• Title/Summary/Keyword: methyl bromide

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Study on Fumigation Method of Harvested Fresh Chestnuts Produced in Korea (한국산 생밤의 훈증소독방법에 관한 연구)

  • Hah Jae-Kyu;Lee Cheon-Koo;Yu Ki-Yull
    • Korean journal of applied entomology
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    • v.21 no.3 s.52
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    • pp.133-137
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    • 1982
  • An experiment was conducted to find out the proper and effective fumigation method for harvested fresh chestnuts produced in Korea. Fumigation with phosphine, causing damages on chestnuts by rapid corruption or change in color on pericarp, did not completely kill chestnut curculio and nut fruit tortrix larvae in harvested fresh chestnuts regardless of long exposure of chestnuts to phosphine. Any damages not being appeared by fumigant, fumigation with methyl bromide at $40g/m^3$ for 4 hours at $21^{\circ}C$ would retain the low control against inclusion of any chestnut pests tested. Though fumigation with methyl bromide at $50g/m^3$ for 24hours was effective against any larvae of chestnut insects control, they caused serious damages by making the flesh surface of harvested fresh chests dark or dense brown. However, fumigation with methyl bromide at $50g/m^3$ for 4 hours at $21^{\circ}C$ resulted in complete kill of larvae of Curculio dentipes and Carpocapsa splendana in harvested fresh chestnuts with no significant damages on the treated fruits.

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Effects of Gamma Radiation and Methyl Bromide Fumigation on Physiological and Chemical Quality of Apples (감마선과 Methyl Bromide 처리가 사과의 생리화학적 품질에 미치는 영향)

  • 강호진;정헌식;조덕조;변명우;최성진;최종욱;권중호
    • Food Science and Preservation
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    • v.10 no.3
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    • pp.381-387
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    • 2003
  • ‘Fuji’ apples were treated by gamma irradiation (0 - 3 kGy) or methyl bromide fumigation at commercial conditions (MeBr, 26 g/kg, 4 hr) for quarantine purposes at two different treatment timing after harvest and stored under air at 0$^{\circ}C$ for 4 months. Associated with the treatment timing of irradiation or fumigation, after 40 days of storage at 0$^{\circ}C$ following harvest was more adequate than immediately after harvest in keeping qualities of stored apples. However, more than 2 kGy irradiation and MeBr fumigation were detrimental to physiological and chemical qualities of the fruits. These results show that less than 1 kGy irradiation at the delayed timing has a possibility to be applied as a quarantine procedure without significant changes in the quality of apples.

The Stability Appraisement on Cultural Property Material with the Replacing Fumigation Gas of Methyl Bromide (Methyl Bromide를 대체하는 훈증 가스의 문화재 재질 안정성 평가)

  • Kang, Dai-Ill
    • Journal of Conservation Science
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    • v.25 no.3
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    • pp.283-291
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    • 2009
  • Methyl Bromide that was used as fumigation gas turned out to be the substance of destroying the ozone layer. For that reason, at the Montreal Protocol in 1987 the use of methyl bromide was forbidden starting 2005 in the advanced country. Also according to the 2007 Bali Protocolly methyl bromide is expected to be forbidden and therefore the purpose of this study is to find out the effects of substitution fumigation gas (Ethylene Oxide+HFC 134a, Methyl Iodide, Cyanogen and Argon) on the metal(silver, copper and iron), wood(oregon pine), pigment(yellow, red, blue, white and black), textile(hemp, ramie, jute, silk1 and silk2 / indigo, safflower and cork) and paper. After the fumigation test, ethylene oxide+HFC 134a did not have changes in the weight and color of the material itself before and after the experiment. On exterior alteration, color change occurred partly on paper and metal. Also, in most materials color change extent was 0.5 to 1.5 on the average and showed scanty difference. The materials after the fumigation test with methyl iodide did not show weight changes after the test. However, color changes more than 1.0 was shown in most of the materials especially in dyed textile material. In blue pigment, the discoloration on the surface could be seen by naked eyes. Fumigation test with cyanogen gas did not show weight changes and discoloration is more than 1.5 before and after the test. The weight changes of test materials with the argon gas was decreased about 3 to 6%. It can be observed that discoloration on paper was generated. Color changes can be seen on jute dyed with safflower and cork for two weeks with argon gas and the extent was 6.3 and 6.0.

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Exposure Assessment of Biological Monitoring by Urinary Bromide Ion in Methyl Bromide Fumigation Workers (메틸브로마이드 훈증제 작업자의 요 중 브로마이드 이온을 이용한 생물학적 노출평가)

  • Seo, Jeong-Wook;Kim, Byoung-Gwon;Kim, Yu-mi;Lee, Se-Young;Kim, Na-Young;Lim, Hyoun-Ju;Gu, Dongchul;Hong, Young-Seoub
    • Journal of Environmental Health Sciences
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    • v.45 no.6
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    • pp.675-687
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    • 2019
  • Objective: Methyl bromide (MB) fumigant has been shown to be fatal to human when was exposed. However, it were still used the significant amount in quarantine disinfection sites. The purposes of this study were to assess the MB exposure status and characteristics by fumigation-related workers and to provide supporting data for management plan. Methods: For this study, the three groups related to fumigation work were composed. A total of 107 workers were directly exposed, 20 field inspectors were indirect, and 20 general quarantines were not exposed. The urinary bromide ion concentrations in each group were analyzed by using HPLC/ICP-MS, and the working characteristics were identified using the structured questionnaire. Results: The urinary bromide ion concentration in the exposed group of fumigation workers was higher than the indirect and non-exposed groups. In the work characteristics of workers, there was a significant tendency to increase urinary bromide ion concentrations with higher fumigation work years (≤4 years: 2.84 (1.13-7.11) mg/g cr, >4-15 years: 5.36 (4.37-6.57) mg/g cr, >15-37 years: 6.69 (5.27-8.49) mg/g cr, p=0.034). In the comparison of the average number of working days per month, the more working days, the higher the urinary bromide ion concentration was statistically significant (≤12.5 days: 2.59 (1.19-5.65) mg/g cr, >12.5-19.25 days: 5.46 (4.62-6.44) mg/g cr, >19.25-27.25 days: 7.93 (5.93-10.59) mg/g cr, p=0.002). Conclusion: This study was the first nationwide survey including biological monitoring in workers exposed to methyl bromide. The results of this study were expected to be used as a reference for workers' health rights in relation to fumigation, prevention of addiction accidents, and safe management plan.

Kinetic Studies on Halogen Exchange of 1-Naphthyl Methyl Halides (1-나프틸메틸 할라이드의 할로겐 교환반응)

  • Lee Kae-Soo
    • Journal of the Korean Chemical Society
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    • v.13 no.2
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    • pp.115-120
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    • 1969
  • Kinetics of reactions of halide ions with 1-naphthyl methyl halide have been investigated in anhydrous acetone. Semi-quantitative analysis of the results shows that if the softness of the substrate increases remarkably, the nucleophilicity order of halide ions is $I^- > Br^- > Cl^-$ even in dipolar aprotic solvent. But for 1-naphthyl methyl bromide, though the reaction center which was made soft by symbiosis of bromine atom raises the reactivity of soft nucleophile, nucleophilicity order indicates that soft-soft interaction is interfered by perihydrogen.

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Synthesis of 2'-Methyl and 4'-Hydroxy Branched Novel Carbocyclic Nucleosides (2'-메칠 및 4'-하이드록시 측쇄를 가진 새로운 카보사이클릭 뉴크레오사이드의 합성)

  • 홍준희;고옥현
    • YAKHAK HOEJI
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    • v.47 no.6
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    • pp.417-421
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    • 2003
  • This paper describes a synthetic route to novel 2'-methyl and 4'-hydroxy carbocyclic nucleosides. The methyl group was successfully installed by carbonyl addition reaction of isopropenyl magnesium bromide followed by ring-closing metathesis and the hydroxy group was directly introduced from carbohydrate chiral template "D-lactose".ose".uot;.

Aroma Analysis by the Electronic Nose on Red Ginseng Powder Treated with Gamma Radiation, Methyl Bromide and Phosphine (전자코를 이용한 감마선, methyl bromide 및 phosphine 처리된 홍삼분말의 저장 중 향기패턴 변화 연구)

  • Shin, Jung-Ah;Kwon, Joong-Ho;Lee, Ki-Teak
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.825-829
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    • 2003
  • An electronic nose was applied to analyze the aroma patterns of powdered red ginseng that had been treated with different preservative methods, such as gamma radiation at 5kGy, commercial methyl bromide (MeBr) and phosphine fumigations. Aroma patterns of phosphine or MeBr, fumigated samples were well separated according to storage temperature and period. However, 5kGy-irradiated samples (stored for 1 and 2 months) were hardly discriminated by the different storage temperatures ($25^{\circ}C$ and $-10^{\circ}C$). After 5 months at $-10^{\circ}C$, non-treated and phosphine fumigated samples showed similar aroma patterns.

The Interaction of Gallium Bromide with Ethyl Bromide in Nitrobenzene and in 1,2,4-Trichlorobenzene (니트로벤젠溶液 및 1,2,4-트리클로로벤젠 溶液內에서의 브롬化갤륨과 브롬化에칠과의 相互作用)

  • Sang Up Choi
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.65-68
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    • 1963
  • The solubility of ethyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene has been measured at $19^{\circ}$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of ethyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating the stronger interaction of ethyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. When there exists gallium bromide in the system, an unstable 1: 1 complex, C2H5Br·GaBr3, of gallium bromide with ethyl bromide is formed in the solution. The 1: 1 complex in solution dissociates into the components to a large extent according to one of the following equilibria or both: $C_2H_5Br{\cdot}GaBr_3{\rightleftarrows}C_2H_5Br+GaBr_3$C_2H_5Br{\cdot}GaBr_3{\rightleftarrows}C_2H_5Br+1}2GaBr_3$$ The stability of the 1: 1 complex of ethyl bromide with gallium bromide is compared with that of the corresponding complex of methyl bromide.

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Effects of Gamma Irradiation and Methyl Bromide Fumigation on the Qualities of Fresh Chestnuts during Storage

  • Kwon, Joong-Ho
    • Food Science and Biotechnology
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    • v.14 no.2
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    • pp.181-184
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    • 2005
  • Effects of irradiation and fumigation on disinfestation and quality attributes of chestnuts during storage were studied. Fresh chestnuts were exposed to gamma irradiation (0-10 kGy) and methyl bromide (MeBr) under commercial conditions and stored at different temperatures for 6 months. Pest of quarantine importance for chestnuts, Curculio sikkimensis Heller showed 100% mortality by MeBr on 3rd day after fumigation and by irradiation at 0.5 kGy in about 3 weeks at $23{\pm}0.5^{\circ}C$. Respiration rates of samples one day after treatments increased in proportion to irradiation dose. Respiration pattern of MeBr group was equal to that of 10 kGy-group. Both MeBr and irradiation at 0.25 kGy or higher showed 100% inhibition of sprouting during storage at $5^{\circ}C$ for 6 months. Flesh firmness was significantly reduced by MeBr or irradiation over 5 kGy (p<0.05) 1 day after treatments. MeBr fumigation resulted in appreciable decrease in flesh weight, reducing sugar and ascorbic acid contents (p<0.05), as compared to irradiated samples. Irradiation at 0.5 kGy was effective as alternative to MeBr in controlling pests while maintaining overall quality of fresh chestnuts during storage.