Archives-June... 

Preparation of ZnO nanorod based natural dye-sensitized solar cell is reported. Seed layers were deposited on glass / ITO substrates using dip coating method with zinc acetate dihydrate as starting material. ZnO nanorods were fabricated on induced seeds by hydrothermal method using hexamethylenetetramine as a precipitant and zinc nitrate as source at 90°C. The crystal structure, orientation and surface morphology were investigated by X-Ray diffractometer and Scanning Electron Microscopy. Optical properties were studied using UV-visible spectroscopy. Prepared ZnO nanorods were employed as wide band gap semiconductor to construct natural dye-sensitized solar cells. Various natural dyes, extracted from natural plants such as leaves and flowers were used as sensitizers for natural dye-sensitized solar cells. The fill factor and solar-light-to-electricity conversion efficiency were obtained.

Acute ischemic stroke is a major cause of long-term disability and the second leading cause of mortality worldwide. One of main parts of it pathogenesis is production of reactive oxygen species. The goal of this study was to evaluate the neuroprotective effect of the new xanthine derivative B-YR-2 (hydrazide of 1,3-dimethyl-8-N-benzylaminoxanthinyl-7-acetic acid), which demonstrated high antioxidant qualities in vitro, in comparison with thiotriazoline, mexidol and citicoline.. Injection of B-YR-2 compound to the rats with experimental stroke had the most pronounced neuroprotective effect. B-YR-2 increased number of glial cells and neurons in the cerebral cortex and stimulated their morphofunctional activity.

The use of non edible oils blend in direct injection diesel engine shows its potential to reduce or control the NOx emissions. Combustion analysis of non edible and non edible blends revealed that the blends had a shorter ignition delay than diesel alone, at both full and light load, and a lower premixed burn fraction at full load. However, the diffusion burn rates were similar. The shorter ignition delay due to high cetane number of non edible oil blends has been suggested as being one of the causes of NOx increase the peak pressure and temperature increase in flame temperature in either pre mixed or diffusion burn has been followed by subsequent increase in NOx emission. This was due to reduction of carbonaceous soot concentration. The performance characteristics of an engine such as brake thermal efficiency, brake specific fuel consumption, brake power and engine torque were not much affected, up to a blend of 20% with neat diesel. The Co and particulate emissions were found to be decreasing with the % increase in blend with a subsequent increase of NOx. Thus the blending of fuel is being limited to 20% in majority of cases to obtain optimum performance and emission characteristics. This paper suggests about by using various types of non edible oils as fuel and blends directly in diesel engines by modifying properties by injecting or Trans-esterification.

Policy is a plan of action agreed or chosen by a people; a principle or framework adopted which influences their belief, actions, and operations. Out of 20 million people who suffer from the disease globally, an estimated 8million live in Nigeria. Onchocerciasis has been a public health problem in Nigeria for over three decades leading to disabilities and loss of person-hours with its negative consequences on health and the economy. This article examined the state of onchocerciasis policy in Nigeria since inception. Continuous review and improvement on government policies, strategies, and programmes is a positive step towards attaining a Neglected Tropical Diseases (NTD) free world.

We report herein the use of Nickel acetyl acetonate [Ni(acac)₂] as a new catalyst for the one-pot Biginelli reaction coupling of ?-ketoester, aldehydes and urea (or thiourea) to afford the corresponding dihydropyrimidinones/thiones.

The transfer reactive power from production source to consumption areas during steady-state operating conditions is a major problem of voltage stability. Hence voltage stability enhancement margin is interrelated with Reactive power loss (RPL). In practical, the power system network has 80-90% inductive loads. When the loads are increased, the line currents are increased, reflecting to the increase in Reactive power loss. This will leads to voltage instability that means the power system gets closer to the instability point. Reactive power can be dispatched effectively to maintain acceptable voltage levels. Maintaining viable voltage levels are very important to avoid voltage collapse. The optimal allocation of a VAR compensator is implemented using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). These two algorithms are implemented considering its less memory requirement and inherent simplicity. Simulation is carried out by using MATLAB Software for IEEE 14 bus system and the results are presented and analysed.

One of the most sensitive features of the sheet metal forming is the elastic recovery during unloading called springback. Sheet metals are prone to some amount of springback depending on elastic deformation. Obtaining the desired size and design of die depends on the knowledge of the amount of this springback. So the accurate prediction of the springback is very important. The springback is affected by the factors such as sheet thickness, material properties, tooling geometry etc. In this paper the effect of various parameters such as sheet thickness, ratio of die radius to sheet thickness, strength coefficients on springback are studied. Also a Neural Network prediction model is prepared and the results of FEA and NN model are compared for springback.

A ciliate Coleps hirtus is primarily a member of the Prostomatea (Schewiakoff, 1896), subclass Hypotrichia. During the period two years Jan. 2007 to Dec. 2008 total number of 1626(677 in Jan. to Dec. 2007 and 947 in Jan. to Dec. 2008) samples was examined, the number of positive samples with Coleps sp. was 281. The percentage prevalence was 14.33 and 19.43 respectively. Morphologically it show barrel shaped body with number of rectangular peculiar calcareous plates and three spinous processes at the posterior side. The characters help to understand this species even in swimming condition.

The study undertaken the explored the factors of Quality of working-life experiences in organizations. The factor analysis of the component ‘quality of working-life experiences’ led to the extraction of the factors from various organizations. The most points were “Career Growth”, “Work Stress” and “Job Satisfaction”. The results indicate that these factors have substantial roles to play in satiating the needs of the employees and how at middle managerial level different aspects are valued and employed for developing a unique and inimitable quality of working life within their socio-technical systems for eliciting favorable job-related responses.

A brief review of the structural reliability design methodology and its applications at system level are compiled from various sources. The main objective of this study is to present the developments in the reliability based analysis and design of land based structures, marine structures specially a diaphragm wall of a berthing structures. The present paper discusses right from the basic concepts of risk, reliability, safety and the methodologies to define reliability in a quantitative manner to aid to design a structure for a given reliability and the reliability concepts applied to aging structures, creep, shrinkage and serviceability, application of reliability analysis in other fields such as geotechnical engineering, design of marine structures, etc.,. To avoid unforeseen failure, the structural designs often undertake the concept of a safety factor to reduce the probability of failure or to increase the reliability. Analysis need to be carried out using Monte Carlo simulation assessing the partial factors, levels of risk and degree of uncertainty.