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The morphology, thermal, mechanical, and dielectric properties of high-performance poly(etheretherketone)/ [Si.sub.3][N.sub.4] nanocomposites fabricated by hot pressing were investigated. It was found that the coefficient of thermal expansion (CTE) and dissipation factor decreased significantly with increasing [Si.sub.3][N.sub.4] content, whereas thermal stability was affected slightly. A nanocompo-site with 30 wt% [Si.sub.3][N.sub.4] exhibited about 45% and 23% decrease in CTE, below and above [T.sub.g], respectively. The glass-transition temperature ([T.sub.g]) was increased up to 20 C. Microhardness was improved by 20% at 10 wt% Si3N4 content and thereafter it improved slightly. Modified rule of mixture with β = 0.1 or Halpin-Tsai model with c = 4 fits well the microhardness. The dielectric constant and loss factor of the nanocomposites are quite low, and thermal stability is much higher compared with commercial products. Various models were also used to correlate CTE and dielectric constant. POLYM. ENG. SCI., 51:509-517, 2011. [C]2010 Society of Plastics Engineers, INTRODUCTION The high-performance plastic packages that have unique combination of light weight, good thermal stability, high thermal conductivity, high modulus, low coefficient of thermal expansion (CTE), and low dielectric constant [...]

In this communication, the concept of reverse flat plate collector has been used as a heating medium of air for the drying of agricultural products in a cabinet dryer. The reverse fiat plate absorber is a non-concentrating collector which can collect solar heat at high temperature unlike conventional nonconcentrating collectors. The thermal performance of the proposed dryer is analyzed by solving the various energy balance equations. An attempt has been made to optimize the vent area of the dryer for speedy flow of humid air from the drying chamber to the atmosphere. In order to have parametric studies, numerical computations have been carried out for a typical day in June for Delhi climatic conditions. The performance of this system is compared with that of conventional cabinet dryers. It is found that the reverse flat plate absorber dryer gives the better performance.

The roles of agonist-induced ionic currents in the esophageal smooth muscle were investigated in single opossum esophageal circular muscle cells. Single smooth muscle cell shortening and voltage clamp whole cell recordings indicate that caffeine- and carbachol-induced chloride and cation currents induce smooth muscle contraction via activation of calcium-activated potassium, chloride, and cation conductances.

Tyrosine kinase inhibitors reduce voltage-dependent calcium (Ca2+) currents and Ca2+ entry in rabbit colonic muscularis mucosae via nifedipine-resistant channels involved in refilling the intracellular stores. Ca2+ entry is enhanced through tyrosine kinase activation using agonists. Ca2+ release from the intracellular store elicits spontaneous transient outward currents (STOCs). Epidermal growth factor results in an increase in Ca2+ entry, STOCs, and a tyrosine phosphorylated protein of 60 kDa.

The examination of smooth muscle cells from the rabbit esophageal muscularis mucosae for the presence of the ATP-sensitive K+ channel and its inhibition by carbachol shows that carbachol suppression of K+ channel is via M3 receptor subtype and the signalling pathways involve Ca2+, protein kinase C and tyrosine. The presence of tyrosine kinases increases the chances of K (sub ATP) being significantly involved in cellular processes such as mitogenesis.

A three-dimensional viscous Navier-Stokes flow solver was used to predict core and bypass rotor performance and radial flow characteristics of a 4.6:1 bypass ratio, single-stage fan. The three-dimensional flow solver can handle several blade rows simultaneously and has the capability to include a downstream splitter. Results of the analysis are compared with experimental data obtained during rig testing of a modern high bypass single-stage turbofan in which rotor performance for both bypass and core streams was measured.