Archives-December 

We are very happy to announce that from 9th June 2018, Prof. Dr. Alireza Heidari has joined the team of Elixir Editorial Advisory Board. He/She will carry a special responsibility for dealing with manuscripts based on Chemistry. The appointment of Prof. Dr. Alireza Heidari as member Editorial Advisory Board strengthens the links and will make it easier for prospective authors to establish contact with the journal. Please send any expressions of interest to elixirpublishers@gmail.com.

A significant increase of the electrical equipment in modern aircrafts is leading to an increase in the demand for electrical power. The usual electrical power distribution in aircraft applications is done via a three-phase 415 Vac grid. A new trend of DC distribution is emerging employing a 270 Vdc grid. With the advancement in the power semiconductor devices and power transformers, DC-DC converters are designed with frequency ranging up to MHZ range. Increase in the switching frequency along with the sudden change in the current di/dt or voltage dv/dt generates higher order harmonics which leads to Electro Magnetic Interference (EMI). EMI noise creates malfunctioning of the circuit and also leads to miscommunication within the system and sometimes leads to device failure. Which is an undesirable condition as far as airline is considered. Hence the reduction of EMI noise is of uttermost important. This paper focus on the reduction of EMI using passive filter along with modified PWM carrier modulation technique. A circuit model for the prediction of conducted emissions due to DC/DC converters in an aircraft black box system is proposed and corresponding attenuation method is been analyzed.

The biosorption is an effective and versatile method and can be easily adopted in low cost to remove heavy metals from large amount of industrial wastewaters. The biocarbon obtained from medicinal plant called Ocimum sanctum (Lamiaceae) is considered as a cheap materials for the removal of lead ions for aqueous solution. From batch biosorption studies, the effect of pH, contact time, different concentration of Pb(II) ions were used to estimate the optimum biosorption conditions. Removal efficiency of the biocarbon for Pb(II) ion in aqueous solution is maximum (87.5%) at pH 5.5. The effective contact time is 150min and the optimum biocarbon dose is 2.5g/100ml. The results indicate that, the percentage removal of metal ion increases progressively with the increase in amount of biocarbon dose. The activated biocarbon Ocimum sanctum was investigated as a replacement for the current expensive methods of removing metal ions from aqueous solutions.

Piezoelectric materials appealing for use in smart structures as sensors and actuators instantaneously transform mechanical energy to electrical energy and contrariwise. They remember configurations and guarantee them when subject to stimulus, have superb electromechanical coupling characteristics and outstanding frequency response .Innumerous utilization of smart structures technology to diverse physical systems have progressed to actively control shape, aeroelastic stability, noise, damping, vibration and stress distribution. In this article the research activities of piezoelectric materials for smart structures is grouped into characterization, formulation, analysis, applications & debonding in aid in future research activities in any of the grouped class.

The role of parental support is crucial in building self-confidence among the teenagers. The present study examined the role of parental support in building self-confidence among the teenagers. The study was based on the purposive sample of 50 students taken from three schools in Islamabad namely, Roots, the City School and Scholanova. The ages of the students ranged between 13 to 19 studying in O’ levels and A’ Levels. The data thus gathered revealed that parental behavior exhibited in the form of care, control, autonomy and financial support are instrumental in building self-confidence among the teenagers but care proved more effective as compared to other factors with control, autonomy and financial support coming next respectively. The study observed the fathers and mothers of different professional backgrounds affect their parenting styles. Comparing fathers and mothers support, it was found that mothers are more careful and financially support than fathers whereas fathers’ support is significant in giving autonomy than mothers. Overall it was found that parental support based on caring and control play more effective role in building self-confidence among teenagers than autonomy and financial support.

This paper proposes an approach of adapting the vector space model with dependency parse relations to generate semantic summary from multiple documents. Traditional vector space models with tf-idf weighting was not able to completely capture the content similarity because it treats the words within a document are independent of each other. In the proposed system the dependency parse of the document has been used to modify the tf-idf weight of words by incorporating the dependency between each pair of words. To select relevant sentences, different combinations of features are applied through sentence ranking strategy. The experiment result shows that consistent improvement of proposed system over traditional approaches.

Sugarcane is one of the industrial crops used as raw material for several major and minor industries. In Khuzestan, which contains most of the sugarcane farms of Iran, sugarcane is harvested either in green or burnt method. Mechanized harvesting has been replaced by manual harvesting during recent years. Delay in milling of the harvested sugarcane is caused by different reasons in agro-industry units, in addition, methods of harvesting including green and burnt harvesting can cause qualitative and quantitative losses of canes. Thus, a split-plot in time design was executed, with the randomized complete block basic design in 5 replications, in Hakim Farabi agro-industry in 2015. The results showed that the interaction between time delay and harvesting method was significant in 5% level of probability in the main traits of sugarcane i.e. the amount of yellow and white sugar which is affected by other qualitative and quantitative factors. In such a way that the amount of yellow and white sugar during 5 days delay in burnt sugarcane was respectively 1.96 and 1.63 tons per each 100 tons, whereas the amount was 1.3 and 1.08 tons in green harvesting of sugarcane. Thus, compared to burnt sugarcane, green harvesting is less sensitive toward time delay. The invert, which represents loss of sugarcane quality, was separately significant in harvest and time treatments respectively in 1% and 5% levels of probability; in such a way that was 1.7 times higher in burnt sugarcane compared to green one day. The amount of invert in 5th day was 1.35 higher than 4th day.

Environmental concerns have become an important obsession around the world. Architecture plays an important role on the effects of human built environment to the globe. Passive solar energy helps to alleviate the Heating, Ventilation, and Air Conditioning (HVAC) costs and helps to lower the environmental effects. Central and east parts of Iran, called Central Plateau, have hot dry weather. Its traditional architecture propounded some solutions like using thermal inertia of materials to alleviate the severe weather condition of this area. Now, we have more developed industry and different innovations have enhanced buildings materials. In this research, it has been tried to propose a solution for gathering the benefits of traditional and today architecture n hot arid zone of Iran. The proposed system is based on motility of insulation for optimizing the use of thermal inertia and thermal insulation daily and annually. Using smart buildings saves lots of energies and lets the building to respond to its environmental changes like a living creature.

Activated carbon was prepared from Sterculia quadrifida seed shell waste by Phosphoric acid activation. The adsorption of Acid Blue 92 and Direct Red 28 on this Phosphoric acid treated activated carbon was investigated to assess the possible use of this adsorbent for the processing of dyeing industry wastewater. The influence of various factors such as initial dye concentration, temperature and Particle size on the adsorption capacity has been studied. Kinetic data have been studied using Pseudo-first order, Elovich model and Pseudo-second order equations for understanding the reaction mechanism.

Undoped and Mn doped lead sulfide (PbS) thin films were grown on glass substrate by Successive Ionic Layer Adsorption and Reaction deposition method. Mn content in aqueous solution was varied by adding 0.1, 0.25 and 0.5 mol of manganese chloride. The structural, surface morphological, optical properties and magnetic properties of the films were studied by X-ray diffraction, scanning electron microscopy, UV-Vis spectroscopy, Atomic force microscopy and Vibrating Sample Magnetometer respectively. The X – Ray diffraction studies reveal that the Mn doped PbS thin films were polycrystalline in nature with preferential orientation along (2 0 0) plane. The scanning electron microscopy results indicate that the films were uniform. The bandgap energy of PbS and Mn doped PbS thin films are 2.4 eV and 3.1 eV. The Atomic Force Microscope results indicate that the films are uniform and adherent to the substrate. The VSM studies reveal that the thin film exhibit multi domain behavior.