• 제목/요약/키워드: Specific Harmful Substances

검색결과 20건 처리시간 0.028초

수소 혼소 디젤 기관의 성능 및 미립자상 물질의 배출 특성에 관한 연구 (A Study on the Performance and Particulate Emission Characteristics for the Hydrogen-Premixed Diesel Engine)

  • 채재우;한동성;이상만;전영남;정영식
    • 한국자동차공학회논문집
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    • 제1권2호
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    • pp.34-41
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    • 1993
  • In order to reduce harmful substances such as particulates and nitric oxides emitted from diesel engine, man kinds of methodology like high pressure spray of diesel fuel oil, exhaust gas recirculation, emulsified fuel usage and dual fuelling have been studied. Dual fuelling of a diesel engine with hydrogen which is well-known as the clean fuel and has excellent combustibility is expected to be effective in reducing harmful substances from diesel engine. This experimental study was conducted to investigate the effect of premixed hydrogen with intake air on the performance and particulate emission characteristics using a single cylinder, prechamber type diesel engine. As a result, it was clarified that a hydrogen-premixed diesel engine can be operated in the state of lower particulate emission and slightly aggravated fuel economy, compared with the conventional diesel engine.

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Cochlodinium polykrikoides(Dinophyceae)에서 분비되는 유기물질의 특성 (Characteristics of Organic Substances Produced from Cochlodiniumpolykrikoides (Dinophyceae))

  • 강양순;권정노;안경호
    • ALGAE
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    • 제21권2호
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    • pp.253-259
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    • 2006
  • Organic substances are released from phytoplankton cells during all phases of growth. The type and amounts of organic substance excreted and the effects of nutrient limitation are often highly species-specific. Dinoflagellate, Cochlodinium polykrikoides grown in batch culture produced an exopolysaccharide. Exopolysaccharide and intracellular polysaccharide concentrations increased as C. polykrikoides cultures progressed from exponential phase, through stationary phase, to declining phase. In the exponential phase, the concentration of exopolysaccharide was relatively low, but in the stationary phase, it showed a rapid increase which seemed to coincide with the depletion of nitrate from the medium. Of the 20 amino acids analyzed, proline dominated in the organic matter of all cultures ranging from 48.2 to 79.9 nmol L–1, and constituting the 20-90% of total amino acids, and followed by histamine varying from 0.7 to 47.5 nmol L–1. Leucine and cysteine were also abundant in the stationary phase. The release rates of exopolysaccharide and intracellualr polysaccharide were higher the end of stationary phase than in the exponential phase. Exopolysaccharide concentration per cell was more than two times higher during the end of stationary phase than that in exponential phase. C. polykrikoides produced extracellular polysaccharide at a rate of 47.04 pg cell–1 day–1.

비음용 지하수 오염물질 기준설정체계 구축 연구: (1) 특정유해물질 (Establishment of Non-Drinking Groundwater Quality Standards: (1) Specific Harmful Substances)

  • 안윤주;남선화;이우미;윤성지;윤진열;정승우;김혜진;김현구;김태승
    • 대한환경공학회지
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    • 제35권9호
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    • pp.630-635
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    • 2013
  • 비음용 목적의 지하수에 대한 국내 수질기준은 기준항목 및 기준치설정에 근거가 명시되지 않아 체계적인 기준설정체계 마련이 시급한 실정이다. 본 연구에서는 비음용 목적의 특정유해물질에 대한 위해성기반 한국 지하수 수질기준 설정체계를 마련하기 위해 흡입 및 피부접촉 노출경로를 고려한 위해성을 반영하고 있는 선진국의 지하수기준 설정근거를 분석하였으며, 국내 타 수질 관련 매체의 기준 설정 체계를 바탕으로 향후 한국 지하수기준의 설정체계를 제안하였다 모니터링 우선항목 선정, 모니터링 수행, 위해성평가, 지하수 수질기준 후보물질 선정, 특정유해물질 지하수 수질기준 신규항목 선정 및 항목별 기준치 설정 단계로 제안하였다.

슬라이딩아크 방전과 코로나 방전의 복합공정을 통한 유해물질 처리효율 개선에 관한 연구 (A Study on Combined Processes of Sliding Arc Plasma and Corona Dielectric Barrier Discharge for Improve the Efficiency Treatment of Harmful Substance)

  • 권우택;이우식
    • 한국화재소방학회논문지
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    • 제28권6호
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    • pp.108-113
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    • 2014
  • 유해물질처리를 효율적으로 개선하기 위해 슬라이딩아크방전(sliding arc plasma)과 corona dielectric barrier discharge(CDBD공정)의 복합공정을 이용하였다. 이장치는 OH 라디칼과 음이온을 생성하여 강력한 산화력으로 탈취 및 살균 효과를 가진다. 실험결과 SAP 반응기의 크기를 80 A를 50 A로 축소하여도 유해물질의 농도는 큰 변화가 없는 것으로 나타나 반응기의 규모를 최소화할 수 있을 것으로 판단된다. 그리고 CDBD 반응기에서 생성된 음이온과 오존은 유해물질과 반응한 후 음이온은 510,000 ppb에서 470 ppb, 오존은 98 ppb에서 22 ppb로 낮아짐을 확인하였다. 또한 플라즈마 발생장치의 안정성 및 내구성이 우수한 것으로 판단되었다. 따라서 본 연구를 통하여 향후 플라즈마복합공정을 이용하여 실내공기중에 존재하는 유해물질 제거를 효율적으로 할 수 있을 것으로 생각된다.

음용 및 비음용 지하수 우선관리대상 항목 선정기법: CROWN (Chemical Ranking of Groundwater PollutaNts) (Chemical Ranking and Scoring Methodology for the Drinking and non-drinking Groundwater pollutants: CROWN (Chemical Ranking of Groundwater PollutaNts))

  • 안윤주;이우미;정승우
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권1호
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    • pp.16-25
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    • 2013
  • The Korean groundwater law regulates 20 groundwater contamination parameters, including 14 specific harmful substances. Expanding the number of groundwater quality standards are needed to cope with recent groundwater quality deterioration due to the use of various chemicals. Chemical ranking and scoring system (CRS) is a scientific tool to sort priority chemicals by considering exposure and toxicity potentials. In this study, we developed a CRS for scoring and ranking of possible groundwater pollutants and screened priority substances to be later considered in the Korean standard expansion. Chemical Ranking Of groundWater pollutaNts (CROWN) incorporates important parameters consisting of exposure potential, human and water ecotoxicity, interests, and certainty. Furthermore, CROWN additionally evaluated existence of other media standards to consider impacts by contamination of other media. The 197 substances that were common to 9 countries were selected first. CROWN evaluated and ranked each chemical, and finally suggested priority substances. Suggested priority substances were classified into two groups according to the groundwater use purposes: drinking and non-drinking. The priority substances were further classified into $1^{st}$ and $2^{nd}$ group priorities. The $1^{st}$ group consists of 75 substances, including the all the Korean groundwater standard parameters. CROWN will be used in selecting groundwater pollutants for possible inclusion in the Korean standard expansion.

Fast Screening of Harmful Disinfectants in Household Products via Low-Temperature Plasma Ionization-Mass Spectrometry

  • Lee, Hyoung Jun;Kweon, Gi Ryang;Yim, Yong-Hyeon
    • Mass Spectrometry Letters
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    • 제8권2호
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    • pp.44-47
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    • 2017
  • Isothiazolinone derivatives are widely used in consumer products as disinfectants or preservatives, but there are growing concerns about their impact on human health. Therefore, rapid screening of these biocides is very important for proper control and regulation of potentially hazardous substances. To this end, low-temperature plasma (LTP) ionization mass spectrometry (MS) was investigated to demonstrate its potential for direct and selective analysis of isothiazolinones from sprayed aerosol samples. Benzisothiazolinone (BIT) was clearly identified from a commercial fabric deodorant using LTP ionization MS and MS/MS. LTP allowed selective ionization of BIT directly from the simply sprayed aerosol sample and illustrated its potential for fast screening without sample pre-treatments. Selective nature of LTP ionization, on the other hands, implicates use of LTP ionization MS as a general screening method for specific groups of hazardous chemicals in commercial products.

활성물질을 사용하는 선박평형수 처리장치의 IMO 승인 절차 고찰 (Consideration of the Procedure for IMO Approval of Ballast Water Treatment System that Make Use of Active Substances)

  • 김은찬
    • 한국해양환경ㆍ에너지학회지
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    • 제11권4호
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    • pp.214-220
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    • 2008
  • 선박평형수 관리 협약에서 활성물질을 사용하는 선박평형수 처리장치는 IMO가 제정한 절차에 따라 IMO로부터 승인을 받아야하는 것으로 되어 있다. 협약에서 활성물질이란 유해 수중 생물과 병원균에 대하여 바이러스나 균류를 포함한 일반적인 또는 특정한 작용을 하는 물질 또는 생물을 말한다고 되어 있다. IMO 해양환경 보호위원회에서는 2008년 10월까지 13개의 선박평형수 처리장치에 기본승인을 부여하였고 4개의 처리장치에 최종승인을 부여하였다. 본 논문에서는 "활성물질을 사용하는 선박평형수 관리시스템의 승인을 위한 절차서(G9)"와 "GESAMP-BWWG의 정보 수집과 업무 수행을 위한 방법"에 근거하여 기본승인과 최종승인의 절차와 문서의 요소를 고찰하였고, IMO로부터 기본승인 또는 최종승인을 받은 처리장치의 승인 내용을 요약하였으며, 이로부터 몇 가지 문제점을 제기하였다.

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The Trend of Cigarette Design and Tobacco Flavor System Development

  • Wu, Jimmy Z.
    • 한국연초학회지
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    • 제24권1호
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    • pp.67-73
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    • 2002
  • In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

야자계 활성탄을 활용한 폼 복합체의 미세기공 구조특성 (Characteristics of Micro-pore Structure of Foam Composite using Palm-based Activated Carbon)

  • 최영철;유성원
    • 한국구조물진단유지관리공학회 논문집
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    • 제25권5호
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    • pp.157-164
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    • 2021
  • 최근 미세먼지와 관련된 환경문제를 개선하기 위해 유해물질을 제거할 수 있는 광촉매와 흡착제에 대한 연구가 활발히 진행되고 있다. 본 연구에서는 전체 공극량이 일반 건설재료에 비해 상당히 큰 폼 콘크리트에 다량의 마이크로 공극를 갖는 야자계 활성탄소를 이용해서 다공성 폼 복합체를 제작하였다. 미세먼지 흡착 가능성을 평가하기 위해 제작된 폼 복합체에 대해 공극 구조를 분석하였다. 폼 복합체의 공극구조 분석은 측정된 질소 흡착등온선으로부터 BET와 Harkins-jura이론을 적용하였다. 분석결과 활성탄소를 혼입한 폼 복합체의 비표면적과 마이크로 공극 부피가 Plain보다 크게 증가하였다. 활성탄소 혼입율이 증가할수록 폼 복합체의 비표면적과 마이크로 공극 부피가 증가하는 경향을 나타냈다. 이는 폼 복합체가 가스상의 미세먼지 전구물질 NOX에 대한 흡착성능이 높을 것으로 보인다.

사용자 실천 중심 의복지속가능성 평가항목 개발 (Development of Evaluation Criteria for Fashion Sustainability Focused on User Practice)

  • 김인혜;하지수
    • 한국의류산업학회지
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    • 제23권2호
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    • pp.174-185
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    • 2021
  • The purpose of the study is to establish sustainability evaluation items that can be applied to enhance clothing sustainability practice. The sustainability evaluation items related to clothing by product category, use, and disposal were derived through literature review. In order to evaluate the validity of the derived evaluation items, preliminary survey and two questionnaires were conducted for experts, and the importance and the possibility of change were measured. As a result, 39 evaluation items were constructed. Among the 39 evaluation items, 26 items related to the use and disposal were evaluated for 10 weeks in the 20s and 30s female consumers in terms of practice. The results of the study are as follows: First, items that have a high degree of importance and possibility of change are the items that can minimize resource saving, recycling, and the emission of harmful substances. Second, the participants' perceptions, attitudes, and outcomes of practicing the evaluation items of the use and disposal phase were proved to be positively affected, and the possibility of reducing resource saving and environmental impacts was proved. The clothing sustainability practice played a positive and developmental role in real life, while changing from small things to pursuing newness. The vagueness of sustainability was changed to specific perceptions and behaviors through the practice of the evaluation items.