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Effects of Electrically Inert Fillers on the Properties of Poly(m-xylene adipamide)/Multiwalled Carbon Nanotube Composites

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Chinese Journal of Polymer Science 2016年第8期34卷 1032-1038页

作者： bo-yuan zhang Qiu-shi Ge 郭朝霞于建 Key Laboratory of Advanced Materials(MOE) Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

The effects of three types of electrically-inert fillers, calcium carbonate （CaCO_3）, talc and glass fiber （GF）, on electrical resistivity, crystallization behavior and dynamic mechanical properties of poly（m-xylene adipamide）（MXD6）/multiwalled carbon nanotube （MWCNT） composites are investigated. The electrical resistivity of MXD6/MWCNT composites is significantly reduced with the addition of inert fillers due to the volume-exclusion effect that leads to increased effective concentration of MWCNTs in MXD6 matrix and also due to improved MWCNT dispersion. The crystallization temperature of MXD6 increases with the addition of MWCNTs, indicating that MWCNTs can act as nucleating agent and induce crystallization of MXD6. The incorporation of inert fillers has no further effect on crystallization behavior of MXD6, but significantly improves the storage modulus of MXD6/MWCNT composite, demonstrating that CaCO_3, talc and GF filled MXD6/MWCNT composites are very promising materials with not only improved electrical property but also excellent mechanical properties.

关键词： Poly(m-xylene diamide) Multiwalled carbon nanotubes Inert fillers Electrical conductivity.

City-Bus-Route Demand-based Efficient Coupling Driving Control for Parallel Plug-in Hybrid Electric Bus

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 168-178页

作者： Qin-Pu Wang Chao Yang Ya-Hui Liu yuan-bo zhang Zhongtong Bus Hold Co. Ltd. State Key Laboratory of Automotive Safety and Energy Tsinghua University

Recently,plug?in hybrid electric bus has been one of the energy?e cient solutions for urban transportation. However,the current vehicle e ciency is far from optimum,because the unpredicted external driving conditions are di cult to be obtained in advance. How to further explore its fuel?saving potential under the complicated city bus driving cycles through an e cient control strategy is still a hot research issue in both academic and engineering area. To realize an e cient coupling driving operation of the hybrid powertrain,a novel coupling driving control strategy for plug?in hybrid electric bus is presented. Combined with the typical feature of a city?bus?route,the fuzzy logic inference is employed to quantify the driving intention,and then to determine the coupling driving mode and the gear?shifting strategy. Considering the response deviation problem in the execution layer,an adaptive robust controller for electric machine is designed to respond to the transient torque demand,and instantaneously compensate the response delay and the engine torque fluctuation. The simulations and hard?in?loop tests with the actual data of two typical driving conditions from the real?world city?bus?route are carried out,and the results demonstrate that the pro?posed method could guarantee the hybrid powertrain to track the actual torque demand with 10.4% fuel economy improvement. The optimal fuel economy can be obtained through the optimal combination of working modes. The fuel economy of plug?in hybrid electric bus can be significantly improved by the proposed control scheme without loss of drivability.

关键词： Hybrid electric vehicle Single?shaft parallel electromechanical powertrain Coupling driving mode Adaptive robust control

Flotation separation of spodumene and albite with activation of calcium ion hydrolysate components

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Rare Metals 2022年第11期41卷 3919-3931页

作者： Xian-Ping Luo Yong-Bing zhang He-Peng Zhou Fan-Xin Xie Zhi-Zhao Yang bo-yuan zhang Cai-Gui Luo Engineering Research Center for High-Efficiency Development and Application Technology of Tungsten Resources(Jiangxi University of Science and Technology) Ministry of EducationGanzhou341000China Jiangxi Province Key Laboratory of Mining and Metallurgy Environmental Pollution Control Jiangxi University of Science and TechnologyGanzhou341000China

It is difficult to separate spodumene and albite by flotation with calcium ion as *** this study,microflotation experiment,solution chemistry calculation,density functional theory(DFT)calculation and X-ray photoelectron spectroscopy(XPS)analysis were conducted to investigate the effect mechanism of c alcium hydrolysate on the flotation separation of spodumene and *** show that the weak interaction intensity of Ca^(2+)with O atoms on the mineral surface makes it difficult to activate minerals *** O atom in the hydroxyl group of Ca(OH)^(+)and Ca(OH)_(2)can be strongly bonded with Al atom on the mineral surface,which greatly improves the adsorption *** the activation of Ca(OH)^(+),the adsorption forms of collectors on the surface of spodumene and albite are quite different,and the adsorption intensity on the surface of spodumene is higher,which is conducive to the flotation separation of spodumene and *** the action of Ca(OH)_(2),the adsorption of the collector on the albite surface is stronger than that of spodumene,which is not conducive to the flotation separation of the two *** adjusting the initial concentration of calcium ions and pulp pH,Ca(OH)^(+)is the main active component,which is the key to improve the separation effect of spodumene and albite.

关键词： Spodumene Albite Calcium ions Hydrolysate components Flotation Separation

Improving properties of fluxed iron ore pellets with high-silica by regulating liquid phase

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Journal of Iron and Steel Research International 2022年第9期29卷 1381-1392页

作者： yuan-bo zhang Xijun Chen Zi-jian Su Shuo Liu Fang Chen Nan-yong Wu Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Yangzhou Pacific Special Materials Co. Ltd.Yangzhou 225211JiangsuChina

With rapid development of the pellet production under the background of green development,high-quality iron concentrates were gradually exhausted;thus,using high-silica iron concentrates was expected to be a promising way to relieve resource pressure for pellet ***,increasing the proportion of high-silica acid pellets into the furnace led to worse blast furnace slag,and the metallurgical properties of high-silica pellets were *** understand the reciprocal effects of basicity(CaO/SiO_(2))and MgO content on the properties of the high-silica pellets,the phase compositions and microstructure were investigated using X-ray diffraction and scanning electron microscope,equipped with energy dispersive X-ray *** results indicated that simply increasing MgO content from O to 2.50 wt.%could decrease the reduction swelling index,but the compressive strength rapidly declined due to the formation of ***,adding CaO to 2.50 wt.%MgO pellets greatly improved the pellet qualities,which could be attributed to a substantial increase in the amount of high-melting-point silicate liquid phase.

关键词： Fluxed pellet High-silica Liquid phase Compressive strength-Reduction swelling

Variational quantum algorithms for scanning the complex spectrum of non-Hermitian systems

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Frontiers of physics 2024年第4期19卷 275-285页

作者： Xu-Dan Xie Zheng-yuan Xue Dan-bo zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong–Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Solving non-Hermitian quantum many-body systems on a quantum computer by minimizing the variational energy is challenging as the energy can be ***,we propose a variational quantum algorithm for solving the non-Hermitian Hamiltonian by minimizing a type of energy variance,where zero variance can naturally determine the eigenvalues and the associated left and right ***,the energy is set as a parameter in the cost function and can be tuned to scan the whole spectrum efficiently by using a two-step optimization *** numerical simulations,we demonstrate the algorithm for preparing the left and right eigenstates,verifying the biorthogonal relations,as well as evaluating the *** also investigate the impact of quantum noise on our algorithm and show that its performance can be largely improved using error mitigation ***,our work suggests an avenue for solving non-Hermitian quantum many-body systems with variational quantum algorithms on near-term noisy quantum computers.

关键词： quantum algorithm non-Hermitian physics quantum manybody systems

On Robust Cross-view Consistency in Self-supervised Monocular Depth Estimation

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Machine Intelligence Research 2024年第3期21卷 495-513页

作者： Haimei Zhao Jing zhang Zhuo Chen bo yuan Dacheng Tao School of Computer Science University of SydneySydney2008Australia Shenzhen International Graduate School Tsinghua UniversityShenzhen518055China School of Information Technology&Electrical Engineering University of QueenslandBrisbane4072Australia

Remarkable progress has been made in self-supervised monocular depth estimation (SS-MDE) by exploring cross-view consistency, e.g., photometric consistency and 3D point cloud consistency. However, they are very vulnerable to illumination variance, occlusions, texture-less regions, as well as moving objects, making them not robust enough to deal with various scenes. To address this challenge, we study two kinds of robust cross-view consistency in this paper. Firstly, the spatial offset field between adjacent frames is obtained by reconstructing the reference frame from its neighbors via deformable alignment, which is used to align the temporal depth features via a depth feature alignment (DFA) loss. Secondly, the 3D point clouds of each reference frame and its nearby frames are calculated and transformed into voxel space, where the point density in each voxel is calculated and aligned via a voxel density alignment (VDA) loss. In this way, we exploit the temporal coherence in both depth feature space and 3D voxel space for SS-MDE, shifting the “point-to-point” alignment paradigm to the “region-to-region” one. Compared with the photometric consistency loss as well as the rigid point cloud alignment loss, the proposed DFA and VDA losses are more robust owing to the strong representation power of deep features as well as the high tolerance of voxel density to the aforementioned challenges. Experimental results on several outdoor benchmarks show that our method outperforms current state-of-the-art techniques. Extensive ablation study and analysis validate the effectiveness of the proposed losses, especially in challenging scenes. The code and models are available at https://***/sunnyHelen/RCVC-depth.

关键词： 3D vision depth estimation cross-view consistency self-supervised learning monocular perception

The raphe nuclei are the early lesion site of gastric α-synuclein propagation to the substantia nigra

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2057-2076页

作者： Chenglu zhang Ruxue bo Tiantian Zhou Naihong Chen Yuhe yuan State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Chinese Academy of Medical Sciences&Peking Union Medical College Institute of Materia MedicaBeijing 100050China

Parkinson's disease(PD)is a neurodegeneration disease withα-synuclein accumulated in the substantia nigra pars compacta(SNpc)and most of the dopaminergic neurons are lost in SNpc while patients are diagnosed with *** the pathology at an early stage contributes to the development of the disease-modifying *** the“gut–brain”hypothesis is proposed to explain the underlying mechanism,where the earlier lesioned site in the brain of gastricα-synuclein and howα-synuclein further spreads are not fully *** we report that caudal raphe nuclei(CRN)are the early lesion site of gastricα-synuclein propagating through the spinal cord,while locus coeruleus(LC)and substantia nigra pars compacta(SNpc)were further affected over a time frame of 7 ***α-synuclein propagation via CRN leads to neuron loss and disordered neuron activity,accompanied by abnormal motor and non-motor *** neuron circuits are observed among CRN,LC,and SNpc,which contribute to the venerability of dopaminergic neurons in *** results show that CRN is the key region for the gastricα-synuclein spread to the *** study provides valuable details for the“gut–brain”hypothesis and proposes a valuable PD model for future research on early PD intervention.

关键词： Raphe nuclei α-Synuclein Gastrointestinal tract Electrophysiology Locus coeruleus Substantia nigra pars compacta Parkinson's disease Spinal cord

Friction as energy dissipation process associated with superlubricity of solids

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Friction 2024年第9期12卷 2083-2088页

作者： bo zhang Saga University Saga-shi 840-8502Japan

The paper shows that work in a quantum system is quantized with energy;the quantum work is equivalent to the highest eigenenergy(the Debye energy)of the system and the superlubricity of solids is derived from the quantum *** prerequisite for the superlubricity is that the lateral force at contact surfaces in sliding is less than the Debye force so that the phonon of the solids is not excited.

关键词： superlubricity phonon friction Plank law Debye frequency

Human umbilical cord mesenchymal stem cells derivedexosomes on VEGF-A in hypoxic-induced mice retinal astrocytes and mice model of retinopathy of prematurity

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1238-1247页

作者： Xiao-Tian zhang bo-Wen Zhao yuan-Long zhang Song Chen Tianjin Eye Hospital Tianjin 300020China Tianjin Key Lab of Ophthalmology and Visual Science Tianjin 300020China

AIM:To observe the effect of human umbilical cord mesenchymal stem cells(hUCMSCs)secretions on the relevant factors in mouse retinal astrocytes,and to investigate the effect of hUCMSCs on the expression of vascular endothelial growth factor-A(VEGF-A)and to observe the therapeutic effect on the mouse model of retinopathy of prematurity(ROP).METHODS:Cultured hUCMSCs and extracted exosomes from them and then retinal astrocytes were divided into control group and hypoxia *** assay,flow cytometry,reverse transcription-polymerase chain reaction(RT-PCR)and Western blot were used to detect related *** mechanisms by which hUCMSCs exosomes affect VEGF-A expression in hypoxia-induced mouse retinal astrocytes were *** last,the efficacy of exosomes of UCMSCs in a mouse ROP model was ***6 was used to comprehensively process data ***:The secretion was successfully extracted from the culture supernatant of hUCMSCs by gradient *** oxygen species(ROS)and hypoxia inducible factor-1α(HIF-1α)of mice retinal astrocytes under different hypoxia time and the expression level of VEGF-A protein and VEGF-A mRNA increased,and the ROP cell model was established after 6h of *** secretions of medium and high concentrations of hUCMSCs can reduce ROS and HIF-1α,the expression levels of VEGF-A protein and VEGF-A mRNA are statistically significant and concentration *** with the ROP cell model group,the expression of phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)/mammalian target of rapamycin(mTOR)signal pathway related factors in the hUCMSCs exocrine group is significantly *** intravitreal injection of the secretions of medium and high concentrations of hUCMSCs can reduce VEGF-A and HIF-1αin ROP model *** staining shows that the number of retinal neovascularization in ROP mice decreases with the increase of the dose of hUCMSCs ***:In a hypoxia induced

关键词： human umbilical cord mesenchymal stem cells retinal astrocytes retinopathy of prematurity vascular endothelial growth factor hypoxia inducible factor