• Title/Summary/Keyword: 2면 접착

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A study on the distribution of latent fingerprints on paper knife sheaths (간이 칼집에서의 잠재지문 분포에 관한 연구)

  • Kim, Hyo-Mi;Park, Gi-Hyun;Lee, Su-Bhin;Yu, Je-Seol
    • Analytical Science and Technology
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    • v.34 no.6
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    • pp.251-258
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    • 2021
  • Knives are most frequently used as weapons in violent crimes. Criminals leave behind knife sheaths made of paper and tape at crime scenes. It is difficult to develop fingerprints using tape attached to a porous surface, resulting in the need to explore effective techniques for identifying fingerprints as well as the distribution of fingerprints on each surface, when evidence such as paper knife sheaths are found. In this study, 50 knife sheaths were prepared. The cyanoacrylate fuming (CA fuming) method was applied to develop fingerprints on the non-adhesive side of the tape, and a dual-purpose 1,2-indanedione/Zn (1,2-IND/Zn) reagent was used to separate tape from paper while simultaneously developing fingerprints on the paper. The fingerprints on the adhesive side of the tape were developed using Wet Powder Black®. Using the R statistical analysis program (The R Foundation for Statistical Computing), we used a heat map to indicate the location of fingerprints developed from each surface. More fingerprints were detected at the ends than in the center of the adhesive side of the tape, and although the non-adhesive sides of tape and paper did not present clear distribution patterns, many fingerprints were developed that had sufficient clarity for personal identification. The results of this study may be applicable for processing evidence when paper sheaths are found at crime scenes.

A Study on the Fabrication of the Laminated Wood Composed of Poplar and Larch (포푸라와 일본잎갈나무의 집성재 제조에 관한 연구)

  • Jo, Jae-Myeong;Kang, Sun-Goo;Kim, Ki-Hyeon;Chung, Byeong-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.25-31
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    • 1974
  • 1. Various gluing qualities applying Resorcinol Plyophen #6000 were studied on aiming the strength relationships of laminated woods resulted by single species [poplar (Populus deltoides), larch(Larix leptolepis)], mixed species of (poplar and larch), preservatives, treated poplar the scarf joint with mixed species of poplar and larch and the scarf joint treated with preservatives. 1. 1 On the block shear and on the DVL tension test, the mean wood failure ratio showed an excellent value i.e., above 65% and the tangential strength for larch was higher than that of radial, but it was reversed for poplar as shown in Tables 1 and 2. 1. 2 The lamina treated with Na-PCP reduced slightly the strength but the limited strength allowed for manufacturing laminated wood was not influenced by treating Na-PCP as shown in Tables 3 and 4. 1. 3 The safe scarf ratio in the plane scarf joint was above 1/12 for larch and 1/6 for poplar regard less of the chemical treatment or untreatment as shown in Tables. 5, 6, 7 and 8. 2. In the normal and boiled state, the gluing quality of the laminated wood composed of single[poplar (Populus deltoides), larch (Larix leptolepis)] and double species (poplar and larch) glued with Resorcinol Plyophen #6000 were measured as follow, and also represented the delamination of the same laminated wood. 2.1 The normal block shear strength of the straight and curved laminated wood (in life size) were more than three times of the standards adhesion strength. And, the value of the boiled stock was decreased to one half of the standard shear adhesion strength, but it was more than twice the standard strength for the boiled stock. Thus, it was recognized that the water resistance of the Resorcinol Plyophen #6000 was very high as shown in Tables 9 and 10. 2. 2 The delamination ratio of the straight and curved laminated woods in respect of their composition were decraesed, in turn, in the following order i. e., larch, mixed stock (larch+poplar) and poplar. The maximum value represented by the larch was 3.5% but it was below the limited value as shown in Table 11. 3. The various strengthes i.e., compressive, bending and adhesion obtainted by the straight laminaced wood which were constructed by five plies of single and double species of lamina i. e., larch (Larix leptolepis) and poplar (Populus euramericana), glued with urea resin were shown as follows: 3. 1 If desired a higher strength of architectural laminated wood composed of poplar (P) and larch (L), the combination of the laminas should be arranged as follows, L+P+L+P+L as shown in Table 12. 3.2 The strength of laminated wood composed of laminas which included pith and knots was conside rably decreased than that of clear lamina as shown Table 13. 3.3 The shear strength of the FPL block of the straight laminated wood constructed by the same species which were glued with urea adhesives was more than twice the limited adhesion strength, thus it makes possible to use it for interior constructional stock.

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THE EFFECTS OF SURFACE TREATMENT OF DENIAL NICKEL-CHROMIUM ALLOY ON TENSILE BOND STRENGTH (치과용 니켈-크롬합금에 대한 표면 처리가 인장접착강도에 미치는 영향)

  • Lee, Eun-Suk;Kwon, Oh-Won
    • The korean journal of orthodontics
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    • v.27 no.3 s.62
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    • pp.493-502
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    • 1997
  • This study was conducted to evaluate the tensile bond strength by bonding the dental bracket with Super-bond after treating the surface of dental Nickel-Chromium alloy with sandblasting, sandblasting & tin-plating, respectively, and tin-plating. 10 pieces of Nickel-Chromium alloys with brackets bonded with Super-bond without their surface treatment were sampled as a control group, 20 pieces of Nickel-Chromium alloy brackets bonded with Super-bond after treating them with sandblasting as group I, 20 pieces of Nickel-Chromium alloys tin-plated and bonded with Super-bond after sandblasting as group II, and then 20 pieces of alloys with brackets bonded with Super-bond after tin-plating as group III. The result of those examination and comparison is summarized as follows: 1. Group I showed the mean tensile bond strength of $14.41{\pm}2.24MPa$ which was highest among 4 groups, followed by group III($13.59{\pm}.51MPa$), group II($12.27{\pm}.45MPa$), and control group($10.50{\pm}1.57MPa$), respectively. However, it was shown that there was no statistically significant difference between group I and III, group III and II, and group II and control group(p>0.05). 2. The main failure pattern of those brackets showed that $70\%$ of the control group had an adhesive failure at the bracket-Superbond interface, and $30\%$ at the Nickel-Chromium alloy-Superbond interface, while other groups did the adhesive failure at the bracket-Superbond interface. 3. When examined under SEM, it was shown that adhesives were mostly attached to the surface of the Nickel-Chromium alloy for all groups while a considerable quantity of adhesives were attached to the bracket base. Then, those samples treated only with sandblasting showed the most even and remarkable roughness of their surface.

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BONDING OF RESIN INLAY TO GLASS-IONOMER BASE WITH VARIOUS TREATMENTS ON INLAY SURFACE (내표면 처리에 따른 레진 인레이와 글래스아이오노머 베이스간의 접착)

  • Jang, Byung-Sung;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.25 no.3
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    • pp.399-406
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    • 2000
  • The effect of inlay surface treatment on bonding was investigated when resin inlay was bonded to resin-modified glass-ionomer base with resin cement. For the preparation of glass-ionomer base, resin-modified glass-ionomer cement (Fuji II LC, GC Co., Japan) was filled in class I cavities of 7mm in diameter and 2mm in depth made in plastic molds. Eighty eight resin inlay specimens were made with Charisma$^{(R)}$ (Kulzer, Germany) and then randomly assigned to the four different surface treatment conditions: Group I, $50{\mu}m$ aluminium oxide sandblasting and silane treatment ; Group II, silane treatment alone ; Group III, sandblasting alone, and Group IV (control), no surface treatment. After a dentin bonding agent with primer (One-Step$^{TM}$, Bisco Inc., IL., U.S.A.) was applied to bonding surface of resin inlay and base, resin inlay were cemented to glass-ionomer base with a resin cement (Choice$^{TM}$, Bisco Inc., IL., U.S.A.). Shear bond strengths of each specimens were measured using Instron universal testing machine (4202 Instron, lnstron Co., U.S.A.) and fractured surfaces were examined under the stereoscope. Statistical analysis was done with one-way ANOVA and Dunkan's multiple range test. The results were as follows: 1. Sandblasting and silane treatment provided the greatest bond strength(10.56${\pm}$1.95 MPa), and showed a significantly greater bond strength than sandblasting alone or no treatment (p<0.05). 2. Silane treatment provided a significantly greater bond strength(9.77${\pm}$2.04 MPa) than sandblasting alone or no treatment (p<0.05). However, there was no significant difference in bond strength between sandblasting treatment and silane one (p>0.05). 3. Sandblasting alone provided no significant difference in bond strength from no treatment (p>0.05). 4. Stereoscopic examination of fractured surface showed that sandblasting and silane treatment or silane treatment alone had more cohesive failure mode than adhesive failure mode. 5. In relationship between shear bond strength and failure mode, cohesive failure occurred more frequently as bond strength increased.

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The Effect of Bonding Resin on Bond Strength of Dual-Cure Resin Cements (접착레진의 부가도포가 레진 시멘트의 결합강도에 미치는 영향에 대한 연구)

  • Kim, Duck-Su;Park, Sang-Hyuk;Choi, Gi-Woon;Choi, Kyung-Kyu
    • Restorative Dentistry and Endodontics
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    • v.32 no.5
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    • pp.426-436
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    • 2007
  • The objective of this study is to evaluate the effect of an additional application of bonding resin on the bond strength of resin luting cements in both the light-cure (LC) and self-cure (SC) modes by means of the ${\mu}TBS$ tests. Three combinations of One-Step Plus with Choice, Single Bond with Rely X ARC, and One-Up Bond F with Bistite II were used. D/E resin and Pre-Bond resin were used for the additional application. Twelve experimental groups were made. Three mandibular $3^{rd}$ molars were used in each group. Indirect composite blocks were cemented on the tooth surface. $1\;{\times}\;1\;mm^2$ dentin-composite beam for ${\mu}TBS$ testing were made and tested. When total-etching dentin adhesives were used, an additional application of the bonding resin increased the bond strength (P < 0.05). However, this additional application didn't influence the bond strength of self-etching dentin adhesives (P > 0.05). In conclusion, the results suggest that an additional application of the bonding resin increases bond strength and enhances quality of bonding when using total-etching dentin adhesives.

Comparative evaluation of micro-shear bond strength between two different luting methods of resin cement to dentin (합착 술식에 따른 레진 합착제의 상아질에 대한 미세전단결합강도의 비교 연구)

  • Lee, Yoon-Jeong;Park, Sang-Jin;Choi, Kyoung-Kyu
    • Restorative Dentistry and Endodontics
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    • v.30 no.4
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    • pp.283-293
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    • 2005
  • The purpose of this study was to evaluate the effect of dual bonding technique by comparing microshear bond strength between two different luting methods of resin cement to tooth dentin. Three dentin bonding systems(All-Bond 2, One-Step, Clearfil SE Bond), two temporary cements (Propac, Freegenol) were used in this study. In groups used conventional luting procedure, dentin surfaces were left untreated. In groups used dual bonding technique, three dentin bonding systems were applied to each dentin surface. All specimens were covered with each temporary cement. The temporary cements were removed and each group was treated using one of three different dentin bonding system. A resin cement was applied to the glass cylinder surface and the cylinder was bonded to the dentin surface. Then, micro-shear bond strength test was performed. For the evaluation of the morphology at the resin/dentin interface, SEM examination was also performed. 1. Conventional luting procedure showed higher micro-shear bond strengths than dual boning technique. However, there were no significant differences. 2. Freegenol showed higher micro-shear bond strengths than Propac, but there were no significant differences. 3. In groups used dual bonding technique, SE Bond showed significantly higher micro-shear bond strengths in One-Step and All-Bond 2 (p<0.05), but there was no significant difference between One-Step and All-Bond 2. 4. In SEM observation, with the use of All-Bond 2 and One-Step, very long and numerous resin tags were observed. This study suggests that there were no findings that the dual bonding technique would be better than the conventional luting procedure.

EFFECT OF FILM THICKNESS OF RESIN CEMENT ON BONDING EFFICIENCY IN INDIRECT COMPOSITE RESTORATION (레진 시멘트의 film thickness가 간접 복합 레진 수복물의 접착 효율에 미치는 영향에 관한 연구)

  • Lee, Sang-Hyuck;Choi, Gi-Woon;Choi, Kyung-Kyu
    • Restorative Dentistry and Endodontics
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    • v.35 no.2
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    • pp.69-79
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    • 2010
  • The purpose of this study was to evaluate the effect of film thickness of various resin cements on bonding efficiency in indirect composite restoration by measurement of microtensile bond strength, polymerization shrinkage, flexural strength and modulus, fractographic FE-SEM analysis. Experimental groups were divided according to film thickness (< $50\;{\mu}m$-control, $50\;{\mu}m$-T50, $100\;{\mu}m$-T100, $150\;{\mu}m$-T150) using composite- based resin cements (Variolink II, Duo-Link) and adhesive-based resin cements (Panavia F, Rely X Unicem). The data was analyzed using ANOVA and Duncan's multiple comparison test (p < 0.05). The results were as follows ; 1. Variolink II showed higher microtensile bond strength than that of adhesive-based resin cements in all film thickness (p < 0.05) but Duo-Link did not show significant difference except control group (p > 0.05). 2. Microtensile bond strength of composite-based resin cements were decreased significantly according to increasing film thickness (p < 0.05) but adhesive-based resin cements did not show significant difference among film thickness (p > 0.05). 3. Panavia F showed significantly lower polymerization shrinkage than other resin cements (p < 0.05). 4. Composite-based resin cements showed significantly higher flexural strength and modulus than adhesive-based resin cements (p < 0.05). 5. FE-SEM examination showed uniform adhesive layer and well developed resin tags in composite-based resin cements but unclear adhesive layer and poorly developed resin tags in adhesive-based resin cements. In debonded surface examination, composite-based resin cements showed mixed failures but adhesive-based resin cements showed adhesive failures.

BOND STRENGTH OF BONDED AMALGAM USING DENIAL ADHESIVES (치과용 접착제를 사용한 접착 아말감의 결합 강도)

  • Kam, Dong-Hoon;Lee, Sang-Dae;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.2
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    • pp.284-295
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    • 1999
  • The purpose of this study was to measure and analyze the bond strength of bonded amalgam using dental adhesives and to compare this with light-curing composite resin. Sections 8mm in diameter were punched out from the labial surface of bovine anterior teeth. These were embedded in clear acrylic resin blocks with labial surface facing out. 55 specimens were made for enamel and dentin each. After dividing these into 5 groups, group 1: Superbond C&B, group 2: Panavia 21, group 3: All-Bond 2, group 4: Fuji I Glass Ionomer Luting Cement, group 5: Scotchbond Multi-Purpose(Restorative Z-100), molds with holes of 6.3mm in diameter and 1.5mm in depth were placed over the specimens. The exposed tooth surfaces were treated with adhesives and the molds were filled with amalgam. In group 5, the mold was filled with composite resin and light-cured for 40 seconds. The author measured all specimens for bond strength 24 hours after amalgam filing and analyzed fracture surfaces. The following results were obtained: 1. Among the dentin groups, groups 1, 2 and 4 showed significantly lower bond strength compared with group 5(P<0.05). 2. Among the enamel groups, group 4 showed significantly lower bond strength compared with group 5(P<0.05). 3. In group 2, 2D showed significantly lower bond strength compared with group 2E(P<0.05). Other adhesives showed no such differences in bond strength between dentin and enamel(P>0.05). 4. Cohesive failure was observed in groups 1E and 5D, while mixed failure was seen in groups 1 and 5. Only adhesive failures were noted in groups 2, 3, 4.

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EFFECTS OF COLLAGENASE AND ESTERASE ON DENTIN BOND STRENGTH AND NANOLEAKAGE (Collagenase와 esterase가 상아질 접착강도와 nanoleakage에 미치는 영향)

  • Jung, Young-Jung;Hahn, Se-Hyun;Kim, Chong-Chul;Lee, Sang-Hoon;Kim, Jung-Wook;Kim, Young-Jae;Jang, Ki-Taeg
    • Journal of the korean academy of Pediatric Dentistry
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    • v.35 no.3
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    • pp.389-398
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    • 2008
  • The purpose of this study was to evaluate the effects of collagenase and esterase on dentin bond strength and nanoleakage. Resin composites were bonded to occlusal dentin of premolars with Single Bond 2(SB) and Clearfil SE Bond(SE). After the microtensile specimens were prepared and stored in PBS for 24 hours(I) or, PBS(II), collagenase(III), esterase(IV) solution for 4 weeks, the specimens were stained with silver nitrate solution. Microtensile bond strength(${\mu}TBS$) and silver penetration area were measured and, the results were as follows: 1. For group II, III, and IV, the bond strengths of SB were lower than those of SB(p<0.05). The bond strengths of SB II, III, and IV were lower than that of SB I(p<0.05). There was no difference among the bond strengths of SE $I{\sim}IV$ groups(p>0.05). 2. Silver penetration areas of SB were higher than those of SE for all storage groups(p<0.05). In SB and SE groups, there was no significant difference of silver penetration area among $I{\sim}IV$ groups(p>0.05). 3. SE I, II, and III showed inverse relationship between the bond strengths and the silver penetration areas(p<0.05).

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Compressive and Adhesive Strengths of Mortars using Re-emulsification Type Polymer and Ultra-Rapid-Hardening Cement (재유화형 분말수지와 초속경 시멘트를 혼입한 모르타르의 압축강도 및 접착강도 특성)

  • Lee, Kwang-Il;Yoon, Hyun-Sub;Yang, Keun-Hyeok
    • Journal of the Korea Institute of Building Construction
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    • v.18 no.4
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    • pp.329-335
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    • 2018
  • The objective of this study is to develop a mortar mixture with high workability and adhesive strength for section jacketing in seismic strengthening technology of existing concrete structures. To achieve targeted requirements of the mortars (initial flow exceeding 200 mm, compressive strength of 30MPa, and adhesive strength exceeding 1MPa), step-by-step tests were conducted under the variation of the following mixture parameters: water-to-binder ratio, sand-to-binder ratio, polymer-to-binder ratio, dosage of viscosity agent, and content of ultra-rapid-hardening cement. The adhesive strength of the mortars was also estimated with respect to the various surface treatment states of existing concrete. Based on the test results, the mortar mixture with the polymer-to-binder ratio of 10% and the content of ultra-rapid-hardening cement of 5% can be recommended for the section jacketing materials. The recommended mortar mixture satisfied the targeted requirements as follows: initial flow of 220 mm, high-early strength gain, 28-day compressive strength of 35MPa, and adhesive strength exceeding 1.2MPa.