• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.112.2-112.2
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• 2013

지식경제부의 청정제조기반 산업원천개발사업의 일환으로 진행 중인 "초고진공펌프 개발" 과제 중 제 3세부 과제인 "고진공펌프종합특성평가시스템 설계, 진단기술 개발" 과제에서 5년 동안 진행되고 있는 전반적인 연구수행결과 및 구축 완료된 종합특성평가시스템을 활용한 고진공펌프의 상용화를 위한 신뢰성 평가에 관하여 소개한다. 고진공펌프개발 총괄 과제의 대명제는 "국제적 신뢰성을 가지는 상용화 제품의 완성"이며, 10(3) mbar~10(-10) mbar 영역의 국내 진공펌프 개발 수준의 선진화를 위한 모든 특성평가장치의 국제적 신뢰성이 있는 완벽한 성능평가의 구현을 포함한다고 볼 수 있으며, 전체 사업 추진기간 동안 제품 개발 주체인 산업체에 상용화를 위한 신뢰성 기반기술의 완벽한 구현의 제공에 있다고 할 수 있다. 이러한 고진공펌프의 신뢰성 평가는 저진공펌프의 신뢰성 평가기술에 기반을 두고 있으며, 기 개발 완료된 특성평가뿐만 아니라 실질적으로 나노종합팹센터의 공정현장에서 판단할 수 있는 내구성진단 및 최종 제품의 기계적 신뢰성 진단기술의 복합적인 요인들의 집합적인 분석에 기인하고 있다고 판단할 수 있다. 상용화 단계의 내구성 및 신뢰성 확보를 위한 전제 조건은 대외적으로 공표할 수 있는 시험평가 데이터와 개발 주체에서 기밀 수준으로 유지해야만 하는 민감한 자료의 상시 생산 infra의 구축으로 볼 수 있다. 이러한 진공펌프개발이라는 과제의 대명제를 완성하기 위한 연구개발 등 최종 상용화에 필요한 국제 신뢰성, 공정대응성 확보 기술개발 등 핵심사업 추진내용을 소개하고자 한다.

• Journal of Korea Technology Innovation Society
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• v.12 no.4
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• pp.788-818
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• 2009

Renewable energy refers to solar energy, biomass energy, hydrogen energy, wind power, fuel cell, coal liquefaction and vaporization, marine energy, waste energy, and liquidity fuel made out of byproduct of geothermal heat, hydrogen and coal; it excludes energy based on coal, oil, nuclear energy and natural gas. Developed countries have recognized the importance of these energies and thus have set the mid to long term plans to develop and commercialize the technology and supported them with drastic political and financial measures. Considering the growing recognition to the field, it is necessary to analysis up-to-now achievement of the government's related projects, in the standards of type of renewable energy, management of sectional goals, and its commercialization. Korean government is chiefly following suit the USA and British policies of developing and distributing renewable energy. However, unlike Japan which is in the lead role in solar rays industry, it still lacks in state-directed support, participation of enterprises and social recognition. The research regarding renewable energy has mainly examinedthe state of supply of each technology and suitability of specific region for applying the technology. The evaluation shows that the research has been focused on supply and demand of renewable as well as general energy and solution for the enhancement of supply capacity in certain area. However, in-depth study for commercialization and the increase of capacity in industry followed by development of the technology is still inadequate. 'Cost-benefit model for each energy source' is used in analysis of technology development of renewable energy and quantitative and macro economical effects of its commercialization in order to foresee following expand in related industries and increase in added value. First, Investment on the renewable energy technology development is in direct proportion both to the product and growth, but product shows slightly higher index under the same amount of R&D investment than growth. It indicates that advance in technology greatly influences the final product, the energy growth. Moreover, while R&D investment on renewable energy product as well as the government funds included in the investment have proportionate influence on the renewable energy growth, private investment in the total amount invested has reciprocal influence. This statistic shows that research and development is mainly driven by government funds rather than private investment. Finally, while R&D investment on renewable energy growth affects proportionately, government funds and private investment shows no direct relations, which indicates that the effects of research and development on renewable energy do not affect government funds or private investment. All of the results signify that although it is important to have government policy in technology development and commercialization, private investment and active participation of enterprises are the key to the success in the industry.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.7-12
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• 2020

Astragalus uliginosus L.-stems as a by-product of oriental medicine are produced largely in a northern area of Chungbuk province. These by-products do not have any demand and thus usually discarded into the fields as a waste. In this work, a biochar was prepared from the Astragalus uliginosus L.-stem waste for recycling. The biochar was used to investigate the removal characteristics of cadmium and manganese ions dissolved in water. When adsorption equilibrium experiments were performed to treat 50 and 100 mg/L of cadmium ions, the removal efficiencies of cadmium were 100 and 95%, respectively. In addition, the maximum of adsorption amount for manganese ions in 5 h at an initial concentration of 50 and 100 mg/L was found to be as 36.1 and 37.9 mg/g, respectively. Based on the experimental results, it was found that the adsorption amount of Astragalus uliginosus L.-stem biochar for the removal of both cadmium and manganese ions was four times higher than that of the activated carbon. The surface analysis of both biochar and activated carbon samples using X-ray photoelectron spectroscopy (XPS) analysis showed that the oxygen content and O/C ratio of biochar was 2.1 and 2.4 times higher than that of the activated carbon, respectively. In order to enhance the removal capability of manganese, 50 and 100 mg/L of manganese ions were operated at different temperatures. It was observed that these equilibrium was attained in 4 h under 45 ℃ and removal efficiencies were 92 and 53%, respectively. Consequently, the experimental results can be utilized as a new removal technology for eco-friendly and economically treating cadmium and manganese ions dissolved in water.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.687-692
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• 2016

Biomass has been concerned as one of the alternative energy resources because it is renewable, abundant worldwide, eco-friendly, and carbon neutral. Quercus variabilis has been studied to understand pyrolysis reaction characteristics, and to evaluate the efficiency of bio-energy production from fast pyrolysis. Quercus variabilis were fast pyrolyzed in a bubbling fluidized bed reactor at various reaction conditions. The effects of pyrolysis temperature between $400^{\circ}C$ and $550^{\circ}C$ on product yields were investigated. The yield of bio-oil was changed between 36.98 wt% and 39.14 wt%, and those of gas yield was 33.40 and 36.96 wt% with increasing reaction temperature. The higher heating value (HHV) of bio-oil at $500^{\circ}C$ ($3.0{\times}U_{mf}$) was 20.18 MJ/kg. The gas compositions were similar for all reaction conditions such as CO, $CO_2$ and $CH_4$, and $CO_2$ selectivity was the highest (37.16~50.94 mol%). The bio-oil has high selectivities for furfural, phenol and their derivatives such as 1-hydroxy-2-propanone, 2-methoxy-phenol, 1,2-benzendiol, 2,6-dimethoxy-phenol.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.3
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• pp.243-249
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• 2009

This study was conducted to determine the proper inclusion levels of squid liver powder (SLP) and dehulled soybean meal (DHSM) as a fish meal (FM) replacement in the diets for olive flounders. All the experimental diets were formulated to be isonitrogenous (50% crude protein, CP) and isocaloric (17.1 kJ energy $g^{-1}$ diet). Four diet were formulation of FM with SLP (DHSM) were tested at 0, 25, 50, 75% (SLP(DHSM)$_0$, SLP(DHSM)$_{25}$, SLP(DHSM)$_{50}$ and SLP(DHSM)$_{75}$, respectively). Triplicate groups of 12 fish with an average body weight of 5.56$\pm$0.1 g (mean$\pm$S.D.) were fed one of three experimental diets for 7 weeks. Weight gain (WG) and the specific growth rate(SGR) of fish fed SLP(DHSM)$_0$ and SLP(DHSM)$_{25}$ diets were significantly higher than those of fish fed SLP(DHSM)$_{50}$ and SLP(DHSM)$_{75}$ diets (P<0.05). Also, WG and SGR of fish fed SLP(DHSM)$_{50}$ had significantly higher WG and SGR than that of fish fed SLP(DHSM)$_{75}$ (P<0.05). The feed efficiency (FE) and protein efficiency ratio (PER) of fish fed SLP(DHSM)$_0$ and SLP(DHSM)$_{25}$ were significantly higher than those fed SLP(DHSM)$_{50}$ and SLP(DHSM)$_{75}$ (P<0.05). The whole-body crude lipid content of fish SLP(DHSM)$_{75}$ was significantly higher than that of fish fed SLP(DHSM)$_{50}$ (P<0.05). However, there were no significant differences in whole-body moisture, crude protein and crude ash of fish fed all diets. Based on these growth performance results, the SLP(DHSM) combination replace up to 25% FM protein by the ANOVA test in juvenile olive flounder diets.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.4
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• pp.314-319
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• 2010

This study determined the proper inclusion levels of squid liver powder (SLP) - soy protein concentrate (SPC) premix as a fish meal (FM) substitute in the diet for juvenile olive flounder (Paralichthys olivaceus). All the experimental diets were formulated to be isonitrogenous (50% crude protein) and isocaloric (17.1 kJ energy $g^{-1}$ diet). Five diets were formulated with SLP-(SPC) replacing 0, 25, 50, 75, and 100% of the FM (SLP $(SPC)_0$, SLP $(SPC)_25$, SLP $(SPC)_50$, SLP $(SPC)_75$, and SLP $(SPC)_100$, respectively). Triplicate groups of 12 fish averaging $5.56{\pm}0.10\;g$ ($mean{\pm}SD$) were fed one of the five experimental diets for 7 weeks. The weight gain (WG), specific growth rate (SGR), feed efficiency (FE), and protein efficiency ratio (PER) of fish fed SLP $(SPC)_0$ were significantly (P<0.05) higher than those of fish fed SLP $(SPC)_50$, SLP $(SPC)_75$ and SLP $(SPC)_100$, while those of fish fed SLP $(SPC)_0$ and SLP $(SPC)_25$ were similar. The whole-body crude protein content of fish fed SLP $(SPC)_0$ was significantly (P<0.05) lower than that of fish fed SLP $(SPC)_50$, SLP $(SPC)_75$, and SLP$(SPC)_100$, while those of fish fed SLP $(SPC)_0$ and SLP $(SPC)_25$ were similar. The whole-body crude lipid of fish fed SLP $(SPC)_0$ was significantly (P<0.05) lower than that of fish fed SLP $(SPC)_50$ and SLP $(SPC)_75$, while those of fish fed SLP $(SPC)_0$, SLP $(SPC)_25$ and SLP $(SPC)_100$ were similar. Based on the fish growth performance results obtained from this study, the SLP (SPC) premix can substitute up to 25% of the FM in the diets of juvenile olive flounder.

• Clean Technology
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• v.29 no.3
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• pp.200-216
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• 2023

Ginkgo leaves are considered waste biomass and can cause problems due to the strong insecticidal actions of ginkgolide A, B, C, and J and bilobalide. However, Ginkgo leaf biomass has high organic matter content that can be converted into fuels and chemicals if suitable technologies can be developed. In this study, the effect of pyrolysis temperature, minimum fluidized velocity, and Ginkgo leaf size on product yields and product properties were systematically analyzed. Fast pyrolysis was conducted in a bubbling fluidized bed reactor at 400 to 550℃ using silica sand as a bed material. The yield of pyrolysis liquids ranged from 33.66 to 40.01 wt%. The CO₂ and CO contents were relatively high compared to light hydrocarbon gases because of decarboxylation and decarbonylation during pyrolysis. The CO content increased with the pyrolysis temperature while the CO₂ content decreased. When the experiment was conducted at 450℃ with a 3.0×U_mf fluidized velocity and a 0.43 to 0.71 mm particle size, the yield was 40.01 wt% and there was a heating value of 30.17 MJ/kg, respectively. The production of various phenol compounds and benzene derivatives in the bio-oil, which contains the high value products, was identified using GC-MS. This study demonstrated that fast pyrolysis is very robust and can be used for converting Ginkgo leaves into fuels and thus has the potential of becoming a method for waste recycling.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.31-39
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• 1987

This study has been investigated the effect of Ganordema lucidum extract on Saccharomyces cerevisiae growth and physiology. Sacch. cerevisiae was inoculated in Hayduck solution medium which were added 0, 0.1, 0.5, 1.0% extracts of G. lucidum and fermented at $30^{\circ}C$ for 5 days respectively. Some results about cell number, alcohol content and carbon dioxide products during fermentation are as follows: $CO_2$ evolution of yeasts by addition of extract of G. lucidum was more increased than control after the fermentation for 120 hours. It was the most abundant by addition of 1.0% extract of pot-culture G. lucidum. The cell number of yeasts during the fermentation w as more increased than control by addition of extract of G. lucidum. It was by addition of extract of pot-culture G. lucidum that the cell number of yeasts was more increased than by each addition of extract of wood-culture G. lucidum and G. lucidum. Dry weight of yeasts was systematically increased in addition of extract of pot 0.5%>pot 1.0%>wild 1.0%>wood 1.0%=wood 0.5%>wild 0.5%>wild 0.1%>pot 0.1%>wood 0.1%>control in order. It was by addition of extract of pot-culture G. lucidum that. the dry weight of yeasts was more increased than by addition of woodculture G. lucidum and wild G. lucidum. Alcohol quantity by addition of extract of G. lucidum was increased more than 3 times after the fermentation for 72 hours compared with control but there was no any difference among them after the fermentation for 120 hours. The rate of sugar-consumption and fermentation of yeast by addition of extract of G. lucidum was highly increased during the early fermentation. As times went, there was no difference among them during the subsequent fermentation.

• Clean Technology
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• v.25 no.2
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• pp.129-139
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• 2019

Bamboo is an evergreen perennial plant, and it is known as one of the most productive and fastest-growing plants in the world. It grows quickly in moderate climates with only moderate water and fertilizer. Traditionally in Asia, bamboo is used for building materials, as a food source, and as versatile raw materials. Bamboo as a biomass feedstock can be transformed to prepare activated carbon using the thermal treatment of pyrolysis. The effect of process variables such as carbonization temperature, activation temperature, activation time, the amount of steam, and the mixing ratio of phosphoric acid and bamboo were systematically investigated to optimize the preparation conditions. Steam activation was proceeded after carbonization with a vapor flow rate of $0.8{\sim}1.8mL-H_2O\;g-char^{-1}\;h^{-1}$ and activation time of 1 ~ 3 h at $700{\sim}900^{\circ}C$. Carbon yield and surface area reached 2.04 ~ 20.59 wt% and $499.17{\sim}1074.04m^2\;g^{-1}$, respectively, with a steam flow rate of $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$ for 2 h. Also, the carbon yield and surface area were 24.67 wt% and $1389.59m^2\;g^{-1}$, respectively, when the bamboo and phosphoric acid were mixed in a 1:1 weight ratio ($700^{\circ}C$, 2 h, $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$). The adsorption of methylene blue into the bamboo activated carbon was studied based on pseudo first order and second order kinetics models. The adsorption kinetics were found to follow the pseudo second order model, which is governed by chemisorption.