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Microscopy Micrographs (microscopy + micrograph)
Kinds of Microscopy Micrographs Selected AbstractsExamples for the integration of self-organized nanowires for functional devices by a fracture approachPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 10 2010Dawit Gedamu Abstract Simple and versatile methods to form nanowires on microchips are of interest for fundamental research and hold the potentials for an industrial fabrication. In this review article, one of these methods based on thin film fracture will be described introducing the experimental parameters and the potential for research. The advantages of the utilization of thin film cracks as a template for the nanowire formation are numerous: nanowire generation ready with contacts, a wide ranging freedom in the choice of materials, influence on the internal structure of the nanowire or the precise positioning on a microchip. A detailed discussion about the fabrication steps and some preliminary experiments revealing the possibilities of the fracture approach will be given for obtained metallic, semiconducting and anodized nanowires. In contrast to their macroscopic counterparts, the conductivity through the nanowires is entirely different. The influence of the surrounding gas atmospheres and the application of electrical fields demonstrate the applicability of these nanowires fabricated by using such a fracture approach. Perspective scanning electron microscopy micrograph of Au nanowires fabricated by thin film fracture approach between Au contact lines. The wires form a zigzag pattern on the thermally oxidized layer substrate on a silicon chip. [source] Oxidized multiwalled carbon nanotubes as effective reinforcement and thermal stability agents of poly(lactic acid) ligamentsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010K. Chrissafis Abstract In this study, nanocomposites of poly(lactic acid) (PLA) containing 0.5, 1, and 2.5 wt % oxidized multiwalled carbon nanotubes (MWCNT,COOHs) were prepared by the solved evaporation method. From transmission electron microscopy and scanning electron microscopy micrographs, we observed that the MWCNT,COOHs were well dispersed in the PLA matrix and, additionally, there was increased adhesion between PLA and the nanotubes. As a result, all of the studied nanocomposites exhibited higher mechanical properties than neat PLA; this indicated that the MWCNT,COOHs acted as efficient reinforcing agents, whereas in the nonoxidized multiwalled carbon nanotubes, the mechanical properties were reduced. Nanotubes can act as nucleating agents and, thereby, affect the thermal properties of PLA and, especially, the crystallization rate, which is faster than that of neat PLA. From the thermogravimetric data, we observed that the PLA/MWCNT,COOH nanocomposites presented relatively better thermostability than PLA; this was also verified from the calculation of activation energy. On the contrary, the addition of MWCNT,COOH had a negative effect on the enzymatic hydrolysis rate of PLA. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Interfacial formation of porous membranes with poly(ethylene glycol) in a microfluidic environmentJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008Dongshin Kim Abstract In a microfluidic environment, the liquid,liquid interface, formed by laminar flows of immiscible solutions, can be used to generate thin membranes via interfacial polymerization. Because these thin nylon membranes have a very small pore size or lack porosity entirely, their utilization in some biological applications is greatly limited. We introduce an in situ fabrication method using the interfacial reaction of a two-phase system to generate a porous nylon membrane. The membranes were characterized with scanning electron microscopy and fluorescent beads. Scanning electron microscopy micrographs verified the asymmetrical structure of the porous membrane, and the membrane pore sizes ranged from 0.1 to 1 ,m. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008. [source] Comparative Study of Quality Changes Occurring on Dehydration and Rehydration of Cooked Chickpeas (Cicer Arietinum L.) Subjected to Combined Microwave,Convective and Convective Hot Air DehydrationJOURNAL OF FOOD SCIENCE, Issue 6 2006A.A. Gowen ABSTRACT:, Convective hot air dehydration (100 °C) of cooked chickpeas was compared with the combination of microwave,convective hot air dehydration, in terms of microstructure, density, color, texture, dehydration, and rehydration. In the combined drying experiments, 2 levels of microwave power (100 W and 200 W) were investigated, combined continuously with convective air drying at 100 °C. Compared with convective hot air drying, combination drying led to a considerable reduction in dehydration time. Combination drying also improved the porosity of the finished dehydrated product, leading to faster rehydration kinetics. Cryogenic scanning electron microscopy micrographs showed that chickpeas subjected to combined drying experienced less shrinkage than those dried by convective hot air. Combination drying at the higher (200 W) level produced a darker (P < 0.05) rehydrated product with significantly lower relative rehydrated moisture content (P < 0.05) when compared with the lower (100 W) level of combination drying. [source] Sodium Bismuth Titanate-Based Lead-Free Piezoceramics Prepared by Aqueous GelcastingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2008Dongxiang Zhou Aqueous gelcasting for 0.94Bi0.5Na0.5TiO3,0.06BaTiO3 (BNBT6) lead-free piezoceramics was investigated in this paper. A stable BNBT6 suspension with 50 vol% of solid loading and <1Pa·s of viscosity was successfully prepared when 0.5 wt% of PMAA-NH4 was added with the pH value controlled in the range 8,10. Dehydration and desiccation of the gelled parts could be controlled easily through dipping pretreatment with a 5 wt% ammonium persulfate solution for 24 h or with a 10 wt% ammonium persulfate solution for 12 h. Scanning electron microscopy micrographs show that the BNBT6 ceramic prepared by the gelcasting route exhibits a homogeneous microstructure and a high density. Optimal piezoelectric and dielectric properties were obtained: d33=132pC/N, , tg ,=0.019, and kp=0.25. [source] Influence of melt-blending conditions on structural, rheological, and interfacial properties of polyamide-12 layered silicate nanocompositesPOLYMER ENGINEERING & SCIENCE, Issue 8 2006Pascal Médéric The influence of the melt-blending conditions on the structural, rheological, and interfacial properties of modified montmorillonite/Polyamide-12 nanocomposites has been studied performing transmission electron microscopy observation combined with X-Ray diffraction and rheological experiments. In the dilute regime, for short mixing times, the apparent aspect ratio of primary clay entities, determined from intrinsic viscosity measurements, is shown to increase with rotational speed. At high blade rotational speeds, the viscometric results suggest an almost achieved exfoliation, as confirmed by transmission electron microscopy micrographs. For longer mixing times, a significant drop of viscous dissipation is observed, which is very marked at high blade rotational speeds and attributed to a modification of the particle/matrix interface. In the concentrated regime, the rheological behavior of nanocomposites is attributed to the formation of a network of mesoscopic domains, composed of correlated clay entities. Upon increasing strain during mixing, the clay aggregates within these domains break into intercalated stacks and finally exfoliated layers, as shown by transmission electron microscopy micrographs and wide-angle X-ray diffraction patterns. The melt state elastic and viscous properties of the nanocomposites are mainly governed by the networked domains, and not by the nature and properties of the structure within the domains. POLYM. ENG. SCI. 46:986,994, 2006. © 2006 Society of Plastics Engineers. [source] | ||||||||||