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Rock strength weakening subject to principal stress rotation:Experimental and numerical investigations

Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3544-3557页

作者： Huandui Liu Guibin Wang Chunhe Yang Junyue Zhang Shiwan Chen State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Coal Mine Disaster Dynamics and Control College of Resources and Environmental SciencesChongqing UniversityChongqing400044China College of resources and environmental Engineering Guizhou UniversityGuiyang50025China

During the construction and operation of gas storage reservoirs,changes in the principal stress direction can induce fracture propagation under conditions of lower differential stress,potentially leading to failure in the surrounding ***,the weakening of strength due to pure stress rotation has not yet been *** on fracture mechanics,an enhanced Mohr-Coulomb strength criterion considering stress rotation is proposed and verified with experimental and numerical *** micro-damage state and the evolution of the rock under the pure stress-rotation condition are *** findings indicate that differential stress exceeding the crack initiation stress is a prerequisite for stress rotation to promote the development of rock *** the differential stress increases,stress rotation is more likely to induce rock damage,leading to a transition from brittle to plastic failure,characterized by wider fractures and a more complex fracture ***,a negative exponential relationship exists between the stress rotation angle required for rock failure and the differential *** feasibility of applying the enhanced criterion to practical engineering is discussed using monitoring data obtained from a mine-by *** study introduces new concepts for understanding the damage evolution of the surrounding rock under complex stress paths and offers a new theoretical basis for predicting the damage of gas storage reservoirs.

关键词： Principal stress rotation(PSR) Fracture mechanics Hollow cylinder torsional apparatus for rock (HCAR) Particle flow method Rock strength

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Time-first approach for land cover mapping using big Earth observation data time-series in a data cube-a case study from the Lake Geneva region(Switzerland)

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Big Earth Data 2024年第3期8卷 435-466页

作者： Gregory Giuliani Institute for environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland United Nations Environment Programme Division of Early Warning and AssessmentGenevaSwitzerland

Accurate,consistent,and high-resolution Land Use&Cover(LUC)information is fundamental for effectively monitoring landscape dynamics and better apprehending drivers,pressures,state,and impacts on land ***,the availability of such national products with high thematic accuracy is still limited and consequently researchers and policymakers are constrained to work with data that do not necessarily reflect on-the-ground realities impending to correctly capture details of landscape features as well as limiting the identification and quantification of drivers and rate of ***,we took advantage of the Switzerland’s official LUC statistical sampling survey and dense time-series of Sentinel-2 data,combining them with Machine and Deep Learning methods to produce an accurate and high spatial resolution land cover map over the Lake Geneva *** suggest that time-first approach is a valuable alternative to space-first approaches,accounting for the intra-annual variability of classes,hence improving classification *** demonstrate that Deep Learning methods outperform more traditional Machine Learning ones such as Random Forest,providing more accurate predictions with lower *** produced land cover map has a high accuracy,an improved spatial resolution,while at the same time preserving the statistical significance(*** proportion)of the official national *** work paves the way towards the objective to produce a yearly high resolution land cover map of Switzerland and potentially implement a continuous land change monitoring *** further work is required to properly address challenges such as the need for increased temporal resolution for LUC information or the quality of training samples.

关键词： Land cover Sentinel-2 timeseries SITS Arealstatistik

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Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains

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Plant Diversity 2024年第5期46卷 661-670页

作者： Ling-Yun Wu Shuang-Quan Huang Ze-Yu Tong Faculty of resources and environmental Science Hubei UniversityWuhan 430062China Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhan 430079China

Reproductive strategies of sexually dimorphic plants vary in response to the ***,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine *** answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern *** also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen *** pollen deposition was more variable in distylous species than in homostylous *** seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous *** findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

关键词： Biodiversity hotspot Elevation gradient Fagopyrum Stigmatic pollen load Temporal pattern

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Comparison of indicators for agricultural green development and the Sustainable Development Goals,and mapping the way forward

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 69-82页

作者： Jianjie ZHANG Xiangwen FAN Ling LIU Lin MA Zhaohai BAI Wenqi MA College of resources and environmental Sciences Hebei Agricultural UniversityBaoding 071001China College of resources and Environment Shanxi Agricultural UniversityTaiyuan 030031China Center for Agricultural resources Research Institute of Genetics and Development BiologyChinese Academy of SciencesShijiazhuang 050022China

While agricultural green development(AGD)is highly recognized and has become a national strategy in China,it is imperative to bridge the knowledge gaps between AGD and the UN Sustainable Development Goals(SDGs),and to evaluate the contribution of AGD to meeting the *** first aim of this study was to compare the AGD goals and indicators with those of the SDGs so as to identify their *** next aim was to examine the historical evolution of AGD indicators and analyze the gaps between the current status of various indicators and their *** factors were identified in China's transition toward *** findings reveal that the indicators of AGD align with those of the SDGs,but have greater specificity to the context in China and are more *** has been a significant increase per capita calorie and protein intakes in China,as well as a notable rise in agricultural output per unit of arable land and rural incomes from 1980 to the ***,these achievements have been accompanied by a high resource use and environmental pollution,highlighting the need for a more sustainable,environmentally responsible agriculture in China.

关键词： Agricultural green development sustainable development goals environmental sustainability indicator system optimization pathway

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Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu Song Yuan Chen Sheng-Bao Shi School of Petroleum Engineering and environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

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Resolving controversies surrounding carbon sinks from carbonate weathering

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Science China Earth Sciences 2024年第9期67卷 2705-2717页

作者： Xiaoyong BAI Sirui ZHANG Pete SMITH Chaojun LI Lian XIONG Chaochao DU Yingying XUE Zilin LI Mingkang LONG Minghui LI Xiaoyun ZHANG Shu YANG Qing LUO Xiaoqian SHEN State Key Laboratory of environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Institute of Biological and environmental Sciences University of AberdeenAberdeen AB243UUUK College of resources and environmental Engineering Guizhou UniversityGuiyang 550025China School of Geography and environmental Sciences Guizhou Normal UniversityGuiyang 550025China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

The importance of carbonate weathering carbon sinks(CCSs)is almost equal to that of vegetation photosynthesis in the global carbon ***,CCSs have become controversial in formulating carbon neutral policies to deal with global climate problems in various countries,since the carbonate dissolution is *** order to address these controversies,we reviewed recent advances in understanding CCSs and examined the outstanding controversies surrounding *** have analyzed the five controversies,revealing the existence of CCSs,quantifying their magnitude,clarifying their spatiotemporal pattern,and documenting how they have increased and how they evolved under the background of global *** addressing these five controversies,we help to bring clarity to the role of CCSs in the carbon cycle of global terrestrial ecosystems.

关键词： Carbon sink Carbonate weathering Carbon cycle Climate change Anthropogenic driver

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Cu-Zn isotope compositions of hydrothermal sediments from the southern Mid-Atlantic Ridge:implications to the sediment formation and mineral exploration

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Journal of Oceanology and Limnology 2024年第5期42卷 1470-1485页

作者： Baoju YANG Lianhua HE Chuanshun LI Qiannan HU Bingfu JIN Jihua LIU School of resources and environmental Engineering Ludong UniversityYantai 264025China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in *** and oxides in the samples were separated,and Cu and Zn isotope compositions were *** show that the ranges ofδ^(65)Cu values of the bulk sediments,sulfides,and oxides were 0.36‰-2.46‰,-0.21‰-1.10‰,and 0.68‰-1.52‰,***δ^(65)Cu values of sulfides in four samples(46II-14,46II-30,46III-06,and 46II-09)were relatively low(-0.21‰-0.50‰),corresponding to theδ^(65)Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge(n MAR),suggesting that the sulfides in the sediments were originated from collapsed dead chimney *** theδ^(65)Cu values of the other two samples(46III-02 and 46III-08)were relatively high(1.10‰-0.96‰),corresponding to theδ^(65)Cu values for active hydrothermal chimneys sulfides in n MAR,which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal *** of the high density of sulfide particles,they tended to settle near the hydrothermal vents ***,highδ^(65)Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal ***δ^(66)Zn values of hydrothermal sediments and sulfides ranged 0.11‰-0.43‰and 0.29‰-0.67‰,*** the four samples from the Xunmei hydrothermal field,a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio,showing that the greater the distance from the mineralized spot,the heavier the Zn isotope composition as seen in two samples(46II-30 and 46II-14)of the Xunmei-3 *** result aligned with the findings of Wilkinson et al.(2005)and Baumgartner et al.(2023),sugges

关键词： Cu-Zn isotope hydrothermal sediments mineral exploration southern Mid-Atlantic Ridge

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Electrochemistry and DFT study of galvanic interaction on the surface of monoclinic pyrrhotite(001)and galena(100)

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International Journal of Mining Science and Technology 2024年第8期34卷 1151-1162页

作者： Tingsheng Qiu Kaiwei Ding Huashan Yan Liu Yang Hao Wu Guanfei Zhao Xianhui Qiu College of Resource and environmental Engineering Jiangxi University of Science and TechnologyGanzhou 341000China Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral resources Ganzhou 341000China Jiangxi environmental Engineering Vocational College Ganzhou 341000China

The electrochemical interaction between galena and monoclinic pyrrhotite was investigated to examine its impact on the physical and chemical properties of the mineral *** investigation employed techniques such as electrochemistry,metal ion stripping,X-ray photoelectron spectroscopy,and quantum *** electrochemical test results demonstrate that the galena surface in the electro-couple system exhibits a lower electrostatic potential and higher electrochemical activity compared to the monoclinic pyrrhotite surface,rendering it more susceptible to oxidation *** pyrrhotite significantly amplifies the corrosion rate of the galena *** charge population calculations indicate that electrons are consistently transferred from galena to monoclinic pyrrhotite,with the number of electron transfers on the mineral surface increasing as the interaction distance *** analysis of state density revealed a shift in the surface state density of galena towards lower energy levels,resulting in decreased reactivity and increased difficulty for the reagent to adsorb onto the mineral ***,monoclinic pyrrhotite exhibited an opposite *** X-ray photoelectron spectroscopy(XPS)test results indicate that galvanic interaction leads to the formation of hydrophilic substances,PbS_(x)O_(y) and Pb(OH)_(2),on the surface of ***,the surface of monoclinic pyrrhotite not only adsorbs Pb^(2+)but also undergoes S^(0) formation,thereby augmenting its hydrophobic nature.

关键词： Electrochemistry Galvanic interaction Monoclinic pyrrhotite Galena Density functional theory

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Steam disinfection enhances bioaccessibility of metallic nanoparticles in nano-enabled silicone-rubber baby bottle teats,pacifiers,and teethers

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Journal of environmental Sciences 2024年第2期136卷 161-171页

作者： Yu Su BinWang Xin Tong Shuchuan Peng Sijin Liu Baoshan Xing Rong Ji State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China School of resources and environmental Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Stockbridge School of Agriculture University of MassachusettsAmherstMA 01003USA

Nano-enabled silicone-rubber articles for feeding or chewing could be a source of metallic nanoparticles(NPs)directly exposed to infants and young ***,the impact of steam disinfection on release of NPs and the related potential risks to children's health are ***,we investigated contents and form of Ag and Zn in 57 nano-enabled silicone-rubber baby bottle teats,pacifiers,and teethers of seven countries and examined the impacts of steam disinfection on in vitro bioaccessibility(IVBA)of Ag and Zn in the *** 89%articles had a mixture of Ag-and Zn-containing NPs and the teethers had relatively high Ag and Zn contents(up to 501 and 254μg/g,respectively).Steam disinfection caused rubber decomposition into micro(nano)plastics(0.54-15.7μm)and NP release from the interior of bulk rubber and micro-sized plastics,thus enhancing the IVBA of Ag and Zn by up to 5.5 *** findings provide insights into mechanisms for NP release by steam *** oral exposure risk assessment suggested low health concerns on individual metal release,our study points out the need to assess the potential health risks of child co-exposure to metallic NPs and micro(nano)plastics.

关键词： Silicone rubber Metallic nanoparticles Micro(nano)plastics Bioaccessibility Children's health

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Mechanistic study on 4,4'-sulfonylbis removal with CO_(2)/Ar gas-liquid DBD plasma

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Plasma Science and Technology 2024年第10期26卷 82-92页

作者： Guangjia WANG Shidong FANG Baoguo LIN Chengzhu ZHU Jie SHEN School of resources and environmental Engineering Hefei University of TechnologyHefei 230009People’s Republic of China Institute of Plasma Physics HFIPSChinese Academy of SciencesHefei 230031People’s Republic of China Anhui Kexin environmental Protection Co.Ltd. Hefei 230031People’s Republic of China

In this study,a single dielectric barrier discharge(DBD)coaxial reactor was used to degrade 4,4'-sulfonylbis(TBBPS)in water using greenhouse gas(CO_(2))and argon as the carrier *** investigation focused on CO_(2)conversion,reactive species formation,gas-liquid mass transfer mechanism,and degradation mechanism of TBBPS during the discharge plasma *** the decrease of CO_(2)/Ar ratio in the process of plasma discharge,the emission spectrum intensity of Ar,CO_(2)and excited reactive species was *** increase promoted collision and dissociation of CO_(2),resulting in a series of chemical reactions that improved the production of reactive species such as·OH,^(1)O_(2),H_(2)O_(2)and O_(3).These reactive species initiated a sequence of reactions with *** indicated that at a gas flow rate of 240 mL/min with a CO_(2)/Ar ratio of 1:5,both the highest CO_(2)conversion rate(17.76%)and TBBPS degradation rate(94.24%)were *** degradation mechanism was elucidated by determining types and contents of reactive species present in treatment liquid along with analysis of intermediate products using liquid chromatography-mass spectrometry *** research provides novel insights into carbon dioxide utilization and water pollution control through dielectric barrier discharge plasma technology.

关键词： dielectric barrier discharge carbon dioxide conversion 4 4'-sulfonylbis wastewater treatment

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