The effect of partitioning single pass mesh wire packed bed solar air heater

Paper presented at the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Turkey, 19-21 July, 2010.Two single pass Solar air heaters (SAHs) having two and six fins (partitions) respectively were constructed and experimentally investigated The aim of the partitions is to increase the airflow path length. The path followed by the working fluid was increased due to increase in the number of partitions. Wire mesh layers were used within the partitions instead of an absorber plate. The effect of thermal partition on the thermal efficiency was investigated experimentally. The range of mass flow rate through the collectors is varied from 0.12 to 0.36 kg/s. Thermal efficiencies obtained for the two and six partitions were 80.6% and 83.1% respectively with a mass flow rate of 0.36 kg/s in each case. The maximum temperature differences obtained for the two and six partitions were 48.2 °C and 58.4 °C respectively with a mass flow rate of 0.12 kg/s in each case.ksb201

IgA nephropathy: A clinicopathologic study from two centers in Saudi Arabia

A total of 42 patients, who were diagnosed to have primary Immunoglobulin A neph-ropathy (IgAN) at the King Abdul Aziz University Hospital and King Faisal Hospital, Jeddah over the last seven years, were studied. The objective was to analyze their clinical and pathological fea-tures and to classify them according to Hass Classification by using light, immunofluorescence and electron microscopy. Majority of the study cases were males in the second, third and fourth decades of life. Hematuria was the most common clinical complaint followed by proteinuria. There were varying degrees of mesangial proliferation. Majority of the cases presented with class-2 followed by class-3. Immunofluorescence demonstrated diffuse granular deposition of IgA in the glomerular mesangium in majority of the cases. Ultrastructural analysis showed electron dense deposits within the matrix of the mesangium and paramesangium in majority of the cases. Sub-endothelial deposits and mesangial interposition were demonstrated in few cases. Extensive effacement with fusion of the visceral epithelial foot processes was detected in only few patients while focal effacement was demonstrated in many cases. Irregularities of the glomerular basement membrane were seen in some cases. We conclude that IgA nephropathy is an immune-complex glomerular disease, which occurs at all ages and with higher frequency in males and presents mostly with hematuria and proteinuria. Public health awareness is seriously needed to perform the investigations at an early stage

The effect of partitioning single pass mesh wire packed bed solar air heater

Paper presented at the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Turkey, 19-21 July, 2010.ej201

Kitab al-Jawahir al-Khams/ Muhammad Bin Khatir ad-Din Bayazid Khawajah al- Athar

512 hal.; 25 cm

Assessment of Heavy Metals in Greenhouse Cultivated Soils, Northern Jordan

Jordan has recently observed a gradual shift in vegetable production from open-fields to greenhouses with mounting consumer concerns about food quality and safety. We investigated heavy metals in soil collected from greenhouse vegetable production area in northern Jordan. Sixty-one surface soil samples were collected, of which forty-seven from plastic-covered greenhouses and fourteen were sampled from the adjacent open-field land, with both designated for vegetable production. The average concentrations of Cr, Cu, Cd, Pb, Ni, Zn were 26.1, 26.8, 0.81, 53.0, 49.3, 139.1 mg/kg, and 19.1, 19.3, 0.66, 49.7, 46.7, 104.9 mg/kg for greenhouse and open-field soils, respectively. While the accumulation of heavy metals was consistently higher in greenhouse than in open-fields, both soils revealed a similar metal ranking with a few exceptions. Greenhouse soils revealed relatively lower pH values with higher variabilities. In greenhouse cultivated soils, CaCO3 content averaged 21.4% compared to 23% measured in open-field soils. Soil salinity showed greater values for greenhouse samples (averaging 1118.6 µs/cm) than those observed in open-field agricultural soils (a mean of 503.6 µs/cm). The soil organic matter (TOM) exhibited values in the range of 1.06-3.35% relative to 0.59-2.41% found in open-field area. The spatial distribution of heavy metal concentrations for greenhouse soils revealed higher levels in the northern soils, whereas the least was found in the southern sampling points. The Enrichment results showed 23.4% of sampling sites were moderately contaminated with Pb, and 38.3% were moderately contaminated with Cd, of which 8.5% indicating moderately severe contamination. The Igeo results indicate 25.5% of greenhouse soils were moderately contaminated with Pb and 38.3% were heavily polluted with Cd. The contamination factors showed 25.5% and 38.3% of greenhouse sampling soils were considerably contaminated with Pb and Cd, respectively. 2% indicate very high contamination for Cd and 2% showed considerable contamination for Zn. PLI indicates that only two sampling sites are polluted. The ecological risk assessment showed low Ei values for all heavy metals suggesting slight risks, except for Cd which indicate strong risk. Total potential ecological risks values showed low risk to the local environment. Cd accounts for most of the total risks (72.27-82.67%) followed by Pb (11.49-14.87%). Some greenhouse soils were non-compliant with soil quality standards especially for Ni, Cd, and Pb. The observed levels of heavy metals are attributable to agricultural activities including long-term application of pesticides, phosphatic and nitrogen fertilizers, sewage sludge, wastewater irrigation and chicken manure in addition to industrial dust and traffic related emissions