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The Middle and Late Holocene climate change in Bohai Bay revealed by diatom proxy

Journal of Oceanology and Limnology 2024年第5期42卷 1493-1506页

作者： Zhiwen shang Jianfen LI Fu wang Hong wang Tianjin Centre China Geological SurveyTianjin 300170China Key Laboratory of Coastal Geo-environment China Geological SurveyTianjin 300170China Tianjin Key Laboratory of Coast Geological Processes and Environmental Safety Tianjin 300170China

A total of 98 samples from two boreholes in shallow sea area and two oyster reefs in adjacent coastal plain in the northwestern coast of Bohai Bay were collected for diatom analyses and species *** ratio of the marine species Thalassionema nitzschioides to the intertidal-coastal species complex Cyclotella striata/stylorum serves as a novel proxy for assessing the strength of marine *** data,corrected for the local residence time effect,facilitated the construction of a diatom proxy-based marine influence curve for the study *** curve delineates the dynamics of marine influence and their correlations with paleo-climate fluctuations and the East Asian monsoon variability,as well as their role in chenier *** include:(1)eight periods of intensified marine influence have been documented since 7000 a BP in the study *** peak of each period,as determined by the diatom proxy,corresponds closely to the warm climatic phases and stronger East Asian summer monsoons,suggesting that the peaks marine influence indicate typically the periods of climatic warmth and monsoon activity intensification in the region;(2)a strong correlation exists between the development of cheniers and marine influence,and chenier formation began with the increasing marine influence and terminated at the end of warm periods as marine influence *** climatic changes in the coastal area,as indicated by the diatom proxy,hold significant potential for future related research endeavors.

关键词： Bohai Bay diatom diatom-based marine influence curve paleo-climate Holocene

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光谱卫星LPPT-25微电推进系统飞行试验工作性能评价

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真空 2024年第5期61卷 80-89页

作者：田立成王尚民陈昶文兰州空间技术物理研究所真空技术与物理重点实验室甘肃兰州730000

基于光谱卫星任务需求,兰州空间技术物理研究所开展了脉冲等离子体微电推进系统方案设计,以此完成25W级脉冲等离子体电推进系统飞行样机研制,并开展了地面各项测试,均满足需求。为了进一步验证该系统的空间环境适应性、与航天器的相互... 详细信息

基于光谱卫星任务需求,兰州空间技术物理研究所开展了脉冲等离子体微电推进系统方案设计,以此完成25W级脉冲等离子体电推进系统飞行样机研制,并开展了地面各项测试,均满足需求。为了进一步验证该系统的空间环境适应性、与航天器的相互兼容性、空间工作特性及空间飞行性能与地面数据的差异性,LPPT-25微电推进系统搭载长光卫星公司光谱星一号(GP-1)卫星开展了在轨飞行试验,对脉冲等离子体电推进系统在轨飞行试验结果进行了评价。结果表明:在整个飞行试验期间,脉冲等离子体电推进系统各项工作性能参数符合设计指标要求,电推进分系统工作正常,推力输出稳定,各遥测温度满足推进要求的控温范围;电推进推力标定为306.3μN,相比地面测试推力300μN,偏差在5%以内,体现了良好的天地一致性。

关键词： PPT推力器微电推进系统微小卫星姿态控制和轨道维持

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鲁北平原区洪水预报方案编制工作探讨

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海河水利 2024年第9期 38-40,49页

作者：宗雪纯宗先国王商羽滨州市水利勘测设计研究院有限责任公司山东滨州256600 滨州市水文中心山东滨州256600

洪水预报方案是预测洪水运行情况的基本依据。以鲁北平原区徒骇河堡集闸水文站为例,从预报方案编制依据及方法、编制内容及主要步骤、上下游洪峰流量相关预报、特殊洪水分析等方面介绍了堡集闸水文站洪水预报方案编制工作。以堡集闸“10... 详细信息

洪水预报方案是预测洪水运行情况的基本依据。以鲁北平原区徒骇河堡集闸水文站为例,从预报方案编制依据及方法、编制内容及主要步骤、上下游洪峰流量相关预报、特殊洪水分析等方面介绍了堡集闸水文站洪水预报方案编制工作。以堡集闸“10·08洪水”为例,从雨水情、水文预报和注意事项等方面对预报方案应用案例进行了深入分析,同时从方案修订、提高预报精度等方面对预报方案编制进行了初步探讨。本研究成果可为鲁北平原区河流洪水预报方案编制工作提供参考。

关键词：鲁北平原区洪水预报方案作业预报实时校正

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Energy-Function Based Pilot Protection Scheme for Hybrid UHVDC Transmission Applying Improved Hausdorff Distance

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 891-902页

作者： Zijiang wang Youping Fan Ben shang Yinbiao Shu School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Institute of Next Generation Power Systems&International Standards Wuhan UniversityWuhan 430072China CSEE IEEE

A hybrid UHVDC transmission system applying LCC as the rectifier and MMC as the inverter combines the advantages of both converter types,which makes this protection scheme more complicated.A new pilot protection scheme for a three-terminal hybrid DC transmission system applying energy functions is *** energy function for LCC is applied to MMC to derive the energy level of the hybrid ***,an improved Hausdorff distance(IHD)algorithm is proposed to detect the difference in energy levels between the normal and fault *** abrupt change in energy level is characterized by IHD change *** points at which the IHD change rate exceeds the threshold at converter stations are applied to determine the fault line and to estimate the fault *** proposed protection scheme is then verified by a simulation model of the Wudongde±800 kV three-terminal hybrid UHVDC transmission *** appropriate sampling frequency is selected for a real-time calculation,and the threshold is selected considering the effect of *** show the proposed scheme can identify and trip fault lines quickly and effectively,even for a 600Ωgrounding *** waveshape similarity algorithms are compared and *** with existing protection schemes,the proposed scheme transmits less data to improve communication speed and reliability.

关键词： Energy function Hausdorff distance pilot protection UHVDC transmission

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Pollen development and floral morphology of Populus pseudo-simonii

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Forestry Studies in China 2009年第2期11卷 99-104页

作者： wang Jun KANG xiang-yang WEI Qiang wang shang-de National Engineering Laboratory of Forest Genetics and Tree Breeding Beijing Forestry University Beijing 100083 P. R. China Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of Education Beijing Forestry University Beijing 100083 P. R. China Institute of Integrative Agricultural Development Beijing Academy of Agricultural and Forestry Sciences Beijing 100089 P. R. China

Pollen development and floral morphology of Populus pseudo-simonii were investigated by stain-squashing and anatomical techniques. It took approximately 16 days for the pollen to develop from pollen mother cells to mature pollen in the green-house. Meiosis of pollen mother cells was regularly applied and completed by a process of simultaneous cytokinesis. Pollen development was considerably asynchronous. The meiotic division was initiated at the bulgy middle position of the flower bud and proceeded towards the tip and base of the bud. The number and size of the nucleoli varied during pollen development and at most eight nucleoli formed in each daughter nucleus at the meiotic telophase, suggesting a paleopolyploid origin of the genus Populus. An association between floral morphology and pollen development was found and the ratio of width to length of flower buds or catkins presented an S-shaped curve related to pollen development as a function of time. The investigation on the pollen development and floral morphology ofP. pseudo-simonii is important for further cross breeding programs of the section Tacamahaca.

关键词： floral morphology meiosis microgametogenesis nucleolus pollen Populus pseudo-simonii

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Modeling of Rectangular Microchannel Heat Sink with Non-Uniform Channels and Multi-Objective Optimization

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Journal of Thermal Science 2024年第5期33卷 1701-1711页

作者： shang Xueshuo wang Yixin LI Qingwen wang Rui CUI Zheng SHAO Wei Institute of Advanced Technology Shandong UniversityJi'nan 250014China Institute of Thermal Science and Technology Shandong UniversityJi'nan 250014China Shandong Institute of Advanced Technology Ji'nan 250100China

Rectangular microchannel heat sinks(MCHS)are widely used to cool high-heat-flux electronic ***,previous studies focused mainly on MCHS with uniform channels(UCs).This study considers a microchannel heat sink with non-uniform channels(NUCs).A mathematical model is developed based on energy equations and the Darcy flow *** expressions for total thermal resistance and coolant pressure drop are derived using the thermoelectric *** and numerical simulations are performed to verify the mathematical *** non-uniformity increases,total coolant pressure drop decreases but at the cost of higher thermal *** overall performance of NUCs is better than that of UCs because of their lower ratio of pumping power to cooling *** transfer performance of NUCs changes little for more than 120 channels and depends mainly on channel arrangement.A multi-objective optimization is conducted to minimize the thermal resistance and pumping power of an *** optimal NUC saves 64%pumping power compared with a conventional UC for the total thermal resistance of 0.1℃/W,indicating that the use of non-uniform channels could be very helpful to reduce the flow resistance of MCHS.

关键词： microchannel heat sink non-uniform channel mathematical model multi-objective optimization

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Arterial and venous thromboembolism risk associated with blood eosinophils: A systematic review and meta-analysis

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Animal Models and Experimental Medicine 2022年第5期5卷 470-481页

作者： Wei-Jie Xu shang wang Ping Yuan Lan wang Jun-Xia Huang Rong Jiang Department of Clinical Laboratory Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Cardio-Pulmonary Circulation Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Department of Hematology Affiliated Hospital of Qingdao UniversityQingdaoShandongChina

The association between blood eosinophil(EOS)counts and arterial/venous throm-bosis is *** aim to explore whether EOS count is a risk factor for *** searched several databases and preprint platforms using core terms‘eosinophil’,‘myocardial infarction’,‘ischemic stroke’,and‘venous thromboembo-lism’(VTE),among *** comparing the odds ratios(ORs)or risk ratios(RRs)of EOSs with the abovementioned diseases were ***,22 studies were included.A high EOS count was associated with acute coronary artery throm-bosis events(OR:1.23,95%CI:1.15-1.32),short-term cerebral infarction and mor-tality(RR:2.87,95%CI:1.49-5.51).The short-term risk of VTE was more common in patients with EOS-related diseases(RR:6.52,95%CI:2.42-17.54).For coronary artery disease,a high EOS count was a protective factor against 6-month to 1-year mortality(RR:0.56,95%CI:0.45-0.69)but was associated with long-term mortal-ity(RR:1.64,95%CI:1.25-2.14).Therefore,we conclude that for coronary artery thrombosis,EOS count is not associated with AMI events in general *** may be associated with NSTEMI and STEMI in CAD patients,but more studies are needed to confirm *** addition,EOS count is associated with an increased risk of both short-and long-term mortality but is not predictive of the composite *** cerebral artery thrombosis,EOS count may be associated with cerebral infarction and could lead to an increased risk of poor short-term *** VTEs,EOS count was a risk factor for some patients,especially those with acute-phase EOS-related diseases.

关键词： eosinophil ischemic stroke myocardial infarction pulmonary embolism thrombosis

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Carbonation of Pure Minerals in Portland Cement:Evolution in Products as a Function of Water-to-solid Ratio

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1214-1222页

作者： XIONG Kun shang Xiaopeng LI Hongyan wang Dan Zhengzhou Lutong Highway Construction Co. Ltd.Zhengzhou 450052China (Special Glass Key Lab of Hainan Province)&(State Key Laboratory of Marine Resource Utilization in South China Sea) Hainan UniversityHaikou 570228China Department of Architectural Engineering Shandong Urban Construction Vocational CollegeJinan 250103China (State Key Laboratory of High Performance Civil Engineering Materials Jiangsu Sobute New Materials Co.Ltd.)&(School of Material Science and EngineeringSoutheast UniversityNanjing 211189China)

Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and product evolution for CO_(2)curing at various water-to-solid *** pure minerals were synthesized and subject to CO_(2)curing in this study to make an in-depth understanding for the carbonation properties of cement-based *** showed that the optimum water-to-solid ratios of C_(3)S,β-C_(2)S,C_(3)A and C_(4)AF were 0.25,0.15,0.30 and 0.40 for carbonation,corresponding to 2 h carbonation degree of 38.5%,38.5%,24.2%,and 21.9%,*** produced calcite duringβ-C_(2)S carbonation decreased as the water-to-solid ratio increased,with an increase in content of metastable CaCO_(3)of vaterite and *** thermodynamic stability of CaCO_(3)produced during carbonation was C_(3)A>C_(4)AF>β-C_(2)S>C_(3)*** carbonation degree of Portland cement was predicted based on the results of pure minerals and the composition of cement,and the error of predicted production of CaCO_(3)was only 1.1%,which provides a potential method to predict carbonation properties of systems with a complex mineral composition.

关键词： accelerated carbonation portland cement calcium carbonate water-to-solid ratio

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浅谈法医病理学研究生实践与科研能力并重的培养方法

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教育教学论坛 2024年第6期 34-37页

作者：杨根梦王尚文曾晓锋昆明医科大学法医学院云南昆明650500

法医病理学是法医学的一门主干学科,是一门实践性很强的学科,主要为案件的侦查或审判提供医学证据。法医病理学的发展关乎国计民生和社会稳定。随着国家和社会对高层次专门人才的需求,加强研究生教育、培养高素质的研究生、提升研究生... 详细信息

法医病理学是法医学的一门主干学科,是一门实践性很强的学科,主要为案件的侦查或审判提供医学证据。法医病理学的发展关乎国计民生和社会稳定。随着国家和社会对高层次专门人才的需求,加强研究生教育、培养高素质的研究生、提升研究生科研能力和实践能力是我国法医病理研究生教育亟须解决的重要问题。探索培养法医病理学研究生实践与科研能力并重的方法,旨在为培养具备较强的综合型高素质法医学人才提供新思路与新方法。

关键词：法医学法医病理学研究生培养实践能力科研能力

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高铁发展对民航运输的影响及其应对措施研究

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智能城市应用 2024年第5期7卷 33-35页

作者：王尚民航局运行监控中心北京100010

近年来高铁逐渐成为人们出行的首选,高铁的迅猛发展也对民航运输产生了一定的影响,特别是在短途航线上。基于此,航空公司不得不重新审视自身的运营模式和市场竞争策略,寻求应对之道。本篇文章研究高铁发展对民航运输的影响,并提出相应... 详细信息

近年来高铁逐渐成为人们出行的首选,高铁的迅猛发展也对民航运输产生了一定的影响,特别是在短途航线上。基于此,航空公司不得不重新审视自身的运营模式和市场竞争策略,寻求应对之道。本篇文章研究高铁发展对民航运输的影响,并提出相应的应对措施,以引导航空公司应对新的市场环境,实现与高铁共同发展的目标。

关键词：高铁发展民航运输影响应对措施

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