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Abstract This article presents a Z source (ZS) based switched capacitor multilevel inverter (SC-MLI) with low capacitors charging inrush currents utilizing a modified modulation strategy. The topology generates nine output voltage levels with quadruple voltage gain utilizing eight power switches, five capacitors, two inductors, four discrete diodes, and a single DC source. The voltage gain can be further increased by applying shoot through (ST) states to the frontend ZS-network. Owing to its high voltage gain, the topology is suitable for low voltage renewable energy sources such as photovoltaics (PV), and fuel cells (FC). A modified modulation strategy is presented based on the conventional level shifted sinusoidal pulse width modulation (LS-SPWM). The proposed modulation strategy improves the dc-link utilization at higher modulation index. A detailed mathematical analysis is provided for the gain calculation based on the modified modulation strategy. A comparative study is implemented to verify the merits of the proposed topology. A simulation model is implemented utilizing MATLAB / Simulink to verify the topology characteristics. The power losses and efficiency calculations are presented using Altair PSIM. Furthermore, an experimental prototype is constructed to verify the simulation findings. The topology is tested with different loading conditions at numerous modulation index values and ST duty ratios. Furthermore, step change conditions are implemented to test the topology response. The effect of the ZS network on the switched capacitors charging inrush currents is validated. The proposed topology shows an overall advantage in terms of the output characteristics as well as the hardware requirements.

Abstract In this paper, a single stage buck–boost DC–AC converter based on coupled inductors is presented for renewable energy and electric vehicle applications. The proposed topology works with only three semiconductor switches, two diodes, and three coupled inductors to transfer input DC voltage to a high gain or low gain output AC voltage. A coupled inductor is used instead of normal inductors, which will reduce core and size requirements. The sinusoidal pulse width modulation strategy is used in this paper for controlling the main switch. There are many merits in the presented topology, like high gain up to five times of input voltage, compact size, less number of components, which results in reducing the overall cost, reducing switching loss, and increasing the converter efficiency. The simulation study is carried out using MATLAB/SIMULINK to simulate the operation of the proposed converter. Also, an experimental setup is built up to examine the actual operation of the proposed converter. There is a good agreement between simulation and experimental results which increases the validation and confidence of the model.

Today, the biggest challenge faced by the refining industries globally is the production of environmentally friendly fuels with a high amount produced annually to meet the needs of markets due to the sharp regulations imposed environmentally with allowable sulfur levels in diesel fuel. This study examines the most recent developments in solid sorbent adsorption and catalytic oxidization techniques for desulfurizing diesel fuel. Reviewing the benefits, limitations, and future potential of each technique for desulfurizing liquid fuels using solid catalysts constructed using waste from agriculture. Activated carbon is one of these carbon materials; however, the traditional methods of producing activated carbon are time-consuming and costly. Activated carbon has impressive characteristics such as low concentration of ash, enormous surface area, permeability, ease of being activated, and high compressive strength, thereby rendering this an ideal substrate for the synthetic production of heterogeneous catalysts. Because they are in charge of igniting the substances that oxidize, their supported catalysts are crucial to the oxidation process. Various types of homogeneous and heterogeneous catalysts such as metal oxides, ionic liquids, polyoxometalates, and organic acids have been used to form oxidative desulfurization (ODS) systems. Therefore, to enhance the efficiency of catalytic ODS process some modifications must be taken into account. These adjustments may involve doping the catalyst’s surfaces with metal oxides or increasing the catalyst’s surface area when combined with sulfur compounds. In addition to reviewing the preparation conditions for carbon waste-based activated carbon catalysts, this work also carried out the desulfurization procedures to remove substances containing sulfur. Overall, the comprehensive review of carbon wastes into activated carbon catalysts with conventional and microwave heating shows promises in addressing two pressing environmental issues: agriculture waste management and reducing the ODS cost through the production of a sustainable fuel-efficient catalyst. This review explores the environmental feasibility of agro-waste as a waste-to-energy (solid carbon) technology. The use of agro-waste as a source to produce activated carbon catalysts mitigates the environmental impact associated with traditional waste disposal avenues, such as incineration and landfilling.

One of the main sources of crude oil and product losses in refineries is the storage tanks. The lightest hydrocarbons in these tanks evaporate during operation, causing not only a loss of the precious raw hydrocarbon material but also a source of dangerous gas pollution. For calculating these losses, several direct and indirect approaches have been devised. In this study, we used a method based on the comparison of the differences in the characteristics of crude oil or other products. This work aimed to find the specifications of two products, kerosene and gas oil, and calculate the losses that occur for the quantities in the dispatch warehouse in the NRC. Four samples of kerosene were used and named: kero@02-1, kero@05-2, kero@10-3, and kero@11-4, while four samples of gas oil were named: gaso@02-1, gaso@05-2, gaso@10-3, and gaso@11-4. Also, they depend on the date of certificate issue, respectively. The received quantities were calculated in ml and converted to cubic meters using the tank coefficient (kerosene tank coefficient 0.638 and gas oil tank coefficient 0.408). Calculations were made of 1500 ml for kerosene and 2500 ml for gas oil. In addition, this project dealt with a simplified method of work that includes the physical properties to find the actual quantities that are lost for the mentioned petroleum products. Moreover, the highest losses were for kerosene (5 m 3 ) at sp. gr 0.750, and the highest losses were for gas oil (5 m 3 ) at sp. gr 0.820. The results showed that there is a quantity of fluctuating losses that does not exceed 5 m 3 / 1000 m 3 and that these losses are in accordance with the permissible limits. The results recommend directing the laboratory tester's teams in the NRC Baiji to conduct periodic examinations of the petroleum products, as well as not to collusion when receiving a low product with laboratory examination specifications to reduce losses in quantities.

Abstract In this paper, a single-phase direct pulse width modulation (PWM) buck-boost AC–AC converter is proposed. The proposed converter utilizes a minimum number of semiconductor switches and passive components that decreases the converter power losses and offers high efficiency. It can be operated with simple PWM control and doesn’t require soft-commutation strategies. It does not suffer from input source shoot-through and commutation problems. Moreover, it supplies both continuous input and output currents. The common sharing ground of the input and output gives the proposed converter the feature that it can be utilized for voltage sag and swell compensation. A comparison of the proposed converter performance with similar existing converters is presented. Also, detailed circuit analysis, component design guidelines, and simulation results using the MATLAB/Simulink environment are demonstrated. A laboratory prototype has been built and tested to validate the converter performance and confirm the results obtained by computer simulation.

Innovative, low-loss, and compact optical systems are essential to meet the experimental requirements of emerging novel radiation sources. The microchannel plate (MCP), a metamaterial-based optical device, shows promising potential for shaping, condensing, and focusing soft x-ray radiation at synchrotron radiation (SR) facilities. This study highlights the impact of MCP optical devices on SR beam condensing capability and their sensitivity to the degree of coherence by investigating the profile of transmitted beams through single and double MCP optical devices. Transmitted diffraction patterns of soft x-ray SR radiation change with energy and radiation modes. At 92 eV, the double MCP-based device affects the beam divergence and degree of coherence more than the single MCP. Moreover, the double MCP device shows potential as a condensing optics at shorter wavelengths, i.e., 480 eV. Experiments were performed at the available end-station of the Circular Polarization beamline at the Elettra synchrotron facility in Trieste, using a high-vacuum chamber with a hexapod system, providing the precise movement necessary to align these diffractive optics. The findings contribute to the development of innovative optical systems for SR and free-electron laser beamlines, paving the way for advanced experiments in spectroscopy, microscopy, and imaging in a wide energy range. [ABSTRACT FROM AUTHOR]

Copyright of European Poultry Science / Archiv für Geflügelkunde is the property of Verlag Eugen Ulmer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Machine learning algorithms have gained popularity recently as a method for predicting the efficiency of industrial processes. The fluctuation of desulfurization process operation conditions, especially sulfur content in diesel fuel, has an impact on the efficiency of the process. This study presents the development of an artificial neural network (ANN) model using Python to predict the efficiency of the oxidative desulfurization (ODS) process in highly sour diesel fuel. Experimental data from a trickle bed reactor were used to train and validate the model. The dataset included variables such as ODS temperature, pressure, liquid hourly space velocity (LHSV), and sulfur content in the feed. The ANN model demonstrated a high prediction accuracy with sulfur conversion results matching the experimental data with approximately 98% accuracy and a regression coefficient (R²) of 0.99. The model effectively captured the influence of the operating conditions, showing that higher temperatures and pressures significantly enhanced the desulfurization efficiency. Additionally, the optimization of LHSV contributed to achieving optimal sulfur removal. This work highlights the potential of machine learning techniques in enhancing the predictive capabilities and efficiency of industrial desulfurization processes. [ABSTRACT FROM AUTHOR]

Genes encoding KIRs vary in frequency among different populations and ethnic groups. This study investigated the KIR gene frequency distribution in 148 healthy unrelated Saudi subjects and compared the results with other published findings. All inhibitory and activating KIR genes were present at variable frequencies, with A haplotype-associated genes (KIR2DL1, -2DL3, -3DL1, and KIR2DS4) being observed at higher frequencies (88.9-99.5%) than B haplotype-associated genes (KIR2DS1, -2DS2, -2DS3, -2DS5, -2DL5 and -2DL2) (31.1-70.1%). Thirty-one different KIR genotypes were observed, and AA genotypes displayed the highest frequency (18.2%). This Saudi population possesses similar KIR gene distributional characteristics to those reported in other neighboring populations (e.g., Lebanese) and shows disparities in certain genes and gene contents from other populations (e.g., Australian Aborigines). These findings can be used as a reference control in future studies evaluating the functional significance of the KIR genes and their associations with specific diseases.

Copyright of Journal of Petroleum Research & Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the main sources of crude oil and product losses in refineries is the storage tanks. The lightest hydrocarbons in these tanks evaporate during operation, causing not only a loss of the precious raw hydrocarbon material but also a source of dangerous gas pollution. For calculating these losses, several direct and indirect approaches have been devised. In this study, we used a method based on the comparison of the differences in the characteristics of crude oil or other products. This work aimed to find the specifications of two products, kerosene and gas oil, and calculate the losses that occur for the quantities in the dispatch warehouse in the NRC. Four samples of kerosene were used and named: kero@02-1, kero@05-2, kero@10-3, and kero@11-4, while four samples of gas oil were named: gaso@02-1, gaso@05-2, gaso@10-3, and gaso@11-4. Also, they depend on the date of certificate issue, respectively. The received quantities were calculated in ml and converted to cubic meters using the tank coefficient (kerosene tank coefficient 0.638 and gas oil tank coefficient 0.408). Calculations were made of 1500 ml for kerosene and 2500 ml for gas oil. In addition, this project dealt with a simplified method of work that includes the physical properties to find the actual quantities that are lost for the mentioned petroleum products. Moreover, the highest losses were for kerosene (5 m3) at sp. gr 0.750, and the highest losses were for gas oil (5 m3) at sp. gr 0.820. The results showed that there is a quantity of fluctuating losses that does not exceed 5 m3 / 1000 m3 and that these losses are in accordance with the permissible limits. The results recommend directing the laboratory tester's teams in the NRC Baiji to conduct periodic examinations of the petroleum products, as well as not to collusion when receiving a low product with laboratory examination specifications to reduce losses in quantities. [ABSTRACT FROM AUTHOR]