• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2513-2516
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• 2012

This study examined the effects of the epoxidized castor oil (ECO) and $Al_2O_3$ content on the thermal stability and fracture toughness of the diglycidylether of bisphenol-A (DGEBA)/ECO/$Al_2O_3$ ternary composites using a range of techniques. The thermal stability of the composites was decreased by the addition of ECO and $Al_2O_3$ nanoparticles. The fracture toughness of the composites was improved significantly by the addition of ECO and $Al_2O_3$ nanoparticles. The composite containing 3 wt % $Al_2O_3$ nanoparticles showed the maximum flexural strength. Scanning electron microscopy (SEM) revealed tortuous cracks in the DGEBA/ECO/$Al_2O_3$ composites, which prevented deformation and crack propagation.

• 한국분말재료학회지
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• 제24권3호
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• pp.242-247
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• 2017

In this study, the electroless nickel plating method has been investigated for the coating of Ni nanoparticles onto fine Al powder as promising energetic materials. The adsorption of nickel nanoparticles onto the surface of Al powders has been studied by varying various process parameters, namely, the amounts of reducing agent, complexing agent, and pH-controller. The size of nickel nanoparticles synthesized in the process has been optimized to approximately 200 nm and they have been adsorbed on the Al powder. TGA results clearly show that the temperature at which oxidation of Al mainly occurs is lowered as the amount of Ni nanoparticles on the Al surface increases. Furthermore, the Ni-plated Al powders prepared for all conditions show improved exothermic reaction due to the self-propagating high-temperature synthesis (SHS) between Ni and Al. Therefore, Al powders fully coated by Ni nanoparticles show the highest exothermic reactivity: this demonstrates the efficiency of Ni coating in improving the energetic properties of Al powders.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.255-255
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• 2009

In this work, nonvolatile nano-floating gate memory devices were fabricated with ZnO films and Al nanoparticles using the sputtering method on a glass substrate. Al nanoparticles acted as floating gate nodes in the devices. The fabricated device exhibits a threshold voltage shift of 1.7 V.

• 대한수의학회지
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• 제64권2호
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• pp.12.1-12.6
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• 2024

The current study aimed to determine the effect of silver and chitosan nanoparticles of size 10 to 30 nm on the dead of lice in vitro and in vivo to determine the optimal time and concentration to combat chicken lice. One hundred local chickens Gallus gallus domesticus were collected from Al-Diwaniyah province and 6 species of local chicken lice were isolated: Menacanthus stramineus, Menacanthus pallidullus, Menacanthus cornutus, Goniodes gigas, Cuclotogaster heterographus and Bonomiella columbae. The results of treating lice with chitosan and silver nanoparticles at concentrations (40, 60, and 80 mg/mL) in vitro and at different periods (5, 10, 15, and 30 minutes) after treatment showed that chitosan and silver nanoparticles at a concentration of 80 mg/mL are the most effective in killing lice. The dead rate of lice reached 100% after 15 minutes of treatment with chitosan nanoparticles and 100% in the case of silver nanoparticles after 30 minutes. The results of spraying chitosan and silver nanoparticles on the body of chickens infected with lice experimentally, based on the relative therapeutic efficacy within 30 minutes, indicated that silver nanoparticles were the most effective in completely killing lice in the group treated with a concentration of 80 mg/kg after 30 minutes, where the percentage of therapeutic efficacy was 96.7%. This was followed by chitosan nanoparticles at a concentration of 80 mg/kg, and the percentage of therapeutic efficiency was 91.5%. Chitosan and silver nanocomposite have a promising effect in the elimination of lice infestation in chickens.

• 대한기계학회논문집B
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• 제31권1호
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• pp.16-20
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• 2007

In this paper, convective heat transfer and flow characteristics of $Al_2O_3$ nanoparticles suspended in water flowing through uniformly heated tubes are experimentally investigated under laminar flow regime. The heat transfer coefficient and the pressure drop of nanoparticles suspended in water are experimentally presented according to the pumping power. In addition, the heat transfer coefficient and the pressure drop of $Al_2O_3$ nanoparticles suspended in water are compared with those of pure water under the fixed pumping power. It is shown that the heat transfer coefficient of $Al_2O_3$ nanofluids with 0.1% volume fraction is enhanced by about 12% although the increment of the pressure drop of those is 4% compared with those of pure water.

• 한국전기전자재료학회논문지
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• 제24권4호
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• pp.325-327
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• 2011

In this paper, nonvolatile nano-floating gate memory devices are fabricated with ZnO nanowires and Al nanoparticles on a $SiO_2/Si$ substrate. Al nanoparticles used as floating gate nodes are formed by the sputtering method. The fabricated device exhibits a threshold voltage shift of -1.5 V. In addition, we investigate the endurance and retention characteristics of the nano-floating gate memory device.

• 대한기계학회논문집B
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• 제36권5호
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• pp.509-515
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• 2012

본 논문은 수소를 연료로 하는 확산화염을 이용하여 알루미나 나노입자를 합성할 때, 합성되는 알루미나 나노입자의 특성에 미치는 화염온도의 영향을 조사하였다. 합성된 나노입자의 특성을 전자현미경 이미지, 결정구조 분석, 비표면적과 기공의 크기 분석, 화염온도 측정 등의 여러 특성분석 방법으로 조사하였다. 사용된 화염의 중심축 최고온도는 산화제의 산소농도가 19, 21, 30, 47%인 각각의 실험조건에서 1507.8K, 1593.8K, 1753.1K, 1998.7K으로 측정되었다. SEM 이미지 분석 및 BET 비표면적 측정을 통해서는 47% 산소농도인 경우에는 50 nm 수준의 독립적인 구형입자가 생성되었음을 확인할 수 있었으며, 19%와 21%의 경우에는 응집된 상태의 20-30 nm 수준의 입자를 볼 수 있었다. XRD 결과에서는 감마(${\gamma}$)-알루미나가 주를 이루는 것으로 판단되었다. 이상의 결과를 바탕으로 촉매 담체로 사용하기 위한 알루미나 나노입자를 연소합성 하기 위한 가장 적절한 조건으로 실험했던 네 경우 중에서는 산화제의 산소농도가 21%인 두 번째 경우를 선택할 수 있었다.

• 한국재료학회지
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• 제29권12호
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• pp.747-752
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• 2019

Environmental pollution remains a considerable health risk source all over the world; however, hazards are usually higher in developing countries. Iraq has long been suffering from the problem of pollution and how to treat pollution. Photocatalytic degradation has turned out to be most productive process for dye degradation. In this investigation, Rhodamine B (RhB), dye has been selected for degradation under visible light illumination. To address this issue, we fabricate erbium trioxide nanoparticles (Er₂O₃/NPs). Erbium trioxide nanoparticles are prepared and utilized for photo-catalytic degradation. The characterization of Er₂O₃/NPs is described and confirmed by utilizing of XRD (X-ray diffraction) and SEM (Scanning Electron Microscopy). The average size of Er₂O₃ nanoparticles is observed to be 16.00 nm. Er₂O₃/NPs is investigated for its ability of photo-catalytic degradation through certain selected parameters such as concentration and time. The methodological results show that the synthesized Er₂O₃/NPs is a good photo-catalytic for Rhodamine degradation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.60-62
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• 2004

CdTe nanoparticles were synthesized in aqueous solution by colloidal method. The absorption and photoluminescence(PL) spectrum of the synthesized CdTe nanoparticles revealed the strong exitonic peak in the visible region. Electroluminescence of CdTe nanoparticles were observed in the structure of Al/CdTe/PVK/ITO and Al/CdTe/PEDOT/ITO that were fabricated by spin coating of polyvinylcarvazole(PVK), poly(3,4-ethylenedioxythiophene(PEDOT) and CdTe nanoparticles. The turn-on voltages of Al/CdTe/PVK/ITO and Al/CdTe/PEDOT/ITO for electroluminescence were 5V and 6V, respectively. We identified that the reduction of turn-on voltage resulted from the increase of hole injection into the hole transport layer due to lower ionization energy of PEDOT.

• 한국수소및신에너지학회논문집
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• 제34권2호
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• pp.169-177
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• 2023

Phase stability diagrams were constructed for magnesium alanate (Mg(AlH₄)₂) nanoparticles to investigate the reversible hydrogen storage reaction by using density functional theory. Our findings indicate that bulk Mg(AlH₄)₂ shows favorable hydrogen release, but unfavorable hydrogen uptake (adsorption) reactions. However, for Mg(AlH₄)₂ nanoparticles, it was observed that hydrogen release and recharge can be achieved by controlling the particle size and temperature. Furthermore, by predicting the decomposition phase diagram of Mg(AlH₄)₂ nanoparticles with varying hydrogen partial pressure, it was discovered that reversible dehydrogenation reactions can occur even in relatively large nanoparticles by controlling the hydrogen partial pressure.