Reaction Mass Research Articles

Revealing the Role of Redox Reaction Selectivity and Mass Transfer in Current–Voltage Predictions for Ensembles of Photocatalysts

Photocatalysts are conceptually simple reaction units where nanoscale semiconductors integrated with catalysts drive a pair of redox reactions on illumination. However, the proximity of reaction sites performing cathodic and anodic reactions poses dire challenges to realize large light-to-fuel conversion efficiencies. In this study, a powerful, yet straightforward, equivalent-circuit detail-balance modeling framework is developed and applied to evaluate the performance of photocatalytic systems featuring multiple light absorbers. Specifically, low bandgap iridium-doped strontium titanate is modeled a Z-scheme photocatalyst to effect desired hydrogen evolution and iron-based redox shuttle oxidation reactions. Our model has unique capabilities to simulate competing redox reactions and address mass-transfer limitations. In a significant departure from state-of-the-art circuit models, our study develops tools to perform load-line analyses by incorporating a net electrochemical load curve that includes both desired and competing redox reactions. Consequently, reaction selectivity is predicted from equivalent circuit models for photocatalytic and photoelectrochemical systems. Our investigation into ensembles comprised of multiple, semi-transparent light absorbers reveals their potential to outperform a single, optically thick light absorber, particularly when operated under mass-transfer-limited conditions. However, this outcome hinges on minimizing mass-transfer rates of select redox species to prevent undesired reactions of hydrogen oxidation and/or redox shuttle reduction. Our findings demonstrate that reaction selectivity can be achieved by tuning asymmetry in redox species mass-transfer even with perfectly symmetric electrocatalytic charge-transfer coefficients. The influences of various kinetic, mass-transfer, and thermodynamic parameters are explored to offer crucial insights to inform the next-generation of photocatalysts, selective coatings, and reactor designs.

Elucidating Degradation of Aqueous Organic Redox Flow Batteries by Electrochemical Impedance Spectroscopy

Redox flow batteries, facilitating the dissociation of energy and power, emerge as a promising avenue for electrochemical electricity storage. A shift from vanadium flow batteries to those employing aqueous organic electroactive species is evident due to the latter's advantageous features, such as diverse design possibilities through functionalization, reduced cost, non-toxicity, and improved availability. Despite expectations that organic redox flow batteries can surpass a lifespan of 10 years or 2000 cycles, their practical long-term performance faces challenges arising from electrode, membrane, and organic species degradation. The intricate interplay of various degradation factors during full cell cycling results in observable capacity decay over cycles. Effectively mitigating degradation necessitates the dissection of these factors to identify the limiting component. Electrochemical impedance spectroscopy (EIS) emerges as a potent diagnostic tool capable of pinpointing and disentangling the sources of resistance within an electrochemical device. Through deconvolution of different factors, EIS allows for the quantitative measurement of resistance evolution throughout full cell cycling, reflecting degradation through changes in resistance. Consequently, by monitoring resistance evolution with EIS, the degradation rates of individual factors can be calculated.This study employs an alkaline aqueous organic redox flow battery with 2,5-di-tert-butyl-1,4-dihydroxybenzene sulfate (DHPS) as anolyte and ferrocyanide as catholyte for demonstration. EIS measurements are conducted at various cycles, and three distinct resistance components (charge transfer, ohmic, and mass transport) are identified as functions of cycle numbers. Subsequently, the degradation rates of crucial electrochemical parameters, such as reaction rate and mass transport coefficient, are quantified, providing essential inputs for subsequent modeling endeavors.

Recent advances in continuous flow synthesis of metal-organic frameworks and their composites.

Metal-organic frameworks (MOFs) and their composites have garnered significant attention in recent years due to their exceptional properties and diverse applications across various fields. The conventional batch synthesis methods for MOFs and their composites often suffer from challenges such as long reaction times, poor reproducibility, and limited scalability. Continuous flow synthesis has emerged as a promising alternative for overcoming these limitations. In this short review, we discuss the recent advancements, challenges, and future perspectives of continuous flow synthesis in the context of MOFs and their composites. The review delves into a brief overview of the fundamental principles of flow synthesis, highlighting its advantages over batch methods. Key benefits, including precise control over reaction parameters, improved scalability and efficiency, rapid optimization capabilities, enhanced reaction kinetics and mass transfer, and increased safety and environmental sustainability, are addressed. Additionally, the versatility and flexibility of flow synthesis techniques are discussed. The article then explores various flow synthesis methods applicable to MOF and MOF composite production. The techniques covered include continuous flow solvothermal synthesis, mechanochemical synthesis, microwave and ultrasound-assisted flow synthesis, microfluidic droplet synthesis, and aerosol synthesis. Notably, the combination of flow chemistry and aerosol synthesis with real-time characterization is also addressed. Furthermore, the impact of flow synthesis on the properties and performance of MOFs is explored. Finally, the review discusses current challenges and future perspectives in the field of continuous flow MOF synthesis, paving the way for further development and broader application of this promising technique.

Performance Characterization of a Radial Rotating Detonation Combustor with Axial Exhaust

Abstract This experimental study characterizes the performance of a radial rotating detonation combustor (RDC). An aerospike nozzle for rocket propulsion has been integrated into the center of the combustor, although the same combustor could also be coupled with turbomachinery. The radial RDC utilized a rapid to gradual (RTG) area change in the flow direction to effectively confine the detonation region close to the inlet plane and to improve the uniformity of the flow exiting the RDC. Three test cases were analyzed, (a) a baseline case at a total reactant mass flow rate, m˙ = 0.136 kg/s and equivalence ratio, ϕ = 0.6, (b) a higher reactant flow rate, m˙ = 0.318 kg/s and ϕ = 0.6, and (c) a higher ϕ = 0.8 at m˙ = 0.318 kg/s. All tests were conducted using methane and a 67% oxygen and 33% nitrogen (by mole) oxidizer mixture. Measurements were acquired using CTAP probes inside the combustion channel and along the aerospike to characterize the performance, PCB and ion probes near the detonation region to identify wave modes and their variations during the test, and thrust measurements using a six-axis force sensor. Results show highly complex wave modes with multiple co-rotating and/or counter-rotating waves depending upon the reactant flow rate. The pressure and thrust measurements are consistent with the wave mode analysis. In general, a positive (combustor only) pressure gain was inferred when losses associated with the injection system were excluded.

Continuum soil‐structure‐interaction model of the LHPOST6 shaking table reaction mass at UC San Diego

AbstractThe recently upgraded six Degree‐of‐Freedom Shaking Table, LHPOST6, at UC San Diego, underwent a series of forced vibration tests to evaluate the post‐upgrade dynamic response of the foundation‐soil system. The resulting data were instrumental in obtaining frequency response curves of the system, which were used to determine its low‐strain natural frequencies, effective viscous damping ratios, and reaction mass displacements. The extensive experimental data motivated the creation of a detailed Soil‐Structure‐Interaction model of the reaction mass‐soil system. The structure and soil were modeled using 3D Finite Elements in STKO‐OpenSees and calibrated with the acquired data via a parametric study. The 3D continuum FE model and the calibration procedure based on a single soil parameter (shear wave velocity profile) proved to be an effective tool to reproduce the experimental results accurately. This paper describes the Finite Element model, its calibration, and validation. In addition, the paper provides suggestions to simplify continuum models and promote their use in professional practice. The objectives of this campaign, alongside the growing accessibility of high‐performance computing, may serve as a step toward using SSI continuum models in the industry.

Selective electrochemical H2O2 production by a molecular copper catalyst: A crucial relation between reaction rate and mass transport

Selective electrochemical H2O2 production by a molecular copper catalyst: A crucial relation between reaction rate and mass transport

Comparison between EAST and ITER tokamak

This paper provides an overview of nuclear fusion, which is considered as an ideal energy source for the future, with emphasis on its theoretical foundation and tokamak device. In nuclear fusion, the mass of products is always less than the mass of reactants, and this mass defect is converted into enormous released energy. Scientists have proposed several ideas to reach such extreme conditions for nuclear fusion. Among these concepts, the tokamak device which uses magnetic fields to generate heat and confine high temperature plasma is probably the most promising one. Over the last half century, with the unremitting endeavor of building and operation a series of international tokamak projects, magnetic confinement fusion has made a lot of satisfactory successes. In this paper, two representative tokamak devices are discussed, which are International Thermonuclear Experimental Reactor (ITER) and Experimental Advanced Superconducting Tokamak (EAST), about their major difference and similarities between them. ITER is constructed with the cooperation of many countries, and it is the largest tokamak project which targets to prove nuclear fusion is commercially feasible. EAST is another tokamak device which is located in China and made great achievements of magnetic confinement nuclear fusion, such as the record-breaking plasma temperature.

Facile chemical surface modification of boron nitride platelets and improved thermal and mechanical properties of their polymer compounds for 2.5D/3D packaging applications

Thermally conductive yet electrically insulative epoxy composites are sought after as encapsulation materials to tackle the heat dissipation challenges in modern electronics. In this work, we developed a novel one-step and facile solvothermal reflux method using a high-boiling-point solvent to surface-modify hexagonal boron nitride (h-BN) with glycine. By refluxing glycine at high temperature, amino functional groups are grafted onto the BN surface, which can enhance the affinity of fillers for epoxy and reduce the interfacial thermal resistance of the filler/epoxy composites. We investigated the mechanism of glycine-grafted layer formation, optimizing reactant mass ratios for enhanced interfacial thermal transport. The resulting BN@G11/epoxy composites exhibit a remarkable thermal conductivity of 1.04 W/mK at 30 wt% modified-BN loading, representing a 477.8 % increase over neat epoxy and 57.5 % higher than h-BN/epoxy composites at equivalent BN filler loading. Additionally, these composites demonstrate improved thermomechanical properties, confirming the strengthened BN/epoxy interface bonding using modified BN fillers. Compared to other surface treatment methods, this solvothermal reflux approach stands out for its scalability and cost-effectiveness. This scalable and eco-friendly innovation presents a competitive strategy for designing polymer-based composites for thermal management, catering to the demands of future 2.5D/3D semiconductor packaging.

Development of a new heterogeneous catalyst based on triple superphosphate for the one-pot multicomponent synthesis via green strategy, accompanied by a critical assessment of environmental sustainability metrics applied to the synthesis of 2,4,5-tri and 1,2,4,5-tetra substituted imidazole heterocycle derivatives

A new catalyst, cerium phosphate (Ce(NO3)3/TSP), has been developed through a straightforward co-precipitation method. This catalyst was thoroughly characterized using techniques such as X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). The research focused on the application of Ce(NO3)3/TSP in the of 2,4,5-tri and 1,2,4,5-tetra substituted imidazole reaction with ammonium acetate, amine derivatives, benzil, and various aldehydes. The catalyst demonstrated outstanding performance, achieving product yields of 90-97% in just 8-10 minutes in an ethanol medium. The heterogeneity of the reaction was confirmed by a hot filtration test. This catalyst offers significant benefits, including easy recovery, reusability for at least five cycles, a simple work-up procedure, and high product yields. An evaluation of sustainability using green metrics such as the E-factor, atom economy (AE), reaction mass efficiency (RME), carbon efficiency (CE), and optimum efficiency (OE) indicated that this catalyst greatly enhances the environmental sustainability of the 2,4,5-tri and 1,2,4,5-tetra substituted imidazole reaction.

Cu-alginate hydrogels in microfluidic systems: a sustainable catalytic approach for click chemistry

This work explores the innovative use of copper-alginate (Cu-alginate) hydrogels within microfluidic systems to catalyze dipolar cycloaddition reactions, emphasizing green chemistry principles and process intensification. Utilizing naturally occurring biopolymers, such as alginates, provides an environmentally friendly alternative to conventional catalyst supports due to their biocompatibility, biodegradability, and effective metal ion immobilization capabilities. The integration of these biopolymer-based catalysts into microfluidic devices allows for precise control over reaction conditions, leading to enhanced reaction kinetics and mass transfer efficiencies. Our results demonstrate that Cu-alginate hydrogels effectively catalyze the formation of 1,4-disubstituted 1,2,3-triazoles through [3 + 2] dipolar cycloaddition reactions with high regioselectivity and conversion. The microfluidic setup ensures rapid and efficient synthesis, surpassing traditional batch reaction methods in both reaction rate and environmental impact by reducing solvent usage and waste generation. Furthermore, the use of microfluidics contributes to the reproducibility and scalability of the synthesis process, important for industrial applications. The model-based design and its simulations have been employed to further understand and optimize the reaction system. Diffusion through the gel layer and catalytic reaction kinetics estimated from experimental data were included in the model, providing a theoretical foundation for a comprehensive process evaluation. This study not only advances the field of sustainable catalysis by demonstrating the practical utility of biopolymer-supported catalysts in microfluidic systems, but also sets the stage for further research into biopolymer applications in complex chemical syntheses.

Numerical investigation on designs and performances of multi-dimensional forced convection flow field design of proton exchange membrane fuel cell

The geometric modification of the flow field is validated as an effective measure for improving proton exchange membrane fuel cell (PEMFC) performance and reactant mass transfer ability. In this paper, a parallel flow channel with X-structure connecting two adjacent channels is established. The multi-dimensional forced convection is formed by adding the stepped shape with three connecting flow fields to increase the performance and mass transfer capacity. Six cases based on the flow field of the X shaped channels are proposed to assess the impact of different designs. The results indicate that the X-structure design improves the uniformity of oxygen distribution and drainage capacity. A stepped design with gradually increasing height improves power density and generates a large area of localized gas vertical velocity. The addition of connecting channels results in different flow behaviors at the nodes, such as slight backflow, increased flow velocity, decreased water content, and temperature rise. With a power density improvement of up to 6.9 % compared to the initial flow field, cell performance improves as the order of step height rises and the diamond structure connection channels set. The innovative flow fields are supplied as a reference for future flow field design.

Evaluation of Terpene Decomposition in Kaffir Lime Juice during Storage Using Gas Chromatography-Mass Spectrometry and Proton Transfer Reaction-Mass Spectrometry.

Kaffir lime juice, often treated as production waste, can be a good source of terpenes. These compounds undergo various decomposition processes under the influence of external factors, especially during transportation and storage. In this paper, it was possible to monitor changes in the terpene profile of kaffir lime juice under different storage conditions, namely, 4 °C, 20 °C, and 35 °C. The identification of key decomposition products was achieved using gas chromatography-mass spectrometry (GC-MS) and a data mining protocol. It was followed by tracing those products in different storage conditions using a high-throughput proton transfer reaction mass spectrometry (PTR-MS) approach. Based on our findings, degradation pathways were presented, showing that the main products resulting from storage are p-cymene, p-cymenene, terpinene-4-ol, and α-terpineol. It was shown that conversion to p-cymenene occurs after 5 days of storage. Terpinene-4-ol and α-terpineol were found to be the final products of the conversion at all temperatures. Changes in the composition of terpenes are important from the point of view of their bioactive properties.

Study of Volatile Organic Compounds in Emission from Bottom Sediments of Three Lakes with Impact of Anthropopression Using the Proton Transfer Reaction Mass Spectrometry

Studies of volatile organic compounds (VOCs) emitted from the bottom sediments of three Pomeranian lakes in Poland: Łazienkowskie, Rychnowskie, and Jeleń were conducted. All three lakes are subject to anthropogenic pressure but to varying degrees. In 2021, bottom sediment samples were taken from the lakes studied and an analysis of the emission of 20 volatile organic compounds was carried out using a proton transfer reaction mass spectrophotometer (PTR-MS). Concentrations in emissions from the bottom sediments of VOCs with the following mass–charge ratio (m/z) were analyzed: 57, 61, 63, 69, 75, 81, 83, 85, 87, 95, 97, 99, 101, 109, 111, 127, 129, 137, 149, and 157. The obtained data were analyzed by performing statistical tests and multivariate cluster and PCA analysis. The analysis shows that the lowest concentrations of VOCs were observed from bottom sediments in Lake Jeleń, which is subject to the lowest anthropopressure among the studied lakes. The analysis shows that the lowest concentrations of VOCs were observed from bottom sediments in Lake Jeleń, which is subject to lower anthropopressure among the studied lakes. With the help of cluster analysis, it was possible to collect data on the VOC concentrations into clusters, which resulted in demonstrating similarities between Łazienkowskie and Rychnowskie lakes—lakes connected by an isthmus, and the different characteristics of Lake Jeleń. PCA analysis leads to similar observations. The tested m/z VOCs can be identified using additional analytical methods.

Effect of 2-hexanol and methanol on the <i>one-pot</i> process of dehydration and alkoxycarbonylation for the synthesis of esters

Objectives. To study the possibility of one-pot synthesis (combination of two processes in one reactor) for the following pairs of processes: (1) dehydration of 2-hexanol and isomerizing alkoxycarbonylation of the resulting 2-hexene, in order to obtain 2-hexyl heptanoate, and (2) dehydration of 2-hexanol and isomerizing methoxycarbonylation of the resulting 2-hexene, in order to obtain methyl esters of C7 carboxylic acids. To investigate the effect of the concentrations of 2-hexanol and methanol on the rate of the one-pot synthesis.Methods. One-pot synthesis was studied in a toluene medium in a steel batch reactor designed to operate at elevated pressure and equipped with a glass insert, a magnetic stirrer, a sampler, and gas input and discharge devices. Samples of the reaction mass were taken during the combined process and were analyzed by means of gas–liquid chromatography with a flame ionization detector.Results. The possibility of one-pot combination was demonstrated for 2-hexanol dehydration catalyzed by methanesulfonic acid, as well as for the isomerizing alkoxycarbonylation of the resulting 2-hexene with 2-hexanol and CO, catalyzed by the Pd(PPh3)2Cl2–XANTPHOS–methanesulfonic acid system. The dependencies of the rates of the dehydration of 2-hexanol and the formation of esters of C7 carboxylic acids on the concentration of 2-hexanol were shown to pass through a maximum. The possibility of the one-pot process was proved for the synthesis of esters from 2-hexanol, methanol, and CO with the predominant formation of heptanoic acid esters in the presence of the above catalytic system. The rates of dehydration of 2-hexanol and the formation of 2-hexyl esters of C7 carboxylic acids were found to decrease with increasing the concentration of methanol in the reaction mass. Under mild conditions (temperature 115°C, CO pressure 3 MPa) with the addition of methanol, the total fraction of 2-hexyl and methyl heptanoic acid esters among C7 carboxylic acid esters was determined to be 85.5%.Conclusions. The reactions of intramolecular acid–catalytic dehydration of 2-hexanol and isomerizing alkoxycarbonylation of the resulting 2-hexene, catalyzed by the Pd(PPh3)2Cl2–XANTPHOS–methanesulfonic acid system, can be performed as a one-pot process. Methanesulfonic acid simultaneously functions as a catalyst for the dehydration of 2-hexanol and a cocatalyst for the palladium–phosphine system for the alkoxycarbonylation of hexenes. In the presence of the Pd(PPh3) 2Cl2–XANTPHOS–methanesulfonic acid catalytic system, processes for the synthesis of heptanoic acid esters from 2-hexanol, methanol, and CO can be combined within one reactor. An increase in the methanol concentration negatively affects the rate of the dehydration of 2-hexanol and the formation of 2-hexyl esters of C7 carboxylic acids. A small amount of methanol in the reaction mass leads to an increase in the fraction of heptanoic acid esters among C7 carboxylic acid esters.

Shikonin blocks CAF-induced TNBC metastasis by suppressing mitochondrial biogenesis through GSK-3β/NEDD4-1 mediated phosphorylation-dependent degradation of PGC-1α

BackgroundTriple-negative breast cancer (TNBC) is characterized by its high metastatic potential, which results in poor patient survival. Cancer-associated fibroblasts (CAFs) are crucial in facilitating TNBC metastasis via induction of mitochondrial biogenesis. However, how to inhibit CAF-conferred mitochondrial biogenesis is still needed to explore.MethodsWe investigated metastasis using wound healing and cell invasion assays, 3D-culture, anoikis detection, and NOD/SCID mice. Mitochondrial biogenesis was detected by MitoTracker green FM staining, quantification of mitochondrial DNA levels, and blue-native polyacrylamide gel electrophoresis. The expression, transcription, and phosphorylation of peroxisome-proliferator activated receptor coactivator 1α (PGC-1α) were detected by western blotting, chromatin immunoprecipitation, dual-luciferase reporter assay, quantitative polymerase chain reaction, immunoprecipitation, and liquid chromatography-tandem mass spectrometry. The prognostic role of PGC-1α in TNBC was evaluated using the Kaplan–Meier plotter database and clinical breast cancer tissue samples.ResultsWe demonstrated that PGC-1α indicated lymph node metastasis, tumor thrombus formation, and poor survival in TNBC patients, and it was induced by CAFs, which functioned as an inducer of mitochondrial biogenesis and metastasis in TNBC. Shikonin impeded the CAF-induced PGC-1α expression, nuclear localization, and interaction with estrogen-related receptor alpha (ERRα), thereby inhibiting PGC-1α/ERRα-targeted mitochondrial genes. Mechanistically, the downregulation of PGC-1α was mediated by synthase kinase 3β-induced phosphorylation of PGC-1α at Thr295, which associated with neural precursor cell expressed developmentally downregulated 4e1 recognition and subsequent degradation by ubiquitin proteolysis. Mutation of PGC-1α at Thr295 negated the suppressive effects of shikonin on CAF-stimulated TNBC mitochondrial biogenesis and metastasis in vitro and in vivo.ConclusionsOur findings indicate that PGC-1α is a viable target for blocking TNBC metastasis by disrupting mitochondrial biogenesis, and that shikonin merits potential for treatment of TNBC metastasis as an inhibitor of mitochondrial biogenesis through targeting PGC-1α.

Phytochemical assisted engineering of silver nanoparticles on hexagonal boron nitride: An efficient nanocatalyst for amidation and reduction reactions in aqueous medium

Of the various intermediates studied in organic chemistry, the versatility of amides has been widely seen in pharmaceuticals. However, sustainable and simple hydration of nitriles to selectively yield amides is challenging. Thus, in our efforts to explore green methodologies in synthesizing amides, we developed a new and efficient nanocatalyst: biogenically synthesized silver nanoparticles supported on phytochemicals functionalized hexagonal boron nitride (h-BNCLE@AgNPs). The characterization of the h-BNCLE@AgNPs nanocatalyst confirmed the successful formation and immobilization of the silver nanoparticles on the support, which was surveyed for the amidation of nitriles in a base-free aqueous medium by selective hydrolysis. The aryl amides were obtained in good to excellent yields. Furthermore, the h-BNCLE@AgNPs nanocatalyst was successfully extended to the reduction of various mono and di-nitroarenes, where the h-BNCLE@AgNPs nanocatalyst showed very good performance. The heterogeneous nature of the nanocatalyst makes it easily recoverable from the reaction mass by simple filtration or centrifugation. The recycled nanocatalyst retained excellent catalytic activity even up to several recycles, demonstrating possible industrial applicability. The synthesis and applications of the h-BNCLE@AgNPs nanocatalyst are economical and facile, producing non-toxic by-products adhering to green chemistry protocol.

Sustainable Synthesis of the Active Pharmaceutical Ingredient Atenolol in Deep Eutectic Solvents.

Atenolol, one of the top five best-selling drugs in the world today used to treat angina and hypertension, and to reduce the risk of death after a heart attack, faces challenges in current synthetic methods to address inefficiencies and environmental concerns. The traditional synthesis of this drug involves a process that generates a large amount of waste and other by-products that need disposal. This study presents a one-pot DES-based sustainable protocol for synthesizing atenolol. The use of the DES allowed the entire process to be conducted with no need for additional bases or catalysts, in short reaction times, under mild conditions, and avoiding chromatographic purification. The overall yield of atenolol was 95%. The scalability of the process to gram-scale production was successfully demonstrated, emphasizing its potential in industrial applications. Finally, the 'greenness' evaluation, performed using the First Pass CHEM21 Metrics Toolkit, highlighted the superiority in terms of the atom economy, the reaction mass efficiency, and the overall process mass intensity of the DES-based synthesis compared with the already existing methods.

Comparative Analysis with Data Prediction of Non-linear Radiative Nano Second-Grade and Newtonian Fluid in Presence of Sinusoidal Magnetic Force

This study aims to enhance the comprehension of the fundamental fluid behavior by comparing Newtonian fluid with second-grade fluid under the influence of periodic magnetic fields, nonlinear radiative nanomaterial, and a porous stretched surface featuring a heat source. The governing equations' dimensionless forms are generated by applying the proper transformations, and the explicit finite difference (EFD) method is used to solve the numerically-derived solution while carefully maintaining stability and convergence standards. The results include velocity, heat, and mass transfer oscillation profiles; streamlines, and isothermal lines. Nusselt and Sherwood numbers are correlated with different factors according to tabular studies, and data prediction and regression are done using graphical representations. This study revealed that, in contrast to Newtonian fluid, second-grade fluid flow elevates velocity profiles with variations in chemical reaction parameters and mass Grashof numbers. Conversely, the thermal non-linear radiation and heat source in second-grade fluid particles effectively enhance the temperature field, although the temperature increase is more pronounced in Newtonian fluid compared to second-grade fluid. Also, second-grade fluid flow exhibits a lower mass transmission rate but higher stress sharing and heat transmission rates compared to Newtonian fluid flow. The implications of this research may impact prostate cancer treatment, as cancer patients have already benefited from the use of magnetic fields to regulate drug release from nanoparticles. Although the greater stress sharing and heat transmission rates may be used for targeted therapy, the lower mass transmission rate raises the possibility of benefits in controlled release scenarios.

Temperature control of sulfonation reaction in a semi-batch reactor

ABSTRACT Due to the basic dynamic nature of a batch or semi-batch reactor, during operation, the control duty may be altogether a set point tracking problem rather than a regulatory task with a fixed set point. In addition to that in a large number of exothermic reactor control, usually the reaction mass has to be raised to a higher temperature for initiation, and after the reaction sets in large amount of heat has to be extracted, so that the control system have the capabilities to heat as well as to cool the reaction mixture (like LAB Sulfonation). This may be done by manipulating the ratio of hot and cold streams of heat transfer fluids to make a mixed stream to be used as the heat transfer medium by using two 2-way control valves, and heating and cooling loads are splitted between them. The choice of this reactor type has been made on the basis of that the target system of our study is Sulfonation of Linear Alkyl Benzene (LAB) to synthesize the product, Linear Alkyl Benzene Sulfonic Acid (LABSA) which is the active species for manufacturing of domestic or industrial detergents. The reaction is essentially carried in semi-batch jacketed reactor.

Peanut Pairing Baijiu: To Enhance Retronasal Aroma Intensity while Reducing Baijiu Aftertaste.

Liquor-pairing food is a common dietary combination. Baijiu and peanuts are unquestionably a classic pairing in China. But no one has explained why. Its alteration in baijiu flavor was studied using multiple sensory evaluation, as well as nontargeted proton-transfer reaction mass spectrometry coupled with GC × GC-MS. Multiple statistical analyses were used to discover the changes in the retronasal aroma and its contribution to baijiu flavor. It showed that the consumption of peanuts enhances the burst intensity of ester aroma (0.814-1.00) and Jiao aroma (0.889-0.963) but decreases the aftertaste of baijiu (p < 0.05). Meanwhile, it increases the release intensity and advances the burst time of baijiu retronasal aroma (p < 0.05), suppressing its aftertaste through the retention effect of the food matrix, the changes in oral processing, and cross-modal interactions. Hydrophobicity, polarity, and chemical characteristics are key factors of the uneven impact of accompanying food to aroma compounds. Esters, especially ethyl caprylate (2103 ± 927 to 51.9 ± 4.05) is most impacted by peanuts and contributes most to baijiu flavor changes. Pyrazines from peanut enhance the Qu-aroma, grain aroma, and Chen aroma in baijiu flavor. Therefore, we revealed the chemical nature of baijiu-peanut combination and help to optimize baijiu consumption experience.