• Food Science and Biotechnology
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• 제17권3호
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• pp.669-674
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• 2008

Zanthoxylum schinifolium and Zanthoxylum piperitum A.P. DC. belong to the Rutaceae family and are perennial, aromatic, and medicinal herbaceous plants. In this study, their aroma compounds were isolated by steam distillation extraction using a Clevenger-type apparatus, and then further analyzed by gas chromatography (GC) and gas chromatograph/mass spectrometry (GC/MS). The yields of the essential oils from Z. schinifolium and Z. piperitum AP. DC. were 2.5 and 2.0%(w/w), respectively, and the color of their oils was quite similar, a pale yellow. From the distilled oil of Z. schinifolium, 60 volatile compounds which make up 87.24% of the total composition were tentatively identified, with monoterpenes predominating. $\beta$-Phellandrene (22.54%), citronellal (16.48%), and geranyl acetate (11.39%) were the predominantly abundant components of Z. schinifolium. In the essential oil of Z. piperitum AP. DC., 60 volatile flavor components constituted 94.78% of the total peak area were tentatively characterized. Limonene (18.04%), geranyl acetate (15.33%), and cryptone (8.52%) were the major volatile flavor compounds of Z. piperitum A.P. DC.

• 한국환경과학회지
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• 제3권4호
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• pp.373-380
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• 1994

Volatile organic compounds in the ambient air were gathered irregularly by normal temperature concentrating method at Odea-ri and Oceon-ri Ulsan-gun in the neighbourhood of Ulsan Petrochemical Industrial Complex and analyzed with gas chromatograph. Several hydrocarbons in common aklospheric air or emitted fugitively from the chemical plants were identified and quantified by comparison with the retention times of standard compounds. The results from several field surveys in 1992 show that the concentrations of styrene at residential area of Odea-ri and Ocheon-ri were less than 0.4 ppm, but once a while greater within the chemical plants area. When it smelled unpleasantly in these area, the concentration of hydrocarbons were also high. It was concluded that the close and long-term investigation about other odorous components but hydrocarbons will be necessary to ascertain the cause of unpleasant odor of these area.

• Food Quality and Culture
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• 제1권1호
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• pp.13-17
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• 2007

The volatile flavor compounds of Saussurea lappa C.B. Clarke, a perennial, aromatic and medicinal herbaceous plant of the Asteraceae family, were isolated by the hydro distillation extraction method using a Clevenger-type apparatus, and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The plant yielded a light yellow colored oil (0.02%, v/w). From S. lappa C.B. Clarke root oil, sixty-three volatile flavor compounds were tentatively identified, among which sesquiterpene was predominant (21.70%). The identified compounds of the root oil constituted 87.47% of the total peak area. From the constituents making up more than 5% of the volatile flavor components, a long-chain aldehyde, (7Z, 10Z, 13Z)-7, 10, 13-hexadecatrienal, was the most abundant volatile flavor compound (21.20%), followed by dehydrocostuslactone (10.30%) belonging to sesquiterpene lactone, valerenol (5.30%) and vulgarol B (5.06%).

• 한국연소학회지
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• 제14권1호
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• pp.19-24
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• 2009

A novel low NOx oil burner of 0.7 MW (for a 1 ton steam/hr industrial boiler) was designed and tested to investigate the combustion characteristics through in-flame measurement and flue gas analysis. Flame shape was observed by CCD camera and $CH^*/{C_2}^*$ radical distribution in the flame were observed, along with measurement of flue gas composition such as NOx and CO, for various heat inputs, excess airs and pressure of the fuel spary nozzles. The flame showed the two-zone structure: fuel-rich and fuel-lean zone, which was very favorable for the low-NOx combustion, and the NOx emission for haevy oil combustion was significantly reduced to < 150 ppm at 4 % $O_2$, compared with the NOx level of a conventional heavy oil burner.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.633-636
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• 2006

GE has developed a plastic substrate technology comprised of a superior high-heat polycarbonate substrate film and a unique transparent coating package that provides the ultrahigh barrier to moisture and oxygen, and chemical resistance to solvents used in device fabrication. This contribution will update recent progresses made at GEFlexible Ultra-high Gas Barrier Substrate for Organic Electronics on ultra-high barrier coated plastic substrate, both in batch mode and in roll-to-roll mode

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.520-525
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• 2000

This research is to analyze the ventilation performance of mechanical ventilation systems for indoor air quality control and management. A ventilation performance with supply sites is evaluated in a test model chamber and office room. A $CO_2$ gas as a tracer gas is used to measure the ventilation performance. The ventilation performance is found to increase with increased the ventilation rate. The ventilation performance is analysed with 55% at the supply air of 570 lpm and with 20% at the supply air of 100 lpm in a test chamber. The ventilation performance is better than 15% comparing with natural decay at the supply of 570 lpm in office room.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.837-841
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• 2001

Almost all power plant boiler has temperature distribution nonuniformity problem in heat transfer tube flow path. It can cause hot spot damage of superheated or reheated heat transfer section and reduce maintenance schedule when nonuniformity is severe. There are two solutions for improvement temperature nonuniformity. one is change of gas flow distribution of gas path and the other is contorl steam flow in tube bank. Of course, first method is very difficulty to apply but second method is'nt. In this paper, control steam flow is used to solve temperature nonuniformity of power plant boiler.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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• pp.103-105
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• 2009

본 연구에서 우리는 single walled carbon nanotube(SWNT) 용액 속의 TEOS와 VTMS 바인더가 나노튜브 센서의 감도의 증가와 선택성을 가지는 것에 대해서 조사하였다. 일반적으로 혼합된 SWNT 용액 속의 유기 화합물인 바인더는 기판에 잘 부착된다. 그리고 가수분해 된 바인더의 표면에는 바인더가 경화 되었을 때 기능화 된 하나의 그룹이 형성된다. 그것은 SWNT의 표면에 가수분해 된 TEOS와 VTMS의 -OH와 $-CH=CH_2$ 같이 기능화된 그룹이다. 그러므로 전하는 carbon nanotube와 흡착된 분자 사이에서 이동되고 그에 대한 영향으로 전기적인 전도성이 변화한다. 이 실험에서 증가되어지는 알콜 농도에 따라 TEOS 바인더를 사용한 센서의 저항은 감소하는 반면 VTMS 바인더를 사용한 센서의 저항은 증가한다.

• 연구논문집
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• 통권26호
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• pp.43-50
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• 1996

Present paper describes on/off design performance analysis of an 74KW industrial turboshaft gasturbine engine. Procedures to match between the compressor, combustor and turbine have been incorporated into the developed program satisfying compatibility requirement of flow and work and ratational speed. The validity of the performance results from the developed program are yet to be proved through performance experiments of the resultant engine, but comparison of the present results with those from "GASCAN(Thermoflow:America) under similar mass inlet flow, pressure ratio, and speed condition show good agreement despite present results underpredict 6-10% for power and up to 3% in efficiency, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.86-87
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• 2005

Aluminum(Al) sputtering is best known method to form Al film for the Si wafer in the process of 180nm and above. In the Al metal line process, one of the frequently founded and well-known defect was metal depression. In this paper, several experiments were performed such as temperature, Ar gas flow rate, thickness change in other to reduce the metal depression and find the origination of metal depression. Through experiments, it is found that metal depression was significantly related to the temperature. And the Ar gas flow rate did not influence to the creation of depression. The off status ESC also showed stable metal film without depression by same mechanism of temperature decrease. Also, thickness is strongly influence to the metal depression.