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Printing Performance Evaluation of Water-dispersed Pigment Ink according to Additive Conditions of Film Substrate Surface Coating Agent (필름기재 표면 코팅제의 첨가물질 조성 조건에 따른 수분산 안료잉크의 프린팅 성능 평가)

  • Hyeok-Jin Kim;Hye-Ji Seo;Eun-Ha Kang;Min-Woo Han;Dong-Hyeon Lee;Dong-Jun Kwon;Jin-Pyo Hong
    • Textile Coloration and Finishing
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    • v.35 no.4
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    • pp.196-205
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    • 2023
  • Water-dispersed pigment is on-going study for without air pollution in the textile and print industry. Primer treatment is essential for the substrate to improve the printing quality of eco-friendly water-dispersed pigment ink. Otherwise in the case of untreated primer, the water-dispersed pigment ink will dry onto the surface and cause defective images. This study was conducted on film substrate coating (primer) to fix eco-friendly water-dispersed pigment ink on film substrate. The drying, bleeding, and color strength of the pigment ink were examined depending on the composition and mixing ratio of the coating solution. The mixing ratio of silica gel in the coating film is increased to 0, 0.5, 1, 2 and 3 and results that DK-1-3 of silica gel ratio of 1 showed the lowest bleeding such as 52%, the letter thickness of 0.76mm and DK-1-5 of SG ratio of 3 showed the highest bleeding such as 304%, the letter thickness of 2.02mm. The mixing ratio of SPA in the coating film is increased to 2.5, 5, 7.5, SPA ratio of 7.5 has a bleeding ratio of 9% and letter thickness of 0.544mm. It showed the closest value to 0.5mm. According to the result, the optimal mixing ratio of binder, polymer coagulant, silica gel is 100:7.5:1.

Shear bond strength of dental CAD-CAM hybrid restorative materials repaired with composite resin (치과용 복합레진으로 수리된 CAD-CAM hybrid 수복물의 전단결합강도)

  • Moon, Yun-Hee;Lee, Jonghyuk;Lee, Myung-Gu
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.193-202
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    • 2016
  • Purpose: This study was performed in order to assess the effect of the surface treatment methods and the use of bonding agent on the shear bond strength (SBS) between the aged CAD-CAM (computer aided design-computer aided manufacturing) hybrid materials and added composite resin. Materials and methods: LAVA Ultimate (LU) and VITA ENAMIC (VE) specimens were age treated by submerging in a $37^{\circ}C$ water bath filled with artificial saliva (Xerova solution) for 30 days. The surface was ground with #220 SiC paper then the specimens were divided into 9 groups according to the combination of the surface treatment (no treatment, grinding, air abrasion with aluminum oxide, HF acid) and bonding agents (no bonding, Adper Single Bond 2, Single Bond Universal). Each group had 10 specimens. Specimens were repaired (added) using composite resin (Filtek Z250), then all the specimens were stored for 7 days in room temperature distilled water. SBS was measured and the fractured surfaces were observed with a scanning electron microscope (SEM). One-way ANOVA and Scheffe test were used for statistical analysis (${\alpha}=.05$). Results: Mostly groups with bonding agent treatment showed higher SBS than groups without bonding agent. Among the groups without bonding agent the groups with aluminum oxide treatment showed higher SBS. However there was no significant difference between groups except two subgroups within LU group, which revealed a significant increase of SBS when Single Bond Universal was used on the ground LU specimen. Conclusion: The use of bonding agent when repairing an aged LAVA Ultimate restoration is recommended.

Effects of Low Level of Levan Feeding on Serum Lipids, Adiposity and UCP Expression in Rats (저농도 레반 공급이 혈중 지질 및 체지방 형성과 UCP 발현에 미치는 영향)

  • 강순아;홍경희;장기효;김소혜;조여원
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.5
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    • pp.788-795
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    • 2002
  • This study described the effect of levan (9-2,6-linked fructose polymer) feeding on serum lipids, adiposity and uncoupling protein (UCP) expression in growing rats. Levan was synthesized from sucrose using bacterial levansucrase. UCP is a mitochondrial protein that uncouples the respiratory chain from oxidative Phosphorylation and generates heat instead of ATP, thereby increase energy expenditure. We observed that 3% or 5% levan containing diet reduced serum triglyceride levels, visceral and peritoneal fat mass and induced the UCP expression in rats fed high fat diet in previous study. To determine whether the intake of low level of levan may have the hypolipidemic and anti-obesity effect, 4 wk old Sprague Dawley male rats were fed AIN-76A diet for 6 wk, and sub-sequently fed 1% or 2% levan solution for further 5 wk. Intake of 1% levan in liquid form reduced serum triglyceride and serum total cholesterol levels to 50% and 66% of control group, respectively. Although epididymal and peritoneal fat masses were not affected by levan feeding, visceral fat mass was lower in 1% levan group compared to control group. The expression of UCP2 mRNA in brown adipose tissue, skeletal muscle and hypothalamus and UCP3 mRNA in skeletal muscle were not changed by levan feeding, while the UCP2 mRNA in white adipose tissue was up-regulated by levan feeding. In conclusions, intake of low level of levan solution reduced serum triglyceride and total cholesterol, restrained the visceral fat accumulation and increased UCP expression in white adipose tissue in rats. This study suggests that hypolipidemic and anti-obesity effect of levan attributed to anti-lipogenesis and inefficeint energy utilization by up-regulation of UCPs.

Biocompatibility and Histopathologic Change of the Acellular Xenogenic Pulmonary Valved Conduit Grafted in the Right Ventricular Outflow Tract (우심실 유출로에 이식한 무세포화 이종 폐동맥 판막도관의 생체 적합성 및 조직병리학적 변화양상에 대한 연구)

  • 허재학;김용진;박현정;김원곤
    • Journal of Chest Surgery
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    • v.37 no.6
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    • pp.482-491
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    • 2004
  • Background: The xenogenic or allogenic valves after in Vitro repopulation with autologous cells or in vivo repo-pulation after acellularization treatment to remove the antigenicity could used as an alternative to synthetic polymer scaffold. In the present study, we evaluated the process of repopulation by recipient cell to the acellu-larized xenograft treated with NaCl-SDS solution and grafted in the right ventricular outflow tract. Material and Method: Porcine pulmonary valved conduit were treated with. NaCl-SDS solution to make the grafts acellularized and implanted in the right ventricular outflow tract of the goats under cardiopulmonary bypass. After evaluating the functions of pulmonary valves by echocardiography, goats were sacrificed at 1 week, 1 month, 3 months, 6 months, and 12 months after implantation, respectively. After retrieving the implanted valved conduits, histopathologic examination with Hematoxylin-Eosin, Masson' trichrome staining and immunohistochemical staining was performed. Result: Among the six goats, which had been implanted with acellularized pulmonary valved conduits, five survived the expected time period. Echocardiographic examinations for pulmonary valves revealed good function except mild regurgitation and stenosis. Microscopic analysis of the leaflets showed progressive cellular in-growth, composed of fibroblasts, myofibroblasts, and endothelial cells, into the acellularized leaflets over time. Severe inflammatory respon-se was detected in early phase, though it gradually decreased afterwards. The extracellular matrices were regenerated by repopulated cells on the recellularized portion of the acellularized leaflet. Conclusion: The acellularized xenogenic pulmonary valved conuits were repopulated with fibroblasts, myofibroblasts, and endothelial cells of the recipient and extracellullar matrices were regenerated by repopulted cells 12 months after the implantation. The functional integrity of pulmonary valves was well preserved. This study showed that the acellularized porcine xenogenic valved conduits could be used as an ideal valve prosthesis with long term durability.

Production of Alternative Coagulant Using Waste Activated Alumina and Evaluation of Coagulation Activity (폐촉매 부산물로부터 대체 응집제 제조 및 응집성능 평가)

  • Lee, Sangwon;Moon, Taesup;Kim, Hyosoo;Choi, Myungwon;Lee, Deasun;Park, Sangtae;Kim, Changwon
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.7
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    • pp.514-520
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    • 2014
  • In this study, the production potential of alternative coagulant ($Al_2(SO_4)_3$ solution) having the identical coagulation activity with respect to the commercial coagulant was investigated. The raw material of alternative coagulant was a spent catalyst including aluminium (waste activated alumina) generated in the manufacturing process of the polymer. The alternative coagulant was produced through a series of processes: 1) intense heat and grinding, 2) chemical polymerization and substitution with $H_2SO_4$ solution, 3) dissolution and dilution and 4) settling and separation. To determine the optimal operating conditions in the lab-scale autoclave and dissolver, the content of $Al_2O_3$ in alternative coagulant was analyzed according to changes of the purity of sulfuric acid, reaction temperature, injection ratio of sulfuric acid and water in the dissolver. The results showed that the alternative coagulant having the $Al_2O_3$ content of 7~8% was produced under the optimal conditions such as $H_2SO_4$ purity of 50%, reaction temperature of $120^{\circ}C$, injection ratio of $H_2SO_4$ of 5 times and injection ratio of water of 2.3 times in dissolver. In order to evaluate the coagulation activity of the alternative coagulant, the Jar-test was conducted to the effluent in aerobic reactor. As a result, in both cases of Al/P mole of 1.5 and 2.0, the coagulation activity of the alternative coagulant was higher than that of the existing commercial coagulant. When the production costs were compared between the alternative and commercial coagulant through economic analysis, the production cost reduction of about 50% was available in the case of the alternative coagulant. In addition, it was identified that the alternative coagulant could be applied at field wastewater treatment plant without environmental problem through ecological toxicity testing.

The Effect of Platelet Derived Growth Factor - BB Loaded Chitosan/Calcium Metaphosphate on Bone Regeneration (혈소판유래성장인자를 함유한 Chitosan/Calcium Metaphosphate의 골조직재생효과에 관한 연구)

  • Lee, Seung-Yeol;Seol, Yang-Jo;Lee, Yong-Moo;Lee, Ju-Yeon;Lee, Seung-Jin;Kim, Suk-Young;Ku, Young;Rhyu, In-Chul;Han, Soo-Boo;Choi, Sang-Mook;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
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    • v.31 no.1
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    • pp.1-23
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    • 2001
  • Chitosan is biodegradable natural polymer that has been demonstrated its ability to improve wound healing, and calcium metaphosphate(CMP) is a unique class of phosphate minerals having a polymeric structure. In this study, chitosan/CMP and platelet derived growth factor(PDGF-BB) loaded chitosan/CMP sponges were developed, and the effect of the sponges on bone regeneration and their possibility as scaffolds for bone formation by three-dimensional osteoblast culture were examined. PDGF-BB loaded chitosan/CMP sponges were prepared by freeze-drying of a mixture of chitosan solution and CMP powder, and soaking in a PDGF-BB solution. Fabricated sponge retained its 3-dimensional porous structure with $100-200\;{\mu}m$ pores. The release kinetics of PDGF-BB loaded onto the sponge were measured in vitro with $^{125}I-labeled$ PDGF-BB. In order to examine their possibility as scaffolds for bone formation, fetal rat calvarial osteoblastic cells were isolated, cultured, and seeded into the sponges. The cell-sponge constructs were cultured for 28 days. Cell proliferation, alkaline phosphatase activity were measured at 1, 7, 14 and 28 days, and histologic examination was performed. In order to examine the effect on the healing of bone defect, the sponges were implanted into rat calvarial defects. Rats were sacrificed 2 and 4 weeks after implantation and histologic and histomorphometrical examination were performed. An effective therapeutic concentration of PDGF-BB following a high initial burst release was maintained throughout the examination period. PDGF-BB loaded chitosan/CMP sponges supported the proliferation of seeded osteoblastic cells as well as their differentiation as indicated by high alkaline phosphatase activities. Histologic findings indicated that seeded osteoblastic cells well attached to sponge matrices and proliferated in a multi-layer fashion. In the experiments of implantation in rat calvarial defects, histologic and histomorphometric examination revealed that chitosan/CMP sponge promoted osseous healing as compared to controls. PDGF-BB loaded chitosan/CMP sponge further echanced bone regeneration. These results suggested that PDGF-BB loaded chitosan/CMP sponge was a feasable scaffolding material to grow osteoblast in a three-dimentional structure for transplantation into a site for bone regeneration.

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Chemistry of mist deposition of organic polymer PEDOT:PSS on crystalline Si

  • Shirai, Hajime;Ohki, Tatsuya;Liu, Qiming;Ichikawa, Koki
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.388-388
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    • 2016
  • Chemical mist deposition (CMD) of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) was investigated with cavitation frequency f, solvent, flow rate of nitrogen, substrate temperature $T_s$, and substrate dc bias $V_s$ as variables for efficient PEDOT:PSS/crystalline (c-)Si heterojunction solar cells (Fig. 1). The high-speed camera and differential mobility analysis characterizations revealed that average size and flux of PEDOT:PSS mist depend on f, solvent, and $V_s$. The size distribution of mist particles including EG/DI water cosolvent is also shown at three different $V_s$ of 0, 1.5, and 5 kV for a f of 3 MHz (Fig. 2). The size distribution of EG/DI water mist without PEDOT:PSS is also shown at the bottom. A peak maximum shifted from 300-350 to 20-30 nm with a narrow band width of ~150 nm for PEDOT:PSS solution, whose maximum number density increased significantly up to 8000/cc with increasing $V_s$. On the other hand, for EG/water cosolvent mist alone, the peak maximum was observed at a 72.3 nm with a number density of ~700/cc and a band width of ~160 nm and it decreased markedly with increasing $V_s$. These findings were not observed for PEDOT:PSS/EG/DI water mist. In addition, the Mie scattering image of PEDOT:PSS mist under white bias light was not observed at $V_s$ above 5 kV, because the average size of mist became smaller. These results imply that most of solvent is solvated in PEDOT:PSS molecule and/or solvent is vaporized. Thus, higher f and $V_s$ generate preferentially fine mist particle with a narrower band width. Film deposition occurred when $V_s$ was impressed on positive to a c-Si substrate at a Ts of $30-40^{\circ}C$, whereas no deposition of films occurred on negative, implying that negatively charged mist mainly provide the film deposition. The uniform deposition of PEDOT:PSS films occurred on textured c-Si(100) substrate by adjusting $T_s$ and $V_s$. The adhesion of CMD PEDOT:PSS to c-Si enhanced by $V_s$ conspicuously compared to that of spin-coated film. The CMD PEDOT:PSS/c-Si solar cell devices on textured c-Si(100) exhibited a ${\eta}$ of 11.0% with the better uniformity of the solar cell parameters. Furthermore, ${\eta}$ increased to 12.5% with a $J_{sc}$ of $35.6mA/cm^2$, a $V_{oc}$ of 0.53 V, and a FF of 0.67 with an antireflection (AR) coating layer of 20-nm-thick CMD molybdenum oxide $MoO_x$ (n= 2.1) using negatively charged mist of 0.1 wt% 12 Molybdo (VI) phosphoric acid n-Hydrate) $H_3(PMo_{12}O_40){\cdot}nH_2O$ in methanol. CMD. These findings suggest that the CMD with negatively charged mist has a great potential for the uniform deposition of organic and inorganic on textured c-Si substrate by adjusting $T_s$ and $V_s$.

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Improvement of L-Lysine Productivity by Using Cell Fusion and Immobilized System (세포융합과 고정화 시스템을 이용한 L-Lysine의 생산성 향상)

  • Ryu, Beung-Ho;Kim, Hye-Sung;Roh, Myung-Hoon;Park, Bob-Gyu;Chung, Jong-Soon;Bai, Ki-Chul
    • Korean Journal of Food Science and Technology
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    • v.21 no.1
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    • pp.154-163
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    • 1989
  • This studies were designed to improve the productivity of L-lysine by protoplast fusion and immobilized system of fusants using strains of Brevibacterium flavum ATCC 21528, Brevibacterium lactofermentum ATCC 21086 and Corynebacterium glutamicum 820. Mutants were isolated with concentration method of $300{\mu}g/ml$ penicillin-G after treatment of $250{\mu}g/ml$ N-methyl-N-nitro-N-nitrosoguanidine. B. flavum $37-2(Hos^-,\;Kan^r,\;AEC^r)$, B. lactofermentum $6-2(Ile^-,\;Val^-,\;Str^r,\;AEC^r)$ and C. glutamicum 57-5$(Met^-,\;Thr^-,\;Rif^r,\;AEC^r)$ were isolated from mutants. Protoplasts were induced by being incubated with $500{\mu}g/ml$ lysozyme of lysis solution for 6 hr and the ratio of protoplast formation and regeneration were ranging from 97-99% and 33-37%, respectively. Fusion frequencies of fusants of BBFL 21, BCFG 37 and BCLG 59 were shown in the range from $1.25{\times}10^{-6}\;to\;5.83{\times}10^{-7}$ under the optimum conditions. The fusant BBFL 21 showed the highest productivity of $411.1\;ng/ml{\cdot}hr$ L-lysine in the lysine productivity broth at $30^{\circ}C$ for 72hr. In the immobilization systems, fusant BBFL 21 was employed in various polymer matrices such as sodium alginate, polyacrylamide, agar and ${\alpha}-carrageena$. The immobilization of sodium alginate showed the highest productivity of $413\;ng/ml{\cdot}hr$ L-lysine in the batch system. Continuous fermentation of immobilization system by using tube fermentor was produced the highest productivity $416.7\;ng/ml{\cdot}hr $ L-lysine under optimum condition.

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EFFECT OF FLUORIDE IN NATURAL POLYMER ON ENAMEL DEMINERALIZATION (천연고분자 화합물을 이용한 불소겔이 법랑질 탈회에 미치는 영향)

  • Kim, Ji-Yeon;Lee, Sang-Ho;Lee, Nan-Young
    • Journal of the korean academy of Pediatric Dentistry
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    • v.37 no.1
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    • pp.35-43
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    • 2010
  • We have developed a sodium fluoride containing gelatin and methyl cellulose gel. Cariostatic abilities of those gel were investigated and compared with APF gel and fluoride varnish($Cavityshield^{TM}$). We prepared the bovine tooth samples and divided into two surface, control side and experimental side in same specimen for exclusion of difference between specimens. The experiment was consisted of 4 groups : (I) APF gel : (II) $Cavityshield^{TM}$ : (III) Gelatin F gel : (IV) Methyl cellulose F gel Decalcification were produced by placing each specimen into artificial acidic solution(pH 4.0) for 72 hours. Surface microhardness were measured and depth of demineralization lesion were measured by polarizing light microscope. The results were as follows: 1. The difference of VHN between control and experimental side is smallest in group I (p<0.05). 2. The largest difference was shown in group II (p<0.05). 3. There were no significant difference between group III and IV in microhardness test (p>0.05). 4. The difference of lesion depth is smallest in group I (p<0.05). 5. There were no significant difference between group II, III and IV in lesion depth (p>0.05). The result of the present study indicate that the fluoride containing gelatin and methyl cellulose gel is more effective than APF gel and is similar to fluoride varnish application for prevention of demineralization.

Effect of Cardanol Content on the Antibacterial Films Derived from Alginate-PVA Blended Matrix (알지네이트-폴리비닐알콜 블랜드 항균 필름 제조를 위한 카다놀 함량의 영향)

  • Ahn, Hee Ju;Kang, Kyung Soo;Song, Yun Ha;Lee, Da Hae;Kim, Mun Ho;Lee, Jae Kyoung;Woo, Hee Chul
    • Clean Technology
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    • v.28 no.1
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    • pp.24-31
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    • 2022
  • Petroleum-based plastics are used for various purposes and pose a significant threat to the earth's environment and ecosystem. Many efforts have been taken globally in different areas to find alternatives. As part of these efforts, this study manufactured alginate-based polyvinyl alcohol (PVA) blended films by casting from an aqueous solution prepared by mixing 10 wt% petroleum-based PVA with biodegradable, marine biomass-derived alginate. Glutaraldehyde was used as a cross-linking agent, and cardanol, an alkyl phenol-based bio-oil extracted from cashew nut shell, was added in the range of 0.1 to 2.0 wt% to grant antibacterial activity to the films. FTIR and TGA were performed to characterize the manufactured blended films, and the tensile strength, degree of swelling, and antibacterial activity were measured. Results obtained from the FTIR, TGA, and tensile strength test showed that alginate, the main component, was well distributed in the PVA by forming a matrix phase. The brittleness of alginate, a known weakness as a single component, and the low thermal durability of PVA were improved by cross-linking and hydrogen bonding of the functional groups between alginate and PVA. Addition of cardanol to the alginate-based PVA blend significantly improved the antibacterial activity against S. aureus and E. coli. The antibacterial performance was excellent with a death rate of 98% or higher for S. aureus and about 70% for E. coli at a contact time of 60 minutes. The optimal antibacterial activity of the alginate-PVA blended films was found with a cardanol content range between 0.1 to 0.5 wt%. These results show that cardanol-containing alginate-PVA blended films are suitable for use as various antibacterial materials, including as food packaging.