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The purpose of this study is to examine how well reinforced concrete structures can be shielded against concrete carbonation using anti-carbonation coatings based on synthetic polymer.

Applying free radical polymerization, an acrylate terpolymer emulsion that a surfactant had stabilized was created. A thermogravimetric analysis, minimum film-forming temperature, Fourier transform infrared spectroscopy and particle size distribution are used to characterize the prepared eco-friendly water base acrylate terpolymer emulsion. Using three different percentages of the acrylate terpolymer emulsion produced, 35%, 45% and 55%, the anti-carbonation coating was formed. Tensile strength, tensile strain, elongation, crack-bridging ability, carbon dioxide permeability, chloride ion diffusion, average pull-off adhesion strength, water vapor transmission, gloss, wet scrub resistance, QUV/weathering and storage stability are the characteristics of the anti-carbonation coating.

The formulated acrylate terpolymer emulsion enhances anti-carbonation coating performance in CO₂ permeability, Cl-diffusion, crack bridging, pull-off adhesion strength and water vapor transmission. The formed coating based on the formulated acrylate terpolymer emulsion performed better than its commercial counterpart.

To protect the steel embedded in concrete from corrosion and increase the life span of concrete, the surface of cement is treated with an anti-carbonation coating based on synthetic acrylate terpolymer emulsion.

In addition to saving lives from building collapse, it maintains the infrastructure for the long run.

The anti-carbonation coating, which is based on the synthetic acrylate terpolymer emulsion, is environmentally benign and stops the entry of carbon dioxide and chlorides, which are the main causes of steel corrosion in concrete.

The purpose of the paper is to showcase the significant achievements of Egypt's scientists in the 20th century across various fields of study such as medicine, physics, chemistry, biology, math, geology, astronomy and engineering. The paper highlights the struggles and successes of these scientists, as well as the cultural, social and political factors that influenced their lives and work. The aim is to inspire young people to pursue careers in science and make their own contributions to society by presenting these scientists as role models for hard work and dedication. Ultimately, the paper seeks to promote the importance of science and its impact on society.

The purpose of this review is to present the scientific biographies of Egypt's most distinguished scientists, primarily in the field of Natural Sciences, in a balanced and comprehensive manner. The work is objective, honest and abstract, avoiding any bias or exaggeration. The author provides a clear and concise methodology, including a brief introduction to the scientist and their field of study, an explanation of their major contributions, the impact of their work on society, any challenges or obstacles faced during their career and their lasting legacy. The aim is to showcase the important achievements of these scientists, their impact on their respective fields and to inspire future generations to pursue scientific careers.

The group of outstanding scientists in 20th century Egypt were shaped by various factors, including familial upbringing, education, society, political and cultural atmosphere and state support for scientific research. These scientists made significant contributions to various academic disciplines, including medicine, physics, chemistry, biology, mathematics and engineering. Their impact on their communities and cultures has received international acclaim, making them role models for future generations of scientists and researchers. The history of these scientists highlights the importance of educational investments and supporting scientific research to foster innovation and social progress. The encyclopedia serves as a useful tool for students, instructors and education professionals, preserving Egypt's scientific heritage and honouring the scientists' outstanding accomplishments.

The encyclopedia preserves Egypt's scientific heritage, which has been overlooked for political or other reasons. It is a useful tool for a variety of readers, including students, instructors and education professionals, and it offers insights into universally relevant scientific success factors as well as scientific research methodologies. The encyclopedia honours the outstanding scientific accomplishments of Egyptian researchers and their contributions to the world's scientific community.

The practical implications of this paper are several. First, it highlights the importance of education, family upbringing and societal support for scientific research in fostering innovation and social progress. Second, it underscores the need for continued funding and support for scientific research to maintain and build upon the accomplishments of past generations of scientists. Third, it encourages young people to pursue scientific careers and make their own contributions to society. Fourth, it preserves the scientific heritage of Egypt and honors the contributions of its outstanding scientists. Finally, it serves as a useful tool for students, instructors and education professionals seeking to understand the factors underlying scientific success and research methodologies.

The social implications of the paper include promoting national pride and cultural identity, raising awareness of the importance of education and scientific research in driving social progress, inspiring future generations of scientists and researchers, reducing socioeconomic disparities and emphasizing the role of society, politics and culture in shaping scientific researchers' personalities and interests.

The paper's originality/value lies in its comprehensive documentation of the scientific biographies of Egypt's most prominent scientists in the 20th century, providing unique insights into the factors that contributed to their development and their impact across various academic disciplines. It preserves Egypt's scientific heritage and inspires future generations of scientists and researchers through the promotion of educational investments and scientific research. The encyclopedia serves as a useful tool for education professionals seeking to understand scientific success factors and research methodologies, emphasizing the importance of supportive and inclusive environments for scientific development.

This study aims to extend the pot life without altering the qualities and performance of the coating, which is important to increase when manufacturing polyurethane coatings.

An acrylic polyol from a mixture of different monomers of hydroxypropyl methacrylate, methacrylic acid, 2-ethylhexyl acrylate, methyl methacrylate and n-butyl methacrylate was prepared with different ratios of 2,4-pentanedione as a pot life extender. The reaction takes place in presence of di-tert-butyl peroxide as initiator with samples (T1–T7). The physical properties of prepared acrylic polyol were characterized. Then, coating polyurethane varnish was prepared from the prepared acrylic polyol with an aliphatic polyisocyanate in a 1:1 equivalent ratio of OH:NCO at room temperature, in presence of paint thinner (diluents/solvent) and dibutyltin dilaurate as a catalyst to give samples (T1C–T7C). This coating was evaluated via Fourier-transform infrared spectroscopy, drying time, hardness and gloss, distinctness of image and reflected image quality.

The coating has a prolonged pot life while still maintaining the other qualities, thanks to the greater 2,4-pentanedione content.

It is desired to have a paint which has a satisfactory pot life, short curing time and reduces many drawbacks such as inefficient working and deterioration of the paint before application.

Data protection requirements heavily increased due to the rising awareness of data security, legal requirements and technological developments. Today, NoSQL databases are increasingly used in security-critical domains. Current survey works on databases and data security only consider authorization and access control in a very general way and do not regard most of today’s sophisticated requirements. Accordingly, the purpose of this paper is to discuss authorization and access control for relational and NoSQL database models in detail with respect to requirements and current state of the art.

This paper follows a systematic literature review approach to study authorization and access control for different database models. Starting with a research on survey works on authorization and access control in databases, the study continues with the identification and definition of advanced authorization and access control requirements, which are generally applicable to any database model. This paper then discusses and compares current database models based on these requirements.

As no survey works consider requirements for authorization and access control in different database models so far, the authors define their requirements. Furthermore, the authors discuss the current state of the art for the relational, key-value, column-oriented, document-based and graph database models in comparison to the defined requirements.

This paper focuses on authorization and access control for various database models, not concrete products. This paper identifies today’s sophisticated – yet general – requirements from the literature and compares them with research results and access control features of current products for the relational and NoSQL database models.

Sustainability development goals (SDGs) cannot be achieved without a concerted effort from businesses and other organisations, being the corporate level is one of the keys to the achievement of SDGs. This study aims to explore the relationship between firms' adoption of SDG reporting in China and two main corporate-level factors, namely, board characteristics and ownership factors. Also, this study aims to determine which set of drivers – those related to board or ownership factors – exerts a greater influence on this reporting.

This research examines the impact of ownership and board-level factors on the SDG reporting of Chinese firms in the period 2016–2018, with a final sample of 455 firm-year observations operating in 11 activity sectors.

The results support the following: firstly, that board independence and size and the existence of a corporate social responsibility (CSR) committee favours firms addressing SDGs in their sustainability reporting while greater levels of foreign or institutional ownership are negatively related to a company's adoption of SDG reporting; secondly, two-stage logit regression results revealed that board-level factors exert greater explanatory power in the prediction of this reporting and have bigger weights in affecting the SDGs reporting.

This study focuses on assessing the drivers of SDGs; namely, what internal factors will facilitate companies' better implementation of SDG reporting to bridge the gap in this field, not only extending the investigation of corporate governance factors affecting SDGs but also examining the impact of corporate ownership on SDG reporting.

This study enriches and provides support for previous studies examining the drivers of SDGs in the private sector. In academia, addressing SDGs in business is still an emerging research stream that is still in an embryonic state; the reporting of SDGs in business is quite under-investigated in the sustainability literature. Moreover, literature on the drivers that promote better implementation of SDGs in business is even more scarce and incomplete. Some previous studies have ignored the impact of board size and the CSR committee. At the same time, there is no research to date on the impact of ownership on companies' SDGs reporting, which has been proved to play a large role in firms sustainability reporting.

This study aims to systematically consolidate and quantitatively integrate the mixed empirical results on the association between ownership mechanisms and voluntary carbon disclosure using meta-analysis and further propose potential country-level moderators of this relationship.

The authors apply meta-analytic procedures on 55 empirical studies conducted during 2008–2022, covering 13 countries, 85 effect sizes and 226,473 firm-year observations. To gauge the significance of the estimated mean effect size, a random-effects Hedges and Olkin meta-analysis procedure is adopted, followed by a restricted maximum likelihood based meta-regression, to test the effect of possible moderators.

Aligned with agency and stakeholder theories, the results highlight institutional and state ownership (SO) as having a significant positive impact on voluntary carbon disclosure. On the other hand, ownership concentration, managerial and foreign ownership have an insignificant effect on voluntary carbon disclosure. Based on institutional theory perspectives, the authors confirm the impact of institutional ownership on voluntary carbon disclosure to be more prominent in civil law countries and those countries that have implemented an emission trading scheme (ETS).

The finding that institutional and SO in firms can translate into higher voluntary disclosures deems investors and the government as crucial stakeholders in achieving carbon neutrality. Furthermore, the finding that the effect of institutional investors on carbon disclosure is heightened in ETS-implemented countries provides evidence to the regulatory authorities in favour of this scheme.

The positive impact of institutional and government ownership on voluntary carbon disclosure highlights that these ownership structures not only have the potential to transform corporate decisions but also have implications for the wider society. As firms owned by institutional investors disclose their carbon information, it provides access to critical information about their environmental practices to the public. This fosters an environment of transparency and trust between the firm and its stakeholders (the community), leading to an overall well-informed society.

While prior meta-reviews studied the impact of corporate governance on voluntary disclosures, the meta-literature, as of 2024, has yet to address its influence specifically on carbon disclosures, which are pertinent amidst the ongoing global climate change crisis. The findings inform policymakers about the pivotal institutional factors that can amplify the impact of effective ownership structures on voluntary carbon disclosure. Future scope exists for investigating the effects of ownership mechanisms on firm-level sustainable investments. Furthermore, future empirical analysis could consider the moderating influence of “culture” and “ease of doing business” on the ownership-carbon disclosure relationship.

Financial market sustainability is gaining attention as investors and stakeholders become more aware of environmental, social and governance issues, pushing demand for responsible and ethical investment practices. Therefore, this study aims to investigate the impact of carbon (CO2) emissions from three sources, oil, gas and coal, on the stock market sustainability via effective government policies.

The eight countries belong to two different regions of world: Asian economies such as Pakistan, India, Malaysia and China, and OECD economies such as Germany, France, the UK and the USA are selected as a sample of the study. The 22-year data from 2000 to 2022 are collected from the DataStream and the World Bank data portal for the specified countries. The generalized methods of movement (GMM) and wavelet are used as the econometric tool for the analysis.

Our findings show that the CO2 emission from coal and gas significantly negatively impacts stock market sustainability, but CO2 emission from oil positively impacts stock market sustainability. Moreover, all the emerging Asian economies’ CO2 emissions from coal and gas have a much greater significant negative impact on the stock market sustainability than the OECD countries due to the critical situation. However, the government’s effective policies have a positive significant moderating impact between them, reducing the effect of CO2 emission on the stock market.

This study advocated strong implications for policymakers, governments and investors.

Effective government policies can protect the environment and make business operations suitable, leading to market financial stability. This study advocated strong implications for policymakers, governments and investors.

This study provides fresh evidence of the government’s effective role to control the carbon environment that provide the sustainability to the organizations with respect to OECD and emerging economy.

This research paper aims to examine the influence of greater female participation on the board of directors on the environmental transparency of companies.

To achieve the purpose of this study, the authors analyzed the environmental transparency of 412 companies in the energy sector, headquartered in 19 countries, during a four-year period (2016 to 2019).

The data reveal that gender diversity has a positive effect on the environmental transparency of companies in developed countries and on the total model. Furthermore, after removing the US companies, the results remained the same, indicating that companies with more women on the board tend to have greater environmental transparency. Regarding corporate governance variables, the results show that companies that have a corporate social responsibility committee tend to have greater environmental transparency, both in emerging countries and in developed countries.

The findings indicate that if companies aim to have greater environmental transparency, they must encourage female participation on boards, giving them equal opportunities for professional growth. Organizations must deconstruct the ideology that women are fewer valuable members of their boards, which limits their contribution to organizational success. Additionally, regulators can encourage greater female participation on boards through the implementation of quota laws.

The authors’ evidence indicates that the presence of women on board is an antecedent of greater quality in the dissemination of environmental information. Thus, managers of companies in the energy sector must understand that diversity on the board affects communication with its stakeholders through environmental transparency.

Green consumption is fundamental to sustainable development, as it involves adopting practices and technologies that reduce the environmental impact of human activities. This study aims to analyze the influence of consumers’ green orientation on their environmental concerns and green purchase decisions. Furthermore, the study investigates the mediating role of consumers’ environmental concerns in the relationship between pro-sustainable orientation and green purchase decisions.

This study uses a quantitative methodology, applying the partial least squares method to a sample of 927 Portuguese consumers of green products. The sample was collected through an online survey.

Perceived benefits and perceived quality of products play a positive and significant role in influencing green behavior, especially when consumers are endowed with greater environmental concerns. In addition, consumers’ awareness of the prices of green products and their expectations regarding the future benefits of sustainable consumption positively impact green consumption behavior, further intensifying their environmental concerns.

According to the present findings, companies should adopt a holistic and integrated approach to promote green consumption. This means creating premium eco-friendly products, communicating their benefits, addressing the cost factor, emphasizing the future impact of eco-friendly options and raising consumers’ environmental awareness.

It is critical that environmental education is a priority in schools and that there are political incentives for green behaviors. In addition, media campaigns can be an important tool to raise awareness in society.

The results of this study provide important insights for companies on consumer engagement in the circular economy. Deepening knowledge of the antecedents of consumers’ environmental concerns contributes to a deeper understanding of green purchasing decision behavior, allowing companies to support new business strategies.

Fire safety is a pivotal requirement in building codes. Prescribed design criteria have been the norm to achieve it, which imposes limitations on engineers, including the inability to accommodate new solutions/materials. The shift towards performance-based design offers the potential to address shortcomings of the prescribed design. However, this shift also significantly increases the workload on structural engineers without a corresponding increase in their engineering fees. Simplified design tools are needed to assist engineers in this transition.

The paper is divided into sections investigating equivalent standard fire duration, thermal deformations, flexural behaviour and shear capacity of flat slabs when exposed to fire. The first section conducts a parametric study correlating equivalent and realistic fire durations using the average internal temperature profile (AITP) method, resulting in statistical equations estimating equivalent fire duration. The second section evaluates thermal deformations and flexural behaviour through a parametric study considering various parameters. This section results in statistical equations estimating thermal deformations and flexural behaviour of flat slab sections during fire exposure. The final section focuses on shear capacity, developing simplified heat transfer formulas and statistical equations predicting compression zone depth reduction. The section presents methodologies predicting flat slab sections' one-way and two-way shear capacities during fire exposure.

Structural engineers can use the proposed methods for daily design work without applying complex heat transfer calculations. When the equivalent standard fire duration is utilized, a flat slab’s thermal deformations, flexural behaviour and shear capacity under an actual fire condition can be calculated. As such, the methods would be highly beneficial in assessing the structural integrity of a building during an active fire incident.

The paper provides engineers with the tools required to evaluate the safety of flat slab sections during fire exposure. The methodologies presented in the paper enable engineers to use performance-based design for slab sections by (1) converting any real fire scenario to a standard fire with an equivalent duration, (2) assessing their thermal behaviour, (3) evaluating their flexural behaviour and (4) evaluating their flexural and shear capacities. The paper concludes with a case study example demonstrating the detailed application of the developed methods.