In situ photoacoustic spectroscopic studies on heterogeneous catalysts under conditions of gas flow

An all-glass open photoacoustic cell through which gases can be passed without affecting the signal has been described. The cell has been characterized for various chopping frequencies and temperatures. Several heterogeneous catalytic reactions have been studied under conditions of gas flow at elevated temperatures and the potential application of this method in the field of heterogeneous catalysis has been pointed out. Communication No. 428 from the Solid State and Structural Chemistry Unit.     

E-Tanh: a novel activation function for image processing neural network models

Neural Computing and Applications - Artificial neural network (ANN) is one of the technologies used for emerging real-world problems. Activation functions (AF) are used in deep learning...     

Correlation between stability of a protein and its dipeptide composition: a novel approach for predicting in vivo stability of a protein from its primary sequence

Statistical analysis of 12 unstable and 32 stable proteins revealedthat there are certain dipeptides, the occurrence of which issignificantly different in the unstable proteins compared withthose in the stable ones. Based on the impact of these dipeptideson the unstable proteins over the stable ones, a weight valueof instability is assigned to each of the dipeptides. For agiven protein the summation of these weight values normalizedto the length of its sequence helps to distinguish between unstableand stable proteins. Results suggest that the in vivo instabilityof proteins is possibly determined by the order of certain aminoacids in its sequence. An attempt is made to correlate metabolicstability of proteins with features of their primary sequencewhere weight values of instability for a protein of known sequencecould thus be used as an index for predicting its stabilitycharacteristics.     

Effect of concentrated sulfuric acid and nitroethane on insoluble residues in acetylating medium of cellulose acetate prepared from low grade pulps

Cellulose acetate was prepared from locally available low grade pulps containing α‐cellulose in the range of 79–94%. The chemical and spectroscopic characterization confirmed the acetylation of all the cellulosic sources studied in the work. The effect of concentrated sulfuric acid as a catalyst and nitroethane as a solvent in the acetylation medium in reducing the insoluble residues was studied. The gravimetric analysis has indicated that these reagents reduce the insoluble residues. This was further confirmed by the optical microscopic photographs. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1765–1771, 2005     

An Investigation of Carbon Content and Consolidation Temperature on Microstructure and Properties of Hafnium Boride Ceramic

This paper discusses the use of Plasma Pressure Compaction to consolidate hafnium diboride powders. The effect of carbon addition on densification was studied. The influence of consolidation temperature on microstructure, density, and hardness of the bulk sample is presented. The interrelationship between microstructure and properties of the bulk sample are rationalized in light of the intrinsic influence of carbon content and the extrinsic influence of consolidation temperature.     

Room temperature cured polyurea-urethane propellant with unique mechanical properties

A polyurea-urethane propellant based on an NCO-terminated prepolymer, a diamine and a triol has been developed. This is a room temperature curing propellant which is case-bondable. This has been standardized at 3-kg level and then scaled upto grains of 300-mm diameter and 2250-mm length weighing 250 kg. This propellant has a tensile strength of about 4 kg/cm² and an elongation of 150 percent. Because of low cost, case bondability and room temperature curability this can be used in large solid boosters.     

Ontology‐based Grid resource management

Grid resources are typically diverse in nature with respect to their software and hardware configurations, resource usage policies and the kind of application they support. Aggregating and monitoring these resources, and discovering suitable resources for the applications become a challenging issue. This is partially due to the representation of Grid metadata supported by the existing Grid middleware which offers limited scope for matching the job requirements that directly affect scheduling decisions. This paper proposes a semantic component in conventional Grid architecture to support ontology‐based representation of Grid metadata and facilitate context‐based information retrieval that complements Grid schedulers for effective resource management. Web Ontology language is used for creating Grid resource ontology and Algernon inference engine has been used for resource discovery. This semantic component has been integrated with conventional Grid schedulers. Several experiments have also been carried out to investigate the performance overhead that arises while integrating this component with Grid schedulers. Copyright © 2009 John Wiley & Sons, Ltd.     

Electrochemical studies of heat-treated NiCrMoFeCoAl and NiCrMoFeCoAl-30%Cr3C2 HVOF coatings on T22 boiler steel

Herein, we present the corrosion behavior of NiCrMoFeCoAl and NiCrMoFeCoAl-30%Cr₃C₂ high-velocity oxy fuel (HVOF) coatings on the ASTM-SAE213-T22 boiler tube steel alloy. The samples exposed to molten salt (Na₂SO₄–60%V₂O₅) environment at 700℃ under thermocyclic conditions were investigated in conjunction with electrochemical techniques. The surface structures and morphologies of heat-treated samples suggest the extent of corrosion is least for the NiCrMoFeCoAl-30%Cr₃C₂-coated steel. Room-temperature electrochemical analysis of heat-treated samples demonstrate the good stability with NiCrMoFeCoAl-30%Cr₃C₂ layers on T22 steel at solid/liquid interface under neutral pH conditions. The potentiodynamic and impedance analyses reveal that the higher charge transfer resistance was observed for NiCrMoFeCoAl-30%Cr3C2-coated steel, followed by NiCrMoFeCoAl-coated steel and bare T22 steel. The chromium carbide containing the HVOF coating exhibit a highly dense layer and the metal chromites/chromates on the post-heat-treated coatings provide poor access for the electrolyte to base alloy and subsequently improve corrosion stability.     

ProRata: A quantitative proteomics program for accurate protein abundance ratio estimation with confidence interval evaluation

A profile likelihood algorithm is proposed for quantitative shotgun proteomics to infer the abundance ratios of proteins from the abundance ratios of isotopically labeled peptides derived from proteolysis. Previously, we have shown that the estimation variability and bias of peptide abundance ratios can be predicted from their profile signal-to-noise ratios. Given multiple quantified peptides for a protein, the profile likelihood algorithm probabilistically weighs the peptide abundance ratios by their inferred estimation variability, accounts for their expected estimation bias, and suppresses contribution from outliers. This algorithm yields maximum likelihood point estimation and profile likelihood confidence interval estimation of protein abundance ratios. This point estimator is more accurate than an estimator based on the average of peptide abundance ratios. The confidence interval estimation provides an "error bar" for each protein abundance ratio that reflects its estimation precision and statistical uncertainty. The accuracy of the point estimation and the precision and confidence level of the interval estimation were benchmarked with standard mixtures of isotopically labeled proteomes. The profile likelihood algorithm was integrated into a quantitative proteomics program, called ProRata, freely available at www.MSProRata.org.     

Dielectric and thermal response of poly[(vinylidene chloride)‐co‐acrylonitrile]/poly(methyl methacrylate) blend membranes

Poly(methyl methacrylate) was mixed with poly[(vinylidene chloride)‐co‐acrylonitrile] (Saran‐F) and lithium perchlorate in tetrahydrofuran to make polymer blend systems. Solvent‐free membranes with various blend ratios were prepared using a solution casting technique. Impedance analysis was used to study the electrical response of the polymer membranes, which shows that the 50:50 wt% blend ratio polymer membrane has a low bulk resistance and high dielectric constant at room temperature and hence high ionic conductivity. The dielectric behaviour was analysed using dielectric permittivity and electric modulus of the samples. The conductance spectra follow the universal power law variation. Structural analysis confirms the amorphous nature and functional group analysis confirms the miscibility. The decomposition temperature of the membranes was determined using thermogravimetric analysis. © 2014 Society of Chemical Industry