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Exciton diffusion and carrier transport are two critical factors that determine the efficiency of organic photovoltaics (OPVs). However, the relationship between these two factors has not been extensively studied. Designing non‐fullerene acceptors (NFAs) with efficient diffusion coefficients and high electronic transmittance is a key area of focus. In this study, materials for bulk‐heterojunction (BHJ) and quasiplanar‐heterojunction (Q‐PHJ) devices are synthesized to validate the desired differences in crystallinity. The single crystal of BOBO4Cl‐βδ demonstrated the most compact packing structure, with an improved planar configuration and closer π···π distances, resulting in higher electron mobility and superior exciton diffusion coefficient. Consequently, BOBO4Cl‐βδ‐based devices achieved a power conversion efficiency (PCE) of 17.38% in Q‐PHJ, compared to a lower PCE of 14.75% in BHJ devices. Furthermore, incorporating BOBO4Cl‐βδ into the D18/L8‐BO Q‐PHJ system increased the PCE from 17.98% to 18.81%, one of the highest values recorded for Q‐PHJ devices. This improvement is attributed to strong crystallinity of BOBO4Cl‐βδ, which enhances the packing arrangement and improves the exciton diffusion coefficient. Our work highlights the importance of molecular design with tunable exciton diffusion and carrier transport for BHJ and Q‐PHJ OPV architectures and reveals the relationship between them, which contributes to the achievement of high‐performance NFAs. [ABSTRACT FROM AUTHOR]

Light Gradient Boosting Machine (LightGBM) and Random Forest (RF) algorithms were used to predict the apparent diffusion coefficient of Se(IV) in compacted bentonite. Seven instances of Se(IV) were measured using through-diffusion method. LightGBM (R2 = 0.98 and RMSE = 0.025) exhibited superior predictive accuracy with a training dataset consisting of 956 instances and eight input features from Japan Atomic Energy Agency (JAEA-DDB) and literatures. Shapley Additive Explanation and Partial Dependence Plots analyses revealed valuable insights into the diffusion mechanism of adsorbed anion obtained by evaluating the relationships between the apparent diffusion coefficient and the dependency of each input feature. [ABSTRACT FROM AUTHOR]

Electrolyte design is the optimal strategy to achieve extremely low temperature operation of lithium‐ion batteries. Here, the diffusion coefficient of Li+ is proposed to improve the ion transport kinetics at low temperatures. The diffusion coefficient of Li+ is improved by constructing a Li+ solvation sheath with weak steric effects. Specifically, high binding energy BF4− anions are added to a 1 M LiPF6 in propyl acetate (PA) electrolyte. Since the binding energy of Li+ with BF4− is greater than that of PA. Therefore, the small‐sized BF4− replaces the large‐sized PA molecule to form a Li+ solvation sheath with a weak steric effect, which increases the diffusion coefficient of Li+. Using the high diffusion coefficient electrolyte, the 800 mAh pouch cell retain 91 % and 75 % of its room temperature capacity at −40 °C(0.5 C rate) and −60 °C (0.2 C rate), respectively. And it also shows stable cycling at −40 °C. This work provides a new strategy for designing low‐temperature electrolytes of lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

AbstractKiln operators are forced to rely on their own experience and expertise when adapting standard drying schedules to tackle changing situations or to better suit their needs. The online tuning of a mechanistic model and its use as forward control is therefore proposed to address the current lack of tools. An inverse analysis of the drying kinetics of wooden boards dried in an industrial kiln is carried out to determine the moisture transfer properties of the boards. The values obtained by the inverse method are found to be relatively close to those obtained by direct measurement. The mechanistic model is then used with these input values to simulate the drying of a stack of boards to find the best drying strategy to meet the objectives. This work focuses on achieving a compromise between quality and time. Several difficulties were encountered in developing this approach for a semi-industrial dryer, and some recommendations are made for developing this innovative strategy further. [ABSTRACT FROM AUTHOR]

Molecularly crowded solutions have been used to simulate cytoplasmic fluids, but little justification is provided in the literature. This work compared three key physical properties of solutions containing polyethylene glycol and sucrose against those in the cytoplasmic fluid from bacteria Escherichia coli: fluid viscosity, relaxation time (T1 and T2) of water, and the diffusion coefficient of water. It was concluded that appropriate mixtures of sucrose and polyethylene glycol 10,000, such as 10% sucrose and 15% PEG10,000 and 7.5% sucrose and 19% PEG10,000, closely mimic these properties of cytoplasmic fluid from E. coli containing around 100 mg/mL of proteins. [ABSTRACT FROM AUTHOR]

The Young's modulus degradation of a biodegradable composite based on the exposure time to phosphate-buffered saline (PBS) solution was simulated by estimating the material's effective diffusion coefficient. The relationship between PBS uptake rate and material removal was investigated by comparing the finite element analysis and experimental results, and a criterion for the material removal of finite elements was proposed for an accurate material degradation simulation. The diffusion coefficient was calibrated to determine the best fit for the PBS uptake rate based on exposure time. The degradation behavior of a bone plate made of a fully biodegradable composite was analyzed using a calibrated diffusion coefficient; it was found that the screw hole parts were severely damaged owing to PBS uptake, which induced premature structural failure. To address this drawback, a hybrid bone plate composed of a nondegradable composite and a Mg wire/Polylactic acid (PLA) composite was introduced; its serviceability was verified using finite element analysis. [ABSTRACT FROM AUTHOR]

CO2 flooding plays a significant part in enhancing oil recovery and is essential to achieving CCUS (Carbon Capture, Utilization, and Storage). This study aims to understand the fundamental theory of CO2 dissolving and diffusing into crude oil and how these processes vary under reasonable reservoir conditions. In this paper, we primarily use molecular dynamics simulation to construct a multi-component crude oil model with 17 hydrocarbons, which is on the basis of a component analysis of oil samples through laboratory experiments. Then, the CO2 dissolving capacity of the multi-component crude was quantitatively characterized and the impacts of external conditions—including temperature and pressure—on the motion of the CO2 dissolution and diffusion coefficients were systematically investigated. Finally, the swelling behavior of mixed CO2–crude oil was analyzed and the diffusion coefficients were predicted; furthermore, the levels of CO2 impacting the oil's mobility were analyzed. Results showed that temperature stimulation intensified molecular thermal motion and increased the voids between the alkane molecules, promoting the rapid dissolution and diffusion of CO2. This caused the crude oil to swell and reduced its viscosity, further improving the mobility of the crude oil. As the pressure increased, the voids between the internal and external potential energy of the crude oil models became wider, facilitating the dissolution of CO2. However, when subjected to external compression, the CO2 molecules' diffusing progress within the oil samples was significantly limited, even diverging to zero, which inhabited the improvement in oil mobility. This study provides some meaningful insights into the effect of CO2 on improving molecular-scale mobility, providing theoretical guidance for subsequent investigations into CO2–crude oil mixtures' complicated and detailed behavior. [ABSTRACT FROM AUTHOR]

Ammonium dinitramide (ADN) is a new type of green energetic oxidizer with excellent energy density and low pollution combustion characteristics. However, the strong hygroscopicity has a significant impact on its practical application. To assist in the research on moisture-proof modification of ADN materials, an innovative hygroscopic modeling approach was proposed to evaluate the hygroscopicity of ADN at various temperatures and humidities. By investigating the diffusion coefficient of water molecules in molecular dynamics processes, a visual insight into the hygroscopic process of ADN was gained. Furthermore, analyzing the non-covalent interactions between ADN and water molecules, the hygroscopicity of ADN could be evaluated qualitatively and quantitatively. The energy analysis revealed that electrostatic forces play a dominant role in the process of water adsorption by ADN, whereas van der Waals forces impede it. As a whole, the simulation results show that ADN presents the following hygroscopic law: At temperatures ranging from 273 K to 373 K and relative humidity (RH) from 10% to 100%, the hygroscopicity of ADN generally shows an increasing trend with the rise in temperature and humidity based on the results of three simulations. According to the non-hygroscopic point (298 K, 52% RH) of ADN obtained by experiment in the literature, a non-hygroscopic range of temperature and humidity for ADN can be depicted when the simulation results in relative hygroscopicity is less than or equal to 17%. This study can provide effective strategies for screening anti-hygroscopic modified materials of ADN. [ABSTRACT FROM AUTHOR]

The diffusion of o-chlorotoluene (OCT), a hydrophobic organic compound, solubilized by means of the Triton X-100 surfactant from the region of local contamination into adjacent pure layers has been experimentally studied in a model kaolin based dispersion. The study is aimed at clarifying the factors influencing the motion of impurities in a dispersion medium with and without an electrical field. The theoretical analysis of obtained experimental data makes it possible to establish the effective diffusion coefficients of formed OCT/surfactant complexes in the pore space, which demonstrate the acceleration of the spread of contamination due to the influence of an electrical field. It has been shown that the diffusion coefficients of these complexes grow due to electroosmosis and hydrodynamic flows induced by it. Electroosmosis along negatively charged kaolin particles promotes the transport of impurities towards the cathode. At the same time, local narrowing of pores with a closed experimental cell leads to the pore solution hydrodynamic flows, which transport the impurities in the direction opposite to electroosmosis. Hence, due to a complicated interparticle space configuration, the electrical field actually results in pore solution mixing, which affects the character of the diffusion flows of impurities. Mixing may also be additionally intensified due to the heterogeneous charge of kaolin particles, which causes local changes in the direction of electroosmosis. At the same time, not only the fact of mixing as such is important, but also its specific features caused by different characters of electroosmotic and hydrodynamic flows and, correspondingly, by an sharp change in the direction of liquid flow near the surface of kaolin particles. As a consequence, the desorption of OCT/surfactant complexes from the surface of particles into the pore solution should be intensified and, correspondingly, the efficiency of their removal from the disperse systems should increase. [ABSTRACT FROM AUTHOR]

Multiple flow mechanisms that coexist in nanoscale porous media are responsible for deviations from the linear Klinkenberg equation. The use of mathematical models in the literature has obvious limitations in evaluating this flow phenomenon because the viscosity/diffusion coefficients of nanoscale porous media are more accurate only in the limited Knudsen number region. By introducing, the concept of an effective molecular mean free path, this paper proposes single models of viscosity/diffusion for the full Knudsen number range to replace the combination model in the literature. On this basis, a new apparent permeability model is developed with multiple coexisting mechanisms for the full Knudsen number range, and the effectiveness of the proposed model is verified by using published data. The discontinuous problem of the combination model of the viscosity/diffusion coefficient in the literature for the full Knudsen number range is solved using the new viscosity and diffusion coefficient models. The new apparent permeability model accurately predicts the absolute permeability and explains the phenomenon of deviation from the linear Klinkenberg equation. This paper further discusses the influence of different mechanisms on the permeability. The rarefaction effect weakens the diffusion ability in porous media but increases the contribution of Darcy flow to permeability. The viscous flow increment, absolute permeability and slippage effect were the most important flow mechanisms in nanopores. Article Highlights: We present the equation of the gas viscosity/diffusion coefficient in nanopores for the full Knudsen number range. We present a new apparent permeability model with multiple coexisting mechanisms for the full Knudsen number range. Our model predicts the absolute permeability of nanoscale porous media. [ABSTRACT FROM AUTHOR]

In this paper, we prove that under weak assumptions on the reaction terms and diffusion coefficients, a positive solution exists for a one-dimensional case and a positive radial solution to a multidimensional case of a nonlocal elliptic problem. Additionally, we establish the uniqueness of the solution, with the fixed point theorem being the primary tool employed. Our results are new and generalize several existing results. [ABSTRACT FROM AUTHOR]

A special setup was assembled to study solvent adsorption by metal organic frameworks (MOFs). A blank test was run to examine the noise level and the kinetic desorption curves for solvent molecules under different carrier gas (N2) flow rates were measured with the instrument error lying within a limited range. The desorption process could be adequately characterized by the transport of adsorbates in pores within MOFs. For the MOF samples NH2-MIL-101(Fe), HKUST-1, MIL-101(Cr), ZiF-67, and ZIF-8, the intercrystalline diffusion coefficient of ethanol, toluene, and propan-2-ol at 25, 35, and 45 °C were calculated and the activation energy was evaluated. The diffusion data obtained are in agreement with those reported earlier. [ABSTRACT FROM AUTHOR]

Zeolite 13X is an excellent candidate for the capture of CO2. However, this system needs to be investigated in more detail with regard to adsorption and diffusion. For this purpose, frequency response (FR) measurements were carried out with binderless zeolite 13X (NaMSX) and CO2. The size of the particles and the sample amount were modified in order to investigate their effects on diffusion processes. Macropore diffusion was detected and the corresponding diffusion coefficients were determined. The mentioned system was additionally used to evaluate the performance of the in‐house FR apparatus. [ABSTRACT FROM AUTHOR]

Efficiently breaking the oxide layer and rapidly diffusing of elements at low-temperature has been a longstanding goal in the diffusion bonding (DB) of Al alloys. To break the interfacial oxide layers and accelerate atomic diffusion, ultrasound energy was introduced during the DB of 6063Al. A full Zn–Al eutectoid joint was manufactured via a pure Zn interlayer at 360 °C in atmospheric by an ultrasonic-assisted diffusion bonding (U-DB) at only an ultrasonic vibration of10 min. During U-DB, brittle cracks were formed in the interfacial oxide layers due to high strain rate induced by ultrasonic action. Zn diffused into Al alloy through the brittle cracks in oxide layers via "subcutaneous diffusion," forming a Zn–Al eutectoid diffusion region between the Al alloy and oxide layer. The oxide fragments irregularly migrated to the center of the joint due to Kirkendall effect and ultrasonic action, finally dispersed in the bonded metal. The bonded metal finally transformed as a full Zn–Al eutectoid phase after consuming interlayer. The shear strength of the Zn–Al eutectoid joint reached 82.6 MPa. The Zn–Al mutual diffusion coefficient of U-DB at 360 °C was ∼0.6 μm2/s, which was about 20 times higher than the thermal diffusion coefficient under same temperature condition. Additionally, the mechanism of ultrasonic-assisted diffusion based on the strain-driven diffusion mode was discussed in detail. [ABSTRACT FROM AUTHOR]

In this study, a method based on chronoamperometry (CA) with a simple unshielded microwire electrode and macroelectrode was used to estimate the diffusion coefficient (D) of the electroactive species in molten chlorides without any knowledge of its concentration. Theoretically evaluated CA response ratios of the two electrodes were fitted to the values obtained from digital simulations and experiments within a measurement time of 1 s, and the D value was determined as a fitting parameter. Theoretical and experimental analyses of the CA response under pure diffusion-controlled conditions confirmed the applicability of the proposed method for the determination of D for any electroactive species, regardless of its reaction kinetics characteristics. The D values of Eu3+ and Cr2+ in molten LiCl–KCl at 450 ℃, which were determined from the CA of their reduction reactions and validated by simulations of the microwire electrode CA response, were consistent with previously reported values. However, the D of Cr2+ could not be accurately determined from the CA of its oxidation, possibly owing to the additional chronoamperometric current generated by the dissolution of the Au electrode. Therefore, the prevention of side reactions is vital for the accurate estimation of D. The proposed method could facilitate future research on molten salts and their properties. [ABSTRACT FROM AUTHOR]

The self-diffusion coefficients of carbonaceous fuels in a supercritical CO2 environment provide transport information that can help us understand the Allam Cycle mechanism at a high pressure of 300 atm. The diffusion coefficients of pure CO2 and binary CO2/CH4 and CO2/C2H6 at high temperatures (500 K~2000 K) and high pressures (100 atm~1000 atm) are determined by molecular dynamics simulations in this study. Increasing the temperature leads to an increase in the diffusion coefficient, and increasing the pressure leads to a decrease in the diffusion coefficients for both methane and ethane. The diffusion coefficient of methane at 300 atm is approximately 0.012 cm2/s at 1000 K and 0.032 cm2/s at 1500 K. The diffusion coefficient of ethane at 300 atm is approximately 0.016 cm2/s at 1000 K and 0.045 cm2/s at 1500 K. The understanding of diffusion coefficients potentially leads to the reduction in fuel consumption and minimization of greenhouse gas emissions in the Allam Cycle. [ABSTRACT FROM AUTHOR]

4Cr5Mo2V tooling steels are widely used in shaping of ferrous metals and non-ferrous metals. Present work aims to improve the hardness of gas carburization 4Cr5Mo2V die steels through modification of vanadium (V) content. 4Cr5M2V steels with mass fractions of 0.15% (V15), 0.55% (V55) and 1.25 wt.% (V125) of V were prepared and gas carburized. It was found that carburized 4Cr5Mo2V steels were covered by diffusion layers with thickness ranged from 500 to 900 μm. As content of V in 4Cr5Mo2V tooling steels increased, the diffusion layers (harder than matrix) also increased. Solid solution of V atoms in ferritic matrix played a positive role in decreasing the diffusion activation energy as well as in increasing the diffusion coefficient of carbon atoms. Model of gas carburization was constructed to predict the carbon concentration as a function of depth for Fe-C-V system. The predicted curves of carbon concentration were close to the measured values. [ABSTRACT FROM AUTHOR]

Background: The study's relevance is determined by the current desire to reduce the negative environmental impact of the textile industry. The study aims to develop and optimise dyeing processes using natural dyes in the textile industry. Results: The process of dye transfer from solution to Bombyx mori natural silk fibre can be divided into three successive kinetic stages. The first stage involves the adsorption of dye molecules on the active surface of the fibre, the second, their diffusion deep into the fibre towards its centre, and the third, the uniform distribution of dye molecules along the fibre starting from its centre. It is noticed that diffusion at the third stage slows down significantly, and the third stage lasts much longer than the first and second stages. The analysis of experimental data on dye concentration over time on dyed materials and their comparison with hypothetical data will make it possible to establish time intervals for each stage of the process and diffusion coefficients for each of them. Conclusion: This study has practical implications as it may contribute to more efficient and sustainable dyeing of textile materials using natural dyes, helping to reduce the negative environmental impact of the textile industry, and contributing to our knowledge of diffusion and dyeing processes. [ABSTRACT FROM AUTHOR]

This study investigates the local time diffusion coefficient for stable and unstable (ω = 0, ω = 0) states at the equator (00), "the geographical latitude where the first peak of the magnetic equatorial trough in the ionosphere occurs," during the spring and fall equinoxes (March 21 and September 23). The findings show that the diffusion tensor in a steady state is completely real and has a magnitude equal to the speed of light in a steady state. But in the unsteady state, the diffusion tensor consists of two parts, real and imaginary. The diagonal elements of the real part tensor are of the size of the conductivity in the ionosphere and the elements of the imaginary part are of the size of the speed of sound with about the same magnitude. Furthermore, for all assumed conditions, the diffusion elements form the first peak of the magnetic equatorial trough at 6.00 am local time. [ABSTRACT FROM AUTHOR]

Simple Summary: The human brain is still an enigma, and the relation between its physiology and function is still poorly understood. Advancements in quantum computations led to the hypothesis that neurons can also exercise quantum coherence, and a model for neuronal activity with quantum correlations appearing from the nuclei entanglement was proposed. However, whether such correlations can survive in a high-temperature biological environment to propagate through a neural network is still an open question. In this work, we examine one of the first steps in this process, the diffusion of neurotransmitters through the synaptic cleft, and show that, at least at this step, the correlations are persistent. Our results do not confirm the "quantum brain" hypothesis, but at least, they do not disprove it either, with studies on further steps needed. The "quantum brain" proposal can revolutionize our understanding of cognition if proven valid. The core of the most common "quantum brain" mechanism is the appearance of correlated neuron triggering induced by quantum correlations between ions. In this work, we examine the preservation of the correlations created in the pre-synaptic neurons through the transfer of neurotransmitters across the synaptic cleft, a critical ingredient for the validity of the "quantum brain" hypothesis. We simulated the transport of two neurotransmitters at two different clefts, with the only assumption that they start simultaneously, and determined the difference in their first passage times. We show that in physiological conditions, the correlations are persistent even if the parameters of the two neurons are different. [ABSTRACT FROM AUTHOR]

The electroanalytical behavior of SnSx (x = 1, 2) encapsulated into a carbon phase was studied using the galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS). These techniques are widely utilized in battery systems to investigate the diffusion of alkali metal cations in anode and cathode materials depending on the concentration of ions in the host material. Here, we report different calculation methods showing how the applied model affects the derived diffusion coefficient. The calculated value of the apparent chemical diffusion coefficient of sodium ions ( D N a + ) is in the range of 1 × 10−10 to 1 × 10−15 cm2/s depending on the technique, mathematical protocol, geometry of the electrode material, and applied potential. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures are prone to the corrosion of steel bars when exposed to chloride-rich environments, which can severely impact their durability. To address this issue, a comprehensive understanding of the factors influencing chloride ion diffusion in concrete is essential. This paper provides a summary of recent domestic and foreign research on chloride ion transport in concrete, focusing on six key factors: water–binder ratio, additive content, crack width, ambient temperature, relative humidity, and dry–wet cycles. The findings show that the diffusion coefficient of chloride ions in concrete increases with a higher water–binder ratio and decreases with increased additive content. Additionally, wider cracks result in a greater diffusion of chloride ions. The permeability resistance of concrete to chloride ions decreases with rising temperature and humidity, and dry–wet cycles further accelerate the diffusion of chloride ions. The article concludes by discussing various anti-corrosion measures, such as the use of corrosion inhibitors, surface coatings, and electrochemical treatments, to ensure the longevity of the structure. Finally, directions for future research are proposed. [ABSTRACT FROM AUTHOR]

In this paper, a novel non-convex fractional-order image denoising model is proposed to suppress the staircase effect produced by the TV model while maintaining a neat contour. The model combines ℓ q (0 < q < 1) quasi-norm and fractional-order regularization, and employs a diffusion coefficient with a faster convergence rate to preserve more image edges and details. Additionally, an adaptive regularization parameter is designed to adjust the denoising performance of the algorithm. To obtain the optimal approximate solution of the model, an enhanced primal-dual algorithm is adopted and the complexity and convergence of the algorithm are theoretically analyzed. Finally, the effectiveness of the proposed method is demonstrated through numerical experiments. • A new non-convex FOTV model is proposed. • A new diffusion coefficient is introduced to retain more edge details of the image. • The existing primal-dual algorithm is improved, and the convergence of this algorithm is analyzed. • An adaptive regularization parameter is designed. [ABSTRACT FROM AUTHOR]

The influence of grain size on the corrosion behavior of pure aluminum and the defect density and diffusion coefficient of surface passive films were investigated using electron backscatter diffraction (EBSD) and electrochemical testing techniques, based on the point defect model (PDM). Samples with three different grain sizes (23 ± 11, 134 ± 52, and 462 ± 203 μm) were obtained by annealing at different temperatures and times. The polarization curves and electrochemical impedance spectroscopy results for the pure aluminum in the 3.5% NaCl solution showed that with decreasing grain size, the corrosion current (icorr) decreased monotonously, giving rise to a noble corrosion potential and a large polarization resistance. The Motte–Schottky results showed that the passive films that formed on pure aluminum with fine grains of 23 ± 11 μm had a low density (3.82 × 1020 cm−3) of point defects, such as oxygen vacancies and/or metal interstitials, and a small diffusion coefficient (1.94 × 10−17 cm2/s). The influence of grain size on corrosion resistance was discussed. This work demonstrated that grain refinement could be an effective approach to achieving high corrosion resistance of passive metals. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the release of NH4-N and PO4-P from polymer-coated fertilisers in the soil environment, and to analyse their impact on pH and conductivity of the soil leachates. In this investigation mineral NPK(S) 6-20-30(7) fertiliser (as a starting material), commercial, controlled-release OsmocoteTM fertiliser (as a reference material) and four polymer-coated fertilisers have been used. Biodegradable polybutylene(succinate-codilinoleate), polyethylene(succinate-co-terepftalate) and chitosan have been used as coating materials. The experiments were conducted in the laboratory conditions, in PVC columns filled with air-dry soil. The nutrients release from the investigated materials was explained based on the diffusion mechanism and it was interpreted with the use of the Korsmeyer-Peppas kinetic model. Two mechanisms dominate in the release process of nutrients: the mechanism based on quasi-Fickian diffusion and non-Fickian (anomalous case) mechanism. The largest changes of pH and electrical conductivity (EC) of soil leachates occurred in the initial period of research for all tested fertilisers (pH: 9.5-20.3% - loamy sand (S1) 7.9-20.6% - sandy loam (S2); EC: 438-1667% - S1, 771-1509% - S2). The polymer coating significantly reduces the nutrient release from the fertiliser core. The size of these changes depends on the type and thickness of the polymer layer and the physicochemical properties of the soils. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are an excellent alternative solar cell technology that is cost-effective and environmentally friendly. The geometry, reactivity descriptors, light-harvesting efficiency, molecular radii, diffusion coefficient, and excited oxidation state potential of the proposed complex were investigated. The calculations in this study were performed using DFT/TDDFT method with B3LYP functional employed on the Gaussian 09 software package. The calculations were used the 6–311 + + G(d, p) basis set for the C, H, N, O, Cl atoms and the LANL2DZ basis set for the Re atom, with the B3LYP functional.. The balance of hole and electron in this complex has increased the efficiency and lifetime of DSSCs for photovoltaic cell applications. The investigated compound shows that the addition of the TPA substituent marginally changes the geometric structures of the 2, 2′-bipyridine ligand in the T1 state. As EDsubstituents were added to the compound, the energy gap widened and moved from ELUMO (− 2.904 eV) (substituted TPA) to ELUMO (− 3.122 eV) (unsubstituted). In the studying of solvent affects; when the polarity of the solvent decreases, red shifts appears in the lowest energy an absorption and emission band. Good light-harvesting efficiency, molecular radii, diffusion coefficient, excited state oxidation potential, emission quantum yield, and DSSC reorganization energy, the complex is well suited for use as an emitter in dye-sensitized solar cells. Among the investigated complexes mentioned in literature, the proposed complex was a suitable candidate for phosphorescent DSSC. [ABSTRACT FROM AUTHOR]

In this work, we have disclosed a facile metal-free synthesis of pharmaceutically fascinating and biologically important benzothiazepines in the presence of a few drops of ethanol. The present methodology converts chalcones and ortho -amino thiophenol into 2,3-dihydro-1,5-benzothiazepines under ambient conditions using liquid-assisted grinding, resulting in rapid synthesis in a very short period. This process is eco-friendly, operationally simple and gives good to excellent yields of products with easy isolation. This approach offers a facile synthesis of 2,3-dihydro-1,5-benzothiazepines from three readily available starting materials. An electrochemical study of the benzothiazepine derivatives was undertaken using cyclic voltammetry and electrochemical impedance spectroscopy techniques. This article introduces a metal-free, liquid-assisted grinding method for synthesising 2,3-dihydro-1,5-benzothiazepine systems. This protocol offers the benefits of non-hazardous reaction conditions, quick reaction times, tolerance to various functional groups and easy product isolation. It utilises the cost-effective tools of a mortar and pestle. Electrochemical techniques are also employed to determine the electrochemical properties and diffusion coefficients of 2,3-dihydro-1,5-benzothiazepine derivatives that can be helpful in their application in the pharmaceutical industry. This innovative approach shows promise for synthesising therapeutic derivatives and their applications. (Image credit: Manjit Singh.) [ABSTRACT FROM AUTHOR]

Diffusion processes in operations involving polymeric materials are of significant interest. Determining experimental values for diffusion coefficients is often challenging. Estimating these coefficients in concentrated polymer solution, polymer films, and membranes relies on experimental tests where the polymer is brought into contact with certain components/solvents. The diffusion coefficient values depend on the diffusion type, which is affected mainly by the nature of the polymer, concentration, and temperature. The literature presents an extensive amount of information regarding the diffusion phenomenon. This paper makes a particular contribution by showing how experimental data obtained from different applications can be processed to determine diffusion coefficients. The manuscript addresses some aspects regarding solvent diffusion in polymers, and illustrates how to determine the diffusion coefficients from experimental data. For specific cases of diffusion, several models for the predictive estimation of diffusion coefficients are also presented. Polymer–solvent systems such as polyvinyl alcohol (PVA)–water, cellulose acetate (CA)–tetrahydrofuran (THF) and cellulose triacetate (CTA)–dichloromethane (DCM) are investigated, with their diffusion mechanisms influenced by changes in structure caused by variations in concentration and temperature. The experimental data obtained through a gravitational technique allow for the highlighting of the diffusion mechanism and the selection of an appropriate mathematical model. A change in the structure of the polymer during the experiment leads to diffusion anomalies. Modeling the experimental data yielded diffusion coefficient values that vary based on the type of system investigated, composition and temperature. Thus, in the case of the CTA-DCM system, the diffusion coefficient at 303 K, at various concentration values, is in the range of 4.5 and 8·10−11 m2/s; for the PVA-H2O system, D = 4.1·10−12 m2/s at 303 K, and D = 6.5·10−12 m2/s at 333 K; while for the CA-THF system, the solvent–polymer diffusion coefficient has a value of 2.5∙10−12 m2/s at 303 K, and D = 1.75∙10−11 m2/s at 323 K. Mathematical models can be useful in studies regarding the drying of polymer films with complex structures, providing knowledge for designing or selecting suitable equipment. [ABSTRACT FROM AUTHOR]

In recent years, spatial atomic layer deposition (SALD) has gained significant attention for its remarkable capability to accelerate ALD growth by several orders of magnitude compared to conventional ALD, all while operating at atmospheric pressure. Nevertheless, the persistent challenge of inadvertent contributions from chemical vapor deposition (CVD) in SALD processes continues to impede control over film homogeneity, and properties. This research underscores the often-overlooked influence of diffusion coefficients and important geometric parameters on the close-proximity SALD growth patterns. We introduce comprehensive physical models complemented by finite element method simulations for fluid dynamics to elucidate SALD growth kinetics across diverse scenarios. Our experimental findings, in alignment with theoretical models, reveal distinctive growth rate trends in ZnO and SnO2 films as a function of the deposition gap. These trends are ascribed to precursor diffusion effects within the SALD system. Notably, a reduced deposition gap proves advantageous for both diffusive and low-volatility bulky precursors, minimizing CVD contributions while enhancing precursor chemisorption kinetics. However, in cases involving highly diffusive precursors, a deposition gap of less than 100 μ m becomes imperative, posing technical challenges for large-scale applications. This can be ameliorated by strategically adjusting the separation distance between reactive gas outlets to mitigate CVD contributions, which in turn leads to a longer deposition time. Furthermore, we discuss the consequential impact on material properties and propose a strategy to optimize the injection head to control the ALD/CVD growth mode. [ABSTRACT FROM AUTHOR]

The kinetic migration of poly(butylene succinate) (PBS) and poly(butylene succinate‐co‐adipate) (PBSA) biopolymers, prepared by cast film extrusion (thin film) and biaxial stretching (biaxially oriented [BO] film) techniques, were investigated based on experimental and mathematical modeling. MATLAB coding was used to fit the migration data to a diffusion model. BO films significantly reduced the migration rate compared with thin films, with reductions of 29% and 41% for BO‐PBS and BO‐PBSA, respectively, due to the increased degree of molecular crystallinity. Higher ethanol content increased the quantity of substance diffusing from plastic film. PBS and PBSA are more suitable for packaging hydrophilic foods than alcoholic beverages. PBS exhibited a lower migration rate than PBSA due to its more rigid polymer matrix. Remarkably, BO‐films exhibited 31% and 41% lower diffusion coefficients (D) compared with thin films, but significantly higher partition coefficients (KP,F) by 44% and 267% for BO‐PBS and BO‐PBSA, respectively. This suggests a stronger affinity of migrant for BO film matrix. However, at 70°C, PBSA films may be hydrolyzed with a high ethanol, resulting in an inadequate diffusion model. The diffusion–reaction concept should be implemented for a better fit. These findings provide valuable insights for selecting appropriate packaging materials and predicting migration under diverse conditions, ultimately promoting consumer safety. [ABSTRACT FROM AUTHOR]

It is well accepted that a lithiophilic interface can effectively regulate Li deposition behaviors, but the influence of the lithiophilic interface is gradually diminished upon continuous Li deposition that completely isolates Li from the lithiophilic metals. Herein, we perform in‐depth studies on the creation of dynamic alloy interfaces upon Li deposition, arising from the exceptionally high diffusion coefficient of Hg in the amalgam solid solution. As a comparison, other metals such as Au, Ag, and Zn have typical diffusion coefficients of 10–20 orders of magnitude lower than that of Hg in the similar solid solution phases. This difference induces compact Li deposition pattern with an amalgam substrate even with a high areal capacity of 55 mAh cm−2. This finding provides new insight into the rational design of Li anode substrate for the stable cycling of Li metal batteries. [ABSTRACT FROM AUTHOR]

In this research, the diffusion behaviors within the Ti-Fe-Cr ternary system were examined at the temperatures of 1273 K and 1373 K through the diffusion couple technique. This study led to the determination of both ternary inter-diffusion and impurity diffusion coefficients in the body-centered cubic (bcc) phase for the Ti-Fe-Cr alloy, utilizing the Whittle–Green and Hall methods. The statistics show that the average diffusion coefficients D ˜ F e F e T i and D ˜ C r C r T i measured at 1273 K were 1.34 × 10−12 and 3.66 × 10−13, respectively. At 1373 K, the average values of D ˜ F e F e T i and D ˜ C r C r T i were 4.89 × 10−12 and 1.43 × 10−12. By adopting the CALPHAD method, a self-consistent database for atomic mobility in the bcc phase of the Ti-Fe-Cr system was established. This database underwent refinement by comparing the newly acquired diffusion coefficients with data from the existing literature. Diffusion simulations for the diffusion couples were performed, drawing on the established database. The error between the simulated diffusion coefficient and the experimental measurement data is within 15%, and the simulated data of the component distance distribution and diffusion path are in good agreement with the experimental data. The simulations generated results that aligned well with the observed experimental diffusion characteristics, thereby affirming the reliability and accuracy of the database. [ABSTRACT FROM AUTHOR]

Several researches have been studied the diffusion coefficient (Da) of radionuclide in soil samples in varies location around the world; however, the effect of cations in groundwater as a medium of saturation for Cs-137 diffusion in soil and bentonite remains to be accomplished. Compacted soil and bentonite layers are utilized in the construction of radioactive waste disposal sites, which serve to prevent the release of Cs-137 from the repository to the unsaturated zone. The samples used were soil from the prospective disposal site in SP4—Serpong Nuclear Center (SNC) and bentonite taken from Santrijaya, Tasikmalaya. The diffusion coefficient (Da) is used as indicator of Cesium-137 diffusion in the samples. Experimental measurements were conducted on a diffusion column unit that varied in diffusion time and density conditions to determine diffusion coefficients. The samples were cut into slices and analyzed using Multichannel Analyzer (MCA) unit to measure Cs-137 radioactivity. The measurement results were then incorporated into Fick's Law equation to obtain the value of the diffusion coefficient (Da) of Cs-137 in soil and bentonite. The experimental results showed that the diffusion coefficients of samples with groundwater simulation are in the range of 10–12 m2 s−1 for the local soil and bentonite samples, respectively. Compare to the similar experiment that was conducted previously, the results indicated that the groundwater content could slightly impact the increase in the diffusion coefficient value of Cs-137. [ABSTRACT FROM AUTHOR]

The release of various pollutants into the environment necessitates monitoring their spreading in soils, developing strategies to prevent their transfer into water bodies, as well as identifying and conducting priority detoxification of those local contaminants that, due to their chemical and physical properties and the structure of polluted soils, pose the greatest risks. This article develops a theoretical theoretical basis and methodology for studying the diffusion transport of toxicants. Using a model dispersion of kaolin contaminated with o-chlorotoluene, the study investigates the diffusion rates of hydrophobic organic compounds in natural concentrated disperse systems. The experiments were conducted at various temperatures of the dispersion medium, both in the absence and presence of surfactant Triton X-100. A comparison was made between the temporal concentration distribution profiles of o-chlorotoluene in areas adjacent to the localized pollution zone and the results of theoretical calculations based on the Fick equation. Diffusion coefficients of the contaminant in the concentrated disperse system were calculated under the considered conditions of its spread. The obtained diffusion coefficients of o-chlorotoluene in the kaolin dispersion are significantly lower than the diffusion coefficients of organic hydrophobic compounds in aqueous media. This is attributed to the fine porosity of the model system used, the tortuosity of pores, and the interaction of o-chlorotoluene molecules with the dispersion surface. The structural factor and the presence of contact surface also contribute to a more pronounced reduction in the diffusion coefficient with decreasing temperature than would be expected due to the decrease in the energy of particle thermal motion and the increase in viscosity of the pore solution. The decrease in diffusion rate due to the formation of micellar aggregates of o-chlorotoluene with Triton X-100, caused by their larger sizes compared to individual molecules, is compensated by hydrophilization and the conversion of pollutants into a mobile state. [ABSTRACT FROM AUTHOR]

The pretreatment for peach drying is essential to enhance the efficiency of the drying process. This paper investigates the impact of various pretreatments (ethanol, ultrasound in water and ethanol, and microwave) on hot-air drying, microwave drying, and hot-air combined with microwaves (microwave finishing). Hot air drying revealed that ethanol pretreatment significantly reduced drying time by up to 23.5%, attributed to its osmotic effect and ability to dissolve food matrix constituents. Ultrasound pretreatment showed mixed results, with high amplitude (90%) and extended duration (30 min) yielding a 17.6% reduction in drying time. Microwave pretreatment demonstrated remarkable efficiency, reducing drying time by 58.8%, attributed to volumetric heating and steam flow induced by microwaves. Diffusion coefficients were calculated, with ethanol pretreatment exhibiting positive effects, while ultrasound and microwave pretreatments showed varying influences. Microwave drying post-pretreatment drastically reduced drying time, and the efficiency was further evaluated through microwave-finishing. Ethanol and ultrasound pretreatments improved final moisture content and drying rates during both drying stages, while microwave pretreatment resulted in severe overheating and quality loss. The scanning electron microscope images showed variations in the microstructure of the pretreated peach cubes compared to untreated ones. Ethanol pretreatment led to a more compact structure, while ultrasound pretreatment in water resulted in a porous structure. The combination of ethanol and ultrasound pretreatments exhibited more pronounced effects, particularly for hot air and microwave-finishing drying, where the cubes showed significant deterioration. [ABSTRACT FROM AUTHOR]

The choice of blowing agent is very important in foaming processes. In an earlier work the use of molecular dynamics simulations for the estimation of the diffusion coefficients of different blowing agents was discussed at elevated temperatures above the melting point. Therein it was shown that these simulations can give valuable information on blowing agent diffusion in polypropylene. The aim of the recent work is to expand this discussion to the simulation of different influences like pressure, blowing agent mixtures and blowing agents with higher molecular weight at temperatures above the melting point of PP. First a pressure range applied on the combined system of polymer and blowing agent, reasonable for the foam processing is discussed and their influence on the diffusion coefficients for CO2 in polypropylene is evaluated via MD simulations. The next step is the investigation of the influence of mixing a blowing agent with a co-blowing agent. The last part is the presentation of diffusion coefficients for different organic solvents, namely 2-propanol, acetone, ethyl acetate and butyl acetate which could be used as potential co-blowing agents. For both, the change in pressure and the mixing of blowing agents for the systems in question only small influences on the diffusion coefficients was discovered. The results of the diffusion coefficients for the different organic solvents are compared to each other and with former results, considered different molecular structure, size and polarities and are found to be reasonable. [ABSTRACT FROM AUTHOR]

The recent increased interest in structural health monitoring (SHM) related to material performance has necessitated the application of advanced data analysis techniques for interpreting the realtime data in decision-making. Currently, an accurate and efficient approach for the timely analyses of large volumes of uncertain sensor data is not well-established. This paper proposes an automated clustering-based piecewise linear regression (ACPLR)-SHM methodology for handling, smoothing, and processing large data sets. It comprises two main stages, where the gaussian weighted moving average (GWMA) filter is used to smooth noisy data obtained from electrical resistance sensors, and piecewise linear regression (PLR) predicts material properties for assessing the performance of concrete in service. The obtained values of stabilized resistance and derived values of diffusion coefficients using this methodology have clearly demonstrated the benefit of applying ACPLR to the sensor data, thereby classifying the performance of different types of concrete in service environments. [ABSTRACT FROM AUTHOR]

The Yungang Grottoes, one of China's most notable cultural heritage sites, are located in sandstone strata. The main causes of deterioration observed in the field are associated with moisture action, which greatly affects the long-term performance of the material. In particular, for immovable cultural heritage that is exposed to natural climatic fluctuations throughout the year, interaction with water vapor cannot be avoided. To obtain an insight into the water vapor transmission properties of local sandstone, a series of laboratory tests were conducted using the wet-cup method. The correlation of water vapor transmission with environmental relative humidity and pore structure was examined. The results indicate that as the relative humidity increased, the diffusion coefficient increased considerably due to the contribution of capillary condensate flow. In addition, a positive relationship was found between the diffusion coefficient and open porosity. The water vapor diffusion in sandstone occurred in transitory mode and the diffusion coefficient was estimated from the average pore radius. The calculated values were two orders of magnitude larger than those measured in the tests, reflecting the complex microstructural features concerning diffusion paths and area. The weathering processes constantly alter the sandstone's diffusion parameters, causing various damages in the Yungang Grottoes. [ABSTRACT FROM AUTHOR]

Model expressions are obtained for the concentration diffusion coefficient and thermal diffusion factor of a binary mixture obeying the Van der Waals equation of state. Model calculations at elevated pressure (density) require the equation of state parameters and thermal diffusion factor of the mixture in a low-density ideal gas state. The behavior of the model relations is studied as a function of pressure along isotherms. Near the critical state, the model diffusion coefficient has a minimum and the thermal diffusion coefficient has a maximum. The diffusion and thermal diffusion models at elevated pressure are compared with experimental data for a number of mixtures. It is shown that they are in qualitative and generally quantitative agreement at different temperatures and component concentrations. The Van der Waals equation is not quite suitable for describing experimental data on compressibility and phase equilibrium at high pressure. This requires more complex and flexible modifications of the equation. Generalized expressions are given for model diffusion characteristics of the binary mixture in the case of such equations of state. [ABSTRACT FROM AUTHOR]

As an important category of smart materials, stimuli-responsive hydrogels are highly concerned due to their extensive application possibilities and their outstanding biocompatibilities. The ability of responsive hydrogels about significant volume change by external stimuli inspires the design of electronic devices, for example, as sensors and actuators. The modeling of the hydrogel behavior enables the optimization of corresponding applications. In the present research, on the basis of the experimentally determined material parameters, a chemo-poromechanical model was implemented in COMSOL Multiphysics® to investigate the constricted swelling of hydrogels. The swelling kinetics affected by the diffusion coefficient is discussed in detail with numerical simulations. [ABSTRACT FROM AUTHOR]

Silicone rubber materials may be subject to mechanical strains which can affect the transport properties of small molecules loaded in the materials such as plasticizers and active molecules, hence deteriorating their intended mechanical properties or affecting their performance as carriers of active molecules. Therefore, it is important to understand the effects of mechanical strains on transport of small molecules in the silicone rubber matrix. In this work, silicone rubber sheets loaded with 2 wt% triacetin were stretched and held at four different lengths up to 125% engineering strain. The mass transfer coefficients and diffusion coefficients of triacetin in the strained silicone rubber were determined by monitoring the release of triacetin using headspace gas chromatography–mass spectrometry. It was found that there was no significant change of diffusion coefficient as the applied strain increased, which might result from two microstructure changes that had conflicting effects on diffusion: chain orientation and free volume deformation. [ABSTRACT FROM AUTHOR]

It is shown that the dynamics of changes in the state of nickel clusters depends on the temperature of the diffusion maximum and the cooling rate. It was found that with increasing annealing temperature and cooling rate, an increase in density and a decrease in cluster size are observed. In this case, the main attention was paid to the determination of the laws governing the change in the density, size, and structure of clusters from temperature and cooling. The process and dynamics of the interaction of clusters depends on the diffusion coefficient of impurity atoms in the lattice and the level of supersaturation of the solid solution. It has been established that with a change in the annealing temperature from T = 1100°C to 1250°C, the cluster density increases by almost 1-1.5 orders of magnitude, and their size decreases by a factor of 5-6. It seems to us that to obtain clusters with stable parameters, the optimal cooling rate is 200--300°C. [ABSTRACT FROM AUTHOR]

Detailed knowledge of the flow characteristics, bubble movement, and mass transfer is a prerequisite for the proper design of multiphase bioreactors. Often, mechanistic spatiotemporal models and computational fluid dynamics, which intrinsically require computationally demanding analysis of local interfacial forces, are applied. Typically, such approaches use volumetric mass-transfer coefficient (kLa) models, which have demonstrated their predictive power in water systems. However, are the related results transferrable to multiphase fermentations with different physicochemical properties? This is crucial for the proper design of biotechnological processes. Accordingly, this study investigated a given set of mass transfer data to characterize the fermentation conditions. To prevent time-consuming simulations, computational efforts were reduced using a force balance stationary 0-dimension model. Therefore, a competing set of drag models covering different mechanistic assumptions could be evaluated. The simplified approach of disregarding fluid movement provided reliable results and outlined the need to identify the liquid diffusion coefficients in fermentation media. To predict the rising bubble velocities uB, the models considering the Morton number (Mo) showed superiority. The mass transfer coefficient kL was best described using the well-known Higbie approach. Taken together, the gas hold-up, specific surface area, and integral mass transfer could be accurately predicted. [ABSTRACT FROM AUTHOR]

We use the Tyson-Fife model of the Belousov-Zhabotinsky reaction to numerically investigate the propagation of chemical reaction-diffusion waves through narrow, quasi-one-dimensional channels. We create soft obstacles in the form of activator and inhibitor diffusion coefficient inhomogeneities. Using a Fast Inhibitor Diffusion Region, in which the inhibitor's diffusion is larger than the activator's diffusion, the system can exhibit unidirectional propagation behavior - the diffusion diode. In a light-sensitive BZ-system, we discover a nonlinear compensation relationship between a higher activator diffusion (causing increased wave speed) and illumination (causing decreased wave speed) to achieve normal wave behavior. This enables the creation of a very energy efficient on/off-switch for chemical computation circuits in which a low intensity light pulse can be applied to a diffusion diode to disable wave propagation. [ABSTRACT FROM AUTHOR]

The thermochemical corrosion behaviour of different rare earth (RE)-based (Yb, Lu and Er) environmental barrier coatings (EBCs) between 1 and 48 h in low calcium–magnesium–aluminosilicate (CMAS) load environments at 1300 °C was studied. The EBCs were coated on reaction-bonded SiC–B 4 C substrates using the dip-coating method. Each coating is composed of a dense RE 2 SiO 5 -based bottom coat and a porous RE 2 O 3 topcoat. The microstructures and compositions of the corroded samples were examined using scanning electron microscopy and energy dispersive spectroscopy. CMAS infiltrated the topcoat through pores and cracks, settled in these defects, and dissolved in the neighbouring coating areas to precipitate as a Ca–Mg–Si–RE garnet. The diffusion coefficients of Ca and Si in the CMAS–EBC corroded specimens were calculated. Yb and Lu silicates have the lowest diffusion coefficient values, whereas Er silicate has the highest values. The formed garnet filled the pores and inhibited further diffusion of corrosive species in the coat. The corrosion rates were calculated based on the physical properties of the coat and found to be lower than those of coatings produced using atmospheric plasma spraying. The diffusion coefficient and corrosion rate were successfully used to evaluate various corrosion-resistant coatings. The results show that single-layer dip-coated Yb silicate is a cost-effective CMAS-resistant RE-based EBC. [ABSTRACT FROM AUTHOR]

A quadratic dependence of the charge diffusion coefficient on the diameter of colloidal quantum dots (CQDs) has been established. The charge diffusion coefficient is shown to depend weakly on the polydispersity of a sample. It has been determined that a decrease in the root-mean-square displacement of a charge carrier is an exponential function of the thickness of a ligand shell and the relative fraction of particles that can become charge traps. An explanation has been proposed for the exponential dependence of the conductivity of PbS CQD layers on the CQD size, which consists in a decrease in the fraction of CQDs acting as charge carrier traps. [ABSTRACT FROM AUTHOR]

In this paper, the influence of a chelating agent—diethylenetriaminepentaacetic acid (DTPA) on the anodic dissolution and cathodic deposition of indium was studied using electrochemical impedance spectroscopy (EIS), linear polarization (LP), and cyclic voltammetry (CV). Electrochemical impedance measurements demonstrate that the equivalent electrical circuit of the electrode/electrolyte interface includes both the Gerischer impedance and Warburg impedance, which explains the quasi-reversible kinetics, and the reaction mechanism is chemical-electrochemical. Results of linear polarization and impedance measurements demonstrate the decrease in polarization resistance of anodic dissolution of indium from 1.02 to 0.73 kΩ cm2 in the presence of DTPA in an alkaline medium. The activation energy of indium electrodeposition from the DTPA-containing electrolyte was determined from EIS data, demonstrating sluggish kinetics of the reaction, and the value of the activation energy was 62.1 kJ mol−1. Moreover, the high overpotential of indium electroreduction was confirmed by the decrease in the diffusion coefficient of indium ions from 2.9 × 10−7 to 1.4 × 10−7 cm2 s−1 in the presence of DTPA. The dimensionless current transients of indium electroreduction on platinum electrode show both instantaneous and progressive nucleation mechanisms depending on the applied potential, according to the Scharifker–Hills 3D nucleation model. The nucleation density and nucleation rate were 7.91 × 107 cm−2 at − 1.425V and 4.87 × 109 cm−2 s−1 at an applied potential of − 1.450 V, respectively. The results of this study may be useful for the electrochemical recovery of indium from indium tin oxide (ITO) waste. [ABSTRACT FROM AUTHOR]

Lithium–titanium–sulfur cathodes have gained attention because of their unique properties and have been studied for their application in lithium-ion batteries. They offer different advantages such as lower cost, higher safety, and higher energy density with respect to commonly adopted transition metal oxides. Moreover, this family of compounds is free from critical raw materials such as cobalt and nickel. For cathode materials, a crucial aspect is evaluating the evolution and behavior of the structure and properties during the cycling process, which means simulating the system under lithium extraction and insertion. Structural optimization, electronic band structures, density of states, and Raman spectra were simulated, looking for fingerprints and peculiar aspects related to the delithiation and overlithiation process. Lithium transport properties were also investigated through the nudged elastic band methodology. This allowed us to evaluate the diffusion coefficient of lithium, which is a crucial parameter for cathode performance evaluation. [ABSTRACT FROM AUTHOR]

The influence of diffusion on isothermal electroconvective flow of a low- conductivity fluid under unipolar injection in the constant electric field in a plane-parallel electrode system is studied. The dependences of the space charge density and flow fields on the diffusion intensity are obtained. The diffusion coefficient of injected ions is numerically estimated for TO + I2. The results obtained are based on comparison of the numerical experiment with the available experimental data. [ABSTRACT FROM AUTHOR]