• Biomedical Science Letters
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• v.22 no.4
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• pp.184-188
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• 2016

The objective of this study was to develop a pH dependent oral matrix tablet containing probiotics. In this study, hydroxyl-propyl-methyl-cellulose (HPMC) and polyvinyl pyrrolidone K30 (PVP K-30) was utilized as a binder, sodium starch glycolate (SSG) was used as a disintegrant material for the tablet formulation. The disintegration test, hardness test, angle of response were performed to examine the characteristics of prepared tablet. Lactobacillus vitality test was applied to analyze the total Lactobacillus viable count. The results demonstrated that the pH dependent matrix tablet was prepared successfully and can thus be industrialized instead of the current methodologies used for preparation of conventional probiotics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.8
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• pp.650-653
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• 2009

Hybrid nanofibers made of $Cu_2O$ and polyvinyl pyrrolidone were fabricated by electrospinning on glass substrates. The current magnitude of the $Cu_2O$-PVP hybrid nanofibers is 10 times larger than that of pure PVP nanofibers. In addition, $Cu_2O$-PVP nanofibers possess high sensitivity to air at room temperature than pure PVP nanifibers.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.33-34
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• 2009

Hybrid nanofibers made of $Cu_2O$ and polyvinyl pyrrolidone were fabricated by electrospinning. The current magnitude of the $Cu_2O$-PVP hybrid nanofibers is 10 times larger than that of pure PVP nanofibers. In addition, $Cu_2O$-PVP nanofibers possess high sensitivity to air at room temperature.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.84-87
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• 2006

Batch binding experiments were performed to assess the recovery performance of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) bound to the unshielded and polymer (polyvinyl pyrrolidone. PVP)-shielded dye-ligand (Cibacron Blue 3GA) adsorbent. The adoption of a polymer-shielded, dye-ligand technique facilitated the elution efficiency of bound G3PDH. It was demonstrated that the recovery of G3PDH using polymer-shielded dye-ligand adsorption yielded higher elution efficiency, at 60.5% and a specific activity of 42.3 IU/mg, after a low ionic strength elution (0.15 M NaCl). The unshielded dye-ligand yielded lower elution efficiency. at 6.5% and a specific activity of 10.2 IU/mg.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.2979-2984
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• 2014

Silver nanoparticles have been synthesized by liquid-phase and alcohol reduction methods. Silver-doped silica-complex nanoparticles were prepared using a sol-gel process. The formation, structure, morphology, and particle size of the nanoparticles have been studied using several techniques. Silver nanoparticles of size of 30-40 nm were formed successfully by alcohol reduction. TEM images show that both the concentration and the molecular weight of polyvinyl pyrrolidone (PVP) considerably affect the size of the emerging silver nanoparticles. The number of silver-doped silica-complex particles increased by a mercapto-group treatment that showed a narrower size distribution than that of silica treated with amino groups. The silver/polyester and silver-doped silica/polyester masterbatch chips showed excellent antibacterial activity against Staphylococcus aureus and Escherichia coli.

• YAKHAK HOEJI
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• v.60 no.1
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• pp.46-50
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• 2016

The purpose of this study was the development of sustained-release lyogel of chlorhexidine in the treatment of periodontal diseases. A sustained-release chlorhexidine lyogel (CHX-G) was formulated, based on Eudragit$^{(R)}$ (1~3%), polyvinyl pyrrolidone (PVP) (0~10%), triacetin (20~40%), hydroxy ethyl cellulose (HEC) (1%) and glycerin. In vitro studies were performed to determine the release rate of chlorhexidine from CHX-Gs using dialysis tube. Our results suggest that the release rate of chlorhexidine from lyogel could be controlled by changing the lyogel compositions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.551-552
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• 2006

This study was attended to demonstrate synthesis of silver nanoparticles stabilized with polymer and their applicability to printed electronics. Silver nanoparticles were synthesized by reduction of silver nitrate in aqueous solution in the presence of polyvinyl pyrrolidone (PVP) as a stabilizer. The ink used here is composed of 50 wt% Ag NP, 15 wt% humectant and then were printed on polyimide film. Particle deposit morphologies were controlled by varying the ink compositions. Printed silver patterns and dots were cured on a convection oven in air at $300^{\circ}C$ for 60 min. The printed patterns show good shape definition and the resistivity of the printed films is about $5{\mu}{\Omega}{\cdot}cm$.

• Progress in Superconductivity and Cryogenics
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• v.24 no.4
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• pp.55-58
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• 2022

Carbon-based doping to MgB₂ superconductor is the simplest approach to enhance the critical current densities under magnetic fields. Carbon quantum dots is synthesized in this work as a carbon provider to MgB₂ superconductors. Polyvinyl Pyrrolidone is pyrolyzed and dispersed in dimethylfomamide solvent as a dopant to the mixture of Mg and B powders. Doped MgB₂ bulk samples clearly show the decrease of a-axis lattice constant, grain refinements, and broadening of FWHM of diffraction peaks compared to un-doped MgB₂ possibly due to the carbon substitution and/or boron vacancy at the boron site in MgB₂ lattice. Also, high-field J_c for the doped MgB₂ is enhanced significantly with the crossover about 3 T at 5 & 20 K when increasing the doping of carbon quantum dots.

• Polymer(Korea)
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• v.37 no.4
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• pp.526-532
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• 2013

The effect of CNT dispersion method on rheological and electrical properties of polystyrene/carbon nanotube (PS/CNT) nanocomposites via latex technology was compared. The nanocomposites were prepared through freeze-drying the dispersed suspension comprised of CNTs and PS particles. In this study, physical dispersion method, either sodium dodecylsulfate (SDS) addition or polyvinyl pyrrolidone (PVP) wrapping, was employed to prevent the deterioration of intrinsic properties of CNT caused by chemical modification. The physical method applied to latex technology was very effective in CNT dispersion. With SDS addition, the enhancement of rheological properties was low compared to PVP wrapping because the properties of matrix were deteriorated due to the incorporation of low molecular weight SDS. The electrical percolation threshold of PS/SDS-stabilized CNT and PS/PVP-wrapped CNT nanocomposites was 0.23 and 0.90 wt%, respectively. The enhancement of electrical conductivity was low in the case of PVP wrapping because the non-conducting PVPs wrapped around CNT restricted the electrical connection between CNTs.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.2
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• pp.67-72
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• 2012

In recent days, the wire width of IC is narrowed and the degree of integration of IC is increased to obtain the higher capacity of the devices in electronic industry. And then the surface quality of FCCL(Flexible Copper Clad Laminate) became increasingly important. Surface defects on FCCL are bump, scratch, dent and so on. In particular, bumps cause low reliability of the products. Even though there are bumps on the surface, if leveling characteristic of plating solution is good, it does not develop significant bump. In this study, the leveling characteristics of additives are investigated. The objective of study is to improve the leveling characteristic and reduce the surface step through additives and plating conditions. The additives in the electrodeposition bath are critical to obtain flat surface and free of defects. In order to form flat copper surface, accelerator, suppressor and leveler are added to the stock solution. The reason for the addition of leveler is planarization surface and inhibition of the formation of micro-bump. Levelers (SO(Safranin O), MV(Methylene Violet), AB(Alcian Blue), JGB(Janus Green B), DB(Diazine Black) and PVP(Polyvinyl Pyrrolidone) are used in copper plating solution to enhance the morphology of electroplated copper. In this study, the nucleation and growth behavior of copper with variation of additives are studied. The leveling characteristics are analyzed on artificially fabricated Ni bumps.