• Membrane and Water Treatment
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• 제9권1호
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• pp.1-7
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• 2018

The principal objective of this study is to investigate the effect of Polyethylene Glycol (PEG) crosslinking in Polyvinylidene Fluoride (PVDF) in immobilization of Fe and bimetallic Fe/Cu and Cu/Fe zero valent particles on the membrane and its efficiency on removal of nitrate in wastewater. PVDF/PEG polymer solution of three weight compositions was prepared to manipulate the viscosity of the polymer. PEG crosslinking was indirectly controlled by the viscosity of the polymer solution. In this study, PEG was used as a modifier of PVDF membrane as well as a cross-linker for the immobilization of the zero valent particles. The result demonstrates improvement in immobilization of metallic particles with the increase in crosslinking of PEG. Nitrate removal efficiency increases too.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제1권2호
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• pp.157-166
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• 1997

The biosorption performances of copper were investigated by the immobilized biomass of nonliving marine brown algae Undaria pinnatifida by each of the Ca-alginate method(Ca-ALG), Ba-alginate method(Ba-ALG), polyethylene glycol method(PEG), and carrageenan method (CARR). The copper removal performance increased but the copper uptake decreased as the biomass amount was increased. However, the copper uptake by the immobilized biomass increased with increasing initial copper concentration. Among the immobilization methods, the copper uptake decreased in the following sequence: Ca-ALG > Ba-ALG > PEG > CARR. The pattern of copper uptake by the immobilized biomass fitted the Langmuir isotherm better than the Freundlich isotherm. Desorption of deposited copper with 0.05 ~0.5M HCI, resulted in no changes of the copper uptake capacity of the immobilized biomass by the immobilization methods except for PEG, through five subsequent biosorption/desorption cycles. There was no damage to the immobilized biomass which retained its macroscopic appearance in repeated copper uptake/elution cycles.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.650-654
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• 2007

In our previous work, a method of pretreating lipase was developed to prevent loss of its activity during covalent immobilization. In this study, Rhizopus oryzae lipase was pretreated before immobilization and then immobilized on a silica gel surface. The effects of the various materials and conditions used in the pretreatment stage on the activity of immobilized lipase were investigated. Immobilized lipase pretreated with 0.1% of soybean oil had better activity than those pretreated with other materials. The optimal temperature, agitation speed, and pretreating time for lipase pretreatment were determined to be $40^{\circ}C$, 200rpm, and 45min, respectively. The activity of immobilized soybean oil pretreated lipase was 630U/g matrix, which is 20 times higher than that of immobilized non-pretreated lipase. In addition, immobilized lipase activity was maintained at levels exceeding 90% of its original activity after 10 reuses.

• The Journal of Korean Physical Therapy
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• 제19권3호
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• pp.19-30
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• 2007

Purpose: This study was performed to investigate the effects of NMES for recovery of skeletal muscle. Methods: The normal group consisted of healthy rat without cast immobilization. The control group was breeding at standard cage during 7 days after 2 weeks-cast immobilization on hind limb. The experimental group. I. received NMES application during days after 2 weeks-cast immobilization on hind limb. The effects were measured with NT-3 immunoreactivity in neuromuscular junction by light microscope. Results: Immunoreactivity of NT-3 at the neuromuscular junction was higher appeared experimental groups than control group. Then, There was a little detection in the normal and control group. Conclusion: These therapeutic interventions enhance expression of NT-3 at the neuromuscular junction. Also, NMES is considered to effect on a normal structural formation and NT-3 expression at the neuromuscular junction.

• 한국식품과학회지
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• 제20권4호
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• pp.541-546
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• 1988

Chitosan을 담체로 이용하여 aminoacylase를 고정화하는 조건을 연구한 결과는 다음과 같다. 담체의 최적 activation조건은 pH 6.0, glutaraldehyde 0.2%, 반응시간 120분이었다. 그리고 activated chitosan에 aminoacylase를 고정화하는데 가장 적당한 효소농도는 80mg/20ml 이었고, 이때 coupling time은 90분이 가장 적절하였다.

• Macromolecular Research
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• 제15권2호
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• pp.134-141
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• 2007

The direct chromatographic separation of enantiomers by chiral stationary phases (CSPs) has been extensively developed over the past two decades, and has now become the most popular method for the analytical and preparative separations of enantiomers. Polysaccharide derivatives coated onto silica gel, as CSPs, playa significantly important role in the enantioseparations of a wide range of chiral compounds using high-performance liquid chromatography (HPLC). Unfortunately, the strict solvent limitation of the mobile phases is the main defect in the method developments of these types of coated CSPs. Therefore, the immobilization of polysaccharide derivatives onto silica gel, via chemical bonding, to obtain a new generation of CSPs compatible with the universal solvents used in HPLC is increasingly important. In this article, our recent studies on the immobilization of polysaccharide derivatives onto the silica gel, as CSPs, through radical copolymerization with various vinyl monomers are reported. Polysaccharide derivatives, with low vinyl content, can be efficiently fixed onto silica gel with high chiral recognition.

• KSBB Journal
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• 제5권2호
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• pp.107-112
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• 1990

고정화단체로 제조된 다공성실리카를 3-aminopropyl-triethoxysilaneacetone 용액으로 표면처리하고 glutaraldehyde로 전화당효소를 공유결합시켜 진화당효소의 고정 화함량과 고정화활성도를 평가한 겨로가, 고정화함량 1200mg/ g, 활성도 26.9~ 70.2%로 우수한 고정화특성은 나타내였으며, 다상성살리카가 고정화담체로 활용되기 위한 구조직 특성을 가진 것으로 평가된다.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3458-3460
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• 2012

• Bulletin of the Korean Chemical Society
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• 제29권9호
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• pp.1790-1792
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• 2008

• Bulletin of the Korean Chemical Society
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• 제33권6호
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• pp.2099-2101
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• 2012