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With the thought of green tires and the need of replacing carbon reinforcing fillers with noncarbon silica filler, the effectiveness of silane surface modification on dispersion state, dynamic viscoelastic, hysteresis, and abrasion resistance of SBR vulcanizates filled with a hybrid of carbon black (CB)/nano SiO 2 is investigated. In situ surface modification of nano SiO 2 is carried out using bis-(γ-triethoxysilylpropyl)-tetrasulfide (TESPT), and various compounds with different ratios of CB/SiO 2 are prepared via a melt mixing process in an internal bath mixer. Scanning electron microscopy (SEM) and FT-IR spectroscopy revealed improved dispersion of silica and CB clusters with enhanced molecular interactions using in situ surface modification with 5 phr of TESPT is performed. Evidence for enhanced molecular interactions included lower dynamic loss (tanδ) and less hysteresis measured via dynamic mechanical thermal analysis (DMTA). Our results indicate that appropriate modification of silica allows partial replacement of carbon black with silica for production of eco-friendly rubber products.

A multidisciplinary intervention to reduce protein-energy malnutrition among children in rural areas was piloted in 3 provinces of the Islamic Republic of Iran. Based on an initial situation analysis, a range of interventions were implemented through local nongovernmental organizations, including nutrition, health and literacy education for mothers, improved growth monitoring and fostering rural cooperatives and income generation schemes. Malnutrition before and after the intervention [in 1996 and 1999] was assessed using anthropometric measurements of r and om samples of children aged 6-35 months in control and intervention areas. Three years into the intervention, all indicators of malnutrition had consistently decreased in all intervention areas and the prevalence of underweight and stunting was significantly lower. Control areas showed a mixed pattern of small increases and decreases in malnutrition indicators

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