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Poleward-moving recurrent auroral arcs associated with impulse-excited Standing hydromagnetic waves

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Earth and Planetary Physics 2019年第4期3卷 305-313页

作者： HuaYu Zhao Xu-Zhi Zhou Ying Liu Qiu-Gang Zong Robert Rankin YongFu Wang QuanQi Shi Xiao-Chen Shen Jie Ren Han Liu XingRan Chen School of Earth and Space Sciences Peking University Beijing 100871 China Department of Physics University of Alberta Edmonton Alberta T6G2J1 Canada School of Space Science and Physics Shandong University Weihai 264209 China Center for Space Physics Boston University Boston Massachusetts 02215 USA

In Earth's high-latitude ionosphere, the poleward motion of east–west elongated auroral arcs has been attributed to Standing hydromagnetic waves, especially when the auroral arcs appear quasi-periodically with a recurrence time of a few minutes. The validation of this scenario requires spacecraft observations of ultra-low-frequency hydromagnetic waves in the magnetosphere and simultaneous observations of poleward-moving auroral arcs near the spacecraft footprints. Here we present the first observational evidence from the multi-spacecraft THEMIS (Time History of Events and Macroscale Interactions during Substorms) mission and the conjugated all-sky imager to support the scenario that Standing hydromagnetic waves can generate the quasi-periodic appearance of poleward-moving auroral arcs. In this specific event, the observed waves were toroidal branches of the Standing hydromagnetic waves, which were excited by a pulse in the solar wind dynamic pressure. Multi-spacecraft measurements from THEMIS also suggest higher wave frequencies at lower L shells (consistent with the distribution of magnetic field line eigenfrequencies), which indicates that the phase difference across latitudes would increase with time. As time proceeds, the enlarged phase difference corresponds to a lower propagation speed of the auroral arcs, which agrees very well with the ground-based optical data.

关键词： poleward-moving auroral arcs ULF waves Standing hydromagnetic waves field-aligned currents solar wind dynamic pressure pulse

Standing surface acoustic wave-assisted fabrication of patterned microstructures for enhancing cell migration

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Bio-Design and Manufacturing 2020年第2期3卷 87-97页

作者： Yancheng Wang Yue Wang Deqing Mei Zongkai Yu Dai Xue State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of Advanced Manufacturing Technology of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Department of Aerospace and Mechanical Engineering The George Washington UniversityWashingtonDC 20052USA

Microfluidic device with patterned microstructures on the substrate surface was used to regulate cell adhesion,morphology,and functions in tissue engineering.We developed a microfluidic device which employing microscale patterned microstructures to achieve enhanced cell adhesion and migration.Biocompatible hydrogel substrates with micro-wavy and lattice-patterned microstructures were fabricated using Standing surface acoustic waves and ultraviolet solidification.After seeding the L929 mouse fibroblast cells onto the patterned substrate of the microfluidic device,we determined that the viability and proliferation rate of cell migration can be greatly enhanced.Furthermore,L929 cells showed two types of gathering modes after 48 h of culturing.Cell growth was guided by the patterned substrate used in the microfluidic device and showed differences in the location distribution.Therefore,the developed microfluidic device with patterned microstructures can extend the application of in vitro cell culturing for future drug development and disease diagnosis.

关键词： Standing surface acoustic waves(SSAWs) Micropatterned structure Dynamic cell culture Microfluidic device

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激光驻波中运动电子的谐波自发辐射

强激光与粒子束 2010年第12期22卷 3007-3010页

作者：周素云袁孝江西科技师范学院通信与电子学院南昌330013 苏州大学现代光学技术研究所江苏苏州215006

采用单电子模型分析了电子在线极化激光驻波中的动力学及谐波自发辐射谱,数值计算了电子在驻波中的运动情况及辐射谱。结果表明:电子在波节和波腹处入射后,其辐射谱出现不同的特征;电子在波节处垂直磁场入射后,在洛伦兹力作用下快速振... 详细信息

采用单电子模型分析了电子在线极化激光驻波中的动力学及谐波自发辐射谱,数值计算了电子在驻波中的运动情况及辐射谱。结果表明:电子在波节和波腹处入射后,其辐射谱出现不同的特征;电子在波节处垂直磁场入射后,在洛伦兹力作用下快速振动并向前运动,其向后辐射的光谱发生红移,向前辐射的光谱发生蓝移,谱线出现展宽;当激光强度或者电子初始能量增大时,这些效应更加突出,以至于产生更高阶谐波,形成连续谱;而电子在波腹处以平行电场的方向入射后,仅在电场作用下作直线运动,其自发辐射谱线没有发生移动和展宽。

关键词：激光驻波运动电子高阶谐波自发辐射谱 Standing wave 电子初始能量直线运动展宽数值计算谱线平行电场模型分析洛伦兹力激光强度光谱电场作用垂直磁场线极化连续谱动力学

Standing the Test of Time

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Beijing Review 2023年第48期66卷 22-23页

作者： Guo Cunhai the Center for Argentine Studies Institute of Latin American Studies of the Chinese Academy of Social Sciences

Argentina is the farthest country from China in the world,about 20,000 km whether you go west or east.And throughout history,this distance had hindered communication and trade.

关键词： Standing throughout Time

Remarks on Novel Coronavirus Response Delivered at a meeting of the Standing Committee of the Political Bureau of the CPC Central Committee, February 3, 2020

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维普期刊数据库

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Qiu Shi 2020年第3期12卷 2-12页

Not long after the outbreak of the coronavirus disease(COVID-19)in Wuhan,on January 7,I set requirements for disease prevention and control while chairing a meeting of the Standing Committee of the Central Committee Political Bureau.On January 20,I made comments on a report on this work,pointing out that it is imperative to attach great importance to the outbreak,and to do everything in our power to control its spread.

关键词： prevention Central Standing

A Friendly Visit for Exchanging Ideas,UnderStanding People’s Wishes and Connecting People’s Hearts:Sidelights on the Visit of H.E Ji Bingxuan,Deputy Chairman,Standing Committee of National People’s Congress and President of CAFIU to Bangladesh,Singapore and Indonesia

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International UnderStanding 2019年第3期 1-4页

作者： Jin Yan 不详

From 15 to 24 June 2019,at the invitation of National Assembly of Bangladesh,Parliament of Singapore and People’s Consultative Assembly of Indonesia,H.E.JiBingxuan,Deputy Chairman,Standing Committee of National People’s Congress and President,Chinese Association for International UnderStanding(CAFIU)led a CAFIU delegation and made friendly visits to the three countries in a bid to exchange ideas,understand people’s wishes and connect people’s hearts.

关键词： Exchanging Ideas Standing Committee Congress and President

Vice-Chairman of NPC Standing Committee and CAFIU Vice-President Ji Bingxuan Visited Albania,Latvia and Canada

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International UnderStanding 2016年第2期 2-,1页

Legislative Work of the National People's Congress and Its Standing Committee over 40 Years of Reform and Opening Up

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Qiu Shi 2019年第2期11卷 36-47页

作者： Xin Chunying the Standing Committee of the 13th National People's Congress

The legislative achievements of the National People’s Congress (NPC) and its Standing Committee can be enumerated at great length, yet their most substantial part has been to form and continuously improve the socialist legal system with Chinese characteristics, which has provided legal guarantees for reform and opening up, and socialist modernization.

关键词： National People's Congress Standing Committee Reform and Opening Up

First normative reference of Standing long jump indicates gender difference in lower muscular strength of Macedonian school children

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Health 2014年第1期6卷 99-106页

作者： Seryozha Gontarev Vujica Zivkovic Lence A. Velickovska Milan Naumovski Faculty of Physical Culture Ss. Cyril and Methodius University Skopje Macedonia

Background: This is the first study to publish the normative reference values for assessment of the level of muscular strength through the “Standing long jump” test carried out on a large sample of Macedonian school children. The normative values encompass a wide span of years (6 - 18). Methods: The research was realized in a large sample of 12618 school children at the age of 6 to 18 years from Macedonia. The sample was divided in 14 groups, according to chronological age and each age group was divided into two subgroups according to the criteria of gender. For estimation of the morphologic characteristics, the following anthropometric measures have been applied: body height in Standing position (cm), body weight (kg), as well as the body mass index (BMI). Children aged 6 or above were invited to take a Standing long jump test. Results: Boys show statistically better results in all age categories in the Standing long jump test than girls, and these differences become bigger with the increase of age, especially after the 14th year

关键词： Fitness Testing Standing Long Jump Gender Children Adolescents Lower Muscular Strength