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Abstract The pulp and paper manufacturing wastewater is as complicated as any other industrial effluent. A promising approach to treating water is to combine photocatalysis and membrane processes. This paper demonstrates a novel photocatalytic membrane technique for solar-powered water filtration. The method is based on creating green-prepared TiO2, and MnO2 nanoparticles (NPs) using Pomegranate peels and Seder leaf extracts and incorporation into polyvinylidene chloride to produce a novel water purification system that combines semiconductor photocatalysis with membrane filtration. The prepared heterostructure of the TiO2/MnO2 nanocomposite membrane provides photogenerated charge separation. To ensure chemical bonding at the membrane surface, Raman and Fourier transform infrared spectroscopy (FT-IR) were employed. The modified membrane’s hydrophilicity and roughness increased significantly. Additionally, the modified nanocomposite membrane’s porosity was measured. The integrated process demonstrated much higher removal of humic acid and high efficiency of wastewater treatment for pulp and paper. In sunlight, humic acid removal was 98% from synthetic wastewater. While using the produced membrane on pulp and paper effluent, these studies indicate that: in the dark, the removal was 50%, while in the sunlight, the removal increased to 70%, with a reduction in the COD from 1500 mg/L to 247 mg/L. Additionally, the TDS decreased from 1630 to 452 ppt in the sunlight. This research sheds light on how solar energy can clean wastewater from the pulp and paper industry while improving membrane separation. Also, an alternative source to sunlight was used to manufacture a photocatalytic membrane with high efficiency for wastewater treatment and an inexpensive price.

Abstract This research investigates the pulp and paper industry's transition to sustainability by valorizing unused roadside and natural grasses for paper production. Large-scale production from residual grass poses multifaceted challenges, requiring collaboration across stakeholders, from biomass collection to manufacturing. To understand key drivers and barriers within this complex system, experts from various fields, including local farmers, researchers, policymakers, and industry executives were interviewed, leading to the development of a Fuzzy Cognitive Map (FCM). The analysis explores various scenarios to assess how socio-economic, technological, and political factors influence the transition to low-carbon practices. These scenarios highlight the effects of varying levels of technology development, economic conditions, and policy support on the transition's progress and outcomes. Results show that the system is highly sensitive to shifts in socio-economic and political conditions. Political interventions play a crucial role, especially during energy crises and increased public demand for sustainable solutions. Grass-based paper production is seen as a viable pathway, but challenges such as the economic feasibility of emerging technologies remain. We recommend targeted policies to improve the economic viability of grass-based products and optimize biomass allocation between energy and bio-based products, ensuring a more balanced and sustainable transition.

Abstract This manuscript proposes the Jellyfish Search Optimization (JSO) algorithm-based Fractional Order Proportional-Integral-Derivative (FOPID) controller tuning for a paper machine headbox. The novelty of this method lies in integrating the JSO technique for optimizing the parameters of the FOPID controller to monitor and control headbox pressure and stock level efficiently and effectively. The JSO algorithm ensures optimal tuning of controller parameters by minimizing error indices such as Integral of Squared Error (ISE), Integral of Time Absolute Error (ITAE), and Integral of Absolute Error (IAE). Simulations conducted on the MATLAB/Simulink platform demonstrate that the FOPID controller tuned using JSO achieves superior performance compared to conventional PI (Proportional-Integral) and PID (Proportional-Integral-Derivative) controllers. Specifically, the JSO-tuned FOPID controller exhibited a 25% reduction in rise time, a 30% improvement in settling time, and a 20% decrease in overshoot when compared to the PID controller. Furthermore, comparative analyses with other optimization techniques, including Moth Flame Optimization (MFO), Ant Lion Optimization (ALO), and Elephant Herding Optimization (EHO), reveal that the JSO algorithm provides higher accuracy and stability in diverse operating conditions. This study underscores the efficacy of the JSO-tuned FOPID controller as a robust solution for complex industrial applications, such as paper machine headbox systems, and highlights its potential to enhance process efficiency and control precision.

Due to the scarcity of wood in some countries, it is necessary to replace it with other raw materials and at the same time use the waste material. The aim of this research is to use poppy waste straw for the efficient conversion of possible lignocellulosic materials – pulps and particleboards. Their suitability for the production of composites is assessed on the basis of selected physical or mechanical properties. Tensile strength index, burst strength index and air permeability by Gurley have been identified as critical properties of pulp made from poppy straw through two delignification methods. The better mechanical properties, i.e., tensile strength index, were achieved at 52.7 N·m/g for the sodium pulp, but the nitrate-alkali method also showed corresponding values at 45.9 N·m/g. Similar parameters to those of bagasse or similar fast-growing plants were achieved in particleboard production. The results of this research are used to evaluate poppy straw as an alternative raw material to produce biocomposites. [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]

Many studies have been conducted on measuring avian influenza viruses and their hemagglutinin (HA) antigens via electrochemical principles; most of these studies have used gold electrodes on ceramic, glass, or silicon substrates, and/or labeling for signal enhancement. Herein, we present a paper-based immunosensor for label-free measurement of multiple avian influenza virus (H5N1, H7N9, and H9N2) antigens using flexible screen-printed carbon nanotube-polydimethylsiloxane electrodes. These flexible electrodes on a paper substrate can complement the physical weakness of the paper-based sensors when wetted, without affecting flexibility. The relative standard deviation of the peak currents was 1.88% when the electrodes were repeatedly bent and unfolded twenty times with deionized water provided each cycle, showing the stability of the electrodes. For the detection of HA antigens, approximately 10-μl samples (concentration: 100 pg/ml-100 ng/ml) were needed to form the antigen-antibody complexes during 20-30 min incubation, and the immune responses were measured via differential pulse voltammetry. The limits of detections were 55.7 pg/ml (0.95 pM) for H5N1 HA, 99.6 pg/ml (1.69 pM) for H7N9 HA, and 54.0 pg/ml (0.72 pM) for H9N2 HA antigens in phosphate buffered saline, and the sensors showed good selectivity and reproducibility. Such paper-based sensors are economical, flexible, robust, and easy-to-manufacture, with the ability to detect several avian influenza viruses., (© 2022. The Author(s).)

This research investigates the pulp and paper industry's transition to sustainability by valorizing unused roadside and natural grasses for paper production. Large-scale production from residual grass poses multifaceted challenges, requiring collaboration across stakeholders, from biomass collection to manufacturing. To understand key drivers and barriers within this complex system, experts from various fields, including local farmers, researchers, policymakers, and industry executives were interviewed, leading to the development of a Fuzzy Cognitive Map (FCM). The analysis explores various scenarios to assess how socio-economic, technological, and political factors influence the transition to low-carbon practices. These scenarios highlight the effects of varying levels of technology development, economic conditions, and policy support on the transition's progress and outcomes. Results show that the system is highly sensitive to shifts in socio-economic and political conditions. Political interventions play a crucial role, especially during energy crises and increased public demand for sustainable solutions. Grass-based paper production is seen as a viable pathway, but challenges such as the economic feasibility of emerging technologies remain. We recommend targeted policies to improve the economic viability of grass-based products and optimize biomass allocation between energy and bio-based products, ensuring a more balanced and sustainable transition. [ABSTRACT FROM AUTHOR]

Guilin is a world-famous karst area characterized by a high concentration of Ca2+ in its groundwater. The disintegration of red clay plays a key role in the collapse of soil caves. In order to study the disintegration mechanisms of unsaturated red clay in Ca2+ solution, disintegration tests were conducted using a self-made disintegration apparatus. The soil samples are placed on the sieve plate of the disintegration apparatus, and a tensile meter records the real-time change of samples mass to calculate the disintegration rate. XRD analysis and filter paper method were employed to determine the mineral composition and matric suction of red clay, respectively. The results show that the matric suction decreases with increasing moisture content and increases with the void ratio. When the matric suction exceeds 965 kPa, disintegration is markedly intense, and the disintegration rate shows no significant correlation with Ca2+ concentration. When the matric suction is below than 965 kPa, the disintegration rate increases from 0.057 to 3.027 g/s with the increase of Ca2+ concentration. The disintegration of red clay with high matric suction is primarily attributed to the rapid ingress of water molecules and the compression of air due to matric suction, resulting in tensile stress. The disintegration of red clay with low matric suction is primarily caused by the reduction in the diffusion layer thickness of clay particles and the weakening of interparticle attraction due to Ca2+. [ABSTRACT FROM AUTHOR]

In many animals, early-life decisions influence long-term fitness. Mantidflies are spider egg predators; their tiny larvae climb aboard spiders to find eggs, but little is known about how they find spiders. We tested the hypothesis that mantidfly larvae (Dicromantispa sayi) detect and respond to substrate-borne spider cues (e.g., silk and/or excreta). We presented larvae with filter paper exposed to different types of spiders (adult female, adult male, or juvenile Habronattus trimaculatus jumping spiders) versus a no-cue control. Larvae spent more time on filter paper with spider cues. We then tested the hypothesis that mantidflies make finer distinctions between spiders when given direct choices between these cues. Larvae did not discriminate between sexes but spent more time (and exhibited more phoretic behavior) on filter paper with female or male cues compared with juvenile cues. While this suggests that mantidflies actively seek out adult spiders, we also found that adult spiders were more active than juveniles and may have simply deposited more silk and excreta, providing a stronger cue to detect. We discuss these findings in the context of the risks and benefits of different spider hosts, and how early-life spider-searching strategies may shape a mantidfly's long-term fitness. [ABSTRACT FROM AUTHOR]