• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2003.10a
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• pp.43-43
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• 2003

• Journal of the Korean Chemical Society
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• v.32 no.2
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• pp.149-155
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• 1988

Pentasil zeolites, including ZSM-5, ZSM-8, ZSM-11 and silicalites, were synthesized using various organic cations. Synthesis run was carried out in a Parr pressure reactor of $2{\ell}$ capacity and a self-constructed reactor with a magnetic stirring system. The reactant materials used are colloidal silica (Snowtex), sodium aluminate, sodium chloride, TEA, TPA, TBA, Choline and water. The composition of starting materials and the reaction temperature were found to be important factors for the synthesis of uniform pentasil zeolites.

• Journal of Life Science
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• v.23 no.1
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• pp.84-94
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• 2013

The cytotoxicity of coffee-like green tea (CLGT) was determined in a human breast cancer cell line, MCF-7; a human prostate cancer cell clone, PC-3; a human neuroblastoma cell line, SK-N-SH; and a rat cardiomyoblast cell line, H9c2, with reference to green tea leaves (GTL). The CLGT was prepared by roasting the GTL for 60 min at $240^{\circ}C$ in a temperature-controlled frying pan. The CLGT preparation imitated the flavor and taste characteristics of coffee fairly well according to sensory analysis. The CLGT preparation had no adverse cytotoxic effects on the cancer cells or the normal cells compared to GTL. No significant change in the antioxidant activity was seen in the CLGT preparation compared to that of GTL. The amount of total protein, sugar, and phenolic compounds was reduced in the preparation relative to those in GTL, a fact that might explain the coffee-like flavor and/or taste characteristics of the CLGT preparation. These results suggest that CLGT prepared by roasting GTL for 60 min at $240^{\circ}C$ does not show any adverse effects on cancer cells and normal cells compared to GTL. They imply that CLGT could be safe for human consumption.

• Korean Journal of Materials Research
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• v.15 no.5
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• pp.334-339
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• 2005

Nickel Powders were synthesized by the reduction of $Ni(OH)_2$ reactant slurries from nonaqueous media, and the morphological characteristics of nickel powders with the addition of NaOH, the composition of mixed solvents, reaction temperature and reaction time were investigated. The NaOH addition changed the structure of agglomeration in the submicron range. As the volume ratio of TEA to DEA increased, the powders slightly suppressed the agglomeration between particles and their size increased. The reaction temperature on size and shape of nickel powders was significant. As reaction time was shortened from 40 min to 0.3 min at $220^{\circ}C$, size distribution of nickel powders was transferred to a narrow size distribution owing to the presence of smaller particles with below $1.0\;{\mu}m$.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.530-534
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• 1993

The present study was conducted to investigate nitrite-scavenging ability of the components of traditional tea materials in Korea. The nitrite-scavenging ability was appeared in all the samples examined. Ethanol soluble fractions obtained from water soluble fractions of Cassiae torae semen, Perilla semen, Acantopanacis cortex and Zingiberis rhizoma exhibited higher the nitrite-scavenging effect than ethanol precipitate frecipitate fractions. While opposite results were obtained from those of Zizyphi fructus, Chaenomelis fructus and Schizandrae fructus in the nitrite-scavenging effect.

• Food Science and Preservation
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• v.16 no.6
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• pp.924-928
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• 2009

Green tea has been shown to have multifunctional health-promoting properties including cholesterol level control an antidiabetic effect and anticancer, antioxidant, and antimicrobial properties, inboth in vivo and in vitro experiments.We earlier reported antifungal and antibacterial effects of green tea extract by investigating cell membrane functions. The purpose of the present study was to purify and identify antimicrobial substances from green tea extract. Such materials were extracted from green tea (Camellia sinensis. var. sinensis) and purified by high-performance liquid chromatography. The antimicrobial substances in the extract were identified as epicatechin gallate and epigallocatechin gallate by nuclear magnetic resonance spectrophotometry.

• Journal of Life Science
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• v.18 no.2
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• pp.273-278
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• 2008

Various biological resources from plants, animals, mushrooms, microorganisms, and foods were tested for the inhibitory activity against squalene synthase (SQS). Among 32 samples, more than one fourths (9 samples) exhibited significant SQS inhibitory activity. Interestingly, SQS inhibitory activity was detected in the samples such as green tea, fermented soybean paste, and plum juice. The SQS inhibitory activity of green tea was not only high but also stable. Its SQS inhibitors were supposed to be catechin derivatives, which have been known to be main bioactive components in green tea. The galloyl catechins showed higher SQS inhibitory activity compared to the nongalloyl catechins. Especially, (-)-epigallocatechin gallate appeared to be strongest inhibitor against squalene synthase ($IC_{50}=90{\mu}M$).

• Journal of Nutrition and Health
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• v.12 no.1
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• pp.69-75
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• 1979

Stevia rebaudiana Bertoni M. can be cultivated in Korea as a new sweetness resource. It seems possible that stevioside the sweet substance extracted from the leaves of Stevia rebaudiana Bertoni M. can be used instead of saccharin. In order to obtain the fundamental data due to natural sweetening materials used of as additives to food stuffs such as coffee and tea etc. It was investigated to reduce the calories from coffee and tea without reducing the conventional sweetness, drinks sweetened with mixtures of stevioside and sucrose were prepared. The results obtained are as follows: 1) Mixture of 50% stevioside 40 mg (0.04%) (A) and 1.5% sucrose, 95% stevioside 20 mg (0.02%) (B) and 2.0% sucrose, and 50% stevioside 60 mg (0.06%) (A) and 95% stevioside 40 mg (0. 04%) (B), the sweetness of which in coffee corresponded to that of 7% sucrose in the drink, was prepared. 2) Mixture of 50% stevioside 60 mg (0.06%) (A) and 1.5, 2.0, 2.5% sucrose, 95% stevioside 40 mg (0.04%) (B) and 1.5, 2.0% sucrose, and 50% 80 mg (0.08%), 95% 60 mg (0.06%) (A,B), respectively the sweetness of which in tea corresponded to that of 7% sucrose in the above drink, was prepared. 3) Sucrose saving of 21.42-28.57% compared to equally sweet sucrose-sweetened coffee and tea could be achieved without deterioration of other taste qualities.

• Journal of Chest Surgery
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• v.44 no.2
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• pp.178-182
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• 2011

Background: We analyzed the results of surgical reduction and fixation of ribs under thoracic epidural anesthesia and analgesia (TEA) in patients who had no more than 3 consecutive rib fractures with severe displacement to examine the clinical usefulness of this method. Materials and Methods: From May 2008 to March 2010, 35 patients underwent surgical reduction and fixation of ribs under TEA. We reviewed the indications for this technique, number of fixed ribs, combined surgical procedures for thoracic trauma, intraoperative cardiopulmonary events, postoperative complications, reestablishment of enteral nutrition, and ambulation. Results: The indications of TEA were malunion or nonunion of fractured ribs in 29 (82.9%; first operation) and incompletely ribs under previous general anesthesia in 6 (17.1%; second operation). The average number of fixed ribs per patient was 1.7 (range: 1~3). As a combined operation for thoracic trauma, 17 patients (48.6%) underwent removal of intrathoracic hematomas, and we performed repair of lung parenchyma (2), wedge resection of lung (1) for accompanying lung injury and pericardiostomy (1) for delayed hemopericardium. No patient had any intraoperative cardiopulmonary event nor did any need to switch to general anesthesia. We experienced 3 postoperative complications (8.6%): 2 extrapleural hematomas that spontaneously resolved without treatment and 1 wound infection treated with secondary closure of the wound. All patients reestablished oral feeding immediately after awakening and resumed walking ambulation the day after operation. Conclusion: Thoracic epidural anesthesia and analgesia (TEA) may positively affect cardiopulmonary function in the perioperative period. Moreover, this technique leads to an earlier return of gastrointestinal function and early ambulation without severe postoperative complications, resulting in a shortened hospital stay and lowered costs.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.49-61
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• 2012

This study was carried out to investigate the chemical composition and the inorganic constituents of the green tea at the 3 picking periods (Ujeon, Sejag, Jungjag) in Hadong. The results as follows ; The contents of chlorophyll, tannin, vitamin-c and total catechin were increased as picking periods increased but the contents of total nitrogen, total free amino acids, theanine and caffeine were decreased on the reverse. The inorganic constituents Mg, Ca and Mn were increased as picking periods getting late but the Na, K, B contents were decreased on the reverse. The contents of the total nitrogen, chlorophyll, total free amino acid, theanine, caffeine and total catechin and Na, Mg, Ca, B and Se were insignificant differences between Ujeon and Sejag.