• Macromolecular Research
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• v.10 no.3
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• pp.168-173
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• 2002

Unstabilized low-density polyethylene (LDPE) films and films formulated with hindered amine light stabilizer (HALS) were exposed to UV-radiation; and the physicochemical changes during photooxidation processes have been investigated using tensile, FTIR spectre-photometric and thermal analytical (DSC) techniques. The dependence of tensile properties (elongation- and stress-at-break), carboxyl index and heat of fusion on UV-irradiation time have been discussed. The use of HALS is found to be effective in maintaining the UV-mechanical properties of the LDPE films. The experimental results showed that there exists no correlation between mechanical properties and carbonyl index, whereas crystallinity correlates well with carbonyl index in unstabilized and stabilized films for irradiation times greater than 100 h. The rate of formation of carbonyl groups is found to be dependent on UV exposure time. Crystallinity of the film samples is strongly influenced by both exposure time and presence of HALS.

• Nuclear Engineering and Technology
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• v.4 no.1
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• pp.35-38
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• 1972

A study of the radiation-induced formation of carbonyl compounds in solid starch by means of precipitation with 2, 4-dinitrophenylhydrazine and subsequent analysis of the hydrazones by gas chromatograph has been performed. formation of carbonyl groups was found to increase linearly with increasing doses up to about 2$\times$10$^{21}$ eV/g. Generally, at least 5 different peaks can be detected including formaldehyde and acetaldehyde.

• Journal of the Korean Chemical Society
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• v.62 no.4
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• pp.265-268
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• 2018

The solvolyses of anthraquinone-2-carbonyl chloride (1) were studied kinetically in 27 pure and various mixed solvents. The analysis using the extended Grunwald-Winstein equation in the solvolyses of anthraquinone-2-carbonyl chloride (1) obtained the l value of $2.11{\pm}0.11$, the m value of $0.54{\pm}0.06$, and the correlation coefficient of 0.955. The solvolysis reaction of 1 might proceed via an associative $S_N2$ mechanism enhancing bond making than bond breaking in the transition state (TS). This interpretation is further supported by a relatively large solvent kinetic isotope effect (SKIE, 2.27).

• Nutritional Sciences
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• v.3 no.1
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• pp.18-24
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• 2000

Peroxidative stimuli mediated by high polyunsaturated fatty acid administration in rats induced in vivo lipid peroxidation and resulted in increased urinary excretion of a number of lipophilic aldehydes and related carbonyl compounds. These secondary lipid peroxiation products, measured as 2, 4-dinitrophenylhydrazine deritives, were detected and identified by the newly developed HPLC method. The identified urinary lipophilic nonpolar aldehydes and related carbonyl compounds were butanal, butan-2-one, pentan-2-one, hexanal, hex-2-enal, hepta-2, 4-dienal, hept-2-enal, octanal, and oct-2-enal. Lipophilic polar aldehydes such as 4-hydroxyhex-2-enal and 4-hydroxyoct-2-enal were also identified. A polyunsaturated fatty acid diet containing n-3 fatty acids generally caused high levels of urinary excretion of lipophilic aldehydes and related carbonyl compounds in rats than a normal diet. Significantly increased secondary lipid peroxidation products were hexanal, hepta-2, 4-dienal, octanal, 4-hydroxyhex-2-exal, 4-hydroxyoct-2-enal, and a number of unidentified compunds.

• YAKHAK HOEJI
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• v.39 no.5
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• pp.516-520
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• 1995

The anti-dansyl antibodies were specifically labeled with stable isotope by growing hybridoma cells in serum-free medium. Assignments of the observed carbonyl carbon resonances have been determined by using $^{13}C-{15}N$ double labeling method in order to assign the Leu resonances. However, when the identical dipeptide appears more than twice in the polypeptide sequences, we applied the proteolytic fragments in the fragment-specific method. Carboxypep-tidase B-treated antibody has also been used to assign the Lys-447 in C terminal amino acid. These unambiguously assigned carbonyl carbon resonances in antibodies are thought to be useful in elucidating not only the structure of antibodies but also the structure-function relationship in the antibody by $^{13}C$ neuclear magnetic resonance spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1380-1384
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• 2001

The chemoselective reactions of 1,n-dicarbonyl compounds with allyl halides using indium metal were investigated. $\alpha-Ketoesters$ such as ethyl pyruvate, ethyl 3-methyl-2-oxobutyrate and ethyl benzoylformate reacted with a variety of allyl halides i n the presence of indium to afford hydroxy unsaturated carbonyl compounds in good to excellent yields in MeOH/HCl at $25^{\circ}C.$ For the allyl bromide, the presence of various substituents at the $\alpha$ or $\gamma$ position exhibited little effects on both the reaction rates and yields. Ethyl acetoacetate or ethyl levulinate was treated with allylindium reagent to give hydroxy unsaturated carbonyl compounds in good yield. These results mean that both reactivity and selectivity are independent of the distance between carbonyl groups. 2,3-Butanedione or 1-phenyl-1,2-propanedione reacted with allylindium to produce monoallylation product as major compound.

• Analytical Science and Technology
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• v.35 no.4
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• pp.143-152
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• 2022

In this review, previous studies on the synthesis and characterization of the metal Complexes with paracetamol by elemental analysis, thermal analysis, (IR, NMR and UV-Vis (spectroscopy and conductivity. In reviewing these studies, the authors found that paracetamol can be coordinated through the pair of electrons on the hydroxyl O-atom, carbonyl O-atom, and N-atom of the amide group. If the paracetamol was a monodentate ligand, it will be coordinated by one of the following atoms O-hydroxyl, O-carbonyl or N-amide. But if the paracetamol was bidentate, it is coordinated by atoms (O-carbonyl and N-amide), (O-hydroxyl and N-amide) or (O-carbonyl and O-hydroxyl). The authors also found that free paracetamol and its complexes have antimicrobial activity.

• Bulletin of the Korean Chemical Society
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• v.27 no.7
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• pp.1079-1082
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• 2006

• Bulletin of the Korean Chemical Society
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• v.23 no.11
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• pp.1503-1504
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• 2002

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.587-588
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• 2006