Nanoparticles powder

Hydrothermal reactions typically produce nanometer-sized particles that can be quenched to form a nanoparticle powder or cross-linked to produce nanocrystalline stmctures (Feng and Xu, 2001). Hydrothermal conditions allow for reduction in solubilities of ionic materials and thus more rapid nucleation and increased ion mobility, resulting in faster growth. Via judicious choice of the hydrothermal conditions, a measure of control can be exerted over the size and morphology of the materials. As mentioned earlier, the viscosity and ionic strength of solvents is a function of the temperature and pressure at which the reaction is carried out. Other experimental parameters, such as the precursor material and the pH, have... 

The working electrode consisted of a mirror pohshed platinum disc, or a gold disc or glassy carbon (GC) disk (diameter 8 nun) glued to a glass tube as the holder. For nanoparticle powders the catalyst suspension was deposited on the GC disk and the solvent was evaporated under a pure nitrogen stream. 

S. H. Chen and K. Kimura, Synthesis and characterization of carboxylate-modified gold nanoparticle powders dispersible in water, Langmuir, 15 (1999) 1075-1082. 

Liu, S., Tao, D., and Zhang, L. Cellulose scaffold A green template for the controlling synthesis of magnetic inorganic nanoparticles. Powder Technology, 217(0), 502-509 (2012). 

The above consideration of nanoparticles has been carried out in a supposition that they have more or less the same size. To be more precise, we assumed that the width of the nanoparticles sizes distribution function is smaller then its mean value. The mean value R is usually extracted from, e.g., X-Ray diffraction measurements [91] and it is supposed, that the size of all the particles corresponds to R. In this part we will show, that the neglection of sizes distribution can lead to incorrect results, when measurements are performed on the samples with essential scattering of sizes. Besides that, actually the size distribution defines the spectral lines inhomogeneous broadening. Moreover, it essentially influences the observed anomalies of many physical properties (like specific heat and dielectric or magnetic permittivity) of nanomaterials. Note that in real nanomaterials, like nanoparticles powders and/or nanogranular ceramics there is unavoidable size distribution which in general case should be taken into account. However, we will show below, that in perfect samples, where the width of size distribution is small, it is possible to suppose safely that all particles have the same size. In this part we primarily follow the approaches from the paper [92]. 

Forny, L., Saleh, K., Pezron, I., Komunjer, L., and Guigon, P. 2009. Influence of mixing characteristics for water encapsulation by self-assembling hydrophobic silica nanoparticles. Powder Technol. 189 263-269. 

Peng ZB, Doroodchi E, Evans G (2010) DEM simulation of aggregation of suspended nanoparticles. Powder Technol 204 91-102... 

Reaerosolization of bulk nanomaterials Handling of nanoparticle powders may present a particle inhalation hazard (although this needs to be verified) but not necessarily in the nanometer size range. When nanoparticles are collected as powders, adhesion forces between adjacent particles are significantly large such that these materials may prove... 

H41C, H53C ZnO/Hec/H53C, H80C ZnO/Hec/H80C, SIOOC ZnO nanoparticle powder dried at 100 °C, Ref. reference ZnO in 0.1 wt/ Fig. 8 XRD patterns of Sn02/hectorite nanocomposites containing... 

Shen, M., Du, Y. K., Hua, N. P., and Yang, P. (2006) Microwave irradiation synthesis and self-assembly of alkylamine-stabilized gold nanoparticles. Powder Technol, 162(1), 64-72. 

E. Tang, G.X. Cheng, X.L. Ma, Preparation of nano-ZnO/PMMA composite particles via grafting of the copolymer onto the surface of zinc oxide nanoparticles. Powder Technology 161(3) (2006) 209-214. 

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