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Thermo-hydro-mechanical (THM) coupled simulation of the land subsidence due to aquifer thermal energy storage (ATES) system in soft soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 1952-1966页

作者： Yang Wang fengshou Zhang Fang liu Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China Shanghai Engineering and Technology Research Center of Shallow Geothermal Energy Shanghai200072China

Aquifer thermal energy storage(ATES)system has received attention for heating or cooling buildings.However,it is well known that land subsidence becomes a major environmental concern for ATES projects.Yet,the effect of temperature on land subsidence has received practically no attention in the past.This paper presents a thermo-hydro-mechanical(THM)coupled numerical study on an ATES system in Shanghai,China.Four water wells were installed for seasonal heating and cooling of an agriculture greenhouse.The target aquifer at a depth of 74e104.5 m consisted of alternating layers of sand and silty sand and was covered with clay.Groundwater level,temperature,and land subsidence data from 2015 to 2017 were collected using field monitoring instruments.Constrained by data,we constructed a field scale three-dimensional(3D)model using TOUGH(Transport of Unsaturated Groundwater and Heat)and FLAC3D(Fast Lagrangian Analysis of Continua)equipped with a thermo-elastoplastic constitutive model.The effectiveness of the numerical model was validated by field data.The model was used to reproduce groundwater flow,heat transfer,and mechanical responses in porous media over three years and capture the thermo-and pressure-induced land subsidence.The results show that the maximum thermoinduced land subsidence accounts for about 60%of the total subsidence.The thermo-induced subsidence is slightly greater in winter than that in summer,and more pronounced near the cold well area than the hot well area.This study provides some valuable guidelines for controlling land subsidence caused by ATES systems installed in soft soils.

关键词： Aquifer thermal energy storage(ATES) Land subsidence TOUGH-FLAC3D Thermo-elastoplastic constitutive model

Evaluation of fault stability and seismic potential for Hutubi underground gas storage due to seasonal injection and extraction

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Underground Space 2023年第6期13卷 74-85页

作者： Cexuan liu fengshou Zhang Quan Wang Bin Wang Qi Zhang Bin Xu Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China Key Laboratory of Geotechnical&Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China China National Petroleum Company Xinjiang Oil FieldKaramayXinjiang 834000China School of Civil Engineering Southeast UniversityNanjing 211189China Origin Geomechanics Inc. CalgaryAlbertaT3H 0X6Canada Department of Civil Engineering University of CalgaryCalgaryAlbertaT2N 1N4Canada

The Hutubi gas field was put into production in 1998 and then converted into an underground gas storage(UGS)facility in 2013,and since then a cluster of earthquakes associated with seasonal injection and extraction activities have been recorded nearby.To evaluate the fault stability and seismic potential,we established a pseudo-3D geomechanical model to simulate the process of seasonal injection and extraction.Reservoir pore pressures from 1998 to 2019 were obtained through multiphase reservoir simulation and validated by history matching the field injection and production data.We then imported pore pressures into the geomechanical model to simulate the poroelastic perturbation on faults for over 20 years.The fidelity of this model was validated by comparing the simulated surface deformation with global positioning system(GPS)measured data.We used Coulomb failure stress(CFS)as the indicator for the likelihood of fault slippage.The simulation results show that the location of the induced earthquake cluster was within the positive Coulomb stress perturbation(DCFS)area,in which fault slippage was promoted.In addition,DCFS at the earthquake location kept increasing after the injection began.These findings could explain the induced earthquakes with the Coulomb failure stress theory.Furthermore,we conducted a parameter sensitivity study on the dominant factors such as the maximum operating pressure(MOP),frictional coefficient,and dip angle of the pre-existing fault.The results indicate that the magnitude of DCFS caused by seasonal injection and extraction decreases with distance;MOPs are constrained to 32.9,36.2,and 39.5 MPa according to different DCFS thresholds;the critical dip angle ranges are 0-20°and 80°-100°;and strengthening the fault friction can either increase or decrease the seismic potential.This study can help determine the MOP for Hutubi underground gas storage(HTB UGS)and provide a framework for simulating the potential causes of induced seismicity for other sites.

关键词： Underground gas storage Fault stability Seismic potential GPS Induced earthquake Coulomb stress perturbation

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氯氟醚菌唑在黄瓜上的残留及膳食风险评估

植物保护 2024年第1期50卷 225-231页

作者：刘荣荣郭庆刘慧君吴小虎徐军潘兴鲁董丰收郑永权北京农学院北京102206 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193

为评价氯氟醚菌唑在黄瓜中残留产生的膳食摄入风险,于2017年-2018年进行了2年12地规范残留试验,建立了黄瓜中氯氟醚菌唑的超高效液相色谱-串联质谱(UPLC-MS/MS)分析检测方法,并对我国一般人群进行了膳食摄入风险评估。样品经乙腈提取,C1... 详细信息

为评价氯氟醚菌唑在黄瓜中残留产生的膳食摄入风险,于2017年-2018年进行了2年12地规范残留试验,建立了黄瓜中氯氟醚菌唑的超高效液相色谱-串联质谱(UPLC-MS/MS)分析检测方法,并对我国一般人群进行了膳食摄入风险评估。样品经乙腈提取,C18净化,UPLC-MS/MS检测,外标法定量。结果表明:在0.01~1 mg/kg添加水平下,氯氟醚菌唑的平均回收率为90%~108%,相对标准偏差(relative standard deviation, RSD)为3%~12%,定量限(limit of quantification, LOQ)为0.01 mg/kg。400 g/L氯氟醚菌唑悬浮剂按有效成分150 g/hm2施药3次,于末次施药后1、3、5 d采样测定,黄瓜中氯氟醚菌唑残留量为<0.01~0.64 mg/kg。膳食摄入风险评价结果显示:我国一般人群的氯氟醚菌唑国家估计每日摄入量(national estimates of daily intake, NEDI)为0.217 0 mg,风险商(risk quotient, RQ)为6.9%,表明氯氟醚菌唑在黄瓜中残留不会对一般人群健康造成不可接受的风险。

关键词：氯氟醚菌唑黄瓜超高效液相色谱-串联质谱残留风险评估

维普期刊数据库

Objective Forecast Method of Frost in Lianyungang City

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Meteorological and Environmental Research 2014年第8期5卷 23-27页

作者： Ren Shuxia Zhang Lihua Jia Yihong liu fengshou Lianyungang Meteorological Bureau in Jiangsu Province Xuzhou Meteorological Bureau in Jiangsu Province Guanyun Meteorological Bureau in Lianyungang City of Jiangsu

Based on annual minimum air temperature, the minimum ground temperature, cloudiness, air pressure, wind velocity in Lianyungang City during 1971 -2010 and sounding geopotential height, wind direction, dew point and temperature at related stations, using mathematical stepwise regression method and SPSS statistical software, short-term prediction equations of daily minimum air temperature and daily minimum ground temperature at the observation station were established. According to the relationships between frost and temperature, ground temperature, based on local frost forecast standard, the short-term forecast equation was used to judge if frost occurred in Lianyungang City. Via real-time weather mo- nitoring, accurate and fine forecast and early warning, short-term objective forecast business system of frost in Lianyungang was established for a full range of effective service.

关键词： Frost Objective forecast Lianyungang China

Wireless Self-Powered Vibration Sensor System for Intelligent Spindle Monitoring

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Structural Durability & Health Monitoring 2023年第4期17卷 315-336页

作者： Lei Yu Hongjun Wang Yubin Yue Shucong liu Xiangxiang Mao fengshou Gu Intelligent Sensing and Control of High-End Equipment Beijing International Science and Technology Cooperation Base Beijing Information Science and Technology UniversityBeijing100192China Machinery Technology Development Co Ltd.Beijing100044China Centre for Efficiency and Performance Engineering University of HuddersfieldQueensgateHuddersfieldWest YorkshireHD1-3DHUK

In recent years,high-end equipment is widely used in industry and the accuracy requirements of the equipment have been risen year by year.During the machining process,the high-end equipment failure may have a great impact on the product quality.It is necessary to monitor the status of equipment and to predict fault diagnosis.At present,most of the condition monitoring devices for mechanical equipment have problems of large size,low precision and low energy utilization.A wireless self-powered intelligent spindle vibration acceleration sensor system based on piezoelectric energy harvesting is proposed.Based on rotor sensing technology,a sensor is made to mount on the tool holder and build the related circuit.Firstly,the energy management module collects the mechanical energy in the environment and converts the piezoelectric vibration energy into electric energy to provide 3.3 Vfor the subsequent circuit.The lithium battery supplies the system with additional power and monitors’the power of the energy storage circuit in real-time.Secondly,a three-axis acceleration sensor is used to collect,analyze and filter a series of signal processing operations of the vibration signal in the environment.The signal is sent to the upper computer by wireless transmission.The host computer outputs the corresponding X,Y,and Z channel waveforms and data under the condition of the spindle speed of 50∼2500 r/min with real-time monitoring.The KEIL5 platform is used to develop the system software.The small-size piezoelectric vibration sensor with high-speed,high-energy utilization,high accuracy,and easy installation is used for spindle monitoring.The experiment results show that the sensor system is available and practical.

关键词： Condition monitoring self-powered vibration acceleration sensor piezoelectric energy harvesting wireless transmission

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2,6-二氟苯胺的回收工艺研究

山西化工 2024年第2期44卷 26-27页

作者：刘振兴田俊杰于丽宋丰收德州绿霸精细化工有限公司山东德州253000

2,6-二氟苯胺是合成双氟磺草胺的重要原料和溶剂,投料量是反应所需量的4~5倍,2,6-二氟苯胺价格较高,回收2,6-二氟苯胺是双氟磺草胺生产过程必要的环节。本文探索了一种2,6-二氟苯胺的回收方法,回收率96%以上,回收2,6-二氟苯胺质量分数95... 详细信息

2,6-二氟苯胺是合成双氟磺草胺的重要原料和溶剂,投料量是反应所需量的4~5倍,2,6-二氟苯胺价格较高,回收2,6-二氟苯胺是双氟磺草胺生产过程必要的环节。本文探索了一种2,6-二氟苯胺的回收方法,回收率96%以上,回收2,6-二氟苯胺质量分数95%。极大地降低了双氟磺草胺的生产成本,提高了产品的市场竞争力。

关键词：双氟磺草胺 2,6-二氟苯胺回收率成本

维普期刊数据库

Typical wheel–rail profile change rules and matching characteristics of high speed railway in China

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Railway Sciences 2022年第2期1卷 289-306页

作者： Maorui Hou fengshou liu Xiaoyi Hu Railway Science and Technology Research and Development Center China Academy of Railway Sciences Corporation LimitedBeijingChina Metals and Chemistry Research Institute China Academy of Railway Sciences Corporation LimitedBeijingChina

Purpose–In order to systematically grasp the changes and matching characteristics of wheel and rail profiles of high speed railway(HSR)in China,172 rail profile measurement points and 384 wheels of 6 high-speed electric motive unites(EMUs)were selected on 6 typical HSR lines,including Beijing–Shanghai,Wuhan–Guangzhou,Harbin–Dalian,Lanzhou–Xinjiang,Guiyang–Guangzhou and Dandong–Dalian for a two-year field test.Design/methodology/approach–Based on the measured data,the characteristics of rail and wheel wear were analyzed by mathematical statistics method.The equivalent conicity of wheel and rail matching in a wheel reprofiling cycle was analyzed by using the measured rail profile.Findings–Results showed that when the curve radius of HSR was larger than 2,495 m,the wear rate of straight line and curve rail was almost the same.For the line with annual traffic gross weight less than 11 Mt,the vertical wear of rail was less than 0.01 mm.The wear rate of the rail with the curve radius less than 800 m increased obviously.The wheel tread wear of EMUs on Harbin–Dalian line,Lanzhou–Xinjiang line and Dandong–Dalian line was relatively large,and the average wear rate of tread was about 0.05–0.06 mm$(10,000 km)1,while that of Beijing–Shanghai line,Wuhan–Guangzhou line and Guiyang–Guangzhou line was about 0.03–0.035 mm$(10,000 km)1.When the wear range was small,the equivalent conicity increased with the increase of wheel tread wear.When the wear range of wheel was wide,the wheel–rail contact points were evenly distributed,and the equivalent conicity did not increase obviously.Originality/value–This research proposes the distribution range of the equivalent conicity in one reprofiling cycle of various EMU trains,which provides guidance for the condition-based wheel reprofiling.

关键词： High speed railway(HSR) Typical railway line Rail wear Wheel wear Wheel–rail interface Equivalent conicity

Development of rail technology for high speed railway in China

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Railway Sciences 2023年第4期2卷 431-446页

作者： fengshou liu Guang Yang Zhaoyang Chen Yinhua Zhang Qingyue Zhou Metals and Chemistry Research Institute China Academy of Railway Sciences Corporation LimitedBeijingChina

Purpose–The purpose of this paper is to summarize the status and characteristics of rail technology of high-speed railway in China,and point out the development direction of rail technology of high-speed railway.Design/methodology/approach–This study reviews the evolution of high-speed rail standards in China,comparing their chemical composition,mechanical attributes and geometric specifications with EN standards.It delves into the status of rail production technology,shifts in key performance indicators and the quality characteristics of rails.The analysis further examines the interplay between wheels and rails,the implementation of grinding technology and the techniques for inspecting rail service conditions.It encapsulates the salient features of rail operation and maintenance within the high-speed railway ecosystem.The paper concludes with an insightful prognosis of high-speed railway technology development in China.Findings–The rail standards of high-speed railway in China are scientific and advanced,highly operational and in line with international standards.The quality and performance of rail in China have reached the world’s advanced level.The 60N profile guarantees the operation quality of wheel–rail interaction effectively.The rail grinding technology system scientifically guarantees the long-term good service performance of the rail.The rail service state detection technology is scientific and efficient.The rail technology will take“more intelligent”and“higher speed”as the development direction to meet the future needs of high-speed railway in China.Originality/value–The development direction of rail technology for high-speed railway in China is defined,which will promote the continuous innovation and breakthrough of rail technology.

关键词： High speed railway Rail Wheel–rail interaction Intelligent operation and maintenance

Aqueous controllable synthesis of spindle-like palladium nanoparticles and their application for catalytic reduction of 4-nitrophenol

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Progress in Natural Science:Materials International 2016年第5期26卷 295-302页

作者： Jie Li Bo Xu Guangning liu Guozhu Chen Tao Zhang fengshou Zhang Cuncheng Li School of Chemistry and Chemical Engineering University of Jinan

In this study, an effective wet-chemical route was developed in an aqueous solution for the synthesis of spindle-like palladium nanoparticles(Pd NPs). Spindle-like Pd NPs in high-yield were successfully synthesized by using cetyltrimethylammonium chloride(CTAC) as surfactant and ascorbic acid(AA) as reduction reagent. The influence factors including the concentration of CTAC, AA, and Na I, as well as the reaction temperature for synthesis of spindle-like Pd NPs were systematically investigated. The formation mechanism of spindle-like Pd NPs was proposed on the basis of these experimental results. Spindlelike Pd NPs with high density of twins and sharp edges exhibit enhanced catalytic activities for the reduction of 4-nitrophenol.

关键词： Palladium Catalyst Spindle-like nanoparticles