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The effect of magnetite nanoparticles synthesis conditions on their ability to separate heavy metal ions

. (2011). Historical development of magnetite nanoparticles synthesis, Journal of The Chemical Society Of Pakistan, 33(6), pp. 793-804. Liu, J.F., Zhao, S.Z. & Jiang, G.B. (2008). Coating Fe3O4 Magnetite nanoparticles with humic acid for high effi cient removal of heavy metals in water, Environmental Science & Technology, 42, pp. 6949-6954. Maity, D. & Agrawal, D. (2006), Synthesis of iron oxide nanoparticles under oxidizing environment and their stabilization in aqueous and non-aqueous media, Journal of Magnetism and Magnetic Materials

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Preparation and characterization of cobalt and copper oxide nanocrystals

Abstract

Copper oxide and cobalt oxide (Co3O4, CuO) nanocrystals (NCs) have been successfully prepared using microwave irradiation. The obtained powders of the nanocrystals (NCs) were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric (TGA) analysis and Fourier-transform infrared spectroscopy. The obtained results confirm the presence of both nanooxides which have been produced during chemical precipitation using microwave irradiation. TEM micrographs have shown that the obtained nanocrystals are characterized by high dispersion and narrow size distribution. The results of X-ray diffraction confirmed those obtained from the transmission electron microscope. Optical absorption analysis indicated the direct band gap for both kinds of the nanocrystals.

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ZnFe2O4 Containing Nanoparticles: Synthesis and Magnetic Properties

Abstract

Solid solutions of Co1− xZnxFe2O4 and Ni1− xZnxFe2O4 (0 < x < 1) nanoparticles were synthesized by sol-gel self-propagating combustion method. The obtained single cubic phase product has a specific surface area 25 m2∙g−1 to 33 m2∙g−1 and crystallite size 25 nm to 40 nm. Lattice parameters change linearly from 8.371 A (CoFe2O4) and 8.337 A (NiFe2O4) to 8.431 A (ZnFe2O4). The saturation magnetization (Ms) changes non-linearly from 60.8 emu∙g−1 (CoFe2O4), respectively, from 35.6 emu∙g−1 (NiFe2O4) to 3.3 emu∙g−1 (ZnFe2O4) reaching maximal value 76.1 emu∙g−1 for Co0.8Zn0.2Fe2O4 and 64.9 emu∙g−1 – for Ni0.6Zn0.4Fe2O4.

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Mixed structure Zn(S,O) nanoparticles: synthesis and characterization

Abstract

In the present work, mixed structure Zn(S,O) nanoparticles have been synthesized using solution based chemical coprecipitation technique. Two different zinc sources (Zn(CH3COO)2·2H2O and ZnSO4·7H2O) and one sulfur source (CSNH2NH2) have been used as primary chemical precursors for the synthesis of the nanoparticles in the presence and absence of a capping agent (EDTA). The structural, morphological, compositional and optical properties of the nanoparticles have been analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transmission infra-red (FT-IR) and UV-Visible (UV-Vis) spectroscopy. XRD revealed the formation of mixed phases of c-ZnS, h-ZnS and h-ZnO in the synthesized nanoparticles. The surface morphology was analyzed from SEM micrographs which showed noticeable changes due to the effect of EDTA. EDX analysis confirmed the presence of zinc, sulfur and oxygen in Zn(S,O) nanoparticles. FT-IR spectra identified the presence of characteristic absorption peaks of ZnS and ZnO along with other functional group elements. The optical band gap values were found to vary from 4.16 eV to 4.40 eV for Zn(S,O) nanoparticles which are higher in comparison to the band gap values of bulk ZnS and ZnO. These higher band gap values may be attributed to the mixed structure of Zn(S,O) nanoparticles.

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Green synthesis of silver nanoparticles using tannins

. Phys. Chem. B, 107 (2003), 11267. http://dx.doi.org/10.1021/jp030116s [14] Hubenthal F., Noble Metal Nanoparticles: Synthesis and Optical Properties, in: Andrews D.L., Scholes G.D., Wiederrecht G.P. (Eds.), Comprehensive Nanoscience and Technology. Volume 1: Nanomaterials, Elsevier B.V., New York, 2011, p. 375. http://dx.doi.org/10.1016/B978-0-12-374396-1.00034-9 [15] Jin E.S., Ghodake G.S., Deshpande N.G., Lee Y.P., Colloid. Surface. B, 75 (2010), 584. http://dx.doi.org/10.1016/j.colsurfb.2009

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Nanoparticle shapes: Quantification by elongation, convexity and circularity measures

anisometric magnetite nanoparticles”, Acta Materialia , vol. 125, pp. 416–424, 2017. [6] A. H. Lu, E. E. Salabas and F. Schüth, “Magnetic nanoparticles: synthesis, protection, functionalization, and application”, Angewandte Chemie International Edition , vol. 46, pp. 1222–1244, 2007. [7] A. Nagata, H. Sato, Y. Matsui, T. Kaneko and Y. Fujiwara, “Magnetic properties of carbon nanotubes filled with ferromagnetic metals”, Vacuum , vol. 87, pp. 182–186, 2013. [8] L. Kopanja, D. Žunić, B. Lončar, S. Gyergyek and M. Tadić, “Quantifying shapes of nanoparticles

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Biochemical Changes in Nostoc linckia Associated with Selenium Nanoparticles Biosynthesis

Abstract

The cyanobacterium Nostoc linckia was used to study the biotechnology of selenium nanoparticles synthesis for the first time. The experimental conditions of the nanoparticle production by the studied cyanobacteria in aqueous cobalt selenite solutions were examined. Neutron activation analysis allowed characterization of the dynamics of accumulation of the total selenium quantity by Nostoc linckia. Scanning Electron Microscope images demonstrated extracellular formation of amorphous nanoparticles. Released selenium nanoparticles ranged in size from 10 to 80 nm. The changes of essential parameters of biomass (proteins, lipids, carbohydrates, and phycobilin) content during the nanoparticle formation were assessed. During the first 24 h of nanoparticle synthesis, a slight decline of proteins, lipids and carbohydrates content in the biomass was observed. The most extensive was the process of phycobilin degradation. Furthermore, all biochemical component content as well as an antioxidant activity of the biomass extracts significantly decreased. The obtained substance of Nostoc biomass with selenium nanoparticles may be used for medical, pharmaceutical and technological purposes.

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Deposition of gold nanoparticles from colloid on TiO2 surface

R eferences [1] S. Horikoshi and N. Serpone, Microwaves Nanoparticle Synthesis: Fundamentals and Applications , first ed., Wiley-VCH Verlag GmbH & Co.KGaA, 2013. [2] Y. Zhang, W. Chu, A. D. Foroushani, H. Wang, D. Li, J. Liu, C. J. Barrow, X. Wang, W. And and Yang, “New Gold Nanostructures for Sensor Applications: A Review”, Materials 7 , 2014, pp. 5169-5201. [3] M. C. Daniel and D. Astruc, “Gold Nanoparticles: Assembly, Supramolecular Chemistry, Quantum-Size-Related Properties, and Applications toward Biology, Catalysis and Nanotechnology

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Preparation of iron oxide nanocatalysts and application in the liquid phase oxidation of benzene

References 1. Wu, S., Sun, A., Zhai, F., Wang, J., Xu, W., Zhang, Q. & Volinsky, A.A. (2011). Fe3O4 magnetic nanoparticles synthesis from tailings by ultrasonic chemical co-precipitation. Mat. Lett. 65, 1882-1884. DOI: 10.1016/j.matlet.2011.03.065. 2. Rafi ee, H.R., Feyzi, M., Jafari, F. & Safari, B. (2013). Preparation and characterization of promoted Fe-V/SiO2 nanocatalysts for oxidation of alcohols. J. Chem. 2013, 1-10. DOI: 10.1155/2013/412308. 3. Skandan, G. & Singhal, A. (2006). Perspectives on the science

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Assessment Of Biologically Synthesized Ag Nanoparticles Toxicity Against E. coli, Staphylococcus aureus, Parachlorella kessleri And Sinapis alba

. Safe, 78, 2012, 80-85. PAL, S., TAK, Y.K., SONG, J.M.: Does the antibacterial activity of silver nanoparticles depend on the shape of the nanoparticles? A study of the gram-negative bacterium Escherichia coli . App. Environ. Microbiol., 27, 6, 2007, 1712-1720. PANACEK, A., KVITEK, L., PRUCEK, R., KOLAR, M., VECEROVA, R,, PIZUROVA, N,, SHARMA, V.K., NEVECNA, T., ZBORIL, R.: Silver colloid nanoparticles: Synthesis, characterization, and their antibacterial activity. J. Phys. Chem. B, 110, 2006, 16248-16253. RAI, M., YADAV, A., GADE, A.: Silver

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