in this work, the characteristics of flow and heat transfer of a fluid containing nano particles of aluminum oxide with the water volume fraction (0.1-0.2-0.3)(v/v) percent of the reports. the overall heat transfer coefficient, heat transfer and the average heat transfer fluid containing nano water - aluminum oxide in a horizontal double pipe counter flow heat exchanger under turbulent flow con...

This study evaluated the toxicity of hexavalent and trivalent compounds of chromium to the pacu, Piaractus mesopotamicus, in acute exposures of 96 h through mortality and histopathological responses. Hexavalent potassium dichromate was more toxic than trivalent compounds of chromium chloride, chromium oxide and chromium carbochelate. Sufficient mortalities occurred only with potassium dichromat...

Solid oxide fuel cells are high temperature electrochemical devices for direct conversion of fuel and oxidant to electricity and heat. The high temperature and dual atmosphere creates challenges for the materials in solid oxide fuel cell stacks. In this thesis SOFC stack materials were studied and developed. SOFC stacks are assembled at room temperature, then heated up, conditioned and operated...

The oxygen evolution reaction (OER) is considered a major bottleneck in the overall water electrolysis process. In this work, highly active manganese oxide nano-catalysts were synthesized via hot injection. Facile surface treatment generated Mn(III) species on monodisperse 10 nm MnO nanocrystals (NCs). Size dependency of MnO NCs on OER activity was also investigated. Surprisingly, the partially...

Some compounds of hexavalent chromium are well-established carcinogens. Chromium enters mammalian cells in the hexavalent form and is reduced to chromium (III). Treatment of purified DNA with chromium (III) produces DNA-DNA interstrand crosslinks (DDC) which obstruct the progression of DNA polymerases in vitro. DDC were also detected in chromate-treated cultured normal human lung cells using th...

abstract in respect to nano-technological studies and physiological and biochemical lesions of these materials on aquatic animals, in this study we examine the toxicity effects of nano-zinc oxide (zno nps) on hematological indices of common carp (cyprinus carpio). lc50 of nano zinc oxide was determined according to the mortality at 24, 48, 72 and 96 hours, respectively. during separate experime...

The determination of chromium(VI) at high concentrations can be performed spectrophotometrically with 1,5-diphenylcarbazite. The standard determination methods for chromium(VI) in leather like DIN53314 or IUC 18 have a detection limit of 3mg/kg leather. However the detection limit is not enough for lower concentrations. There is a need for lower detection limits because public awareness of hexa...

Background: The presence of heavy metals in the environment especially in water supplies have caused many concerns because of their toxicity and non-degradability. Hexavalent Chromium (Cr) is one of the most toxic metals which is used in many industries, so it is essential to remove it from industrial wastewater. In this study, we made a comparison between different adsorption isotherms in the ...