고분자형 자외선 안정제를 함유한 SBR과 NR의 UV 노화 거동에 관한 연구

남경태 ( Kyoung Tae Nam ),홍창국 ( Chang Kook Hong ),채규호 ( Kyu Ho Chae ),강신영 ( Shin Young Kaang ) 한국고무학회 2006 엘라스토머 및 콤포지트 Vol.41 No.3

본 연구에서는 고분자형 자외선 안정제 DGEBA-HALS의 광분해 억제 효과를 평가하기 위해 SBR과 NR 고무를 사용하여 광안정제 첨가에 따른 UV 조사 영향을 고찰하였다. 이를 위해 광안정제를 첨가하지 않은 배합고무, 사용화된 광안정제인 Cyabsorb UV-3529를 첨가한 배합고무, 그리고 고분자형 DGEBA-HALS를 첨가한 배합고무의 영율, 인장장고, blow-off 변형, 가교밀도 측정을 통한 시편의 물리적 특성변화 등을 관찰하였다. UV 조사 후 모든 시편에서 영율이 증가하였으며 인장강도는 광안정제를 첨가한 시편이 첨가하지 않은 시편보다 우수했다. 특히 NR의 경우 DGEBA-HALS 첨가 시 인장강도가 향상되었다. Blow-off 변형 실험결과도 영율 실험 결과와 비슷하였다. UV-vis transmissinon spectra를 통한 SBR 배합고무의 투과도를 조사한 결과 광안정제를 첨가함으로써 약 4%의 향상된 투과도를 보였다. Cyabsorb UV-3529와 DGEBA-HALS의 첨가는 비슷한 경향의 투과도를 나타내었다. SEM을 통해 시편의 표면을 관찰한 결과 광안정제를 첨가함으로써 UV 조사에 의한 균열의 크기가 작아짐을 알 수 있었고, 특히 DGEBA-HALS는 상용화된 Cyabsorb UV-3529 보다 더 좋은 광분해 안정효과를 갖는 것을 확인할 수 있었다. The retardation effects of a new polymeric UV stabilizer, DGEBA-HALS, on the UV degradation of SBR and NR were investigated in this study. The UV degradation behaviors of three different rubber compounds, without any photostabilizer and with commercial Cyabsorb UV-3529 and DGEBA-HALS, were compared. Also, the physical characteristics such as Young`s modulus, tensile strength, blow-off deformation and crosslink density were examined. The Young`s modulus was increased by UV irradiation for all samples, and the tensile strength, after UV irradiation, of the compound with UV stabilizer was better than that of the compound without stabilizer. Especially, the tensile strength of UV irradiated NR was improved by adding DGEBA-HALS. The results of blow-off deformation were in accord with those of Young`s modulus. The degree of transmission of SBR compounds obtained from UV-vis transmission spectra was improved about 4% by adding the UV stabilizer. Commercial Cyabsorb UV-3529 and DGEBA-HALS showed similar trends of transmission. The SEM photographs of SBR surface showed that the size of cracks created by UV irradiation became smaller by adding UV stabilizer. In particular, it is observed that the stabilization effect of DGEBA-HALS was better than that of commercial Cyabsorb UV-3529.

쓰레기 매립장 주변 농촌 주민들의 삶의 질 연구

이명경,최준열,김인경,조영아,김영신,정혜진,김리나,이영규,조영태,Lee, Myung-Kyung,Choi, Jun-Yeol,Kim, In-Kyoung,Cho, Yeong-Ah,Kim, Young-Shin,Jung, Hye-Jin,Kim, Li-Na,Lee, Young-Kyu,Cho, Young-Tae 대한예방의학회 2006 예방의학회지 Vol.39 No.4

Objectives: This study aims to examine if a garbage dumping site has real and negative influence on the quality of life (QOL) for the nearby residents. The net effects of the residential distance from the garbage dumping site and from the garbage truck route were investigated for five domains of the QOL. Methods: Two hundred fifty seven Shin-dong Myeon residents, Chun-cheon Si, participated in a self-administrated survey. The Shin-dong Myeon garbage dumping site began operating in 1996. ANCOV A with generalized linear models and multiple regression analysis were performed. Results: Descriptive analyses show that a residence nearby a garbage dumping site is negatively associated with the physical and environmental domains of the QOL. The residential distance from the garbage truck route does not exert any significant effect on various domains of QOL, except for the environmental domain. On the multivariate analysis, the residents living near the garbage dumping site tended to have a significantly negative QOL in the physical and environmental domains. However, the distance from the garbage truck route did not show a significant nor substantial effect on the QOL. The demographic and socioeconomic control variables are associated with a number of the QOL domains, and their patterns are consistent with the general expectations. Conclusions: The results indicated that a garbage dumping site is considered to be an environmental hazard among the nearby residents according to the lower scores on the physical and environmental domains of the QOL. The findings from this study provide comprehensive understanding on the residents' QOL, and they may help politicians and policy makers make decisions for appropriate interventions.

계면활성제 함유 인지질 나노입자의 초가변성 연구

신지영,오유경,강민정,권경애,김종국 한국약제학회 2003 Journal of Pharmaceutical Investigation Vol.33 No.3

This study was aimed to formulated various phospholipid nanoparticles composed of different surfactants and to evaluate the deformability of the phospholipid vesicles as candidates of useful ultradeformable nanoparticles. In vitro deformability of the hospholipid nanoparticles was studied using an extruder under a certain pressure. The sizes of phospholipid nanoparticles, passed volumes, and concentrations of the phospholipids in suspensions before and after extrusion were measured. The deformability indexes were estimated by using passed volumes, sizes of phospholipid nanoparticles and concentrations of phospholipids. Conventionl liposomes, placed under a certain pressure of an extruder, showed no passed volume indicating little deformability. Similar to conventional liposomes, phospholipid nanoparticles containing surpactants such as sodium taurcholate, Myrj 45, or Myrj 53 showed little deformability. In contrast, phospholipid nanoparticles composed of Tween 20, triton X-100, or sodium deoxycholate showed higher deformability indexes than others. Taken together, the deformability of phospholipid nanoparticles could be significantly affected by the type of surfactants. Moreover, these results suggest that the deformability of phospholipid nanoparticles could be modulated by surfactants.

배양 조건이 Candida albicans의 phospholipase 생성에 미치는 영향

신운섭,이경호,박주영,고춘명 대한의진균학회 1997 대한의진균학회지 Vol.2 No.2

Background : The dimorphic yeast, Candida albicans, is considered as a dangerous opportunistic pathogen in immunocompromised hosts. Several phospholipases of C. albicans are known to be secreted into the culture medium. Phospholipases have been proposed as a virulence factor in the pathoenesis of Candida infections. Objective : In order to investigate enzyme production, we examined culture condition of secreted phospholipase production from C. albicans. Methods : C. albicans ATTCC 10231 was cultivated in various media at 37℃ for 3 days. Phospholipase activity was measured by fatty acid soap precipitaiton in plate containing 0.04T lecithin, 0.1 M citrate buffer, pH 4.2 and 1.5% noble agar. Results : Phospholipase was highly induced when C. albicans was cultivated in broth medium(containing glucose 2%, albumin 0.2% and Fe^++ ion 0.01%) and Saboulaud's dextrose agar supplemented with 0.01% sodium deoxycholate. Conclusion : Highly induction of secreted phospholipase by albumin from C. albicans may be play an importans role in tissue invasion in the pathogenesis of C. albicans.

경계층 난류박리의 제어에 관한 연구 : 제1보;매끄러운 2차원 디퓨저 벽면에서의 난류박리특성 First Report;Turbulent Separation Characteristic on the Smooth 2-Dimensional Diffuser Wall Surface

신정관,박종일,이한영,김경훈 경희대학교 산학협력기술연구원 1995 산학협력기술연구논문집 Vol.1 No.-

The structure of the turbulent wall layer developing into flow separation was studied. The experiments were performed to find out the formation of turbulent separation lead to diverging of the diffuser wall in a two-dimensional asymmetric diffuser which was attached to a downstream end of a long straight channel to provide a fully-developed turbulent inlet condition. First report, this is to estimate how to develop the region of the separation in the smooth diffuser wall with diverging condition and then is the reference on the characteristics of rough diffuser wall being under discussion at second report. As a result, static pressure profile of the fixed wall are in accord with the static pressure profire of the movable wall. Separation has broken out at the diffuser open angle θ=7o, while the diffuser openingangle is increasing, the region of the separation is advanced at the upstream and separation appears at the diffuser open angle θ=12o in the fixed wall too.

발달장애아의 조기 치료교육의 필요성과 손동작을 중심으로 한 인지교육 프로그램

채경주,김신영 경복대학 2002 京福論叢 Vol.6 No.-

고도로 발달된 의학정보로 인하여 장애아들은 대부분 출생초기부터 장애의 정도와 진행양상에 대한 기초지식을 제공받게 된다. 더불어 부모들의 지적 수준 향상 및 경제력 향상은 장애아들의 치료교육에 대한 욕구를 높이게 하였고, 이러한 욕구는 점차적으로 지역사회에 있어서 장애인 복지시설의 증가현상을 낳게 되었다. 따라서 복지관 및 장애아들을 대상으로 치료하고 있는 치료기관에서는 장애아동에 대한 치료 프로그램이 절실히 요구되고 있는 실정이나 현 장애아동에 대한 치료교육프로그램은 체계화되지 못하고 그 연구마저도 미비한 실정이다. 이에 본 연구는 조기 치료교육의 필요성을 인식하고 복지기관을 비롯한 장애아동을 대상으로 치료하고 있는 기관들에서 실시하고 있는 조기 치료교육 프로그램에 대한 기본개념과 인지교육 프로그램에 있어서 손 동작을 이용한 치료적 접근에 관하여 알아보고자 한다. This is the research for the purpose of define necessity of therapeutic education for developmental disorders, setting up a program of cognitive education with hands movements. We hope that this program will promote quailty of therapeutic education with disabled children and will be useful to occupational therapist with cognitive therapeutic program for disabled children in clinic. Futhermore, we suggest the study of therapeutic education program be done as soon.

한국근대기 일본인 이주어촌내 가옥의 변용양상에 관한 연구 : 외나로도 축정 1ㆍ2구 일대의 1열형 가옥을 중심으로

강경남,박중신,김성중,김태영 대한건축학회 2005 대한건축학회논문집 Vol.21 No.2

This paper aims to clarify transformation of I-line type houses of Japanese migrant fishing vi11age in Oenaro-do Island. The basic type of I-line type house has rectangular spatial configuration simply composed of shop(entrance), room, and kitchen in plan, and eaves line & grid openings in facade. The existing openings are transformed into the aluminium 4 sliding door. In case of alterations and additions, the water closet and bath room alter the interior space of basic plan. The room, boiler, and storehouse are attached to I-line type house, and enlarged more them l-line-4-column in plan. In case of new-built constructions, the basic type of one-story building is same to 1-line-4-column type expanded from I-line type 3-column, the two stories houses with shop are mostly represented, and the other houses enlarge the lot and building scale. These new-built flat slab houses have balcony and bond beam considering eaves line of adjacent houses in facade.

RAW 264.7 세포에 대한 중국산 천연 광물성 섬유 TAFMAG의 독성효과

임영,한진구,김지홍,김현욱,김은경,김경아,장황신 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.3

Objectives : This study was designed to evaluate cytotoxicity of TAFMAG, which is a trade name of natural mineral fiber mined and produced in China. Methods : The cytotoxicity of TAFMAG was evaluated by measuring iron content, lipid peroxidation, erythrocyte hemolysis, and cytotoxicity in vitro. These results were compared with the data of chrystotile and wollastonite as a positive and negative control, respectively. Results : There was significant increase of Fenton activity in TAFMAG and chrysotile with dose-response pattern. The iron chelating agent, desferrioxamine, significantly decreased Fenton activity of the particulates except wollastonite. TAFMAG and chrysotile fibers significantly increased malondialdehyde concentration from lipid peroxidation of the red blood cell membrane. In erythrocyte hemolysis test, TAFMAG & chrysotile had stronger effect on erythrocyte hemolysis than wollastonite with the concentration of 1,000g/ml. Furthermore, TAFMAG was more hemolytic than chrysotile with the concentration of 5,000g/ml. There was a significant cytotoxic effect in TAFMAG and chrysotile on RAW cell compared with wollastonite. Conclusions : In vitro study suggested that TAFMAG may have a similar health hazard as usual asbestos.

赤何首鳥와 白何首鳥의 外部 및 內部形態

宋坰松,申喆均,朱榮丞 대한본초학회 2004 大韓本草學會誌 Vol.19 No.1

Objectives : This study was designed to establish a characteristic discrimination of internal and external morphological standard of original plants and herbal states in Polygoni Multiflori and Cynanchi Wilfordii Radix. Methods : In this studies, the external-internal morphological standards were determined by using stereoscope and butanol series. Results : 1. The external characteristics of original plants: Polygonum multiflorum has alternate leaves, and its flower with white color blooms at the shoot apex or leaf axil. In the other hand, Cymchum wilfor&i has opposite leaves, and its flower with yellowish green color blooms at the leaf axil. 2. The physical characteristics of herbal states: Polygoni Multiflori Radix is red-brown in outer surface, pink-brown in section. In the other hand, Cynanchi Wilfordii Radix is earthly-brown in outer surface, greyish white in section. 3. The physical characteristics according to the place of production: Demonstrable difference according to the place of production is not seen. Polygoni Multiflori Radix is brown or dark brown in outer surface, soft yellow-dark brown in section. In the other hand, Cynanchi Wilfordii Radix is white in outer surface, white-weak red in section, and has power type. 4. The internal characteristics: Pofygonum mulQt7orum has hetero-vascular bundle and lignification of cork layer is progressive. In the other hand, cynanchum wilfordii has not hetero-vascular bundle, and lignification of cork layer is weak. Conclusion : In the future, many fundamental study such as how to discriminate between Polygoni Multiflori Radix and Cynanchi Wilfordii Radix in origin and efficacy will be necessary. Also the standard of discrimination must be specific and distinct in that several kinds of fo-ti has been traded.

Coxiella burnetii에 대한 항체의 검출을 위한 Enzyme-Linked Immunosorbent Assay의 정립

이경호,박주영,박윤선,김수기,신운섭,고춘명 대한감염학회 1994 감염 Vol.26 No.4

본 연구에서는 지금까지 진단이 내려지지 않았던 C. burnetii 감염증 환자들을 보다 빠르고 간편하며 정확하면서도 대량으로 검사할 수 있는 방법으로서 C. burnetii 단백항원을 이용한 효소면역측정법을 정립하고자 하였다. 본 실험에서 정립한 효소면역측정법은 간접 방법으로서 C. burnetii phase I에 대한 IgG를 검출하기 위해 고안되었다. C. burnetii 단백질 항원의 적정 농도는 야성 대조혈청의 흡광도와 음성 대조혈청에서의 흡광도의 차이가 가장 크게 나는 농도인 1ug/ml을 적정항원농도로 결정하였으며, 검사 혈청의 적정희석 농도도 역시 양성대조항원의 OD 값과 음성대조항원에서의 OD값의 차이가 가장 크게 나면서 비교적 background activity가 적은 혈청의 희석 농도인 1:300을 적정 혈청 희석 농도로 결정하였다. 이 때 각각의 야성 혈청이 0.185의 흡광도를 가질 수 있는 가장 높은 혈청 희석 농도의 로그값과, 같은 혈청을 1:300으로 희석했을 때의 흡광도 사이에 상관계수 r값이 0.95인 직선적 관계가 성립하여, 하가지 혈청 희석 농도(1:300)에서 결정된 ELISA값이 그 혈청의 항체가를 양적으로 표시하였다. 효소면역측정법의 양성 판정 기준은, IFA에서 C. burnetii에 대한 항체가 음성으로 확인된 혈청 100개를 대상으로 ELISA를 시행하여, 이들의 흡광도의 산술평균치와 표준편차를 구한 결과, 신뢰구간 95%에서 최고치인 0.185를 ELISA 야성 판정의 기준인 cut-off value로 정하였다. 위애서 정한 기준에 의해 ELISA를 시행하엿을 때, IFA에서 양성으로 판명된 혈청 모두에서 양성으로 나타나 민감도가 매우 높은 것으로 나타났다. 다음으로 ELISA 방법의 특이도를 조사하기 위해서, IFA 검사에서 음성으로 확인된 혈청(혈청 희석 농도 1:10에서 음성)을 대상으로 ELISA를 시행한 결과, blocking agent로서 1% BSA를 사용했을 때는 9.3%, 5% NGS는 11.3%, 그리고 blocking을 전혀 하지 않았을 때는 15.3%의 위양성율을 나타내어, BSA와 NGS 상이에는 통계학적으로 차이가 없었으나, blocking을 하지 않는 것 보다는 하는 것이 위양성율이 적은 것으로 나타났다. 그러나, 이것은 어디까지나 IFA기준이며, 절대적인 의미에서의 위양성율을 의미하는 것은 아니다. 결론적으로 본 연구에서 정립한 효소면역측정법은 매우 높은 민감도를 갖고 있으므로 Q fever가 의심되는 환자를 screening하기 위한 적절한 방법으로 사료된다. Currently, the indirect immunofluorescence assay(IFA) is used for detecting antibodies to Coxiella burnetii. Although reliable, this method is time-consuming, and the results are subject to interpretation. To develop an alternative test, we used an enzyme-linked immunosorbent asssy (ELISA) because it was faster, less complicated, and more objective than the IFA. The ELISA, unlike the IFA, can also be automated. In this study an indirect ELISA using C. burnetii protein antigens was developed to detect immunoglobulin G to C. burnetii phase I. A linear relation was found between the logarithms of absorbance values of sera at a dilution of 1/300 and the titres as determined by an end point dilution ELISA. The finding of linear relation (r=0.95) confirmed that an ELISA value determined with a single serum dilution (1:300) can be interpreted quantitatively as the titer of antibody in that serum. A serum dilution of 1:300 was used in all subsequent tests because at this dilution the difference between absorbance values for positive and negative sera was greatest: a serum sample was regarded as positive if the OD? value was ≥0.185 (absorbance threshold) at this dilution. The results obtained by the ELISA were compared with those by the IFA established already. The results indicate that the assay provides a sensitive, alternative method for diagnosing Q fever, but it needs reevaluation for the specificity because of its high false-positive rates.