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Science China Chemistry 2005年第Z1期48卷 93-96页

作者： CHANG jianhua zheng Shuzhan jian Yajun bai Yinjuan ZHANG Shiping Department of Chemistry Northwest University Xi'an 710069 China Department of Chemistry Northwest University Xi'an 710069 China Department of Chemistry Northwest University Xi'an 710069 China Department of Chemistry Northwest University Xi'an 710069 China Department of Chemistry Northwest University Xi'an 710069 China

A novel ligand of DTPA-dihydropyridine derivative was synthesized by reaction of DTPA-dianhydride with 4-aniline-1,4-dihydropyridine. Its complexes of gadolinium, manganese and iron were prepared. Their spin-lattice relaxivities (T1) were investigated. The results show that the NMR T1 relaxivitives (R1) for complexes of Fe(Ⅲ), Mn(Ⅱ) are less than that of Gd(Ⅲ) complex,which has a high relaxivity (R1) on the surrounding water protons, indicating that the Gd(Ⅲ) complex possesses the precondition to be contrast agents for magnetic resonance imaging.

关键词： diethylenetriaminepentaacetic acid, dihydropyridine, magnetic resonance imaging contrast agent, relaxivity.

A Coordinate Gradient Descent Method for Nonsmooth Nonseparable Minimization

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Numerical Mathematics(Theory,Methods and Applications) 2009年第4期2卷 377-402页

作者： zheng-jian bai Michael K. Ng Liqun Qi School of Mathematical Sciences Xiamen University Xiamen 361005 China Centre for Mathematical Imaging and Vision and Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong Department of Applied Mathematics The Hong Kong Polytechnic University Hung Horn Hong Kong

This paper presents a coordinate gradient descent approach for minimizing the sum of a smooth function and a nonseparable convex *** find a search direction by solving a subproblem obtained by a second-order approximation of the smooth function and adding a separable convex *** a local Lipschitzian error bound assumption,we show that the algorithm possesses global and local linear convergence *** also give some numerical tests(including image recovery examples) to illustrate the efficiency of the proposed method.

关键词： Coordinate descent global convergence linear convergence rate

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin bai Xiaodong Li Peng Ai Wanrong Guo Tuo zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia zheng Hongming bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke

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Neural Regeneration Research 2025年第7期20卷 2015-2028页

作者： jian Yang jiang Wu Xueshun Xie Pengfei Xia Jinxin Lu Jiale Liu Lei bai Xiang Li zhengquan Yu Haiying Li Department of Neurosurgery&Brain and Nerve Research Laboratory The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Stroke Research Soochow UniversitySuzhouJiangsu ProvinceChina

Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to *** of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve *** is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic ***,there are few studies on oligodendrocyte progenitor cell *** analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral *** analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ***2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet *** further investigation,we established a mouse model of cerebral ischemia/*** found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct *** ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin *** also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor ***2 knockdown rescued demyelination and improved neurological *** findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.

关键词： bioinformatics bulk RNA sequencing ferroptosis ischemic stroke myelin injury oligodendrocyte progenitor cell perilipin-2 single-cell RNA sequencing

Science Letters:Peak-power reduction by the lattice-reduction-aided closest point search for MIMO broadcast channels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1326-1330页

作者： jian-ping zheng Bao-ming bai Xin-mei WANG State Key Laboratory of Integrated Services Networks Xidian University Xi ＇an 710071 China

In this letter, we present a modified vector-perturbation precoding scheme for the multiple-input multiple-output broadcast channel, where a perturbation vector is chosen to take into account both the instantaneous power and the instantaneous peak power of the transmitted signal. This perturbation vector is obtained by using the closest point search, with the aid of the lattice-reduction algorithm. Simulation results show that the proposed scheme yields a tradeoff among power efficiency, peak-to-average power ratio reduction, and complexity.

关键词： Multiple-input multiple-output (MIMO) Broadcast channel (BC) Precoding Peak-to-average power ratio (PAPR) Lattice-reduction (LR)

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI jian ZHOU Gao-Liang YAN zheng-Xin LIU Wei WANG Zhao-Qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

How do high-voltage cathode and PEO electrolyte get along well?EIS analysis mechanism&potentiometric control strategy

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Journal of Energy Chemistry 2024年第9期96卷 424-436页

作者： Xiaodong bai Chaoliang zheng Heng Zhang jian Liu Panpan Wang Baojia Xia jianling Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 201800China

PEO-based all-solid-state electrolytes are extensively utilized and researched owing to their exceptional safety,low-mass-density,and ***,the low oxidation potential of PEO makes the interface problem with the high-voltage cathode extremely *** this work,the impedance of PEO-based all-solid-state batteries with high-voltage cathode(NCM811)was studied at different *** Nyquist plots displayed a gyrate arc at low-frequencies for NCM811/PEO *** on the kinetic modeling,it was deduced that there is a decomposition reaction of PEO-matrix in addition to de-embedded reaction of NCM811,and the PEO intermediate product(dehydra-PEO)adsorbed on the electrode surface leading to low-frequency inductive ***,the distribution of relaxation time shows the dehydra-PEO results in the kinetic tardiness of the charge transfer process in the temporal ***,an artificial interface layer(CEI_(x))was modified on the surface of NCM811 to regulate the potential of cathode/electrolyte interface to prevent the high-voltage deterioration of ***/CEI_(x)/PEO batteries exhibit capacity retentions of 96.0%,84.6%,and 76.8%after undergoing 100 cycles at cut-off voltages of 4.1,4.2,and 4.3 V,***,here the failure mechanism of high-voltage PEO electrolyte is investigated by EIS and a proposed solving strategy is presented.

关键词： PEo-based electrolyte High-voltage cathode Electrochemical impedance spectroscopy Mechanism research Electrochemical characteristic

Digital twin-based sustainable intelligent manufacturing: a review

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Advances in Manufacturing 2021年第1期9卷 1-21页

作者： Bin He Kai-jian bai Shanghai Key Laboratory of Intelligent Manufacturing and Robotics School of Mechatronic Engineering and AutomationShanghai UniversityShanghai 200444People's Republic of China

As the next-generation manufacturing system,intelligent manufacturing enables better quality,higher productivity,lower cost,and increased manufacturing *** concept of sustainability is receiving increasing attention,and sustainable manufacturing is *** digital twin is an emerging technology used in intelligent manufacturing that can grasp the state of intelligent manufacturing systems in real-time and predict system *** intelligent manufacturing based on a digital twin has advantages in practical *** fully understand the intelligent manufacturing that provides the digital twin,this study reviews both technologies and discusses the sustainability of intelligent ***,the relevant content of intelligent manufacturing,including intelligent manufacturing equipment,systems,and services,is *** addition,thesustainability of intelligent manufacturing is ***,a digital twin and its application are introduced along with the development of intelligent manufacturing based on the digital twin ***,combined with the current status,the future development direction of intelligent manufacturing is presented.

关键词： Intelligent manufacturing Digital twin Advanced manufacturing Industry 4.0 Sustainable manufacturing

Effects of HIPing Pressure on Microstructures and Properties of TiAl Alloy

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Journal of Central South University 2000年第3期12卷 140-142页

作者： CHEN jian-xun HUANG bai-yun ZHOU Ke-chao zheng Qing State Key Laboratory for Powder Metallurgy Central South UniversityChangsha 410083China

Blended elemental Ti 34%Al powders (mass fraction), containing 1.5%TiC, were hot isostatic pressed to prepare TiAl alloys. The effects of HIPing pressure on the sintered density, microstructure, constitutions phase were studied in details. The results show that the density of TiAl alloy increases repaidly with the increase of the HIPing pressure. At the same time, with the increase of pressure, the Ti 3Al phase in matrix disappears. TiC reacts with other substance, forming Ti 2AlC phase, which precipitates at grain boundaries. With the increase of hot isostatic pressing(HIPing) pressure, the shrinkage of the alloys increases, the fine spherical Ti 2AlC phase can meet together and forms a needle shape Ti 2AlC, and the amount of needle shaped Ti 2AlC phase increases. The composite material of TiAl containing C can be made easily by HIPing technology.

关键词： TiAl alloy hot isostatic pressing pressure microstructure carbide