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71.
The effect of martensitic transformation on the debonding initiation in single shape memory NiTi wire–epoxy matrix composite was studied. Three different heat treatment cycles were performed in order to obtain wires with different transformation characteristics. The composite samples were prepared using NiTi wires and steel wire for comparison. The single-wire specimens were subjected to the pull-out test. The in situ observations of the interfacial debonding and sliding behaviour during the test were carried out.  相似文献   
72.
Imaging Race.     
Researchers have recently begun to use the tools of neuroscience to examine the social psychological responses associated with race. This article serves as a review of the developing literature in this area. It advances the argument that neuroscience studies of race have the potential to shape fundamental assumptions about race, and the interplay between social and biological processes more generally. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
The use of zinc oxide (ZnO) based intermediate reflector (ZIR) in micromorph solar cells using low pressure chemical vapor deposition (LPCVD) was investigated. The influences of deposition temperature and dopant gas concentration on grain size and lateral electrical conductivity measurements are presented. Further ZIR deposition conditions were then directly evaluated in micromorph solar cell devices. Their electrical performances were compared to reference cells and cells incorporating silicon oxide based intermediate reflector. It is shown that both reduced ZIR deposition temperature and increased total flow rate allow for better performing devices with increased shunt resistance, as further supported by lock-in thermography shunt imaging. Relative micromorph efficiency increase of above 7% is shown with thin ZnO layers, along with absence of loss or even small increase of total current in the whole structure compared to cells without intermediate reflector.  相似文献   
74.
One of the variables in phenol formaldehyde adhesive resin formulation is the addition of urea, which allows the resin manufacturer to manipulate both product functionality and cost. Nitrogen content can be used as a measure of the level of urea addition because most of the nitrogen present is derived from urea added at the end of the preparation process. Nitrogen analyses of a set of commercial oriented strandboard resins were first determined by combustion analysis. IR spectroscopic data were then collected and used along with the values for nitrogen content to generate predictive models. First, principal component analysis demonstrated the ability to separate resin mixtures from low to high nitrogen content. Partial least squares regression was then performed and gave excellent correlations between the measured and predicted nitrogen contents for a set of unrelated (test) resins and a set of mixtures prepared through combinations of resins with known nitrogen contents. Similar results were obtained on both a wet and dry mass basis. Given the flexibility of this instrumentation, such analyses could be placed in‐line for real time monitoring of resin applied during panel manufacturing. © 2007 Wiley Periodicals, Inc. JAppl Polym Sci 2007  相似文献   
75.
Lanthanide and actinide targets are prepared at the University of Mainz by molecular plating, an electrochemical deposition from an organic solvent, for heavy-ion reaction studies at GSI. To acquire information about deposition yield, target thickness, and target homogeneity, the following analysis methods are applied.With neutron activation analysis (NAA) the deposition yield and the average thickness of the deposited material is determined. We report on the analytical procedure of NAA performed subsequent to the molecular plating process.Scanning electron microscope (SEM) is used to determine the morphology of the target surfaces. In combination with energy dispersive X-ray spectrometer (EDS), we also could obtain qualitative information about the chemical form of the deposited material. So far, gadolinium, samarium, holmium, and uranium targets have been investigated with SEM/EDS.With radiographic imaging (RI), targets of uranium prepared by molecular plating and by vacuum vaporization are investigated. This method is suitable to obtain information about the spatial distribution, the homogeneity, and the thickness of the target layer deposition.  相似文献   
76.
We describe the use of Bayesian inference to include prior information about the value of the measurand in the calculation of measurement uncertainty. Typical examples show this can, in effect, reduce the expanded uncertainty by up to 85 %. The application of the Bayesian approach to proving workpiece conformance to specification (as given by international standard ISO 14253-1) is presented and a procedure for increasing the conformance zone by modifying the expanded uncertainty guard bands is discussed.  相似文献   
77.
78.
We present a direct raytracing method for implicitly described fluid surfaces that takes into account the effects of capillary solid coupling at the boundaries. The method is independent of the underlying fluid simulation method and solely based on distance fields. We make use of the closed-form solution of the meniscus shape at the fluid interface to achieve the effect of surface tension exerted by the solid object. The shape of the liquid at these boundaries is influenced by various physical properties such as the force of gravity and the affinity between the liquid and the solid material. We generate contact angles at the boundaries without the need for computationally intensive small-scale simulation. At render time, we combine the closed-form solution for a small-scale effect with the numerical solution of a large-scale simulation. Our method is applicable for any implicit representation of the fluid surface and does not require an explicit extraction of the surface geometry. Therefore, it is especially useful for particle-based simulations. Furthermore, the solution is guaranteed to yield the correct contact angle and, for certain scenarios, it delivers the entirely correct solution throughout the interface; even in general scenarios, it yields plausible results. As for an example, we implemented and tested the proposed method in the setting of a smoothed particle hydrodynamics (SPH) fluid simulation.  相似文献   
79.
Investigations of the aging behavior induced by high temperatures coupled with oxidizing atmosphere of model NO x storage systems Ba/Al2O3 and Ba/CeO2 are reported in this paper. The samples were prepared, calcined and exposed to temperatures between 500 and 1000 °C in air for 12 h for thermal aging. Samples were characterized with XRD, HRSEM, DSC-TGA-MS and BET analyses. In XRD investigations of all model systems calcined at 500 °C for 2 h, the NO x storage component was present in form of BaCO3. The release of CO2 as a result of the decarbonization of the NO x storage component at increased temperatures was verified by thermogravimetric investigations. In the case of Ba/Al2O3, already during calcination a partial reaction of the NO x storage component with Al2O3 resulting in the formation of barium aluminate was observed. In the model system Ba/CeO2 the decomposition of the barium carbonate started above 780 °C and the formation of a barium cerium mixed oxide was observed. The presence of the barium containing NO x storage component has a strong influence on the specific surface area of the model NO x storage systems. The morphology and crystallite size of CeO2 modified with the barium containing NO x storage component exhibited distinct changes compared to the unmodified oxide. The NO x storage efficiency determined by model gas tests of freshly prepared and engine aged model NO x storage catalysts correlates well with the above described observations.  相似文献   
80.
The paper outlines, how financial service providers can generate competitive advantages through innovative IT-support for their financial advisory processes. Therefore a generic concept for individualised financial advisory processes is enhanced by the consideration of tax and social contribution effects. This concept is operationalised for the important field of private retirement planning. Thus IT-support for the process of individualised advice is essential because of its high complexity and enables an individualised optimisation of customers’ portfolios. In cooperation with a German financial service provider this concept is already successfully implemented in a first release and will be extended and improved in the future.  相似文献   
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