Nano-scale 180° structure

The nano-scale structures in polymer layered-silicate nano-composites can be thoroughly characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD is used to identify intercalated structures. XRD allows quantification of changes in layer spacing and the most commonly used to probe the nano-composite structure and... 

Because the composition and nano-scale structure of a catalyst depend on the temperature and the gas environment, it is important to measure catalyst activity under conditions experienced in the industrial converters. For the sulphuric acid catalysts, the activity for conversion of S02 to S03 was measured in the set-up shown in Fig. 9. 

The integrated DLS device provides an example of a measurement tool tailored to nano-scale structure determination in fluids, e.g., polymers induced to form specific assemblies in selective solvents. There is, however, a critical need to understand the behavior of polymers and other interfacial modifiers at the interface of immiscible fluids, such as surfactants in oil-water mixtures. Typical measurement methods used to determine the interfacial tension in such mixtures tend to be time-consuming and had been described as a major barrier to systematic surveys of variable space in libraries of interfacial modifiers. Critical information relating to the behavior of such mixtures, for example, in the effective removal of soil from clothing, would be available simply by measuring interfacial tension (ILT ) for immiscible solutions with different droplet sizes, a variable not accessible by drop-volume or pendant drop techniques [107]. 

In this article I will elaborate on the knowledge, which was obtained by Professor Leroy Eyring and his colleagues in more than 50 years of research on the lanthanide higher oxides and their ideas for the applications of these oxides. Also the unique non-stoichiometric characteristics of the lanthanide higher oxides are emphasized and the intrinsic relationship between the macroscopic properties and nano-scale structures is demonstrated. 

Radhakrishnan and co-workers [6] also studied the freezing of CCI4 in activated carbon fibers (ACF) of uniform nano-scale structures, using Monte Carlo simulation and differential scanning calorimetry (DSC), klicro-porous activated carbon fibers serve as highly attractive adsorbents for simple non-polar molecules. The DSC experiments verified the predictions about the increase in T/. and the molecular results were consistent with equation (1) for pore widths in the mesoporous range they also explained the deviation from the linear behavior in the case of micropores. 

P. H0YRUP, K. Jorgensen, and O.G. Mouritsen. Nano-scale structure in membranes in relation to enzyme action - computer simulation vs. experiment. Comp. Phys. Commun., 2002, 147, 313— 320. 

A rich variety of nano-scale structures and inhomogeneities is very t3rpical of polymers. Fully uniform states are the exception rather than the rule. Now we shall explore yet another peculiarity of polymer structure, by looking at the so-called ionomers. 

Chitosan is a biopolymer that has received much attention and has been extensively studied for micro- and nanoparticles preparation. It is possible, for a given molecular size chitosan, to reduce the particle size to nano level by "bottom-up" approach as a result of a self-assembling or cross-linking processes in which the molecules arrange themselves in to ordered nano scale structure... 

A common approach to the production of nano-scale structures relies on templates that assemble into desired patterns and then can be replicated by a harder, more durable material. Surfactant molecules spontaneously assemble into a variety of useful structures and are commonly used as the template for materials with feature dimensions of a few nanometers, such as zeolites (Kresge et al., 1992). Larger templates are needed for materials with larger dimensions, and polymer beads have recently been used as templates. Surfactant molecules... 

Fig. 2.17 X- ray characterization of the nano-scale structure for example PUs, plotted as crystallinity index (y) versus SAXS peak areas filled symbols — data for MDl-based polymers open symbols — data for DBDl-based polymers [175]...

Figure 8.4. (a) Initial configuration of a small Pt nanocluster deposited on a static graphite substrate in the presence of Nafion backbones, sidechains, water, and hydronium ions, (b) Pt-Pt radial distribution function for one-cluster systems compared to that of a two-cluster simulation set-up. (Reprinted from Cheng CH, Malek K, Djilah N. Investigation of Pt cluster size effects on the nano-scale structure of PEMFC catalyst layers, internal report, 2007, NRC-IFCI). 

TEM, SEM analysis. High-Resolution Transmission Electron Microscopy (HRTEM) is one of the effective techniques to study the sub-microscopic structure of solid materials. They can observe nano-scale structure of microcrystalline and its defects, the pore structure of zeolite, as well as layered materials. All these information can be hardly provided by other equipments. 

Figure 7.4. (a) Visualizing the interphase considering only the micro-scale. Interphase is a continuum layer with a gradient of properties reflecting variations in its structure. The main role of the micro-scale interphase is to provide stable and effective ineans for stress transfer between inclusions and polymer matrix even under adverse conditions, (b) Visualizing the structure of a micro-composite considering also the nano-scale structural features when the discrete structure of the matrix and inclusions becomes evident [169]... 

Jung S Y Yoshida H. Nano-scale structure change of amphiphilic di-block copolymer by blend. J Therm Anal... 

In order to prove the superhydrophobic and self-cleaning effect of textile products, ITV issues the quality mark self-cleaning - inspired by nature that makes use of the foregoing testing methods (Eig. 15.13). Additionally, in the testing procedure to this seal of approval the fiber s filament surface is examined with an SEM to qualify the surface structures, underlining the prerequisite of nano-scaled structures for the self-cleaning effect. 

K. Higashi, "Deformation Mechanisms of Positive Exponent Superplasticity in Advanced Aluminum Alloys with Nano or Near-Nano Scale Grained Structures," in Materials Science Forum Vols. 170-172, pp. 131-140, T.G. Langdon ed., Trans Tech Publications, Switzerland, (1994). 

TFL is an important sub-discipline of nano tribology. TFL in an ultra-thin clearance exists extensively in micro/nano components, integrated circuit (IC), micro-electromechanical system (MEMS), computer hard disks, etc. The impressive developments of these techniques present a challenge to develop a theory of TFL with an ordered structure at nano scale. In TFL modeling, two factors to be addressed are the microstructure of the fluids and the surface effects due to the very small clearance between two solid walls in relative motion [40]. 

Other key features in the analysis of pore structure are the length scales associated with the various micro- (nano)-scale obstacles and pores, the possible larger-scale variations in structure, and the averaging domain over which information is needed [6,341,436], The hterature refers to analysis of homogeneous and heterogeneous porous media, where homogeneous refers to media with no variation in physical properties (e.g., porosity, diffu-... 

Sakai, S., Nakanishi, S. and Nakato, Y. (2006) Mechanisms of oscillations and formation of nano-scale layered structures... 

Sadeghzadeh H, Morsali A, Yilmaz VY, Buyukgungor O (2010) Sonochemical synthesis of nano-scale mixed-ligands lead(II) coordination polymers as precursors for preparation of PbO and PbBr(OH) nano-structures thermal, structural and X-ray powder diffraction studies. Ultrason Sonochem 17(3) 592-597... 

A.D. Stefanis and A.A.G. Tomlinson, Scanning Probe Microscopies From Surface Structure to Nano-Scale Engineering, Trans Tech Publications Ltd., Uetikon-Zurich, 2001. 

MJ. Schoning, M.H. Abouzar, S. Ingebrandt, J. Platen, A. Offenhauser, and A. Poghossian, Towards label-free detection of charged macromolecules using field-effect-based structures scaling down from capacitive EIS sensor over ISFET to nano-scale devices, in Mater. Res. Soc. Symp. Proc. 915, 0915-R05-04 (2006). 

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