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AbstractThe primary heat transfer source in the conventional multi-cylinder drying of paper and board is conduction. Conduction is facilitated by high-tension contact with steam-heated cylinders, while convective drying, the main mass transfer source, operates as heated air flows over the article web in the pockets. This conduction process occurs at elevated temperatures and contact pressures to ensure effective contact between the wet paper web and the heated cylinders. The contact pressures and temperatures of the hot surface significantly influence the conductive drying characteristics. This research paper presents an experimental study that involves designing a simple lab-scale setup with in-situ and continuous sensing capabilities for various commercially available grades of paper and board. Embedded thermocouples measure the temperatures of the heated platen and the sheet, allowing the collection of flux data to determine heat transfer characteristics. The goal of this study is to ascertain the instantaneous contact coefficients for different basis weights as a function of moisture content. The acquired data will provide valuable insights and information toward process development, design, and simulation of the article drying process. [ABSTRACT FROM AUTHOR]

This paper discusses three large, almost identical oval breverls from the eighteenth century burial contexts in present-day Republic of Croatia. Two of them were discovered during archaeological excavations in Žuberak and Prozorje, while the third one from Ližnjan had not been defined as breverl until now. Breverls are the rarest and most enigmatic devotional objects but the three analysed in this paper have a common link other than their appearance. They all contained religious medals from pilgrim sites and papers with the prayer against all evils and demonic attacks on one side and the blessings of saints, the prayer for the identification of those tortured by evil spirits, and the Prologue to John's Gospel on the other. This article compares the papers discovered in them, studies the motifs from the mentioned breverls and analyses other finds from them to provide answers to the questions of their place of production, the identity of the people who wore them and why. Tentative correlation of different bioarchaeological factors, such as age, sex, and health condition of the deceased can give us much information on who breverl bearers were. Apparently, they were the vulnerable members of society, such as pregnant women, people suffering from poor health, or, as prayers from the breverls suggest, individuals believed to be tortured by demons or evil spirits. Taking that into account, breverls were devotional objects believed to provide universal protection, a sort of medicine case for both physical and spiritual problems. [ABSTRACT FROM AUTHOR]

The International Paper Conservation Seminar has now been held as four face-to-face events and four online events. It is a three-day international event delivered in Spanish and Portugese with keynote talks from national and international conservation professionals from Mexico to Chile presenting projects covering works on paper in diverse formats including documents, photographs historic books, and artworks. Countries such as Argentina, Chile, Bolivia, Peru, Ecuador, Mexico, Paraguay, Uruguay, Colombia, Brazil, Spain and Costa Rica have sent delegates to discuss both the social and cultural aspects of conservation work. The seminar is a completely free event for its attendees. It is intended to be suitable for all, with high-level talks addressing issues of management, preservation, conservation, restoration and disaster recovery among many others. From the third event onwards, training workshops for basic treatments have been developed, with the participation of recognized conservation professionals from universities and international institutes, allowing the number of attendees to remain constant since the Covid-19 pandemic. It creates networks and fosters collaboration for professional and institutional projects. The seminars have generated a connected and active community of paper conservators in the region, aware of our limitations, and capable of solving problems collaboratively and according to local resources. [ABSTRACT FROM AUTHOR]

This article asks whether the slow process of divesting Indian native schoolteachers of their traditional authority was only about new concepts and representations of education and knowledge. Following the methodological idea of constellations of affordances, emphasising a relational ontology, the article discusses whether changes in the shape and the relations of objects in Indian classrooms together with the arrival of new objects may have played a silent role in the process of erosion of schoolteachers' authority. Based on a wide range of official and missionary sources, but also referring to individual native voices, the article reconstructs more pervasive and subtle transformations of native elementary classrooms, focusing on surfaces for writing and on "books". The article argues that shifts in the materialities of elementary native schooling took place that repositioned old "gurus" in an unfavourable light before the take-off of teacher training institutions would provide for new definitions of their role as schoolmasters. [ABSTRACT FROM AUTHOR]

La transición hacia el uso del papel para la enseñanza de la escritura en las escuelas elementales públicas en México no fue sencilla. Al finalizar el siglo XIX, se había cuestionado el uso de las pizarras por el riesgo que representaban para la salud, pues muchas veces los estudiantes borraban sus escritos con saliva y el material con el que estaban fabricadas no siempre guardaba las especificaciones necesarias, además el ruido al escribir era insoportable. En cambio, el papel, desde el punto de vista higiénico, pedagógico y estético, fue considerado un material superior frente a la dureza de la pizarra, el brillo de la superficie y la poca precisión que se obtenía en el trazo de las letras. Derivado de este planteamiento, se vislumbró seriamente la posibilidad de la adopción de papel en las escuelas oficiales. Sin embargo, este material era escaso y muy caro. Hacia el cambio de siglo, sólo dos fábricas de papel podían surtir a las escuelas y era necesario que abarataran el precio, que el sistema de distribución garantizara el abastecimiento y que el suministro fuera continuo. Este artículo analiza el inicio del proceso de reconversión de una tecnología para la enseñanza como era la pizarra por el papel. Analizo el gasto que significó y cómo esta modificación fue resultado de una multiplicidad de relaciones sociales, culturales, económicas y políticas que se entrecruzaron para dar una nueva configuración del tiempo, el ruido y los valores establecidos en el salón de clases. The transition to the use of paper in public elementary schools in Mexico was not easy. At the end of the nineteenth century, the use of slates had been questioned due to the health risk they represented since students often erased their writing with saliva and the material with which the slates were made did not always meet the necessary specifications. On the other hand, paper, from a hygienic, pedagogical and aesthetic point of view, was considered a superior material compared to the hardness of the slate, the shine of the surface and the lack of precision obtained in the tracing of the letters. Derived from this approach, the possibility of changing materials in official schools was seriously envisioned. However, the paper represented a very high cost. Only two paper mills could supply the schools and it was necessary to lower the price, and guarantee the supply by enhancing the distribution system. This article analyses the beginning of the conversion process of a technology for learning to write such as the slate for paper. I analyse the expense that it meant for the authorities and families, how the change was the result of a multiplicity of social, cultural, economic and political relations that intersected to give a new configuration of time, noise and established values in the classroom. [ABSTRACT FROM AUTHOR]

For many centuries, paper is the main material for recording cultural achievements all over the world. Infrared (IR) spectroscopy is an essential analytical tool for the structural analysis of paper and pulp chemistry. This review article introduced recent technical and scientific reports in terms of IR spectroscopy in the paper science and application, where interest had increased during the last couple decades (2000–2022). Five parts were described according to the application of IR spectroscopy: the analysis of cellulose and its derivatives, estimation the date of documents, identification the origins of fiber or paper, specification the chemical and physical properties of paper, and characterization the new materials of paper. [ABSTRACT FROM AUTHOR]

The not-so-bygone worlds of music and colonialism in the twentieth century have yielded a wealth of scholarly 'paper knowledge' in the twenty-first of which to build off new archival-musicological work. This article takes a particular archiving direction by turning to paper itself – and pivots the postcolonial pen around the texts and textures of re-engaging colonial history in postcolonial music scholarship. I explore these writing stakes through my adopted narrative of 'the post/colonial music archive', as shaped by paper and paper's sounding elements of tone and voice. Crisscrossing between the colonial moment and the postcolonial pen, I straddle this developing narrative of the archive, and the registers and inflections of extant source narration for what they can jointly vocalize about the music making of the Municipal Brass Band in 1930s treaty port Shanghai, and the Sino-British Club in postwar colonial Hong Kong – two ostensible musical worlds of 'Britain in China' in the twentieth century, here thrown into disarray by the post/colonial archive's own inchoate, counter-tales. Ultimately, in this process, postcolonial music scholarship gains further traction and meaning as a multi-articulating inquiry – and a turn of mind that does not let colonial history and its persistent challenges for writing go askew. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of a hundred and one handwritten essays by master students in Informatics. The students reflected on their experiences of working with pen and paper for reading and writing as a mandatory assignment for the duration of a five-week intensive course. Taking an inductive approach, reflexive thematic analysis was used to identify patterns of meaning across the full dataset. The essays elicited insightful student reflections on learning, knowing, and being. One overarching theme, New connections, and four sub-theses were identified: Handwriting as note making, Being present for learning, Freedom to think, and Materiality of reading and writing. This study contributes to an improved understanding of the affordances of paper and laptops in the lecture room, based on a student-centred approach, and reflects on how student perspectives can be implemented during lectures. [ABSTRACT FROM AUTHOR]

Calcium hydroxide nanoparticles dispersed in ethanol or 2-propanol have been proposed for deacidification treatments of cellulose-based supports and are currently adopted by many paper and paintings conservators. There is however a risk inherent in this treatment: the dispersion would acquire a highly alkaline pH in the presence of moisture, absorbed by the dispersing alcohol solvents or by the cellulose-based support. Consequently, conditions of potential risk would be created for the structural integrity of the cellulosic supports, for some organic film-forming materials and some colouring matter. The simple tests conducted in this study clearly demonstrate that this risk is real, and suggest a cautious attitude in evaluating the suitability of these nano-dispersions for the treatment of some works of art. [ABSTRACT FROM AUTHOR]

Pineapple leaf fibers (PALF) were biopulped using Trametes versicolor, and the resulting biopulp was bleached with xylanase-enzymatic treatments. The biopulping was extensively described using determinations of fiber morphology, color, chemical composition, extractive content, and thermal stability using the structural characteristics determined by XRD and paper properties. The results showed that the chemical and enzymatic treatments shortened the fiber, almost to 50%, and the Kappa index decreased from 27 to 13. Cellulose and holocellulose contents increased from 65% to 74% and from 86% to 91%, respectively, but extractives, lignin (from 12% to 4%), pentosans (from 25% to 14%) and the crystallinity decreased from 58% to 67% in both chemical bleaching and further xylanase-enzymatic processing. Xylanase)enzymatic processing allowed us to obtain whiter (increased lightness color and decreased redness and yellowness tonality) and heavier paper, even though it presented decreased mechanical properties (decreased stress resistance, rupture length, tear resistance and index longitudinal tearing). The xylanase-enzymatic treatment with the best pulping and paper proper)ties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w). [ABSTRACT FROM AUTHOR]

Banana stem is a known alternative to wood for the production of pulp and paper. During the production of paper, it is extremely important to save costs and time while at the same time enhancing quality of produced paper. In the present study, paper was developed from banana stem fiber by optimizing its density. Response surface methodology (RSM) using Box-Behnken design (BBD) was used to determine optimum blending parameters of the developed papers. The influence of banana stem fiber amount (250-1000 g), water amount (1-2liters) and blending time (5-10 min) on paper density was ana)lyzed using software Stat-Ease 360, Version 13. The optimum conditions of banana stem fiber amount, water amount and blending time to achieve a density of 675.75 g/m3 were determined as 461.83 g, 1.31liters, and 8.53 min, respectively. ANOVA results revealed that the quadratic model best fits the density response, with blending time and banana stem fiber amount as the most significant model terms. Linear effects were more predominant than quadratic and interaction effects. The developed density model was in close agreement with experimental findings with an R² value of 0.9748. Developed paper had cellulosic contents, with volatiles as high as 82.11%wb and 2.11% wb ash composition. Future works on thermal properties of paper are encouraged. [ABSTRACT FROM AUTHOR]

Keywords: Elephant Grass; fiber dimensions; non-wood materials; paper; pulping properties; Silk Cotton; ; ; ; ; ; EN Elephant Grass fiber dimensions non-wood materials paper pulping properties Silk Cotton ZH 9782 9790 9 11/21/22 20221220 NES 221220 Introduction Paper materials are diversely used globally for writing, printing, newspapers, books, boxes, wrapping, napkins, toiletries, among others. According to Lwako, Byaruhanga, and Baptist ([23]), non-wood materials such as fibers obtained from Silk Cotton have been anticipated to be suitable for pulp; nevertheless, some of its technological properties (i.e., fiber dimensions and pulping properties) for paper production are unknown. Fibers from the stalk of Elephant Grass (60.03 ± 1.82 µm) and Bagasse (59.85 ± 1.72 µm) would exhibit higher strength properties compared to Silk Cotton (52.24 ± 1.66 µm) and the leaves of Elephant Grass (42.15 ± 1.17 µm) due to their diameters (Table 1). [Extracted from the article]

Water hyacinth (Eichhornia crasspies) was used as a renewable cellulose source to prepare nanofibrillated cellulose (NFC). Due to the porous structure and low lignin content of water hyacinth, a 10 min-treatment time using the high-speed homogenization was sufficient to disintegrate nanofibers. The average width of the NFC treated for 40 min was 16.8 nm. With longer treatment times, a slight decrease in thermal stability of NFC was found while no changes in the crystallinity index of NFC were detected. Moreover, paper was formed from NFC with respect to mechanical treatment times. Results showed NFC treated with longer treatment times could prepare the paper with lower pore sizes between adjacent fibrils and porosity, resulting in higher wettability and mechanical properties. The contact angle of the 40 min-treated NFC paper was 36.0° while this contact angle result could not be measured from the samples of 0 min-treated NFC due to occurrence of large pores between fibers. The tensile strength of the NFC paper with 40 min-treatment time was ~18 times stronger than that of the 0 min-treated NFC paper. Mechanical energy consumption of the high-speed homogenization used to disintegrate NFC was also compared to that of the industrial defibrillation techniques. [ABSTRACT FROM AUTHOR]

This paper presents the results of a series of tests – using a recently-published set of methodological guidelines referred to here as the Protocol – on varnishes traditionally used in the protection and enhancement of graphic artworks. The aim of the research was to study the characteristics of different varnishes when they are applied to a graphic artwork and to analyze their behavior when exposed to conditions that cause alterations, be these natural factors, accidental, or the result of a conservation intervention. Lastly, the study sought to determine whether each varnish was suitable for conservation purposes. Five varnishes were selected for the study: egg white, gum arabic, shellac, rosin, and dammar. Paper test samples were used to study the characteristics of the recently applied varnishes: dimensions, weight, thickness, color, brightness/gloss, pH, surface appearance, drying time, degree of absorption by the substrate, and adhesion to the substrate. The behavior of varnishes was studied via a series of tests that recreated adverse conditions (humidity, light, and temperature). These tested for resistance to ambient humidity, immersion in water, dry-heat aging, and aging in a climate test chamber. After applying the Protocol it was concluded that the varnishes most resistant to different alteration factors are gum arabic and dammar resin. By contrast, shellac and rosin are the most susceptible to alterations, which precludes their use as a conservation material. As well as indicating the varnishes that present the minimum interaction with the substrate and the greatest long-term durability, the results of this research also provide a useful guide to the behavior of these varnishes for their use in preventive conservation. [ABSTRACT FROM AUTHOR]

Within the Master's course "Civil Engineering" at TU Darmstadt, a project has to be carried out. In the winter term 2018/2019 this was the design and fabrication of a bridge spanning 6 m and made entirely from paper. Students had to find bridge types suitable for the use of paper, develop and optimise cross sections and bracing systems and furthermore prove the load bearing capacity. This included the use of experimental methods explicitly. Finally, the bridge had to be erected crossing a small creek. No materials other than paper, cardboard and glue were allowed. [ABSTRACT FROM AUTHOR]

Wrapping paper has an irreplaceable role in the food industry, but the high hydrophilicity of cellulose-based wrapping paper limits its application. Here, we aim to develop a fluorine-free and stable method for preparing the superhydrophobic cellulose-based paper using KH570-modified-n-TiO2 and ε-polylysine (ε-PL) to construct a superhydrophobic surface by layer-by-layer self-assembly. The paper modified by (ε-PL/KH570-modified-n-TiO2)4 multilayers has superhydrophobic and self-cleaning properties after heat treatment. The water contact angle reaches up to 152.8° and the antibacterial rate is close to 100%. The high barrier properties to water vapor better prolong the shelf life of cherries. Therefore, the (ε-PL/KH570-modified-n-TiO2)4 multilayers modified paper can provide a new idea for food preservation. The advantage of the double-layer assembly is that even if the superhydrophobic layer of the wrapper is worn away and lost, the remaining ε-PL is still able to act as a bacterial inhibitor, ensuring that the food is not perishable. [ABSTRACT FROM AUTHOR]

Up to now the literature dealing with the cartography of the former Duchy of Pomerania has assumed that wall map of the region by Eilhardus Lubinus (Eilhard Lubin) had two editions: the first dating from 1618 and the second from 1758. Detailed analysis of correspondence between the mapmaker and his patron, the Pomeranian Duke Philip II, and later letters relating to arguments over payment and paper supplies as well as of a recently discovered copy of the map (now at the University of Szczecin), however, point to the existence of a third edition. This, it is suggested, dates from 1619–1620 and was financed by Lubin himself. Research has also revealed that the paper on which this new exemplar was printed came neither from the Pomeranian dukes' paper mill (as for the 1618 edition) nor from the Unold paper mill in Wolfegg (as for the 1758 edition). [ABSTRACT FROM AUTHOR]

Paper and cardboard elements can be used as a pro-ecological building material. To meet the safety and usage requirements paper elements need to be impregnated, however, most impregnation methods have a negative impact on the environmental performance of the elements. This article describes research that was conducted in order to determine the most effective technique of paperboard impregnation against water and humidity. Particular attention was given to biodegradable coatings, as several oil-based and wax-based wood impregnates were used. The samples were tested for 24 hours in immersion and for 48 hours in high air humidity. Water uptake (measured by the change in mass and thickness), delamination and deformation of samples were monitored. As a result, the basic characteristic of the tested impregnation methods was established – water and water vapour absorption, deformation or delamination after immersion. The lowest water and water vapour absorption was observed in samples impregnated with composed coatings of oils and waxes. [ABSTRACT FROM AUTHOR]