• The Journal of Korean Academy of Prosthodontics
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• v.58 no.3
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• pp.177-184
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• 2020

Purpose: The purpose of this study was to compare and evaluate the tensile bond strength of chairside reline resin to denture base resin fabricated by different methods (subtractive manufacturing, additive manufacturing, and conventional heat-curing). Materials and methods: Denture base specimens were fabricated as cuboid specimens with a width of 25 mm × length 25 mm × height 3 mm by subtractive manufacturing (VITA VIONIC BASE), additive manufacturing (NextDent Base) and conventional heat-curing (Lucitone 199). After storing the specimens in distilled water at 37℃ for 30 days and drying them, they were relined with polyethyl methacrylate (PEMA) chairside reline resin (REBASE II Normal). The subtractive and additive manufacturing groups were set as the experimental group, and the heat-curing group was set as the control group. Ten specimens were prepared for each group. After storing all bound specimens in distilled water at 37℃ for 24 hours, the tensile bond strength between denture bases and chairside reline resin was measured by a universal testing machine at a crosshead speed of 10 mm/min. The fracture pattern of each specimen was analyzed and classified into adhesive failure, cohesive failure, and mixed failure. Tensile bond strength, according to the fabrication method, was analyzed by 1-way ANOVA and Bonferroni's method (α=.05). Results: Mean tensile bond strength of the heat-curing group (2.45 ± 0.39 MPa) and subtractive manufacturing group (2.33 ± 0.39 MPa) had no significant difference (P>.999). The additive manufacturing group showed significantly lower tensile bond strength (1.23 ± 0.36 MPa) compared to the other groups (P<.001). Most specimens of heat-curing and subtractive manufacturing groups had mixed failure, but mixed failure and adhesive failure showed the same frequency in additive manufacturing group. Conclusion: The mean tensile bond strength of the subtractive manufacturing group was not significantly different from the heat-curing group. The additive manufacturing group showed significantly lower mean tensile bond strength than the other two groups.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.440-451
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• 1997

This study was designed to prospect the $^{111}In$-labelled paclitaxel as tumor imaging agent. In order to provide a taxol molecule with a functional group which is able to chelate In-111, taxol-DTPA conjugate and 2'-hemisuccinyltaxol were synthesized by esterification of taxol at C-2'on C-13 carbon with DTPA anhydride and succinic anhydride, respectively. Synthesis yield of the taxol derivatives was 34% for taxol-DTPA and 80% for 2'-hemisuccinyltaxol. Cytotoxicity of the taxol derivatives were measured by MTT method toward cell lines HT29, B16, P388, and CT26. The cytotoxic activities of the taxol derivatives were maintained, although less active than taxol. Radiolabelling of the taxol derivatives were proceeded directly with $^{111}InCl_3$ or indirectly with $^{111}In$-citrate(ligand-exchange method). The ligand-exchange method was not suitable because some precipitates appeared during the reaction. On the contrary, by direct radiolabelling method, we were able to obtain taxol-DTPA-$^{111}In$ in 100% radiochemical yield. However, 2'-hemisuccinyltaxol was not labelled by both methods. Yield and radiochemical purity of the radiolabelled com-pound were determined by HPLC, paper chromatography and instant thin layer chromatography. Taxol-DTPA-$^{111}In$ was characterized to be hydrophilic by lipophilicity test, and nearly non-adhesive to HT29, B16, P388, and CT26 by cell binding affinity test. Binding affinity of the taxol-DTPA-$^{111}In$ complex to serum proteins was also examined by protein precipitation with 30% trichloroacetic acid. The results showed that 30% of the taxol-DTPA-$^{111}In$ complex binds with serum proteins.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.331-338
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• 2008

Coal-tar enamel, blown asphalt and polyethylene have been used as wrapping materials of steel pipe in Korea. Currently, every manufacturer produces wrapped steel pipes with different materials and methods, and little research has been performed to get on wrapping methods and materials. In this research, properties of wrapping material of steel pipe used for water supply have been evaluated. All of the materials tested in this work were found to meet the standard. Among the wrapping materials of steel pipe tested, blown asphalt and coal-tar enamel were reasonable in price, and their mechanical properties were excellent. The quality of the wrapped steel pipes was being melted easily in organic solvent. When coated thick, the load of the steel pipes was higher than necessary. Tensile strength of cathode exfoliation and PE 3-layer wrapping method was excellent. The pulling intensity of T-Die PE 3-layer was stronger than PE fluidized in PE wrapping method. Cathode exfoliation area was smaller than PE fluidized. Mechanical property and thermo-property of T-Die PE 3-layer were excellent and its anti-chemical property was great. Liquid epoxy can change the property of coating materials depending on the hardening condition and resin selection. Polyurethane used in this test showed a less adhesive strength with steel pipes than epoxy. Moisture absorbance rate was higher than Epoxy's, however. To utilize polyurethane as wrapping materials, basic property of the matter should be improved followed by finding the best suited coating condition. The method of PE 3-layer by extrude method appeared to be the best in this study. However, identification of other wrapping materials requires further additional tests.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.55-59
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• 2012

We designed a new rapid detection method for volatilized formaldehyde from wood. The process was installed with volatilizing and collecting parts in an incubator. For rapid sampling of formaldehyde from wood, we pulverized the wood to sawdust, and used 0.15-2.0 mm particles for the tests. The highest sampling rate (94.8%) was obtained at 40 mL/min flow rate and $100^{\circ}C$. Under the optimized condition, we could collect the volatilized formaldehyde with good recovery rate. The developed method was applied to the monitoring of the formaldehyde from wood, and the measured concentrations were 0.7-4.6 ${\mu}g/g$ from natural wood, 5.9-12.3 ${\mu}g/g$ from preserved wood, and 5.9-211.5 ${\mu}g/g$ from chemical adhesive processed wood. From the results, we identified natural wood sawdust and chemically processed wood (medium density fiberboard, high density fiberboard, particle board) by the formaldehyde contents except preserved wood.

• Journal of Korean Society of Steel Construction
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• v.20 no.5
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• pp.583-590
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• 2008

Blasting has been applied in newly-built steel structures for cleaning forged surfaces and increasing the adhesive property of applied painting systems. However, the effect of the blast cleaning on fatigue behavior of welded joints is not clear. In this paper, fatigue tests were carried out on out-of-plane gusset welded joints and the effect of the blast cleaning on the fatigue behavior was studied. The curvature radius at the weld toe of the surface-treated specimens by using the blast method is larger than that of as-welded specimens. By the blast cleaning compressive residual stresses were induced into weld toes. The experimental results showed that the fatigue life of surface-treated specimens is longer than that of as-welded specimens, even though the fatigue life of surface-treated specimens and that of as-welded specimens are not clearly different in the high stress range. About a 160% increase in fatigue limit could be realized by using blast cleaning.

• Journal of Adhesion and Interface
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• v.10 no.3
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• pp.148-153
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• 2009

An atmospheric plasma pre-treatment method was applied to PU foam, Leather (Action), Rubber to improve its adhesion using solvent and water soluble type pressure sensitive adhesion in atmospheric plate type reactor. In order to investigate the optimum reaction condition of plasma treatment, type of reaction gas (nitrogen), rate of gas flow (30~100 mL/min), and reaction time (0~30 s) were examined in a plate plasma reactor. The result of the surface modification with respect to the treatment procedure was characterized by using SEM. Due to a de-crease of the contact angle of various materials, the greatest adhesion strength was achieved at optimum condition such as flow rate of 100 mL/min, reaction time of 10 second for an atmospheric plasma treatment of the PU foam, EVA foam, Leather (Action) and Rubber also resulted in the improvement of the adhesion.

• The Journal of Korea CHUNA Manual Medicine
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• v.4 no.1
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• pp.157-165
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• 2003

Low back pain (LBP) is a significant in today's society, with lifetime include factors associated with LBP ar reporter. Among the causes, aberration of posture may play a role in the development of LBP. Many investigators have assessed the curvature of spine in standing posture. But LBP is associated with Lumber Hyperlordosis of Hyperlordosis is controversial Subjects: In conservative treatment(acupuncture, herb med, manipulation & TENS. exercise, potural correction) for a 40 years old woman who had low back pain(V AS) be caused by decrease lumbar lordotic angie. Objectives: The object is change of lumbar lordotic angle of a 40 years old woman who had low back pain with Lumbar hyperlordosis, In conservative treatment. Method: In conservative treatment, We added taping therapy(mechanical correction taping of Kinesio Taping) about Lumbar Lordosis. Conclusion: We experienced a 40 years old woman who had love pack pain with Lumbar hyperlordosis. In conservative treatment, Her pain was Improved by additional taping therapy In company with decrease of Lumbar Lordosis. 1. abnormal spinal curvature, specially lumbar hyperlordosis act on induction & perpetuation agent for low back pain 2. In a patient had low back pain with lumbar hyperlordosis, change of lumbar lordotic angle is of utility value for the effect of treatment and assessment of prognosis. 3. pain control is more relative with change of lumbosacral angle than lumbar lordotic angle, in patient had low back pain with lumbar hyperlordosis. 4. mechanical taping therapy with elastic adhesive tape is effective for patient had low back pain with lumbar hyperlordosis

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.467-468
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• 2009

For the manufacture of the $CuGaS_2$, Cu, Ga and S were vapor-deposited in the named order. Among them, Cu and Ga were vapor-deposited by using the Evaporation method in consideration of their adhesive force to the substrate so that the composition of Cu and Ga might be 1 : 1, while the surface temperature having an effect on the quality of the thin film was changed from R.T.[$^{\circ}C$] to $150[^{\circ}C$] at intervals of 50[$^{\circ}C$]. As a result, at 300[$^{\circ}C$]of the Annealing temperature, their chemical composition was measured in the proportion of 1 : 1 : 2. It could be known from this experimental result that it is the optimum condition to conduct Annealing on the $CuGaS_2$ thin film under a vacuum when the $CuGaS_2$ thin film as an optical absorption layer material for a solar cell is manufactured.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.1
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• pp.85-93
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• 2007

The purpose of this study was to evaluate the microleakage of root-end filling material filled in blood contaminated root-end cavity and self-etching adhesive placed over blood contaminated resected root apices without root-end preparation. Extracted, human maxillary incisors, canines and mandibular premolar were randomly divided into four groups of 15 teeth each. After canal preparation, resection of the apex and root-end preparation, MTA and IRM were filled in the root-end cavity (A and B group). After canal preparation and resection of the apex, Clearfil SE Bond and Prompt L-Pop were applied over the contaminated root-end surfaces (C and D group). The roots were then subjected to 15cm of water pressure to simulate periapical microleakage stress. Data were analyzed using one-way ANOVA. The results were as follows : 1. All groups showed a tendency of decreasing microleakage in process of time after 2weeks later except IRM group. 2. After 2 weeks and 1 month, MTA group showed less microleakage significantly than other groups(p<0.05). After 2 months, Prompt L-Pop group showed less microleakage significantly than other groups(p<0.05). 3. After 9 months, there were no significant differences among four groups(p>0.05). Thus it is considered that apical sealing using adhesives system without root-end preparation is good method in endodontic surgery.

• Journal of Technologic Dentistry
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• v.35 no.1
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• pp.43-48
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• 2013

Purpose: This study aimed to investigate the shear bond strength for non-precious alloy castings without beryllium, which has been used repeatedly for economical reason. Methods: The Schmitz-Schulmeyer test method was used to evaluate the shear bond strength between the non-beryllium Ni-Cr alloy Vera Bond 2V(AlbaDent, Inc. USA) and the Ceramco 3(Dentstply, York, PA, USA) porcelain powder. The maximum loading and shear bond strength were measured. The average shear strength(MPa) was analyzed with the one-way ANOVA and the Tukey's test( =.05). The fracture specimens were examined using Microscope to determine the failure pattern. Results: The mean shear bond strengths(SD) in MPa were group A(100% new metal) control 28.72(3.31); group B(50% new + 50% reused) 27.28(1.13); group C(all reused) 26.61(5.47). Microscope examination showed that group A and B specimens presented mixed failure, and group C specimens showed adhesive failure. Conclusion: In conclusion, forward this non-precious alloy dose not contain beryllium for how should use a more systematic study and for future advanced research is performed giving effect to be considered desirable.