폴리머 모르터의 난연성 개선에 관한 연구

연규석,大濱嘉彦,김남길,김철영,지경용 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

불포화 에스트테르 수지의 큰 이용분야의 하나로 건축재료가 있으나 여기서 가장 문제로 되어 있는 것이 바로 난연성의 향상이다 불포화 폴리에스터수지는 탄소를 구성성분으로 하는 유기물이므로 무기재료와 같은 불연성을 기대하기는 어려우나 어느 정도까지는 연소를 억제시킬 수는 있다. 본 연구에서는 UP를 결합재로 하고 탄산칼슘을 충진재로, 규사를 잔골재로 하는 폴리머 모르터를 제조하고 이에 첨가되는 난연제량과 UP량을 각각, 5~12.5%, 12~24%로 변화시켜 난수별 난연특성을 고찰하였던 바, UP사용량에 따른 특정 난연제의 최적 사용량 범위를 얻을 수 있었다. One of the fields using the unsaturated polyester resin is the constructional material, but the most serious problem, in this field, is the incombustibility improvement. it is hard to expect the noncombustibility as in the inorganic materials for the unsaturated polyester resin since whose structural material is carbon, but the combustion can be controlled up to some degree. In this study the polymer mortars were made in which the unsaturated polyester resin as binder, the calcium carbonate as filler and the silica sand as fine aggregate. The incombustible characteristics were then investigated as varying the amount of the flame retarder and the unsaturated polyester resin from 5 to 12.5% and 12 to 24%, respectively. Based on the results, the optimized range of amount of flame retarder used with various amount of unsaturated polyester resin could be obtained.

Polystyrene Beads를 사용한 경량 폴리머 시멘트 모르타르의 기초적 성질

연규석,신영수,이윤수,이기원,황진하 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

polystyrene beads를 사용한 경량 시멘트 모르타르의 성질을 개선하기 위해 EVA혼화용 폴리머를 첨가한 모르타르를 제조하여, 물리ㆍ역학적 성질을 살펴보았던 바 polystyrene beads 골재 재부의 공극 때문에 높은 공기량을 보였고, 플로우 값은 폴리머-시멘트비 10%에서 가장 높은 값을 나타냈다. 또한 폴리머-시멘트비가 증가할수록 압축강도와 휨강도는 증가하였고, 시멘트-경량골재비가 낮을수록 압축강도는 증가하였으나, 휨감도에는 크게 영향을 주지 않았다. The objective of this study was to improve performance of lightweight polymer cement mortars by treating with redispersible polymer powders. Lightweight polymer-cement mortars were prepared with respect to different polymer-cement ratios, and tested for water absorption, specific gravity, flexural and compressive strengths, workability and freeze-thaw resistance. Manufactured lightweight polymer-cement mortars in this study showed lower specific gravity and lower thermal diffuseness than ordinary cement mortars. Water absorption, specific gravity, flexural, compressive strengths and workability were measured according to appropriate KS test methods. As a results, the optimum mix ratios for cement-aggregate, polymer-cement, and water-cement were found to be 1:3, 10% and 30%, respectively.

적산온도법에 의한 에폭시 모르터의 초기강도 예측에 관한 연구

연규석,大濱嘉彦,이윤수,김철영 강원대학교 부설 석재복합신소재 제품연구센터 1999 석재연 논문집 Vol.4 No.-

에폭시 모르터를 보수용으로 사용할 경우 거푸집의 회전율을 높이고 완전한 시공관리 차원에서 초기강도의 예측은 매우 중요하다 할 수 있다. 이에 본 연구는 결합재로서 에폭시 수지를 사용한 폴리머 모르터를 제조하고 경화제의 첨가량에 따른 초기강도의 변화를 시멘트 콘크리트에 적용되어 온 적산온도 방법에 의해 예측하는데 목적이 있다. 에폭시 모르터 제조에 사용된 재료는 반응성 희석제로 변성한 저점도형 Bisphenol-A계 액상 에폭시를 사용하였으며, 경화제는 지방족 Amine 변성 경화제를 사용하였다. 실험결과 에폭시 모르터의 기준온도는 -3∼-11℃로 나타났고, 경화제 첨가량에 따른 적산온도와 압축강도 사이의 강도 추정식은 다음과 같이 구할 수 있었다. 30% : Y = 292.42 Ln(M) - 881.16 40% : Y = 386.64 LN(M) - 1223.1 50% : Y = 273.18 LN(M) - 1040.5 Epoxy mortar is widely used to repair cement concrete structure and predicting strength of the mortar is of importance in its application. The objectives of this study were to compare the development of compressive strength of epoxy mortar with respect to maturity and to propose a predictive model for strength development of epoxy mortar. A series of tests were carried out for the hardener contents of 30, 40 and 50 percentage of resin and compressive strengths were measured at the age of 6, 12, 24, 72, 120 and 168 hours respectively under the cure temperature of 0, 10, 20 and 30℃. The datum temperature was estimated by measured strength, and the maturity was calculated with the estimated datum temperature. It was shown that the compressive strength of epoxy mortar could be predicted by regression analysis from the maturity-compressive strength relationship.

철원산 현무암을 이용한 폴리머 콘크리트의 물리·역학적 특성

연규석,이윤수,김철영 강원대학교 부설 석재복합신소재 제품연구센터 1999 석재연 논문집 Vol.4 No.-

이 연구는 철원지역에 분포하는 현무암을 대상으로 부가가치를 향상시킬 수 있는 상품을 개발하기 위한 기초자료를 얻기 위하여 현무암에 대한 암석학적 및 물리적. 화학적 특성을 규명하고자 하였다. 철원지역의 현무암은 크게 대다공상 조직과 소다공상 조직을 갖는 2가지 암상으로 구분할 수 있으며, 주로 사장석과 휘석류, 감람석, 불투명 광물 등으로 구성되어 있고, 일부 기공속에서는 석영과 방해석이 발견된다. 현무암의 비중(참비중)은 2.89∼2.94, 공극률과 흡수율은 각각 9.96∼13.7%, 4.01∼6.53% 값의 범위를 보였고, 마모감량은 24.7∼30.5wt.%, 일축 압축강도와 인장강도는 각각 536∼875㎏f/㎠, 53.7∼69.1㎏f/㎠의 값이므로, 강도의 경우 기공이 적은 현무암이 많은 현무암보다 약간 더 강한 것으로 나타났다. 현무암의 미량원소 함량중 Co, Cr, Ni 등의 함량은 KIoke(1979)가 제시한 농작물에 독성을 줄 수 있는 토양중의 최대 허용한계값 (Co 50 ppm, Cr 100 ppm, Ni 100 ppm) 보다 더 높은 값을 보여, 철원현무암을 석제품으로 가공할 때 생기는 미석분을 처리할 때에는 이러한 점을 충분히 고려하는 것이 바람직할 것이며, 현무암의 분말시료에 대한 양이온 교환 용량 값에 의하면 대다공상 현무암 (5.81meq/100g)의 경우 중금속 흡착제로 활용할 수 있는 가능성이 충분히 있어, 이에 대한 차후의 면밀한 연구가 필요할 것으로 판단된다. Feasibility of chulwon basalt as a coarse aggregate for polymer concrete was investigate to solve the environmental problems associated with the waste. Basalt aggregates were prepared and used to produce basalt polymer concrete. The concrete was tested for physical and mechanical properties. The tested properties of basalt polymer concrete were not different from those of normal polymer concrete. It was concluded that chulwon basalt could be used as an aggregate for polymer concrete production. However, the long-term behavior, thermal extension and durability of basalt polymer concrete were suggested to be further explored.

비정질 Fe1-x Px합금의 전기비저항

문영모, 연규황, 김택기 忠北大學校部設基礎科學硏究所 1987 自然科學硏究 Vol.1 No.1

-본문참고-

졸참나무 수피의 추출성분

김진규,이상극,함연호,배영수 江原大學校 森林科學硏究所 2002 Journal of Forest Science Vol.18 No.-

졸참나무 수피를 채취하여 아세톤:물(7:3, v/v) 혼합용액으로 추출하고 유기용매를 제거한 후 hexane, CH₂Cl₂, EtOAc 및 수용성으로 분획하여 등결건조하였다. 그 중에서 EtOAc용성 분획물을 MeOH 수용액 및 EtOH-hexane 혼합용액을 사용하여 Sephadex LH-20 칼럼크로마토그래피를 수행하여 (+)-catechin, ellagic acid, taxifolin, taxifolin-3-O-β-D-glucopyranoside를 단리하였다. 단리된 화합물의 구조는 ¹H, ^(13)C-NMR spectrum으로 구조를 구명하였다. The bark of Quercus serrata Thunb were collected, extracted with acetone-H~O(7: 3, v/v), fractionated with hexane, methylene chloride and ethylacetate, and freeze dried to give some dark brown powder. The ethylacetate soluble mixture was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. The isolated compounds from &. serrata were (1- 1-catechin, ellagic acid taxifolin and taxifoiin-3-O-ll-D-glucop~anos~de. The structures of isolated compounds were characterized by ¹H, ^(13) C-NMR spectroscopy.

AI 조성비 변화에 따른 GaAs/AIGaAs 다중양자우물구조 특성변화 연구

유연희,최정우,임재영,노삼규 慶熙大學校 材料科學技術硏究所 1998 材料科學技術硏究論集 Vol.11 No.-

We manufactured and characterized different sets of GaAs/AlGaAs multiple quantum well structures for the long wavelength infrared photodetection. The samples were grown by MBE. We changed the aluminum composition of barrier region from 0.24 to 0.30 in 0.02 steps, and performed double crystals X-ray diffraction(DCXRD) and the photoluminescence measurements. DCXRD measurements correctly gave the expected aluminum compositions. Photoluminescence measurements revealed that the ground state energy of the well increases with composition as desired, but the change was not very significant.

Clomipramine을 투여하여 치료된 강박장애 2례

김보연,이규환,채영래,이철,백인호 최신의학사 1990 最新醫學 Vol.33 No.1

위 전암성 병변에 대한 내시경적 추적 관찰

김규종,박선자,남지현,임현정,김지연,박무인,구자영 고신대학교 의학부 2005 高神大學校 醫學部 論文集 Vol.20 No.1

Background: The aims of this study were to investigate the endoscopic findings of precancerous lesions of stomach and to see whether or not these lesions could progress to the carcinoma. Method: May 2000 to February 2001, consecutive patients diagnosed as having chronic active gastrits (CAG), intestinal metaplasia (IM), dysplasia, adenoma by endoscopic biopsy were enrolled. A total of 359 patients were included in this study and endoscopically followed-up to Autust 2001. Results; Among all 33 patients (26 dysplasia, 7 dysplasia with adenoma) diagnosed as dysplasia by endoscopic biopsy, there were 6 chronic erosive gastritis (CEG), 6 chronic erosion, 17 adenoma, 4 R/O cancer. On follow-up endoscopic biopsy (17 patients), there were 3 IM, 4 dysplasia, 5 adenoma, 5 carcinoma. Among all 107 patients (53 IM, 38 IM with CAG, 14 IM with CEG, 1 IM with adenoma, 1 IM with dysplasia) diagnosed as IM by endoscopic biopsy, there were 52 CEG, 33 chronic erosion, 6 local lesion, 5 adenoma, 5 R/O cancer, 3 gastric polyp, 3 atrophy with IM> On follow-up endoscopic biopsy (25 patients), there were 2 chronic gastritis, 1 CEG, 3 CAG, 14 IM 3 dysplasia, 2 adenoma, 1 carcinoma. Among all 185 patients (147 CAG, 37 CAG with IM, 1 CAG with adenoma) diagnosed as CAG by endoscopic biopsy, there were 86 CEG, 62 chronic erosion, 4 local lesion, 10 adenoma, 16 R/O cancer, 4 gastric polyp, 2 IM, 1 chronic gastritis. On follow-up endoscopic biopsy (35 patients), there were 8 chronic gastritis, 3 CEG, 14 CAG, 5 IM, 2 dysplasia, 1 adenoma, 2 arcinoma. Among All 34 patiets (22 adenoma, 8 adenoma with low grade dysplasia, 2 adenoma with moderate grade dysplasia, 2 adenoma with high grade dysplasia) diagnosed as gastric adenoma by endoscopic biospy, there were 1 local lesion, 24 adenoma, 2 R/O cancer, 7 gastric polyp. On follow-up endoscopic biopsy (17 patients), there were 2 CEG, 2 low grade dysplasia, 1 high grade dysplasia, 4 adenoma 1 adenoma with dysplasia, 4 adenoma with low grade dysplasia, 2 adenoma with high grade dysplasia, I cancerous change. Conclusions: Althought it was short period, there were some of cancerous change in precancerous lesions at follow-up endoscopy. This study suggests that screening for precancerous lesions, is one method of improving the prognosis of gastric carcinoma and when the precancerous lesions are diagnosed on endoscopy, serial endoscopic follow-up should be done to find early gastric cancer.

백서의 복강내에 투여한 Mitomycin-C-Polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

송규상,강대영,최정목,노승무,정경수,오정연,김진향,양준목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To evaluate the in-vivo effects of mitomycin-C-polyglycolic acid composite(MMC-PGA) the disk: shaped composite were implanted into the peritoneal cavity of the Sprague-Dawley rats. The pathologic changes were examined at various time points up to 12 weeks. Initially the soft tissue around the inserted disks showed capillary congestion at 3 days. Inflammatory infiltrates with foreign body giant cells appeared from the 2nd week and reached peak response at 6-8 weeks. These reaction diminished prominently at 12 weeks. No specific pathologic change was found in the liver, the kidneys, and the heart. The above results suggest that the MMC-PGA composite can serve as a new device for intraperitoneal chemotherapy of various types of cancers.