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This study aims to focus on the main materials used in consolidation processes of illuminated paper manuscripts and leather binding.

For each material, chemical structure, chemical composition, molecular formula, solubility, advantages, disadvantages and its role in treatment process are presented.

This study concluded that carboxy methyl cellulose, hydroxy propyl cellulose, methyl cellulose, cellulose acetate, nanocrystalline cellulose, funori, sturgeon glue, poly vinyl alcohol, chitosan, chitosan nanoparticles (NPs), gelatin, aquazol, paraloid B72 and hydroxyapatite NPs were the most common and important materials used for the consolidation of illuminated paper manuscripts. For the leather bindings, hydroxy propyl cellulose, polyethylene glycol, oligomeric melamine-formaldehyde resin, acrylic wax SC6000, pliantex, paraloid B67 and B72, silicone oil and collagen NPs are the most consolidants used.

Illuminated paper manuscripts with leather binding are considered one of the most important objects in libraries, museums and storehouses. The uncontrolled conditions and other deterioration factors inside the libraries and storehouses lead to degradation of these artifacts. The brittleness, fragility and weakness are considered the most common deterioration aspects of illuminated paper manuscripts and leather binding. Therefore, the consolidation process became vital and important to solve this problem. This study presents the main materials used for consolidation process of illuminated paper manuscripts and leather bindings.

This paper aims to present the components' characterization and condition assessment of an important deteriorated Mamluk-illuminated paper manuscript housed in Al-Azhar Library, Egypt.

Different analytical techniques used in this study were the portable digital optical microscope, stereomicroscope, scanning electron microscope with EDX (SEM.EDX), portable X-ray fluorescence (pXRF), X-ray diffraction (XRD), pH measurement and Fourier transform infrared spectroscopy (FTIR).

The results obtained by different microscopes showed that the gilding in the surface of illuminated paper sheets was performed with gold leaves. Additionally, these microscopes revealed that the illuminated paper manuscript has different aspects of deterioration such as adhered dirt, staining, some micro-cracks, cracks and detachment of some parts in some illuminated areas. The results of elemental analysis by EDX, portable XRF and XRD analysis showed that the orange red pigment is red lead (Pb₃O₄), blue pigment is azurite (2CuCo₃.Cu (OH)₂), and the gold layer is has consisted of brass alloy (Cu-Zn) with a small amount of gold element (Au). The pH measurement stated that the historical paper in the acidity level. The ATR-FTIR analysis also revealed the oxidation of cellulose. Moreover, it was found from ATR-FTIR that Arabic gum was used as a binder for the pigments.

This study presents the important results of analytical methods used for condition assessment and identification of the components of an important Mamluk-illuminated paper manuscript, where these results referred that the studied paper manuscript had different aspects of deterioration. The conservation steps either conservation treatment or preventive conservation are urgently needed in future studies.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

The purpose of this study is to develop a new parallel metaheuristic algorithm for solving unconstrained continuous optimization problems.

The proposed method brings several metaheuristic algorithms together to form a coalition under Weighted Superposition Attraction-Repulsion Algorithm (WSAR) in a parallel computing environment. The proposed approach runs different single solution based metaheuristic algorithms in parallel and employs WSAR (which is a recently developed and proposed swarm intelligence based optimizer) as controller.

The proposed approach is tested against the latest well-known unconstrained continuous optimization problems (CEC2020). The obtained results are compared with some other optimization algorithms. The results of the comparison prove the efficiency of the proposed method.

This study aims to combine different metaheuristic algorithms in order to provide a satisfactory performance on solving the optimization problems by benefiting their diverse characteristics. In addition, the run time is shortened by parallel execution. The proposed approach can be applied to any type of optimization problems by its problem-independent structure.

The oil and gas construction projects are affected negatively by the drop in oil price in recent years. Thus, most engineering, procurement and construction (EPC) companies are opting to optimize the project mainly to mitigate the source of risks in construction to achieve the project expectation. Risk factors cause a threat to the project objectives regarding time, cost and quality. It is additionally a vital component in deviating from the client's expectation of productivity, safety and standards. This research aims to investigate the causes of risk in the oil and gas construction projects in Yemen.

A comprehensive literature review from various sources including books, conference proceedings, the Internet project management journals and oil and gas industry journals was conducted to achieve the objectives of this study. This initial work was predicated strictly on a literature review and the judgments of experts to develop the risk factor framework for the oil and gas construction projects in Yemen.

The authors found a few studies related to risk factors in oil and gas construction projects and shared a similar view about general construction projects. However, only a fraction of the factors accepted have included the variances of other studies on a regional basis or specific countries, such as the Yemen situation, due to the differences between the general construction industry and oil and gas industry. Moreover, the factors of these attributes were still accepted due to their applicability to the oil and gas industry, and no significant variances existed between countries. Research has indicated that 51 critical factors cause risks in the oil and gas construction projects in Yemen. Such risk factors can be divided into two major groups: (1) internal risk factors, including seven critical sources of risks, namely client, contractor, consultant, feasibility study and design, tendering and contract, resources and material supply and project management; and (2) external risk factors, including six sources of critical risk factors, namely national economic, political risk, local people, environment and safety, security risk and force-majeure-related risk factors. A risk factor framework was developed to identify the critical risk factors in the oil and gas construction projects in Yemen.

This research was limited to the oil and gas construction projects.

Practically, this study highlights the risk factors that cause a negative effect on the success of oil and gas construction projects in Yemen. The identification of these factors is the first step in the risk management process to develop strategic responses for risks and enhance the chances of project success.

The identification of risks factors that cause the failure of construction projects helps develop response strategies for these risks, thereby increasing the chances of project success reflected in the oil and gas sector, which is a main tributary of the national economy in developing countries.

This research is the pioneer for future investigations into this vital economic sector. Given the lack of resources and studies in the field of construction projects for the Yemeni oil and gas sector, the Yemeni government, oil companies and researchers in this field are expected to benefit from the results of this study. The critical risk factors specific to the oil and gas construction projects in Yemen should be further investigated with focus only on Yemen and its oil and gas industry players.

The purpose of this article is to present a mathematical model for the fully developed flow of Bi-viscous Bingham nanofluid through a uniform-width anisotropic porous channel. The model incorporates a generalized Brinkman-Darcy formulation for the porous layers while considering the motion of nanoparticles influenced by both Brownian diffusion and thermophoresis effects.

The similarity transformations derived through Lie group analysis are used to reduce the system from nonlinear partial differential equations to nonlinear ordinary differential equations. The finite difference method-based numerical routine bvp4c is employed to collect and graphically present the outcomes for velocity, temperature, and nanoparticle concentration profiles. The flow pattern is analyzed through streamlined plots. Furthermore, skin friction, heat, and mass transmission rates are investigated and presented via line plots.

It is observed that in anisotropic porous media, the temperature profile is stronger than in isotropic porous media. The thermal anisotropic parameter enhances the concentration profile while reducing the temperature.

Anisotropy arises in various industrial and natural systems due to factors such as preferred orientation or asymmetric geometry of fibers or grains. Hence, this study has applications in oil extraction processes, certain fibrous and biological materials, geological formations, and dendritic zones formed during the solidification of binary alloys.

1. The permeability and thermal conductivity are not constant; instead, they have different values in the x and y directions. 2. This study considers the dependency of thermophoresis on nanoparticle volume fraction and Brownian diffusion on the temperature in both the fluid flow equations and boundary conditions. 3. A novel similarity transformation is derived using Lie group analysis instead of using an existing transformation already available in the literature.

Project failure is the result of one or a combination of several causes of risk factors that are very important to identify for effective performance. This study aims to focus on studying the fundamental relationship between internal risk factors and the negative effect on oil and gas project success in Yemen using the partial least square structural equation modelling (PLS-SEM) method.

Data collection was carried out using a formal questionnaire survey of the oil field sector in Yemen by companies involved in mega-oil and gas construction projects. A hierarchical model for determining causative internal risk factors and their effects was developed and evaluated using SEM method by SmartPLS3 software technology.

The findings of analyzing model indicate that all categories have a significant effect on project success, while the most significant affected categories in the internal risk factors are project management factors, feasibility study-design and resources-material supply with a path coefficient value of 0.213, 0.197 and 0.186, respectively. Moreover, for the hypotheses test, the positive relationship means that all experimental hypotheses are accepted according to path coefficient value analysis. In addition, the internal risk factors research model shows the ranking of effects on project success starting with project stoppage (loading factor 0.841), cost overruns (loading factor 0.818), time overruns (loading factor 0.726) and project target failure with loading factor 0.539.

The research was limited to the oil and gas construction projects in Yemen.

Interpreting the relationship between internal risk factors and their impact on the success of construction projects in the oil and gas sector will assist project team and oil companies in developing risk response strategies and developing appropriate plans to mitigate the effects of risks, which is presented in this paper.

The paper explains the relationship between cause and effect of internal risk factors in oil and gas projects in Yemen, and is expected to be a guideline for the oil companies and future academic research in the risk management area.

The impact of the coronavirus disease 2019 (COVID-19) pandemic on architectural education (AE) was investigated, and a framework was proposed to reduce the impacts' negative consequences.

Systematic literature review, bibliometric and content analyses were combined to gain an in-depth understanding of the effects of the pandemic on AE and projections for its future. Relevant documents were extracted from the Web of Science (WoS) database. Bibliometric connections in the context of AE and COVID-19 pandemic were explored using text-mining and content analysis was performed.

The challenges, development tendencies and collaboration networks in AE during the pandemic were quantitatively and qualitatively analyzed. The most influential articles, journals, authors and countries/regions were highlighted using a bibliometric analysis. The analysis of keyword tendencies and clusters indicates that new concepts have emerged in AE research during the pandemic involving online, in-person and hybrid education. Using content analysis of 57 subtopics, 39 (18) were categorized as having negative (positive) effects. A comprehensive mitigation framework was designed to reduce the impact of the pandemic on AE.

The study findings can enable practitioners to construct effective solutions to COVID-19- and other disaster-related problems regarding AE. The implications, obstacles and mitigation framework presented can help identify gaps in the literature and guide further research.

This paper presents the first bibliometric and content analysis of AE and COVID-19 pandemic-related studies published from January 2020 to June 2022 to highlight several research directions and academic development within the field.

The widespread uptake of digital technology tools for online teaching and learning reached its peak during the nationwide lockdown triggered by the COVID-19 pandemic. It transformed the higher education institutions (HEIs) marketplace both in developed and developing countries. However, in this process of digital transformation, several HEIs, specifically from developing countries, faced major challenges. That threatened to affect their sustainability and performance. In this vein, this study conducts a bibliometric review to map the challenges during the COVID-19 pandemic and suggest strategies for HEIs to cope with post-pandemic situations in the future.

This comprehensive review encompasses 343 papers published between 2020 and 2023, employing a systematic approach that combines bibliometrics and content analysis to thoroughly evaluate the articles.

The investigation revealed a lack of published work addressing the specific challenges faced by the faculty members affecting their well-being. The study underscores the importance of e-learning technology adoption for higher education sustainability by compelling both students and teachers to rely heavily on social media platforms to maintain social presence and facilitate remote learning. The reduced interpersonal interaction during the pandemic has had negative consequences for academic engagement and professional advancement for both educators and students.

This has implications for policymakers and the management of HEIs, as it may prove useful in reenvisioning and redesigning future curricula. The paper concludes by developing a sustainable learning framework using a blended approach. Additionally, we also provide directions for future research to scholars.

This study has implications for policymakers and HEI management to rethink the delivery of future courses with a focus on education and institute sustainability. Finally, the research also proposes a hybrid learning framework for sustainability and forms a robust foundation for scholars in future research.

Influential factors attributed to causing project completion delay (PCD) differ because of prevailing variability of local conditions. Construction projects specifically in Yemen (and other developing countries) experience devastating effects of PCD which include litigation, cost overrun, arbitration, abandonment and failure. While existing works have investigated the causes and effects of PCD, not much exist on approaches to optimizing its occurrence in Yemen. In a bid to enhance the effects of PCD in Yemen, the integrated influential factors (IIFs), which is a construction-party specific model, was developed to mitigate the effects of PCD in Yemen. As a build up to the development of this model, this paper aims to validate the IIFs model with a view to foster its application to enhance PCD in construction project delivery in Yemen.

The validation of the IIFs model was done through seeking the opinions of 12 selected construction industry experts. This involved using a structured questionnaire to seek information on the sustainability of implementing the IIFs model.

The findings revealed that if the IIFs model is vigorously implemented, it would go a long way in curbing delay in the delivery of construction projects, making construction delivery less risky due to the effects of delay.

The study is limited to only influential factors of internal stakeholders of the construction phase. Similarly, the study was only conducted in the state of Sana'a, Yemen. The implication of the adoption of the IIFs model is that it can hopefully serve as an adaptive controller to construction project delivery relative to the specific parameters and factors investigated in this study.

The IIFs model is a novel approach to optimizing PCD in Yemen specific to both the construction-phase and internal stakeholders. Existing studies on PCD in Yemen, although investigating the causes and effect of PCD, hardly proffer any approach to optimizing PCD for successful construction project delivery.