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Stochastic chemical processes are described by the chemical master equation satisfying the law of mass-action. We first ask whether the dual master equation, which has the same steady state as the chemical master equation, but with inverted reaction currents, satisfies the law of mass-action and, hence, still describes a chemical process. We prove that the answer depends on the topological property of the underlying chemical reaction network known as deficiency. The answer is yes only for deficiency-zero networks. It is no for all other networks, implying that their steady-state currents cannot be inverted by controlling the kinetic constants of the reactions. Hence, the network deficiency imposes a form of non-invertibility to the chemical dynamics. We then ask whether catalytic chemical networks are deficiency-zero. We prove that the answer is no when they are driven out of equilibrium due to the exchange of some species with the environment. [ABSTRACT FROM AUTHOR]

[Display omitted] The lignin nanoparticles (LNPs) synthesis relies on lignin polymers with heterogeneous molecules and properties, which impose significant limitations on the preparation and property regulation. The multiscale structure of lignin from monomers to oligomers, provides a potential pathway for precise regulation of its physical and chemical properties. The study addresses this challenge by employing coniferyl alcohol and sinapyl alcohol as monomers and separately utilizing the Zulaufverfaren (ZL) and Zutropfverfaren (ZT) methods to synthesize different types of lignin dehydrogenation polymers (DHPs) including guaiacyl (G)-ZL-DHP, G-ZT-DHP, syringyl (S)-ZL-DHP, and S-ZT-DHP. The investigation highlights the chemical bonds as essential components of lignin primary structure. Additionally, the secondary structure is influenced by branched and linear molecular structures. G unit provides some branching points, which are utilized and amplified in the ZL process of DHPs synthesis. The branched DHPs aggregate at the edge and form rod-like LNPs. While linear DHPs aggregate around the center, presenting polygonal LNPs. The study identifies that the branched LNPs, characterized by more surface charges and lower steric hindrance, can form a stable complex with chitin nanofibers. Emulsions with varying oil-to-water ratios were subsequently prepared, opening a new window for the application of LNPs in fields such as food and cosmetics. [ABSTRACT FROM AUTHOR]

Porphyrazine is a macrocyclic molecule that has potential uses in biology and materials research. In this work, we investigate the topological characteristics of porphyrazine via topological indices. These indices are important in QSPR and QSAR modeling because they aid in the analysis and prediction of physical, biological, and chemical properties associated with a specific chemical structure. In this paper, we investigate neighborhood M-polynomial and graph index-entropy of porphyrazine graph, deriving several topological indices based on neighborhood degree sum from it, and numerical computation and graphical interpretation are used to explain the results further. This research advances our understanding of the basic principles of physics and chemistry by shedding light on the intricate connections between biological processes, chemical reactivity, and molecular structure. [ABSTRACT FROM AUTHOR]

Owing to its higher earth element reserve and similar chemical properties to lithium, potassium ion batteries (PIBs) have been regarded as a potential alternative to lithium-ion batteries. And considering the relatively larger ionic radius of potassium, available electrode materials need to be equipped with enough space for volume expansion during charge–discharge cycles, thus graphitic carbon nanomaterials with adjustable layer spacing gradually come into researcher's version. Here with copper nanowires serving as growth template and organic polyvinyl pyrrolidone (PVP) providing carbon source, freestanding and ultra-light graphitic carbon nanotube (GCNT) aerogels were simply assembled and annealed, which were directly used as anodes of PIBs. Annealing parameters (temperature and atmosphere) were adapted to regulate the lattice order and interlayer spacing of GCNTs, and N, O heteroatoms derived from PVP were directly doped into the carbon lattice during thermal annealing, to optimize and enhance the cycle capacity and rate performance of GCNT anodes. The electrochemical potassium storage mechanism of GCNTs was also quantitatively analyzed. Most of the potassium ions are reversibly stored by squeezing into and escaping from the carbon lattice, and simultaneously oxygen-containing functional groups with different chemical states also offer active redox sites and dedicate partial capacity. Therefore, our assembled GCNTs with large lumen are expected to sandwich-like load with active substances efficiently, further constructing next-generation PIBs with excellent performance. [ABSTRACT FROM AUTHOR]

Use of pozzolanic materials in concrete has become increasingly popular due to their ability to improve long-term strength and durability. To better understand their reactivity and reaction mechanism, proper characterization of their chemical properties is required. X-ray diffraction (XRD) is a widely used nondestructive testing method that can identify the different constituent phases of pozzolanic materials. However, the conventional qualitative approach for XRD analysis can be challenging due to the significant peak overlap and an amorphous hump in the baseline of XRD patterns. To address this issue, this study proposes a deep learning–based automated method for accurately identifying the minerals in pozzolanic materials using XRD patterns. The proposed method involves the deep learning–based peak picking algorithm, establishment of mineral candidates, and automated mineral identification using an optimization process. The performance of the model was validated using eight pozzolanic materials belonging to four classes (slag, fly ash, ground bottom ash, and silica fume). [ABSTRACT FROM AUTHOR]

Fullerene molecules have been intensively studied over the past few decades due to their unique chemical and physical properties, which have great potential in a wide range of applications. In this article, the formation and aging of C60 colloids in the xylene/ethanol system is considered. The peculiarities of these processes are studied by the methods of refractometry, optical absorption, Raman spectroscopy and dynamic light scattering (DLS). It has been experimentally established that the formation of colloidal particles in a C60/xylene/ethanol mixture depends on the volume content of the components and the storage time of the solution. The time required to achieve stability of self-organization of solute molecules in a C60/xylene/ethanol mixture is discussed. [ABSTRACT FROM AUTHOR]

Borosilicate glasses possess excellent melting properties and high stability against chemical attack by aqueous solutions, enabling this glass family to be used in various fields. In this article, we design a novel glass network in order to achieve a chemically robust glass with a low melting temperature. Therefore, the substitution effect of Na2O by MgO, Al2O3, Li2O, and K2O on the chemical durability and melting properties of sodium aluminosilicate glass (i.e., 80SiO2‒5Al2O3‒15Na2O [mol%]) was examined using a standard hydrolytic resistance test and viscosity measurement. Interestingly, we found that the partial replacement of Na2O by Al2O3, Li2O, and K2O (i.e., 80SiO2‒5Al2O3‒15Na2O → 80SiO2‒6.5Al2O3‒9Li2O‒2.25Na2O‒2.25K2O) makes the glass network with chemical durability and melting properties comparable to those of the commercial borosilicate network, resulting in a low HCl consumption of 0.04 mL/g and working temperature of 1238°C (i.e., temperature at viscosity 104 dPa s). The structural characterizations indicate that the high chemical stability of this glass composition originates from the abundance of SiO4 tetrahedrons with three and four bridging oxygen in the glass network as well as the increase in cationic field strength of mixed alkali ions. These excellent melting properties and superior chemical durability of glass imply the possibility of using the mixed alkali metal oxides aluminosilicate glass together with the commercial borosilicate glass in the markets for numerous practical applications. [ABSTRACT FROM AUTHOR]

Bone tissue engineering (BTE) applications and regenerative strategies have been used to improve the clinical practice of repairing large bone defects associated with surgical resections, congenital malformations, and trauma. The scaffolds are designed to stimulate a biological response, including cell interactions, and guide tissue regeneration by functioning as artificial biomimetic extracellular matrixes. Polymeric biomaterials are suitable for bone tissue engineering since they possess both chemical and physical properties, enabling the control of shape, morphology, and biodegradability, which makes them suitable for bone regeneration and tissue engineering applications. In vivo animal models were studied for collagen, chitosan, poly (lactic acid) (PLA) and high density polyethylene (HDPE), the four most common polymers employed in bone tissue engineering. Through analysis of the results of this review, the in vivo studies can provide a large-scale evaluation of the possibility of achieving optimal bone-forming capabilities and regenerative capabilities. Furthermore, the review will serve as an essential reference for bone tissue engineering applications as well as contribute to the development of novel in vivo investigations [ABSTRACT FROM AUTHOR]

[Display omitted] Heterojunctions and controllable anionic vacancies are perceived to be powerful means of ameliorating the performance of sodium-ion batteries assignable to their unique physical and chemical properties. However, the mechanism by which heterojunction and vacancy structures affect sodium-ion battery storage remains to be systemically explored. In this study, the Se doped CoS 2 @CoS 1.035 @Carbon (Se-CoS 2 @CoS 1.035 @C) heterostructure with anion vacancy was synthesized by a one-step calcination. These heterostructures with lower metal oxidation states and anionic vacancies exhibit exceptional Na+ storage performance (554.3 mA h g−1 after 1500 cycles at 5.0 A g−1). Both electrochemical tests and theoretical calculations demonstrate excellent pseudocapacitive behavior and enhanced Na+ adsorption during discharge because of anionic vacancies and Se doping. Additionally, introducing weaker Co-Se bonds and extending Co-S and Co-Se bonds reduce binding energies, which effectively accelerates the conversion reaction. Our findings provide a feasible way to rationally design and facilely prepare heterostructured anode materials with rich anionic vacancies for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • An innovative demineralization activating strategy is established to simultaneously regulating the interfacial properties and microstructure of lignite-derived carbon. • Demineralization process exposes more interfacial oxygen-containing functional groups in lignite. • Demineralization process introduces numerous voids and defects, resulting in the formation of highly-disordered microstructure. • The electrode shows a high reversible capacity, superb rate performance and excellent cycling stability in SIBs Lignite, as one of the coal materials, has been considered a promising precursor for hard carbon anodes in sodium-ion batteries (SIBs) owing to its low cost and high carbon yield. Nevertheless, hard carbon directly derived from lignite pyrolysis typically exhibits highly ordered microstructure with narrow interlayer spacing and relatively unreactive interfacial properties, owing to the abundance of polycyclic aromatic hydrocarbons and inert aromatic rings within its molecular composition. Herein, an innovative demineralization activating strategy is established to simultaneously modulate the interfacial properties and the microstructure of lignite-derived carbon for the development of high-performance SIBs. Demineralization process not only creates numerous void spaces in the matrix of lignite precursor to assist aromatic hydrocarbon rearrangement, thereby reducing the ordering and expanding interlayer spacing, but also exposes more interfacial oxygen-containing functional groups to effectively increasing the sodium storage active sites. As a result, the optimal demineralized lignite-derived hard carbon (DLHC 1300) delivers a high reversible capacity of 335.6 mAh g−1 at 30 mA g−1, superior rate performance of 246.3 mAh g−1 at 6 A g−1 and nearly 100 % capacity retention after 1100 cycles at 1A g−1. Furthermore, the optimized DLHC 1300 material functions as an outstanding anode in sodium ion full cells. This work significantly advances the development of low-cost, high-performance commercial hard carbon anodes for SIBs. [ABSTRACT FROM AUTHOR]

Peat is an unrenewable resource. Compost can partially replace peat in the growing seedling substrates due to its high electrical conductivity (EC), bulk density (BD), and pH. This study aimed to assess the potential of substituting peat for seedling substrate with compost made from a mixture of agricultural and agro-industrial wastes. Four compost piles (C1–C4) were constructed as follows: C1: a 1:1:1.5 weight ratio mixture of filter mud, mushroom waste, and date-palm fronds, while C2–C4: a 0.5:1 weight ratio mixture of either bagasse, cutting grassland, or date-palm fronds and cattle dung. After four months of decomposition, the compost's physical, chemical, and biological properties were estimated in comparison to commercial compost (CC), peatmoss (PM), and their ideal ranges (IR) for seed germination and seedling growth. Composts differed significantly in their physical and chemical properties. Some composts revealed property values within the IR. In comparison to PM, Composts have a lower C/N ratio and organic matter, along with higher BD, EC, and pH. Cattle manure enhanced organic matter and carbon, total nitrogen and potassium, and ammonium levels, and reduced ash levels in C2–C4 compared to filter mud in C1. In winter 2018 and 2019, C1–C4 substrates were compared with CC and PM substrates to determine their suitability for producing crisp lettuce 'Big Bell' seedlings under plastic-house conditions. Substrates had significant effects on lettuce seedling traits. Shoots of C2–C4 substrate seedlings grew more rapidly than those of other substrate seedlings due to the increased length and diameter of their stem and leaf area. [ABSTRACT FROM AUTHOR]

Schematic illustration of the fabrication processes of NYCs samples under different pyrolysis temperature. [Display omitted] The energy storage capacity of porous carbon materials is closely tied to their surface structure and chemical properties. However, developing an innovative and straightforward approach to synthesize yolk-shell carbon spheres (YCs) remains a great challenge till date. Herein, we prepared a series of porous nitrogen-doped yolk-shell carbon spheres (NYCs) via a "pyrolysis-capture" method. This method involves coating the resorcinol–formaldehyde (RF) resin sphere with a layer of compact silica shell induced by 2-methylimidazole (ME) catalysis to produce a confined nano-space. Based on the confined effect of compact silica shell, volatile gases emitted from the RF resin and ME during pyrolysis can not only diffuse into the pores of the RF resin but can also be captured to form an outer carbon shell. This results in the tunable structures of NYCs materials. As the pyrolysis temperature rises, the shell thickness of NYCs reduces, the pore size expands, the roughness increases, and the N/O content of surface elements is enhanced. Notably, as an electrode material used for supercapacitors, the optimized NYCs-800 exhibits excellent performance with a capacitance of 301.2F g−1 at the current density of 1 A/g and outstanding cycling life stability of 96.1% after 10,000 cycles. These results signify that controlling the surface structure and chemical properties of NYCs materials is an effective approach for constructing advanced energy storage materials. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of sustainable urethane coatings derived from alkyds of Camelina oil (CO) monoglycerides, offering a sustainable alternative to petrochemical resources. Utilizing immobilized lipase for a low‐temperature glycerolysis reaction, high‐yield monoglycerides were obtained from CO. These were then reacted with dibasic acids (phthalic, succinic, and maleic anhydride) to produce alkyd diols, confirmed by both nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy. The hydroxyl functionality of the alkyd diols showed a significant enhancement (up to 2200%) over crude CO produced Camelina‐based alkyd diols were incorporated into polyurethane formulations and applied to metal substrates. Comprehensive performance evaluations revealed their superior mechanical, thermal, and chemical properties in comparison with previously reported plant‐based alkyd‐urethane coatings, especially for the phthalic anhydride‐derived alkyd diol. The present research underscores the potential of Camelina‐derived alkyds in creating high‐performance, plant‐based coatings, aligning with recent sustainability trends in material science. [ABSTRACT FROM AUTHOR]

This study investigated the prospective effect of ApnA enzyme under different concentrations (µL/100 mL soymilk) compared to chemical (pH, MgCl2, and K-carrageenan, respectively) as tofu coagulants. The resultant tofu samples were analyzed for compositional analysis, thermal properties, water distribution, and microstructure properties. The higher concentration of enzyme used, the higher resulted moisture content of tofu. ApnA enzyme increased the cross-linking through protein molecules and trapped more water within the gel network. Tofu samples prepared by different concentrations of ApnA enzyme displayed significantly less freezable water content (15.44, 12.84, and 19.46 g/100 g). In particular, 800 µL ApnA/100 mL soymilk formed an interconnected gel matrix with regular distribution with almost invisible cavities. The thermal pretreatment and the increased coagulation time might encourage this irregular structure. On the other hand, the gel network coagulated using the reduction of pH showed a weaker gel due to an accelerated acidification. [ABSTRACT FROM AUTHOR]

We report the comparison of multiple acetylene black (AB) rigid carbon composites for electrochemical purposes exploring several binders, including one (polyurethane) from a renewable source of castor oil. The acetylene black–based composites presented less roughness and increased surface homogeneity evinced by AFM and SEM images within the micrometer range. Contact angle analysis and Raman spectra confirmed a high degree of surface functionalization associated with structural defects on AB even when the base conductive material is associated with a non-conductive binder. The acetylene black-castor oil electrode presented superior performance (lower resistance to charge transfer and increased peak currents) when compared to its graphite counterparts regardless of the mechanical activation. The proposed electrode presented an excellent electrochemical performance in analyzing contaminants of emerging concern when compared to glassy carbon electrodes. The sustainable aspect of this work is evinced considering the room temperature synthesis, low cost of the AB, and renewable castor oil binder source. [ABSTRACT FROM AUTHOR]

We investigated the potential of earthworm casts to emit N2O, hypothesizing that emission levels are influenced by the species of earthworm and their ecological category. This study examined casts a broad taxonomic and ecological coverage of tropical earthworms, i.e., 16 different species across four ecological categories. We quantified the potential nitrification, N2O production and consumption as well as the abundance of N-related microbial functional groups, including ammonia-oxidizers, nitrite-reducers, and distinct clades of N2O-reducers, along with casts chemical properties to determine cast organic matter quality and substrate availability. Earthworm casts exhibited significantly higher concentrations of carbon, nitrogen, and nitrate compared to control soil, while humification index were lower. A negative correlation between humification index and potential N₂O production suggests that more labile substrates in the casts promote higher N₂O flux. Net potential N₂O emissions were higher in the casts of 7 out of 16 species compared to control soil, and all species' casts showed higher gross potential N₂O production, with substantial interspecific variability. The abundance of nitrite and N₂O reducers was significantly higher in the casts and positively correlated with potential N₂O emissions. Casts from epigeic and mixed categories displayed higher carbon and nitrogen content, abundance of nitrite and N₂O reducers, ammonia-oxidizing bacteria, and potential N₂O production compared to anecic and endogeic categories, which exhibited higher values of humification index. Structural equation modeling indicated that gross potential N₂O production was primarily explained by the abundance of nitrite reducers and substrate availability indicators such as humification index and nitrate concentration. Our study demonstrates significant interspecific variability in N₂O potential emissions from a broad range of tropical earthworm casts, influenced by species feeding behavior, microbial communities, and substrate availability. [ABSTRACT FROM AUTHOR]

Understanding of dicofol's behavior in soil is crucial for more precise pest control and minimal environmental effect. Therefore, the goal of this study was to assess how the physicochemical characteristics of 10 selected soils effects the sorption and degradation of dicofol behavior. The behavior of dicofol, including its adsorption and desorption properties as well as its rates of hydrolysis and photolysis degradation, was thoroughly examined via definitive studies. Standard batch equilibration mode for sorption revealed that it was dependent on the physical and chemical properties of the soil. Exothermic and spontaneous adsorption processes, which were characterized by a negative Gibbs free energy value, were convincingly proven by thermodynamic study. The current investigation's ΔG estimations varied from −18.6 kjmol−1 for soil-6 to −24.25 kjmol−1 for soil-9. The soil-7 with a notable organic matter content (1.81%) showed the maximum adsorption, and subsequently producing a C-type isotherm that was analyzed using a linear and Freundlich model. An analytical process using UV-VIS spectrophotometry to determine the fate of dicofol in soil matrices. Hydrolysis and photolysis studies yielded minimum half-lives of 13.4 and 1.32 days, respectively. It has been demonstrated that dicofol molecules interact strongly with soils, principally via physio-sorption mechanisms. In contrast to its strong soil affinity and permanence, dicofol exhibits a counterintuitive behavior that makes it vulnerable to sunlight-induced deterioration. Future studies will concentrate on enhancing these pathways to assist sustainable pesticide management strategies and creative pollution mitigation techniques. [ABSTRACT FROM AUTHOR]

Ceramic materials with excellent radiation resistance stability play an indispensable role in the treatment of nuclear waste. This article uses spark plasma sintering (SPS) to synthesize high-entropy (HE) Y 0.6 Gd 0.6 Sm 0.6 Eu 0.6 Dy 0. 6 Fe 5 O 12 (HEG) and traditional garnet Y 1.2 Nd 1.8 Fe 5 O 12 (YIG). Studied the effects of 2 MeV He2+ irradiation (1 × 1014 ions/cm2 - 1 × 1017 ions/cm2) on the crystal structure, mechanical properties, and chemical stability of ceramics. Research shows that the surface of YIG becomes completely amorphous under ∼30dpa irradiation. Under irradiation at∼30dpa, HEG underwent a small amount of amorphization (with an amorphization rate of 38 %), maintaining the structure of garnet, and the lattice expansion rate of HEG caused by irradiation was lower than that of YIG. After irradiation, the mechanical properties of HEG were improved, while YIG's hardness decreased due to its amorphous state. Radiation has almost no effect on the chemical stability of HEG, and its long-term release mechanism is dominated by diffusion. This study identified HEG as an ideal candidate substrate for immobilizing high-radioactive waste (HLW) the perspective of radiation resistance. [ABSTRACT FROM AUTHOR]

This experimental work presents the effects of integrating nanocenospheres into asphalt binders. Nanocenospheres are hollow spherical nanoparticles sourced from thermal power plants. They are characterized by size, shape, and chemical composition, followed by the production of nanocenosphere-modified asphalt binders (NMB) with varying concentrations (0%, 0.5%, 1%, 2%, and 3%) of nanocenosphere particles. A series of experimental tests, including scanning electronic microscopy (SEM), Fourier infrared and transform spectroscopy, X-ray diffraction (XRD), penetration, softening point, ductility, performance grading, temperature sweep, multiple stress and creep recovery (MSCR), frequency sweep, linear amplitude sweep (LAS), and rutting aging index are conducted to evaluate changes in physical, morphological, rheological, and chemical properties. Incorporating nanocenospheres into the asphalt binder alters its characteristics, resulting in improved physical and rheological performance. Optimal results are observed with a 2% proportion of nanocenospheres relative to the weight of the control asphalt binder. [ABSTRACT FROM AUTHOR]

Spin-coated thin films of lactoperoxidase enzyme (LPO) were used on conjunction with the bio-composite (chitosan–gelatin), glutaraldehyde and cysteine as first-layers to characterize the interactions on the sensing characteristics. The prospect of tuning these three under-layers is to investigate the change of active vapor binding sites of LPO film after inter-layer interactions. Initially, spin-coated thin film properties of three under-layers and LPO are investigated by reporting deposited mass and layer thickness using the quartz crystal microbalance (QCM) frequency change. LPO spin-coated films with different under-layers are exposed to formic acid, acetic acid, chloroform, acetone and ethyl acetate vapors. The response characteristics of LPO films are investigated via QCM using time dependence frequency recording. LPO films are sensitive to those five vapors and the chemical and the physical properties of the analytes affect the sensitivity and the response rate. The results showed that the structural changes in the thin film affect the number of active binding sites of sensitive layer and thus the sensor response can be enhanced. [ABSTRACT FROM AUTHOR]

This study evaluated the antiseptic effect of 0.25% chlorhexidine nanoemulsion (NM-Cl) on cat skin and compare its effect with that of 2.0% chlorhexidine digluconate (CS-Cl). NM-Cl was synthesized using the spontaneous emulsification method, and physical and chemical properties were analyzed. The antiseptic effects of NM-Cl and CS-Cl were randomly tested on the thoracic limbs of 10 healthy male cats. After a wide trichotomy of the thoracic limbs, NM-Cl was randomly applied to the trichotomy area of the right (n = 5) or left (n = 5) thoracic limbs. Then, a catheter was inserted aseptically in the cephalic vein. Subsequently, the same procedure was performed using CS-Cl on the contralateral limb. Cutaneous microbiota swab samples were obtained before antisepsis (Tpre); immediately after antisepsis (Tpost); and 4, 8, and 24 h after antisepsis. The collected samples were immediately inoculated on blood agar plates and incubated at 35 ºC ± 2 ºC in aerobiosis. Colony-forming units (CFUs) were manually counted after 24 h of inoculation. The Kruskal–Wallis and Mann–Whitney U tests were performed between groups and within the same group at different sample times, respectively. The NM-Cl and CS-Cl groups showed a reduction in CFUs between Tpre and Tpost in all animals (P < 0.001). Both formulations presented an antiseptic effect 24 h of antisepsis (P < 0.05), and no difference was observed between formulations at different times (P < 0.05). With a lower concentration of chlorhexidine than CS-Cl, NM-Cl presents effective antiseptic action and prolonged residual effect in antisepsis for cat venipuncture. [ABSTRACT FROM AUTHOR]

Precise control over sequence structure in copolymers is essential for chemical product engineering. The complexity of sequence structures results in the challenging characterization of monomer sequences. Herein, a chemical composition model (CD model) is developed to record the distribution density of monomers in the chain segment, where the deviation of the chemical composition function between a copolymer and its ideal sequence structure can directly map the sequence structure quality. The application of the CD model in randomly generated virtual copolymers demonstrates that the model has great sensitivity and discrimination to evaluate sequence structures accurately. Furthermore, the CD model is combined with the kinetic Monte Carlo algorithm to explicitly track the evolution of sequence structure quality in the copolymerization process. The CD model provides an insight into the evolution of sequence structure, which is conducive to building the bridge between molecular structure and properties for the development of chemical product engineering. [ABSTRACT FROM AUTHOR]

Melanins are macromolecular pigments widely spread in many living organisms, with unique physical and chemical properties. Specifically, their conductive properties have drawn attention for applications in different devices; however, the electrochemical response is equally necessary for designing technologies in sustainable bioelectronics. In this sense, we report a comparative study of the redox electrochemical properties of non‐functionalized and sulfonated melanins in different pH environments. The electrochemical response was investigated using cyclic voltammetry, electrochemical impedance spectroscopy, dielectric permittivity and AC/DC conductivity at pH 3, 5 and 7. The voltammetric currents were higher at low pH, in agreement with the known proton transport properties of melanins. The effect of pH on electrochemical properties was slightly more significant in non‐functionalized pigments. Melanins with a higher 5,6‐dihydroxyindole carboxylic acid/5,6‐dihydroxyindole ratio showed high DC current and low impedance. No significant difference was observed in the dielectric relaxation process between the different samples. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A linear model for predicting the ignition delay time of hypergolic ignition is presented based on thermal diffusion theory. The heat released by the hypergolic reaction is assumed to diffuse through a given length scale while being governed by a heat source in the form of an Arrhenius equation. A linearized approach is used to reach analytical expressions for the ignition delay times, defined when the temperature change at the reactants interface drastically increases, diverges, or tends toward infinity. Ignition delay times for three different geometries, cartesian, cylindrical, and spherical, are derived and compared. The results show that, for spherical coordinates, the ignition depends on a critical condition, which is based on material and chemical properties and geometry. A prediction of the ignition condition for all cases where one of the reactants is a droplet/particle is given. The ignition process is analyzed based on non-dimensional parameters in order to understand the behavior of the temperature change during ignition. The results obtained are consistent with results presented in the literature. In addition, a prediction for ignition delay times is provided. [ABSTRACT FROM AUTHOR]

The spontaneous combustion and gas explosion induced by crushed small coal pillars and the residual coal of adjacent goaf will cause a large amount of coal loss and casualties of workers. Moreover, it also seriously pollutes the environment and aggravates the greenhouse effect. To effectively block small coal pillars and fracture zones of adjacent old workings is the key to prevent gas and coal spontaneous combustion in small coal pillars. However, the commonly used blocking materials at present are easy to shrink and chap after air drying, and they have no chemical inhibitory property. Thus, these materials cannot realize the coordinated prevention of gas and coal spontaneous combustion. In this paper, a low-cost and eco-friendly Synergistic Inhibiting and Sealing Material (SISM)with strong inhibitory properties is proposed. The optimal ratio of the material was determined by experiments. The inhibitory properties of the material are analyzed by testing and comparing the generation rate of free radical and CO generation rate. The experimental results showed that the optimal molar ratio of main antioxidant and auxiliary antioxidant was 5:2, and the optimal mass ratio of synergistic antioxidant and high water material was 1:8. Secondly, SISM can prevent or delay the production of new free radicals during coal spontaneous combustion, significantly reduce the concentration of free radicals in coal and finally delay the process of coal spontaneous combustion. Thirdly, both physical and chemical inhibitory properties are taken into account when preparing SISM. Hence, it can maintain both high inhibitory properties in the whole temperature range and the inhibition effect on coal-oxygen compound reaction, which is significantly better than MgCl2 and yellow mud (YM) with only physical inhibition. [ABSTRACT FROM AUTHOR]

Semi-empirical quantum models such as Density Functional Tight Binding (DFTB) are attractive methods for obtaining quantum simulation data at longer time and length scales than possible with standard approaches. However, application of these models can require lengthy effort due to the lack of a systematic approach for their development. In this work, we discuss the use of the Chebyshev Interaction Model for Efficient Simulation (ChIMES) to create rapidly parameterized DFTB models, which exhibit strong transferability due to the inclusion of many-body interactions that might otherwise be inaccurate. We apply our modeling approach to silicon polymorphs and review previous work on titanium hydride. We also review the creation of a general purpose DFTB/ChIMES model for organic molecules and compounds that approaches hybrid functional and coupled cluster accuracy with two orders of magnitude fewer parameters than similar neural network approaches. In all cases, DFTB/ChIMES yields similar accuracy to the underlying quantum method with orders of magnitude improvement in computational cost. Our developments provide a way to create computationally efficient and highly accurate simulations over varying extreme thermodynamic conditions, where physical and chemical properties can be difficult to interrogate directly, and there is historically a significant reliance on theoretical approaches for interpretation and validation of experimental results. [ABSTRACT FROM AUTHOR]

While ice has very low solubility for salts compared to water, small amounts of ions are doped into ice crystals. These small ion dopants can alter the fundamental physical and chemical properties of ice, such as its structure and electrical conductivity. Therefore, these results could have a direct impact on the chemical reactivity of ice and ice surfaces. Here, we examine the influence of the uptake of three salts—ammonium chloride (NH4Cl), sodium chloride (NaCl), and ammonium sulfate [(NH4)2SO4]—on ice Ih formation using capillary electrophoresis. Using both cation and anion modes, we observed and quantified the uptake of individual ions into the ice. Our results indicate that anions have a higher propensity for uptake into ice Ih crystals. [ABSTRACT FROM AUTHOR]

The “Felina 32” variety of industrial hemp (Cannabis sativa L.) is among the most popular cultivated varieties in Lithuania. In 2020 to 2021, the height of the above-ground portion of “Felina 32” ranged from about 1.37 to 2.52 m. In the less favorable year of 2021, 9.8% lower height and 28.5% lower mass plants grew. However, the impact of meteorological conditions on their comparative indicators was not confirmed. Two critical intervals were distinguished, which essentially influence the dynamics of plant growth: crop density of 90 to 150 plants∙m2 and plant height of 1.9 m to 1.99 m. Lower crop density results in larger plants, and plants taller than 1.9 m gain mass 2.58 times faster than shorter plants. In addition, industrial hemp of different heights is characterized by differences in the development of morphological parts. This directly affects the physical and chemical properties of biomass. It was determined that when the height of “Felina 32” variety changes, the heat value of biomass increases 0.342 MJ/kg, carbon concentration increases 0.70%, and ash content, sulfur, nitrogen, and chlorine concentrations decreased.

AbstractThis study aims to evaluate the effectiveness of the composite films of chitosan (Ch) and silver nanoparticles (AgNPs) biosynthesized by the Aspergillus niger on the chemical qualities and microbial content of chicken breasts meat during storage at 4°C for 28 days. Over storage time pH, moisture content, and peroxide number of chicken breast meat were analyzed. The results indicated that the films of Ch alone or Ch-AgNPs had increased the values of all parameters the preservation periods. Regarding the microbial content, total bacterial count was decreased in both Ch and Ag-NPs over time cpared to the control. While lowest level was found in Ch-AgNPs samples These findings demonstrated that the meat samples coated with either Ch or Ch-AgNPs performed better than those without coating the during storage time. The Ch-AgNPs film became thicker after AgNPs were added. The chicken breast sample coated with Ch-AgNPs preserved the moisture content, pH values, peroxide number, percentage of F.F.A and bacterial counts better compared to the Ch sample and compared after 28 days of preservation, the values were %75.91, 6.9, 0.42 (mgO2/100g), %0.95, 5.08 (log10 cfu/g) respectively, which caused prolongation of the shelf life of the Ch-AgNPs sample.

Three-dimensional (3D) tissue-engineered scaffolds mimic the physiological environment of cells by providing essential structural support, biochemical cues, and the mechanical strength needed for cell adhesion, proliferation, migration, and differentiation. Hydrogels like polyethylene glycol diacrylate (PEGDA) are commonly used biomaterials for cell culture due to their affordability, tunable stiffness, and ability to efficiently transport nutrients and gases. However, PEGDA lacks cell adhesion sites essential for cell proliferation and migration and has limited degradability. Methacrylated gelatin (GelMA) produced from denatured bovine collagen, crosslinks under ultraviolet light (UV) resulting in a degradable hydrogel with cell adhesion sites. Here, we synthesized GelMA with variable degree of methacrylation and crosslinked it with PEGDA to produce cell scaffolds with independently tunable mechanical and biochemical properties by varying the ratios of the two polymers. We determined polymer ratios that resulted in scaffolds with different mechanical properties but the same gelatin concentrations (providing cell adhesion and degradation sites) as well as different gelatin concentrations but the same mechanical properties. With the developed scaffold library, we further used a design of experiments approach to probe the parameter space and perform detailed analysis on chemical compositionscaffold properties as well as scaffold properties-cell behavior correlations. Our findings showed that hydrogel properties such as modulus, swelling, pore size, and permeability, strongly depended on total polymer concentration and not on theGelMA fraction. GelMA significantly influenced cell spreading, while addition of any amount of PEGDA delayed cell spreading significantly. We suggest that such analysis will broaden the utility of the GelMA/PEGDA hydrogels, presenting a versatile platform for mechanosensing research in 3D environments. [ABSTRACT FROM AUTHOR]

This work focuses on utilizing the X‐ray diffraction technique as an alternative method to specialized and high‐cost techniques such as X‐ray photoelectron spectroscopy to obtain the cation distribution in magnetic nanoparticles as MFe2O4 with spinel structure synthesized by thermal decomposition. X‐ray diffraction measurements for MFe2O4 with M = Co2+ as transition cation (inverse spinel CoFe2O4) showed sensitivity to the cation distribution for octahedral and tetrahedral sites in this material with this kind of crystalline structure, being a good option for its determination. The cation distribution was obtained from the X‐ray diffraction intensity ratios for the most sensitive crystalline planes to the cations in octahedral and tetrahedral sites. Besides, the Debye–Scherrer equation and line profile analysis method from the diffraction pattern were used to determine the size distribution and the crystallite size. The size distribution obtained by X‐ray diffraction was from 15 to 18 nm, while transmission electron microscopy was found to be from 10 to 25 nm. The inversion degree x derived from X‐ray diffraction exhibits variability within the interval 0.6 < x < 0.8, not very far from that obtained by X‐ray photoelectron spectroscopy (x = 0.67). This material exhibits a saturation magnetization of 124.88 emu g−1. Consequently, the X‐ray diffraction technique opens the possibility of obtaining reliable information related to nanoparticles' morphological and chemical properties with spinel structure. [ABSTRACT FROM AUTHOR]

The pigeon pea has high nutritional value and for diversifying utilization of sustainable legume crop i.e pigeon pea, for making alternative products with high nutritional value is an utmost to provide nutrient-rich food to the proving population. The present work focused on a comparative assessment of three pigeon pea varieties namely PAU 881, AL 882, and AL 201. The whole pigeon pea was assessed for test weight, coefficient of internal/external friction, angle of repose, and the pigeon pea flour was assessed for moisture, crude fat, crude protein, ash, crude fiber, carbohydrates, mineral content, fatty acid profile, foaming capacity, emulsification activity, pasting properties, and thermal properties. Further, batter was prepared using pigeon pea flour and water in the ratio of 1:1.6 (w/v) and analyzed rheological behavior of standard frying coating batter. The results revealed that the pigeon pea varieties had significant differences in proximate composition and functional properties. The pasting properties of AL 201 pigeon pea variety were significantly lower than the other pigeon pea varieties. In particular, the PAU 881 pigeon pea variety exhibited a better nutritional quality including macro and micro minerals. Moreover, the rheological parameters of PAU 881 were found better than the other two, indicating its potential for the preparation of frying coating batter like chickpea flour. Since chickpeas are widely used as a coating batter in a variety of products, underutilized pulses like pigeon pea are being investigated to see what potential they may have. This study will pave the future way of research and provide holistic view of approach to develop technology and engineering mechanization for various food products development. [ABSTRACT FROM AUTHOR]

Soil degradation, marked by declining organic matter, threatens global food security. The impact of brewer's spent yeast (BSY) on clay and sand was analysed at varying application rates to assess its effectiveness in improving soil quality. A randomized complete block design with three replicates was employed. One kilogram of soil were mixed with BSY at application rates of 2 t/ha and 5 t/ha. The samples were incubated at 26 °C for 5 months with daily watering. We analysed pH, total nitrogen, organic carbon, total phosphorus, and electrical conductivity (EC); microbial activity (total heterotrophic bacteria, actinobacteria, and fungi) and soil enzyme activity (dehydrogenase, catalase, protease). BSY application improved soil quality, particularly in clay. Clay showed increased in pH, EC, N and C. BSY significantly boosted microbial populations (bacteria, fungi) in clay with a lesser effect in sand. Enzyme activity and a fertility index also improved in BSY-treated clay, while sand displayed increased activity of a different enzyme. Results suggest BSY holds promise as an organic fertilizer, especially for clay soils. Further research is needed to optimize application, understand long-term effects, and evaluate economic feasibility and social acceptance. This study contributes to the search for sustainable, local solutions to improve soil health and agricultural practices. [ABSTRACT FROM AUTHOR]

Monoanionic gold bis(dithiolene) complexes were recently shown to display activity against ovarian cancer cells, Gram-positive bacteria, Candida strains and the rodent malaria parasite, P. berghei. To date, only monoanionic gold(III) bis(dithiolene) complexes with a thiazoline backbone substituted with small alkyl chains have been evaluated for biomedical applications. We now analyzed the influence of the length and the hydrophobicity vs. hydrophilicity of these complexes' alkyl chain on their anticancer and antiplasmodial properties. Isomer analogues of these monoanionic gold(III) bis(dithiolene) complexes, this time with a thiazole backbone, were also investigated in order to assess the influence of the nature of the heterocyclic ligand on their overall chemical and biological properties. In this report we present the total synthesis of four novel monoanionic gold(III) bis(dithiolene) complexes with a long alkyl chain and a polyoxygenated (PEG) chain aiming to improve their solubility and biological properties. Our results showed that the complexes with a PEG chain showed promising anticancer and antiplasmodial activities beside improved solubility, a key parameter in drug discovery and development. [ABSTRACT FROM AUTHOR]

The newly updated GIZMO and Simba based simulation, Simba-C , with its new stellar feedback, chemical enrichment, and recalibrated AGN feedback, allows for a detailed study of the intragroup medium X-ray properties. We discuss the impact of various physical mechanisms, e.g. stellar and AGN feedback, and chemical enrichment, on the composition and the global scaling relations of nearby galaxy groups. We also study the evolution (z = 2 to 0) of the global properties for the |$1\, \mathrm{keV}$| temperature groups. Simba-C shows improved consistent matching with the observations of all X-ray scaling relations compared to Simba. It is well known that AGN feedback has a significant influence on L X, 0.5–2.0– T spec, corr, S 500/2500– T spec, corr, and gas mass fractions, with our Simba-C results consistent with it. Our recalibrated AGN feedback strength also showed an additional improvement in gas entropy, which now aligns with CLoGS observations. The updated stellar feedback and chemical enrichment model is shown to play an important role in our understanding of the chemical abundance ratios and their evolution within galaxy groups. In particular, we find that Simba-C produces an increase in the amount of heavier elements (specifically Si and Fe) relative to O, compared to Simba. [ABSTRACT FROM AUTHOR]

Phase transitions in molecular solids involve synergistic changes in chemical and electronic structures, leading to diversification in physical and chemical properties. Despite the pivotal role of hydrogen bonds (H‐bonds) in many phase‐transition materials, it is rare and challenging to chemically regulate the dynamics and to elucidate the structure‐property relationship. Here, four high‐spin CoII compounds were isolated and systematically investigated by modifying the ligand terminal groups (X=S, Se) and substituents (Y=Cl, Br). S−Cl and Se−Br undergo a reversible structural phase transition near room temperature, triggering the rotation of 15‐crown‐5 guests and the swing between syn‐ and anti‐conformation of NCX− ligands, accompanied by switchable magnetism. Conversely, S−Br and Se−Cl retain stability in ordered and disordered phases, respectively. H‐bonds geometric analysis and ab initio calculations reveal that the electronegativity of X and Y affects the strength of NY‐ap−H⋅⋅⋅X interactions. Entropy‐driven structural phase transitions occur when the H‐bond strength is appropriate; otherwise, the phase stays unchanged if it is too strong or weak. This work highlights a phase transition driven by H‐bond strength complementarity – pairing strong acceptor with weak donor and vice versa, which offers a straightforward and effective approach for designing phase‐transition molecular solids from a chemical perspective. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) lamellar membranes, featuring organized nanochannels, tunable interlayer spacing, and modifiable chemical properties, are emerging as promising candidates for both theoretical research and practical applications. Rational design and regulation of the physical/chemical properties of the nanofluidic channels as well as manipulation of external factors are crucial to achieve desirable performance for the applications related to mass transport. Focusing on the recent advances in ion and water transport within 2D nanofluidic channels, this work gives a brief overview of the fabrication of 2D lamellar membranes based on the strategy of exfoliation and reconstruction. Then the transport phenomena within 2D nanofluidic channels along with the mechanisms and influential factors are highlighted. The representative applications of 2D lamellar membranes are also covered, especially in the areas of osmotic energy conversion, water purification and desalination, as well as single‐ion separation and extraction. It is concluded with a discussion of the current challenges and future perspectives in this potential field. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) layered materials have been studied in depth during the past two decades due to their unique structure and properties. Transition metal (TM) intercalation of layered materials have been proven as an effective way to introduce new physical properties, such as tunable 2D magnetism, but the direct growth of atomically thin heteroatoms-intercalated layered materials remains untapped. Herein, we directly synthesize various ultrathin heteroatoms-intercalated 2D layered materials (UHI-2DMs) through flux-assisted growth (FAG) approach. Eight UHI-2DMs (V1/3NbS2, Cr1/3NbS2, Mn1/3NbS2, Fe1/3NbS2, Co1/3NbS2, Co1/3NbSe2, Fe1/3TaS2, Fe1/4TaS2) were successfully synthesized. Their thickness can be reduced to the thinnest limit (bilayer 2D material with monolayer intercalated TM), and magnetic ordering can be induced in the synthesized structures. Interestingly, due to the possible anisotropy-stabilized long-range ferromagnetism in Fe1/3TaS2 with weak interlayer coupling, the layer-independent magnetic ordering temperature of Fe1/3TaS2 was revealed by magneto-transport properties. This work establishes a general method for direct synthesis of heteroatom-intercalated ultrathin 2D materials with tunable chemical and physical properties. The intercalation of heteroatoms has been demonstrated to be an effective approach to introduce new physical properties in 2D layered materials (2DMs). Here, the authors report a flux-assisted growth method to synthesize various ultrathin heteroatoms-intercalated 2DMs, showing evidence of anisotropy-stabilized long-range ferromagnetism in Fe1/3TaS2. [ABSTRACT FROM AUTHOR]

Iminosydnones (ImSyds) have renowned biological activities and attractive chemical properties for chemical biology. However, access to N6‐functionalized iminosydnones involves tricky and hazardous procedures. Thanks to an innovative mechanochemical strategy using 1,1'‐carbonyldiimidazole (CDI) as an activating agent, a straightforward synthesis of molsidomine and of a mesocarb analog, two bioactive iminosydnones, was achieved. The whole process, involving 4 linear steps, was carried out in the solid state by ball‐milling and with safe reagents, offering efficient and sustainable access to N‐carbonylated iminosydnones, in agreement with the principles of green chemistry. [ABSTRACT FROM AUTHOR]

The chemical and biological conversion of biomass-derived lignin is a promising pathway for producing valuable low molecular weight aromatic chemicals, such as vanillin or guaiacol, known as lignin monomers (LMs). Various methods employing chromatography and electrospray ionization-mass spectrometry (ESI–MS) have been developed for LM analysis, but the impact of LM chemical properties on analytical performance remains unclear. This study systematically optimized ESI efficiency for 24 selected LMs, categorized by functionality. Fractional factorial designs were employed for each LM to assess ESI parameter effects on ionization efficiency using ultra-high-performance supercritical fluid chromatography/ESI–MS (UHPSFC/ESI–MS). Molecular descriptors were also investigated to explain variations in ESI parameter responses and chromatographic retention among the LMs. Structural differences among LMs led to complex optimal ESI settings. Notably, LMs with two methoxy groups benefited from higher gas and sheath gas temperatures, likely due to their lower log P and higher desolvation energy requirements. Similarly, vinyl acids and ketones showed advantages at elevated gas temperatures. The retention in UHPSFC using a diol stationary phase was correlated with the number of hydrogen bond donors. In summary, this study elucidates structural features influencing chromatographic retention and ESI efficiency in LMs. The findings can aid in developing analytical methods for specific technical lignins. However, the absence of an adequate number of LM standards limits the prediction of LM structures solely based on ESI performance data. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases (NDDs) have received considerable interest from scientists for a long time due to their multifactorial nature. Alzheimer's disease (AD) is of particular importance among pathologies, and despite approved drugs for its treatment, there is no effective pharmacological therapy to stop, halt, or repair neurodegeneration. The U.S. Food and Drug Administration (FDA) has approved certain medications to treat AD, including galantamine, donepezil, rivastigmine, memantine, tacrine, suvorexant, brexpiprazole, butein, and Licochalcone A. Topological indices and quantitative structure‐property relationships (QSPRs) are indispensable in drug discovery. They allow researchers to analyze, compare, and predict the properties of chemical compounds, thereby expediting the identification of promising drug candidates while minimizing experimental costs and efforts. Regression models are vital in QSPR analysis, especially when dealing with topological indices. They facilitate quantifying the relationship between chemical structure and properties, thereby facilitating drug design, material discovery, and other chemistry‐related applications. The objective of this study is to examine the efficacy of descriptors in correlating the physicochemical features of molecules associated with Alzheimer's disease. We will use the computational method to calculate degree‐related, distance‐related, and eccentricity‐based topological indices for any chemical graph. QSPR models are developed utilizing degree‐based, distance‐based, and eccentricity‐based topological indices to estimate some physicochemical properties of AD drugs, including molecular weight (MW), boiling point (BP), topological polar surface area (TPSA), complexity (C), polarizability (P), and refractive index (R). The QSPRS studies are obtained using the linear regression technique. The present study found that the topological indices Randic index R, first Zagreb index M1, and atom‐bond connectivity index ABC provide valuable insights into the structure‐activity relationships of different drugs and help in designing more effective combinations for treating Alzheimer's disease. [ABSTRACT FROM AUTHOR]

A chemical bath deposition (CBD) is applied to deposit n‐type iron sulfide (FeSxOy) film on fluorine (F)‐doped tin oxide (SnO2)–FTO substrate. The duration, temperature, and magnetic stirrer's speed in CBD are 3 h, 75 °C, and 100 revolutions per minute. The influence of complexing agents’ concentration (≤200 mm)–acid (tartaric and lactic) on the physicochemical properties of film is studied. All films are n‐type semiconductors with large bandgap (2.95–3.58 eV) and contain high oxygen (≈56–83%). Scanning electron microscopy image shows the 50 mm tartaric acid film has a uniform and denser surface morphology. FeSxOy film with tartaric acid has lesser goethite and hematite peaks in X‐ray diffraction than lactic acid. The FeSxOy film with 100 mm lactic acid exhibits a slightly higher transmittance at ≈350–450 nm. The FeSxOy homostructure reveals average open‐circuit voltage (Voc) = 0.45 V, short‐circuit current (Jsc) = 0.0003 mA cm−2, fill factor =38%, and efficiency (η) = 0.57%. [ABSTRACT FROM AUTHOR]

The optimal process conditions concerning the hydrothermal carbonization of digested sewage sludge are crucial to the economically effective technology needed to produce a solid product, hydrochar, for energy purposes. Accordingly, different residence times, 0.5 h, 1 h and 2 h, were investigated in order to understand the effect of residence time on the process. Furthermore, the physical and chemical properties of hydrochar were investigated and compared to the raw material. For these reasons, analyses describing fuel properties were performed, including ultimate and proximate analyses, HHV, and TGA analysis. The latter method was employed to study the combustion process of solid samples. In addition, the oxide content of different elements within the ash of solid samples was determined using the XRF method to calculate indices related to operational problems during the combustion process. The results confirmed that time did not matter significantly and the physical and chemical properties of hydrochar were very similar to each other. However, the contact angle for 2 h of residence time confirmed that a longer processing time resulted in a more hydrophobic character of hydrochar and enabled more effective dewaterability of hydrothermal slurry. It was also noted that the hydrothermal carbonization process affected the sewage sludge in a positive way. In brief, the results confirmed that the hydrochar was a brittle, moderately hydrophilic, solid carbon-containing product that provided a different combustion performance than the raw sewage sludge. [ABSTRACT FROM AUTHOR]

Recent advances in materials science, device designs and advanced fabrication technologies have enabled the rapid development of transient electronics, which represents a class of devices or systems that their functionalities and constitutions can be partially/completely degraded via chemical reaction or physical disintegration over a stable operation. Therefore, numerous potentials, including zero/reduced waste electronics, bioresorbable electronic implants, hardware security, and others, are expected. In particular, transient electronics with biocompatible and bioresorbable properties could completely eliminate the secondary retrieval surgical procedure after their in-body operation, thus offering significant potentials for biomedical applications. In terms of material strategies for the manufacturing of transient electronics, silicon nanomembranes (SiNMs) are of great interest because of their good physical/chemical properties, modest mechanical flexibility (depending on their dimensions), robust and outstanding device performances, and state-of-the-art manufacturing technologies. As a result, continuous efforts have been made to develop silicon-based transient electronics, mainly focusing on designing manufacturing strategies, fabricating various devices with different functionalities, investigating degradation or failure mechanisms, and exploring their applications. In this review, we will summarize the recent progresses of silicon-based transient electronics, with an emphasis on the manufacturing of SiNMs, devices, as well as their applications. After a brief introduction, strategies and basics for utilizing SiNMs for transient electronics will be discussed. Then, various silicon-based transient electronic devices with different functionalities are described. After that, several examples regarding on the applications, with an emphasis on the biomedical engineering, of silicon-based transient electronics are presented. Finally, summary and perspectives on transient electronics are exhibited. [ABSTRACT FROM AUTHOR]

Unlike inorganic nanoparticles, organic nanoparticles (oNPs) offer the advantage of "interior tailorability," thereby enabling the controlled variation of physicochemical characteristics and functionalities, for example, by incorporation of diverse functional small molecules. In this study, a unique inimer-based microemulsion approach is presented to realize oNPs with enhanced control of chemical and mechanical properties by deliberate variation of the degree of hyperbranching or cross-linking. The use of anionic cosurfactants led to oNPs with superior uniformity. Benefitting from the high initiator concentration from inimer and preserved chain-end functionality during atom transfer radical polymerization (ATRP), the capability of oNPs as a multifunctional macroinitiator for the subsequent surface-initiated ATRP was demonstrated. This facilitated the synthesis of densely tethered poly(methyl methacrylate) brush oNPs. Detailed analysis revealed that exceptionally high grafting densities (~1 nm-2) were attributable to multilayer surface grafting from oNPs due to the hyperbranched macromolecular architecture. The ability to control functional attributes along with elastic properties renders this "bottom-up" synthetic strategy of macroinitiator-type oNPs a unique platform for realizing functional materials with a broad spectrum of applications. [ABSTRACT FROM AUTHOR]

The preservation of cultural heritage, particularly historical stone structures, represents a very challenging matter due to several environmental and anthropogenic factors. Vicenza stone, a calcareous rock known for its historical significance and widespread use in architectural masterpieces, requires significant attention for conservation. In fact, as the demand for sustainable and effective preservation methods intensifies, the exploration of innovative consolidation strategies becomes essential. To this end, inorganic consolidants, based on alkaline silicate formulations and nano-silica, were explored for their promising performance in enhancing the surface properties and chemical stability of Vicenza stone. In particular, the durability of treated and untreated Vicenza stone samples was evaluated by means of accelerated weathering tests such as freeze–thaw cycles, salt crystallization and simulation of acid rain. The experimental results revealed that Vicenza stone is very resistant to the effects of freeze–thaw cycles and acid rain; both the accelerated weathering tests did not show significant differences between treated and untreated VS samples. A different behavior was detected for the test for resistance to salt crystallization, whose findings led us to deduce that, for this kind of degradation, it is possible to observe a more beneficial effect of the consolidation treatments on the stone durability. [ABSTRACT FROM AUTHOR]

Utilizing Density Functional Theory (DFT) calculations at the B3LYP/QZVP level and incorporating the Conductor-like Polarizable Continuum Model (C-PCM) for solvation, the thermodynamic and chemical activity properties of 21-(hydroxymethoxy)henicosadecaenal, identified in cultured freshwater pearls from the mollusk Hyriopsis cumingii, have been elucidated. The study demonstrates that this compound releases formaldehyde, a potent antimicrobial agent, through dehydrogenation and deprotonation processes in both hydrophilic and lipophilic environments. Moreover, this polyenal exhibits strong anti-reductant properties, effectively scavenging free radicals. These critical properties classify the pearl-derived ingredient as a natural multi-functional compound, serving as a coloring, antiradical, and antimicrobial agent. The 2-(hydroxymethoxy)vinyl (HMV) moiety responsible for the formaldehyde release can be transferred to other compounds, thereby enhancing their biological activity. For instance, tyrosol (4-(2-hydroxyethyl)phenol) can be modified by substituting the less active 2-hydroxyethyl group with the active HMV one, and hinokitiol (4-isopropylotropolone) can be functionalized by attaching this moiety to the tropolone ring. A new type of meso-carrier, structurally modeled on pearls, with active substances loaded both in the layers and the mineral part, has been proposed. [ABSTRACT FROM AUTHOR]