http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
치과용 지르코니아 표면 특성이 레진시멘트와의 결합강도에 주는 영향
나종찬,허수복,최재윤,이상훈,양형철,임범순 大韓齒科器材學會 2010 대한치과재료학회지 Vol.37 No.1
The purpose of this study was to evaluate the influence of surface characteristics and different resin cements on the shear bond strength of dental zirconia ceramics. Three zirconia ceramics (Cercon Base, Lava, ZirAce) were tested. The specimens were equally divided into four groups according to the surface treatment (mirror polished, CTL; ground with #80 diamond wheels, GD; sandblasted, SD; Rocatec treated, RC). After surface treatment, surface roughness, contact angle, and shear bond strength with four resin cements (Single bond, SB; Panavia F 2.0, PF; Clearfil SE Bond, CE; Superbond C&B, SU) were measured. Surface treatments did not cause significant differences in surface roughness (p>0.05). There was no significant different in contact angle between CTL and GD group (p>0.05), however, contact angles were significantly decreased in SD and RC groups. The total surface energy of GD and SD groups was significantly increased. RC group showed the highest surface energy and there were no significant differences in zirconia ceramics. The shear bond strength was significantly increased in SB, PF and CE resin cement groups after surface treatments (p<0.05). SD and RC groups showed higher shear bond strength than CTL. In SU groups, CTL showed the highest shear bond strength, there were not significantly differences with surface treatments in shear bond strength (p>0.05). There were very low correlations between surface roughness of zirconia and shear bond strength. Correlations between contact angle of zirconia and shear bond strength were different with application of different resin cement. Correlation was high in the order of SU, CE, SB and PF resin cements
나종찬(Jong Chan Na),김한기(Han Ki Kim),김찬수(Chan Soo Kim),한문희(Moon Hee Han) 大韓環境工學會 2014 대한환경공학회지 Vol.36 No.9
최근 해수와 담수의 염분농도차를 이용하여 발전하는 역전기투석(reverse electrodialysis, RED)은 잠재량이 크고 지속적 전력생산이 가능한 친환경적이며 미래지향적 신재생에너지로 인식되어 연구가 활발히 진행되고 있다. 이러한 RED 기술의 상용화를 위해서는 최적화된 운전조건을 찾는 것이 중요하며 특히, 스택 내부의 저항을 최소화하는 연구가 절실한 상황이다. 본 연구에서는 RED의 중요한 운전조건인 해수와 담수의 공급유량이 내부저항에 미치는 영향을 조사하고, 해수와 담수의 유량비에 따른 내부저항과 전력밀도의 관계를 고찰하여 최적의 운전조건을 실험적으로 파악하였다. 그 결과 전체유량 80mL/min에서 최적의 해수/담수 유량비는 1.7이었으며, 이때 전력밀도는 1.30 W/m2을 얻을 수 있었다. Reverse electrodialysis (RED) is a technique to produce electricity from two feed water that has different salinity. Recently, RED has been considered the attractive technology because this new process has large global potential and possibility to generate energy from abundant but largely unused resources. To make RED an economically attractive technology, the optimization of operation condition should be developed. In this study, we investigate the relation of internal resistance to power density of RED. And the effect of sea water and fresh water flow rate on power density was confirmed. To minimize the internal resistance and to increase power density of RED, the ratio of sea water and fresh water flow rate was optimized. Experimental result show the best performance with 1.30 W/m2 of power density at 1.7 flow ratio of seawater/freshwater.
나종찬,이용근,임범순,김철위 대한치과기재학회 2000 대한치과재료학회지 Vol.27 No.1
When using posterior composite resins, wear resistance is still a problem. Recently condensable composite resins which have proper condensability like dental amalgam and increased wear resistance have been introduced. The purpose of this study was to compare the wear resistance of newly developed condensable composite resins with those of universal composite resins by measuring the amount of wear and frictional force with a friction tester (Friction Player, FPR-2000, Rhesca, Japan). Two condensable composite resins (Surefil; Dentsply, Synergy Compact; Coltene) and two universal composite resins (Z100; 3M, Spectrum; Dentsply) were studied. The surface of 3 min(D)×8 mm(L) specimens was polished with wet 600 grit SiC paper. The specimens of non-aging group were stored in 37 ℃, 75 % ethanol for 7 days. After fixing SiC paper on the turn table of friction tester, 500 g load was applied to the specimen. With the linear velocity of 0.1257 cm/sec, the wear procedure was done for 10 minutes in distilled water, which resulted in 1.27 m wear distance. Amount of wear was measured by microscopic measuring device of a micro hardness tester (Shimadzu, Japan) in 0.1㎛ scale, and friction force was calculated from the frictional force-time graph. Regardless of the aging, there was no significant difference in wear resistance between condensable composite resins and universal composite resins (p>0.05). In every test groups, there was some variation in frictional forces initially, however there was no significant change depending on time (p>0.05). There was a weak correlation between wear amounts and frictional force.
석회화 낭성 치성종양과 법랑모세포 섬유치아종이 혼합된 치성종양
김형수,최승현,나종찬,안미영,이준,윤정훈 대한구강악안면병리학회 2015 대한구강악안면병리학회지 Vol.39 No.2
Calcifying cystic odontogenic tumor (CCOT), also known as calcifying odontogenic cyst or Gorin cyst is a rare developmental lesion which arises from odontogenic epithelium. It has been classified as a benign odontogenic neoplasm related to odontogenic apparatus by the World Health Organization. CCOT may be associated with other odontogenic tumors, most frequently odontoma, a finding that is a rare event in other types of odontogenic cysts or tumors. This report describes a case of hybrid odontogenic tumor composed of CCOT and ameloblastic fibroma-odontoma of the impacted right maxillary canine region that occurred in a 14-year-old female.
유태훈,최승현,나종찬,안미영,이준,윤정훈 대한구강악안면병리학회 2015 대한구강악안면병리학회지 Vol.39 No.1
Peripheral ameloblastoma, a rare and unusual variant of odontogenic tumor, representing 1% of all ameloblastomas. The extraosseous location is the peculiar feature of this type of tumor, which is otherwise similar to the classical ameloblastoma. This paper describes a case of peripheral ameloblastoma in a 43-year-old female affecting the left retromolar pad area of the mandible which was clinically diagnosed as a pyogenic granuloma. Histologically, the tumor showed of follicular ameloblastoma in continuity with a surface oral epithelium.
유태훈,최승현,나종찬,안미영,이준,윤정훈 대한구강악안면병리학회 2015 대한구강악안면병리학회지 Vol.39 No.1
Peripheral ameloblastoma, a rare and unusual variant of odontogenic tumor, representing 1% of all ameloblastomas. The extraosseouslocation is the peculiar feature of this type of tumor, which is otherwise similar to the classical ameloblastoma. This paper describesa case of peripheral ameloblastoma in a 43-year-old female affecting the left retromolar pad area of the mandible which was clinicallydiagnosed as a pyogenic granuloma. Histologically, the tumor showed of follicular ameloblastoma in continuity with a surface oralepithelium.