An experimental study was performed to estimate the forced convection heat transfer performance and the pressure drop of a single layer graphene (GNPs) based DI-water nanofluid in a circular tube under a laminar flow and a uniform heat flux boundary conditions. The viscosity and thermal conductivity of nanofluid at weight concentrations of (0.1 to 1 wt%) were measured. The effects of the velocity of flow, heat flux and nanoparticle weight concentrations on the enhancement of the heat transfer are examined. The Nusselt number of the GNPs nanofluid was enhanced as the heat flux and the velocity of flow rate increased, and the maximum Nusselt number ratio (Nu nanofluid/ Nu base fluid) and thermal performance factor was (1.45) and (1.24) respectively, by using (1wt%) concentration and q=6104W/m2 heat flux. Finally, an analysis of the thermal performance factor shows that the GNPs nanofluids could work as a good alternative conventional working fluid in thermal heat transfer applications.
Abstract This research investigates how activated carbon (AC) was synthesized from potato peel waste (PPW). Different ACs were synthesized under the atmosphere's conditions during carbonation via two activation methods: first, chemical activation, and second, carbon dioxide-physical activation. The influence of the drying period on the preparation of the precursor and the methods of activation were investigated. The specific surface area and pore volume of the activated carbon were estimated using the Brunauer–Emmett–Teller method. The AC produced using physical activation had a surface area as high as 1210 m2/g with a pore volume of 0.37 cm3/g, whereas the chemical activation had a surface area of 1210 m2/g with a pore volume of 0.34 c
... Show MoreWas expanded display high reflectivity of the spectral remote infrared (m j 14-8) adoption order Alcolmtin ????????? thickness optical northeastern quarter wavelength and compared with results of previous studies based Aldrashalhalah on Ndharah matrix distinctive amended and fall of light close to the vertical arrangement multilayer materials buffer and in thin films homogeneous and uniform properties deposited on germanium basis results showed that the best choice for governments and their kills to expand bandwidth high reflectivity is much easier for the infrared than the area visible in addition to the order of these stacks is the cornerstone of the filters other visual...
Magnesium hydroxide was used as flame inhibitor to increased flame resistance for tires .Magnesium hydroxide was adding with (5%,10%) weight percents to rubber master batch of tire and then exposed the resulting material to a flame generated from gas torch with (10 mm) exposure distance . Method of measuring the surface temperature opposite to the flame was used to determine the heat transferred through tire material. The results were obtained shows enhanced flame resistance for tire by added magnesium hydroxide and this resistance increased by increasing hydroxide Percentage .
In this work, N-hydroxy phthalimide derivatives (NHPID) were synthesized from the nucleuphilic substitution reactions of (NHPI) with different halides (alkyl halides, sulfonyl halides, benzoyl halides and benzyl halides). The products were distinguished using FTIR spectrum and Nuclear magnetic resonsnce (1H-NMR and 13CNMR), in addition to other characteristic methods such as sodium fution for sulfur determination. followed by measuring antibacterial (with different types of gram positive/gram negative bacteria) and antifungal activities of these compounds.
In the present work theoretical relations are derived for the efficiency evaluation for the generation of the third and the fourth harmonics u$ing crystal cascading configuration. These relations can be applied to a wide class of nonlinear optical materials. Calculations are made for beta barium borate (BBO) crystal with ruby laser /.=694.3 nm . The case study involves producing the third harmonics at X. =231.4 nm of the fundamental beam. The formula of efficiency involves many parameters, which can be changed to enhance the efficiency. The results showed that the behavior of the efficiency is not linear with the crystal length. It is found that the efficiency increases when the input power increases. 'I'he walk-off length is calculated for
... Show MoreIn this study, the adsorption of Zn (NO3)2 is carried out by using surfaces of malvaparviflora. The validity of the adsorption is evaluated by using atomic absorption Spectrophotometry through determination the amount of adsorbed Zn (NO3)2. Various parameters such as PH, adsorbent weight and contact time are studied in terms of their effect on the reaction progress. Furthermore, Lagergren’s equation is used to determine adsorption kinetics. It is observed that high removal of Zn (NO3)2 is obtained at PH=2. High removal of Zn (NO3)2 is at the time equivalent of 60 min and reaches equilibrium,where 0.25gm is the best weight of adsorbant . For kinetics the reaction onto malvaparviflora follows pseudo first order Lagergren’s equation.