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Journal of Materiomics 2024年第4期10卷 937-946页

作者： Faris Sweidan Diogo ribeiro Costa Huan Liu Pär Olsson KTH royal Institute of Technology Nuclear EngineeringStockholm10691Sweden Westinghouse Electric Sweden AB Västerås72163Sweden

The temperature-dependent effective thermal conductivity of UN-X-UO_(2)(X=Mo,W)nuclear fuel composite was *** the experimental design,the thermal conductivity was calculated using Finite Element Modeling(FEM),and compared with analytical models for 10%,30%,50%,and 70%(in mass)uncoated/coated UN microspheres in a UO2 *** FEM results show an increase in the fuel thermal conductivity as the mass fraction of the UN microspheres increases from 1.2 to 4.6 times the UO2 reference at 2,000 *** results from analytical models agree with the thermal conductivity estimated by *** results also show that Mo and W coatings have similar thermal behaviors,and the coating thickness influences the thermal conductivity of the *** higher weight fractions,the thermal conductivity of the fuel composite at room temperature is substantially influenced by the high thermal conductivity coatings approaching that of ***,the thermal conductivity from FEM was used in the fuel thermal performance evaluation during LWr normal operation to calculate the maximum centerline *** results show a significant decrease in the fuel maximum centerline temperature ranging from−94 K for 10% UN to−414 K for 70%(in mass)UN compared to UO2 under the same operating conditions.

关键词： Accident tolerant fuel UN-X-UO_(2) Composite nuclear fuel Thermal conductivity Finite element modeling Thermal performance

Managing type 2 diabetes:targeting a microbial enzyme as a novel treatment option

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Signal Transduction and Targeted Therapy 2024年第1期9卷 3-5页

作者： Anikó Keller-Pintér Tamás Korcsmáros Tibor Vellai Department of Biochemistry Albert Szent-Györgyi Medical SchoolUniversity of SzegedSzeged6720Hungary Department of Metabolism Digestion and ReproductionImperial College LondonLondonW120NNUK Quadram Institute Bioscience Norwich Research ParkNorwichNR47UQUK Department of Genetics Eötvös Loránd University(ELTE)Budapest1117Hungary Hungarian research Network HUN-rEN-ELTE Genetics research Group Budapest1117Hungary

In a recent Science article,Wang and colleagues showed that the dipeptidyl peptidase 4(DPP4)enzyme produced by the gut microbiota can interfere with the effect of host glucagon-like peptide-1(GLP-1)involved in stimulating insulin secretion,and the specific inhibitor of microbial DPP4(mDPP4),combined with clinical inhibitors of host DPP4 isoenzymes,further promotes blood glucose homeostasis.1 These results point out why certain patients respond inadequately to an antidiabetic medication.

关键词： homeostasis stimulating clinical

Flat Band and η-Pairing States in a One-Dimensional MoiréHubbard Model

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Chinese Physics Letters 2024年第4期41卷 69-76页

作者：王冉宋智 College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China School of Physics Nankai UniversityTianjin 300071China

A Moirésystem is formed when two periodic structures have a slightly mismatched period,resulting in unusual strongly correlated states in the presence of particle-particle *** periodic structures can arise from the intrinsic crystalline order and periodic external *** investigate a one-dimensional Hubbard model with periodic on-site potential of period n_(0),which is commensurate to the lattice *** large n_(0),the exact solution demonstrates that there is a midgap flat band with zero energy in the absence of Hubbard *** Moiréunit cell contributes two zero energy levels to the flat *** the presence of Hubbard interaction,the midgap physics is demonstrated to be well described by a uniform Hubbard chain in which the effective hopping and on-site interaction strength can be controlled by the amplitude and period of the external *** simulations are performed to demonstrate the correlated behaviors in the finite-sized Moiré Hubbard system,including the existence of an η-pairing state and bound pair *** finding provides a method to enhance the correlated effect by a spatially periodic external field.

关键词： oscillation interaction field

A concise review on surface and structural modification of porous zeolite scaffold for enhanced hydrogen storage

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Chinese Journal of Chemical Engineering 2024年第6期70卷 33-53页

作者： B.A.Abdulkadir r.S.r.Mohd Zaki A.T.Abd Wahab S.N.Miskan Anh-Tam Nguyen Dai-Viet N.Vo H.D.Setiabudi Centre for research in Advanced Fluid&Processes Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Faculty of Chemical&Process Engineering Technology Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Center of Excellence for Green Energy and Environmental Nanomaterials(CE@GrEEN) Nguyen Tat Thanh University300A Nguyen Tat ThanhDistrict 4Ho Chi Minh City 755414Viet Nam

Investigating zeolites as hydrogen storage scaffolds is imperative due to their porous nature and favorable physicochemical ***,the storage capacity of the unmodified zeolites has been rather unsatisfactory(0.224%-1.082%(mass))compared to its modified ***,the contemporary focus on enhancing hydrogen storage capacities has led to significant attention towards the utilization of modified zeolites,with studies exploring surface modifications through physical and chemical treatments,as well as the integration of various active *** enhanced hydrogen storage properties of zeolites are attributed to the presence of aluminosilicates from alkaline and alkaline-earth metals,resulting in increased storage capacity through interactions with the charge density of these ***,there is a great demand to critically review their role such as well-defined topology,pore structure,good thermal stability,and tunable hydrophilicity in enhanced hydrogen *** article aimed to critically review the recent research findings based on modified zeolite performance for enhanced hydrogen *** of the factors affecting the hydrogen storage capacities of zeolites that can affect the rate of reaction and the stability of the adsorbent,like pressure,structure,and morphology were studied,and ***,future perspectives,recommendations,and directions for modified zeolites were discussed.

关键词： Zeolites Hydrogen storage Surface modification Adsorption Active metal

Psychosocial interventions for infertile couples:A scoping review

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Asian pacific Journal of reproduction 2024年第3期13卷 97-106页

作者： Sreemol Sunil Anish K.r. rajagiri College of Social Sciences KalamasseryKeralaIndia

Objective:To bring out current evidence regarding psycho-social interventions for infertility care,and identify the best practices in clinical ***:An in-depth literature review on infertility care intervention was conducted using data from multiple databases:PubMed,EMBASE,Google Scholar,and *** relevant articles selected were between 2008 and ***:A literature search turned up 1798 citations,of which 25 studies were included after rigorous *** intervention categories have been constantly utilised to provide support and promote mental health,of which acceptance and commitment therapy(ACT)and cognitive behaviour therapy(CBT)were used most *** interventions exhibited diversity in both content and composition,and addressed a wide range of ***:The review emphasizes that psycho-social interventions have a positive effect on psychological issues,relationships,and pregnancies among couples and can be incorporated into fertility-care practices.

关键词： Infertile couples Psychosocial interventions Mental health Quality of life

A Facial Expression recognition Method Integrating Uncertainty Estimation and Active Learning

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Computers, Materials and Continua 2024年第1期81卷 533-548页

作者： Wang Y. Zhang J. Sun r. School of Computer Science and Engineering Chongqing University of Technology Chongqing 400054 China Data Space research Institute of Hefei Comprehensive National Science Center Hefei 230088 China

The effectiveness of facial expression recognition (FEr) algorithms hinges on the model’s quality and the availability of a substantial amount of labeled expression data. However, labeling large datasets demands significant human, time, and financial resources. Although active learning methods have mitigated the dependency on extensive labeled data, a cold-start problem persists in small to medium-sized expression recognition datasets. This issue arises because the initial labeled data often fails to represent the full spectrum of facial expression characteristics. This paper introduces an active learning approach that integrates uncertainty estimation, aiming to improve the precision of facial expression recognition regardless of dataset scale variations. The method is divided into two primary phases. First, the model undergoes self-supervised pre-training using contrastive learning and uncertainty estimation to bolster its feature extraction capabilities. Second, the model is fine-tuned using the prior knowledge obtained from the pre-training phase to significantly improve recognition accuracy. In the pre-training phase, the model employs contrastive learning to extract fundamental feature representations from the complete unlabeled dataset. These features are then weighted through a self-attention mechanism with rank regularization. Subsequently, data from the low-weighted set is relabeled to further refine the model’s feature extraction ability. The pre-trained model is then utilized in active learning to select and label information-rich samples more efficiently. Experimental results demonstrate that the proposed method significantly outperforms existing approaches, achieving an improvement in recognition accuracy of 5.09% and 3.82% over the best existing active learning methods, Margin, and Least Confidence methods, respectively, and a 1.61% improvement compared to the conventional segmented active learning method. © 2024 The Authors.

关键词： active learning Expression recognition self-supervised learning uncertainty estimation

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.J.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Getting the Most Out of Every Training Day: The Influence of Instructors on Self-regulated Learning During Firefighter Leadership Courses

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International Journal of Disaster risk Science 2024年第3期15卷 332-345页

作者： Stefan r?seler Micha Hilbert Guido Hertel Meinald T.Thielsch Department of Psychology University of Münster

Leadership courses in the fire services are highly challenging, and they can seriously exhaust trainees and hamper their selfregulated learning efforts(for example, setting goals, focusing attention, seeking feedback). We theorize that experiences of failure or overload can curtail trainees' available energy resources on subsequent training days, which, in turn, should affect trainees' learning efforts. Given instructors' central role in leadership courses, we hypothesize that supportive and humble instructor behaviors decrease experiences of failure and overload and, thus, increase self-regulated learning. Moreover, we argue that supportive instructor behavior may amplify the positive effects of high energy resources, while humble behavior may alleviate the negative impact of low resource levels. We tested preregistered hypotheses with 118 firefighters participating in two-week leadership courses at a German fire academy. The participants completed short web-based questionnaires before and after classes each day. Multilevel analyses confirmed that perceived daily supportive and humble instructor behavior predicted trainees' reports of daily self-regulated learning activity. Notably, this effect was independent from positive effects of trainees' reported energy resources in the morning. Supportive and humble behavior did not moderate the eff ect of energy resources. Our findings suggest that instructors play a crucial role in facilitating effective learning under challenging training conditions. Furthermore, we offer implications for leaders in fire services, who often conduct trainings with their subordinates.

关键词： Diary study Fire services Instructor behavior Leadership training resource investment

Facilitated Prediction of Micropollutant Degradation via UV-AOPs in Various Waters by Combining Model Simulation and Portable Measurement

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Engineering 2024年第6期37卷 87-95页

作者： Yanyan Huang Mengkai Li Zhe Sun Wentao Li James r.Bolton Zhimin Qiang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Department of Civil and Environmental Engineering University of AlbertaEdmontonAB T6G 1H9Canada State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The degradation of micropollutants in water via ultraviolet(UV)-based advanced oxidation processes(AOPs)is strongly dependent on the water *** reactive radicals(rrs)formed in UV-AOPs have different reaction selectivities toward water matrices and degradation efficiencies for target ***,process selection and optimization are *** study developed a facilitated prediction method for the photon fluence-based rate constant for micropollutant degradation(K′_(p,MP))in various UV-AOPs by combining model simulation with portable *** methods for measuring the scavenging capacities of the principal rrs(rrSCs)involved in UV-AOPs(i.e.,HO^(·),SO_(4)^(·-),and Cl^(·))using a mini-fluidic photoreaction system were *** simulation models consisted of photochemical,quantitative structure–activity relationship,and radical concentration steady-state approximation *** rrSCs were determined in eight test waters,and a higher rrSC was found to be associated with a more complex water ***,by taking sulfamethazine,caffeine,and carbamazepine as model micropollutants,the k′_(p,MP) values in various UV-AOPs were predicted and further verified experimentally.A lower k′_(p,MP) was found to be associated with a higher rrSC for a stronger rr competition;for example,k′_(p,MP) values of 130.9 and 332.5 m^(2) einstein^(–1),respectively,were obtained for carbamazepine degradation by UV/H_(2)O_(2) in the raw water(rrSC=9.47×10^(4) s^(-1))and sand-filtered effluent(rrSC=2.87×10^(4) s^(-1))of a drinking water treatment *** developed method facilitates process selection and optimization for UV-AOPs,which is essential for increasing the efficiency and cost-effectiveness of water treatment.

关键词： UV-AOPs Micropollutant degradation reactive radicals Water matrix Model simulation

Stability Analysis of DC Microgrid Clusters Based on Step-by-step System Matrix Building Algorithm

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 900-912页

作者： K.Jithin N.Mayadevi r.Hari Kumar V.P.Mini the Department of Electrical Engineering College of Engineering TrivandrumAPJ Abdul Kalam Technological University(APJAKTU)ThiruvananthapuramIndia

DC microgrids(DCMGs)are made up of a network of sources and loads that are connected by a number of power electronic converters(PECs).The increase in the number of these PECs instigates major concerns in system *** interconnecting the microgrids to form a cluster,the system stability must be *** paper proposes a novel stepby-step system matrix building(SMB)algorithm to update the system matrix of an existing DCMG cluster when a new microgrid is added to the cluster through a distribution *** stability of the individual DCMGs and the DCMG cluster is analyzed using the eigenvalue ***,the particle swarm optimization(PSO)algorithm is used to retune the controller gains if the newly formed cluster is not *** simulation of the DCMG cluster is carried out in MATLAB/Simulink environment to test the proposed *** results are also validated using the OP4510 real-time simulator(rTS).

关键词： Converter DC microgrid cluster eigenvalue interconnection particle swarm optimization system stability system matrix