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Genesis of geothermal water in the hinterland of Guanzhong Basin， China: Insight from hydrochemical and isotopic analysis

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Journal of Earth Science 2025年

作者： Jiangxia Wang Panpan Xu Hui Qian Yongqi Zang Qiming Wang Zhiyuan Ma School of Water and environment， Chang'an University Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region of the ministry of Education， Chang'an University Key Laboratory of Eco-hydrology and Water Security in Arid and Semi-arid Regions of ministry of Water resources， Chang'an University

The Guanzhong Basin， located in Shaanxi Province， China， has abundant geothermal resources in its hinterland. Focusing on typical thermal reservoir structural units， namely the Xianli fault-step (XL) and Xi'an depression (XA)， this study reveals the genesis of geothermal water by combining hydrochemistry and environmental isotopes. The geothermal waters of XL uniformly correspond to the Na-Cl type with high contents of major ions， while the geothermal water of XA has complex hydrochemical types. The quartz geothermometer (with maximum steam loss) and Na-K-Ca geothermometer are recommended for XL and the quartz geothermometer (with no and maximum steam loss) and Na-K geothermometer for XA. Their temperature ranges are 99-159℃ and 93-146℃， respectively. The circulation depth of geofluids in XL and XA range from 2579 to 4766 m and from 2541 to 4330 m， with mean apparent ages of 21543 and 20345 yr B.P.， respectively. The geothermal water in XL originates from a mixture of sedimentary water and ancient infiltration water， and its formation mode was the vertical heat conduction with cooling process. In contrast， the geothermal water in XA originates from the dual process of cooling and mixing， with the process being dominated by ancient infiltration water and supplementation by modern infiltration water.

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Energy injection,transport,and dissipation in Earth's magnetosphere

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Science China Earth Sciences 2025年

作者： Huishan FU Jinbin CAO School of Space and Earth Sciences Beihang University Key Laboratory of Space environment Monitoring and Information Processing Ministry of Industry and Information Technology

The Earth's magnetosphere is a region occupied by many artificial satellites, and also is a region that spacecraft must cruise during the deep-space exploration. In this sense, the Earth's magnetosphere is closely related to human activity and is a candidate for us to expand our living space. Generally, the Earth's magnetosphere can preclude most energetic particles from the Sun and the interstellar space, effectively protecting human beings on the Earth from being attacked and thus making the Earth to be a habitable planet. However, in some conditions, the Earth's magnetosphere becomes dynamic and energetic, and consequently may damage the artificial satellites, threaten the astronauts' health, and disrupt the ground infrastructure, which leads to a decline in the national economy. Therefore, investigating how energy is injected into the magnetosphere, how it is transported in the magnetosphere, and how it is ultimately dissipated in the magnetosphere are the key issues in space physics. Targeting these key issues, in this paper, we review the recent progress on them. Particularly, we introduce the relevant scientific questions,models, methods, and spacecraft missions, for better building a physical link among the energy injection, transport, and dissipation in the magnetosphere, present an energy chain of the magnetosphere, reveal the relationship between such energy chain and the space weather events, and discuss the forecasting and warning methods for energetic-particle events in the magnetosphere. The magnetospheric energy chain discussed in this paper will help us reveal the mechanisms of space weather events, establish the models of space environment, and forecast the disastrous space weather events.

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Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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Science China Earth Sciences 2025年第1期68卷 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of resources and environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

关键词： Mangrove Tupu Knowledge graph Multi-modal Knowledge service

Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China Chemistry 2025年第1期68卷 181-185页

作者： Yanping Xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

Experimental Research on a Feasible Building Insulation Material Based Reed in China

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Journal of Thermal Science 2025年第1期34卷 176-187页

作者： LIU Tiantian PENG Yizhe LIU Lifang CAI Chenghan WANG Shuang LI Hongqiang College of Civil Engineering Hunan University College of Civil Engineering Hunan University of Science and Technology School of Energy and Power Jiangsu University of Science and Technology National Center for International Research Collaboration in Building Safety and environment (NCIRCBSE) Hunan University Key Laboratory of Building Safety and Energy Efficiency of the ministry of Education Hunan University

The seemingly useless reeds are prepared as thermal insulation materials,which not only meet the requirements of environmental sustainability but also enhance the added value of reeds,creating new economic *** hydrophobicity of raw biomass surfaces leads to problems such as weak bonding strength and non-dense structure in the formed materials,as well as issues related to the residual insect infestations on the *** this study,reed straw was used as the raw material,and foamed geopolymer was used as the binder to prepare building insulation materials based *** improve the interfacial adhesion performance between reed straw and foamed geopolymer,a thermochemical modification method-thermal carbonization,was *** this study,the mechanical properties and hydraulic properties of the studied materials with different degrees of surface thermal modification were tested,especially the fire resistance performance,and weathering resistance performance rarely found in published *** the surface thermal modification condition of reed straw was 250℃（30 min）,the comprehensive performance of reed-based building insulation materials was the best,when the studied material density was 321.3 kg/m3;the compressive strength was 0.59 MPa;the thermal conductivity was 0.101 W/（m·K）;the pH was 11.27;the moisture absorption rate was 25.1%,and the compressive strength loss rate in wet-dry cycles was 18.5%.In addition,it had excellent fire resistance performance and weathering resistance *** new material can be widely used to improve the thermal insulation of traditional buildings and as sandwich filler in prefabricated buildings,such as preparing insulating walls.

关键词： building insulation material based reed fire resistance performance interface adhesion properties pre-treatment of reeds weathering resistance performance

Seasonal differences in sources and formation processes of PM2.5 nitrate in an urban environment of North China

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Journal of environmental Sciences 2022年第10期34卷 94-104页

作者： Yanli Li Yaping Geng Xiaomian Hu Xijie Yin Institute of resources and environment Henan Polytechnic UniversityJiaozuo 454000China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361000China

Nitrate(NO_(3)^(−))has been the dominant ion of secondary inorganic aerosols(SIAs)in PM_(2.5) in North *** the formation mechanisms and sources of particulate nitrate are vital to mitigate air *** this study,PM_(2.5) samples in winter(January 2020)and in summer(June 2020)were collected in Jiaozuo,China,andwater-soluble ions and(δ_(15)N,δ_(18)O)-NO_(3)^(−)were *** results showed that the increase of NO_(3)^(−)concentrations was the most remarkable with increasing PM_(2.5) pollution level.δ_(18)O-NO_(3)^(−)values for winter samples(82.7‰ to 103.9‰)were close to calculated δ_(18)O-HNO_(3)(103‰±0.8‰)values by N_(2)O_(5) pathway,while δ_(18)O-NO_(3)^(−)values(67.8‰ to 85.7‰)for summer samples were close to calculated δ_(18)O-HNO_(3) values(61‰±0.8‰)by OH oxidation pathway,suggesting that PM_(2.5) nitrate is largely from N_(2)O_(5) pathway inwinter,while is largely from OH pathway in *** fractional contributions of P_(N2O5+H2O) were 70% and 39% in winter and summer sampling periods,respectively,those of POH were 30% and 61%,*** δ_(15)N-NO_(3)−values for winter samples(3.0‰to 14.4‰)than those for summer samples(-3.7‰to 8.6‰)might be due to more contributions from coal combustion in *** combustion(31%±9%,25%±9%in winter and summer,respectively)and biomass burning(30%±12%,36%±12%in winter and summer,respectively)were the main sources using Bayesian mixing *** results provided clear evidence of particulate nitrate formation and sources under different PM_(2.5) levels,and aided in reducing atmospheric nitrate in urban environments.

关键词： PM_(2.5) Dual isotopes Nitrate formation pathways Bayesian mixing model

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Quantitative reconstruction of salinity and precipitation changes in Central Asia over the past 3200 years using diatom and pollen records of lacustrine sediment in Aibi Lake of SW Junggar Basin

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Journal of Earth Science 2025年

作者： Long Pan Guoqiang Li Xiaoyan Wang Ming Jin Xinrong He Luo Qin Zhong Wang Wenwei Zhao Chunzhu Chen Yuanlu Liu Jin Yang Lele Shu Key Laboratory of Western China's environmental Systems (ministry of Education)， College of Earth and environmental Sciences， Lanzhou University College of Earth Sciences， Chengdu University of Technology School of Geographic Science， Nantong University Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions， Northwest Institute of Eco-environment and resources， Chinese Academy of Sciences

The response of lake environments in arid Central Asia to climate change during the Late Holocene over the centennial to millennial timescales remains contentious. The reason that primarily paleoenvironmental proxies interpreting diverse and the scarcity of accurate quantitative reconstruction records. In this study， we employed diatoms and pollen records from lacustrine sediment in the Aibi Lake of SW Junggar Basin to quantitatively reconstruct salinity and watershed precipitation amounts while exploring the associated forcing mechanism. The results indicate that Aibi Lake salinity varied between 2 g/L and 47 g/L during the Late Holocene period， indicating a generally brackish environment， and corresponding to prevailing Tryblionella granulata diatom in the lake basin. Westerly-dominated annual precipitation varied between 250 mm and 320 mm during the Late Holocene period in the basin， exhibiting a generally semi-arid environment and prevailing desert steppe vegetation. The Aibi Lake has a low salinity of average value of ～15 g/L. It exhibits elevated precipitation (average value of ～280 mm) during the periods of the Roman Warm Period (2900-1990 cal yr BP)， Dark Age Cold Period (1570-1140 cal yr BP)， and Little Ice Age (590-120 cal yr BP). The reconstructed precipitation and salinity exhibit a periodicity of ～200 years， which is consistent with the cycle of phase changes of the North Atlantic Oscillation (NAO) and Total Solar Irradiance (TSI). This correlation suggests that variations in NOA and TSI significantly influence the precipitation and salinity changes in Central Asia over centennial to millennial timescales.

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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of forest resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

LiDAR-Visual SLAM with Integrated Semantic and Texture Information for Enhanced Ecological Monitoring Vehicle Localization

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Computers, Materials & Continua 2025年第1期82卷 1401-1416页

作者： Yiqing Lu Liutao Zhao Qiankun Zhao Foreign environmental Cooperation Center Ministry of Ecology and Environment of PRCBeijing100035China Beijing Computing Center Co. Ltd.Beijing Academy of Science and TechnologyBeijing100083China Beijing Guyu Interactive Artificial Intelligence Application Co. Ltd.Beijing100024China

Ecological monitoring vehicles are equipped with a range of sensors and monitoring devices designed to gather data on ecological and environmental *** vehicles are crucial in various fields,including environmental science research,ecological and environmental monitoring projects,disaster response,and emergency management.A key method employed in these vehicles for achieving high-precision positioning is LiDAR(lightlaser detection and ranging)-Visual Simultaneous Localization and Mapping(SLAM).However,maintaining highprecision localization in complex scenarios,such as degraded environments or when dynamic objects are present,remains a significant *** address this issue,we integrate both semantic and texture information from LiDAR and cameras to enhance the robustness and efficiency of data ***,semantic information simplifies the modeling of scene elements,reducing the reliance on dense point clouds,which can be less ***,visual texture information complements LiDAR-Visual localization by providing additional contextual *** incorporating semantic and texture details frompaired images and point clouds,we significantly improve the quality of data association,thereby increasing the success rate of *** approach not only enhances the operational capabilities of ecological monitoring vehicles in complex environments but also contributes to improving the overall efficiency and effectiveness of ecological monitoring and environmental protection efforts.

关键词： LiDAR-Visual simultaneous localization and mapping integrated semantic texture information