Artykuły w czasopismach: „Composite metal nanoparticles”

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Wang, Ji Fen, Hua Qing Xie, Zhong Xin, Yang Li i Jing Li. "Thermal Properties of Composites Containing Metal Oxide Nanoparticles". Materials Science Forum 694 (lipiec 2011): 146–49. http://dx.doi.org/10.4028/www.scientific.net/msf.694.146.

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We prepared a series of paraffin wax (PW) based phase change composite containing ZnO, Al2O3 and Fe2O3 nanoparticles, respectively. DSC results showed that there is a decrease trend in phase change latent heat capacity (Ls) with an increase of metal oxide nanoparticle loadings. ZnO/PW has higher Ls than those of Fe2O3/PW and Al2O3/PW with same metal oxide nanoparticle loadings. Transient short-hot-wire (SHW) method was used to measure thermal conductivity of these composites. The results showed that nanoparticle addition leads to substantial enhancement in the thermal conductivity of the composites. The highest thermal conductivity of the measured composites is about 0.27 W/(m•K) of Fe2O3/PW with 3.0 wt% nanoparticles and Al2O3/PW with 5.0 wt% nanoparticles at 15 oC, which higher than that of PW by about 30%. The lowest thermal conductivity of composites is that of Al2O3/PW and ZnO/PW with 1.0 wt% nanoparticles at 60 oC, which higher than that of PW by about 7%.

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Atisme, Yu, Tseng, Chen, Hsu i Chen. "Interface Interactions in Conjugated Polymer Composite with Metal Oxide Nanoparticles". Nanomaterials 9, nr 11 (29.10.2019): 1534. http://dx.doi.org/10.3390/nano9111534.

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This study presents the preparation, characterization, and properties of a new composite containing cerium oxide nanoparticles and a conjugated polymer. CeO2 nanoparticles prepared using the co-precipitation method were dispersed into the conjugated polymer, prepared using the palladium-catalyzed Suzuki–Miyaura cross-coupling reaction. The interface interactions between the two components and the resultant optoelectronic properties of the composite are demonstrated. According to transmission electron microscopy and X-ray absorption spectroscopy, the dispersion of CeO2 nanoparticles in the polymer matrix strongly depends on the CeO2 nanoparticle concentration and results in different degrees of charge transfer. The photo-induced charge transfer and recombination processes were studied using steady-state optical spectroscopy, which shows a significant fluorescence quenching and red shifting in the composite. The higher photo-activity of the composite as compared to the single components was observed and explained. Unexpected room temperature ferromagnetism was observed in both components and all composites, of which the origin was attributed to the topology and defects.

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Rahman, Mohammad Mizanur. "Polyurethane/Zinc Oxide (PU/ZnO) Composite—Synthesis, Protective Property and Application". Polymers 12, nr 7 (11.07.2020): 1535. http://dx.doi.org/10.3390/polym12071535.

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A polyurethane (PU) is a multifunctional polymer prepared by using more than two types of monomers. The unique properties of PU come from monomers, thus broadening the applicability of PU in many different sectors. The properties can be further improved by using many nanoparticles. Different metal oxides as nanoparticles are also widely used in PU materials. ZnO is a widely used inorganic metal oxide nanoparticle for improving polymer properties. In this review article, the techniques to prepare a PU/ZnO composite are reviewed; the key protective properties, such as adhesive strength and self-healing, and applications of PU/ZnO composites are also highlighted. This review also highlights the PU/ZnO composite’s current challenges and future prospects, which will help to broaden the composite practical application by preparing environmentally friendly composites.

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Busko, T. O. "Electron structure of TiO 2 composite films with noble metal nanoparticles". Semiconductor Physics Quantum Electronics and Optoelectronics 17, nr 1 (31.03.2014): 67–74. http://dx.doi.org/10.15407/spqeo17.01.067.

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Zhang, Junyu, i Zhao Wang. "Nanoparticle–Hydrogel Based Sensors: Synthesis and Applications". Catalysts 12, nr 10 (22.09.2022): 1096. http://dx.doi.org/10.3390/catal12101096.

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Hydrogels are hydrophilic three-dimensional (3D) porous polymer networks that can easily stabilize various nanoparticles. Loading noble metal nanoparticles into a 3D network of hydrogels can enhance the synergy of the components. It can also be modified to prepare intelligent materials that can recognize external stimuli. The combination of noble metal nanoparticles and hydrogels to produce modified or new composite materials has attracted considerable attention as to the use of these materials in sensors. However, there is limited review literature on nanoparticle–hydrogel-based sensors. This paper presents the detailed strategies of synthesis and design of the composites, and the latest applications of nanoparticle–hydrogel materials in the sensing field. Finally, the current challenges and future development directions of nanoparticle–hydrogel-based sensors are proposed.

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Li, Zhe Fei, Jian Xie, Lia Stanciu i Yang Ren. "Nanostructured Graphenes and Metal Oxides for Fuel Cell and Battery Applications". Advanced Materials Research 705 (czerwiec 2013): 126–31. http://dx.doi.org/10.4028/www.scientific.net/amr.705.126.

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Graphene/spacer nanoparticle composites were prepared by reducing graphene oxide with hydrazine in the presence of different contents of polyaniline nanoparticles. In-situ cryo-TEM image of GO-spacer solution shows that spacer nanoparticles are anchored on GO sheets. During the reduction, as-adsorbed spacer nanoparticles were sandwiched between layers of graphene. These spacer nanoparticles act as spacers to create gaps between neighboring graphene sheets, resulting in higher surface area. Graphene/spacer nanocomposites exhibited highest specific surface area of 1500 m2/g. Utilizing this composite material, a supercapacitor with specific capacitance of 267 F/g at a current density of 0.1 A/g was achieved.

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Kang, Sang Wook. "Long-Term Stable 1-butyl-3-methylimidazolium Hexafluorophosphate/Ag Metal Composite Membranes for Facilitated Olefin Transport". Membranes 10, nr 8 (18.08.2020): 191. http://dx.doi.org/10.3390/membranes10080191.

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For the preparation of long-term stable ionic liquid/Ag nanoparticles composites, we compared the separation performance of 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM+BF4−)/Ag, and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+PF6−)/Ag composite membranes with time. Separation performance showed that the BMIM+PF6−/Ag metal composite membrane was more stable than the BMIM+BF4−/Ag metal composite membrane for more than 160 h. These differences in long-term stability in BMIM+PF6−/Ag and BMIM+BF4−/Ag metal composite membranes was attributable to the phase separation between ionic liquid and nanoparticles. In particular, the phase separation between ionic liquid and silver nanoparticles was not observed with time in hydrophobic ionic liquid BMIM+PF6−, confirmed by X-ray photoelectron spectroscopy.

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Malaki, Massoud, Wenwu Xu, Ashish Kasar, Pradeep Menezes, Hajo Dieringa, Rajender Varma i Manoj Gupta. "Advanced Metal Matrix Nanocomposites". Metals 9, nr 3 (15.03.2019): 330. http://dx.doi.org/10.3390/met9030330.

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Lightweight high-strength metal matrix nano-composites (MMNCs) can be used in a wide variety of applications, e.g., aerospace, automotive, and biomedical engineering, owing to their sustainability, increased specific strength/stiffness, enhanced elevated temperature strength, improved wear, or corrosion resistance. A metallic matrix, commonly comprising of light aluminum or magnesium alloys, can be significantly strengthened even by very low weight fractions (~1 wt%) of well-dispersed nanoparticles. This review discusses the recent advancements in the fabrication of metal matrix nanocomposites starting with manufacturing routes and different nanoparticles, intricacies of the underlying physics, and the mechanisms of particle dispersion in a particle-metal composite system. Thereafter, the microstructural influences of the nanoparticles on the composite system are outlined and the theory of the strengthening mechanisms is also explained. Finally, microstructural, mechanical, and tribological properties of the selected MMNCs are discussed as well.

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Basak, A. K., A. Pramanik i M. N. Islam. "Failure Mechanisms of Nanoparticle Reinforced Metal Matrix Composite". Advanced Materials Research 774-776 (wrzesień 2013): 548–51. http://dx.doi.org/10.4028/www.scientific.net/amr.774-776.548.

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The quest for the advanced functional material of superior functionality for advanced structure is being driven in various fronts of engineering materials. One of such front is metal matrix composite (MMC) which has already been proven as one of the most productive field in that respect. With the advance of technology, now it is possible to reinforce the MMCs with nanosized particles compared to conventional micron-sized ones. However, the addition of nanoparticle in the MMC to improve its mechanical properties is not unconditional. To achieve positive gain by adding nanoparticles in the MMCs, all the influencing factors should be taken into consideration. The present paper reviews the failure mechanisms of nanoparticles reinforced MMCs in light of its strengthening mechanisms.

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Yatsyshen, Valeriy, Irina Potapova i Vyacheslav Shipaev. "Polaritons in Nanocomposites of Metal Nanoparticles – Dielectric". NBI Technologies, nr 2 (październik 2019): 39–53. http://dx.doi.org/10.15688/nbit.jvolsu.2019.2.7.

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The article studies the main characteristics of surface polaritons in composite nanomaterials. The authors consider composite media such as noble metal nanoparticles randomly distributed in a transparent dielectric matrix and build dispersion curves of polaritons in such nanocomposites. The paper shows calculating optical parameters of the surface polariton for several values of the radius of metal nanoparticles and the nanocomposite filling parameter. The authors also present the calculations of the complex refractive index for polaritons in composites with nanoparticles of different metals. In addition, the authors find the dependences of the real and imaginary parts of the complex refractive index of the nanocomposite on the normalized frequency for membranes with different thicknesses and calculate real and imaginary parts of dielectric constant for waves in several metals. Besides, the article provides an overview of important stages in the study of surface electromagnetic waves. It shows that the variation of the structure materials, size and concentration of nanoparticles opens wide possibilities for controlling the optical properties of composite mediums and their practical application. The considered nanocomposites are artificially created media whose material parameters can be controlled. The first method consists in changing the relative volume of the nanoparticles filling of the dielectric matrix. The second method consists in changing the dielectric constant of the nanocomposite matrix. The authors emphasize that the dielectric constant of the nanocomposite in this case acquires resonant properties in contrast to the permeability of the nanoparticles themselves.

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Pervikov, A. V. "Metal, Metal Composite, and Composited Nanoparticles Obtained by Electrical Explosion of Wires". Nanobiotechnology Reports 16, nr 4 (lipiec 2021): 401–20. http://dx.doi.org/10.1134/s2635167621040091.

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Bui, Quoc Binh, Qing Dong Zhong, Qiong Yu Zhou, Xi Shi i Dan Ji. "Preparation of Epoxy-Organobentonite Nanocomposites Added ZnO-ZrO₂/Al₂O₃-ZrO₂ Nanoparticles and Investigation on their Corrosion Resistance Property in Coating on Q235 Steel". Advanced Materials Research 1033-1034 (październik 2014): 1249–53. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.1249.

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For purpose of synthesis new epoxy coatings to protect the structural steel in sea environment, in this paper, two epoxy-based nanocomposite samples containing low-loading of ZnO-ZrO2/ZrO2-Al2O3 nanoparticles and organobentonite nanoparticles were prepared. Pure epoxy sample and epoxy-based composite added organobentonite nanoparticles were also prepared for comparison. Dispersion of metal oxide particles and organobentonite nanoparticles into epoxy-composites were evaluated by using XRD analyses. Microhardness, adhesion and corrosion resistance over 91 days of immersion in artificial seawater (ASW) solution of new composites were studied by Vickers’ hardness test (HV test), cross-cut test, electrochemical impedance spectroscopy (EIS) and polarization curves, respectively. Results showed that combined use of low-loading fillers had a positive effect on the organobentonite exfoliation behavior in resulting epoxy-based nanocomposites. Hardness, adhesion of two novel composites increased in comparison to pure epoxy even though with epoxy-based composite added organobentonite only. Results also showed that nanoparticle fillers could significantly improve the corrosion resistance of the coated steel, with ZnO-ZrO2-organobentonite fillers being the best.

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Nandakumar, A., i D. Dinakaran. "Effect of Nanoparticles in Reinforced Metal Matrix Composite on the Machinability Characteristics - A Review". Applied Mechanics and Materials 813-814 (listopad 2015): 625–28. http://dx.doi.org/10.4028/www.scientific.net/amm.813-814.625.

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Metal Matrix nanoComposites (MMNC) refer to materials consisting of a ductile metal or alloy matrix in which some nanosized reinforcement materials is implanted. These materials combine metal and ceramic features, i.e., ductility and toughness with high strength. Thus, metal matrix nanocomposites are suitable for production of materials with high strength in shear/compression processes and high service temperature capabilities. Both Metal Matrix Composite (MMC) and Ceramic Matrix Composites (CMC) with Carbon nanoTubes (CNT) nanocomposites hold promise, but also pose challenges for real success. In the present paper deals an inclusive review of literature in effect of nanoparticles in reinforced metal matrix composites on the machinability characteristics of the composite materials.

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Venkatesh, R., Vaddi Seshagiri Rao i Sathish Rengarajan. "A Comprehensive Study of Aluminium Based Metal Matrix Composite Reinforced with Hybrid Nanoparticles". METALLOFIZIKA I NOVEISHIE TEKHNOLOGII 41, nr 4 (9.07.2019): 481–500. http://dx.doi.org/10.15407/mfint.41.04.0481.

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Panda, Atanu, Euisoo Kim, Yong Choi, Jihyun Lee, Sada Venkateswarlu i Minyoung Yoon. "Phase Controlled Synthesis of Pt Doped Co Nanoparticle Composites Using a Metal-Organic Framework for Fischer–Tropsch Catalysis". Catalysts 9, nr 2 (5.02.2019): 156. http://dx.doi.org/10.3390/catal9020156.

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Recently, metal nanoparticles embedded in porous carbon composite materials have been playing a significant role in a variety of fields as catalyst supports, sensors, absorbents, and in energy storage. Porous carbon composite materials can be prepared using various synthetic methods; recent efforts provide a facile way to prepare the composites from metal-organic frameworks (MOFs) by pyrolysis. However, it is usually difficult to control the phase of metal or metal oxides during the synthetic process. Among many types of MOF, recently, cobalt-based MOFs have attracted attention due to their unique catalytic and magnetic properties. Herein, we report the synthesis of a Pt doped cobalt based MOF, which is subsequently converted into cobalt nanoparticle-embedded porous carbon composites (Pt@Co/C) via pyrolysis. Interestingly, the phase of the cobalt metal nanoparticles (face centered cubic (FCC) or hexagonal closest packing (HCP)) can be controlled by tuning the synthetic conditions, including the temperature, duration time, and dosage of the reducing agent (NaBH4). The Pt doped Co/C was characterized using various techniques including PXRD (powder X-ray diffraction), XPS (X-ray photoelectron spectroscopy), gas sorption analysis, TEM (transmission electron microscopy), and SEM (scanning electron microscopy). The composite was applied as a phase transfer catalyst (PTC). The Fischer-Tropsch catalytic activity of the Pt@Co/C (10:1:2.4) composite shows 35% CO conversion under a very low pressure of syngas (1 MPa). This is one of the best reported conversion rates at low pressure. The 35% CO conversion leads to the generation of various hydrocarbons (C1, C2–C4, C5, and waxes). This catalyst may also prove useful for energy and environmental applications.

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Vasil’kov, Alexander, Margarita Rubina, Alexander Naumkin, Mikhail Buzin, Pavel Dorovatovskii, Georgy Peters i Yan Zubavichus. "Cellulose-Based Hydrogels and Aerogels Embedded with Silver Nanoparticles: Preparation and Characterization". Gels 7, nr 3 (2.07.2021): 82. http://dx.doi.org/10.3390/gels7030082.

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The paper presents the preparation and characterization of novel composite materials based on microcrystalline cellulose (MCC) with silver nanoparticles (Ag NPs) in powder and gel forms. We use a promising synthetic conception to form the novel composite biomaterials. At first MCC was modified with colloidal solution of Ag NPs in isopropyl alcohol prepared via metal vapor synthesis. Then Ag-containing MCC powder was used as precursor for further preparation of the gels. The hydrogels were prepared by dissolving pristine MCC and MCC-based composite at low temperatures in aqueous alkali solution and gelation at elevated temperature. To prepare aerogels the drying in supercritical carbon dioxide was implemented. The as-prepared cellulose composites were characterized in terms of morphology, structure, and phase composition. Since many functional properties, including biological activity, in metal-composites are determined by the nature of the metal-to-polymer matrix interaction, the electronic state of the metal was carefully studied. The studied cellulose-based materials containing biologically active Ag NPs may be of interest for use as wound healing or water-purification materials.

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Takashima, Yohei, Seiko Tetsusashi, Shintaro Tanaka, Takaaki Tsuruoka i Kensuke Akamatsu. "Direct generation of polypyrrole-coated palladium nanoparticles inside a metal-organic framework for a semihydrogenation catalyst". RSC Advances 13, nr 11 (2023): 7464–67. http://dx.doi.org/10.1039/d2ra08190c.

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Polypyrrole-coated palladium nanoparticles could be directly generated inside a metal–organic frameworks. The resulting MOF composites exhibited higher semihydrogenation capability than the analog composite without polypyrrole coating.

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Rostami, Ghassem, Mahmoud Shahabadi, Ali Afzali-Kusha i Ali Rostami. "EIT based tunable metal composite spherical nanoparticles". Photonics and Nanostructures - Fundamentals and Applications 10, nr 1 (styczeń 2012): 102–11. http://dx.doi.org/10.1016/j.photonics.2011.08.001.

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Jarju, Jenni J., Ana M. Lavender, Begoña Espiña, Vanesa Romero i Laura M. Salonen. "Covalent Organic Framework Composites: Synthesis and Analytical Applications". Molecules 25, nr 22 (18.11.2020): 5404. http://dx.doi.org/10.3390/molecules25225404.

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In the recent years, composite materials containing covalent organic frameworks (COFs) have raised increasing interest for analytical applications. To date, various synthesis techniques have emerged that allow for the preparation of crystalline and porous COF composites with various materials. Herein, we summarize the most common methods used to gain access to crystalline COF composites with magnetic nanoparticles, other oxide materials, graphene and graphene oxide, and metal nanoparticles. Additionally, some examples of stainless steel, polymer, and metal-organic framework composites are presented. Thereafter, we discuss the use of these composites for chromatographic separation, environmental remediation, and sensing.

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Li, Shan Shan, Ying Nan Dong, You Ning Xu, Bing Li i Mei Ling Tang. "Photochemical Synthesis of Pd Core @ Pt Shell Nanoparticles in Polyethylene Glycol (PEG) Solution System". Applied Mechanics and Materials 535 (luty 2014): 753–57. http://dx.doi.org/10.4028/www.scientific.net/amm.535.753.

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In the sodium citrate solution systems containing double metal ions with different Pd-Pt molar ratios and single Pt (IV) ions, Pd Core @ Pt Shell nanoparticles were synthesized by the photochemical coreduction and Pd seed method, respectively. By means of characterization of TEM, the change regularity of the composite nanoparticle sizes was studied in both preparation methods. The surface chemical state of the composite nanoparticles and their structure were analyzed by X-ray photoelectron spectroscopy (XPS), confirming that Pd @ Pt nanoparticles formed are core-shell structure. Keywords: Pd Core @ Pt Shell; Photochemical; Simultaneous reduction; Seeding growth

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Yousefian, Razieh, Esmaeil Emadoddin i Sadreddin Baharnezhad. "Manufacturing of the Aluminum Metal-Matrix Composite Reinforced with Micro- and Nanoparticles of Tio2 Through Accumulative Roll Bonding Process (Arb)". REVIEWS ON ADVANCED MATERIALS SCIENCE 55, nr 1 (1.04.2018): 1–11. http://dx.doi.org/10.1515/rams-2018-0022.

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Abstract The aluminum metal-matrix composites reinforced with the micro- and nanoparticles of TiO2 were manufactured in the form of sheets through the accumulative roll bonding (ARB) process which has been lately considered as a novel method under an intense plastic deformation so as to produce particulate-reinforced metal-matrix composites. Themicrostructural examinations via optic microscopy and scanning electron microscopy (SEM) depict that the distribution of TiO2 particles in the aluminum matrix is almost uniform and also the dispersion of the microparticles of TiO2 is more homogeneous than that of the nanoparticles one. Furthermore, the tensile tests demonstrate the noteworthy enhancements in the tensile strengths of the composites, compared to the Al 1100 as the virgin metal, however, by attenuating the size of the particles, i.e. from micron to nano, the composite tensile strengths are augmented. The fractographic analysis of the fracture surfaces revealed that the fracture mode in the ARB-processed Al/TiO2 composite is the shear ductile rupture type.

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Kumar, Raj, Dinesh Shringi i Kedar Narayan Bairwa. "Numerical validation of thermal conductivity of Al6061 based hybrid nano metal matrix composite filled with nanoparticles of Ni and Cr". Materials Research Express 8, nr 11 (1.11.2021): 115011. http://dx.doi.org/10.1088/2053-1591/ac3692.

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Abstract Aluminum composite matrix materials are regarded as the most popular type of composite materials. Metal matrix composites made of aluminum have better mechanical and thermal properties, including a higher strength-to-weight ratio, tensile strength, hardness, and a low coefficient of thermal expansion. In various types of applications viz, automobile, aviation, the thermal characterization of aluminum metal matrix composites has increased. Thermal conductivity as a function of temperature, thermal diffusivity, and the thermal gradient is one of the essential thermal characteristics of aluminum metal matrix composites needed to understand the material’s behavior. The current work evaluated thermal conductivity as a product of thermal diffusivity, density, and specific heat for Al6061/Ni/Cr hybrid nano metal matrix composites from 50 °C to 300 °C. Al6061 based metal matrix composite reinforced with varying wt.% of Ni and Cr nanoparticles whereas fixed wt.% of graphene and Mg added to improve thermal conductivity, self-lubrication, and wettability. Thermal diffusivity, specific heat, and density were evaluated using laser flash apparatus (LFA 447), differential scanning calorimetry (DSC), and Archimedes principle, respectively. Results revealed that the thermal conductivity of fabricated composites increases with Ni, Cr, Mg, and graphene nanoparticles. With further expansion of reinforced particles of Ni and Cr, the thermal conductivity decreases. Finite element analysis (FEA) has been conducted to determine the thermal gradient and thermal flux using experimental values such as density, thermal conductivity, specific heat, and enthalpy at various temperature ranges to validate the experimental results.

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Pan, Zhi Long, Jia Ting Chen, Shi Liang Ao i Jian Ping Jia. "Synthesis and Dielectric Behavior of a New Two-Phase Percolative BaTiO₃-Cu/Polyimide Composite". Applied Mechanics and Materials 670-671 (październik 2014): 263–66. http://dx.doi.org/10.4028/www.scientific.net/amm.670-671.263.

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The chemical reduction method was used to deposit copper nanoparticles (about 20nm) on the surface of the barium titanate (BT, r=50nm). Then the dielectric properties and the mechanism of BaTiO3-Cu/polyimide composite were studied. The results showed that the effective dielectric permittivity of the composite with 60 wt% of BT-Cu (less than 13.00 wt% of copper) fillers was greater than 120, and the dielectric loss of which was lower than 0.025. Due to very low dielectric loss, so this composite was a two-phase composite material, different from the three-phase composite (metal-ceramics-poly). It was concluded that copper nanoparticles were deposited on the surface of the BT nanoparticles by chemical bond. Owing to good dielectric properties of as-prepared composite, such new two-phase composites had a potential to become the most important ferroelectric material.

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Narayan, Neel, Ashokkumar Meiyazhagan i Robert Vajtai. "Metal Nanoparticles as Green Catalysts". Materials 12, nr 21 (2.11.2019): 3602. http://dx.doi.org/10.3390/ma12213602.

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Nanoparticles play a significant role in various fields ranging from electronics to composite materials development. Among them, metal nanoparticles have attracted much attention in recent decades due to their high surface area, selectivity, tunable morphologies, and remarkable catalytic activity. In this review, we discuss various possibilities for the synthesis of different metal nanoparticles; specifically, we address some of the green synthesis approaches. In the second part of the paper, we review the catalytic performance of the most commonly used metal nanoparticles and we explore a few roadblocks to the commercialization of the developed metal nanoparticles as efficient catalysts.

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Joshi, Hira, Siddharth Choudhary i S. Annapoorni. "Composite Nanostructures for Enhanced Plasmonics". Materials Science Forum 950 (kwiecień 2019): 165–69. http://dx.doi.org/10.4028/www.scientific.net/msf.950.165.

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Enhancement in plasmonic response of metal nanoparticles in the form of metal/metal oxide nanocomposites is very interesting from both the theoretical understanding and application. Metal based oxide/Ag nanocomposites were synthesized by polyol process. Metal oxide nanoparticles present in nanocomposites as core and noble metal as a shell are of interest in investigation of plasmonic behavior of noble metals and sensing application. Cobalt ferrite (CoFe2O4) and ZnO were used as oxide core in the form of spherical and rod nanostructures respectively. Presence of Ag was confirmed by XRD and SEM analysis. In this paper we summarize the synthesis and characterization of plasmonic properties of composite nanostructures. Optical absorption studies performed on CoFe2O4@Ag and ZnO@Ag exhibit sharp plasmonic resonance but shifted towards lower wavelength (blue shift). An attempt has been made to explain this shift using the Mie scattering calculations based on size variation and change in the dielectric of the surrounding medium.

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Bastwros, Mina M. H., i Gap Yong Kim. "Fabrication of Metal Laminate Composites with Interface Reinforcement by Semi-Solid Sintering". Solid State Phenomena 256 (wrzesień 2016): 205–15. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.205.

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Semi-solid sintering technique has been introduced to alter the interfaces of a metal laminate composite material. A thin layer of reinforcement nanoparticles was applied on substrate metallic sheets using an ultrasonic spray deposition method. The sheets were then stacked, pressed, and sintered in the semi-solid regime of the metallic sheet. The liquid phase present in the matrix material penetrates and diffuses into the nanoparticle layer during consolidation and helps to form a gradual, nanostructured interface. Aluminum (Al6061) and magnesium (AZ31) alloy foils were used as the matrix sheets while various species of reinforcement particles were investigated, including silicon carbide (SiC), silicon (Si), and a mix of Si+SiC. Multilayered metal composites with nanostructured interfaces were successfully consolidated and were evaluated by performing a three-point bend test. AZ31 composites reinforced with SiC nanoparticle interface showed an improvement of 49% in flexural yield strength when compared with a reference sample without such interfaces.

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Shi, Shih-Chen, i Jason Hsiao Chun Yang. "Preparation of stable biopolymer composite suspension with metal/metal-oxide nanoparticles". Modern Physics Letters B 34, nr 07n09 (18.03.2020): 2040028. http://dx.doi.org/10.1142/s021798492040028x.

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Hydroxypropyl methylcellulose (HPMC) is a kind of biopolymer that is biodegradable, environmentally friendly and possesses exceptional mechanical and tribological properties. Therefore, it could be used as a suitable alternative to plastic. However, HPMC deforms easily when subjected to loads, causing higher real contact area and adhesive force between HPMC and grinding counter. Therefore, HPMC films are easily damaged because of adhesive wear, which negatively affects wear resistance. Hence, nanoparticles (NPs) of Al, Cu, Al2O3 and CuO have been used as fillers to increase the wear resistance of the HPMC composite films. The uniform dispersion of NPs in the suspension is the most important factor, which is greatly related to the wear resistance after film formation. Nanosuspensions with various dispersant concentrations were prepared, and mixed with the HPMC solution to prepare composite solutions and composite films. The results showed that Span 80 could provide steric stabilization, and that it dispersed the NPs effectively in suspension. After mixing the suspension with the HPMC solution, the solution became more stable.

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Zaiemyekeh, Zahra, Gholamhossein Liaghat i Muhammad K. Khan. "Effect of Al2O3 nanoparticles on the mechanical behaviour of aluminium-based metal matrix composite synthesized via powder metallurgy". Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 235, nr 10 (22.09.2021): 2340–55. http://dx.doi.org/10.1177/14644207211033626.

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The effects of variation in aluminium oxide nanoparticles in aluminium-based metal matrix composite on the compressive and sliding wear deformation have been investigated. The compressive and sliding wear resistance of the composite increase significantly with the addition of nanoparticles in the matrix. The 5% aluminium oxide nanoparticles in the composite were found to be the optimal weight fraction of added nanoparticles that produced higher static yield strength, hardness, scratch resistance and lower material loss in wear in the composite. The addition of nanoparticles, beyond 5% weight fraction, in the matrix showed adverse effects in the performance of the composite due to its higher brittleness. The effects on wear properties of the composite with added nanoparticles beyond optimal weight fraction were more detrimental than those with lower weight fraction of nanoparticles.

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Kovtun, V., V. Pasovets i T. Pieczonka. "Investigation of Structure and Physico-Mechanical Properties of Composite Materials Based on Copper - Carbon Nanoparticles Powder Systems". Archives of Metallurgy and Materials 60, nr 1 (1.04.2015): 51–55. http://dx.doi.org/10.1515/amm-2015-0008.

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Abstract Physico-mechanical and structural properties of electrocontact sintered copper matrix- carbon nanoparticles composite powder materials are presented. Scanning electron microscopy revealed the influence of preliminary mechanical activation of the powder system on distribution of carbon nanoparticles in the metal matrix. Mechanical activation ensures mechanical bonding of nanoparticles to the surface of metal particles, thus giving a possibility for manufacture of a composite with high physico-mechanical properties.

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Nikoshvili, Linda Z., Boris B. Tikhonov, Pavel E. Ivanov, Polina Y. Stadolnikova, Mikhail G. Sulman i Valentina G. Matveeva. "Recent Progress in Chitosan-Containing Composite Materials for Sustainable Approaches to Adsorption and Catalysis". Catalysts 13, nr 2 (7.02.2023): 367. http://dx.doi.org/10.3390/catal13020367.

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In recent years, composite materials including organic–inorganic systems have drawn special attention due to their enhanced properties such as adsorbents and heterogeneous catalysts. At the same time, large-scale production of environmentally benign functionalized biopolymers, such as chitosan (CS), allows for constantly developing new materials, since CS reveals remarkable properties as a stabilizing agent for metal-containing compounds and enzymes and as an adsorbent of organic molecules. This review is focused on CS-based materials and on the composite systems including CS–oxide and CS–metal composites in particular for application as adsorbents and supports for catalytically active metal nanoparticles and enzymes.

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Gouda, M., AA Hebeish i AI Aljaafari. "New route for development of electromagnetic shielding based on cellulosic nanofibers". Journal of Industrial Textiles 46, nr 8 (21.01.2016): 1598–615. http://dx.doi.org/10.1177/1528083715627166.

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A radically new innovation was established for development of electromagnetic interference shielding. The innovation emphasis synthesis of carboxymethyl cellulose (CMC), carboxymethyl cellulose composite containing different metal nanoparticles (CMC-MNPs), and carboxymethyl cellulose nanofiber mat (CMC-NF) and carboxymethyl cellulose containing metal nanofiber mat (CMC-MNPs nanofiber mat) by electrospinning technique. Metal nanoparticles used include copper nanoparticles, iron nanoparticles, zinc nanoparticles, cadmium nanoparticles, and cobalt nanoparticles. Synthesized CMC–MNPs were characterized by using scanning electron microscopy coupled with high-energy dispersive X-ray and UV–visible spectroscopy that was used for confirmation of nanoparticles formation. The scanning electron microscopy images clearly showed regular flat shape with semiporous surface. All metal nanoparticles were well distributed inside the backbone of the cellulose without aggregation. The average particle diameter was 29–39 nm for zinc nanoparticles, 29–33 nm for cadmium nanoparticles, 25–33 nm for cobalt nanoparticles, 23–27 nm for copper nanoparticles, and 22–26 nm for iron nanoparticles. Electrospun carboxymethyl cellulose and CMC–MNPs nanofiber mats were synthesized by electrospinning technique and characterized using scanning electron microscopy, energy dispersive X-ray, and transmission electron microscopy. Scanning electron microscopy images of electrospun carboxymethyl cellulose and CMC–MNPs nanofibers reveal smooth and uniformly distributed nanofibers without bead formation with average fiber diameters in the range of 300–450 nm. Moreover, the diameters of electrospun carboxymethyl cellulose nanofiber mat were not affected by the presence of metal nanoparticles. Metal nanoparticles’ content inside the electrospun CMC–MNPs nanofibers was investigated by using atomic absorption spectroscopy. Electromagnetic interference shielding of electrospun carboxymethyl cellulose and CMC–MNPs nanofiber mats was evaluated. Data showed that the EMI-SE was increased in presence of metal nanoparticles and depending on both the metal nanoparticle contents and the electrical conductivity of metal nanoparticles.

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Fujioka, Daiki, Shingo Ikeda, Kensuke Akamatsu, Hidemi Nawafune i Kazuo Kojima. "Preparation of Ni nanoparticles by liquid-phase reduction to fabricate metal nanoparticle–polyimide composite films". RSC Advances 9, nr 12 (2019): 6438–43. http://dx.doi.org/10.1039/c9ra00182d.

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Nickel-nanoparticle-containing polyimide composite films were prepared by liquid-phase reduction of Ni²⁺ ions with potassium borohydride (KBH₄). This preparation method could be repeated to increase the number of the nanoparticles in the films.

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Tang, Luping, Chen Liao, Yingqing Guo i Yangyang Zhang. "Controllable Preparation of Ag-SiO2 Composite Nanoparticles and Their Applications in Fluorescence Enhancement". Materials 16, nr 1 (26.12.2022): 201. http://dx.doi.org/10.3390/ma16010201.

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Metal nanoparticles have attracted a great deal of interest due to their unique properties of surface plasmon resonance. Metal nanoparticles can enhance the fluorescence emission intensity of quantum dots (QDs) through the local surface plasmon resonance effect, which is mainly determined by the distance between them. Therefore, it is very important to achieve controllable distance between metal and QDs, and study fluorescence enhancement. In this work, the controllable adjustment of the distance between metal nanoparticles and QDs was successfully realized by controlling the thickness of the SiO2 shell of Ag@SiO2 nanoparticles. Firstly, Ag nanoparticles with uniform size distribution and relatively high concentration were prepared, and then the thickness of the SiO2 shell was controlled by controlling the amount of tetra-ethyl orthosilicate (TEOS) in the hydrolysis of TEOS reaction. (3-aminopropyl) triethoxysilane (APS) was used to connect CdS/ZnS QDs with Ag@SiO2 nanoparticles to form Ag@SiO2@CdS/ZnS QD composite nanoparticles. The fluorescence spectra shows that the fluorescence intensity of the Ag@SiO2@CdS/ZnS QD composite nanoparticles is significantly enhanced. Photoexcitation spectra and fluorescence spectra of CdS/ZnS QD and Ag@SiO2@CdS/ZnS QD composite nanoparticles, measured under different energy excitation conditions, indicate that the existence of Ag nanoparticles can enhance the fluorescence intensity of CdS/ZnS QDs. Finally, a further physical mechanism of fluorescence enhancement is revealed.

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Ahmad, Tahir, i Othman Mamat. "Characterization and Properties of Iron/Silica-Sand-Nanoparticle Composites". Defect and Diffusion Forum 316-317 (maj 2011): 97–106. http://dx.doi.org/10.4028/www.scientific.net/ddf.316-317.97.

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Metal matrix-particulate composites fabricated by using powder metallurgy possess a higher dislocation density, a small sub-grain size and limited segregation of particles, which, when combined, result in superior mechanical properties. The present study aims to develop iron based silica sand nanoparticles composites with improved mechanical properties. An iron based silica sand nanoparticles composite with 5, 10, 15 and 20 wt.% of nanoparticles silica sand were developed through powder metallurgy technique. It was observed that by addition of silica sand nanoparticles with 20 wt.% increased the hardness up to 95HRB and tensile strength up to 690MPa. Sintered densities and electrical conductivity of the composites were improved with an optimum value of 15 wt.% silica sand nanoparticles. Proposed mechanism is due to diffusion of silica sand nanoparticles into porous sites of the composites.

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Dhapte, Vividha, Shivajirao Kadam, Varsha Pokharkar, Pawan K. Khanna i Vishwas Dhapte. "Versatile SiO2 Nanoparticles@Polymer Composites with Pragmatic Properties". ISRN Inorganic Chemistry 2014 (29.01.2014): 1–8. http://dx.doi.org/10.1155/2014/170919.

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In the present work, we report the fabrication of silica nanoparticles embedded polymeric (SiO2 nanoparticles@polymer) composite films for numerous traits like texture, folding endurance, crystallinity, size, thermal behavior, spectral analysis, and bioactivity. Significant facets of bulky, inert, inorganic materials are known to burgeon out due to the high surface area of nanosized particles. Nature and proportion of silica nanoparticles as well as polymers exhibited remarkable impact on the fabrication and quality of casted films. Hydrophilic silica nanoparticulate-PVA films depicted better mechanical properties like thermal plus photo stability. Hydrophobic silica nanoparticulate-PMMA films showed qualities of a robust, active, thermostable, antimicrobial material that could resist extreme storage and processing conditions. Overall, these metal oxide nanoparticle-polymer composite films possess qualities reflecting their potential in food, pharmaceutical, and cosmetic industry.

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Hussain, Saghir, Noorulain Khakwani, Yasir Faiz, Sonia Zulfiqar, Zahid Shafiq, Faisal Faiz, Abeer Elhakem i in. "Green Production and Interaction of Carboxylated CNTs/Biogenic ZnO Composite for Antibacterial Activity". Bioengineering 9, nr 9 (4.09.2022): 437. http://dx.doi.org/10.3390/bioengineering9090437.

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Using biomolecule-rich plant extracts, the conversion of metal ions to metal oxide nanoparticles via abiogenic approach is highly intriguing, environmentally friendly, and quick. The inherent inclination of plant extracts function as capping agents in the insitu synthesis. In this study, biogenic zinc oxide nanoparticles (ZnO−NPs) were synthesized using an aqueous leaf extract from Moringaoleifera. The ZnO−NPs were then mixed with carboxylated carbon nanotubes (CNTs) to create a carboxylated CNTs/biogenic ZnO composite using asol–gel method. The CNTs/ZnO composite displayed 18 mm, 16 mm, and 17 mm zones of inhibition (ZOI) against Bacillus cereus, Pseudomonas aeruginosa, and Escherichia coli, respectively. In contrast with ZnO−NPs, the produced carboxylated CNTs/ZnO composite demonstrated a 13 percent elevation in ZOI as antibacterial activity against Bacillus cereus ATCC 19659, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853. The characterization of ZnO−NPs and the carboxylated CNTs/ZnO composite were performed via FTIR, UV/Vis spectroscopy, SEM, and XRD. The XRD pattern depicted a nano−sized crystalline structure (Wurtzite) of ZnO−NPs and a carboxylated CNTs/ZnO composite. The current work comprehends a valuable green technique for killing pathogenic bacteria, and gives fresh insights into the manufacture of metal oxide composites for future research.

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Pierini, Filippo, Massimiliano Lanzi, Paweł Nakielski i Tomasz Aleksander Kowalewski. "Electrospun Polyaniline-Based Composite Nanofibers: Tuning the Electrical Conductivity by Tailoring the Structure of Thiol-Protected Metal Nanoparticles". Journal of Nanomaterials 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/6142140.

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Composite nanofibers made of a polyaniline-based polymer blend and different thiol-capped metal nanoparticles were prepared using ex situ synthesis and electrospinning technique. The effects of the nanoparticle composition and chemical structure on the electrical properties of the nanocomposites were investigated. This study confirmed that Brust’s procedure is an effective method for the synthesis of sub-10 nm silver, gold, and silver-gold alloy nanoparticles protected with different types of thiols. Electron microscopy results demonstrated that electrospinning is a valuable technique for the production of composite nanofibers with similar morphology and revealed that nanofillers are well-dispersed into the polymer matrix. X-ray diffraction tests proved the lack of a significant influence of the nanoparticle chemical structure on the polyaniline chain arrangement. However, the introduction of conductive nanofillers in the polymer matrix influences the charge transport noticeably improving electrical conductivity. The enhancement of electrical properties is mediated by the nanoparticle capping layer structure. The metal nanoparticle core composition is a key parameter, which exerted a significant influence on the conductivity of the nanocomposites. These results prove that the proposed method can be used to tune the electrical properties of nanocomposites.

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Zhang, Xiaojun, Man Wang, Manhong Li, Minglu Zhang i Chengwei Zhang. "Fabrication of Macroporous Nafion Membrane from Silica Crystal for Ionic Polymer-Metal Composite Actuator". Processes 8, nr 11 (31.10.2020): 1389. http://dx.doi.org/10.3390/pr8111389.

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Nafion membrane with macropores is synthesized from silica crystal and composited with Pt nanoparticles to fabricate macroporous ionic polymer-metal composite (M-IPMC) actuator. M-IPMC shows highly dispersed small Pt nanoparticles on the porous walls of Nafion membrane. After the electromechanical performance test, M-IPMC actuator demonstrates a maximum displacement output of 19.8 mm and a maximum blocking force of 8.1 mN, far better than that of IPMC actuator without macroporous structure (9.6 mm and 2.8 mN) at low voltages (5.8–7.0 V). The good electromechanical performance can be attributed to interconnected macropores that can improve the charge transport during the actuation process and can allow the Pt nanoparticles to firmly adsorb, leading to a good electromechanical property.

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Nechifor, Gheorghe, Florentina Mihaela Păncescu, Alexandra Raluca Grosu, Paul Constantin Albu, Ovidiu Oprea, Szidonia-Katalin Tanczos, Constantin Bungău, Vlad-Alexandru Grosu, Andreia Pîrțac i Aurelia Cristina Nechifor. "Osmium Nanoparticles-Polypropylene Hollow Fiber Membranes Applied in Redox Processes". Nanomaterials 11, nr 10 (27.09.2021): 2526. http://dx.doi.org/10.3390/nano11102526.

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Composite membranes play a very important role in the separation, concentration, and purification processes, but especially in membrane reactors and membrane bioreactors. The development of composite membranes has gained momentum especially through the involvement of various nanoparticles, polymeric, oxide, or metal, that have contributed to increasing their reactivity and selectivity. This paper presents the preparation and characterization of an active metal nanoparticle-support polymer type composite membrane, based on osmium nanoparticles obtained in situ on a polypropylene hollow fiber membrane. Osmium nanoparticles are generated from a solution of osmium tetroxide in tert-butyl alcohol by reduction with molecular hydrogen in a contactor with a polypropylene membrane. The composite osmium-polypropylene hollow fiber obtained membranes (Os-PPM) were characterized from the morphological and structural points of view: scanning electron microscopy (SEM), high resolution SEM (HR-SEM), energy dispersive spectroscopy analysis (EDAX), X-ray diffraction analysis (XRD), Fourier transform Infrared (FTIR) spectroscopy, thermal gravimetric analysis, and differential scanning calorimetry (TGA, DSC). The process performance was tested in a redox process of p-nitrophenol and 10-undecylenic (10-undecenoic) acid, as a target substance of biological or biomedical interest, in solutions of lower aliphatic alcohols in a membrane contactor with a prepared composite membrane. The characteristics of osmium nanoparticles-polypropylene hollow fiber membranes open the way to biological and biotechnological applications. These membranes do not contaminate the working environment, operate at relatively low temperatures, provide a large contact area between reactants, allow successive oxidation and reduction operations in the same module, and help to recover the reaction mass by ultrafiltration. The results obtained show that the osmium-polypropylene composite membrane allows the reduction of p-nitrophenol or the oxidation of 10-undecylenic acid, the conversion depending on the concentration in the lower aliphatic alcohol, the nature of the lower aliphatic alcohol, and the oxidant or reducing flow through the membrane contactor.

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Akmaz, Solmaz, Esra Dilaver Adıgüzel, Muzaffer Yasar i Oray Erguven. "The Effect of Ag Content of the Chitosan-Silver Nanoparticle Composite Material on the Structure and Antibacterial Activity". Advances in Materials Science and Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/690918.

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The aim of this study is to investigate the antibacterial properties and characterization of chitosan-silver nanoparticle composite materials. Chitosan-silver nanoparticle composite material was synthesized by adding AgNO3and NaOH solutions to chitosan solution at 95°C. Different concentrations (0,02 M, 0,04 M, and 0,06 M) of AgNO3were used for synthesis. Chitosan-silver nanoparticle composite materials were characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), ultraviolet (UV) spectrophotometer, and Fourier transform infrared (FTIR) spectrometer techniques.Escherichia coli,Acinetobacter baumannii,Staphylococcus aureus,Enterococcus faecalis,Pseudomonas aeruginosa, andStreptococcus pneumoniaewere used to test the bactericidal efficiency of synthesized chitosan-Ag nanoparticle composite materials. The biological activity was determined by the minimum bacterial concentration (MBC) of the materials. Antibacterial effect of chitosan-silver nanoparticle materials was increased by increasing Ag amount of the composite materials. The presence of small amount of metal nanoparticles in the composite was enough to significantly enhance antibacterial activity as compared with pure chitosan.

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Weeks, Nathan J., Bradley Martin, Enrique Gazmin i Scott T. Iacono. "Thermal Data of Perfluorinated Carboxylic Acid Functionalized Aluminum Nanoparticles". Data 8, nr 1 (23.12.2022): 5. http://dx.doi.org/10.3390/data8010005.

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Improving the performance of composite energetic materials comprised of a solid metal fuel and a source of oxidizer (known as thermites) has long been pursued as thermites for pyrolant flares and rocket propellants. The performance of thermites, involving aluminum as the fuel, can be dramatically improved by utilizing nanometer-sized aluminum particles (nAl) leading to vastly higher reaction velocities, owing to the high surface area of nAl. Despite the benefits of the increased surface area, there are still several problems inherent to nanoscale reactants including particle aggregation, and higher viscosity composited materials. The higher viscosity of nAl composites is cumbersome for processing with inert polymer binder formulations, especially at the high mass loadings of metal fuel necessary for industry standards. In order to improve the viscosity of high mass loaded nAl energetics, the surface of the nAl was passivated with covalently bound monolayers of perfluorinated carboxylic acids (PFCAs) utilizing a novel fluorinated solvent washing technique. This work also details the quantitative binding of these monolayers using infrared spectroscopy, in addition to the energetic output from calorimetric and thermogravimetric analysis.

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Bahramnia, Hamed, Hamidreza Mohammadian Semnani, Ali Habibolahzadeh i Hassan Abdoos. "Epoxy/polyurethane nanocomposite coatings for anti-erosion/wear applications: A review". Journal of Composite Materials 54, nr 22 (12.03.2020): 3189–203. http://dx.doi.org/10.1177/0021998320908299.

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Offshore pipelines are vulnerable against erosion/wear deterioration mechanisms that can be controlled through the use of proper surface coatings, such as polymer matrix nano-composite (PMNC) coatings that are well-known for their ease of production, availability and applicability. Epoxy, as a versatile rigid and brittle resin and polyurethane with proper chemical/mechanical properties, are potential candidates to make the matrix of these composites. A combination of these polymers can also enhance the mechanical behaviors, glass transition temperature and flexibility. In addition, the desired coating characteristics, such as adhesion to metal substrate, mechanical properties, erosion/wear resistivity and UV absorbance, can be further improved through the addition of appropriate nanoparticles within the polymer matrix. Especially, nanoparticles can improve the erosion/wear resistance of polymers because of establishing high strength bonds between the polymer chains and the reinforcements besides enhancing other required properties. The present work is a review on PMNC coatings that contain epoxy, polyurethane or EP/polyurethane as a polymer matrix along with the details of the nanoparticle reinforcements, such as alumina, silica, titanium oxide, zinc oxide, clay and carbon-based materials. The effect of these nanoparticles on the properties of composite coatings has also been investigated.

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Zhang, Liangmin. "Optical Conduction Resonance in Self-Assembled Metal Nanoparticle Array-Dielectric Thin Films". Journal of Nanomaterials 2018 (10.12.2018): 1–9. http://dx.doi.org/10.1155/2018/8540805.

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Optical conduction resonance- (OCR-) enhanced third-order optical nonlinearity of two dimensional (2D) periodic gold nanoparticle array-dielectric thin films has been investigated. The third-order optical susceptibility of periodic gold nanoparticle array embedded in silica thin film shows ~104 enhancement comparing to gold nanoparticle colloids. The 2D gold nanoparticle arrays were synthesized by using the electrostatic self-assembly (ESA) technique. During the fabrication process, the positively or negatively functionalized gold nanoparticles are automatically self-aligned to establish a 2D array with a very small interparticle spacing due to the polymer shell on the metal particles. Then, a monolayer of silica can be coated on the top of the 2D metal nanoparticle array. This type of 2D gold nanoparticle array-dielectric thin films has high volume fraction of gold nanoparticles. According to the extended Maxwell-Garnett theory, this kind of films can exhibit OCR. The OCR frequency can be tuned from visible to mid-infrared by controlling the gold nanoparticle volume fraction. During OCR, the real part of the composite dielectric constant is zero to make the induced electromagnetic waves in gold nanoparticles to couple effectively within the film. The open-aperture z-scan technique is used to measure the nonlinear optical properties of the ESA films.

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Konopka, Katarzyna. "Particle-Reinforced Ceramic Matrix Composites—Selected Examples". Journal of Composites Science 6, nr 6 (19.06.2022): 178. http://dx.doi.org/10.3390/jcs6060178.

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This paper presents some examples of ceramic matrix composites (CMCs) reinforced with metal or intermetallic phases fabricated by powder consolidation without a liquid phase (melted metal). Composites with a complex structure, which are an advanced group of CMCs called hybrid composites, were described in contrast to conventional composites with a ceramic matrix. In advanced CMCs, their complex structures make it possible to achieve the synergistic effect of the micro- and nanoparticles of the metallic, intermetallic, and ceramic phases on the composite properties, which is not possible in conventional materials. Various combinations of substrates in the form of powder as more than one metal and ceramics with different powder sizes that are used to form hybrid composites were analyzed. The types of CMC microstructures, together with their geometrical schemas and some examples of real ceramic matrix composites, were described. The schemas of composite microstructures showed the possible location of the ceramic, metallic, or intermetallic phases in composites. A new concept of an advanced ceramic–intermetallic composite fabricated by the consolidation of pre-composite powder mixed with ceramic powder was also presented. This concept is based on the selection of substrates, two metals in the form of powder, which will form a new compound, intermetallic material, during processing. Metal powders were milled with ceramic powders to obtain a pre-composite powder consisting of intermetallic material and ceramics. In the next step, the consolidation of pre-composite powder with ceramic powder allows the creation of composites with complex microstructures. Selected examples of real particle-reinforced conventional and hybrid microstructures based on our own investigations were presented. In addition to microstructures, the properties and possible applications of CMCs were analyzed.

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Wang, Zhong, Hui Chen, Ying Chu, Yan Cheng, Lei Zhu, Xu Yu Jian i Hai Jun Yu. "Thermoelectric Properties P-Type Si-20 at % Ge by Addition of TiN Nanoparticles". Materials Science Forum 610-613 (styczeń 2009): 399–402. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.399.

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SiGe alloy composite material including TiN nanoparticle were prepared. The TiN nanoparticles as the inert scattering center were fabricated by Nitrogen plasma-metal reaction. The sintered samples were characterized by electrical resistivity and seebeck coefficient measurement. Adding nanophase inclusion into the SiGe alloy matrix, the Seebeck coefficient increased, the electrical conductivity decreased and the electrical power factor only slightly reduced.

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Nikitin, Andrey, Alexander Zvekov, Alexander Kalenskii, Marina Ananeva i Denis Nurmukhametov. "Absorption profile of laser impulse of composites based on transparent matrix and metal nanoparticles". Thermal Science 23, Suppl. 2 (2019): 553–60. http://dx.doi.org/10.2298/tsci19s2553n.

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In this work the technique of modeling of optoacoustic signal initiated by laser pulse in composites based on transparent matrix and metal nanoparticles was proposed. It was shown that the time to achieve mechanical equilibrium is significantly lower than the pulse duration, and pressure is proportional to the augmentation of the nanoparticles? temperature. Testing of the modeling technique was carried out on the example of PETN - aluminum nanoparticles composite in two variant with and without taking into account the temperature dependence of the composites? optical properties. Comparison of calculated and experimental dependences of the effective absorption coefficient on the energy density of neodymium laser with pulse duration 14 ns was made. The modeling results are in good agreement with the experimental data only if the temperature dependence of the optical properties is taken into account.

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Al-Jumaili, Ahmed, Avishek Kumar, Kateryna Bazaka i Mohan V. Jacob. "Electrically Insulating Plasma Polymer/ZnO Composite Films". Materials 12, nr 19 (23.09.2019): 3099. http://dx.doi.org/10.3390/ma12193099.

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In this report, the electrical properties of plasma polymer films functionalized with ZnO nanoparticles were investigated with respect to their potential applications in biomaterials and microelectronics fields. The nanocomposite films were produced using a single-step method that combines simultaneous plasma polymerization of renewable geranium essential oil with thermal decomposition of zinc acetylacetonate Zn(acac)2. The input power used for the deposition of composites were 10 W and 50 W, and the resulting composite structures were abbreviated as Zn/Ge 10 W and Zn/Ge 50 W, respectively. The electrical properties of pristine polymers and Zn/polymer composite films were studied in metal–insulator–metal structures. At a quantity of ZnO of around ~1%, it was found that ZnO had a small influence on the capacitance and dielectric constants of thus-fabricated films. The dielectric constant of films with smaller-sized nanoparticles exhibited the highest value, whereas, with the increase in ZnO particle size, the dielectric constant decreases. The conductivity of the composites was calculated to be in the in the range of 10−14–10−15 Ω−1 m−1, significantly greater than that for the pristine polymer, the latter estimated to be in the range of 10−16–10−17 Ω−1 m−1.

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Balhaddad, Abdulrahman A., Isadora M. Garcia, Lamia Mokeem, Rashed Alsahafi, Fabrício Mezzomo Collares i Mary Anne Sampaio de Melo. "Metal Oxide Nanoparticles and Nanotubes: Ultrasmall Nanostructures to Engineer Antibacterial and Improved Dental Adhesives and Composites". Bioengineering 8, nr 10 (19.10.2021): 146. http://dx.doi.org/10.3390/bioengineering8100146.

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Advances in nanotechnology have unlocked exclusive and relevant capabilities that are being applied to develop new dental restorative materials. Metal oxide nanoparticles and nanotubes perform functions relevant to a range of dental purposes beyond the traditional role of filler reinforcement—they can release ions from their inorganic compounds damaging oral pathogens, deliver calcium phosphate compounds, provide contrast during imaging, protect dental tissues during a bacterial acid attack, and improve the mineral content of the bonding interface. These capabilities make metal oxide nanoparticles and nanotubes useful for dental adhesives and composites, as these materials are the most used restorative materials in daily dental practice for tooth restorations. Secondary caries and material fractures have been recognized as the most common routes for the failure of composite restorations and bonding interface in the clinical setting. This review covers the significant capabilities of metal oxide nanoparticles and nanotubes incorporated into dental adhesives and composites, focusing on the novel benefits of antibacterial properties and how they relate to their translational applications in restorative dentistry. We pay close attention to how the development of contemporary antibacterial dental materials requires extensive interdisciplinary collaboration to accomplish particular and complex biological tasks to tackle secondary caries. We complement our discussion of dental adhesives and composites containing metal oxide nanoparticles and nanotubes with considerations needed for clinical application. We anticipate that readers will gain a complete picture of the expansive possibilities of using metal oxide nanoparticles and nanotubes to develop new dental materials and inspire further interdisciplinary development in this area.

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Alzahrani, Fatimah Mohammed, Norah Salem Alsaiari, Khadijah Mohammedsaleh Katubi, Abdelfattah Amari i Mohamed A. Tahoon. "Synthesis, Characterization, and Application of Magnetized Lanthanum (III)-Based Metal-Organic Framework for the Organic Dye Removal from Water". Adsorption Science & Technology 2022 (18.07.2022): 1–14. http://dx.doi.org/10.1155/2022/3513829.

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A hybrid composite based on metal-organic framework (MOF) was chemically fabricated by embedding the magnetic Fe3O4 nanoparticles within amino-functionalized porous La-MOF (MOF/NH2) to produce a highly efficient and reusable composite of MOF/NH2/Fe3O4. Different proper techniques were used for the characterization of surface morphology and chemical arrangement of the prepared MOF/NH2/Fe3O4 composite. The characterization results using various techniques including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer, Emmett, and Teller analysis (BET), and vibrating sample magnetometer (VSM) approved the successful fabrication of MOF with amino arms on its surface besides the well magnetization using magnetic nanoparticles. The MOF/NH2/Fe3O4 composite showed enhanced adsorption capacity (618 mg/g) toward methyl orange (MO) anionic dye which is higher than many commercial reported adsorbents due to the presence of many types of adsorption sites (NH2 groups and lanthanum sites), large surface area of MOF, and the synergetic effect of magnetic nanoparticles. Moreover, the MOF/NH2/Fe3O4 composite showed selective adsorption of MO dye from dye mixtures owing to the electrostatic attraction. Also, the MOF/NH2/Fe3O4 composite retained over 90% of its efficiency for the dye removal even after six successive cycles. So, the present study provided a practical strategy for the design of functional MOF hybrid composites. Furthermore, due to the adaptability of its architectural form, it is a potential adsorbent material for industrial wastewater treatment uses.

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Anh, Nguyen Duy. "STUDY ON SYNTHESIS OF MnFe2O4/GNPs COMPOSITE AND APPLICATION ON HEAVY METAL REMOVAL". Vietnam Journal of Science and Technology 56, nr 1A (4.05.2018): 204. http://dx.doi.org/10.15625/2525-2518/56/1a/12524.

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Nowadays, composite materials between mixed-metal oxides and graphene are widely studied due to their multiple applications on different fields. MnFe2O4 is a magnetic material which has the ability to absorb toxic heavy metal in water. Graphene nanoplatelets (GNPs) with about 10 layers, is one of type of graphene. GNPs was used as matrix for the fine distribution of metal oxide nanoparticles. Surface area for the absorption process can be increased. Composite was synthesized using solvothermal method, in which mixed-metal oxide nanoparticles were directly formed in-situ from precursor salts onto GNPs surface. Synthesized material was analyzed using XRD, SEM and EDX methods to determine its properties. Heavy metal absorption capacity was also studied and showed good results.

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