• 대한화학회지
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• 제24권3호
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• pp.250-258
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• 1980

여러종류의 자유라디칼들이 이소니트릴에 첨가되어 중간체인 imidoyl 자유라디칼 RN=CR'을 형성한다. 이것은 또한 imine으로부터 imidoyl hydrogen 을 떼어 내는 다음과 같은 반응에 의해서도 생성될 수 있다. RN=C(H)R' ＋ R"${\cdot}{\rightarrow}$ RN=CR' ＋ R"-H 중간체인 imidoyl 자유라디칼은 ${\beta}$-cleavage 및 aton transfer 반응을 통해서 안정된 분자를 형성한다. ${\beta}$-cleavage는 imidoyl 자유라디칼의 구조에 따라서 두개의 다른 방향으로의 반응이 가능하다. Cyanide transfer와 소위 말하는 정상적인 ${\beta}$-cleavage가 그러한 반응들이다. t-Butoxy 자유라디칼이 t-butylisonitrile 7에 첨가되면 중간체인 t-Bu-N=C-O-Bu-t가 생성되는데, 이것은 ${\beta}$-cleavage반응을 통해서 t-butylisocyanate와 t-butyl 자유라디칼을 형성한다. Phenyl 자유라디칼은 7에 첨가되어 중간체인 t-Bu-N=$C-C_6H_5$를 형성하는데 이것은 cyanide transfer 반응을 통해서 benzonitrile과 t-butyl 자유라디칼로 분해된다. 여기서 생성되는 t-butyl 자유라디칼은 다시 7에 첨가하여 intermediate인 자유라디칼 t-Bu-N=C-Bu-t을 형성하고, 이것은 다시 pivalonlonitrile과 t-butyl 자유라디칼로 분해되는데 이러한 반응이 반복되므로 radical chain isomerization을 일으킨다. Silyl 자유라디칼은 7에 첨가되어 t-Bu-N=$C-Si(CH_3)_3$를 형성하고, 이것은 cyanide transfer 반응을 거쳐서 다시 $(CH_3)_3$SiCN과 t-butyl 자유라디칼로 분해된다.

• 한국식품영양과학회지
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• 제34권6호
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• pp.875-879
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• 2005

아마인의 linustatin과 neolinustatin은 가수분해되어 acetone, hydrogen cyanide(HCN) 그리고 sugar를 생성하는 diglucoside 시안배당체로써 가수분해물인 HCN의 독성으로 인해 식품의 안전성에 문제가 되고 있다. $80\%$ methanol 추출과 LC/MSn에 의한 정성분석과 RI-LC에 의한 아마인에서 함유된 시안배당체 함량을 조사한 결과, linustatin과 neolinustatin이 각각 평균 206.5 mg/100 g과 174.2 mg/100 g 함유되어 있었다. 또한 autohydrolysis 후 증류액으로부터 IC 분석 에 의 해 HCN 137.38 mg/kg이 가수분해되어 유리됨을 알 수 있었다. 시안배당체의 저감화를 위하여 가열처리를 수행한 결과, 아마인은 $200^{\circ}C$에서 2시간 이상 가열시 $85\%$ 이상의 linustatin과 neolinustatin 그리고 HCN의 제거효과를 보였다. 특히 $200^{\circ}C$에서 30분 가열시 $98\%$의 HCN이 제거됨을 관찰할 수 있었다.

• 한국연초학회지
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• 제14권1호
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• pp.87-93
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• 1992

The adsorption efficiency of some adsorbents for the organic solvents and gas phase of smoke was investigated. 1. Specific surface area of activated carbon increased to 1900 mfg with increased activation time. 2. Adsorption efficiency of benzene and acetone increased with increasing total surface area. Adsorption capacity for gas phase such as hydrogen cyanide, aldehyde was proportional to the micro pore surface area under 20A. 3. The removal efficiency of particulate matter of smoke was higher with the adsorbents of relatively higher pore size compared to that of micro pore.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.247-250
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• 2001

2, 3-Dicyanopyrazine derivatives have been synthesized by condensation of diaminomaleonitrile(DAMN) and a -diketone compounds. Diaminomaleohitrile (DAMN) is well known as a tetramer of hydrogen cyanide and a useful compound in the chemical industry not on]y as a starting material for synthesis of various heterocyclic compounds but also as an intermediate for synthesis of glycine, adenine, guanine et al. (omitted)

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.104-104
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• 2017

Sorghum (Sorghum bicolor (L.) Moench.) is one of the most important crops for human and animal nutrition. Nonetheless, sorghum has a cyanogenic glucoside compound which can be degraded into hydrogen cyanide, toxic to humans and animals even with tiny amount. In consequence, breeding materials with a low cyanide level has been a top priority in sorghum breeding programs. To fulfill our long-term goal, we are screening sorghum accessions with low cyanide level, which would be an important breeding material for food safety. We collected seeds of various sorghum accessions and analyzed relevant metabolites to find useful breeding materials of sorghum accessions containing low cyanide. Fourteen wild relatives were obtained from the University of Georgia in US, a reference accession BTx623, and three local varieties from National Agrobiodiversity Center of Rural Development Administration in Korea, and one wild species from the Wild Plant Resources Seed Bank of Korea University in Korea. Sorghum plants were grown in plastic greenhouse under natural conditions. After growing, leaf samples were harvested at different developmental stages: seedling phase, vegetative phase (right before flowering), and reproductive phase (ripening). Using collected samples, quantification analysis were performed by an HPLC system for three metabolites (dhurrin, 4-hydroxybenzaldehyde, and 4-hydroxyphenylacetic acid) in sorghum plants. Prior to metabolome analysis, specific experimental condition for HPLC system was set to be able to separate three metabolites simultaneously. Under this condition, these metabolites were quantified in each accession by HPLC system. We observed that the metabolite contents were changed differently by developmental stages and accessions. We clustered these results into five groups as patterns of their contents by developmental stages. Most of accessions showed that 4-hydroxybenzaldehyde content was very high at seedling stage and decreased rapidly at vegetative phase. Interestingly, the patterns of dhurrin content were very different among clusters. However, 4-hydroxyphenylacetic acid content was maintained at low levels by developmental stages in most accessions. The results would demonstrate how dhurrin and alternative degradation pathways are differentiated in each accession.

• 대한화학회지
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• 제7권2호
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• pp.115-121
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• 1963

Aliphatic hydrocarbon gases from rubber pyrolysis have been identified by gas chromatography with tetraethyleneglycol dimethylether column. Rubbers used in this work are polyisoprene, SBR, NBR, polybutadiene, buthyl rubber, polychloroprene and polyurethane rubber. The chromatogram is characteristic for each polymer. Author proposes a method of identification of synthetic rubbers by gas chromatograph of pyrolyzed gas. Sample is pyrolyzed at $450^{\circ}C$ under nitrogen or more effectively helium and gaseous portion, which eliminated liquid condensate, is passed to the column. The appearance of exclusively large peak of isoprene, isobutylene and carbon dioxide shows the presence of polyisoprene, polyisobutylene and polyurethane, respectively. Large peak of butadiene will appear in case of polybutadiene, SBR and NBR, but SBR can be identified through the styrene peak in gas chromatogram of liquid pyrolyzate and NBR can be identified by the evolution of hydrogen cyanide during pyrolysis. Polychloroprene is identified by the evolution of hydrogen chloride. This method could be applied to the identification of copolymer or polymer blend.

• Environmental Engineering Research
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• 제24권4호
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• pp.591-599
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• 2019

To convert sewage sludge to energy, drying-gasification characteristics during microwave heating were studied. During the gasification of carbon dioxide, the main products were gas, followed by char, and tar in terms of the amount. The main components of the producer gas were carbon monoxide and hydrogen including a small amount of methane and light hydrocarbons. They showed a sufficient heating value as a fuel. The generated tar is gravimetric tar, which is total tar. As light tars, benzene (light aromatic tar) was a major light tar. Naphthalene, anthracene, and pyrene (light polycyclic aromatic hydrocarbon tars) were also generated, but in relatively small amounts. Ammonia and hydrogen cyanide (precursor for NO_x) were generated from thermal decomposition of tar containing protein and nitrogen in sewage sludge. In the case of sludge char, its average pore diameter was small, but specific area, pore volume, and adsorption amounts were relatively large, resulting in superior adsorption characteristics.

• 해양환경안전학회지
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• 제7권1호
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• pp.7-14
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• 2001

The amount of petroleum consumption has been Increased according to the industrialization and It leads to the increase of the possibility of marine oil pollution. In Korea, some countermeasures including oil skimmer, gelling agent and herding agent of oil have been used for the remediation of the pollution. However, most of them have lets of shortcomings in the application under in-situ condition, because they are sensitive to the situation such as geographical feature, the wind and the tide. In reported literature, the natural powdered oil absorbent which is made of peat moss is an effective mean to clean spilled oil from lake or coast. However, the peat moss is a natural resource which is only Produced from a specific cold weather are like Canada. This indicates that the alternative materials which is readily obtained from everywhere are needed for powdered oil absorbent. Therefore. in the study, same natural materials including pine leaves and straw are tested as the alternative materials for the absorbent. The raw materials were dried and treated by heat at various temperature during several Periods and then. shattered by a grain cracking machine. The oil sorption capacity of the prepared materials was compared according to the methods of heat treatment and their sizes. The proportion of hydrogen cyanide to combustion of the absorbents was measured to confirm their final disposal methods. The biodegradability test of the absorbents was carried our to evaluate possibility of a side pollution in the coast. In was found that the heat treatment of pine leaves enhanced the capacity of oil sorption and decreased the water sorption. The maximum oil sorption was observed for the material treated at 18$0^{\circ}C$for 60 min. The amount of hydrogen cyanide from the combustion were 0.09ml/g, 0.07ml/g for pine leaves and straw respectively meaning that the final disposal by combustion might be feasible. The amount or organic carbon extracted from pine leaves during 7 days was up to 0.015g organic carbon from one gram of pine leaves. but the degradation was as fast as for glucose. It is concluded that the pine leaves can be served as a good raw material for the powdered oil absorbent like peat moss.

• The Plant Pathology Journal
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• 제34권3호
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• pp.208-217
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• 2018

In this study, samples were collected from the leaves and stems of healthy wild Pistachio trees (Pistacia atlantica L.) from various locations of Baneh and Marivan regions, Iran. In total, 61 endophytic bacteria were isolated and grouped according to phenotypic properties. Ten selected isolates from each group were further identified by partial sequencing of the 16S rRNA gene. Based on the results, isolates were identified as bacteria belonging to Pseudomonas, Stenotrophomonas, Bacillus, Pantoea and Serratia genus. The ability of these isolates was evaluated to phytohormone production such as auxin and gibberellin, siderophore production, phosphate solubilization, atmospheric nitrogen fixation, protease and hydrogen cyanide production. All strains were able to produce the plant growth hormone auxin and gibberellin in different amounts. The majority of strains were able to solubilize phosphate. The results of atmospheric nitrogen fixation ability, protease and siderophore production were varied among strains. Only Ba66 could produce a low amount of hydrogen cyanide. The results of biocontrol assay showed that Pb78 and Sp15 strains had the highest and lowest inhibition effects on bacterial plant pathogens, Pseudomonas syringae pv. syringae Pss20 and Pseudomonas tolaasii Pt18 under in vitro condition. Pb3, Pb24 and Pb71 strains significantly promote root formation on carrot slices. To our knowledge this is the first report of the isolation of endophytic bacterial strains belonging to Pantoea, Bacillus, Pseudomonas, Serratia and Stenotrophomonas genus from wild pistachio trees with plant growth promoting potential and biocontrol activity.

• 한국연초학회지
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• 제27권2호
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• pp.171-177
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• 2005

Coconut based activated carbon and silica-gels were impregnated with 3-aminopropyltri ethoxysilan(APS) and N-(2-aminoethyl)-3-aminopropyl triethoxysilane (AEAPS) in order to investigate the effect of the amine group and the pore size of the supports on the removal of hydrogen cyanide(HCN) and aldehydes in mainstream smoke(MS). The physicochemical properties of the supports were analyzed by using thermal gravity analyzer(TGA), $N_2$ adsorption and desorption isotherms$(BET,\;N_2)$, and SEM-EDS. According to our experimental data, there was no significant difference in the delivery amount of HCN and aldehydes of non-functionalized silica-gels having meso-pores bigger than $20\AA$. In the case of silica-gels functionalized with APS(APS silica-gel), the delivery amounts of hydrogen cyanide(HCN) and aldehydes decreased with the increase of APS concentration. Silica-gel functionalized with AEAPS(AEAPS silica-gel) showed higher removal efficiency than that of APS silica-gels. The delivery amounts of HCN and aldehydes of activated carbon impregnated with APS and AEAPS increased with the increase of the APS and AEAPS concentrations. In accordance with the specific surface area analysis results, APS and AEAPS molecules decreased the specific surface area by blocking the micro-pores of the activated carbon. The volatile organic components removal efficiency by the micro-pores was higher than that of the amine group impregnated into the activated carbon.