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Earth and Planetary Physics 2023年第3期7卷 407-413页

作者： Mao Zhang GaoPeng Lu HaiLiang Huang ZhengWei cheng yazhou chen Steven A.Cummer JiaYi Zheng JiuHou Lei School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Atmospheric Optics Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China National Key Laboratory on Electromagnetic Environment Effects Army Engineering UniversityShijiazhuang CampusShijiazhuang 050003China Electrical and Computer Engineering Department Duke UniversityDurhamNC 27708USA

Tweek atmospherics are extremely low frequency and very low frequency pulse signals with frequency dispersion characteristics that originate from lightning discharges and that propagate in the Earth–ionosphere waveguide over long *** this study,we developed an automatic method to recognize tweek atmospherics and diagnose the lower ionosphere based on the machine learning *** differences(automatic−manual)in each ionosphere parameter between the automatic method and the manual method were−0.07±2.73 km,0.03±0.92 cm^(−3),and 91±1,068 km for the ionospheric reflection height(h),equivalent electron densities at reflection heights(Ne),and propagation distance(d),***,the automatic method is capable of recognizing higher harmonic tweek *** evaluation results of the model suggest that the automatic method is a powerful tool for investigating the long-term variations in the lower ionosphere.

关键词： machine learning method tweek atmospherics reflection height D-region ionosphere

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致密油藏大排量注水吞吐技术及参数优化研究

油气藏评价与开发 2024年第5期14卷 727-733页

作者：张益宁崇如陈亚舟姬玉龙赵立阳王爱方黄晶晶于凯怡西安石油大学陕西省油气井及储层渗流与岩石力学重点实验室陕西西安710065 新疆亚新煤层气一五六勘查有限责任公司新疆乌鲁木齐841100 中国石油长庆油田分公司第三采油厂宁夏银川750000 中国石油长庆油田分公司第四采油厂陕西靖边718599

针对致密油藏水平井自然渗吸采收率低和长期衰竭开发后期地层能量如何补充的难题,在储层基本特征、致密油藏注水吞吐采油机理的基础上,提出了大排量水平井注水吞吐。以鄂尔多斯盆地长7段致密油藏为研究对象,选取天然岩心和人造岩心相结... 详细信息

针对致密油藏水平井自然渗吸采收率低和长期衰竭开发后期地层能量如何补充的难题,在储层基本特征、致密油藏注水吞吐采油机理的基础上,提出了大排量水平井注水吞吐。以鄂尔多斯盆地长7段致密油藏为研究对象,选取天然岩心和人造岩心相结合方式,利用核磁共振等方法,通过室内注水吞吐实验研究了自然渗吸和不同注水速度下吞吐动态渗吸的作用范围和微观孔隙动用特征,分析了排量对孔隙动用情况的影响,并开展了焖井时间影响实验,最后利用数值模拟方法对压裂水平井注水吞吐开发的注水量、焖井时间参数进行优化。研究表明:小排量时,注水吞吐主要动用的是大孔隙,中小孔隙动用较低;大排量时,注水吞吐不仅动用了大孔隙,且中小孔隙动用明显提高,使得整体的采收率出现较大增加。随着焖井时间的延长,油水置换作用越充分,使得注水吞吐采出程度越高,但其提高的程度逐渐稳定。对A9井进行数值模拟优化,得到最佳日注水量为900 m^(3),最佳焖井时间为24 d,在矿场试验取得成功,初期日增油2.11 t,有效期365 d,累计增油770 t。

关键词：大排量注水吞吐致密油藏水平井核磁共振数值模拟

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Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the Himalaya-Hengduan mountains,SW China

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Plant Diversity 2024年第2期46卷 247-255页

作者： Xufang chen yazhou Zhang Lishen Qian Renyu Zhou Hang Sun Jianguo chen State Key Laboratory of Plant Diversity and Specialty Crops Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnanChina Yunnan Key Laboratory of Plateau Wetland Conservation Restoration and Ecological ServicesSouthwest Forestry UniversityKunmingYunnanChina

When benefiting other beneficiaries,cushion plants may reciprocally receive feedback *** feedback effects on different sex morphs,however,remains *** this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover *** total beneficiary cover ratio was similar between females and *** produced much less flowers but more fruits than *** results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion *** may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed *** surface areas covered by beneficiaries produced less flowers and fruits than areas without *** addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex ***,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on *** the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion ***,with females possibly suffering greater cost than *** differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics.

关键词： Facilitation intensity Feedback effect Sex-specific facilitation Nurse plant Population dynamics Reproductive function

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超低渗油藏整体宽带压裂技术研究与应用

石化技术 2024年第1期31卷 41-43页

作者：袁亮亮陈亚舟孙大伟张红岗魏波长庆油田第三采油厂宁夏银川750000

针对超低渗油藏储层改造难度大、油井低产低效的问题,近年来在老井初次改造的基础上,开展井组整体重复压裂技术试验,通过“控制缝长、增加带宽”思路对储层进行大规模改造,建立有效驱替,动用侧向剩余油。现场结果表明,实施井组宽带压裂... 详细信息

针对超低渗油藏储层改造难度大、油井低产低效的问题,近年来在老井初次改造的基础上,开展井组整体重复压裂技术试验,通过“控制缝长、增加带宽”思路对储层进行大规模改造,建立有效驱替,动用侧向剩余油。现场结果表明,实施井组宽带压裂显著提高了油井的增油效果,单井日增油较常规压裂增加0.77t,措施有效率达到98%。

关键词：宽带压裂超低渗油藏参数评价评价

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THE ASYMPTOTIC STABILITY OF PHASE SEPARATION STATES FOR COMPRESSIBLE IMMISCIBLE TWO-PHASE FLOW IN 3D

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数学物理学报:B辑英文版 2023年第5期43卷 2133-2158页

作者：陈亚洲 Hakho HONG 施小丁 College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China Address Institute of Mathematics State Academy of SciencesPyongyangD P R Korea

This paper is concerned with a diffuse interface model called Navier-Stokes/CahnHilliard *** model is usually used to describe the motion of immiscible two-phase flows with a diffusion *** the periodic boundary value problem of this system in torus T3,we prove that there exists a global unique strong solution near the phase separation state,which means that no vacuum,shock wave,mass concentration,interface collision or rupture will be developed in finite ***,we establish the large time behavior of the global strong solution of this *** particular,we find that the phase field decays algebraically to the phase separation state.

关键词： Navier-Stokes/Cahn-Hilliard system strong solution existence uniqueness large-time behavior

Printable oil-NiO_(X)hole transport layer enables efficient n-i-p perovskite solar cells with a high thermal stability

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Science China Chemistry 2024年第7期67卷 2335-2340页

作者： yazhou Xu Zhaoyang Chu Hongyu Wang Zhi Xing Baojin Fan Xiaotian Hu Yiwang chen College of Chemistry and Chemical Engineering/Institute of Polymers and Energy Chemistry(IPEC)/Film Energy Chemistry for Jiangxi Provincial Key Laboratory(FEC) Nanchang UniversityNanchang 330031China Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal University Nanchang 330022China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China

Currently,highly efficient n-i-p perovskite solar cells rely on an organic interface layer for high efficiency,especially 2,2',7,7'-tetrakis[N,N-bis(4-methoxyphenyl)ami-no]-9,9′-spirobifluorene(spiro-OMeTAD),but the instability of organic materials in the photothermal field compromises device *** this study,we employ the oleic acid(YS)/oleamine(YA)end-sealing method to achieve uniform dispersion of NiO_(X)nanoparticles,effectively mitigating coagulation resulting from high local concentration and secondary motion ***,the conductivity of the hole transport layer and its energy level alignment with perovskite is enhanced by the additional 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone(F4TCNQ),leading to a remarkable improvement of open-circuit voltage and fill factor,thus the high efficiency of 25.17%and 24.36%on 0.1 and 1.01cm2,***,by realizing an all-inorganic interface layer,an initial efficiency exceeding 90%is maintained even after 2,800 h of heating at 85℃.

关键词： oil-NiO_(X) perovskite solar cells printing technology high efficiency thermal stability

Degeneration of foundation cushion species induced by ecological constraints can cause massive changes in alpine plant communities

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Science China(Life Sciences) 2024年第4期67卷 789-802页

作者： Jianguo chen Xufang chen Lishen Qian yazhou Zhang Bo Li Honghua Shi Lu Sun Christian Schöb Hang Sun Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environment Yunnan Agricultural UniversityKunming 650500China Área de Biodiversidad y Conservación Universidad Rey Juan CarlosMóstoles 28933Spain

Foundational cushion plants can re-organize community structures and sustain a prominent proportion of alpine biodiversity,but they are sensitive to climate *** loss of cushion species can have broad consequences for associated *** potential plant community changes with the population dynamics of cushion plants remain,however,*** eight plant communities along a climatic and community successional gradient,we assessed cushion population dynamics,the underlying ecological constraints and hence associated plant community changes in alpine communities dominated by the foundational cushion plant Arenaria *** population dynamics of Arenaria are attributed to ecological constraints at a series of life history *** functions are constrained by increasing associated beneficiary plants;subsequent seedling establishment is constrained by temperature,water and light availability,extreme climate events,and interspecific competition;strong competitive exclusion may accelerate mortality and degeneration of cushion *** with cushion dynamics,species composition,abundance and community structure gradually *** cushion plants completely degenerate,previously cushion-dominated communities shift to relatively stable communities that are overwhelmingly dominated by *** warming may accelerate the degeneration process of *** of this foundational cushion plant will possibly induce massive changes in alpine plant communities and hence ecosystem functions in alpine *** assessment of the population dynamics of foundation species is critical for an effective conservation of alpine biodiversity.

关键词： alpine ecosystem biodiversity change climate change plant community dynamics foundation species global warming population dynamics

980 nm Near-Infrared Light-Emitting Diode Using All-Inorganic Perovskite Nanocrystals Doped with Ytterbium Ions

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Tsinghua Science and Technology 2024年第1期29卷 207-215页

作者： Zhenglan Ye Taoran Liu Dan chen yazhou Yang Jiayi Li Yaqing Pang Xiangquan Liu Yuhua Zuo Jun Zheng Zhi Liu Buwen cheng State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Intelligent Network Research Institute Zhejiang LabHangzhou 311100China

All-inorganic perovskite(CsPbX3)nanocrystals(NCs)have recently been widely investigated as versatile solution-processable light-emitting *** to its wide-bandgap nature,the all-inorganic perovskite NC Light-Emitting Diode(LED)is limited to the visible region(400-700 nm).A particularly difficult challenge lies in the practical application of perovskite NCs in the infrared-spectrum *** this work,a 980 nm NIR all-inorganic perovskite NC LED is demonstrated,which is based on an efficient energy transfer from wide-bandgap materials(CsPbCl3 NCs)to ytterbium ions(Yb3+)as an NIR emitter doped in perovskite *** optimized CsPbCl3 NC with 15 mol%Yb3+doping concentration has the strongest 980 nm photoluminescence(PL)peak,with a PL quantum yield of 63%.An inverted perovskite NC LED is fabricated with the structure of ITO/PEDOT:PSS/poly-TPD/CsPbCl3:15 mol%Yb3+NCs/TPBi/LiF/*** LED has an External Quantum Efficiency(EQE)of 0.2%,a Full Width at Half Maximum(FWHM)of 47 nm,and a maximum luminescence of 182 cd/m?.The introduction of Yb3+doping in perovskite NCs makes it possible to expand its working wavelength to near-infrared band for next-generation light sources and shows potential applications for optoelectronic integration.

关键词： perovskite nanocrystals rare-earth doping Light-Emitting Diode(LED) near-infrared optical interconnection

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微波脉冲对导航接收机跟踪环路载噪比的影响

国防科技大学学报 2023年第4期45卷 196-204页

作者：赵敏周星陈亚洲陆军工程大学石家庄校区河北石家庄050003

为了明确微波脉冲对导航接收机的最佳干扰参数,通过对微波脉冲干扰下导航接收机跟踪环路相关处理的理论分析,根据微波脉冲谱线、扩频码谱线以及相干积分时间三者之间的关系,提出一种微波脉冲干扰分类方法,推导了不同参数微波脉冲干扰下... 详细信息

为了明确微波脉冲对导航接收机的最佳干扰参数,通过对微波脉冲干扰下导航接收机跟踪环路相关处理的理论分析,根据微波脉冲谱线、扩频码谱线以及相干积分时间三者之间的关系,提出一种微波脉冲干扰分类方法,推导了不同参数微波脉冲干扰下相关输出功率和载噪比,并进行了试验验证。理论分析与试验结果表明,当微波脉冲宽度大于等于扩频码周期且小于相干积分时间时,进入相干积分器带宽内的多条微波脉冲谱线干扰某一条扩频码谱线,该微波脉冲参数对导航接收机的干扰效果最佳,且优于连续波干扰;随着干扰谱线数量增多,跟踪环路相关输出功率值增加,载噪比减小,干扰效果增强。

关键词：导航接收机微波脉冲跟踪环路相关输出功率载噪比