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Chemical crosslinking is an established method for improving the wet performance of paper. In the chemical crosslinking process, covalent bonds are formed between cellulosic surfaces. The formed intra- and interfiber bonds increase the paper's wet strength and reduce its water absorptivity. The majority of published studies concern crosslinking treatments with glyoxal, citric acid (CA), or with 1,2,3,4-butanetetracarboxylic acid (BTCA). The most severe disadvantage of the crosslinking treatments with glyoxal, CA, and BTCA is that the formed crosslinks make the fibers and the paper more brittle. This downside effect has largely impeded the utilization of crosslinking in paper and paperboard making. In the present study, handsheets made from Nordic bleached softwood kraft pulp (NBSK) were crosslinked with methylated 1,3-dimethylol-4,5-dihydroxyethylene urea (mDMDHEU), which is commonly used in cotton fabric finishing. Similar to using glyoxal and citric acid, crosslinking with mDMDHEU notably increased the handsheet wet strength and decreased the water absorption. Compared to the use of glyoxal or CA, the crosslinking with mDMDHEU did not make the handsheets that brittle. These results suggest that mDMDHEU could be a more viable crosslinking agent for improving the wet performance of paper products. [ABSTRACT FROM AUTHOR]

The use of paper as a smart support in the field of electrochemical sensors has been largely improved over the last 15 years, driven by its outstanding features such as foldability and porosity, which enable the design of reagent and equipment-free multi-analysis devices. Furthermore, the easy surface engineering of paper has been used to immobilize different bioreceptors, through physical adsorption, covalent bonding, and electrochemical polymerization, boosting the fine customization of the analytical performances of paper-based biosensors. In this review, we focused on the strategies to engineer the surface of the paper for the immobilization of (bio)recognition elements (eg., enzymes, antibodies, DNA, molecularly imprinted polymers) with the overriding goal to develop accurate and reliable paper-based electrochemical biosensors. Furthermore, we highlighted how to take advantage of paper for designing smart configurations by integrating different analytical processes in an eco-designed analytical tool, starting from the immobilization of the (bio)receptor and the reagents, through a designed sample flow along the device, until the analyte detection. [ABSTRACT FROM AUTHOR]

Holes and defects can greatly reduce the mechanical properties of multilayer graphene sheets under different loading conditions due to the stress concentration near the hole edge in each in-plane sheet and the lack of interlayer carbon–carbon bonds between the layers. Here, we report a novel design of multilayer open-hole graphene papers (MLGPs) formed through interlayer covalent bonding at the hole edges of multilayer open-hole graphene sheets (MLGSs) under high temperature using molecular dynamics (MD) simulations. Our MD results show that the hybrid sp2–sp3 interlayer bonds of MLGPs can significantly improve their both tensile strength and interlayer shear strength. The tensile strength and interlayer shear strength of MLGPs increase by around 20% and 3 times by comparison with those of MLGSs with the same number of layers, respectively, which mainly depends on the uniformity of their interlayer bond distribution. This study can provide an effective way to improve the mechanical performances of multilayer graphene sheets with flaws and also offer corresponding guidance for the design of MLGS-based nanocomposites. [ABSTRACT FROM AUTHOR]

Most technologies to produce multifunctional paper involved the defect of poor uniformity and stability. Herein, a high stability multi-functional cellulose-based paper was developed via a multiple chemical modification derived from waste bagasse. Firstly, the acetoacetyl groups was anchored on the surface of bagasse cellulose fibers by a heterogeneous transesterification. Then, paper was made based on these modified fibers. The fluorophore and gentamicin sulfate (Gen) were bonded in-situ to the paper through Hantzsch reaction and the form of enamine bond, respectively. The resulting paper exhibited excellent multifunctional properties, such as fluorescence property, antibacterial property and hydrophobic property. These properties are very stable to external environments. In addition, relatively mild surface modification has no obvious effect on fibers and shows similar whiteness and stiffness properties as that of the CAA paper. Thus, these novel functional papers held great potential for many fields such as food packaging, anti-counterfeiting, and other specialty papers. [Display omitted] • Multifunctional paper was fabricated via multiple chemical modification. • Modification showed no effect on whiteness and stiffness properties of CAA paper. • The covalent bond connection endowed paper stable to external environments. • Multifunctional paper held great potential for many fields. [ABSTRACT FROM AUTHOR]

Alkenyl Succinic Anhydride (ASA) is a sizing agent used in papermaking to increase the water repellency of paper. Almost 60 years after the introduction of the chemical in papermaking, scientists still have differing views on how ASA interacts with cellulose. Several experiments were conducted to bring more clarity to the ASA sizing mechanism, especially on the contentious question of ASA-cellulose covalent bonding or the esterification reaction between ASA and cellulose during papermaking. Herein, research papers and patents, including experiments and results, from the 1960s to 2020 were reviewed. Our investigation revealed that the ester bond formation between ASA and cellulose is insignificant and is not a prerequisite for sizing effectiveness; the main ASA-related material found in sized paper is hydrolyzed ASA or both hydrolyzed ASA and ASA salt. In addition, ASA emulsion stability and ASA emulsion retention are important for sizing efficiency improvement. [ABSTRACT FROM AUTHOR]

Microfluidic paper-based analytical devices have been widely used for immunoassays, especially in resource-limited settings. Antibodies that have been immobilized on the cellulose surface by physical adsorption become unstable as a result of antibodies’ desorption caused by the washing process and lose their activity. In this paper, we present a new approach for the covalent immobilization of antibodies on the paper surface. More precisely, sodium periodate (NaIO 4 ) was used to activate the cellulose for introducing aldehyde groups. Antibodies were bound to the oxidized cellulose paper surface through imine formation (Schiff base) between the aldehyde groups and the primary amine groups of the antibody. Thus, using α-fetoprotein (AFP) as a model, a new paper-based sandwich ELISA was developed. The linear range of the assay for AFP was from 0.1 ng/mL to 11.2 ng/mL, the detection limit was 0.04 ng/mL, and the recovery rate of AFP spiked into human serum sample ranged from 89.2% to 101.5%. The intra- and inter-assay coefficients of variations obtained were 4.6–7.1% and 5.8–10.3% for standard AFP, respectively. Compared with the conventional paper-based ELISA, the developed assay exhibited superiority in terms of sensitivity, lower detection limit, stability and reliability. This simple and sensitive paper-based sandwich ELISA holds promise in clinical applications. [ABSTRACT FROM AUTHOR]

Enormous disposal of paper wastes (PW) causing number of environmental problems. PW is efficiently used to extract multifunctional α-cellulose fibers (αCFs). Thus, αCFs extraction from PW, and functionalization with Fe 3 O 4 and chitosan were successfully performed for immobilization of laccase. Therefore, in this investigation, PW extracted αCFs were tuned with supermagnetic Fe 3 O 4 (M) and functionalized with chitosan (CTA) (M-PW-αCF-CTA). Furthermore, M-PW-αCF-CTA was glutaraldehyde cross-linked for covalent laccase immobilization. The synthesized materials were characterized by FT-IR, TGA, FE-SEM, FE-HR-TEM and VSM analyzes. M-PW-αCF-CTA exhibited magnetic saturation value of 14.72 emu/g. Laccase immobilized on M-PW-αCF-CTA (M-PW-αCF-CTA- Lac ) gave 92% of activity recovery and loading capacity of 73.30 mg/g. M-PW-αCF-CTA- Lac showed excellent pH, temperature, and storage stabilities with the exceptional reusability potential. Moreover, M-PW-αCF-CTA- Lac was applied for repeated removal of carcinogenic Direct Red 28 (DR28). Therefore, M-PW-αCF-CTA- Lac is green and economical biocatalyst with extraordinary separation potential can be enforced for environmental pollutants reclamation. [ABSTRACT FROM AUTHOR]

Hemoglobin A1c (HbA1c) is a standard biomarker to measure long-term average glucose concentration for diagnosis and monitoring of diabetes. Various methods have been reported for measuring HbA1c, however, portable and precise determination is still challenging. Herein, a new highly sensitive electrochemical nanobiosensor is developed for the specific determination of HbA1c. A nanocomposite of reduced graphene oxide (rGO) and gold with hierarchical architecture structure was electrochemically deposited on a cheap and flexible graphite sheet (GS) electrode. The nanocomposite increased the surface area, improved the electron transfer on the electrode surface and augmented the signal. It also provided a suitable substrate for linkage of thiolated DNA aptamer as a bioreceptor on the electrode surface by strong covalent bonding. The quantitative label free detection was carried out by differential pulse voltammetry (DPV) in a phosphate-buffered saline (PBS) solution containing redox probe Fe(CN) 6 3−/4-. The detection is based on insulating the surface in presence of HbA1c and decreasing the current, which is directly related to the HbA1c concentration. The nanobiosensor demonstrated high sensitivity of 269.2 μA. cm−2, wide linear range of 1 nM–13.83 μM with a low detection limit of 1 nM. The biosensor was successfully used for measuring HbA1c in blood real sample. Furthermore, it is promising to use it as a part of a point of care device for low-invasive screening and management of diabetes. Image 1 • An electrochemical nano-genosensor is proposed to hemoglobin A1c determination. • Graphite sheet (GS) is used as a cheap electrode and good candidate to commercialize. • A nanostructure of RGO-gold is electrodeposited on the GS by a facile method. • The biosensor exhibited a very high sensitivity for measuring HbA1c. • The developed biosensor is successfully used for HbA1c measurement in blood sample. [ABSTRACT FROM AUTHOR]

Highlights: [•] Graphene was covalently modified to have polycaprolactone brushes on the surface. [•] Functionalized graphene paper exhibited super-toughness and high flexibility. [•] Lithium ion battery anode fabricated from the paper showed excellent capacity. [Copyright &y& Elsevier]

Paper spray (PS) ionization, an ambient ionization method, has previously been explored as a direct and fast method for mass spectrometric analysis of complex mixtures. It has been applied to the analysis of a wide variety of compounds, mostly small molecules. The work reported here extends the application of PS ionization to noncovalent protein complexes on an ion mobility tandem mass spectrometer. Similar mass spectra for protein complexes were obtained by PS ionization and nanoflow electrospray ionization (nESI), indicating that intact protein complexes can be preserved in PS ionization. In addition, collisional cross sections measured by ion mobility provide evidence that the protein assemblies may remain compact by PS ionization. With PS, it is possible to detect hemoglobin tetramer from a blood sample with minimal sample preparation. This is the first report to show that PS ionization is a promising ionization method for nonconvalent protein complexes. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the multi-walled carbon nanotubes (MWCNTs)–cellulose paper as a chemical vapor sensor. Cellulose solution was prepared by dissolving cotton pulp in LiCl/N,N-dimethylacetamide solution. MWCNTs were covalently grafted to cellulose by reacting imidazolides–MWCNTs with cellulose solution. Using this product, the MWCNTs/cellulose (M/C) paper was fabricated, followed by mechanical stretching to align MWCNTs with cellulose chains. Characteristics of the M/C paper were analyzed in terms of scanning electron microscope images, Young''s modulus and electrical resistance. The M/C paper was investigated as a chemical sensor that can detect vaporized analyte molecules, such as, methanol, ethanol, 1-butanol and 1-propanol. Their electrical responses on the sensor were evaluated by not only comparing their relative resistance response (A R ) depending on the concentration, but also checking signal reversibility under cyclic exposure of each analyte. Due to sensitive and reversible expansion/contraction of the M/C paper in response to analytes, the M/C paper showed reversible and fast response with the following rank of A R : methanol

Tyrosinase is used to eliminate phenolic compounds from wastewater. Therefore, its immobilization is important to enhance catalytic efficiency. Papery materials are of particular interest for use as support for enzyme immobilization since the porous microstructure of fiber networks in papers can provide a suitable reaction environment, especially in flow-type catalytic reactions. However, immobilization of protein onto papery structure needs chemical modifications in severe conditions. To overcome this challenge, a cellulosic paper was directly amine-functionalized in moderate conditions and used for tyrosinase immobilization. The support was pretreated with HCl (0.5 N) solution and then sequentially immersed in ethylenediamine (EDA), glutaraldehyde solution (2% v/v) and the crude enzyme. In comparison with the untreated one, the immobilized enzyme on the EDA-treated support offered a 3.7-fold increase in activity. The FTIR spectra as well as EDX analysis proved the presence of amine groups in the cellulosic paper and also covalent immobilization of tyrosinase on the modified support. When considering the effect of pH on the activity at 25 °C, a maximum relative activity of 134% at pH 6 was revealed. Similarly, evaluating the effect of temperature on the activity at pH 7 displayed a maximum relative activity of 152% at 35 °C. The immobilized enzyme was suitable for use for more than four cycles to degrade a phenolic compound at severe pH and temperature conditions. Additionally, the immobilized enzyme was active after treatment of the surface at different pHs and temperatures for 105 min. The chemically modified cellulosic paper can be used as a support for enzyme immobilization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interface covalent bonding was developed for densely-packed paper cathodes. • High areal/volumetric capacities and mechanic flexibility have been synchronously acquired. • The intrinsic polysulfide adsorption/catalysis was demonstrated by experiments and DFT study. Lithium-sulfur batteries are promising candidates for powering flexible devices with high energy densities. To realize both high areal and volumetric capacity of lithium-sulfur batteries, while maintaining flexible and mechanically robust characteristics, is challenging for their portable energy storage applications. Herein, interface covalent bonding was demonstrated to design densely-packed graphene/CoS 2 /nano-sulfur hybrid papers with flexible and robust characteristics for energy-dense, compact and foldable lithium-sulfur batteries. The as-designed paper cathodes showed excellent cycling stability with a low decay rate of 0.044% per cycle over 800 cycles at 1 C, as well as high reversible areal capacity (4.11 mAh cm−2) and volumetric capacity (1240 Ah L−1). Meanwhile, the assembled batteries performed a high gravimetric/volumetric energy density (363.5 Wh kg−1/378 Wh L−1) under high sulfur loading (5.6 mg cm−2) and lean electrolyte/sulfur ratio (E/S: 5 μL mg−1). Furthermore, durable pouch cells based on as-designed integrated paper cathodes showed negligible performance decay even at a folding angle of 180°, highlighting their practical applications for flexible power systems. [ABSTRACT FROM AUTHOR]

The article describes chemical bleaches, which are powerful chemical agents that damage colour by breaking and reforming covalent bonds within organic colouring matter. Chromopore is a system of multiple bonds linked together in a conjugated system affecting the colour of organic compounds. The use of chlorine dioxide, an oxidising agent, in the conservation context, is said to be highly questionable due to health and safety issues.

Nanocrystalline cellulose (CNC) produced from waste paper by direct acid hydrolysis without any alkali or bleaching treatment was used to reinforce polyurethane elastomer (PU). By comparison, traditional cellulosic sources such as microcrystalline cellulose and waste cotton were also used to extract CNC and prepare polyurethane nanocomposites. The result showed that CNC extracted from waste paper had the largest aspect ratio, crystallinity and thermal stability. Three kinds of CNC all built interactions with polyurethane matrix through hydrogen bonds and covalent bonds. Amongst, polyurethane nanocomposites with CNC extracted from waste paper had the largest thermodynamic properties and stiffness. Briefly, CNC extracted from waste paper was comparable with CNC isolated from traditional cellulosic sources and could be used for stronger reinforcement of PU with lower cost. This work realized recycling of waste paper with a simple method and prepared a thermally resistant PU with low cost. [Display omitted] • Nanocrystalline cellulose was prepared with a simple method without any pretreatment. • Waste paper could be utilized for nanocrystalline cellulose production. • Nanocellulose from waste paper was comparable to that from traditional cellulosic source. • Realization of thermal modification of polyurethane by nanocellulose addition. • Economically heat resistant polyurethane from waste paper cellulose was achieved. [ABSTRACT FROM AUTHOR]

The binding mechanisms of two reactive sizing agents, alkenyl succinic anhydride (ASA) and maleated sunflower oil high-oleic (MSOHO), with cellulose were studied. While ASA is produced from olefins out of fossil resources, MSOHO is a green sizing agent based on renewable plant materials. In contrast to common assumptions, that ASA is mostly covalently bound to cellulose, this study showed the largest part of ASA to be bound only by physisorption and only a rather small fraction, typically about 0.5 %, to be covalently attached by ester bonds. In the case of MSOHO, the covalent binding was only slightly higher, with about 3 % of the total amount being covalently linked. In both cases, covalently bound sizing agents were found to be almost uniformly distributed over the whole DP range of the cellulose as seen by carboxyl-selective fluorescence labeling in combination with size exclusion chromatography ('FDAM method'). [ABSTRACT FROM AUTHOR]

With the introduction of carbon nanotubes, their fascinating features, including outstanding strength, exceptional stiffness, low density, and structural integrity at the nanoscale, became evident. These qualities generated excitement for a variety of technological applications. Over the last ten years, an evolving understanding of carbon nanotube mechanics has been shaped by a combination of experimental validation, the refutation of theoretical predictions, and the application of various computer simulation techniques. The objective of this research was to explore theoretical predictions concerning the visualization and manipulation of minute structures. The central focus is on examining mechanical characteristics, including Young's modulus, Poisson's ratio, shear modulus, and buckling criteria in diverse configurations of single-walled carbon nanotubes. Beam elements are utilized in this study to model the covalent bonds between Carbon-Carbon (C-C) atoms in Carbon Nanotubes (CNTs). Using a continuum mechanics framework, the paper aims to predict the characteristics of these beam elements. Baseline values for the properties of C-C bonds are established through numerical analysis to conduct simulations. The paper employs a finite element methodology to scrutinize the mechanical behavior of carbon nanotubes and carries out a parametric investigation to evaluate the influence of single-walled carbon nanotube diameter on shear modulus and buckling loads. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this article is to prepare graphene/polyimide composite materials for use as bearing cage materials, improving the friction and wear performance of bearing cages. Design/methodology/approach: The oil absorption and discharge tests were conducted to evaluate the oil content properties of the materials, while the mechanical properties were analyzed through cross-sectional morphology examination. Investigation into the tribological behavior and wear mechanisms encompassed characterization and analysis of wear trace morphology in PPI-based materials. Consequently, the influence of varied graphene nanoplatelets (GN) concentrations on the oil content, mechanical and tribological properties of PPI-based materials was elucidated. Findings: The composites exhibit excellent oil-containing properties due to the increased porosity of PPI-GN composites. The robust formation of covalent bonds between GN and PPI amplifies the adhesive potency of the PPI-GN composites, thereby inducing a substantial enhancement in impact strength. Notably, the PPI-GN composites showed enhanced lubrication properties compared to PPI, which was particularly evident at a GN content of 0.5 Wt.%, as evidenced by the minimization of the average coefficient of friction and the width of the abrasion marks. Practical implications: This paper includes implications for elucidating the wear mechanism of the polyimide composites under frictional wear conditions and then to guide the optimization of oil content and tribological properties of polyimide bearing cage materials. Originality/value: In this paper, homogeneously dispersed PPI-GN composites were effectively synthesized by introducing GN into a polyimide matrix through in situ polymerization, and the lubrication mechanism of the PPI composites was compared with that of the PPI-GN composites to illustrate the composites' superiority. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0415 [ABSTRACT FROM AUTHOR]

The objective of this paper is to describe a new data-driven framework for computational screening and discovery of a class of materials termed "metavalent" solids. "Metavalent" solids possess characteristics that are nominally associated with metallic and covalent bonding (in terms of conductivity and coordination numbers) but are distinctly different from both because they show anomalously large response properties and a unique bond-breaking mechanism that is not observed in either covalent or metallic solids. The paper introduces the use of Hirshfeld surface analysis to provide quantum level descriptors that can be used for rapid screening of crystallographic data to identify potentially new "metavalent" solids with novel and emergent properties. [ABSTRACT FROM AUTHOR]

Despite a bicentennial history, the interest in polyiodides and related systems still flourishes. The chemical puzzle provided by the intricate nature of chemical bonding in these polyanions remains challenging these days. The advent of the halogen bond and the spreading interest in supramolecular interactions of halogen-based systems promoted further recent interest. Research in the area of materials, where local bonding details eventually result in desired macroscopic properties, provided a further boost. Herein, we illustrate the consequences of contemplating a different bonding scheme for polyiodides, one making explicit use of electron-deficient multicenter bonds (EDMBs), an emerging concept in this area. We present a reinterpretation of polyiodide bonding using a revised approach to the Lewis dot formulas, leading to a clearer pen-and-paper understanding of their bonding. The model is general and can be applied to other related problems (here polyiodonium cations, and other homo- and hetero-polyhalides). Our alternative narrative has a few interesting consequences on several traditional and currently hot topics, including the nature of basic building blocks for polyiodides, hypervalency vs. hypercoordination, the distinction between covalent bonds and supramolecular interactions, and the nature of secondary and halogen bonds. [ABSTRACT FROM AUTHOR]

Fluoride ion is a strong Lewis base and one of the essential trace elements in human body. It plays a very important role in human health and ecological balance. The deficiency or excessive intake of fluoride ions will cause serious health problems, so the development of a sensitive and accurate detection method for fluoride ions is very important. The colorimetric and/or fluorescence sensing method has been a long standing attractive technique with high sensitivity and fast response. To date, most reported probes for fluoride ion are applicable only in organic solvents or organic-containing aqueous solutions. However, the probes for fluoride ion used in aqueous solution are more practically needed in view of environment protection and human health. In this paper, the materials and designing ideas of the colorimetric and/or fluorescent probes for fluoride ion based on different detection mechanisms in recent years were reviewed. Two main categories including formation of hydrogen bonds and formation of coordination covalent bonds were discussed. The latter one is further subdivided into three types, formation of B-F bond, formation of Si-F bond and formation of Mn+-F bond. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) are studied and used in various fields due to their high power density, fast charging/discharging rate, as well as long cycle life. Compared to other traditional electrode and electrolyte materials, supramolecular hydrogels have great advantages in the application of SCs due to their excellent properties. Unlike covalent bonds, supramolecular systems are assembled through dynamic reversible bonds, including host–guest interactions, ion interactions, electrostatic interactions, hydrogen bonding, coordination interactions, etc. The resulting supramolecular hydrogels show some special functions, such as stretching, compression, adhesion, self‐healing, stimulus responsiveness, etc., making them strong candidates for the next generation of energy storage devices. This paper reviews the representative progress of electrodes, electrolytes, and SCs based on supramolecular hydrogels. Besides, the properties of supramolecular hydrogels, such as conductivity, extensibility, compressibility and elasticity, self‐healing, frost resistance, adhesion, and flexibility, are also reviewed to highlight the key role of excellent properties of hydrogel materials in SCs. In addition, this article also discusses the challenges faced by current technologies, hoping to continue promoting future research in this field. [ABSTRACT FROM AUTHOR]

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In the current study, we introduce "click chemistry" as a powerful tool to tailor cyclodextrin–cellulose combination product followed by the inclusion of ciprofloxacin hydrochloride (CipHCl) as antibacterial agent. Initially, beta-cyclodextrin (β-CD) and cellulose fibers (CFs) were modified so as to be mono-6-propargylamino-6-deoxy-β-CD (Pro-β-CD) and azidated cellulose fibers (CFs-N3), respectively. Afterward, the "click reaction" was carried out between Pro-β-CD and CFs-N3 to fabricate a covalent grafting of β-CD onto CFs resulting in click product (CFs-N3@Pro-β-CD). The drug-delivery kinetics of the loaded CipHCl was performed by immersing samples into an aqueous solution, and the amount of adsorbed and released CipHCl was measured, as a function of time, by UV spectroscopy. Compared to original CFs, the load quantity of CipHCl into the click product was greatly increased, the release time of CipHCl from CFs-N3@Pro-β-CD was prolonged, and considerably higher antibacterial activity against E. coli and S. aureus was observed. The click product exhibited excellent antibacterial activity and sustained antibacterial efficacy up to 12 and 10 days against S. aureus and E. coli. The results showed that β-CD has been successfully grafted onto CFs via covalent bonds, while maintaining the intrinsic properties and the integrity of the fibers. Compared with the control paper sheet, the mechanical properties of the paper are well preserved. [ABSTRACT FROM AUTHOR]

The paper introduces Chemdex, a freely accessible web-based database of over 70 000 compounds characterised by crystallography from across the periodic table. Its software calculates for an atom of interest within each compound classifications including valence number, oxidation number, coordination number, electron number, several covalent bond classifications, and the attached atom set. Users may explore distributions of these classifications by percentages and heat map displays for individual elements or sets of elements, or in several cases for one classification plotted against a second. These properties often display clear periodicity. Based upon distributions across the periodic table of valence numbers, electron numbers, coordination numbers, and attached atom data suggestions are made regarding the placement of hydrogen in the periodic table, membership of group 3 in the periodic table, locations of the early actinoids in the periodic table, and assignments of certain elements as metalloids. [ABSTRACT FROM AUTHOR]

Paper, nanocellulose, and other polysaccharide-based materials can be excellent candidates for food packaging barrier layers, except that they tend to be vulnerable to moisture. This article reviews published research describing various chemical treatments having the potential to render hydrophobic character to such layers. Emphasis is placed on systems in which hydrophobic monomers are used to treat either particles or sheets comprised largely of polysaccharides. A goal of this review is to identify combinations of materials and procedures having promise for scale-up to industrial production, while providing effective resistance to moisture. The idea is to protect the underlying polysaccharide-based barrier layers such that they can continue to impede the transfer of such permeants as oxygen, greases, flavor compounds, and water vapor. A further goal is to minimize any adverse environmental impacts associated with the treatments. Based on the research articles considered in this review, promising hydrophobic treatments can be achieved involving silanes, ester formation, other covalent interactions, plasma treatments, and to some extent by various treatments that do not require formation of covalent bonds. The article is designed such that readers can skip ahead to items of particular interest to them. [ABSTRACT FROM AUTHOR]

Reductive elimination is a key step in Ni-catalysed cross-couplings, which is often considered to result in new covalent bonds. Due to the weak oxidizing ability of Ni(II) species, reductive eliminations from Ni(II) centers are challenging. A thorough mechanistic understanding of this process could inspire the rational design of Ni-catalysed coupling reactions. In this article, we give an overview of recent advances in the mechanistic study of reductive elimination from Ni(II) species achieved by our group. Three possible models for reductive elimination from Ni(II) species were investigated and discussed, including direct reductive elimination, electron density-controlled reductive elimination, and oxidation-induced reductive elimination. Notably, the direct reductive elimination from Ni(II) species often requires a high activation energy in some cases. In contrast, the electron density-controlled and oxidation-induced reductive elimination pathways can significantly enhance the driving force for reductive elimination, accelerating the formation of new covalent bonds. The intricate reaction mechanisms for each of these pathways are thoroughly discussed and systematically summarized in this paper. These computational studies showcase the characteristics of three models for reductive elimination from Ni(II) species, and we hope that it will spur the development of mechanistic studies of cross-coupling reactions. [ABSTRACT FROM AUTHOR]

Methyltrioxorhenium(VII) (MTO) is a widely employed catalyst for metathesis, olefination, and most importantly, oxidation reactions. It is often preferred to other oxometal complexes due to its stability in air and higher efficiency. The seminal papers of K. B. Sharpless showed that when pyridine derivatives are used as co-catalysts, MTO-catalyzed olefin epoxidation with H2O2 as oxidant, a particularly useful reaction, is accelerated, with pyridine speeding up catalytic turnover and increasing the lifetime of MTO under the reaction conditions. In this paper, combined experimental and theoretical results show that the occurrence of σ-hole interactions in catalytic systems extends to MTO. Four crystalline adducts between MTO and aliphatic and heteroaromatic bases are obtained, and their X-ray analyses display short Re⋯N/O contacts opposite to both O–Re and C–Re covalent bonds with geometries consistent with σ-hole interactions. Computational analyses support the attractive nature of these close contacts and confirm that their features are typical of σ-hole interactions. The understanding of the nature of Re⋯N/O interactions may help to optimize the ligand-acceleration effect of pyridine in the epoxidation of olefins under MTO catalysis. [ABSTRACT FROM AUTHOR]

This paper presents a computational procedure for the determination of the dynamic behaviour of graphene with different types of defects. The lattice of graphene is modelled using the molecular structural mechanics (MSM) approach, where the C–C covalent bonds are replaced by equivalent beam elements. Cantilever and bridged boundary conditions are applied for the analysis. Four types of Stone–Wales (SW) defects such as S-W (555-8), S-W (555-888-3), S-W (555-77-8) and S-W (888-3), and two types of pinhole defects with 6 and 24 elements eliminated are examined on armchair, zigzag and chiral type of graphene sheet. The effect of the structural length of the sheet, chirality and defect type on the vibrational properties of graphene sheets is investigated. The computed results reveal that SW defects produce a high frequency to that of pristine graphene, whereas the effect of pinhole defects is significant as compared to SW defects. The computed results will be useful in nano-resonator-based sensor applications. [ABSTRACT FROM AUTHOR]

3D printing is a versatile technology capable of rapidly fabricating intricate geometric structures and enhancing the performance of flexible devices in comparison to conventional fabrication methods. However, 3D-printed devices are susceptible to failure as a result of minuscule structural impairments, thereby impacting their overall durability. The utilization of self-healing, biodegradable materials in 3D printing holds immense potential for increasing the longevity and safety of devices, thereby expanding the application prospects for such devices. Nevertheless, enhancing the self-repairing capability of devices and refining the 3D printing performance of self-healing materials are still considerable challenges that need to be addressed to achieve optimal outcomes. This paper reviews recent developments in the field of advancements in 3D printing using self-healing and biodegradable materials. First, it investigates self-healing and biodegradable materials that are compatible with 3D printing techniques, discussing their printability, material properties, and factors that influence print quality. Then, it explores practical applications of self-healing and biodegradable 3D printing technology in depth. Finally, it critically offers practical perspectives on this topic. [ABSTRACT FROM AUTHOR]

According to Ruedenberg's classic treatise on the theory of chemical bonding [K. Ruedenberg, Rev. Mod. Phys. 34, 326–376 (1962)], orbital contraction is an integral consequence of covalent bonding. While the concept is clear, its quantification by quantum chemical calculations is not straightforward, except for the simplest of molecules, such as H2+ and H2. This paper proposes a new, yet simple, approach to the problem, utilizing the modified atomic orbital (MAO) method of Ehrhardt and Ahlrichs [Theor. Chim. Acta 68, 231 (1985)]. Through the use of MAOs, which are an atom-centered minimal basis formed from the molecular and atomic density operators, the wave functions of the species of interest are re-expanded, allowing the computation of the kinetic energy (and any other expectation value) of free and bonded fragments. Thus, it is possible to quantify the intra- and interfragment changes in kinetic energy, i.e., the effects of contraction. Computations are reported for a number of diatomic molecules H2, Li2, B2, C2, N2, O2, F2, CO, P2, and Cl2 and the polyatomics CH3–CH3, CH3–SiH3, CH3–OH, and C2H5–C2H5 (where the single bonds between the heavy atoms are studied) as well as dimers of He, Ne, Ar, and the archetypal ionic molecule NaCl. In all cases, it is found that the formation of a covalent bond is accompanied by an increase in the intra-fragment kinetic energy, an indication of orbital contraction and/or deformation. [ABSTRACT FROM AUTHOR]

1,2‐benzisothiazol‐3(2H)‐one derivatives are highly active against a broad spectrum of fungi as well as Gram positive and Gram negative bacteria. For this reason they are extensively used, for example, as additives in detergents, leather products, paper coatings, and antifouling paintings. In this paper experimental findings are reported proving that the sulfur atom of benzisothiazolinones have a remarkable tendency to form short and directional chalcogen bondings on the extension of the covalent N−S bond and, to a lesser extent, of the C−S bond. Analyses of the Cambridge Structural Database confirm the interaction as a primary recognition motif of these systems. The electrophilicity of sulfur is crucial in the chemical reactions initiating the cascade of events resulting in the biopharmacological activities of benzisothiazolinones. The reported results suggest that the electrophility of sulfur may play a role also at earlier stages than the reactive ones, namely it may pin the compounds at the active site of target enzymes via chalcogen bondings that preorganize the system in the conformation required for the bonds formation/cleavage determining the biopharmacological activity [ABSTRACT FROM AUTHOR]

Watson-Crick automata are belonging to the natural computing paradigm as these finite automata are working on strings representing DNA molecules. Watson-Crick automata have two reading heads, and in the 5' → 3' models these two heads start from the two extremes of the input. This is well motivated by the fact that DNA strands have 5' and 3' ends based on the fact which carbon atoms of the sugar group is used in the covalent bonds to continue the strand. However, in the two stranded DNA, the directions of the strands are opposite, so that, if an enzyme would read the strand it may read each strand in its 5' to 3' direction, which means physically opposite directions starting from the two extremes of the molecule. On the other hand, enzymes may not have inner states, thus those Watson-Crick automata which are stateless (i.e. have exactly one state) are more realistic from this point of view. In this paper these stateless 5' → 3' Watson-Crick automata are studied and some properties of the language classes accepted by their variants are proven. We show hierarchy results, and also a "pumping", i.e., iteration result for these languages that can be used to prove that some languages may not be in the class accepted by the class of stateless 5' → 3' Watson-Crick automata. [ABSTRACT FROM AUTHOR]

Chemical bonds, including covalent and ionic bonds, endow semiconductors with stable electronic configurations but also impose constraints on their synthesis and lattice-mismatched heteroepitaxy. Here, the unique multi-scale van der Waals (vdWs) interactions are explored in one-dimensional tellurium (Te) systems to overcome these restrictions, enabled by the vdWs bonds between Te atomic chains and the spontaneous misfit relaxation at quasi-vdWs interfaces. Wafer-scale Te vdWs nanomeshes composed of self-welding Te nanowires are laterally vapor grown on arbitrary surfaces at a low temperature of 100 °C, bringing greater integration freedoms for enhanced device functionality and broad applicability. The prepared Te vdWs nanomeshes can be patterned at the microscale and exhibit high field-effect hole mobility of 145 cm2/Vs, ultrafast photoresponse below 3 μs in paper-based infrared photodetectors, as well as controllable electronic structure in mixed-dimensional heterojunctions. All these device metrics of Te vdWs nanomesh electronics are promising to meet emerging technological demands. The limited scalability of 1D semiconductors has restricted their large-area optoelectronic applications so far. Here, the authors report the low-temperature synthesis of wafer-scale van der Waals nanomeshes composed of self-welding Te nanowires on various substrates, showing improved transport and photoelectric properties. [ABSTRACT FROM AUTHOR]

Certain naturally occurring volatile organic compounds are able to mitigate food spoilage caused by microbial growth. Their considerable vapor pressure enables them to create an antimicrobial atmosphere within a package, and this property can be used for the development of active food-packaging technologies. The volatility of these molecules, however, makes their stabilization difficult and limits their effectiveness. Whilst much research is being undertaken on the use of natural antimicrobial volatiles for inhibiting microbial growth in food, less attention has been paid to the design of controlled-release mechanisms that permit the efficient application of these compounds. Most studies to date either spray the volatile directly onto the fresh product, immerse it in a solution containing the volatile, or embed the volatile in a paper disc to create a vapor in the headspace of a package. More sophisticated alternatives would be delivery systems for the sustained release of volatiles into the package headspace. Such systems are based on the encapsulation of a volatile in organic or inorganic matrices (cyclodextrins, electrospun non-wovens, polymer films, micelles, molecular frameworks, etc.). However, most of these devices lack an efficient triggering mechanism for the release of the volatile; most are activated by humidity. All of these techniques are revised in the present work, and the most recent and innovative methods for entrapping and releasing volatiles based on reversible covalent bonds are also discussed. [ABSTRACT FROM AUTHOR]

This paper developed a method for preparing ultrasound-responsive microgels based on reversible addition fragmentation chain transfer-hetero Diels–Alder (RAFT-HAD) dynamic covalent bonding. First, a styrene cross-linked network was successfully prepared by a Diels–Alder (DA) reaction between phosphoryl dithioester and furan using double-ended diethoxyphosphoryl dithiocarbonate (BDEPDF) for RAFT reagent-mediated styrene (St) polymerization, with a double-ended dienophile linker and copolymer of furfuryl methacrylate (FMA) and St as the dienophile. Subsequently, the microgel system was constructed by the HDA reaction between phosphoryl disulfide and furan groups using the copolymer of polyethylene glycol monomethyl ether acrylate (OEGMA) and FMA as the dienophore building block and hydrophilic segment and the polystyrene pro-dienophile linker as the cross-linker and hydrophobic segment. The number of furans in the dienophile chain and the length of the dienophile linker were regulated by RAFT polymerization to investigate the effects of the single-molecule chain functional group degree, furan/dithioester ratio, and hydrophobic cross-linker length on the microgel system. The prepared microgels can achieve the reversible transformation of materials under force responsiveness, and their preparation steps are simple and adaptive to various potential applications in biomedical materials and adaptive electrical materials. [ABSTRACT FROM AUTHOR]

In recent years, MnFePGe magnetocaloric materials have been widely studied as promising candidates for magnetic refrigeration materials. The Curie temperature of MnFePGe can be adjusted to around room temperature by changing the element ratio or doping with other elements. Due to its first-order magnetic and structural transition, it engenders a large entropy change but unfortunately also exhibits a large thermal hysteresis during the phase transition, which leads to energy loss and lower refrigeration capability. In this paper, we establish a correlation between the in-plane covalent bonding and Curie temperature (TC), thermal hysteresis (ΔThys), two-phase coexistence zone (ΔTcoex), and entropy change (ΔSDSC) using 54 Mn2−xFexPyGe1−yMz (where M is a metallic or nonmetallic doped element) samples with different components. Neutron diffraction and XRD diffraction data and refinements have been employed to allow a detailed electron density reconstruction of six typical samples with the maximum entropy method. We find that the length of the in-plane bonding is closely correlated with the TC and ΔThys, while the TC, ΔThys, ΔTcoex, and ΔSDSC have no significant correlation with the length of the interlayer covalent bond. Moreover, we find that the ΔThys correlates most strongly with the change in the bond length when undergoing the paramagnetic-to-ferromagnetic phase transition rather than the absolute value of the bond length. These results provide an understanding of how to control the properties, enabling effective ways to tune the composition of magnetic refrigeration materials to tailor magnetocaloric properties for optimal performance. [ABSTRACT FROM AUTHOR]

The difficult recycling and degradation in cured epoxy resins can be solved by introducing dynamic covalent bonds. However, the introduction of dynamic bonds degrades the properties of epoxy resins. In this paper, the dual‐cured epoxy resin with high mechanical properties and high healing efficiency were obtained by constructing interpenetrating networks (IPNs). The effect of IPNs on the recyclability of epoxy resins was investigated. The performance is as follows, the flexural and tensile strengths is 89 and 54.2 MPa, respectively, and the breakdown strength is 32.5 kV/mm. In addition, the recyclability and high healing efficiency of the dual‐cured epoxy resin were verified, and the effect of the hot‐pressing temperature and time on the properties of the recycled samples were investigated. Under certain hot‐pressing conditions, the flexural and tensile strengths of the recycled samples were recovered to 95.06% and 85.28%, respectively, and the breakdown strength was recovered to 83.6%. [ABSTRACT FROM AUTHOR]

In this paper, we reported a facile approach for the preparation of benzo[c][1,2]oxazine scaffolds via visible light induced phenyl iodine bis(trifluoroacetate) (PIFA) oxidative [4+2] annulation of vinyl benzenes with N‐aryl substituted hydroxamic acids. In the transformation, amidoxyl radicals are readily generated via covalent I−O bond formation and photo‐induced I−O cleavage from N‐aryl substituted hydroxamic acids, and their coupling with vinyl arenes in the form of [4+2] annulation delivers benzo[c]‐[1,2]oxazines derivatives. This reaction proceeds in the absence of transition metals and catalysts, exhibiting broad substrate scope of both alkenes and N‐aryl substituted hydroxamic acids. [ABSTRACT FROM AUTHOR]

This paper employs first-principles calculations to comprehensively investigate the structural, dynamic, electronic, mechanical, and optical properties of A 2 BH 6 (A = K, Rb; B Ge, Sn) perovskite hydrides. Mechanical, thermodynamic, and dynamic stabilities are confirmed through calculations of elastic constants, formation energies, and phonon dispersion. The B/G ratio, below 1.75, indicates a brittle nature and a preference for covalent bonding. Electronic property analysis reveals that these hydrides are indirect band gap semiconductors with band gap values of 1.897 eV, 2.468 eV, 2.129 eV, and 2.657 eV, respectively. Optical property studies demonstrate high ultraviolet absorption. A key focus of this study is the gravimetric hydrogen storage capacities, which are found to be 3.84 wt% for K 2 GeH 6 , 2.97 wt% for K 2 SnH 6 , 2.48 wt% for Rb 2 GeH 6 , and 2.09 wt% for Rb 2 SnH 6. These findings not only enrich the research on the physical properties of perovskite hydrides but also provide an important theoretical basis and new options for the development of efficient hydrogen storage materials. The crystal structure, hydrogen storage capacity and band gap value of A 2 BH 6 (A = K, Rb; B Ge, Sn). [Display omitted] • A 2 BH 6 (A = K,Rb; B Ge,Sn) perovskite has been investigated using first-principles. • A 2 BH 6 (A = K, Rb; B Ge, Sn) exhibits thermodynamic, mechanical and dynamical stability. • A 2 BH 6 (A = K, Rb; B Ge, Sn) is a medium width indirect band gap semiconductor. • A 2 BH 6 (A = K, Rb; B Ge, Sn) has a hydrogen storage capacity of 2.09 W% to 3.84 W%. • The desorption temperature is found to be 221.1 K for K 2 SnH 6. [ABSTRACT FROM AUTHOR]

Over the past few decades, polymers with dynamic covalent bonds have received a lot of attention due to their self‐healing, shape memory, and environmental adaptation properties. However, most of them require a change in catalyst or environmental conditions to achieve bond reduction and exchange reactions, and the harsh conditions are not conducive to the practical application of the material. However, the dr‐polyurea based polyurethane (PUU) can be prepared at low temperatures, and can be worn and rebuilt in a catalyst free and mild environment, thus showing excellent self‐healing function. In this paper, the unique dynamic reaction mechanism of hindered urea bond (HUB), the properties of related polymers and the development of frontier are reviewed. In addition, the performance research of HUB and the application prospect of innovative synthetic PUU are also reviewed. [ABSTRACT FROM AUTHOR]

: The construction of composite flooding system based on dynamic covalent bonds is one of the effective methods to improve the salt and temperature resistance of polymer flooding agents. The polymers used in most composite systems are xanthan gum and guar gum. In this paper, a novel multi‐hydroxyl polymer was synthesized, and a new composite system was constructed based on the dynamic boronic ester bonds. Firstly, the multi‐hydroxyl polymer P(AM‐DPMOH2) was prepared by aqueous solution copolymerization of acrylamide (AM) and a dihydroxy monomer 2,3‐dihydroxy‐N‐(3‐methacrylamidopropyl)‐N,N‐dimethylpropan‐1‐aminium (DPMOH2), which was obtained by quaternization reaction between 3‐chloro‐1,2‐propanediol and N‐(3‐dimethylaminopropyl). Then, the composite system was prepared by the P(AM‐DPMOH2) solution and polyboronic acid compound (BPEI). The effects of DPMOH2 content in P(AM‐DPMOH2), molecular weight of P(AM‐DPMOH2), molecular weight of BPEI, phenylboronic acid groups content in BPEI and pH on the formation of thickening composite system were investigated. The results showed that when the content of DPMOH2 in P(AM‐DPMOH2) exceeded 40 wt%, viscosity average molecular weight of P(AM‐DPMOH2) was higher than 5.0×105 g/mol, the molecular weight of PEI in BPEI was larger than 3000 g/mol, the content of phenylboronic acid groups in BPEI was more than 39.3 %, and pH was in the range of 8–9, the thickening composite system can be formed by P(AM‐DPMOH2) and BPEI. In addition, both the temperature and salt resistance of the composite system formed by 3000 mg/L P(AM‐DPMOH2) and 2000 mg/L BPEI was much better than that of 3000 mg/L P(AM‐DPMOH2). The results of this paper provide a new finding of how to construct a composite flooding system with dynamic covalent bonds. [ABSTRACT FROM AUTHOR]

Macroalgae with nontoxicity, biodegradability and biocompatibility has attracted more attentions as a sustainable alternative towards petroleum-derived plastics. However, brittleness and high affinity towards water has limited marine-based macroalgae films to be widely used. Thus, this paper aims to compare the roles of calcium chloride as ionic cross-linker and acrylic resin as covalent cross-linker in agar-PEG plasticised biofilm composite. Agar biofilm composite with PEG 1000 40% were cross-linked with i) calcium chloride 1, 2, 3 and 4 (CaCl2/agar) wt/wt % at 2 or 4 min immersion time, and ii) acrylic resin at 10, 20, 30, 40 and 50 (acrylic resin/agar) wt/wt %. FTIR and TGA proved that CaCl2 and acrylic resin managed to cross-link agar-PEG films ionically and covalently respectively. In general, films cross-linked with CaCl2 produced highest affinity towards water than films cross-linked with acrylic resin. Highest tensile strength, highest tensile modulus and lowest elongation at break was achieved when films cross-linked with CaCl2. Films cross-linked with CaCl2 has higher degradation rate than films cross-linked with acrylic resin. In conclusion, different mode of cross-linking (ionic or covalent) imparted different properties on the agar-PEG film. [ABSTRACT FROM AUTHOR]

Starch is affected by several limitations, e.g., retro-gradation, high viscosity even at low concentrations, handling issues, poor freeze–thaw stability, low process tolerance, and gel opacity. In this context, physical, chemical, and enzymatic methods have been investigated for addressing such limitations or adding new attributes. Thus, the creation of biomaterial-based nanoparticles has sparked curiosity. Because of that, single nucleotide polymorphisms are gaining a lot of interest in food packaging technology. This is due to their ability to increase the mechanical and water vapor resistance of the matrix, as well as hide its re-crystallization during storage in high-humidity atmospheres and enhance the mechanical properties of films when binding in paper machines and paper coating. In medicine, single nucleotide polymorphisms (SNPs) are suitable as carriers in the field of drug delivery for immobilized bioactive or therapeutic agents, as well as wastewater treatments as an alternative to expensive activated carbons. Starch nanoparticle preparations can be performed by hydrolysis via acid hydrolysis of the amorphous part of a starch molecule, the use of enzymes such as pullulanase or isoamylase, or a combination of two regeneration and mechanical treatments with the employment of extrusion, irradiation, ultrasound, or precipitation. The possibility of obtaining cheap and easy-to-use methods for starch and starch derivative nanoparticles is of fundamental importance. Nano-precipitation and ultra-sonication are rather simple and reliable methods for nanoparticle production. The process involves the addition of a diluted starch solution into a non-solvent, and ultra-sonication aims to reduce the size by breaking the covalent bonds in polymeric material due to intense shear forces or mechanical effects associated with the collapsing of micro-bubbles by sound waves. The current study focuses on starch nanoparticle manufacturing, characterization, and emerging applications. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs)/epoxy composites are composed of CNTs, epoxy resin, and the interphase between them. The micro-morphology of the interphase has a significant influence on the macro-properties of composites, which is mainly attributed to the difference in the interaction between CNTs and epoxy resin. However, a systematic research on the interaction between CNTs and epoxy resin on composite properties is still insufficient. In this paper, the surface properties of three types of functionalized CNTs, the adhesion forces between the typical functional groups and epoxy groups, as well as the curing characteristics and the thermal properties of the CNTs/epoxy composites were investigated by using experimental methods like surface energy analysis, atomic force microscopy, and differential scanning calorimetry. This paper performed direct measurements on the interaction between CNTs with functional groups and epoxy resin. Moreover, it provided several experimental evidences for the mechanism of interfacial interaction affecting thermal properties of CNTs/epoxy composites. It indicated that it is conducive to form covalent bonds at the CNTs/epoxy composite interface when there is a strong interaction between CNTs and epoxy resin, and the thermal property could be improved finally. [ABSTRACT FROM AUTHOR]

Highlights As is known, to establish covalent or non‐covalent interaction between filler and matrix, which helps to reduce the interface thermal resistance (ITR) as well as construct good thermal conduction channels, is a good strategy for dealing with the risk of thermal runaway in the extreme service environment of electronic equipment. In this paper, carboxylated nanocellulose fiber (c‐CNF) was used as matrix, and a hybrid filler (M‐CoNPs@GNP) was fabricated by coating cobalt‐nanoparticles (CoNPs) and grafting maleimide on graphene nanosheets (GNPs). M‐CoNPs@GNP/c‐CNF thermally conductive composite (TCC) films were successfully fabricated by combining with c‐CNF. As zero‐dimensional particles, CoNPs can effectively prevent GNPs agglomeration due to surface effects, and “‐NH” in maleimide dehydrates with “‐COOH” in c‐CNF to form “C‐N‐C” covalent bonds, with strong hydrogen bond formed between filler and matrix, which remarkably enhances the interface compatibility between matrix and filler. The ITR has been reduced to form a well‐defined three‐dimensional thermal conduction path, achieving an ultra‐high in‐plane TC (35.9 W·m−1·K−1) for MCGC40, which is 7.9 times that of pure c‐CNF film, in addition to a sufficiently high tensile strength of 123.3 MPa. The combination of high in‐plane TC, excellent mechanical flexibility and good electrical insulation jointly justifies the potential application of M‐CoNPs@GNP/c‐CNF TCC films in effective thermal management of flexible electronic products. CoNPs effectively inhibit GNPs agglomeration. GNPs exhibit hydrophilicity after modification. Modified fillers interact fairly well with the matrix. High tensile strength and exceptional flexibility are achieved. TCC films exhibit both electrical insulation and hydrophobicity. [ABSTRACT FROM AUTHOR]

In the natural environment, plastics and microplastics (MPs) are difficult to break down due to their hydrophobicity, the presence of persistent covalent bonds, and their functional groups' resistance to attack. The destiny of both organic and inorganic pollutants at contaminated areas can be influenced by MPs ability to absorb them. Because of their enormous surface to volume ratio and chemical surface characteristics, MPs are able to absorb dangerous substances from their surroundings. Accordingly, the study's main objectives were to provide a concise review of characterization techniques of MP biodegradation techniques, including the nano‐enabled methods, and the gaps in current research were outlined. This review paper summarizes the degradation mechanism and efficiency of MPs in different circumstances. For the purpose of eliminating plastic pollution, this work will help for the further studies. [ABSTRACT FROM AUTHOR]

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Sulfur‐polyacrylonitrile (SPAN) is a sulfur‐based active material for next‐generation lithium‐sulfur battery cathodes. Due to the covalent bonding between sulfur chains and the polymeric backbone, the shuttle effect degrading classical sulfur‐based cathodes can be suppressed while also achieving a high active material content in the cathode. In this paper, we investigate the processability of an industrially scalable SPAN active material with 38 wt.‐% of sulfur in a water‐based and scalable process route. The potential of the SPAN material for industrial adoption and the impact of the process route on the cell performance are discussed. We show that when processed correctly, the SPAN material delivers exceptional cycling stability and good C‐rate performance with ether‐based electrolytes. However, the performance of the SPAN cathode is influenced by the mixing characteristic. Using higher mixing intensities during the slurry preparation leads to deterioration of the electrochemical performance. This can be attributed to a decreasing carbon black percolation with increasing tip speed in combination with the kinetic limitation of sulfur cathodes during Li2S2 and Li2S oxidation. [ABSTRACT FROM AUTHOR]