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Algorithm for cavity flow in a new-born goaf and experimental verification

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International Journal of Mining Science and Technology 2023年第3期33卷 351-361页

作者： Jian Liu qichao zhou Dong Wang Lijun Deng Ke Gao College of Safety Science&Engineering Liaoning Technical UniversityHuludao 125105China Key Laboratory of Mine Thermo-motive Disaster&Prevention Ministry of EducationHuludao 125105China

Prevention and control measures of spontaneous combustion of coal and gas accumulation in a goaf require an accurate description of its gas flow ***,the commonly used fluid dynamics in porous media is not suitable for the new-born goaf with fracture cavity combination,multi-scale,and large *** this study,we propose a cavity flow algorithm to accurately describe the gas flow state in the new-born *** genetic algorithm(GA)is used to randomly generate the binary matrix of a goaf caving *** difference between the gas flow state calculated by the lattice Boltzmann method(LBM)and the measured data at the boundary or internal measuring points of the real goaf is taken as the GA fitness value,and the real goaf caving shape and the gas flow state are quickly addressed by *** experimental model of new-born goaf is established,and the laser Doppler anemometry(LDA)experiment is carried *** results show that the Jaccard similarity coefficient between the reconstructed caving shape and the real caving shape is 0.7473,the mean square error between the calculated wind speed and the LDA-measured value is 0.0244,and the R2 coefficient is 0.8986,which verify the feasibility of the algorithm.

关键词： Cavity flow Lattice Boltzmann method Laser Doppler anemometry New-born goaf Genetic algorithm

Total nitrogen and community turnover determine phosphorus use efficiency of phytoplankton along nutrient gradients in plateau lakes

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Journal of Environmental Sciences 2023年第2期124卷 699-711页

作者： Yun Zhang Hucai Zhang Qi Liu Lizeng Duan qichao zhou Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental SciencesYunnan UniversityKunming 650500China

Numerous studies support that biodiversity predict most to ecosystem functioning,but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be *** investigated 398 samples of the phytoplankton phosphorus resource use efficiency(RUE_(P)=chlorophyll-a concentration/dissolved phosphate)across two seasons in nine plateau lakes in Yunnan Province,*** identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic *** results showed that total nitrogen(TN)contributed the most to RUEP among the nine lakes,whereas community turnover(measured as community dissimilarity)explained the most to RUEP variation across the two ***,TN also influenced RUEP by affecting *** richness(SR),functional attribute diversity(FAD2),and dendrogram-based functional diversity(FDc)were positively correlated with RUEP in both seasons,while evenness was negatively correlated with RUEP at the end of the rainy *** also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic *** and FAD2 were positively correlated with RUEP in all three trophic *** showed a negative correlation with RUEP at the eutrophic and oligotrophic levels,but a positive correlation at themesotrophic *** had a negative influence on RUEP at the eutrophic level,but a positive influence at the mesotrophic and oligotrophic ***,our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversityecosystem functioning relationships are investigated.

关键词： Community turnover Biodiversity Phytoplankton Resource use efficiency Taxonomic diversity Total nitrogen

基于鲸鱼算法的配电网无功补偿经济性优化配置方法

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电工技术 2024年第9期 91-94页

作者：李青杉陈星郑杰周祺超胡谦国网浙江省电力有限公司衢州供电公司浙江衢州324000

无功优化需对配电网的无功补偿选址与容量设定进行合理配置。提出了基于鲸鱼算法的配电网无功补偿经济性优化配置方法,根据功率损失系数确定无功补偿的优选节点,并利用鲸鱼优化算法解出符合经济性与配电网运行规则的无功补偿设备最优接... 详细信息

无功优化需对配电网的无功补偿选址与容量设定进行合理配置。提出了基于鲸鱼算法的配电网无功补偿经济性优化配置方法,根据功率损失系数确定无功补偿的优选节点,并利用鲸鱼优化算法解出符合经济性与配电网运行规则的无功补偿设备最优接入节点位置与容量。以IEEE 33节点配电网系统为模型进行的仿真模拟表明,该方法能缩短计算时间、提高系统无功补偿效率。

关键词：无功补偿功率损失指数鲸鱼优化算法

昌平地震台井水位观测资料质量评价与数据分析

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地震地磁观测与研究 2024年第1期45卷 118-125页

作者：蒋雨函高小其刘福生周启超汪倩彭莱应急管理部国家自然灾害防治研究院北京100085 中国科学院大学北京100049

对2002—2023年昌平地震台地下流体数字化井水位观测资料进行系统整理,对数据的连续率、完整率、内在质量进行评估,同时,对水位资料的长期动态变化等进行了分析。结果表明,昌平地震台井水位观测资料连续、可靠,观测仪器稳定。井水位日... 详细信息

对2002—2023年昌平地震台地下流体数字化井水位观测资料进行系统整理,对数据的连续率、完整率、内在质量进行评估,同时,对水位资料的长期动态变化等进行了分析。结果表明,昌平地震台井水位观测资料连续、可靠,观测仪器稳定。井水位日变特征明显,具有清晰的固体潮效应,长期动态特征与昌平区地下水位动态特征一致,主要受到农业灌溉用水及水库生态补水的影响。井水位与气压间具有明显的负相关性,此外,井水位经一阶差分处理后的变化速率曲线与地震间具有相关性。

关键词：数字化观测井水位内在质量动态特征气压效应

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昌平地震台钻孔应变观测数据质量分析

地震地磁观测与研究 2024年第2期45卷 90-100页

作者：周启超郭贵娟蒋雨函高小其汪倩彭莱中国科学院大学应急管理科学与工程学院中国北京100049 应急管理部国家自然灾害防治研究院地壳动力学重点实验室中国北京100085 地震出版社中国北京100195

昌平地震台钻孔应变测项多年来积累了大量观测数据。采用调和分析及相对标定等方法,从观测数据连续率、稳定性等方面评估观测数据质量,并分析不同钻孔应变仪器的映震能力。结果表明:该台钻孔应变在运行测项稳定、可靠,在一定时间内观测... 详细信息

昌平地震台钻孔应变测项多年来积累了大量观测数据。采用调和分析及相对标定等方法,从观测数据连续率、稳定性等方面评估观测数据质量,并分析不同钻孔应变仪器的映震能力。结果表明:该台钻孔应变在运行测项稳定、可靠,在一定时间内观测资料质量整体较好。选取震中距300 km范围内历史典型震例进行分析,发现该台站体应变在华北地区多次5级以上地震前具有明显趋势异常,分量应变仪多次记录到临震异常。分析认为,昌平地震台钻孔应变观测资料能够反映其所在区域的构造活动和应变状态,可以为地震监测与研究提供可靠的基础数据。

关键词：昌平地震台钻孔应变观测数据质量评估映震能力

Influence of sunlight on the proliferation of cyanobacterial blooms and its potential applications in Lake Taihu, China

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Journal of Environmental Sciences 2014年第3期26卷 626-635页

作者： qichao zhou Wei Chen Kun Shan Lingling Zheng Lirong Song State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of Chinese Academy of Sciences

To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the natural light intensities with different shading ratio （0% （full sunlight）, 10%, 25%, 50% and 75% of original natural sunlight intensities） from September to November in 2010. The results indicated that phytoplankton biomass （mean） decreased significantly when the shading ratios reached 50% or more. Higher shading ratios （e.g. 75%） were very efficient in controlling the average and total cyanobacterialbloom biomass, while 50% shading ratio was proven very effective either in controlling the peak value of phytoplankton biomass or postponing the occurrence of cyanobacterial blooms in Lake Talhu. In addition, phytoplankton composition and photosynthesis efficiency were also affected by altering the shading ratios, and in turn, they might also act on phytoplankton growth. Based on the results from the present study, intermediate shading strategies such as regulation of water level or turbidity through the hydrology regulations would probably be an effective and efficient method in controlling cyanobacterial blooms in large and shallow lakes.

关键词： light cyanobacterial bloomscontrol Lake Taihu enclosure experiment

Simultaneous elimination of cyanotoxins and PCBs via mechanical collection of cyanobacterial blooms:An application of“green-bioadsorption concept”

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Journal of Environmental Sciences 2017年第7期29卷 118-126页

作者： Wei Chen Yunlu Jia Anyue Liu qichao zhou Lirong Song State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyThe Chinese Academy of SciencesWuhan 430072China University of Chinese Academy of Science Beijing 100049China

In this study,the distribution,transfer and fate of both polychlorinated biphenyls（PCBs）and cyanotoxins via phytoplankton routes were systematically investigated in two Chinese *** indicated that PCB adsorption/bioaccumulation dynamics has significantly positive correlations with the biomass of green alga and *** lipid content of phytoplankton is the major factor that influences PCB adsorption/*** blooms with relatively lower lipid content could also absorb high amount of PCBs due to their high cell density in the water columns,and this process was proposed as major route for the transfer of PCBs in Chinese eutrophic *** to these findings,a novel route on fates of PCBs via phytoplankton and a green bioadsorption concept were proposed and *** the practice of mechanical collections of bloom biomass from Lake Taihu,cyanotoxin/cyanobacteria and PCBs were found to be removed simultaneously very efficiently followed this theory.

关键词： Mechanical collection Cyanobacterial bloom PCBs Cyanotoxin Fate Green bioadsorption concept

Seasonal and spatial distributions of euphotic zone and longterm variations in water transparency in a clear oligotrophic Lake Fuxian, China

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Journal of Environmental Sciences 2018年第10期30卷 185-197页

作者： qichao zhou Yunlin Zhang Kaidi Li Licheng Huang Fengle Yang Yuanyang zhou Junjun Chang Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed Yunnan Institute of Environmental Science(Kunming China International Research Center for Plateau Lake) School of Ecology and Environmental Science Yunnan University

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth（Z（eu）） across the four seasons, and no significant correlations between Z（eu） and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Z（eu）in general. Nevertheless, significant differences in Z（eu） between the north region（NR） and the south region（SR） were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter（CDOM） in the NR due to runoff, especially in the rainy seasons（summer and autumn）.CDOM and its terrigenous component had an important impact on Z（eu）in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years,with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants（CDOM and/or phytoplankton） are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.

关键词： Photosynthetic active radiation Diffuse attenuation coefficient Euphotic depth Secchi disk depth Chromophoric dissolved organic matter Yunnan-Guizhou Plateau

Constitutive Relationship and Hot Processing Maps of Mg-Gd-Y-Nb-Zr Alloy

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Journal of Materials Science & Technology 2017年第7期33卷 637-644页

作者： Zhaohui zhou qichao Fan Zhihui Xia Aiguo Hao Wenhua Yang Wei Ji Haiqiao Cao Institute of Machinery Manufacturing Technology Chinese Academy of Engineering Physics Mianyang 621900 China

The hot working behavior of Mg-Gd-Y-Nb-Zr alloy was investigated using constitutive model and hot processing maps in this work. Isothermal compression tests were conducted with temperature and strain rate range of 703-773 K and 0.01-5 s^（-1）, respectively. Improved Arrhenius-type equation incorporated with strain compensations was used to predict flow behavior of the alloy, and the predictability was evaluated using correlation coefficient, root mean square error and absolute relative error. Processing maps were constructed at different strains for Mg-Gd-Y-Nb-Zr alloy based on dynamic materials *** processing maps are divided into three domains and the corresponding microstructure evolutions are referred to the forming of straight grain boundaries, twinning, dynamic recrystallization and grain growth. Instability occurred mainly at the strain rate range of 0.3s^（-1）-0.5s^（-1）. The optimum processing domain is mainly at the temperature range of 703-765 K with the strain rate range of 0.01-0.1 s^（-1）.

关键词： Magnesium alloy Recrystallization Constitutive model Processing maps Hot deformation