The effect of substituted benzene dicarboxylic acid linkers on the optical band gap energy and magnetic coupling in manganese trimer metal organic frameworks

We have systematically studied a series of eight metal-organic frameworks (MOFs) in which the secondary building unit is a manganese trimer cluster, and the linkers are differently substituted benzene dicarboxylic acids (BDC). The optical band gap energy of the compounds vary from 2.62 eV to 3.57 eV, and theoretical studies find that different functional groups result in new states in the conduction band, which lie in the gap and lower the optical band gap energy. The optical absorption between the filled Mn 3d states and the ligands is weak due to minimal overlap of the states, and the measured optical band gap energy is due to transitions on the BDC linker. The Mn atoms in the MOFs have local moments of 5 mu B, and selected MOFs are found to be antiferromagnetic, with weak coupling between the cluster units, and paramagnetic above 10 K

Restrained Shrinkage of Fly Ash Based Geopolymer Concrete and Analysis of Long Term Shrinkage Prediction Models

The research presented in this manuscript describes the procedure to quantify the restrained shrinkage of geopolymer concrete (GPC) using ring specimen. Massive concrete structures are susceptible to shrinkage and thermal cracking. This cracking can increase the concrete permeability and decrease the strength and design life. This test is comprised of evaluating geopolymer concrete of six different mix designs including different activator solution to fly ash ratio and subjected to both restrained and free shrinkage. Test results obtained from this experimental setup was plotted along with the available empirical equation to observe the shrinkage strain of GPC and a model was suggested to predict the shrinkage strain of GPC. It was found from this study that along with activator solution to fly ash ratio the final compressive strength of GPC plays an important role on shrinkage strai

Soret Effect on Transient MHD Convective Flow past a Semi-infinite Vertical Porous Plate with Heat Sink and Chemical Reaction

This problem concerns with an analytical study of heat and mass transfer on unsteady MHD convective flow past a semi-infinite porous vertical plate in presence of thermal diffusion, heat sink and chemical reaction. A uniform magnetic field is imposed transversely to the plate. The governing equations are solved by perturbation technique. The expressions for the velocity, temperature and concentration fields as well as transport properties are obtained in non-dimensional form. The influence of the physical parameters like magnetic field parameter, Schmidt number, Prandtl number, heat sink parameter, chemical reaction parameter and Soret number on these fields is discussed through graphs and tables. It is found that the presence of thermal diffusion enhances the fluid motion

The Potential Impact of Electronic Services to Rafah Municipality's Operational Excellence

This study investigates the potential impact of electronic services in achieving operational excellence, using the Rafah municipality as a case study. The ARIMA model was employed in the study to forecast changes in the municipal cost trend. Additionally, a questionnaire was designed, to collect data from the study population of 329 employees in the Rafah municipality, a descriptive-analytical technique using the least squares method was utilized to estimate the regression equation of the operational excellence components (time and cost). The results demonstrate that the anticipated costs will reduce, with a relative decline rate of 1% for the years 2023, 2024, and 2025. Furthermore, the statistical findings showed that a change in the level of software package measurement of one unit would result in a 0.50-degree improvement in the transaction time index and a 0.29-degree decrease in cost. According to the results cited, electronic services had a statistically significant impact on the municipality of Rafah's achievement of operational excellence. Therefore, this study recommends implementing digitization to achieve operational excellence and establishing a technology unit that would be entrusted with supervising all facets of managing and improving municipal systems. Keywords: Electronic services, Digital transformation, Software packages, Knowledge management, Website, Operational excellence. DOI: 10.7176/EJBM/15-17-10 Publication date:October 31st 202

Design and implementation of PSO/ABC tunned PID controller for Buck converters

In the recent years, Buck converters have been widely involved in a variety of the everyday applications such as smartphones and PCs. Buck converters can provide better and steadier performance when integrating a control system in the design. Therefore, it is interesting to work on this integration and gain the required efficiency in term of the gained voltage. In this paper, PID controller is adopted to control the output voltage of the Buck converter. An optimization is achieved on the performance of the Buck converter using two bio-inspired algorithms namely, Particle Swarm Optimization (PSO) and Artificial Bee Colony (ABC). The voltage controlled Buck converter system is simulated using MATLAB environment to validate the proposed PID controller system. In this study, the voltage regulation process of Buck converter is investigated based on many working disturbances such as the change in the supply voltage, reference voltage, and load resistance in order to verify the robustness of the proposed PID controller. Finally, the feedabck voltage control system of the Buck converter is implemented experimentaly in real-time to validatde the simulated PID controller

Can Palestine Banks Develop Credit Risk Management According to Basel III?

In this paper, we investigated Palestine bank sector ability to develop credit risk management systems based on international standards (Basel Capital Accord). First, we evaluate the credit risk management systems and strategies that the operating bank in Palestinian banking system mandate. Second, we used the analytical description methodology to describe the new Basel accord for effective banking supervision. Our study showed that despite the banks prefer to use the Standardized Approach in measuring credit risk according to Basel committee approaches, it is still difficult for Palestinian banks to measure credit risks according to Basel III approaches. Keywords: Basel III approach, capital adequacy, Risk management, Palestine Monetary Authorities (PMA

Basel III, And Banking Risk; Do Basel III Factors Could Predict the Risk of Middle-Eastern Countries?

The research is financed by the Nation Natural Science Foundation of China under number 71173060. Abstract The global financial crisis in 2008 shows that the successive agreements Basel I, and II failed to stop the global financial collapse. Therefore, this research tries to answer the study question that; can Basel III enhancement give the banking sectors stability? Our data includes 324 listed from the largest banks across Middle East. Results from PLS-SEM analyses demonstrate bank risk is positive relationship related to charter value, information systems and Internal/External control systems. We find negative relationship among bank risk and market discipline. Following our finding, the result shows there is no relationship between bank risk and bank capital and the results suggest that Charter Value is the most important predictor of bank risk. Keywords: Basel III, Bank Risk, Bank capital, charter value, information system, control system, market discipline, Middle East

The Impact of Cracked Microparticles on the Mechanical and the Fracture Behavior of Particulate Composite

In this investigation a metallic composite with a cracked micro has been investigated using finite element method. Particulate reinforced composite is one of the most favorite composite due to it quit isotopic properties. While being in metallic status, the micro particles may be subjected to deterioration which lead to crack embedded initiation within the micro particle. This crack lead to degradation in the mechanical as well as the fracture behavior in the composite. Mechanical characteristics through estimating the stiffness of the composite has been studied for intact and cracked particles as well as for the fractured particles. It has been found that as long as the crack propagates in the micro particle, there is reduction in the composite stiffness and increases in the stress intensity factor (SIF)

A New Log Lindley Distribution with Applications

This paper introduces a new generalization of the Lindley distribution introduced by [1], using the basic idea of [2] and along the lines of [3]. The new distribution is a compound of the Lindley and logarithmic distributions. We refer to the new model as the logarithmic-Lindley (Log-L) distribution. This model is capable of modeling various shapes of aging and failure criteria. The properties of the Log-L model are discussed, and the maximum likelihood estimation method is used to evaluate the parameters involved. Finally, the usefulness of the new model for modeling reliability data is illustrated using a two real data sets with simulation study

Effect of GEMPEHD thermal properties on the propagation of heat in solar stills

The properties of GEMPEHD as an absorber material in a prototype of solar still have been investigated in a temperature range from 300 K to 400 K. Results showed a dependency between temperature and its properties. The enegy absorbed by the GEMPEHD increases its temperature, the power received by the air and the air temperature. Overall losses increase with the difference of the temperature between the GEMPEHD and windows. This increases the efficiency of the solar still and minimizes the entropy of the system. The study of thermal aging is dedicated to the interpretation of various analyses the GEMPEHD before and after its use in the solar still. The thermal aging GEMPEHD in the air is a physical loss and chemical consumption immediately followed by a brutal oxidation of the polymer. The losses would be governed primarily by the chemical consumption of antioxidants.Keywords: GEMPEHD, temperature, solar collector, agin