• 한국약용작물학회지
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• 제18권5호
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• pp.345-360
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• 2010

This study was conducted to investigate the content of sulfur dioxide residues in medicinal herbs in Seoul in 2009. Sulfur dioxide in the samples were determined by Monnier-Williams's modified method. A total of 1,821 samples of 205 different types of herbs were collected from Kyung-Dong Herb markets and Oriental medicine hospitals in Seoul. Of these samples, 642 samples were domestic, and 1,179 samples were imported. Of the 1,821 samples, 61 (3.3%, 31 types) failed to meet the regulations for sulfur dioxide residues of KFDA in medicinal herbs. Among these 61 unsuitable samples, 17 (7 types) were domestic, and 44 samples (26 types) were imported. The content of sulfur dioxide in the domestic medicinal herbs ranged from 0 to 809 mg/kg, while those in imported medicinal herbs ranged from 0 to 4,481 mg/kg. Approximately 84.6% of the samples contained less than 10 mg/kg of sulfur dioxide and about 10.0% of samples contained more than 30 mg/kg of sulfur dioxide.

• Journal of the Korean Wood Science and Technology
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• 제15권2호
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• pp.99-104
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• 1987

Fiber mats were made at various density levels, using fibers from papermill sludge, ricestraw and various mixtures of the two. The paper mill sludges were collected from Moorim Papermill Co, and Jeonjoo Papermill Co. They were soaked in the liquid sulfur compounds, sulfur-tall oil and sulfurpolyester compounds, and made into fiber-reinforced, sulfur-based composition board. Under optimum conditions of fiber mat preparation and saturation with molten sulfur and modified sulfur, the Young's moduls of the manufactured tiber-reinforced composition board are superior to those of conventional wood-based composition boards. For example, the moduli of elasticity of the composition board made from papermill sludge, with a density of 0.40gm/$cm^3$, were greater than 1,400,000psi as compared 800,000psi for high density hardboard(1.28gm/$cm^3$). The modulus of rupture of the best reinforced composition board manufactured was over 9000psi, comparable to 6000psi of high density hardboard. The proposed Bryant and Lee's theory, "Modified Rule of Mixtures" can be applicable to the nonoriented and short fibrous composition board, when it was modified from "Rule of Mixtures" established by Paul an Jones, and supplemented by Smith and Cox's theory, In the Bryant and Lee's theory of $E_c=\frac{1}{3}aE_fV_f+bE_mV_m$, the constants "a" and "b" for the composition boards made from papermill sludge and the mixtures of ricestraw and the sludge were identified to be in the ranges of 3.29~3.54 and -2.47~-2.80 respectively.

• Nuclear Engineering and Technology
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• 제52권2호
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• pp.373-380
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• 2020

This study was carried out to convert the hydrophobic characteristics of PVDF to hydrophilic. Poly(-vinylidene fluorine) (PVDF) was grafted by electron beam irradiation and sulfonated. The grafting degree of modified PVDF increased with the monomer concentration, but not the conversion degree. From the results of FTIR and XPS, it was shown that the amount of converted sulfur increased with the grafting degree. The radiation-induced graft polymerization led to decrease fluorine from 35.7% to 21.3%. Meanwhile, the oxygen and sulfur content increased up to 8.1% and 3.2%. The pore size of modified membranes was shrunken and the roughness sharply decreased after irradiation. The ion exchange capacity and contact angle were investigated to show the characteristics of PVDF. The enhanced ion exchange capacity and lower contact angle of modified PVDF showed that the hydrophilicity played a role in determining membrane fouling. Electron beam irradiation successfully modified the hydrophobic characteristics of PVDF to hydrophilic.

• 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.

• Elastomers and Composites
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• 제34권4호
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• pp.299-314
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• 1999

Bonding metal and textile components to rubber has always posed a problem. In this paper, an attempt had been made to modify textile and metal surfaces for bonding with rubber. The metal surfaces were modified using silane coupling agents and textile fibers were modified using plasma polymerization techniques. Some results on adhesion of metals to a range of sulfur-cured rubber compounds using a combination of organofunctional silanes are given here. The treatment was not only effective for high-sulfur compounds but also for low-sulfur com pounds as used in engine mounts and even for some semi-EV compounds. Coatings of plasmapolymerized pyrrole or acetylene were deposited on aramid and polyester tire cords. Standard pull-out force adhesion measurements were used to determine adhesion of tire cords to rubber compounds. The plasma coatings were characterized by various techniques and the performance results are explained in an interpenetrating network model.

• Carbon letters
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• 제27권
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• pp.12-17
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• 2018

We fabricated a Li-S battery with post-treated carbon nanotube (CNT) films which offered better support for sulfur, and investigated the effect of the surface properties and pore structure of the post-treated CNT films on Li-S battery performance. Post-treatments, i.e., acid treatment, unzip process and cetyltrimethylammonium bromide (CTAB) treatment, effectively modified the surface properties and pore structure of the CNT film. The modified pore structure impacted the ability of the CNT films to accommodate the catholyte, resulting in an increase in initial discharge capacity.

• 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.

• 한국식품과학회지
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• 제35권6호
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• pp.1028-1032
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• 2003

절임류에 함유된 이산화황함량의 정확한 분석을 위해 산 증류후 HPLC-UV detector를 이용한 방법과 Monnier-Williams변법으로 실험해보았다. 산증류-HPLC-UV법은 절임류중의 아황산염을 산증류 시킨 후 발생하는 이산화황을 1% triethanolamine용액에 흡수시켜 이를 UV 240nm에서 정량하는 것으로서, 고정상은 음이온 교환컬럼을, 이동상으로는 1.8mM $Na_2Co_3$와 1.7mM $NaHCO_3$용액을 사용하였다. 이 방법으로 단무지에 아황산염을 첨가하여 실험 한 결과 $84.0{\sim}91.7%$의 회수율을 얻었다. 시중에 유통되는 48종의 절임류에 대해 모니어윌리암스변법과 산증류-HPLC-UV법을 이용하여 이산화황 함량을 조사해본 결과, 산증류-HPLC-UV법에 비해 모니어월리암스법에서 휘발성 산으로 인해 높은 농도를 나타내었다. 산증류-HPLC-UV법으로 분석한 절임류의 이산화황 농도는 불검출${\sim}173.05ppm$이었고, 기준인 30ppm을 초과하는 제품은 3건이었다.

• 플랜트 저널
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• 제13권3호
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• pp.36-46
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• 2017

황회수 공정의 연소반응기 안에서는 평형반응 및 kinetic 반응이 동시에 일어난다. 주요 kinetic 반응에 참여하는 성분들은 수소($H_2$), 일산화탄소(CO), 카보닐황화물(COS) 그리고 이황화탄소($CS_2$) 이다. 본 연구에서는 평형반응, 상관관계식(empirical correlations) 그리고 황 회수 공정의 라이센서 자료의 비교를 통해 반응기에서 kinetic components (COS와 $CS_2$)의 생성 양을 분석한다. 또한 kinetic components ($H_2$ 와 CO)의 생성 양의 분석을 통해 반응기에서의 생성 양과 온도와의 상관관계를 분석한다. 부 반응이 전체 연소에 필요로 하는 산소의 양에 어떤 영향을 미치는지도 같이 분석을 한다. 황회수 공정의 반응기내의 부 반응에 대한 충분한 이해는 전체 황회수 공정 설계를 할 때 최적의 장치 설계를 가능하게 하고 나아가 황회수 효율을 극대화 하는데 도움이 된다.

• 한국식품과학회지
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• 제32권3호
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• pp.544-549
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• 2000

본 연구에서는 분석대상식품인 곡류, 과일류, 채소류, 어류둥 20종 180품목의 식품별에 따른 천연 이산화황의 함유량에 대해 모니어월리암스변법, 개량랭킹법 및 산증류/이온배제크로마토크래피법을 각각 적용하여 분석한 후 다음과 같은 결과를 얻었다. 본 연구에서 사웅한 각 실험방법별 회수율은 모니어월리암스변법은 $74{\sim}91%$, 개량랭킹법법은 $67{\sim}87%$, 산증류/이온배제크로마토그래피법은 $68{\sim}88%$의 회수율을 얻을 수 있었으며 모니어월리암스 변법에 의한 조사대상식품의 이산화황 분석결과는 $1.02{\sim}43.87\; ppm$의 범위를 보였고 마늘, 도라지, 파, 양배추 및 양파가 각각 43.87, 15.37, 11.50, 11.21 및 10.60 ppm의 높은 농도로 검출되었으며, 그 나머지 식품은 모두 10.00 ppm 미만으로 낮은 농도를 보였다. 개량랭킹법에 의한 조사대상식품의 이산화황 분석결과는 파와 마늘이 2.87 ppm과 6.41 ppm으로 높게 나타났고 나머지는 대부분 2.00 ppm미만의 낮은 농도를 보였다. 산증류/이온배제크로마토그래피법에 의한 조사대상식품의 이산화황 분석결과는 마늘, 양배추, 파, 양파, 감자 및 사과가 각각 15.43, 9.82, 5.74, 5.37, 2.14 및 0.49 ppm이 검출되었고, 그 나머지는 불검출이었다. 결론적으로, 20종 180품목을 3가지 분석방법을 적용하여 천연으로 존재하는 이산화황의 함유량을 조사한 결과, 여러 식품중 천연으로 존재하는 이산화황의 함유량을 모니터링하는데는 현행 식품공전의 공정시험법인 모니어월리암스변법이 타당한 방법이라고 생각되나, 건조된 파, 양파, 양배추등의 황화합물을 함유하는 식품의 경우에는 모니어월리암스법(AOAC공정법 990.28)에 규정되어 있는 것과 같이 이산화황이외의 황화합물에서 기인되는 휘발성물질이 이산화황으로 같이 검출되므로 건조된 파, 양파, 양배추등의 황화합물을 함유하는 식품의 경우에는 황화합물에서 기인되는 휘발성물질이 이온크로마토그래프에서 배제되고 이산화황만 검출되는 산중류/이온배제크로마토그래피법을 적용하여 분석하는 것이 타당하다고 사료된다.