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Mesoscale Mechanical Properties and Influencing Factors of Concrete under Uniaxial Tension

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1156-1168页

作者： CHEN Tao LI Kungang XIAO Shiyun state key laboratory of coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Monte Carlo simulations were carried out to generate a mesoscale model of concrete with randomly packed aggregates with different shapes and *** mechanical properties of concrete specimens under uniaxial tensile loads were studied using statistical *** results indicated that the entire process of damage and failure of specimens exhibited mainly two failure types:fracture patternsⅠandⅡ.Furthermore,the influences of the aggregate content ratio,aggregate shape,aggregate size,interfacial transition zone(ITZ)strength,and porosity ratio on the concrete specimens were *** numerical simulation results showed that the elastic modulus of the concrete specimens increased approximately linearly with the aggregate volume ratio but decreased linearly with the porosity and was not affected by the ITZ *** tensile strength decreased with the increases in the aggregate content and porosity of the sample,but increased linearly with the ITZ *** addition,the aggregate shape led to a difference in the tensile strength of the concrete.

关键词： concrete mechanical behavior aggregate interfacial transition zone pore

Global Dynamic Responses and Progressive Failure of Submerged Floating Tunnel Under Cable Breakage Conditions

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China Ocean Engineering 2024年第4期38卷 676-688页

作者： ZHOU Xiang-bo QIAO Dong-sheng WANG Ming TANG Guo-qiang LU Lin OU Jinping state key laboratory of coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise *** sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducing a transient heave response within the structure along with a transient increase in cable tension experienced by adjacent *** more severe cases,this may even lead to a progressive failure culminating in the global destruction of the *** study used ANSYS/AQWA to establish a numerical model of the entire length SFT for the hydrodynamic response analysis,and conducted a coupled calculation of the dynamic responses of the SFT-mooring line model based on Orca Flex to study the global dynamic responses of the SFT at the moment of cable breakage and the redistribution of cable internal *** most unfavorable position for SFT cable breakage was identified,the influence mechanism of cable breakage at different positions on the global dynamic response was revealed,and the progressive chain failure pattern caused by localized cable breakage are also clarified.

关键词： submerged floating tunnel cable breakage global dynamic responses progressive failure

Insight into the microbial community of denitrification process using different solid carbon sources: Not only bacteria

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Journal of Environmental Sciences 2024年第10期144卷 87-99页

作者： Congyu Li Yu Ling Yanjie Zhang Haiyan Wang Huan Wang Guokai Yan Weiyang Dong Yang Chang Liang Duan state key laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China College of Environmental Science and Engineering Tongji UniversityShanghai 200092China College of Water Sciences Beijing Normal UniversityBeijing 100875China research Center of Environmental Pollution Control Technology Chinese Research Academy of Environmental ScienceBeijing 100012China state Environmental Protection key laboratory of estuarine and coastal Environment Chinese Research Academy of Environmental SciencesBeijing 100012China

There is a lack of understanding about the bacterial,fungal and archaeal communities’composition of solid-phase denitrification(SPD)*** investigated four SPD systems with different carbon sources by analyzing microbial gene sequences based on operational taxonomic unit(OTU)and amplicon sequence variant(ASV).The results showed that the corncob-polyvinyl alcohol sodium alginate-polycaprolactone(CPSP,0.86±0.04 mg NO_(3)^(−)-N/(g·day))and corncob(0.85±0.06 mg NO_(3)^(−)-N/(g·day))had better denitrification efficiency than polycaprolactone(PCL,0.29±0.11 mg NO_(3)^(−)-N/(g·day))and polyvinyl alcoholsodium alginate(PVA-SA,0.24±0.07 mg NO_(3)^(−)-N/(g·day)).The bacterial,fungal and archaeal microbial composition was significantly different among carbon source types such as Proteobacteria in PCL(OTU:83.72%,ASV:82.49%)and Rozellomycota in PVA-SA(OTU:71.99%,ASV:81.30%).ASV methods can read more microbial units than that of OTU and exhibit higher alpha diversity and classify some species that had not been identified by OTU such as Nanoarchaeota phylum,unclassified_f_Xanthobacteraceae genus,etc.,indicating ASV may be more conducive to understand SPD microbial *** co-occurring network showed some correlation between the bacteria fungi and archaea species,indicating different species may collaborate in SPD *** KEGG function prediction results were obtained in two bioinformatic methods generally and some fungi and archaea functions should not be ignored in SPD *** results may be beneficial for understanding microbial communities in SPD systems.

关键词： Solid-phase denitrification Solid carbon source Microbial community ASV analysis OTU analysis

Total-factor energy efficiency of ten major global energy-consuming countries

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Journal of Environmental Sciences 2024年第3期137卷 41-52页

作者： Xuan Wang Yonglong Lu Chunci Chen Xiaojie Yi Haotian Cui state key laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China state key laboratory of Marine Environmental Science and key laboratory of the Ministry of Education for coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityFujian 361102China University of Chinese Academy of Sciences Beijing 100049China

Improving energy efficiency is regarded as a key path to tackling global warming and achieving the Sustainable Development Goals(SDGs).In 2020,the energy consumption of the world's ten major energy-consuming countries accounted for 66.8%of the global *** paper applied data envelopment analysis(DEA)to calculate these ten major energyconsuming countries'total-factor energy efficiency(TFEE)at national and sectoral levels from 2001-2020,and explored the infuencing factors of total-factor energy efficiency with the Tobit regression *** results showed significant difference in the ten countries'energy *** United states and Germany topped the list for total-factor energy efficiency,while China and India were at the ***,the energy efficiency of the industrial subsector has increased significantly over the past two decades,while that of the other subsectors has been relatively *** industrial structure upgrading,per capita GDP,energy consumption structure,and foreign direct investment had significant impacts on energy efficiency with national *** consumption structure and GDP per capita were determinative factors of energy efficiency.

关键词： Total-factor energy efficiency SBM-UN model Major energy-consuming country Carbon emission reduction

Equivalent linear model for seismic damage evaluation of single-degree-of-freedom systems representing reinforced concrete structures considering cyclic degradation behavior

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 637-648页

作者： Lulu Yan Ding-Hao Yu research Center for Geotechnical and Structural Engineering Technology of Liaoning Province Dalian UniversityDalian116622China state key laboratory of coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

In this study,a novel equivalent damping ratio model that is suitable for reinforced concrete(RC)structures considering cyclic degradation behavior is developed,and a new equivalent linearization analysis method for implementing the proposed equivalent damping ratio model for use in seismic damage evaluation is *** this end,Ibarra’s peak-oriented model,which incorporates an energy-based degradation rule,is selected for representing hysteretic behavior of RC structure,and the optimized equivalent damping for predicting the maximum displacement response is presented by using the empirical method,in which the effect of cyclic degradation is ***,the relationship between the hysteretic energy dissipation of the inelastic system and the elastic strain energy of the equivalent linear system is established so that the proposed equivalent linear system can be directly integrated with the Park-Ang seismic model to implement seismic damage *** to the simplicity of the equivalent linearization method,the proposed method provides an efficient and reliable way of obtaining comprehensive insight into the seismic performance of RC *** verification demonstrates the validity of the proposed method.

关键词： degrading system equivalent linear system equivalent damping seismic damage RC structures

Contemporary Asymmetric Genetic Introgression Between Two Pelophylax Species in Shanghai

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Asian Herpetological research 2024年第1期15卷 1-11页

作者： Xu WEI Wenli LIU Gang WANG Rui MA Meiling HUANG Jiaxin ZHENG Tingwei DONG Changqing YUAN Shunqi BO Xiao YUAN Ben LI Shuo MA Qu YUE Youzhong DING Zhenghuan WANG School of Life Sciences East China Normal UniversityShanghai 200241China Shanghai Landscaping and City Appearance Administrative Bureau Shanghai 200041China state key laboratory of estuarine and coastal research East China Normal UniversityShanghai 200241China Shanghai key Lab for Urban Ecological Processes and Eco-Restoration East China Normal UniversityShanghai 200241China Yangtze Delta estuarine Wetland Ecosystem Observation and research Station Ministry of Education&Shanghai Science and Technology CommitteeShanghai 202162China

Human disturbances are considered to break reproduction barriers among *** increases in hybridization events have been reported among a large number of taxonomic groups in anthropogenic environments,providing novel insights into species evolution mechanisms and conservation management in the *** Eastern Golden Frog(Pelophylax plancyi)and BlackSpotted Frog(***)are two sympatric anuran species with a long history of mitochondrial genome introgression in highly urbanized continental East ***,there is only limited understanding of the pattern of their contemporary hybridization and factors influencing their interspecific relationship under anthropogenic ***,interspecific hybridization between *** and *** at the population level was investigated in *** except two haplotypes obtained from both species in Shanghai were mixed together,and located in the introgression clade,implying multiple ancient mitochondrial introgression events occurred in the populations of our study *** genetic introgression was detected by microsatellite markers,with 0.7%of *** and 14.6%of *** identified as contemporary admixed *** with the trend of population density,higher genetic diversity of neutral microsatellite loci was found in the more abundant ***;however,variation in mitochondrial(Cyt-b)and nuclear(POMC)genes was higher in relatively rare *** population density of *** and number of water patches within local habitats were significantly positively correlated with both occurrences and proportions of admixed individuals in the populations of *** and *** the prevalent transformation of habitats in urbanized areas,these results imply that a high population density in isolated artificially altered habitats is likely to increase interspecific ***,population monitoring and improveme

关键词： anthropogenic disturbances interspecific hybridization Pelophylax species abundance urban landscape urbanization

Taxonomy of Two New Peritrich Ciliates(Protozoa:Ciliophora)from Inland Saltwaters of China

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Journal of Ocean University of China 2024年第3期23卷 811-821页

作者： YU Ying ZHANG Yong LIANG Ziyao LI Jiqiu LIN Xiaofeng key laboratory of Ministry of Education for coastal and Wetland Ecosystems Fujian Provincial Key Laboratory of Coastal Ecology and Environmental StudiesCollege of the Environment and EcologyXiamen UniversityXiamen 361102China School of Life Science South China Normal UniversityGuangzhou 510631China state key laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China

The inland saltwater lakes harbor exceptional ***,two new species of solitary sessile peritrich ciliates were isolated from Qinghai Lake,the largest inland saltwater lake in *** morphology,ciliature,silverline system,and molecular phylogeny were investigated based on live observation,silver staining,and analysis of the small subunit ribosomal DNA(SSU rDNA).Vorticella paraglobosa *** characterized mainly by its obconical or elongate bell-shaped zooid,C-shaped macronucleus,single ventrally located contractile vacuole,two-rowed infundibular polykinety 3,and 28-38 silverlines between peristome and aboral tro-chal band and 10-15 between aboral trochal band and *** cotyliformis *** from its congeners mainly by its double-layered peristomial lip,cup-shaped zooid,J-shaped macronucleus,single ventrally positioned contractile vacuole,three-rowed infundibular polykinety 3,and 70-85 silverlines between peristome and aboral trochal band and 21-25 between aboral trochal band and *** SSU rDNA sequences of the two new species were obtained,and the subsequent molecular phylogenetic analysis supported their taxonomic classification.

关键词： molecular phylogeny morphology new species Qinghai Lake taxonomy

Salinity Acclimation Induces Reduced Energy Metabolism,Osmotic Pressure Regulation and Transcriptional Reprogramming in Hypotrichida Ciliate Gastrostyla setifera

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Journal of Ocean University of China 2024年第2期23卷 539-549页

作者： JI Xin BI Luping ZOU Songbao LI Wenlu JI Daode ZHANG Qianqian School of Ocean Yantai UniversityYantai 264005China key laboratory of coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Zhejiang Institute of Freshwater Fisheries Huzhou 313001China Muping coastal Environment research Station Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264117China

coastal and estuarine protists are frequently exposed to salinity *** the tolerance and stress responses of microalgae to salinity have been extensively studied,there have been scarce studies on the physiological response of heterotrophic protists to salinity *** this study,we investigated the physiological response of the heterotrophic ciliate Gastrostyla setifera to a salinity of 3,via a transcriptomic *** first transcriptome of genus Gastrostyla was obtained utilizing a group of manually isolated ciliate individuals(cells)and RNA-seq *** completeness of the transcriptome was *** expressed gene(DEG)analysis was performed among the transcriptomes of *** acclimated in saline water(salinity 3)and those cultured in fresh *** results demonstrated a significant alternation in gene transcription,in which the ciliate exhibits a transcripttomic acclimation in responding salinity *** up-regulated DEGs were enriched in the pathways of cytoskeleton proteins,membrane trafficking,protein kinases and protein *** may represent enhanced functions of ion transport,stress response and cell *** involved in energy metabolism and biosynthesis were markedly down-regulated,reflecting decreased cell ***,we detected significantly down-regulated genes involved in several pathways of amino acid catabolism,which may lead to accumulation of amino acids in the ciliate *** acid could act as compatible solutes in the cytoplasm to maintain the osmotic balance in saline ***,this work is an initial exploration to the molecular basis of the heterotrophic protist responding to salinity *** result sheds light on the mechanisms of enhancement of cell protection,reduction of cell activity,and osmotic pressure regulation in ciliates acclimated to salinity.

关键词： salinity stress heterotrophic protist ciliate Gastrostyla setifera transcriptome differentially expressed gene

Underestimated activity-based microplastic intake under scenariospecific exposures

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Environmental Science and Ecotechnology 2024年第2期18卷 124-136页

作者： Kai Liu Qingqing Li Anthony LAndrady Xiaohui Wang Yinan He Daoji Li state key laboratory of estuarine and coastal research East China Normal University500 Dongchuan RoadShanghai200062China Department of Chemical and Biomolecular Engineering North Carolina State UniversityRaleighNC27695USA Plastic Marine Debris research Center East China Normal University500 Dongchuan RoadShanghai200241China Regional Training and research Center on Plastic Marine Debris and Microplastics IOC-UNESCO500 Dongchuan RoadShanghai200241China

Despite increasing alarms over the health impacts of microplastics(MPs)due to their detection in human organs and feces,precise exposure evaluations remain *** comprehend their risks,there is a distinct need to prioritize quantitive estimates in MP exposome,particularly at the environmentallyrealistic *** we used a method rooted in real-world MP measurements and activity patterns to determine the daily intake of MPs through inhalation and from ground dust/soil *** found that nearly 80%of this intake comes from residential sectors,with activity intensity and behavioral types significantly affecting the human MP *** data showed a peak in MP exposure for those aged *** compared to dietary MP intake sources like seafood,salt,and water,we identified a previously underestimated exposure from inhalation and dust/soil ingestion,emphasizing the need for more realistic evaluations that incorporate activity *** discovery raises questions about the accuracy of past studies and underscores MP's potential health ***,our time-based simulations revealed increased MP intake during the COVID-19 lockdown due to more surface dust ingestion,shedding light on how global health crises may inadvertently elevate MP exposure risks.

关键词： Microplastics Activity factors Inhalation and ingestion Simulation Exposure estimate