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Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： Peng SI Qing-Xiang LI Xiao-Yang CHEN Min WANG Chuan-Jun LUO Tianjin meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China shaoguan meteorological service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

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Mechanical properties of multi-scale germanium specimens from space solar cells under electron irradiation

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Chinese Journal of Aeronautics 2024年第1期37卷 173-185页

作者： Jian QIU Maliya HEINI Jusha MA Wenjia HAN Xunchun WANG Jun YIN Yan SHI Cunfa GAO State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Chemistry and Civil Engineering Shaoguan UniversityShaoguan 512005China Key Laboratory of Functional Materials and Devices for Special Environments of Chinese Academy of Sciences Chinese Academy of SciencesUrumqi 830011China Shanghai Institute of Space Power-Sources Shanghai 200245China

During long-term service in space,Gallium Arsenide(GaAs)solar cells are directly exposed to electron irradiation which usually causes a dramatic decrease in their *** the multilayer structure of solar cells,the germanium(Ge)layer occupies the majority of the thickness as the *** to the intrinsic brittleness of semiconductor material,there exist various defects during the preparation and assembly of solar cells,the influences of which tend to be intensified by the irradiation *** this work,first,Ge specimens for mechanical tests were prepared at scales from microscopic to ***,after different doses of electron irradiation,the mechanical properties of the Ge specimens were *** experimental results demonstrate that electron irradiation has an obvious effect on the mechanical property variation of Ge in diverse *** four-point bending test indicates that the elastic modulus,fracture strength,and maximum displacement of the Ge specimens all increase,and reach the maximum value at the irradiation dose of 1×10^(15)e/cm^(2).The micrometer scale cantilever and nanoindentation tests present similar trends for Ge specimens after *** Force Microscope(AFM)also observed the change in surface ***,a fitting model was established to characterize the relation between modulus change and electron irradiation dose.

关键词： Electron irradiation Germanium Mechanical properties Multi-scale Space solar cells

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A Task-oriented Approach to the Pre-service Teacher Education in the Classroom of English Teaching Methodology （ETM）

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Sino-US English Teaching 2006年第7期3卷 18-21,47页

作者： Hongyan Wu shaoguan College

This paper concerns itself with a task-oriented approach to the pre-service teacher education in the Classroom of English Teaching Methodology （ETM）. We attempt to use an explicit theoretic framework to guide the practice of ETM classroom in teacher education. The basic assumption is that we can use methodology which we use in teaching language, and apply those techniques and methods to train student teachers. By this approach the student teachers can adopt a research orientation to their own classrooms and their own teaching, an inquiry-based and discovery-oriented approach to learning is greatly emphasized, and they also can form the habit of generating theories and hypotheses and reflecting critically on teaching.

关键词： pre-service teacher education English teaching methodology task-oriented approachtask-design

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Fatigue Safety Assessment of Concrete Continuous Rigid Frame Bridge Based on Rain Flow Counting Method and Health Monitoring Data

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Journal of Architectural Environment & Structural Engineering Research 2023年第3期6卷 31-40页

作者： Yinghua Li Junyong He Xiaoqing Zeng Yanxing Tang Shixing County Administrative service Center ShixingShaoguanGuangdong512500China Guangdong College of Industry and Commerce GuangzhouGuangdong510510China Shixing County Statistics Bureau ShixingShaoguanGuangdong512500China Shixing County Hospital of Traditional Chinese Medicine ShixingShaoguanGuangdong512500China

The fatigue of concrete structures will gradually appear after being subjected to alternating loads for a long time,and the accidents caused by fatigue failure of bridge structures also appear from time to *** at the problem of degradation of long-span continuous rigid frame bridges due to fatigue and environmental effects,this paper suggests a method to analyze the fatigue degradation mechanism of this type of bridge,which combines long-term in-site monitoring data collected by the health monitoring system(HMS)and fatigue *** the paper,the authors mainly carry out the research work in the following aspects:First of all,a long-span continuous rigid frame bridge installed with HMS is used as an example,and a large amount of health monitoring data have been acquired,which can provide efficient information for fatigue in terms of equivalent stress range and cumulative number of stress cycles;next,for calculating the cumulative fatigue damage of the bridge structure,fatigue stress spectrum got by rain flow counting method,S-N curves and damage criteria are used for fatigue damage ***,it was considered a linear accumulation damage through the Palmgren-Miner rule for the counting of stress *** health monitoring data are adopted to obtain fatigue stress data and the rain flow counting method is used to count the amplitude varying fatigue *** proposed fatigue reliability approach in the paper can estimate the fatigue damage degree and its evolution law of bridge structures well,and also can help bridge engineers do the assessment of future service duration.

关键词： Long-span continuous rigid frame bridge Rain flow counting method Fatigue performance Health monitoring system Strain monitoring data

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Dynamic Reliability Assessment of Heavy Vehicle Crossing a Prototype Bridge Deck by Using Simulation Technology and Health Monitoring Data

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Journal of Architectural Environment & Structural Engineering Research 2022年第4期5卷 10-17页

作者： Yinghua Li Junyong He Xiaoqing Zeng Yanxing Tang Shixing County Administrative service Center ShixingShaoguanGuangdong512500China Guangdong College of Industry and Commerce No.1O98Guangzhou North RoadTianheGuangzhouGuangdongChina Shixing County Statistics Bureau ShixingShaoguanGuangdong512500China Shixing County Hospital of Traditional Chinese Medicine ShixingShaoguanGuangdong512500China

Overloads of vehicle may cause damage to bridge structures,and how to assess the safety influence of heavy vehicles crossing the prototype bridge is one of the *** this report,using a large amount of monitored data collected from the structural health monitoring system(SHMS)in service of the prototype bridge,of which the bridge type is large-span continuous rigid frame bridge,and adopting FEM simulation technique,we suggested a dynamic reliability assessment method in the report to assess the safety impact of heavy vehicles on the prototype bridge during *** the first place,by using the health monitored strain data,of which the selected monitored data time range is before the opening of traffic,the quasi dynamic reliability around the embedded sensor with no traffic load effects is obtained;then,with FEM technology,the FEM simulation model of one main span of the prototype bridge is built by using ANSYS software and then the dynamic reliability when the heavy vehicles crossing the prototype bridge corresponding to the middle-span web plate is comprehensively analyzed and *** last,assuming that the main beam stress state change is in the stage of approximately linear elasticity under heavy vehicle loads impact,the authors got the impact level of heavy vehicles effects on the dynamic reliability of the prototype *** on a large number of field measured data,the dynamic reliability value calculated by our proposed methodology is more *** method suggested in the paper can do good for not only the traffic management but also the damage analysis of bridges.

关键词： Large-span continuous rigid frame bridge Heavy vehicle Dynamic reliability evaluation SHM Finite element simulation technology

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Antibacterial and Alkali-responsive Cationic Waterborne Polyurethane Based on Modification of Aloe Emodin

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Chemical Research in Chinese Universities 2023年第2期39卷 266-275页

作者： XIONG Xiaoyan LI Xiaobin ZHU Zifan ZHANG Ending SHI Jun LU Mangeng Guangzhou Institute of Chemistry Chinese Academy of SciencesGuangzhou510650P.R.China University of Chinese Academy of Sciences Beijing100049China Guangdong Provincial Key Laboratory of Organic Polymer Materials for Electronics Guangzhou510650China New Materials Research Institute of CASCHEM(Chongqing)Co. Ltd.Chongqing400714China CASH GCC shaoguan Research Institute of Advanced Materials Shaoguan512440China

Cationic water-based polyurethane(CWPU)was synthesized to explore aloe-emodin modifies to obtain CWPU materials with better comprehensive *** provides a simple way to synthesize antibacterial waterborne polyurethane,which is to introduce the end-blocking group of herbal extracts into the *** contains synergistic antibacterial effect of herbal antibacterial and quaternary ammonium ion on Escherichia *** makes the material resist the erosion of bacterial,and increase the service life of *** the pH value of the environment changes,the UV absorbance of the aloe-emodin modified cationic water-based polyurethane(AE-CWPU)also ***,within a certain detection range,AE-CWPU has great applications in the field of smart response *** modified thermodynamic properties have been improved,and the mechanical properties basically maintained the maximum stress,and the elongation at break was reduced.

关键词： Waterborne polyurethane Aloe emodin Quaternary ammonium salt Antibacterial pH response

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Valuation on Forest Ecosystem services of Nanling National Nature Reserve

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Journal of Landscape Research 2017年第3期9卷 83-86,90页

作者： CHENG Zhiming LIAO Fangjun XIE Yong LIU Zongjun Nanling National Nature Reserve Administration ShaoguanGuangdong 512727China School of Life Sciences Sun Yat-Sen UniversityGuangzhouGuangdong 510275China

The forest ecological system fulfills many important ecological functions. Researches on the analysis and valuation on forest ecosystem services are at the cutting edge of current ecology and ecological economics. Based on the calculation method of service value of forest ecosystem, 7 forest ecosystem services of Nanling National Nature Reserve were valued, totaling 703.48 million yuan/year. In terms of the contribution size of the service value of forest ecosystem, carbon fixation and oxygen release came as the greatest one, followed by conservation of soil, purification of the air, biodiversity conservation, conservation of water, accumulation of nutrients, and forest recreation. With its value of 208.46 million yuan, carbon fixation and oxygen release ranked first, accounting for 29.63% of the total value; conservation of soil of 24.67% service value took the second place; purification of the air came in third in the value rankings, representing 22.55% of the total value; the fourth one was biodiversity conservation, whose service value came up to 14.51%. Those 4 services made up 91.36% of the total value while other 3 services ranging from conservation of water, accumulation of nutrients to forest recreation were merely a small proportion. This is because the Nanling National Nature Reserve is essentially a large oxygen bar. The above-mentioned ecosystem valuation method contributes to the understanding of the overall value of the forest ecosystem as well as the implementation and advancement in the regional sustainable development strategy.

关键词： Forest ecosystem service value Assessment Nanling Nature reserve

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Maintenance Management Research of a Large-span Continuous Rigid Frame Bridge Based on Reliability Assessment by Using Strain Monitored Data

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Journal of Architectural Environment & Structural Engineering Research 2021年第2期4卷 20-31页

作者： Yinghua Li Kesheng Peng Junyong He Qiangjun Shuai Gang Zou Shixing County Bureau of transportation Shixing CountyShaoguan CityGuangdong Province512500China HARDA(XIAMEN)PLASTIC CO. LTDNo.37Huili ZoneTongAn Industrial AreaXiamenChina Guangdong College of Industry and Commerce No.1O98Guangzhou North RoadTianhe DistrictGuangzhouChina 48-13B Baohe road 81Long Gang DistrictShenzhenGuangdongChina 54-28D Yi Jin YuanLong Cheng StreetLong Gang DistrictShenzhenGuangdongChina

When the bridge components needing maintenance are the world problem at present,and the health monitoring system is considered to be a very helpful tool for solving this *** this paper,a large number of strain data acquired from the structural health monitoring system(SHMS)installed on a continuous rigid frame bridge are adopted to do reliability ***,a calculation method of punctiform time-dependent reliability is proposed based on the basic reliability theory,and introduced how to calculate reliability of the bridge by using the stress data transformed from the strain ***,combined with“Three Sigma”principle and the basic pressure safety reserve requirement,the critical load effects distribution function of the bridge is defined,and then the maintenance reliability threshold for controlling the unfavorable load state which appears in the early operation stage of this type bridge is suggested,and then the combination of bridge maintenance management and health monitoring system is ***,the transformed stress distribution certifies that the load effects of concrete bridges practically have a normal distribution;as for the concrete continuous rigid frame bridge with C50 strength grade concrete,the retrofit reliability threshold should be valued at *** methodology suggested in this article can help bridge engineers do effective maintenance of bridges,which can effectively extend the service life of the bridge and bring better economic and social benefits.

关键词： Structural health monitoring Punctiform time-varying reliability Critical load effects distribution function Maintenance reliability threshold Continuous rigid frame bridge “Three Sigma”principle

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