Effect of anti-scale agents on the solubility of CO2 in seawater at temperatures of 60 to 90ºC and pressures of 1–2 bar

The objective of this work is to present experimental data that would show the effect of temperature, salinity, pressure and the presence of anti-scale additives on CO₂ solubility in seawater. The paper examines the solubility of CO₂ in real seawater and real seawater dosed with two different anti-scale additives. The study has been performed at temperatures between 60ºC and 90ºC and at pressures of 1 and 2 bar. To assess the effect of each anti-scale additive on CO₂ gas solubility varying doses, 2–10 ppm of anti-scale additive have been used. For the purpose of the experimentation an experimental rig has been designed to ensure adequate contact between the gas phase and the aqueous phase. The continuous quantitative analysis of CO₂ concentration flowing from the experimental rig was measured using a CM-5011 Carbon Coulometer. A mass balance was carried out to calculate the amount of CO₂ absorbed into solution; Henry’s law constant was then calculated.     

Antioxidant and anticholinesterase evaluation of selected Turkish Salvia species

Since Salvia species (Lamiaceae) have been recorded to be used against memory loss in European folk medicine, we herein examined in vitro anticholinesterase and antioxidant activities of 56 extracts prepared with petroleum ether, chloroform, ethyl acetate and methanol obtained from 14 Salvia species (Salvia albimaculata Hedge and Hub, Salvia aucheri Bentham var. canescens Boiss and Heldr, Salvia candidissima Vahl. ssp. occidentalis, Salvia ceratophylla L., Salvia cryptantha Montbret and Bentham, Salvia cyanescens Boiss and Bal., Salvia frigida Boiss, Salvia forskahlei L., Salvia halophilaHedge, Salvia migrostegia Boiss and Bal., Salvia multicaulis Vahl., Salvia sclarea L., Salvia syriaca L., Salvia verticillata L. ssp. amasiaca) growing in Turkey. The antioxidant activities were assessed by both chemical and enzymatic methods against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging and xanthine/xanthine oxidase (XO) system generated superoxide anion radical inhibition. Anticholinesterase effect of the extracts was tested against both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) at concentrations of 0.2 and 1 mg/ml using a microplate-reader assay based on the Ellman method. Most of the extracts did not show any activity against AChE at 0.2 mg/ml, while the chloroform extracts had noticeable inhibition against BChE between 47.7% and 74.7%. The most active extracts at 1 mg/ml for AChE inhibition were observed to be petroleum ether extract of Salvia albimaculata (89.4%) and chloroform extract of Salvia cyanescens (80.2%), whereas ethyl acetate extracts of Salvia frigida and Salvia migrostegia, chloroform extracts of Salvia candidissima ssp. occidentalis and Salvia ceratophylla, as well as petroleum ether extract of Salvia cyanescens were found to inhibit potently BChE (92.2%, 89.6%, 91.1%, 91.3%, and 91.8%, respectively). Particularly, the ethyl acetate and methanol extracts were observed to be highly active against both DPPH and XO. Our data indicates that nonpolar extracts of Salvia species for anticholinesterase activity and the polar extracts for antioxidant activity are worth further phytochemical evaluation for identifying their active components.     

Electrodiffusion characterization of non-Newtonian flow through packed beds

The limiting current technique, involving the cathodic controlled reduction of ferricyanide ions, has been used in order to characterize the axial dispersion and the solid-liquid mass transfer for a non-Newtonian shear thinning power-law fluid flowing through fixed beds of spherical and parallelepipedal particles. For each of the two phenomena, results corresponding to Newtonian and non-Newtonian power-law flow at low Reynolds numbers can be described by the same dimensionless equation for beds packed with particles of the same shape.This paper was presented at the Workshop on Electrodiffusion Flow Diagnostics, CHISA, Prague, August 1990.     

Feasibility of using various photovoltaic systems for window-type air-conditioning units under hot-arid climates

This paper reports on the feasibility of using various Photovoltaic (PV) systems namely; Grid PV (GPV), Stand-Alone PV (SAPV), Grid PV Wind (GPVW) and PV Wind (PVW) for supplying the power requirements of a window-type air-conditioning system or other small loads. It was found that the GPVW system is the best system to meet the load requirement of a window-type air-conditioning system under the climatic conditions of Oman with values ranging from $39,500 to $56,500 for the capital cost and $9,000 to $33,000 for the total net capital cost depending on the wind speed. These values are attractive for remote off grid applications.     

Insights into research on phytochemistry and biological activities of Prunus armeniaca L. (apricot)

Prunus armeniaca L. (Rosaceae) is an important medicinal edible plant species commonly known as “apricot”. Apricot is one of the most delicious and commercially traded fruits in the world. The plant is rich in mono- and polysaccharides, polyphenols, fatty acids and sterol derivatives, carotenoids, cyanogenic glucosides, and volatile components due to its appealing smell. P. armeniaca has been also investigated for various biological activities such as antimicrobial, antimutagenic, inhibitory activity against several enzymes, cardioprotective, anti-inflammatory and antinociceptive as well as antioxidant activity. Among these activities, antioxidant activity of apricot has been studied extensively and the plant displayed a high antioxidant effect in both in vitro and in vivo test systems. In this review, the relevant literature summary is given on phytochemistry and biological activity reports published on apricot. The literature survey for this review was performed using the key words “Prunus armeniaca and apricot” through the search Scopus, ScienceDirect, Pubmed, and Web of Science data bases between 1950 and 2010.     

Measurement of thermophysical properties of polyester cured with styrene in the range 300–450 K

A pulse method for the simultaneous determination of thermal diffusivity, α, specific heat capacity, C_p, and thermal conductivity, λ, are measured for a series of curing of polyester and styrene in the presence of 10, 20, and 30% carbon black in the temperature range 300–450 K. The results show a dependence of the above-mentioned properties on temperature and composition. The mechanism of heat transfer through the specimens is also discussed. © 1993 John Wiley & Sons, Inc.     

A pilot-plant study of the adsorptive micellar flocculation process: Optimum design and operation

A pilot-plant scale study of the adsorptive micellar flocculation (AMF) process is presented for the first time, and builds on the solid foundation provided by previous fundamental laboratory studies. A number of experimental tests were conducted to validate the feasibility of using an AMF pilot rig to remove phenol from aqueous effluent streams. Several key factors, including flocculation time, floc settling time, optimum air flow-rate for agitation, and flocculant dosage, were determined. Residual concentrations in treated water indicated a surfactant removal efficiency of 95–98%, and pollutant removal reached 78% in two stages of process operation. A strategy for the separate recycling of surfactant, flocculant and pollutant has already been developed. The present study has thus made further progress in developing, testing, validating and optimising the operating conditions of a pilot-scale process. As such, it has demonstrated the feasibility of scaling up from the bench-scale to a commercial, continuously operated unit.     

Quench detection of multiple magnet system

Magnet protection mandates the detection of any normal zone so that the magnet can be safely discharged. This is usually achieved by having a center voltage tap and two voltage taps at both ends of the windings. The voltage across the two sections of the winding is compared and balanced for inductance. Any voltage signal is then due only to the presence of a normal zone. This method is shown to be inadequate for mutually coupled magnet systems. As a solution to this problem a theory of voltage detection for mutually coupled magnets is presented along with a voltage detection circuit based on Gaussian elimination. The method is confirmed by experiment. Two equivalent solutions are presented which involve either additional voltage taps or the incorporation of dI/dt signals from the coupled magnets     

Fire performance and decay resistance of solid wood and plywood treated with quaternary ammonia compounds and common fire retardants

In this study, the fire performance and decay resistance of solid wood and plywood treated with quaternary ammonia compounds (didecyl dimethyl ammonium chloride (DDAC) and didecyl dimethyl ammonium tetrafluoroborate (DBF)) were compared with the performance of untreated control specimens and specimens treated with common fire retardants ((monoammonium phosphate (MAP), diammonium phosphate (DAP) and ammonium sulphate (AS)). Test specimens were treated with 1% and 4% (% m/v) aqueous solutions of the chemicals. The fire performance tests were the fire tube test (ASTM E 69) which measures mass losses in the specimens and the cone calorimeter test (ASTM E 1354) which measures mass loss, heat release rate, time for sustained ignition, effective heat of combustion, and specific extinction area. The results from the cone calorimeter tests were used to estimate the flame spread index (FSI) in the Steiner tunnel test (ASTM E 84). Heat release rates of the specimens treated with MAP, DAP, and AS were lower than those of both DDAC and DBF-treated specimens and the untreated control specimens. Compared with the untreated specimens, higher heat release rates were observed for the specimens treated with the quaternary ammonia compounds, DDAC and DBF. The estimates for the FSI for DDAC and DBF were for values equal to or higher than for the untreated control specimens. At higher concentration levels, MAP, DAP and AS were effective in decreasing initial contribution of heat release to potential fire. Decay resistance tests were done according to AWPA E 10 standard method using one brown-rot fungus and one white rot-fungus. Decay resistance tests revealed that solid wood specimens treated with DDAC and DBF showed resistance against the fungi tested, however, MAP, DAP and AS did not provide complete protection. While DBF and DDAC increased resistance of plywood specimens, high mass losses in plywood specimens treated with MAP, DAP and AS were obtained.