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Dielectric composites with low dielectric constants (ε), low dielectric loss (tan δ), and excellent thermal-mechanical stability are highly desired for high signal transmission speed and high device integration. Polytetrafluoroethylene (PTFE) based composites exhibit tremendous potential due to the outstanding dielectric properties and high-frequency stability of PTFE. However, achieving PTFE-based dielectric composites with thermal-mechanical stability and low dielectric constant is challenging. Herein, we develop a glass fiber/polytetrafluoroethylene (GF/PTFE) composite for high-frequency communication applications with a designed skeleton structure. By the paper-making process, the glass fiber can be dispersed in random directions to set up a skeleton with the PTFE matrix entering the space in the fiber network. The modification of GF was also carried out to low down the dielectric loss of the composite. Benefiting from the supporting effect of the skeleton structure and surface modification, the thermal-mechanical stable dielectric composite was achieved with a low dielectric constant, and dielectric loss remained (m-GF content = 15 wt%, ε = 2.326 and tan δ = 5.24 × 10−3 at 30 GHz, xy-CTE = 29 ppm/°C and z-CTE = 47 ppm/°C). Moreover, the composites also have good dielectric constant frequency stability and thermal conductivity. Thus, this work provided an effective way to tailor the structure of functional composites with disordered fiber fillers. [ABSTRACT FROM AUTHOR]

The article highlights that in the space of modern design and artistic and creative education, in particular decorative and applied arts, the importance of paper is growing as both a creative material for modelling and for creating artistic products, and at the same time, the paper is simultaneously one of the most accessible art materials both from the viewpoint of ease of use and cost, and paper craft is an important basis for students' perception and creation of more complex artistic forms of professional art. It is noted that despite various editions, this disparity does not allow fully revealing paper-making as a conceptual whole – in the diversity of its connections with project culture, creative laboratory and design methodology in design. The purpose of the article is to reveal paper-making in the space of decorative and applied arts as well as to identify its theoretical and methodological foundations and to substantiate the role of paper-making in modern design for the formation of students' creative thinking alongside the formation of their artistic and pedagogical skills. These methods were applied and used to reveal the problem: general scientific (analysis, synthesis, generalization, systematization); scientific and specific: historical, artistic, pedagogical, psychological and approaches: systemic-structural, structural-functional, comparative, with the help of which the opinion regarding the phenomenon of paper-making is generalized, its essential content is clarified in the plane of decorative and applied arts, in modern design, and methodical methods are specified principles to the problem regarding the development of creative thinking of students specialized in artistic and pedagogical mastery. In the main content, it is noted that on the basis of methodological provisions and basic principles of traditional craftsmanship, the creative and essential foundations for decorative and applied arts are manifested, which ensures the formation of components of artistic competence and, at the same time, requires the use of students’ creative and figurative thinking. The idea of the key figurative-essential basis for paper-making is provided and it is noted that mastering the specifics of artistic imagery forms students' aesthetic ideas as well as a valuable act of understanding the world. It is highlighted that "paper plastic" also reflects the specificity of the author's approach to the study of compositional, constructive, structural and technological regularities of the work with material. In the content of the Methodological recommendations for conducting practical lessons, it is emphasized that the result should reflect the student's mastery – from the initial sketch through full-scale sketches to the design of the idea in the material. It is justified that in addition to the traditional methodical principles of education, there is a need to use certain art technologies. It is emphasized that the implementation of the developed "Conceptual Technology" in the teaching space of paper-making contributed to the decision-making process regarding the means of creating an artistic image. In the conclusions, it is noted that paper-making as a type of activity occupies an intermediate position between learning and playing and meets the conditions that ensure the effectiveness of the development of creative activity. Learning and practical work in the technique of papier-mâché using papier-mâché is important for the formation and development of abstract, associative, combinatorial, logical thinking, in the process of learning "paper-mâché" the creative thinking of students is formed and the skills of stylization and generalization are acquired, which involves the acquisition of practical experience for figurative reproduction. In the perspective of further research, it is important to consider the need to research, develop and create a model for the development of the future designer’s artistic and creative competence.

Rice straw, a leftover vegetative part of rice plant, is neither efficiently composted nor used as a feed in India. Moreover, due to the need for quick disposal, operational difficulties in small-scale pulp and paper mills and lack of logistical convenience rice straw doesn't find other large-scale commercial applications, and therefore is burnt openly in fields causing tremendous air pollution in parts of India. In the present work, a prospective commercially viable small-scale on-field utilization of rice straw was identified for the first time through an environmentally benign process. Refiner mechanical pulping was successfully used for converting rice straw into paperboard and a food-serving bowl. The prepared rice straw paperboard was found equivalent to grade-III Kraft paper as specified in IS 1397:1990, when compared for tensile and burst index. The molded bowl could become an environment friendly alternative for the presently used disposable food-serving containers made of plastics. Three different chemical treatments were attempted to impart water- and grease-resistance to the rice straw paperboard and bowl as demanded by the conceived application. Water absorption was reduced from 387 to 3 g·m−2 as measured by Cobb60 test and grease-resistance was improved from 0 to 10 as measure by Kit test. Moreover, the sizing process didn't render the bowls harmful to consumers' health in terms of toxicity. Summarily, the utilization of rice straw pulp for making value-added products holds promise in mitigating air pollution, reducing plastic-based disposables, and in promoting entrepreneurship in rural areas. [ABSTRACT FROM AUTHOR]

The widespread use of petroleum-based products has led to increasing environmental and ecological problems, while the extraction and application of various natural cellulose fibers have received increasing attention. This research focuses on the extraction of cellulose fibers from cow dung using different treatments: hot water, hydrogen peroxide (H2O2), sodium hydroxide (NaOH) and potassium hydroxide (KOH) boilings, as well as a selection of the best quality cow dung fibers for papermaking with quality control. The study's objective is to find a sustainable method to extract as much material as possible from renewable biomass feedstock. The results show that the best extraction rate is obtained by KOH boiling with 42% cellulose fibers extracted. Corresponding handmade paper has a burst index of 2.48 KPam2/g, a tear index of 4.83 mNm2/g and a tensile index of 26.72 Nm/g. This project expands the sources of natural cellulose fibers to an eco-friendly and sustainable one and opens up new applications for cow dung. [ABSTRACT FROM AUTHOR]

The widespread use of petroleum-based products has led to increasing environmental and ecological problems, while the extraction and application of various natural cellulose fibers have received increasing attention. This research focuses on the extraction of cellulose fibers from cow dung using different treatments: hot water, hydrogen peroxide (H2O2), sodium hydroxide (NaOH) and potassium hydroxide (KOH) boilings, as well as a selection of the best quality cow dung fibers for papermaking with quality control. The study’s objective is to find a sustainable method to extract as much material as possible from renewable biomass feedstock. The results show that the best extraction rate is obtained by KOH boiling with 42% cellulose fibers extracted. Corresponding handmade paper has a burst index of 2.48 KPam2/g, a tear index of 4.83 mNm2/g and a tensile index of 26.72 Nm/g. This project expands the sources of natural cellulose fibers to an eco-friendly and sustainable one and opens up new applications for cow dung.

Miscanthus is a tall perennial rhizomatous grass with C4 photosynthesis. Because of its high biomass yield, high carbohydrate and low ash content, high calorific value, remarkable environmental adaptability, high water and land use efficiency, and low fertilizer and pesticide requirements, it has become one of the most promising energy crops. Apart from energy uses, it can also be used as raw material for paper-making and for production of a variety of chemicals. Moreover, Miscanthus can also play an important role in environmental remediation and ecological improvement. It has been used to remedy polluted soil, improve the soil quality, and increase the biodiversity by providing habitat for animals and insects. However, its commercialization is still facing great challenge. More study is needed to further decrease its cultivation, harvesting, and processing costs. This editorial discusses opportunities and challenges of Miscanthus as an energy crop and in other applications.

Over 100 million tons of cotton waste are produced annually, representing 35–40% of global textile waste. However, less than 30% of cotton waste is recycled annually. In particular, the fibers less than 7 mm in length dropped during the opening and carding process of cotton waste fabrics have not found a mature utilization method. This work demonstrates and reveals a strategy to transform short cotton fibers into a renewable cellulose fiber self-reinforcing composite paper (CCP). Recycled cotton staple fibers less than 3 mm were prepared into CNFs by TEMPO oxidation. The use of recycled cotton fiber (3–7 mm) as reinforcement and CNFs as a matrix results in a composite material bonded through hydrogen bonding. The recovered cotton fibers and CNFs soliquoid combine together to form a paper pulp, which is then transformed into CCP using wet-laid webs and hot-pressing techniques. When the CNF content reached 5%, the tensile strength of CCP was 86.68 MPa, which is 1.8 times that of the commercial A4 paper. The tensile strength of the CCP only decreases by 25% from the dry state to the wet state, while that of A4 paper after soaking water is almost zero. This makes CCP a special paper with broad application prospects. Since CNF extracted from cotton waste textiles is used as a strengthening agent and without any chemical adhesives added in the paper-making process, which makes the production process of CCP cleaner and can be recycled in a closed loop. Overall, the promising strategy achieves at least four objectives related to cleaner production: maximum recycling of cotton waste, CNF instead of traditional chemical adhesives used in paper-making, water recovery (internal recycling), and realising closed-loop recycling. This technology can potentially be applied to a wide range of colored papers and intelligent packaging papers in the future. [Display omitted] • Cellulose nanofibers extracted from cotton waste were used as an adhesive in papermaking. • A cellulose fiber self-reinforcing composite paper was prepared from cotton waste. • The cellulose composite paper has excellent mechanical strength and water stability. • The cellulose composite paper can be easily recycled with a prolonged life cycle. [ABSTRACT FROM AUTHOR]

In this study, different methods for incorporating mixed or laminar copper microparticles (CuMPs) during papermaking were evaluated to determine the optimum paper-making process and correlate particle concentration and shape with antimicrobial activity. The addition of CuMPs during the disintegration of dry pulp stage was observed to produce a paper with uniformly distributed CuMPs, as determined through optical microscopy and UV–Vis spectroscopy analyses by measuring absorbance spectra in different areas of papers. Determination of two indices related to the concentration and distribution of copper will allow to predict the copper content in other papers. CuMP-paper samples were evaluated for structural, optical, and mechanical strength properties according to paper industry standards. Quantitative analyses by atomic absorption showed that between 24 and 39% of CuMPs were embedded in the paper fibre, independent of particle type. Finally, antibacterial activity analyses were performed according to ISO 20645 and ISO 20743. The results showed that papers with 0.30 g of incorporated CuMPs have antimicrobial activity, independent of particle morphology, with effects observed towards Gram (+) and Gram (−) bacteria and fungus. Furthermore, the evaluation of antimicrobial activity at different times of exposure to the microorganisms showed differences in effects that were dependent on the shape of the CuMPs incorporated into paper, where laminar particles exerted a sufficient effect, while no or a slight effect was observed for mixed CuMPs against Aspergillus niger. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Frogmore Paper Mill is a kind of time machine that allows historians of technology and the senses to study the mechanized paper-making as it was done one hundred years ago. Before the introduction of instrumentation and automatic process control, paper-making depended profoundly on the embodied skills of the workers. This article will focus on thesensory knowledgeandskillsrequired for monitoring and controlling old machinery. Investigating skills-in-use will help to unravel the close link between sensing and acting to keep a continuous production process stable and running. Paper-makers would shift intuitively between different senses and sensory modes of monitoring and diagnosing sensory tell-tales to balance the production process. The importance of sensory knowledge and embodied skills also shaped paper-makers’ self-perception and professional ethos. The article will examine the impact of new process control technology on the crucial role of sensory skills for the paper-makers’ individual and collective identities. [ABSTRACT FROM AUTHOR]

Fibre-laden liquid foams are used in the production process of novel non-woven fibrous materials, employed for example for thermal or acoustic insulation. Here we present an experimental investigation of the stability of such foams. We find that on a time-scale of a few minutes the presence of fibres does not alter the drainage properties of the foam. On a longer time-scale fibres slow down drainage, mainly due to their slowing down of coarsening. The drying of our aged samples leads to a fibre network with a fibre concentration profile that appears to be determined by gravity. Our experiments were performed using fibre concentrations of a few percent, as relevant also to the foam-laid forming of paper, where aqueous foam instead of water is used as a carrier medium for fibres . [ABSTRACT FROM AUTHOR]

Much effort is currently made to develop inexpensive and renewable materials which can replace the polyolefin microporous separators conventionally used in contemporary lithium-ion batteries. In the present work, it is demonstrated that mesoporous Cladophora cellulose (CC) separators constitute very promising alternatives based on their high crystallinity, good thermal stability and straightforward manufacturing. The CC separators, which are fabricated using an undemanding paper-making like process involving vacuum filtration, have a typical thickness of about 35 μm, an average pore size of about 20 nm, a Young's modulus of 5.9 GPa and also exhibit an ionic conductivity of 0.4 mS cm −1 after soaking with 1 M LiPF 6 EC: DEC (1/1, v/v) electrolyte. The CC separators are demonstrated to be thermally stable at 150 °C and electrochemically inert in the potential range between 0 and 5 V vs. Li + /Li. A LiFePO 4 /Li cell containing a CC separator showed good cycling stability with 99.5% discharge capacity retention after 50 cycles at a rate of 0.2 C. These results indicate that the renewable CC separators are well-suited for use in high-performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

But for the phenomenal rise of the Arab civilisation, the earlier Greek scientific traditions could have been lost forever. [ABSTRACT FROM AUTHOR]

Copyright of Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on alkaline paper-making wastewater, a polymer catalyst (FQ) was prepared and characterized by FTIR, ESR and element analysis techniques. The results show that the catalyst has conjugated structure and the conjugate degree increases after heat treatment. The catalyst has quite high photo-catalytic activity, which was verified by the fact that the simulated dyeing wastewater containing methylene blue (MB) or acridine orange (AO) can be degraded completely in 20 minutes under natural light using FQ as the photo-catalyst. Therefore, the synthetic dyeing wastewater can be disposed of using the materials coming from paper-making wastewater. It is a very promising method to treat one kind of wastewater with the materials from another kind of wastewater. [ABSTRACT FROM AUTHOR]

Abstract: The porous carbon electrode in a fuel cell not only acts as an electrolyte and a catalyst support, but also allows the diffusion of hydrogen fuel through its fine porosity and serves as a current-carrying conductor. A suitable carbon paper electrode is developed and possesses the characteristics of high porosity, permeability and strength along with low electrical resistivity so that it can be effectively used in proton-exchange membrane and phosphoric acid fuel cells. The electrode is prepared through a combination of two important techniques, viz., paper-making technology by first forming a porous chopped carbon fibre preform, and composite technology using a thermosetting resin matrix. The study reveals an interdependence of one parameter on another and how judicious choice of the processing conditions are necessary to achieve the desired characteristics. The current–voltage performance of the electrode in a unit fuel cell matches that of a commercially-available material. [Copyright &y& Elsevier]

This is an investigation of the effect of paper-yellowing inhibitors on the rheological, colloidal, and interfacial properties of paper-coating liquids and the associated changes in the liquid surface microstructure. In addition to rheological measurements, we measured the zeta potential and imaged the surface microstructure of coating liquids by transmission electron microscopy (TEM) using an advanced Pt/C replica technique. The zeta potential is related to the concentration of added inhibitors. The images reveal interparticle structuring with increasing concentration of inhibitors. The structuring is related to the interaction between the coating liquids and the inhibitors. It was also found that the viscosity and the elastic modulus increased with inhibitor concentration. The significant changes in mixture properties due to the additives show the importance of the rheological and surface characterization of liquids and the ensuing effect on the corresponding engineering process. [Copyright &y& Elsevier]