• 제목/요약/키워드: CARB

검색결과 42건 처리시간 0.02초

HC저감용 최적 연료분사 시스템에 관한 연구 (A Study on the Fuel Injection System for Optimizing Reduction of HC Emission)

  • 이기형;이창식
    • 한국자동차공학회논문집
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    • 제3권2호
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    • pp.146-156
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    • 1995
  • Growing international concern about environmental issues in recent years has led to new proposals for strengthening exhaust emission standards and fuel economy requirements throughout the world. The low emission vehicle(LEV) standards drawn up by the California Air Resources Board(CARB) in the U.S.A are noticeably stringent To cope with this regulation, a reduction of HC emission is the most important challenge for the automotive industry because HC emission levels are severer than any other components emission levels. In this paper, the apparatus for visulalizing the wall film flow in a intake manifold and the spark plug with optical fiber for detecting the signal from diffusion flame are developed to mal,e the HC formation mechanism clear. High speed camera system is also used to elucidate the correlation wall film flow and the diffusion flame. Using these methods, the effect of fuel injection systems such as injection direction, spray angle, atomised injection on HC emission levels is investigated. Consequently, the optimal fuel injection conditions for minimizing the wall film flow and reducing the HC emission are found through this research.

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실험실에서 사육된 눈콩게 Scopimera bitympana(달랑게과)의 유생발생 (The Complete Larval Development of a Sand Bubbler Crab, Scopim era bitympana Shen(Brachyura, Ocypodidae),Reared in the Laboratory)

  • 장인권;김창현
    • 한국동물학회지
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    • 제33권2호
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    • pp.200-216
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    • 1990
  • 실험실에서 사육된 눈콩게의 전 유생발생단계를 기술, 도시하였다. 눈콩게는 5 zoea(가끔 6 zoea)와 1 megalopa유생기를 가졌다. 수온 $25^{\circ}C$에서, megalopa와 제1기 carb 부화후 각각 24일과 38일만에 나타났으나 extra zoea유생기를 갖는 경우에는 31일과 48일만에 나타났다. 눈콩게의 zoea유생 거치상의 갑각가시와 배측에 하나, 복측에 두 개의 작은 가시가 있는 미절에 의하여 엽낭계속의 타종과 구분되며, megalopa 유생은 갑각의 특징에 의하여 구분될 수 있다. 그 밖의 미세한 형태적 특징들이 앞서 보고된 엽낭개속의 유생들과 비교되어 차이점이 간단히 논의되었다.

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E. coli pRDI에서의 DAP-영양요구성 변이주 분리 및 동정 (Isolation and Identifition of DAP-Auxotrophs from E. coli pRDI)

  • 이호자
    • 미생물학회지
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    • 제22권4호
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    • pp.265-269
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    • 1984
  • E. coli $P^{RDI}$에서 DAP-영양요구성 변이주를 분리하였으며 이 변이주가 갖고 있는 plasmid의 안정성과 활성도를 확인하는 살험을 통하여 다음과 같은 결론을 얻었다. 1. Mutagen인 NG를 처리 후 DAP-변이주를 보다 쉽게 분리하기 위하여 항생제처리를 하였다. 이때 사용균주가 갖고 있는 plasmid내의 내성인자들 중에 carbr인자로 인하여 같은 계열에 있는 penicillin유도체들에 대해서는 교차내성을 갖고 있음이 확인되었다. 그러냐 penicillin과 같은 기능을 갖고 있으나 그 구조가 다른 cephalexin, cycloserine에 대해서는 교차 내성을 잘 나타내지 않았으므로 항생제처리로서는 cephalexin을 사용하였다. 2. 세균 접합을 통하여 DAP-균주의 특성을 동정하였다. 즉 nif-gene의 안정성과 활성도는 DAP-균주로 부터 plasmid를 전이반은 전이체에서 6-cyanopurine첨가로 확인하였다.

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3-[(4-카르복시-5-레틸티오이소티아졸-3-일)옥시메틸] 세파로스포린 유도체들의 합성 및 항균력에 관한 연구 (A Study on the Synthesis and Antibacterial Activities of 3-[(4-Carboxy-5-ethylthioisothiazo1-3-yl) oxymethyl] cephalosporin Derivatives)

  • 최원식;박의석;박규종;이영행
    • 약학회지
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    • 제44권2호
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    • pp.155-161
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    • 2000
  • New cephalosporin antibiotics , 3-[(4-carboxy-5-ethylthioisothiazol-3-yl)oxymethyl]-7-[(1H-tetra-zol-1-yl)acetamido]-3-cephem-4-carboxylic acid 2, 3-[(4-carboxy-5-ethylthioisothiazol-3-yl) oxymethyl]-7-[(2-aminothiazol-4-yl)acetamido]-3-cephem-4-carboxylic acid 3, 3-[(4-carb oxy-5-ethylthioisothiazol-3-yl)-oxymethyl]-7-[5-(ethylthio-3-hydroxyisothiazol-4-yl)carboxamido]-3-cephem-4-carboxylic acid 4, 3-[(4-car-boxy-5-ethylthioisothiazo1-3-yl)oxymethy1]-7-[(Z)-2-(fur-2-yl)-2-(methoxyimino)acetamido]-3-cephem-4-carboxylic acid 5, 7-[(Z)-2-(2-aminothiazol-4-yl)-2-[(alkoxyimino)acetamido]-3-[(4-carboxy-5-ethylthioisothiazol-3-yl)oxymethyl]-3-cephem-4-carboxylic acid 6-8 were synthesized. Antibacterial activities and structure-activity relationships of these new cephalosporin derivatives were examined. Among them, 7-[(Z)-2-(2-aminothiazol-4-yl)-2-(1-carboxy-1-methylethoxyimino)acetamido]-3-[(4-carboxy-5-ethylthylth-ioisothiazol-3-yl)oxymethyl]-3-cephem-4-carboxylic acid 7 exhibited good antibacterial activities compared to cefotaxime and ceftriaxone.

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Self-Diagnostic Signal Monitoring System of KWP2000 Vehicle ECU using Bluetooth

  • Choi, Kwang-Hun;Lee, Hyun-Ho;Lee, Young-Choon;Kwon, Tae-Kyu;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.132-137
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    • 2004
  • On-Board Diagnostic(OBD) systems are in most cars and light trucks on the load today. During the 1970's and early 1980's manufacturers started using electronic means to control engine functions and diagnose engine problems. The CARB's diagnostic requirements to meet EPA emission standards have been designated as OBD with a goal of monitoring all of the emissions-related components, as well as the chassis, body, accessory devices and the diagnostic control network of the vehicle for proper operation. In this paper, we present a remote measurement system for the wireless monitoring of diagnosis signal and sensors output signals of ECU adopted KWP2000, united the OBD communication protocol, on OBD-compliant vehicle using the wirless communication technique of Bluetooth. In order to measure the ECU signals, the interface circuit is designed to communicate ECU and designed terminal wirelessly according to the ISO, SAE regulation of communication protocol standard. A microprocessor S3C3410X is used for communicating ECU signals. The embedded system's software is programmed to measure the ECU signals using the ARM compiler and ANCI C based on MicroC/OS kernel to communicate between bluetooth modules using bluetooth stack. The diagnostic system is developed using Visual C++ MFC and protocol stack of bluetooth for Windows environment. The self-diagnosis and sensor output signals of ECU is able to monitor using PC with bluetooth board connected in serial port of PC. The algorithms for measuring the ECU sensor output and self-diagnostic signals are verified to monitor ECU state. At the same time, the information to fix the vehicle's problem can be shown on the developed monitoring software. The possibility for remote measurement of self-diagnosis and sensor signals of ECU adopted KWP2000 in embedded system verified through the developed systems and algorithms.

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게껍질의 급여가 우유내 타우린함량에 미치는 영향 (Effect of Crab Shell Supplementation in Feeds on Taurine Content of Cow s Milk)

  • 박태선;박동진;이지선;김동신
    • 한국식품영양과학회지
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    • 제29권6호
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    • pp.1075-1082
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    • 2000
  • 본 논문에서는 게껍질분말 급여에 의한 천연 타우린 강화우유의 생산 가능성을 평가하고자 25두의 젖소를 5군으로 나누고, 각기 대조사료, 1%(1%CS), 3%(3%CS) 및 5% 게껍질분말사료(5%CS), 그리고 formaldehyde로 처리되 3% 게껍질분말사료 (3%FCS)를 30일간 급여하였다. 게껍질분말 단백질의 아미노산조성은 phenylalanine이 가장 높았고, glutamate, aspartate, glycine, serine histidine, arginine의 순으로 나타났으며, 다른 동물조직의 단백질과는 달리 branched-chain 아미노산의 함량이 비교적 낮았다. 게껍질에 함유된 유리아미노산 중 타우린은 가장 고농도로 존재하였으며, 특히 집게다리껍질에 509$\mu$mol/100 g이 함유되어 등뚜껑(319$\mu$mol/100g) 및 게껍질분말(296 $\mu$mol/100 g)에 비해 월등히 그 함량이 높았다. 게껍질분말의 급여가 우유의 타우린농도에 미치는 영향을 평가한 결과 p<0.01 수준에서 유의성이 관찰되었다. 1%CS군의 원유에는 5.84$\pm$0.73 $\mu$mole/100mL의 타우린이 함유되어 대조구 (4.84$\pm$0.29 $\mu$mol/100mL)에 비해 20%정도 더 높았으며, 3%CS군의 원유에는 7.21$\pm$0.77$\mu$mole/100 mL의 타우린이 함유되어 대조구에 비해 49%정도 유의적으로 증가하였다.(p<0.01). 한편, 3%FCS군의 경우 원유의 타우린농도가 3%CS군에 비해 유?거으로 감소하였고, 따라서 게껍질의 formaldehyde 처리는 반추위내에서 타우린을 보호하는데 효과적이지 못한 것으로 나타났다. 본 논문은 게껍질 급여에 의해 우유의 타우린농도가 증가하였음을 밝히는 최초의 보고이며, 본 연구의 결과는 앞으로 기타 축산제품의 타우린함량을 증가시키는데 폭넓게 응용되어질 수 있을 것이다.

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키토산 비드에 의한 중금속 이온의 고정층 흡착에 관한 연구 (A Study on the Fixed-bed Adsorption of Heavy Metal Ions over Chitosan Bead)

  • 정경환
    • 공업화학
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    • 제10권1호
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    • pp.166-172
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    • 1999
  • 폐수중 중금속 이온을 제거하기 위한 방법으로 키토산 비드에 의한 금속 이온의 고정층 흡착 특성을 조사하였다. 게껍질로부터 키틴을 추출하고 이를 탈아세틸화 반응시켜 키토산을 제조하였다. 키토산은 비드로 만들어 중금속 흡착제로 사용하였다. 키토산 비드에 대한 $Cu^{2+}$, $Co^{2+}$, $Ni^{2+}$ 이온의 단성분 평형 흡착 실험 결과로부터 Freundlich와 Langmuir 흡착등온식을 결정하였다. 흡착등온식에 의하면 키토산 비드에 대한 중금속 이온의 흡착 세기는 $Cu^{2+}$>$Co^{2+}$>$Ni^{2+}$의 순서로 나타났다. 키토산 비드에 대한 중금속 이온의 단성분 또는 다성분계 고정층 흡착 실험으로부터 흡착 파과곡선을 구하였다. 단성분 흡착등온식으로 다성분 흡착 평형을 예측할 수 있는 IAS (ideal adsorbed solution) 이론을 적용하여 LDFA (linear driving force approximation)에 의한 고정층 흡착 모델식을 수치해 기법으로 모사하여 실험결과와 비교하였다. LDFA에 의한 모델식을 적용한 결과 키토산 비드에 대한 중금속 이온의 단성분 및 다성분계 고정층 흡착거동을 잘 모사할 수 있었다.

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차광처리에 따른 수리취의 광합성 관련 특성 변화 (Changes of Characteristics Related to Photosynthesis in Synurus deltoides under Different Shading Treatments)

  • 이경철;노희선;김종환;안수용;한상섭
    • 한국약용작물학회지
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    • 제20권5호
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    • pp.320-330
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    • 2012
  • This study was conducted to investigate the changes of chlorophyll contents, chlorophyll fluorescence, photosynthetic parameters, and leaf growth of Synurus deltoides under different shading treatments. S. deltoides was grown under non-treated (full sunlight) and three different shading conditions (Shaded 88~93%, 65~75%, and 45%~55%). Light compensation point ($L_{comp}$), dark respiration ($D_{resp}$), maximum photosynthesis rate ($Pn_{max}$), photo respiration rate ($P_{resp}$), carboxylation efficiency ($\Phi_{carb}$), and photochemical efficiency were decreased with increasing shading level; However, $CO_2$ compensation point ($CO_{2\;comp}$), total chlorophyll content, and specific leaf area (SLA) were shown the opposite trend. S. deltoides under 88~93% treatment showed the lowest photosynthetic activity such as maximum photosynthetic rate ($Pn_{max}$), photochemical efficiency, and $CO_2$ compensation point ($CO_{2\;comp}$). Therefore, photosynthetic activity will be sharply decreased with a long period of 8~12% of full sunlight. With the shading level decreased, carotenoid content and non-photochemical fluorescence quenching (NPQ) increased to prevent excessive light damage. This result suggested that growth and physiology of S. deltoides adapted to high light intensity through regulating its internal mechanism.

새로운 카바페넴계 항생물질인 DWP20418의 In vitro 항균작용 (In vitro Antibacterial Activity of DWP20418, a New Carbapenem Antibiotic)

  • 김지연;최문정;박남준;임성수;변영석;유영효;박명환
    • 약학회지
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    • 제41권2호
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    • pp.233-240
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    • 1997
  • The in vitro antibacterial activity of DWP20418 (1R, 5S, 6S)-6-[1-(R)-Hydroxyethyl)-l-methyl-2-[(2S,4S)-2-(piperazinylcarbonyl)-1-(R)-hydroxyethyl)pyrrolidine-4-thio]carb apen-2-em-3-carboxylic acid), a new carbapenem antibiotic, was compared with those of imipenem (IPM) and meropenem (MEPM). DWP20418 was comparable or slightly more superior to MEPM against gram-positive bacteria, and it showed more potent activity to IPM against gram-negative bacteria. DWP20418 was particularly active against MRSA, and its $MIC_{90}$ of methicillin-susceptible S. aureus, low methicillin-resistant S. aureus and high methicillin-resistant S. aureus were 0.391, 25 and 50 ${\mu}g/ml$, respectively. With a view of $MIC_{90}$, DWP20418 was comparable than the other carbapenems against P. aeruginosa and E. coli isolates. The activity of DWP20418 was not affected in the presence of $Mg^{2+},\;Ca^{2+}$ or horse serum. But inoculum size and alterations in pH of medium affected its antibacterial activity. DWP20418 showed rapidly bactericidal activity within 1h, and regrowth was not observed even incubation of 24hrs at the concentrations near the MIC.

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A STUDY ON A CATALYTIC CONVERTER OBD BEFORE LIGHT-OFF

  • Yun, Seung-Won;Son, Geon-Seog;Lee, Kwi-Young
    • International Journal of Automotive Technology
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    • 제3권1호
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    • pp.33-40
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    • 2002
  • Increasingly stringent emission regulations of EU and CARB (California Air resource Board) require mandatory OBD (On Board Diagnostics) far the catalytic converters of a vehicle. It demands that MIL(Malfunction Indication Light) should be tuned on to inform the driver of catalytic converter failures. Currently dual oxygen sensor method Is widely used for the converter OBD. However, since it works only alter converter light-off, it has a serious limitation when applied to TLEV or more stringent emission regulations where more than 85% of total emission is coming out before converter light-off. In addition, a recent development in catalyst material. coating technology and additive catalysts leads to a much improved OSC (Oxygen Storage Capacity) after converter light-off, current methods are very difficult to determine levels of converter aging. Therefore, it is desired to develop an OSC detecting method before converter light-off to diagnose converter failures with higher reliability. In this study, OSCs of converters are measured by an absolute measuring method and a dynamic measuring method, and some of fundamental ideas are suggested about converter OBD before converter light-off. The converters are aged with two different aging methods; those are a furnace aging and an engine bench aging: to represent aging conditions in actual field applications. Dual oxygen sensor method at the lower temperature than light-off is also studied at a model gas bench with the converters. It is fecund that there is a certain point in temperature lower than light-off where difference due to aging level becomes maximum, thus a proper dynamic method to effectively monitor catalytic converters could be implemented fur the range lower than light-off temperatures. With this result, the aging level of converters is examined at an engine bench.