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Technological achievements in the fabrication of tubular-designed protonic ceramic electrochemical cells

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Materials Futures 2024年第4期3卷 71-106页

作者： Maria A Gordeeva Artem p Tarutin Nikolai A Danilov Dmitry A Medvedev Laboratory of Electrochemical Devices Based on Solid Oxide proton Electrolytes Institute of High-Temperature Electrochemistry620066 EkaterinburgRussia Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia

protonic ceramic electrochemical cells provide an excellent basis for the advancement of high-temperature solid oxide devices,offering potential solutions to a range of challenges in the hydrogen energy and carbon capture *** facilitated ionic transport in proton-conducting electrolytes enables these cells to operate at temperatures 100◦C–500◦C lower than those of conventional solid oxide cells with known zirconia *** a result,promising performances have been reported for various types of proton ceramic electrochemical ***,these advancements have been demonstrated only at the laboratory scale,whereas their ZrO2-based counterparts have already been *** review presents an overview of the fundamental and applied aspects related to the fabrication of tubular protonic ceramic electrochemical cells and their subsequent characterization as hydrogen permeation membranes,hydrogen pumps,hydrogen sensors,fuel cells,electrolysis cells,and electrochemical reactors.A specific focus is placed on the technological aspects of the tube preparations derived from the original powder sources as well as the dimensional characteristics of the tubes,which serve as an indicator of ***,this review serves as a starting point for the development and scaling of protonic ceramic electrochemical cells,with the potential for large-scale production.

关键词： electrochemistry energy conversion hydrogen proton transport perovskite solid oxide cells scaling

Enantioselective iridium-catalyzed allylic substitution with a Reformatsky reagent: direct construction of β-stereogenic homoallylic esters

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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： Debasis pal Kirana D.Veeranna Yuk Fai Wong p.Andrew Evans Department of Chemistry Queen's University Xiangya School of pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

Bile acid signaling in the regulation of whole body metabolic and immunological homeostasis

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Science China(Life Sciences) 2024年第5期67卷 865-878页

作者： Wei Jia Yitao Li Kenneth C.p.Cheung Xiaojiao Zheng School of Chinese Medicine Hong Kong Baptist UniversityHong KongChina Center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai JiaoTong University School of MedicineShanghai 200233China

Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune *** the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing *** allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune *** review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and *** BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.

关键词： bile acid whole body metabolism immunity

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar K.p.Vijayakumar K.pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Effect of dry-wet cycles on dynamic properties and microstructures of sandstone:Experiments and modelling

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International Journal of Mining Science and Technology 2024年第5期34卷 655-679页

作者： Hai pu Qingyu Yi Andrey p.Jivkov Zhengfu Bian Weiqiang Chen Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Earth Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China Department of Solids and Structures School of EngineeringUniversity of ManchesterManchester M139PLUK School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Department of Civil and Environmental Engineering Rice UniversityHouston 77005USA State Key Laboratory of High performance Civil Engineering Materials Jiangsu Research Institute of Building Science Co.Ltd.Nanjing 210008China Department of Materials University of OxfordOxford OX13PHUK

Underground pumped storage power plant(UpSp)is an innovative concept for space recycling of abandoned *** realization requires better understanding of the dynamic performance and durability of reservoir *** paper conducted ultrasonic detection,split Hopkinson pressure bar(SHpB)impact,mercury intrusion porosimetry(MIp),and backscatter electron observation(BSE)tests to investigate the dynamical behaviour and microstructure of sandstone with cyclical dry-wet damage.A coupling FEM-DEM model was constructed for reappearing mesoscopic structure *** results show that dry-wet cycles decrease the dynamic compressive strength(DCS)with a maximum reduction of 39.40%,the elastic limit strength is reduced from 41.75 to 25.62 *** sieved fragments obtain the highest crack growth rate during the 23rd dry-wet cycle with a predictable life of 25 cycles for each rock *** pore fractal features of the macropores and micro-meso pores show great differences between the early and late cycles,which verifies the computational statistics analysis of particle *** numerical results show that the failure patterns are governed by the strain in pre-peak stage and the shear cracks are *** dry-wet cycles reduce the energy transfer efficiency and lead to the discretization of force chain and crack fields.

关键词： Underground pumped storage power plant Dry-wet cycles Split Hopkinson pressure bar Macro and micro properties FEM-DEM coupling model Damage characterization

Solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHpA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： p.A.Martínez-Montoya R.G.Sanchez-Alvarado D.Y.Medina-Velazquez M.L.Carrera-Jota p.Garnica-Chávez A.de J.Morales-Ramirez Higher School of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHpA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHpA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery Rare earth solid-liquid extraction XAD-7 resin Fluorescent lamps recycling Solid-liquid kinetics extraction

Laser-induced graphene-coated wearable smart textile electrodes for biopotentials signal monitoring

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Frontiers of Materials Science 2024年第1期18卷 95-111页

作者： C.M.Vidhya Yogita Maithani Sakshi Kapoor J.p.Singh Department of physics Indian Institute of Technology DelhiHauz KhasNew Delhi 110016India

This paper describes how to produce a wearable dry electrode at a reasonable cost and how to use it for the monitoring of biopotentials in *** textiles in wearable technologies have made a great advancement in the health care management and living standards of *** was manufactured using the low-cost single-step process,laser ablation of polyimide,a commercial *** dispersions were made using solvent isopropyl alcohol which has low boiling point,nontoxicity,and environmental *** successive coating of the graphene dispersion on the cotton fabric to make it conductive,the sheet resistance of the resulting fabric dropped to 3% of its initial *** laser-induced graphene(LIG)cotton dry electrodes thus manufactured are comparable to Ag/AgCl wet electrodes in terms of the skin-to-electrode impedance,measuring between 78.0 and 7.2 kΩ for the frequency between 40 Hz and 1 *** LIG cotton electrode displayed a signal-to-noise ratio of 20.17 *** to its comfort,simplicity,and good performance over a longer period of time,the textile electrode appears suited for medical applications.

关键词： biopotential electrocardiogram electromyogram flexible electrode textile porous graphene

Investigation of Microstructure, Microhardness and Thermal properties of Ag-In Intermetallic Alloys prepared by Vacuum Arc Meltings

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 182-187页

作者： ÇELİK Erçevik ATA ESENER pınar ÖZTÜRK Esra AKSÖZ Sezen Nevşehir HacıBektaşVeli University Department of Physics50300NevşehirTurkey Erciyes University Graduate School of Natural and Applied Sciences38039KayseriTurkey Kocaeli University Department of Physics41380KocaeliTurkey

Ag-In intermetallic alloys were produced by using vacuum arc furnace. Differential Scanning Calorimetry(DSC) and Energy Dispersive X-Ray Spectrometry(EDX) were used to determine the thermal properties and chemical composition of the phases respectively. Microhardness values of Ag-In intermetallics were calculated with Vickers hardness measurement method. According to the experimental results, Ag-34 wt%In intermetallic system generated the best results of energy saving and storage compared to other intermetallic systems. Also from the microhardness results, it was observed that intermetallic alloys were harder than pure silver and Ag-26 wt%In system had the highest microhardness value with 143.45 kg/mm^(2).

关键词： thermal properties microstructure characterization microhardness alloys material characterization

Technological advancements in millet dehulling and polishing process: An insight into pretreatment methods, machineries and impact on nutritional quality

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Grain & Oil Science and Technology 2024年第3期7卷 186-195页

作者： Shagolshem Mukta Singh Jayasree Joshi T p.Srinivasa Rao Agricultural and Food Engineering Department Indian Institute of Technology KharagpurKharagpurWest Bengal 721302India

Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions in millet dehulling and polishing. These technologies operate based on the fundamental principles of compression-shearing, abrasion-friction, and centrifugal-impact forces. processing of millets can be challenging because of the physical characteristics and tight attachment of hull and bran to the endosperm. However, several dehullers have been designed to solve this problem for different kinds of millets. In addition, the nutritional and anti-nutritional characteristics undergo alterations due to both dehulling and polishing processes. These alterations are thoroughly examined and discussed in this article. Specifically, anti-nutrients such as tannins and phytate are predominantly found in the outer pericarp of the grain and experience a reduction after undergoing dehulling and polishing. The nutritional properties are also subjected to a reduction;however, this reduction can be mitigated by subjecting the grains to certain pretreatments before dehulling and polishing. These treatments serve to enhance dehulling efficiency and nutrient digestibility while simultaneously reducing the presence of anti-nutrients. Novel thermal and non-thermal methodologies such as microwave, hydrothermal, high-pressure processing, and ohmic heating can be employed for processing millets, thereby diminishing the loss of nutrients. Additional research can be carried out to investigate their impact on the dehulling and polishing of millets.

关键词： Millets Dehulling polishing pretreatment Novel thermal and non-thermal techniques