• 대한화학회지
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• 제11권2호
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• pp.45-50
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• 1967

有機할로겐化合物의 分離方法으로써 試料의 中性子照射에 依한 放射化 Thin Layer Chromatography를 Methanol을 展開溶媒로 하여 硏究한 結果 各種 할라이드, 할로겐酸, 할로겐알데하이드 等에서 銳敏한 展開 peak를 얻었으며 混合物의 展開에서도 定性確認에 充分한 分離 peak를 얻었다. 多 할로겐化合物, 芳香核鹽化物에 있어서는 試料의 中性子線 照射에 依하여 한 個 以上의 放射化할로겐化合物이 生成되어 確認이 困難하였으며 其他 할로겐 化合物에서는 再現性있는 Rf値를 얻을 수 있었다. 그리고 實驗方法을 記述하고 本 方法의 有用性에 關하여 論議하였다.

• 대한의생명과학회지
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• 제23권4호
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• pp.388-394
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• 2017

Recently, coffee is the most popular beverage for modern people. A great number of substances are found in coffee beans and have been studied for many years such as aliphatic and aromatic compounds. However, studies on the physiological activity of coffee extracts are insufficient. This study was performed to determine the contents of caffeine and chlorogenic acid in coffee extracts according to the solvent and to investigate the physiological activity of coffee extracts. Coffee extracts were extracted by ultrasonication method with various types of solvents including distilled water, ethanol, and other organic solvents under $50^{\circ}C$ and $80^{\circ}C$. The contents of caffeine and chlorogenic acid in coffee extracts were determined by Liquid Chromatography-Mass Spectrometry (LC-MS). Also, cytotoxic and antioxidative effects of coffee extracts were evaluated with MTT and DPPH assays to analyze the physiological activity. As a result, it was confirmed that caffeine and chlorogenic acid contents were extracted in distilled water with the highest rate. Antioxidative activity was observed below 10-fold dilute of coffee extracts, however cytotoxicity was not observed. In conclusion, distilled water was the best solvent for extracting caffeine and chlorogenic acids from coffee bean with ultrasonication and these coffee extracts are less cytotoxic in human skin cell lines and have antioxidant effect.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.768-778
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• 2011

Calixpyrroles and related macrocycles are non-planer synthetic anion receptors that have attracted considerable attentions in recent years. Although the synthesis of calix[4]pyrrole (known as meso-octamethylporphyrinogen) was reported more than 100 years ago, the anion binding properties were first discovered in 1996. The simple calix[4]pyrroles can be synthesized in single step in high yield by condensation of pyrrole with acetone. The compounds showed preferential binding for halide anions including fluoride, phosphate, carboxylate, and chloride in organic media. Efforts to improve the anion affinity of calix[4]pyrrole and to enhance its selectivity have led to the synthesis of a variety of new calixpyrrole derivatives. Among the various modifications, introduction of straps on one side of the calix[4]pyrroles are the most effective. Incorporation of aromatic rings other than pyrroles also exhibited interesting binding behaviour. Introduction of signalling units as part of the strapping element enable to detect the anions on chromogenic or fluorogenic fashion. Finding of the anion transport properties across the membrane and cytotoxic effects of the calix[4]pyrroles open new window for calixpyrrole-related research. The polymer-incorporated systems have also been employed as anion complexants in solvent-solvent extraction. These old, yet easy-to-make macrocycles have well advanced more recently with the discovery of the ion-pair complexation properties. In this review, the synthetic developments and anion binding properties of calixpyrroles for the last decades will be discussed and will cover the advances in calixpyrrole chemistry.

• 한국의류학회지
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• 제23권6호
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• pp.809-819
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• 1999

The scientific analysis of buried fabrics from the 16th century tomb of Kim HeumJo was conducted focusing on the conservation of fabrics, In order to find out the appropriate cleaning solvent and detergent for historical textiles physical chemical and biological analysis was conducted. The following results are obtained from this study : 1, The buried fabrics from the tomb of Kim HeumJo were composed of cotton silk and ramie. Most of fabrics had lost their original colors faded to brown. It was revealed variations in weaves and patterns were very developed at that times. 2. The chemical components of soils are hydrocarbons alkyl alcohols nitrogen compounds aromatic organic acid which is supposed to be from a human body microorganisms and their by-products. 3. Seven kinds of fungi Actinomycetes Corynebacterium spp Micrococcus luteus Bacillus Clostridium were isolated from the fabrics. The most common fungus was Bacillus.

• 한국인쇄학회지
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• 제15권1호
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• pp.57-69
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• 1997

The field of printing to use pressurized ink using screen gossamer that is called screen printing. Existing cleaning solvents for the screen printing are the organic solvents containing aromatic compounds and stench. Also, Cleaning method of screen printing are for the most part mixed cleaning method of dipping and polish. In this study, we measured the cleaning efficiency by gravimetric analysis and the property change of gossamer by image analyzer using existing cleaning solvent. Also, we investigated a new cleaning process showing excellent cleaning efficiency using the ultrasonic and vibration cleaning method instead of the exsiting mixed cleaning method.

• 대한화학회지
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• 제22권3호
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• pp.184-193
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• 1978

Styrene-divinylbenzene 공중합체를 이황화탄소 용매 속에서 무수염화알루미늄과 반응시켜 염화알루미늄${\cdot}$고분자촉매를 합성하여 이들의 형태를 광학현미경, 주사전자현미경으로 조사하고 원자흡광 및 electron microprobe X-선으로 분석하였다. 각종 유기산과 지방족 및 방향족 알코올과의 에스테르화반응에서 염화알루미늄${\cdot}$고분자촉매의 효과에 관하여 연구하였다.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.787-792
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• 2011

Under mild conditions and without any additional organic solvent, synthesis of carbamatoalkyl naphthols could be carried out in the present of two halogen-free Br${\phi}$nsted acidic ionic liquids, 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate and N-(4-sulfonic acid)butylpyridinium hydrogen sulfate. A wide range of aromatic aldehydes easily undergo condensation with $\beta$-naphthol and methyl or benzyl carbamate to afford the desired products of good purity in excellent yields. The present methodology offers several advantages such as a simple procedure with an easy work-up, short reaction times, and excellent yields. The catalysts could be recycled and reused for several times without substantial reduction in their catalytic activities.

• Bulletin of the Korean Chemical Society
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• 제20권6호
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• pp.677-682
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• 1999

Conjugated polycarbosilanes with diacetylene and aromatic groups of thiophene or phenylene simultaneously present in the polymer backbone such as poly[[1,4-bis(thiophenyl)buta-1,3-diyne]-alt-(dimethylsilane)], poly[[1,4-bis(thiophenyl)buta-1,3-diyne]-alt-(diphenylsilane)], poly[[1,4-bis(phenyl)buta-1,3-diyne]-alt-(dimethylsilane)],and poly[[1,4-bis(phenyl)buta-1,3-diyne]-alt-(diphenylsilane)] have been prepared. The characteristic C=C stretching frequencies appear at 2177-2179㎝-1 in the IR spectra of the polymers. The molecular weights of these polymers were detemined by GPC. All of these materials are soluble in organic solvents such as THF and chloroform, and thermally stable up to 200℃ in general without any weight loss under nitrogen. The prepared materials in THF solvent show a maximum absorption peak in the range of 334-356 nm with a molar absorptivity of 10³∼10ⁿ(n=5)L/(cm·mol) in the UV-visible absorption spectra. A maximum emission peak in the range of 403-550 nm is also observed in the fluorescence emission spectra. Both absorption and emission spectra strongly indicate that the obtained polycarbosilanes contain the new conjugated systems along the polymer main chain.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.266-272
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• 2010

Natural Ginger extract was extracted from Ginger component using ethanol as a solvent, and we tested various pharmaceutical characteristics in this extract. Characteristics experiment to use natural Ginger extract tested antimicrobial experiment using microbe, and analyzed organic and inorganic component with analysis instrument. From the result of characteristics experiment, some conclusions are obtained as follow. In this experiment, natural Ginger extract was obtained about 22.50 g-Ginger extract(extraction ratio : 1.80%) as liquid state of some viscous yellow-brown color. The result of antimicrobial experiment with staphylococcus aureus and aspergillus niger in microbe decreased more and more according to passage of reaction time. This phenomenon could know that Ginger extract has influenced to antimicrobial effect. In the result of instrumental analysis, aromatic organic components of benzimidazole(1.283), propyl isothiocyanate or isothiocyanic acid(1.477) etcs from Ginger extract were detected with GC/MS and inorganic component of Ca(27.6 ppm), K(24.08 ppm), Mg(6.03 ppm), Na(1.02 ppm), Zn(1.02 ppm), Sb(0.711 ppm) and Li(0.079 ppm) etcs from Ginger extract were detected with ICP/OES.

• 펄프종이기술
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• 제35권1호
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• pp.27-32
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• 2003

To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.