• Title/Summary/Keyword: GNP

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Preparation and Characterization of (La, Sr)$MnO_3$ Electrode for High Temperature Steam Electrolysis by Glycine-Nitrate Process (Glycine-Nitrate Process를 이용한 고온 수증기 전해용 (La, Sr)$MnO_3$ 전극의 합성 및 특성 연구)

  • Choi, Ho-Sang;Kim, Hyun-Jin;Ryu, Si-Ok;Hwang, Gab-Jin
    • Journal of Hydrogen and New Energy
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    • v.18 no.1
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    • pp.46-51
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    • 2007
  • LSM powder material for an oxygen-electrode(anode) of High Temperature Steam Electrolysis (RISE) was synthesized by a Modified-Glycine nitrate process(GNP). Amount of nitric acid and its concentration was varied to find out an appropriate composition for the oxygen-electrode(anode). In order to optimize the amount of Glycine used as an oxidant of self-combustion process, the ratio of Glycine to Anion was varied. $La_{0.8}Sr_{0.2}MnO_3$, $La_{0.5}Sr_{0.5}MnO_3$, and $La_{0.2}Sr_{0.8}MnO_3$ were synthesized in this study. Those LSM were dried for overnight to remove moisture from the material at $110^{\circ}C$ and were calcined 2 hours at $650^{\circ}C$ and were sintered in a furnace for 5 hours at $1400^{\circ}C$. Their structures, surface morphologies, surface areas, and weight changes were investigated with XRD, SEM, BET, and TG/DTA. The best perovskite phase for the oxygen-electrode of HTSE was obtained with $La_{0.8}Sr_{0.2}MnO_3$ formula in which 100 ml of 3M nitric acid was used in the preparation of its formula. The optimized ratio of Glycine to Anion was 2.

Korea's Stage of Technological Development and Efficiency Oriented Technology Policy (산업기술개발(産業技術開發)의 실태(實態)와 정책적(政策的) 시사점(示唆點))

  • Seong, So-mi
    • KDI Journal of Economic Policy
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    • v.14 no.2
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    • pp.77-108
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    • 1992
  • Many economists and policymakers regard the ratio of R&D investment to GNP to be a good indicator of a nation's technological capabilities. Consequently, their major policy recommendation to promote technological development is a rapid expansion in R&D investment. However, a low R&D ratio does not necessarily mean less efforts at technological advancement since the composition of technologies to be developed varies depending upon the stage of economic development. Technology policy to improve the international competitiveness of domestic industries should be based on the stage of economic development and present technological status rather than on a simple comparison with advanced countries. At Korea's stage of development, maximizing the efficiency of R&D investment is more important than enlarging the size of the investment. Strategic alliances between domestic firms and foreign enterprises should be encouraged to save time and costs involved in acquiring new technologies and learning how to use them. The government should establish institutional devices to stimulate private enterprises to internationalize their business activities such as R&D, production, and marketing. The government should also promote the development of domestic and international R&D networks, which can serve as the infrastructure for technological innovations.

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Effect of Carbon Filler and Ester Type Binder on the Reactivity and Adhesive Properties with PET Film of Conductive Paste (탄소필러와 에스테르계 바인더가 전도성 페이스트의 반응성 및 PET 필름과의 접착특성에 미치는 영향)

  • Shim, Chang Up;Ku, Hyo Sun;Kim, Youn Cheol
    • Applied Chemistry for Engineering
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    • v.33 no.4
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    • pp.381-385
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    • 2022
  • It is very important to secure the adhesion durability between the base film and the conductive paste for the development of a sensor for detecting hazardous chemicals. In this study, an ester binder was used to improve the adhesive properties which can be a problem when applying the sensor to the cross cut 0B or 1B grade. This problem was found while evaluating the adhesive properties by coating the polyaniline/graphene nano plate (GNP) paste on the polyethylene terephthalate (PET) film. When 10 wt% or more of the ester-based binder was added, the cross cut grade to which the sensor can be applied was 3B or higher. It was confirmed that the excessive addition of the binder may affect the electrical properties of the conductive paste and actually decrease the reactivity to sulfuric acid. To improve the electrical property, a carbon black (CB) content was varied resulting in the optimum electrical property observed at 2 wt% of CB.

A Study on the Economic Analysis of Chestnut Prices and Production Forecasting (밤 가격(價格)의 경제분석(經濟分析) 및 생산예측(生産豫測)에 관(關)한 연구(硏究))

  • Song, Hyung Sop;Cho, Eung Hyouk
    • Korean Journal of Agricultural Science
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    • v.14 no.2
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    • pp.263-271
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    • 1987
  • The cyclical trend and seasonal variations of chestnut prices have been analyzed to find out the chestnut price fluctuation in Korea during 1966-1985. The optimum prices, production, and plantation area for the next twenty five years (1986-2010) have been forcasted by the derived equation models. The results of study can be summarized as follows: 1. The chestnut prices were increased by 14.67 percent per annum during 1966-1972, an d decreased by 9.24 percent during 1973-1985, due to the excessive production of chestnut. 2. The chestnut prices showed the lowest price during the harvesting season, especially in October (89.1), and highest in July (109.1). Seasonal fluctuation of chestnut prices were 0.0837 (C.V value) during 1966-1975, and 0.0706 during 1976-1985. Such a seasonal fluctuation of chestnut prices tends to be even with the passage of time. 3. The equation model of predicted chestnut prices was derived as follows : PR=117788.088 - 7.60 TC/Pop + 6.585 GNP/Pop The chestnut prices will be the lowest in 1988, but increased rapidly thereafter. 4. The equation model of optimum chestnut production was derived as follows : $${\ell}n\;PD/Pop=-8.5147-0.8267{\ell}n\;PR+3.3063{\ell}n\;GNP/Pop$$ To maintain optimum chestnut prices according to this model, chestnut production should be 133,000 ton for 1988, and 1,899,000 ton for 2010. 5. Optimum chestnut plantation area will be 4,000 ha in 1988, and thereafter total plantation area will be up to 57,400 ha in 2010.

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Optical Properties of Mn-doped $ZnGa_2O_4$ for FED phosphor (Field Emission Display 응용을 위한 Mn-doped $ZnGa_2O_4$ 형광체의 광학적특성)

  • Sin, Han;Park, Sung
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1517-1519
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    • 1999
  • FED용 형광체로 사용되는 $ZnGa_2O_4$를 Glycine Nitrate Process로 합성하여 고상 반응법으로 합성한 $ZnGa_2O_4$ 분말과 비교 분석하였다. 또한 Glycine Nitrate Process로 제조시 Mn의 doping 농도를 변화시키면서 각각의 조성비에 따른 발광특성을 알아보았다. TGA 측정 결과 GNP법으로 합성된 $ZnGa_2O_4$의 경우약 $300^{\circ}C$이상에서 무게감량이 없으며, XRD 상분석 결과 연소반응 후 이미 상형성이 이루어짐을 알 수 있었다. PL측정을 결과 GP(Glycine Nitrate Process)로 제조된 $ZnGa_2O_4$ 분말의 발광효율이 고상 반응법으로 제조된 분말보다 우수하였으며, 균일하고 비표면적이 큰 단일상임이 관찰되었고, 더 작은 에너지와 시간으로 제조할 수 있는 장점이 있었다.

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Status and Perspectives of Korea Automotive Industry (한국 자동차 산업의 현황 및 전망)

  • 김주영
    • Journal of the Korean Professional Engineers Association
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    • v.37 no.5
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    • pp.42-46
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    • 2004
  • Automobile industry with history of more than 100 years is totally influencing all the economic environments and has very important wellbeing role in the World in every country of the world. Korean Automotive industry in production has only about 40 years but ranked remarkably 6th biggist in the world in the year of 2003. Nowadays The auto, industry has changed into buyer's market in competitively global battle fields and also is changing industry paradigm in product, sales, production, colarboration & emerging, etc. BRICs(Especially China)are rapidly emerging as main producers and customers in new big markets. Korea Auto. Industry faces crictical problems such as higher salary, furious labor union's striking lack of raw material, evasion of 3D works with studying engineering by students which are the key pending agenda that should be overcome for prosperous growth and development of achieving US20,000 GNP.

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Synergistic Effect of Reductase and Keratinase for Facile Synthesis of Protein-Coated Gold Nanoparticles

  • Gupta, Sonali;Singh, Surinder P.;Singh, Rajni
    • Journal of Microbiology and Biotechnology
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    • v.25 no.5
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    • pp.612-619
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    • 2015
  • We have synthesized gold nanoparticles (GNPs) using chicken feathers (poultry waste) and Bacillus subtilis RSE163. Disulfide reductase and keratinase produced by Bacillus subtilis during the degradation of chicken feather has been used to reduce Au3+ from HAuCl4 precursor to produce gold nanoparticles. The synthesized biogenic GNPs were characterized by UV-visible spectroscopy, transmission electron microscopy (TEM), and zeta potential measurements. Fourier transform infrared (FTIR) spectroscopy indicated the presence of protein capping on synthesized GNPs, imparting multifunctionality to the GNP surface. Furthermore, the nontoxic nature of biogenic GNPs was insured by interaction with Escherichia coli (ATCC11103), where TEM images and enhancement of growth rate of E. coli in log phase signified their nontoxic nature. The results indicate that the synthesis of biocompatible GNPs using poultry waste may find potential applications in drug delivery and sensing.

경제구조(經濟構造)의 변동(變動)과 경제예측(經濟豫測) - 변동계수(變動係數)벡터 자기회귀(自己回歸)모델을 이용한 분석(分析) -

  • Sim, Sang-Dal
    • KDI Journal of Economic Policy
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    • v.11 no.3
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    • pp.39-59
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    • 1989
  • 본고(本稿)는 Sims가 개발한 방법을 이용하여 우리나라와 같이 경제구조(經濟構造)가 급히 변하는 상황에서의 경제예측(經濟豫測)의 정확도(正確度)를 제고하고자 하는 시도의 일환이다. 본고(本稿)는 예측자의 사전신뢰(事前信賴)를 이용하여 계수의 값에 대하여 사전제약(事前制約)을 부과(賦課)하고 시간변동(時間變動)을 허용하는 변동계수(變動係數)벡타자귀(自歸)(TBVAR)모형(模型)의 추정방법뿐만 아니라 사전제약(事前制約)의 모수(母數)를 선택하는 방법과 오차(誤差)의 분산(分散)이 자기회귀(自己回歸)할 경우의 대처방법 등 예측(豫測)의 정확도(正確度)를 제고시키는 데 실제 사용되는 방법을 설명하고, 6변수모형(變數模型)을 이용하여 TBVAR 모델의 정확도(正確度)를 타(他) 모델과 비교한다. 정부건설(政府建設), 총통화(總通貨), 사채시장이자율(社債市場利子率), 민간건설(民間建設), 실질(實質)GNP 및 소비자(消費者) 물가지수(物價指數) 등 6변수(變數)에 대한 예측의 정확도를 "타일 U"값을 기준으로 비교할 때 TBVAR은 시간변동(時間變動)을 고려하지 않고 사전제약(事前制約)만 적용한 BVAR이나 사전제약(事前制約)도 적용하지 않은 VAR보다 대부분의 변수의 예측에 있어 더 정확하며 민간건설(民間建設)을 제외하고는 OLS보다 예측오차(豫測誤差)가 작게 나타난다.

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Impact of Clothing Tariff on Consumer Surplus in Korea after WTO Agreements(Part I) (WTO 체제가 의류산업에 미치는 영향(제1보) -관세율변화가 최종 의류소비자에게 미치는 영향-)

  • 전양진
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.1
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    • pp.108-115
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    • 1998
  • The objective of this study was to estimate the quantitative loss of the consumer surplus due to the tariffs on clothing imports during the WTO starting periods. For 1984-1996, the import price elasticity of the clothing was estimated from the regression of pet capita clothing imports on Per capita GNP, import price index and domestic producer price index. Then the quantitative losses of the consumer surplus in clothing were obtained from the simplified formula for 1990-1995. In spite of the decrease in textiles St clothing tariff rates, consumer costs were increasing, which was caused by the tremendous increase in clothing imports during the same period. The loss of the consumer surplus was 7131 billion wonts in 1995, which accounted for 6.4% of the total clothing expenditure.

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Synthesis of the $\textrm{BaTiO}_3$ Powders by the Glycine-Nitrate Process and Sintering Characteristics (Glycine-Nitrate 법에 의한 $\textrm{BaTiO}_3$ 분말합성 및 소결특성)

  • Kim, Gu-Dae;Park, Ji-Ae;Lee, Hong-Rim;Song, Hyu-Seop
    • Korean Journal of Materials Research
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    • v.9 no.1
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    • pp.51-56
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    • 1999
  • The $BaTiO_3$ powders were synthesized by GNP (Glycine-Nitrate process). The powders were prepared using carbonate and alkoxide as starting materials and nitric acid was used as a solvent for starting materials as well as an oxidant for combustion. the effects of aggregates in $BaTiO_3$ powders on green densities, sintering and dielectric characteristics were investigated. When the glycine/cation molar ratio was 1.2, reactivity of self-combustion was most intensive and the degree of aggregates after calcination was low. On sintering at $1400^{\circ}C$, maximum theoretical relative density(94.99%%0 was obtained in case of 1.2 molar ratio of glycine/cation. The dielectric constant of this sintered $BaTiO_3$ was 1919.

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