Nanoparticles status

C. R. Henry, in Catalysis and Electrocatalysis at Nanoparticle Surfaces, eds. A. Wieck-owski, E. R. Savinova, C. G. Vayenas, Marcel Dekker Inc., New York NY, 2003, p. 239. H. J. Freund, N. Ernst, T. Risse, H. Hamann and G. Rupprechter, Physica Status Solidi A Applied Research, 2001, 187, 257. 

Askay, I. Nanostructured ceramics through self-assembly, in Seigel, R. W., Hu, E. and Roco, M. C. (eds) R D Status and Trends in Nanoparticles, Nanostructured Materials and Nanodevices in the United States, International Technology Research Institute, Baltimore, MD, USA, 1998. 

D. Hill, T. Jawhari, J.G. Cespedes, J.A. Garcia and E. Bertran, In-situ monitoring of laser annealing by micro-Raman spectroscopy for hydrogenated silicon nanoparticles produced in radio frequency glow discharge, Phys. Status SolidiA, 203, 1296-1300 (2006). 

Handy, R.D., Owen, R. and Valsami-Jones, E. (2008) The ecotoxicology of nanoparticles and nanomaterials current status, knowledge gaps, challenges, and future needs. Ecotoxicology, 17, 315-325. 

WTEC Panel Report on Nanostructure Sdence and Technology R D Status and Trends in Nanoparticles, Nanostructured Materials and Nanodevices, www.nano.gov (accessed 26/08/07). 

This journal publishes new and original experimental and theoretical basic research directed toward researchers in materials, interfaces, and biophysical chemistry. Coverage includes new findings and full-length studies of physical chemistry of materials from nanoparticles to macromolecules physical chemistry of surfaces and interfaces statistical mechanics and thermodynamics of condensed matter and biophysical chemistry. Invited papers review the status of a particular topic, clarify controversies, or explore future directions. Proceedings of selected symposia and special thematic issues appear throughout the year. Rapid publications of urgent and new results appear in the Letters section. 

It is particularly noteworthy that the EPA states that names assigned to certain nano-substances and even their TSCA Inventory status may change as new nomenclature conventions are developed. The EPA recently made regulatory decisions for certain nanoparticles... 

TSCA does not authorize the EPA to distinguish between chemical substances based on the their particle size, and the EPA states clearly in the Inventory Status of Nanoscale Substances that particle size alone is not a basis for characterizing a substance as a new chemical if either the bulk form or nanoscale form of the chemical is on the Inventory. Therefore, the bulk form of titanium dioxide is on the Inventory and so nanoparticles of titanium dioxide are considered to be on the Inventory. When a nanoscale form of a substance is put on the Inventory, the bulk form is also considered to be on the Inventory. 

Without special conditions, the size distribution of as-prepared particles is broad. However, by varying the temperature the use of only partially soluble precursor complexes supersaturation of metal atoms in solution can be avoided, such that the solid material will serve as a type of reservoir. Long-chain polyalcohols such as 1,2-hexanediol [35] can also act as protectors, similar to other materials such as PVP, to help control particle size distribution [36-38]. Previously, PVP was applied to the generation of numerous monodisperse metal nanoparticles of Pd [39,40], Pt [40], and Au [41]. A series of alloy-like nanopartides has also been prepared using the polyol method [35, 42-54]. Monodisperse particles of Pd and Ag could be generated if they were to be deposited on alumina in status nascendi, a technique that may be helpful for the generation of heterogeneous catalysts. 

Perhaps one of the most demanding challenges in current preparational research is the directed coupling of semiconductor nanoparticles. If the QDs were called artificial atoms, this endeavor would yield artificial molecules, and the challenge would be to create such QD molecules in a desired maimer to form, for example, dimers ( two-atomic QD molecules ) of various compositions, AB4 molecules, and so on. As the field is about to emerge from its infant status, the very first attempts in this direction are reported in the following sections. 

Oxonica website. You can find out about the status of the nanoparticle fuel efficiency trials. 

Bonsak, J., Mayandi, J., Th0gersen, A., Marstein, E.S., Mahalingam, U., 2011. Chemical synthesis of silver nanoparticles for solar cell applications. Phys. Status Solidi C 8, 924-927. 

Yazyev OV, Pasquarello A. Carbon diffusion in CVD growth of carbon nanotubes on metal nanoparticles. Phys Status SoUdi B 2008 284-7. 

Peng KQ, Zhu J (2004) Morphological selection of electroless metal deposits on silicon in aqueous fluoride solution. Electrochim Acta 49 2563-2568 Polisski S, Goller B, Lapkin A et al (2008) Synthesis and catalytic activity of hybrid metal/silicon nanocomposites. Phys Status Solidi RRL 2 132-134 Polisski S, Goller B, Heck SC et al (2011) Formation of metal nanoparticles in silicon nanopores plasmon resonance studies. Appl Phys Lett 98 011912 Renaux C, Scheuren V, Flandre D (2000) New experiments on the electrodeposition of iron in porous silicon. Microelectron Reliab 40 877-879 Ronkel F, Schultze JW, Arens-Fischer R (1996) Electrical contact to porous silicon by electrodeposition of iron. Thin Sohd Films 276 40—43... 

The increase of oral bioavailability can he explained by the adhesiveness of the drug nanopaiticles to the mucosa, the increased saturation solubility leading to an increased concentration gradient between gastrointestinal tract lumen and blood, and the increa.sed dissolution velocity of the drug. The reduction of erratic absorption can be explained by the fact that the adhesion proces.s of the drug-nanoparticles to the muco.sal surface seems to be highly reproducible and little affected by the nutritional status of the patient. 

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