Studying binary clathrate hydrate of hydrogen and deuterium using raman spectroscopy

In the scene of the increasing global need to find a good manner to use hydrogen as a source of energy; this research stand as one of the promising methods to do so. Clathrate hydrates show a possible material to store hydrogen which is a clean fuel and exist in nature in large quantities at different places. Clathrate hydrates are crystalline molecules with shape like ice, but have different crystal structure. Simply, applying high pressure and low temperature on water molecules will form Clathrate hydrate which represents a phase transition from water. About 6.4 trillion tones of methane-hydrates are found to be deep on ocean floor, which represent a significant source of energy just requires an efficient and economic method to be used. Besides the importance of clathrates in terms of energy demands, this research participates in increasing the knowledge of fundamental physical and chemical processes in one of the important international research topics. Raman spectroscopy has been performed on different samples of binary Clathrate hydrate of hydrogen and deuterium. Actually, we used Raman Spectroscopy because it is a powerful tool for investigating the molecular dynamics of the guest molecule inside the clathrate cages, in addition to estimating the occupancy number of molecules per cage. The experimental part of this thesis was done at CNR, Florence, Italy, while the data analysis was carried out at Physics department, The American University in Cairo in the scene of scientific collaboration between the two institutions

Production of Sustainable Aviation Fuel through Biomass:Experimental and Simulation approach

In this thesis, special attention is given to the influence of biomass characteristics and their uncertainties on the production of sustainable aviation fuel (SAF). As SAF mandates are being introduced to reach net-zero carbon emissions in the aviation sector, reliance on biomass feedstocks is growing; however, it comes with challenges and obstacles. Many pathways and configurations are being developed and scaled up to reach their full commercial potential. Resolving the challenges associated with biomass characterization will pave the way to the successful use of biomass in SAF production. Therefore, this thesis has two phases: an experimental and a simulation phase.Firstly, the experimental phase aims to improve the measurements of the biomass characteristics in the laboratory by performing a key comparison of the measurement techniques between different metrological institutes in the EU. The overarching goal of this phase was to lower the measurement uncertainty by improving repeatability and reproducibility. Eventually, new modifications to the ISO standards will be proposed. The improvement in the measurement accuracy directly impacts the values of purchasing and taxing biomass, as aspects like the energy and moisture content play a significant role in setting these values. Moreover, these improvements are expected to enhance biorefinery processes' design, performance, and yield.The second phase focuses on the impact of different types of biomass, their heterogeneity, and uncertainty on the production of SAF. Therefore, the various pathways of SAF production were comprehensively analyzed while considering technical and non-technical aspects to determine the most promising routes for producing SAF from biomass. Moreover, the analysis assessed the EU's biomass potential for SAF, focusing on its ability to meet proposed EU mandates for SAF uptake in the short and long term. After this analysis, several steady-state models for the Fischer Tropsch and Methanol to Jet were simulated in Aspen Plus commercial software. These models aimed to determine the influence of the experimentally determined biomass characteristics and their uncertainties on SAF production. Moreover, the models were used to determine the optimal and cost-effective pathway for SAF production through biomass. Different approaches, configurations, and tools were employed to achieve this objective, such as process simulation, sensitivity analysis, Monte Carlo simulation, and techno-economic analysis

An Improved Oscillation Result for a Class of Higher Order Non-canonical Delay Differential Equations.

[EN]In this work, by obtaining a new condition that excludes a class of positive solutions of a type of higher order delay differential equations, we were able to construct an oscillation criterion that simplifies, improves and complements the previous results in the literature. The adopted approach extends those commonly used in the study of second-order equations. The simplification lies in obtaining an oscillation criterion with two conditions, unlike the previous results, which required at least three conditions. In addition, we illustrate the improvement with the new criterion, applying it to some examples and comparing the results obtained with previous results in the literature

Sufficient conditions for oscillation of fourth-order neutral differential equations with distributed deviating arguments

Some new sufficient conditions are established for the oscillation of fourth-order neutral differential equations with continuously distributed delay. An example is provided to show the importance of these resul

A ‘GREEN’ STRATEGY FOR TRIPLE BOTTOM LINE CORPORATE SUSTAINABILITY: A CASE STUDY OF A MAJOR MANUFACTURER IN THE UAE

ABSTRACT A ‘GREEN’ STRATEGY FOR TRIPLE BOTTOM LINE CORPORATE SUSTAINABILITY: A CASE STUDY OF A MAJOR MANUFACTURER IN THE UAE By Abdelmoniem Saeed This thesis research study is of a major manufacturing corporate located in UAE that has been suffering from a business dilemma represented by a dramatic financial decline and a significant deterioration in social and environmental business-related elements. The fundamental cause for this serious business failure is the absence of a corporate sustainability strategy as occurs in numerous examples in developing countries. Based on this thesis‘ aim, objectives, hypotheses and questions, the action research (AR) study has adopted a mixed methods research strategy as the most appropriate method for this case study. It incorporates both a quantitative and a qualitative research type in sequential order through a questionnaire survey of change agent employees followed by semi-structured interviews with senior managers of the firm under scrutiny. The research study‘s findings prove the study‘s hypotheses and answer the research questions. This AR study has contributed to the body of knowledge through actionable knowledge presented in developed a ‗‗green‘ strategy for the adoption of triple bottom line corporate sustainability (TBLCS) that should guarantee incorporate economic prosperity, social responsibility and environmental stewardship, and meet stakeholders‘ ever growing demands and interest in ‗green‘ business. The developed green strategy has five drivers: green transformational iii leadership (GTL), green organisational culture, employees‘ engagement, learning organisation, and dedicated corporate social responsibility (CSR). The actionable knowledge has further demonstrated a feasible and practical mechanism for adopting and executing a TBLCS strategy through the proposed business ‗green‘ model and a dedicated actionable roadmap that should guarantee the corporate a successful strategic transformational shift to a sustainable green business. Keywords: Corporate sustainability, triple bottom line, green transformational leadership, green culture, employee engagement, learning organisation, CSR, UAE

Optimized Resource-Constrained Method for Project Schedule Compression

Construction projects are unique and can be executed in an accelerated manner to meet market conditions. Accordingly, contractors need to compress project durations to meet client changing needs and related contractual obligations and recover from delays experienced during project execution. This acceleration requires resource planning techniques such as resource leveling and allocation. Various optimization methods have been proposed for the resource-constrained schedule compression and resource allocation and leveling individually. However, in real-world construction projects, contractors need to consider these aspects concurrently. For this purpose, this study proposes an integrated method that allows for joint consideration of the above two aspects. The method aims to optimize project duration and costs through the resources and cost of the execution modes assigned to project activities. It accounts for project cost and resource-leveling based on costs and resources imbedded in these modes of execution. The method's objective is to minimize the project duration and cost, including direct cost, indirect cost, and delay penalty, and strike a balance between the cost of acquiring and releasing resources on the one hand and the cost of activity splitting on the other hand. The novelty of the proposed method lies in its capacity to consider resource planning and project scheduling under uncertainty simultaneously while accounting for activity splitting. The proposed method utilizes the fuzzy set theory (FSs) for modeling uncertainty associated with the duration and cost of project activities and genetic algorithm (GA) for scheduling optimization. The method has five main modules that support two different optimization methods: modeling uncertainty and defuzzification module; scheduling module; cost calculations module; sensitivity IV analysis module; and decision-support module. The two optimization methods use the genetic algorithm as an optimization engine to find a set of non-dominated solutions. One optimization method uses the elitist non-dominated sorting genetic algorithm (NSGA-II), while the other uses a dynamic weighted optimization genetic algorithm. The developed scheduling and optimization method is coded in python as a stand-alone automated computerized tool to facilitate the needed iterative rescheduling of project activities and project schedule optimization. The developed method is applied to a numerical example to demonstrate its use and to illustrate its capabilities. Since the adopted numerical example is not a resource-constrained optimization example, the proposed optimization methods are validated through a multi-layered comparative analysis that involves performance evaluation, statistical comparisons, and performance stability evaluation. The performance evaluation results demonstrated the superiority of the NSGA-II against the dynamic weighted optimization genetic algorithm in finding better solutions. Moreover, statistical comparisons, which considered solutions’ mean, and best values, revealed that both optimization methods could solve the multi-objective time-cost optimization problem. However, the solutions’ range values indicated that the NSGA-II was better in exploring the search space before converging to a global optimum; NSGA-II had a trade-off between exploration (exploring the new search space) and exploitation (using already detected points to search the optimum). Finally, the coefficient of variation test revealed that the NSGA-II performance was more stable than that of the dynamic weighted optimization genetic algorithm. It is expected that the developed method can assist contractors in preparation for efficient schedule compression, which optimizes schedule and ensures efficient utilization of their resources

Oscillation behavior of second order nonlinear neutral differential equations with deviating arguments

Oscillation criteria are established for second order nonlinear neutral differential equations with deviating arguments of the form $$r(t)\psi(x(t))|z'(t)|^{\alpha -1} z'(t)+ \int_a^b q(t,\xi)f(x(g(t,\phi)))d\sigma (\xi) =0,\quad t\gt t_0,$$ where $\alpha \gt 0$ and $z(t)= x(t)+p(t)x(t-\tau)$. Our results improve and extend some known results in the literature. Some illustrating examples are also provided to show the importance of our results

PESTEL and 3R Waste Management Model for Construction Companies Operating in Central Tanta: A Comprehensive Construction and Demolition Waste Management Model

Due to a recent economic boom, Tanta\u27s construction sector has seen fast expansion, which has resulted in high construction and demolition waste (C&DW) creation and waste management operations that lag below international best practices. The current study uses PESTEL analysis, a thorough environmental screening method, to first identify and evaluate significant external and internal elements that may have an impact on C&DW management in a top Central Egyptian construction business. Then, this firm is the topic of a case study that applies the 3R (reduce-reuse- recycle) principles. The offered context-specific current international practices, the described current firm practices, and the applied changes are prioritized improvements with inferred sustainability advantages are recommended. The conclusions and suggestions are particularly relevant to other Tanta construction firms that wish to guarantee more environmentally friendly C&DW management operations in the future

Impact of Covid-19 third wave Omicron in India

The new Covid-19 variant omicron remains a cause of concern as India is seeing a sudden spike in the number of cases related to the highly transmissible coronavirus variant that has fuelled record outbreaks in various countries in the world.Day by day the cases increases reported by union Ministry of Health and family Welfare at the end of 2021. In this study we came to a approach that omicron variant is not severe and less harmful effect in comparison of second wave in India and there is no need for more hospitalization and lockdown for this with the fact knowing that we got 80 % vaccination

Challenges for the Use of Local Materials in Unbound Road Subbase in Qatar

Current practice in Qatar is to blend local limestone with dune sand for use in unbound pavement applications. Dune sand is used to improve the properties of fine aggregate and compliance with the QCS 2014 requirements of plasticity and sand equivalent. The material has been successfully used for many years but currently facing the challenge of limited dune sand supply and recent government restrictions on its use in construction. The paper presents data on the properties of limestone obtained from different sources, tested in accordance with the QCS 2014 requirements. Variation of limestone source and the presence of clay particles greatly affected its suitability for use in unbound pavement applications. Improvement could be achieved by adjusting the grading of the material. Recommendations are made to revise the QCS 2014 specifications within the context of international specifications, when the unbound material is placed in a dry environment and away from the water level to enhance the wider utilization of local materials and sustainable construction in Qatar