• BMB Reports
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• 제44권2호
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• pp.77-86
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• 2011

Over the years, nanostructures have been developed to enable to support enzyme usability to obtain highly selective and efficient biocatalysts for catalyzing processes under various conditions. This review summarizes recent developments in the nanostructures for enzyme supporters, typically those formed with various inorganic materials. To improve enzyme attachment, the surface of nanomaterials is properly modified to express specific functional groups. Various materials and nanostructures can be applied to improve both enzyme activity and stability. The merits of the incorporation of enzymes in inorganic nanomaterials and unprecedented opportunities for enhanced enzyme properties are discussed. Finally, the limitations encountered with nanomaterial-based enzyme immobilization are discussed together with the future prospects of such systems.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1619-1624
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• 2014

A new series of carbazole based 2,4-disubstituted thiazole derivatives were synthesized. All the synthesized compounds were tested for their cytotoxicity against three different cancer cell lines A549, MCF-7, and HT29. Some of these compounds showed good cytotoxicity. These compounds were also evaluated for antioxidant activity. Compounds 3a, 3b, 3d-f and 3i showed higher antioxidant activity than standard BHT.

• Toxicological Research
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• 제26권2호
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• pp.95-100
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• 2010

Nanoparticle exposure assessment presents a unique challenge in the field of occupational and environmental health. With the commercialization of nanotechnology, exposure usually starts from the workplace and then spreads to environment and consumer exposure. This report discusses the current trends of nanoparticle exposure assessment, including the definition of nanotechnology relevant terms, essential physicochemical properties for nanomaterial characterization, current international activities related nanomaterial safety, and exposure assessment standard development for nanotechnology. Further this report describes challenges of nanoparticle exposure assessment such as background measurement, metrics of nanoparticle exposure assessment and personal sampling.

• KSBB Journal
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• 제23권6호
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• pp.546-550
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• 2008

본 연구에서는 아스타잔틴의 각종 유기용매와 물에 대한 용해도와 산화, 빛, 온도 및 pH에 의한 아스타잔틴의 안정성을 검토하였다. 아스타잔틴은 유기용매인 아세톤과 아세트산에 비교적 용해도가 높았으며 물에는 거의 용해되지 않았다. 아스타잔틴의 용해도에 미치는 pH의 영향을 검토한 결과, 산성 조건 (pH 2)에서는 중성이나 염기성 조건에 비하여 용해도가 10-20배 증가하였다. 아스타잔틴은 산화와 빛에 대한 안정성이 매우 낮았으며, pH 3에서도 안정성이 급격히 떨어지는 것으로 조사되었다. 온도에 대한 영향을 조사한 결과, 상온 보관시에도 아스타잔틴이 쉽게 분해되었으며, 특히 $100^{\circ}C$에서 5초 동안 가열할 경우 아스타잔틴이 90% 이상 분해되었다. 결론적으로 아스타잔틴을 식품이나 화장품 등의 산업적 활용을 위해서는 안정성과 용해도 개선이 요구되는 것으로 판단되었다.

• Advances in nano research
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• 제16권1호
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• pp.53-69
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• 2024

Advancements in the technology of building materials has led to diverse applications of nanomaterials with the aim to monitor concrete structures. While there are myriad instances of the use of nanoparticles in building materials, the production of smart nano cement-composites is often expensive. Thereupon, this research aims to discover a sustainable nanomaterial from tyre waste using the pyrolysis process as part of the green manufacturing circle. Here, Nano Structure Tyre-Char (NSTC) is introduced as a zero-dimension carbon-based nanoparticle. The NSTC particles were characterized using various standard characterization techniques. Several salient results for the NSTC particles were obtained using microscopic and spectroscopic techniques. The size of the particles as well as that of the agglomerates were reduced significantly using the milling process and the results were validated through a scanning electron microscope. The crystallite size and crystallinity were found to be ~35nm and 10.42%, respectively. The direct bandgap value of 5.93eV and good optical conductivity at 786 nm were obtained from the ultra violet visible spectroscopy measurements. The thermal analysis reveals the presence of a substantial amount of carbon, the rate of maximum weight loss, and the two stages of phase transformation. The FT-Raman confirms the presence of carboxyl groups and a ID/IG ratio of 0.83. Water contact angle around 140° on the surface implies the highly hydrophobic nature of the material and its low surface energy. This characteristic process assists to obtain a sustainable nanomaterial from waste tyres, contributing to the development of a smart building material.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2004년도 하계학술연구발표회 논문개요집
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• pp.5-6
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• 2004

• 월간포장계
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• 통권273호
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• pp.55-62
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• 2016

• 한국전기전자재료학회논문지
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• 제32권2호
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• pp.161-164
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• 2019

This study describes the development of graphene-$TiO_2$ conjugates for the enhancement of the photocatalytic efficiency of $TiO_2$. Graphene-based hybrid nanomaterials have attracted considerable attention because of the unique and advantageous properties of graphene. In the proposed hybrid nanomaterial, graphene serves as an electron acceptor to ensure fast charge transfer. Effective charge separation can, therefore, be achieved to slow down electron-hole recombination. This results in an enhancement of the photocatalytic activity of $TiO_2$. In addition, increased adsorption and interactions with the adsorbed reagents also lead to an improvement in the photocatalytic activity of graphene-$TiO_2$ hybrid nanomaterials. The acquired result is encouraging in that the photocatalytic activity of $TiO_2$ was initiated using visible light (630 nm) instead of the typical UV light.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1237-1239
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• 2013

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.2042-2049
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• 2019

Ten gizzard and three flesh samples of the broiler were collected from different locations in Tehsil Gujar Khan District Rawalpindi, Pakistan. The samples were dried, crushed and ground. Pellets were prepared by pressing the powder of the samples and that of the Bovine liver 1577c reference material obtained from NIST, USA. Proton induced X-ray emission (PIXE) installed at National Center for Physics, Islamabad, Pakistan has been used as a reliable and improved technique to determine concentration of various major/trace and toxic elements e.g. S, Cl, K, Ca, Cl, Fe, Cu, Mn, Co, Zn, Ti, Cd, Ga, Cr, V and Ni, in the Gizzard and Flesh samples of the broiler. The concentrations of all the detected elements in the samples are statistically significant. The certified and measured values of the elements in the reference material were in agreement with each other within a deviation of 7%. S, Cl, K and Ca are within tolerable limits and are good for human consumption. Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn were more than the acceptable limits of World Health Organization, WHO whereas Ga, As, Sn, Sb and Pb are not detected in most of the samples.