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PVP-Assisted Synthesis of Fe/Ceo2 Nano-Alloys Prepared by Solgel Method
No full textFe/CeO2 nanoparticles (NPs) were synthesized by simple co-precipitation method Iron chloride hexahydrate (FeCl3.6H2O) and cerium chloride (CeCl2·5H2O) as precursor in the presence of polyvinylpyrrolidone (PVP) surfactant and ethylene glycol agent. The samples were characterized by high resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and electron dispersive spectroscopy (EDS) in different temperature. The XRD results showed that Fe-doped CeO2 was single-phased with a cubic structure. The particle size of as-prepared sample was in the range size of 15-45 nm and annealed sample was around 22 nm in diameter at 800oC for 3 hours. The TEM studies showed the 17 nm squared-like shaped nanosized particles. EDS shows peaks of iron and cerium with less impurity in prepared samples and Fe/Ce ratio was also decreased with increasing annealing temperature
Anisotropy and Isotropy Degrees of Mgo And Mgsio_4 At Different Temperatures
No full textThe norm of elastic constant tensor and the norms of the irreducible parts of the elastic constants of and at different temperatures at different temperatures along with the experimental data obtained under adiabatic condition. The relation of the scalar parts norms and the other parts norms and the anisotropy of these materials is presented. The norm ratios are used as a criterion to present the anisotropy degree of the properties of these. 
Realization of Equilibrium Distributions of Molecules in Gases Boris Georgievich Golovkin
Get PDFIt is shown that all possible distributions of molecules of an ideal gas with zero dimensions of monatomic molecules that collide elastically with each other are in equilibrium, and with nonzero dimensions, a universal equilibrium distribution of the gas molecules along with the velocities and angular momentum must arise. In a real gas in an isolated system, due to dissipation, evolution goes simultaneously toward the universal distribution and toward the occurrence of an equal-velocity distribution, and also towards the degradation of the gas due to the decrease of the molecular velocities to zero values. In a non-isolated system, the real gas has a distribution close to the Maxwell distributio
Theory of Square Wave Voltammetry of Two Reversible Electrode Reactions Connected by The Reversible Chemical Reaction
Get PDFA theory of the mechanism that consists of two reversible electrode reactions coupled by kinetically controlled reversible chemical reaction is developed for square wave voltammetry on stationary planar electrode. The influences of frequency and the concentration of electro-inactive chemical reactant on the responses are investigated for thermodynamically stable intermediate. The limits of three types of responses are calculated and the formula for the estimation of the forward rate constant of chemical reaction is proposed
Silver containing calcium phosphate bone cement with Ag/Ca atomic ratio equal to 0.05: synthesis and characterization
Get PDFThe introduction of silver into calcium phosphate bone cement (CPC) increases the strength and antimicrobial activity of the material. In this study, we synthesized silver-containing CPC by introducing silver phosphate salt Ag3PO4 in the cement powder with an Ag/Ca atomic ratio equal to 0.05. α-Tricalcium calcium phosphate (α-TCP, Ca3(PO4)2) and Hydroxyapatite (HA) were mixed with dicalcium phosphate dihydrate (DCPD, CaHPO4.2H2O) to form the cement powder. Deionized water (DI) solution was used as the cement fluid. CPC based on silver containing apatite phase was obtained. The phase composition and setting time of the cement was determined. The formation of apatite was verified by XRD and FTIR analysis, the initial and final setting times of the cement are 11 and 35 min
Development and Characterization of Sodium Alginate Beads for Metformin
Get PDFThe metformin is anti diabetic drug. In this study the sodium alginate beads were prepared with different oils preparing emulsion first. The drug is entrapped and measured for its drug content and swelling index. The beads were prepared and evaluated on different parameters. 
High Performance Liquid Chromatography-Size Exclusion Chromatography (Hplc-Sec) As an Efficient Tool for The Quantification of Polymers
Get PDFPoly (lactide-co-glycolide acid) ( PLGA) is an extraordinary well-described polymer and has excellent pharmaceutical properties like high biocompatibility and good biodegradability. Hence, it is one of the most used materials for drug delivery and biomedical systems, also being present in several US Food and Drug Administration approved carrier systems and therapeutic devices. For both applications, the quantification of polymer is important. During the development of the production process, parameters like yield or loading efficacy are essential to be determined. Although PLGA is a well-defined biomaterial, it still lacks a sensitive and convenient quantification approach for PLGA-based systems. Thus, we present a new method for fast and precise quantification of PLGA by HPLC-SEC. The method includes a shorter run time of 20 minutes with a size exclusion column of 300mm x 8.0mm diameter, tetrahydrofuran as mobile phase and diluent, the detection was carried out using the refractive index detector. The developed method has a detection limit of 0.1 ppm, enabling the quantification of low amounts of PLGA. Compared to existing approaches, like gravimetric or nuclear magnetic resonance measurements, which are tedious or expensive, the developed method is fast, ideal for routine screening and it is selective since no interference. The developed method is validated in terms of selectivity, precision, linearity, accuracy and solution stability. Due to the high sensitivity and rapidity of the method, it is suitable for both, laboratory and industrial use  
A Descriptive Correlational Investigation into Factors That Impact on Job Satisfaction Among 40 Conveniently Selected Participants in an Urban Setting
Get PDFJob satisfaction relates to an individual’s level of contentment within an assigned organization and is influenced by the individual’s likelihood of promotion, perceptions of the stability of the work environment and many other demographic relationships. North America and the United Kingdom have produced evidence supporting this position for the last five decades. Accordingly, this study employed a descriptive correlational design to examine the factors that influence job satisfaction. A convenient sample of 40 respondents from varying urban companies were recruited to participate in the study. The data were analyzed using SPSS version 21 software. Non-Parametric Statistical tools such as Bivariate Correlations and One-way ANOVA tests were used to examine the relationship between demographic factors and job satisfaction as well as employee support systems and jobs satisfaction. A conceptual framework was developed based on the variables under examination. The results indicated that supervision, business format and advancement on the job criteria had strong positive relationships with employees’ level of job satisfaction. Authors concluded that employee support systems need to be enhanced to reduce attrition and to promote, strengthen and develop burgeoning and established companies
Economic Independency of Women and Separation Rate in Muslim Marriages in Bangladesh
Get PDFWomen’s participation in the workplace and their economic independence in Bangladesh have been increasing since its independence. The key objective of this research is to show the relations between women’s economic independence and separation in Muslim marriage in Bangladesh. This paper argues that although there is an increase in women's economic independence, because of conflicts in traditional and modern values and the existence of children in families, the separation rate has increased more than the divorce rate in Bangladesh. In order to explain this argument, this research employs both qualitative and descriptive methods of data collection and analysis to measure the relationship between women’s economic independence and separation rate. Finally, this research suggests that it is necessary to create a balance between existing social structure, economic reality, and individual's needs to strengthen and enrich marital life. Otherwise, it can be said that the rate of separation and divorce in Bangladesh will be continuously increasing that will help to make a new family structure in the country
Boko Haram Insurgency and The Underdevelopment of Girl- Child in Nigeria: Implication for National Development
Get PDFIn recent times, however, millions of girl child in Northeastern schools in Nigeria are caught up in conflicts that result in insecurity which affect their school attendance and their lives. This paper examines the effect of Boko Haram Insurgency on girl- child attendance in secondary schools in North-Eastern Nigeria. The study purposively selects three states in northeastern Nigeria. The study employed primary and secondary data; 360 respondents were randomly selected. The Ordinary Least Square (OLS) regression model was used to analyses data collected. The OLS regression model result shows that the R2 is as high as 0.680, this suggests that Boko Haram has an influence on the girl- child attendance in secondary schools Northeastern Nigeria, therefore, the null hypothesis that Boko Haram insurgency has no significant effect on Girl- child attendance in Secondary Schools in Nigeria is rejected. This implies that the Boko Haram insurgency has significant effect on Girl- child attendance in Secondary Schools in Nigeria. The study recommended that professional public-private partnership (4 P’s) should provide all necessary support to teachers and students, who have been affected by violence in northeast Nigeria, this should include rehabilitation and resettlement for those who have been forced to flee to return for academic pursuit