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Geomorphometric Features of the Alluvial Fans around the Chaka-Qinghai lake in the Northeastern Tibetan Plateau

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Journal of Earth Science 2014年第1期25卷 109-116页

作者： Huiping Zhang yuanyuan lü State Key laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration Key laboratory of Saline lake Resources and Environment Institute of Mineral ResourcesChinese Academy of Geological Sciences

This article aims to study the geomorpometric features of alluvial fans since they act as a small-scale geomorphic unit response to tectonics and climate changes around the Chaka-Qinghai lake area in the northeastern Tibetan Plateau. We quantitatively extracted geomorphic parameters, such as the surface area and slope of alluvial fans adjacent to the Qinghai Nan Shan and Ela Shan. Alluvial fans in the Chaka lake partition area, south of the Qinghai Nan Shan, are featured by a small area and short length, but the largest slope. Geomorphic parameters of the alluvial fans in Ela Shan area are in- termediate in size, and the alluvial fans in the Qinghai lake partition area north of Qinghai Nan Shan have the gentlest slope. Together with the regional faulting activity analysis, we suggest that the alluvial fans with the high slopes in the south of Qinghai Nan Shan are mainly controlled by the reverse faulting along the Qinghai Nan Shan faults, and the strike-slip movement of the Eia Shan fault zone plays a weak role. In contrast, due to the lack of active faults, the alluvial fans near the Qinghai lake area north of the Qinghai Nan Shan only respond to regional erosion, transportation, and deposition proc- esses, thereby forming relatively gentle geomorphic units.

关键词： northeastern Tibetan Plateau Chaka-Qinghai lake alluvial fan geomorphometric fea- ture geomorphic process.

基于改进YOlOv5的轻量级黄花成熟检测方法

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中国农机化学报 2024年第7期45卷 235-242,268页

作者：吴利刚吕媛媛周倩陈乐张梁史建华山西大同大学机电工程学院山西大同037003 山西大同大学煤炭工程学院山西大同037003 山西大同大学商学院山西大同037003

黄花菜具有较短的采摘周期和相对严格的采摘要求,针对传统人工采摘效率低、主观性高的问题,提出一种基于深度学习的SSH-YOlOv5黄花成熟度检测算法。以YOlOv5模型为基础,结合轻量级网络ShuffleNet V2基本残差单元压缩网络模型大小,提升... 详细信息

黄花菜具有较短的采摘周期和相对严格的采摘要求,针对传统人工采摘效率低、主观性高的问题,提出一种基于深度学习的SSH-YOlOv5黄花成熟度检测算法。以YOlOv5模型为基础,结合轻量级网络ShuffleNet V2基本残差单元压缩网络模型大小,提升模型目标检测速度;引入SE Net通道注意力机制模块,增强模型对有用特征信息的敏感度,提高目标检测精度;将普通卷积替换为深度可分离卷积模块,进一步减少模型计算量。试验结果表明,改进后的SSH-YOlOv5模型参数量和浮点运算量分别减少61.6%和68.3%,网络层数减少18%,同时SSH-YOlOv5的检测精度由原算法的88.8%提高到91.2%,实时检测速度达到66.4 f/s,相比原算法提高18.1%,达到实时检测要求。改进后的算法不仅实现模型的轻量化,同时也使黄花成熟度检测更加准确和快速,可以较好地满足黄花检测需求。

关键词：黄花深度学习 YOlOv5算法轻量化注意力机制

Origin of Halite in the lanping–Simao Basin,Southeastern Tibetan Plateau,China:Evidence from Sr and Cl Isotopes

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2028-2039页

作者： DU Shaorong ZHENG Mianping lÜyuanyuan ZHANG Yongsheng ZHANG Xuefei MIAO Zhongying lI Mingming MlR Key laboratory of Saline lake Resources and Environments Institute of Mineral ResourcesChinese Academy of Geological Sciences(CAGS)Beijing 100037China College of Geoscience and Surveying Engineering China University of Mining and Technology(Beijing)Beijing 100083China

The lanping−Simao Basin is located on the southeastern Tibetan Plateau,China,and contains massive *** origin of evaporites in the basin has been hotly debated because of the strong transformation by tectonic *** halite samples from borehole MK-3 in the Mengyejing area of the basin were collected and analyzed using XRD,Cl-Sr isotopes and chemical compositions to trace the origin of the evaporites in the *** Br×10^(3)/Cl ratios of the halite samples are between 0 and 0.55,most of which are synchronized with the law of seawater evaporation and at the stage of halite precipitation from seawater,indicating that the evaporites are mainly of marine ***^(87)Sr/^(86)Sr ratios range from 0.707489 to 0.711279;after correction,the^(87)Sr/^(86)Sr 145 Ma ratios range from 0.704721 to 0.707611,equivalent with the 87Sr/86Sr ratios of seawater at 145 Ma,indicating a marine *** decay of 87Rb in the evaporite during deposition,change of the depositional environment and the unsealed environment at a later period resulted in the present^(87)Sr/^(86)Sr ratios of some samples being *** δ^(37)Cl value compositions range from−0.38‰to 0.83‰,which is consistent with the δ^(37)Cl value composition of the world marine halite(−0.6‰to 0.4‰),further confirming that seawater is the main *** addition,the high δ^(37)Cl value of some samples at the boundary of the upper and lower evaporite layers might be related to the influence of δ^(37)Cl-rich brine and the incomplete dissolution of the halite.

关键词： evaporites halite potash Cl-Sr isotopes lanping-Simao Basin

Geochemical processes and origin of boron isotopes in geothermal water in the Yunnan-Tibet geothermal zone

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Science China Earth Sciences 2014年第9期57卷 2934-2944页

作者： lü yuanyuan ZHENG MianPing ZHAO Ping XU RongHua MlR Key laboratory of Saline lake Resources and Environments Institute of Mineral Resources Chinese Academy of Geological Sciences Institute of Tibetan Plateau Research Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

Boron concentrations and isotope compositions have been measured for 93 water samples from the hot springs and drill-holes in the geothermal system in the Yunnan-Tibet Geothermal Belt(YTGB),*** concentrations range from 0.036–472.4ppm,and theδ11B values range from -16.0‰to 13.1‰,indicating the non-marine origin for each geothermal *** observed a clear binary mixing relationship between the B concentrations and B isotope compositions in Tibet geothermal *** relationship can be well explained by two sources,i.e.,marine carbonate rocks and magmatic rocks,for the Tibet geothermal *** evidence supports a mantle contribution to *** addition,we found that the precipitation only plays a dilution role for B of geothermal waters.δ11B values for the precipitation across the southern Tibetan Plateau area range from -6.0‰ to -6.8‰at *** to data scarcity in Yunnan geothermal area,we observed possible different boron sources from the Tibet geothermal *** it with other geothermal systems in the world,we found that the samples from YTGB have the lowestδ11B values and the largest range of B concentration,which might be related to their special geological *** the whole,the world geothermalδ11B-Cl/B relation suggests a mixing process between marine and non-marine ***,we suggest that B source of B-enriched geothermal waters is mainly from B-enriched crustal country-rocks,instead of mantle.

关键词： Yunnan-Tibet geothermal zone Boron isotope geothermal water tracing

Heat Storage Performance of PCM in a Novel Vertical Pointer-Shaped Finned latent Heat Tank

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Journal of Thermal Science 2024年第2期33卷 422-434页

作者： MAO Qianjun ZHU yuanyuan lI Tao School of Urban Construction Wuhan University of Science and TechnologyWuhan430065China

The heat storage performance of latent heat storage systems is not good due to the poor thermal conductivity of phase change *** this paper,a new type of pointer-shaped fins combining rectangular and triangular fins has been employed to numerically simulate the melting process in the heat storage tank,and the fin geometry parameter effects on heat storage performance have been *** results indicate that compared with the bare tube and the rectangular finned tank,the melting time of the phase change material in the pointer-shaped finned tank is reduced by 64.2%and 15.1%,*** closer the tip of the triangular fin is to the hot wall,the better the heat transfer *** optimal height of the triangular fin is about 8 *** the number of fins from 4 to 6 and from 6 to 8 reduces the melting time by 16.0%and 16.7%***,increasing the number of fins from 8 to 10 only reduces the melting time by 8.4%.When the fin dimensionless length is increased from 0.3 to 0.5 and from 0.5 to 0.7,the melting time is shortened by 17.5%and 13.0%.But the melting time is only reduced by 2.9%when the dimensionless fin length is increased from 0.7 to *** optimising the design of the thermal storage system,the results can provide a reference value.

关键词： thermal energy storage phase change material pointer-shaped fins heat storage performance

Developing a novel quantitative parameter for characterizing spatial distribution of fish following exposure to chemicals and wastewater:Behavioral Gini coefficient

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Journal of Environmental Sciences 2024年第7期141卷 129-138页

作者： Xuanyue Chen yuanyuan li Zhanfen Qin State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

While the spatial distribution pattern of fish is increasingly used for toxicological test o chemicals or wastewater,no ideal parameter is available for quantitative assessment of spa tial distribution,especially uneven distribution with multiple ***,to develop a quantitative assessment parameter for spatial distribution,the zebrafish were exposed to ethanol,pentylenetetrazole(PTZ),paraquat dichloride(paraquat)and wastewater,followed by a behavioral test in a narrow *** data was acquired and analyzed by id Tracker and *** comparing the effects of all treatments on behavior parameters we confirmed that the spatial distribution was more easily altered rather than general loco motor parameters,e.g.0.7-70 mg/l PTZ and 5-20 mg/l paraquat being effective for altering spatial distribution but having little effects on general locomotor *** on the heatmap,i.e.,the cumulative proportion of grids and that of frequency in grids,we calcu lated the behavioral Gini coefficient(G_(b))for quantitative assessment of fish spatial distri *** Gini coefficient ranged from zero to 1,with larger values meaning poorer even ness of spatial *** note,G_(b)showed smaller coefficient of variations(CV)with3%-19%between replicate tanks in all treatments than the highest frequency(4%-79%),dis playing well ***,G_(b)addressed the challenge of the complicated heatmap with multiple ***,the behavioral Gini coefficient we established is an idea parameter to quantitatively assess spatial distribution of fish shoal,which is expected to be applied in toxicity testing for chemicals and wastewater and automatic quality monitoring for surface water and aquaculture water.

关键词： Zebrafish Behavioral test Spatial distribution Behavioral Gini coefficient

Design Optimization and Operating Performance of S-CO_(2) Brayton Cycle under Fluctuating Ambient Temperature and Diverse Power Demand Scenarios

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Journal of Thermal Science 2024年第1期33卷 190-206页

作者： YANG Jingze YANG Zhen DUAN yuanyuan Key laboratory for Thermal Science and Power Engineering of MOE Beijing Key Laboratory for CO_(2) Utilization and Reduction TechnologyTsinghua UniversityBeijing 100084China

The supercritical CO_(2)(S-CO_(2)) Brayton cycle is expected to replace steam cycle in the application of solar power tower system due to the attractive potential to improve efficiency and reduce *** the concentrated solar power plant with thermal energy storage is usually located in drought area and used to provide a dispatchable power output,the S-CO_(2) Brayton cycle has to operate under fluctuating ambient temperature and diverse power demand *** addition,the cycle design condition will directly affect the off-design *** this work,the combined effects of design condition,and distributions of ambient temperature and power demand on the cycle operating performance are analyzed,and the off-design performance maps are proposed for the first time.A cycle design method with feedback mechanism of operating performance under varied ambient temperature and power demand is introduced *** show that the low design value of compressor inlet temperature is not conductive to efficient operation under low loads and sufficient output under high ambient *** average yearly efficiency is most affected by the average power demand,while the load cover factor is significantly influenced by the average ambient *** multi-objective optimization,the optimal solution of designed compressor inlet temperature is close to the minimum value of35℃ in Delingha with low ambient temperature,while reaches 44.15℃ in Daggett under the scenario of high ambient temperature,low average power demand,long duration and large value of peak load during the peak temperature *** the cycle designed with compressor inlet temperature of 35℃ instead of 44.15℃ in Daggett under light industry power demand,the reduction of load cover factor will reach 0.027,but the average yearly efficiency can barely be improved.

关键词： supercritical CO_(2)Brayton cycle ambient temperature fluctuating power demand scenarios design optimization off-design performance

Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020

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Chinese Geographical Science 2024年第1期34卷 181-194页

作者： ZHU yuanyuan ZHANG Yan ZHU Xiaohua Key laboratory of Geographic Process Analysis&Simulation Hubei Province Central China Normal UniversityWuhan430079China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China

Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important *** study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary *** results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption *** dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality *** the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing *** per capita food carbon emissions of residents in urban and rural showed an overall upward *** total food carbon emissions in urban increased significantly,while that in rural increased first and then *** influence of beef and mutton on carbon emissions is the highest in dietary *** with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern.

关键词： dietary structure structural evolution carbon emission effects carbon neutrality China

Pressure-Induced Pre-lithiation Enables High-Performing Si Anodes in All-Solid-State Batteries

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Energy & Environmental Materials 2024年第6期7卷 1-3页

作者： Weifei Hu yuanyuan li Jinping liu School of Chemistry Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China

A commentary on pressure-induced pre-lithiation towards Si anodes in allsolid-state li-ion batteries(ASSlIBs)using sulfide electrolytes(SEs)is ***,feasible pre-lithiation technologies for Si anodes in SE-based ASSlIBs especially the significant pressure-induced pre-lithiation strategies are briefly ***,a recent achievement by Meng et *** this field is elaborated in ***,the significance of Meng’s work is discussed.

关键词： all-solid-state li-ion batteries pre-lithiation pressure Si anode sulfide electrolyte