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Most chemical processes happen at a local scale where only a subset of molecular orbitals is directly involved and only a subset of covalent bonds may be rearranged. To model such reactions, Density Functional Theory (DFT) is often inadequate, and the use of computationally more expensive correlated wavefunction (WF) methods is required for accurate results. Mixed-resolution approaches backed by quantum embedding theory have been used extensively to approach this imbalance. Based on the frozen density embedding freeze-and-thaw algorithm, we describe an approach to embed complete active space self-consistent field simulations run in the OpenMolcas code in a DFT environment calculated in CP2K without requiring any external tools. This makes it possible to study a local, active part of a chemical system in a larger and relatively static environment with a computational cost balanced between the accuracy of a WF method and the efficiency of DFT, which we test on environment–subsystem pairs. Finally, we apply the implementation to an oxygen molecule leaving an aluminum (111) surface and a ruthenium(IV) oxide (110) surface. [ABSTRACT FROM AUTHOR]

Chemical and physical processes on the surfaces of amorphous solids have been the focus of many studies over the past decades. These studies have established that dynamics in a thin layer near a glass surface are often dramatically faster than those in the glass bulk. Nevertheless, recent advances also emphasize the need for new experimental techniques capable of characterizing the structure and dynamics of the near-surface regions in glassy materials at the molecular length scale. Using a quasi-adiabatic fast scanning calorimetry (FSC) technique, we have investigated softening and vaporization of pure amorphous methylbenzene films of moderately heightened kinetic stability with thicknesses ranging from 1 to 20 nm. The analysis of the FSC thermograms reveals the existence of a high fictive temperature (liquid-like) layer on the surface of the solid glass with a thickness of 3.5 ± 0.5 nm or seven molecular diameters. Furthermore, the width of the boundary between liquid-like and solid layers in the films is less than 1 nm. These preliminary findings compliment and substantiate past determinations of the mobile surface layer thicknesses obtained by introduction of nanoparticles or spectroscopic molecular probes to near-surface regions of amorphous samples. The developed FSC methodology will advance the theoretical and computational research by providing calorimetric data on the enhanced interfacial dynamics phenomenon in a variety of low-molecular-weight amorphous materials. [ABSTRACT FROM AUTHOR]

Solid–water interfaces are crucial to many physical and chemical processes and are extensively studied using surface-specific sum-frequency generation (SFG) spectroscopy. To establish clear correlations between specific spectral signatures and distinct interfacial water structures, theoretical calculations using molecular dynamics (MD) simulations are required. These MD simulations typically need relatively long trajectories (a few nanoseconds) to achieve reliable SFG response function calculations via the dipole moment–polarizability time correlation function. However, the requirement for long trajectories limits the use of computationally expensive techniques, such as ab initio MD (AIMD) simulations, particularly for complex solid–water interfaces. In this work, we present a pathway for calculating vibrational spectra (IR, Raman, and SFG) of solid–water interfaces using machine learning (ML)-accelerated methods. We employ both the dipole moment–polarizability correlation function and the surface-specific velocity–velocity correlation function approaches to calculate SFG spectra. Our results demonstrate the successful acceleration of AIMD simulations and the calculation of SFG spectra using ML methods. This advancement provides an opportunity to calculate SFG spectra for complicated solid–water systems more rapidly and at a lower computational cost with the aid of ML. [ABSTRACT FROM AUTHOR]

Fast ion beams induce damage to deoxyribonucleic acid (DNA) by chemical products, including secondary electrons, produced from interaction with liquid water in living cells. However, the production process of these chemical products in the Bragg peak region used in particle therapy is not fully understood. To investigate this process, we conducted experiments to evaluate the radiolytic yields produced when a liquid water jet in vacuum is irradiated with MeV-energy carbon beams. We used secondary ion mass spectrometry to measure the products, such as hydronium cations (H3O+) and hydroxyl anions (OH−), produced along with ·OH radicals, which are significant inducers of DNA damage formation. In addition, we simulated the ionization process in liquid water by incident ions and secondary electrons using a Monte Carlo code for radiation transport. Our results showed that secondary electrons, rather than incident ions, are the primary cause of ionization in water. We found that the production yield of H3O+ or OH− was linked to the frequency of ionization by secondary electrons in water, with these electrons having energies between 10.9 and 550 eV. These electrons are responsible for ionizing the outer-shell electrons of water molecules. Finally, we present that the elementary processes contribute to advancing radiation biophysics and biochemistry, which study the formation mechanism of DNA damage. [ABSTRACT FROM AUTHOR]

Quantum dynamics simulation and computational spectroscopy serve as indispensable tools for the theoretical understanding of various fundamental physical and chemical processes, ranging from charge transfer to photochemical reactions. When simulating realistic systems, the primary challenge stems from the overwhelming number of degrees of freedom and the pronounced many-body correlations. Here, we present Kylin-V, an innovative quantum dynamics package designed for accurate and efficient simulations of dynamics and spectroscopic properties of vibronic Hamiltonians for molecular systems and their aggregates. Kylin-V supports various quantum dynamics and computational spectroscopy methods, such as time-dependent density matrix renormalization group and our recently proposed single-site and hierarchical mapping approaches, as well as vibrational heat-bath configuration interaction. In this paper, we introduce the methodologies implemented in Kylin-V and illustrate their performances through a diverse collection of numerical examples. [ABSTRACT FROM AUTHOR]

A hydrogen sensor is created on the basis of an acoustic topological material with a coiled structure. Compared to traditional hydrogen sensors, the sensor does not possess a sensitive layer and works with the shift of a topological interface state induced by hydrogen. The sensor is composed of two phononic crystals with distinct topological characteristics, and an interface state is achieved at the interface of both phononic crystals. When hydrogen is introduced into the sensor, the density and the sound velocity of the gas in the sensor change, which shifts the frequency of the interface state. Thus, the concentration of hydrogen can be obtained by measuring the frequency shift of the interface state. Due to the absence of a sensitive layer, the sensor operates without a chemical sorption process, and the performance of the sensor is marginally influenced by working conditions, temperature, and humidity. Theoretical analysis, numerical simulations, and experimental results show that in different background gases, synthetic air, nitrogen, and argon, the sensor exhibits relative sensitivities of 0.50, 0.50, and 0.37, which do not change with the working conditions. Additionally, the sensor possesses a rapid response, a good linearity and robustness, and a long lifespan. Furthermore, the sensor is designed based on a coiled structure, which considerably improves the space utilization and decreases the bulk. [ABSTRACT FROM AUTHOR]

Electron transfer reactions play an essential role in many chemical and biological processes. Fermi's golden rule (GR), which assumes that the coupling between electronic states is small, has formed the foundation of electron transfer rate theory; however, in short range electron/energy transfer reactions, this coupling can become very large, and, therefore, Fermi's GR fails to make even qualitatively accurate rate predictions. In this paper, I present a simple modified GR theory to describe electron transfer in the Marcus inverted regime at arbitrarily large electronic coupling strengths. This theory is based on an optimal global rotation of the diabatic states, which makes it compatible with existing methods for calculating GR rates that can account for nuclear quantum effects with anharmonic potentials. Furthermore, the optimal GR (OGR) theory can also be combined with analytic theories for non-adiabatic rates, such as Marcus theory and Marcus–Levich–Jortner theory, offering clear physical insights into strong electronic coupling effects in non-adiabatic processes. OGR theory is also tested on a large set of spin-boson models and an anharmonic model against exact quantum dynamics calculations, where it performs well, correctly predicting rate turnover at large coupling strengths. Finally, an example application to a boron-dipyrromethane–anthracene photosensitizer reveals that strong coupling effects inhibit excited state charge recombination in this system, reducing the rate of this process by a factor of 4. Overall, OGR theory offers a new approach to calculating electron transfer rates at strong couplings, offering new physical insights into a range of non-adiabatic processes. [ABSTRACT FROM AUTHOR]

Hydrated cation–π interactions at liquid–solid interfaces between hydrated cations and aromatic ring structures of carbon-based materials are pivotal in many material, biological, and chemical processes, and water serves as a crucial mediator in these interactions. However, a full understanding of the hydrated cation–π interactions between hydrated alkaline earth cations and aromatic ring structures, such as graphene remains elusive. Here, we present a molecular picture of hydrated cation–π interactions for Mg2+ and Ca2+ by using the density functional theory methods. Theoretical results show that the graphene sheet can distort the hydration shell of the hydrated Ca2+ to interact with Ca2+ directly, which is water–cation–π interactions. In contrast, the hydration shell of the hydrated Mg2+ is quite stable and the graphene sheet interacts with Mg2+ indirectly, mediated by water molecules, which is the cation–water–π interactions. These results lead to the anomalous order of adsorption energies for these alkaline earth cations, with hydrated Mg2+–π < hydrated Ca2+–π when the number of water molecules is large (n ≥ 6), contrary to the order observed for cation–π interactions in the absence of water molecules (n = 0). The behavior of hydrated alkaline earth cations adsorbed on a graphene surface is mainly attributed to the competition between the cation–π interactions and hydration effects. These findings provide valuable details of the structures and the adsorption energy of hydrated alkaline earth cations adsorbed onto the graphene surface. [ABSTRACT FROM AUTHOR]

Enhanced mixing in microfluidic systems is necessary in many applications such as chemical processing, biological assays, and diagnosis. We are developing a microfluidic system to efficiently mix minute reagents (down to several microliters) using vibration-induced flow (VIF), in which a net flow is generated around a micropillar by applying periodic vibration. In this study, we numerically investigate the enhancement in chaotic mixing using the VIF technique and periodic switching of vibrations. By extending our previous numerical simulation model, we investigate the flow field and trajectories of fluid particles in three-dimensional space. We demonstrate that chaotic advection characteristics can be observed by periodically switching the vibrational direction of a substrate using simple cylindrical pillars. In addition, using an appropriate interval for switching the vibration axes yields better mixing performance. The extent of chaotic advection is evaluated quantitatively using the Lyapunov exponent considering various vibration parameters, such as the vibration amplitude, separation distance between each pillar and pillar shape. The flow field induced by a large-amplitude and sharp-edged wall pillar provides excellent mixing results. Thus, VIF is successfully applied to obtain an efficient mixing strategy with the aid of the chaotic theory. [ABSTRACT FROM AUTHOR]

Solar fuels catalysis is a promising route to efficiently harvesting, storing, and utilizing abundant solar energy. To achieve this promise, however, molecular systems must be designed with sustainable components that can balance numerous photophysical and chemical processes. To that end, we report on the structural and photophysical characterization of a series of Cu(I)–anthraquinone-based electron donor–acceptor dyads. The dyads utilized a heteroleptic Cu(I) bis-diimine architecture with a copper(I) bis-phenanthroline chromophore donor and anthraquinone electron acceptor. We characterized the structures of the complexes using x-ray crystallography and density functional theory calculations and the photophysical properties via resonance Raman and optical transient absorption spectroscopy. The calculations and resonance Raman spectroscopy revealed that excitation of the Cu(I) metal-to-ligand charge-transfer (MLCT) transition transfers the electron to a delocalized ligand orbital. The optical transient absorption spectroscopy demonstrated that each dyad formed the oxidized copper–reduced anthraquinone charge-separated state. Unlike most Cu(I) bis-phenanthroline complexes where increasingly bulky substituents on the phenanthroline ligands lead to longer MLCT excited-state lifetimes, here, we observe a decrease in the long-lived charge-separated state lifetime with increasing steric bulk. The charge-separated state lifetimes were best explained in the context of electron-transfer theory rather than with the energy gap law, which is typical for MLCT excited states, despite the complete conjugation between the phenanthroline and anthraquinone moieties. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) is a crucial technique to prepare high-quality graphene because of its controllability. In the research, we perform a systematic computational fluid dynamics numerical investigation on the effect of gas-phase reaction dynamics on the graphene growth in a horizontal tube CVD reactor. The research results indicate that the gas-phase chemical reactions in the CVD reactor are in a nonequilibrium state, as evidenced by the comparison of species mole fraction distributions during the CVD process and under chemical equilibrium conditions. The effect of gas-phase reaction dynamics on the deposition rate of graphene under different conditions is studied, and our research shows that the main causes of change in graphene growth rates under different conditions are gas-phase reaction dynamics and active species transport. The results of numerical simulation agree well with the experimental phenomena. The research results also indicate that, for methane, the main limiting factor of graphene growth is the surface kinetic reaction rate. Conversely, for active species, the main limiting factor of graphene growth is species transport. Our research suggests that the growth rate of graphene can be regulated from the perspective of the gas reaction mechanism. This method has theoretical guiding significance and can be extended to the preparation of large-area graphene. [ABSTRACT FROM AUTHOR]

The technological landscape for industrial processes handling asphaltene is evolving at a rapid pace due to the increase in the extraction of heavy crude oil. The main underlying challenges in this regard are the flow assurance, the recovery of the spent solvent, and the sophisticated extractor setup required to develop the process to an industrial scale. The number of studies focused on the handling of the asphaltene at the atomic and molecular scales is growing enormously in order to identify new sustainable solvents for the effective extraction of asphaltene from heavy crude oil or oil-bearing sands. This Perspective focuses on the importance of density functional theory and molecular dynamics simulations to explore the broader range of asphaltene inhibitors, e.g., nanoparticles, ionic liquids, and deep eutectic solvents, to prevent asphaltene precipitation. We provide a concise overview of the major accomplishments, analyze the aspects that require attention, and highlight the path-breaking studies having a significant impact on the process of chemical enhanced oil recovery from heavy crude oil reservoirs primarily based on atomistic and molecular simulations. [ABSTRACT FROM AUTHOR]

Many important chemical processes involve reactivity and dynamics in complex solutions. Gaining a fundamental understanding of these reaction mechanisms is a challenging goal that requires advanced computational and experimental approaches. However, important techniques such as molecular simulation have limitations in terms of scales of time, length, and system complexity. Furthermore, among the currently available solvation models, there are very few designed to describe the interaction between the molecular scale and the mesoscale. To help address this challenge, here, we establish a novel hybrid approach that couples first-principles plane-wave density functional theory with classical density functional theory (cDFT). In this approach, a region of interest described by ab initio molecular dynamics (AIMD) interacts with the surrounding medium described using cDFT to arrive at a self-consistent ground state. cDFT is a robust but efficient mesoscopic approach to accurate thermodynamics of bulk electrolyte solutions over a wide concentration range (up to 2M concentrations). Benchmarking against commonly used continuum models of solvation, such as SMD, as well as experiments, demonstrates that our hybrid AIMD–cDFT method is able to produce reasonable solvation energies for a variety of molecules and ions. With this model, we also examined the solvent effects on a prototype SN2 reaction of the nucleophilic attack of a chloride ion on methyl chloride in the solution. The resulting reaction pathway profile and the solution phase barrier agree well with experiment, showing that our AIMD/cDFT hybrid approach can provide insight into the specific role of the solvent on the reaction coordinate. [ABSTRACT FROM AUTHOR]

Attempts to understand the molecular structure of water were first made well over a century ago. Looking back at the various attempts, it is illuminating to see how these were conditioned by the state of knowledge of chemistry and physics at the time and the experimental and theoretical tools then available. Progress in the intervening years has been facilitated by not only conceptual and theoretical advances in physics and chemistry but also the development of experimental techniques and instrumentation. Exploitation of powerful computational methods in interpreting what at first sight may seem impenetrable experimental data has led us to the consistent and detailed picture we have today of not only the structure of liquid water itself and how it changes with temperature and pressure but also its interactions with other molecules, in particular those relevant to water's role in important chemical and biological processes. Much remains to be done in the latter areas, but the experimental and computational techniques that now enable us to do what might reasonably be termed "liquid state crystallography" have opened the door to make possible further advances. Consequently, we now have the tools to explore further the role of water in those processes that underpin life itself—the very prospect that inspired Bernal to develop his ideas on the structure of liquids in general and of water in particular. [ABSTRACT FROM AUTHOR]

Time-resolved pump–probe and two-dimensional spectroscopy are widely used to study ultrafast chemical and biological processes in solutions. However, the corresponding signals at long times can be contaminated by molecular photothermal effects, which are caused by the nonradiative heat dissipation of photoexcited molecules to the surroundings. Additionally, molecular diffusion affects the transient spectroscopic signals because photoexcited molecules can diffuse away from the pump and probe beam focuses. Recently, a theoretical description of molecular photothermal effects on time-resolved IR spectroscopy was reported. In this work, I consider the molecular photothermal process, molecular diffusion, and sample flow to develop a generalized theoretical description of time-resolved spectroscopy. The present work can be used to interpret time-resolved spectroscopic signals of electronic or vibrational chromophores and understand the rate and mechanisms of the conversion of high-frequency molecular electronic and vibrational energy to solvent kinetic energy in condensed phases. [ABSTRACT FROM AUTHOR]

Metal hexafluorides hydrolyze at ambient temperature to deposit compounds having fluorine-to-oxygen ratios that depend upon the identity of the metal. Uranium-hexafluoride hydrolysis, for example, deposits uranyl fluoride (UO2F2), whereas molybdenum hexafluoride (MoF6) and tungsten hexafluoride deposit trioxides. Here, we pursue general strategies enabling the prediction of depositing compounds resulting from multi-step gas-phase reactions. To compare among the three metal-hexafluoride hydrolyses, we first investigate the mechanism of MoF6 hydrolysis using hybrid density functional theory (DFT). Intermediates are then validated by performing anharmonic vibrational simulations and comparing with infrared spectra [McNamara et al., Phys. Chem. Chem. Phys. 25, 2990 (2023)]. Conceptual DFT, which is leveraged here to quantitatively evaluate site-specific electrophilicity and nucleophilicity metrics, is found to reliably predict qualitative deposition propensities for each intermediate. In addition to the nucleophilic potential of the oxygen ligands, several other contributing characteristics are discussed, including amphoterism, polyvalency, fluxionality, steric hindrance, dipolar strength, and solubility. To investigate the structure and composition of pre-nucleation clusters, an automated workflow is presented for the simulation of particle growth. The workflow entails a conformer search at the density functional tight-binding level, structural refinement at the hybrid DFT level, and computation of a composite free-energy profile. Such profiles can be used to estimate particle nucleation kinetics. Droplet formation is also considered, which helps to rationalize the different UO2F2 particle morphologies observed under varying levels of humidity. Development of predictive methods for simulating physical and chemical deposition processes is important for the advancement of material manufacturing involving coatings and thin films. [ABSTRACT FROM AUTHOR]

Metal hexafluorides hydrolyze at ambient temperature to deposit compounds having fluorine-to-oxygen ratios that depend upon the identity of the metal. Uranium-hexafluoride hydrolysis, for example, deposits uranyl fluoride (UO2F2), whereas molybdenum hexafluoride (MoF6) and tungsten hexafluoride deposit trioxides. Here, we pursue general strategies enabling the prediction of depositing compounds resulting from multi-step gas-phase reactions. To compare among the three metal-hexafluoride hydrolyses, we first investigate the mechanism of MoF6 hydrolysis using hybrid density functional theory (DFT). Intermediates are then validated by performing anharmonic vibrational simulations and comparing with infrared spectra [McNamara et al., Phys. Chem. Chem. Phys. 25, 2990 (2023)]. Conceptual DFT, which is leveraged here to quantitatively evaluate site-specific electrophilicity and nucleophilicity metrics, is found to reliably predict qualitative deposition propensities for each intermediate. In addition to the nucleophilic potential of the oxygen ligands, several other contributing characteristics are discussed, including amphoterism, polyvalency, fluxionality, steric hindrance, dipolar strength, and solubility. To investigate the structure and composition of pre-nucleation clusters, an automated workflow is presented for the simulation of particle growth. The workflow entails a conformer search at the density functional tight-binding level, structural refinement at the hybrid DFT level, and computation of a composite free-energy profile. Such profiles can be used to estimate particle nucleation kinetics. Droplet formation is also considered, which helps to rationalize the different UO2F2 particle morphologies observed under varying levels of humidity. Development of predictive methods for simulating physical and chemical deposition processes is important for the advancement of material manufacturing involving coatings and thin films. [ABSTRACT FROM AUTHOR]

Initiating or sustaining physical and chemical transformations with mechanical force – mechanochemistry – provides an opportunity for more sustainable chemical processes, and access to new chemical reactivity. These transformations, however, do not always adhere to 'conventional' chemical wisdom, making them difficult to design and rationalise. This challenge is exacerbated by the fact that not all mechanochemical transformations are equal, with mechanical force playing a different role in different types of processes. In this review we discuss some of the different roles mechanical force can play in mechanochemical transformations, set primarily against the author's own research. We classify mechanochemical reactions broadly as those (1) where mechanical energy is for mixing, (2) where mechanical energy alters the stability of the reagent, and (3) where mechanical energy directly excites the solid. Finally, we demonstrate how – while useful – these classifications have fuzzy boundaries and concepts from across them are needed to understand many mechanochemical reactions. [ABSTRACT FROM AUTHOR]

Synthetic fibres cover most of the textile market, but their value chain is almost entirely linear. Common raw materials are non-renewable and oil-derived while requiring large amounts of (toxic) chemicals and energy for their processing into final products. In addition, synthetic textiles are usually non-biodegradable polymers; therefore, sustainable approaches for their depolymerisation into reusable monomers have not been implemented yet. As a result, most post-consumer synthetic textile waste ends up being landfilled, dispersed in the environment or incinerated, thus contributing significantly to global pollution. A possible solution to this issue is the design and use of advanced catalysts for their chemical recycling. This manuscript reviews the most significant approaches that appeared in the literature in the time span of 2015–2024, covering the selective depolymerisation process of synthetic waste textile to added-value reusable monomers using chemical catalysts. Unselective processes, for example, to produce fuel mixtures, biocatalytic methods and depolymerisation of polyolefins are not covered. The general aspects of the catalytic depolymerisation of synthetic polymers are briefly discussed, and the catalytic chemical recycling of synthetic textiles is detailed by the polymer type. While contributing to the overall achievement of the sustainable development goals, chemical recycling of synthetic textile waste may represent a useful strategy toward the circularity of the textile sector, which is almost unexplored. [ABSTRACT FROM AUTHOR]

Plant polysaccharides, as significant functional macromolecules with diverse biological properties, are currently receiving increasing attention. Drying technologies play a pivotal role in the research, development, and application of various foods and plant polysaccharides. The chemical composition, structure, and function of extracted polysaccharides are significantly influenced by different drying technologies (e.g., microwave, infrared, and radio frequency) and conditions (e.g., temperature). This study discusses and compares the principles, advantages, disadvantages, and effects of different drying processes on the chemical composition as well as structural and biological properties of plant polysaccharides. In most plant-based raw materials, molecular degradation, molecular aggregation phenomena along with intermolecular interactions occurring within cell wall components and cell contents during drying represent primary mechanisms leading to variations in chemical composition and structures of polysaccharides. These differences further impact their biological properties. The biological properties of polysaccharides are determined by a combination of multiple relevant factors rather than a single factor alone. This review not only provides insights into selecting appropriate drying processes to obtaining highly bioactive plant polysaccharides but also offers a fundamental theoretical basis for the structure–function relationship of these compounds. [ABSTRACT FROM AUTHOR]

In this study, new multilayer 3D porous scaffolds were designed with a core composed of Ca 3 O 5 Si (C 3 S) and external layers composed of Ca 5 Li 2 (PO 4) 4. Scaffolds' surface topography was modified to reveal a lamellar microstructure by applying chemical etching. Scaffolds were characterized by X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (FESEM/EDX), Fourier Transform Infrared Spectroscopy (FTIR) and Mercury Porosimetry. In vitro bioactivity was evaluated by immersing scaffolds in simulated body fluid (SBF) at 1, 3 and 7 days. Scaffolds presented calcium pyrophosphate, β-tricalcium phosphate (β-TCP), nonstoichiometric and stoichiometric calcium/lithium phosphate as the main phases. The calcium pyrophosphate and stoichiometric calcium/lithium phosphate in the external layer were eliminated by the chemical etching process, which revealed the lamellar microstructure. Lamellar width varied from 1.44 μm to 0.73 μm depending on the chemical etching time. The obtained mechanical strength results influenced samples' macroporosity, which ranged from 50 % to 64 %. These samples also exhibited microporosity between 30.3 % and 49.0 %. During the bioactivity test, all the chemically etched samples showed a hydroxyapatite-like (HA-like) precipitate, except for the sample chemically etched for 30 s at day 1. At day 7, the lamellar microstructure in the samples chemically etched for 30 s and 45 s (C-30 s and C-45 s) was completely covered by the HA-like precipitate, whereas the lamellar microstructure in the sample chemically etched for 60 s (C-60 s) was only partially covered by the HA-like precipitate. [Display omitted] [ABSTRACT FROM AUTHOR]

• A novel fluidized melting combustion has been proposed. • Combustion feasibility and performance has been evaluated by pilot-scale test. • Preheating stage efficiently achieved dehydration, preheating and crushing. • High temperature significantly enhanced decarbonization and slag captured rate. To address the issue of coal gasification fine slag (CGFS) disposal, a novel fluidized melting combustion (FMC) process has been proposed. In this study, the operating feasibility, combustion performance and gas pollutant emission were assessed through 0.4 MW pilot-scale test. The results indicated that both temperature and pressure fluctuation remained within the controllable range throughout entire test period. Under the influence of high cycle rate and incomplete combustion, CGFS efficiently achieved the rapid dehydration, preheating and crushing. Some combustible H 2 and CO were generated simultaneously. After the preheating modification, the refractory CGFS transformed into hot gas–solid composite fuel. To achieve the complete carbon removal and ash vitrification, the melting combustion temperature was up to 1501.1 °C. Under the excessively high temperature, liquid slag was discharged smoothly from the tap hole without any observed blockage. Carbon content in slag was only 0.4 wt%. The slag captured rate and decarbonization rate were up to 79.0 % and 93.8 %, respectively. The initial CO emission was as low as 103.0 mg/m3. The initial NO emission reached up to 452.5 mg/m3 under radiation boiler afterburning. Due to the combined influence of multiple factors, the initial SO 2 emission soared up to 1789.3 mg/m3. Further research will focus on controlling flue gas pollutant emissions, resource utilization of molten slag, and developing oxy-combustion. The objective is to attain full carbon neutrality in the entire coal chemical industry process. [ABSTRACT FROM AUTHOR]

This study was focused on the design and development of a new heterogeneous catalyst based on polyester (PE) fabric modified with graphene oxide nanosheets decorated with silver metallic nanoparticles (PE-rGO/Ag0), using a simple, easy, and effective approach. PE fabrics were coated by sonication with graphene oxide (GO) nanosheets followed by in situ deposition and reduction of silver nanoparticles over the GO surface, covering the PE fabric and producing PE-rGO/Ag0. The crystalline structure, surface morphology and chemical characteristics of the synthesised materials were identified by X-ray diffraction spectroscopy, scanning and transmission electron microscopy analyses (SEM and TEM) and by Fourier-transform infrared spectroscopy (FTIR), respectively. The catalytic performance of the prepared PE-rGO/Ag0 was assessed during the hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). Experimental results indicate that PE-rGO/Ag0 with a surface of 6 cm2 (3x2 cm) showed the highest catalytic activity with an apparent reaction rate constant (Kapp) of 0.65 min−1. In addition, PE-rGO/Ag0 activity resulted to be comparable and significantly higher than previously reported values of silver-based catalysts. Remarkable stability values were achieved during different operating cycles without significant degradation in the catalytic activity, suggesting that PE-rGO/Ag0 can be used as a strong candidate in long-lasting chemical catalytic processes. [ABSTRACT FROM AUTHOR]

This tutorial review provides a comprehensive overview of machine learning (ML)-based model predictive control (MPC) methods, covering both theoretical and practical aspects. It provides a theoretical analysis of closed-loop stability based on the generalization error of ML models and addresses practical challenges such as data scarcity, data quality, the curse of dimensionality, model uncertainty, computational efficiency, and safety from both modeling and control perspectives. The application of these methods is demonstrated using a nonlinear chemical process example, with open-source code available on GitHub. The paper concludes with a discussion on future research directions in ML-based MPC. [ABSTRACT FROM AUTHOR]

Nanofluids are the fluid suspensions in nanoparticles. A considerable enhancement in their features is less nanoparticle concentrations. Various studies on nanofluids focused on representing their performance with respect to the functions — here enhancing straight heat transfer was critical, like that in nuclear reactors, transportation, different industrial settings, biology, food and electronics. Hence, this consideration analyzes the utilization of the novel mathematical method, called the bvp4c method by viscous heat energy research in Buongiorno-modeled nanoliquid confined by the apt permeable plate along with slip mechanism. The thermophoresis and Brownian dispersion affects are again assumed. This transfer of solutal and thermal energy was dependent on the appreciable effect on heat source, variable chemical reactions and nonlinear thermal radiation. The dimensional model of partial differential equations (PDEs), applied to precise related applications, had been adapted into ordinary differential equations (ODEs). This modified Nusselt number decreases with increasing viscous heating, thermal radiation, thermophoresis parameter and Brownian motion, always it rises due to increasing temperature ratio parameter. The validation of the outcomes was attained with past solutions by free convectional flow and non-magnetic research. There are many functions in petroleum industries and engineering like electroplating, chemical processing of substantial metals and solar water heaters. [ABSTRACT FROM AUTHOR]

Supercritical CO2 (sc‐CO2) was widely used in CO2 flooding projects to enhance the recovery efficiency recently owing to its amazing dissolving capability and permeability. Fiber reinforced pipe (FRP) has exceptional properties that may be widely used in the petrochemical sector for transportation of corrosive fluid in CO2 flooding projects. In this research, a system was designed to simulate the transport behavior of fluids containing CO2 which can reaches the supercritical state by the adjustment of pressure and temperature. The fluid penetrates into the resin interior through the pores and gathers in the cavities at 65°C and 8 MPa. When the temperature and pressure are below the critical point, the CO2 volume expands dramatically, causing inter‐layered micro‐crack. When the environmental conditions repeatedly change above and below the critical point, these cracks will continue to propagate along the fiber arrangement direction, resulting in the fracture progressively grow into the delamination. At the same time, the fluid corrodes the resin in some areas of the surface, generating pitting and a 0.66% loss in resin content. The composition of elements and groups altered after corrosion revealed that a chemical interaction occurred between fluid and epoxy resin. Finally, due to physical and chemical processes produced by penetration, expansion, and dissolution, the stiffness of FRP fell by 3.53% during treatment. Highlights: In the present work, a reactor coated with polytetrafluoroethylene (PTFE) was built to model the corrosion of FRP in delivery fluids containing sc‐CO2. The corrosion mechanism was shown as a combination action by chemical react and physical behavior comprising penetration, expansion and dissolution.The physical corrosion mechanism of fluid containing sc‐CO2 was investigated. The fluid containing sc‐CO2 penetrated the FRP via pores and accumulated in cavities. The quick expansion of sc‐CO2 causes delamination while the ambient circumstances remain below the critical threshold. The pitting and resin loss can be linked to the epoxy resin solution in supercritical CO2.The chemical process, known as hydrolysis, took place on the interior surface of epoxy resin and a fluid containing supercritical CO2. This finally resulted in molecular structural modification. [ABSTRACT FROM AUTHOR]

Supercritical CO2 (sc‐CO2) was widely used in CO2 flooding projects to enhance the recovery efficiency recently owing to its amazing dissolving capability and permeability. Fiber reinforced pipe (FRP) has exceptional properties that may be widely used in the petrochemical sector for transportation of corrosive fluid in CO2 flooding projects. In this research, a system was designed to simulate the transport behavior of fluids containing CO2 which can reaches the supercritical state by the adjustment of pressure and temperature. The fluid penetrates into the resin interior through the pores and gathers in the cavities at 65°C and 8 MPa. When the temperature and pressure are below the critical point, the CO2 volume expands dramatically, causing inter‐layered micro‐crack. When the environmental conditions repeatedly change above and below the critical point, these cracks will continue to propagate along the fiber arrangement direction, resulting in the fracture progressively grow into the delamination. At the same time, the fluid corrodes the resin in some areas of the surface, generating pitting and a 0.66% loss in resin content. The composition of elements and groups altered after corrosion revealed that a chemical interaction occurred between fluid and epoxy resin. Finally, due to physical and chemical processes produced by penetration, expansion, and dissolution, the stiffness of FRP fell by 3.53% during treatment. Highlights: In the present work, a reactor coated with polytetrafluoroethylene (PTFE) was built to model the corrosion of FRP in delivery fluids containing sc‐CO2. The corrosion mechanism was shown as a combination action by chemical react and physical behavior comprising penetration, expansion and dissolution.The physical corrosion mechanism of fluid containing sc‐CO2 was investigated. The fluid containing sc‐CO2 penetrated the FRP via pores and accumulated in cavities. The quick expansion of sc‐CO2 causes delamination while the ambient circumstances remain below the critical threshold. The pitting and resin loss can be linked to the epoxy resin solution in supercritical CO2.The chemical process, known as hydrolysis, took place on the interior surface of epoxy resin and a fluid containing supercritical CO2. This finally resulted in molecular structural modification. [ABSTRACT FROM AUTHOR]

Chemistry traditionally relies on reactions in solution, but this method is increasingly problematic due to the scale of chemical processes and their economic and environmental impact. Handling residual chemical waste, including solvents, incurs significant costs and environmental pressure. Conversely, novel chemical approaches are needed to address pressing societal issues such as climate change, energy scarcity, food insecurity, and waste pollution. Mechanochemistry, a sustainable chemistry discipline that uses mechanical action to induce chemical reactivity without bulk solvents, is a hot topic in academic research on sustainable and green chemistry. Given its fundamentally different working principles from solution chemistry, mechanochemistry offers more efficient chemical processes and the opportunity to design new chemical reactions. Mechanochemistry has a profound impact on many urgent issues facing our society and it is now necessary to use mechanochemistry to address them. This Minireview aims to provide a guide for using mechanochemistry to meet the United Nations (UN) Sustainable Development Goals (SDGs), thereby contributing to a prosperous society. Detailed analysis shows that mechanochemistry connects with most UN SDGs and offers more cost‐efficiency than other approaches together with a superior environmental performance. [ABSTRACT FROM AUTHOR]

A bioinspired semisynthesis of human‐interleukin‐6 bearing N‐glycan at Asn143 (143glycosyl‐IL‐6) was performed by intentional glycosylation effects and protein folding chemistry for regioselective peptide‐backbone activation. 143Glycosyl‐IL‐6 is a genetically coded cytokine, but isolation was difficult owing to a tiny amount. IL6‐polypeptide (1–141‐position) with an intentionally inserted cysteine at 142‐position was expressed in E. coli. The expressed polypeptide was treated with a chemical folding process to make a specific helices bundle conformation through native two‐disulfide bonds (43–49 and 72–82). Utilizing the successfully formed free‐142‐cysteine, sequential conversions using cyanylation of 142‐cysteine, hydrazinolysis, and thioesterification created a long polypeptide (1–141)‐thioester. However, the resultant polypeptide‐thioester caused considerable aggregation owing to a highly hydrophobic peptide sequence. After the reduction of two‐disulfide bonds of polypeptide (1–141)‐thioester, an unprecedented hydrophilic N‐glycan tag was inserted at the resultant cysteine thiols. The N‐glycan tags greatly stabilized polypeptide‐thioester. The subsequent native chemical ligation and desulfurization successfully gave a whole 143glycosyl‐IL‐6 polypeptide (183‐amino acids). Removal of four N‐glycan tags and immediate one‐pot in vitro folding protocol efficiently produced the folded 143glycosyl‐IL‐6. The folded 143glycosyl‐IL‐6 exhibited potent cell proliferation activity. The combined studies with molecular dynamics simulation, semisynthesis, and bioassays predict the bioactive conformation of latent 143glycosyl‐IL‐6. [ABSTRACT FROM AUTHOR]

The accumulation of plastic waste is a severe environmental challenge worldwide. Although mechanical recycling methods are in place for plastics such as polyethylene terephthalate (PET), the physical and chemical properties are significantly compromised after a number of cycles, and they eventually reach end-of-life and end up in landfill. Chemical recycling is a collection of emerging innovative technologies that transform plastic waste into base chemicals, monomers and feedstocks. This approach complements mechanical recycling, bridging the gap between waste management and the petrochemical industry. However, with regard to the seven types of recyclable plastic, there is currently no clear overview of the suitable techniques. Therefore, we aim to provide a critical perspective on the suitability of different chemical processes towards recycling different types of plastic, by combining fundamental knowledge and research advancements in recent years, with an emphasis on assessing their environmental and economic impacts. Finally, based on the development status, we will highlight the current challenges and future opportunities in implementing chemical recycling technologies to meet the sustainability requirement of a climate-neutral circular economy. [ABSTRACT FROM AUTHOR]

The enormous potential of nanotechnology has drawn attention to many different fields. Using nanoparticles, bio-convection has become a key phenomenon in industrial and technical applications. Nanofluids have emerged as effective solutions for addressing complex heat transfer challenges in modern engineering. This study aims to develop a comprehensive three-dimensional model of Sutterby nanofluid flow with bio-convection, investigating the effects of nonlinear thermal radiation, gyrotactic microorganisms, and magnetic fields on thermal efficiency and entropy generation. By investigating entropy optimization, chemical processes, activation energy, viscous dissipation, and magnetic field effects, the research aims to improve Sutterby nanofluid efficiency. This model reveals the dynamics of Sutterby nanofluid behavior by using partial differential equations (PDEs) and successively converted into an ordinary differential equation (ODE) system. The converted equations are solved numerically using numerical technique bvp4c. The results of analyses show relationships between the concentration of nanofluid, Biot numbers, and microorganism profiles. The results indicate that while an increase in Biot number improves microorganism profiles, an increase in Lewis and Peclet numbers decreases nanofluid concentration. Critical elements that greatly affect mass distribution, heat transmission, and flow dynamics include magnetic fields, chemical processes, and activation energy. With the help of tables, the effects of physical parameters on skin friction, Nusselt numbers, and local Sherwood numbers are thoroughly investigated. [ABSTRACT FROM AUTHOR]

Lithium (Li) is becoming increasingly important due to its use in clean technologies that are required for the transition to net zero. Although acidophilic bioleaching has been used to recover metals from a wide range of deposits, its potential to recover Li has not yet been fully explored. In this study, we used a model Fe(II)- and S-oxidising bacterium, Acidiothiobacillus ferrooxidans (At. Ferrooxidans), to extract Li from three different minerals and kinetic modelling to predict the dominant reaction pathways for Li release. Bioleaching of Li from the aluminosilicate minerals lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) and spodumene (LiAl(Si2O6)) was slow, with only up to 14% (approximately 12 mg/L) of Li released over 30 days. By contrast, At. ferrooxidans accelerated Li leaching from a Li-bearing borosilicate clay (jadarite, LiNaB3SiO7OH) by over 50% (over 120 mg/L) in 21 days of leaching, and consistently enhanced Li release throughout the experiment compared to the uninoculated control. Biofilm formation and flocculation of sediment occurred exclusively in the experiments with At. ferrooxidans and jadarite. Fe(II) present in the jadarite-bearing clay acted as an electron donor. Chemical leaching of Li from jadarite using H2SO4 was most effective, releasing approximately 75% (180 mg/L) of Li, but required more acid than bioleaching for pH control. Kinetic modelling was unable to replicate the data for jadarite bioleaching after primary abiotic leaching stages, suggesting additional processes beyond chemical leaching were responsible for the release of Li. A new crystalline phase, tentatively identified as boric acid, was observed to form after acid leaching of jadarite. Overall, the results demonstrate the potential for acidophilic bioleaching to recover Li from jadarite, with relevance for other Li-bearing deposits. [ABSTRACT FROM AUTHOR]

Synthesis of value‐added chemicals from methane remains a great challenge due to its high energy requirement, low conversion efficiency, and unavoidable over‐oxidation of desired products. Here, the integration of a photon‐driven chemical cycle process with a continuous flow reactor over the Co0.2Pd1.8‐TiO2 catalyst has led to the continuous synthesis of C2H6 from CH4 with ≈100% selectivity under ambient conditions, simultaneously avoiding mixing flammable gas methane with O2 for the chemicals production. Such high selectivity and activity are due to the active lattice oxygen of PdOL and the oxygen‐lean condition characterized in the chemical cycle, together with Co single atoms for the regeneration of the photocatalyst surface during the chemical cycle process. The consumed oxygen in PdOL can be compensated by air during the subsequent catalyst regeneration process, leading to the stable activity during a 43 cycles test. Furthermore, this work to some extent demonstrates that the chemical cycle process not only improves the technoeconomic viability but also enhances safety of the process. [ABSTRACT FROM AUTHOR]

The environmental and health impacts of chemical processes have been a growing concern, leading to the establishment of Green Chemistry principles. Introducing new metrics for the assessment of methods' greenness is crucial to evaluate the exerted efforts to conserve the environment. In this work, we introduce a Modified Green Star Area (MoGSA) and software to assess the greenness of chemical reactions in laboratory settings. MoGSA refines the traditional Green Star Area Index (GSAI) by allowing users to selectively apply specific principles of Green Chemistry based on their relevance to the chemical process being evaluated. This approach addresses the limitations of GSAI, which often lacks clear boundaries between green and non-green practices and does not account for the varying applicability of the 12 Green Chemistry principles across different contexts. Through comparative case studies on catalytic stereoselective reduction of acetophenone, MoGSA demonstrates its utility in providing a more refined and flexible assessment, enhancing both educational and industrial applications of sustainable chemical practices. The software is available as an open source at https://bit.ly/MOGSA. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Time Period Major Taxa Studied Methods Results Main Conclusions To characterise the size and geometry of coral reefs on a global scale.Global.Present.Coral reefs.We process the Allen Coral Atlas database of shallow‐water tropical reefs to obtain a comprehensive and unprecedented inventory of coral reefs worldwide. We analyse different macroecological and morphological patterns, including size distribution, the area‐perimeter relationship, inter‐reef distance distribution, and the fractal dimension of individual reefs and coral provinces.We identified a total of 1,579,772 individual reefs worldwide (> 1000 m2), extending over a total of 52,423 km2 of ocean area with mean and median sizes of 3.32 and 0.3 ha, respectively. We unravelled three universal laws that are common to all coral reef provinces: the size‐frequency distribution and the inter‐reef distance distribution follow power laws with an exponent of 1.8 and 2.33, respectively. At the same time, the area‐perimeter relationship conforms to a power‐law with an exponent of 1.26. Furthermore, we demonstrate that coral reefs develop fractal patterns characterised by a perimeter fractal dimension of DP=1.3$$ {D}_P=1.3 $$ and a surface fractal dimension of DA=1.6$$ {D}_A=1.6 $$. Our analysis suggests that coral reefs tend to evolve from simple rounded filled shapes to more complex, elongated and less compact forms, developing into fractal structures with a consistent surface fractal dimension and an increasing perimeter fractal dimension as they grow.Coral reefs display intricate fractal‐like geometries and exhibit universal macroecological patterns, largely independent of their geographical location. The universality of the observed patterns suggests that these features possibly stem from the highly conserved interactions of biological, physical and chemical processes. Over geological scales, these processes lead to reef landscape patterns common among all provinces, providing new information relevant to reef growth modelling. [ABSTRACT FROM AUTHOR]

In this paper, within the framework of the Memory Functions Formalism, we study the dynamic features of the sequence of daily Wolf numbers. The effects of aftereffects and statistical memory, as well as dynamic intermittency, realized against the background of periodicity and cyclicity of solar activity, have been studied. Specific spatiotemporal structures of phase portraits of orthogonal dynamic variables, identified for maxima and minima of solar activity, were discovered, as well as predictors consisting of changes in the effects of statistical memory in periods preceding extremes. The results obtained complement the existing information on the dynamics of physical and chemical processes occurring in the solar atmosphere and convective zone. [ABSTRACT FROM AUTHOR]

The nickel metal hydride (NiMH) battery technology has been designed for use in electric vehicles, solar-powered applications and power tools. These batteries contain the critical and strategic raw materials cobalt, nickel and several rare earth elements (REE). When designing a battery recycling process, there are several choices to be made regarding end-products and process chemicals. The aim of this study is to investigate and compare the environmental and economic sustainability of different recycling options for NiMH batteries by taking projected market developments into consideration and by applying life cycle assessment and life cycle costing methods. The comparative study is limited to recovery of the REEs. Two hydrometallurgical processes for recovery of the REEs from the anode material are compared with extraction of REEs from primary sources in China. The processes compared are a high-temperature sulfation roasting process and a process based on hydrochloric acid leaching followed by precipitation of REE oxalates. By comparing the different recycling approaches, the hydrochloric acid process performs best. However, the use of oxalic acid has a large impact on the overall sustainability footprint. For the sulfation roasting process, the energy, sodium hydroxide and sulphuric acid consumption contribute most to the total environmental footprint. This article is part of the discussion meeting issue 'Sustainable metals: science and systems'. [ABSTRACT FROM AUTHOR]

Artificial intelligence has revolutionized various industries, including chemical process optimization. Artificial intelligence (AI) can be applied to various ethylene glycol (EG) production aspects to improve efficiency, quality, and overall process optimization. Process optimization of dimethyl oxalate (DMO) hydrogenation to ethylene glycol (EG) is carried out to minimize/maximize conversion, energy, productivity, bare module cost (CBM), and side product in the presence of pressure and temperature variables. A non-dominated sorting-based multi-objective neural network algorithm (MONNA) is applied to tackle problem optimization for EG production. The results show that the highest productivity, minimum energy cost, side product, and highest conversion are 172 Million RM/year, 0.00600 Million RM/year, 0.0320 kmol/hr, and 99.6%, respectively. The intermediate points in the Pareto Front PF for various three-objective situations provide lower energy costs than the bi-objective function. While bi-objective optimization might seem more straightforward, the intermediate points on the Pareto Front in three-objective optimization can provide lower energy costs due to more effective balancing of trade-offs, richer exploration of the solution space, capturing complex interdependencies, and offering more robust and flexible solutions. Decision makers can use the resulting pareto to decide on the most acceptable alternative according to their preferences. The decision variable plots show that the pressure highly affected the optimal solution with the opposite action. This work's analysis is predicted to provide insight into optimization literature for energy savings and sustainability and promote commercial growth for the industry. Identifying optimal trade-offs between various objectives, such as energy cost and productivity, can help reduce overall production costs, making the production process more competitive. [ABSTRACT FROM AUTHOR]

The incorporation of three distinct nanoparticles in blood within the context of cubic autocatalysis holds significant potential for enhancing biomedical applications, particularly in targeted drug delivery and therapeutic interventions. The increased reaction rate improves the efficiency of catalytic processes within the bloodstream. This research investigates the thermal transport characteristics of a trihybrid Carreau nanofluid (blood) containing copper (Cu), titanium dioxide (TiO2), and aluminum oxide (Al2O3), nanoparticles in the context of a wedge‐shaped artery under the influence of autocatalytic cubic autocatalysis. Effects of thermal radiation, and heat generation are used for heat transport analysis, heterogeneous‐homogeneous chemical process included for blood concentration, and an inclined magnetic field is imposed for securitization of blood velocity. Also, the generated PDEs from the physical model are handled through similarity transformations and converted into ODEs. Bvp4c, a numerical technique is used to get the solution and then Levenberg‐Marquardt neural network (LM‐NN), a multilayer neural network scheme is used to train and predict the solution for each parameter. In addition, the numerical values of volumetric friction of coefficients enhance the thermal conductivity, and the heat transport rate is increased. The magnetic parameter, radiation and chemical processes enhance the rate of heat transport while the Weissenberg number reduces the velocity profile. [ABSTRACT FROM AUTHOR]

The rapid expansion of photovoltaic (PV) installations across Mediterranean Europe since 2007 has resulted in a substantial increase in the need for end-of-life (EoL) management strategies for monocrystalline PV modules. This paper reviews the technical challenges and opportunities associated with the recycling of PV modules, focusing on the physical, chemical, and thermal processes currently employed. Despite advancements in recycling technology, significant gaps remain in infrastructure and regulatory enforcement, particularly in Mediterranean countries. The recovery of valuable materials such as silicon, silver, and glass presents both economic and environmental benefits, although the costs of recycling remain a key barrier to widespread adoption. Our analysis suggests that optimizing these recycling processes could improve their profitability and scalability, enabling more effective resource recovery. The paper concludes with recommendations for policy and infrastructure development to support the sustainable management of PV waste across the Mediterranean region. [ABSTRACT FROM AUTHOR]

Chemical dissolution along interfaces between solid skeleton and pore fluids tends to alter geomaterials and may cause catastrophic failures. Following the hydrodynamic procedure, this work develops a mathematically rigorous and thermodynamically consistent modelling framework to investigate the impact of chemo-mechanical coupling on the constitutive properties of poroelastic geomaterials. The formulation considers the mass fractions of all the ionic species in the pore fluid as independent state variables that quantify chemical processes. The constitutive and transport relationships are systematically derived from thermodynamic principles, symmetry requirements and conservation laws. To demonstrate its effectiveness, the formulation is adopted to study the dissolution process of saturated calcarenites under acidic environments. Simple density-dependent linear elasticity is being considered whereby stiffness degradation is physically captured in terms of density changes. Without chemical reaction, the stiffness is fixed and the response is purely linearly 'poroelastic'. However, upon reaction the density changes, and thus so also does the stiffness, implying a non-linear response. The model also reveals the connection of densities to chemical potentials and pore fluid pressure, and shows that the latter quantity is governed by both density and osmotic concentration. Simulations of long-term debonding tests of calcarenite samples show good agreement with experimental observations under both uncoupled and coupled testing conditions. Furthermore, considering only a limited number of clearly stated assumptions, the model recovers the form of several empirical laws such as Darcy's law, Fick's law and the law of reaction kinetics. Outside these idealised model assumptions, the newly derived relationships generalise results for field conditions and provide insights into cases where one normally does not have, or technologically cannot reliably obtain experimental data due to challenging loading and boundary conditions. [ABSTRACT FROM AUTHOR]

In this paper, PHREEQC software was used to calculate the saturation index of insoluble minerals, the pH boundary values of precipitated CaCO3, and the boundary values of Ca2+ and HCO3− concentrations in relation to the uranium extraction process and the chemical composition of leaching in the Nalinggou uranium deposit. Based on the comparative analysis results of the mineral composition and chemical composition of the primary rock and the blockage, the formation of the blockage containing the mineral layer is mainly related to the pH-value and the corresponding ion concentration of the leaching solution, the sediment can be effectively avoided in the boundary value range. [ABSTRACT FROM AUTHOR]

The article discusses the challenges and opportunities in sustainable medicines development and use, focusing on the sustainable production of active pharmaceutical ingredients (APIs). It emphasizes the importance of minimizing the environmental impact of medicine production and highlights the use of lifecycle assessment (LCA) to quantify environmental impacts. The article also addresses the sustainability challenges in small molecule APIs and biological APIs, such as monoclonal antibodies, and explores strategies like solvent recycling and continuous bioprocessing to reduce environmental impact. Overall, the pharmaceutical industry is increasingly focusing on sustainability improvements and collaborating to address environmental issues in medicine production. [Extracted from the article]

The description of the new version of the INM–RSHU chemistry–climate model, created on the basis of the climate model INMCM6.0 is presented. A special feature of the new version of the chemistry–climate model is the complete unification of the model structure with the basic core of the INMCM6.0 climate model. The transport of chemically active species in the atmosphere is performed on the same grid and by the same methods as the transport of meteorological parameters and aerosol. Chemical transformations are added as local processes at each grid point of the model, correcting the changes in tropospheric and stratospheric concentrations of chemically active species caused by dynamical processes. The model was tested using the results of calculations of changes in the chemical composition of the atmosphere over the last 20 years of the 20th century, performed with a version of the model with a resolution of 4 × 5 degrees in latitude and longitude. [ABSTRACT FROM AUTHOR]

Saltwater stands as the most prevalent liquid on Earth. Consequently, substantial interest has been directed toward its characterization, both as an independent system and as a solvent for complex structures such as biomacromolecules. In the last few decades, special emphasis was placed on the investigation of the hydration properties of ions for the fundamental role they play in numerous chemical processes. In this study, we employed multi-wavelength Raman spectroscopy to examine the hydration shell surrounding bromide ions in solutions of simple electrolytes, specifically lithium bromide, potassium bromide, and cesium bromide, at two different concentrations. Cation-induced differences among electrolytes were observed in connection to their tendency to form ion pairs. An increased sensitivity to reveal the structure of the first hydration shell was evidenced when employing ultraviolet excitation in the 228–266 nm range, under resonance conditions with the charge transfer transition to the solvent peaked at about 200 nm. Other than a significant increase in the Raman cross-section for the OH stretching band when shifting from pure water to the solution, a larger enhancement for the Raman signal of the H–O–H bending mode over the stretching vibration was observed. Thus, the bending band plays a crucial role in monitoring the H-bond structure of water around the anions related to the charge distribution within the first hydration shell of anions, being an effective probe of hydration phenomena. [ABSTRACT FROM AUTHOR]

Coming to terms with climate change by understanding climate processes and their policy implications is essential not only for climate scientists and policymakers, but also for the general public, for industrial practitioners, and for engineers, including process system engineers. We have developed a simplified linear climate model (SLCM) to enable non‐specialists to explore the essential physical and chemical processes caused by greenhouse gas emissions. Trading‐off simplicity and accuracy, achieved by calibrating model parameters using established simple climate models, the SLCM allows (i) determining the climate impact of given past and future emissions, (ii) determining the amounts of CO2 removal needed to compensate for any unavoidable emissions of CH4 and N2O from agriculture, and (iii) back‐calculating emission pathways to meet specified global warming targets. [ABSTRACT FROM AUTHOR]

The kinetics of the leaching of natural magnesite with hydrochloric or nitric acid has been studied. Relatively high values of the apparent activation energy (from 46.5 to 70.0 kJ mol−1), but especially the low values of the apparent reaction order for H+ cations, $n$ n , have shown that the whole process is controlled by the surface chemical reaction. The value of $n$ n decreases continuously with increasing activity of H+ cations in the range of pH 5 to −1.4. At ${\rm{pH}}\,\lt 2.6$ pH < 2.6 there is a transition from the kinetic regime characterized by $n \cong $ n ≅ 0.5 to another one with $n$ n close to zero. [ABSTRACT FROM AUTHOR]

Every year, a huge amount of lethal compounds, such as synthetic dyes, pesticides, pharmaceuticals, hydrocarbons, etc. are mass produced worldwide, which negatively affect soil, air, and water quality. At present, pesticides are used very frequently to meet the requirements of modernized agriculture. The Food and Agriculture Organization of the United Nations (FAO) estimates that food production will increase by 80% by 2050 to keep up with the growing population, consequently pesticides will continue to play a role in agriculture. However, improper handling of these highly persistent chemicals leads to pollution of the environment and accumulation in food chain. These effects necessitate the development of technologies to eliminate or degrade these pollutants. Degradation of these compounds by physical and chemical processes is expensive and usually results in secondary compounds with higher toxicity. The biological strategies proposed for the degradation of these compounds are both cost-effective and eco-friendly. Microbes play an imperative role in the degradation of xenobiotic compounds that have toxic effects on the environment. This review on the fate of xenobiotic compounds in the environment presents cutting-edge insights and novel contributions in different fields. Microbial community dynamics in water bodies, genetic modification for enhanced pesticide degradation and the use of fungi for pharmaceutical removal, white-rot fungi's versatile ligninolytic enzymes and biodegradation potential are highlighted. Here we emphasize the factors influencing bioremediation, such as microbial interactions and carbon catabolism repression, along with a nuanced view of challenges and limitations. Overall, this review provides a comprehensive perspective on the bioremediation strategies. [ABSTRACT FROM AUTHOR]

Biogenic volatile organic compounds are emitted by plants and influence human and environmental health. They contribute to the formation of pollutants such as ozone and secondary organic aerosols, thereby influencing air quality and climate. Here we review biogenic volatile organic compounds with focus on biosynthesis, release to the atmosphere, distribution at various scales, tropospheric chemical processes, and secondary organic aerosols. Biogenic volatile organic compounds are emitted primarily through enzymatic pathways in response to environmental factors, varying across plant species and ecosystems. These emissions exhibit heterogeneity at multiple scales, influenced by meteorological conditions and plant structure. [ABSTRACT FROM AUTHOR]