• 생약학회지
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• 제35권4호통권139호
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• pp.276-282
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• 2004

This study has been conducted to investigate the amount of residual sulfur dioxide for herbal medicines of 30 species which are purchased in 13 different regions (Bonghwa, Busan, Chunju, Jecheun, Kwangiu, Keumsan, Seoul, Taeku, Cheungdu, Xian, Beijing, Tokyo and Osaka). The sulfur dioxide residues were determined in the collected 386 samples by the modified Monier-Williams method. The residues of sulfur dioxide in 386 samples ranged from ND (under detection limit) to 2808 ppm. The sulfur dioxide in Cassiae Semon, Cinnamomi Ramulus, Cervi Cornu, Hoelen, Crataegi Fructus, Artemisiae Argyi Herba, Scolopendrae Corpus, Schizandrae Fructus and Cyperi Rhizoma were detected under the detection limit regardless of the collected regions. The sulfur dioxide residues in herbal medicines collected in domestic regions were relatively lower than those in foreign regions. There are no standards for sulfur dioxide residual limits of herbal medicines in Korea. This results will provide the scientific basis for the standardization of sulfur dioxide residues in Korea Pharmacopoeia.

• Bulletin of the Korean Chemical Society
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• 제25권1호
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• pp.73-78
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• 2004

A highly sensitive detecting method has been developed for determining part per billion of sulfur in $H_2S$/Ar plasma. The method is based on the excitation of Ar/$H_2S\;or\;Ar/H_2S/O_2$ mixture in hollow cathode glow discharge sustained by radiofrequency (RF) or 60 Hz AC power and the spectroscopic measurement of the intensity of emission lines from electronically excited $S_2^*\;or\;SO_2^*$ species, respectively. The RF or AC power needed for the excitation did not exceed 30 W at a gas pressure maintained at several mbar. The emission intensity from the $SO_2^*$ species showed excellent linear response to the sulfur concentration ranging from 5 ppbv, which correspond to S/N = 5, to 500 ppbv. But the intensity from the $S_2^*$ species showed a linear response to the $H_2S$ only at low flow rate under 20 sccm (mL/min) of the sample gas. Separate experiments using $SO_2$ gas as the source of sulfur demonstrated that the presence of $O_2$ in the argon plasma is essential for obtaining prominent $SO_2^*$ emission lines.

• 한국대기환경학회지
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• 제30권6호
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• pp.545-554
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• 2014

In general, odorant was added to fuel gases, such as LPG, LNG and city gas, to prevent gas poisoning, ignition, explosion, or other accident caused by fuel gases, and to enable immediate and easy detection of fuel-gas leakage by emitting an offensive smell. This study describes a study on the exhaust emissions characteristics and fuel economy of liquefied petroleum gas (LPG) vehicle using LPG fuel with new sulfur free odorant. New sulfur free odorant was added to LPG to reduce sulfur content of the LPG. Its performance and exhaust emission were compared to those of LPG with sulfur containing odorant (EM, ethyl mercaptan). Engine performance using LPG with sulfur free odorant was similar to that with sulfur-containing odorant. Exhaust emissions from the LPG vehicle with LPG including sulfur free odorant were also similar to those with LPG including sulfur containing odorant in the FTP 75 and NEDC mode. There experimental results suggest that the sulfur free odorant may substitute for the sulfur containing odorant in LPG fuel.

• 한국대기환경학회지
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• 제13권5호
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• pp.355-360
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• 1997

The atmospheric concentration of dimethylsulfide (DMS), known as the predominant volatile organic. sulfur compound, is determined at subnanogram level by a combined application of non-cryogenic preconcentration method and gas chromatography with flame photometric detection (GC/FPD). The volatile DMS in air is preconcentrated using a trapping tube containing adsorbent like Molecular Sieve 5A (or gold-coated sands). The tube is then connected to the GC/FPD system via a six-way rotary valve, thermally desorbed at 40$0^{\circ}C$, separated on OV101 column, and detected by a flame photometric detector. The DMS peak elutes at about 2.5 mins and is integrated electronically. The analytical precision, if expressed in terms of relative standard error, is around 5%. The detection limit of our GC/FPD system is ca 1 ng of DMS. Details of our analytical system are presented.

• 대한환경공학회지
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• 제32권6호
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• pp.555-562
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• 2010

수중의 독성을 탐지하기 위하여 황산화미생물을 이용한 새로운 형태의 생태독성탐지 방법이 연구되었다. 황산화미생물이 산소 존재 하에서 황입자를 산화하여 황산을 만들게 되고 이는 EC의 증가 및 pH의 감소를 가져온다. 독성물질이 들어오면 미생물의 저해로 황산을 적게 만들게 되므로 EC의 증가 정도가 감소하게 된다. 인공하천수(EC= 0.12 mS/cm and pH=7.2)를 이용하여 황산화미생물을 배양하고 반응조를 HRT 30분으로 연속 운전한 결과 유출 인공하천수의 EC=0.5~1.2 mS/cm, pH= ~2.5이었으며 7일 동안 일정하게 유지되었다. 이러한 유입수와 유출수의 EC의 차이는 인공하천수가 독성이 없는 조건에서 일정 속도로 황산을 만들었기 때문이다. 아질산성질소 2 mg/L를 함유한 인공하천수를 넣은 결과 인공하천수 주입 후 1.5시간 경과 후 EC 값이 급격하게 감소하고 pH 값은 상승하여 독성을 쉽게 탐지 가능하였다. 최적의 체류시간은 30분이었으며 이는 황입자의 크기를 줄임으로써 더 짧은 체류시간에서 운전이 가능할 것으로 판단된다.

• 분석과학
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• 제16권3호
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• pp.240-248
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• 2003

공업지역에서 악취원인물질로 잘 알려진 황화물은 매우 낮은 최소 후각감지농도를 나타낸다. 여러 악취발생원 주변의 대기 중 미량의 황화합물을 아르곤에서 농축시켜 선택성과 감도가 우수한 불꽃 광도 검출기 (FPD)가 장착된 가스크로마토그래프를 이용하여 측정하였다. 25% ${\beta}$,${\beta}$-Oxydipropionitrile, 60/80 Chromosob W가 저온농축을 위한 흡착제로 되었으며 이를 충전 유리컬럼의 충전제로도 사용하였다. 악취시료의 농축량은 0.1~3.0L 범위에서 채취장소에 따라 달리하였다. 주거지역과 사업장 부지경계선상에서의 공기 및 하수처리장과 같은 공업지역 내 사업장의 배출구 가스 중의 휘발성 황화합물의 농도를 측정하였다.

• 한국식품과학회지
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• 제37권5호
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• pp.695-701
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• 2005

각각의 황 함유 화합물의 표준곡선을 그렸을 때, linear range의 범위는 $10^2$부터 $10^4$까지의 범위를 보였다. Dimethyl trisulfide가 가장 작은 limit of detection(LOD) 값과 가장 넓은 linear range $(10^4)$를 보이는 반면, methional은 가장 큰 LOD 값과 가장 좁은 linear range$(10^2)$를 가졌다. 각 황 함유 화학물의 분자구조와 PFPD의 황 함유 화합물 분석 원칙에 영향을 받는 것으로 사료된다. 서로 다른 세 종류의 fiber를 사용시, 미세 고체상 추출법(SPME)을 사용했을 때, CAR/PDMS fiber는 가장 좋은 추출 효율을 보였고, 반대로 PDMS/DVB fiber는 가장 낮은 효율을 나타내었다. SPME 방법을 사용하면, 시료에 포함되어 있는 6개의 황 함유 화합물들 중, 최대 5개까지 분석이 가능하였다. 그러나 본 실험에서 사용하지 않은 황 함유 화합물들도 다수 동정 되었는데, 이렇게 추출과정 중 artifacts로 생성된 황 함유 화합물들은 분석 시 오차를 작용할 수 있다. 고정상 기체추출법(SH)은 SPME와 비교했을 때 더 적은 수의 황 함유 화합물을 감지해냈다. SPME와 비교 시 SH의 추출 효율은 낮았지만, artifact로 생성되는 화합물의 수는 적었다.

• 한국염색가공학회지
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• 제30권2호
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• pp.63-69
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• 2018

In this study, we report on successful attempt towards the synthesis of sulfur self-doped $g-C_3N_4$ by directly heating thiourea in air. The synthesized materials were characterized using UV-vis spectral technique, FT-IR, XRD and TEM analysis. Further, the obtained material shows an excellent detection of carcinogenic TNP(Tri nitro phenol) in the presence of 10-fold excess of various other common interferences. The strong inner filter effect and molecular interactions(electrostatic, ${\pi}-{\pi}$, and hydrogen bonding interactions) between TNP and the $S-g-C_3N_4$ Nano sheets led to the fluorescence quenching of the $S-g-C_3N_4$ Nano sheets with an excellent selectivity and sensitivity towards TNP compared to that of other nitro aromatics under optimal conditions and the detection limit calculated was found to be 6.324 nM for TNP. The synthesized nanocomposite provides a promising platform for the development of sensors with improved reproducibility and stability for ultra-sensitive and selective sensing of TNP.

• 한국대기환경학회지
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• 제21권2호
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• pp.269-274
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• 2005

In this work, analytical bias arising from the gas chromatographic determination of sulfur compounds was evaluated by the application of direct loop injection method to the GC/PFPD detection of four sulfur compounds including H$_{2}$S, CH$_{3}$SH, DMS, and DMDS. For the proper evaluation of analytical uncertainties involved in GC calibration, we employed two comparative techniques of calibration at fxed concentration injection (CFCI) vs calibration at fixed volume injection (CFVI) method. The results of our study indicate that CFCI method exhibits very poor sensitivity due to the matrix effect with varying injection volumes. On the other hand, as CFVI method overcomes such limitation, it can be used to obtain very accurate quantification of S compounds at their high concentration levels above a few to a few tens ppb.

• 한국약용작물학회지
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• 제21권2호
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• pp.124-129
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• 2013

This study was conducted to investigate the residual contents of sulfur dioxide ($SO_2$) in commercial medicinal herbs in Korea in 2012. Among a total of 136 samples of 16 different kinds of herbs, 86 samples (15 Kinds) were domestic, and 50 samples (14 Kinds) were imported. Sulfur dioxide in the samples was measured by a modified Monier-Williams method. Of the 136 samples, 17 samples (12.5%, 6 Kinds) failed to meet the regulations for sulfur dioxide residues of KFDA in medicinal herbs. Among 17 unsuitable samples, 7 samples (8.1%, 3 Kinds) were domestic, and 10 samples (20.0%, 6 Kinds) were imported. The highest amount of sulfur dioxide residues was 3,167.94 mg/kg (Lycii Fructus) in the domestic samples. The detection frequency of sulfur dioxide by medicinal herb parts used, Rhizoma 25.7%, Flos 20.0%. Cortex 12.5%, Radix 15.3%, Fructus 7.6%, p-value 0.011. This results will be used as a basic data for the future legislation on the quality estimation and safety of medicinal herbs.