bodies fired at 1100∼1200$^{\circ}C$ were evaluated. The properties of light aggregates fabricated depend on slip density, particle behavior in the slip and sintering conditions. The sintered body prepared by firing a green body made from slip of density 1.60 at 1150$^{\circ}C$/2hr satisfied conditions of a light aggregate as apparent density of 1.49${\pm}$0.02 and compressive strength of 584${\pm}$62kg/$\textrm{cm}^2$.

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