structural properties and chemical composition change the photocatalytic activity in tio2-sio2 nanopowder composite. the sio2-tio2 nanostructure is synthesized based on sol–gel method. the nanoparticles are characterized by x-ray fluorescents (xrf), x- ray diffraction (xrd), tunneling electron microscopy (tem), field emission scanning electron microscopy (fe-sem), uv-vis. spectrophotometer and ...

Bioremediation, the process by which microorganisms degrade organic compounds to non-toxic or less toxic substances, has been widely used for cleanup of coastal ecosystems after oil spills. In this study, the hydrocarbon degradation rate and half lives in three bioremediation strategies (natural attenuation, biostimulation, and bioaugmentation) were compared in weathered crude oil (WCO) contami...

Introduction: Advanced oxidation processes (AOPs) suggest a highly reactive, nonspecific oxidant namely hydroxyl radical (OH•), that oxidize a wide range of pollutants fast and non-selective in wastewater and water. Materials and methods: In this work, the nitrogen-doped titanium dioxide nanoparticles were primed by sol-gel method, characterized by X-ray diffraction and Scanning Elect...

this research evaluates the efficiency of nanosized zno in the catalytic ozonation of 4-chloro-2-nitrophenol and determines the effect of ph on heterogeneous catalytic ozonation. the combined use of ozone and zno catalyst leads to conversion of 98% 4-chloro-2-nitrophenol during 5 min. in addition, it was found that in zno catalytic ozonation, the degradation efficiency of 4-chloro-2-nitrophenol...

In a system, prediction of remaining useful lifetime (RUL) of servicing before reaching to a specified breakdown threshold is a very important practical issue, and research in this field is still regarded as an appreciated research gap. Operational environment of an equipment is not constant and changes regarding to stresses and shocks. These random environmental factors accelerate system deter...

In this study a solid dispersion and a physical mixture of cilazapril (CIL) with a biopolymer - polyvinylpyrrolidone (PVP) as a carrier were prepared so as to investigate the effect of PVP on the stability of CIL. CIL is unstable in solid state and decomposes rapidly under humid conditions. It requires stabilization to ensure safety of its use. The studied CIL/PVP formulations were prepared by ...

In this study a solid dispersion and a physical mixture of cilazapril (CIL) with a biopolymer - polyvinylpyrrolidone (PVP) as a carrier were prepared so as to investigate the effect of PVP on the stability of CIL. CIL is unstable in solid state and decomposes rapidly under humid conditions. It requires stabilization to ensure safety of its use. The studied CIL/PVP formulations were prepared by ...

Laboratory studies investigated the influence of dissolved oxygen tension (DOT) on microbial degradation of hexadecane in cultures with sediment-seawater suspensions. With a fermentor system, it was possible to adjust and regulate different oxic conditions (DOTs between 0.4 and 80% of oxygen saturation) as well as anoxia. The effects of DOT reduction on the amount and rate of hexadecane degrade...

in this study, the stability of trinitroglycerin (tng) in polyethylene (peg) 400 was investigated according to arrhenius approach. the reaction rate constant (k) for the thermal disintegration of tng in peg 400 at various temperatures was counted based on the percents of remaining tng at different intervals of time at a specific temperature. the results showed that “k” at 40, 50, 60, 70, 80 and...