• Archives of Pharmacal Research
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• v.10 no.2
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• pp.132-141
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• 1987

New triterpenoid saponins, ilexosides A, D, E, J, K and O have been isolated form the root of Ilex pubescens. Chemical and spectroscopic studies have established their structures as shown in formulae 1, 2, 8, 11, 3, 4 and 5.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.206-211
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• 1987

The photoreaction of 5,7-dimethoxycoumarin with adenosine has been carried out in a dry film state. The mixture of DMC and adenosine was irradiated with 350 nm UV light and two major products were isolated. The structure was determined by various spectroscopic measurements involving $^{13}C$ nuclear magnetic resonance and fast atom bombardment mass spectrometry. These addition products were produced by covalent bond formation between the pyrone ring at carbon 3 or 4 and the sugar ring moiety of adenosine at carbon 5'.

• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.334-338
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• 1996

Tetra-chlorodibenzo-p-dioxins (tetra-CDDs) were prepared by microscale pyrolysis of trichlorophenates. During the pyrolysis reaction, tri-, di-, and mono-CDDs were also formed by the thermolysis of tetra-CDDs. The dechlorination pathways of tetra-CDDs were suggested for this reaction. The identification of these products was performed with capillary column gas chromatography-mass spectrometry.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.93-99
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• 2004

At present, LG Electronics pushes ahead to eliminate the Pb(Lead) -a hazardous material- from all products. Especially, we have performed to select the optimum standard composition of lead free alloy for the application to products for about 3 years from 2000. These days, we have the chance for applying to the mass-production. This project constructed the system for applying the lead free solders on consumer electronic products, which is one of the major products of the LG Electronics. To select the lead free solders with corresponding to the product features, we have passed through the test and applied with Sn-3.0Ag-0.5Cu alloy system to our products, and for the application to the high melting temperature composition, we secured the thermal resistance of the many parts and substrate and optimized the processing conditions. We have operated the temperature cycling test and the high temperature storage test under the standards to confirm the reliability of the products. On these samples, we considered the consequence of our decision by the operating test. For the long life time of the product, we have operated the temperature cycling test at $-45^{\circ}C-+125^{\circ}C$, 1 cycle/hour, 1000 cycles. Also we have tested the tin whisker growth about lead free plating on lead finish. We have analyzed with the SEM, EDS and any other equipment for confirming the failure mode at the joint and the tin whisker growth on lead free finish.

• Bulletin of the Korean Chemical Society
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• v.24 no.9
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• pp.1276-1280
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• 2003

Thermal behavior of bromphenols was investigated by direct pyrolysis at high temperature. The thermal degradation products formed by the pyrolysis of mono-bromophenols (o-, m-, and p-) were identified by gas chromatography-mass spectrometry. During the pyrolysis reactions, several kinds of dioxins and furans were produced, and the relative ratio of pyro-products was dependent on the substituted position of bromine in phenolic structure due to the effect of symmetry and steric hindrance. The formation of dioxins can be explained by the phenoxy radical addition and Br atom elimination at an ortho-carbon site on phenolic structure. On the other hand, the formation of furans can be explained by the ortho-ortho carbon coupling of phenoxy radicals at unsubstituted sites to form o, o'-dihydroxydiphenyl intermediate via its keto-tautomer, followed by $H_2O$ elimination. The pyrolysis temperature has also a substantial effect on the dimerized products quantities but little effect on the type of pyro-products. Moreover, the formation mechanism of pyro-products was suggested on the basis of products identified.

• The Korean Journal of Community Living Science
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• v.20 no.4
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• pp.503-514
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• 2009

The purpose of this study was to explore the influencing factors of consumption behavior of healthy functional foods including vitamin/mineral products for overweight and obese Koreans. Overweight and obese Koreans were selected based on the body mass index(BMI) from the KNHANES that was collected in 2007. Probit estimation model was used to find the influencing factors such as age, gender, job, education, income, nutrition education, and cultural capital(parents' education) on consuming the healthy functional foods. Overweight consumers were found to consume vitamin/mineral products and healthy functional foods at 17.5% and 22.7%, respectively. Obese consumers were found to consume vitamin/mineral products and healthy functional foods at 18.2% and 22.8%, respectively. In addition, self decision was found to be a significant factor to consume both products in both groups. Nutritional education and job were significant factors to consume vitamin/mineral products in overweight consumers, while mother's education and job(service) were significant factors in obese consumers. Weight control for body shape, gender, age, and income were significant factors to consume healthy functional foods in overweight consumers, while nutrition label and perceived health status were significant for obese consumers. Therefore, providing consumer information on functional foods might be useful for consumers to consider the healthy functional foods as an available option to purchase. Various influencing factors between two groups might be concerned to develop different strategies for promoting the healthy functional foods consumption including vitamin/mineral products.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.83-86
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• 2012

To support beneficial effects of makgeolli for human health, we investigated for the presence of 1,4-dihydroxy-2-naphthoic acid (DHNA), a bifidogenic growth stimulator (BGS), from commercial makgeolli products. Among eleven makgeolli products (A~K), four showed positive peaks for DHNA in high performance liquid chromatography analysis. Makgeolli product A in particular contained the highest concentration of DHNA (0.44 ppm), as confirmed by liquid chromatography-mass spectrometry. Furthermore, BGS activity of the makgeolli product A was higher than those of products in which DHNA was not detected. These results indicate that makgeolli can be a good source for DHNA and that DHNA-enriched makgeolli could be developed by modifying manufacturing procedures and controlling its microbiota.

• International Journal of Concrete Structures and Materials
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• v.8 no.1
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• pp.61-68
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• 2014

This paper reports the physical properties and hydration products of slag cement that was prepared by activating ground granulated blast furnace slag with commercial lime and plaster of Paris (POP) as activators. The consistency, setting times and soundness of various mixes of slag-lime-POP is reported. The hydration products and formation of bonds in the paste during setting were studied with the help of SEM, FTIR and XRD tests and the same are correlated to the hydration process. The setting times of the mixes are found to be lower than that of the value prescribed for ordinary Portland cement (OPC). Borax is used as a setting retarder and a borax content of 0.4 % by mass gives setting times that are normally prescribed for OPC. In the early stages of setting C-A-S-H gels are found in this cementing material instead of C-S-H gel, as generally observed in the OPC.

• Korean Journal of Pharmacognosy
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• v.37 no.3
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• pp.162-168
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• 2006

The isolation and identification of a new xanthone (6-0-palmitolyl-1,6-dihydroxy-5,7-dimethoxyxanthone) along with n-alkanols, fatty acids, 1,6-dihydroxy-5,7-dimethoxyxanthone, 1,7-dihydroxykanthone, betulinic acid, ${\beta}-sitosterol$, methyl 4-hydroxybenzoate, quercetin, and kaempferol from the aerial parts of Hypericum ascyron was reported. The structures were elucidated by spectroscopic methods, mainly NMR and mass spectrometry.

• Journal of Microbiology
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• v.39 no.4
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• pp.254-264
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• 2001

Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.