Effect of titanium on the creep deformation behaviour of 14Cr-15Ni-Ti stainless steel

14Cr-15Ni-Ti modified stainless steel alloyed with additions of phosphorus and silicon is a potential candidate material for the future cores of Prototype Fast Breeder Reactor. In order to optimise the titanium content in this steel, creep tests have been conducted on the heats with different titanium contents of 0.18, 0.23, 0.25 and 0.36 wt.% at 973 K at various stress levels. The stress exponents indicated that the rate controlling deformation mechanism was dislocation creep. A peak in the variation of rupture life with titanium content was observed around 0.23 wt.% titanium and the peak was more pronounced at lower stresses. The variation in creep strength with titanium content was correlated with transmission electron microscopic investigations. The peak in creep strength exhibited by the material with 0.23 wt.% titanium is attributed to the higher volume fraction of fine secondary titanium carbide (TiC) precipitates.     

Simulation of excavations in jointed rock masses using a practical equivalent continuum approach

A simple practical equivalent continuum numerical model previously presented by Sitharam et al. (Int. J. Rock Mech. Min. Sci. 38 (2001) 437) for simulating the behaviour of jointed rock mass has been incorporated in the commercial finite difference programme fast Lagrangian analysis of continua (FLAC). This model estimates the properties of jointed rock mass from the properties of intact rock and a joint factor (J_f), which is the integration of the properties of joints to take care of the effects of frequency, orientation and strength of joint. A FISH function has been written in FLAC specially for modelling jointed rocks. This paper verifies the validity of this model for three different field case studies, namely two large power station caverns, one in Japan and the other in Himalayas and Kiirunavara mine in Sweden. Sequential excavation was simulated in the analysis by assigning null model available in FLAC to the excavated rock mass in each stage. The settlement and failure observations reported from field studies for these different cases were compared with the predicted observations from the numerical analysis in this study. The results of numerical modelling applied to these different cases are systematically analysed to investigate the efficiency of the numerical model in estimating the deformations and stress distribution around the excavations. Results indicated that the model is capable of predicting the settlements and failure observations made in field fairly well. Results from this study confirmed the effectiveness of the practical equivalent continuum approach and the joint factor model used together for solving various problems involving excavations in jointed rocks.     

<Emphasis Type="Italic">Trans</Emphasis>–<Emphasis Type="Italic">trans</Emphasis> Conjugated Linoleic Acid Enriched Soybean Oil Reduces Fatty Liver and Lowers Serum Cholesterol in Obese Zucker Rats

Conjugated linoleic acid (CLA) is a collection of octadecadienoic fatty acids that have been shown to possess numerous health benefits. The CLA used in our study was produced by the photoisomerization of soybean oil and consists of about 20% CLA; this CLA consists of 75% trans–trans (a mixture of t8,t10; t9,t11; t10,t12) isomers. This method could be readily used to increase the CLA content of all soybean oil used as a food ingredient. The objective of this study was to determine the effects of trans–trans CLA-rich soy oil, fed as a dietary supplement, on body composition, dyslipidemia, hepatic steatosis, and markers of glucose control and liver function of obese fa/fa Zucker rats. The trans–trans CLA-rich soy oil lowered the serum cholesterol and low density lipoprotein–cholesterol levels by 41 and 50%, respectively, when compared to obese controls. Trans–trans CLA-rich soy oil supplementation also lowered the liver lipid content significantly (P < 0.05) with a concomitant decrease in the liver weight in the obese rats. In addition, glycated hemoglobin values were improved in the group receiving CLA-enriched soybean oil in comparison to the obese control. PPAR-γ expression in white adipose tissue was unchanged. In conclusion, trans–trans CLA-rich soy oil was effective in lowering total liver lipids and serum cholesterol.     

Emulsification properties of sodium caseinate‐based conjugates with selected polysaccharides

Sodium caseinate (SC) was conjugated with polysaccharides, viz. maltodextrin (MD), pectin (P) and gum arabic (GA) at protein:polysaccharide weight ratio of 1:2, 1:1 and 2:1. The emulsifying properties and other relevant chemical properties of these conjugates were compared. The visible colour change, SDS‐PAGE analysis and available reducing groups confirmed greater conjugation in SC‐MD conjugate than the SC‐GA and SC‐P conjugates. SC‐P conjugate at the weight ratio of 1:2 exhibited the best emulsifying properties (emulsifying activity – 46.7%, emulsion stability – 7 days at 5 ± 1 °C storage) and had better solubility (33.5%) near the iso‐electric pH.     

Numerical analysis of defect formation during fabrication of high temperature polymer electrolyte membrane solutions

Previous studies have shown that defects like pin‐holes and air entrainment are common during polymer electrolyte membrane (PEM) manufacturing. For mass production of defect‐free membranes, an optimized manufacturing process is required. The objective of this work is to understand the nature of defect generation during the manufacturing process of high‐temperature PEM membranes and the factors influencing them. An extrusion process is simulated using a multiphase, laminar model using computational fluid dynamics (CFD) techniques. The effects of processing conditions on quality of the cast and pressure drop are analyzed. The results showed that for a constant inlet to substrate velocity ratio, both the substrate velocity and temperature will have an insignificant effect on the entrained air height. However, their effect on pressure drop is found to be substantial. Further, it is shown that the inlet velocity and slot gap width have significant effect on the entrained air height and pressure drop. POLYM. ENG. SCI., 2010. © 2010 Society of Plastics Engineers.     

Dynamics of nanotechnology patenting: An Indian scenario

Nanotechnology reflects the combination/interaction of knowledge which is interdisciplinary in nature. Exclusive monopoly over patents on nano-scale materials, devices and processes is a much sought after concept among technology based industries today. According to many scientists and theorists, this science can lead to solutions of some of the toughest problems faced by mankind and the list of patents on nano-scale materials, tools and processes is expanding at a phenomenal pace. Even India is among the top 20 nations in nanotechnology research as is evident by the number of patents filed each year. Trade regime of the world has brought into focus the ability to generate and secure IPR. The transformation has been rapid and in such a dynamic landscape it is vital to protect the intellectual property. With increasing private sector involvement in nanotechnology R&D, the need for a comprehensive framework for regulating nanotechnology IPRs will be pivotal to the commercial success of the technology. Hence, it becomes increasingly more and more important to learn the various issues in patenting of nanotechnology inventions and address these issues now so as to avoid any problems later. This paper discusses the various methodologies used in the developing countries and what can be done in India to protect the same keeping in mind the interests of various partners in the value chain of nanotech patent from lab to market.     

Red lesion in fundus image with hexagonal pattern feature and two-level segmentation

Multimedia Tools and Applications - Red lesion identification at its early stage is very essential for the treatment of diabetic retinopathy to prevent loss of vision. This work proposes a red...     

Phototherapeutic keratectomy versus alcohol epitheliectomy with mechanical debridement for superficial variant of granular dystrophy: A paired eye comparison

PurposeTo compare outcome of phototherapeutic keratectomy (PTK) and alcohol epitheliectomy with mechanical debridement for superficial variant of granular dystrophy.MethodCase report. A 7 year old girl with superficial variant of granular dystrophy with an visual acuity of 20/70 both eyes, underwent a simultaneous PTK in right eye (OD) and alcohol epitheliectomy with mechanical debridement in left eye (OS). Post operatively the visual acuity, refraction and corneal clarity were assessed.ResultsOn the first post-operative day uncorrected visual acuity was 20/50 in both eyes. At 2 weeks, vision improved to 20/40 with +2.50 ?2.00 × 180 in OD and +1.50 ?1.50 × 180 in OS. At 2 years, vision and refraction were 20/25 with +2.50 ?2.00 × 180 in OD and 20/25 with +1.25 ?1.50 × 170 OS respectively. There was early recurrence of the granular dystrophy.ConclusionThe visual outcomes of both PTK and alcohol epitheliectomy are similar for superficial variant of granular dystrophy. The hyperopic shift with PTK is a matter of concern. Alcohol epitheliectomy can be used in treatment of superficial corneal dystrophies where PTK is unavailable.     

EM Analysis of Metamaterial Based Radar Absorbing Structure (RAS) for MillimeterWave Applications

The EM performance analysis of a multilayered metamaterial based radar absorbing structure (RAS) has been presented in this paper based on transmission line transfer matrix (TLTM) method for millimeter wave applications. The proposed metamaterial-RAS consists of cascaded DPS and MNG layers of identical configurations. It exhibits extremely low reflection (< 42 dB) at 95 GHz and absorbs more than 95% power of incident wave over the frequency range of 90.4- 100 GHz without metal backing for both TE and TM polarizations. In view of aerospace applications, the reflection, transmission, and absorption characteristics of the proposed metamaterial-RAS are also studied at different incident angles (0°, 30°, and 45°) for both polarizations.     

Oxidative stability of alpha‐linolenic acid (ω‐3) in flaxseed oil microcapsules fortified market milk

The oxidative stability of α‐linolenic acid (ALA) was investigated in market milk fortified with flaxseed oil microcapsules. Milk was fortified at levels of 1, 2 and 3 g/100 mL using flaxseed oil powder, and optimised on the basis of sensory scores. No significant difference was observed between the control, 1 and 2 g/100 mL fortified milk samples. Therefore, 2 g/100 mL fortified milk was further evaluated for oxidative stability, fatty acids profile and sensory acceptability during 5 days of storage. The fortified milk was oxidatively stable and sensorially acceptable, retaining ~10.35% ALA, which indicated that 250 mL of milk could meet ~46% of the RDA for ω‐3 fatty acids.