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Magnetoelastic Instability in Ring-Shaped Molecule Magnets with Next-Nearest Neighbor Coupling

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Communications in Theoretical Physics 2009年第12期52卷 1125-1128页

作者： LI Peng-Fei chen yu-guang Department of Mathematics and Physics Shanghai University of Electric Power Shanghai 200090 China pohl Institute of Solid State Physics Tongji University Shanghai 200092 China

In considering next-nearest neighbor （NNN） coupling, we numerically investigate the magnetoelastic instability in ring-shaped mesoscopic antiferromagnetic Heisenberg spin 1/2 systems with spin-phonon interaction. The results indicate that, for antiferromagnetic NNN coupling J2, there may be a critical value J2^c, at which the ground state is dimerized for arbitrary lattice spring constant and beyond and below which the magnetoelastic instability behavior is different from each other. The values of J2^c are irrelevant to the system size. For ferromagnetic NNN coupling, only continuous transition is present from dimerized phase to uniform phase as lattice spring constant is increased.

关键词： single molecule magnets magnetoelastic instability spin-phonon interaction

A Spin-Polarized Current Direction Controller Based on a Nonuniform Rashba Quantum Wire

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Chinese Physics Letters 2013年第5期30卷 127-130页

作者： XU Zhong-Hui XIAO Wen chen yu-guang Department of Physics Tongji UniversityShanghai 200092 Faculty of Information Engineering Jiangxi University of Science and TechnologyGanzhou 341000

A spin-polarized current direction controller scheme is proposed based on a nonuniform Rashba quantum wire. It is shown that |P_(z)^(LR)|=|P_(z)^(RL)|, whereas their signs are opposite, and the effect of this phenomenon is due to the two broken symmetries and the unbroken C_(2)-rotation symmetry of the investigated system. In addition, the spin-polarized current is nonzero even with a strong disorder strength, which demonstrates that this structure may be utilized for potential applications.

关键词： polarized symmetry rotation

Dynamical Process of Dissociation of Excitons in Polymer Chains with Impurities

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Chinese Physics Letters 2011年第9期28卷 221-224页

作者： ZHAO Hong-Xia ZHAO Hui chen yu-guang Department of Physics Tongji UniversityShanghai 200092

Within an extended Su–Schrieffer–Heeger model including impurity interactions,the dynamical process of exciton dissociation in the presence of an external electric field is investigated by using a non-adiabatic evolution *** the action of impurities,the stability as well as the effective mass of the exciton is *** results show that the field required to dissociate the excitons depends sensitively on the strength of the impurity *** the impurity potential strength increases,the dissociation field decreases *** theoretical results are expected to provide useful predictions concerning which polymers with properly impurity-assisted interactions are likely to be more suitable for use in organic solar cells.

关键词： potential method dissociation

Spin-Peierls Instability in the Ferromagnetic Heisenberg Ladder

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Chinese Physics Letters 2013年第3期30卷 158-162页

作者： XU Yin-Jie ZHAO Hui chen yu-guang YAN Yong-Hong Key Laboratory for Advanced Microstructure Materials of the Ministry of Education and Department of Physics Tongji UniversityShanghai 200092 Department of Physics Shaoxing UniversityShaoxing 312000

A two-leg S=1/2 spin ladder with ferromagnetic rung coupling is investigated to reveal the phase transition between the Haldane and columnar dimer *** elastic lattice with the elastic force K is introduced into the system,which induces unstable spin chains towards the spontaneous *** the rung coupling is strong enough,the dimerization along the legs is suppressed and the spin ladder undergoes a phase *** dimerization amplitude is calculated self-consistently by the density-matrix renormalization group *** determine the phase transition boundary,the spin gap,the columnar dimer order parameter and the block-block entanglement entropy are *** results show that the phase boundary between the columnar dimer phase and Haldane phase follows the power law J_(t)-K^(-α).

关键词： transition. method. dimer

Targeting ERK1/2-calpain 1-NF-κB signal transduction in secondary tissue damage and astrogliosis after spinal cord injury

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Frontiers in Biology 2015年第5期10卷 427-438页

作者： Xin Xin yu Vimala Bondada Colin Rogers Carolyn A. Meyer chen guang yu Spinal Cord and Brain Injury Research Center Department of Anatomy and Neurobiology University of Kentucky College of MedicineLexington KY 40536-0509 USA

Neuronal damage, glial inflammation, and astrogliosis/astroglial scar formation are major secondary injury mechanisms that are significant contributors to functional deficits after spinal cord injury （SCI）. The objectives of the study were to evaluate the distinct roles of ERK2 vs. ERK1/2 and ERK1/2-calpain 1 -NF-r,B signal transduction in the tissue damage and astrogliosis/astroglial scar formation following SCI in rats. RNAi approaches, pharmacological intervention （U0126）, Western blot analysis, immunofluorescence analysis, and histological assessment were used to target ERK1/2-calpain 1-NF-KB signal transduction pathway for neuroprotection. Histological staining analysis demonstrated that selectively reducing pERK2 using ERK2 siRNA, but not inhibition of pERK1/2 with U0126, significantly reduced lesion volume and improved total tissue sparing, white matter sparing, and gray matter sparing in spinal cord two weeks after contusive SCI. An ERK1/2-calpain 1-NF-KB signal transduction pathway was involved in the astroglial scar formation after SCI. Blockade of ERK1/2 by U0126 decreased calpain 1 expression 4 h following SCI. Selective calpain 1 reduction by lentiviral shRNA attenuated astroglial NF-κB activity and astroglial scar formation after SCI in rats. Taken together, these results demonstrate the involvement of individual ERK2 and caipain 1 signaling pathways in tissue damage and astrogliosis/astroglial scar formation in animal models of SCI. Therefore, targeting individual ERK and its downstream signal transduction of calpain 1-NF-κB may provide greater potential as novel therapeutics for minimizing tissue damage and astroglial scar formation following SCI.

关键词： calpain 1 ERK1/2 RNAi neurodegeneration astrogliosis spinal cord injury

The conductance and polarization in quantum wires with Rashba and Dresselhaus spin-orbit interactions

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商丘师范学院学报 2008年第12期24卷 53-56页

作者： WANG Da-zhi chen yu-guang- Pohl Institute for Solid State Physics Tongji UniversityShanghai 200092 China

The conductance and polarization are studied in one-dimensional ballistic quantum wire with both Rashba and Dresselhaus spin-orbit *** kinds of structures are considered in the present work,one with mixture of two interactions and the other with sequence structure of *** find that the conductance and polarization are strongly affected by these two *** both interactions we obtain a multi-peak contour of spin polarization and a dramatic oscillation pattern of spin conductance,which are due to the different combination of the two spin-orbit interactions.

关键词：电导技术极化量子线自旋轨道相互作用

Assessment of subtalar joint neutral position： a cadaveric study

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Chinese Medical Journal 2008年第8期121卷 735-739页

作者： chen Yan-xi yu guang-rong MEI Jiong ZHOU Jia-qian WANG Wen Department of Orthopaedics Tongji Hospital of Tongji University Shanghai 200065 China

Background Subtalar joint （STJ） neutral position is the position typically used by clinicians to obtain a cast representation of a patient＇s foot before fabrication of biomechanical functional orthosis. But no method for measuring STJ neutral position has been proven accurate and reproducible by different testers. This study was conducted to investigate the STJ neutral position in normal feet in cadavers. Methods Twelve fresh-frozen specimens of amputated lower legs were used. Pressure-sensitive films were inserted into the anterior and posterior articulation of STJ. The contact areas for various foot positions and under axial loads of 600 N were determined based on the gray level of the digitized film. The STJ neutral positions were determined as the ankle-foot position where the maximum contact area was achieved, because the neutral position of a joint was defined as the position where the concave and convex surfaces were completely congruous. Results In ankle-foot neutral position, the contact area of STJ was （2.79±0.24） cm^2. In the range of motion of adduction-abduction （ADD-ABD）, the maximum contact area was （3.00±0.26） cm^2 when the foot was positioned 10° of ABD （F=-221.361, P 〈0.05）. In the range of motion of dorsiflexion-plantarflexion （DF-PF）, the maximum contact area was （3.61±0.25） cm^2 when the foot was positioned 20° of DF （F=-121.067, P 〈0.05）. In the range of motion of inversion-eversion （INV-EV）, the maximum contact area was （3.14±0.26） cm^2 when the foot was positioned 10° of EV （F=-256.252, P〈0.05）. Conclusions Joints, such as STJ, therefore, are not necessarily in neutral position when the ankle-foot is placed in the traditional concept of neutral position. The results demonstrate that the most approximate STJ neutral position was in the foot Dosition of 10° of abduction, 20° of dorsiflexion and 10° of eversion.

关键词： subtalar joint biomechanics kinematics

一种面向大规模定制的产品平台扩展决策方法研究

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计算机集成制造系统 2006年第11期12卷 1747-1754页

作者：但斌林森陈光毓重庆大学经济与工商管理学院重庆400044 中国嘉陵工业股份有限公司(集团) 重庆400032

为解决产品平台多种扩展方案的优化问题,提出了一种面向大规模定制的产品平台扩展决策方法,建立了基于结合分析和ELECTRE方法的面向大规模定制的产品平台扩展决策模型。建模分为两个步骤,第一步是结合分析模型,通过对目标市场中消费者... 详细信息

为解决产品平台多种扩展方案的优化问题,提出了一种面向大规模定制的产品平台扩展决策方法,建立了基于结合分析和ELECTRE方法的面向大规模定制的产品平台扩展决策模型。建模分为两个步骤,第一步是结合分析模型,通过对目标市场中消费者需求数据的分析,对扩展后产品平台市场绩效进行量化;第二步是构建多目标决策模型,并应用结合分析模型的结果,综合考虑产品平台的市场绩效、扩展成本和扩展周期3个影响因素,对产品平台的扩展方案进行排序,进而做出决策。最后,以摩托车产品平台扩展决策案例说明了该决策方法的可行性。

关键词：大规模定制产品平台决策模型

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu Jing Wu guang Yin Fan‑Zhen Jiao Zhong‑Zhen yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods