Microstructure and Texture Development during Cold Rolling in UNS S32205 and UNS S32760 Duplex Stainless Steels

Metallurgical and Materials Transactions A - In the present study, microstructure and texture evolution during cold rolling in UNS S32205 and UNS S32760 duplex stainless steel was investigated....     

High speed architectures for Leviathan: a binary tree based stream cipher

Connectionless routed networks, built atop high-speed communication medium, require cryptographic algorithms capable of out-of-order keystream generation and high throughput. Binary tree based stream ciphers, of which Leviathan is an example, are capable of meeting both of these requirements. We investigate high-speed architectures for the binary tree traversal and show that the traversal approaches discussed can be extended to m-ary tree of height h. Of the two architectures presented, the pipeline architecture computes keystream at uniform rate and the parallel architecture bounds the worst-case variance in the time period between computations of consecutive output key words, which form the keystream. The design and implementation of Leviathan keystream generator based on the pipeline architecture for binary tree traversal are presented. We show that it is possible to achieve keystream generation rates approaching 1 Gbps with the pipeline architecture. The design was implemented in two parts, the keysetup and the keystream pipeline, targeting commercially available Xilinx XC2V4000 and XC2V3000 FPGAs. The keystream pipeline implementation operated at frequency of 50 MHz and occupied 6864 slices. The results were verified performing the timing simulation.     

Synthesis of Nanosized Ba2LaZrO5.5 Ceramic Powders through a Novel Combustion Route

A single-step process for the preparation of nanoparticles of Ba₂LaZrO_5.5 is reported in this paper. The process is a modification of the combustion method, which resulted in Ba₂LaZrO_5.5 phase without a calcination step. This complex perovskite ceramic oxide thus obtained is characterized by high-resolution transmission-electron microscopy, X-ray and electron diffraction, thermal analysis, FT-IR spectroscopy, surface area measurements, and particle-size analysis. The particle size of Ba₂LaZrO_5.5 was in the range 10–70 nm and were of regular shape with well-defined grain boundaries.     

Synthesis of vanillyl-maltoside using glucosidases by response surface methodology

Amyloglucosidase from Rhizopus mold and β-glucosidase from sweet almond, catalysed synthesis of vanillyl-maltoside was optimized using response surface methodology. A central composite rotatable design involving 32 experiments of five variables at five levels was employed. Among the variables employed, glucosidases (10–50% w/w of maltose), vanillin (0.5–2.5 mmol), incubation period (24–120 h), buffer volume 0.4–2.0 ml (0.04–0.2 mM) and pH (4.0–8.0); enzyme, buffer concentration and buffer pH were found to be significant with both the enzymes. Surface plots generated clearly brought out the maltosylation behaviour of the two glucosidases in this reaction with both the enzymes exhibiting yields in the range 5–60%. Saddle-shaped surface plots observed with both the enzymes exhibited total reversal of the maltosylation behaviour at certain critical crossover points like 30% (w/w maltose) enzyme concentration, buffer pH 6.0 and a buffer concentration of 1.25 ml (0.125 mM), implying that a critical enzyme to buffer concentration and pH dictate the extent of vanillin maltosylation. Validation experiments conducted at certain random selected conditions as well as those conducted at optimum conditions obtained from the reduced model showed good correspondence between predicted and experimental yields.