• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.369-370
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• 2007

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.171-172
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• 2007

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 추계학술발표회
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• pp.233-234
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• 2005

• 치위생과학회지
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• 제8권3호
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• pp.109-115
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• 2008

치과용 가시광선 중합형 복합수지의 광중합효율을 높이기 위해 2종의 새로운 액체형 amine 개시제인 MA, MPT와 현재 가장 많이 사용되고 있는 개시제인 AEM을 CQ, PD, DA에 각각 첨가하고 UDMA의 광중합효율을 알아본 결과 다음과 같은 결론을 얻었다. 1. 조사시간이 증가됨에 따라 amine 개시제의 종류에 관계없이 광중합효율이 점차 증가되었으며, 약 60초까지 조사였을 때에는 광중합효율이 급격히 증가되었으나 그 이상 조사하여도 광중합효율이 크게 증가되지 않았다. 2. AEM, MA와 MPT를 사용하였을 경우 모두 CQ > PD > DA의 순으로 광중합효율이 우수하게 나타났으나 AEM을 사용하였을 때 PD와 CQ는 큰 차이를 보이지 않았다. 3. CQ의 광중합효율은 새로운 광개시제인 MA와 MPT를 사용하였을 때가 범용으로 사용되고 있는 amine 개시제인 AEM을 사용하였을 경우보다 중합효율이 증가하는 결과를 보였다. 4. PD의 광중합효율은 MA와 함께 사용하였을 경우가 가장 높게 나타났으나 AEM의 경우와 큰 차이를 보이지는 않았다. 5. 이상의 결과로부터 MA와 CQ 및 PD를 함께 사용한 새로운 광중합시스템이 광중합효율을 높이는데 효율적인 것을 알 수 있었다.

• The Journal of Advanced Prosthodontics
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• 제9권2호
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• pp.77-84
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• 2017

PURPOSE. The aim of this study was to compare the surface roughness of zirconia when using Zircos E etching system (ZSAT), applying a nitric acid-hydrofluoric acid compound as a pretreatment agent, and also to compare the shear bonding strength according to different resin cements. MATERIALS AND METHODS. ZSAT, air abrasion, and tribochemical silicacoating were applied on prepared 120 zirconia specimens (10 mm in diameter, 7 mm in height) using CAD/CAM. Each 12 specimens with 4 different resin cements (Panavia F 2.0, Rely X Unicem, Superbond C&B, and Hot bond) were applied to test interfacial bond strength. The statistical analysis was performed using SAS 9.1 (SAS Institute Inc., Cary, NC, USA). The results are as follows: after application of the ZSAT on the zirconia specimens, surface roughness value after 2-hour etching was higher than those after 1- and 3-hour etching on SEM images. RESULTS. For Superbond C&B and Rely X Unicem, the specimens treated with ZSAT showed higher shear bond strength values than those treated with air abrasion and tribochemical silicacoating system. Regarding the failure mode of interface over cement and zirconia surface, Rely X Unicem and Hot bond showed cohesive failures and Panavia F 2.0 and Superbond C&B showed mixed failures. CONCLUSION. Zircos E etching system in zirconia restoration could increase its shear bond strength. However, its long term success rate and clinical application should be further evaluated.

• 한국자동차공학회논문집
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• 제22권6호
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• pp.9-13
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• 2014

Glass fiber reinforced thermoplastics(GFRTP) is made by adding chemical additive to glass fabric which is strong at a high temperate, incorrodible, and good at intensity and specific gravity. Although we focused on the weight lightening, the intensity of GFRTP is also important. To remedy thermoplastic resin's inferior property of matter to thermo-hardening resin, we formed several specimen, differing the chemical additive as Homo PP, MAPP 3%, Rubber 5%, and mixed. We put pressure of 5 type on the specimens. The analyses result for the different pressure, the resin spreads evenly, then the coherence is increased. Eventually, the mechanical properties are changed. When high intensity is needed, it is good idea to use polypropylene(PP) which has good coherence with glass fabric as chemical additive. We can get better intensity when we form the resin at the optimum pressure depending on mixing of chemical additive and glass fabric than when we increase the pressure.

• The Journal of Advanced Prosthodontics
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• 제3권1호
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• pp.16-19
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• 2011

PURPOSE. Purpose of this study was to evaluate effect of two surface treatments, sandblasting and monomer treatment, on tensile bond strength between two long term resilient liners and poly (methyl methacrylate) denture base resin. MATERIALS AND METHODS. Two resilient liners Super-Soft and Molloplast-B were selected. Sixty acrylic resin (Trevalon) specimens with cross sectional area of $10{\times}10$ mm were prepared and divided into two groups of 30 specimens each. Each group was surface treated (n = 10) by sandblasting (250 ${\mu}$ alumina particles), monomer treatment (for 180 sec) and control (no surface treatment). Resilient liners were processed between 2 poly(methyl methacrylate) surfaces, in the dimensions of $10{\times}10{\times}3$ mm. Tensile strength was determined with Instron Universal testing machine, at a crosshead speed of 5 mm/min; and the modes of failure (adhesive, cohesive or mixed) were recorded. The data were analyzed using one-way ANOVA, followed by Tukey HSD test (${\alpha}$= 0.05). RESULTS. Monomer pretreatment of acrylic resin produced significantly higher bond strengths when compared to sandblasting and control for both resilient liners (P < .001). Sandblasting significantly decreased the bond strength for both the liners when compared to monomer pretreatment and control (P < .001). Mean bond strength of Super-Soft lined specimens was significantly higher than Molloplast-B in various surface treatment groups (P < .05). CONCLUSION. Surface pretreatment of the acrylic resin with monomer prior to resilient liner application is an effective method to increase bond strength between the base and soft liner. Sandblasting, on the contrary, is not recommended as it weakens the bond between the two.

• 구강회복응용과학지
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• 제23권3호
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• pp.259-268
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• 2007

purpose: This study was to evaluate the shear bond strength of Lithium Disilicate Glass-Ceramic by removable method of temporary cement on the abutment tooth. Material and Method: Sixty molar teeth of human with the occlusal surface up were mounted in acrylic resin blocks. The 45 specimens were prepared to exposure dentin by diamond bur and the eugenol-containing temporary cement($Cavitec^{TM}$ ($KERR^{(R)}$, U.S.A)was applied to the dentin surfaces. After initial removal of the cement with a dental explorer, the specimens were divided into 4 groups of 15 specimens each. The dentin surfaces of the specimens were treated by rotary instrument with as follow pastes: $Zircate^{(R)}$ prophy paste(Dentsply, U.S.A), Radent Prophy Paste(Pascal company,inc. U.S.A), and Dental pumice(Wip mix corporation,U.S.A). An adhesive resin luting agent(Variolink $II^{(R)}$, Ivoclar Vivadent, Leichtenstein) including Monobond-S and $Excite^{(R)}$ was applied to all specimens. The ceramic specimens were made with an A1 ingot of IPS Empress $II^{(R)}$ (Ivoclar Vivadent, Leichtenstein). After the specimens were stored in distilled water for 48hr, the shear bond strength(MPa) was measured by a Universal testing machine(Zwick 145641, Zwick, Germany) at a 1mm/min cross-head speed. The data were statistically analyzed by one-way ANOVA and Duncan's multiple range test. Results: In all group, there were no significant differences in comparison with the control group(p>0.05). The pattern of most failure showed the mixed type of cohesive and adhesive failure. Conclusion: Resin bond strength of IPS Empress $II^{(R)}$ was not affected by removal method of the temporary cement.

• 공업화학
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• 제1권2호
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• pp.232-239
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• 1990

${\gamma}$-Glycidoxy propyl trimethoxy slilane, CTBN rubber (carboxyl terminated butadiene acrylonitrile rubber), GMA(glycidyl methacrylate) 등을 TEA(triethylamine) 및 BPO(benzoyl peroxide) 존재하에 결정성 실리카의 표면에 단계적으로 반응시켜 2.5~5.8%(중량%)의 피복율을 가진 표면처리 실리카를 제조하였다. 이것을 전체혼합물 중 0~60%(중량%)가 되도록 에폭시 수지 및 MTHPA (methyltetrahydrophthalic anhydride)와 혼합한 후 경화시켜 굴곡특성 및 열적특성을 시험하였다. 시험결과, 충전재 함량 35~55%(중량%)에서, 실란/고무 또는 실란/고무/비닐로 처리된 실리카를 충전한 것은 에폭시 수지에 고무를 직접 3% 혼합하고 여기에 표면 처리하지 않은 실리카를 충전한 것에 비하여 굴곡강도와 Tg는 각각 평균 25%, 13% 높은 값을, 굴곡탄성율은 5% 낮은 값을 나타내었다.

• 한국식품과학회지
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• 제27권3호
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• pp.313-317
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• 1995

대두침출액으로부터 대두올리고당을 생산하기 위하여 한외여과한 대두침출액의 정제를 목적으로 이온교환공정을 검토하였다. 차단분자량 20,000인 막을 사용하여 한외여과한 대두침출액을 이온교환처리할 경우 회분은 양이온교환수지에 의하여 대부분 제거되었으며 단백질 및 색소제거에는 음이온교환수지의 효과가 높았다. 회분 및 단백질 제거효과가 높은 수지는 각각 양이온교환수지 SK1B 및 음이온교환수지 WA30이었다. 이온교환시 ERR이 낮을 경우 단백질과 회분의 제거는 효과적이었으나 상당량의 올리고당이 수지에 흡착되어 소실되었다. 차단분자량 20,000인 막을 사용하여 한외여과한 대두침출액을 차단분자량 5,000인 막으로 2차 한외여과하여 단백질을 추가로 제거하고 혼합수지를 사용하여 ERR 5.0으로 이온교환처리한 결과, 단백질, 회분, 색소가 거의 전량 제거되었고 올리고당의 회수율도 높아 적정 이온 교환조건으로 결정되었다.