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Temperature measurement using a Chx/porous silicon/Si structure encapsulated in a CO2 rich environment

Temperature measurement using a Chx/porous silicon/Si structure encapsulated in a CO2 rich environment

This work reports on the possible use of microporous silicon as a temperature sensor. This work is based on previous published works [7, 8, and 9]. The device is based on hydrocarbon group (CHx) / porous silicon (PS) /Si structure. The porous sample was coated with hydrocarbons groups deposited by the plasma of methane /argon mixture. Current-voltage characteristics have been investigated as a function of temperature in the range 20°C-70°C. The results show that for a constant voltage in the range 0.7-1V, the current increases linearly with the environment temperature reaches a maximum at 70°C and then stabilizes. This result suggests that the developed structure can be used for sensing temperatures not exceeding 70°C.

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Green synthesis and spectral analysis of surface encapsulated copper (II) oxide nanostructures

Abstract

Nanostructures of copper (II) oxide were synthesized through chemical reduction of copper (II) sulfate pentahydrate using phytochemicals present in leaf extracts of Leucas aspera. The crystalline phases and size were assessed by X-ray diffraction data analysis. From the Bragg reflection peaks, existence of monoclinic end-centered phase of copper (II) oxide along with presence of cubic primitive phase of copper (I) oxide and traces of cubic face centered lattices of zero valent copper was revealed. The three Raman active modes corresponding to CuO phase were identified in the sample with permissible merging of characteristic bands due to nanostructuring and organic capping. The surface topography measurement using field emission scanning electron microscope evidenced the occurrence of cylindrical rod shaped morphological structures along with a number of unshaped aggregates in the sample. The effective crystallite size and lattice strain were estimated from Williamson-Hall analysis of Bragg reflection data. Tauc plot analysis of UV-Vis-NIR absorption data in direct transition mode provided an estimation of band gap, viz. 1.83 eV and 2.06 eV respectively, for copper (II) oxide and copper (I) oxide. Thermal degradation study using thermogravimetric curve analysis could reveal the amount of moisture content, volatile components as well as the polymer capping over nanorods present in the sample. It could be seen that upon heating, inorganic core crystals undergo oxidation process and at temperature above 464 °C, the sample was found to be composed solely of inorganic crystallite phase of copper (II) oxide.

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NANOTECHNOLOGIES IN DEVELOPMENT OF STRUCTURAL MATERIALS AND BIOMATERIALS

-15. http://www.plasmachem.com/contentenglish/nanopowders_technology.html Chen H., Huang R. B., Tao Z. C., Zheng L.-S., Zhou G.-W., Zhang Z.: Single titanium crystals encapsulated in carbon nanocages obtained by laser vaporization of sponge titanium in benzene vapor. Appl. Phys. Lett. 77 (2000) 91-93. Zhu S., Su C.-H., Cochrane J. C., Lehoczky S., Muntele I., Ila D.: Growth of carbon nanostructure materials using laser vaporization. Diamond Related Mater. 10 (2001) 1190-1194. Roca i Cabarrocas

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Structure and Properties of Polyacrylonitrile/Polystyrene and Carbon Nanoparticle-Based Nanocomposite Foams

, M.L.P., Rodrigues, D.F.: Improved removal of lead (II) from water using a polymer-based graphene oxide nanocomposite. Journal of Materials Chemistry A 1 (2013) 3789-3796. 38. Pyrzyńska, K., Bystrzejewski, M.: Comparative study of heavy metal ions sorption onto activated carbon, carbon nanotubes, and carbon-encapsulated magnetic nanoparticles. Colloids and Surfaces A: Physicochemical and Engineering Aspects 362 (2010) 102-109. 39. Zhao, X., Jia, Q., Song, N., Zhou, W., Li, Y.: Adsorption of Pb (II) from an aqueous solution by titanium dioxide

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Structural and electrical properties of new core-shell silver poly(m-toluidine-co-2-bromoaniline) nanocomposites

Abstract

In this article, we report the synthesis and characterization of silver dispersed poly(m-toluidine-co-2-bromoaniline) copolymer synthesized by chemical oxidative polymerization method. The synthesized copolymer composites were subjected to different analytical characterization methods, such as FT-IR, UV, XRD, SEM, photoluminescence and electrical conductivity studies. All the polymer samples are found to be soluble in common organic solvents. UV absorption spectra show a red shift when silver nanoparticles are dispersed in the copolymer. The characteristic peaks observed in FT-IR spectra confirm the formation of the copolymer. XRD pattern reveals the crystalline nature of the copolymer composites and sharp peaks in the spectra confirm the presence of silver particles. The silver nanoparticles change the surface morphology in the form of perfect encapsulation. The electrical conductivity of the polymer composites is found to vary from 10−4 S/cm to 10−6 S/cm. PL study reveals the charge transfer between the copolymer and the silver particles.

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Structural, electronic and magnetic properties of Fe, Co, Ni monatomic nanochains encapsulated in armchair LiF nanotubes

Abstract

Structural, electronic and magnetic properties of transition metal TM (TM = Fe, Co and Ni) atomic chains wrapped in single walled LiF armchair nanotubes have been investigated by the first-principles calculations in the framework of the density functional theory. The generalized gradient approximation (GGA) with Hubbard repulsion potential and without Hubbard repulsion was employed to describe the exchange-correlation potential. It is found that all these TM chains @LiFNTs systems have negative formation energy so they are stable and exothermic. Total density of states and partial densities of states analyses show that the spin polarization and the magnetic moment of TM chains @LiFNTs(n,n) systems come mostly from the TM atom chains. All these nanocomposites are ferromagnetic (FM) and spin splitting between spin up and down is observed. The high magnetic moment and spin polarization of the TM chains @LiFNT(n,n) systems show that they can be used as magnetic nanostructures possessing potential current and future applications in permanent magnetism, magnetic recording, and spintronics.

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Polystyrene/magnetite nanocomposite synthesis and characterization: investigation of magnetic and electrical properties for using as microelectromechanical systems (MEMS)

, 21 ]. Various methods for magnetic nanoparticles preparation, such as sol-gel process [ 22 ], hydrothermal process [ 23 ] and co-precipitation [ 24 , 25 ], have been reported in the literature. For magnetite/polymer nanocomposite preparation, magnetite nanoparticles are coated or encapsulated by natural or synthetic polymer. Various studies have been performed to prepare magnetic polymeric particles [ 26 ]. In one of those methods, magnetic inorganic particles and polymer particles are synthesized separately and then mixed together for enabling either physical

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Synthesis and characterization of Ag@polycarbazole nanoparticles using different oxidants and their dispersion behavior

analytical applications: in detection of metal ions, CO 2 and N containing bases, such as ammonia, amine, and nucleotides. They can also be transformed into a film to investigate the electro/photo conductivity and electric and optical chromic behavior [18] . Fig. 4. Zeta potential measuring the dispersion behavior of (a) Ag NPs, (b) Ag +1 based Ag nanocomposite, and (c) Fe +3 based Ag nanocomposite, respectively. 5. Conclusion The Ag NPs encapsulated by PCz were synthesized in two steps. The first step was a synthesis of Ag NPs by polyol reduction

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Synthesis and crystal structure of chlorate-enclathrated in aluminogermanate sodalite Na8[AlGeO4]6(ClO3)2

Abstract

Encapsulation of chlorate in sodalite with aluminogermanate host framework has been obtained by one pot hydrothermal synthesis at 393 K. The crystal structure of Na8[AlGeO4]6(ClO3)2; sodalite was refined from X-ray powder data in the space group P$\bar 4$3n: a = 9.169 Å, where Al-O-Ge angle is 137.6°. The 27Al MAS NMR study confirmed alternate Ge and Al ordering of the sodalite framework, while 23Na gave insight into the structure and dynamics of the cage fillings. Infrared spectrum confirmed the encapsulation of chlorate as well as the framework formation of aluminogermanate sodalite. SEM study showed the retention of cubical morphology of the aluminogermanate sodalite. Thermogravimetric analysis provided information on the extent of chlorate entrapment, stability within the sodalite cages and decomposition properties.

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TiO2/PANI nanocomposite loaded in PVA for anticorrosive applications

40 % [ 32 ]. We have further compared the correlation coefficient from our results with PANI-PVA [ 33 ], PANI-SnO 2 nanohybrid material [ 32 ] and nano-TiO 2 + PANI [ 36 ]. The values of the correlation coefficients have been given in Table 1 . The correlation coefficient shows that the synthesized PANI was deposited on the surface of nano-TiO 2 material and formsp encapsulated structure [ 36 ]. This encapsulated nanocomposite material (nano-TiO 2 + PANI) when loaded to PVA stabilizer made a conductive nanocomposite which showed a good correlation coefficient, i

Open access