• 생명과학회지
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• 제7권3호
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• pp.186-191
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• 1997

수정된 선별법(modified selection method)을 사용하여 candiosis에 대한 새로운 생리활성물질(anticandiosis agent)을 생성하는 미생물을 분리하여Streptomyces sp. S627이라 명명하였으며, 이균의 발효액으로부터 methanol추출, diaion Hp-20, silica gel chromatography, 및 분취용 TLC 등의 방법을 사용하여 물리화학적 특성이 다른 S-637(A)와 S-627(B)을 분리하였다.

• Bulletin of the Korean Chemical Society
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• 제16권6호
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• pp.507-511
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• 1995

Catalytic chlorination of chlorobenzene was studied in vapor phase using various solid-acid catalysts such as silica-alumina, alumina, zeolite and a modified clay prepared by impregnating bentonite with ferric chloride. The conversions of both chlorine gas and chlorobenzene showed high over silica-alumina, alumina and modified clay catalysts. However relatively large amounts of polychlorinated benzene derivatives were also observed. The active species of catalytic activity in chlorination of chlorobenzene in vapor phase were proved to be as Lewis acid sites by in-situ IR experiments. The strength of Lewis acid sites which were effective for the vapor-phase chlorination seemed to be having Hammett acidity Ho >-3.0. The selectivity to dichlorobenzenes was proved to be high over the zeolite catalyst due to their shape-selective properties. p-Dichlorobenzene or dichlorobenzene selectivities were improved more or less by changing the reaction conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.475-476
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• 2012

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.27-28
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• 2006

Chromatographic separation of enantiomers by high-performance liquidchromatography (HPLC) has considerably advanced in the past two, and many optically active polymers have been developed to be usedaschiral stationary phases (CSP). Among many CSPs, cellulose-andamylose-based CSPs are most attractive from the viewpoints of theirwide applicability and easy availability. The polysaccharides are readily modified to ester and carbamates. The derivatives have been used as CSPs after being coated on macroporus silica gel. Here, the CSPs based on phenylcarbamate derivatives of these two polysaccharides will be mainly discussed. The immobilization of the derivatives on silica gel will also be discussed.

• Korean Chemical Engineering Research
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• 제46권4호
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• pp.722-726
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• 2008

실리카 microsphere는 HPLC를 위한 흡착 충진제와 같은 용도로 사용하기에 적합한 혁신적인 소재로 널리 알려져 있다. microsphere을 기능성고분자나 금속, 생리활성 물질과 같은 특정한 성질을 지닌 물질로 표면 개질시키므로 다양한 용도로 활용할 수 있다. 콜라겐은 생체조직을 구성하는 기본 단백질로 생체적합성이 뛰어난 물질로 주목받고 있는 기능성 소재이다. 본 연구에서는 50% 이상의 세공부피를 지닌 다공성 silica microsphere를 고분자 응집법인 PICA 법을 이용하여 colloidal silica로부터 제조하고 콜라겐 hydrogel을 사용하여 표면 개질시키므로 생체적합성을 증진시키는 방법을 연구하였다. 실리카/콜라겐 microsphere 에 은 나노입자를 담지시킨 microsphere 복합체를 만들고 특성을 조사하므로 생체소재로의 활용 가능성을 조사하였다.

• 대한화학회지
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• 제52권2호
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• pp.148-154
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• 2008

2-Propylpiperidine-1-carbodithioate(PPCD)I 로 수식화한 octadecyl로 결합된 실리카 막 디스크로 구리(II) 이온의 잔유양의 추출과 간단하고 빠르게 원자흡수분광법(AAS)으로의 정량법을 소개한다. 추출효율과 흐름속도, pH, 형 태, 벗김 산의 가장 적은 양에 대해 연구되었다. Anthraquinone 유도체의 2 mg로 수식한 막디스크의 최대 용량은 425 μg Cu2+ 이었다. 제안한 방법의 검출한계는 7 ng/ml이다. 이 방법은 다른 시료와 온천수 시료로부터 Cu2+의 회수에 적용하 였다.

• 폴리머
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• 제31권2호
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• pp.111-116
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• 2007

폴리우레탄 변형 아크릴레이트(PUA)/실리카 하이브리드 필름은 자외선 경화에 의해 제조되었고, 필름의 표면물성은 경도시험과 접착력 테스트를 통해 분석되었다. 이들 필름은 유기, 무기함량을 mole비로 조성하여 실험하였으며, 무기조성은 실리카 입자의 함량을 기준으로 설정하였다. 필름 층 내의 실리카 입자는 함량에 따라 혹은 분산정도에 따라 내스크래치성이나 필름자체 경도 등의 물성이 많은 차이를 보였는데, 이는 PUA필름 층 내의 실리카 입자들이 균일하게 분포되어 가교결합되어 있었기 때문이다.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1557-1561
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• 2006

The use of chemically modified silica-salen$(NEt_2)_2$ was studied for the separation and concentration of the metal ions from an aqueous solution by a solid phase extraction. After the salen(NEt2)2 was synthesized, it was chemically bonded to silica gel by a diazonium coupling reaction. The adsorption capacities and binding constants were obtained with respect to Cu(II), Mn(II), Pb(II) and Zn(II) by a graphical method. Some experimental conditions were optimized for the determination of the trace elements. After the silica-salen(NEt2)2 was pulverized in a sample solution of which the pH was adjusted, the solution was stirred to pre-concentrate the metal ions. The metal ions adsorbed were desorbed with nitric acid solution. And the concentrated analytes were determined by a flame AAS. The method proposed here was so rarely influenced by a sample matrix that the procedure was applied to 3 types of water samples. The reproducible results of less than 10% RSD were obtained at the concentration level of ca. 100 ng/mL and the recoveries of 95-109% were obtained in the spiked samples in which given amounts of analytes were added.

• 한국전기전자재료학회논문지
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• 제25권8호
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• pp.657-663
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• 2012

The spherical mesoporous silica is synthesized and incorporated with CdSe/ZnS quantum dots(QDs) for preparing micro beads to detect toxic and bio-materials with high sensitivity. The spherical silica beads with the brunauer-emmett-telle(BET) average pore size of 15 nm were prepared with a ratio 1, 3, 5-trimethylbenzen, as a swelling agent, to the block-copolymer template surfactant of over 1 and under vigorous mixing condition. The surface of spherical mesoporous silica is modified using octadecylsilane for incorporating QDs. Based on photoluminescence(PL) spectra, the relative brightness of mesoporous silica beads incorporated with 10 nM of QDs is 79,000 times brighter than that of Rodamine 6 G.

• Elastomers and Composites
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• 제53권1호
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• pp.6-12
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• 2018

Styrene-butadiene Rubber (SBR) Latex composites, incorporated with cellulose/starch-silica hybrids synthesized by gel-adsorption method, were filled into rubber by the latex compounding method. The structure morphology, mechanical properties, and thermodynamic properties of gel-silica hybrids were characterized. The states of hybrids which used as fillers were also characterized by SEM. As the fillers ratio increased, the difference for storage modulus of samples had been morphology by rubber process analyzer (RPA). Then, as more fillers ratio was filled into the matrix, the best tensile strength result, and the largest modulus value were also proved by UTM and RPA. As for thermal stability, increase in the ratio of fillers led to higher initial decomposition temperature, which was also proved by TGA. The swelling ratio of samples has also been characterized. From the results of all the tests, cellulose-silica hybrid showed the best results as a filler, and the best filling ratio of this hybrid is about 10 phr, which has the best storage modulus and great tensile strength.