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西南典型碳酸盐岩高地质背景区农田重金属化学形态、影响因素及回归模型

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环境科学 2024年第5期45卷 2995-3004页

作者：唐瑞玲徐进力刘彬杜雪苗顾雪于林松毕婧中国地质科学院地球物理地球化学勘查研究所廊坊065000 山东省物化探勘查院济南250013 山东省地质测绘院济南250014

土壤重金属化学形态是决定重金属生物活性和生物毒性的重要因素,是科学评价西南碳酸盐岩高地质背景区土壤重金属生态风险的关键.为了探明碳酸盐岩高地质背景区土壤重金属化学形态分布情况,选择贵州省典型碳酸盐岩分布区,以第二次全国土... 详细信息

土壤重金属化学形态是决定重金属生物活性和生物毒性的重要因素,是科学评价西南碳酸盐岩高地质背景区土壤重金属生态风险的关键.为了探明碳酸盐岩高地质背景区土壤重金属化学形态分布情况,选择贵州省典型碳酸盐岩分布区,以第二次全国土壤普查图斑为采样单元,在农田中采集土壤表层样品309件,利用改进的Tessier七步顺序提取法,分析了As、Cd、Cu、Hg、Ni、Pb和Zn等7种重金属的水溶态(F1)、离子交换态(F2)、碳酸盐结合态(F3)、弱有机结合态(F4)、铁锰氧化物结合态(F5)、强有机结合态(F6)和残渣态(F7)这7种化学形态.结果发现,土壤中重金属As、Cu、Hg、Ni、Pb和Zn残渣态比例均超过50%,有效组分(F1~F3)比例均小于5%,潜在生物有效组分(F4~F6)比例低于45%,活性较低,生态风险不高.Cd的有效组分和潜在生物有效组分占比分别为55.49%和29.37%,远高于其他重金属,基于土壤重金属形态的生态风险远小于基于土壤总量的生态风险.逐步回归方程可以有效建立Cd、Cu和Pb生物有效组分与影响因素之间的关系.重金属全量和pH值是影响碳酸盐岩高地质背景区土壤重金属化学形态的重要因子,受研究区长期土法炼锌活动和碳酸盐岩风化成土过程中重金属元素倾向于在残渣态中富集的影响,土壤有机质(OM)和氧化物含量对土壤重金属化学形态影响相对较小.

关键词：土壤重金属化学形态生态评价影响因素回归模型高地质背景区

Active Authentication Protocol for IoV Environment with Distributed Servers

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Computers, Materials & Continua 2022年第12期73卷 5789-5808页

作者： Saravanan Manikandan Mosiur Rahaman yu-lin song Department of Computer Science and Information Engineering Asia UniversityTaichungTaiwan Bioinformatics and Medical Engineering Asia UniversityTaichungTaiwan

The Internet of Vehicles(IoV)has evolved as an advancement over the conventional Vehicular Ad-hoc Networks(VANETs)in pursuing a more optimal intelligent transportation system that can provide various intelligent solutions and enable a variety of applications for vehicular *** volumes of data are produced and communicated wirelessly among the different relayed entities in these vehicular networks,which might entice adversaries and endanger the system with a wide range of security *** ensure the security of such a sensitive network,we proposed a distributed authentication mechanism for IoV based on blockchain technology as a distributed ledger with an ouroboros *** timestamp and challenge-responsemechanisms,the proposed authentication model can withstand several security attacks such asMan-in-Middle(MiM)attacks,Distributed Denial of Service(DDoS)attacks,server spoofing attacks and *** proposed method also provides a solution for single-point failure,forward secrecy,revocability,*** exhibit the security of our proposed model by using formal(mathematical)analysis and informal *** used Random Oracle Model to perform themathematical *** addition,we compared the communication cost,computation cost,and security of the proposed model with the related existing *** have verified the security of the model by using AVISPA tool *** security analysis and computation analysis show that the proposed protocol is viable.

关键词： IoV message authentication random oracle model blockchain distributed server revocability

Derivative Formula and Coupling Property for linear SDEs Driven by Lévy Processes

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 708-721页

作者： Zhao DONG yu-lin song Ying-chao XIE Institute of Applied Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sci- ences Beijing 100190 China School of Mathematical Sciences Beijing Normal University Beijing 100875 China School of Mathematics and Statistics Jiangsu Normal University Jiangsu Province Xuzhou 221116 China

In this paper we investigate an integration by parts formula for Lévy processes by using lower bound conditions of the corresponding Lévy measure. As applications, derivative formula and coupling property are derive... 详细信息

关键词： Lévy processes integration by parts formula derivative formula coupling property

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红外偏振探测器融合成像研究

红外 2024年第5期45卷 23-27页

作者：程雨陈彦冠邢艳蕾喻松林华北光电技术研究所北京100015

分析了红外偏振探测器对于探测识别红外伪装目标以及红外暗弱目标的重要应用意义。详细介绍了物体的红外偏振特性及其表示方法,并阐述了红外偏振特性的影响因素。最后重点介绍了偏振成像融合算法。步骤分为数据预处理、红外偏振融合和... 详细信息

分析了红外偏振探测器对于探测识别红外伪装目标以及红外暗弱目标的重要应用意义。详细介绍了物体的红外偏振特性及其表示方法,并阐述了红外偏振特性的影响因素。最后重点介绍了偏振成像融合算法。步骤分为数据预处理、红外偏振融合和融合图像再处理。本文对研究红外偏振探测器融合成像具有重要意义。

关键词：红外偏振探测器融合成像红外伪装

Comparison of models to predict air infiltration rate of buildings with different surrounding environments

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Building Simulation 2024年第6期17卷 1007-1021页

作者： Shu Zheng Xiujiao song lin Duanmu yu Xue Xudong Yang Department of Building Science Tsinghua UniversityBeijing100084China School of Civil Engineering Dalian University of TechnologyDalian116024China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan030032China

The air infiltration rate of buildings strongly influences indoor environment and energy *** this study,several traditional methods for determining the air infiltration rate were compared,and their accuracy in different scenarios was ***,a method combining computational flow dynamics(CFD)with the Swami and Chandra(S-C)model was developed to predict the influence of the surrounding environment on the air infiltration *** buildings in Dalian,China,were selected:one with a simple surrounding environment and the other with a complex surrounding environment;their air infiltration rates were *** test results were used to validate the accuracy of the air infiltration rate solution models in different urban *** the building with a simple environment,the difference between the simulation and experimental results was 0.86%–22.52%.For the building with a complex environment,this difference ranged from 17.42%to 159.28%.We found that most traditional models provide accurate results for buildings with simple surrounding and that the simulation results widely vary for buildings with complex *** results of the method of combining CFD with the S-C model were more accurate,and the relative error between the simulation and test results was 10.61%.The results indicate that the environment around the building should be fully considered when calculating the air infiltration *** results of this study can guide the application of methods of determining air infiltration rate.

关键词： air infiltration rate models CFD simulation building surrounding air infiltration rate test

Revealing the specific role of sulfide and nano-alumina in composite solid-state electrolytes for performance-reinforced ether-nitrile copolymers

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Journal of Energy Chemistry 2024年第4期91卷 628-636页

作者： Haoyang yuan Changhao Tian Mengyuan song Wenjun lin Tao Huang Aishui yu Department of Chemistry Collaborative Innovation Center of Chemistry for Energy MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsInstitute of New EnergyFudan UniversityShanghai 200438China Laboratory of Advanced Materials Fudan UniversityShanghai 200438China

Composite solid-state electrolytes represent a critical pathway that balances the interface compatibility and lithium-ion conductivity in all-solid-state *** quest for stable and highly ion-conductive combinations between polymers and fillers is vital,but blind attempts are often made due to a lack of understanding of the mechanisms involved in the interaction between polymers and ***,we employ in-situ polymerization to prepare a polymer based on an ether-nitrile copolymer with high cathode stability as the foundation and discuss the performance enhancement mechanisms of argyrodite and *** 1%content of sulfide interacting with the polymer at the two-phase interface,the local enhancement of lithium-ion migration capability can be achieved,avoiding the reduction in capacity due to the low ion conductivity of the passivation layer during *** capacity retention after 50cycles at 0.5 C increases from 83.5%to 94.4%.Nano-alumina,through anchoring the anions and interface inhibition functions,eventually poses an initial discharge capacity of 136.8 m A h g^(-1)at 0.5 C and extends the cycling time to 1000 h without short-circuiting in lithium metal *** the combined action of dual fillers on the composite solid-state electrolyte,promising insights are provided for future material design.

关键词： Composite solid-state electrolytes Lithium metal anode Dual fillers Interfacial ionic conduction Inert nano-alumina

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-lin Fan Feng Zhang Qian Chen Hao-Chen song Lu-yu Zhong yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma yu Hou Ba Li He-song Zhang Qing-you Liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

A multi-mechanism numerical simulation model for CO_(2)-EOR and storage in fractured shale oil reservoirs

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Petroleum Science 2024年第3期21卷 1814-1828页

作者： yuan-Zheng Wang Ren-Yi Cao Zhi-Hao Jia Bin-yu Wang Ming Ma lin-song Cheng College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China John&Willie Leone Department of Energy&Mineral Engineering The Pennsylvania State UniversityUniversity Park16802PA.USA

Under the policy background and advocacy of carbon capture,utilization,and storage(CCUS),CO_(2)-EOR has become a promising direction in the shale oil reservoir *** multi-scale pore structure distribution and fracture structure lead to complex multiphase flow,comprehensively considering multiple mechanisms is crucial for development and CO_(2) storage in fractured shale *** this paper,a multi-mechanism coupled model is developed by *** to the traditional Eclipse300 and MATLAB Reservoir Simulation Toolbox(MRST),this model considers the impact of pore structure on fluid phase behavior by the modified Peng—Robinson equation of state(PR-EOS),and the effect simultaneously radiate to Maxwell—Stefan(M—S)diffusion,stress sensitivity,the nano-confinement(NC)***,a modified embedded discrete fracture model(EDFM)is used to model the complex fractures,which optimizes connection types and half-transmissibility calculation approaches between non-neighboring connections(NNCs).The full implicit equation adopts the finite volume method(FVM)and Newton—Raphson iteration for discretization and *** model verification with the Eclipse300 and MRST is *** results show that the interaction between the mechanisms significantly affects the production performance and storage *** effect of molecular diffusion may be overestimated in oil-dominated(liquid-dominated)shale *** well spacing and injection gas rate are the most crucial factors affecting the production by sensitivity ***,the potential gas invasion risk is *** model provides a reliable theoretical basis for CO_(2)-EOR and sequestration in shale oil reservoirs.

关键词： CO_(2)-EOR CO_(2)storage Shale oil reservoir Complex fracture model Multiple mechanisms