Colloidal processing of polymer ceramic nanocomposite integral capacitors

Polymer ceramic composites form a suitable material system for low temperature fabrication of embedded capacitors appropriate for the MCM-L technology. Improved electrical properties such as permittivity can be achieved by efficient filling of polymers with high dielectric constant ceramic powders such as lead magnesium niobate-lead titanate (PMN-PT) and barium titanate (BT). Photodefinable epoxies as the matrix polymer allow fine feature definition of the capacitor elements by conventional lithography techniques. The optimum weight percent of dispersant is tuned by monitoring the viscosity of the suspension. The dispersion mechanism (steric and electrostatic contribution) in a slightly polar solvent such as propylene glycol methyl ether acetate (PGMEA) is investigated from electrophoretic measurements. A high positive zeta potential is observed in the suspension, which suggests a strong contribution of electrostatic stabilization. By optimizing the particle packing using a bimodal distribution and modified processing methodology, a dielectric constant greater than 135 was achieved in PMN-PT/epoxy system. Suspensions are made with the lowest PGMEA content to ensure the efficiency of the dispersion and efficient particle packing in the dried film. Improved colloidal processing of nanoparticle-filled epoxy is a promising method to obtain ultra-thin capacitor films (<2/spl mu/m) with high capacitance density and improved yield. Capacitance of 35 nF/cm/sup 2/ was achieved with the thinnest films (2.5-3.0 /spl mu/m).     

Real time flood disaster monitoring based on energy efficient ensemble clustering mechanism in wireless sensor network

In this article, energy efficient ensemble clustering method (EECM) with black widow optimization (EECM-BWO) algorithm is proposed for effective data transmission with the help of real time flood disaster monitoring wireless sensor network (WSN). Initially, unified scalable ensemble clustering algorithm based on ensemble generation and consensus function is proposed for selecting the optimal routing path among the node using BWO algorithm. Then, biologically inspired routing black widow spiders optimization algorithm is proposed to trade off the nodes energy level, self-organization, and self-configuration in the WSN. The simulation is performed using NS2 simulator for validating the performance of the proposed EECM-BWO method. Here, in node, low delay achieves 24.07%, 72.58%, 51.36%, 81.75%, 77.74%, high packet delivery ratio achieves 70.83%, 53.93%, 90.23%, 43.58%, 24.58%, low packet drop attains 77.93%, 72.76%, 61.56%, 51.87%, 34.35%, low energy consumption attains 75.9%, 52.94%, 65.81%, 58%, 41.2% compared with existing energy-efficient clustering approach consolidated game theory as well as dual-cluster-head mode for WSNs energy-aware clustering by cuckoo optimization approach (EECM-COA), energy-aware clustering-based routing using multi-path reliable transmission with routing and control board (EECM-RCB-MRT), adaptive repair algorithm with temporally ordered routing algorithms for flood control strategy (EECM-AR-TORA-FCS), passive multi-hop clustering algorithm (EECM-PMC), dynamic source routing protocol based on genetic algorithm-bacterial foraging optimization (DSR-GA-BFO).     

Microwave drying of mango ginger (Curcuma amada Roxb): prediction of drying kinetics by mathematical modelling and artificial neural network

Curcuma amada (Mango ginger) was dried at four different power levels ranging 315–800 W to determine the effect of microwave power on moisture content, moisture ratio, drying rate, drying time and effective diffusivity. Among the fifteen thin layer drying models considered for evaluating the drying behaviour, the semi‐empirical Midilli et al., model described the drying kinetics very well with R² > 0.999. Drying rate and effective diffusivity increased as the microwave power output increased. Activation energy was estimated by a modified Arrhenius type equation and found to be 21.6 kW kg^?1. A feed‐forward artificial neural network using back‐propagation algorithm was also employed to predict the moisture content during MW drying and found adequate to predict the drying kinetics with R² of 0.985.     

MILD HYDROCRACKING OF VACUUM GAS OILS TO IMPROVE FCC PERFORMANCE AND MAXIMIZE DISTILLATE YIELDS

A pilot plant study was conducted on mild hydrocracking of heavy vacuum gas oils derived from two different crude sources over a commercially available catalyst to determine the possibility of utilizing mild hydrocracker bottoms as fluidized catalytic cracking feedstock along with improved middle distillate yields. The mild hydrocracking experiments were conducted at 390°C, 60 kg/cm², 1.0/h liquid hourly space velocity and H₂/oil ratio of 390 l/l in a pilot plant trickle bed reactor using two catalyst beds for pretreatment and mild hydrocracking reactions. The experimental results showed that mild hydrocracking would result in valuable middle distillates with low sulphur and nitrogen content. With research octane number of 78, the naphtha obtained from mild hydrocracking was found to be a good blending stock for gasoline pool. The middle distillate fraction (140-370°C) obtained from mild hydrocracking product was found to have cetane number in the range of 48-54. The bottom product from mild hydrocracking of heavy vacuum gas oils was found to be a good feedstock for fluidized catalytic cracking unit because of its low sulphur, nitrogen and aromatic contents. The data obtained from pilot plant studies showed that the processing of mild cracker bottom in FCC unit would result in better quality fuels.     

Inhibition of Rhizomucor miehei and Candida rugosa lipases by D-glucose in esterification between L-alanine and D-glucose

A detailed kinetic study of the esterification of D-glucose with L-alanine catalyzed by lipases from Rhizomucor miehei (RML) and Candida rugosa (CRL) showed that both lipases follow the Ping-Pong Bi-Bi mechanism, in which L-alanine and D-glucose bind in subsequent steps releasing water and L-alanyl-D-glucose, with competitive substrate inhibition by D-glucose at higher concentrations leading to the formation of dead-end lipase.D-glucose complexes. An attempt to obtain the best fit of this kinetic model through curve fitting yielded good approximates of the apparent values of four important kinetic parameters: for RML-k(cat)=0.29+/-0.028x10(-3) M h(-1) mg(-1), K(m L-alanine)= 4.9+/-0.51x10(-3) M, K(m D-glucose)=0.21+/-0.018x10(-3) M, and K(i D-glucose)=1.76+/-0.19x10(-3) M; for CRL-k(cat)= 0.75+/-0.08x10(-3) M h(-1) mg(-1), K(m L-alanine)=56.2+/-5.7x10(-3) M, K(m D-glucose)=16.2+/-1.8x10(-3) M, and K(i D-glucose) =21.0+/-1.9x10(-3) M.     

Effect of rotation on the heat penetration characteristics of thermally processed tuna in oil in retort pouches

Tuna in oil was processed in retort pouches (20 × 17 cm) to a, F₀ value of 10. Heat penetration characteristics were determined using a rotary retort to an F₀ value of 10 and the results compared with a stationary retort. For studying the changes in heat penetration during rotation, tuna in oil was packed into retort pouches, subjected to different rotation speeds (2, 4 and 6 r.p.m.) and thermally processed to the same F₀ value. For the same F₀ value of 10, although there was a reduction in process time with increasing rotation speed up to 6 r.p.m., the magnitude of the reduction in processing time decreased with increase in speed of rotation. However up to 2 r.p.m. there was a considerable reduction in process time.     

REACTIVITY RATIO ESTIMATION IN COPOLYMERIZATION: A NEW ANALYSIS OF UNRESOLVED CONFLICTS

Using a stochastic approach, a fresh analysis has been provided to resolve the possible causes of the existing conflicts in the reactivity ratio estimation in copolymerization systems. The analysis provides some new clues regarding the inadequacy of a transient system (batch reactor) and suggests the use of a steady state operation (CSTR) as a more reliable method.     

Fluid catalytic cracking: Selectivity and product yield patterns

Fluid catalytic cracking, a common secondary process employed in the petroleum industry, is used to convert heavier feedstocks into products such as liquefied Petroleum Gas (LPG), motor gasoline, diesel etc. The present study focuses on developing a three lump fraction kinetic model to estimate the yield of C5 up to 370°C cut (motor gasoline and middle distillates). A Micro Activity Test (MAT) apparatus was used to estimate the parameters in the kinetic model. The study is useful in evolving a procedure to simulate plant performance using experimental data obtained in the MAT apparatus for a particular catalyst and feedstock in terms of the product yield pattern.     

Chemical and nutritional evaluation of chili (Capsicum annum) seed oil

Alkali-refined red chili (Capsicum annum) seed oil was analyzed for free fatty acids, iodine value, saponification value, peroxide value and fatty acid composition, and the values were found to be close to those of edible oils. The alkali-refined chili oil (5% of diet), alcohol-treated chili oil (5%) and a mixture of alcohol-treated chili oil and peanut oil (5%+5%) were fed to adult male albino rats in natural diets for eight weeks. Digestibility was normal in all experimental animals and was on par with the peanut oil control. Serum lipid levels in the group fed alcohol-treated chili oil were slightly high compared to those in groups fed alkali-refined chili oil and peanut oil. Liver structure revealed no abnormalities.     

Color vision research and trichromatic theory: A historical review.

"After more than a century of scientific research in color vision the trichromatic theory continues to face theoretical contradictions and unexplained facts. Trichromatic theories everywhere should rigorously examine the theory's basic assumptions, provide much more experimental data on the basic visual functions, and honestly ask themselves the question: should the theory be subject to drastic revision or should it be replaced by some other theory?" (PsycINFO Database Record (c) 2010 APA, all rights reserved)