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Paper is a material that is used in many areas of everyday life. The development of paper with special and environmentally friendly properties will contribute to it being used differently than before. In this work, we present a simple, fluorine-free and low-cost method to prepare a multifunctional paper coating with TiO2 nanoparticles modified with 3-aminopropyltriethoxysilane (KH550) and polydimethylsiloxane (PDMS). The effects of the content of precursors such as titanium isopropoxide (TTIP) and PDMS on the wettability, microstructure and durability of the coating were investigated. The result showed that the coated paper exhibited excellent superhydrophobicity and self-cleaning properties with a water contact angle (WCA) of 162.7° and a water sliding angle (WSA) of 2.5°. In addition, the coated paper showed excellent oil/water separation with over 98% after 10 test cycles and high mechanical resistance with an abrasion resistance of 0.26% weight loss after 20 abrasion cycles using the Taber abrasion test (ASTM D4060) with wheel type CS-10. The results of this study indicate a possible method for producing fluorine-free multifunctional paper, which has the potential to expand the application versatility of the material. [ABSTRACT FROM AUTHOR]

A comparative study of the supramolecular structure, physicochemical properties, and morphology of the powder celluloses (PCs) obtained from the waste paper of newsprint and cardboard, plant celluloses, and nonconventional raw materials was conducted using the methods of FT-IR spectroscopy, high-resolution solid-state 13C NMR spectroscopy, wide-angle X-ray scattering, and scanning electron microscopy (SEM). According to the FT-IR and 13C NMR spectroscopy results, the functional composition of the PCs is similar to that of the wood PCs and matches highly purified cellulose samples. The crystallographic structure of the powder samples corresponds to the structure of cellulose I. The crystallinity and the transverse dimensions of the crystallites are 39.4 and 40.2%, and 45 Å [110] and 54 Å [110], for the PCs from newsprint paper and cardboard, respectively. These values considerably exceed those for the initial waste paper samples. A comparative analysis of the SEM results showed a significant similarity among the PC fibers of different origin. The results of the study of the physicochemical properties of the PCs isolated from the waste paper allow predicting their competitive application in comparison with plant PCs. [ABSTRACT FROM AUTHOR]

Stone paper is a relatively sustainable alternative to traditional fibre-based paper. Stone paper is made using resin such as high-density polyethylene (HDPE) and a mineral such calcium carbonate (CaCO3). Plasticizers, bulking agents, coupling reagents, dispersing agents, and inorganic fillers are added in the stone paper formulation for imparting different properties. However, the HDPE, used in stone paper formulation, is not biodegradable and can be replaced with biodegradable polymers to make stone paper more environment friendly. The biodegradable stone paper can be easily made using relatively cheaper blown film process. The stone paper can also be made from CaCO3 waste of traditional paper industry and recycled polymer waste. This review paper provides overview about the stone paper, the biodegradable polymeric materials which can be used instead of HDPE, information about the converting processes for stone paper; it's applications and comparison to the traditional paper. [ABSTRACT FROM AUTHOR]

Traditionally, cellulose nanofiber (CNF) production has primarily relied on virgin cellulose sources. Yet, the shift to using paper mill sludge (PMS) as a source for CNF underscores the significance of reusing and recycling industrial byproducts. PMS contains significant amounts of cellulose that can be extracted as a raw material. The purpose of present study is to provide a sustainable approach to PMS utilization as a paper coating additive in the cellulose nanofibrils (CNFPMS) form via simply scalable wire-wound rod coating method. The effect of CNFPMS additive amounts at two coating layers on microstructure and surface properties of coatings such as porosity, air permeability surface roughness and optical properties such as brightness, gloss and CIE L*a*b* is studied, which they can also provide insight for the eventual print performance. Results indicated that the obtained CNFPMS in paper coating shows 52% decrease in porosity, presenting significant improvement in the coating microstructure. The marginal increase in permeability coefficient and surface roughness, 54% and 10%, respectively, suggests improving color reproduction and preventing color density losses. Optical analysis showed slight decrease in brightness and gloss, as was expected. Notably, the lightness was improved, which also indicates increasing color gamut volume in printing applications. As a result, the current work offers a sustainable approach to manage PMS for use in paper coatings as a high-value-added material. [ABSTRACT FROM AUTHOR]

Paper-based sensors have good application prospects due to their flexibility and environmental protection. However, paper-based materials are difficult to balance both conductivity and flexibility. This paper mainly reports a high porosity conductive paper based on bamboo wood mixed fiber materials through the wet-manufacture method. The crucial material properties, and long-chain structure of PEDOT:PSS, play an important role in conductivity and flexibility. The relevant experiments show that conductive paper has excellent physical properties and electrical signal transmission capacity. Among them, the conductivity of paper-based electrodes is up to 18.52 S/cm, and there is a low delay in the transmission of the electric signal, when the signal frequency is 300 kHz, the phase frequency angle changes by only 4.9°, not only that, as an electrode, the human pulse signal measured in the capacitive sensor is normal. Under the action of other composite materials, the manufactured electronic paper has a certain mechanical strength, and the thickness is about 90 μm, lower than ordinary paper products. The research shows that the paper-based electrode has the advantages of high conductivity, low hysteresis, light, and thinness, which provides the possibility to be used as a flexible electrode. [ABSTRACT FROM AUTHOR]

Sustainable and low-cost old corrugated container (OCC) paper has been extensively employed in packaging materials for shipping and handling different products to substitute petroleum-based plastics. However, the poor mechanical strength and wet stability of OCC papers impede their general use. To solve these problems, we proposed constructing a dense carboxymethyl cellulose (CMC)-Mn+ (Mn+: Ca2+, Al3+) crosslinked network in the OCC papers' interior, allowing outstanding mechanical performance and waterproof. The resulting OCC-CMC-Al3+ paper demonstrated a superior tensile strength of 49.6 MPa and Young's modulus of 1.9 GPa, substantially higher than that of original OCC paper (tensile strength of 15 MPa, Young's modulus of 0.7 GPa) and comparable to commercial plastics. More significantly, the OCC-CMC-Al3+ paper demonstrated a superior wet strength of 13.0 MPa to the original OCC paper of 0.6 MPa. Additionally, the OCC-CMC-Al3+ paper exhibited excellent thermal stability, durability, and biodegradability. Generally, the biodegradable, strong, and water-resistant OCC-CMC-Al3+ paper is a potential and ecofriendly material for substituting nonbiodegradable plastics. [ABSTRACT FROM AUTHOR]

Plant-fibre ancient-books with cultural significance should be protected from moisture and pollution. In this work, a strategy of surface in-situ protection (building composite coating) was adopted to achieve good hydrophobicity, moisture-proofness and ink-contamination resistance at the surface of archaistic paper. By pre-ring opening of epoxy-based poly(vinyl silsesquioxane) (POSS) and spray of POSS/polyvinylidene fluoride (PVDF) mixed solution, in-situ construction of POSS/PVDF composite coating at the surface of ancient paper was achieved. Compared to water-absorbing ancient paper, POSS/PVDF co-modified ancient paper shows strong humidity resistance. The surface of co-modified ancient paper (epoxy-group pre-ring opening for 45 min) displays high hydrophobicity (water contact angle of ~142.6°), ascribed to greatly improved surface roughness of paper fibres as well as complete coverage of high-content Si/F elements on fibre surface. POSS-modified and neat ancient-paper materials show surface water contact angles of ~113.9° and 0°, respectively. Robust ink-resistance of POSS/PVDF co-modified ancient-paper surface is realized. The innovation in this work lies in perfect synergy of cage-shaped POSS and threadlike PVDF in coating. This work might open a way for surface nondestructive-protection to ancient-books for damp-proof, hydrophobic and anti-fouling characteristics. [ABSTRACT FROM AUTHOR]

The pulp and paper industry is critical to global industrial and economic development. Recently, India's pulp and paper industries have been facing severe competitive challenges. The challenges have impaired the environmental performance and resulted in the closure of several operations. Assessment and prediction of the performance of the Indian pulp and paper industry using various parameters is a critical task for researchers. This study proposes a framework for performance assessment and prediction based on Data Envelopment Analysis (DEA), Artificial Neural Networks, and Deep Learning (DL) to assist industry administration and decision-making. We presented a case study based on eight industries to demonstrate the methodology's applicability. This study analyses and predicts industry performance based on sample data observations over 30 years. The result suggests the DEA-DL-based efficiency prediction has an overall MSE of 0.08 compared with the actual efficiency. Furthermore, the efficiency rankings are compared between the three techniques. The results suggest that the integrated DEA-DL method is primarily accurate in most scenarios with the actual values. The findings of this study provide a comprehensive analysis of environmental performance for policymakers. [ABSTRACT FROM AUTHOR]

Trimethylsilyl cellulose (TMSC) was employed as the coating matrix for the application of zinc oxide nanoparticles (ZnO) onto paper surfaces and the protections of ZnO/TMSC coating against UV-induced damages and fungal spoilage were evaluated. Filter papers were immersed in 2% w/v TMSC solution loaded with ZnO and air-dried. Three ZnO/TMSC suspensions were prepared with 0.1, 0.5, and 1% w/v ZnO NPs. The presences of ZnO/TMSC protective layers were confirmed with ATR-IR spectroscopy. The coated papers exhibited high surface hydrophobicities. After the coated papers were subject to 365-nm UV irradiation at 400 W for 3 h, the contact angles dramatically dropped. The trimethylsilyl (TMS) groups exposed on the surface formed a moisture barrier and were partially removed on UV exposure. ATR-IR revealed that more TMS groups were removed in the protective layer with no ZnO. UV-irradiated papers turned yellow and papers protected with 1% ZnO/TMSC exhibited significantly lower color changes than that of the uncoated one. Compared to the TMSC-coated paper, the addition of ZnO resulted in a significant reduction in tensile strength at maximum. However, after UV irradiation, significant increases in both the strain at break and strength at maximum were only observed in 1% ZnO/TMSC-protected papers. Regarding their anti-fungal properties, the 1% ZnO/TMSC films were effective in growth inhibitions of Aspergillus sp. and Penicillium sp. on the nonirradiated papers. Despite being hydrophilic after UV-irradiation, growths of the molds were severely suppressed on the UV-irradiated paper. [ABSTRACT FROM AUTHOR]

The production of paper is a key component for global civilization. Around 300 million tonnes of paper are produced every day globally, with matured pulpwood being the major contributor. Due to rising demand for paper and the depletion of available wood resources, researchers are now focused on finding alternative non-wood resources that are suitable for pulp and paper production. The current study aims to produce eco-friendly and biodegradable paper using a combination of Eichhornia crassipes (water hyacinth) and dried flowers. Water hyacinth is considered as a lignocellulose plant which contains 57% lignocellulose, and dried flower contains 40% cellulose, which is the prime source for paper production. Various sections of water hyacinth, including wet and dry petiole, leaves, and root, were blended with dried flowers through the soda process. Then, the physical properties and FTIR analysis was carried out to identify the quality of the paper produced. The paper produced from root and dried petiole has a lower thickness (1.0 mm and 0.5 mm) than other mix proportions. The opacity of the leaves was found to be 0.5% (light passing) and for the root 0.7% (light passing). Also, the dry petiole and root paper have a good dry tensile strength of 1.30Kpa and 1.20Kpa, respectively. Hence, paper made from dry petiole and root was found to be efficient and suitable for the paper industry. [ABSTRACT FROM AUTHOR]

Persistence and misuse of antibiotics eventually give rise to the progression of resistance development in bacteria. Consequently, accurate, fast and cost-effective sensing devices are required to govern the presence of drugs. Herein, we design a microfluidic paper-based device (μPAD) for the detection of Rifampicin. We selected this analyte because of its persistent overuse for the treatment of tuberculosis, among the major causes of death around the world. In this work, we have integrated Fe-reinforced ZnS nanoparticles supported with rifampicin (RIF) imprinted material on the exterior of Whatman filter paper for the fabrication of paper-based microfluidic device (μPAD). In this fabricated μPAD colorimetric detection was performed, and the synergistic effect of Fe and ZnS was recorded as compared to individual nanomaterials. A distinct color indicator was used to quantify the concentration of the targeted substance by the naked eye. The fabricated paper-based sensor possessed high sensitivity for rifampicin detection, recorded linear calibration curve representing 0.1 µM LOD and excellent selectivity, in comparison to other inferring agents present in real samples. The practical application of this designed μPAD was validated by applying a real sample. [ABSTRACT FROM AUTHOR]

As China's demand for paper products increases, China's paper industry faces enormous pressure to reduce greenhouse gas emissions. By using material flow analysis in combination with input–output analysis, this study measured the waste paper recovery rate in a more accurate method and analyzed the impact of waste paper recycling on the carbon emissions from China's paper industry. China's waste paper recovery rate estimated in this study was close to 70% in 2017, much higher than that of 48% obtained with the traditional method. The regression results displayed a negative relationship between waste paper recovery rate and CO2 emissions per unit of paper consumption during 2000–2017 in China. The rolling regression results further indicated that the impact of waste paper recycling was becoming stronger on reducing CO2 emissions per unit of paper consumption in China. Since an inverted "U" shape relationship exists between waste paper recovery rate and its reduction effect on carbon emissions from the paper industry, the regression results suggested that China's waste paper recovery rate has not reached the optimal level with regard to carbon emissions from China's paper industry. Thus, although China's waste paper recovery rate has reached a relatively high level, currently waste paper recycling is still an effective method to reduce carbon emissions from China's paper industry. [ABSTRACT FROM AUTHOR]

Some ancient Chinese paper artifacts dyed with amur cork tree bark extracts are currently preserved to different extents in museums and libraries worldwide. As traditional natural plant dyes, the long-term performance of the amur cork tree bark extract-dyed handmade paper has been questioned under a preserved environment. The photodegradation process of the extract-dyed papers was examined under accelerating artificial UVA irradiation conditions according to China national standard-paper and board- accelerated aging (exposure to light). Changes during aging were analyzed by optical observation and scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR), pH, and tensile strength and folding endurance tests. The results showed that the main components from extracted dyes played an important role in affecting the photodegradation properties of dyed paper. The changes in surface color, pH, morphology and mechanical properties after the artificial UVA accelerated degradation tests revealed that a suitable concentration of the extract dyes for maintaining the long-term irradiation stability of the paper is important. [ABSTRACT FROM AUTHOR]

Improving paper characteristics through natural and cost-effective fillers is a massive issue in the paper industry. In the process of manufacturing paper, inorganic and organic fillers are utilized. Organic fillers are only appropriate for specific applications, and their expensive cost has limited their use. Here, various concentrations of sugarcane press mud (SPM) waste were applied to obtain pure calcium oxide nanoparticles (CaONPs) after the calcination to use as a potential filler in the papermaking by mixing the CaONPs at various ratios (5, 10, 15, and 20%), and paper properties have been investigated. Transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning electron microscope (SEM), and energy-dispersive X-ray spectroscopy (EDX) were utilized to characterize the CaONPs produced. The finding reveals that the influence of nano CaO fillers filled at different ratios (5, 10, 15, and 20%) on tensile, tear index, porosity, and smoothness was slowly decreased when increasing the content of nano filler to 35.9, 55.0, 565.7, and 260.3 at (0%) decrease to 30.7, 42.4, 381.6, and 188.4 at (20%), respectively. Also, opacity and brightness were increased from 93.0 and 71.7 at (0%) to 99.0 and 72.3 at (20%), respectively. The previous results revealed that the CaONPs at (20%) represent the optimal owing to the small particle size of CaONPs is satisfactory for provoking the prosperities of paper. [ABSTRACT FROM AUTHOR]

Sensitizers are used to prepare photosensitive materials for ink-printing and thermal-recording media. Typical sensitizers contain an aromatic ring and exhibit aryl hydrocarbon receptor-mediated activity. They can accumulate in aquatic biota, leading to the disruption of ecosystems. Effluent from paper recycling plants has been identified as a source of contamination, and the presence of sensitizers in toilet paper may represent a new source of contamination in aquatic environments. To examine possible sources of contamination by sensitizers, this study investigated the levels of sensitizers in recycled toilet paper. We also studied the prevalence of sensitizers in rivers receiving effluents from sewage treatment plants in Japan, from 2020 to 2022. We detected eight sensitizers and related compounds in both toilet paper and river water samples; their total concentrations ranged from 0.78 to 34 µg/g (mean: 12 µg/g) in toilet paper and 58–1167 µg/L (median: 77 µg/L) in water. In the water samples, sensitizers were partitioned between liquid and suspended solid phases, and in suspended solids, sensitizers accounted for an average of 42% of the total. Correlation analysis showed a high correlation between sensitizer composition in the water from a river receiving sewage treatment plant effluents and toilet paper. Since these compounds were also detected in the river water analyzed in this study, toilet paper should be considered a novel source of sensitizers contamination in sewage treatment systems. [ABSTRACT FROM AUTHOR]

Holocellulose fibers provide great potential to make paper with high performance. However, inappropriate reaction conditions may limit its improvement in paper performance due to the lack of sufficient research data. In this work, paper is prepared from the birch holocellulose fibers based on peracetic acid treatment and the papermaking process. The features of resulting holocellulose fibers are evaluated for different peracetic acid treatment conditions such as temperature and time. It reveals that high temperature and long treatment time lead to the degradation of hemicellulose/cellulose and the destruction of fibers, which further results in the poor mechanical performance of paper. By optimization for the treatment condition of holocellulose fibers, the corresponding paper exhibits the highest tensile strength (93 MPa), good bursting strength (601 kPa), and tearing strength (647 mN). The determination of optimum conditions will provide guidelines for the industrial production of holocellulose fibers and paper. [ABSTRACT FROM AUTHOR]

Highlights: m-BN/PNF nanocomposite paper with nacre-mimetic layered structures prepared via sol–gel film transformation approach presents excellent thermal conductivity, incredible electrical insulation, outstanding mechanical property and thermal stability. When the mass fraction of m-BN is 50 wt%, m-BN/PNF nanocomposite paper exhibits excellent thermal conductivity and electrical insulation. The λ∥ and λ⊥ are 9.68 and 0.84 W m−1 K−1, and the volume resistivity and breakdown strength are as high as 2.3 × 1015 Ω cm and 324.2 kV mm−1, respectively. The m-BN/PNF nanocomposite paper with 50 wt% m-BN also presents outstanding mechanical properties (tensile strength of 193.6 MPa) and thermal stability (thermal decomposition temperature of 640 °C). With the rapid development of 5G information technology, thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent. In this work, "high-temperature solid-phase & diazonium salt decomposition" method is carried out to prepare benzidine-functionalized boron nitride (m-BN). Subsequently, m-BN/poly(p-phenylene benzobisoxazole) nanofiber (PNF) nanocomposite paper with nacre-mimetic layered structures is prepared via sol–gel film transformation approach. The obtained m-BN/PNF nanocomposite paper with 50 wt% m-BN presents excellent thermal conductivity, incredible electrical insulation, outstanding mechanical properties and thermal stability, due to the construction of extensive hydrogen bonds and π–π interactions between m-BN and PNF, and stable nacre-mimetic layered structures. Its λ∥ and λ⊥ are 9.68 and 0.84 W m−1 K−1, and the volume resistivity and breakdown strength are as high as 2.3 × 1015 Ω cm and 324.2 kV mm−1, respectively. Besides, it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640 °C, showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment. [ABSTRACT FROM AUTHOR]

Traditional papermaking was a significant innovation that intrigued the information-sharing society in a wide range of the globe. The importance of finding the historical background hidden behind the historical traditional paper is critical to understanding societies in history. Advanced molecular biological research is applied to many forensic studies to identify the origin and criminal events. Yet, biological research refrained from the heritage science of traditional papers due to its damage to the samples. The current study explores the Pearson correlation between DNA in traditional paper and non-destructive measurement of characteristics of traditional paper. DNA concentration and purity were found to have a proportional relationship based on the CIEL*a*b* color system. The color of the traditional paper was assessed assessment shows green and yellow rather than red and blue. The DNA concentration demonstrated a positive linear correlation with the peaks of 992 cm−1, 1599 cm−1, and 1628 to 1638 cm−1 region, which were lignin-specific functional groups. The presence of lignin in traditional paper defines the colors green and yellow, which is related to the presence of a cell wall. The quantity of cell walls present is linked to DNA survival during the traditional papermaking process. Furthermore, the partial least square (PLS) regression model is established. The prediction model based on DNA, paper properties, and smoothing + the second derivative preprocessed attenuated total reflection-Fourier-transform infrared (ATR-FTIR) spectral data demonstrated valid purity predictions. The evaluation parameter of the cross-validated prediction model contains a low Root Mean Square Error of Cross-Validation (RMSECV) of 0.091 for DNA purity. The determination coefficient was close to 1. However, the further establishment of a validated DNA extraction methodology is required for the consistency of the prediction model for DNA concentration. The hierarchical clustering analysis demonstrated the agglomerative dendrogram on traditional paper samples. For the dendrogram, the Nasu paper mulberry (originating in northern Japan) was distinguished from another paper mulberry (originating in southwestern Japan) by clustering. By multivariate statistical analysis, the DNA presence and quality were predictable from the Japanese traditional papers. In addition, the clustering analysis provided the possible origin of paper mulberry materials for traditional papers. Based on the preliminary information, the need for DNA analysis on historical traditional paper can be determined. [ABSTRACT FROM AUTHOR]

The economic development of a country directly depends upon industries. But this economic development should not be at the cost of our natural environment. A substantial amount of water is spent during paper production, creating water scarcity and generating wastewater. Therefore, the Pollution Control Board classifies this industry into red category. Water is used in different papermaking stages such as debarking, pulping or bleaching, washing, and finishing. The wastewater thus generated contains lignin and xenobiotic compounds such as resin acids, chlorinated lignin, phenols, furans, dioxins, chlorophenols, adsorbable organic halogens (AOX), extractable organic halogens (EOCs), polychlorinated biphenyls, plasticizers, and polychlorinated dibenzodioxins. Nowadays, several microorganisms are used in the detoxification of these hazardous effluents. Researchers have found that microbial degradation is the most promising treatment method to remove high biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater. Microorganisms also remove AOX toxicity, chlorinated compounds, suspended solids, color, lignin, derivatives, etc. from the pulp and paper mill effluents. But in the current scenario, mill effluents are known to deteriorate the environment and therefore it is highly desirable to deploy advanced technologies for effluent treatment. This review summarizes the eco-friendly advanced treatment technologies for effluents generated from pulp and paper mills. [ABSTRACT FROM AUTHOR]

With the popularity of air fryer, there is an increasing demand for air frying paper. Here, we successfully prepared an air frying paper with good barrier capacity, cytocompatibility and degradability by coating chitosan, zein and lignin containing cellulose nanofibers (LCNFs), in sequence. The obtained triple-coated paper has a high kit number of 12 and a low Cobb 60 value of 4.93 g/m2. Importantly, it had excellent hot oil resistance, which was no penetration even at oil temperature of 210 °C. The triple-coated paper also showed good resistance to ethanol, acid and alkali solutions. These excellent barrier capacities were due to the smooth and dense barrier layer formed by chitosan, zein and LCNFs. Thus, the triple-coated paper was successfully used in the air fryer to fry fries and chicken drumsticks. And the good cytocompatibility and degradability of the coated paper further promote its practical application. [ABSTRACT FROM AUTHOR]

Honesty of publications is fundamental in science. Unfortunately, science has an increasing fake paper problem with multiple cases having surfaced in recent years, even in renowned journals. There are companies, the so-called paper mills, which professionally fake research data and papers. However, there is no easy way to systematically identify these papers. Here, we show that scanning for exchanged authors in resubmissions is a simple approach to detect potential fake papers. We investigated 2056 withdrawn or rejected submissions to Naunyn–Schmiedeberg's Archives of Pharmacology (NSAP), 952 of which were subsequently published in other journals. In six cases, the stated authors of the final publications differed by more than two thirds from those named in the submission to NSAP. In four cases, they differed completely. Our results reveal that paper mills take advantage of the fact that journals are unaware of submissions to other journals. Consequently, papers can be submitted multiple times (even simultaneously), and authors can be replaced if they withdraw from their purchased authorship. We suggest that publishers collaborate with each other by sharing titles, authors, and abstracts of their submissions. Doing so would allow the detection of suspicious changes in the authorship of submitted and already published papers. Independently of such collaboration across publishers, every scientific journal can make an important contribution to the integrity of the scientific record by analyzing its own pool of withdrawn and rejected papers versus published papers according to the simple algorithm proposed in the present paper. [ABSTRACT FROM AUTHOR]

Soot stain from diverse sources is the most common stain that stains historical paper documents found in libraries, museums, and storage facilities. It is believed to be one of the types of deterioration that arises from the contact between stains and paper sheets. Therefore, in the present work, the effectiveness of the synthesized hybrid nanogel consisting of carbopol and nanoparticles (NPs) of ZnO, TiO2, or Fe3O4, in low and high-viscosity forms, for eliminating soot stains from historical paper manuscripts was conducted. The prepared hybrid nanogels were characterized utilizing the TEM, AFM, XRD, DLS, and Zeta Potential techniques. Following preparation, the soot-stained paper samples were heated to 105 °C for 6 days, a process known as accelerated thermal aging. Surface morphology, mechanical properties and the color change of the paper samples were investigated. The prepared hybrid nanogel had a spherical shape with well-defined edges and uniform size, with an average particle diameter ranging from 30 to 35 nm. There was no significant NPs agglomeration seen, suggesting uniform dispersion in the carbopol matrix. Additionally, the prepared gels' crystal structure and phase purity were revealed by the XRD analysis results. Paper fibers were visible in some parts of the treated sample with TiO2/carbopol hybrid nanogel at high-viscosity before aging. Cleaning soot-stained paper samples using high-viscosity Fe3O4/carbopol hybrid nanogel is more successful than using low-viscosity nanogel. the sample treated with high-viscosity ZnONPs/carbopol hybrid nanogel produced the highest total color differences (ΔE) (26.17). The paper sample treated with high-viscosity ZnO/carbopol hybrid nanogel exhibited the maximum tensile strength (61.8 N/mm2) and elongation at break (1.174%). The evaluation of the paper samples both before and after the cleaning process revealed that, the treatment with high-viscosity ZnO/carbopol hybrid nanogel gave the best results in removing soot stains from stained paper samples. [ABSTRACT FROM AUTHOR]

Nowadays, a high percentage (> 50%) of the paper produced in Europe uses recovered paper (secondary fibers) as raw material. In order to improve the mechanical properties of the paper produced, different kinds of additives are usually incorporated into the paper. Emerging renewable materials based on agricultural or forest residues, such as cellulose nanomaterials, have recently proved good capacities as reinforcing agents for different applications. In this work, pulp from wheat straw with a content of cellulose nanomaterial has been produced and tested as a mechanical reinforcing agent for paper production. A soda semi-chemical process was applied for the delignification of straw, to produce pulp with high cellulose content. Posteriorly, pulps with cellulose nanofibers were obtained in a high-pressure homogenizer, applying three different pretreatments to the cellulose pulp (acid hydrolysis, enzymatic hydrolysis and thermal treatment with glycerol) in order to facilitate the obtention of cellulose nanomaterial. Handsheets of paper were prepared from two sources of secondary fiber (fluting paper and old corrugated containers), adding different percentages of wheat straw derivatives (0, 3.5, 5 and 7%). The fibers' morphology and the papers' mechanical properties were investigated. Noticeable improvement rates (up to 25%) were observed for some mechanical properties of paper containing nanocellulose produced after the enzymatic and acid pretreatments. The quality of the secondary fibers source also affected the improvement rates achieved, with higher percentage changes for the lower-quality recycled paper. [ABSTRACT FROM AUTHOR]

In this paper, three kinds of micro-nano bamboo powder (MBP) and alkyl ketene dimer (AKD) were added to the polyvinyl alcohol/cellulose nanofiber (PVA/CNF) coating to prepare PVA/CNF/MBP coated paper and PVA/CNF/M-MBP/AKD coated paper. The results showed that MBP improved the oleophobicity of PVA/CNF coating, and the grease resistance grade of PVA/CNF/B-MBP and PVA/CNF/M-MBP coated papers reached the highest level, with a kit number of 12. Among the PVA/CNF/MBP coated papers, the PVA/CNF/M-MBP coated paper has the best hydrophobic properties, with the water contact angle and Cobb value of 74° and 21.3 g/m2, respectively. In addition, when the AKD dosage was 0.2% in the PVA/CNF/M-MBP/AKD coating, the kit number of the coated paper was 11, the Cobb value was 15.2 g/m2, the water contact angle was 103°, and the tensile strength was found to increase slightly. Therefore, compared with PVA/CNF coated paper, PVA/CNF/M-MBP/AKD coated paper has good strength and excellent hydrophobic and oleophobic properties. [ABSTRACT FROM AUTHOR]

A turn-on fluorescent aptasensor based on a paper-based microfluidic chip was developed to detect arsenite via aptamer competition strategy and smartphone imaging. The chip was prepared by wax-printing hydrophilic channels on filter paper. It is portable, low-cost, and environmentally friendly. Double-stranded DNA consisting of aptamer and fluorescence-labeled complementary strands was immobilized on the reaction zone of the paper chip. Due to the specific strong binding between aptamer and arsenite, the fluorescent complementary strand was squeezed out and driven by capillary force to the detection area of the paper chip, so that the fluorescent signal arose in the detection area under the excitation wavelength of 488 nm. Arsenite can be quantified by using smartphone imaging and RGB image analysis. Under the optimal conditions, the paper-based microfluidic aptasensor exhibited excellent linear response over a wide range of 1 to 1000 nM, with a detection limit as low as 0.96 nM (3σ). [ABSTRACT FROM AUTHOR]

Paper recommendation with personalized methods helps researchers to track the latest academic trends and master cutting-edge academic trends efficiently. Meanwhile, the methods of previous paper recommendation suffer from three problems: data sparsity of content-based and collaborative filtering methods; Graph-based recommendations do not fully consider the personalized information of authors and their articles; Cold start based on deep learning. To overcome those difficulties, we propose a personalized paper recommendation method based on a knowledge graph and Transformer encoder (KGTE) with a self-attention mechanism. Firstly, we add auxiliary information (article title, publication year, citation times, and abstract) as attributes to the nodes of knowledge graph(KG), which contain author, digital object unique identifier(DOI) and keywords. Secondly, BERT is used to represent the semantic information features of the article and Transformer is introduced to fully integrate the feature context. After that, by using RippleNet, we traverse the knowledge graph, filter the user preference distribution and form a set of pre recommended nodes with multi_hop nodes. Finally, the prediction layer sorts the set and gets a Top_n paper recommendation. In the experiments on the DBLP and Aminer datasets, the precision value of KGTE improved by an average of 2.59% over the existing baseline methods DER and 4.23% improvement in NDCG. [ABSTRACT FROM AUTHOR]

Because of the increase in the transmission voltage levels, the demand for insulation reliability of power transformers has increasingly become critical. Cellulose insulating paper is the main insulating component of power transformers. To improve the insulation level of ultrahigh voltage transformers and reduce their weight and size, reducing the dielectric constant of oil-immersed cellulose insulating paper is highly desired. Cellulose is used to produce power-transformer insulating papers owing to its excellent electrical properties, renewability, biodegradability and abundance. The dielectric constant of a cellulose insulating paper can be effectively reduced by chemical or physical modification. This study presents an overview of the foreign and domestic research status of the use of modification technology to reduce the dielectric constant of cellulose insulating papers. All the mentioned methods are analyzed in this study. Finally, some recommendations for future modified cellulose insulating paper research and applications are proposed. This paper can provide a reference for further research on low dielectric constant cellulose insulating paper in the future. [ABSTRACT FROM AUTHOR]

Paper and packaging materials a lignocellulose-based natural biodegradable polymer that spontaneously releases acetic acid, aldehydes, alcohol, and ester-based volatile organic compounds (VOCs) upon ageing and these VOCs start degrading the paper products and decline their mechanical strength properties. The reactivity of the paper of unbleached wheat straw pulp towards acetic acid and hexanal, which has been proven to have more degrading effects on paper than other VOCs, was considered in this work. The papers were exposed to these volatile compounds for 90 days in an air-tight vessel under ambient environmental conditions. The results showed that hexanal was more destructive than acetic acid with regards to cellulose degradation and depletion in the mechanical strength properties. The paper properties like, tensile, tear and burst index, viscosity, pH and carbonyl group content was measured. The growth of the carbonyl group, evidence of the ageing effects in the paper, detected more in the paper exposed to acetic acid. However, the strength of paper properties declined more with hexanal. FE-SEM analysis of the sample showed the development of pores and damage of cellulose fibre upon ageing. Similarly, the damaging effects of VOCs on cellulose, hemicelluloses and lignin were confirmed by significantly reduced peak detection through FT-IR \analysis. The high crystallinity index of the paper products due to exposure to VOCs was detected by XRD analysis, which confirmed the degradation of the low molecular weight cellulose molecule. Thus, the results are strongly recommended that VOCs that generates due to natural or artificial ageing could be the leading cause of paper degradation. [ABSTRACT FROM AUTHOR]

The scaling up of the intensity of beams of atomic clusters (nanoparticle beams) creates a new route to the fabrication of functional nanostructured materials. A challenge is to present, to the directed beam, high surface areas of the desired support material, for decoration by the clusters at local sub-monolayer densities. Then, the clusters and their properties can be preserved. Here we employ the Matrix Assembly Cluster Source (MACS) to demonstrate and characterise the deposition of lead clusters, with size of order 2 nm, into planar sheets of porous carbon paper, a material employed in electrode fabrication. We find that clusters are deposited to a depth comparable with the pore size of the carbon, ~ 50 μm, giving rise to a metal loading of ~ 0.05 mg cm−2 of carbon paper. The functionality of the nanocomposite film so created is demonstrated by its use as an electrode for the electrochemical generation of oxidising species suitable for water purification. [ABSTRACT FROM AUTHOR]

Au-Ag alloy nanostars based flexible paper surface enhanced Raman spectroscopy sensors were fabricated through simple nanostar coating on regular office paper, and the surface enhanced Raman spectroscopy detection performances were investigated using crystal violet dye analyte. Au-Ag nanostars with sharp tips were synthesized via metal ions reduction method. Transmission electron microscope images, X-Ray diffraction pattern and energy dispersive spectroscopy elemental mapping confirmed the nanostar geometry and Au/Ag components of the nanostructure. UV-Vis-NIR absorption spectrum shows wide local surface plasmon resonance induced optical extinction. In addition, finite-difference time-domain simulation shows much stronger electromagnetic field from nanostars than from sphere nanoparticle. The effect of coating layer on Raman signal intensities was discussed, and optimized 5-layer coating with best Raman signal was obtained. The Au-Ag nanostatrs homogeneously distribute on paper fiber surface. The detection limit is 10−10 M, and the relationship between analyte concentrations and Raman signal intensities shows well linear, for potential quantitative analysis. The calculated enhancement factor is 4.795×106. The flexible paper surface enhanced Raman spectroscopy sensors could be applied for trace chemical and biology molecule detection. [ABSTRACT FROM AUTHOR]

Composite materials have been widely used because of their superior properties compared to those of the original material. Separation of the constituent materials is not easy in the recycling process, and such an effort lowers economic viability. As such, this study employed a pyrolysis as a valorizing method for the composite material. Disposable paper cup waste (DPCW) was chosen as the model compound for paper-plastic composites. To offer green/sustainable features, CO2 was employed as a raw and reactive material in the pyrolysis process. It was proved that DPCW primarily composed of cellulose (outer layer) and polyethylene (inner layer). In the single-stage and multistage pyrolysis of DPCW, the CO2 reactivity in the homogeneous reaction of CO2 and DPCW-derived volatiles was not rapid. To accelerate the reaction kinetics governing the reactivity of CO2, the catalytic pyrolysis of DPCW over Ni/SiO2 was performed. The formation of syngas increases significantly, suggesting that CO2 reactivity was catalytically enhanced. The generation of syngas (enhanced by CO2) was inversely related to the DPCW oil generation, indicating that more carbon was assigned from the oil to the gaseous pyrogenic products. The study results would offer a strategic means to valorize paper-plastic composites and CO2 into energy through pyrolysis. [ABSTRACT FROM AUTHOR]

We report an innovative and facile approach to fabricating an ultrasensitive plasmonic paper substrate for surface-enhanced Raman spectroscopy (SERS). The approach exploits the self-assembling capability of poly(styrene-b-2-vinyl pyridine) block copolymers to form a thin film at the air-liquid interface within the single microdroplet scale for the first time and the subsequent in situ growth of silver nanoparticles (AgNPs). The concentration of the block copolymer was found to play an essential role in stabilizing the droplets during the mass transfer phase and formation of silver nanoparticles, thus influencing the SERS signals. SEM analysis of the morphology of the plasmonic paper substrates revealed the formation of spherical AgNPs evenly distributed across the surface of the formed copolymer film with a size distribution of 47.5 nm. The resultant enhancement factor was calculated to be 1.2 × 107, and the detection limit of rhodamine 6G was as low as 48.9 pM. The nanohybridized plasmonic paper was successfully applied to detect two emerging pollutants—sildenafil and flibanserin—with LODs as low as 1.48 nM and 3.45 nM, respectively. Thus, this study offers new prospects for designing an affordable and readily available, yet highly sensitive, paper-based SERS substrate with the potential for development as a lab-on-a-chip device. [ABSTRACT FROM AUTHOR]

Background: The mobile device diffusion has increasingly highlighted the opportunity to collect patient-reported outcomes (PROs) through electronic patient-reported outcomes measurements (ePROMs) during the clinical routine. Despite the ePROMs promises and advantages, the equivalence when a PRO measure is moved from the original paper-and-pencil to the electronic version is still little investigated. This study aims at evaluating equivalence between PROMs and ePROMs self-administration in people with multiple sclerosis (PwMS); in addition, preference of self-administration type was evaluated. Methods: The Manual Ability Measure-36 (MAM-36) and Fatigue Severity Scale (FSS) were selected for the equivalence test. The app ABOUTCOME was developed through a user-centered design approach to administer the questionnaires on tablet. Both paper-and-pencil and electronic versions were randomly self-administered. Intrarater reliability between both versions was evaluated through the intraclass correlation coefficient (ICC, excellent for values ≥ 0.75). Results: Fifty PwMS (35 females) participated to the study (mean age: 54.7±11.0 years, disease course: 27 relapsing-remitting and 23 progressive; mean EDSS: 4.7±1.9; mean disease duration: 13.3±9.5 years). No statistically significant differences were found for the means total scores of MAM-36 (p = 0.61) and FSS (p = 0.78). The ICC value for MAM-36 and FSS was excellent (0.98 and 0.94, respectively). Most of participants preferred the tablet version (84%). Conclusion: The results of the study provide evidence about the equivalence between the paper-and-pencil and electronic versions of PROs administration. In addition, PwMS prefer electronic methods rather than paper because the information can be provided more efficiently and accurately. The results could be easily extended to other MS PROs. [ABSTRACT FROM AUTHOR]

Flexible and small-scale energy storage technologies are critical for future applications such as wearable electronics. In this context, paper has emerged as a lightweight, low-cost, and ecologically friendly flexible substrate for energy storage devices. This paper presents a simple method for fabricating a micro-supercapacitor (MSC) using a wax printing approach that can achieve high resolution without requiring complex processes. In addition, the developed MnO2–Au-paper (MAP) microelectrodes with high porosity exhibit enhanced charge and ion transfer while maintaining a stable flexibility. The solid-state micro-supercapacitor delivers a very large areal capacitance of 624.32 mF cm−2 at 0.2 mA cm−2 and is stable under external stress. The highest energy and power densities obtained for the present MSCs (55.5 μWh cm−2 and 1.59 mW cm−2, respectively), are much larger than those previously reported for pseudocapacitive MSCs, including flexible ones. [ABSTRACT FROM AUTHOR]

Cellulosic-based materials such as hemp fabric and paper have combined characteristics of renewability, biodegradability, flexibility, and recyclability. However, regular products are not suitable for use in unconventional applications due to inherent limitations, and accordingly, enabling new capabilities is a necessity. To this end, the conversion of regular hemp fabric and paper into high-strength products with hydrophobic function via surface engineering was explored. The fluorinated waterborne polyurethane (FWPU) emulsions were first synthesized as functional coatings by in-situ polymerization. The structure and properties of the FWPU emulsion and film were characterized by FTIR, XRD, SEM, TG, and XPS. The results showed that the grafting of perfluorooctanol imparts WPU film excellent hydrophobicity, and the water contact angle increases from 71.2° to 105.9°. After the FWPU coating, the water contact angles of the hemp fabric and paper increase from 0° to 117.1° and 112.8°, respectively. Quite encouragingly, the coating generation of waterborne polyurethane-derived functional additives led to the increase of mechanical strength by more than 23% and 82%, in the case of qualitative filter paper and hemp fabric. Meanwhile, the folding strength of filter paper is increased by 132 times. Overall, this functionalized waterborne polyurethane coating would direct paper and hemp fabric toward diversified applications. [ABSTRACT FROM AUTHOR]

Environmental and health concerns are driving food packaging to reduce the use of poly- or perfluorinated compounds and petroleum-based polymers. Here, we successfully obtained good oil-proof paper by combining cellulose nanofibril (CNF) film with filter paper through film transfer. The process was not only facile but also did not require chemical reagents other than water. To achieve the kit number 12, the basis weight of the CNF film was 2.1 g/m2, which was much less than the amount required for coating. The calendering process further reduced the pores thus improving the oil resistance of the film transfer paper. At a calendering pressure of 20 N/mm, only 1.4 g/m2 of the CNF film was required for kit number 12. This study provides a new way for the application of CNF in the field of oil resistance. [ABSTRACT FROM AUTHOR]

Up to now, it is always a delicate and challenging task to clean and protect Xuan paper ink painting. Xuan paper is composed of cellulose with a rough surface and easy to absorb dust, which leads to poor cleaning effect and irreversible damage in traditional cleaning process. Hydrogel is one of the most effective tools to clean the artworks. However, in the practice of cleaning Xuan paper, most hydrogels cannot achieve fine cleaning result due to the interfacial adhesion issues. Herein, to protectively and effectively clean Xuan paper, using physical yet strong poly(vinyl alcohol)/poly(N-(2-hydroxyethyl) acrylamide) (PVA/PHEAA) hydrogel with suitable stiffness as the model, the interfacial adhesion between hydrogel and Xuan paper was systematically investigated, and various technologies were used to evaluate the cleaning effect. A critical interfacial adhesive energy (< 4 J/m2) is found to achieve the protective and effective cleaning purpose. To the best of our knowledge, this is the first report to estimate the adhesion of hydrogel on the cleaning of paper artwork, which will provide a new viewport in the conservation practice. [ABSTRACT FROM AUTHOR]

Due to the hydrophilic nature of paper mulch, it is easy to absorb water during use, which will reduce its mechanical properties and durability, thus affecting its performance. Therefore, the development of paper mulch is hindered. In this paper, in order to improve the hydrophobic performance of paper mulch, we successfully prepared superhydrophobic silicon dioxide/paper mulch by simple, efficient and environmentally friendly solution immersion method without the introduction of adhesive. The contact Angle and rolling Angle between the prepared super hydrophobic paper mulch and water are 156.4° and 1.8°, respectively. The water drop is easy to roll on its surface, and has excellent water drop bouncing performance, which can play an excellent water-repellent function. Studies have shown that the superhydrophobicity of silicon dioxide/paper mulch is less affected by its surface roughness, mainly because the surface covered by a layer of silicon dioxide reduces the surface energy of the paper mulch, and the silicon dioxide on the surface of the paper mulch is enough to reduce the damage of aging on the paper mulch. In addition, the decrease in the contact angle of the SiO2/paper mulch and the increase in the rolling angle after aging are due to the decrease in the amount of SiO2 adhesion on the surface of the paper mulch and the increase in the degree of exposure of fiber bundles. Studies have found that the superhydrophobic paper mulch can reduce the influence of its own aging on its rolling angle after being subjected to friction. [ABSTRACT FROM AUTHOR]

Pine needle waste-based ethylene scavenging paper was developed by incorporating nanomaterial halloysite nanotube (HNT) and micro-fibrillated cellulose (MFC). The ethylene scavenging capacity was evaluated with the banana storage in the developed nanocomposite paper. The quality of bananas, such as color, physical appearance, total soluble solids (TSS), pH, and weight loss, was evaluated during banana storage. The PN/MFC/HNT 30% based packaging system delayed the ripening and senescence process. The color of banana, TSS, and pH was stable during the storage period in the PN/MFC/HNT 30%. In contrast, the banana in control PN packaging has accelerated quality decaying have been observed. The ethylene content was in the control PN packaging recorded at 633.67 μL L−1 and 424.12 μL L−1 in the PN/MFC/HNT 30% package on the last day of storage analysis. The nanocomposite paper with the waste pine needle with HNT and MFC has observed an excellent ethylene scavenging capacity with more than 200 μL L−1 on the 10th day of storage analysis. The developed paper has high potential in the active packaging application for fresh produces. [ABSTRACT FROM AUTHOR]

Efficient removal of mold stains becomes an important research topic for paper conservation. In this study, a cleaning scheme based on the combination of bioenzymes and biosurfactants was explored. Morphological and molecular biology identifications were first jointly applied to identify the dominant strains sampled from five ancient books that are stored in the same environment. Cellulolytic experiments were then conducted to evaluate the cellulose degradation ability of the strains according to the cellulolytic digestive index. Finally, paper Mockups for the ancient books were constructed to investigate the most effective combination of bioenzymes and biosurfactants in removing mold stains as well as its effect on the paper's physical properties. The result concluded that the combination of 3% papain, 7% of sophorolipid or 7% of betaine, and distilled water, achieved optimal stain removal effect with over 50% cleaning rate at 35 °C, after 30 min of infiltration. The maximum color difference of the paper material after cleaning was around 0.60, pH was between 7.45 and 7.79, and no significant changes in tensile strength were observed. At the same time, Sophorolipid and Betaine both have superior deacidification, anti-acidification, anti-aging, and reinforcement capabilities, which can provide extra support to the fibrous structure in addition to cleaning the paper materials. The microbial contamination cleaning agent proposed in this study shows promising application prospects in conserving mold-contaminated paper artifacts. [ABSTRACT FROM AUTHOR]

Small, single-layer microfluidic paper-based analytical devices (µPADs) offer potential for a range of point-of-care applications; however, they have been limited to low flow rates. Here, we investigate the role of laser cutting paper channels in maximizing flow rate in small profile devices with limited fluid volumes. We demonstrate that branching, laser-cut grooves can provide a 59.23–73.98% improvement in flow rate over a single cut, and a 435% increase over paper alone. These design considerations can be applied to more complex microfluidic devices with the aim of increasing the flow rate, and could be used in stand-alone channels for self-pumping. [ABSTRACT FROM AUTHOR]

An efficient process for recycling paper and cardboard wastes via dissolution in N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) system and regeneration from solutions to obtain hydrogels has been developed. Pretreatment of waste paper has been carried out by thermal defibrillation of waste paper in water and homogenization to obtain fibrous samples. The dissolution of fiber materials was performed in two ways by varying the process temperature and the way the reagents were added. Regeneration from solutions was carried out by spontaneous gelation without the use of antisolvents, at room temperature and atmospheric pressure. As a result, hydrogels were obtained which differed in color and transparency depending on feedstock. The physicochemical properties of the hydrogels were characterized. It was shown that they were steady in an aqueous medium, capable of retaining a significant amount of water (over 4000 wt %), and they were porous systems which was confirmed by scanning electron microscopy. According to a wide-angle X-ray scattering, the crystallographic structure of the pristine waste paper samples corresponded to a structural modification of cellulose I. Regenerated samples as freeze-dried hydrogels had the structure of cellulose II. A functional and an elemental composition studied with FTIR spectroscopy and an energy-dispersive X-ray microanalysis characterized these hydrogels as the cellulose samples containing small amount of inorganic impurities. The resulting hydrogels had a system of open pores of different sizes, and this predetermined their use as adsorbents and active matrices. [ABSTRACT FROM AUTHOR]

With the exponential growth of the volume of scientific literatures, academic evaluation is becoming one of the important problems of scientometrics. Considering the influence of disruption of papers, in this paper, we propose a disruption based PageRank (DPRank) model to rank the scientific significance of scientific papers. The disruption value of a paper is calculated by the local network structure of the paper in the citation network. DPRank model treats each citation differently based on paper's temporal information and disruption value. In DPRank model, the scores delivered from a paper's upstream nodes decay exponentially with the time gap between the publication time and reference time, and the decay rate is proportional to the paper's disruption value. We use the APS data set and some highly valued papers as benchmarks to evaluate the performance of the proposed DPRank model. The experimental results show that the DPRank model has a relatively better performance for both old and newly published papers, and can outperform other methods in identifying the benchmark papers. [ABSTRACT FROM AUTHOR]

In this research, we design and implement a small, convenient, and noninvasive paper-based microfluidic sweat sensor that can simultaneously detect multiple key biomarkers in human sweat. The origami structure of the chip includes colorimetric and electrochemical sensing regions. Different colorimetric sensing regions are modified with specific chromogenic reagents to selectively identify glucose, lactate, uric acid, and magnesium ions in sweat, as well as the pH value. The regions of electrochemical sensing detect cortisol in sweat by molecular imprinting. The entire chip is composed of hydrophilically and hydrophobically treated filter paper, and 3D microfluidic channels are constructed by using folding paper. The thread-based channels formed after the hydrophilic and hydrophobic modifications are used to control the rate of sweat flow, which in turn can be used to control the sequence of reactions in the differently developing colored regions to ensure that signals of the best color can be captured simultaneously by the colorimetric sensing regions. Finally, the results of on-body experiments verify the reliability of the proposed sweat sensor and its potential for the noninvasive identification of a variety of sweat biomarkers. [ABSTRACT FROM AUTHOR]

The valorization of paper mill sludge (PMS) is the main goal of this study. The emissions of PMS continue to increase at global scale, especially from packaging paper and board sectors. The raw sludge was used to prepare an adsorbent to remove toxic pollutants from wastewater, the methylene blue (MB), an organic dye. Firstly, the physico-chemical characterization of PMS was done determining the crystalline phases of PMS fibers, the content of main elements, and the pH zero point charge, which was determined at around pH 7. The adsorption of MB on PMS powder was studied at 18 °C with an agitation of 200 rpm, being the best operating conditions 30 min of contact time, 250 mg L−1 of initial MB concentration and 0.05 g in 25 mL of adsorbent dose. Experimental data of MB adsorption was fitted to Langmuir and Freundlich isotherm equations. The Langmuir model was more accurate for the equilibrium data of MB adsorption at pH 5.1. The PFOM and PSOM were adjusted to experimental adsorption kinetics data, being PSOM, which describes better the MB adsorption by PMS powder. This was confirmed by calculating the maximum adsorption capacity with PSOM, which was 42.7 mg g−1, being nearly similar of the experimental value of 43.5 mg g−1. The analysis of adsorption thermodynamics showed that the MB was adsorbed exothermically with a ΔH0 = − 20.78 kJ mol−1, and spontaneously with ΔG0 from − 0.99 to − 6.38 kJ mol−1 in the range of temperature from 291 to 363 K, respectively. These results confirm that the sludge from paper industry can be used as biosorbent with remarkable adsorption capacity and low cost for the treatment of wastewater. PMS can be applied in the future for the depollution of the effluents from the textile industry, which are highly charged with dyes. [ABSTRACT FROM AUTHOR]

Fly ash–lime–gypsum bricks are an environmentally friendly and energy-efficient alternative to burnt clay bricks. Nowadays, the scarcity of fly ash and lime adversely affects the production of fly ash bricks. To mitigate this, the current study examines incinerated paper mill sludge ash as a supplement to fly ash and lime. In the current study, in blend 1, coal fly ash is replaced by incinerated paper mill sludge ash (2.5–30 wt%), and in blend 2, lime is completely replaced by incinerated paper mill sludge ash (2.5–15 wt%). Based on Indian standards, bricks were tested for compressive strength, water absorption, weight density, percentage voids, efflorescence, drying shrinkage, dynamic modulus of elasticity, and impact energy. Before developing bricks, the materials have to be examined by X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, thermogravimetry differential thermal analysis, and scanning electron microscope techniques. Results from X-ray diffraction showed that higher replacement of incinerated paper mill sludge ash does not produce any phase transformation and merely improves porosity, which reduces weight. Higher replacement of incinerated paper mill sludge ash leads to a reduction in strength and a higher water requirement. The study found that incorporating incinerated paper mill sludge ash at replacement 2.5–15 wt% in blend 1 and 2.5–5 wt% in blend 2 satisfied the building brick requirements. By incorporating incinerated paper mill sludge ash into bricks, the brick industry can produce sustainable bricks that utilize resources effectively. Graphical abstract illustrating the reuse of incinerated paper mill sludge ash in the manufacturing of building bricks to minimize the demand for fly ash and lime. The visual shows the drawbacks of paper mill sludge in land dumping, the suggested methodology for reusing incinerated paper mill sludge ash to minimize environmental degradation, improved sustainability through waste utilization, its benefits, and the characterization of bricks. [ABSTRACT FROM AUTHOR]

Congestion is a well-known economic phenomenon in which excessive inputs lead to a decrease in the maximum possible outputs. This study analyzes the relationship between congestion and overinvestment using a data envelopment analysis framework to reveal that some congestion can be eliminated by increasing inputs. The proposed approach classifies congestion into two categories, relative and absolute congestion, depending on the possibility of eliminating congestion by increasing inputs. Corresponding methods for identifying and measuring congestion are proposed and employed for empirical analyses examining China's papermaking and paper products industry. We find that most congestion in 2013–2016 is in the relative congestion and could be eliminated by increasing inputs. The primary causes of congestion are identified based on our analysis and corresponding policy suggestions are proposed for eliminating congestion. [ABSTRACT FROM AUTHOR]

The use of active packaging has attracted considerable attention over recent years to prevent and decrease the risk of bacterial and viral infection. Thus, this work aims to develop active packaging using a paper coated with green-synthesized silver nanoparticles (AgNPs). Effects of different silver nitrate (AgNO3) concentrations, viz. 50, 100, 150, and 200 mM (AgNPs-50, AgNPs-100, AgNPs-150, and AgNPs-200, respectively), on green synthesis of AgNPs and coated paper properties were investigated. A bio-reducing agent from mangosteen peel extract (ex-Garcinia mangostana (GM)) and citric acid as a crosslinking agent for a starch/polyvinyl alcohol matrix were also used in the synthetic process. The presence of AgNPs, ex-GM, and citric acid indicated the required synergistic antibacterial activities for gram-positive and gram-negative bacteria. The paper coated with AgNPs-150 showed complete inactivation of virus within 1 min. Water resistance and tensile strength of paper improved when being coated with AgNPs-150. The tensile strength of the coated paper was found to be in the same range as that of a common packaging paper. Result revealed that the obtained paper coated with AgNPs was proven to be effective in antibacterial and antiviral activities; hence, it could be used as an active packaging material for items that require manual handling by a number of people. [ABSTRACT FROM AUTHOR]