Mohammad E. Khosroshahi

Bio: Mohammad E. Khosroshahi is an academic researcher from University of Toronto. The author has contributed to research in topics: Laser & Nanoshell. The author has an hindex of 16, co-authored 96 publications receiving 914 citations. Previous affiliations of Mohammad E. Khosroshahi include Amirkabir University of Technology & University of Hull.

Preparation and characterization of silica-coated iron-oxide bionanoparticles under N2 gas

Abstract: This paper describes coating of magnetite nanoparticles with silica shells. Controlled co-precipitation technique under N2 gas was used to prevent undesirable critical oxidation of Fe2+. The synthesized Fe3O4 (3 1 1) NPs were first coated with trisodium citrate (T S C) to achieve solution stability and then covered by SiO2 layer using stober method. For uncoated Fe3O4 NPs, the results showed an octahedral geometry with saturation magnetization range of (82–96) emu/g and coercivity of about (80–120) Oe for particles between (35–96)nm, respectively. The best value of specific surface area (41 m2/g) was obtained at 0.9 M NaOH at 750 rpm. However, it increased to about 81 m2/g for Fe3O4/SiO2 combination with 50 nm as particle size, indicating the presence of about 15 nm SiO2 layer. Finally, the stable magnetic fluid contained well-dispersed magnetite–silica nanoshells which showed fast magnetic response.

Unit Response Approach for Priority Determination of Flood Source Areas

Abstract: Flood damages are usually concentrated along certain reaches of the main watercourse. However, a successful flood-control project must look beyond the damaged reaches by studying the contribution of headwater subwatersheds to the flood magnitude at downstream locations. Flood-control measures may then be initially planned in identified flood tributary areas of the watershed that strongly affect the flood peak at downstream river reaches. A simple iterative simulation technique is introduced, whereby the contribution of each subwatershed unit or group of subwatershed units to the flood peak response can be disaggregated. A flood index may then be assigned to each contributing unit to determine the change in response of outlet flood discharge caused by removal of that unit. The technique is similar to the unit response approach in groundwater studies. The proposed technique is applied to a watershed; and the effect of such different factors as design return period, storm duration, and size of the contributing subunits are examined. The interpretation of results is based particularly on the flood index corresponding to the contribution at the outlet per unit area of subwatersheds. For the watershed under study, the flood index analysis showed that while the differences in the contribution of subwatershed units may be salient for up to 100-year return periods, the contribution per unit area is expected to converge for rare floods. Moreover, subwatershed units that have larger area or that are nearer to the outlet may not necessarily generate higher flood contributions.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Mechanisms of pulsed laser ablation of biological tissues.

Abstract: Author(s): Vogel, Alfred; Venugopalan, Vasan | Abstract: The mechanisms of pulsed laser ablation of biological tissues were studied. The transiently empty space created between the fiber tip and the tissue surface improved the optical transmission to the target and thus increased the ablation efficiency. It was found that the structure and morphology also affect the energy transport among tissue constituents.

A review of indocyanine green fluorescent imaging in surgery

Abstract: The purpose of this paper is to give an overview of the recent surgical intraoperational applications of indocyanine green fluorescence imaging methods, the basics of the technology, and instrumentation used. Well over 200 papers describing this technique in clinical setting are reviewed. In addition to the surgical applications, other recent medical applications of ICG are briefly examined.