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Cyclic Rhythms and Macroheterogenity of the Carbonated Intersaliferous Reservoirs in the Pripiat Basin (Byelorussia)
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作者 Christophe Kaki Gerard Alfred Franck d’Almeida +2 位作者 Nicaise Yalo Anatoli Pavlovich Ryjkov Evgeni Ivanovich Taranenko 《Open Journal of Geology》 2012年第2期91-102,共12页
The intersaliferous complex of the Pripiat basin was deposited during a rift stage that occurred at Hercynian cycle. Reef formations are locally present within this complex, proof that the basin had undergone signific... The intersaliferous complex of the Pripiat basin was deposited during a rift stage that occurred at Hercynian cycle. Reef formations are locally present within this complex, proof that the basin had undergone significant variations of tectonic regime during sedimentation processes. The natural reservoirs rocks of this complex consist essentially of biogenic, bioclastic limestones and dolomites which had suffered important diagenetics transformations. The vertical succession of these reservoirs rocks point up the existence of cycles quantified by the mathematical methods of autocorrelation and spectral analysis. The application of appointed mathematical methods for interpretation of neutron gamma logs of natural reservoirs intervals allowed the structuring of studied oil fields in linear hydrodynamic blocks proved by the water injections made with intention to maintain reservoirs pressure during fields’ exploitation. 展开更多
关键词 Pripiat BASIN Natural RESERVOIRS HETEROGENEITY AUTOCORRELATION Spectral Analysis
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Silicon-based optoelectronic heterogeneous integration for optical interconnection
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作者 李乐良 李贵柯 +5 位作者 张钊 刘剑 吴南健 王开友 祁楠 刘力源 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期1-9,共9页
The performance of optical interconnection has improved dramatically in recent years.Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection,which ... The performance of optical interconnection has improved dramatically in recent years.Silicon-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection,which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip,but also improves the system performance through advanced heterogeneous integrated packaging.This paper reviews recent progress of silicon-based optoelectronic heterogeneous integration in high performance optical interconnection.The research status,development trend and application of ultra-low loss optical waveguides,high-speed detectors,high-speed modulators,lasers and 2D,2.5D,3D and monolithic integration are focused on. 展开更多
关键词 silicon-based heterogeneous integration heterogeneous integrated materials heterogeneous integrated packaging optical interconnection
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Pumping-induced Well Hydraulics and Groundwater Budget in a Leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties
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作者 ZHUANG Chao LÜChenyang +5 位作者 YAN Long LI Yabing ZHOU Zhifang WANG Jinguo DOU Zhi Walter A.ILLMAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期477-490,共14页
In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is... In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical analysis.Analytical investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard depletion.Locations of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater budget.In the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer drawdown.When using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to calculate aquitard depletion and unconfined aquifer leakage. 展开更多
关键词 HYDROGEOLOGY AQUITARD vertical heterogeneity semi-analytical solution well hydraulics groundwater budget
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Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds
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作者 Shuang Luo Tie Shu +6 位作者 Min Mao Haijie Yu Yuxin Zheng Daqian Ding Lingmei Liu Kexin Yao Jianjian Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期311-321,共11页
Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low e... Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction conditions.Here,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal method.Remarkably,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction conditions.The yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO. 展开更多
关键词 Biomass FRUCTOSE 1 2-PROPANEDIOL Retroaldol condensation Heterogenous catalysis
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A geochemical perspective on the genesis of Cenozoic basic volcanism in northeastern Turkey:an overview of metasomatism and heterogeneity of the sub-continental lithospheric mantle in a post-collisional setting
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作者 Mehmet Arslan Irfan Temizel 《Acta Geochimica》 EI CAS CSCD 2024年第3期489-506,共18页
The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of su... The post-collisional Cenozoic basic volcanic rocks in NE Turkey show temporal variations in whole-rock lithophile element and highly siderophile element(HSE)systematics that are mainly associated with the nature of sub-continental lithospheric mantle(SCLM)sources and parental melt generation.So far,the traditional whole-rock lithophile geochemical data of these basic volcanic rocks have provided important constraints on the nature of SCLM sources.Integrated lithophile element and HSE geochemical data of these basic volcanic rocks also reveal the heterogeneity of the SCLM source,which is principally related to variable metasomatism resulting from previous subduction(s)and post-collisional mantle-crust interactions in an extensional setting.Lithophile element geochemical features suggest that the parental magmas have derived from metasomatized spinel-to garnet-bearing SCLM sources for Eocene and Miocene basic volcanic rocks with subduction signatures whereas originated from spinel-to garnet-bearing SCLM sources for Mio-Pliocene and Plio-Quaternary basaltic volcanic rocks without the subduction signature.Lithophile element and HSE geo-chemistry also reveal that Eocene and Miocene basic vol-canic rocks were affected by more pronounced crustal contamination than the basaltic volcanic rocks of Mio-Pliocene and Quaternary.Furthermore,the integrated lithophile element and HSE compositions of these basic volcanic rocks,together with the regional asymmetric lithospheric delamination model,reveal that the compositional variation(especially due to metasomatism)was significant temporally in the heterogeneity of the SCLM sources from which parental magmas formed during the Cenozoic era. 展开更多
关键词 BASALT Lithospheric mantle METASOMATISM Mantle heterogeneity Cenozoic volcanics NE Turkey
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Insight into the spoilage heterogeneity of meat-borne bacteria isolates with high-producing collagenase
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作者 Haodong Wang Liangting Shao +3 位作者 Jinhao Zhang Xinglian Xu Jianjun Li Huhu Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1402-1409,共8页
Chilled chicken is inevitably contaminated by microorganisms during slaughtering and processing,resulting in spoilage.Cutting parts of chilled chicken,especially wings,feet,and other skin-on products,are abundant in c... Chilled chicken is inevitably contaminated by microorganisms during slaughtering and processing,resulting in spoilage.Cutting parts of chilled chicken,especially wings,feet,and other skin-on products,are abundant in collagen,which may be the primary target for degradation by spoilage microorganisms.In this work,a total of 17 isolates of spoilage bacteria that could secrete both collagenase and lipase were determined by raw-chicken juice agar(RJA)method,and the results showed that 7 strains of Serratia,Aeromonas,and Pseudomonas could significantly decompose the collagen ingredients.The gelatin zymography showed that Serratia liquefaciens(F5)and(G7)had apparent degradation bands around 50 kDa,and Aeromonas veronii(G8)and Aeromonas salmonicida(H8)had a band around.65 and 95 kDa,respectively.The lipase and collagenase activities were detected isolate-by-isolate,with F5 showing the highest collagenase activity.For spoilage ability on meat in situ,F5 performed strongest in spoilage ability,indicated by the total viable counts,total volatile basic nitrogen content,sensory scores,lipase,and collagenase activity.This study provides a theoretical basis for spoilage heterogeneity of strains with high-producing collagenase in meat. 展开更多
关键词 BACTERIA Chilled chicken HETEROGENEITY COLLAGENASE SPOILAGE
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Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review
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作者 Bo Han Weishi Liang +4 位作者 Yong Hai Duan Sun Hongtao Ding Yihan Yang Peng Yin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期563-570,共8页
Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the i... Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal deformity.With the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and behavior.Very few studies have been published on the specific characteristics of distraction spinal cord injury.In this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this disease.In addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord injury.We provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease. 展开更多
关键词 animal models behavior DISTRACTION heterogeneity HISTOLOGY mechanism NEUROPHYSIOLOGY spinal cord injury systematic review tension
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Dynamics and synchronization in a memristor-coupled discrete heterogeneous neuron network considering noise
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作者 晏询 李志军 李春来 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期537-544,共8页
Research on discrete memristor-based neural networks has received much attention.However,current research mainly focuses on memristor–based discrete homogeneous neuron networks,while memristor-coupled discrete hetero... Research on discrete memristor-based neural networks has received much attention.However,current research mainly focuses on memristor–based discrete homogeneous neuron networks,while memristor-coupled discrete heterogeneous neuron networks are rarely reported.In this study,a new four-stable discrete locally active memristor is proposed and its nonvolatile and locally active properties are verified by its power-off plot and DC V–I diagram.Based on two-dimensional(2D)discrete Izhikevich neuron and 2D discrete Chialvo neuron,a heterogeneous discrete neuron network is constructed by using the proposed discrete memristor as a coupling synapse connecting the two heterogeneous neurons.Considering the coupling strength as the control parameter,chaotic firing,periodic firing,and hyperchaotic firing patterns are revealed.In particular,multiple coexisting firing patterns are observed,which are induced by different initial values of the memristor.Phase synchronization between the two heterogeneous neurons is discussed and it is found that they can achieve perfect synchronous at large coupling strength.Furthermore,the effect of Gaussian white noise on synchronization behaviors is also explored.We demonstrate that the presence of noise not only leads to the transition of firing patterns,but also achieves the phase synchronization between two heterogeneous neurons under low coupling strength. 展开更多
关键词 heterogeneous neuron network discrete memristor coexisting attractors SYNCHRONIZATION noise
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Blockchain-Enabled Cybersecurity Provision for Scalable Heterogeneous Network:A Comprehensive Survey
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作者 Md.Shohidul Islam Md.Arafatur Rahman +3 位作者 Mohamed Ariff Bin Ameedeen Husnul Ajra Zahian Binti Ismail Jasni Mohamad Zain 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期43-123,共81页
Blockchain-enabled cybersecurity system to ensure and strengthen decentralized digital transaction is gradually gaining popularity in the digital era for various areas like finance,transportation,healthcare,education,... Blockchain-enabled cybersecurity system to ensure and strengthen decentralized digital transaction is gradually gaining popularity in the digital era for various areas like finance,transportation,healthcare,education,and supply chain management.Blockchain interactions in the heterogeneous network have fascinated more attention due to the authentication of their digital application exchanges.However,the exponential development of storage space capabilities across the blockchain-based heterogeneous network has become an important issue in preventing blockchain distribution and the extension of blockchain nodes.There is the biggest challenge of data integrity and scalability,including significant computing complexity and inapplicable latency on regional network diversity,operating system diversity,bandwidth diversity,node diversity,etc.,for decision-making of data transactions across blockchain-based heterogeneous networks.Data security and privacy have also become the main concerns across the heterogeneous network to build smart IoT ecosystems.To address these issues,today’s researchers have explored the potential solutions of the capability of heterogeneous network devices to perform data transactions where the system stimulates their integration reliably and securely with blockchain.The key goal of this paper is to conduct a state-of-the-art and comprehensive survey on cybersecurity enhancement using blockchain in the heterogeneous network.This paper proposes a full-fledged taxonomy to identify the main obstacles,research gaps,future research directions,effective solutions,andmost relevant blockchain-enabled cybersecurity systems.In addition,Blockchain based heterogeneous network framework with cybersecurity is proposed in this paper tomeet the goal of maintaining optimal performance data transactions among organizations.Overall,this paper provides an in-depth description based on the critical analysis to overcome the existing work gaps for future research where it presents a potential cybersecurity design with key requirements of blockchain across a heterogeneous network. 展开更多
关键词 Blockchain CYBERSECURITY data transaction diversity heterogeneous
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Synergy of heterogeneous Co/Ni dual atoms enabling selective C-O bond scission of lignin coupling with in-situ N-functionalization
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作者 Baoyu Wang Jinshu Huang +3 位作者 Hongguo Wu Ximing Yan Yuhe Liao Hu Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期16-25,共10页
Selective cleavage of Csp^(2)-OCH_(3)bond in lignin without breaking other types of C-O bonds followed by N-functionalization is fascinating for on-purpose valorization of biomass.Here,a Co/Ni-based dual-atom catalyst... Selective cleavage of Csp^(2)-OCH_(3)bond in lignin without breaking other types of C-O bonds followed by N-functionalization is fascinating for on-purpose valorization of biomass.Here,a Co/Ni-based dual-atom catalyst CoNiDA@NC prepared by in-situ evaporation and acid-etching of metal species from tailor-made metal–organic frameworks was efficient for reductive upgrading of various lignin-derived phenols to cyclohexanols(88.5%–99.9%yields),which had ca.4 times higher reaction rate than the single-atom catalyst and was superior to state-of-the-art heterogeneous catalysts.The synergistic catalysis of Co/Ni dual atoms facilitated both hydrogen dissociation and hydrogenolysis steps,and could optimize adsorption configuration of lignin-derived methoxylated phenols to further favor the Csp^(2)-OCH_(3)cleavage,as elaborated by theoretical calculations.Notably,the CoNi_(DA)@NC catalyst was highly recyclable,and exhibited excellent demethoxylation performance(77.1%yield)in real lignin monomer mixtures.Via in-situ cascade conversion processes assisted by dual-atom catalysis,various high-value N-containing chemicals,including caprolactams and cyclohexylamines,could be produced from lignin. 展开更多
关键词 Biomass conversion Heterogeneous catalysis LIGNIN Dual-atom catalyst Selective C-ocleavage
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MATHEMATICAL MODELING AND BIFURCATION ANALYSIS FOR A BIOLOGICAL MECHANISM OF CANCER DRUG RESISTANCE
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作者 包康博 梁桂珍 +1 位作者 田天海 张兴安 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1165-1188,共24页
Drug resistance is one of the most intractable issues in targeted therapy for cancer diseases.It has also been demonstrated to be related to cancer heterogeneity,which promotes the emergence of treatment-refractory ca... Drug resistance is one of the most intractable issues in targeted therapy for cancer diseases.It has also been demonstrated to be related to cancer heterogeneity,which promotes the emergence of treatment-refractory cancer cell populations.Focusing on how cancer cells develop resistance during the encounter with targeted drugs and the immune system,we propose a mathematical model for studying the dynamics of drug resistance in a conjoint heterogeneous tumor-immune setting.We analyze the local geometric properties of the equilibria of the model.Numerical simulations show that the selectively targeted removal of sensitive cancer cells may cause the initially heterogeneous population to become a more resistant population.Moreover,the decline of immune recruitment is a stronger determinant of cancer escape from immune surveillance or targeted therapy than the decay in immune predation strength.Sensitivity analysis of model parameters provides insight into the roles of the immune system combined with targeted therapy in determining treatment outcomes. 展开更多
关键词 mathematical model drug resistance cancer heterogeneity immune system targeted therapy
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Effects of individual heterogeneity on social contagions
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作者 年福忠 杨宇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期737-747,共11页
Despite having significant effects on social contagions,individual heterogeneity has frequently been overlooked in earlier studies.To better understand the complexity of social contagions,a non-Markovian model incorpo... Despite having significant effects on social contagions,individual heterogeneity has frequently been overlooked in earlier studies.To better understand the complexity of social contagions,a non-Markovian model incorporating heterogeneous social influence and adoption thresholds is introduced.For theoretical analysis,a generalized edge-based compartmental theory which considers the heterogeneities of social influence and adoption thresholds is developed.Focusing on the final adoption size,the critical propagation probability,and the phase transition type,social contagions for adoption thresholds that follow normal distributions with various standard deviations,follow various distributions,and correlate with degrees are investigated.When thresholds follow normal distributions,a larger standard deviation results in a larger final adoption size when the information propagation probability is relatively low.However,when the information propagation probability is relatively high,a larger standard deviation results in a smaller final adoption size.When thresholds follow various distributions,crossover phenomena in phase transition are observed when investigating the relationship of the final adoption size versus the average adoption threshold for some threshold distributions.When thresholds are correlated with degrees,similar crossover phenomena occur when investigating the relationship of the final adoption size versus the degree correlation index.Additionally,we find that increasing the heterogeneity of social influence suppresses the effects of adoption threshold heterogeneity on social contagions in three cases.Our theory predictions agree well with the simulation results. 展开更多
关键词 complex networks social contagions HETEROGENEITY phase transition
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Traffic Flow Prediction with Heterogeneous Spatiotemporal Data Based on a Hybrid Deep Learning Model Using Attention-Mechanism
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作者 Jing-Doo Wang Chayadi Oktomy Noto Susanto 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1711-1728,共18页
A significant obstacle in intelligent transportation systems(ITS)is the capacity to predict traffic flow.Recent advancements in deep neural networks have enabled the development of models to represent traffic flow acc... A significant obstacle in intelligent transportation systems(ITS)is the capacity to predict traffic flow.Recent advancements in deep neural networks have enabled the development of models to represent traffic flow accurately.However,accurately predicting traffic flow at the individual road level is extremely difficult due to the complex interplay of spatial and temporal factors.This paper proposes a technique for predicting short-term traffic flow data using an architecture that utilizes convolutional bidirectional long short-term memory(Conv-BiLSTM)with attention mechanisms.Prior studies neglected to include data pertaining to factors such as holidays,weather conditions,and vehicle types,which are interconnected and significantly impact the accuracy of forecast outcomes.In addition,this research incorporates recurring monthly periodic pattern data that significantly enhances the accuracy of forecast outcomes.The experimental findings demonstrate a performance improvement of 21.68%when incorporating the vehicle type feature. 展开更多
关键词 Traffic flow prediction sptiotemporal data heterogeneous data Conv-BiLSTM DATA-CENTRIC intra-data
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Effects of connected automated vehicle on stability and energy consumption of heterogeneous traffic flow system
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作者 申瑾 赵建东 +2 位作者 刘华清 姜锐 余智鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期291-301,共11页
With the development of intelligent and interconnected traffic system,a convergence of traffic stream is anticipated in the foreseeable future,where both connected automated vehicle(CAV)and human driven vehicle(HDV)wi... With the development of intelligent and interconnected traffic system,a convergence of traffic stream is anticipated in the foreseeable future,where both connected automated vehicle(CAV)and human driven vehicle(HDV)will coexist.In order to examine the effect of CAV on the overall stability and energy consumption of such a heterogeneous traffic system,we first take into account the interrelated perception of distance and speed by CAV to establish a macroscopic dynamic model through utilizing the full velocity difference(FVD)model.Subsequently,adopting the linear stability theory,we propose the linear stability condition for the model through using the small perturbation method,and the validity of the heterogeneous model is verified by comparing with the FVD model.Through nonlinear theoretical analysis,we further derive the KdV-Burgers equation,which captures the propagation characteristics of traffic density waves.Finally,by numerical simulation experiments through utilizing a macroscopic model of heterogeneous traffic flow,the effect of CAV permeability on the stability of density wave in heterogeneous traffic flow and the energy consumption of the traffic system is investigated.Subsequent analysis reveals emergent traffic phenomena.The experimental findings demonstrate that as CAV permeability increases,the ability to dampen the propagation of fluctuations in heterogeneous traffic flow gradually intensifies when giving system perturbation,leading to enhanced stability of the traffic system.Furthermore,higher initial traffic density renders the traffic system more susceptible to congestion,resulting in local clustering effect and stop-and-go traffic phenomenon.Remarkably,the total energy consumption of the heterogeneous traffic system exhibits a gradual decline with CAV permeability increasing.Further evidence has demonstrated the positive influence of CAV on heterogeneous traffic flow.This research contributes to providing theoretical guidance for future CAV applications,aiming to enhance urban road traffic efficiency and alleviate congestion. 展开更多
关键词 heterogeneous traffic flow CAV linear stability nonlinear stability energy consumption
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Ultra‑Efficient and Cost‑Effective Platinum Nanomembrane Electrocatalyst for Sustainable Hydrogen Production
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作者 Xiang Gao Shicheng Dai +8 位作者 Yun Teng Qing Wang Zhibo Zhang Ziyin Yang Minhyuk Park Hang Wang Zhe Jia Yunjiang Wang Yong Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期95-110,共16页
Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources.However,the widespread adoption of efficient electro... Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy sources.However,the widespread adoption of efficient electrocatalysts,such as platinum(Pt),has been hindered by their high cost.In this study,we developed an easy-to-implement method to create ultrathin Pt nanomembranes,which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal electrocatalysts.These Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field,a characteristic rarely seen in conventional crystals.This unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts,including Pt/C,Pt foils,and numerous Pt singleatom or single-cluster catalysts.Our research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production,potentially addressing the challenges posed by the climate crisis. 展开更多
关键词 PLATINUM Hydrogen evolution reaction Lattice distortion Heterogeneous strain
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Discreet investors exert greater influence on cooperation in the public goods game
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作者 康洪炜 金展瑶 +4 位作者 李明远 旺咩 孙兴平 沈勇 陈清毅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期170-178,共9页
This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,coo... This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,cooperators and discreet investors.Among these,defectors do not participate in investing,discreet investors make heterogeneous investments based on the investment behavior and cooperation value of their neighbors,and cooperators invest equally in each neighbor.In real life,heterogeneous investment is often accompanied by time or economic costs.The discreet investors in this paper pay a certain price to obtain their neighbors'investment behavior and cooperation value,which quantifies the time and economic costs of the heterogeneous investment process.The results of Monte Carlo simulation experiments in this study show that discreet investors can effectively resist the invasion of the defectors,form a stable cooperative group and expand the cooperative advantage in evolution.However,when discreet investors pay too high a price,they lose their strategic advantage.The results in this paper help us understand the role of heterogeneous investment in promoting and maintaining human social cooperation. 展开更多
关键词 public goods game heterogeneous investment discreet investors COOPERATION
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Global patterns and ecological drivers of taxonomic and phylogenetic endemism in angiosperm genera
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作者 Hong Qian Brent D.Mishler +1 位作者 Jian Zhang Shenhua Qian 《Plant Diversity》 SCIE CAS CSCD 2024年第2期149-157,共9页
Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here... Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation,extinction,and dispersal have influenced current distributions.Here,we investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world.We identify centers of paleo-endemism and neo-endemism of angiosperm genera,and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions,particularly in Asia and Australia.Different categories of phylogenetic endemism centers can be differentiated using current climate conditions.Current climate,historical climate change,and geographic variables together explained~80%of global variation in taxonomic and phylogenetic endemism,while 42-46%,1%,and 15%were independently explained by these three types of variables,respectively.Thus our findings show that past climate change,current climate,and geography act together in shaping endemism,which are consistent with the findings of previous studies that higher temperature and topographic heterogeneity promote endemism.Our study showed that many centers of phylogenetic endemism of angiosperms,including regions in Amazonia,Venezuela,and west-central tropical Africa that have not previously been identified as biodiversity hotspots,are missed by taxon-based measures of endemism,indicating the importance of including evolutionary history in biodiversity assessment. 展开更多
关键词 ANGIOSPERM Current climate ENDEMISM Historical climate change Topographic heterogeneity
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Individual dynamics and local heterogeneity provide a microscopic view of the epidemic spreading
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作者 朱友源 沈瑞哲 +1 位作者 董昊 王炜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期656-663,共8页
The COVID-19 pandemic has caused severe global disasters,highlighting the importance of understanding the details and trends of epidemic transmission in order to introduce efficient intervention measures.While the wid... The COVID-19 pandemic has caused severe global disasters,highlighting the importance of understanding the details and trends of epidemic transmission in order to introduce efficient intervention measures.While the widely used deterministic compartmental models have qualitatively presented continuous “analytical” insight and captured some transmission features,their treatment usually lacks spatiotemporal variation.Here,we propose a stochastic individual dynamical(SID)model to mimic the random and heterogeneous nature of epidemic propagation.The SID model provides a unifying framework for representing the spatiotemporal variations of epidemic development by tracking the movements of each individual.Using this model,we reproduce the infection curves for COVID-19 cases in different areas globally and find the local dynamics and heterogeneity at the individual level that affect the disease outbreak.The macroscopic trend of virus spreading is clearly illustrated from the microscopic perspective,enabling a quantitative assessment of different interventions.Seemingly,this model is also applicable to studying stochastic processes at the “meter scale”,e.g.,human society’s collective dynamics. 展开更多
关键词 Brownian motion epidemic spreading HETEROGENEITY
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Mitigating Lattice Distortion of High‑Voltage LiCoO_(2)via Core‑Shell Structure Induced by Cationic Heterogeneous Co‑Doping for Lithium‑Ion Batteries
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作者 Zezhou Lin Ke Fan +9 位作者 Tiancheng Liu Zhihang Xu Gao Chen Honglei Zhang Hao Li Xuyun Guo Xi Zhang Ye Zhu Peiyu Hou Haitao Huang 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期169-182,共14页
Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since ... Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries. 展开更多
关键词 Lithium-ion battery LiCoO_(2) Heterogeneous co-doping Core-shell structure High-voltage stability
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Effect of Modulus Heterogeneity on the Equilibrium Shape and Stress Field ofαPrecipitate in Ti-6Al-4V
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作者 Di Qiu Rongpei Shi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1017-1028,共12页
For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the interfaces.T... For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the interfaces.These stress fields depend on the inclusions’size,shape,and distribution and will respond instantly to the evolving microstructure.This study develops a phase-field model concerningmodulus heterogeneity.The effect of modulus heterogeneity on the growth process and equilibrium state of theαplate in Ti-6Al-4V during precipitation is evaluated.Theαprecipitate exhibits strong anisotropy in shape upon cooling due to the interplay of the elastic strain and interfacial energy.The calculated orientation of the habit plane using the homogeneous modulus ofαphase shows the smallest deviation fromthat of the habit plane observed in the experiment,compared to the case where the homogeneous modulus ofβphase is adopted.In addition,the equilibrium volume ofαphase within the systemusing homogeneousβmodulus exhibits the largest dependency on the applied stresses.The stress fields across theα/βinterface are further calculated under the assumption of modulus heterogeneity and compared to those using homogeneous modulus of eitherαorβphase.This study provides an essential theoretical basis for developing mechanics models concerning systems with heterogeneous structures. 展开更多
关键词 Elastic heterogeneity habit plane stress field TITANIUM phase-field simulation
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