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Aerogel composites reinforced by fibers have found extensive applications in the field of thermal insulation and energy conservation. However, the composites are hindered by their high infrared radiation transmittance and weak interface adhesion in practical applications. Herein, we designed and prepared a novel thin composite called 'fiber/whisker/aerogel paper' (SWAP) with a thickness of less than 1 mm. The SWAP integrated SiC nanowhiskers (SiC nw) as opacifiers and ultrafine SiO 2 fibers as reinforcement, fabricated through wet manufacturing and sol-gel process. The 'fiber/aerogel paper' (SAP) and SWAP exhibited low thermal conductivity at room temperature, measuring 0.025 W/(m·K) and 0.033 W/(m·K), respectively. Additionally, they exhibited low densities of 0.195 g/cm3 and 0.225 g/cm3, respectively. Notably, SWAP exhibited excellent high-temperature insulation performance, primarily due to its low infrared transmittance (50% at 3 μm). The incorporation of SiC nw and ultrafine SiO 2 fibers collectively enhanced the interfacial adhesion with the aerogel matrix even amidst rigorous testing (weight loss less than 3%). SWAP also demonstrated flexibility, high thermal stability, hydrophobicity, and flame resistance. Furthermore, a comprehensive investigation into the performance variations and influencing g factors of the material was conducted under different heat treatment conditions. This research provides guidance for the application of such materials under high temperatures. [ABSTRACT FROM AUTHOR]

Bioethanol production using paper wastes seems a promising approach towards sustainable energy, but mainly hindered by hazardous ink. Therefore, in our experimental plan various methods were applied for the deinking of waste newspapers, laser printed papers and examination papers. A newly designed paper pulper reduced the pulping time from 6 h to 2 h. Cellulase (15 FPU/g) from Aspergillus oryzae MDU-4 was found effective for the deinking of newspapers, whereas laccase isozymes (150 U/g) from Ganoderma lucidum MDU-7 along with 2 mM HOBt was preferred for the ink removal and degradation from the examination papers. Ozonation in the presence of Tween-80 was found to be efficient in the removal of toxic toners used in laser printing papers. The biologically and physically deinked papers, studied with the help of SEM, TEM, FTIR, and XRD analysis revealed significant changes in the chemical and surface structure. Moreover, the saccharification of deinked papers with the help of an enzymatic consortium of Trichoderma citrinoviride MDU-1 resulted in 305 mg/g, 377 mg/g, and 409 mg/g release of sugars from the newspaper, examination paper, and laser printed paper, respectively. Finally, the enzymatic hydrolysates fermented with Saccharomyces cerevisiae NCIM-3640 produced 3.35 g/L ethanol, with 40.85% ethanol yield. Image 1 • Pulping time was reduced from 6 h to 2 h by designing a new pulp maker. • Cellulase and laccase were effective for the deinking of NP and EP, respectively. • Ozonation was found appropriate for the removal of toners from PP. • Optimized deinking methods were comparatively better than chemical process. • Ink free paper hydrolysates resulted in 40.85% ethanol yield using S. cerevisiae. [ABSTRACT FROM AUTHOR]

Based on the rapid development of intelligent technologies in recent years, the digital transformation of the whole industry and society has become increasingly important. Among them, digital twins and artificial intelligence have great potentials in improving industry processes and further enhancing productivity. This paper proposes an Intelligent Digital Twin System (IDTS) based on artificial intelligence and digital twins for the paper industry. The system includes the prediction models for the stirring speed of the dump chest, the water consumption of the deflaker, the supply air pressure of the dryer, and the exhaust air temperature of the dryer. The sensors, 5G network slices, and other equipment collect related data during the papermaking process for generating twin data, and we use the prediction models to analyze the data and monitor important indicators (stirring speeds, water consumptions, supply air pressures, and exhaust air temperatures) for the manufacturing processes, which are used to improve the energy utilization and production efficiency of the paper industry and thus facilitate cost saving. We apply this intelligent digital twin system and its associated prediction models to an actual paper manufacturing factory and show their effectiveness by improving the operational efficiency and saving labor and maintenance costs. [ABSTRACT FROM AUTHOR]

Hydrophobic properties belong to the most important factors which determine functional properties of paper products. A number of methods related to the measurement of the interaction between water and paper are already used but most of them give results after specific period of time whereas many unit operations in modern industrial processes (e.g. printing) last usually less than one second. As a result, most of the existing methods are not corresponding to today’s requirements. The aim of the presented research was to develop the method based on image analysis for measuring the dynamics of penetration and permeation of liquid through paper. Special device named eXtended Liquid Penetration Analyser (XLPA) was built for this purpose. Based on the obtained results, the method developed allows to observe and analyse the dynamics of liquid permeation through paper. The proposed method fully replaces the method implemented in the PLG Sizing Tester, which estimated the time of a 50% decrease in brightness of a tested paper sample permeated by ink. Presented method offers the possibility of quantitative measurement of changes in liquid absorption with time resolution of 1/60 s. At the same time, thanks to the use of a camera and image analysis, it is possible to detect local areas of non-homogeneity in paper structure that differ with regards to their capability to absorb liquid, as well as to determine quantitative measures that characterize the non-homogeneity of the permeation process with reference to paper surface. [ABSTRACT FROM AUTHOR]

The gas diffusion substrate (GDS) is essential in the proton exchange membrane fuel cells. Its fabrication techniques affect the performance significantly and are worthy of investigation. In this study, a manufacturing process of the GDS is proposed to understand the formation process of GDS and promote its structure and performance more pertinently. Different states during the preparation process, raw carbon paper, pre-curing, curing, carbonation, and graphitization, are characterized and measured. Experimental and numerical methods are employed to determine the relationships between microstructure, transport, and mechanical performance variation with the fabricating processes. The results show that its porosity, average pore size, and effective diffusivity decrease first and increase after curing. These parameters after graphitization are lower than that of the carbon paper (CP). The electrical resistivity increases dramatically while pre-curing and decreases gradually after curing, carbonation, and graphitization, and it is much reduced after graphitization. Moreover, mechanical measurement results show that both the picks of tensile strength and flexural modulus occur after curing. Its tensile strength shows little change after graphitization compared to the initial paper's. In contrast, the flexural modulus is improved significantly. • Microstructural characteristics of GDS during fabrication are investigated. • Transport properties and pore-scale simulations for GDS are performed. • Precuring, curing, carbonation, and graphitization on properties are studied. [ABSTRACT FROM AUTHOR]

Colored paper is an important industrial paper grade that has applications in various industrial sectors. The increase in coloring efficiency is a key in decreasing the use of dyes, thus can be considered as a "green" process concept; the coloring efficiency depends on the dye retention and dispersion. This work explores the use of nanocellulose, specifically, TEMPO-oxidized cellulose nanofibers (TOCNF), on the coloring efficiency of the preparation of colored paper. Two dyes (i.e. direct blue GL and reactive red 195 (RR195)) were used. Thanks to the large specific surface area and abundant active sites of TOCNF, its use largely improves the direct blue GL retention during the process. The coloring difference (∆E* ab) reached 5.334 with the addition of 13.6 wt% TOCNF and 1.8 wt% direct blue GL in the pulp furnish. The functional group in the dye is a vital factor in determining the dye retention when one chooses TOCNF to enhance the coloring efficiency in the production of colored paper. Furthermore, TOCNF significantly improved the strength properties of both direct blue GL and RR 195 dyed papers. This work demonstrates the potential of nanocellulose in the production of colored paper in improving the coloring efficiency, thus decreasing the environmental impact of the manufacturing process. [Display omitted] • Nanocellulose (i.e. TOCNF) adopted for colored paper preparation • Coloring efficiency improved by TOCNF due to the dye retention improvement • -COO− in TOCNF deteriorating its combination with negatively-charged dye [ABSTRACT FROM AUTHOR]

• Blood glutathione is reagentlessly detected. • Paper-based strips allow to measure 5 μL of sample only. • Blood does not interfere with electrochemical measures. • Filter paper blocks gross impurities from blood. • Electrochemical strips allow for de-centralized tests. Paper-based devices are always more gaining a relevant position in the field of sensors. The continuous demand for affordable, simple, sustainable, and portable devices, is making paper as the ideal basis towards the realization of analytical tools for the easy self-testing. In this work, we demonstrate, for the first time, the development of a disposable paper-based printed electroanalytical strip for reliable, rapid, and high-throughput detection of glutathione in blood. The detection is based on the thiol-disulfide exchange reaction, which produces a detectable compound easily oxidizable at a Prussian Blue/carbon black nanocomposite involving a favorable low-interference overpotential. This nanocomposite is mixed within a carbon-based conductive ink and successively screen-printed onto a wax-patterned filter paper. The employment of paper provides a reagent-free device, as a consequence of the reagents pre-loading within the testing area. After the experimental conditions have been optimized, glutathione has been detected up to 10 mM, with a detection limit of 60 μM, and a sensitivity of (0.102 ± 0.005) μA/mM. This sensor showed satisfactory repeatability (relative standard deviation equal to 10%, for detection of glutathione 1 mM), especially by considering the hand-made manufacturing process. The "real-world" applicability of this strip has been evaluated by quantifying blood glutathione at physiological levels and by recovery studies achieving satisfactory values. [ABSTRACT FROM AUTHOR]

Paper mills are among the most polluting industries, responsible for many organic and inorganic compounds emissions. The fibres electro-kinetic features strongly affect the ability to retain fillers since the fillers–fibres interactions are charge induced. The control and the prediction of these parameters would represent a precious aid for process management, allowing the fillers retention enhancement, a lower environmental impact and the paper sheet properties streamlining. The work presented deals with the implementation and training of four artificial neural networks (ANNs) for the prediction of the main electrochemical and physical features of cellulose pulp and paper. First, two ANNs predict the electrochemical parameters. Following, they were applied to predict the paper sheet properties and fillers retention. The neural models implemented showed outstanding prediction performance, with R2 in the order of 0.999 and a low mean error. The results demonstrate how Artificial Neural Networks may be a valuable instrument for paper mill pollutant reduction. However, they suggest a more inclusive investigation for a better fibres behaviour representation. • Main process parameters of an industrial papermaking process were identified. • Experimental datasets were achieved during industrial production. • Artificial Neural Networks were trained for process parameters prediction. • Accurate predictions of papermaking process were obtained. [ABSTRACT FROM AUTHOR]

Abstract: The flows of paper are analyzed throughout the papermaking processes, with the year 2007 and Korea defined as the system boundaries. In practice, the statistical data on the production, import and export of paper or pulp can be collected with relative ease from the government and industrial associations. However, the input data regarding the volumes of pulp and wastepaper used in different paper products, such as newsprint, printing papers, sanitary and household papers, specialty papers, and corrugating board base, are difficult to obtain because such information is generally kept confidential in the course of corporate operations. The production processes of paper products in Korea are modeled using information on raw materials, their compositions and production yields of products in order to identify and quantify the amounts of pulp and wastepaper used in each paper product. The material flows of paper are then analyzed based on the calculation model derived from the correlation of input and output flows between the individual processes throughout the entire paper lifecycle. Accuracy analysis using both mean absolute error (MAE) and mean absolute percent error (MAPE) is conducted to verify the amounts of pulp and wastepaper calculated from the proposed model against the volumes of domestically consumed pulp and wastepaper provided in the national statistics. Although the calculated values for the past (i.e., the 1980s and 1990s) differ to some degree from the statistical values, the data for the 2000s have a relatively higher level of accuracy, with the MAPE of the total pulp and recycling volume at 5.39% and 5.30%, respectively, thus validating the adequacy of the proposed modeling method. The proposed calculation model can be effectively used in the material flow analysis (MFA) of paper to reduce the burden of data collection and obtain relatively accurate results. [Copyright &y& Elsevier]

The dispute over the paternity of western paper is a longstanding problem. In Italy, a country that has a long tradition of papermaking, many cities compete for the leadership in the production of this material; on the other hand, several studies attribute to Fabriano (13th century), a little center in Marche region, the birth of modern paper and its diffusion throughout Europe. During the 14thcentury, the nearby town of Camerino imposed itself on the paper market, triggering a historic rivalry with the manufacture of Fabriano. As scientific studies on these different productions are missing, a comparative, multidisciplinary investigation has been carried out to characterize a set of thirteenth-fifteenth century handmade papers from Camerino-Fabriano area. Several analytical techniques–some non-invasive such as Fourier-transform infrared spectroscopy (FTIR) and portable magnetic resonance (unilateral NMR), joined to micro-destructive ones such as scanning electron microscopy (SEM), 13C CPMAS NMR spectroscopy, thermo-gravimetric analysis (TGA), sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and reverse-phase liquid chromatography (RP-HPLC)–have been employed in order to study the morphology of the paper documents, to identify the substances used in production process and to define their preservation state. Moreover principal component analysis (PCA) has been applied to the spectroscopic data, allowing the clustering of Fabriano documents with respect to Camerino ones and dividing the samples in two sets. This work improves and confirms knowledges on paper production in Marche region, and the experimental data collected highlight similarities and differences between Camerino and Fabriano manufactures. [ABSTRACT FROM AUTHOR]

This paper describes a cradle-to-gate life cycle assessment of offset paper production in Brazil. The production system is classified into two subsystems: a forest production subsystem, which involves seedling production, soil preparation, seedling planting, forest maintenance, and wood harvesting and transport processes; and an industrial production subsystem, involving wood pulp extraction and bleaching, chemical recovery, and offset paper manufacturing processes. The environmental analysis includes the primary energy demand, environmental impact assessment, and land use indicators. The primary energy demand indicated that the largest amount of both renewable and non-renewable primary energy is consumed by the industrial production subsystem, accounting for 91.0% of the total energy demand. The potential environmental impact assessment included eight impact categories: acidification, ecotoxicity, global warming, human toxicity – cancer effects, human toxicity – non-cancer effects, nutrient enrichment, ozone depletion, and photochemical oxidation. Most of the potential impacts are attributed to the processes of pulp extraction and bleaching, and offset paper manufacturing, mainly due to the production of electricity and thermal energy. As for impacts on land use during the forest activities, a recent developed approach was applied for the regionalized assessment of impacts. Land occupation impacts on erosion resistance, physicochemical filtration, and mechanical filtration showed a reduction in the soil ecological functions, whereas groundwater recharge indicated a credit for the performance of the soil function. With a view to reducing the main life cycle impacts of the industrial production subsystem, an evaluation is made of alternative production scenarios. The best scenario was the substitution of biomass and diesel in the energy generation unit by biomass gasification and optimization of the recovery boiler. [ABSTRACT FROM AUTHOR]

Abstract: 1–2% of global carbon emissions arise in paper production, but the EU plans a 60% cut by 2050. Known process improvements give a 30% cut, but demand may double by 2050: can paper be re-used without recycling by print removal? Three techniques have been developed: abrasion operating in an adhesive wear regime; longer wavelength lasers can ablate toner-print; a solvent can effectively dissolve toner. Energy analysis shows that print removal requires around 10% of the energy required for a new sheet and if this method supplies 80% of future demand, the 2050 carbon target could be achieved. [Copyright &y& Elsevier]

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 the present, there is a big need for materials that can replace materials currently used in technologies, improving mainly the performance and ecological impact of manufacturing. Graphene-based materials are such an alternative, primarily graphene oxide (GO) and reduced graphene oxide (rGO). This work presents a scalable, fast, safe, and eco-friendly method for preparing rGO thin paper (∼5 μm) with conductivity reaching 435 S/m. These rGO papers were fabricated by reducing thin GO paper prepared in an in-house-built vacuum chamber and applying spraying cycles of GO dispersion for a precise and highly controllable deposition process. The atmospheric plasma generated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) plasma source was employed for rapid GO reduction-exfoliation (in the order of seconds) to prepare highly porous rGO paper. Prepared rGO papers were then post-processed by a cold rolling press into uniform conductive self-standing pure rGO papers to create more precisely defined samples and enhance their mechanical and electrical properties. The morphology of GO and rGO papers was studied by SEM and AFM, the chemical changes before/after the plasma reduction were analyzed by the XPS technique and the electrical parameters of the fabricated papers were analyzed by the 4-point probe method and the structure of GO and rGO was analyzed by Raman and XRD methods. The short duration and the scalability potential of the herein-described plasma-reduction-exfoliation method open new possibilities for large-scale implementation of rGO papers in industrial applications. [Display omitted] • Vacuum spraying is a fast method of graphene oxide paper preparation. • DCSBD electrical plasma can trigger fast ∼ 1s reduction of graphene oxide paper. • Rapid reduction leads to significant expansion of the reduced graphene oxide paper. • Sample compression further enhances electrical properties. • The whole production process of GO paper is compatible with in-line production. [ABSTRACT FROM AUTHOR]

Abstract: Paper production is an energy-intensive process and accounted for about 9% of industrial energy demand in Germany in 2008. There have only been slow improvements in energy efficiency in the paper industry over the past twenty years. Policies can accelerate the progress made, but knowledge about the remaining efficiency potentials and their costs is a prerequisite for their success. We assess 17 process technologies to improve energy efficiency in the German pulp and paper industry up to 2035 using a techno-economic approach. These result in a saving potential of 34 TJ/a for fuels and 12 TJ/a for electricity, which equal 21% and 16% of fuel and electricity demand, respectively. The energy savings can be translated into mitigated CO2 emissions of 3 Mt. The larger part of this potential is found to be cost-effective from a firm''s perspective. The most influential technologies are heat recovery in paper mills and the use of innovative paper drying technologies. In conclusion, significant saving potentials are still available, but are limited if we assume that current paper production processes will not change radically. Further savings would be available if the system boundaries of this study were extended to e.g. include cross-cutting technologies. [Copyright &y& Elsevier]

Abstract: The results of assays carried out on plates used in the construction industry, manufactured entirely with solid wastes of a recycled paper plant, are presented and compared with the results obtained using agglomerated wood and plywood plates. Previous results had shown that wastes are composed essentially of polymers when these wastes are generated by recycled paper produced with the “waved type II” shavings. These solid wastes were placed in a mold that was heated and pressed with a hydraulic press in order to obtain the plates. The waste-produced plates were submitted to tests for humidity, swelling, water absorption, density, modulus of rupture-static bending, modulus of elasticity and direct screw withdrawal. These same assays had been carried out on two types of commercial wood plates, agglomerated wood and plywood, in order to compare the results with those obtained with the waste plate. Waste plates had similar behavior to the agglomerated wood plate, but it was possible to distinguish greater flexibility in the waste-produced plate and a significant difference in the tests for swelling and water absorption which showed the waste plate had a better performance than the agglomerated wood and plywood plates. [Copyright &y& Elsevier]

Highlights: [•] Considering the design and manufacturing issues simultaneously is crucial. [•] A combined method integrating FMEA and Taguchi methods has been proposed. [•] A real case of electronic paper display applying the proposed method was shown. [•] The case company has effectively improved the MTBF from 1867 to 4852h. [Copyright &y& Elsevier]

Ex-situ mineral carbonation, a CCU process, is one possible approach for the decarbonisation of emission-intensive industry with hard-to-abate process emissions like the cement industry. The chemical reaction ensures long-term binding of carbon dioxide in minerals with the effect of storing otherwise emitted CO 2 long term. As a major hurdle for CCU processes is often their economic viability, to create incentives for the usage of this process, these carbonated mineral products must become marketable. A separation approach for the reaction products of this process and possible utilization paths are presented. The separation results in three different fractions, each enriched in either the reaction products amorphous silica or magnesium/calcium silicate or unreacted peridotite. The fractions enriched with reaction products are tested as supplementary cementitious material in cement or as a filler in rubber and paper. The application tests show promising results, comparable or even better than the conventional product. Additionally, based on the laboratory explorations, we present initial economic and environmental investigations showing potential carbon footprint reductions of up to 27% for blended cement with a total global reduction potential of 681 Mt CO2e /a. Also, potential carbon footprint reductions of 52% can be achieved by using carbonation products as fillers in rubber and 197% in paper, respectively. While the costs for the utilization of carbonated minerals have been calculated to be higher than for the conventional products, CO 2 emission certificates could ensure the same price for cement and even lower costs for the substitution of fillers in paper and rubber. [Display omitted] • The technical feasibility of the separation of the carbonation products by centrifugal classification has been proven. • Yield of the separation process can be optimized by better liberation of the particles. • Application tests for cement, paper or rubber show the potential of the carbonated and separated products as a (partial) substitute. • The modeled industrial process – in this case a cement plant with carbonation products as clinker substitute – is ecological and economical feasible. [ABSTRACT FROM AUTHOR]

Abstract: Paper is a complex composite material. Its structure and surface greatly influence its end use properties. Calendering is a finishing process applied to paper to provide a shiny surface and to improve the smoothness. Hence, the control of the efficiency of calendering and the characterization of the final product necessitate the measure of the surface modification. Furthermore the relationship between the surface and the obtained level of gloss has to be further developed. The main purpose of this study is to describe the modification of the micro-structure at various scales of the paper surface due to the calendering process (under various processing conditions). The characterization of the paper surface was carried out thanks to an optical device allowing the topographic measurement to be taken at various scales. The equipment combines topographical imaging with a high definition camera, allowing measurement on the exact same area of the sample after each pass in the nip. We therefore introduce a new way to perform multi-scale analysis of the paper surface modification based on fractal theory. [Copyright &y& Elsevier]

Abstract: This paper presents results of an investigation into the potential use of recycling paper mill waste-water to replace mixing water in cement mortar systems for manufacturing concrete masonry products. The physical and mechanical properties of mortar containing various amounts of de-inking waste-water were consequently investigated. A key finding of this study was that replacing mortar mixing water with waste-water significantly improved workability and consistency of cement mortar mixtures. In particular the flow of mortar mixtures increased with increase of waste-water content up to 50% and then levelled off when waste-water content exceeded 50%. Correspondingly, the flow of mortar mix with 100% waste-water replacement at water/cement ratio of 0.50 was found to be equivalent to that of the reference mortar mix with 100% potable water at water/cement ratio of 0.60, indicating potential use of de-inking waste-water as water reducing admixture. The enhanced workability arising from waste-water addition however induced changes in mechanical properties of the hardened material. Compared to reference mortar, replacing 10% and 100% potable water respectively resulted in 19% and 60% reduction of compressive strength, with a corresponding 5% and 16% drop in bulk density, and up to 19% increase in drying shrinkage. Also, water absorption and volume of permeable voids increased with increasing waste-water dosage, albeit marginally. The benefits derived from rheology improvements compared to compromises in mechanical properties due to de-inking waste-water addition strongly indicate clear potential of using de-inking waste-water in production of lightweight cementitious building and masonry elements. [Copyright &y& Elsevier]

• This research proposes a new formulation for the integrated lot-sizing and cutting-stock problem. • It is also presented analytical and numerical comparisons of the proposed model against the model from the literature. • A column generation approach and a relax-and-fix heuristic were applied to solve the proposed model. The integrated lot-sizing and cutting-stock problem has become a trend in the last decades for its applicability and advantage. Consequently, different approaches and formulations have been developed. One of them, which is widespread and related to the production and cutting process of paper, is the research subject of this paper. Fundamental considerations about the literature model are discussed and an alternative formulation is proposed, which consists of a simplified version that can provide better solutions. The upgrade modifications are proved analytically and an instance is analyzed to exemplify the discussed improvement. Moreover, computational tests are performed to compare both formulations. The novelty of the proposed formulation is the possibility of finding better solutions through the reduction of a constraint set, which guarantees the flexibility given by item and object inventories in meeting demand and it also enables a reduction in the total amount of produced paper. The proposed formulation has a significant impact on future research since the addressed model is the target of many scientific researches and practical applications. [ABSTRACT FROM AUTHOR]

The pulp and paper industry traditionally generates large amounts of wastes at different stages of its production process, such as primary sludge that is extremely wet. The aim of this research is to evaluate a new process methodology aiming the incorporation of primary pulp and paper industry sludge waste, still in its liquid state, into cement and lime-based mortars. This procedure was compared with the incorporation of the waste in its dry state, which results from the traditional beneficiation process based on powder drying. Comparison was performed in terms of technological, durability and environmental performance of both wastes (liquid and dry) incorporated mortars, as well as with reference control mortar without incorporation. Two news models of liquid waste processing, for mortars incorporation, called thin and coarse liquid, were developed in order to evaluate technological parameters such as: consistency, entrained air, water retention, mass density, capillary absorption and mechanical strength. These parameters allow the characterization of durability, life cycle assessment and environmental conditions. Technological properties showed satisfactory results in mortars performance when waste was used as a thin liquid with nominal content (optimal mixture) similar to the reference composition. The air content of the mortar was 12% and the water retention 96.8%. In the hardened state, the optimal mixture had a mass density of 1.76 g/cm3, a capillary coefficient of 20.73 g/dm2.min1/2 and mechanical resistance to compression of 3.7 MPa and to flexion of 1.1 MPa, all results meet the limits of the literature for application in construction. It was found that the beneficiation process, which produces the thin liquid is the most efficient for the incorporation of waste into mortars when compared to the dry method. Indeed, the thin liquid waste incorporated mortars showed improved technological, durability and environmental properties. • Development of a new methodology for beneficiation of waste from paper industry. • Two liquid incorporation procedure were evaluated (thin and a coarse liquid). • The thin liquid (TL) presented the best technological and environmental properties. • The thin liquid (TL) can be used in mortars for civil construction. [ABSTRACT FROM AUTHOR]

An enzyme cocktail (xylanase-15U, pectinase-2U, α-amylase-2.5U, protease-2U and lipase- 1.8U) from Bacillus halodurans was applied for the biobleaching of unbleached and ODL (oxygen delignification) agro based pulp in the R&D set up of Shreyans Paper Mills Ludhiana, India, upscaling from 5 g (at lab scale) to 100 g odp (oven dried pulp). Enzyme pre-treatment was carried out at temperature and pH optima of 65 °C and 9–9.5 for 90 min followed by reduced chemical treatment. In case of unbleached agro pulp, as compared to the total chemical bleaching in mill, enzyme cocktail pre-treatment reduced the chemical usage by 50% without compromising brightness and rather with increased tensile strength (23.55%), burst factor (20.3%) and tear factor (3.17%) and reduced kappa number (19.5%). In case of ODL pulp, enzyme cocktail pre-treatment reduced the chemical usage by 40%, yet increasing brightness (2.24%), tensile strength (20.96%), burst factor (5.1%) and tear factor (8.2%) with reduction in kappa number (4.54%). The enzyme cocktail thus can make the paper manufacturing process greener, safer, economical and eco-friendly and may replace big budget ODL technologies. [ABSTRACT FROM AUTHOR]

Abstract: Papermaking has a special place in the cultural heritage of China. Papers made from different types of plant fibers were, and are still used for particular applications. Bamboo paper is a handmade paper that has been traditionally used for book printing and restoration of ancient paper objects since antiquity in China, whereas Xuan paper, the subject of recent previous study, is used for traditional Chinese calligraphy and painting. Following our previous approach on Xuan paper, four modern Bamboo papers manufactured using traditional or chemically-facilitated techniques were artificially aged by UVA radiation and changes to their optical properties were evaluated by reflectance and 3D-fluorescence spectroscopies. Paper samples produced by different methods displayed different fluorescence spectra and UVA photolysis of paper resulted in decreases in the fluorescence intensities and reflectance values, manifested as differing photoyellowing of the papers. Assays of reactive oxygen species, ROS, revealed that papers made by chemically-assisted pulping methods generally produce more hydrogen peroxide or superoxide radicals than those made by traditional methods, which correlates with their relative yellowing rates. Different spatial distributions of calcium and chlorine were also observed by SEM/EDS analysis in the chemically-manufactured papers, probably arising from the specific pulping and/or bleaching chemicals used in their manufacture. [Copyright &y& Elsevier]

• PLA-lined cup released 3.6 times higher microplastics (MPs) than PE-lined cup. • Ethanol separated MPs, additive and cellulose microparticles release from PLA cup. • No cellulose fibres were found on PE cup's lining or hot water contained in the cup. • Lots of cellulose fibres on PLA cup's lining were removed during hot water exposure. • Real MPs level could be higher due to test limits and particles attachments. Polylactic acid (PLA) is a popular replacement for conventional fossil-fuel based plastics products such as polyethylene (PE) due to its high biodegradability and recyclability. Previous studies confirmed that PLA microplastics (MPs) and PE MPs pose similar toxicity risks due to that MPs' risk is primarily attributed to physical and indirect nutritional effects. Surprisingly, despite the widespread use, there have been very few studies of microparticles released from daily products made of biodegradable materials. We investigated release levels from eight single-use paper cups (SUPCs) lined with PLA and PE film. Under typical hot-beverage preparation conditions, the total number of particles released from PLA SUPCs was 4.2 times higher than that from PE SUPCs, with total numbers of 180,000 ± 31,000 and 43,000 ± 10,000 particles per litre, respectively. 22,000 ± 6,000 MPs were released per litre from PLA, which was 3.6 times the level of MPs released from PE SUPCs. In addition, significant levels of cellulose microfibres were released from PLA SUPCs, with quantities of 38,000 ± 31,000 microfibres per litre, while no such fibres were released from PE SUPCs. It should be noted that the levels of these particles may be underestimated due to the exclusion of nanoparticles (less than 0.8 μm, filter's pore size), unidentified microparticles with high fluorescence backgrounds and attachments between different types of particles. In summary, a proportionately higher level of release of additive microparticles together with the release of cellulose microparticles are the key difference between biodegradable plastics like PLA and conventional plastic such as PE. Cellulose blending in manufacturing is likely related to higher MPs release from PLA cups than PE cups. Therefore, it is highly recommended to re-assess the manufacturing process, potential health and environmental risks of biodegradable plastic products as well as the formulation of related policies. [ABSTRACT FROM AUTHOR]

Abstract: The reuse of by-products or waste from industrial processes in construction is an increasingly common practice. In this article, we present an experimental study aimed at evaluating the reuse of paper pulp waste generated in the manufacture of paper for non-structural elements in the form of a plaster–pulp composite material. The analysis of several variables, such as the proportion of pulp added or the mix procedure, in respect to aspects relating to the properties of the fresh and hard material, has demonstrated that it is feasible, although the natural state of the waste material used, with high water content and extensive caking, makes prior treatment advisable. [Copyright &y& Elsevier]

Paper mill sludge (PMS) can be efficiently utilized to produce fuels and chemicals. However, wastewater is usually generated during the de-ashing step of the PMS for fibrous materials recovery. Per process requirements, the wastewater stream must be treated which results in an increase in the overall process production cost. Therefore, this research aims at reusing the wastewater produced during the de-ashing step as a substitute for freshwater addition during the conversion of PMS into ethanol. The advantages of this approach include reducing the amount of wastewater produced and enhancing the overall efficiency of the process. It will contribute to the circular economy of zero waste discharges. The results showed that 30% of the process wastewater can be recycled without affecting the enzymatic hydrolysis and ethanol fermentation. Hence, the amount of wastewater that needs to be treated is reduced by 30% resulting in a cost reduction of 22.5%. The results also showed that wastewater recycling minimized the energy demands in the distillation and evaporation units by 1206 kJ/kg. The energy reduction is due to the increase of metals and total soluble solids in the broth stream after fermentation. This process configuration enhanced the process economy, saved energy and managed waste streams. • Reuse of wastewater in the paper mill sludge conversion. • A certain degree of recycling has no impact on the glucose yield. • Wastewater recycling reduced the energy demand of the process by 1251 kJ/kg metric tons wastewater. • Cost-saving of wastewater treatment by 22.5% when a 30% recycling degree achieved. [ABSTRACT FROM AUTHOR]

In recent years, paper-based microfluidic chips have emerged as a promising microfluidic platform due to their simplicity, low cost, portability, and ease of fabrication. They have been applied in various fields such as biological analysis, environmental monitoring, and medical diagnostics. However, the current paper-based chips made of nitrocellulose membrane still can be improved in liquid flow rate control. To address these issues, a novel paper-based microfluidic chip is designed to control liquid in a wide time range, and the liquid delay and acceleration control are realized by laser cutting and knife crafting respectively. Microfluidic chip's hydrophobic boundaries can be manufactured in a one-step process using laser cutting, taking less than 10 seconds. Additionally, the structural parameters of microgrooves, which have a significant impact on flow rate, can be precisely controlled using a scalpel-based cutting platform. This enables efficient and consistent microgroove processing. Furthermore, experimental optimization of laser cutting and knife crafting parameters is performed, along with an exploration of factors influencing the delay and acceleration effects in the chip structures. The effectiveness of these processing methods is validated through practical applications. In summary, this study realizes a wide time range fluid control in paper-based microfluidic chips, which can achieve delay and acceleration in the range of −55.6% to +828.3%, thus expanding the application range of paper-based microfluidic chips. • A novel paper-based microfluidic chip has been made by simple, cheap, and efficient manufacturing processes. • A stable and efficient method has been developed to fabricate acceleration microgrooves on nitrocellulose membranes. • This chip is able to achieve fluid control with wide time range. • It has potential applications in conducting complex Point-of-care Tests. [ABSTRACT FROM AUTHOR]

Previously, plant-wide disturbance analysis has looked into the propagation of faults through an industrial production process by investigating process measurements. However, the extent of the analysis has mostly been limited to a section of a plant. In this work, we propose a top-down approach which investigates measurements of the complete plant and identifies a section where the disturbance originates. Root cause analysis is carried out thereafter to pinpoint the faulty asset. The proposed approach has three novel elements: Using key performance indicators (KPI) as reference and starting point of the analysis, restricting measurements to a measurement type (e.g. flow) thus focusing on a section and applying the novel method of contribution plots of spectral PCA T 2 statistic to find the contribution of each measurement towards the disturbance observed in the KPI. The approach is described and carried out on a paper machine where a quality KPI showed an established oscillation. [ABSTRACT FROM AUTHOR]

Alkyl ketene dimer (AKD) and vegetable wax (VW) are suitable contenders for supercritical impregnation (SCI) processes, where the waxes may be deposited onto paper fiber surfaces to improve their hydrophobicity for food packaging applications. The solubility of both waxes in supercritical carbon dioxide (scCO 2) with n-heptane cosolvent was measured (40 – 60 oC and 10 – 18 MPa). VW was two orders of magnitude more soluble in scCO 2 compared with AKD, and both sets of data were validated using the Chrastil empirical equation. SCI of AKD wax into paper matrixes was performed at pre-determined solubility conditions, and the resulting hydrophobicity was measured. Results demonstrated that annealing the samples (4 h, 140, 160, 180 oC) immediately following impregnation generally enabled a more rapid development of the CA over a 2-week period. Crucially, using impregnation temperatures and pressures that maximized AKD solubility in scCO 2 resulted in CA up to 130o. Gravimetric analysis of the impregnated samples confirmed the expected deposited wax quantities to within 25% of the solubility quantities. Scanning electron microscopy (SEM) imaging revealed better distribution of AKD in annealed samples and partially confirmed that more intricate structures were responsible for higher measured CA. These results explicitly connect the intuitive relationship that higher solute solubility in scCO 2 should lead to bulk property improvements (i.e. higher CA or hydrophobicity) after SCI. Continued research in this area will enable the development of metrics, linking solubility conditions to desired bulk material properties, and is expected to lead to innovative packaging of green materials and processes. [Display omitted] [ABSTRACT FROM AUTHOR]

Stereolithography 3D printing and digital masks in sequence are used herein to manufacture 3D µPAD in a monolithic layer of paper within 1 s. Multiple experiments were systematically conducted to further understand the fundamentals and limitation of this manufacturing process, and a novel 3D mixer and a fluorescent chemosensor assay used to determine dopamine concentration at high-alkaline pH conditions were successfully demonstrated. Experiment results showed: (1) the 3D mixer is superior than conventional 2D mixer regarding mixing performance and repeatability, (2) dopamine detection and pH indicator can be realized with fewer operation steps and shorter processing time, (3) a truly 3D µPAD, including multilayer microchannels within a monolithic paper substrate, can be created with fewer reagent loss and higher transportation efficiency, (4) a smallest microchannel, 100 µm wide microchannel, can be successfully created on µPAD. These results clearly proved that this proposed 3D µPAD is not only a novel format of µPAD, but it can also simplify the operation steps for an analytical assay while improving the mixing phenomenon via 3D mixer and using minimum sample volume. [Display omitted] • Using SLA 3D printing and multiple digital masks to manufacture monolithic 3D µPAD. • 3D mixer is superior than 2D mixer regarding mixing performance and repeatability. • A truly 3D µPAD can result fewer reagent loss and higher transportation efficiency. • Dopamine detection and pH indicator can be realized with fewer operation steps. • A smallest microchannel, 100 µm wide microchannel, was successfully created. [ABSTRACT FROM AUTHOR]

Miscanthus is an interesting raw material for pulp production, it is a high yield low maintenance plant with a high cellulose and hemicellulose content. Its semichemical pulp can be beneficial in paper for cardboard production process, which nowadays is usually made from secondary fibers, by increasing the mechanical properties of the paper produced. In this study, the influence of the percentage of NaOH used related to the dry Miscanthus weight, digestion time and refining time on some pulp and paper properties have been studied and compared with pulp obtained from commercial fluting paper (CF). Fiber size distribution of the Miscanthus pulp was found to contain a higher fines (less than 0.2mm) percentage than the CF pulp. Hand-sheets made from Miscanthus pulp showed better mechanical properties than the ones made with the CF pulp. CMT, RCT and CCT indexes were higher when using 100% Miscanthus pulp or mixtures of Miscanthus and CF pulp. The only property which worsened was Gurley porosity. Of the three operational variables changed, refining time exerts the most significant influence on the pulp and paper properties measured. [Copyright &y& Elsevier]

Abstract: Five unprocessed historic platinum photographic papers were characterized by a combination of Raman, FTIR and XRF spectroscopies to gain insight into their manufacturing processes and obtain information that can help identify the use of similar papers in works of art in a non-invasive manner. The analysis of one of these papers, ‘Japine Platinotype for Sepia Tones,’ showed a sensitized surface layer in the recto consistent with the use of a parchmentization process of the paper substrate, and that the verso presents a slightly modified surface. Raman and FTIR measurements revealed that this surface layer in Japine is composed mainly of amorphous cellulose. No gelatin or other surface coatings were found to be present in Japine. In the rest of the papers studied, the sensitizer was found to have been applied directly onto the paper fibers and no gelatin or gums were observed as sizings. Relatively larger amounts of mercury were detected in Japine, confirming the use of a Hg salt in a sepia-type platinum paper. The combined use of Raman and XRF provides information that can help discriminate platinum photographic processes involving parchmentization in works of art in a non-invasive manner. [Copyright &y& Elsevier]

[Display omitted] • Humidity sensors based on glycidyl trimethyl ammonium chloride (EPTAC) modified cellulose paper via a facile solution method were fabricated. • The paper is used for the purpose of the humidity sensing material and the sensor substrate. • The as-fabricated paper-based humidity sensor is provided with outstanding humidity sensing properties and good stability. • The humidity sensor was applied to multifunctional applications including human breath rate, non-contact switch and skin humidity. It is of great significance to exploit a simple, cost-effective and environmentally friendly preparation method of multifunctional humidity sensors. However, most humidity sensors need complex manufacturing processes, high cost and narrow usage range. Herein, humidity sensors based on glycidyl trimethyl ammonium chloride (EPTAC) modified cellulose paper via a facile solution method were fabricated, among which the paper is used for the purpose of the humidity sensing material and the sensor substrate. The sensitivity of the obtained sensor was improved by the modification of EPTAC, the response time was decreased to 25 s, which is equivalent to the first-rate paper-based humidity sensors. In addition, the paper-based humidity sensor is provided with well flexibility and biocompatibility, and it exhibits multifunctional applications in respiratory monitoring, non-contact switch and skin humidity monitoring. The low cost and facile preparation technique in this work could provide a useful strategy for developing multifunctional humidity sensor. [ABSTRACT FROM AUTHOR]

To implement solar photocatalytic water detoxification in industrial processes, problems have to be identified. The effluents from paper mills contain non-biodegradable substances like polyphenolic polymer lignin. Photocatalysis is a suitable method to degrade this class of substances. Especially in good solar regions, like Brazil, solar radiation should be ideally used for that process. The German Aerospace Center and the Federal University of Uberlaˆndia-MG, Brazil are cooperating in a project funded by the German International Bureau of the Federal Ministry of Education and Science and CNPq, Brazil to implement solar photocatalysis in the treatment of paper mill effluents. Therefore, the following tasks are worked on: model compounds for the contaminants have been identified and compared to the real effluents. Different photocatalysts and oxidizing agents were tested to shape the degradation process for use in an industrial application. Tests were carried out in lamp reactors as well as in solar reactors to determine the influence of the reactor on the degradation. The kinetic of the degradation was also determined. The test results have shown that the non-biodegradable substances can be very effectively degraded by photocatalytic treatment. Especially in solar reactors like the CPC type reactor, degradation takes place very fast. Total mineralization of the contaminants can be reached. The paper describes the project as well as the test results and will provide an outlook to the implementation of solar photocatalytic detoxification technology in Brazil. [Copyright &y& Elsevier]

[Display omitted] • A reliable diagnostic test presents based on the paper based system. • The three electrode system constructed on paper as platform. • The system shows sensitive behavior for MCF-7 cell in serum samples. Rapid diagnosis of circulating tumor cells (CTC) is of great importance towards patients' treatment. In this work, a simple paper-based sensing platform for label-free detection of circulating tumor cells in the breast cancer cells (MCF-7) is reported. This paper-based aptasensor (P-apt) consists of three-electrode system which constructed based on the manual screen-printed process through a patterned sticker on the paper. To manufacture the MCF-7 sensor, the working electrode of P-apt was functionalized with aptamers that are selective to mucin 1 proteins on the surface of MCF-7 cells. The performance of the prepared P-apt was investigated with cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). The linear range was between 20 and 1×106 cell mL−1, and the detection limit was 7 cell mL−1. Furthermore, the P-apt was able to detect MCF-7 cells in serum samples. The prepared P-apt with simple manufacturing process can potentially be developed to detect various circulating tumor cells. In conclusion, presented P-apt as a low-cost, rapid and robust sensor can be use to detect breast cancer metastases and follow up of metastases treatment. [ABSTRACT FROM AUTHOR]

Abstract: Calendering of paper is an industrial finishing process designed to smoothen its surface so as to improve gloss as well as printability. In this article, we describe how calendering affects paper roughness on both microscopic and macroscopic length scales. We also discuss how these modifications relate to the morphology of the fibers composing the paper sheets. The characterization of the surface is carried out using an optical profilometer and two different species of fibers, as well as their mixture, are used. We first show that calendering induces modifications of the surface on all length scales measured and that these modifications are related by straightforward transformations. We also show that these results hold for papers formed from a mixture of fibers. [Copyright &y& Elsevier]

Abstract: The objective of this research was to develop an alkali pretreatment process prior to anaerobic digestion (AD) of pulp and paper sludge (PPS) to improve the methane productivity. Different concentrations of sodium hydroxide solution were used to pretreat PPS, and then followed by AD of PPS and monosodium glutamate waste liquor (MGWL). Laboratory-scale experiments were carried out in completely mixed bioreactors, 1L capacity with 700mL worked. Optimal amount of sodium hydroxide for organics solubilization in the step of pretreatment was 8g NaOH/100g TSsludge. Under this condition, the PPS flocs structure was well disrupted resulting in the void rate and fiber size decreased after pretreatment, and SCOD increased up to 83% as well as the peak value of VFA concentration attained 1040mgaceticacid/L during AD. The AD efficiency of PPS with and without pretreatment was evaluated. The highest methane yield under optimal pretreatment condition was 0.32m3 CH4/kgVSremoval, 183.5% of the control. The results indicated that alkali/NaOH pretreatment could be an effective method for improving methane yield with PPS. [Copyright &y& Elsevier]

• Bioactive paper production could be adapted to the current papermaking process. • Infrared curing provides the best alternative to produce bioactive paper. • The modified paper by IR curing presents insectifuge and antimicrobial properties. • Antimicrobial activity produces a slight decrease in the biodegradability paper. In this work, the use of infrared radiation as curing media to graft eugenol onto cellulose for bioactive paper obtaining is proposed with the aim to obtain a process compatible with typical processes for papermaking. Eugenol is grafted onto commercial papers using polycarboxylic acid as linking agent using infrared heating for reaction curing. The effect of different operation and design variables, such as power, time, and distance to heat source were analyzed using an experimental design. Optimal infrared curing parameters were determined analyzing reaction degree, mechanical properties and color by response surface methodology. The operation conditions were compared with laboratory, pilot and industrial scale background concluding that the bioactive paper production could be adapted with the current papermaking process doing feasible scaling the bioactive paper production. The modified paper presents insectifuge and antimicrobial properties. A decrease in the biodegradability rate was observed, however, the biodegradable characteristic is conserved. [ABSTRACT FROM AUTHOR]

Abstract: Water removal in paper manufacturing is an energy-intensive process. The dewatering process generally consists of four stages of which the first three stages include mechanical water removal through gravity filtration, vacuum dewatering and wet pressing. In the fourth stage, water is removed thermally, which is the most expensive stage in terms of energy use. In order to analyse water removal during a vacuum dewatering process, a numerical model was created by using a Level-Set method. Various different 2D structures of the paper model were created in MATLAB code with randomly positioned circular fibres with identical orientation. The model considers the influence of the forming fabric which supports the paper sheet during the dewatering process, by using volume forces to represent flow resistance in the momentum equation. The models were used to estimate the dry content of the porous structure for various dwell times. The relation between dry content and dwell time was compared to laboratory data for paper sheets with basis weights of 20 and 50g/m2 exposed to vacuum levels between 20kPa and 60kPa. The comparison showed reasonable results for dewatering and air flow rates. The random positioning of the fibres influences the dewatering rate slightly. In order to achieve more accurate comparisons, the random orientation of the fibres needs to be considered, as well as the deformation and displacement of the fibres during the dewatering process. [Copyright &y& Elsevier]

Abstract: Printing technology, especially inkjet printing, enables mass manufacturing of electronics on various substrate materials. Paper is one potential carrier for printed electronics to realize low-cost, flexible, recyclable smart packages. However, concerns exist regarding commonly used photo paper substrate, in terms of price and reliability against environmental variation. In this work, for the first time, ordinary low-cost and high-moisture-resistance package paper is investigated as an alternative to be the substrate of printed electronics. The surface morphology and electrical performance of inkjet printed interconnections on six different paper substrates from two categories (inkjet paper and package paper) are examined and compared. The printed interconnections on inkjet papers show smaller sheet resistance and better repeatability than those on package papers. However, low-cost package paper stands higher temperature and exhibits better reliability during 85°C/85% RH aging test. Package paper is suitable for smart package applications that have relaxed requirements of conductivity and high requests of moisture resistance. [Copyright &y& Elsevier]

• Programmable microfluidic flow for automatic multistep digital assay. • Wax-paved channels deaccelerate capillary flow. • Enzymatic oxidation process accelerates capillary flow. • Formation of nanozymes in capillary flows. • Equipment-free assay that quantifies analytes by counting the number of colored dots. A single-sheet 3-dimensional paper-based microfluidic analytical device (3D-μPAD) has a user-friendly compact format that eliminates any potential for user alignment error compared to the stacking and folding format. However, achieving sophisticated analysis is still a challenge because forming a complex 3D microfluidic network sufficient for performing analysis in a single sheet of paper is difficult. Here, we present the first report of automatic multistep digital analysis in a single-sheet 3D-μPAD created by controlling the penetration of different wax inks into paper. Simple printing of different wax inks with different spreading properties produces different dimension microchannels in paper. This controllable change in the dimensions of the microchannels results in different flow rates of fluid in each microchannel. Based on the spatial resolution of the microchannels, our strategy enables programming of microfluidic flow through manipulation of the fluidic time delay. This approach creates 3D-μPADs capable of sequential fluid delivery and multistep biochemical reactions with single loading of a sample solution. The methodology can be further expanded to combination with digital assays to measure the concentration of a target analyte by simply counting the number of colored bars at a fixed time. It does not require any external instruments to analyze the measurement of the target analyte concentration. The significance of this work lies in the promising potential for automatic multistep digital assays in a low-cost and easy-to-use paper-based format that can be integrated with a roll-to-roll process for commercial-scale manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the reinforcing effect of recycled newsprint paper (RNP) in cement boards has been investigated. The experimental design consisted of two variable factors namely RNP and calcium chloride (CaCl2). In the sample preparation, boards with density of 0.7kg/m3 were manufactured using fiber/cement ratios of 10:90, 15:85 and 20:80 by weight and 3% and 5% CaCl2 as accelerator. At least four boards (replications) were fabricated for each treatment, and the mechanical and physical properties of the boards were evaluated. The statistical analysis showed that the differences between the mean values of the RNP and CaCl2 contents among each of the groups (treatments) compared were significant. Test results showed that addition of CaCl2 tends to enhance both the mechanical and physical properties of the boards. All properties of the boards were improved when the CaCl2 content was increased from 3% to 5%. The rupture and elasticity moduli of the boards decreased with an increase in the RNP content, and the maximum values were obtained at RNP loading of 10%. The results also showed that as the fiber content was increased, significant increased in water absorption and thickness swelling occurred. Increasing RNP fiber content from 10% to 20% reduced both the mechanical and physical properties considerably. The optimum condition was obtained when the RNP and CaCl2 contents were 10% and 5%, respectively. [Copyright &y& Elsevier]

Abstract: In this work, a technique to enhance the porosity of electro-perforated paper webs using screening matrices is described. The proposed approach relies on the confining effect that acts on a train of sparks when forced to pass through a small hole pierced through a ceramic substrate located in-between two needle-like electrodes. It is shown how the maximum porosity level achievable by the electro-perforation process depends on the drag distance parameter. Since the proposed method is aimed at reducing the latter, an eventual enhancement of the number of perforations per unit area can be obtained. The method has been experimentally tested. It is worth mentioning the suitability of the matrix-aided paper perforation process for its use in industrial environments. [Copyright &y& Elsevier]

Abstract: A physical model of a continuous paper pulp digester is simplified and two subprocesses selected from the digester are modelled by coupled linear partial differential equations. This study focuses on the parameter identification of the simplified linear models. Finite-dimensional approximation of the model is made and a software package developed for identification of distributed parameter processes is applied. This identification system is developed for flexibility to allow identification for different choices of subprocesses and process variables. Unknown parameters of the subprocess models are estimated and the results are illustrated by process simulation and model validation. [Copyright &y& Elsevier]

Solution-phase deposition of nanomaterials represents a highly promising technology with strong industrial application potential for the fabrication of superhydrophobic surfaces. An important barrier towards the adaptation of such materials and processes in a broad range of applications is the limited mechanical durability of the nanostructures. Herein, we present a universal solution to this challenge by benefiting from the unique micro-structure of paper. Our approach is based on transferring the structure of paper into a target material, to form a mechanical protection layer for nanomaterials that were deposited from solution-phase, i.e. spray-coating. We demonstrate this concept through the transfer of the structure of paper to a free-standing PDMS film using a simple molding process. Spraying a dispersion of alkyl-silane functionalized silica nanoparticles on the structured free-standing film results in a hierarchically structured superhydrophobic surface with a water contact angle of 175° ± 2° and a sliding angle <2° ± 1°. The fabricated superhydrophobic surface displays high levels of mechanical, chemical and thermal stability. The robust, inexpensive, scalable, flexible, and environmentally friendly nature of the presented approach may be a key enabler in superhydrophobic coating applications. Unlabelled Image • Transferring the structure of paper as a generalizable strategy for fabrication of robust superhydrophobic surfaces • All-solution processable, inexpensive, scalable, and environmentally friendly fabrication • Inherently flexible coatings adaptable to virtually all types of substrates [ABSTRACT FROM AUTHOR]

A candle filter consisting of a paper stack is an adequate device to clarify the grinding oil employed in the industrial post-processing of hard metal because of its cleaning efficiency and its regenerative capability by means of backwashing. The complex particle deposition mechanisms occurring in this device have not yet been investigated. Filtration experiments with a suitable particle-oil suspension were performed in a pilot filter and in a laboratory filter in order to investigate and model the mechanisms taking place in the process. The effect of operating parameters such as particle concentration and pressure difference on filter performance was evaluated. The results show that more than one filtration mechanism takes place simultaneously. While some depth filtration occurs at the beginning of the lifetime of a candle filter, blocking and cake filtration are the major mechanisms responsible for the filter clogging. Although blocking and cake filtration occur, to some extent, simultaneously, the cake filtration is the mechanism relevant for the modeling and scale-up of the long term filtration process. [ABSTRACT FROM AUTHOR]

The article discusses a critique of paper "Estimate of bacterial and fungal N2O production processes after crop residue input and fertilizer application to an agricultural field by 15 N isotopomer analysis".

• The pricing strategy for wastes and by-products need to be effective. • The logistics costs could hamper the industrial symbiosis network creation. • Stakeholders interests and benefits need to be compromised in an symbiosis network. • Regulations constrain the wastes and by-products exchange among symbiosis partners. • A "facilitating entity" supports the creation of industrial symbiosis linkages. The stakeholders engaged in industrial symbiosis network context expect to optimize resources to obtain a more significant mutual benefit. This paper intends to analyse the value network composed by the stakeholders and the respective flows involved in the symbiosis process. A real case study is developed in the Portuguese pulp and paper sector describing the value network inherent to the fluidized bed sands commercialization; this type of sands is a by-product produced in the fluidized bed biomass boilers used for energy generation located at the pulp and paper plants. The stakeholders, resources, and flows involved in the industrial symbiosis process are identified and the relative importance of value flows exchanged between them is quantified. The results show that the focal organization, sand producers, and end users of material mixtures containing fluidized bed sands are the entities most powerful in the symbiosis network. [ABSTRACT FROM AUTHOR]