http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Nanofilled 복합레진으로 와동 충전 시 flowable 레진 사용 유무에 따른 피로시험 후의 미세 변연 누출 비교
한선덕,김원,최지영,오남식,이명현,Han, Sun-Deok,Kim, Won,Choi, Ji-Young,Oh, Nam-Sik,Lee, Myung-Hyun 대한치과보철학회 2009 대한치과보철학회지 Vol.47 No.3
Statement of problem: when using resin for class II restoration, micoleakage by instrumentation can be regarded as the primary negative characteristic. A review of the available literature suggests that using flowable resin as liner to decreased microleakage. Purpose: The aim of this study was to determine the influence of the nanofilled flowable resin lining on marginal microleakage after load cycling in class II composite restoration fillings using nanofiller resin. Material and methods: 24 extracted premolars were prepared with class II cavity. F group was restored the nanofilled resin with the nanofilled flowable resin as liner. NF group was restored the nanofilled resin only. After restoration, an experiment was performed on 2 groups using a 300N load at 104, 105 and 106 cycles. Prior to and before each load cycling, it was gauged length on total marginal microleakage, axial marginal microleakage and buccal, gingival, lingual marginal microleakage. Data were analyzed with the Mann-Whitney test & Kruskal-Wallis test. Results: There were statistically significant differences between 2 groups and between individual groups. (P <.05) The result showed less microleakage in teeth restored by the nanofilled resin, which was lined by the nanofilled flowable resin. Conclusion: There was significant reduction in microleakage when the nanofilled flowable resin lining was placed underneath the nanofilled resin in class II composite restoration fillings. 연구 목적: 제2급 와동에서 nanofilled 레진 충전 시 기구 조작 방향에 따라 변연 누출 가능성이 있다. 따라서 기구 조작에 따른 변연 누출을 줄이고자 인접면변연에 flowable 레진의 사용 유무에 따라 반복 하중 전후에 미세 변연 누출의 차이를 보고자 하였다. 연구 재료 및 방법: 건전한 상태의 24개의 발치 된 치아를 제2급 와동으로 형성한 뒤 그룹F는 nanofilled 레진으로 충전 시 flowable 레진을 liner로 사용하였고, 그룹 NF는 nanofilled 레진으로만 충전 하였다. 300N의 하중으로 $10^4$, $10^5$, $10^6$번의 반복하중을 가했다. 반복하중 전후로 모든 시편에서 전체 미세 변연 누출 길이 (T), 축면 미세 변연 누출 길이 (A), 치은 미세 변연 누출 길이 (G), 협측 미세 변연 누출 길이 (B), 설측 미세 변연 누출 길이 (L)를 측정하여, 각변연누출비율을 비교하였다. 통계는 Mann-Whitney test와 Wilcoxon signed ranks test로 하였다. 결과: 하중 전에 그룹F의 전체 미세 변연 누출 백분율은 0.6%이고 그룹 NF는 5.6%이며, 하중 후에는 그룹 F는 13.0%이고 그룹 NF는 36.3%로 그룹 NF에서 미세 변연 누출이 컸고, 반복 하중 횟수가 증가할수록 더욱 커졌으며, 부위상으로는 치은 변연의 미세 변연 누출이 컸다. 통계적 분석 결과 그룹NF의반복횟수별 하중 전후 비교에서 경계성으로 유의한 차이를 보였다. 결론: 제2급 와동에서 nanofilled 레진 충전 시 인접면 변연에 flowable 레진을 liner로 사용할 경우 반복 하중 전후에 미세 변연 누출의 감소에 영향을 주었다. 그리고 liner로 사용된 flowable 레진은 300 N의 반복 하중에서도 견딜 수 있었다.
Shade Flask 법을 이용한 1-Octanol/Water 분배계수 측정
한선덕(Seon Deok Han),박수진(Soo Jin Park),박소진(So Jin Park) 한국화학공학회 1997 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.35 No.1
The 1-octanol/water partition coefficient(K_(ow)) is used to estimate the chemical`s fate and the behavior of chemicals against the organization. We want to determine the K_(ow) by using shake flask(SF) method. Firstly we established the requiring time for preparing of saturated solution and for partitioning equilibrium in the SF method with tert-butanol. The accuracy and reproducibility of this SF method was reliable since the average deviation was less than 5 % between measured K_(ow) values of alcohols(C₁-C_7) and the reported values. The K_(ow) for some chlorinated and aromatic compounds were measured. The K_(ow) of these organic chemicals were linearly proportional to their molar volumes and the relationship of K_(ow) and water solubilities can be expressed by a first order linear equation.
Headspace gas chromatography를 이용한 n-Heptane 혼합계의 기액평형과 무한 희석 활동도계수
백승관,한선덕,박소진,오종혁,류선아 忠南大學校 産業技術硏究所 1996 산업기술연구논문집 Vol.11 No.2
Pure n-heptane is used as a standard for octane rating determinations and n-heptane mixtures with alcohols are commonly used as a model for developing of thermodynamic models. The vapor-liquid equilibria of (C₂∼C₄)alcohol+n-heptane are measured at 60℃. All the measured vapor-liquid equilibrium(VLE) data have had minimum boiling azeotropes, and the azeotropes are moved into n-heptane rich rigion with increasing the carbon number of alcohols. The measured VLE data of each binary systems are good correlated with Wilson and NRTL models. Infinitely dilute activity coefficients are calculated for each binary systems by second order extrapolation method from the measured VLE data.
EPICS 법을 이용한 Air / Water 분배계수 ( Henry 상수 ) 측정과 포화증기압 및 포화용해도와의 상관관계
박소진(So Jin Park),한선덕(Seon Deok Han),류선아(Seon Ah Ryu) 한국화학공학회 1997 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.35 No.6
Air/water partition coefficients(K_(aw)) as environmental parameter were measured by EPICS(equilibrium partitioning in closed system) method. K_(aw) of some n-alkanes were measured to test EPICS method. The accuracy and reproducibility of this method were reliable, since experimental values were agreed very well with literature values. Then, we measured K_(aw) and Henry`s law constants of some organic compounds which are widely used in the field of chemical industry and MTBE and TAME which are recently used as an octane booster for unleaded or low leaded gasoline. The relationship between K_(aw) and vapor pressure and water solubility was analysed. The measured K_(aw) was linearly proportional to molar volume and temperature, and inversely proportional to water solubility and vapor pressure except substituted benzene. Henry`s constants are increased with the temperature.