• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.741-744
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• 2003

In this study, the influence of chemical admixture on early strength development of concrete is discussed. According to the results, fluidity with variation of kinds of chemical admixture is lower in the case of acceleration type than in the case of normal type. Setting time of naphthalene acceleration type is shortened by I hour, and that of melamine is nearly same, but that of polycarbonic acid is somewhat retarded in comparison with that of naphthalene normal type. Early compressive strength gains 5MPa in about 18hours regardless of the kinds of chemical admixture. But as time elapses, compressive strength is higher in order of polycarbonic acid, naphthalene and melamine type. The relativity between compressive strength and the rebound value of P-type schmidt hammer is also favorable at early age, and compressive strength of 5MPa is estimated at the rebound value of 22.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3829-3834
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• 2013

$H{\beta}$ (core)/SAPO-11 (shell) composite molecular sieve was synthesized by the hydrothermal method in order to combine the advantages of $H{\beta}$ and SAPO-11 for the methylation of naphthalene with methanol. For comparison, the mechanical mixture was prepared through the blending of $H{\beta}$ and SAPO-11. The physicochemical properties of $H{\beta}$, SAPO-11, the composite and the mechanical mixture were characterized by various characterization methods. The characterization results indicated that $H{\beta}$/SAPO-11 composite molecular sieve exhibited a core-shell structure, with the $H{\beta}$ phase as the core and the SAPO-11 phase as the shell. The pore diameter of the composite was between that of $H{\beta}$ and SAPO-11. The composite had fewer acid sites than $H{\beta}$ and mechanical mixture while more acid sites than SAPO-11. The experimental results indicated that the composite exhibited high catalytic performances for the methylation of naphthalene with methanol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.36-37
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• 2004

$\alpha$-Chloromethylnaphthalene is a valuable compound for obtaining of the plant growing stimulator - $\alpha$-napthylacetic acid. Chloromethylation of naphthalene by paraformaldehyde in the presence of glacial acetic acid, phosphoric and hydrochloric acids at temperature 80-85$^{\circ}C$ and duration - 6 hours the $\alpha$-chloromethyl-naphthalene yield was 55-57%. Using Box-Wilson method for mathematical planning of experiment carried out optimization of its synthesis for purpose increasing $\alpha$-chloromethylnaphthalene yield. Preliminary, one - factor experiments were carried out for selecting independence main parameters influencing on the synthesis. A full factor experiment of 2$^3$with extended matrix of planning was used for optimization. Aiming to increase the $\alpha$-chloromethylnaphthalene yield, the obtained mathematical model was used for program of sharp raising on the reply surface. The received optimal conditions for the $\alpha$-chloromethylnaphthalene synthesis were selected as following: molar ratio of naphthalene - parapfsormaldehyde of 1 : 2; temperature -105$^{\circ}C$; duration of the reaction -3 hours. The yield of $\alpha$-chloromethylnaphthalene under these optimal conditions was 75 %.

• Journal of Powder Materials
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• v.25 no.4
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• pp.336-339
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• 2018

A unique porous material with controlled pore characteristics can be fabricated by the freeze-drying process, which uses the slurry of organic material as the sublimable vehicle mixed with powders. The essential feature in this process is that during the solidification of the slurry, the dendrites of the organic material should repel the dispersed particles into the interdendritic region. In the present work, a model experiment is attempted using some transparent organic materials mixed with glass powders, which enable in-situ observation. The organic materials used are camphor-naphthalene mixture (hypo- and hypereutectic composition), salol, camphene, and pivalic acid. Among these materials, the constituent phases in camphor-naphthalene system, i.e. naphthalene plate, camphor dendrite, and camphor-naphthalene eutectic exclusively repel the glass powders. This result suggests that the control of organic material composition in the binary system is useful for producing a porous body with the required pore structure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.147-153
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• 1995

The cultured mycelial cells of Ganoderma lucidum was extracted by alkali, and then neutralized by acid. The extract was passed through the column of DEAE cellulose for more purification. The neutral fraction was concentrated and precipitated with 95% ethanol. The precipitate was lyophilized and then PSG(polysaccharides) was obtained. PSG was composed of 82.2% polysaccharide, 0.7% protein and 17.1% uronic acid. Sugar conjugates of its hydrolysates were produced using with fluorescent compound(7-amino-1,3-naphthalene disulfonic aicd : 7-AGA), and then fluorescent labeled sugar conjugates were separated by reverse phase high perfomance liquid chromatography. Hydrolysates of PSG were composed of sixteen amino acids and 95.7% glucose, 2.7% xylose, 1.6% fucose and tract amount of galactose and mannose. The immunomodulating effects of PSG on macrophage were perfomed using murine macrophage cell line ATCC TIB 71 cells. PSG augumented the phagocytic activity of TIB 71 cells against fluorescent latex beads.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.270-273
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• 1994

Pseudomonas putida 3SK, which was constructed by the conjugal transfet of the $CAM::TOL^{*}$ plasmid of Pseudomonas putida CSnA and the NAH plasmid of Pseudomonas putida KCTC 2403 into n-alkane assimilating Pseudomonas putida KCTC 2405, showed a broad degradation spectrum and floc-forming ability. This strain degraded m-toluic acid, naphthalene, camphor and decane simultaneously. $Hg^{2+}$ at the concentration of 1 ppm in the minimal medium could not inhibit the growth of this strain. The degradation of m-toluic acid by Pseudomonas putida 3SK was not repressed by the easily utilizable compounds, such as glucose and succinate. But, the addition of formalin inhibited the growth of Pseudomonas putida 3SK. After the cultivation of this strain on the artificial wastewater containing m-toluic acid, naphthalene, camphor and decane for 24 hr, the initial COD value (1500) of the artificial wastewater was declined to 300.

• Magazine of the Korea Concrete Institute
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• v.7 no.5
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• pp.189-199
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• 1995

Naphthalene sulfonated condensate has been widely used as a superplasticizer for cement and concrete, but the application was limited due to its large slump loss with elapsed time. To complement this demerit of NSF, polycarboxylic acid copolymer from nlaleic anhydride and acryl~c acid(MA) was synthesized to retain the mobility of cement and concrete, and then mixed with NSF. The physical properties, such as fluidity, fluidityretention and rheology, were measured by applying these admixtures to cement paste as a function of elapsed time. And also compressive strength of mortar was measured with curing time. NIv-l and NM-2 containing 10, 20 wt% of MA respectively had a excellent fluidity and a fluidity- retention. In rheological property, the increases of shear stress and viscosity with elapsed time were delayed with the increasing of shear rate in cornparision with NSF only. The marked slump loss of cement paste could be controlled by these admixture. Also the added ainount of admixture and the ratio of water to cement affected these properties.

• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.85-91
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• 1994

In the previous study, naphthalene and /or naphthol were sulfonated wlth sulfuric acid and they were condensated with formaldehyde. The condensates prepared are subjected to the flow and strength tests of cement rnortnr to examine the chemcal effects of cement adrnlxtures. As the results of flow test, the flow of cement mortar mxed wth naphthol condensates(TSC) and naphthol naphthalene cocondensates( NT5) was larger than those mxed with synthetic naphtha lene condensate (NSS). In the experiments of compressive strength after 28 days curing, the hardned cement mortar containing naphthalene naphthol condensates(N1'5) showed a higher compressive strength than those contairung naphthalene condensates(NSS) and naphthol condensates('I'SC). As a results, the synthetic naphthalene condensates(NT5, TSC 1, whlch used i n this study, are greatly expected as good superplasticizers for the concrete.

• Journal of the Speleological Society of Korea
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• no.71
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• pp.1-4
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• 2006

Chloromethylnaphthalene is a valuable compound for obtaining of the plant growing stimulator - -napthylacetic acid. Chloromethylation of naphthalene by paraformaldehyde in the presence of glacial acetic acid, phosphoric and hydrochloric acids at temperature 80 - 85C and duration - 6 hours the -chloromethylnaphthalene yield was 55-57%. Using Box-Wilson method for mathematical planning of experiment carried out optimization of its synthesis for purpose increasing -chloromethylnaphthalene yield. Preliminary, one - factor experiments were carried out for selecting independence main parameters influencing on the synthesis. A full factor experiment of 23 with extended matrix of planning was used for optimization. Aiming to increase the -chloromethylnaphthalene yield, the obtained mathematical model was used for program of sharp raising on the reply surface. The received optimal conditions for the -chloromethylnaphthalene synthesis were selected as following: molar ratio of naphthalene parapfsormaldehyde of 1 : 2 temperature - 105C duration of the reaction - 3 hours. The yield of -chloromethylnaphthalene under these optimal conditions was 75%.

• Natural Product Sciences
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• v.26 no.4
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• pp.279-282
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• 2020

Chemical investigation of the methanol extract of Koordersiodendron pinnatum Merr. leaves resulted a new naphthalene derivative, (Z)-4-(tetradec-3-enyl)naphthalene-1,2,7-triol (1), together with three known compounds, ��-sitosterol (2), 20-epibryonolic acid (3), and scopoletin (4). The structure of the new compound was elucidated based on spectroscopic evidence. The isolated compounds (1-4) were tested their cytotoxic activities against the P-388 murine leukemia cell line and compound 1 has highest activity with IC50 1.94 μM.