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Chinese Physics Letters 2004年第7期21卷 1405-1408页

作者： YAOGuo-zheng WANGDing-xiong DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074

The correlation of screw-instability in black hole magnetosphere with pairs of high-frequency quasi-periodic oscillations (HFQPOs) is discussed in the coexistence of the Blandford–Znajek (BZ) and magnetic coupling (MC) processes. It turns out that screw-instability can result in HFQPOs. Such an HFQPO can be regarded as the transient process in an equivalent circuit with resistor and inductor in series (R-L circuit), and its period can be estimated by the relaxation time of this process. When the BZ process and the MC process coexist, the screw-instability can occur both in the BZ region and in the MC region, and the pairs of HFQPOs can be generated. Calculations show that such pairs of HFQPOs are likely to show frequencies in a 3:2 ratio. The frequencies of pairs of HFQPOs in our model scale inversely with the mass of central black hole, which is consistent with the observations.

关键词： Magnetic couplings

ARTIFICIAL BOUNDARY METHOD FOR THE THREE-DIMENSIONAL EXTERIOR PROBLEM OF ELASTICITY

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Journal of Computational Mathematics 2005年第6期23卷 603-618页

作者： Hou-de Han Chun-xiong zheng Department of Mathematical Sciences Tsinghua University Beijing 100084 China Department of Mathematics University of Science and Technology of China Hefei 230026 China

The exact boundary condition on a spherical artificial boundary is derived for the three-dimensional exterior problem of linear elasticity in this paper. After this boundary condition is imposed on the artificial boundary, a reduced problem only defined in a bounded domain is obtained. A series of approximate problems with increasing accuracy can be derived if one truncates the series term in the variational formulation, which is equivalent to the reduced problem. An error estimate is presented to show how the error depends on the finite element discretization and the accuracy of the approximate problem. In the end, a numerical example is given to demonstrate the performance of the proposed method.

关键词： artificial boundary method unbounded domains elasticity

Recent Advances in Self-assembled Nano-therapeutics

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Chinese Journal of Polymer Science 2018年第3期36卷 322-346页

作者： Chun-xiong zheng Yu Zhao Yang Liu Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryCollege of Chemistryand State Key Laboratory of Medicinal Chemical BiologyNankai UniversityTianjin 300071China

The applications of nanotechnology in biomedicine have gained considerable attentions in recent years owing to the great enhancement of therapeutic *** of self-assembly into nanotechnology has brought tremendous convenience during the formation of *** on distinctive methods of self-assembly,nano-therapeutics have beer~developed to ar~impressive stage with the ability to perform site-specific delivery with temporal and spatial *** review focuses on the recent advances in the preparing methods for nano-therapeutics,and their applications in the treatments of diseases.

关键词： Self-assembly Nano-therapeutics Hydrophobic effect Electrostatic interaction Supramolecular host-guest interaction

On s-uniform property of compressing sequences derived from primitive sequences modulo odd prime powers

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Science China(Information Sciences) 2017年第5期60卷 84-95页

作者： Yupeng JIANG Qun-xiong zheng Dongdai LIN State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Information Science and Technology Institute

Let Z/（p;） be the integer residue ring modulo pewith p an odd prime and e 2. We consider the suniform property of compressing sequences derived from primitive sequences over Z/（p;）. We give necessary and sufficient conditions for two compressing sequences to be s-uniform with α provided that the compressing map is of the form φ(x;, x;,..., x;) = g(x;) + η(x;, x;,..., x;), where g(x;) is a permutation polynomial over Z/（p） and η is an（e-1）-variable polynomial over Z/（p）.

关键词： compressing map linear recurring sequence primitive sequence permutation polynomial s uniform

lncRNA-BBOX1-2通过调控成纤维细胞生长因子受体1促进胃癌的发生和发展

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安徽医药 2025年第1期29卷 57-62,I0002页

作者：孙颖顾玮王吉郑雄上海交通大学医学院附属瑞金医院卢湾分院消化内科上海200020

目的探讨长链非编码RNA(long non-coding RNA,lncRNA)BBOX1-2通过调控成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)对胃癌的发生发展机制的影响。方法回顾性选取2017年4月至2019年1月于上海交通大学医学院附属... 详细信息

目的探讨长链非编码RNA(long non-coding RNA,lncRNA)BBOX1-2通过调控成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)对胃癌的发生发展机制的影响。方法回顾性选取2017年4月至2019年1月于上海交通大学医学院附属瑞金医院卢湾分院接受胃癌根治术30例病人肿瘤组织及癌旁相应正常组织作为研究对象,采用实时定量PCT(real-time PCR,RT-PCR)检测lncRNA-BBOX1-2和FGFR1表达;si-linc-BBOX1-2转染SGC-7901细胞后,通过蛋白质印迹法/细胞存活率分析(MTT)、细胞迁移和侵袭(Transwell)实验、细胞划痕、平板克隆一系列生物学功能实验,检测肿瘤细胞生物学功能及FGFR1表达的变化。结果胃癌组织中的lncRNA-BBOX1-2(3.68±0.58比1.15±0.11)和FGFR1(4.26±0.71比1.19±0.18)表达显著高于癌旁正常组织(P<0.05);si-linc-BBOX1-2转染SGC-7901细胞后,FGFR1表达下调,细胞活力、迁移、侵袭和生存能力明显下降。结论LincRNA-BBOX1-2可通过调控FGFR1的表达介导胃癌细胞的增殖、凋亡、迁移和侵袭,可能为胃癌的治疗提供了新的靶点和潜在的生物学标志物。

关键词：胃肿瘤长链非编码RNA BBOX1-2 成纤维细胞生长因子受体1 调控增殖凋亡

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Subreflector model depending on elevation for the Tianma 65 m Radio Telescope

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Research in Astronomy and Astrophysics 2016年第8期16卷 9-16页

作者： zheng-xiong Sun Jin-Qing Wang Lan Chen Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Shanghai Institute of Technology Shanghai 201400 China

A subreflector adjustment system for the Tianma 65 m radio telescope, administered by Shanghai Astronomical Observatory, has been installed to compensate for gravitational deformation of the main re- flector and the structure supporting the subreflector. The position and attitude of the subreflector are variable in order to improve the efficiency at different elevations. The subreflector model has the goal of improving the antenna＇s performance. A new fitting formulation which is different from the traditional formulation is proposed to reduce the fitting error in the Y direction. The only difference in the subreflector models of the 65 m radio telescope is the bias of a constant term in the Z direction. We have investigated the effect of movements of the subreflector on the pointing of the antenna. The results of these performance measure- ments made by moving the antenna in elevation show that the subreflector model can effectively improve the efficiency of the 65 m radio telescope at each elevation. An antenna efficiency of about 60% at the Ku band is reached in the whole angular range of elevation.

关键词： telescopes -- methods: observational -- methods: data analysis

Nonlinear simulation of multiple toroidal Alfvén eigenmodes in tokamak plasmas

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Chinese Physics B 2020年第2期29卷 346-355页

作者： Xiao-Long Zhu Feng Wang zheng-xiong Wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams of the Ministry of EducationSchool of PhysicsDalian University of TechnologyDalian 116024China

Nonlinear evolution of multiple toroidal Alfven eigenmodes(TAEs) driven by fast ions is self-consistently investigated by kinetic simulations in toroidal *** clearly identify the effect of nonlinear coupling on the beam ion loss,simulations over single-n modes are also carried out and compared with those over multiple-n modes,and the wave-particle resonance and particle trajectory of lost ions in phase space are analyzed in *** is found that in the multiple-n case,the resonance overlap occurs so that the fast ion loss level is rather higher than the sum loss level that represents the summation of loss over all single-n modes in the single-n ***,increasing fast ion beta β_h can not only significantly increase the loss level in the multiple-n case but also significantly increase the loss level increment between the single-n and multiple-n *** example,the loss level in the multiple-n case for β_h=6.0% can even reach 13% of the beam ions and is 44% higher than the sum loss level calculated from all individual single-n modes in the single-n *** the other hand,when the closely spaced resonance overlap occurs in the multiple-n case,the release of mode energy is increased so that the widely spaced resonances can also take *** addition,phase space characterization is obtained in both single-n and multiple-n cases.

关键词： tokamak toroidal Alfve′n eigenmode wave-particle interaction beam ion loss

Video-based measurement and data analysis of traffic flow on urban expressways

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Acta Mechanica Sinica 2011年第3期27卷 346-353页

作者： Xian-Qing zheng zheng Wu Shi-xiong Xu Ming-Min Guo Zhan-Xi Lin Ying-Ying Zhang Department of Mechanics and Engineering Science Fudan University 200433 Shanghai China

A new video-based measurement is proposed to collect and investigate traffic flow parameters. The output of the measurement is velocity-headway distance data pairs. Because density can be directly acquired by the reciprocal of headway distance, the data pairs have the advantage of better simultaneity than those from common detectors. By now, over 33 000 pairs of data have been collected from two road sections in the cities of Shanghai and zhengzhou. Through analyzing the video files recording traffic movements on urban expressways, the following issues are studied：laws of vehicle velocity changing with headway distance, proportions of di0erent driving behaviors in the traffic system, and characteristics of traffic flow in snowy days. The results show that the real road traffic is very complex, and factors such as location and climate need to be taken into consideration in the formation of traffic flow models.

关键词： Traffic flow mode - Video-based - Vehicle recog- nition. Driving behavior - Snowy day traffic

Intrinsic Decoherence on Two-Qubit Heisenberg XX Chain

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Communications in Theoretical Physics 2007年第5期47卷 811-815页

作者： HE zheng-Hong xiong Zu-Hong HU Dong-Mei School of Physics Southwest University Chongqing 400715 China

Quantum teleportation is investigated by using the entangled states of two-qubit Heisenberg XX chain in an external uniform magnetic field as resources in the model of Milburn＇s intrinsic decoherence. Though intrinsic decoherence on quantum entanglement and quantum teleportation exerts different effects in different initial systems, proper magnetic fields and probabilities of different eigenstates in the initial states can weaken the effects.

关键词： Heisenberg chain fidelity intrinsic decoherence entanglement

Coriolis Force Effect on Suppression of Neo-Classical Tearing Mode Triggered Explosive Burst in Reversed Magnetic Shear Tokamak Plasmas

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Chinese Physics Letters 2021年第4期38卷 75-80页

作者： Tong Liu Lai Wei Feng Wang zheng-xiong Wang Key Laboratory of materials Modification by Beams of the Ministry of Education School of PhysicsDalian University of TechnologyDalian 116024China

We numerically investigate the Coriolis force effect on the suppression of an explosive burst,triggered by the neo-classical tearing mode,in reversed magnetic shear configuration tokamak plasmas,using a reduced magnetohydrodynamic model,including bootstrap *** works have shown that applying differential poloidal rotation,with rotation shear located near the outer rational surface,is an effective way to suppress an explosive *** comparison with cases where there is no Coriolis force,the amplitude of differential poloidal rotation required to effectively suppress the explosive burst is clearly reduced once the effect of Coriolis force is taken into ***,the effective radial region of the rotation shear location is broadened in cases where the Coriolis force effect is *** rotation with shear located between the radial positions of qminand the outer rational surface always serves to effectively suppress explosive bursts,which we anticipate will reduce operational difficulties in controlling explosive bursts,and will consequently prevent plasma disruption in tokamak experiments.

关键词： rotation effect rational