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1

Relation of motion resistance torque and friction torque in the four stroke engine

Islam M. A., Babiak M., Kałużny J.

Journal of KONES

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2011

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Vol. 18, No. 2

185-189

EN

Friction resistance identification is indispensable to determine the results of engine modifications which goal was to improve the engine mechanical efficiency. Unfortunately measurement of the friction torque is very difficult to realize because in the total motion resistance torque of the combustion engine the friction torque is only a small part. Resistance torque connected with compression of working medium and also at higher engine speeds with inertia resistance is much higher than friction torque. As a result of research made on the engine test bed the course of resistance connected with realization of the thermodynamic cycle were defined. Sufficient accuracy of these courses allows making an attempt to evolve friction resistance signal from global resistance signal. In the paper comparison of the total motion resistance with results of friction resistance computer simulations for hydrodynamic lubrication of piston-cylinder liner kinematic assembly will be made. It is worth to emphasize that movement resistance researches were made at the serial engine with only slight modifications, which considerably restricts the possibility of diversified engine working conditions influence in relation to the actual engine. Further researches on complete movement resistance simulation of the combustion engine are intended to be realized in order to determine the realizability and probable range of desirable friction losses reduction. Promising results will allow designing the competitive engine relative to present tendencies of "ECOMATIC" engine operation system which was proposed for the first time by Volskswagen.

2

Adsorption Behavior of Reactive Dye from Aqueous Phase on Activated Carbon

Khan M. R., Rahman M. M., Mozumder M. S. I., Uddin M. J., Islam M. A.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 7

1365-1378

EN

The adsorption of a reactive dye (Procion Red) from aqueous solution onto activated carbon was investigated. The effect of contact time, pH, adsorbent dosage and temperature were studied. The equilibrium data were described well by both Langmuir and Freundlich isotherm model. The adsorption kinetics was tested for pseudo-first-order, pseudo-sec - ond order, intraparticle diffusion and unified approach kinetic models. The unified approach model de scribed the kinetic data in accor dance with the experimental data and the forward and backward rate constants were evaluated from the model fittings. The adsorption is highly pH dependent and adsorption efficiency in creases with the decrease in pH. Thermodynamic parameters of the adsorption process suggested that the process was endothermic. The adsorption capacity of regenerated activated carbon showed more than 70 percent recovery of the adsorption efficiency of the initial virgin adsorbent.

3

Uptake of phenol from aqueous solution by burned water hyacinth

Uddin M.T., Islam M.S., Islam M.A., Abedin M.Z.

Polish Journal of Chemical Technology

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2008

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Vol. 10, nr 2

43-49

EN

The potential of burned water hyacinth (BWH) for phenol adsorption from aqueous solution was studied. Batch kinetic and isotherm studies were carried out under varying experimental conditions of contact time, phenol concentration, adsorbent dosage and pH. The pH at the point of zero charge (pH(PZC)) of the adsorbent was determined by the titration method and the value of 8.8 š 0.2 was obtained. The FTIR of the adsorbent was carried out in order to find the potential adsorption sites for the interaction with phenol molecules. The Freundlich and Langmuir adsorption models were used for the mathematical description of adsorption equilibrium and it was found that the experimental data fitted very well to the Langmuir model. Maximum adsorption capacity of the adsorbent was found to be 30.49 mg/g. Batch adsorption models, based on the assumption of the pseudo-first-order and pseudo-second-order models, were applied to examine the kinetics of the adsorption. The results showed that kinetic data closely followed the pseudo-second-order model.

4

An improved method for the identification of an undeclared transboundary emission source.

Islam M.A., Dubey B.N.

Environment Protection Engineering

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2007

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Vol. 33, nr 4

67-74

EN

An improved model has been proposed for identifying a transboundary undeclared emission source. In this model, the sampling strategy consists in a simultaneous control of pollutants (of different chemical nature) from an inner-boundary (known) source and a transboundary (unknown) source. The merit of the present development in source identification lies in the consideration of a continuum atmospheric stability with the dispersion parameters, depending on the meteorological conditions as well as specific nature of the terrain. The theoretical analysis is based on the applicability of the Gaussian Plume model describing the dispersion of a pollutant from a known source.

PL

Przedstawiono udoskonaloną wersję modelu służącego do identyfikacji bliżej nierozpoznanego transgranicznego źródła emisji. Istotną zaletą tej wersji modelu jest rozpoznanie źródła emisji w zmiennych warunkach równowagi atmosfery z parametrami dyspersji zależnymi zarówno od warunków meteorologicznych, jak i od ukształtowania terenu. Podstawą teoretycznej analizy jest model Gaussowski opisujący dyspersję zanieczyszczeń ze znanego źródła emisji.