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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： s.w.chen w.H.Li C.Xu Q.H.Meng school of Energy science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC shenyang Aircraft Design and Research Institute Shenyang 110035China

sweeping jet actuator(sJA)has been widely applied for activeflow control in *** this paper,the sJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both sJA behaviors and sJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with sJA placed near the separation position,close to the endwall and under *** characteristic frequencies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and sJA jets impact region helped to judge that sJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of sJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control sweeping jet actuator Corner separation Oilflow visualization

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2)thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： s X chen M M chen Y Liu D w Cao G J chen Department of Microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with si-based complementary metal-oxide-semiconductor(CMOs)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)

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汞共振辐射形成臭氧的适宜条件和量子产率

化学学报 1957年第3期 179-187页

作者：陈时伟兰州大学化学系

(1)在一大气压下,汞共振辐射中仅1849.6线能直接形成臭氧,2537.5线则不能。（2）氧中有 O4或（O2）2分子时,对光化作用形成臭氧的效果并无影响。（3）根据本实验结果,可以推知2530线确如 Briner 等所指出,不能发生光化形成臭氧作... 详细信息

(1)在一大气压下,汞共振辐射中仅1849.6线能直接形成臭氧,2537.5线则不能。（2）氧中有 O4或（O2）2分子时,对光化作用形成臭氧的效果并无影响。（3）根据本实验结果,可以推知2530线确如 Briner 等所指出,不能发生光化形成臭氧作用,*** 和 Burton 关于2530线形成臭氧的解释,也跟着失去了事实依据。在 warburg 实验中可能实际起作用的为2138线并非2530线。（4）1849.6线形成臭氧的反应机构可能为:O2（3Σg-）+1849.6→2O（3P）O2（3Σg-）+O（3P）+M→O3+M反应的量子总产率应略小于2,实测值为1.87。（5）在本实验情况下,形成臭氧的量子总产率随氧的流速的减小而有显著的减小,随温度的升高而稍减低,受氮冲淡的影响甚微。

关键词：臭氧量子共振辐射总产率幅射露光光子数

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光敏作用形成臭氧的量子产率和反应机构

化学学报 1957年第3期 188-195页

作者：陈时伟兰州大学化学系

(1)汞共振辐射的2537.5线,能经激发汞原子而发生光敏作用,间接形成臭氧。至于1849.6线,则可同时发生光化和光敏作用产生臭氧。（2）2537.5线汞光敏作用形成臭氧的反应机构可能为:Hg（1s0）+2537.5→Hg（3P10）Hg（3P10）+O2（3Σg... 详细信息

(1)汞共振辐射的2537.5线,能经激发汞原子而发生光敏作用,间接形成臭氧。至于1849.6线,则可同时发生光化和光敏作用产生臭氧。（2）2537.5线汞光敏作用形成臭氧的反应机构可能为:Hg（1s0）+2537.5→Hg（3P10）Hg（3P10）+O2（3Σg-）→HgO2HgO2+O2（3Σg-）→HgO+O3量子总产率应近于1,实测的最大值为0.51。1849.6线汞光敏作用形成臭氧的反应机构可能为:Hg（1s0）+1849.6→Hg（1P10）Hg（1P10）+O2（3Σg-）→Hg（1s0）+2O（3P）O2（3Σg-）+O（3P）+M→O3+M量子总产率应小于2,实测的最大值为1.15。（3）量子总产率随气体流速的增加而增加,每一汞原子所生臭氧的分子数随气体流速的增加而减少。（4）量子总产率和每一汞原子形成臭氧的分子数均随汞的蒸气压的减低而增加。每一汞原子在经过反应管吸收辐射形成臭氧的过程中,能发生极大次数的循环。

关键词：光敏作用量子所生分子数臭氧汞原子反应

TDP-43 is a key molecule accelerating development of Alzheimer’s disease following traumatic brain injury

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Neural Regeneration Research 2024年第5期19卷 955-956页

作者： Chu chen Department of Cellular and Integrative Physiology Long School of MedicineUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA

Currently,more than 55 million people have dementia worldwide and Alzheimer’s disease(AD)is one of the most common causes of dementia in ***,no effective therapies are currently available for the prevention and treatment of *** is largely due to our limited understanding of the mechanisms underlying the neuropathogenesis of *** has widely been recognized that AD is heterogeneous and that multi-factors are contributing to the pathogenesis of *** evidence suggests that traumatic brain injury(TBI)is an important risk factor for the development of AD and dementia later in life(Guo et al.,2000;Johnson et al.,2010).However,the precise mechanism by which TBI contributes to developing AD has yet to be elucidated.

关键词： Alzheimer traumatic

A two-step multi-frequency receiver function inversion method for shallow crustal s-wave velocity structure and its application across the basin-mountain range belts in Northeast China

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science China Earth sciences 2024年第3期67卷 687-703页

作者： Ruihao YANG Xu wANG Ling chen Mingye FENG Qifu chen state Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

A shallow crustal velocity structure(above 10 km depth) is essential for understanding the crustal structures and deformation and assessing the exploration prospect of natural resources, and also provides priori information for imaging deeper crustal and mantle structure. Passive-source seismic methods are cost-effective and advantageous for regional-scale imaging of shallow crustal structures compared to active-source methods. Among these passive methods, techniques utilizing receiver function waveforms and/or body-wave amplitude ratios have recently gained prominence due to their relatively high spatial resolution. However, in basin regions, reverberations caused by near-surface unconsolidated sedimentary layers often introduce strong non-uniqueness and uncertainty, limiting the applicability of such methods. To address these challenges, we propose a two-step inversion method that uses multi-frequency P-RF waveforms and P-RF horizontal-to-vertical amplitude ratios. synthetic tests indicate that our two-step inversion method can mitigate the non-uniqueness of the inversion and enhance the stability of the results. Applying this method to teleseismic data from a linear seismic array across the sedimentary basins in Northeast China, we obtain a high-resolution image of the shallow crustal s-wave velocity structure along the array. Our results reveal significant differences between the basins and mountains. The identification of low-velocity anomalies(s^(-1)) at depths less than 1.0 km beneath the Erlian Basin and less than 2.5 km beneath the songliao Basin suggests the existence of sedimentary layers. Moreover, the high-velocity anomalies(~3.4–3.8 km s^(-1)) occurring at depths greater than 7 km in the songliao Basin may reflect mafic intrusions emplaced during the Early Cretaceous. Velocity anomaly distribution in our imaging result is consistent with the location of the major faults, uplifts, and sedimentary depressions, as well as active-source seismic res

关键词： Receiver function Frequency dependence Two-step inversion shallow crustal velocity structures Unconsolidated sedimentary basins

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： s.Tan Q.wang Y.chen w.B.Yao C.Z.Xiao J.F.Myatt school of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China school of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(sRss)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order sRss and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order sRss propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order sRss,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that sRss and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

The impact of the Rural Minimum Living standard Guarantee(Rural Dibao)Program on child nutrition outcomes

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Journal of Integrative Agriculture 2024年第2期23卷 444-456页

作者： Dian chen Xiangming Fang Yu chen Xiaodong Zheng Zhuo chen Rodney B.w.smith Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China school of Public Health Georgia State UniversityAtlanta 30303USA school of Economics Zhejiang Gongshang UniversityHangzhou 310018China College of Public Health University of GeorgiaAthens 30602USA Department of Applied Economics University of MinnesotaSaint Paul 55108USA

The Rural Minimum Living standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural *** the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition *** China Family Panel studies(CFPs),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous *** exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition *** results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of ***,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage *** analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition *** also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor *** findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality.

关键词： Rural Minimum Living standard Guarantee nutrition height-to-age z-scores stunting rural China

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.w.wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Migration Networks Pattern of China’s Floating Population from the Perspective of Complex Network

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Chinese Geographical science 2024年第2期34卷 327-341页

作者： LIU wangbao chen Ranran College of Geography science South China Normal UniversityGuangzhou 510631China

since China’s reform and opening-up,the growing disparity between urban and rural areas and regions has led to massive *** China’s Rural Revitalization strategy and the industrial transfer from the eastern coastal areas to the inland,the migration direction and pattern of the floating population have undergone certain *** the 2017 China Migrants Dynamic survey(CMDs),excluding Hong Kong,Macao,and Taiwan regions of China,organized by China’s National Health Commission,the relationship matrix of the floating population is constructed according to the inflow place of the interviewees and their outflow place(the location of the registered residence)in the questionnaire *** then apply the complex network model to analyze the migration direction and network pattern of China’s floating population from the city *** migration network shows an obvious hierarchical *** first-,second-,third-and fourth-tier distribution cities are municipalities directly under the central government,provincial capital cities,major cities in the central and western regions and ordinary cities in all provinces,*** migration trend is from the central and western regions to the eastern coastal *** migration network has‘small world’characteristics,forming nine *** shows that most node cities in the same community are closely linked and geographically close,indicating that the migration network of floating population is still affected by geographical *** the urban-rural and regional differences will promote the rational distribution this *** is necessary to strengthen the reform of the registered residence system,so that the floating population can enjoy urban public services comparable to other populations,and allow migrants to live and work in peace.

关键词： complex network floating population migration network spatial pattern community structure