Microstructure, intrinsic

Thus, fundamental questions remain about what controls the creep rates of SiC-based materials. What is the role of carbon, of solid solution dopants Do the stacking faults in P-SiC grains play a role Is the a-SiC microstructure intrinsically more creep resistant All of these questions remain to be answered. 

The evolution of spall in a body subject to transient tensile stresses is complex. A state of homogeneous tensile stress is intrinsically unstable and small perturbations in the material microstructure (microcracks, inclusions, etc.) can lead to the opening of voids and initiation of the spall process. 

Electroless CoNiMnP and CoNiP were examined as underlayers for electroless CoP by Matsubara et al. [82], The CoNiMnP has a c-axis orientation normal to the film plane, whereas the CoMnP has a low degree of orientation. The CoP was found to deposit with a microstructure resembling that of the underlayer. Very thick deposits (> 0.5 fim) resume the intrinsic structure of CoP (with a low degree of PO). These composite structures have been tested as vertical recording media. 

The stress of oxidized PS layers is always compressive. For porous oxides, values below 108 N nT2 are reported [Ba5], which is nearly one order of magnitude smaller than values of intrinsic stress generated by low-temperature thermal oxidation of bulk silicon. The compressive stress in OPS has successfully been used to lift up released mesoporous films and thereby fabricate 3D microstructures [La9],... 

The microstructure and imperfection content of coatings produced by atomistic deposition processes can be varied over a very wide range to produce structures and properties similar to or totally different from bulk processed materials. In the latter case, the deposited materials may have high intrinsic stress, high point-defect concentration, extremely fine grain size, oriented microstructure, metastable phases, incorporated impurities, and macro-and microporosity. All of these may affect the physical, chemical, and mechanical properties of the coating. 

With the evaluated site coverage and pore blockage correlations for the effective ECA and oxygen diffusivity, respectively, and the intrinsic active area available from the reconstructed CL microstructure, the electrochemistry coupled species and charge transport equations can be solved with different liquid water saturation levels within the 1-D macrohomogeneous modeling framework,25,27 and the cathode overpotential, q can be estimated. 

The intrinsic 3D interfacial curvature in compositionally asymmetric block copolymers provides extra degrees of freedom for the phase behavior in hexagonally structured microdomains. It is now well established that confinement of a cylinderforming block copolymer to a thickness other than the characteristic structure dimension in bulk, together with surface fields, can cause the microstructure to deviate from that of the corresponding bulk material. Surface structures in Fig. 1 are examples of simulated [57-59] and experimentally observed morphologies [40, 49, 60-62] that are formed in thin films of bulk cylinder-forming block copolymers. 

On the other hand, it should be realized that radical copolymerization at heterogeneous conditions offers additional unique opportunities not available in homogeneous (solution) copolymerization. These include the intrinsic possibilities of exploiting the heterogeneities of the reaction system to control the chemical microstructure of the synthesized copolymers, making possible new paradigms for synthesis and production of polymeric materials. In this contribution, we discuss some new synthetic strategies, which have been developed in recent years to provide effective control of the chemical sequences. 

Then, a survey of micro reactors for heterogeneous catalyst screening introduces the technological methods used for screening. The description of microstructured reactors will be supplemented by other, conventional small-scale equipment such as mini-batch and fixed-bed reactors and small monoliths. For each of these reactors, exemplary applications will be given in order to demonstrate the properties of small-scale operation. Among a number of examples, methane oxidation as a sample reaction will be considered in detail. In a detailed case study, some intrinsic theoretical aspects of micro devices are discussed with respect to reactor design and experimental evaluation under the transient mode of reactor operation. It will be shown that, as soon as fluid dynamic information is added to the pure experimental data, more complex aspects of catalysis are derivable from overall conversion data, such as the intrinsic reaction kinetics. 

The present work summarizes opportunities of using high-resolution synchrotron and standard xrd techniques for structural characterization as well as for investigations of structure-property-relationships. xrd will be used to determine quantitatively the phase content of morphotropic pzt. Temperature dependent measurements provide information about the phase transformation of morphotropic donor doped pzt ceramics and high-resolution synchrotron X-ray diffraction gives information about the extrinsic and intrinsic contributions to the electric field induced strain, xrd results are finally compared with electrical measurements to analyze the interactions among microstructure, phase content and properties. 

Numerical micromagnetics, which may be based either on the finite difference or finite element method, resolve the local arrangement of the magnetization which arises from the interaction between intrinsic magnetic properties such as the magnetocrystalline anisotropy and the physical and chemical microstructure of the material. The numerical solution of the equation of motion also provides information on how the magnetization evolves in time. The time and space resolution of numerical micromagnetic simulations is in the order of nanometers and nanoseconds, respectively. 

Behrens M, Furche A, Kasatkin I, Trunschke A, Busser W, Muhler M, Kniep B, Fischer R, Schlogl R. The potential of microstructural optimization in metal/oxide catalysts Higher intrinsic activity of copper by partial embedding of copper nanoparticles. ChemCatChem. 2010 2(7) 816-818. 

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