introduction: during the thirty years ago noise pollution increased quickly in the urbane communities that motorcycles are chief sources of noise. the objective of this study is reduction of noise emitted from motorcycle exhaust, applying engineering design. materials and methods: in this pre-experimental study, current condition of noise emitted from motorcycle exhaust and physical parameters ...

The optimum arterial perfusion pressure during cardiopulmonary bypass (CPB) remains uncertain. A correlation in some form with the patients' resting pressure almost certainly exists. Temperature and hematocrit affect blood viscosity. The optimum perfusion pressure during aortic surgery will vary after the initiation of CPB resulting cooling, heating, and hematocrit changes. Poiseuille's Law was...

in this study fullerene functionalized using oleum (h2so4·so3), followed by the hydrolysis of the intermediate cyclosulfated fullerene as well as  an oxidizing agent was employed to functionalize the fullerenes. ruthenium was then added by the impregnation method or deposited on the functionalized fullerene. subsequent to this step, response surface methodology (rsm) was used to study the cumul...

In this study, the diffusivity and volumetric mass transfer coefficients for the extraction of β-carotene from crude palm oil using CO2 solvent in supercritical fluid were determined in the pressure range of 7.5-17.5 MPa and temperature range of 80-120 ºC. For this purpose, a statistical method was applied in order to minimize the number of experiments required. The volumetric ma...

in this paper, natural convection heat transfer over a vertical plate in a darcy porous medium saturated with a nanofluid subject to heat generation/absorption was theoretically studied. the governing partial differential equations were transformed to a set of ordinary differential equations using similarity transformations and solved using finite difference method. the influence of parametric ...

in this research the daily data of 69 climatic variables (wind direction, wind speed, dry temperature, wet temperature, maximum and minimum temperature, average daily temperature, precipitation, relative humidity, station level pressure, cloudiness, horizontal visibility, vapor pressure, …) of abumoosa synoptic station during the years 1362-1388 were studied. initially, a data base of variabl...

Enzymological studies at high hydrostatic pressure generally involve temperature, pH and pressure as variables, owing to the effect of adiabatic compression and the ionization volume of the buffer system. In the case of NAD dependent oxidoreductases this implies that the extinction coefficient of the coenzyme may be affected by p, T and pH, apart from the spectral change accompanying the redox ...

Designing and manufacturing the multiple jets simulator and experimental investigation of the multiple jets in crossflow at low velocity ratios have been studied Together with design and build a low-speed wind tunnel. A specific rake is used to determine the flow field pressure and changes in static pressure measured by pressure taps in the near field of the jets. There are generally three regi...