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Polyelectrolytes of Inorganic Polyoxometalates:Prospecting New Charged Polymers for Advanced Applications

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Chinese Journal of Polymer Science 2024年第9期42卷 1254-1269,I0005页

作者： de-Yin Wang Zhuo-Qun Lu Wei Wang College of Medical Linyi UniversityLinyi276000China Center for Synthetic Soft Materials Key Laboratory of Functional Polymer Materials of the Ministry of EducationInstitute of Polymer ChemistryNankai UniversityTianjin300071China

Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which possess special functions from the features of counterions,such as dissociation to charged species,mechanical stability,phase behavior,***,functional polyelectrolytes have been widely applied in many *** this perspective,we present some progresses in the studies of poly(polyoxometalate)s,denoted as poly(POM)s,as a kind of new charged polymers/polyelectrolytes,by covalent bonding between the inorganic polyoxometalate(POM)clusters and the organic polymer *** to the distinct positions of POMs in polymer chain and functions of poly(POM)s,they are divided into the following four categories:crosslinked poly(POM);side-chain poly(POM);backbone poly(POM),including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer;and POM-based covalent organic framework(PCOF).This perspective introduces the synthesis methods of poly(POM)polyelectrolytes and their macromolecular and aggregate structural characteristics,while also focusing on their properties and *** application areas include catalysis,thermal resistance,optical functions,fuel cells and batteries,etc.

关键词： Charged polymer Polyelectrolyte Polyoxometalate Poly(polyoxometalate) Covalent organic framework

Co-Optimization of Behind-the-Meter and Front-of-Meter Value Streams in Community Batteries

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 334-345页

作者： Carmen Bas Domenech Antonella Maria de Corato Pierluigi Mancarella University of Melbourne Parkville 2010VictoriaAustralia department of Electrical and Electronic Engineering The University of ManchesterManchesterU.K. IEEE

Community batteries(CBs)are emerging to support and even enable energy communities and generally help consumers,especially space-constrained ones,to access potential techno-economic benefits from storage and support local grid ***,the economic viability of CB projects is often *** this regard,typical feasibility studies assess CB value for behind-the-meter(BTM)operation or whole-sale market participation,i.e.,front-of-meter(FOM).This work proposes a novel techno-economic operational framework that allows systematic assessment of the different options and introduces a two-meter architecture that co-optimizes both BTM and FOM benefits.A real CB project application in Australia is used to demonstrate the significant two-meter co-optimization opportunities that could enhance the business case of CB and energy communities by multi-service provision and value stacking.

关键词： Behind-the-meter community battery distributed energy resource(deR) energy community front-of-meter value stacking

The effect of abiotic stresses on plant C:N:P homeostasis and their mitigation by silicon

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The Crop Journal 2024年第2期12卷 340-353页

作者： Milton Garcia Costa Renato de Mello Prado Luiz Fabiano Palaretti Jonas Pereira de Souza Júnior department of Agricultural Production Science School of Agricultural and Veterinarian SciencesSão Paulo State UniversityJaboticabalBrazil

In crop plants, various environmental stresses affect the balance of carbon, nitrogen, and phosphorus(C:N:P), leading to biochemical and physiological alterations and reductions in yield. Silicon(Si) is a beneficial element that alleviates plant stress. Most studies involving silicon have focused on physiological responses, such as improvements in photosynthetic processes, water use efficiency, and antioxidant defense systems. But recent research suggests that stressed plants facing either limited or excessive resources(water, light, nutrients, and toxic elements), strategically employ Si to maintain C:N:P homeostasis, thereby minimizing biomass losses. Understanding the role of Si in mitigating the impact of abiotic stresses on plants by regulating C:N:P homeostasis holds great potential for advancing sustainable agricultural practices in crop production. This review presents recent advances in characterizing the influence of environmental stresses on C:N:P homeostasis, as well as the role of Si in preserving C:N:P equilibrium and attenuating biological damage associated with abiotic stress. It underscores the beneficial effects of Si in sustaining C:N:P homeostasis and increasing yield via improved nutritional efficiency and stress mitigation.

关键词： Nutritional stoichiometry Elemental stoichiometry Beneficial element Environmental stresses Nutritional efficiency Carbon use efficiency Agricultural sustainability

A numerical model to simulate the transient frictional viscoelastic sliding contact

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Friction 2024年第2期12卷 319-339页

作者： Dongze WANG Gregory de BOER Anne NEVILLE Ali GHANBARZAdeH School of Mechanical Engineering University of LeedsLeeds LS29JTUK

Sliding motion has always been one of the major concerns when it comes to the analysis of viscoelastic contact problems.A new model simulating the transient sliding contact of smooth viscoelastic surfaces is developed in this *** taking the dry contact friction and the coupling between shear tractions and normal pressure into account,the effect of the early partial slip period,which is often neglected in the study of viscoelastic sliding contact problems,is investigated *** with solutions based on the frictionless assumption,the steady-state pressure profile is found to be slightly different under the effect of the partial slip regime,including a lower peak pressure and the shift of the contacting region in the direction opposite to the sliding ***,the time required for the viscoelastic contact to reach its steady state is delayed owing to the partial slip period preceding the global sliding motion.

关键词： contact mechanics frictional sliding viscoelasticity viscoelastic friction

Prediction models of burst strength degradation for casing with considerations of both wear and corrosion

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Petroleum Science 2024年第1期21卷 458-474页

作者： Jie-Li Wang Wen-Jun Huang de-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

Casing wear and casing corrosion are serious problems affecting casing integrity failure in deep and ultra-deep *** paper aims to predict the casing burst strength with considerations of both wear and ***,the crescent wear shape is simplified into three categories according to common mathematical ***,based on the mechano-electrochemical(M-E)interaction,the prediction model of corrosion depth is built with worn depth as the initial condition,and the prediction models of burst strength of the worn casing and corroded casing are ***,the accuracy of different prediction models is validated by numerical simulation,and the main influence factors on casing strength are *** last,the theoretical models are applied to an ultra-deep well in Northwest China,and the dangerous well sections caused by wear and corrosion are predicted,and the corrosion rate threshold to ensure the safety of casing is *** results show that the existence of wear defects results in a stress concentration and enhanced M-E interaction on corrosion depth *** accuracy of different mathematical models is different:the slot ring model is most accurate for predicting corrosion depth,and the eccentric model is most accurate for predicting the burst strength of corroded *** burst strength of the casing will be overestimated by more than one-third if the M-E interaction is neglected,so the coupling effect of wear and corrosion should be sufficiently considered in casing integrity evaluation.

关键词： deep well Casing integrity Casing wear Casing corrosion Burst strength

Methane cracking in molten tin for hydrogen and carbon production—a comparison with homogeneous gas phase process

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 155-166页

作者： Emmanuel Busillo Benedetta de Caprariis Maria Paola Bracciale Vittoria Cosentino Martina Damizia Gaetano Iaquaniello Emma Palo Paolo de Filippis Chemical Engineering department Sapienza University of RomeRome 00184Italy NextChem S.p.A. Rome 00156Italy

Methane cracking is considered a bridge technology between gray and green hydrogen production *** this work an experimental study of methane cracking in molten tin is *** tests were conducted in a quartz reactor(i.d.=1.5 cm,L=20 cm)with capillary injection,varying temperature(950–1070℃),inlet methane flow rate(30–60 mL·min^(-1))and tin height(0–20 cm).The influence of the residence time in the tin and in the headspace on methane conversion and on carbon morphology was *** conversions obtained in tin and in the empty reactor were measured and compared with results of detailed kinetic simulations(CRECK).Furthermore,an expression of a global kinetic constant for methane conversion in tin was also *** highest conversion(65%at Q_(0)=30 mL·min^(-1) and t=1070℃)is obtained for homogeneous gas phase reaction due to the long residence time(70 s),the presence of tin leads to a sharp decrease of residence time(1 s),obtaining a conversion of 35%at 1070℃,thus meaning that tin owns a role in the *** characterization(scanning electron microscopy,Raman)reported a change in carbon toward sheet-like structures and an increase of the carbon structural order in the presence of molten tin media.

关键词： methane cracking molten media H2 production carbon morphology

A convolutional neural network to detect possible hidden data in spatial domain images

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Cybersecurity 2024年第1期7卷 37-52页

作者： Jean de La Croix Ntivuguruzwa Tohari Ahmad department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African Center of Excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the ***,attackers with a steganalysis technique may break *** steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of Convolutional Neural Network(CNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based *** the existing CNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training *** research proposes a new method with a CNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain *** proposed method comprises three phases:pre-processing,feature extraction,and ***,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax *** results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis deep learning Convolutional neural network Infrastructure

Enhancing Indoor User Localization:An Adaptive Bayesian Approach for Multi-Floor Environments

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Computers, Materials & Continua 2024年第8期80卷 1889-1905页

作者： Abdulraqeb Alhammadi Zaid Ahmed Shamsan Arijit de Center for Artificial Intelligence and Robotics(CAIRO) Malaysia-Japan International Institute of TechnologyUniversiti Teknologi MalaysiaKuala Lumpur54100Malaysia department of Electrical Engineering College of EngineeringImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia department of Information Engineering Electronics and TelecommunicationsSapienza UniversityRome00185Italy

Indoor localization systems are crucial in addressing the limitations of traditional global positioning system(GPS)in indoor environments due to signal attenuation *** complex indoor spaces become more sophisticated,indoor localization systems become essential for improving user experience,safety,and operational *** localization methods based on Wi-Fi fingerprints require a high-density location fingerprint database,but this can increase the computational burden in the online *** networks,which integrate prior knowledge or domain expertise,are an effective solution for accurately determining indoor user *** networks use probabilistic reasoning to model relationships among various localization parameters for indoor environments that are challenging to *** article proposes an adaptive Bayesian model for multi-floor environments based on fingerprinting techniques to minimize errors in estimating user *** proposed system is an off-the-shelf solution that uses existing Wi-Fi infrastructures to estimate user’s *** operates in both online and offline *** the offline phase,a mobile device with Wi-Fi capability collects radio signals,while in the online phase,generating samples using Gibbs sampling based on the proposed Bayesian model and radio map to predict user’s *** results unequivocally showcase the superior performance of the proposed model when compared to other existing models and *** proposed model achieved an impressive lower average localization error,surpassing the accuracy of competing ***,this noteworthy achievement was attained with minimal reliance on reference points,underscoring the efficiency and efficacy of the proposed model in accurately estimating user locations in indoor environments.

关键词： Localization positioning Bayesian fingerprinting received signal strength(RSS)

Flow characteristics and bubble statistics during the fragmentation process of the ingested main cavity in plunging breaking waves

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Journal of Hydrodynamics 2024年第3期36卷 546-555页

作者： Wen-bin Zhang Wei-wen Zhao de-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Plunging breaking waves play an important role in the exchange of heat,momentum,and mass between the atmosphere and *** this paper,a series of direct numerical simulations is conducted to investigate the fragmentation process of the ingested main cavity in plunging breaking *** two-phase Navier-Stokes equations are solved using the finite-volume method based on adaptive refinement *** free surface is captured using a geometrical volume of fluid *** 2-D,3-D simulations are *** flow fields at different stages of wave breaking are presented and quantitative analysis for bubbles is *** 2-D instantaneous vorticity field and local velocity field are visualized to discuss the general flow characteristics during the fragmentation *** a 2-D parametric study is conducted to investigate the differences in the flow characteristics during the fragmentation process under different wave parameters including initial wave steepness(ε),Bond number(Bo),and Reynolds number(Re).3-D vortex structures are shown to further investigate the mechanisms behind the differences in the flow *** bubble size distributions under two different initial wave steepness are also discussed with their relationship to the fragmentation process of the ingested main *** research offers a significant understanding of the distinct procedures and fundamental dynamics involved in wave breaking,enhancing our comprehension of this intricate event.

关键词： Plunging breaking waves multiphase flow bubble statistics