Synthesis and fungicidal activity of acetyl substituted benzyl disulfides

The synthesis and fungicidal activity of acetyl substituted benzyl disulfides 1(a – g) are reported. The compounds were characterized by elemental analysis, nuclear magnetic resonance (1H NMR and 13C NMR) and mass spectrometric techniques. The results of the biological screening showed that the synthesized compound possess very high fungicidal activity. KEY WORDS: Acetyl substituted benzyl disulfides, Fungicidal activity  Bull. Chem. Soc. Ethiop. 2003, 17(1), 53-60

Performance Review of Selected Topology-Aware Routing Strategies for Clustering Sensor Networks

In this paper, cluster-based routing (CBR) protocols for addressing issues pertinent to energy consumption, network lifespan, resource allocation and network coverage are reviewed. The paper presents an indepth  performance analysis and critical review of selected CBR algorithms. The study is domain-specific and simulation-based with emphasis on the tripartite trade-off between coverage, connectivity and lifespan. The rigorous statistical analysis of selected CBR schemes was also presented. Network simulation was conducted with Java-based Atarraya discrete-event simulation toolkit while statistical analysis was carried out using MATLAB. It was observed that the Periodic, Event-Driven and Query-Based Routing (PEQ) schemes performs better than Low-Energy Adaptive Clustering Hierarchy (LEACH), Threshold-Sensitive Energy-Efficient Sensor Network (TEEN) and Geographic Adaptive Fidelity (GAF) in terms of network lifespan, energy consumption and network throughput.Keywords: Wireless sensor network, Hierarchical topologies, Cluster-based routing, Statistical analysis, Network simulatio

<b>Polycyclic aromatic hydrocarbons in municipal waste ashes from three waste dumps in Lagos, Nigeria</b>

The levels of isolated polycyclic aromatic hydrocarbons (PAH) in ash residues of wastes from some major waste dumps in Lagos, Nigeria, were determined. The total amounts of the PAH in the ashes were in the range of 0.06 – 0.4 &mu;g/g. The ash from the waste dump that contains the highest level also displayed greatest variety of PAH