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61.
This review covers processes used to deposit adherent coatings on Mo. Coatings applied by electroplating, physical vapor deposition (PVD), chemical vapor deposition (CVD) and plasma spraying are covered. Processing techniques for preparing the substrates for deposition are emphasized and supported with data on adherence of the coatings.  相似文献   
62.
Sharp notches subject to remote axial compression suffer closure of the root. In this paper we address this, and determine a first-order approximation to the extent of closure based on the asymptotic solution for a semi-infinite notch. This is then applied to an edge notch, and it is shown that the extent of closure is very small indeed, and likely to be smaller by several orders of magnitude than the notch root radius in any practically realisable case. It also follows that the notch root plasticity present for real materials is likely to encompass this region, and that the ‘open’ notch solution may be used without loss of accuracy.  相似文献   
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The solution of a stochastic control problem depends on the underlying model. The actual real world model may not be known precisely and so one solves the problem for a hypothetical model, that is in general different but close to the real one; the optimal (or nearly optimal) control of the hypothetical model is then used as solution for the real problem.In this paper, we assume that, what is not precisely known, is the underlying probability measure that determines the distribution of the random quantities driving the model. We investigate two ways to derive a bound on the suboptimality of the optimal control of the hypothetical problem when this control is used in the real problem. Both bounds are in terms of the Radon–Nikodym derivative of the underlying real world measure with respect to the hypothetical one. We finally investigate how the bounds compare to each other.  相似文献   
67.
The electrochromic response of W03 thin films under electrochemical insertion from nonaqueous electrolytes of one of the three different ions: protons, lithium and sodium cations is reported. In spite of the common belief that the nature of the ion does not change the electrochromic effect, we show that the sample colouring and bleaching are dependent on the intercalant ion and on the insertion rate. The facile insertion of protons is responsible for the highest optical contrast and the quickest response time of this intercalation electrode. Lithium and sodium-intercalated electrodes do not show large optical difference from the proton-intercalated tungsten trioxide unless large charging currents are used. Subtle changes in electrochromic efficiency and in the optical contrast in the red part of the spectrum can be detected; these are larger for the sodium than for the lithium intercalant. According to our analysis, the slow insertion kinetics of Na+ and the formation of a new M x WO3 (M=Li, Na) compound is responsible for most of the observed differences.  相似文献   
68.
This paper presents an approach for enhancing the design phase of AUTOSAR models when security annotations are required. The approach is based on information flow analysis and abstract interpretation. The analysis evaluates the correctness of the model by assessing if the flow of data is secure with respect to causal data dependencies within the model. To find these dependencies an exhaustive search through the model would be required. Abstract interpretation is used as a trade-off between the precision and complexity of the analysis. The approach also provides annotated models without oversizing the set of annotations.  相似文献   
69.
The influence of the composition and synthesis method on the low-coverage adsorption properties of C5–C9 n-alkanes on ZSM-5 zeolites was studied using the pulse chromatographic technique at temperatures between 200 and 400 °C. Experiments were performed with materials having Si/Al ratios between 12 and 400, synthesized with and without an organic template. For all ZSM-5 samples, the Henry adsorption constants increase exponentially with the carbon number, while zero-coverage adsorption enthalpies increase in a linear way. With decreasing Al content, the Henry constants and adsorption enthalpies decrease. An increase in adsorption enthalpy of 10.1 kJ/mol per added –CH2– group is observed for an Si/Al ratio of 400, while an increase of 12.1 kJ/mol is found for an Si/Al ratio of 15. The contribution to the adsorption entropy per carbon atom depends on the ZSM-5 composition and varies between 11.2 and 14.4 J/(mol K). A significant effect of the synthesis method on the Henry constants, adsorption enthalpies and entropies is observed. All ZSM-5 samples synthesized using organic templates show the same unique relationship between adsorption enthalpy and entropy, different from that of zeolites synthesized without organic template.  相似文献   
70.
开阳堡根据周易八卦之形而建,运用八卦、风水学,选址在一个形如龟背的沿河高地上.街区规划有别于传统的以南北中轴线为南北大街的格局,而采用南北两条较对称的大街,与东西二条街形成"井"字型结构,把整个堡划分为九部分,称"九宫街".  相似文献   
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