ester and N-[4-(2-amino-3-hydroxy-pyridin-6-ylazo)phenyl]-acetamide compounds were studied. The dissociation constants were determined potentiometrically. The thermodynamic parameters of dissociation were evaluated. Regression analysis is applied for correlating the different parameters. The results help to assign the solute-solvent interactions and the solvatochromic potential of the investigated compounds. The electronic character of the substituent and the chemical nature of the solvent are major factors for the observed solvatochromism. Nitroso Pyridin-6-ylazo Triazene Effect of solvents Potentiometry Spectrophotometry

The satellite structural mass is considered a crucial parameter during the process of satellite structural design. Sandwich structures acquire a considerable role in minimizing such mass while maintaining structural integrity. This article discusses the structural configuration, design, and analysis of a small satellite. A small Earth remote sensing satellite is chosen from the published data as a case study. Its structural design configuration is of a rectangular box that is based upon metallic alloys. Through a comprehensive study, the most suitable design configuration for the given mission is selected. A contribution has been made in developing a novel hexagonal primary structure that is based upon Aluminum honeycomb sandwich panels. The satellite configuration process and structural design procedure are thoroughly presented. The finite element modeling of honeycomb sandwich panels according to sandwich theory is introduced. Such modeling is validated numerically in comparison with published data. The analysis process is implemented using finite element analysis considering the loads during the ground and launch phases. The proposed structural design results in a significant mass reduction of 15% when compared with the baseline case study.

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Urban climatology is a complex field owed to the intersecting parameters. In city planning, neighborhood fabric and vegetation plays a great role in modifying arid microclimates. This work presents an approach to enable urban designers to find the optimum land use parameters to achieve pedestrian thermal comfort. In this study, a model was developed based on ENVI-met simulations of two urban and suburban sites in Cairo, Egypt. Initial design parameters were; compactness degree, grass coverage, leaf area density, trees ground coverage, and asphalt and buildings areas. After regression analysis, the step-wise algorithm succeeded in creating the best fit of 94% R2 and 92% adjusted R2. The suggested Urban Design Comfort Model (UDCM) was examined using MATLAB to find the optimum design parameters. Optimum values were applied to generate primitive urban configurations using Grasshopper. The primitives were simulated again in ENVI-met to validate UDCM. The resulted value of Physiological Equivalent Temperature, PET at peak time was reduced from the initial result of ENVI-met (42.3 °C) in both sites to reach (38.7 °C) then (36.8 °C) after refinement with extra foliage. This approach, as a tool for urban designers, not only facilitates and speeds up urban form design process on a passive basis, but also provides deep insights on the development of UDCM considering all different city transects rather than two.

This review paper covers the subject of vehicle design for protection against the blast of improvised explosive devices. It summarizes the most recent techniques in the design of vehicle structures for blast protection. This review pinpoints the challenges in designing a vehicle for blast protection and maintaining acceptable mobility at the same time. In addition, this paper reveals and summarizes key design principles based on the critical assessment of the published literature. This review covers the state of the art design methods for each individual part of vehicle structure. It also identifies the role of human protective gear and its effectiveness in mitigating blast related injuries. This review suggests future trends in developing innovative protective structures that are inspired by nature or manufactured. The aim of this review is to guide and advance the research of vehicle design for blast protection.

This work was carried out to study the quality of water of Rosetta branch. Five sites were chosen for sampling during the period of January 2013 to December 2013. Physical parameters (Temperature, electrical conductivity (EC), turbidity and pH) and chemical parameters (concentration of Cl-, Ca+2, Mg+2, NH4+, SO4-2, NO2-, and some of trace metals, alkalinity, total hardness, Dissolved Oxygen(DO), Chemical Oxygen Demand(COD) and Biological Oxygen Demand(BOD) were discussed. These results were compared with the results of another study that were carried out at Rosita Branch at 2018. Statistical analysis of data was computed to show the correlation between some parameters through the whole sampling sites during the period of the study, using simple correlation coefficient.

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Nonlinear finite element simulation is the state of the art tool to assess the crashworthiness performance of current automobile design. Despite all the advancements in today's computational capabilities, simulations are still extremely computationally expensive. Moreover design optimization for crashworthiness is a highly nonlinear mathematical problem in which both analysis and optimization components are nonlinear and involve highly iterative process. This makes design optimization process prohibitively possible due to the associated unrealistic computational cost. This paper presents a practical approach that enables the designer to conduct design optimization for crashworthiness at an affordable computational cost.