Archives-  

In recent years, preparation of polymer materials either soluble or insoluble in water with various functional groups has been developed, which can absorb metal ions in aqueous and non-aqueous media. In general, functionalized polymers for metal ion complexation can be prepared either by derivation of a basic polymer (precursor) with the desired ligand or by polymerization of the corresponding ligand derivatives. Among functionalized polymers, those containing EDTA have attracted much attention. EDTA with amino carboxylic acid groups can be introduced into or graft onto the backbone of polymer chains. Polymers bearing such groups can form stable complexes with various heavy metal ions. Therefore, we attempted to prepare new complexing polymer materials, which can be used in wastewater treatment. The synthesised random copolyesters were characterized by viscosity measurements, solubility studies, and spectral analysis. Thermal studies were also made on these copolyesters.

4-aminopyridinium oxalate (4APO), an organic nonlinear optical single crystal has been grown by slow evaporation solution growth technique. Single crystal X-ray diffraction studies were carried out to determine the unit cell parameters.4APO crystallizes in monoclinic system. The grown crystal has been characterized by Fourier transform infrared and UV-Visible spectral studies. Thermogravimetric analyses (TGA) and differential thermal analysis (DTA) have been carried out to study the thermal behavior of the grown crystal. The mechanical stability of the grown crystal has been studied by using Vickers microhardness test. The Kurtz and Perry powder SHG technique confirms the NLO property of the grown crystal.

Benzotriazole has been prepared as a corrosion inhibitor to control the rate of corrosion. This compound has been investigated as corrosion inhibitor at room temperature for preventing mild steel corrosion in Sulphuric acid medium at different concentration at two hour time interval by weight loss method. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with Sulphuric acid concentration. Also, it was found that the corrosion inhibition behavior of Benzotriazole is greater in 1M H2SO4 when compared to 2M H2SO4 at two hour time interval. So Benzotriazole can be used has a good inhibitor for preventing mild steel material for many construction purpose.

In the world wide network, there are several websites, in which each and every system has to be protected securely. The DNS Security Extensions (DNSSEC) make DNS the first core Internet system to be protected using public key cryptography. The DNSSEC not only protects the DNS, but has created interest in using this secured global database .There are several websites which are protected using different security schemes and are made less prone to the intruder .To save the data from misused, the admin control are also needs to be protected from viewing the public data. And to enforce these techniques, we need to fully encrypt the data and the database from viewing the actual data and transform into unusual data .Therefore, the data has been hided and protected from general view. In this paper, I propose to achieve a new theoretical model, called Public Data, which is robust and free from verification deployments as Communities of Trust (CoTs) by which it makes them secure . A reasonable DNSSEC deployment model and a typical choice of a CoT, has been properly implemented to protect the full data access for the general view of the user. Our limited deployment of Vantages has outperformed the verifiability of DNSSEC and has properly validated .Then the various adversary would be able to Man-in-middle attacks on arbitrary traffic into autonomous systems. Then the whole database and the backend process are encrypted and are in non-viewable formats.

Present paper addresses to the most important implications of natural rights including the right of life, freedom, equity and ownership that are based on many other rights. The answer to this question that whether rights in today constituting are influenced by natural rights is positive and its importance is emphasized in interpreting constitutions. It is also tried to determine it and to clarify the way of entering natural right concepts to constitutions. Hence, in the first discourse, it is shown that in terms of natural right school practitioners, the right of life, freedom, equity and ownership are natural rights. In the second discourse, the channels of entering natural rights to constitutions are studied including entrance through declarations especially human right global declaration and constitutionalism. The amount and way of natural right implications for Iranian Constitution is also considered.

The main focus of this study was to probe the relationship among motivation, high school classroom stress, and academic achievement of Iranian high school learners. Students’ motivation was surveyed and analyzed using Instrumental Motivation designed by Kimura et al. (2001) and their classroom stress was measured through the Vulnerability to Stress designed by Miller L. and Smith A. D. (1985). Furthermore, in order to get the participants’ academic achievement, their Grade Point Average (GPA) will be taken into account as well as the grade of English course. The results of the Spearman rank order correlation coefficient indicate that there is moderately negative relationship between classroom stress and instrumental motivation. Regarding the relationship between instrumental motivation and academic achievement, motivation was only slightly related to scores on English course. Findings also demonstrated that classroom stress was negatively related to learning English.

This study summarizes the steps for forecasting Natural gas consumption in Bangladesh’s power sector using Box-Jenkins autoregressive integrated moving average (ARIMA) time series model. For this study a structure for ARIMA forecasting model is being proposed where a time series is expressed in terms of past values of itself plus current and lagged values of a ‘white noise’ error term. Validity of the model was tested using standard statistical techniques and the best model is proposed on the basis of various diagnostic and selection & evaluation criteria. The findings of the study will provide policy makers in Bangladesh a long term perspective of natural gas consumption in power sector along with necessity of exploring other alternative energy sources and assist in adopting proper strategies to address the power supply situation of Bangladesh.

Ultrasonic velocity, absorption and EPR measurements are carried out with manganous sulphate (MnSO₄) & vanadyl sulphate (VOSO₄) salts in water-glycerine mixtures in the concentration range 0.1-0.6 (w/w). The results are discussed on the basis of Hall’s two state model and molecular interaction due to complex formation between water-glycerine and water-paramagnetic ions. The spin Hamiltonian parameters for MnSO₄ & VOSO₄ from EPR spectra have been evaluated.

The development of new technology increases the exposure level to non-ionizing EMF radiations. Recent development of spatial data management in the framework of GIS has created a new trend of environmental mapping. In this work, maps for different EMF sources have been developed for the Baghdad city using Arc Map GIS version 10, the utilization of such spatial analysis maps is very important for future planning and EMF exposure assessment studies. Statistical analysis for measurement data was made using IBM SPSS Version 20. The maximum contribution of EMF exposure was referred to FM radio stations and GSM mobile base station due to high power transmitters and large number of base stations, maximum EMF strength caused by FM radio stations was 10.2 (V/m) and the average exposure level 3.578 (V/m). High-level exposure values unveil the necessity of imposing new recommendations and limits concerning stations site selection and reducing exposure levels in residential areas as low as possible.

Visual Data mining (VDM) is extensively used and being studied field of research area now a days. We surveyed in this paper the basic idea behind the visual data mining. How and why we have to classify the VDM techniques and corresponding classification criteria’s. We also presented some of its advantages.