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A simple approach was developed to fabricate high‐performance MXene/cellulose (MC)‐based electromagnetic interference (EMI) shielding papers. The oriented MXene sheets located on one side of cellulose filter paper construct a continuous conductive layer, endowing the MC paper with high electrical conductivity (240.1 S/m) and excellent EMI shielding effectiveness (29.3 dB for 0.192‐mm thickness) at an MXene content of 0.72 vol%. Moreover, the EMI shielding effectiveness of four stacked MC papers reached 40.5 dB. This result means that 99.9911% of the microwave radiation is attenuated, and 0.0089% is transmitted, through the four‐piece MXene/cellulose filter papers. Therefore, MC paper has promising properties for excellent EMI shielding materials in current electronic devices. [ABSTRACT FROM AUTHOR]

The application of traditional cellulosic paper is limited because of its flammability, so it is necessary to explore new materials that can be used in the field of flame‐retardant paper. Based on the synergistic effect between fibers, flame‐retardant lyocell (FRL) and calcium alginate (FRL/Ca‐Alg) composite paper is prepared by a simple but efficient method. The thermal degradation process of the composite paper is analyzed by thermogravimetric (TG) and TG analysis coupled with Fourier transform infrared, the flame retardancy of the composite paper is analyzed by vertical flammability (VF) tests, limiting oxygen index test and cone calorimetry test, and the morphology of the residue after VF tests is observed by scanning electron microscopy. It is found that, the Ca‐Alg releases a large amount of CO2 before ignited, which delayed the ignited time of the composite paper; FRL reduces the effective combustion heat of composite paper during combustion, and the compact char formed by FRL effectively inhibits the smoldering of Ca‐Alg in the end stage of combustion. Based on these, the synergistic flame‐retardant effect of composite paper is proposed. [ABSTRACT FROM AUTHOR]

Reported herein is an economical, plastic‐ and fluorine‐free coating approach for oil and water repellent paper substrates using blends of poly(vinyl alcohol) and chitosan‐graft‐polydimethylsiloxane copolymer. The obtained coated paper showed good water‐resistance, as evidenced by its low Cobb60 values of ~20 ± 2.1 g/m2 and high water contact angles of 119 ± 6.3 °. The kit rating of the coated paper was 7.6/12, indicating decent grease‐resistant properties as compared to the kit value of 0/12 for the uncoated paper. The coated paper is also repulpable as demonstrated by the complete washing off the coating from the coated paper. Giving the cost‐effective nature of the coating materials and good water and oil‐resistant properties of the coated paper, the approach developed here is commercially viable, and will offer a multitude of environmental benefits such as the elimination of microplastic‐ and PFAS problems associated with existing paper coatings. [ABSTRACT FROM AUTHOR]

Although styrene acrylate emulsions (SAE) have demonstrated promising applications as surface sizing agents for paper, their strengthening effect on pulp fibers in papermaking is not clear. In this study, bagasse fibers, an agricultural waste, were treated with SAE to study the influences on the mechanical properties of the produced papers. SAE copolymers with hard chain (H‐PSA) and soft chain (S‐PSA) were prepared and added to bagasse pulp slurry at concentrations of 1%–4% by weight. The findings indicated that for the soft and hard copolymers, the glass transition temperatures were 19.5 and 26.8°C and their emulsion particle sizes were 166 and 182 nm, respectively. The copolymers strengthened the produced paper by wrapping around and forming a network of chemical and physical bonds with the pulp fibers. Papers treated with 3% H‐PSA exhibited the optimum improvement in tensile strength (38 MPa) and breaking length (67 m) by 13% and 64%, respectively. Treated papers were negatively affected by UV radiation due to phenyl groups spread along the chains. The copolymers demonstrated good wet‐strength properties achieved by self‐ and co‐crosslinked networks. The prepared paper sheets showed a preference for the mechanical properties of treated samples over the untreated ones. [ABSTRACT FROM AUTHOR]

Acid‐catalyzed hydrolysis of glycosidic bonds is the most important degradation mechanism affecting cellulose‐based materials. It results in the decrease of DP and in the loss of the original mechanical properties. The neutralization of acidity is therefore one of the most efficient ways to hamper the degradation of cellulosic artworks. However, in the case of acidic and strongly degraded artifacts, in addition to deacidification, a consolidation treatment must be performed. To this aim, a new class of biopolymers, obtained by a synthetic procedure that considers the principles of Sustainable Chemistry, was investigated. Three allyl saccharide/vinyl acetate copolymers, having different molar ratios between starting monomers, were prepared using α,α'‐trehalose, and used to synthesize the corresponding allyl saccharide/vinyl alcohol copolymers. The use of saccharide derivatives as monomers improves the affinity and compatibility of the biopolymer with the artifacts to be treated. After characterization, the efficacy of the copolymers in the strengthening of degraded paper was evaluated with mechanical tests. The most effective system was thus selected for further testing. Its performance was compared to that of Klucel G®, a commercial product belonging to the class of cellulose derivatives, which are largely used in conservation practice. [ABSTRACT FROM AUTHOR]

Meeting the current needs for easier, more precise and faster analyses that also follow the principles of green analytical chemistry requires novel analytical chemistry strategies. Since the appearance in this century of the first device based on a paper platform, many studies have been presented in the literature, providing a wide range of designs and possibilities for the application of paper platforms to electroanalytical systems. This Review gives an overview of the field and can pave the way for the future development of electrochemical paper‐based analytical devices. We also present a critical point of view regarding what has been investigated and developed and what is still missing. This Review discusses the efforts made in the field related to important topics such as the choice of the paper substrate, the device construction process, the characterization of the device, and applications in different areas. In this way, we indicate some steps necessary for optimizing the design of the devices, with a focus on multidisciplinary collaborations that could move entire systems from the bench of the laboratory to the field. More than just a notepad: An overview of electrochemical paper‐based analytical devices, which could pave the way for future developments in the field. A critical point of view is presented regarding what has been investigated and developed as well as what is still missing. Some steps necessary for optimizing the design of the devices are indicated, with a focus on multidisciplinary collaborations that could move entire systems from the bench of the laboratory to the field. [ABSTRACT FROM AUTHOR]

ABSTRACT To improve the paper properties of the poly(1,3,4-oxadiazoles) (POD), the POD pulps were prepared by prechemical and mechanical methods to increase their polarity, contact area, and interaction. The fibrillated degree of the staple fibers was evaluated by the Canadian Standard Freeness and the specific surface area, while the surface free energy was calculated by the Micro-wilhelmy method. Meanwhile, the functional groups and compositions on the surface of the POD fibers were confirmed by the FTIR-ATR and the X-ray photoelectron spectroscopy, and the surface morphological structure and the crystalline structure of the POD fibers were observed by the fiber analyzer, scanning electron microscope, and Wide-angle X-ray diffraction, respectively. It was found that the pronounced abrasive and distinctive grooves were formed on the surface of the POD fibers after prechemical and mechanical treatment. The surface free energy of POD fibers increased 8.41%, and the polar part increased by 32.10% after treatment. It was confirmed that the polar functional groups and fibril were formed after chemical and mechanical treatment, so the interaction of the POD fibers was highly enhanced, and as a result the apparent density, tensile strength, fold endurance, and tear strength of the paper formed by those treated fibers were all improved apparently. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39818. [ABSTRACT FROM AUTHOR]

ABSTRACT Waterborne UV-curable polyurethane (UWPU) dispersions with different hydrophilicity and functionalities were prepared by varying the content of dimethylol butanoic acid (DMBA) and pentaerythritol triacrylate (PETA). And linear and cyclic chain extenders with different functionalities were also incorporated into the UWPU backbone, including isophorone diamine (IPDA), diethylene triamine (DETA), and ethylene diamine (EDA). Effects of DMBA content, PETA content, photoinitiator content, UV curing time, chain extender on the properties of UWPU dispersions and films, as well as the properties of the unsized and sized paper were investigated. The water resistance and mechanical properties of sized paper were greatly relied on the particle size, the molecular weight, the croslinking density, and penetrability of UWPU. UWPU dispersion chain extended with IPDA (IPDA-UWPU) displayed smaller particle size than that of UWPU. The paper sized with IPDA-UWPU was endowed with best water resistance, tensile strength, folding strength and surface strength. XPS depth analysis revealed that IPDA-UWPU exhibited better penetrability into the paper substrate than UWPU. SEM and AFM demonstrated that the smoothness of sized paper was improved, and the bond strength between fibers was enhanced. The obtained UWPU could be directly used as an effective and fast drying surface sizing agent for cellulose fiber paper. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42354. [ABSTRACT FROM AUTHOR]

ABSTRACT Cationic polyacrylamide with different molecular weights were used to preflocculate the lime mud (LM) before it was added to the paper stock for handsheet preparation. The particle sizes, ζ potential, and morphology of the unpreflocculated and resulting preflocculated LM were studied. We found that high-molecular-weight cationic polyacrylamide (H-CPAM) led to larger LM flocs with a more positive ζ potential. The scanning electron microscopy images indicated that the morphological structure of the filler hardly changed during the preflocculation process. The effects of the preflocculation on the filler retention and paper properties were also investigated. The results show that the handsheets filled with preflocculated LM had better hydrophobicity and strength properties compared to handsheets filled with unpreflocculated LM, especially for H-CPAM-preflocculated LM. The paper formation was also improved, and the optical properties nearly remained the same. In addition, the LM preflocculated with H-CPAM had the highest filler retention. At a filler loading of 30%, the filler retention of the H-CPAM-preflocculated LM was higher than 86; it was less than 82.5% in other cases. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41640. [ABSTRACT FROM AUTHOR]

All‐cellulose composites (ACCs) were prepared by partially dissolving cellulose in the filter paper using NaOH/thiourea aqueous solution. The effects of dissolution time, thiourea ratio, and temperature on the properties of ACCs were investigated. ACCs were characterized by scanning electron microscope, attenuated total reflectance Fourier transform infrared spectroscopy, Raman spectroscopy, X‐ray diffraction, and tensile tests. The results revealed that the fibers in ACCs were tightly intertwined. The crystalline form of cellulose in ACCs was transformed from type I to type I/II mixture, and the crystallinity decreased from 77.32 to 51.40%. The tensile strength of ACCs was remarkably improved to 23.16 MPa. The results confirmed ACCs had a high potential for practical applications in the packaging field. [ABSTRACT FROM AUTHOR]

ABSTRACT Antimicrobial polyethylene wax (PEW) emulsions, prepared by emulsifying polyethylene wax grafted with polyhexamethylene guanidine hydrochloride (PEW-g-PHGH), were used as wet-end additives or coating materials for fabricating hydrophobic and anti-mold hand-sheets or paper. To obtain PEW-g-PHGH, maleic anhydride (MAH) was adopted as a bridging agent. The melt or solution grafting of MAH to PEW was performed to achieve the appropriate grafting degree and grafting efficiency. The resulting PEW-g-PHGH was emulsified using a homogenizer by means of surfactants, and the resulted emulsions were characterized in terms of particle size, zeta potential, charge density, minimal inhibitory concentration (MIC), and adsorption capacity. After that the hydrophobicity of emulsion treated hand-sheets was determined by measuring water contact angle (WCA). The morphology of the hand-sheets treated by the emulsion was revealed using scanning electron microscope (SEM) and atom force microscope (AFM). Finally, the antimicrobial properties of the emulsion treated hand-sheets were investigated by anti-mold tests against Aspergillus niger and Chaetomium globosum. Results indicated that the PEW-g-PHGH emulsions exhibited good stability, high fiber adsorption capacity, and antimicrobial activity. The WCAs of the treated hand-sheets reached 82°-140° with 80%∼99.9% growth inhibition against fungi. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42214. [ABSTRACT FROM AUTHOR]

The Cover Feature illustrates the use of electrochemical paper‐based analytical devices (ePADs); the image focuses on the possible coupling of the electrode with smartphones to perform in situ analysis in different fields. This Review focuses on several aspects that are required to prepare an efficient ePAD, such as paper choice and characterization, device construction, applications, and the difficulties that still need to be surpassed. More information can be found in the Review by W. J. Paschoalino et al. on page 10 in Issue 1, 2019 (DOI: 10.1002/celc.201800677). [ABSTRACT FROM AUTHOR]

OLEDWorks has started production operations for manufacturing OLED lighting panels. Compared to OLED displays, affordability is much more important for market adoption of OLED lighting. To this end, we have developed a unique approach in both product design and manufacturing processes. These elements are embodied in our first product, amber lighting for the health care market. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are a significant source of environmental pollution, posing threats to human safety. With growing concerns about environmental degradation, catalytic oxidation technology emerges as a paramount and widely adopted approach for VOC elimination, renowned for its operational simplicity, energy efficiency, and environmental friendliness. As a representative transition metal catalyst, cobalt‐based catalysts have garnered widespread use in VOC catalytic oxidation due to their cost‐effectiveness, versatility, and distinctive physicochemical properties. This paper provides a detailed exposition of the construction strategies and structure‐activity relationship of Co3O4‐based catalysts in VOCs oxidation reaction, encompassing both monometallic Co3O4 and multimetallic cobalt‐based catalysts. Furthermore, it offers a comprehensive summary and discussion of the latest research progress concerning Co3O4‐based catalysts in practical applications. Concluding with a meticulous analysis, the paper addresses the technical challenges inherent in developing Co3O4‐based catalysts for VOCs degradation. Additionally, it proposes research directions aimed at overcoming these challenges, contributing to the ongoing discourse on environmental sustainability. [ABSTRACT FROM AUTHOR]

Organic electrode materials (OEMs) are emerging green power because of the promising advantages such as environmental friendliness, abundant sources, easy recycling, and structural diversity. However, several inherent issues, including low electronic conductivity, dissolution of active materials, and particle pulverization restrict their practical application. MXene, as a novel 2D material has exhibited enormous potential to solve the issues of OEMs due to its high conductivity, unique structure, exceptional mechanical property, and abundant surface groups. Up to now, various effective strategies have been presented and achieved positive effects, such as constructing heterojunction structures, in situ assembly, dip-coating, preparing freestanding MXene paper, etc. Nonetheless, comprehensive review of the progress and status is rare. Herein, an overview of the application of MXene in organic electrode materials for rechargeable batteries is systematically put forward. Meanwhile, recent progress and future development directions are presented. This review can serve as a guide for future research. [ABSTRACT FROM AUTHOR]

The shortage of fresh water in the world has brought upon a serious crisis to human health and economic development. Solar‐driven interfacial photothermal conversion water evaporation including evaporating seawater, lake water, or river water has been recognized as an environmentally friendly process for obtaining clean water in a low‐cost way. However, water transport is restricted by itself by solar energy absorption capacity's limits, especially for finite evaporation rates and insufficient working life. Therefore, it is important to seek photothermal conversion materials that can efficiently absorb solar energy and reasonably design solar‐driven interfacial photothermal conversion water evaporation devices. This paper reviews the research progress of carbon‐based photothermal conversion materials and the mechanism for solar‐driven interfacial photothermal conversion water evaporation, as well as the summary of the design and development of the devices. Based on the research progress and achievements of photothermal conversion materials and devices in the fields of seawater desalination and photothermal electric energy generation in recent years, the challenges and opportunities faced by carbon‐based photothermal conversion materials and devices are discussed. The prospect of the practical application of solar‐driven interfacial photothermal conversion evaporation technology is foreseen, and theoretical guidance is provided for the further development of this technology. [ABSTRACT FROM AUTHOR]

This paper presents a new approach for characterizing heat sealing processes in packaging machines, which identifies all appropriate and optimum sealing parameters subject to given quality criteria. The presented approach is distinct from established methods, such as heat seal curves or response surface plots, in three aspects: It provides an easy‐to‐read chart indicating optimum and appropriate settings of sealing temperature and dwell time, as well as process robustness for each parameter set. The data points of the charts are generated directly from experiments without using any regression model. The design of experiments features a determinate sequence of tests and no iterative loops are necessary. The approach stems from a 'trade‐off' model of heat sealing and a specific multi‐objective optimization method. This trade‐off model states that improving seam quality, reducing sealing temperature, reducing dwell time, and increasing process robustness are conflicting objectives. This hypothesis is deduced from a literature review and verified by experiments. The optimization method claims that all optimum sealing parameters are part of the solution of a multi‐objective optimization problem, the Pareto‐frontier. This hypothesis is elaborated into a design of experiments using the normal‐boundary‐intersection method, and is verified using a peelable seam and tear seam scenario. [ABSTRACT FROM AUTHOR]

Cement is known to be brittle and usually reinforced with fibers. However, there is a lack of effective chemical bonding between organic fibers and inorganic cement, resulting in a weaker interfacial bonding strength. In this paper, amino hyperbranched polymer (HBP) was used to modify the surface of polyacrylonitrile (PAN) fibers, and then silica nanoparticles (SiO2 NPs) were grafted on the surface of modified PAN fibers to realize the inorganic treatment of organic fibers. The modified PAN fibers applied to cement concrete can significantly enhance the interfacial strength between the fibers and cement. The morphology and chemical composition of the modified PAN fibers were characterized by scanning electron microscope, atomic force microscope, electron energy dispersive spectroscopy, and Fourier transform infrared spectroscopy, and the influence of grafting conditions on grafting effect was analyzed. The results show that SiO2 NPs were evenly distributed on the surface of PAN fiber. When SiO2 NPs concentration was 4%, grafting temperature was 50°C, and grafting time was 4 h, the grafting degree of SiO2 NPs grafted PAN fiber can reach to 1.4%. After coating with SiO2 NPs, the pullout bonding strength of the PAN fiber was increased from 5.5 to 6.5 cN. [ABSTRACT FROM AUTHOR]

Diamond materials at different nanoscales provide them various characteristics such as elastic mechanical properties in needle‐like nanotips, flexibility of 2D films having atomic thicknesses and constant hardness under high pressures, superior field electron emission properties of vertically wall‐like composites, unprecedented hardness and improved toughness of nanotwin diamond (nt‐diamond), while the inherent excellent properties of bulk diamond (e.g., high Young's modulus, robustness, biocompatibility) can be maintained. In this paper, the newly born 1D diamond nanothreads, 2D diamanes, as well as 3D nt‐diamond are briefly reviewed. The innovations, progresses and achievements of different dimensional diamond nanostructures, covering lines, planes and volumes are overviewed. The topical problems and future outlooks of diamond nanostructures are outlined and discussed. [ABSTRACT FROM AUTHOR]

The proposed paper presents the design of a leaky‐wave antenna inspired by holographic metasurfaces employing thin film. Leveraging the holographic principle, this metasurface showcases its transformative capacity by converting an omnidirectionally radiating monopole into a highly directional antenna emitting leaky waves. The holographic metasurface is constructed using a thin film of polyimide (PI) (Df = 0.008; Dk = 3.5), measuring 50 μm in thickness. The antenna structure comprises multiple layers, commencing with the top PI layer, succeeded by a 40 μm thick adhesive layer (Df = 0.004; Dk = 6). Subsequent layer includes the Rogers RT/duroid 5880 substrate (Df = 0.0009; Dk = 2.20), grounded at the bottom and has a thickness of 1.6 mm. The meticulously tailored design of the proposed antenna ensures optimal performance at 15 GHz, facilitating directional radiation and precise beam steering at 10 degrees (ϴ = 10°). This innovative design, incorporating the holographic metasurface on thin film, significantly enhances the antenna's performance, increasing gain from 1.5 dBi to 13.8 dBi. [ABSTRACT FROM AUTHOR]

This paper delves to improve the upper‐limit temperature of hydrogenated nitrile rubber (HNBR) through regulation of the vulcanization process, filler system and cross‐linking additive. The tensile test and scanning electron microscope images showed that the aging at 180°C significantly accelerated the deterioration in the property of HNBR compared with 150°C aging. The results showed that a higher dosage of bis(1‐(tert‐butylperoxy)‐1‐methylethyl)‐benzene curing agent reduced the compression set of HNBR without sacrificing its tensile strength. Carbon black N539‐filled HNBR exhibited high tensile strength, while carbon black N774‐filled HNBR showed high heat resistance and low compression set. When the HNBR sample was reinforced with 20 phr of N539 and 20 phr of N774 carbon black, it achieved low compression set, high tensile strength, and heat resistance simultaneously. Then, N,N′‐bismaleimide‐4,4′‐diphenylmethane (BMI) was introduced into the HNBR composite as a cross‐linking assistant agent. The residual strength of BMI‐modified HNBR was 20.3 MPa (the retention rate of 92.3%), and its compression set was as low as 19.2% after aging at 180°C for 72 h. Even after aging the composite at 180°C for 168 h, its strength retention rate remained at 83.2% (18.3 MPa). The approach provided here increased the upper‐limit temperature range of HNBR to 180°C. [ABSTRACT FROM AUTHOR]

In this paper, wound dressing materials made of silk fibroin (SF) and transgenic SF with Arg-Gly-Asp motifs (TG-RGD SF) were developed. Initially, an animal evaluation experiment with mice to demonstrate the usefulness of SF film as a wound dressing was performed. The amorphous SF film was shown to promote the formation of granulation tissue and neovessels in the dermis, leading to skin regeneration. As a result, amorphous SF film is suitable for use as a wound dressing materials. Then, the SF- Human umbilical vein endothelial cells signaling pathway was determined by cell proliferation assay with pharmacological inhibitors. Subsequently, a mice evaluation experiment to assess the promotion of healing effects using TG-RGD SF was conducted and the results were compared with those obtained using SF. In the wound area evaluation and the quantitative evaluation of granulation tissue formation, the TG-RGD SF film promoted dermis regeneration more than the SF film. [ABSTRACT FROM AUTHOR]

A greedy randomized adaptive search procedure (GRASP) is a metaheuristic for combinatorial optimization. It is a multi-start or iterative process, in which each GRASP iteration consists of two phases, a construction phase, in which a feasible solution is produced, and a local search phase, in which a local optimum in the neighborhood of the constructed solution is sought. Since 1989, numerous papers on the basic aspects of GRASP, as well as enhancements to the basic metaheuristic, have appeared in the literature. GRASP has been applied to a wide range of combinatorial optimization problems, ranging from scheduling and routing to drawing and turbine balancing. This is the second of two papers with an annotated bibliography of the GRASP literature from 1989 to 2008. In the companion paper, algorithmic aspects of GRASP are surveyed. In this paper, we cover the literature where GRASP is applied to scheduling, routing, logic, partitioning, location, graph theory, assignment, manufacturing, transportation, telecommunications, biology and related fields, automatic drawing, power systems, and VLSI design. [ABSTRACT FROM AUTHOR]

Carbon‐reinforced polymer matrix composites (PMCs) have been thoroughly applied in different fields because of their benefits, such as low specific gravity, corrosion resistance, good electrical conductivity, and robust mechanical properties. Especially, with the emergence of fused deposition modeling (FDM) technology has further promoted the application of such materials in complex structural components. Recently, FDM printing carbon‐reinforced PMCs have become a hot topic in composites research, and many promising results have been achieved around related research. In order to help readers have a comprehensive and systematic understanding of the latest research progress of FDM printing carbon‐reinforced PMCs in terms of material modification, processing, material properties, and application levels, this paper reviews the properties and processes of FDM printed carbon‐reinforced PMCs and their potential applications in aerospace, flexible sensing, electrochemistry, and biomedical fields. The effects of commonly used carbon reinforcing materials on the performance of FDM printed PMCs were contrasted and analyzed. Moreover, the process optimization of printing carbon‐reinforced PMCs was introduced and highlighted. Finally, the current challenges and future research directions of FDM printing carbon‐reinforced PMCs were analyzed and prospected. [ABSTRACT FROM AUTHOR]

The conventional filtration loss reducers, which help reduce the invasion into the formation, often make the rheology of the oil‐based drilling fluid difficult to control. In this paper, the new type of porous deformable polymeric particle was synthesized as filtration loss reducer (FLR), through dispersion polymerization using acrylamide and stearyl methacrylate. Fourier transform infrared spectroscopy, differential scanning calorimeter, thermogravimetric analysis, contact angle apparatus, nitrogen adsorption/desorption techniques and scanning electron microscope have been carried out to confirm the chemical structure of the FLR. The results illustrated that FLR is a hydrophobic porous solid particle with deformability. The oil‐based drilling fluid loaded with FLR retains high temperature resistance up to 180°C and the density of 2.2 g/cm3. The FLR help reduced the filtration loss to 3.2 mL, smaller than their counterparts, and synthesized FLR has small impact on the rheology of drilling fluids. [ABSTRACT FROM AUTHOR]

The internet of things (IoT) is advancing human lives by providing various intelligent services. The advancement of cutting‐edge technologies necessitates an increase in the need for cyber security. In this light, an extensive research has been conducted to address IoT security concerns. However, several security challenges must be addressed before IoT can be utilized to its full potential in real‐time. Motivated by this fact, this study presents a novel integration approach of Natural Language Processing (NLP) with IoT systems to enhance its security. It investigates the current state of NLP and its applications. The key contribution of this paper is the development of a system for identifying malicious behaviors in an IoT environment using n‐gram and word‐embedding techniques. Several security challenges and possible future directions to enhance IoT security using NLP are also addressed in this study. [ABSTRACT FROM AUTHOR]

A large number of problems involve making decisions in an uncertain environment and, hence, with unknown outcomes. Optimization models aimed at controlling the trade‐off between risk and return in finance have been widely studied since the seminal work by Markowitz in 1952. In financial applications, shortfall or quantile risk measures are receiving ever‐increasing attention. Conditional value‐at‐risk (CVaR) is arguably the most popular of such measures. In the last decades, optimization models aimed at controlling risk have been applied to several application domains different from financial optimization. This survey provides an overview of the main contributions where CVaR is incorporated into an optimization approach and applied to a context different from financial engineering. The literature is classified following an application‐oriented perspective. The applications cover classical areas studied in operational research—such as supply chain management, scheduling, and networks—and less classical areas such as energy and medicine. For each area, concise paper excerpts are provided that convey the main ideas of the problems studied, and analyze how the CVaR has been used to cope with different sources of uncertainty. Finally, some open research directions are outlined. [ABSTRACT FROM AUTHOR]

Growing concerns about the harmful impact of synthetic polymers on the environment and living organisms have shifted the attention towards biopolymers which are environment‐friendly and biocompatible. Biopolymers represent attractive sustainable and biodegradable alternatives for replacing commercial synthetic polymers. Chitosan is one of the most prevalent biopolymers available on Earth. Chitosan is an alkaline cationic polymer, the deacetylated form of chitin. Chitosan possesses excellent physicochemical properties such as biocompatibility, biodegradability, nontoxic, nonallergenic, and biologically active molecules. During recent years, there has been a surge in the demand for chitosan in various fields, however, due to poor water solubility and mechanical properties, chitosan applications are limited to some extent. Strong inter and intramolecular hydrogen bonds in the chitosan matrix make it highly crystalline, reducing its water solubility. Chemical modification of the chitosan matrix by various technologies is reported to improve its solubility and other physicochemical characteristics, expanding the application areas. Details on various chemical reactions involved in chemical modification and other available technologies have been focused in this paper. The role of chitin deacetylase enzyme in chitosan modification has been discussed. This review aims to provide insight into recent developments in chitosan functionalization, and the development of chitosan derivatives for various applications. [ABSTRACT FROM AUTHOR]

In recent years, the packaging industry has utilized electronic packaging materials with epoxy resin (EP) and high‐performance fillers, exhibiting superior mechanical properties and thermal conductivity. Spherical silica micro‐powder (SSP) is a critical thermal conductive filler but faces challenges due to its inorganic nature. Surface modification is essential to improve SSP's compatibility and dispersion in organic matrices for effective use in EP‐based composites. In this paper, the effects of the following four modification methods on SSP/EP composites were studied: (1) the processes include co‐modification with dimethyldimethoxysilane (DMDMS) and trimethylethoxysilane (MTES), (2) modification with NaOH, (3) co‐modification with DMDMS and MTES in an alkaline environment after NaOH modification, and (4) co‐modification with methyltrimethoxysilane (MTMS) and propyltrimethoxysilane (PTMOS). Through comprehensive characterization and evaluation, it is evident that modification schemes 1, 3, and 4 significantly enhance SSP's hydrophobicity, dispersibility, and compatibility with EP. This led to the improvement of thermal conductivity and stability of the composite, and modification scheme 4 showed the highest enhancement, with a 42.6% increase in thermal conductivity. Moreover, the mechanical properties of modified composite materials, such as bending strength, impact resistance, and tensile strength, surpass those of unmodified SSP/EP composite materials. The study provides valuable insights for reducing manufacturing costs and enhancing productivity in the electronic packaging sector. [ABSTRACT FROM AUTHOR]

Shrinking resources of fossil oil prompt search for other biosphere‐present substrates to obtain polyols, which in turn are basic components to synthesize polyurethane foams (PUF). Widely available examples are biopolymers like starch, cellulose, and chitosan. It has been shown that oligomeric chitosan as well as water soluble chitosan can be applied to obtain polyols and rigid PUF of good performance properties. In this paper, the higher molecular mass chitosans, insoluble in organic solvents and water, were converted to polyols and ultimately into foamed polyurethane plastics. The polyols were characterized by the infrared spectra (IR), 1H‐NMR, and MALDI‐ToF methods. Their properties, such as density, viscosity, surface tension and hydroxyl numbers, were determined. The PUF were obtained from these polyols of various molecular mass. The biodegradable, rigid PUF of enhanced thermal resistance were obtained. Their physical parameters like apparent density, water volume absorption, dimension stability, heat conductance, compressive strength, and heat resistance at 150 and 175°C were studied and compared with those synthesized previously from oligomeric chitosan and water soluble chitosan. [ABSTRACT FROM AUTHOR]

Recent advances in the synthesis and applications of raspberry ketone are reviewed in this paper. Different routes to this material including chemical and biotechnological synthetic methods and extraction from natural sources are compared, and the applications of the ketone in flavour and fragrance, pharmaceuticals and in food and tobacco processing are discussed. Synthesis from petrochemical raw materials has the advantages of ready availability of ingredients and well‐understood synthetic steps, but direct synthesis from petrochemicals will eventually be replaced because of low yields and hazardous results to environment. The ketone can be made from natural raw materials, and the methods are promising if their disadvantages such as limited availability and complex, multi‐step reactions and harsh reaction conditions can be overcome. Biotechnological preparation methods have the advantages of reaction specificity, mild reaction conditions, but are limited in applicability because of complications associated with their synthetic and purification procedures at present. With the development of biotechnology, biotechnological preparation methods of the ketone may be the most important route in the future. Direct extraction of the ketone from natural raw materials is possible, but the cost is very high. From the view of syntheses and applications, the research perspectives of raspberry ketone are outlined in the end of this paper, which are the development of green and effective synthetic methods for raspberry ketone from natural raw materials and the preparation and application of raspberry ketone by biotechnological preparation methods. [ABSTRACT FROM AUTHOR]

Japan's fine ceramics (advanced ceramics) industry, which reached US$30 billion of production in 2018 (an annual growth rate of 6.3%), accounts for 40% of the global market. The mission of the Japan Fine Ceramics Association (JFCA), which consists of 116 corporate members related to fine ceramics, is to further promote the development of this industry. In this paper, we describe the recent trends of fine ceramics industry and the latest JFCA's activities, including the publication of the FC Roadmap 2050 (2021 edition). This roadmap addresses fine ceramics technologies and products that will meet increasingly diverse needs of society, market, and industry in the year 2050. [ABSTRACT FROM AUTHOR]

The T7 system is an orthogonal transcription‐system, which is characterized by simplicity, higher efficiency, and higher processivity, and it is used for protein or mRNA synthesis in various biological‐systems. In comparison with prokaryotes, the construction of the T7 expression system is still on‐going in eukaryotes, but it shows greatly applicable prospects. In the present paper, development of T7 expression system construction in eukaryotes is reviewed, including its construction in animal (mammalian cells, trypanosomatid protozoa, Xenopus oocytes, zebrafish), plant, and microorganism and its application in vaccine production and gene therapy. In addition, the innate challenges of T7 expression system construction in eukaryote and its potential application in vaccine production and gene therapy are discussed. [ABSTRACT FROM AUTHOR]

Alumina‐spinel castable has excellent refractory properties, including high volume and thermal stability, good hot strength, and excellent resistance against corrosion, erosion, and thermal spalling. Excellent refractory properties have made it a preferred lining for steel ladles, reducing the erosion and corrosion of molten metal and slag and improving the ladle life and efficiency for decades. These castables are also significant for the replacement of chrome‐bearing refractories that cause several health hazards. The current review paper covers preformed and in situ spinel containing alumina castables. It focuses on the importance of these castables in the sidewall and bottom portion of the steel ladle in detail, the effect of spinel and MgO content, and the factors affecting castable properties. The review also covers the final properties of castable and the application areas of alumina‐spinel castable in steel ladle, purging plugs, and RH‐degasser. [ABSTRACT FROM AUTHOR]

This special issue of the Journal Mathematical Methods in the Applied Sciences on the topic of Modelling, Analysis, and Applications is devoted to the development of mathematical modelling, analysis, and applications, from theoretical and numerical perspectives, involving different applied sciences and engineering. It collects invited contributions, from selected quality full papers submitted to the International Conference on Mathematical Analysis and Applications in Science and Engineering (ICMA2SC2022). The conference took place in Porto, Portugal in 27–29 June 2022 (https://www.isep.ipp.pt/Page/ViewPage/ICMASC). [ABSTRACT FROM AUTHOR]

This paper reports recent advancements in chitosan‐based antimicrobial biomaterials that aim to address the issue of antimicrobial resistance (AMR). Today, AMR is one of the most significant public health challenges the world is facing. To combat the overuse of antibiotics, a range of materials, including advanced nanosized polymers, have been explored as potential antimicrobial agents. In this direction, chitosan scores highly because of its unique combination of properties such as biodegradability, biocompatibility, bioactivity, non‐toxic, and, most importantly, its intrinsic antibacterial and antifungal activity. Herein, an overview of chitosan and its derivatives as potential alternatives to conventional antimicrobial therapeutics is reported. This review starts with understanding the AMR mechanism, which is critical for developing suitable materials for treating infectious diseases. Then, the inherent characteristics, modes of antimicrobial action, and factors that impact the antimicrobial effectiveness of chitosan and its derivatives are discussed. The authors further summarize various clinical trial results of chitosan‐based materials as antimicrobial agents. Finally, various antimicrobial applications of chitosan‐based materials are reported. In summary, this review offers new insights into the design of chitosan‐based sustainable materials for various antimicrobial applications. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) thin films (PVATFs) have recently exhibited different applications in various fields, such as biomedical, optical, and energy storage. One of their outstanding applications has been known as sensor devices for various physical parameters, such as pH, pressure, gas, chemicals, strain, and humidity measurements. In this paper, after a brief review of the PVATFs biomedical, optical, and energy applications, their role as sensors is discussed in more detail. Afterward, the main preparation methods of the PVATFs sensors, for example, spin and dip coating, chemical bath deposition, and electrodeposition are surveyed. Eventually, the characterization methods of the fabricated PVATF sensors, along with their optimization techniques have been presented. Highlights: Various applications of polyvinyl alcohol thin films (PVATFs) are presented.One of their main applications as sensor devices is discussed in more detail.PVATF sensors fabrication, characterization, and optimization are surveyed. [ABSTRACT FROM AUTHOR]

Aquatic foods are nutritious, enjoyable, and highly favored by consumers. In recent years, young consumers have shown a preference for prefabricated food due to its convenience, nutritional value, safety, and increasing market share. However, aquatic foods are prone to microbial spoilage due to their high moisture content, protein content, and unsaturated fatty acids. Furthermore, traditional processing methods of aquatic foods can lead to issues such as protein denaturation, lipid peroxidation, and other food safety and nutritional health problems. Therefore, there is a growing interest in exploring new technologies that can achieve a balance between antimicrobial efficiency and food quality. This review examines the mechanisms of cold plasma, high-pressure processing, photodynamic inactivation, pulsed electric field treatment, and ultraviolet irradiation. It also summarizes the research progress in nonthermal physical field technologies and their application combined with other technologies in prefabricated aquatic food. Additionally, the review discusses the current trends and developments in the field of prefabricated aquatic foods. The aim of this paper is to provide a theoretical basis for the development of new technologies and their implementation in the industrial production of prefabricated aquatic food. [ABSTRACT FROM AUTHOR]

The "all in one" multifunctional and concentrated daily chemical products are required by the market, such as the long‐term release of anti‐bacterial, medical, or perfume agents. These functions mainly rely on the microcapsules, which could encapsulate these functional and unstable molecules, and then release them in the long term. To stabilize these functional solid particles in a high‐content surfactant, it is necessary to add a suspending rheological modifier. The poly(acrylic acid) (PAA)‐based rheology modifier is one of the most common additives in the industry of daily chemicals, for thickening or suspending. In this paper, linear PAA, and branched PAA polymers (Carbomer 941 and Carbomer 940) were selected to study the suspending ability of PAA‐based rheology modifier in high‐content surfactant and to investigate the effect of PAA polymer structure and Mw on the complex solution's rheological properties. The yield and viscosity test of the complex solutions of linear PAA and high‐content surfactant revealed that the addition of linear PAA could lead to lower yield stress and viscosity, and failed to suspend the polystyrene (PS) model microspheres due to its smaller mean square radius of gyration. The branched PAA polymer, Carbomer 940 and Carbomer 941 were more stable than the linear PAA in these two kinds of surfactant. More specifically, Carbomer 940 with a higher Mw, would exhibit higher yield stress and viscosity than Carbomer 941 with a lower Mw in nonionic surfactant alcohol polyoxyethylene ether (AEO) solvent with content less than 5 wt%. When the content was higher than 5 wt%, Carbomer 941 presented higher yield stress and viscosity than Carbomer 940, and successfully suspended PS microspheres in the 20 wt% AEO solution. This could depend on the polymer chain's elongation state of these two PAA‐based branched rheology modifiers. The same trend happened in the appearance of Carbomer 940 and Carbomer 941 in alcohol ether sulphate (AES) solution. However, the electrostatic repulsive force between the AES and PAA‐based rheology modifier could further make the polymer chain curl up and restrain the suspending ability in a lower content surfactant solution. Therefore, this fundamental research could guide the application of the anionic polyelectrolytes in the concentrated daily chemical product for stable suspending particles. [ABSTRACT FROM AUTHOR]

The recycling of petroleum‐based polymers such as polypropylene (PP) and polyethylene (PE) is an effective means of reducing environmental pollution. However, the incompatible PP and PE blended waste is difficult to separate accurately, which reduces the quality of the recycled material. In this paper, the trifunctional acrylate monomer (trimethylolpropane triacrylate), peroxide (2,5‐dimethyl‐92,5‐di[tert‐butylperoxy] hexane) and free radical activity modifier (zinc dimethyldithiocarbamate) were applied to in situ generate the copolymer of isotactic polypropylene and high‐density polyethylene (iPP‐co‐HDPE) with a long‐chain co‐branched structure via a melt blending method. The co‐crystallization of the branched copolymer chain segments with the chemical identical homopolymers vastly improved the compatibility of iPP and HDPE components. This in situ co‐branching compatibility strategy resulted in a significant improvement in the mechanical properties of PE and PP mixed wastes. The temperature gradient extraction method was used to separate the co‐branching modified iPP/HDPE blends. The results confirm that the separated iPP‐co‐HDPE components have a highly co‐branched structure. The significant improvement in compatibility resulted in a large increase in elongation at break and impact strength of the iPP/HDPE blends, which provides an economic and effective method for the recycling of mixed PE and PP wastes. [ABSTRACT FROM AUTHOR]

Internet of things (IoT) applications called SmartApps are event‐driven programs running on the SmartThings cloud. To understand the behaviour of SmartApps, users may have questions regarding which execution flows follow particular events or why specific actions occur. However, checking internal programme behaviours, such as event‐driven execution flows, is more difficult for users because SmartApps run on the cloud. In this paper, we propose SmartProvenance, which is a provenance system for IoT applications and provides a graphical user interface (GUI) environment for provenance queries on event flow graphs. The event flow graph of a SmartApp visualises all execution control flows initiated by events, which are constructed by performing static programme analysis. The graph is decorated with dynamically collected event and action information in the GUI interface for provenance queries. Then, users can query the provenance by simply clicking on the graph. An event flow graph as the form of a GUI for queries in the SmartProvenance system allows users to view IoT services by all possible event flow paths in a SmartApp. Thus, the provenance information being visualised on the event flow graph can be intuitively understood in the context of IoT services. Therefore, users can answer provenance questions themselves without difficulty. [ABSTRACT FROM AUTHOR]

In this paper, we present a definition of the generalized fractional local derivative, which contains as a particular case several of those reported in the literature. In this framework, we apply this operator to the study of the solutions of some fractional differential equations and we focus mainly on a Gompertz model applied to the study of tuberculosis in Mexico. We also show the effectiveness of this model by fitting it to real data and by comparing it with other models using other well‐known definitions of fractional derivative. [ABSTRACT FROM AUTHOR]

The bottleneck problem of the development of high‐voltage motors to a larger capacity can be solved if the thermal conductivity is improved without sacrificing the insulation characteristics of the main insulation material. In this paper, a spraying technology based on electrospinning is proposed that can evenly spray boron nitride (BN) with high thermal conductivity onto the surface of mica tape. With the increase in BN content, the insulation and thermal conductivity of mica tape are optimized to varying degrees. When the BN content reaches 2.25 wt%, the in‐plane conductivity increases from 1.6 to 2.7 w/(m K), while the out‐of‐plane conductivity increases from 0.17 to 0.26 w/(m K). Additionally, the direct‐current (DC) breakdown strength has increased from 90.6 to 96.9 kV/mm and the dielectric constant and dielectric loss are almost unchanged. Finally, through simulation verification, if the modified mica tape is applied to the main insulation of a synchronous motor, the operating temperature of the motor insulation will be reduced from 73.5 to 66.1°C. This study provides a new research idea for the preparation of high thermal conductivity insulating materials. [ABSTRACT FROM AUTHOR]

The aim of this paper is to systematically review the evidence to explore whether smartphone applications that use self-regulatory strategies are beneficial for weight loss in overweight and obese adults over the age of 18 years. Sixteen electronic databases were searched for articles published up to April 2015 including MEDLINE, OVID, Ingenta, PSYCARTICLES and PSYCINFO, CINAHL, Sportdiscus, Science Direct, Web of Knowledge, Cochrane Library, JSTOR, EBSCO, Proquest, Wiley and Google Scholar. Twenty nine eligible studies were retrieved of which six studies met the inclusion criteria. Studies that recruited participants under the age of 18 years, adults with a chronic condition or did not report weight loss outcomes were excluded. Study findings were combined using a narrative synthesis. Overall, evidence suggests that smartphone applications may be a useful tool for self-regulating diet for weight loss as participants in the smartphone application group in all studies lost at least some bodyweight. However, when compared to other self-monitoring methods, there was no significant difference in the amount of weight lost. Findings should be interpreted with caution based on the design of the studies and the comparator groups used. Future research needs to be more methodologically rigorous and incorporate measures of whether eating habits become healthier in addition to measuring weight and BMI. [ABSTRACT FROM AUTHOR]

The journal Archaeometry and its first co-editor Martin Aitken played key roles in the development of archaeomagnetism. This paper briefly reviews all papers published in Archaeometry , and a few others, dealing with archaeomagnetic secular variation, archaeomagnetic dating, archaeointensity studies and related applications of magnetic studies to archaeology, to indicate some of the major developments over the past 50 years. [ABSTRACT FROM AUTHOR]

The search for materials with better performance, longer service life, lower environmental impact, and lower overall cost is at the forefront of polymer science and material engineering. This has led to the development of self‐healing polymers with a range of healing mechanisms including capsular‐based, vascular, and intrinsic self‐healing polymers. The development of self‐healable systems has been inspired by the healing of biological systems such as skin wound healing and broken bone reconstruction. The goal of using self‐healing polymers in various applications is to extend the service life of polymers without the need for replacement or human intervention especially in restricted access areas such as underwater/underground piping where inspection, intervention, and maintenance are very difficult. Through an industrial and scholarly lens, this paper provides: a) an overview of self‐healing polymers; b) classification of different self‐healing polymers and polymer‐based composites; c) mechanical, thermal, and electrical analysis characterization; d) applications in coating, composites, and electronics; e) modeling and simulation; and f) recent development in the past 20 years. This review highlights the importance of healable polymers for an economically and environmentally sustainable future, the most recent advances in the field, and current limitations in fabrication, manufacturing, and performance. [ABSTRACT FROM AUTHOR]

A novel nanocomposite leather‐finishing agent (denoted as H‐TiO2@SDS‐rGO/F‐PBMA) composed of fluorinated copolymer (denoted as F‐PBMA) matrix using methyl methacrylate (abbreviated as MMA), butyl acrylate (abbreviated as BA) as well as acrylic acid (abbreviated as AA) as monomers and H‐TiO2@SDS‐rGO composite nanoparticles as nano‐additives were successfully fabricated by aqueous emulsion polymerization in this paper. The hollow TiO2 nanoparticles (denoted as H‐TiO2) were firstly prepared with tetrabutyl titanate as titanium source wall and tetraethyl silicate as silicon source core through an alkali etching method, and then they were compounded with reduced graphene oxide (rGO) modified by sodium dodecyl sulfate (denoted as SDS‐rGO) for obtaining H‐TiO2@SDS‐rGO composite nanoparticles. Fourier transform infrared spectra, X‐ray diffraction, Raman spectra, scanning electron microscopy, and nuclear magnetic resonance spectra were used to characterize the structure and morphology of different samples. The experimental results reveal that the nanocomposite leather‐finishing agent not only has excellent transparency, but also endows sheepskin better weather resistance, thermal stability, hydrophobicity and mechanical properties compared with traditional leather finishing agents. [ABSTRACT FROM AUTHOR]

Polyoxymethylene (POM), as an energy‐saving material, is widely applied in the manufacturing field. Yet, research on the rectangular clinching process between metal and POM sheets is still lacking. In this paper, the rectangular clinching process for POM and Al5052‐H32 plates was investigated. The feasibility of the metal–polymer hybrid component had been analyzed in terms of diverse forming forces and diverse joint layout angles, respectively. The mechanical characteristics were appraised by the lap‐shear test. The failure modes of rectangular clinched joints produced under diverse forming conditions had also been analyzed. The results showed that the optimal forming force of rectangular clinched joints was 14 kN, in which the lap‐shear strength was 1090 N. Furthermore, the rectangular clinched joints produced under the joint layout angle of 90° could withstand the maximum lap‐shear load (1415 N) under the optimal forming force. The failure mode was the separation of two plates and the fracture of the bridge structures. [ABSTRACT FROM AUTHOR]

According to the infrared stealth mechanism, controlling the surface temperature of objects can effectively hide the infrared radiation and resist the infrared detection. In this paper, a high infrared transparent polymer ultrahigh molecular weight polyethylene (UHMWPE) is selected as the matrix of a thermal insulation material. UHMWPE porous films with high porosity and hybrid pore structure are obtained through the thermal induced phase separation combining with particle leaching method. The film structures with micropores and macropores are adjusted through the variation of the mass ratio of UHMWPE/liquid paraffin, the dosage and the particle size of NaCl. The thermal conductivity of the UHMWPE film is as low as 0.034 W/(m K), while the density is only 54.4 mg/cm3. The classical Maxwell‐Eucken model is used to discuss the relationship between the pore structure and the thermal conductivity of the films. It is determined that the hybrid porous structure can reduce heat conduction and gas–solid coupling effect simultaneously, thus the thermal conductivity is significantly reduced. Moreover, the porous films exhibited remarkable flexibility and hydrophobicity. Based on these properties, the porous films are highly promising in the field of thermal insulation protection and infrared stealth. [ABSTRACT FROM AUTHOR]

Electromagnetic (EM) contamination has now become a non‐negligible problem. To solve the EM contamination problem, it is imperative to develop high‐efficiency absorption materials with thin thickness, light weight, strong absorption properties, and broad absorption bands. Carbon nanotubes (CNTs) have a special helical structure and chirality, which will lead to special EM effects and therefore can absorb EM microwaves through magnetic polarization attenuation such as hysteresis loss, domain wall resonance, and aftereffect loss. Moreover, they have the characteristics of light weight, good compatibility, wide absorption frequency band, and high electrical loss angle tangent. In this paper, the different structures of CNT microwave‐absorbing composites are reviewed and the effects of the composite structures on the microwave‐absorbing properties are systematically discussed. The methods and mechanisms of surface modification of CNT absorber composites and the effects of modification on the absorber properties are summarized in detail. The progress of two specific CNT microwave‐absorbing composites, namely flexible and high‐temperature microwave‐absorbing composites, is briefly described. The shortcomings and challenges in the application of CNT microwave‐absorbing composites are described and future research directions for CNT microwave‐absorbing composites are explored. [ABSTRACT FROM AUTHOR]