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Aromatic sensitizers and related substances (SRCs), which are crucial in the paper industry for facilitating color‐forming and color‐developing chemical reactions, inadvertently contaminate effluents during paper recycling. Owing to their structural resemblance to endocrine‐disrupting aromatic organic compounds, concerns have arisen about potential adverse effects on aquatic organisms. We focused on SRC effects via the aryl hydrocarbon receptor (AHR), employing molecular docking simulations and zebrafish (Danio rerio) embryo exposure assessments. Molecular docking revealed heightened binding affinities between certain SRCs in the paper recycling effluents and zebrafish Ahr2 and human AHR, which are pivotal components in the SRC toxicity mechanism. Fertilized zebrafish eggs were exposed to SRCs for up to 96 h post fertilization; among these substances, benzyl 2‐naphthyl ether (BNE) caused morphological abnormalities, such as pericardial edema and shortened body length, at relatively low concentrations (1 μM) during embryogenesis. Gene expression of cytochrome P450 1A (cyp1a) and ahr2 was also significantly increased by BNE. Co‐exposure to the AHR antagonist CH‐223191 only partially mitigated BNE's phenotypic effects, despite the effects of 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin being relatively well restored by CH‐223191, indicating BNE's AHR‐independent toxic mechanisms. Furthermore, some SRCs, including BNE, exhibited in silico binding affinity to the estrogen receptor and upregulation of cyp19a1b gene expression. Therefore, additional insights into the toxicity of SRCs and their mechanisms are essential. The present results provide important information on SRCs and other papermaking chemicals that could help minimize the environmental impact of the paper industry. Environ Toxicol Chem 2024;43:2176–2188. © 2024 SETAC [ABSTRACT FROM AUTHOR]

Capturing short‐lived intermediates at the molecular level is key to understanding the mechanism and dynamics of chemical reactions. Here, we have developed a paper‐in‐tip bipolar electrolytic electrospray mass spectrometry platform, in which a piece of triangular conductive paper incorporated into a plastic pipette tip serves not only as an electrospray emitter but also as a bipolar electrode (BPE), thus triggering both electrospray and electrolysis simultaneously upon application of a high voltage. The bipolar electrolysis induces a pair of redox reactions on both sides of BPE, enabling both electro‐oxidation and electro‐reduction processes regardless of the positive or negative ion mode, thus facilitating access to complementary structural information for mechanism elucidation. Our method enables real‐time monitoring of transient intermediates (such as N,N‐dimethylaniline radical cation, dopamine o‐quinone (DAQ) and sulfenic acid with half‐lives ranging from microseconds to minutes) and transient processes (such as DAQ cyclization with a rate constant of 0.15 s−1). This platform also provides key insights into electrocatalytic reactions such as Fe (III)‐catalyzed dopamine oxidation to quinone species at physiological pH for neuromelanin formation. [ABSTRACT FROM AUTHOR]

Rationale: Paper spray (PS) is a simple and innovative ambient ionization technique for mass spectrometry (MS) analysis. Under PS‐MS conditions, chemical reactions, which usually occur slowly on a bulk scale, are accelerated. Moreover, the formation of products and transient species can be easily monitored. In this manuscript, reactions between phthalic anhydride and diamines were conducted and monitored using a PS‐MS platform. The reaction products (phthalimides) have many pharmaceutical applications, but their traditional syntheses can take hours under reflux, requiring laborious purification steps. Methods: In situ reactions were performed by dropping methanolic solutions of phthalic anhydride and diamines on a triangular paper. The analyses were achieved by positioning the triangle tip in front of the mass spectrometer entrance, whereas a metal clip was attached to the triangle base. After adding methanol to the paper, a high voltage was applied across the metal clip, and the mass spectra were acquired. Results: The intrinsic reactivity of alkyl and aromatic diamines was evaluated. The carbon chain remarkably influenced the reactivity of aliphatic diamines. For aryl diamines, the ortho isomer was the most reactive. Moreover, for aryl amines with electron‐withdrawing substituents, no reaction was noticed. Conclusions: Taking advantage of the unique characteristics of PS‐MS, it was possible to investigate the intrinsic reactivity of model alkyl (ethylene versus propylene) and aryl (o‐phenylene versus m‐phenylene and p‐phenylene) diamines towards phthalic anhydride. Some crucial parameters that affect the intrinsic reactivity of organic molecules, such as isomerism, intramolecular interaction, and conformation, were easily explored. [ABSTRACT FROM AUTHOR]

High‐barrier performance, especially under extreme working conditions, is the key to replacing other types of packaging materials with paper‐based materials. In this paper, two biomass‐based polymers, sodium alginate (SA), and chitosan, were used to form a barrier coating with silicone emulsions to prepare a high‐performance paper‐based barrier material. By double coating, the water and oilproof functions were superimposed. The two prepared coated papers were characterized by infrared spectroscopy analysis, contact angle test, and scanning electron microscopy analysis, while their water resistance, oil resistance, thermal oil resistance, and thermal stability were tested. The water and oil repellency were achieved by double coating. The Cobb value of the chitosan‐silicone emulsion‐coated paper reached 5.3 g/m2, with a Kit grade of Level 12, and could block the penetration of castor oil at 80°C within 24 h. The Cobb value of the sodium alginate‐silicone emulsion‐coated paper was 41.6 g/m2, much higher than that of the uncoated paper, with a Kit grade of up to Level 10, which could slow down the rate of castor oil penetration at 80°C within 24 h. The test results showed that there was no chemical reaction between the paper‐based coatings, and the coated paper surface had good film formation, while the double coating method increased the thermal decomposition temperature of the overall barrier coating, effectively improving the thermal stability of the coating and achieving high‐barrier performance at lower cost and under extreme working conditions. Highlights: Water and oil resistance under extreme operating conditions.High‐performance paper‐based barrier materials.Dual‐layer coating method for water and oil repellency.High‐barrier performance at lower cost.Excellent hot oil resistance and thermal stability. [ABSTRACT FROM AUTHOR]

With the implementation of plastic restrictions and the increasingly serious problem of environmental pollution, paper with green and recyclable characteristics is gradually becoming a substitute for packaging materials. However, the rich cellulose structure in the paper, which contains hydroxyl groups leading to its hydrophilicity, allows water molecules to penetrate the paper and disrupt the hydrogen bonds between cellulose, resulting in a decrease in mechanical properties. Therefore, waterproof coatings are crucial for paper‐based materials to be used in many applications. Based on this, the paper surface was chemically modified with castor oil‐based resin (CO‐590) monomer prepared by coupling agent and castor oil (CO). The results indicated that the modified paper with the contact angle (CA) of 114° had excellent waterproof performance and had a reduction by 40.3% in water vapor transmission rate (WVTR), but also its mechanical increased to 26.9 MPa and the decomposition temperature to 410.5°C. In addition, the coating on its surface could be removed in an alkaline solution and had a possibility to recycle blank paper in the future for manufacturing sustainable production. This work not only provides a method for preparing modified packaging paper, but also expands the application fields of materials. [ABSTRACT FROM AUTHOR]

Background: Pigment Red 53 is a dangerous synthetic dye that is often added to cosmetics, even though its use in cosmetic products has been prohibited because of possible impacts on health. Faster and more sensitive detection of Pigment Red 53 is needed for onsite analysis to protect the community from illegal cosmetics that contain the dye. Indicator color charts are a kind of analytical method that can be used to detect Pigment Red 53 in cosmetic products, including lipstick, rouge, and eyeshadow. Such charts are practical, fast, and can be used for onsite analysis. Methods: In this study, an indicator for Pigment Red 53 detection was obtained through a reagent reaction that caused a specific color change. An indicator color chart was then produced by setting out in paper form the series of colors which resulted from the reaction of specific chemical reagents and Pigment Red 53 solutions at concentrations of 10, 20, 40, 60, 80, and 100 ppm. Results: The testing results showed that the indicator color chart may be used as an initial screening method for the detection of Pigment Red 53 in cosmetic products with a detectable minimum concentration of 10 ppm. Out of nine samples, only one (Eyeshadow 3) tested positive for Pigment Red 53. Further analysis was carried out on the indicator color chart and the results showed good agreement with TLC and UV–Vis spectrophotometry methods. Conclusion: The results reported in this paper demonstrate that the indicator color chart is a good prospective method for onsite analysis to detect Pigment Red 53 in cosmetic samples, with a lower detection limit compared to polymer‐based indicators. [ABSTRACT FROM AUTHOR]

Kenichi Fukui shared the 1981 Nobel Prize in Chemistry with Roald Hoffmann for "their theories, developed independently, concerning the course of chemical reactions." This is Paper 4 – Part I, of a three‐part trilogy within a 27‐paper series on the history of the development of the Woodward‐Hoffmann rules. The personality and professional style of Fukui is discussed as well as his style of teaching and his mottos and sayings. A brief chronological history of his academic and professional life is presented along with a listing of Fukui's great flexibility in behaviors and in science. Lastly, a short list of Fukui's key awards is provided. [ABSTRACT FROM AUTHOR]

Reactive distillation (RD) is a process intensification technique that offers major advantages over conventional technologies by enabling the integration of reaction and separation into a single apparatus. This integration introduces and exploits complex interaction between mass transfer, chemical reaction and hydrodynamics within an RD column; however, these complexities can hinder the adoption of RD by industry. Many approaches have been developed by the scientific community to advance understanding and to expedite the initialization of RD design at the conceptual level. This paper critically discusses recent developments in conceptual methods for synthesizing RD processes. This review paper is the first to consider the range of available approaches for assessing the technical feasibility, controllability, economic viability, and sustainability of RD units by taking into account various configurations in which RD is treated as a new unit operation, and as part of process synthesis in a different way of designing processes based on functions. The review also addresses complex configurations, such as advanced RD technologies. Special attention is paid to process modeling and simulation as well as to education. Knowledge gaps to be filled by further research are indicated. © 2024 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

An exciting new class of heat transmission fluids, nanofluids, has been developed as an alternative to traditional fluids in manufacturing. Fuel cells, heat exchangers and pharmaceutical processes are just a few of the many uses for them. When compared to monofluids, the heat transmission properties of hybrid fluids are superior. These are findings used in an extensive diversity of fields, from solar energy to air conditioning. The objective of this paper is to examine how Lorentz force and chemical reaction parameters affect the characteristics of a couple stress hybrid nanofluid (Ethylene Glycol + Graphene + Copper) flow via an exponentially stretching surface. The heat transport phenomenon is studied using viscous dissipation, exponential heat source and thermal radiation parameters. Furthermore, irreversibility analysis is provided in this paper. Governing equations are transformed into a set of nonlinear ordinary differential equations using suitable similarity transformations. The bvp4c solver in MATLAB is used to solve the transformed system. Engineering parameters of interest, including skin friction coefficient, are described using bar diagrams. It has been noted that the magnetic field and volume fraction of graphene nanoparticles (ϕ1) reduce the skin friction coefficient. At 0≤ϕ1≤0.105$0 \le {\phi }_1 \le 0.105$, the skin friction coefficient decreases at a rate of 4.68187. It is observed that there is an increment in the fluid temperature with the rise in the exponential heat source parameter, and the velocity profile increases with the increase in the mixed convection parameter. It is detected that, while Eckert number (Eck$Eck$) was set to 0≤Eck≤0.7$0 \le Eck \le 0.7$, Nusselt number was reduced by 6.29239. It is noticed that, while the chemical reaction (Cr$Cr$) is set to 0≤Cr≤0.7$0 \le Cr \le 0.7$, the mass transfer rate rises at a Rate of 0.349644. It has been observed that as the Brinkmann number and magnetic field parameters increase, so does the rate of entropy production. It is also detected that as the porosity parameter increases, the fluid momentum decreases. Furthermore, increasing the couple stress parameter decreases the fluid velocity. [ABSTRACT FROM AUTHOR]

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

Cookoff experiments of powdered and pressed TATB‐based plastic bonded explosives (PBXs) have been modeled using a pressure‐dependent universal cookoff model (UCM) in combination with a micromechanics pressurization (MMP) model described in a companion paper. The MMP model is based on the accumulation of decomposition gases at nucleation sites that load the surrounding TATB crystals and binder. This is the first cookoff model to use an analytical mechanics solution for compressibility and thermal expansion to describe internal pressurization caused by both temperature and decomposition occurring within closed‐pore explosives. This approach produces more accurate predictions of ignition time and pressurization within high‐density explosives than simple equation‐of‐state models. The current paper gives details of the reaction chemistry, model parameters, predicted uncertainty, and validation using experiments from multiple laboratories with errors less than 6 %. The UCM/MMP model framework gives more accurate thermal ignition predictions for high density explosives that are initially impermeable to decomposition gases. [ABSTRACT FROM AUTHOR]

In this paper, we review the concept of synergistically using ultrasonic sonochemistry in combination with heterogeneous catalysis, to selectively perform condensed phase chemical transformations. Through specific examples, we highlight that ultrasound induced cavitation bubbles not only provide local high temperature and pressure conditions for initiating chemical reactions but also improves heat, mass and charge transfer characteristics in the system. We also show that sonocatalysis can alter reaction mechanisms and open new activation and reaction pathways that are not intuitive to thermocatalysis. Computational chemistry tools are introduced and are combined with sonocatalysis experimental studies to demonstrate that, in‐situ generated radicals propelled into the bulk liquid solution upon bubbles implosion can be stabilized by catalyst surfaces, while creating active sites for unique reactions during heterogeneous sonocatalytic chemistry. We also report recent examples of condensed phase sonocatalysis applications, including pollutant degradation, chemical and pharmaceutical synthesis and biomass upgrading, and provide mechanistic insights into the process. [ABSTRACT FROM AUTHOR]

Ionic liquids (IL) have emerged as the potential class of solvents for various chemical processes and reactions, including gelatinization and chemical modification of starch. Through various studies it has been established that expensive nature of ILs can be counter balanced by employing the mixture of IL/water instead of pure ILs. The IL/water system has the advantage to plasticize starch more effectively due to their synchronal effect and rational viscosity. The properties of ILs can be tempered by preferring particular cations/anions according to the specific type of starch which may be helpful in convenient dissolution and modification of starch. Starch can be modified by esterification or etherification reaction in IL medium to alter their properties and to use it in various application areas. Starch dissolution is subjected to various parameters like type of starch, nature of IL, ratio of IL/water, and temperature which has been discussed elaborately in the present review paper. [ABSTRACT FROM AUTHOR]

Piezocatalysis is attracting extensive attention in recent years because it can directly convert mechanical energy from the ambient environment (such as tiny vibrations and noise) into piezopotential for catalytic activities. Dyes are widely used in diverse industries, including paper, printing, and textiles, which cause serious environmental problems due to their persistence and toxicity. Unlike traditional catalysts that rely on chemical reactions to drive dye degradation, piezocatalysts offer a sustainable and cost‐effective alternative to breaking down complex molecules through creating highly reactive species, which have shown a significant promise in the treatment of organic pollutants in wastewater. In this review, the basic principles of piezocatalysis are first outlined, specifically describing two ubiquitous forms of driving force in nature. Following the catalytic mechanism, the current mainstream piezocatalytic materials are classified into two categories: organic and inorganic materials with detailed discussions. Moreover, after investigating and analyzing previous literature, effective strategies for improving piezocatalytic efficiency for dye degradation are systematically compared and summarized. In the end, current issues that need to be addressed in the future as well as potential research directions related to piezocatalysis are prospected. This work provides an insight into solving current issues to advance the piezocatalysts. [ABSTRACT FROM AUTHOR]

Chiral phosphoric acid (CPA) has been established as a cornerstone in chemical synthesis reactions for over five decades, owing to its distinctive molecular structure and remarkable catalytic effect. However, in recent years, a revolutionary approach to asymmetric synthesis has emerged, utilizing photocatalytic excitation of molecules to generate free radicals, effectively surpassing the limitations of classical organic synthesis methodologies.A prominent and significant area of research has been dedicated to the investigation of chiral phosphoric acid synergistic photocatalysis for enantioselective chemical synthesis. This unique catalytic system encompasses a bifunctional hydrogen‐bonding catalyst, enabling simultaneous interactions between radical intermediates and substrates. The review paper focuses on the application and progress of this catalytic system in asymmetric synthesis throughout the past decade. [ABSTRACT FROM AUTHOR]

Sandwich panels consist of two thin‐walled steel faces plus an insulation core. For this core, materials are selected that provide high (shear) stiffness and high thermal resistance. When the panels are subject to fire, the (a) temperature‐dependent behaviour of the steel faces and (b) the possible chemical reactions of the insulation core should both be considered, to accurately predict the structural behaviour. Provisions in Eurocode EN 1993‐1‐2 can be used for (a). Regarding (b), this paper adds a verified pyrolysis model to Heat Transfer (HT) analyses, and obtained results are transferred to a Structural Response (SR) analysis. Then, the HT and SR analyses are demonstrated in so‐called One‐Way Coupled (OWC) and Two‐Way Coupled (TWC) fire‐structure simulations, the latter including the effects of structural failure on the fire behaviour. For the cases studied, structural behaviour for OWC and TWC simulations is very similar, which indicates that the structural (failure) behaviour does not significantly influence the fire behaviour. Differently, the difference in failure time between simulations with and without pyrolysis is more than 15%, due to endothermic effects. As such, for the cases studied, modelling of pyrolysis is more important than the effect of structural failures, and this modelling can be included as demonstrated in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the effects of Hall current, radiation absorption and diffusion thermo on unsteady magnetohydromagnetic free convection flow of a viscous incompressible electrically conducting and chemically reacting second‐grade fluid past an inclined porous plates in the presence of an aligned magnetic field, thermal radiation, and chemical reaction. An exact analytical solution of the governing equations for fluid velocity, fluid temperature, and species concentration subject to appropriate initial and boundary conditions is obtained using the perturbation technique. Expressions for shear stress, rate of heat transfer, and rate of mass transfer at the plate are derived. The numerical values of primary and secondary fluid velocities, fluid temperature and species concentration are displayed graphically, whereas those of shear stress and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. In addition, the skin friction on the boundary, the heat flux expressed in terms of the Nusselt number, and the rate of mass transfer described in the Sherwood number are all derived, and their behavior is studied computationally. It can be deduced that an increase in radiation absorption and hall current parameters over the fluid region increases the velocity produced. The resulting velocity continually increases to a very high level, with contributions coming from thermal and solutal buoyancy forces. Skin friction may decrease by manipulating the rotation parameter, but the Hall effect can worsen it. When the parameter for the chemical reaction increases, there is a concomitant rise in the mass transfer rate. [ABSTRACT FROM AUTHOR]

Internet of things (IoT) devices are equipped with a number of interconnected sensor nodes that relies on ubiquitous connectivity between sensor devices to optimize information automation processes. Because of the extensive deployments in adverse areas and unsupervised nature of wireless sensor networks (WSNs), energy efficiency is a significant aim in these networks. Network survival time can be extended by optimizing its energy consumption. It has been a complex struggle for researchers to develop energy‐efficient routing protocols in the field of WSNs. Energy consumption, path reliability and Quality of Service (QoS) in WSNs became important factors to be focused on enforcing an efficient routing strategy. A hybrid optimization technique presented in this paper is a combination of fuzzy c‐means and Grey Wolf optimization (GWO) techniques for clustering. The proposed scheme was evaluated on different parameters such as total energy consumed, packet delivery ratio, packet drop rate, throughput, delay, remaining energy and total network lifetime. According to the results of the simulation, the proposed scheme improves energy efficiency and throughput by about 30% and packet delivery ratio and latency by about 10%, compared with existing protocols such as Chemical Reaction Approach based Cluster Formation (CHRA), Hybrid Optimal Based Cluster Formation (HOBCF), GWO‐based clustering (GWO‐C) and Cat Swarm Optimization based Energy‐Efficient Reliable sectoring Scheme with prediction algorithms (P_CSO_EERSS). The study concludes that the protocol suitable for creating IoT monitoring system network lifetime is an important criteria. [ABSTRACT FROM AUTHOR]

The epoxidation of propylene with dilute H2O2 aqueous solution over titanium silicalite‐1 (TS‐1) zeolite catalyst is a green chemical reaction for propylene oxide (PO) production. Carrying out the reaction in gas‐phase can get rid of problems caused by using methanol solvent. This paper reports an attempt of using non‐zeolite catalyst for the gas‐phase epoxidation. Amorphous Ti/SiO2, obtained by grafting amorphous SiO2 with TCl4 in ethanol solvent in a chemical liquid‐phase deposition (CLD) process, has been used as the catalyst. Results show that the CLD Ti/SiO2 with appropriate Si/Ti molar ratio is an active catalyst for gas‐phase epoxidation, achieving 9.8 % propylene conversion and 66.9 % PO selectivity with 40.3 % H2O2 utilization, which indicates that this amorphous Ti/SiO2 catalyst deserves extensive studies in the future. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of Hall current, chemical reaction, and radiation on transient magnetohydrodynamics flow past an inclined plate. The basic nonlinear partial differential equations (PDEs) are converted to dimensionless nonlinear PDEs with similar transformations. The transformed flow equations are solved by the finite element method with appropriate initial conditions. The influence of physical parameters on velocities, temperature, as well as concentration dispensations is addressed computationally and demonstrated by graphs. The influence of flow parameters on skin‐friction coefficients τ1 and τ2 are discussed and presented in the form of a table. Finally, a qualitative similarity was made between the present paper and the earlier published results and it was initiated that there is tremendous conformity between the results. [ABSTRACT FROM AUTHOR]

Hydroxyl‐terminated polybutadiene (HTPB) is hydrogenated using catalytic hydrogenation with HTPB as a precursor using various catalysts. The hydrogenation is carried out using iso‐propyl alcohol (IPA) and toluene as an active solvent media. The present paper used (a) charcoal, (b) palladium supported by charcoal (Pd−C), (c) palladium supported by zirconium oxide (Pd‐ZrO2), and (d) copper chromite (CC) as catalysts for hydrogenation of HTPB to study the influence on the degree of hydrogenation with respect to each catalyst. The experimental data shows that hydrogenated HTPB (HHTPB) formation is predominantly controlled by physisorption and chemical reaction with a catalyst. Various techniques like NMR, FTIR and chemical analysis are used to characterize HTPB and HHTPB. Degree of hydrogenation of HTPB is found to be higher with copper chromite when compared to other catalysts in this work. Post‐hydrogenation, no significant change in hydroxyl value and a marginal increase in molecular weight is noticed with all catalysts. HTPB and HHTPB samples are analyzed using FTIR, 1H‐NMR, and 13C‐NMR and TG‐DSC studies, and inferences are derived with respect to the change in the olefinic region, microstructural changes, molecular weight, and thermal decomposition characteristics. [ABSTRACT FROM AUTHOR]

Free radicals are increasingly recognized as active intermediate reactive species that can participate in various redox processes, significantly influencing the mechanistic pathways of reactions. Numerous researchers have investigated the generation of one or more distinct photogenerated radicals, proposing various hypotheses to explain the reaction mechanisms. Notably, recent research has demonstrated the emergence of photogenerated radicals in innovative processes, including organic chemical reactions and the photocatalytic dissolution of precious metals. To harness the potential of these free radicals more effectively, it is imperative to consolidate and analyze the processes and action modes of these photogenerated radicals. This conceptual paper delves into the latest advancements in understanding the mechanics of photogenerated radicals. [ABSTRACT FROM AUTHOR]

In the present paper several aspects of the simulation of complex chemical equilibrium are discussed, using two research and educational software: gPROMS® and GAMS®. All computations are performed to boost the understanding of chemical engineering students, undergraduate, and graduate, of the complex concepts behind both thermo‐chemical processes and optimization techniques. Four case studies with varying levels of difficulty illustrate the proposed methodology and robustness of the modeling systems: 1.Catalytic steam reforming of bio‐ethanol at high temperatures.2.Partial oxidation of naphthalene using either air or pure oxygen.3.Supercritical water gasification of Microalga Spirulina.4.Dry and mixed reforming of glucose. Our results indicate that the use of optimization tools offered bygPROMS® and GAMS®software are useful and efficient tools to calculate the chemical and phase equilibrium by minimizing the Gibbs energy, provided that adequate initial guesses are used. Furthermore, the computational time spent in the calculations was generally quite short. The obtained equilibrium compositions are benchmarked using the ubiquitous process simulators: ASPEN‐Plus® and/or ASPEN‐Hysys® as well as data available from the open literature. We obtained excellent agreement between our results and their counterpart obtained using ASPEN‐Plus®. In the last part of this manuscript, authors share their experience in supervising senior term projects on the subject. A questionnaire was used to collect qualitative and quantitative feedback from the nine students involved in the projects. Their responses to a questionnaire focused on the chemical engineering thermodynamics theory as well as software usage during their investigations. This questionnaire demonstrates that students can overcome mathematical complexity by either using mathematical software or equivalent modeling systems (e.g., Matlab®, Mathematica©, gPROMS®, and GAMS®). [ABSTRACT FROM AUTHOR]

In this paper, In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) films with a single spinel phase are successfully grown at the low temperature of 300 °C through careful cation composition design and a catalytic chemical reaction. Thin‐film transistors (TFTs) with amorphous In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) channel layers have a reasonable mobility of 41.0 cm2 V−1 s−1 due to the synergic intercalation of In and Sn ions. In contrast, TFTs with polycrystalline spinel In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) channel layers, achieved through a metal‐induced crystallization at 300 °C, exhibit a remarkably high field‐effect mobility of ≈83.2 cm2 V−1 s−1 and excellent stability against external gate bias stress, which is attributed to the uniform formation of the highly ordered spinel phase. The relationships between cation composition, microstructure, and performance for the In2O3–ZnO–SnO2 ternary component system are investigated rigorously to attain in‐depth understanding of the roles of various crystalline phases, including spinel Zn2−ySn1−yIn2yO4 (y = 0.45), bixbyite In2−2xZnxInxO4 (x = 0.4), rutile SnO2, and a homologous compound of compound (ZnO)k(In2O3) (k = 5). This work concludes that the cubic spinel phase of Zn2−ySn1−yIn2yO4 (y = 0.45) film is a strong contender as a substitute for semiconducting polysilicon as a backplane channel ingredient for mobile active‐matrix organic light‐emitting diode displays. [ABSTRACT FROM AUTHOR]

The evolving factor analysis (EFA) facilitates the detection of the emergence or loss of chemical species during a chemical reaction, a chromatographic process, a spectroelectrochemical analysis, and other experiments. To this end, EFA monitors the singular values of sequences of spectral data matrices with increasing dimensions. This paper studies the growth behavior of these singular values. It investigates properties of the EFA techniques, analyzes the general shape of the singular value curves, and gives practical remarks for an improved extraction of chemical information from EFA plots. The evolving factor analysis (EFA) monitors the singular values of sequences of spectral data matrices with increasing dimensions. This paper analyzes the growth behavior of these singular values. It investigates properties of EFA plots, analyzes the shape of the singular value curves, and gives practical remarks for an improved extraction of chemical information from EFA plots. [ABSTRACT FROM AUTHOR]

Wettability is an important property of solid surfaces, superwetting materials can be prepared by controlling the surface morphology and surface energy. In recent years, superwetting materials have been researched and used widely in the fields of self‐cleaning, anti‐fogging, microfluidics, and oil–water separation, but few studies about superwetting materials in chemical reactions have been conducted. In the multiphase reaction, the low solubility and diffusion rate of gas lead to inferior mass transfer, which restricts the reaction kinetics and reduces the reaction rate. Therefore, it may be a breakthrough to make the solid surface obtain underwater superaerophilicity. In this paper, 1H,1H,2H,2H‐perfluorooctyltriethoxysilane (POTS) with low surface energy was constructed on the palladium‐carbon nanotubes (Pd‐CNTs), as‐prepared Pd‐CNTs/POTS composite has excellent hydrophobicity and underwater superaerophilicity. When Pd‐CNTs/POTS composite was utilized in the catalytic hydrogenation, Pd‐CNTs/POTS composite shows higher catalytic activity than Pd‐CNTs; the higher catalytic performance is attributed to the underwater superaerophilicity, which enables gaseous hydrogen to rapidly accumulate on the surface of material, increasing the gas–liquid–solid reaction interface formed. The strategy looks forward to providing a new way for developing novel and efficient heterogeneous catalysts and reaction systems. [ABSTRACT FROM AUTHOR]

This paper investigates the heat and mass transfer of an unsteady, magnetohydrodynamic incompressible water‐based nanofluid (Cu and TiO2) flow over a stretching sheet in a transverse magnetic field with thermal radiation Soret effects in the presence of heat source and chemical reaction. The governing differential equations are transformed into a set of nonlinear ordinary differential equations and solved using a regular perturbation technique with appropriate boundary conditions for various physical parameters. The effects of different physical parameters on the dimensionless velocity, temperature, and concentration profiles are depicted graphically and analyzed in detail. Finally, numerical values of the physical quantities, such as the local skin‐friction coefficient, the Nusselt number, and the Sherwood number, are presented in tabular form. It is concluded that the resultant velocity reduces with increasing Jeffrey parameter and magnetic field parameter. Results describe that the velocity and temperature diminish with enhancing the thermal radiation. Both velocity and concentration are enhanced with increases of the Soret parameter. Also, it is noticed that the solutal boundary layer thickness decreases with an increase in chemical reaction parameters. This is because chemical molecular diffusivity reduces for higher values of chemical reaction parameter. Also, water‐based TiO2 nanofluids possess higher velocity than water‐based Cu nanofluids. Comparisons with previously published work performed and the results are found to be in excellent agreement. This fluid flow model has several industrial applications in the field of chemical, polymer, medical science, and so forth. [ABSTRACT FROM AUTHOR]

Metal catalyzed polymerizations are among the most important chemical reactions, accounting for the production of about 400 million tons per year of polymeric materials, 50 % of which are polyolefins. The CIRCC research units at the University of Salerno, founded by the late Professor Adolfo Zambelli, a coworker of Giulio Natta and a pioneer in the studies of stereospecific polymerization catalysts, has a consolidated expertise in this field. Although often considered a "mature" area of research, olefin polymerization catalysis continues to drive great interest of both industrial and academic scientists. On the other hand, strong political and economic pressure toward the development of "green" and possibly biodegradable alternatives to olefin‐based polymers stimulated our group to direct increasing research efforts in the area of sustainable polymers. In this perspective, we focus on the most recent work from the CIRCC research units involved in homogeneous catalysis for polymerization of a variety of monomers, with the aim to address how the concepts and the expertise developed for olefin polymerization can be applied to the development of different metal‐catalyzed polymerizations and copolymerizations. Of course, although the results are discussed in the frame of the most important literature contributions, a comprehensive review of such a wide and diversified topic is out of the scope of the paper. References to reviews covering the different types of metal catalyzed polymerizations are provided in each chapter. [ABSTRACT FROM AUTHOR]

Poly(ionic liquid) (PIL)‐based porous membranes are extensively investigated as soft polymer actuators. While PILs have shown significant advancements in membrane fabrication and stabilization of metal nanoparticles (MNPs), research on integrating MNPs into porous membranes to achieve actuation behavior under multiple stimuli is limited. Herein, this work presents a new paradigm for designing a porous PIL‐polyacrylic acid (PAA) membrane with a distinct MNP gradient via a top‐bottom diffusion approach involving a metal salt precursor solution and NaBH4 as a reducing agent. The strong binding sites provided by PILs, combined with the gradient distribution of ‐COO− groups across the membrane cross‐section, play a significant role in controlling the MNPs' gradient distribution. Interestingly, the MNPs within the membrane display excellent catalytic activity in exothermic reactions such as H2O2 decomposition, dissipating uneven heat that quickly permeates the membrane network. This induces asymmetrical swelling of polymer chains, resulting in rapid membrane bending. Furthermore, such MNP‐loaded membrane could serve as a portable test paper for visually monitoring H2O2. This advancement paves the way for the development of intricate smart actuation materials and expands their practical applications in various real‐life scenarios. [ABSTRACT FROM AUTHOR]

Photocatalysis utilizes light as the initial driving force for chemical reactions, enabling reactions with high energy barriers in traditionally thermal chemistry to proceed under mild conditions. 1,3‐Dicarbonyl compounds occur as important active molecules in nature and are intermediates in pharmaceutical syntheses. In recent years, there have been numerous studies of these compounds, and it is common practice to pre‐modify them before the reaction, which is, however, unfavorable for the atom economy of the process. This paper provides a comprehensive review of the latest advancements in the site‐specific activation of unmodified 1,3‐dicarbonyl compounds by photoinduction. The focus is on elucidating the mechanisms of these reactions to provide insights and directions for future research in designing novel reactions. [ABSTRACT FROM AUTHOR]

Monitoring the ratio of two normal random variables, which is usually denoted as RZ, is one of the most important directions in statistical process control (SPC). In production scenarios, when the product specification is related to the relative ratio of two components in a mixture, or when the ratio represents a property of the product, or the difference between a product's quality measurement before and after an operation (such as a chemical reaction), the product quality can be improved by applying monitoring schemes for RZ. To further enhance the sensitivity of traditional RZ schemes in detecting process changes, especially small and moderate ones, this paper proposes an improved exponentially weighted moving average (IEWMA) monitoring scheme. The run length (RL) distribution of the proposed IEWMA‐RZ scheme is obtained by using the Monte‐Carlo (MC) simulation. The superiority of the proposed monitoring scheme is shown by comparing with the existing EWMA‐RZ scheme. [ABSTRACT FROM AUTHOR]

Benzophenone and related derivatives are widely used as photoinitiators for food packaging to cure inks or lacquers with ultraviolet (UV) light on cardboard and paper. However, there are concerns about the potential health risks of their migration into food. Knowing the physical and chemical properties of benzophenone and its derivatives could play a significant role in their quantification and analysis using chemical ionization mass spectrometry (CI‐MS) methods. These parameters are evaluated using B3LYP/6‐311++** density functional theory (DFT) implemented on Gaussian code. Ion–molecule chemistry through the selection of reagent ions, reaction energetics and kinetics, thermodynamic stability, and reactivity of molecules deemed to foster VOC identification and quantification via CI‐MS techniques. The VOCs under study are expected to undergo exothermic reactions from H3O+, NH4+, NO+, and O2+ ions, except endothermic proton transfer from NH4+ to 2‐hydroxy‐4‐methoxybenzophenone and 2,3,4‐trihydroxy benzophenone. These compounds possess less proton affinities than NH3 and are least stable in their protonated forms. The DFT computed properties provide the basis for developing reliable and accurate methods to detect and measure the presence of benzophenone and its derivatives in packaging materials and food products. [ABSTRACT FROM AUTHOR]

Due to extensive application in extruding plastic sheet processes, liquid film condensation, glass blowing, biopolymer cylinder coatings, paper manufacture, and other processes, the thermodynamical characteristics of non‐Newtonian fluids across stretched surfaces have acquired ubiquitous essence. Therefore, the present communication aims to openly elucidate Prandtl fluid flow characteristics produced by a stretching surface. In this analysis, a hybrid nanofluid (HNF) is considered by using pure water as a base fluid and two various nanomaterials (copper and Titanium dioxide) as nanoparticles in the characterization of heat transfer. Moreover, the goal of this investigation is to ascertain the heat transfer characteristics of a magnetohydrodynamic (MHD) Prandtl hybrid nanofluid (PHNF) model. Across the stretching sheet, this article interrogates the inclined MHD, chemical reaction, bio‐convection, linearly thermal radiation, and Darcy–Forchheimer (DF) effect in the attendance of porous medium of HNF. The modified Buongiorno model for nanofluids is adopted to explore heat transport augmentation. It includes the mechanics of nanoparticle random motion and thermo‐migration as well as useful nanofluid characteristics. Additionally, the outcomes are contrasted with nanofluid flow. With the right level of similarity, the process converts partial differential equations emerging in nanofluidic systems into nonlinear differential equation systems. The (FDM) finite difference approach (Lobatto IIIA) is used for the nonlinear nanofluid issue with the precision of order 4 to 5 and is implemented using a variety of collocation locations. The strength of (Lobatto IIIA) is its effectiveness in handling coupled differential equations that are extremely nonlinear. The higher‐order differential equations are converted into a first‐order method utilizing the boundary value dilemma (bvp4c) solver, which is part of the MATLAB software package, to computationally analyze the simplified mathematical model. The data obtained demonstrated a high degree of accuracy and symmetry when measured against previously published studies. Following earlier studies, increasing the values of the Prandtl parameters increases the velocity profiles of both basic nanofluid and HNF, while the Forchheimer and porosity parameters reduce fluid velocity. Additionally, as the values of the magnetic parameters increase, the temperature and concentration of simple and HNFs rise as well. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) as relatively stable reactive oxygen species gains considerable attention because it can regulate physiological and pathological processes. In order to better detect H2O2, fluorescent probes were widely applied. Over the past 20 years, a great deal of boronate‐based fluorescent molecular probes appeared due to relatively simple oxidation reaction. However, the reaction mechanisms that boronate derivatives were converted into fluorescent product by H2O2 are poorly studied. In this paper, taking coumarin‐7‐pinacolboronate (CBU) as an example, the oxidation mechanism of boronate‐based probes by various reactive oxygen species was studied by theoretical calculations. The results found that (1) the chemical reaction mechanisms are nearly identical for the reactions of CBU with hydrogen peroxide, hypochlorous acid, peroxynitrite, and tyrosine hydroperoxide, respectively. (2) There is not radical intermediate during the reaction. (3) The different reactive oxygen species has a strong influence on rate limiting step and reaction rate. [ABSTRACT FROM AUTHOR]

This paper aims to present a comprehensive study of the non‐linear peristaltic transport within a vertical uniform/non‐uniform channel filled with a Jeffery non‐Newtonian nanofluids in the presence of oxytactic microorganisms. The thermal conductivity of the used physiological fluids is varied linearly with the temperature while Arrhenius function is applied for the activation energy. The significance of electrical and magnetic fields together with a linear radiation and viscous dissipation are analyzed. The flow and heat transfer analysis has been performed under wall slip and compliant conditions. Additionally, optimization of the system entropy under the impacts of these aspects is examined. Numerical solutions for the governing system are introduced and profiles of the velocity u, temperature θ, nanoparticle distributions φ, heat transfer coefficient z and extra stress tensor distribution Sxy${S_{xy}}$ for the variations of the considered parameters are discussed. The main outcomes revealed that the maximizing of the Brinkman number Br$Br$ is better to get higher features of the extra stress tensor Sxy${S_{xy}}$. Also, the velocity u, density of the microorganisms ξ and the NP distributions in the interval −0.5

A simple approach to mitigate the use of high voltages on thin bipolar electrodes is described here for the first time. The method involves stacking the desired thin conductor onto a thicker one, thereby creating a pseudo‐single electrode whose width is the sum of the two. Placing the target material on the positive or negative face of the combined bipolar electrode selects which reaction it will be involved in. This method is used to graft sheets of carbon paper, cloth, and buckypaper with an aminophenyl layer that subsequently binds polypyrrole in a simple two stage reaction to create a one‐sided deposit of a supercapacitive material. By itself the necessary driving potential for these reactions exceed 90 V, while with the stack it drops to 9 V. The resulting supercapacitor electrodes display good performance, with specific capacitances up to 210 mF/cm2 and lasting 2500 charge/discharge cycles. [ABSTRACT FROM AUTHOR]

In this paper, we have explored the hydromagnetic free convective flow over an unlimited perpendicular porous plate in the presence of temperature resources. The prevailing equations are subsequently solved systematically by utilizing the perturbation methodology. The velocity, temperature as well as concentration sketches are shown in graphical profiles. The impacts in the flow area for dissimilar leading parameters have been explored. Also, the skin frictions, the Nusselt quantity along with the Sherwood quantity are computed with different parameters and mentioned in the tables. The velocity diminishes with an escalation in the chemically reacting parameter as well as improves with an increment in the temperature resource parameter. The temperature field reduces with an augment in the Prandtl number. The concentration field is enhanced by amplifying in the chemically reacting variable, whereas it lessens with amplifying in the Schmidt number. [ABSTRACT FROM AUTHOR]

The present paper studies the effect of a chemical reaction and aligned magnetic field on an unsteady magnetohydrodynamic free convection Kuvshinski fluid flow past an inclined plate through a porous medium in the presence of Soret and radiation. The plate is assumed to be embedded in a uniform porous medium and moves with a constant velocity in the flow direction in the presence of a transverse magnetic field. The systems of nondimensional governing linear partial differential equations are solved analytically by using the perturbation technique. The influences of various nondimensional parameters on the velocity, the temperature, and the concentration are discussed, as also the effects of various parameters on the skin‐friction coefficient and the rate of heat transfer in the form of Nusselt number and rate of mass transfer in the form of Sherwood number at the surface. Velocity distribution is observed to increase with an increase in viscoelastic parameter and Soret parameter, whereas it shows reverse effects in the case of the aligned magnetic field, inclined parameter, magnetic parameter, the temperature diminishes with the increase of radiation parameter and heat absorption parameter. [ABSTRACT FROM AUTHOR]

In this paper we investigate the mixed convection flow of a Williamson fluid under the effects of temperature dependent thermal conductivity and chemical reaction. The mathematical model for this phenomenon is described in a set of partial differential equations (PDEs) and further this set is reduced to a dimensionless system of nonlinear partial differential equations (PDEs) using a non‐similarity method. The non‐similarity method has an advantage over similarity methods for handling non‐similar problems. The method first uses transformations to reduce governing equations into dimensionless systems of PDEs. The effects of Grashof number of heat and mass transfer Weissenberg number, Prandtl number, Schmidt number and reaction rate parameters on velocity, temperature, and concentration profiles are given in forms of graphs. [ABSTRACT FROM AUTHOR]

Improving the stability of sensitive catalytic systems is an emerging research topic in the catalysis field. However, the current design of heterogeneous catalysts mainly improves their catalytic performance. This paper presents a single‐atom catalyst (SAC) strategy to improve the cobalt‐catalysed fluorination of acyl chlorides. A stable Co−F intermediate can be formed through the oxidative fluorination of Co1−N4@NC SAC, which can replace the unstable high‐valent cobalt catalytic system and avoid the use of phosphine ligands. In the SAC system, KF can be employed as a fluorinating reagent to replace the AgF, which can be applied to various substrates and scale‐up conversion with high turnover numbers (TON=1.58×106). This work also shows that inorganic SACs have tremendous potential for organofluorine chemistry, and it provides a good reference for follow‐up studies on the structure‐activity relationship between catalyst design and chemical reaction mechanisms. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) exhibit vivid photoluminescence in solutions, but show no or weak photoluminescent emissions in solid state. In this paper, we prepared a polyurethane (PU)/CD composite with solid‐state fluorescence under ultraviolet (UV) irradiation by anchoring oil‐soluble CDs in a crosslinked PU matrix through chemical reaction. This polymer composite has high robustness, transmittance, and organic solvent resistance, as well as good stretching ability. Interestingly, since the chemical reaction between the CDs and the PU matrix changes the UV absorption feature of the CDs, the PU/CD composite has blue (near 405 nm), cyan (near 470 nm), and green (near 495 nm) fluorescent emissions, even though the CD solution just possesses green (near 530 nm) fluorescent emissions. This PU/CD composite shows the possibility of application in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Chemical equilibrium calculations—as they are required to evaluate the evolution limits of any reactive system—are fundamentally performed using either a reaction based stoichiometric (S) approach or a non‐stoichiometric (NS) method. One objective of the present paper is to check and discuss whether both methods lead to comparable solutions in the case of complex chemical equilibria encountered in high temperature and pressure combustion of hydrazine and propane and in steam gasification of glucose and cellulose. Within both calculation models various numerical methods can be used. We apply several techniques for each approach and discuss their easiness of implementation and usage, in particular when chemical equilibria are computed for reacting systems under a multitude of temperature and pressure conditions and feed compositions. In addition, we present a novel approach to perform sensitivity analyses based on a combination of S or NS methods and arc‐length continuation technique. For this purpose, three industrially relevant case studies are exposed: (1) synthesis of ammonia using the Haber process, (2) steam gasification of a typical biomass surrogate, glucose, and (3) steam gasification of cellulose. For all the above reacting systems, our results are benchmarked against their counterparts obtained either from the ubiquitous process simulator: ASPEN‐Plus® or from data available in the open literature. [ABSTRACT FROM AUTHOR]

Research on so‐called "chemical artificial intelligence" (CAI) is an emerging field with the aim of constructing information‐processing systems with learning capabilities based on chemical methodologies. This can be regarded as an attempt to reconstruct Cybernetics using molecular based systems. Many chemical reaction systems with computational abilities are proposed, but most are fixed functions that deliver molecular output for a given molecular input. On the other hand, chemical AI is a system with learning capability; namely, the output should be variable and gradually change upon repeated molecular inputs. In this paper, a compartmentalization approach for implementing cellular chemical AI using liposomes is discussed. The existing studies in terms of the methods used for assembling systems consisting of many liposomes with different functions, methods for achieving recursiveness and plasticity in chemical reaction systems, and methods for reconfiguring the network topology by liposome deformation are reviewed. Issues that must be addressed in order to realize chemical AI are also identified. [ABSTRACT FROM AUTHOR]

The paper presents a nonlinear coupled nonisothermal model of the process of material implementation into the target surface under conditions of surface treatment by a particle beam in the form of one or few consecutive pulses. The model takes into account the interaction of impurity diffusion, heat propagation, and mechanical disturbances, as well as the chemical reaction between the introduced impurity and the target material. The problem is solved numerically using an implicit symmetric difference scheme of the second‐order approximation in time and spatial coordinates. The results of solution are obtained for different time intervals. It was found that the interaction of different processes leads to the appearance of distortions in the front of waves. The distributions of temperature and impurity concentration have a wave character. The increment of the reaction product in the dynamics for different numbers of pulses is presented. The interaction mechanisms of the studied processes do not change and do not depend on the number of pulses. However, a more complicated picture is observed under treatment by several successive pulses due to the appearance of new extremes and distortions. [ABSTRACT FROM AUTHOR]

This paper describes the numerical solution of time dependent, two coupled substances in one‐dimensional field that participate in a chemical reaction with two kinds of different concentrations that affect each other. It is necessary to find the final state solution of the component variability concentrations in numerical form. The equations are conjugated and dependent on the radius and time (the existing physical model is a drop). In order to obtain a solution, we used the explicit method for the second‐order equation, which is very easy to program and understand, but requires some preliminary mathematical work. We examined the convergence of the solution in aspects of longitudinal (h) and lateral integration (s), as well as depending on the problem parameters. Thus, we have found that the (substances) components can reach an equilibrium state in which the concentrations would no longer change in time, or this state of equilibrium will not be existing due to the nature of the process and the concentrations will change in a cyclic or other form. Finally, qualitative support was found in literature. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids, which are used in nanotechnology, are advanced fluid classes with enriched thermal properties that produce superior outcomes than nanofluids. There are too many applications of hybrid nanofluids in engineering cosmetics, the automotive industry, the home industry, cancer treatment, textiles, paper plastics, paints, and soaps. The purpose of this study is to investigate the heat transfer rate of magnetohydrodynamic flow of Casson hybrid non‐Newtonian nanofluid across an enlarging surface. The current work focuses on magnetohydrodynamic hybrid nanoliquid flow across an extending 3‐D sheet. Additionally, zero mass flux and an adequate convective heating procedure are used as boundary conditions in this investigation. Blood serves as the base fluid, into which copper and alumina nanoparticles are dissolved to form a hybrid nanofluid. Adjusting the applicable similarity transformation, the present modeled equations are converted into dimensionless form. The Homotopy analysis approach (HAM) computes the resulting systems and illustrates them graphically to explain the flow behavior at the extending electrically conducting surface. Additionally, for changes in the non‐dimensional physical constraint values, the variations in physical quantities such as the skin friction, temperature, Nusselt number and velocity profiles are explained. The results of the current investigation demonstrated that a magnetic field and a non‐Newtonian parameter reduce the hybrid nanoliquid's velocity. The temperature profile goes up with thermophoresis and Brownian motion. The x−$x - $ component of velocity is found to fall as the stretching ratio parameter rises, while the component of velocity in the y−$y - $ direction experiences the opposite impact. When the parameters of a chemical reaction are adjusted upwards, the concentration profile deteriorates. It is originated that the rate at which heat is transferred by hybrid nanofluids is significantly more progressive than that of nanofluids. [ABSTRACT FROM AUTHOR]

The thermal decomposition characteristics and fuel oxidation mechanism of ammonium dinitramide (ADN)‐based liquid propellant are of great practical significance, but it is difficult to detect the whole intermediates and products using traditional experimental methods. In this paper, the thermal decomposition of ADN‐based liquid propellant at different temperatures (1500, 2000, 2500, and 3000 K) was simulated using the reactive molecular dynamics method. The effect of temperature on the thermal decomposition of propellant and the distribution of the main products were investigated. The results showed that the temperature played a role in promoting the decomposition of propellant. The main products of ADN‐based liquid propellant were N2, H2O, NH3, HNO3, ⋅NHO, CH2O, CO2, and NO2, while their evolution and generation pathways were also described in detail. The initial decomposition of ADN was the breakage of N−H bonds in ⋅NH4 or N−N/N−O bonds in ⋅N(NO2)2, and methanol generated free radicals by dehydrogenation. There was no direct chemical reaction between ADN and methanol, and the interaction was accomplished through the generation and consumption of free radicals. H2O provided a large amount of ⋅H and ⋅HO leading to a lower activation energy of ADN in propellant than that from reference. The overall reaction mechanism of the liquid propellant was deduced. The results would help to further investigate the reaction mechanism of ADN‐based liquid propellants. [ABSTRACT FROM AUTHOR]

Hydrothermal ore‐forming systems usually involve coupled processes among pore‐fluid flow, heat transfer, mass transport and chemical reactions in fluid‐saturated porous media. The finite element method (FEM) has provided a powerful tool to solve hydrothermal ore‐forming problems associated with pore‐fluid convective flow. Depending on different interests of research, a hydrothermal ore‐forming system may be simulated at two different length‐scale models, such as a regional (i.e., large length‐scale) model or a deposit (i.e., small length‐scale) model. However, there is an unsolved issue to guarantee the consistency between the applied boundary conditions to a deposit model and the predicted results, at exactly the same location as the boundary of the deposit model, from using the regional model. This paper proposes a FEM‐based dual length‐scale simulation procedure to address this issue. In the proposed procedure, a regional model of coarse mesh is first simulated by the FEM. Since a deposit model is located within the regional model, the applied boundary conditions to the deposit model of fine mesh can be determined from the simulation results of the regional model, so that the consistency can be guaranteed at the common boundary between the deposit model and the regional model. Main outcomes of this study have demonstrated that: (1) the proposed FEM‐based dual length‐scale simulation procedure is suitable and applicable for solving coupled problems involving pore‐fluid flow, heat transfer, mass transport and chemical reactions in fluid‐saturated porous media; (2) the proposed procedure is predictive because it is unnecessary to know the location of an ore deposit prior to the simulation of a hydrothermal ore‐forming system; (3) the boundary condition of a deposit model of fine mesh is consistent with the simulation results obtained from the regional model of coarse mesh, so that the reliability of the simulation results obtained from the deposit model can be ensured. [ABSTRACT FROM AUTHOR]

Mathcad is a simple‐to‐use and intuitive mathematical software that helps students to minimize the mathematical difficulties involved in solving engineering problems. The design of nonisothermal plug flow reactors (PFR) is a fundamental issue within the field of chemical reaction engineering; however, its teaching–learning process is hindered by students' mathematical difficulties in solving ordinary differential equations. In this paper, the software Mathcad was conveniently integrated into an educational experience through the resolution of two real case studies. In the first one, a simple liquid‐phase reaction is considered in a PFR working at different operating conditions, whereas the second case evaluates a PFR taking place multiple reactions (parallel reactions) with a heat exchanger attached. The assessment of this experience, which was held into two 5‐h Mathcad workshops, revealed that Mathcad made the design of non‐isothermal PFR more appealing, facilitated the understanding of the design process, and brought another dimension to the way the students perform complex calculations. [ABSTRACT FROM AUTHOR]