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A comparative review of magnesium isotope analysis methods for emerging geological applications: Double-spike vs. standard-sample-bracketing

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Science China Earth Sciences 2025年第04期68卷 1213-1222页

作者： Yi-Bo ZHAO Wen-Ning LU Jian-Bing XU Ming-Xing LING National key laboratory of Uranium Resource Exploration-Mining and nuclear Remote Sensing East China University of Technology state key laboratory of nuclear resources and environment East China University of Technology School of Earth Sciences East China University of Technology

Given the significant isotopic information in nature, magnesium(Mg) isotopes have played a pivotal role in elucidating the underlying mechanisms of environmental and geological processes. Along with the advancement of multicollector inductively coupled plasma mass spectrometry(MC-ICP-MS), the application of the standard-sample-bracketing(SSB) method, especially the recently developed double-spike(DS) method in Mg isotopes, has significantly enhanced precision to levels as low as ±0.03‰(2SD). This review primarily focuses on the comparative analysis of the above two methods, with special attention given to the DS method and its application in investigating intricate lithospheric processes with subtle Mg isotope fractionations. We first introduce the development of Mg isotopic analysis, followed by a detailed description of the basic principles of the SSB and DS methods. Subsequently, a comparative discussion of these two approaches is presented to assist researchers in choosing the preferred strategy for specific natural samples. Furthermore, we carefully discuss the more precise scales of equilibrium inter-mineral Mg isotopic fractionations through the DS method, emphasizing that with improved precision, a broader range of applications may emerge. This review ends with our insights and perspectives on this compelling topic, aiming to provide guidelines for advancing Mg isotopic analysis and inspiring researchers to explore various geo-environmental phenomena.

关键词： Mg isotopes Analysis methods Standard-sample-bracketing Double-spike Geological applications

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Synthesis of Ce/BiFeO3 composites and activation of persulfate for pharmaceutical wastewater degradation

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Journal of Rare Earths 2025年第3期43卷 462-469页

作者： Yanting Zuo Shi Cheng Ziwen Guo Haolin Liu Huaicheng Zhang Ji Wu Ziwu Fan Wentao Li Aimin Li key laboratory of Taihu Basin Water resources Management Ministry of Water ResourcesNanjing Hydraulic Research Institute School of Urban Construction Changzhou University School of resources and environmental Engineering Jiangsu University of Technology state key laboratory of Pollution Control and resources Reuse School of the EnvironmentNanjing University School of environment and Safety Engineering Nanjing Polytechnic Institute

Sulfamethoxazole（SMZ） is a prevalent and recalcitrant micropollutant in water,posing a significant threat to both aquatic organisms and human ***,investigating the removal of SMZ is of critical *** order to investigate the effect of rare earth metal doping on the performance of activated persulfate oxidative degradation of SMZ,BiFeO3with different Ce doping amounts was successfully prepared by a hydrothermal ***,it was characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,scanning transmission electro n microscopy（STEM） and Brunauer-Emmett-Teller（BET）*** performance of porous Ce/BiFeO3in the catalytic activation of persulfate（PMS） for the degradation of SMZ in water was investigated using SMZ solution as a simulated *** impact of Ce doping rate,catalyst dosage,temperature variations,common anions,natural organic matter,and PMS concentration on SMZ removal was systematically *** characterization results show that the octahedral rhombic structure of Ce can be observed on the surface of this doped catalyst,and Ce doping does not change the crystalline shape of Ce/*** specific surface area of the doped catalyst increases,accompanied by an enlargement of pore size,thereby enhancing the catalyst's adsorption capacity and resistance to contamination by *** the optimal conditions of 25℃,SMZ concentration of 20 mg/L,0.8 g/L PMS and 0.3 g/L 0.05Ce/BiFeO3catalyst,the removal rate of SMZ reaches approximately 95% within35 min of reaction *** after five cycles of reuse,the degradation rate of SMZ remains above 88%,demonstrating the catalyst's good stability and *** experiments show that SO4·-,·OH,1O2and O2·-are involved in the catalytic degradation process,with1O2playing a dominant role.

关键词： Ce/BiFeO3 Persulfate Rare earths Sulfamethoxazole Sulfate radicals

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The machine learning implementation and theoretical foundations of intelligent control of accelerator particle beams

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 199-200页

作者： XueQing Yan state key laboratory of nuclear Physics and Technology Peking UniversityBeijing 100871China

The intelligent control of accelerator particle beams,achieved through machine learning,offers a new opportunity for the design and regulation of high-power,high-intensity *** recent years,this technology has been applied in several practical *** instance,the DeepMind team successfully used reinforcement learning to control the plasma in a Tokamak device with 19 control magnets[1].

关键词： particle instance accelerator

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Analysis of planform migration characteristics and lag effects in meandering rivers using remote sensing image interpretation

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Science China Earth Sciences 2025年第3期68卷 824-835页

作者： Jizhe HU Junqiang XIA Shanshan DENG state key laboratory of Water resources Engineering and Management Wuhan UniversityWuhan 430072China

Meandering rivers of various scales are found globally and exhibit a high degree of regularity in their evolutionary processes. This study utilized remote sensing interpretation techniques to extract and analyze the planform migration characteristics of meandering rivers. Specifically, remote sensing images of three meandering rivers—the Black and White Rivers in the Tibetan Plateau and the Itui River in the Amazon Basin—were selected for this analysis. By comparing these observations with existing research data, this study quantitatively revealed the lag response patterns in the planform migration processes of meandering rivers. The findings of the study revealed several key insights.(1) The average migration rates for the three rivers were determined to be 1.74, 3.84, and 2.34 m/a, respectively. The critical values of the relative curvature radius for the river channels ranged from 1.5 to 2.0, 1.7 to 2.2, and 2.5 to 3.0, where local migration rate peaks were observed. These findings align with previous research that reported critical values between 2.0 and 4.0.(2) A significant lag is observed in the migration rate relative to curvature in spatial variation, with lag distances for the Black, White, and Itui Rivers measuring 227, 281, and 324 m,corresponding to 2.02, 2.39, and 3.15 times the river width, respectively.(3) A comparison with other meandering rivers indicates that, despite significant variations in climatic and hydrological conditions and river discharges differing by over 1,000times, the ratio of lag distance to river width(relative lag distance) for meandering rivers consistently falls within the range of 2.0to 4.0. This study suggests that the establishment of critical values for the relative curvature radius and the concentration of the relative lag distance reflects distinct quantitative relationships that emerge during the evolutionary processes of meandering rivers, aiming to minimize energy expenditure. These relationships appear to be applicab

关键词： Meandering rivers Remote sensing image Planform extraction Migration rate Lag response

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New progresses of fine-grained sediment gravity-flow deposits and their importance for unconventional shale oil and gas plays

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Petroleum Science 2025年第1期22卷 1-15页

作者： Tian Yang Ying-Lin Liu state key laboratory of Oil and Gas Reservoir Geology and Exploitation (Chengdu University of Technology) Institute of Sedimentary Geology key laboratory of Deep-time Geography and environment Reconstruction and Applications of Ministry of Natural resources Chengdu University of Technology

Fine-grained sediments are widely distributed and constitute the most abundant component in sedimentary systems, thus the research on their genesis and distribution is of great significance. In recent years, fine-grained sediment gravity-flows(FGSGF) have been recognized as an important transportation and depositional mechanism for accumulating thick successions of fine-grained sediments. Through a comprehensive review and synthesis of global research on FGSGF deposition, the characteristics,depositional mechanisms, and distribution patterns of fine-grained sediment gravity-flow deposits(FGSGFD) are discussed, and future research prospects are clarified. In addition to the traditionally recognized low-density turbidity current and muddy debris flow, wave-enhanced gravity flow, lowdensity muddy hyperpycnal flow, and hypopycnal plumes can all form widely distributed FGSGFD. At the same time, the evolution of FGSGF during transportation can result in transitional and hybrid gravityflow deposits. The combination of multiple triggering mechanisms promotes the widespread development of FGSGFD, without temporal and spatial limitations. Different types and concentrations of clay minerals, organic matters, and organo-clay complexes are the keys to controlling the flow transformation of FGSGF from low-concentration turbidity currents to high-concentration muddy debris flows. Further study is needed on the interaction mechanism of FGSGF caused by different initiations, the evolution of FGSGF with the effect of organic-inorganic synergy, and the controlling factors of the distribution patterns of FGSGFD. The study of FGSGFD can shed some new light on the formation of widely developed thin-bedded siltstones within shales. At the same time, these insights may broaden the exploration scope of shale oil and gas, which have important geological significances for unconventional shale oil and gas.

关键词： Fine-grained sediment gravity-flow Depositional mechanism Transportation and evolution Distribution pattern Shale oil and gas

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Emission characteristics,environmental impacts and health risk assessment of volatile organic compounds from the typical chemical industry in China

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Journal of environmental Sciences 2025年第3期149卷 113-125页

作者： Kaitao Chen Xin Gu Min Cai Weicheng Zhao Boxuan Wang Haoran Yang Xingang Liu Xingru Li Analysis and Testing Center Department of ChemistryCapital Normal UniversityBeijing 100048China College of resources environment and Tourism Capital Normal UniversityBeijing 100048China state key laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China

To study the volatile organic compounds(VOCs)emission characteristics of industrial enterprises in China,6 typical chemical industries in Yuncheng City were selected as research objects,including the modern coal chemical industry(MCC),pharmaceutical industry(PM),pesticide industry(PE),coking industry(CO)and organic chemical industry(OC).The chemical composition of 91 VOCs was quantitatively *** results showed that the emission concentration of VOCs in the chemical industry ranged from 1.16 to 155.59 mg/m^(3).Alkanes were the main emission components of MCC(62.0%),PE(55.1%),and OC(58.5%).Alkenes(46.5%)were important components of PM,followed by alkanes(23.8%)and oxygenated volatile organic compounds(OVOCs)(21.2%).Halocarbons(8.6%-71.1%),OVOCs(9.7%-37.6%)and alkanes(11.2%-27.0%)were characteristic components of *** largest contributor to OFP was alkenes(0.6%-81.7%),followed by alkanes(9.3%-45.9%),and the lowest onewas alkyne(0%-0.5%).Aromatics(66.9%-85.4%)were the largest contributing components to SOA generation,followed by alkanes(2.6%-28.5%),and the lowest one was alkenes(0%-4.1%).Ethylene and BTEX were the key active species in various chemical *** human health risk assessment showed workers long-term exposed to the air in the chemical industrial zone had a high cancer and non-cancer risk during work,and BTEX and dichloromethane were the largest contributors.

关键词： Industrial enterprise VOCs spectrum Reactivity Health risk

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Facilitation of microbialite development by continental weathering in the Cambrian Zhangxia Formation,southern North China Block

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Journal of Palaeogeography 2025年第1期14卷 172-185页

作者： Wen-Tao Yang Jia-Qi Zhu Min Wang Chao Liu Yong-An Qi School of resources and environment Henan Polytechnic University key laboratory of Biogenic Traces and Sedimentary Minerals of Henan Province Henan Polytechnic University state key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of Sciences

We report geochemical data for carbonate rocks from the Cambrian Zhangxia Formation,southern North China Block,including trace-element contents and C,O,and Sr isotopic compositions,to determine the controls on the development of microbialites in this *** sedimentary environment of the Zhangxia Formation evolved from carbonate-slope through platform-margin-reef to ooid-shoal,and then to open-platform settings,corresponding to the development of micrites,microbialites,and oolitic *** data show that δ13C values decrease upwards through the Zhangxia Formation,from 0.99‰to-1.59‰,whereas δ18O values increase from-9.91‰to-7.10‰.Total rare earth element （REE）contents decrease upwards through the stratigraphy,and the contents of Th and Sc show a similar trend.87Sr/86Sr ratios reach a maximum of 0.710544 in the horizons of microbialite development,Member 2 of the Zhangxia Formation,above which the ratios are uniform,with a mean value of *** these geochemical data with the inferred sedimentary evolution,the Zhangxia Formation is interpreted to have formed in a depositional environment that changed from transgression to *** weathering played a crucial role in promoting the input of terrigenous materials,which in turn favored the development of microbialites during the early stage of deposition of the Zhangxia Formation.

关键词： Carbonate rocks Trace elements C and Sr isotopes Microbialites Cambrian

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Propagation criterion of hydraulic fracture in rock based on the rock micro-cracking mechanism

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International Journal of Mining Science and Technology 2025年第3期35卷 433-449页

作者： Qingwang Cai Bingxiang Huang Xinglong Zhao Yuekun Xing School of resources environment and Safety Engineering University of South ChinaHengyang 421001 China state key laboratory for Fine Exploration and Intelligent Development of Coal resources China University of Mining and TechnologyXuzhou 221116 China

Hydraulic fracture(HF)formed in rock significantly helps with the development of geo-energy and *** HF formation condition was challenging to understand,with obscure rock micro-cracking mechanisms being a key *** rock micro-cracking mechanism under gradient pore water pressure was analyzed on the scale of mineral particles and it was combined with macroscopic boundary conditions of rock hydraulic fracturing,obtaining the propagation criterion of HF in rock based on the rock micro-cracking mechanism which was verified by *** results show that the disturbed skeleton stress induced by the disturbance of gradient pore water pressure in rock equals the pore water pressure *** overall range of the defined mechanical shape factor a/b is around 1,but greater *** the combined influence of pore water pressure differences and macroscopic boundary stresses on the rock micro-cracking,micro-cracks form among rock mineral particles,micro-cracks connect to form micro-hydraulic fracture surfaces,and micro-hydraulic fracture surfaces open to form macrohydraulic *** begins to form at the micro-cracking initiation pressure(MCIP),which was tested by keeping the HF tip near the initiation *** theoretical value of MCIP calculated by the proposed propagation criterion is close to MCIP tested.

关键词： Hydraulic fracture Propagation criterion Micro-cracking mechanism Pore pressure Stress singularity

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New Potential Barite Reference Materials for LA-MC-ICP-MS Sulfur Isotope Analysis with Application to Hydrothermal Barite in the Huayangchuan Deposit,Western China

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Journal of Earth Science 2025年第1期36卷 1-10页

作者： Jiali Fu Xinqian He Zhaochu Hu Shuo Yin Jian Ma Kaiyun Chen Wen Zhang National key laboratory of Uranium Resource Exploration-Mining andnuclear Remote Sensing East China UniversityofTechnologyNanchang 330013China state key laboratory of nuclear resources and environment East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China state key laboratory of Geological Processes and Mineral resources China University of GeosciencesWuhan 430078China state key laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences,especially in ore deposits where sulfide-sulfate pair coprecipitates ***,in-situ S isotope determination of barite is challenging without natural matrix-matched reference *** this study,we present two natural barite reference materials(1-YS and 294-YS)for in-situ sulfur isotopic *** LA-MC-ICP-MS laboratories were utilized to test theδ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than±0.45‰and±0.41‰,***,the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within *** grand meanδ~(34)S values of 1-YS(13.37‰±0.42‰,2s)and 294-YS(14.38‰±0.44‰,2s)are the final recommended values obtained from four independent *** the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic ***,the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit(Qinling orogenic belt,western China)to obtainδ34S *** the temperaturedependentδ34S fractionation of barite-pyrite pair,we calculate the formation temperature of barite(i.e.,506 to 537°C)and theδ34S value of mineralizing fluid(i.e.,-7.11‰to-7.59‰)in the Huayangchuan *** results indicate an involvement of sedimentary sulfur,presumably acting as a potential uranium source(e.g.,upper crustal materials)for the giant Huayangchuan deposit.

关键词： LA-MC-ICP-MS S isotope reference material barite geothermometry

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Dissolved organic matter characteristics linked to bacterial community succession and nitrogen removal performance in woodchip bioreactors

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Journal of environmental Sciences 2025年第2期148卷 625-636页

作者： Achen Wang Xiang Li Xuesong Luo Guangwen He Daqing Huang Qiaoyun Huang Xue-Xian Zhang Wenli Chen National key laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070China Hubei key laboratory of Soil environment and Pollution Remediation College of Resources and EnvironmentHuazhong Agricultural UniversityWuhan 430070China School of Natural Sciences Massey University at AlbanyAuckland 0745New Zealand

Woodchip bioreactors are an eco-friendly technology for removing nitrogen(N)***,there needs to be more clarity regarding the dissolved organicmatter(DOM)characteristics and bacterial community succession mechanisms and their association with the N removal performance of *** laboratory woodchip bioreactors were continuously operated for 360 days under three influent N level treatments,and the results showed that the average removal rate of TN was 45.80 g N/(m^(3)·day)when the influent N level was 100 mg N/L,which was better than 10 mg N/L and 50 mg N/*** succession of bacterial communities in response to influent N levels and DOM characteristics was an important driver of TN removal *** to high N levels enriched a copiotroph bacterial module(Module 1)detected by network analysis,including Phenylobacterium,Xanthobacteraceae,Burkholderiaceae,Pseudomonas,and Magnetospirillaceae,carrying N-cycle related genes for denitrification and ammonia assimilation by the rapid consumption of *** a process can increase carbon limitation to stimulate local organic carbon decomposition to enrich oligotrophswith fewer N-cycle potentials(Module 2).Together,this study reveals that the compositional change ofDOMand bacterial community succession are closely related to N removal performance,providing an ecological basis for developing techniques for N-rich effluent treatment.

关键词： Bacterial community succession Dissolved organic matter N removal performance Woodchip bioreactors

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