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This study aims to motivate the application of some low-cost minerals in synthesizing nanoparticles as effective additives on the performance of liquid crystal (LC) hydroxypropyl cellulose (HPC) nanocomposite film, in comparison with carbon nanoallotrope.

Metallic nanoparticles of vanadium oxide, montmorillonite (MMT) and bentonite were synthesized and characterized by different techniques (Transmission electron microscopy [TEM], X-ray diffraction [XRD] and Fourier transform infrared [FTIR]). While the XRD, FTIR, non-isothermal analysis thermogravimetric analysis, mechanical analysis, scanning electron microscope and polarizing microscope were techniques used to evaluate the key role of metallic nanoparticles on the performance of HPC-nanocomposite film.

The formation of nanoparticles was evidenced from TEM. The XRD and FTIR measurements of nanocomposite films revealed that incorporating the mineral nanoparticles led to enhance the HPCs crystallinity from 14% to 45%, without chemical change of HPC structure. It is interesting to note that these minerals provide higher improvement in crystallinity than carbon nanomaterials (28%). Moreover, the MMT provided film with superior thermal stability and mechanical properties than pure HPC and HPC containing carbon nanoparticles, where it increased the E_a from 583.6 kJ/mol to 669.3 kJ/mol, tensile strength from 2.25 MPa to 2.8 MPa, Young’s modulus from 119 MPa to 124 MPa. As well as it had a synergistic effect on the LC formation and the birefringence texture of the nanocomposites (chiral nematic).

Hydroxylpropyl cellulose-nanocomposite films were prepared by dissolving the HPC powder in water to prepare 50% concentration, (free or with incorporating 5% synthesized nanoparticles). To obtain films with uniform thickness, the prepared solutions were evenly spread on a glass plate via an applicator, by adjusting the thickness to 0.2 mm, then air dried.

These minerals provide higher improvement in crystallinity than carbon nanomaterials (28%), moreover, the MMT and bentonite provided films with superior thermal stability than pure HPC and HPC containing carbon nanoparticles. The mineral nanoparticles (especially MMT nanoclays) had a synergistic effect on LC formation and the birefringence texture of the nanocomposites (chiral nematic).

This study presents the route to enhance the utilization of claystone available in El-Fayoum Province as the precursor for nanoparticles and production high performance LC nanocomposites.

This study presents the route for the valorization of low-cost mineral-based nanoparticles in enhancing the properties of HPC-film (crystallinity, thermal stability, mechanical strength), in comparison with carbon-based nanoparticles. Moreover, these nanoparticles provided more ordered mesophases and, consequently, good synergetic effect on LCs formation and the birefringence texture of the HPC-films.

This paper aims to study the effect of hydrolysis route of hydroxypropyl cellulose (HPC) on its esterification performance as liquid crystal material. The assessment was carried out from the data of spectra (Fourier-transform infrared analysis [FTIR] and 1H-nuclear magnetic resonance [1H-NMR]), thermal stability as well as optical properties via forming ordered mesophases at lower concentration than HPC.

The HPC was hydrolyzed by hydrochloric acid-methanol at times 9 and 18 h, and the products were esterified by decanoyl chloride. The products of hydrolysis and the esterification were characterized by FTIR, NMR, nonisothermal analysis, thermo-gravimetric analysis (TGA) and polarizing microscope to evaluate the role of degree of substitution of HPC as a result of hydrolysis, on esterification degree, thermal stability and thermal and liquid crystal behavior of the final esterified HPC.

The pretreatment by acid hydrolysis of HPC was successful for synthesizing novel cholesteric hydroxypropyl cellulose ester. The data of FTIR and TGA thermal analysis proved that hydrolysis and esterification of HPC with the decanoyl chain significantly enhanced crystallinity of this cellulose derivative from 0.57 to (1.7–1.9). Moreover, they provided products with superior thermal stability than pure HPC, as noticed from increasing the activation energy of degradation (E_a) from 514.3 to 806.2 kJ/mol. The NMR measurement proved that hydrolysis of HPC for 9 and 18 h decreased the degree of substitution from 3 to 2.1 and 1.3, respectively. Moreover, the esterified HPC showed a promising birefringence texture (chiral nematic) besides decreasing the critical concentration from 30% for HPC to 10% for the esterified unhydrolyzed HPC, while superior decreasing to 1–5% was observed for the esterified hydrolyzed HPC.

There are two stages for preparation of decanoyl ester hydroxypropyl cellulose. At the first stage, HPC was treated by hydrochloric acid-methanol in ratio 1:10 at times 9 and18 h. At the second stage, HPC and hydrolyzed HPC were refluxed with decanoyl chloride (1:6) in presence of nitrogen atmosphere. The final product was precipitated by distilled water.

There are two stages for preparation of decanoyl ester hydroxypropyl cellulose. At the first stage, HPC was treated by hydrochloric acid-methanol in ratio 1:10 at times 9 and18 h. At the second stage, HPC and hydrolyzed HPC were refluxed with decanoyl chloride (1:6) in presence of nitrogen atmosphere. The final product was precipitated by distilled water.

The novelty of this work was focused on enhancing the crystallinity, thermal stability and liquid crystal behavior of esterified HPC, via decreasing the degree of substitution and consequently the type of OH group subjected to esterification. The decanoyl ester formation from the hydrolyzed hydroxypropyl cellulose is able to form ordered mesophases at even low concentration (promising birefringence texture at concentrations 1–5%). It is worthy to notice that the investigated route is able to omit the role of graphene oxide in promoting the liquid crystal behavior of HPC, as it hasn't any effect on critical concentration. This work will promote the use of HPC in technological applications, e.g. high modulus fibers and electronic devices.

This paper aims to investigate the ability of traditional biopolymers, such as funori or the nanoscale form of cellulose nanocrystals, to consolidate fragile paper and preserve it for as long as possible.

Degraded papers dating back two centuries were separated into paper samples for consolidation processes. Funori – a marine spleen – was used as a traditional consolidation material and a mixture with ZnO NPs compared with modern materials, such as cellulose nanocrystals. The samples were aged for 25 years, examinations and analyses were performed using scanning electron microscopy and color change was assessed using the CIELAB system, X-ray diffraction and Fourier-transform infrared spectroscopy.

According to the results, using traditional materials to consolidate damage, such as funori, after aging resulted in glossiness on the surface, a color change and increased water content and oxidation. Furthermore, samples treated with a mixture of ZnO NPs and funori revealed that the mixture improved the sample properties and increased the degree of crystallization. Cellulose nanocrystals improved the surface, filled gaps, formed bridges between the fibers and acted as a protector from aging effects.

This paper highlights the ability of nanomaterials to enhance the properties of materials as additives and treat the paper manuscripts from weaknesses.

This paper focuses on a project to work on the digital library of Arab children's culture for sustainable development (DLACSD).

This project claims to link the past, present, and future by creating a platform that can grow to include not only works by adults but by children who inspire adults with their imagination and the joys they bring to the world.

This project addresses in phases the different aspects of the problem of the lack of material for Egyptian/Arab children at different stages in Arabic on the internet (with copyright law in mind). It is time to fill this gap by having a rich repository of stories, plays, games and songs for children in Arabic in a digital library to enrich the life of the child and to inform the world that much that is worthwhile is available in Arabic for parents, teachers, and children to enjoy.

Through reading samples of the works by Abdel-Tawab Youssef (1928–2015) by using the Dublin Core Elements, it will be informative to see how his writings address the United Nations Goals of Sustainable Development way before these Goals were discussed.

Writers for children, librarians, teachers, psychologists, literary critics, illustrators, and parents need a platform that makes material available to promote children’s culture in the Arab world and to introduce the world to what is of value for children in Arabic.

Currently, communication brings the world together and although the social media and the new technology have introduced problems that are serious, to say the least, collaborators on all levels must play an active role in redressing the social wrongs, especially those affecting children.

This ongoing project by members of a team who believe in interdisciplinarity and multidisciplinarity has taken the first step to create and develop (DLACSD).

This study aims to explore the impact of women empowerment and gender-stereotypical advertising exposure on consumers’ attitudes and purchase intents.

The quantitative research approach was used to assess the women-empowerment and gender-stereotypical advertising on consumers’ attitudes and purchase intentions, explicating the most effective approach in marketing communication in the Arab context, specifically Egypt. Administrated questionnaires were distributed online cross-gender through the use of convenience sampling. The targeted average sample size sought was minimum of 370. Once the data was acquired, partial least square path modelling of structural equation modelling was conducted to test the hypotheses.

Results show that male consumers and female consumers react to a certain extent differently to women-empowerment and gender-stereotypical advertisings. For instance, gender-stereotypical advertisings effect attitude for both genders; it effects male consumers’ purchase intentions, but not female consumers. Women empowerment advertising is insignificant on brand attitude and purchase intention among male consumers; among female consumers, it has significant impact on brand attitude, but not purchase intention. Nevertheless, both categories of advertising contribute to male consumers’ and female consumers’ perception and attitude towards gender role portrayal.

This study provides noteworthy insights and perspectives on women-empowerment (Femvertising) and gender-stereotypical advertising effects on cross-gender consumers in the Arab region (a region of strong masculine culture values). The emerged conclusions aid as a reference and guide for scholars and practitioners to develop effective advertising that create prospect depictions and build inspired female customer base.

The purpose of this study is to conduct a comprehensive and precise investigation into the influence of office environments on employee performance. Office workers spend a considerable amount of time inside a building, and the office environment in which they work has a profound impact on their overall well-being and directly affects their effectiveness and productivity. Yet, the previous studies opted out the importance of hygiene factors like office environment and there is a need to uncover hidden causes and shed light on office environment areas that can be improved.

This research adopts a descriptive research design using a quantitative research method to study the relationships between office environment facilitations and employee performance. The technique of survey questionnaires was employed, and a total of 829 samples were analyzed. Measurement model, structural model and hypothesis testing using PLS-SEM software version 4.1.0.0 were briefly explained.

The study investigated the direct and indirect effects of the office environment on employee communication, interactions, productivity and performance. The findings revealed significant outcomes, indicating that the office environment does indeed have an impact on these employee-based factors. Both communication and interactions, as well as employee productivity as an indirect effect, were found to significantly mediate the connection between the office environment and employee performance.

Insufficient data and analysis exist regarding the factors influencing the effect of employee performance on business. The constraints of time, cost and scope impede comprehensive surveys and thorough analysis. Regrettably, only four specific aspects of the office environment were examined in relation to employee performance, neglecting other significant factors. By acknowledging the potential problems highlighted in this study concerning different office concepts, organizations can endeavor to establish a more conducive working environment. It is imperative to acknowledge that the absence of a well-structured office environment that meets employees’ expectations may lead to unfavorable consequences.

To the best of the authors knowledge, this is the first study of office environment facilitations related to employee behavioral attitude and employee performance in Yangon, Myanmar and this study will help discover new insights of the importance of employee performance in least developing countries.