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Mitigation of global warming, energy security and industrial competitiveness urge the energy-intensive pulp and paper industry (PPI) to transform energy use practices. This study investigates how the PPI has responded to the need for the energy transition in the 2000s. Finland and Sweden as forerunners of energy-efficient operation and decarbonization of the PPI are used as target countries. Understanding of changes in energy consumption is complemented using decomposition analysis (Logarithmic Mean Divisia Index Method) and the energy efficiency index approach. Analysis of companies’ investments in energy technologies is used for explaining changes in energy production. Evidence of significant development towards the more sustainable operation of the PPI was found. Energy consumption per produced unit has decreased, i.e., energy efficiency has improved. Fossil fuels have been partially replaced with bio-based alternatives. Thus, the CO2 intensity has decreased substantially. The generation of renewable electricity has increased in both countries. Examples of Finland and Sweden indicate that the PPI has great potential to contribute to CO2 emission reduction worldwide in the future as energy efficiency can be further improved, and the share of fossil fuels can be decreased increasing the use of biofuels and self-generated green electricity at least in kraft pulp mills.

The construction industry had approached a critical limit which led to the increase of cement production. The production of cement would cause a broader environmental implication. Cement production is a major source of carbon dioxide emission. Carbon dioxide gas contributes about 63.33% of global warming since the production of one ton of cement would emit about one ton of carbon dioxide to the environment. To mitigate this issue, the research community has investigated the use of waste materials that possess similar chemical properties with cement content as a material for partial cement replacement. The use of rice husk ash has shown to be a contending candidate in the literature. Therefore, this paper attempts at reviewing the performance of rice husk ash as partial cement replacement. It could be observed from the literature that concrete with 5% up to 15% of rice husk ash showed an equivalent performance to ordinary concrete in compressive, flexural, and tensile strength. Thus, rice husk ash can be used as a material replacement in concrete and reduces pollution that originates from cement production and open burning of rice husk.

While basic concepts of paper-based microfluidic analytical devices (μPADs) have appeared considerably, elemental technology development is worth working from different specialized points of view. Herein, we show that 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized cellulose nanofiber (TOCN) can be reasonably used as a module of μPADs; we adopted a biochemical reaction of indigo formation by oxidation of indoxyl acetate (IDA) via its hydrolysis with acetylcholinesterase (AChE) as an example. First, we demonstrate that TOCN stably stores unstable AChE and IDA when dried and acts as a biochemical reaction field when wet. The thixotropic nature of TOCN aqueous dispersion gave inkjet printability, which will facilitate the μPADs production. The exchange of substances in the wet TOCN network took more time than in solution, but this can be read as control of reaction kinetics. Finally, we constructed semiquantitative μPADs for an organic phosphorus pesticide. We illustrate that by mounting TOCN, various functions can be incorporated on one sheet of paper to lead to the extension of design flexibility and universal use for μPADs.

Around 60% of the paper worldwide is made from recovered paper. Especially adhesive contaminants, so called stickies, reduce paper quality. To remove stickies but at the same time keep as many valuable fibers as possible, multi-stage screening systems with several interconnected pressure screens are used. When planning such systems, suitable screens have to be selected and their interconnection as well as operational parameters have to be defined considering multiple conflicting objectives. In this contribution, we present a Mixed-Integer Nonlinear Program to optimize system layout, component selection and operation to find a suitable trade-off between output quality and yield.

Many organic residues are being wasted since they are not given a comprehensive management; anaerobic digestion is an alternative to reduce the impact of these residues, and to produce biogas. The chapter includes the state of art about biogas and energy production, and later, the analysis of a study case focusing on the use of pulp and paper wastes to produce biogas. The study was carried out through anaerobic digestion at a bench scale using three temperature phases to treat primary and secondary sludge, establishing operational parameters such as temperature, retention time, and organic loadings. Monitoring of volume, methane concentration in the biogas, volatile solids reduction, volatile fatty acids during the process, the performance of the process in function of methane produced per volatile solids removed is calculated. This case study shows that it is feasible to use the sludge from the company’s wastewater treatment plant (WWTP) for the generation of biogas, thus reducing waste management problems.

Micro-cracks are inherently present in concrete, leads to debilitation of structures. Methods used for managing micro-cracks have a certain degree of toxicity and also possesses certain drawbacks that made them not completely efficient. Bacterial technique when used in fresh concretes results in calcite precipitation in voids and consequently improves the strength and lowers permeability of concrete. Bio- cement is the combination of Bacillus pasteurii 5% and nutrients Urea, Calcium Lactate 95%. In this study by adding 0.5, 1, 1.5 and 2% Bio- cement by weight of cement and observed compressive strength, flexural strength values after 7 and 28 days of curing for M25 grade of concrete.

Writing and presenting results is important for any research work. Publishing is not enough; it should be written clearly and consistently for others to read and cite. We present a review of different techniques, for improving the writing in research papers intended for publishing. These include how to write the title, whether to use active or passive voice, how long sentences should be, how to present the uncertainty, understanding the International System of Units (SI) writing conventions, how to assign authorship, how to effectively use references, how to present the work, and how to publish it in a journal. This paper is a summary of the main and most recent recommendations in the scientific field on how to write a research paper to increase its impact.

Supercapacitors are favored by researchers because of their high power density, especially with the acceleration of people's life rhythm. However, their energy density, especially from the point of view of the whole energy storage device, is far lower than that of commercial batteries. In this work, a kind of customizable full paper-based supercapacitor device with excellent self-healing ability is fabricated by simple and low-cost screen printing, electropolymerization and dip coating methods. The resultant separator-free supercapacitor device exhibits both ultrahigh gravimetric and areal specific energy (power) densities of 39 Wh kg−1 (69 kW kg−1) and 692 μWh cm−2 (236 mW cm−2), achieving excellent supercapacitor performance. Notably, the addition of vitrimers endows the whole device with outstanding self-healing properties, which is helpful for enhancing the adaptability of the device to the environment. In addition, this kind of paper-based device also displays good photothermal and electromagnetic shielding performances. These striking features make paper matrix composites attractive in the fields of supercapacitors, medical photothermal treatment and electromagnetic shielding.

Diesel Particulate filters are considered one of the most efficient technologies to reduce particulate matter emitted by diesel engines. In this paper we study the development of catalytic ceramic papers based on Mn-Ce and their applications as soot particle filters in bench scale tests. Ceramic papers were prepared by a dual polyelectrolyte papermaking method and were impregnated with Mn and Ce precursors through a wet-spray procedure using a commercial fogger. Catalytic ceramic papers were tested as catalysts for the combustion of soot, which was obtained both from the burning of diesel fuel and directly from a bench test. In addition, the filtering capacity of catalytic ceramic papers was tested through opacity measurements by placing the ceramic papers in a suitable case at the end of the engine. Mn-Ce based catalysts were active in the soot combustion. The addition of citric acid considerably improved the catalytic performance of all the systems studied. This beneficial effect of citric acid is related to an improvement in the distribution of the catalytic material onto the ceramic fibers, being the mixed equimolar oxide Mn-Ce the most active catalyst.

Photonic crystals film that possesses periodic dielectric structure have shown great prospect in developing environmentally friendly paper alternatives due to the unique properties of dye free and non-photobleaching, but their practical application is limited by the weak interaction between colloidal particles. Although some progress has been obtained, it is still a challenge to develop photonic paper with the desired mechanical and optical properties. Herein, multifunctional hard core/soft shell nanoparticles with controlled size are fabricated by semi-continuous seed emulsion polymerization method. Compared with convention colloidal particles, these core/shell nanoparticles can facile self-assemble into large-scale dense ordered structure film via dried at room temperature due to the relatively low glass transition temperature (Tg) of the shell layers. The facile fabrication route enables the continuous high-through put production of the photonic papers. The as-formed papers not only possess the capacity to solvent (water/ethanol) rewritable and multicolor painting, but also can rapidly reversible mechanochromic. Moreover, due to the good compatibility of core/shell interface, these photonic films possess excellent mechanical properties, demonstrating that this multifunctional film makes the fabrication of novel robust rewritable papers possible and enables visual monitoring of deformation degree.

A recent commentary by Santhosh and Ravindran on our paper (Int. J. Hydrogen Energy 2014, 39:10606) demonstrated that the interaction between H2 and MXene (Sc2C and Ti2C) phases are not Kubas-type and should be of weak physisorption, and thus made a conclusion that 2D Sc2C and Ti2C are not suitable for practical hydrogen storage applications. In this responses, we recalculated hydrogen adsorption on 2D Sc2C and Ti2C by using different exchange-correlation functionals. And based on the calculated results, bare MXenes (especially the Ti2C) are suitable as hydrogen storage materials at temperatures of several tens degrees lower than room temperature. And the hydrogen adsorptions on the MXenes terminated with oxygen group were also investigated. Among the Ti2C, Sc2C and their oxygen-functional counterparts, the binding energy of H2 on Sc2CO2 surface is the closest to the ideal range of 0.16–0.42 eV/H2 at ambient conditions, and thus the Sc2C with oxygen group is expected to be more suitable as hydrogen storage materials.

In recent times, it has been witnessed that wireless systems based on IoT-based have developed rapidly in various sectors. The IoT (Internet of Things) is the network in which physical devices, equipment, sensors and other objects can communicate among themselves without human involvement. The WSN (Wireless Sensor Network) is a central component of the IoT, which has proliferated into several different applications in real-time. The IoT and WSNs now have various critical and non-critical applications impacting nearly every area of our everyday life. WSN nodes are usually small and battery-driven machines. Thus, the energy effective data aggregation techniques that increase the lifespan of the network are highly significant. Various approaches and algorithms for energy-efficient data aggregation in IoT-WSN systems were presented. This paper reviews the literature with specific attention to aspects of wireless networking for the preservation of energy and aggregation of data.

Highlights • Numerical simulations of acoustophoresis in pulp flow is conducted. • Parametric study of fiber characteristics, pulp flow regimes and acoustic parameters are conducted. • A feasibility study of industrial acoustophoresis for pulp concentration is performed. • A potential concentration gain of 15% is obtained experimentally., In pulp and paper mills, mechanical processes such as screening and washing are commonly used to remove accumulated solid suspensions and concentrate the pulp. For environmental reasons and to optimize paper production, an emerging challenge is to develop alternative methods to concentrate paper pulp between 3 % and 6 % consistency for which the mixed pulp-water flow is complex. Among the proposed solutions in the literature, solutions based on acoustic levitation, also referred as acoustophoresis, of low-consistency pulp have been demonstrated as a potential solution for efficient pulp concentration and water recirculation. However, no sensitivity analysis on the ultrasound and physical parameters was proposed, limiting the extension to a realistic application. Thus, this paper presents a numerical modeling of acoustophoresis for pulp flow concentration in a pipe. For this purpose, the pulp flow is defined as a pseudo-homogenous fluid with a turbulent Low Re k- ∊ formalism, and the pulp particles are considered spherical and deflected by two acoustic forces, namely the acoustic radiation force and the Stokes drag force, both induced by an ultrasound wave generated along the walls of a circular pipe. The combined action of these two forces in the pulp flow enables to concentrate the particles at the center of the pipe. The influences of particle size and mechanical properties, fluid properties and ultrasound parameters are analyzed within a parametric study to optimize the particle deflection and the pulp concentration. The experimental feasibility of the industrial use of acoustophoresis for the concentration of paper pulp is demonstrated with a concentration gain up to 15 %.

Organic-rich pulp and paper mill sludge (PPMS) has the potential to become a renewable carbon source for producing alternatives to fossil-based product. In this work, PPMS treated by hydrothermal carbonization (HTC) was investigated based on its pyrolysis properties. The pyrolytic mechanism, kinetics data and product of the sample were studied using TG as well as pyrolysis tests in Py-GC/MS and a bench-scale reactor at 450, 550, and 650 °C. The results show that the thermal decomposition of feedstock is a two-stage reaction. The mean activation energy of the pyrolysis of HTC treated PPMS was estimated as 233.08 kJ/mol, which is higher than that of the pyrolysis of paper sludge reported before. The changes in enthalpies, entropies and Gibbs free energies from the reactants to the activated complex were estimated. The concentration of monocyclic aromatic hydrocarbons in the derived organic liquid fraction shows a positive correlation with the pyrolysis temperature. At 550 °C, the organic liquid fraction reached its highest yield at 13.7% with an oxygen level of 10.7 wt% and a higher heating value of 35.9 MJ/kg. The pyrolytic chars show that a molar ratio of O:C is less than 0.2, which shows potential for use as a carbon sink.

Ambient ionization of glycans is simply and efficiently achieved by spraying from an alkali metal salt-impregnated paper surface. Monosaccharides, oligosaccharides and ring glycans easily form abundant alkali metal adduct ions, and give simple and clean high-quality mass spectra. The enhancement is specific for glycans, compared to a wide variety of non-glycan compounds present in a matrix. In addition, molecular weight of unknown glycans can be further identified based on the ion mass difference of various alkali metal adduct ions from a certain compound when using a mixed salt-impregnated paper containing five cation salts. Successful determination of glycans and glycoconjugates in plant extracts, honey, blood and urine demonstrates the practicability of this approach to complicated matrices, especially biological matrices.

Thermal papers are replacing the conventional form of printing and are being extensively used across the globe. This study encompasses a non-destructive approach to examine thermal papers by using ATR-FTIR spectroscopy and Video Spectral Comparator (VSC), where the former technique helps in characterizing and discriminating different samples and the latter helps in deciphering the faded prints on thermal paper. The qualitative analysis of the spectroscopic data based on peak to peak comparison and quantitative analysis using chemometrics has been done to obtain high discriminating power. Multivariate analysis using HCA gave a discriminating power of 83.82% and PCA showed a variance of 95.64%. The strength of the study is portrayed through the decipherment of artificially and naturally faded thermal papers using VSC and analyzing the effect of different storing conditions on their rate of fading.

The development of low-cost analytical devices for on-site water quality monitoring is a critical need, especially for developing countries and remote communities in developed countries with limited resources. Microbial electrochemical cell-based (MXC) biosensors have been quite promising for quantitative and semi-quantitative (often qualitative) measurements of various water quality parameters due to their low cost and simplicity compared to traditional analytical methods. However, conventional MXC biosensors often encounter challenges, such as the slow establishment of biofilms, low sensitivity, and poor recoverability, making them unable to be applied for practical cases. In response, MXC biosensors assembled with paper-based materials demonstrated tremendous potentials to enhance sensitivity and field applicability. Furthermore, the paper-based platforms offer many prominent features, including autonomous liquid transport, rapid bacterial adhesion, lowered resistance, low fabrication cost (

We report an approach to waterborne and degradable latex polymers. Emulsion polymerization of vinyl acetate (VA) with the cyclic ketene acetal 2-methylene-1,3-dioxepane (MDO) yields polymer particles and latex-based coatings that are hydrolytically degradable due to the presence of backbone ester groups. Polymerization under mildly basic conditions (pH 8) and at low temperature (40 °C) is critical: if the in-process pH is too acidic or the temperature too high, MDO is lost to hydrolysis, but when the media is too alkaline, VA monomer rapidly hydrolyzes. When coated onto commercial paper, films of these degradable particle dispersions show excellent oil and grease resistance as compared to non-degradable, VA-only compositions. This new class of latex is therefore well-suited for the design of next-generation, biodegradable and compostable single-use food service products, as well as for other applications where the erosion or degradation of polymer-based films and coatings is required.

Function-as-a-Service (FaaS) has raised a growing interest in how to "tame" serverless to enable domain-specific use cases such as data-intensive applications and machine learning (ML), to name a few. Recently, several systems have been implemented for training ML models. Certainly, these research articles are significant steps in the correct direction. However, they do not completely answer the nagging question of when serverless ML training can be more cost-effective compared to traditional "serverful" computing. To help in this task, we propose MLLess, a FaaS-based ML training prototype built atop IBM Cloud Functions. To boost cost-efficiency, MLLess implements two key optimizations: a significance filter and a scale-in auto-tuner, and leverages them to specialize model training to the FaaS model. Our results certify that MLLess can be 15X faster than serverful ML systems [24] at a lower cost for ML models (such as sparse logistic regression and matrix factorization) that exhibit fast convergence.

Image classification is a major application domain for conventional deep learning (DL). Quantum machine learning (QML) has the potential to revolutionize image classification. In any typical DL-based image classification, we use convolutional neural network (CNN) to extract features from the image and multi-layer perceptron network (MLP) to create the actual decision boundaries. On one hand, QML models can be useful in both of these tasks. Convolution with parameterized quantum circuits (Quanvolution) can extract rich features from the images. On the other hand, quantum neural network (QNN) models can create complex decision boundaries. Therefore, Quanvolution and QNN can be used to create an end-to-end QML model for image classification. Alternatively, we can extract image features separately using classical dimension reduction techniques such as, Principal Components Analysis (PCA) or Convolutional Autoencoder (CAE) and use the extracted features to train a QNN. We review two proposals on quantum-classical hybrid ML models for image classification namely, Quanvolutional Neural Network and dimension reduction using a classical algorithm followed by QNN. Particularly, we make a case for trainable filters in Quanvolution and CAE-based feature extraction for image datasets (instead of dimension reduction using linear transformations such as, PCA). We discuss various design choices, potential opportunities, and drawbacks of these models. We also release a Python-based framework to create and explore these hybrid models with a variety of design choices.

The study sought to examine the complexities involved in the implementation of public–private partnerships in the transport sector using the experience of Intercity STC Coaches Limited and private partners in Ghana. The study seeks to contribute to the literature on public–private partnership by examining the implementation challenges associated with the partnership between a public and private transport entities. An exploratory qualitative design through semi-structured interviews and document reviews is adopted for the study. The paper uses the complexity of joint action as the theoretical framework. The study contends that the presence of a challenge, the threat of a challenge or the quest to realize an untapped opportunity offers the basis for a PPP to kick-start. Despite the ideals, there are challenges which impede the effective operationalization of partnerships. These are discussed with clear policy suggestions to address them.

The paper industry is an important sector annually consuming kilotons of nanoforms and non-nanoforms of fillers and pigments. Fillers accelerate the rate of drying (less energy needed) and product cost (increasing the load of low-cost fillers). The plastic industry is another use sector, where coloristic pigments can be in nanoform, and many food containers are made of plastic. Use of paper to wrap both wet and dry food is consumer practice, but not always intended by producers. Here we compare the release behavior of different nano-enabled products (NEPs) by changing a) nanoform (NF) characteristics, b) NF load, c) the nano-enabled product (NEP) matrix, and d) food simulants. The ranking of these factors enables an assessment of food contact by concepts of analogy, specifically via the similarities of the rate and form of release in food during contact. Three types of matrices were used: Paper, plastic ((Polylactic Acid (PLA), Polyamide (PA6), and Polyurethane (PU)), and a paint formulation. Two nanoforms each of SiO2, Fe2O3, Cu-Phthalocyanine were incorporated, additionally to the conventional form of CaCO3 that is always contained in paper to reduce cellulose consumption. Tests were guided by the European Regulation EC 1935/2004 and EU 10/2011. No evidence of particle release was observed: the qualitative similarity (the form of release) was high regarding the food contact of all NEPs with embedded NFs. Quantitative similarity of releases depended primarily on the NEP matrix, as this controls the penetration of the simulant fluid into the NEP. The solubility of the NF and impurities in the simulant fluid was the second decisive factor, as dissolution of the NF inside the NEP is the main mechanism of release. This led to complete removal of CaCO3 in acidic medium, whereas Fe and Si signals remained in the paper, consistent with the low release rates in an ionic form. In our set of 16 NEPs, only one NEP showed a dependence on the REACH NF descriptors (substance, size, shape, surface treatment, crystallinity, impurities), specifically attributed to differences in soluble impurities, whereas for all others the substance of the nanoform was sufficient to predict a similarity of food contact release, without influences of size, shape, surface treatment and crystallinity. European Union [760840] Published version The GRACIOUS project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under grant agreement No. 760840. We sincerely thank Tim Duncan of the US-FDA for providing specimen of Quantum-Dot-polymer films that enabled benchmarking of our methodology. Hubert Rauscher of EC-JRC and Danail Hristozov of GD are gratefully acknowledged for critical presubmission review. We thank Kai Werle and Svenja Berit Seiffert for performing single-particle-ICPMS analyses, Philipp Muller for supervising electron microscopy, and Elke Schumacher for performing UVVis analyses.

In the above article, a second-order convergence in the maximum norm of the two-dimensional regularized long-wave equation is proved. However, due to a wrong inequality in Lemma 3.3 used in X. Wang et al.[1], there are some fundamental errors in this paper, in particular the proof of Theorem 3.3 and the convergence Theorem are no longer correct. The present brief paper contains clarifying comments.

A flexible Pt/TiO2/γ-Al2O3 nanfiber paper (PTA) was successfully prepared by an electrospinning-coating-NaBH4 reduction method. The catalytic performance for formaldehyde (HCHO) oxidation over PTA with different Pt contents was investigated at room temperature. The results show that PTA exhibits higher catalytic activity and stability than Pt/γ-Al2O3. The TiO2 coating can promote the transformation of intermediate species and the desorption of CO2. The PTA1 with 1 wt% Pt shows the best catalytic activity and good stability. In the view of activity and cost, 0.5 wt% Pt is the optimal Pt content. The TiO2 coating not only plays an important role in improving the activity and stability of PTA, but also acts as a protective shell of γ-Al2O3 fiber, which greatly reduces the risk of alkali etching during preparation and maintains the good flexibility of PTA. The dioxymethylene (DOM), formate/carbonate species, CO are the intermediate species in HCHO oxidation over PTA. In addition, PTA exhibits good filtration performance for fine particles as well as good fluid permeability. Because of the high efficiency and flexibility of PTA composite catalytic material for HCHO oxidation with good filtration performance for fine particles, it will be a promising candidate in air purification.

In this work, some reasoning's mistakes in the paper by Kohli (doi:10.3934/jimo.2020114) are highlighted. Furthermore, we correct the flaws, propose a correct formulation of the main result (Theorem 5.1) and give alternative proofs.

The authors of the title paper (J Photochem & Photobio A:Chem 393 (2020) 112413) claim to have synthesized a toluidine tartrate (TT) crystal and examined its nonlinear optical (NLO) behavior by experimental and theoretical studies. In this critique, it is shown that the so-called TT crystal is a surface degraded material and the experimental and theoretical data contradict literature reports on the 1:1 salt of p-toluidine and l -tartaric acid.

Two-dimensional (2D) materials represent an emerging technology for transistor electronics in view of their attractive electrical and mechanical properties. This work investigates molybdenum disulfide (MoS2) based field-effect transistors (FETs) fabricated on paper substrate for designing both digital and analog circuits, such as inverter, current mirror, and Physical Unclonable Function (PUF) bitcell. Electrical measurements of fabricated devices are exploited to setup a look-up-table (LUT)-based Verilog-A model to be integrated in a commercial circuit simulator. Obtained results prove the potential of paper-based MoS2 FETs as building blocks of next-generation integrated circuits for a wide range of practical applications.

Herein, a novel paper-based chemiluminescence (CL) assay is reported using a smartphone readout for on-site and reliable analytical applications. The CL system was based on the high-performance improving effect of cobalt-imidazole metal-organic framework (CoMOF) on luminol-hydrogen peroxide (H2O2) CL emission. The CoMOF was grown on paper and used as a support for the CL reaction, which led to an intense CL emission and good reproducibility. More importantly, the stability of luminol, as the CL reagent, was greatly improved in the presence of CoMOF. This high stability, along with the high-yield CL emission, makes the device highly suitable for commercialization. Furthermore, using a smartphone as the detector for the developed device made the process easier and more accessible for public usage. In this work, the new paper-based CL smartphone device was used for the detection of the total phenolic content of food samples. Phenolic compounds (PC) are hydroxyl radical scavengers that can effectively quench the CL emission of the luminol–H2O2–CoMOF system. After optimizing the reaction conditions, the system could detect PC at the μg mL−1 level. Detection limits of 0.12, 0.28, 0.46, 0.85, and 1.23 μg mL−1 were obtained for gallic acid, quercetin, catechin, kaempferol, and caffeic acid, respectively. This work is the first report on the practical application of smartphone CL assays for the estimation of PC. The proposed assay is an easy-to-use, low-cost, portable, and suitable assay for on-site screening purposes.

To develop functional honeycomb plates (HPs) with great thermal performance, This paper uses a heat flow meter to determine the equivalent thermal conductivity λ E of honeycomb plates (HPs) positioned horizontally under cold-above/hot-below conditions and combined with theoretical calculations, the influence mechanism of their geometric parameters on their heat transfer performance were investigated with different thicknesses h and cell wall lengths of 8 mm and 16 mm (HP8 and HP16, respectively). The results show that the thermal insulation performance of HPs with different cell side lengths varies with the plate thickness. HP8 presented a better thermal insulation performance when h = 40–60 mm. Based on this, the concepts of matching honeycomb structure and matching convection and the suggestions that according to the needs of a project, HP8 or HP16 can be reasonably selected, and the stacking of two kinds of plates can be optimized were first proposed. And it can be obtained that if the experimental λ E results of a HP are applied to a beetle elytron plate with the same thickness and honeycomb structure size, the heat insulation of the beetle elytron plate (BEP) would be superior to that of the HP. This paper lays a theoretical foundation for the research and development of multifunctional BEPs with heat insulation properties was verified. Finally, the internal influence mechanism of the difference in temperature distribution on the upper and lower surfaces and the three-dimensional size of the honeycomb cells on the matching honeycomb structure and matching convection.

Hypochlorous acid (HClO) as well as its ionic form (ClO−), representative of reactive oxygen species (ROS), are essential players in all sorts of biological processes. The abnormal level of each can lead to the onset of various diseases. Besides, Sodium hypochlorite, a commonly-used bleaching agent in our daily lives, could also result in breathing and skin problems when overexposed. Therefore, developing a molecular chemosensor for sensing HClO is of biological and environmental importance. Though many such chemosensors have been reported, new HClO chemosensors with different sensing performances may still come in handy in certain situations. In this work, we have developed a new coumarin-based chemosensor, CM-hbt, for realizing both ratiometric and colorimetric imaging detection of HClO in live cells. Notably, we further explored its application in sensing HClO in plant mung beans as well as fabricated an easy-to-use paper strip apparatus for facilitating its quick detection, which is seldomly seen in other HClO chemosensors. All the analysis results confirmed the high sensitivity and selectivity of this novel chemosensor. DFT calculations were used to decipher the underlying sensing mechanism of CM-hbt. Overall, this work presents a novel chemosensor, CM-hbt, as a colorimetric and ratiometric chemosensor for realizing imaging detection of HClO in a variety of different model systems, which highlights its broad spectrum of application potentials.

Flexible all-solid-state supercapacitors (FASSCs) have attracted much attention as power supplies for portable and wearable electronic products. Herein, we report the fabrication of a foldable, extra lightweight, flexible chopped carbon fiber paper (CFP) with a porous network structure prepared via wet-mold papermaking that can serve as a conductive substrate. The conductivity and pseudocapacitance of the electrode were improved by controlling the growth of 3D Cu(OH)2 nanorod arrays on CFP substrate. The Cu(OH)2@CFP electrode has a high specific capacitance of 421.8 mF cm−2 at a current density of 0.5 mA cm−2 with capacitance retention of 82.98% at a current density of 10 mA cm−2 after 5000 charge-discharge cycles. The FASSC manifested not only a large capacitance of 196.1 mF cm−2 at 2 mA cm−2, as well as energy and power densities of 6.97 × 10−2 mWh cm−2 and 1.6 mW cm−2, respectively, but also excellent stability of 80.3% over 5000 cycles at 5 mA cm−2. In addition, we confirmed that the FASSC has a large bending angle and can be twisted into various shapes, thereby indicating its applicability in portable and wearable electronic devices.

Coconut Shell is a waste product derived from agriculture which is utilized as bio adsorbent for treating the wastewater discharged from electroplating industries. The physio chemical characterization of raw waste water and batch adsorption study using coconut shell charcoal (CSC) with a reference to effluent characterization is conducted to identify the potential contaminant and efficiency of adsorbent. The parameters such as effective particle size of adsorbent, contact time and dosage influencing the treatment efficiency of zinc and potassium which are identified as the potential contaminant in the waste water. Increase in dosage and specific surface area with reduced particle size increases the treatment efficiency up to the approved level, beyond which the portion adsorbed which remains constant. It is apparent that a dosage of 15 g/l and duration of 90 min is satisfactory to remove 90% of phosphate and 97% of zinc for 150 µm particle size. The adsorption equilibrium data were tailored well with the Freundlich isotherm for the removal of zinc and potassium. The baseline study is manifested the potential of CSC in the reduction of zinc and potassium from the industrial waste water.

Acid pretreatment is one of the most widely used fractionation processes for lignocellulosic biomass. In this study, effect of mineral acids (SA, HA, and NA) on recovery of reducing sugar from coconut coir was studied. The independent variables such as reaction time (X1, min) and concentration of acid (X2, % w/w) were optimized using Response Surface Methodology (RSM) for maximum yield of reducing sugar. In this study, 10% w/v of coir was pretreated under various conditions of X1 and X2 by maintaining a constant temperature (121oC). A maximum reducing sugar yield greater than 55% was observed for acid pretreatment.

Microalgae-bacteria symbiotic association can provide many competitive advantages over the pure axenic culture of microalgae to obtain biofuel. This system significantly reduces an important technical constraint, including associated capital cost with the infrastructure required for maintaining pure microalgae culture. The current study aims to compare the symbiotic growth of Tetraselmis indica - Pseudomonas aeruginosa consortium with axenic growth of Tetraselmis indica in dairy wastewater (DWW). The extraction and optimization of chlorophyll-a were also investigated. The overall maximum chlorophyll-a recovery of 29.106 ± 0.045 mg L−1 was obtained through the sonification as extractant method with methanol as an extraction solvent. The chlorophyll-a content of consortium cultivated in DWW higher than the axenic pure microalgae culture (APMC). The maximum biomass yield of the consortium was achieved as 1454.88 mg L−1, which is much higher than APMC growth in DWW by 38.80%. On the 10th day, the consortium removed 87.49%, 83.76%, and 79.83% of chemical oxygen demand (COD), total dissolved nitrogen (TDN), and total dissolved phosphorus respectively. The higher biomass growth and wastewater nutrient removal exhibited by the symbiotic microalgae-bacteria consortium can be utilized in biofuel technology.

Material industry is one of the most seasoned and biggest areas in India. Removal of material factory slime is a significant issue now daily. In this exploration study, an endeavor had been made to reuse material factory ooze in concrete as halfway trade for sand to build mass use of ooze. Properties of new and solidified cement were explored by adding material factory slop in M20, M25 and M30 evaluations of cement. Material factory ooze was included rate by weight differing from 0% to 36% as a swap for fine totals (sand). Workability of solid blend diminished as ooze rate expanded past 16%. Compressive strength diminished with increment in ooze content in solid blend. Greatest measure of ooze which could be added without trading off the compressive strength altogether three evaluations of cement was 16% without settling on mean objective.

Lignin, the second most plentiful biopolymer, is produced on a large scale as the waste of the pulp and paper industries. Conventionally, lignin is incinerated for energy generation, while less tha...

The development of the preparation strategy for high-quality and large-size graphene via eco-friendly routes is still a challenging issue. Herein, we have successfully developed a novel route to chemically exfoliate natural graphite into high-quality and large-size graphene in a binary-peroxidant system. This system is composed of urea peroxide (CO(NH2)2⋅H2O2) and hydrogen peroxide (H2O2), where CO(NH2)2⋅H2O2 is used in preparing graphene for the first time. Benefiting from the complete decomposition of CO(NH2)2⋅H2O2 and H2O2 into gaseous species under microwave (MW) irradiation, no water-washing and effluent-treatment are needed in this chemical exfoliation procedure, thus the preparation of graphene in an eco-friendly way is realized. The resultant graphene behaves a large-size, high-quality and few-layer feature with a yield of ~100%. Then 4 μm-thick ultrathin graphene paper fabricated from the as-exfoliated graphene is used as an electromagnetic interference (EMI) shielding material. And its absolute effectiveness of EMI shielding (SSE/t) is up to 34,176.9 dB cm2 g −1, which is, to the best of our knowledge, among the highest values so far reported for typical EMI shielding materials. The EMI shielding performance demonstrates a great application potential of graphene paper in meeting the ever-increasingly EMI shielding demands in miniaturized electronic devices.

The paper presents the results of a study of parameters used for determining the amount of organic pollutants in wastewater flowing into a collective wastewater treatment plant with a population equivalent of about 120 000 PE. The plant constituted part of a sewage system. Assays were performed for biochemical oxygen demand (BOD5), chemical oxygen demand (CODCr), permanganete index (CODMn) and total organic carbon (TOC). In addition, the pH of wastewater and its alkalinity were determined. Sampling of incoming wastewater and measurement of physicochemical parameters were performed once a week, in the spring. A total of 44 samples of wastewater were collected. The correlations between the individual parameters and the correlations between the ratios of these parameters were determined. It was found that it was possible to estimate, with suffi cient accuracy, the values of selected parameters for determining the concentrations of organic compounds in municipal wastewater, knowing the values of other parameters in this group. Moreover, it was shown that, knowing the relationship between the analyzed parameters, one can find multiple regression equations for a given type of wastewater, which allow one to calculate the remaining relationships with a good fit, i.e. a determination factor R2greater than 0.6

Everyday, tons of food wastes are thrown to the environment constantly by people in the cities, which contain many beneficial substances. One of these beneficial wastes of unknown value is eggshells. Although the eggshells are considered negligible and not valuable material, however, the many researches that dealt with this substance proved its high potential to turn into many useful substances such as a catalyst in biodiesel preparation or as a media for adsorption of heavy metals and dyes or soil fertilizer and others. The current study highlighted the benefit possibility of white chicken eggshells (WCES) from another side, considering it as a raw material for preparing acetone one of the most important industrial solvents. The results obtained showed that this worthless raw material has a high effectiveness for acetone production by containing 94.519% by weight of calcium carbonate. The process of converting WCES to acetone was carried out in two steps, the first one were producing calcium acetate by treating it with glacial acetic acid in a batch mode reaction unit at room temperature and agitation speed, acid % excess and contact time of 200 rpm, 20% and 2 h respectively. Whereas, the next step involved conducting the process of thermal decomposition of the prepared calcium acetate at 380 °C to produce acetone in a stainless steel reactor. The results of testing the samples by the gas chromatography (GC) showed that the maximum yield of acetone is 96.395%. With these experimental results, this study presents a new idea in food waste management as one of the solid waste types by utilizing it in a useful manner to produce important materials in an economical, beneficial and environmentally friendly way, reaching to the concept of zero residue level (ZRL).

Bentonite is a favourable candidate as a sealing material in the deep geological repository to safe storage of highly radioactive nuclear waste in several countries. The high swelling characteristic made bentonite famously type of clay that extracted from smectite group with the main mineral is montmorillonite that has a double diffusion layer. The benefits of sodium bentonite like Wyoming bentonite has proven in the industry. Research on modifying the properties of calcium bentonite to high swelling clay like sodium bentonite for it be able to benefit the industry has been done. Most of the research attempted to improve the workability of calcium bentonite as an alternative material for replacing sodium bentonite in construction industry; however, very little is known about using raw calcium bentonite to improve weak soil subgrades. This paper highlighted the usage of calcium bentonite adapted in construction industry especially in soil stabilization activity and some experimental analysis has been made on the type of calcium bentonite found in British Columbia mine.

As an aromatic polymer in nature, lignin has recently attracted gross attention because of its advantages of high carbon content, low cost and bio-renewability. However, most lignin is directly burnt for power generation to satisfy the energy demand of the pulp mills. As a result, only a handful of isolated lignin is used as a raw material. Thus, increasing value addition on lignin to expand its scope of applications is currently a challenge demanding immediate attention. Many efforts have been made in the valorization of lignin, including the preparation of precursors for carbon fibers. However, its complex structure and diversity significantly restrict the spinnability of lignin. In this review, we provide elaborate knowledge on the preparation of lignin-based carbon fibers ranging from the relationships among chemical structures, formation conditions and properties of fibers, to their potential applications. Specifically, control procedures for different spinning methods of lignin, including melt spinning, solution spinning and electrospinning, together with stabilization and carbonization are deeply discussed to provide an overall understanding towards the formation of lignin-based carbon fibers. We also offer perspectives on the challenges and new directions for future development of lignin-based carbon fibers.

Graphical abstract, Introduction Face masks are regarded as effective Personal Protective Equipment (PPE) during the COVID-19 pandemic. However, the dominant polypropylene (PP)-based masks are devoid of antiviral/antibacterial activities and create enormous environmental burdens after disposal. Objectives Here we report a facile and potentially scalable method to fabricate biodegradable, breathable, and biocidal cellulose nonwovens (BCNWs) to address both environmental and hygienic problems of commercially available face masks. Methods TEMPO-oxidized cellulose nonwovens are rendered antiviral/antibacterial via covalent bonding with disinfecting polyhexamethylene guanidine or neomycin sulfate through carbodiimide coupling chemistry. Results The obtained results showed that the BCNWs have virucidal rate of >99.14%, bactericidal efficiency of >99.51%, no leaching-out effect, and excellent air permeability of >1111.5 mm s−1. More importantly, the as-prepared BCNWs can inactivate SARS-CoV-2 instantly. Conclusions This strategy provides a new platform for the green fabrication of multifunctional cellulose nonwovens as scalable bio-protective layers with superior performance for various PPE in fighting COVID-19 or future pandemics. Additionally, replacing the non-biodegradable non-antimicrobial PP-based masks with the cellulose-based masks can reduce the plastic wastes and lower the greenhouse gas production from the incineration of disposed masks.

Biorefinery is pivotal to the sustainability of modern chemical industry. However, since biomass is oxygen-enriched, new and green chemical strategies are required for expanding the biomass derived chemical space. In this work, synthesis of natural products dihydrocapsaicin and dihydrocapsiate was achieved exclusively from lignocellulosic platform chemicals. Natural products dihydrocapsaicin and dihydrocapsiate were synthesized exclusively from lignocellulosic platform chemicals, using furfural (from hemicellulose) and methyl isopropyl ketone (from cellulose) through aldol condensation-hydrolysis-hydrodeoxygenation to synthesize 8-methylnonanoic acid and then combined with vanillin derivates (from lignin). This synthesis demonstrates the feasibility of constructing natural products entirely from renewable biomass platform through green processes. The utilization of inherent functional groups of biomass demonstrates their potential to open up chemical space.

A series of four different biomass feedstock was washed and hydrothermally carbonized at temperatures of 50 °C and 150–270 °C for four hours, respectively. For the first time both the resulting solid and liquid products were characterised and evaluated in a comprehensive study. Concerning fuel properties, HTC had a higher impact on the fuel quality than washing. HTC yielded hydrochar with higher carbon content than the starting material leading to a significant increase in heating value, while washing only had a minor effect on elemental composition and heating value. Treatment temperature was found to have the highest impact on LHV and elemental composition. Both washing and HTC proved effective in reducing potassium and chlorine content, while earth alkaline, phosphorous and silicon removal was limited. Process water characterisation revealed that filtrates from washing and HTC are acidic, with acidity being increased by HTC. Electrical conductivity of the effluent was found to correlate with the amount of electrolytes Na, K, Mg and Ca in the feedstock, thereby being feedstock dependent. COD, BOD5 and TOC values determined revealed that effluent from both washing and HTC is strongly contaminated by organic matter. The organic load was significantly higher in HTC effluents. Feedstock type was found to be the main influencing factor on effluent characteristics rather than HTC temperature. Nutrients were found in low concentrations. Graphic Abstract

Embargado hasta 30/11/2023 Lithium–sulfur batteries have been recognised as highly promising next-generation batteries, due to their low cost and high theoretical energy density. Despite numerous advances in this technology over the last decade, its commercialisation is still a challenge that has not yet been achieved. Many efforts have been made to improve the problems that these batteries present, mainly by investigating different cathode manufacturing strategies, testing novel Li anodes, new additives in the electrolytes, and modified separators or interlayers. However, the characteristics of the current collectors used in the preparation of the electrodes have been rarely addressed. Three commercial collectors are commonly used in basic research on Li–S batteries: Al foil, carbon coated Al foil (Al-C), and carbon paper (gas diffusion layer, GDL). In this work, a detailed study of the electrochemical response of these commercial collectors has been carried out. The tests were carried out on two S composites formed by carbons of a different natures, commercial carbon black and synthetic N-doped graphene. In addition, the S impregnation method was different, using either melt diffusion at 155 °C or ethylenediamine as S solvent, respectively. In both systems, the results were similar – the electrodes supported on GDL delivered higher specific capacities than those supported on Al and Al-C, with minimal differences between the two. Of the different collector properties examined to explain this behaviour, namely Al corrosion, electrical conductivities, surface-level composition, and surface texture, only the latter had a significant effect in the performance of GDL-based electrodes. SEM images revealed a rough and cracked surface formed by the agglomerated carbon particles that give rise to a complex pore system, predominantly consisting of macropores. All of these features are beneficial for a better anchoring of the active material on the collector surface, in addition to enhancing the wettability of the electrolyte and favouring reaction kinetics. In contrast, the Al-based collector possesses a very smooth and non-porous surface, detrimental to both the active material-substrate interface and the active material impregnation by the electrolyte.

In order to investigate the effect of washing water pH on textile damage for delicate garments, the study was conducted such that a customer survey was first applied to randomly selected users to analyze domestic washing machine using habits of Turkish consumers. Based on the findings of the survey, the experimental study was designed in two successive phases to investigate the dimensional and mechanical behavior of certain types of delicate textiles against varying washing conditions by taking in particular, water properties, namely pH, hardness, and temperature into account, and accordingly to determine the optimized washing conditions for such textiles. Firstly, tergotometer was employed as a washing machine simulator. Within the light of the results obtained, the experimental work of the second phase of the study was conducted, which involved a domestic washing machine as a real-life scenario. All of the results, including the correlation between the data sets obtained from the tergotometer and domestic washing machine trials, were statistically analyzed using Minitab 17. The study produced some important findings regarding the effect of washing water pH on delicate textiles, in addition to an algorithm for improving the present washing program, minimizing textile damage for mainly wool and silk garments.

In this study, the effects of corrosion inhibitor of sludge produced in the process of natural gas exploitation and transportation on sulfur oxidation by Acidithiobacillus thiooxidans were studied....