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Trace Element Mobility in Subducted Marble and Associated Eclogite:Constraints from UHP Rocks in the Shuanghe Area,Central-East China

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Journal of Earth Science 2024年第1期35卷 1-15页

作者： Xingao hou Zhiqiang Yu Shefa Chen Lei Liu Yilin Xiao Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring Ministry of EducationSchool of Geosciences and Info-PhysicsCentral South UniversityChangsha 410083China Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

In order to decipher element mobility in UHP meta-sedimentary rocks in the continental subduction zone,major and trace element compositions are investigated for a continuous profile from a representative UHP region in the Dabie *** the lithologic contact zone,contents of K,Ca,LREE,and LILE exhibit varying degrees of downward trends in both marble and eclogite toward the contact zone,indicating that marble and their associated eclogite can release a large amount of K,Ca,and a small number of LILEs and *** is the main Ti phase in both marble and *** rims around rutile can occasionally be seen in *** of Ti and HFSE exhibit a well-coupled relation among marble and eclogite,indicating that substantial Ti and HFSEs were migrated from eclogite to marble,in accord with the capacity of a melt *** and titanites in marble exhibit a relatively limited variation in Nb/Ta ratios(12.9-16.2),similar to those of titanites in eclogite(14.2-16.7),which demonstrates that rutiles and titanites in marble were sourced from eclogite because of short-distance migrations of Ti and *** to the P-T path and the temperature and pressure conditions of the peak metamorphism reported by previous studies,the eclogite associated with marble may not form supercritical fluids in the subduction zone because of the addition of carbonate minerals.

关键词： UHP metamorphism eclogite marble element migration fluid actions geochemistry

Phylogenetic study on Scenedesmacae with the description of a new genus Coccoidesmus ***.(Chlorophyceae,Chlorophyta)and chloroplast genome analyses

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Journal of Oceanology and Limnology 2024年第4期42卷 1272-1285页

作者： Qinghua WANG Ying hou Yanhui LI Ying SHI Guoxiang LIU College of Biological Sciences and Technology Taiyuan Normal UniversityJinzhong 030619China Shanxi Vocational University of Engineering Science and Technology Jinzhong 030619China Key Laboratory of Algal Biology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China

Members of the family Scenedesmaceae are some of the most common algal taxa in inland ecosystems,and they are widely distributed in freshwaters,aerial,and sub-aerial *** the continuous updating of methods,the classic morphological taxonomy of this family needs to be *** recent years,many genera of Scenedesmaceae have been established via the use of molecular *** phylogenetic relationships within Scenedesmaceae were analyzed using different molecular markers and morphological data,and the new freshwater genus Coccoidesmus Wang,hou et Liu *** *** new species in this genus were also *** analysis based on tufA genes revealed that the new genus formed an independent clade closely related to ***,these two genera are characterized by significant morphological differences in colony arrangement and cell *** chloroplast genome of the type species was assembled and annotated,and analyses of genome structure and sequences were *** genome data could help clarify the phylogenetic relationships within this family.

关键词： phylogenetic Scenedesmaceae Coccoidesmus morphology chloroplast genome

Temperature is a cryptic factor shaping the geographical pattern of genetic variation in Ceratophyllum demersum across a subtropical freshwater lake

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Plant Diversity 2024年第5期46卷 630-639页

作者： Yixian Li Xuyao Zhao Manli Xia Xinzeng Wei Hongwei hou The State Key Laboratory of Freshwater Ecology and Biotechnology The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of SciencesInstitute of HydrobiologyChinese Academy of SciencesWuhan 430072HubeiChina University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074HubeiChina

Macrophyte habitats exhibit remarkable heterogeneity,encompassing the spatial variation of abiotic and biotic components such as changes in water conditions and weather as well as anthropogenic *** factors are thought to be important drivers shaping the genetic and epigenetic variation of aquatic ***,the links among genetic diversity,epigenetic variation,and environmental variables remain largely unclear,especially for clonal aquatic ***,we performed population genetic and epigenetic analyses in conjunction with habitat discrimination to elucidate the environmental factors driving intraspecies genetic and epigenetic variation in hornwort(Ceratophyllum demersum)in a subtropical *** factors were highly correlated with the genetic and epigenetic variation of ***,with temperature being a key driver of the genetic *** temperature was detected to be correlated with greater genetic and epigenetic *** and epigenetic variation were positively driven by water temperature,but were negatively affected by ambient air *** findings indicate that the genetic and epigenetic variation of this clonal aquatic herb is not related to the geographic feature but is instead driven by environmental conditions,and demonstrate the effects of temperature on local genetic and epigenetic variation in aquatic systems.

关键词： Genetic diversity Epigenetic variation Temperature Macrophyte Restoration

Investigation on the Deformation and Failure Patterns of Loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an,China

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Journal of Earth Science 2024年第1期35卷 235-247页

作者： Lina Ma Shengwen Qi Songfeng Guo Qiangbing Huang Xiaokun hou Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Department of Geological Engineering Chang'an UniversityXi'an 710054China

The large-scale implementation of the Gully Stabilization and Land Reclamation(GSLR)project induces various failures of loess slopes due to excavation in Yan'an,***,the deformation and failure behavior of these excavated loess slopes have not been fully *** this study,field investigation was undertaken for analyzing the distributions and failure features of excavation-induced loess slope *** is found that plastic failure mainly occurs in Q_(3) loess layers and brittle failure in Q_(2).To understand the underlying failure mechanism,a series of triaxial shear tests were conducted on intact Q_(3) and Q_(2) loess samples that with different water contents,namely natural water content(natural),dry side of the natural value(drying 5%),and wet side(wetting 5%).The characteristics of stress-strain curves and failure modes of the samples were *** show that the stress-strain curves of Q_(2) samples are dominated by strain-softening characteristics,while Q_(3) samples mainly exhibit strain-harden features except in the drying ***,shear failures of Q_(3) specimens are mainly caused by shear crack planes(single,X or V-shaped).For Q_(2) loess,the dominance of tensile cracks is observed on the surface of damaged *** disclose the different failure modes of excavated slopes located in different strata,that is,the arc sliding failure of Q_(3) loess slopes and the stepped tensile failure of Q_(2) loess slopes,and are helpful in the design and management of the ongoing GSLR projects in the Loess Plateau.

关键词： loess slope slope stability failure patterns deformation

Ecological-Based Mining:A Coal-Water-Thermal Collaborative Paradigm in Ecologically Fragile Areas in Western China

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Engineering 2024年第7期38卷 209-222页

作者： Xiaoxiu Liu Yifan Zeng Qiang Wu Shihao Meng Jiyue Liang Zhuping hou National Engineering Research Center of Coal Mine Water Hazard Controlling China University of Mining and TechnologyBeijing 100083China College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083China University of Mining and Technology(Beijing)Inner Mongolia Research Institute Ordos 017000China

A substantial reduction in groundwater level,exacerbated by coal mining activities,is intensifying water scarcity in western China’s ecologically fragile coal mining ***’s national strategic goal of achieving a carbon peak and carbon neutrality has made eco-friendly mining that prioritizes the protection and efficient use of water resources *** on the resource characteristics of mine water and heat hazards,an intensive coal-water-thermal collaborative co-mining paradigm for the duration of the mining process is *** integrated system for the production,supply,and storage of mining companion resources is achieved through technologies such as roof water inrush prevention and control,hydrothermal quality improvement,and deep-injection geological *** active preventive and control system achieved by adjusting the mining technology and a passive system centered on multiobjective drainage and grouting treatment are suggested,in accordance with the original geological characteristics and dynamic process of water *** implementing advanced multi-objective drainage,specifically designed to address the“skylight-type”water inrush mode in the Yulin mining area of Shaanxi Province,a substantial reduction of 50%in water drillings and inflow was achieved,leading to stabilized water conditions that effectively ensure subsequent safe coal *** integrated-energy complementary model that incorporates the clean production concept of heat utilization is also *** findings indicate a potential saving of 8419 t of standard coal by using water and air heat as an alternative heating source for the Xiaojihan coalmine,resulting in an impressive energy conservation of 50.2%and a notable 24.2%reduction in carbon *** ultra-deep sustained water injection of 100 m^(3)·h^(-1)in a single well would not rupture the formation or cause water leakage,and 7.87×10^(5)t of mine water could be effectively stored in the Liujiagou Formation,presenti

关键词： Dual carbon targets Coal-water-thermal co-mining Ecologically fragile areas Mine-water control Resource utilization

Effect of Post-weld Heat Treatment on the Microstructure and Mechanical Properties of 2.25Cr-1Mo-0.25V Ultra-Thick Steel Plate

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1104-1114页

作者： Yanyang Wu Zongye Ding Wenquan Lu Jingchao hou Qiaodan Hu Jianguo Li Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai200444China School of Mechatronic Engineering and Automation Foshan UniversityFoshan528225GuangdongChina WuYang Iron and Steel Wugang450000HenanChina

Ensuring the homogeneous and excellent mechanical properties of 2.25Cr-1Mo-0.25V ultra-thick steel plate is the key to the production of hydrogenation reactor ***,it is required to understand the heterogeneity of microstructures and properties of ultra-thick plate after heat *** this work,the effect of post-weld heat treatment(PWHT)on the strength,plasticity,toughness and microstructures of the 193-mm-thick steel plate was investigated,and the formation mechanism of heterogeneity was *** PWHT decreased the room-and high-temperature yield strength(YS)and ultimate tensile strength(UTS)of the steel plate after normalizing and tempering(NT),while the room-and high-temperature YS and UTS decreased from the surface to the center of 193-mm-thick steel *** was attributed to the enhanced decomposition of martensite-austenite(M-A)constituents and coarsening of grains and precipitated carbides.

关键词： Cr-Mo steel Ultra-thick steel plate Microstructure Mechanical properties Heterogeneity

Adsorption of trichlorphon on phyllosilicate minerals:Effect of low-molecular-weight organic acids

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Pedosphere 2024年第1期34卷 78-87页

作者： Hongfeng CHEN Zhouyang HE Mingxia hou Cilai TANG Yonghong WU College of Hydraulic&Environmental Engineering China Three Gorges UniversityYichang 443002China Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region China Three Gorges UniversityYichang 443002China State Key Laboratory of Soi and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The use of trichlorphon in large quantities causes a large number of organic pollutants to enter water, sediments, and soils. Phyllosilicate minerals are considered effective adsorbents for organic pollutants. However, the adsorption behavior of organic pollutants on soil minerals affected by low-molecular-weight organic acids(LMWOAs) is not fully understood. In this study, the effect of LMWOAs on the adsorption behavior of trichlorphon on phyllosilicate minerals was investigated using a combination of adsorption measurements and molecular spectroscopic techniques(attenuated total reflection-Fourier transform infrared spectroscopy(ATR-FTIR) and X-ray photoelectron spectroscopy(XPS)). The adsorption of trichlorphon onto kaolinite(KAO) and montmorillonite(MON) was suppressed by increasing pH, indicating that electrostatic interaction played a key role in adsorption, especially at low pH. In the presence of citric acid(CA), there was an obvious promotion of trichlorphon adsorption on KAO and MON. In the presence of oxalic acid(OA), the adsorption of trichlorphon on KAO was promoted, whereas the adsorption on MON was inhibited, especially at pH 4.0. The presence of CA and OA increased the adsorption by increasing the exposure of hydrophobic sites of KAO and MON. The results from ATR-FTIR and XPS also indicated that the hydrophobic Si–O sites of phyllosilicate minerals were the preferred adsorption sites for trichlorphon in the presence of CA and OA, probably driven by the hydrophobic effect. However, the weak effect of OA on MON caused an increase in the electrostatic repulsion between MON and trichlorphon molecules, thus inhibiting adsorption. This study is significant for a deeper understanding of self-purification of soil and sediment systems in the presence of organic pollutants.

关键词： adsorption behavior citric acid hydrophobic effect organic pesticide organic pollutant organochlorine oxalic acid

A global model for evaluating discharge characteristics and performance of hollow cathodes

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Chinese Journal of Aeronautics 2024年第9期37卷 72-84页

作者： Feng TIAN Long MIAO Qimeng XIA Zhiwen WU Ningfei WANG Xiao hou School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China

Hollow cathode,with the highest plasma density,current density,and temperature,becomes one of the most important components in the electro-thruster *** the electric-propulsion thruster performance is directly related to the ionization rate,reliability,and lifetime of the hollow cathode,this paper develops a global model to study the effects of discharge current,gas flow rate,and gas species on the discharge characteristics in the insert and orifice regions of the hollow *** emitter wall temperatures of hollow cathodes predicted by the global model are compared with experimental results from NSTAR thruster neutralization cathodes,confirming the model's *** influence of hollow cathode emitter material and structure sizes on the plasma parameters in the internal regions was also *** simulation results show that there is an optimal matching relationship between the discharge current and gas flow rate to guarantee the maximum ionization *** optimal working region for the hollow cathode has been deter-mined under different energetic,regime and structural *** global model established in this paper can quickly determine the key structure and operating parameters of hollow cathode at the design stage,and provide the theoretical basis for hollow cathode design and development.

关键词： Hollow cathode Global model Electric propulsion Discharge characteristics Optimal matching relationship

Parameter Estimation of a Valve-Controlled Cylinder System Model Based on Bench Test and Operating Data Fusion

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 247-263页

作者： Deying Su Shaojie Wang Haojing Lin Xiaosong Xia Yubing Xu Liang hou Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361102China Xuzhou XCMG Excavation Machinery Co. LtdXuzhou 221000China

The accurate estimation of parameters is the premise for establishing a high-fidelity simulation model of a valve-controlled cylinder *** test data are easily obtained,but it is challenging to emulate actual loads in the research on parameter estimation of valve-controlled cylinder *** the actual load information contained in the operating data of the control valve,its acquisition remains *** paper proposes a method that fuses bench test and operating data for parameter estimation to address the aforementioned *** proposed method is based on Bayesian theory,and its core is a pool fusion of prior information from bench test and operating ***,a system model is established,and the parameters in the model are ***,the bench and operating data of the system are ***,the model parameters and weight coefficients are estimated using the data fusion ***,the estimated effects of the data fusion method,Bayesian method,and particle swarm optimisation(PSO)algorithm on system model parameters are *** research shows that the weight coefficient represents the contribution of different prior information to the parameter estimation *** effect of parameter estimation based on the data fusion method is better than that of the Bayesian method and the PSO *** load complexity leads to a decrease in model accuracy,highlighting the crucial role of the data fusion method in parameter estimation studies.

关键词： Valve-controlled cylinder system Parameter estimation The Bayesian theory Data fusion method Weight coefficients