Crystallographic Analysis of Martensite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel using EBSD

The crystallography of martensite formed in 0.2C-2.0Mn-1.5Si-0.6Cr steel was studied using the electron backscattered diffraction(EBSD) technique.The results showed that the observed orientation relationship(OR) was closer to that of Nishiyama-Wassermann(N-W) than Kurdjumov-Sachs.The martensite consisted of parallel laths forming morphological packets.Typically,there were three different lath orientations in a morphological packet consisting of three specific N-W OR variants sharing the same {111} austenite plane.A packet of martensite laths with a common {111} austenite plane was termed a crystallographic packet.Generally,the crystallographic packet size corresponded to the morphological packet size,but occasionally the morphological packet was found to consist of two or more crystallographic packets.Therefore,the crystallographic packet size appeared to be finer than the morphological packet size.The relative orientation between the variants in crystallographic packets was found to be near 60 /<110>,which explains the strong peak observed near 60 in the grain boundary misorientation distribution.Martensite also contained a high fraction of boundaries with a misorientation in the range 2.5-8.Typically these boundaries were found to be located inside the martensite laths forming sub-laths.     

Growth of one-dimensional Si/SiGe heterostructures by thermal CVD

The first results on a simple new process for the direct fabrication of one-dimensional superlattices using common CVD chambers are presented. The experiments were carried out in a 200?mm industrial Centura reactor (Applied Materials). Low dimensionality and superlattices allow a significant increase in the figure of merit of thermoelectrics by controlling the transport of phonons and electrons. The monocrystalline nanowires produced according to this process are both one-dimensional and present heterostructures, with very thin layers (40?nm) of Si and SiGe. Concentrations up to 30?at.% Ge were obtained in the SiGe parts. Complementary techniques including transmission electronic microscopy (TEM), selected area electron diffraction (SAED), energy dispersive x-ray spectroscopy (EDS), scanning transmission electron microscopy (STEM) in bright field and high angle annular dark field (HAADF STEM), and energy-filtered transmission electron microscopy (EF-TEM) were used to characterize the nanoheterostructures.     

System-on-chip design by proof-based refinement

Systems-on-chip (SoCs) and SoC architectures provide a collection of challenging problems related to specification, modelling techniques, security issues and structuring questions. We describe a design methodology integrating the event B method and characterized by the incremental and proof-controlled construction of SoC models. The essence of the methodology is the refinement of models, starting from system requirements and producing event B models for characterizing the system under development. The refinement is a unifying concept that ensures the consistency of the different models produced and our contribution is an illustration through a case study, namely a system for measuring the parameters of audio/video quality in the digital video broadcasting (DVB) set of digital TV standards. The first part is the derivation of an architecture of parameters from the document ETSI TR 101 290 and the validation of the architecture using invariants of B models. The second part is the proposal of B models of the SystemC scheduler and an instantiation of these abstract models of the simulation semantics by parameters of the SystemC codes automatically translated from the B models of the DVB system. Finally, the third part relies upon a proof-based methodology for deriving an operational semantics of a given system that is expressed by an event B model including invariant properties.     

On Joint Order Statistics in Correlated Nakagami Fading Channels

In this letter, the joint probability density function (pdf) of the order statistics for a set of correlated Nakagami-m fading channels is derived. This result is useful in analyzing the performance of a variety of diversity schemes which involve branch selection. The derivation also yields a computationally efficient method for obtaining the marginal pdf of the p-th order statistic for a set of correlated Nakagami-m fading channels.     

Solution of laue back reflection patterns of sapphire crystals using a computer technique

A computer algorithm for the rapid solution of Laue back reflection patterns of sapphire crystals is described, (although other hexagonal systems could be indexed with minor changes). Reflections of planes having indices (3, 3, 3) and lower are indexed without using Wulff nets, Greninger charts, and so forth. Any film to specimen distance may be used and the systematic errors associated with this measurement are minimized to determine its best value. The computational scheme compares the angles associated with the reflections from the X-ray patterns and the true interplanar angles which are calculated from the computer program.     

Analysis of nitrate and nitrite in foodstuffs: A critical review

A general review is presented of published methods for the determination of nitrate and nitrite levels in foodstuffs especially meat. Published methods show wide variations in techniques for extraction, clean-up (clearing) of extracts and final determinative steps and these are critically compared. The effect of interferences due to the presence of ascorbate, sulphite and phosphate together with the formation of a “meat blank” when nitrate is reduced to nitrite with spongy cadmium are discussed. Newer techniques based on the use of ion selective electrodes and automated techniques are outlined and the application of techniques such as amperometry, liquid chromatography, ion exchange and spectrophotometry are listed.     

The simultaneous determination of both the quantity and the fatty acid composition of the triglycerides in three to ten microliters of plasma

An integrated system using chromatography on silica gel-impregnated glass paper, an internal standard and gas-liquid chromatography (GLC) makes possible the isolation of triglycerides, the determination of triglyceride, fatty acid composition, and the quantitative determination of triglyceride. Recoveries are good and values for total triglyceride obtained by this system compare favorably with values obtained by application of the hydroxamate colorimetric method to the triglyceride eluate from silicic acid columns. The fatty acid composition of the cholesteryl ester (CE) fraction is obtainable at the same time by GLC of methyl esters prepared from the CE fractions which also appears as a distinct spot on these chromatograms. Also, a densitometric method is described for triglyceride determination by photometry of the charred spots obtained after chromatography on the gel-paper. Presented at the AOCS Meeting, Houston, April, 1965     

Conditioning and personality: A study of normal and neurotic subjects.

"Pavlov's concepts of excitation and inhibition were related to the dimension of introversion-extraversion in normal and neurotic subjects. Normal and neurotic subjects were conditioned, using the eyeblink and PGR reflexes. It was found that (a) anxiety states conditioned much better than hysterics, and (b) conditionability is related to introversion-extraversion and not to neuroticism." 37 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)