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Approach for C_(1)to C_(2)products commencing from carbon dioxide:A brief review

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Petroleum 2024年第3期10卷 373-398页

作者： g.R.Dey Radiation and Photochemistry Division Bhabha Atomic Research CentreTrombayMumbai 400085India Homi bhabha National Institute AnushaktinagarMumbai 400094India

The carbon dioxide(CO_(2))conversion to useable compounds remains a great contest to scientists,engineers,and environmentalists with regard to the reverse of the oxidative degradation of *** conversion is essential for the development of complementary fuels and raw materials for various industries,which in turn will help in avoiding the drastic increase in tropospheric temperature due to greenhouse effect leading to global *** solar energy is the earth's essential power source along with the other various forms of energy for example fossil fuels,hydropower,wind,and biomaterials,*** final goal is to establish the artificial photosynthesis,which can be replicated thru various chemical reduction techniques of CO_(2)by employing appropriate photo-,thermal-and electro-catalysts in order to produce different one carbon atom(C_(1))and higher carbon atoms containing ***,the utilization of clean and sustainable CO_(2)towards high-value products is of great interest today due to the recognized environmental worries and subsequent lessening of the fossil fuels utilization load to meet the energy demand of *** way,solar energy can directly and/or indirectly be altered and stored in chemical energy form for industrial as well as societal *** this article our endeavor is to summarize the advances in CO_(2)chemical reduction research area till date especially in free radical-based methods such as electrochemical,photochemical and plasma chemical for the development of carbon species up to two carbon(C_(2))atoms containing products perceived in the chemical reduction of CO_(2).The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO_(2).

关键词： Photocatalysis Electrocatalysis Plasmolysis Thermolysis Carbon dioxide Chemical reduction

Rethinking global Context in Crowd Counting

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Machine Intelligence Research 2024年第4期21卷 640-651页

作者： guolei Sun Yun Liu thomas Probst Danda Pani Paudel Nikola Popovic Luc Van gool Computer Vision Lab ETH ZürichZürich 8092Switzerland Institute for Infocomm Research A*STARSingapore 138632Singapore Magic Leap Zürich 8050Switzerland

This paper investigates the role of global context for crowd ***,a pure transformer is used to extract features with global information from overlapping image *** by classification,we add a context token to the input sequence,to facilitate information exchange with tokens corresponding to image patches throughout transformer *** to the fact that transformers do not explicitly model the tried-and-true channel-wise interactions,we propose a token-attention module(TAM)to recalibrate encoded features through channel-wise attention informed by the context *** that,it is adopted to predict the total person count of the image through regression-token module(RTM).Extensive experiments on various datasets,including ShanghaiTech,UCFQNRF,JHU-CROWD++and NWPU,demonstrate that the proposed context extraction techniques can significantly improve the performanceover the baselines.

关键词： Crowd counting vision transformer global context attention density map.

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Jumping droplets

Droplet 2024年第2期3卷 3-33页

作者： Jonathan b.boreyko Department of Mechanical Engineering Virginia TechBlacksburgVirginiaUSA

When microdroplets with quasi-spherical contact angles coalesce together on a low-adhesion substrate,the capillary-inertial expansion of the liquid bridge induces a dramatic out-of-plane jumping event due to symmetry *** the onset of merging,droplet jumping initiates after a capillary-inertial time scale of tci∼1–100μs with characteristic jumping speeds of order vj∼0.1m/*** coalescenceinduced jumping-droplet effect is most commonly observed among a population of growing dew droplets on a superhydrophobic condenser,but can also occur by colliding deposited droplets together or during droplet sliding on fog *** this review,we cover the historical development of capillary-inertial jumping droplets,summarize the decade-long effort to rationalize the ultra-low energy conversion efficiency and critical droplet size of the phenomenon,and then present 15 variations on a theme of ***-inertial jumping droplets are not only a visceral illustration of the surprising power of surface tension at the microscale but they also have the potential to enhance phase-change heat transfer,enable selfcleaning surfaces,combat frost formation,harvest energy,and govern the rate of disease spread for wheat crops.

关键词： capillary illustration rational

On the Features of Thermal Convection in a Compressible gas

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Fluid Dynamics & Materials Processing 2024年第5期20卷 957-974页

作者： Igor b.Palymskiy Physics Department Siberian State University of Telecommunications and Information SciencesNovosibirsk City630102Russia Physics Department Siberian State University of Geosystems and TechnologiesNovosibirsk City630108Russia

The fully nonlinear equations of gas dynamics are solved in the framework of a numerical approach in order to study the stability of the steady mode of Rayleigh-bénard convection in compressible,viscous and heat-conducting gases encapsulated in containers with no-slip boundaries and isothermal top and bottom *** initial linear temperature profile is assumed.A map of the possible convective modes is presented assuming the height of the region and the value of the temperature gradient as influential *** a relatively small height,isobaric convection is found to take place,which is taken over by an adiabatic mode when the height exceeds the critical value,or by a super-adiabatic mode in case of a relatively high temperature *** the adiabatic mode,convective flow develops due to adiabatic processes given a stable initial *** analytic formula for the critical height of the region is derived taking into account and neglecting the dependence of the gas viscosity on the ***,an analytic formula is obtained for the upper boundary of the region of applicability of the boussinesq approximation for incompressible *** models for compressible gases are relevant to practical situations such as the study of convective flows in spatially extended gas mixtures when dealing with safety issues related to hydrocarbons stored in gas stations.A dangerous situation arises when the tank is almost empty but some hydrocarbon is left at the bottom of the *** the presence of convective flows,the vaporized fuel is mixed with the oxidizer(air)forming a gas-vapor ***,if the volumetric concentration of fuel vapor(hydrocarbon)is in the interval between the lower and upper concentration limits of ignition,then the gas-vapor mixture becomes explosive and any accidental spark is sufficient to cause an emergency.

关键词： Rayleigh-bénard convection gas stable stratification unstable stratification temperature gradient

Fuzzy Reliability and Availability of System under a Calendar-based Inspection Involving Multiple Failures and Its Application to Wind Turbine System

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 187-206页

作者： Mintu Kumar Himani Pant S.b.Singh Department of Mathematics Statistics and Computer Science G.B.Pant University of AgricultureTechnologyPantnagarUttarakhandIndia

Uncertainty is an important factor that needs to be considered while analyzing the performance of any engineering *** order to quantify uncertainty,fuzzy set theory is frequently used by most of researchers,including energy system *** to the classical reliability theory,component lifetimes have crisp parameters,but due to uncertainty and inaccuracy in data,it is sometimes very difficult to determine the exact values of these parameters in real-world *** overcome this difficulty in the current research,failure and repair rates were taken as triangular fuzzy numbers to determine the fuzzy availability of a system undergoing calendar-based periodic inspection subject to multiple failure modes(FMs).It was assumed that each component in the system had an exponential failure rate and repair rate with fuzzy *** FMs were explicitly taken into account when a functional state of the system was *** FM had a random failure *** the occurrence of any failure,a random time was selected for the relevant corrective repair *** proposed research was studied for one of the major sources of green energy,namely a wind turbine system wherein all the derived propositions have been implemented on it.

关键词： Fuzzy reliability fuzzy availability wind turbine system multiple failure modes triangular fuzzy number

Colorful facial markings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish

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Current Zoology 2024年第1期70卷 70-78页

作者： brett M.Culbert James b.barnett Isaac Y.Ligocki Matthew g.Salena Marian Y.L.Wong Ian M.Hamilton Sigal balshine Department of Integrative biology University of GuelphGuelphOntarioCanada Department of Psychology Neuroscience&BehaviourMcMaster UniversityHamiltonOntarioCanada Department of Evolution Ecologyand Organismal BiologyThe Ohio State UniversityColumbusOHUSA Department of biology Millersville UniversityMillersvillePAUSA School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia Department of Mathematics The Ohio State UniversityColumbusOHUSA

Many animals use color to signal their quality and/or behavioral *** signals have been well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well ***,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a brightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative *** with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory *** did not find any evidence that the size of these yellow patches was related to social rank or body size,but dominant males tended to have larger patches than dominant ***,patch size had a rank-specific relationship with the number of affiliative interactions that individuals engaged *** males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small ***,subordinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts *** together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.

关键词： affiliation foraging Lake Tanganyika Neolamprologus pulcher visual signals

Tracking the Ti^(4+)substitution in phlogopite by spectroscopic imaging:A tool for unravelling the growth of micas at HP-HT conditions

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geoscience Frontiers 2024年第3期15卷 1-13页

作者： g.Della Ventura N.El Moutaouakkil b.boukili S.bernardini A.Sodo L.Pronti M.Cestelli-guidi F.Holtz F.Lucci Dipartimento di Scienze UniversitàRoma TreRomaItaly INFN-LNF via Fermi 200040 FrascatiRomaItaly INgV Via di Vigna Murata 60500143 RomaItaly Laboratory of géosciences Water and Environment.Department of Earth Sciences.Faculty of SciencesUniversity Mohammed VRabatMorocco Leibnitz Universität Hannover Institute of MineralogyCallinstr 330167 HannoverGermany Dipartimento di Scienze della Terra e geoambientali Universitàdi Bari“Aldo Moro”BariItaly

Phlogopite solid-solutions have a wide pressure-temperature(P-T)stability field and are ubiquitous in a wide variety of geological settings,from deep lithosphere magmatic environments to upper crust metamorphic *** composition represents therefore a valuable physical-chemical archive and may provide important information regarding its crystallization and the petrogenesis of the *** this paper we examine the phlogopite phenocrysts from the well-known Fort Regent mica-bearing lamprophyre minette from ***(Island of Jersey,UK).Phlogopite phenocrystals from lamprophyres generally show normal-step and continuous compositional zoning,however those from the Fort Regent minette show a peculiar texture characterized by dark brown high-Ti(average TiO_(2)≈8.5 wt.%)cores enveloped by euhedral low-to mid-amplitude zonation due to oscillatory contents in Ti,Fe and ***-barometry modelling based on biotite-only composition yields relatively high P-T estimates(T≈970±54℃at P≈0.73±0.13 gPa)for cores whereas lower values(T≈790±54℃at P≈0.29±0.13 gPa)are obtained for the outer *** temperatures(T≈1075±54℃)but extremely high and anomalous pressure values(P≈1.82±0.13 gPa)are obtained for the yellowish inner *** combination of electron micro probe(EMP)analysis and single-crystal infra-red(FTIR)imaging in the OH-stretching region shows that the exceptional and oscillatory Ti contents are due to the Ti-vacancy substitution,typical of crystallization and growth processes of HP/HT *** imaging provides additional insight for this process,confirming the dominant dioctahedral nature for the Ti-Fe-rich cores and outer *** of thermobaric estimates obtained from the phlogopite compositiononly model,based on the fine-scale compositional evolution,shows that pressure-temperature values from low-Ti high-Mg domains should be carefully evaluated because the substitution mechanisms during the dark mica growth are not univocal

关键词： Ti-phlogopite Jersey minette(UK) Ti-substitution FTIR imaging Raman imaging Thermobarometric modelling

Nanozyme catalysis in a crowded environment:The impact of diffusion and surface shielding

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Nano Research 2024年第7期17卷 5795-5800页

作者： Vasily g.Panferov Juewen Liu Department of Chemistry Waterloo Institute for NanotechnologyWaterlooOntario N2L 3G1Canada

Nanozymes are widely used in various applications as nanosized catalysts for replacing *** accurate estimation of the catalytic activity of nanozymes in real conditions is *** this article,for the first time,we systematically studied the effect of macromolecular molecules co-existing in the real system on the oxidoreductase(peroxidase,oxidase,and catalase)-mimicking nanozymes made of a gold nanoparticle core and a platinum shell,Prussian blue,Mn_(2)O_(3) and CoO *** were made with horseradish *** distinguished two main mechanisms of the negative impact of macromolecules on nanozyme catalysis—slowed diffusion and surface shielding of *** the first mechanism is typical for enzymes,the second one is specific only for *** the mechanisms is essential for developing approaches to reduce the unavoidable impact of macromolecules for various analytical and biomedical applications.

关键词： molecular crowding biosensors nanoparticles

A simulation study on spatial and time resolution for a cost-effective positron emission particle tracking system

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Particuology 2024年第5期88卷 312-322页

作者： Josephine Oppotsch Matthias Steinke Miriam Fritsch Fritz-Herbert Heinsius thomas Held Nikoline Hilse Viktor Scherer Ulrich Wiedner Ruhr-Universität bochum Institut für Experimentalphysik I44801 BochumGermany Ruhr-Universität bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

This work is the second part of a simulation study investigating the processing of densely packed and moving granular assemblies by positron emission particle tracking (PEPT).Since medical positron emission tomography (PET) scanners commonly used for PEPT are very expensive,a PET-like detector system based on cost-effective organic plastic scintillator bars is being developed and tested for its *** this context,the spatial resolution of a resting positron source,a source moving on a freely designed model path,and a particle motion given by a discrete element method (DEM) simulation is studied using Monte Carlo simulations and the software toolkit *** not only extended the simulation and reconstruction to a moving source but also significantly improved the spatial resolution compared to previous work by adding oversampling and iteration to the reconstruction ***,in the case of a source following a trajectory developed from DEM simulations,a very good resolution of about 1 mm in all three directions and an average 3D deviation between simulated and reconstructed events of 2.3 mm could be ***,the resolution for realistic particle motion within the generic grate system (which is the test rig for further experimental studies) is well below the smallest particle *** simulation of the dependence of the reconstruction accuracy on tracer particle location revealed a nearly constant efficiency within the entire detector system,which demonstrates that boundary effects can be neglected.

关键词： Positron emission particle tracking Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)