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Conventional multi-cylinder drying of paper and board involves a mixture of conductive drying from steam-heated dryer cylinders and convective drying by the flow of heated air over the surface of the paper web in the pockets. Pocket ventilation is a critical component in assisting heat and mass transfer during the drying process but is the primary contributor toward removing evaporated water from the web. Air temperature, velocity, and humidity are critical parameters involved in the convective drying process. This paper covers an experimental study involving the design and development of a small lab-scale setup for convective drying of various grades of paper and board, monitoring multiple parameters like paper temperature, moisture content, air humidity, temperature, and velocity measured in situ as the drying proceeds with continuous and accurate sampling capabilities for all parameters in the sample and the system. Instantaneous drying rates, heat, and mass transfer coefficients were also deduced for every time step till the paper completely dried. Furthermore, the coefficients obtained were also reported in the form of dimensionless correlations, and the results were compared against traditional correlations used in the modeling of paper drying. This data will be useful in process development, modeling, design, and the paper drying process simulation. [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]

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]

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]

Electrocoagulation and chemical coagulation are treatment methods based on the same removal mechanism.In this study, it was investigated the effectiveness of coagulation methods using Al electrodes and Al2(SO4)3.18H2O on the wastewaters from cardboard production.In the electrocoagulation experiments, the optimum current and pH where the highest COD removal efficiency by 54% was achieved were determined respectively as 10A and 6.62.The study also it was seen that 58%COD removal was reached for the KCl concentration of 0.5 mg/L that was applied.In the chemical coagulation study, the highest removal efficiencies were obtained as 36%, 95% and 97% for respectively COD, color and turbidity.The results show that higher efficiency could be achieved by electrocoagulation as a pre-treatment step. [ABSTRACT FROM AUTHOR]

The chloropropanols, monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) are potential contaminants that may be found in food contact materials (FCM) from paper and paperboard that have been treated with certain wet-strength resins. They can migrate from the paper matrix to aqueous food and beverages and, due to their potentially carcinogenic properties, are of increasing interest in quality assurance or official controls of paper-based FCM. We hereby describe an improved method for the analysis of 3-MCPD and 1,3-DCP in water extracts of FCM making use of 1-chloro-3-methoxy-2-propanol (CMP) as a novel internal standard. The LOD and LOQ were determined to be 0.4 µg/L and 1.2 µg/L for both analytes, making the method appropriate for the quantification of 3-MCPD and 1,3-DCP below the current legal limits. The method was applied to an extensive market survey of food contact articles made from paper and paperboard including 674 samples. The survey revealed that a high percentage of the products available on the market (e.g., up to 55% of the analysed drinking straws) exceed the BfR limits with values of up to 327 µg/L 3-MCPD and 20 µg/L 1,3-DCP detected in the cold water extract. Remarkable differences were observed concerning the release of 3-MCPD and 1,3-DCP from different kinds of paper-based FCM products, with drinking straws, cupcake cases, bagasse bowls and kitchen rolls showing particularly high rates (>10%) of non-conformity with the legal limits. A number of samples with especially high concentrations were additionally analysed by hot water extraction, which surprisingly yielded considerably lower results for the release of 3-MCPD and 1,3-DCP than cold water extraction. The results indicate that cold water extraction is the most sensitive method to detect the migration and control the risk of exposure to 3-MCPD and 1,3-DCP. [ABSTRACT FROM AUTHOR]

A small box, hitherto described as white lacquerware, currently displayed at the Chinese Pavilion, Drottningholm, Sweden, is an unusual example of artefacts imported from the Far East during the era of the East India Companies. By using microscopy for cross- and thin sections, X−ray fluorescence microscopy, attenuated total reflection Fourier transform infrared spectroscopy, and pyrolysis-gas chromatography-mass spectrometry, some of the specific characteristics of the box are described, and it was possible to differentiate original from more recent restoration material. Among other findings, the results suggest that white glue tempera is a better description, based on indications of calcium carbonate and protein, and support an earlier attribution of the box to an Edo period doll maker in Kyoto. [ABSTRACT FROM AUTHOR]

Phthalates are one of many chemical compounds that are used as plasticisers. Packaging can transfer plasticisers to the surfaces of foods or other materials. A recent study suggested a link between fast food consumption and increased urine phthalate metabolites even though phthalates are most commonly found in food contact materials made of PVC while fast food packaging is most commonly composed of paper and paper board. Phthalates in PVC are usually present in percent concentrations. In non-PVC food contact materials, such as paper or paperboard, the concentrations, if any, are expected to be significantly lower which can greatly impact the analytical method used for their determination. Due to the widespread use of plasticised PVC in many commercial applications, background concentrations of phthalates are a concern for trace concentration analyses and background contamination must be avoided when performing these analyses. A glassware cleaning method was developed and a solvent extraction with dichloromethane and hexane was used to extract phthalates from paper-based food packaging. The extracts were then analysed using a GC-MS/MS. The minimum reporting concentrations for the method were determined to be 0.10–0.40 µg/g depending on the phthalate investigated. Phthalate concentrations in several different non-PVC printed and unprinted packaging are presented. Of the 54 packaging samples tested, 10 samples contained no reportable concentrations of any of the 6 phthalates investigated. Of those that were reportable, all measured lower than 10 µg/g and in fact, most had concentrations less than 1 µg/g. These data demonstrate that phthalates from fast food packaging do not significantly contribute to overall consumer exposure. [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]

Drying of paper during 2000–2018 is reviewed. The review includes new drying processes, multi-cylinder dryers, tissue and impingement drying, TAD-drying, infrared drying and energy use for drying of paper. It includes general aspects of infrared dryers but not drying of coated papers. Paper quality aspects, paper shrinkage and paper isotherms are not included. Impingement drying has been the most successful new technology with several applications while others such as impulse drying has not been commercialized mainly due to problems with paper quality parameters. One promising development is the introduction of steel instead of cast iron cylinders with increased heat transfer reducing the number of cylinders. Future research should focus on modeling the internal transport phenomena and to couple these phenomena to paper shrinkage and quality parameters. The influence of the fabric for the drying process needs more attention, understanding the drying process for new components such as microfibrillar cellulose in the stock and reducing energy use and increasing the amount of renewable energies for drying of paper. [ABSTRACT FROM AUTHOR]

Thermochromic inks, materials that change color at a certain temperature, are increasingly used on papers and other materials in the areas of design, commercials, and security printing. Pseudo-estrogen bisphenol A (BPA) may be one of their main compounds present in mass fractions of up to several percent. In this work, the mass fractions of BPA in thermochromic prints on seven types of paper were determined. Migration of BPA from the surface of the thermochromic print to artificial sweat solutions was investigated as well. Total amount of BPA in papers with thermochromic prints was determined by an HPLC-UV method with ultrasonic-assisted extraction in methanol developed and validated in this work. Total amount of BPA, which ranged from 0.126 to 0.778 mg/g, was compared with the amounts extracted under the same conditions in two artificial human sweat solutions, which differed in chemical composition, ionic strength, and pH-value. Mass fractions of BPA extracted with artificial sweat solutions were from 0.047 to 0.175 mg/g with respect to the mass of the paper. On average, the mass fraction of BPA was four times less when extracted with artificial sweat solutions than the maximal amount extracted with methanol. The amounts of extracted BPA raise a concern of health risk through dermal exposure to BPA from thermochromic prints on paper. [ABSTRACT FROM AUTHOR]

CF4 plasma treatment of a Teflon-like (1,1,1,2 tetrafluoroethane, TFE) chemical spray deposited on paper resulted in an increased level of elemental fluorine on the paper surface. However, TFE molecules undergo bond cleavage and ionization in the presence of the RF-CF4 plasma environment. The abundant fluorine radicals grafted onto the paper surface, via the substitution and opening of the bonds in the cellulose polymers, yielded CFx (x: 1–3) functionalities, as observed by XPS and ATR-FTIR analyses. Lower power (100 W) and treatment times (0.5 min) were sufficient to obtain very highly fluorinated surfaces. The change in the morphology of the surface by the exposure to plasma was complicated because the localized deposition and re-deposition of the plasma-generated molecules on the paper were superimposed on the surface reactions and degradation (etching) at the paper surface. [ABSTRACT FROM AUTHOR]

The current analytical techniques for characterizing printing and graphic arts substrates, particularly those used to date and authenticate provenance, are destructive. This limits the amount of data that can be captured from an individual sample. For samples being evaluated in forensic and archeological investigations, any loss or degradation of the materials is undesirable. Furthermore, it is difficult to produce statistically relevant data for such analytes. We have shown elsewhere that a contactless microwave resonant cavity dielectric spectroscopy technique can discriminate between paper samples made from different plant fiber species based on their lignin content. In this publication, we demonstrate the utility of the contactless resonant cavity dielectric spectroscopy (RCDS) technique in the characterization of naturally and artificially aged paper samples. Based on our experimental results, we suggest that the technique could be used in forensic and archeological investigations of unique paper products. [ABSTRACT FROM AUTHOR]

Variations in wood properties such as basic density, tissue proportion, fibre dimensions and their derived indices, cellulose and lignin content of Melia dubia at five age gradations were examined to evaluate the suitability of the species for pulp and paper production. The study showed that basic density, fibre proportion, fibre length, cell wall thickness, slenderness ratio, solids factor, cellulose and lignin content increased with tree age. However, vessel proportion, fibre width and lumen width decreased. Most of the wood properties were found suitable for making good quality pulp and paper at the age of 4 and 5 years in comparison to other hardwood species among five age gradation. Hence, harvesting at fourth and fifth year of age is suggested in M. dubia for high pulp yield and better paper quality. [ABSTRACT FROM AUTHOR]

To study the life expectancy and difference in aging resistance properties of different modern repair bamboo papers, hydrothermal/dry-heat ageing experiments on repair bamboo paper samples were conducted. The mechanical strength (tensile strength and folding endurance) of different papers during the ageing process were analyzed. Furthermore, the chemical properties (degree of polymerization and pH) of the samples were tested to search for the immanent cause of paper ageing. The results indicated that the ageing resistance ability and durability of modern repair paper are strongly related to their production process, which corresponds with the initial properties of the paper. Mechanical pulp had a low degradation resistance, which was further exacerbated by the chemical bleaching process. In the long run, traditional handmade papers with solar bleaching processes will have longer-term stability and durability. [ABSTRACT FROM AUTHOR]

High-performance air filters composed of a hybrid structure of nanofiber/microfiber were fabricated using wet paper processing. Two types of nanofibers (NF) with average diameters of 180 and 234 nm were mixed with a suspension of microfibers (11.5 and 11.7 µm) in various mixing fractions. Then, the suspension was filtered to fabricate hybridized fiber sheets with a known nanofiber/microfiber composition. The effects of NF diameter and mixing fraction on the performance of the hybrid filters were experimentally investigated. With increasing NF fraction, both the particle collection efficiency and the pressure drop increased. The quality factor (Qf) was used to evaluate the performance of the prepared filters. As predicted by the single fiber filtration theory, the experimentally obtained Qf was almost independent of the mixing fraction of the NF. The collection efficiency and pressure drop of the hybrid filters could be controlled by the NF fraction at the same Qf. Moreover, the inhomogeneity factor of fiber packing (δ) did not significantly affect Qf over the δ range from 3 to 23 for our filters. This implies that the lower particle capturing efficiency due to heterogeneous packing could be compensated by a decrease in the pressure drop, resulting in the same Qf value. Therefore, Qf for particles smaller than 100 nm, which are in the diffusion-controlled regime, can be increased by reducing the NF diameter. Copyright © 2019 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Cellulosic fibres have been obtained by green procedures from the cladodes of Opuntia ficus indica (L.) Mill., constituting a large agro industrial waste in our territory. The materials have been analysed for its relative composition, applying, IR and TG methodologies and it was characterised by the absence of lignin. The fibrous material allowed the manufacture of a handmade paper obtaining an ecological material suitable for packaging purposes. The authors evidenced that the simple protocol based on hot water treatment was able to decrease the amount of hemicellulose in the final material. [ABSTRACT FROM AUTHOR]

Although the quantitative performance of national R&D projects in Korea has increased along with budgetary investments, the qualitative performance of these projects needs improving. In 2014, a new performance evaluation system using qualitative indicators was introduced for national R&D projects, and quantitative performance indicators of evaluated projects were converted into qualitative ones. This paper used quantitative empirical analysis based on the difference-in-difference (DID) technique to examine the relationship between individual projects' performance and the new qualitative evaluation system, to estimate whether the quality of papers and patents increased after the introduction of the new system. The estimation showed that the system had a statistically significant effect on the quality of papers. On the other hand, there was no statistically significant effect on the quality of patents. The results of the paper can inform the future improvement and direction of the new qualitative evaluation system. [ABSTRACT FROM AUTHOR]

In this paper, Multidimensional Cross-Recurrence Quantification Analysis (MdCRQA) is introduced. It is an extension of Multidimensional Recurrence Quantification Analysis (MdRQA), which allows to quantify the (auto-)recurrence properties of a single multidimensional time-series. MdCRQA extends MdRQA to bi-variate cases to allow for the quantification of the co-evolution of two multidimensional time-series. Moreover, it is shown how a Diagonal Cross-Recurrence Profile (DCRP) can be computed from the MdCRQA output that allows to capture time-lagged coupling between two multidimensional time-series. The core concepts of these analyses are described, as well as practical aspects of their application. In the supplementary materials to this paper, implementations of MdCRQA and the DCRP as MatLab- and R-functions are provided. [ABSTRACT FROM AUTHOR]

In this article, we report the convenient preparation of graphene/gold nanoparticle-decorating filter membrane, which could be directly used as electrode for H2O2 sensing. The graphene oxide and chloroauric acid are reduced by L-ascorbic acid before covering the paper substrate. The reduced graphene oxide/gold nanoparticle-paper material is characterized by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The paper composite could be cut into piece and directly used as electrochemical sensor. The electrochemical experimental results show that the paper sensor has satisfying performances in sensing H2O2 with the detection limit of 15 μM and the linear range is 8.53-17.35 mM. This work would propose a novel strategy for the applications of graphene in the fields of electroanalysis and sensing. [ABSTRACT FROM AUTHOR]

Due to increased use of computer-based assessments, comparability studies are moving beyond paper-and-pencil versus computer-based assessments to analyze variances with computers. It is therefore practically important to determine whether screen size and definition of the device affect students' performance. Using data from a large school district giving tests on either Macs with large, high-definition screens or Chromebooks with standard 14-inch screens, this study compared assessment results between devices by grade, subject, and item type. Results showed no significant evidence supporting a large and high-definition screen's positive impact on students' performance. Likewise, there was no relationship between the impact of screen size and grade level as well as item types. Limitations and future studies were discussed. [ABSTRACT FROM AUTHOR]

This paper develops additional advanced operations for transforming maximal planar graphs using the characteristics of both advanced moves due to Pesch et al. and-operation due to Al-Hakim. It shows that the new operations overcome some deficiencies of both the advanced moves and the-operations. The note urges researchers to develop more advanced operations. [ABSTRACT FROM AUTHOR]

Engineering design evaluation is characterized by imprecise (vague) importance and satisfaction levels of criteria, which are better treated as fuzzy variables rather than as subjective crisp variables. Nevertheless, operations on fuzzy numbers tend to increase unnecessarily the imprecision when they are combined for some applications, particularly, when a fuzzy-weighted average (FWA) is calculated. This paper proposes a novel method of operating on fuzzy numbers to obtain a fuzzy-weighted average of desirability levels during design evaluation. The method produces overall desirability levels less imprecise and more realistic than those of the conventional FWA. Furthermore, the balance points of these fuzzy numbers seem to be more credible than those of the FWA. An example is presented, which demonstrates the advantages of the method developed. [ABSTRACT FROM AUTHOR]

The article reviews the exhibition “ Paper Brains” by Andreas Vesalius at the University of Amsterdam.

South Africa is signatory to international protocols that secure migrant rights to healthcare. Its national health policy prohibits discrimination. Pregnant women and children under six years ostensibly enjoy access to free healthcare, irrespective of migration status. What is clear “on paper,” however, becomes considerably more opaque when experienced by those who do not “have papers.” We explore this in Giyani, South Africa, an important migrant destination. Despite a progressive healthcare policy and immigrant rights regime, migrant women’s lack of proper documentation precludes them in practice from accessing state-provided reproductive healthcare. The result is twofold. Women who are entitled to public healthcare prefer to make use of private healthcare, despite the costs, and they make recourse to a range of extra-state relations for healthcare. We focus on one unexpected consequence: that the same healthcare providers who have formally refused access to state institutions may be available to migrants through personal networks, such as in churches. Here, medical care is seen as taking place in a religious register. The difference between what is “on paper” and “what papers migrants have” is critical but may be mediated by access to other realms of the social. [ABSTRACT FROM AUTHOR]

The present study investigates the phenomenon of steam condensation in a rectangle horizontal channel with a mass flux range of 20–70 kg/m2/s and a vapor quality of 0.2–0.8. Mass flux and vapor quality were presented to primarily affect the heat transfer coefficient in shear-dominated flow regime, such as the mass flux is greater than 40 kg/m2/s. At the low mass flux, only slug flow, plug flow, and wave flow were observed. At the high mass flux, the wave flow and annular flow were observed even at the low-vapor quality, and the slug and plug flow were not found during the entire condensation process. Observed flow patterns agreed with Tandon’s flow pattern map. Four kinds of correlations are employed to predict the condensing heat transfer coefficient, and the result reveals that Cavallini’s correlation agrees with the experimental results relatively well. The measured pressure drop has a good agreement with the Lockhart–Martinelli correlation. [ABSTRACT FROM PUBLISHER]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed. [ABSTRACT FROM AUTHOR]

There is current interest in using agro-based biopolymers in industrial applications. Because cottonseed protein is abundantly available, it would be useful to explore its feasibility as a polymeric additive and possible substitute for petroleum-based materials. In this work, we studied cottonseed protein isolate as a paper additive and observed its effects on the paper’s dry and wet strength. The tensile strength of paper was found to vary with the amount of the protein applied. By application of an 11% protein solution to the paper, the dry and wet strength increased by 33 and 16% compared with the paper by itself, respectively. The combined use of cottonseed protein and an acid (acetic, adipic, aspartic, and citric acids) to promote adhesion resulted in even greater dry paper strength but not in greater wet paper strength. Thermogravimetric analysis, infrared spectroscopy, and scanning electron microscopic studies suggested that the protein interacted with acid and that both components interacted with paper fibers to produce increased strength. [ABSTRACT FROM AUTHOR]

Research in restoration and conservation is directed vs. more sustainable working materials, methods and technologies. Electrophoretic removal, from porous material, of undesired stains due to charged species is theoretically an interesting alternative to chemical cleaning methods, but the lack of specific and comprehensive research work leads to controversial opinions about the efficiency and the needed harmfulness for the treated objects. In this work paper, samples with artificial rust stains were subjected to electrophoretic cleaning treatments in mineral water as electrolyte. Treatments were carried out either in a bath by complete sample immersion between the distanced electrodes or by sample wetting and sandwiching between the electrodes. Evaluation of cleaning efficiency and treatment effects was based on colour change measurements (image analysis of scanned paper samples before and after the treatment and by colorimetric data via spectrophotometric measurements), investigation of morphological changes by SEM observations and folding endurance measurements. [ABSTRACT FROM AUTHOR]

A large variety of acid-free Asian and Western papers offer objects conservators numerous applications in their work. Not only have objects conservators borrowed this extraordinary material - paper - from the field of paper conservation but they have also adopted many of the well-developed methods and techniques of handling and manipulating it in their 3-D treatments. Paper meets all material criteria in modern conservation practice, including reversibility, strength, inertness, long-term stability, minimal change in color over time, and compatibility with the original artwork. Additional attractive characteristics are that it is light weight, non-toxic, hydrophilic, it conforms well to surfaces, and is not affected by the solvents typically used. Also, the cost of paper varies but is not excessively high. Finally, having the option of using paper in sheet, fiber or powder form - either in a dry or wet state - allows for even wider applications. This article is a survey of the wide range of applications of paper in objects conservation. Its use can have two very different functions. It can serve as a restoration material, thereby remaining with the artwork after the treatment is complete, and as a tool during treatment, thereby not remaining with the artwork after the treatment is complete. [ABSTRACT FROM AUTHOR]

Many materials machine in either a ductile or brittle manner depending on the cutting conditions. This paper identifies the conditions which allow perspex to be machined in a ductile manner. A quantitative assessment is made of the effects of cutting speed and feed rate on the ductile-brittle transition when turning with a tool having a 30degrees rake angle. [ABSTRACT FROM AUTHOR]

Despite substantial literature on the dyeing of textiles, there is a lack of research about colouring Japanese mending papers (tissue papers) used for paper conservation purposes. This study investigates the fungal bioreceptivity of Japanese tissue papers after they have been treated with various dyes and pigments. A variety of toning materials including plant dyes, watercolours, acrylic paints, inks, pastels, gouaches, and colour pencils are commonly used by conservators for paper toning purposes. In this study, two Japanese tissue papers (Yukyu-shiandSekishu Mare) were treated with selected plant dyes, watercolours, and acrylic paints and then inoculated with fungal species. Quantitative real-time polymerase chain reaction (qPCR) was used to quantify the DNA fromAspergillus nigerandPenicillium rubrumas a proxy for fungal species abundance before and after inoculation and artificial moist heat ageing. qPCR primers which were universal for fungi amplified DNA from papers inoculated withA. nigerandP. rubrumand these species were found to grow less on treatedSekishu MareandYukyu-shipapers compared with untreated papers.Sekishu Marepapers treated with artists' acrylic paints were found to be more resistant to fungal growth than similarly treatedYukyu-shipapers. This study suggests that for the best long-term preservation outcomes for paper materials in archives, libraries, galleries, and museums, acrylic paints generally perform better in conservation terms than most plant dyes and watercolours, although most colourants displayed some bioinhibition. [ABSTRACT FROM AUTHOR]

In this review, we summarize the recent progress in thermal conductivity analysis of nanocellulose materials called cellulose nanopapers, and compare them with polymeric materials, including neat polymers, composites, and traditional paper. It is important to individually measure the in-plane and through-plane heat-conducting properties of two-dimensional planar materials, so steady-state and non-equilibrium methods, in particular the laser spot periodic heating radiation thermometry method, are reviewed. The structural dependency of cellulose nanopaper on thermal conduction is described in terms of the crystallite size effect, fibre orientation, and interfacial thermal resistance between fibres and small pores. The novel applications of cellulose as thermally conductive transparent materials and thermal-guiding materials are also discussed [ABSTRACT FROM AUTHOR]

In Tanzania, tomato (Solanum lycopersicumL) postharvest losses are high due to perishability, lack of awareness and knowledge of postharvest handling techniques, and use of poor packaging materials. Reduction of the current high postharvest losses of tomato can contribute to ensuring food security and improving livelihoods of smallholder producers. Wooden crates serve as a major means of packaging material for transporting tomatoes in most parts of sub-Saharan Africa, including Tanzania. Wooden crates are tightly packed without being properly secured. Crates are often constructed from poor quality timber with rough interiors, resulting in bruising damage to tomatoes during transport. An assessment of how traders perceive postharvest handling practices with wooden crates combined with lining material and how tomato quality losses are affected was carried out in March–April 2014. Use of wooden crates with brown paper lining was more cost-effective at wholesaler and retailer levels. Wholesalers were willing to adopt wooden crates with brown paper lining provided that the net benefits are positive. Wholesalers were overly concerned that retailers would not buy wooden crates with paper lining because they can not visually appraise and evaluate produce through sides of crates for their marketing decisions. This may not necessarily be the case because most retailers buy tomatoes in packed plastic basins. There is a knowledge gap between wholesalers and retailers on acceptance of appropriate packaging materials. Proposed interventions that tend to maximize net benefits of the supply chain actors could reduce postharvest losses and make produce more available and affordable to consumers. [ABSTRACT FROM AUTHOR]

When dealing with contemporary art, conservators have to address not only the material aspects of the artwork but also other highly complex issues. The Argentinian artist Leon Ferrari is a representative example. He created avant-garde art installations but also worked with traditional techniques. His works raise dilemmas over concepts such as authorship, authenticity, legitimacy of art. Some of his artworks only interested him as a means to express his opinions and he was not concerned about alterations in their appearance. Therefore, what should be kept in them is not in an area of certainty for conservators. An essential key for achieving a responsible and respectful conservation result, is to understand the ideology involved in each ‘art piece’ created by Ferrari. [ABSTRACT FROM AUTHOR]

A 2014 exhibition of Meriç Algün Ringborg at Moderna Museet, Stockholm, Sweden, exploring identity and belonging involved the making of facsimiles. The installation included a sound work, booklets to be taken, and a book to be read. Exhibition copies were created of personal letters for open display which were not to be touched. Contrary to the artist's wishes, the work was constantly handled. Made for this one installation, the facsimiles transcended the exhibition and were returned with the work to the artist. The paper examines issues of authenticity and control from a conservation standpoint, and details discussions surrounding reproduction in contemporary art museum conservation practice. [ABSTRACT FROM AUTHOR]

The implementation of chemical filtration in air-conditioning systems in archive and library repositories has become standard practice for heritage institutions in many countries. This practice is codified in official standards with general reference to a substantial body of scientific publications on the effects of air pollutants on paper materials. In this paper we report the application of a well-established decision analysis approach elaborating an integral cost-benefit perspective to provide decision support to four European national heritage institutions confronted with dilemmas in connection to chemical air filtration. Available scientific evidence for air pollution induced damage of paper material is reviewed and weighed against financial and environmental costs of air pollution control. Exposure of paper to both indoor and outdoor generated air pollutants at typical concentration levels observed within storage areas is expected to cause minimal to no additional yellowing and embrittlement, while the costs of chemical air filtration are significant. From a cost-benefit perspective the use of chemical air filtration in typical library and archive repositories is therefore discouraged. [ABSTRACT FROM AUTHOR]

This study focuses on the changes in properties of cellulose-based paper, which can take place as a consequence of its contamination by dust particles. The PM1 (fine) and PM10 (coarse) fractions of the dust particles from archival repositories were collected on cellulose filters Whatman 41, polytetrafluorethylene, and quartz filters. The latter two types of samples were subsequently analyzed gravimetrically, with ion chromatography, PIXE, and the thermal–optical transmission method, giving mass, ionic, elemental carbon, and organic carbon concentrations. After artificial aging, the viscosity-average degree of polymerization of cellulose (DPv) was measured. It was confirmed that cellulose-based paper can undergo substantial changes when contaminated by dust particles and artificially aged. The decrease of the DPvof cellulose showed a negative correlation with the deposited mass of sulfate ions in the dust particles. Considering the particle size fraction, the results suggest the decisive importance of the fine (PM1) particles. The results provide better understanding of how particulate matter contributes to the chemical degradation of cellulose-based paper. Such knowledge is of importance when considering appropriate conservation measures in archives, libraries, and galleries. [ABSTRACT FROM AUTHOR]