• Bulletin of the Korean Chemical Society
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• v.16 no.4
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• pp.349-355
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• 1995

Bromo-and chlorotrimethylsilane react with selenium dioxide in halocarbon solvents and generate selenium oxybromide and oxychloride, respectively. These in-situ generated oxyhalides turned out to be very efficient for selective bromination and chlorination of aldehydes and ketones. Under carefully controlled reaction conditions, second and third introduction of halogens into carbonyl compounds can be greatly suppressed, and high yields of monohalo compounds were obtained. The product ratios of this halogenation reactions can be best explained if the reactions are assumed to involve intermediate β-ketoselenenyl chlorides.

• Resources Recycling
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• v.27 no.1
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• pp.38-44
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• 2018

A large amount of Nd-Fe-B magnet scraps are generated during magnet manufacture process. In this study, selective chlorination of the rare earth elements by hydrogen chloride gas which obtained from the pyrolysis of polyvinyl chloride (PVC) was investigated. In thermogravimetric analysis, drastic weight loss was occurred at about 500 K and 710 K. At the isothermal experiments, the weight loss reaches about 30% above 673 K. XRD patterns characterized that after each experiments, ${\alpha}$-Fe, Nd oxychloride, Nd chloride, and Fe chlorides were formed, and the leaching residues remain only ${\alpha}$-Fe. The yields of Nd, Dy, and Fe for the isothermal experiment were increased with temperature and peaked at 873 K. As PVC ratio increased, the yields of Nd, Dy and Fe were also increased.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.8-13
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• 2012

The experiments have been performed to obtain zinc complex compound with smaller particle size, which is used as a charge control agent in manufacturing toner. Metallic salts and polyhydric alcohols have been studied to investigate their effects on the formation of different sizes of zinc complex-compound particle. Reactants such as zinc chloride and 3,5-di-tert-butyl salicylic acid have been used to form the complex compound. Polyethylene glycol (PEG-300), glycerin and ethylene glycol have been added into the zinc chloride solution beforehand to lower the reaction rate in the formation of zinc complex-compound. Zirconium (IV) oxychloride octahydrate has been mixed in the zinc chloride solution beforehand to restrain crystals from growing. When PEG-300 and zirconium (IV) oxychloride octahydrate are used to lower the reaction rate and to restrain the particle size from growing, the average particle size of zinc complex compound decreases from 5.28 to 1.84 ${\mu}m$, which is 34.9% of 5.28 ${\mu}m$.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.719-728
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• 2005

A novel 2-amino-4-(8-quinolinol-5-yl)-1- (p-tolyl)-pyrrole-3-cabonitrile (2) was obtained by the reaction of 2-[2-bromo-1-(8-hydroxyquinolin-5-yl)-ethylidene]-malononitrile (1) with p-toluidene. The new synthon compound (2) could be annelated to the corresponding pyrrolo[2,3-d]pyrimidines (4, 6, 7, 26-28), triazolo[1,5-c]pyrrolo[3,2-e]pyrimidines (10, 29, 30), pyrrolo[2,3-c]pyrazoles (11-15), pyrrolo[1,2-a]pyrrolo[3,2-e] pyrimidine (17) and imidazo[1,2-c]pyrrolo[3,2-e]pyrimidines (18-25) via the reaction with some reagents such as acetic anhydride, formamide, triethyl orthoformate, hydrazine hydrate, hydroxylamine, ethylenediamine, carbon disulfide and phosphorus oxychloride. Chemical and spectroscopic evidences for the structures of these compounds are presented. The antifungal and antibacterial activity of the newly synthesized comounds were evaluated.

• Korean Journal of Agricultural Science
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• v.26 no.1
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• pp.1-5
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• 1999

This experiment was carried out to define the development of control method against rhizome rot of ginger. It was difficult to control of rhizome rot of ginger completely by way of only rhizome sterlization. When soil were stenilized with dazomet, and metalacxyl granule was applied, higher than 95% of control value as well as 39% of yield increase compared to control were found. Soil drenching with metalacxyl cupper oxychloride and streptomycin controlled the rhizome rot satisfactorily, but was inferior to the above mentioned combination.

• Textile Coloration and Finishing
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• v.2 no.4
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• pp.251-256
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• 1990

Bis-(p-bromopheny)phosphate(BBPP) , which serves as flame retardant for PET fabric, was synthesized from phenol and phosphorus oxychloride, and from bromine. In order to investigate the flame retardancy of BBPP, PET fabrics were steam-cured with diluted BBPP solution. The following conclusions were drawn : 1. Flame retardancy of PET fabrics treated with BBPP was excellent, and optimal treating condition was 10% concentration of flame retardant at $170^{\circ]C$ 2. Clark softness and tensile strength before and after the laundering of PET fabrics treated with flame retardant remained nearly unchanged.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.78-81
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• 1990

N-Aryl-N'(4-hydroxy-6-methyl-2-pyrimidinyl)guanidines (IIa-c) were prepared by cyclization of N-arybiguanides (Ia-c) with ethyl acetoacetate. Coupling of compounds (IIa-c) with the appropriate diazotized arylamine gave N-aryl-N'-(5-arylhydrazono-6-methyl-4-oxopyrimidin-2-yl) guanidines (IIIa-f). Whereas, their chlorination with phosphorus oxychloride followed by treatment of N-aryl-N'-(4-Chloro-6-methyl-2-pyrimidinyl)guanidimes (IVac) with the appropriate arylamine afforded the corresponding 4-arylamino derivatives (Vaf). Compounds (IIa-f) were also formed when compounds (1a-c) were treated with ethyl 2-arylhydrazono-3-oxobutyrates. The antimircobial testing of some of the prepared compounds against some pathogenic microorganisms revealed that only two have a marked effect against Escherichia coli.

• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.331-335
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• 1996

1993년 전북완주와 충남 서산 지역에서 생강 근경 부패병에 감염된 식물체로부터 Pythium sp.를 분리하였으며, 52균주를 형태적 특징과 병원성 검정을 통해 Pythium zingiberum으로 동정하였다. P. zingiberum으로 동정된 균주들이 재배지에서 사용되는 metalaxyl(MT), metalaxyl+copper oxychloride(MC), echlomezol(EM) 및 propamocarb hydrochloride(PC)등에 균사 생장, 난포자 형성에 미치는 영향 및 약제방제 효과 등을 검토하였다. MT, MC, EM 등이 혼합된 평판배지에서의 균사생육 정도는 50, 100 mg/L에서도 균사생장 억제를 나타냈으나 3균주는 EM 100mg/L에서도 균사생장이 저지되지 않았다. 100mg/L에서도 균사생육 억제효과가 적은 PC의 경우 저항성균주의 난포자 형성량은 약제 희석농도가 높아질수록 저하되었으나, 감수성을 나타낸 균주는 10, 50mg/L에서 오히려 증가하였다. 또한 폿트실험을 통한 약효검정 결과에서도 MT, MC, EM등은 대조구에 비해 생강 근경부패병을 억제하였다.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.165-167
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• 2002

Date palm (Phoenix dactylifera) is an important fruit and cash crop in Sultanate of Oman, occupying nearly 60% of the total cultivated area. However, leaf spots caused by Mycosphaerella tassiana, Alternaria spp., and Dreshcleri sp. have become a threat to date palm's cultivation in recent years. In this study, a field experiment was conducted to find out a suitable chemical spray program to control the disease. A prophylactic spray schedule with mancozeb (Dithane M45), copper oxychloride (Champion), and mancozeb+copper (Trimiltox) effectively controlled the disease when applied at a time when the disease severity index (DSI) was low, ranging from 0 to 1.68. Meanwhile, the disease did not decrease, but instead increased gradually, when the fungicide combination was applied when DSI was high, ranging from 1.78 to 5.37. It was concluded that fungicides should be applied at the early stage or before disease initiation in order to control the disease effectively.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.2
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• pp.137-139
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• 1988

A total synthesis of solanone was investigated. 4-Cyano -2-isopropylbutanal was treated with methallyl iodide in the presence of metallit tin, alominium and HBr to obtain 7-cyano-5-isopropyl-4-hydroxy-2-methyl-1-heptene, which was contacted with phosphorus oxychloride, followed by methylation of dienonitrile, yielded the solanone.