The oxygenation processes for the organic compounds have great applications in fine organic fabrications. To speed up progress in the industrialization of such oxidation systems, a monometallic dioxomolybdenum (VI) bis-Schiff base complex (MoO 2 L 2 ) was synthesized through coordination of easily accessible 4-hydroxyiminophenol ligand (HL) with cis-MoO 2 2+ ion in an octahedral geometry. The structural conformation of MoO 2 L 2 and its coordinated ligand (HL) was determined using modern spectrophotometric tools. A heterogeneous catalyst (MoO 2 L 2 @ZnO−TiO 2 ) was successfully prepared by immobilization of MoO 2 L 2 on the surface of ZnO−TiO 2 nanostructured particles through the deprotonation of 4-OH group in its coordinated ligand. Various analytical techniques were used to examine the surface morphology and internal structure features of ZnO−TiO 2 and MoO 2 L 2 @ZnO−TiO 2 nanocomposites. To study the catalytic efficiency of MoO 2 L 2 and MoO 2 L 2 @ZnO−TiO 2 -based catalysts, they were employed in the oxygenation process of Ph 2 S (diphenyl sulfide) and MePhS (methylphenyl sulfide) using the most environmentally friendly oxidant (an aqueous H 2 O 2 ) under an aerobic environment. A high degree of selectivity was observed for the productivity of diphenyl sulfoxide (Ph 2 SO) and methylphenyl sulfoxide (MePhSO), with some contamination of overoxidation side products (Ph 2 SO 2 and MePhSO 2 ). The catalytic oxidative ability was not observably superior for the heterogeneous coated catalyst by ZnO−TiO 2 over its homogeneous one (MoO 2 L 2 ) due to the less redox activity of ZnO and TiO 2 nanoparticles in the catalytic cycles for the oxygen-transfer mechanism. Both catalysts were successfully recycled, in which the homogeneous catalyst sustained its high catalytic potential for up to three cycles, while the heterogeneous catalyst was able to be reused up to six times.

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Excessive phosphorus can cause eutrophication in water bodies and needs to be reduced in most wastewaters before being discharged into receiving waters. The excess biological phosphorus removal (EBPR) process has been shown to be an economical and environmentally compatible method for reducing phosphorus from wastewaters. Despite the complexity of EBPR mechanisms, appropriately designed and operated treatment plants can easily achieve phosphorus (P) removal as long as EBPR-available organic substrates such as short chain volatile fatty acids (VFAs) and an aerobic-anaerobic (respectively) reactor configuration are provided. Some factors and operating conditions, adversely affect the performance of EBPR plants. Available design and research information for the EBPR process were directly related to organic strength, solids and phosphorus content in wastewater. The success of excess biological phosphorus removal (EBPR) process is largely dependent on the characteristics of organic carbon present in wastewater. The COD and BOD 5 content of wastewater will also determine whether a phosphorus removal EBPR system is required. For this paper, the performance of EBPR was investigated using modified contact stabilization activated sludge pilot plant. The study involved the construction of pilot plant which was setup in Quhafa WasteWater Treatment Plant (WWTP), Al Fayoum, Egypt. Results showed average removal efficiencies of COD, BOD 5 and TP are 91%, 92% and 85% respectively.

Objectives: The present study was designed to determine the value of the blood flow velocity and hemodynamic changes in the extracranial vertebral arteries in adults with vertigo by using color flow Doppler ultrasonography. Material and Methods: Ninety-six adult patients with vertigo without definite otogenic causes (clinically and audiologically normal) were investigated by color flow Doppler ultrasonography. Electronystagmography was done to correlate its findings with those of vertebral arteries Doppler blood flow (VABF). Results: A significantly slow VABF was reported in the vertigo group when compared with the control group. Velocity of vertebral artery in 54.2% cases showed abnormal findings: a laterality in 29.2% and a low circulatory velocity in 25%. In 66.6% of cases the findings of Doppler and Electronystagmography are in agreement. Conclusion: Doppler ultrasonography is a recent valuable tool which gives useful information on VABF in the diagnosis of dizzy patients especially those who are clinically and audiologically normal.