• Korean Journal of Materials Research
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• v.30 no.10
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• pp.515-521
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• 2020

Organic-inorganic hybrid perovskite nanocrystals have attracted a lot of attention owing to their excellent optical properties such as high absorption coefficient, high diffusion length, and photoluminescence quantum yield in optoelectronic applications. Despite the many advantages of optoelectronic materials, understanding on how these materials interact with their environments is still lacking. In this study, the fluorescence properties of methylammonium lead bromide (CH₃NH₃PbBr₃, MAPbBr₃) nanoparticles are investigated for the detection of volatile organic compounds (VOCs) and aliphatic amines (monoethylamine, diethylamine, and trimethylamine). In particular, colloidal MAPbBr₃ nanoparticles demonstrate a high selectivity in response to diethylamine, in which a significant photoluminescence (PL) quenching (~ 100 %) is observed at a concentration of 100 ppm. This selectivity to the aliphatic amines may originate from the relative size of the amine molecules that must be accommodated in the perovskite crystals structure with a narrow range of tolerance factor. Sensitive PL response of MAPbBr₃ nanocrystals suggests a simple and effective strategy for colorimetric and fluorescence sensing of aliphatic amines in organic solution phase.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.105-112
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• 1997

The smelly nitro compounds were extracted from dried fishes by simultanous distillation and extraction, then were analyzed by GC-MS. Carbon number and order of an amine could be predicted by using retention time and equivalent chain length. Anchovy, codfish, imitation crab meat, cuttle fish, file fish, pollack, shrimp, octopus, harvest fish, and hard-shelled mussel were used for this investigation. Various smelly nitro compounds such as methylamine, acetamide, thiazole, 2-hydroxy isopropylamine, N-methyl pyrroline, piperidine, cyclohexylamine were identified, however, dimethylamine, trimethylamine, diethylamine were not detected. Principal components analysis was applied to GC-MS profiles for pattern recognition of smelly nitro compounds in dried fishes. Multivariate aspects using principal components analysis were very useful for pattern recognition of smelly components, category similarity.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.6-11
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• 1999

Dialkylamine (di-)nitrobenzoates as vapor corrosion inhibitor were synthesized with dialkylamines and (di-)nitrobenzoic acids. The compounds were analyzed by elemental analyzer, FT-IR and $^1H$-NMR spectrophotometer. Corrosion inhibition of synthetic compounds and additives [$(NH_4)_2CO_3$, $NaHCO_3$] against ferrous and non-ferrous metal was investigated by potentiostatic method [1% (w/v) corrosion inhibitor in 1M $Na_2SO_4$ aqueous solution] respectively. For corrosion inhibition of ferrous metal, dialkylamine 4-nitrobenzoates were better inhibitor than dialkylamine 3, 5-dinitrobenzoates, the passivating current density ($i_p$) of dialkylamine 4-nitrobenzoate was shown $4.78mA/cm^2$. While, for non-ferrous metal, dialkylamine 3, 5-dinitrobenzoates were better, those of dipropylamine 3, 5-dinitrobenzoate and hexamethyleneimine 3, 5-dinitrobenzoate were shown 36 and $37mA/cm^2$. Additive effect of $(NH_4)_2CO_3$ and $NaHCO_3$ for corrosion inhibition of ferrous metal was excellent but that of non-ferrous metal was not. Optimum ratios of diethylamine 4-nitrobenzoate with $(NH_4)_2CO_3$ and $NaHCO_3$ were 4 : 6 and 5 : 5 (V/V), and passivating current densities ($i_p$) of the mixtures were shown 0.26 and $0.85mA/cm^2$, respectively.

• YAKHAK HOEJI
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• v.30 no.4
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• pp.163-168
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• 1986

Thirteen compounds were synthesized by condensing the N-heterocyclic amines (piperidine, pyrrolidine, morpholine) and secondary aliphatic amines (dimethylamine, diethylamine) with 3,4-methylenedioxyphenylalkenoic acid chlorides for developing CNS depressants. Among them, N, N-diethyl-3,4-methylenedioxycinnamamide (IX) and N, N-dimethyl-5-(3,4-methylenedioxyphenyl)-2, 4-pentadienoic acid amicle (XII) exhibited strong activity in antagonism against pentylenetetrazole-induced convulsion, strychnine-induced convulsion and maximal electroshock seizure. N, N-Dimethyl-3, 4-methylenedioxycinnamide (VIII) showed more potent activity in antagonism against strychnine-induced convulsion and maximal electroshock seizure and in the prolongation of hexobarbital sleeping time.

• Archives of Pharmacal Research
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• v.25 no.1
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• pp.28-38
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• 2002

A series of Schiff's benzimidazole bases, thiosemicarbazides were synthesized, azole ring systems as 1,3,4-triazole, 1,3,4-oxadiazole were prepared. 1-Methylbenzimidazole incorporated to substituted dithio-carbamate, thiophenol, diethylamine via acetamido group were synthesized. A series of pyrimidinobenzimidazoles, triazinobenz-imidazoles, and 2-(acetonylamino)-1-methyl-benzimidazole were prepared. The antimicrobial and molluscicidal activities of some newly prepared compounds were carried out.

• Resources Recycling
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• v.20 no.6
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• pp.78-82
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• 2011

Supercritical $CO_2$($scCO_2$) extraction has a great possibility to be a new process to recover metal and to replace the existing leaching/solvent extraction processes. The cobalt extraction was carried out using $scCO_2$ from cobalt sulphate solution. The bis (2,4,4-trimethylpentyl) phosphinic acid and diethylamine ligands were used to extract cobalt ion in $scCO_2$. The recommended method consists of $scCO_2$/extractants complexation process and metal extraction process at 60, 200bar. Experimental results showed that the extraction efficiency of Co was increased by 16-99% with increasing the ligand amount.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.115-120
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• 1974

Secondary amines are known as one of the precursors of nitrosamines which are potent carcinogenic compounds of man and animals. Nitrosamines are formed when both secondary amines and nitrite are present. The nitrites are occurred naturally in vegetables, fruits and many others, and frequently used in fish product as a color fixative or a preservative. In this paper, to know the formation of nitrosamines in fish meat, the changes of dimethylamine (DMA) content during the heat treatment such as drying, roasting and fish cake processing are discussed. The results showed that generally DMA increased considerably during heat processing. During drying, DMA in cuttle fish increased 16 times higher, while in Alaska pollack doubled than the fresh. In the roasted mackerel, the DMA content appeared 6 times higher than the fresh, while 9 times higher in canning. In fish cake from yellow corvenia, DMA increased 4 times higher than the fresh. On the contrary diethylamine and diphenylamine were not found in this experiment.

• Textile Coloration and Finishing
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• v.6 no.4
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• pp.46-53
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• 1994

Polymer cationic agent was prepared by the initial polymerisation of epichlorohydrin followed by amination with diethylamine. Cotton fibre treated with the polymer (6~8% o.w.f.) is highly cationic and exhibit increased substantivity for reactive dyes under neutral to weakly acid conditions. The modified substrate could be dyed with reactive dyes without salt or a little salt from dye bath. The increased concentration of cationic agents resulted in an increase the colour yield. Futhermore, treated cotton has an electropositive surface charge. Adsorption of Reactive dye can be attributed to both van der waals force and electrostatic attraction.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.230-230
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• 2003

Chalcopyrite 구조를 가진 CuInSe$_2$ (CIS) 나노입자를 유기용매인 diethylamine을 사용하여 autoclave안에서 용매열법(solvothermal method)으로 제조하였다. 180 $^{\circ}C$에서 36시간 반응시켜 길이가 10-30 nm, 폭이 5-10 nm인 rod-Eke 형상을 한 CIS 나노입자를 얻었다. 반응온도를 25$0^{\circ}C$로 증가시키고 동일한 반응시간에서 보다 미세하고 균일한 구형의 CIS 나노입자를 관찰할 수 있었다. 한편, 190 $^{\circ}C$에서 얻어진 CIS 나노입자는 36시간을 반응시킨 경우 구형으로 관찰되었으나 60시간 반응시킨 경우는 길이가 50-100 nm 인 rod-like 입자로 성장하였다. 이와 같이 반응시간과 온도를 달리하여 나노입자의 형상이 바뀌는 것을 입자성장기구의 관점에서 고찰하였다. 반응시간과 온도에 따라 얻어진 CIS 나노 입자들의 결정성, 미세구조 그리고 정량 및 정성분석을 XRD, SEM, TEM, EDS등으로 각각 행하였다.

• Journal of Nutrition and Health
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• v.11 no.1
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• pp.17-20
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• 1978

The materials carcinogenic agent, nitrosoamine, is distributed in food circumstances, and is formed when both nitrite and secondary amine are present. Nitrites are added to fishes as a color fixative or preservative and secondary amines exist in fishes. In order to find the distribution and contents of secondary amines, analysis of 19 kinds of fish was conducted. The results showed that, significant differences were not observed in the quantity of secondary amines in 19 kinds of fish by district. The highest value was 20.29 ppm in Theragra chalocogramma and the lowest was 0.022 ppm in Ostrea denselamellosa. Six fishes below 1 ppm were Nibea imbricata, Misgurnus mizolepis, Astroconger myriaster, Evynnis Japonica, Ostrea denselamellosa and Solen gouldi. Dimethyl amine only was identified and diethylamine or diphenylamine was not detected in all kinds of 19 fishes.