• 제목/요약/키워드: additive effects

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고순도 수소 생성을 위한 SIP법에서 첨가제에 따른 환원 특성 (Characteristics of Redox Agent with Additive in Steam-Iron Process for the High Purity Hydrogen Production)

  • 전법주;김선명;박지훈
    • 한국수소및신에너지학회논문집
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    • 제22권3호
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    • pp.340-348
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    • 2011
  • Effects of various inorganic-metal oxide (Zr, Zn, Si, Al and Ca as promoters and stabilizers) additive on the reduction rate of iron oxide and the composition of forming hydrogen using the steam-iron cycle operation was investigated. The reduction rate of redox agent with additive was determined from weight change by TGA. The changes of weight loss and reduction rate according to redox agent with various additive affected the hydrogen purity and cycle stability of the process. The cyclic micro reactor showed that hydrogen purity exceeding 95% could be obtained by the water splitting with Si/Fe, Zn/Fe, Zr/Fe redox agents. The redox agents with these elements had an affect on redox cycle stability as a good stabilizer for forming hydrogen by the steam-iron process.

반도성 PTC 서미스터의 원적외선 방사특성에 미치는 $Sb_2O_3$의 영향 (The Effects of $Sb_2O_3$ on the Radiation Properties of a Far-Infrared in Semiconducting PTC Thermistor)

  • 조현섭;송민종;신용덕;장성환;박춘배
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 추계학술대회 논문집 학회본부
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    • pp.278-281
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    • 1991
  • 1) The specimen with 0.175[mol%] of additive $Sb_2O_3$ was minute and didn't appear porosity. The relation between the ratio of resistivity at $160^{\circ}C$ to that at $121^{\circ}C$ of the specimen with 0.175[mol%] of additive $Sb_2O_3$ was $3{\times}10^4$ and it's great value from among specimens. 2) The curie temperature of the specimen with 0.2 [mol%] of additive $Sb_2O_3$ was $140^{\circ}C$ AND it's great value from among specimens and those of other were $121^{\circ}C$ in all therefore, the specimen with above 0.2[mol%] of additive $Sb_2O_3$ is not match for PTCR 3) The variation of radiation properties of the specimen with 0.2[mol%] of additive $Sb_2O_3$ was very steep in the range of far-infrared $5{\sim}10[{\mu}m]$ but radiation percentage was very high of 0.92 in the range of $10[{\mu}m]$.

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Estimation of Additive and Dominance Genetic Variances in Line Breeding Swine

  • Ishida, T.;Kuroki, T.;Harada, H.;Fukuhara, R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권1호
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    • pp.1-6
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    • 2001
  • Additive and dominance genetic variances were estimated for purebred Landrace selected with line breeding from 1989 to 1995 at Miyazaki Livestock Experiment Station, Kawaminami Branch. Ten body measurements, two reproductive traits and fifteen carcass traits were analyzed with single-trait mixed model analysis. The estimates of narrow-sense heritabilities by additive model were in the range of 0.07 to 0.46 for body measurements, 0.05 to 0.14 for reproductive traits, and 0.05 to 0.68 for carcass traits. The additive model tended to slightly overestimate the narrow-sense heritabilities as compared to the additive and dominance model. The proportion of the dominance variance to total genetic variance ranged from 0.11 to 0.91 for body measurements, 0.00 to 0.65 for reproductive traits, and 0.00 to 0.86 for carcass traits. Large differences among traits were found in the ratio of dominance to total genetic variance. These results suggested that dominance effect would affect the expression of all ten body measurements, one reproductive trait, and nine carcass traits. It is justified to consider the dominance effects in genetic evaluation of the selected lines for those traits.

산화아연계 MOV 소자의 미세구조 및 전기적 특성에 이산화 규소가 미치는 영향 (Effects of $SiO_2$ Additive on the Microstructure and Electrical Characteristics of Zinc Oxide-Based MOV)

  • 정순철;이외천;남춘우
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 C
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    • pp.1361-1363
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    • 1997
  • Zinc oxide-based MOV was fabricated with $SiO_2$ additive ranging from 0.5 to 4.0 mol%, and the microstructure and electrical characteristics were investigated. $Zn_2SiO_4$ phase formed by $SiO_2$ additive was distributed at ZnO grains, grain boundaries, and multiple grain junctions. As the content of $SiO_2$ additive increases, average grain size decreased from 40.6 to $26.9{\mu}m$ due to the Pinning effect by $Zn_2SiO_4$ at grain boundaries Breakdown voltage and nonlinear exponent increased, and leakage current decreased in the range of $11.2{\sim}6.14{\mu}A$ with an increasing $SiO_2$. Donor concentration and interface state density decreased, and barrier height increased in the range of $0.71{\sim}1.04eV$ with an increasing $SiO_2$. While, as the content of $SiO_2$ additive, apparent dielectric constant decreased, peak frequency of dissipation factor decreased in the range of $6.45{\times}10^5{\sim}3.00{\times}10^5Hz$, and dissipation peak was $0.31{\sim}0.22$ at Peak frequency.

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Additive 공정을 이용한 미세 피치용 니켈 메탈마스크의 제조 및 특성평가 (Fabrication and Characterizations of Nickel Metal Mask with fine Pitch by Additive Process)

  • 박의철;임준형;김규태;박시홍;황수민;심종현;정승부;김봉수;주진호
    • 한국전기전자재료학회논문지
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    • 제20권11호
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    • pp.925-931
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    • 2007
  • We successively fabricated the Ni metal mask by additive method and evaluated the effects of wetting agents addition on the microstructure, hardness, and friction coefficient. In the process, the additive patterns with fine hole and pitch were made by photolithography technique and subsequently Ni plate was electroformed on the patterns. We found that the microstructure and mechanical properties were significantly varied when the different combinations of the wetting agents were used. When the wetting agents of both SF-1 and SF-2 were added, the microstructure consisted of crystal and amorphous phases, the grain size reduced to 5-40 nm, the RMS value decreased to 11.4 nm and the wear resistance improved. In addition, the hardness was as high as 638 Hv which is higher than that of commercial stainless steel mask and this improvement is probably due to the presence of amorphous Phase and fine grain size. The improvement of the wear resistance can provide a higher reliability and a longer service life.

황색종 연초(Nicotiana tabacum L.)의 엽위별 엽형질에 대한 유전자 효과분석 (Genetic Parameters for Some Leaf Characters in Flue-Cured Tobacco (Nicotiana tabacum L. ) at Two Representative Stalk Positions)

  • 조수헌
    • 한국연초학회지
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    • 제10권2호
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    • pp.117-122
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    • 1988
  • This experiment was conducted to study the nature of gene effects for the leaf characters in flue-cured tobacco. The genetic populations were derived from crosses between NC 2326 and Mc Nair 373, and NC 628 and DG-72. The generation means experiment Included the Pl, P2. Fl, F2, Bl and B2, which were frown at Taegu Experiment Station, Korea Ginseng & Tobacco Research Institute in 1984. Seedlings were transplanted to the field in a randomized block design with 3 replications. In each block, parental and Fl Plots contained 15 plants in a single row, F2, Bl and B2 plots being composed of 75 plant, in 5 rows. Leaf characters were measured of largest (middle leaf) and 5th leaf(top leaf) from the top after topping. Measurements of the length and width of leaf were obtained from the fresh the middle and top leaves, and weight of leaf, weight and width of midrib were from the satrap leaf after curing. Estimates of additive and dominance genetic variance were analyzed according to Gamble's biometrical model. The results obtained are as follows: 1. The additive gene effects were significant and larger than the dominance gene effects for all leaf and midrib characters in both stalk positions. 2. The dominance gene effects were significant for the length and width of leaf, and weight of midrib in the middle leaves. 3. The digenic epistatic effects were significant for the length and width of leaf in both stalk positions. 4. The additive gene effects were larger in the top than in the middle leaves and midrib characters.

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첨가제에 의한 구리 박막의 표면형상과 물성변화 (Effect of Additives on the Physical Properties and Surface Morphology of Copper Foil)

  • 우태규;박일송;박은광;정광희;이현우;설경원
    • 대한금속재료학회지
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    • 제47권9호
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    • pp.586-590
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    • 2009
  • The effects of additives on the surface morphology and physical properties of copper electrodeposited on polyimide(PI) film were investigated here. Two kinds of additives, an activator(additive A) and a leveler(additive B),were used in this study. Electrochemical experiments, in conjunction with scanning electron microscopy(SEM), X-ray diffraction(XRD) and a four-point probe, were performed to characterize the morphology and mechanical characteristics of copper electrodeposited in the presence of the additives. The surface roughness, crystal growth orientation and resistivity could be controlled using various quantities of additive B. High resistivity and lower peel strength were observed on the surface of the copper layer electroplated onto the electrolyte with no additive B. However, a uniform surface, lower resistivity and high flexibility were obtained with a combination of 20 ppm of additive A and 100 ppm of additive B.

DC Breakdown Strength Characteristics of Low Density Polyethylene

  • 윤재훈;정의환;임기조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 추계학술대회 논문집
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    • pp.231-231
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    • 2009
  • The main objective of the present paper is multiple effects of the incorporation of certain additives into LDPE (low density polyethylene) on some of the properties of the doped material relevant to its use as an insulating material for HVDC cables. in the present work, the effects of additive and breakdown strength, under de conditions. result of experiments are present and discussed. it is concluded that, although the incorporation of the additives may lead to certain beneficial effects such as the reduction of the dependence on temperature and breakdown strength

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RUNNING-IN OF DLC COATED STEEL IN BOUNDARY LUBRICATION

  • Stavlid, N.;Wiklund, U.
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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    • pp.137-138
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    • 2002
  • The benefits of using DLC coatings on steel in dry sliding are well known. The present study has investigated the effects of using the same materials but in a boundary lubricated environment. Tribological tests were performed using a load-scanning device and a lubricant with an extreme-pressure (EP) additive. XPS and grazing incidence XRD are used for chemical analysis. The chemical composition of the resulting tribofilm is correlated to different friction behaviors and contact loads, and indicates that high loads are beneficial for formation of low friction tribofilm.

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The Weight Function in BIRQ Estimator for the AR(1) Model with Additive Outliers

  • Jung Byoung Cheol;Han Sang Moon
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2004년도 학술발표논문집
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    • pp.129-134
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    • 2004
  • In this study, we investigate the effects of the weight function in the bounded influence regression quantile (BIRQ) estimator for the AR(1) model with additive outliers. In order to down-weight the outliers of X-axis, the Mallows' (1973) weight function has been commonly used in the BIRQ estimator. However, in our Monte Carlo study, the BIRQ estimator using the Tukey's bisquare weight function shows less MSE and bias than that of using the Mallows' weight function or Huber's weight function.

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