Microstructural developments in Mg-Ti-PSZ systems

The microstructure of titania-added Mg-partially-stabilized zirconia (PSZ) is dramatically influenced by thermal treatments. Effects of various sintering, heat-treatment and thermal shock cycling parameters on the microstructure of the Mg-Ti-PSZ system are described. Conditions favourable for the growth of needle-like Ti-rich reinforcements in highly thermalshock-resistant Mg-Ti-PSZ ceramics are identified. TiO₂ seems to play a catalytic role in the formation of Zr-rich networks during high-temperature (1700°C) sintering of the Mg-Ti-PSZ system, quite similar to those found in Mg-PSZ, heat-treated above 1300 °C.     

Influence of Montmorillonite Clay Content on Thermal,Mechanical, Water Absorption and Biodegradability Properties of Treated Kenaf Fiber/ PLA-Hybrid Biocomposites

Silicon - Nowadays, the starring attentions of the polylactic acid based composites are improved due to environmental awareness and diminution of petroleum oil. The bio-plastics were restricted to...     

A reduced reaction model for carbon CVD/CVI processes

Carbon-carbon composites are produced by chemical vapor deposition/chemical vapor infiltration (CVD/CVI) processes. Models of carbon-carbon composite production processes will help reduce production costs. Reliable process models must, however, include details of the gas phase kinetics in order to identify optimal conditions. We have combined detailed gas phase kinetics, surface kinetics, and a pore closure model to predict pore geometry changes with respect to time. To determine the dominant gas phase kinetics, we reduced a large set of reactions to a minimal set using a sensitivity, rate, and dimensional analysis approach. These robust and relatively fast techniques can be used under a variety of conditions, including those within the pores of the composite. The process model shows that the deposition profile depends on the kinetic model chosen. Using the more realistic reaction model, conditions for uniform, or inside-out, densification can be suggested.     

Correlating the 3D melt electrospun polycaprolactone fiber diameter and process parameters using neural networks

In the present work, we developed an artificial neural networks (ANN) model to predict and analyze the polycaprolactone fiber diameter as a function of 3D melt electrospinning process parameters. A total of 35 datasets having various combinations of electrospinning writing process variables (collector speed, tip to nozzle distance, applied pressure, and voltage) and resultant fiber diameter were considered for model development. The designed stand-alone ANN software extracts relationships between the process variables and fiber diameter in a 3D melt electrospinning system. The developed model could predict the fiber diameter with reasonable accuracy for both train (28) and test (7) datasets. The relative index of importance revealed the significance of process variables on the fiber diameter. Virtual melt spinning system with the mean values of the process variables identifies the quantitative relationship between the fiber diameter and process variables.     

Memory leak detection in Plumbr

Platforms with automatic memory management, such as the JVM, are usually considered free of memory leaks. However, memory leaks can happen in such environments, as the garbage collector cannot free objects, which are not used by the application anymore, but are still referenced. Such unused objects can eventually fill up the heap and crash the application. Although this problem has been studied extensively, nevertheless, there are still many rooms for improvement in this area. This paper describes the statistical approach for memory leak detection, as an alternative, along with a commercial tool, Plumbr, which is based on the method. The tool is later analyzed with three case studies of real applications and in the process also analyzes strengths and weaknesses of the statistical approach for memory leak detection. Copyright © 2014 John Wiley & Sons, Ltd.     

Radon exhalation rate measurement in the environment of Hassan district of southern India

The radon exhalation rate from soil and building materials collected from the Hassan district of southern India was studied by the sealed can technique. The surface exhalation rates of the building materials were found to vary from 13.07 ± 0.19 to 430 ± 9 mBq m^–2 h^–1 with a mean value of 141 ± 4 mBq m^–2 h^–1. The surface exhalation rates of the soil samples were found to vary from 36.5 ± 0.8 mBq m^–2 h^–1 to 376 ± 7 mBq m^–2 h^–1 with a mean value of 140 ± 4 mBq m^–2 h^–1. Good positive correlation was observed between the effective radium content and radon exhalation rate for both soil and building materials. Annual effective dose and α-index have also been estimated for the population of the region.     

Impact of Zinc oxide nanoparticles on eggplant (S. melongena): studies on growth and the accumulation of nanoparticles

The increasing use of nanoparticles and their occurrence in the environment has made it imperative to elucidate their impact on the environment. Although several studies have advanced the authors’ understanding of nanoparticle–plant interactions, their knowledge of the exposure of plants to nanoparticles and their effects on edible crop plants remain meager and is often paradoxical. The aim of this study was to increase their knowledge on the effect of zinc oxide (ZnO) nanoparticles on eggplant seed germination and seedling growth. ZnO nanoparticles had a negative effect on the growth of eggplant in plant tissue‐culture conditions, as the growth of seedlings decreased with the increase in the concentration of ZnO nanoparticles. In contrast, ZnO nanoparticles enhanced eggplant growth under greenhouse conditions. The accumulation of ZnO nanoparticles in various parts of eggplant was observed through scanning electron microscopy of both plant tissue‐culture and greenhouse‐raised eggplant seedlings. To the best of their knowledge, this is the first study to report on ZnO nanoparticle accumulation in eggplant and its effect on seed germination and seedling growth.Inspec keywords: crops, zinc compounds, scanning electron microscopy, II‐VI semiconductors, nanoparticles, agriculture, cellular biophysics, nanofabricationOther keywords: plant tissue‐culture, greenhouse‐raised eggplant seedlings, ZnO nanoparticle accumulation, seedling growth, ZnO nanoparticles, nanoparticle–plant interactions, zinc oxide nanoparticles, eggplant seed germination, eggplant growth, ZnO     

Effect of CuO on the sintering and cryogenic microwave characteristics of (Zr0.8Sn0.2)TiO4 ceramics

The effect of CuO on the sintering temperature, microstructure and microwave dielectric properties of (Zr_0.8Sn_0.2)TiO₄ (ZST) modified with 1 wt% of ZnO has been investigated. Microwave dielectric properties of ZST ceramics are measured from cryogenic to room temperatures (15–290 K). Crystallite sizes of sintered ZST ceramics as derived from XRD are in the 30–50 nm range. The addition of CuO effectively reduced the sintering temperature to 1300 1C, possibly due to liquid-phase effects. Addition of CuO did not cause any secondary phases up to 1.5 wt% of CuO. The dielectric constant (ε_r) and temperature coefficient of resonant frequency (ε_f) of ZST ceramics do not significantly vary with temperature, whereas the unloaded quality factor (Q_u) changes noticeably. It is found that the Q_u factor of the sample without CuO decreased with increase in temperature, whereas the samples with addition of CuO up to 1.0 wt% showed less dependence on temperature. The Q_u factor of CuO-free ZST is 15,000 and that of ZST with 0.5 wt% of CuO is 11,800 at 15 K. The Q_u factor while measured at room temperature ranged between 2900 and 7000. Efforts were made to understand whether the increase in Q_u factor at both cryogenic and room temperatures is the result of intrinsic or extrinsic factors.     

Distribution of <Superscript>210</Superscript>Pb in the surface sediments of major rivers of coastal Kerala,South India

The distribution of ²¹⁰Pb in the sediment samples of major rivers of coastal Kerala, namely, Bharathapuzha, Periyar, and Kallada, was studied systematically. The activity of ²¹⁰Pb was estimated through ²¹⁰Po by radiochemical separation and subsequent deposition on a silver disc. The α-activity was then counted using a ZnS(Ag) counter of 30% efficiency, and the activity was calculated. The mean activities of ²¹⁰Pb in the sediment samples of Bharathapuzha, Periyar, and Kallada rivers were found to be 13.5 ± 1.2, 89 ± 3, and 61 ± 2 Bq kg^–1, respectively. Good correlation was found between the ²¹⁰Pb activity and organic matter percentage and clay content for Periyar and Kallada rivers.     

Anticorrosion Potential of Flectofenine on Mild Steel in Hydrochloric Acid Media: Experimental and Theoretical Study

Journal of Failure Analysis and Prevention - The inhibition effect of Flectofenine on corrosion of mild steel in 1M HCl solution was investigated by using traditional weight loss method and...