• Title/Summary/Keyword: carbon-reduction

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Electrocatalytic activity of carbon-supported near-surface alloys (NSAs) for electrode reaction of fuel cell (연료전지 전극 반응을 위한 카본 담지 표면 합금의 전기촉매 활성)

  • Park, In-Su;Sung, Yung-Eun
    • New & Renewable Energy
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    • v.2 no.4 s.8
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    • pp.64-69
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    • 2006
  • There is a worldwide interest in the development and commercialization of polymer electrolyte membrane fuel cells [PEMFCs] for vehicular and stationary applications. One of the major objectives is the reduction of loaded electrode materials, which is comprise of the Pt-based noble metals. In this paper, a novel chemical strategy is described for the preparation and characterization of carbon-supported and surface-alloys, which were prepared by using a successive reduction process. After preparing Au colloid nanoparticles, the supporting of Au colloid nanoparticles occurred spontaneously in the carbon black-dispersed aqueous solution. Then nano-scaled active materials were formed on the surface of carbon-supported Au nanoparticles. The structural and electrochemical analyses indicate that the active materials were deposited on the surface of Au nanoparticles selectively and that an alloying process occurred during the successive reducing process. The carbon-supported & surface-alloys showed the higher electrocatalytic activity than those of the particle-alloys and commercial one [Johnson-Matthey] for the reaction of methanol and formic acid oxidation. The increased electrocatalytic activity might be attributed to the effective surface structure of surface-alloys, which have a high utilization of active materials for the surface reaction of electrode.

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The Effects of Sonic Waves on the Reduction of Aromatic Nitro Groups Using Iron, Hydrazine Hydrate and Activated Carbon (유기 초음파화학. 초음파가 히드라진, 철, 활성탄을 이용한 방향족 니트로기의 환원반응에 미치는 영향)

  • Dae Hyun Shin;Byung Hee Han;Sung Yun Cho
    • Journal of the Korean Chemical Society
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    • v.30 no.1
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    • pp.105-108
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    • 1986
  • Ultrasound(50KHz) accelerated the reduction reaction of aromatic nitro group to aromatic amino group in high yield with mild condition using iron, hydrazine hydrate and activated carbon under room temperature and atmospheric pressure. The activated carbon has been used as a mixing material to highly active metals. However, aromatic nitro group does not reduce at all only with iron-hydrazine witliout adding activated carbon even under ultrasonic irradiation. We also discovered that the conversion yield from nitro group to amino group is directly proportional to the amount of activated carbon.

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Brief Review on Carbon Dioxide Capture and Utilization Technology (CCU 기술 국내외 연구동향)

  • Kim, Hak Min;Nah, In Wook
    • Korean Chemical Engineering Research
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    • v.57 no.5
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    • pp.589-595
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    • 2019
  • The policies and researches for the reduction of greenhouses gases have been performed according to"Paris Agreement". Because South Korea is the $6^{th}$ biggest greenhouses gas emitter in the world, the Korea government has prepared the strategies for the reduction of greenhouse gases. The development of CCUS (Carbon Capture Utilization and Storage) technology is necessary to reduce greenhouse gases. Therefore, the CCUS has been studied by many contries in the world. In this work, the trends of CCUS technologies R&D has been shortly investigated.

Synthesis of Sialon by Carbothermal Reduction of Porous Glass (다공질유리의 탄소 열적환원반응에 의한 Sialon의 합성에 관한 연구)

  • 김병호;이덕열;김왕섭;전형우;이근헌
    • Journal of the Korean Ceramic Society
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    • v.26 no.6
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    • pp.771-782
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    • 1989
  • Synthesis of $\beta$-Sialon powder was attempted with carbothermal reduction of porous glass. The porous glass was prepared by heat and hydrothermal treatments of 9.32 Li2O.46.5B2O3.37.2SiO2.6.98Al2O3 glass. Carbon pyrolyzed from propane gas was deposited on the porous glass, thereafter activated carbon was added as reducing agents. The synthesized $\beta$-Sialon powder was pressureless sintered at 175$0^{\circ}C$ for 1hr in N2 atmosphere. The characterization of the $\beta$-Sialon powder was performed with XRD, BET, SEM and particle size analysis. The sinterability and mechanical properties of the sintered bodies were investigated in terms of bulk density, M.O.R., fracture toughness, morphology of microstructure and etc. The reduction effect of deposited carbon was better than that of activated carbon mechanically added. The formation of SiC was precominant over that of Si2ON2 and $\beta$-Sialon owing to low partial pressure of N2 inside the pore, wehreas on the surface of porous glass the formation of Si2ON2 and $\beta$-Sialon were predominant. Thereafter, SiC reduced unreacted glass to be $\beta$-Sialon. Single phase of $\beta$-Sialon(Z=1.92) was obtained from PGA porous glass having the largest pore radius by the simultaneous reduction and nitridation method at 145$0^{\circ}C$ for 5hrs. The bulk density, M.O.R., and KIC of the sitered body are 3.17g/cc, 434.4MPa and 4.1MPa.m1/2, respectively.

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Effects of Activated Carbon on the Reduction of Benzo(a)pyrene in Artemisia argyi Extract

  • Lee, Sung-Hoon
    • Journal of People, Plants, and Environment
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    • v.23 no.5
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    • pp.537-544
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    • 2020
  • Background and objective: Artemisia argyi has a long history as an effective treatment for various diseases. The detection of environmental pollutant benzo(a)pyrene, a known human carcinogen, in the leaves of Artemisia argyi is cause for concern. For medicinal plant extracts, both a reduction of benzo(a)pyrene as well as the maintained effectiveness of the compound are important. Therefore, in this study, we propose an optimized process for the addition and filtration of activated carbon to reduce benzo(a)pyrene and change the contents of the indicating substance(jaceosidine and eupatilin). Methods: Artemisia argyi EtOH extract containing 36 ppb of benzo(a)pyrene was added to 0.1, 0.5, 1.0, and 1.5% (w/w) of activated carbon for 120 min and filtered using an activated carbon filter 1, 2, 3, and 5 times respectively. The content of benzo(a)pyrene and indicating substances in Artemisia argyi extract were then measured with high performance liquid chromatography (fluorescence and UV detectors). Results: As the amounts of activated carbon powder and filtering cycles increased, the content of benzo(a)pyrene in the Artemisia argyi extract decreased. However, when activated carbon powder 1.5% was added to the extract, and when the activated carbon filter was filtered five times, the results were reduced by 15% and 30~40% respectively. The optimal extraction condition for reducing benzo(a)pyrene was adding 1.5% of activated carbon powder. This resulted in reducing benzo(a)pyrene by 83% and indicating substances by about 4%. Conclusions: Here we present a process for reducing benzo(a)pyrene in Artemisia argyi extract using activated carbon to reduce toxicity and minimize the loss of active ingredients. This approach has potential application within a manufacturing process of various medicinal plant extracts.

The Analysis of Carbon Emission Costs under Milk Run Logistics Strategy (순회배송 물류전략에서 탄소배출 비용의 효과 분석)

  • Min, Daiki
    • Journal of the Korean Operations Research and Management Science Society
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    • v.40 no.1
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    • pp.21-33
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    • 2015
  • This paper develops an analytic model for minimizing the cost of distributing items by truck from one supplier to many customers under Milk run logistics strategy. The model derives formulas for not only inventory and transportation costs but also costs associated with carbon emission trading scheme. In addition, monetary investment for reducing carbon emissions is considered. We analyze how to determine optimal shipment size and carbon emission reduction investment. The purpose of this work is to evaluate the effects of carbon emission trading scheme on the Milk run logistics strategy in terms of how much to reduce carbon emissions and/or inventory and transportation costs. We analytically show that it is possible to reduce carbon emissions while reducing inventory and transportation costs by introducing cap-and-trade carbon emission trading scheme under certain conditions.

Study of Garlic's Carbon Footprint though LCA (전과정평가를 통한 마늘의 탄소배출량 산정연구)

  • Yoon, Sung-Yee;Kim, Young-Ran;Kim, Tae-Ho;Park, Jin-Hyun;Ahn, Sung-Woo
    • Korean Journal of Organic Agriculture
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    • v.20 no.2
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    • pp.161-172
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    • 2012
  • This study was carried out to estimate carbon footprint and to establish of LCA of garlic production system. We have case study in cultivate garlic 1 kg calculate in carbon footprint. LCA carried out to estimate carbon footprint and to establish of LCI (life cycle inventory) database of garlic production system. The data is from Research of Farmer's income in 2010 (RDA, 2011), and used Pass (5.0.0) program. The value of fertilizer, amount of pesticide input were shown the environmental effect and direct emission. Carbon footprint in agriculture guarantees the choice right the consumer to choose the lower carbon goods. Its can make to strengthen of agriculture and food industry's reduction effort of $CO_2$. Nowadays consumer requests food's safety and environment friendly process. Carbon footprint also needs consumer's relief and incentives.

Development of Carbon-Ceramic Composites using Fly Ash and Carbon Fibers as Reinforcement

  • Manocha, S.;Patel, Rakesh
    • Carbon letters
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    • v.7 no.1
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    • pp.27-33
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    • 2006
  • Carbon-ceramic composites were fabricated by using fly ash and PANOX fibers as reinforcement. Fly ash, because of its small size particles e.g. submicron to micron level can be effectively dispersed along with fibrous reinforcements. Phenolic resin was used as carbon precursor. Both dry as well as wet methods were used for forming composites. The resulting composites were characterized for their microstructure, thermal and mechanical properties. The microstructure and mechanical properties of composites are found to be dependent on type of the fly ash, fibrous reinforcements as well as processing parameters. The addition of fly ash improves hardness and the fibers, which get co-carbonized on heat treatment, increase the flexural strength of the carbon-ceramic composites. Composites with dual reinforcement exhibit about 30-40% higher strength as compared to the composites made with single reinforcement, either with fly ash as filler or with chopped fibers.

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A Study on the CO2 Balance Evaluation of Building and Civil Engineering Structures (건축 및 토목 구조물의 CO2 수지 평가에 관한 연구)

  • Cho, Hyeong-Kyu;Song, Hun;Lee, Han-Seung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2011.05a
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    • pp.121-122
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    • 2011
  • Globally about 40% of total carbon dioxide emissions occupies from the construction industry. Therefore, it is important to quantitatively calculate carbon dioxide emission of concrete prior to the reduction of carbon dioxide. ddd In addition, it is also important to quantitatively calculate carbon dioxide absorption of concrete because concrete absorbs in a measure of carbon dioxide. In this study, it carried out carbon dioxide balance evaluation of building and civil engineering structures through carbon dioxide balance evaluation method of concrete. Consequently absorption rate compared with carbon dioxide emission is about 2.5~5.18%.

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Development of Tree Carbon Calculator to Support Landscape Design for the Carbon Reduction (탄소저감설계 지원을 위한 수목 탄소계산기 개발 및 적용)

  • Ha, Jee-Ah;Park, Jae-Min
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.1
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    • pp.42-55
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    • 2023
  • A methodology to predict the carbon performance of newly created urban greening plans is required as policies based on quantifying carbon performance are rapidly being introduced in the face of the climate crisis caused by global warming. This study developed a tree carbon calculator that can be used for carbon reduction designs in landscaping and attempted to verify its effectiveness in landscape design. For practical operability, MS Excel was selected as a format, and carbon absorption and storage by tree type and size were extracted from 93 representative species to reflect plant design characteristics. The database, including tree unit prices, was established to reflect cost limitations. A plantation experimental design to verify the performance of the tree carbon calculator was conducted by simulating the design of parks in the central region for four landscape design, and the causal relationship was analyzed by conducting semi-structured interviews before and after. As a result, carbon absorption and carbon storage in the design using the tree carbon calculator were about 17-82% and about 14-85% higher, respectively, compared to not using it. It was confirmed that the reason for the increase in carbon performance efficiency was that additional planting was actively carried out within a given budget, along with the replacement of excellent carbon performance species. Pre-interviews revealed that designers distrusted data and the burdens caused by new programs before using the arboreal carbon calculator but tended to change positively because of its usefulness and ease of use. In order to implement carbon reduction design in the landscaping field, it is necessary to develop it into a carbon calculator for trees and landscaping performance. This study is expected to present a useful direction for ntroducing carbon reduction designs based on quantitative data in landscape design.