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The purpose of this paper is to study the dynamical properties of a rotating rigid body (RB) containing a viscous incompressible fluid.

The Reynolds number is assumed to be small so that the governing equations can be easily obtained, and the asymptotic technique is used to solve the problem.

The effects of the various body parameter values on the motion’s behavior are theoretically elucidated, which can be used for optimization of the charged RB.

This paper finds the missing piece of the puzzle when it comes to the rotating RB containing a viscous fluid; it clearly elucidates graphically how the body parameters affect its dynamical properties.

This study aims to represent a successful simple method for the synthesis of some novel dyes based on thiazole derivatives and their applications in textile printing.

2-(benzo[d]thiazol-2-ylmethyl)thiazol-4(5H)-one compound is prepared by convention heating and microwave technique then used as a coupling agent, which reacts with different diazonium Salt to form diazo dyes.

The synthesized diazo dyes are confirmed via spectral data (IR,1H-NMR, 13C-NMR and Mass spectra). The dyes are used to print polyester fabric. The obtained results clarified that the prints have good color strength, brilliant color and highly durable antibacterial activity.

The authors designed efficient synthesis for some novel thiazolone dyes. The novel procedure features short-reaction time, very good yields and a simple workup. The authors studied the antibacterial activity and their application in printing polyester fabrics.

The centralized, command models emphasized social welfare and equity, whereas in free market conditions, the market participants are primarily governed by the demand and supply factors and their objective of wealth maximization. The tension between these two approaches is most evident in the structure and organization of financial markets. This paper presents an analysis and examination of the feasibility of the commonweal principle in free market environments and offers a preliminary empirical approach to investigate this issue further.

Calcium and Zinc lignates were proven to be good antioxidants for rubber composites. The purpose of this paper is to evaluate the copper lignate antioxidant activity along with evaluating its electrical conductivity in rubber composites.

The antioxidant activity of the Cu-LSF complex was compared with that of standard commercial antioxidant additives as a green alternative. The rheological characteristics, thermal aging and mechanical and electrical properties were evaluated for the NBR vulcanizates containing the different antioxidants in the presence or absence of coupling agents.

Results revealed that the Cu-LSF complex (5 phr) can function as a compatibilizing, antioxidant and electrical conductivity agent.

The new copper complex prepared from paper-pulping black liquor of wastes could be used as a green antioxidant and electrical conductivity agent in rubber composites.

In continuation to the previous work on copper (lignin/silica/fatty acids) (Cu-LSF) complex as a natural antioxidant/electrical conductivity agent for nitrile-butadiene rubber (NBR), this study aims to perform further investigations for NBR vulcanizates loaded with different concentrations of Cu-LSF complex, including swelling behavior and hardness properties, as well as evaluating their thermal stability via thermogravimetric analysis.

The behavior of Cu-LSF complex in NBR matrix was compared with that of the standard commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline/N-isopropyl-N′-phenyl-p-phenylenediamine [TMQ/IPPD]).

Results revealed that Cu-LSF complex can act as an effective reinforcing and hardening agent, with exhibiting fluid resistance, even when compared with the commercial antioxidants. In comparison with the previous studies on its Zn and Ca analogues and their behavior in different rubber matrixes, Cu-LSF complex showed higher values of hardness and less susceptibility for swelling, respectively. Moreover, Cu-LSF antioxidant activity becomes in accordance with the previous work.

The new Cu-LSF complex could be used as a green alternative to the commercial antioxidants (TMQ/IPPD) with introducing further advantages to the rubber matrix, such as hardening, fluid resistance and thermal stability.

This study aims to investigate the behavior of the green biomass-derived copper (lignin/silica/fatty acids) complex, copper lignin/silica/fatty acids (Cu-LSF) complex, when incorporated into the nonpolar ethylene propylene diene (EPDFM) rubber matrix, focusing on its reinforcing and antioxidant effect on the resulting EPDM composites.

The structure of the prepared EPDM composites was confirmed by Fourier-transform infrared spectroscopy, and the dispersion of the additive fillers and antioxidants in the EPDM matrix was investigated using scanning electron microscopy. Also, the rheometric characteristics, mechanical properties, swelling behavior and thermal gravimetric analysis of all the prepared EPDM composites were explored as well.

Results revealed that the Cu-LSF complex dispersed well in the nonpolar EPDM rubber matrix, in thepresence of coupling system, with enhanced Cu-LSF-rubber interactions and increased cross-linking density, which reflected on the improved rheological and mechanical properties of the resulting EPDM composites. From the various investigations performed in the current study, the authors can suggest 7–11 phr is the optimal effective concentration of Cu-LSF complex loading. Interestingly, EPDM composites containing Cu-LSF complex showed better antiaging performance, thermal stability and fluid resistance, when compared with those containing the commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline and N-isopropyl-N’-phenyl-p-phenylenediamine). These findings are in good agreement with our previous study on polar nitrile butadiene rubber.

The current study suggests the green biomass-derived Cu-LSF complex to be a promising low-cost and environmentally safe alternative filler and antioxidant to the hazardous commercial ones.

In this paper, Isoparametric finite element formulations are derived for special elements for representing the steel‐concrete interface. Curved multi‐noded Isoparametric element for reinforcing steel idealization is proposed. In addition, special thin Isoparametric element in a form of a sheath is suggested in order to model the bond‐slip characteristics. Special provisions are taken into account to avoid numerical difficulties. The proposed elements are incorporated in non‐linear finite element program DMGPLSTS and applied to the problem of tension stiffening of reinforced concrete members. The results are noted to reflect a softer overall response attributable to the slip effect.

This chapter explores the rise of Public Private Partnerships (PPPs) in global education policy through theories of neoliberal globalization and analyzing the practices of international organizations that help to frame and establish such policies in various countries such as Egypt. PPPs have been a vehicle for promoting the involvement of transnational corporations, especially in the information and communication technology (ICT) sector, in education sector reforms. The chapter examines the case of Egypt and the role of internal and external actors in promoting educational reform, spearheaded by the largest PPP: the Egyptian Education Initiative. The chapter questions the relevance and impact of such education reforms in the unstable political, economic, and social environment of post-revolution Egypt.

The purpose of this paper is to investigate the potential quality of Kamut® (triticum turgidum turanicum) as an ancient relative of modern durum wheat for food preparation and Egyptian consumption.

The methodology included in this paper is based on quality evaluation of Kamut wheat of the Dashure-Fayume geographical origin physically, chemically and technologically compared to Beni Suef 1, Beni Suef 3 and Suhag 3, the most dominant durum varieties in Egypt. After that, producing a specific end product (traditional couscous) regarded the critical quality aspects in Kamut wheat.

The results obtained showed that Kamut grains had higher physical properties indicating higher milling yield potential. Besides, Kamut flour was remarkable with higher protein and oil content. The use of a farinograph for assessing the rheological properties of Kamut dough has proven a useful quality for its measured characteristics compared to the Egyptian durum varieties. The good physical and rheological properties, coupled with high protein content, validated that Kamut is a valuable addition to the Egyptian diet and suited for the production of pasta and/or couscous. The sensory attributes of traditional couscous were significantly (p < 0.05) highly acceptable to the panelists.

These results lead to valuable addition and improvement of the Egyptian diet which consider The Sustainable Agricultural Development Strategy (SADS) towards 2030 in Egypt based on achieving higher rates of food security in strategic goods in regard to improve food quality and safety, especially Kamut wheat which produces high quality grains without artificial fertilizers and pesticides.

The chapter explores the impact of the global knowledge economy upon education and social reform programmes in the Middle East. It highlights the difficulty of modifying school curricula to accord with a view of education which is based upon human capital formation coupled with standardised testing regimes designed to accommodate performativity; both of these phenomena being products of a neo-liberal agenda of the global north. The narrative considers the contrasting perspectives of regionally based Arab commentators, and it demonstrates the difficulty of reconciling the passionately held convictions of those who shun the modernist project with those who wish to embrace the democratic and social values of the global north. From his first-hand experience of government schools in the region, the author concludes with a plea for the formulation of education reforms which may succeed through more closely reflecting the cultural and educational traditions of the region rather than by the wholesale imposition of western values.