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Atomic scale electronic structure of the ferromagnetic semiconductor Cr2Ge2Te6

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Science Bulletin 2018年第13期63卷 825-830页

作者： Zhenqi Hao Haiwei li Shunhong Zhang xintong li Gaoting lin Xuan Luo Yuping Sun Zheng liu Yayu Wang State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Institute for Advanced Study Tsinghua UniversityBeijing 100084China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China University of Sdence and Technology of China Hefei 230026China e High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China High Magnetic Field Laboratory Chinese Academy of SdencesHefei 230031China Collaborative Innovation Centre of Advanced Microstructures Nanjing UniversityNanjing 210093Chinag Collaborative Innovation Center of Quantum Matter Beijing 100084China

Cr_2Ge_2Te_6is an intrinsic ferromagnetic semiconductor with van der Waals type layered structure,thus represents a promising material for novel electronic and spintronic *** we combine scanning tunneling microscopy and first-principles calculations to investigate the electronic structure of Cr_2Ge_2Te_*** spectroscopy reveals a surprising large energy level shift and change of energy gap size across the ferromagnetic to paramagnetic phase transition,as well as a peculiar double-peak electronic state on the Cr-site *** features can be quantitatively explained by density functional theory calculations,which uncover a close relationship between the electronic structure and magnetic *** findings shed important new lights on the microscopic electronic structure and origin of magnetic order in Cr_2Ge_2Te_6.

关键词： Ferromagnetic semiconductor Electronic structure Scanning tunneling microscopy Density functional theory

Exosomes derived from microglia overexpressing miR-124-3p alleviate neuronal endoplasmic reticulum stress damage after repetitive mild traumatic brain injury

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Neural Regeneration Research 2024年第9期19卷 2010-2018页

作者： Yan Wang Dai li Lan Zhang Zhenyu Yin Zhaoli Han xintong Ge Meimei li Jing Zhao Shishuang Zhang Yan Zuo Xiangyang Xiong Han Gao Qiang liu Fanglian Chen Ping Lei Department of Geriatrics Tianjin Medical University General HospitalTianjinChina Tianjin Geriatrics Institute Tianjin Medical University General HospitalTianjinChina Tianjin Neurological Institute Tianjin Medical University General HospitalTianjinChina

We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain ***,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains *** this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of *** found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum ***,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured ***,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly *** findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum ***,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.

关键词： apoptosis C/EBP homologous protein endoplasmic reticulum stress exosome inositol-requiring enzyme 1α microglia miR-124-3p neuron repetitive mild traumatic brain injury X-box binding protein 1

Study on a Polyamine-Based Anti-Collapse Drilling Fluid System

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Open Journal of Yangtze Oil and Gas 2022年第3期7卷 203-212页

作者： Wenwu Zheng Fu liu Jing Han Binbin He Shunyuan Zhang Qichao Cao Xiong Wang xintong li Sinopec Group North China Petroleum Engineering Co Ltd. Zhengzhou China Overseas Institute of China Petroleum Corporation Engineering Technology Research Institute Beijing China Yangtze University Jingzhou China

In complex strata, oil-based drilling fluid is the preferred drilling fluid system, but its preparation cost is high, and there are hidden safety risks. Therefore, the new progress of high-performance anti-collapse water-based drilling fluid at home and abroad is analyzed. It is difficult to prevent and control the well collapse. Once the well wall instability problem occurs, it will often bring huge economic losses to the enterprises, and the underground safety accidents will occur. In order to ensure the stability of the well wall and improve the downhole safety, the key treatment agent of water-based collapse drilling fluid is selected, the anti-collapse drilling fluid system is formulated, the evaluation method of drilling fluid prevention performance is established, and a set of water-based drilling fluid system suitable for easy to collapse strata in China is selected to ensure the downhole safety. The development trend of high performance anti-collapse water-based drilling fluid is expected to provide a reference for the research of high performance anti-collapse water-based drilling fluid system and key treatment agent.

关键词： Well Wall Stability Anti-Collapse Water-Based Drilling Fluid Evaluation Method High Temperature Resistance Salt Resistance

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Hartree方程的低正则算法

河南师范大学学报（自然科学版） 2022年第4期50卷 60-64页

作者：李雪李新彤天津大学应用数学中心天津300072

构建了一种Fourier积分器来求解非线性Hartree方程,这种指数型积分器是显式的,且可通过快速Fourier变换实现一阶收敛.通过严格的分析,证明对任意的γ>d/2,该格式对于H^(γ+1)空间中的任何初始数据都提供了一阶精度.即,固定时间T,存在常... 详细信息

构建了一种Fourier积分器来求解非线性Hartree方程,这种指数型积分器是显式的,且可通过快速Fourier变换实现一阶收敛.通过严格的分析,证明对任意的γ>d/2,该格式对于H^(γ+1)空间中的任何初始数据都提供了一阶精度.即,固定时间T,存在常数C=C(T,‖u‖_L^(∞)([0,T];H^(γ+1)))>0,使得‖u^(n)-u(t_(n))‖_H^(γ)_((T)^(d))≤Cτ,其中u^(n)为在t_(n)=nτ处的数值解.

关键词： Hartree方程一阶收敛指数型积分器低正则性

Effects of Different Test Conditions on Pollutant Emissions from Methanol-Fueled Vehicles

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Effects of Different Test Conditions on Pollutant Emissions ...

Emission Characteristics of Fine Particles from Different Fuel Injection Mode Vehicles

2023中国汽车工程学会年会暨展览会

作者： li xintong Zheng Jinlong Xie Qiyuan Zhang Ke Chen Zhanwu Lai Shulin China Automotive Technology and Research Center(Guangzhou)Co. Ltd.

Two kinds of emission equipment,FTIR and MEXA,were jointly used to measure unconventional and conventional pollutants of light-duty methanol vehicles,*** the test,several different test methods were operated in order to compare the exhaust emissions of the test ***,the effects of different test conditions,temperatures,and concentrations of methanol gasoline on the exhaust emissions such as ammonia gas（NH）,methanol（CH OH）,acetaldehyde（CH CHO）,carbon monoxide（CO）,and particle number（PN） were *** analyzing the test results,the patterns of emission and fuel consumption of light-duty methanol vehicles were *** study offers a deeper understanding of the patterns by which conventional and unconventional pollutants were discharged from mechanol automobile.

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Emission Characteristics of Fine Particles from Different Fu...

具有输入数据注意力机制的卷积神经网络用于氟化工产品质量预测

2022中国汽车工程学会年会暨展览会

作者： Xie Qiyuan Wang Fengbin li xintong Zhang Ke Zheng Jinlong Lai Shulin Zhang Mingzhi CATARC Automotive Test Center(Guangzhou)Co. Ltd Tianjin University

In this paper,six light-duty gasoline vehicles meeting China Ⅵ emission standard were selected for cold start Worldwide light-duty Test Cycle（WLTC） tests,including two vehicles with Port Fuel Injection（PFI）,two vehicles with Gasoline Direct Injection（GDI） and two vehicles with Mixed Fuel Injection（MFI）.A new condensing particle counter which can measure fine exhaust Solid Particulate Number in the particle size range of 10 nm～2500 nm（SPN10） was used in conjunction with the condensing particle counter which can measure exhaust Solid Particulate Number in the particle size range of 23 nm～2500 nm（SPN23） recommended by the China Ⅵ emission standard to simultaneously measure the Solid Particulate Number（SPN） of the test *** the total amount of particulate matter emissions（#/km） and transient emission（#/cm） of light duty gasoline vehicles were *** results indicate that the amount of particulate matters emitted by gasoline direct injection vehicles is higher than that of mixed fuel injection vehicles,and much higher than that of port fuel injection ***,the number of fine particles emitted by vehicles with particle size above 10 nm using port fuel injection technology is about 1.5 times that of particles emitted by vehicles with particle size above23 *** reason for this phenomenon is that the port fuel injection technology will generate more sulfate,small particles of unburned hydrocarbon and other fine particle *** total amount of particulate matter emitted by sub-vehicles with particle size above 10 nm cannot meet the recommended value of 1×10#/km proposed by the European Commission League for Low Vehicles Emission（CLOVE）.Therefore,it will be a trend for light-duty gasoline vehicles to be equipped with efficient GPF after the next stage of regulation is determined.

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化工进展 2022年第2期41卷 593-600页

作者：李欣铜陈志冰魏志强李苏桐陈旭宋凯天津大学化工学院天津300350 航天长征化学工程股份有限公司北京100176 巨化清安检测科技有限公司浙江衢州324004 巨化股份有限公司浙江衢州324004

在氟化工等复杂的化工过程中,具有不同时间尺度的时变特性同时存在并作用于系统运行。这类复杂的强时变特性严重制约着各种先进控制策略的广泛应用。为了克服关键质量变量测量滞后所带来的不利因素,进一步提高氟化工过程先进控制系统的... 详细信息

在氟化工等复杂的化工过程中,具有不同时间尺度的时变特性同时存在并作用于系统运行。这类复杂的强时变特性严重制约着各种先进控制策略的广泛应用。为了克服关键质量变量测量滞后所带来的不利因素,进一步提高氟化工过程先进控制系统的控制精度,本文提出了一种具有输入数据注意力机制的卷积神经网络(ACNN)并用于产品质量预测。通过引入注意力机制自适应地提取不同时间跨度输入数据的时间特性,来克服常规卷积神经网络因输入数据窗口固定而无法充分利用各类时变尺度特性的弊端,从而更为精准地提取氟化工过程复杂的强时变特性,更加准确地预测产品质量,辅助工业生产。应用氟化工过程真实数据和TE(Tennessee Eastman)模拟数据验证了方法的有效性和泛化性,结果表明对于强时变或同时具有长时间跨度的漂移波动而言,ACNN的质量预测模型具有更高的可靠性。

关键词：注意力机制卷积神经网络氟化工过程质量预测

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技术赋能:美国教育信息化的历史转向及未来发展趋势

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现代教育管理 2022年第6期 120-128页

作者：李欣桐李广徐哲亮东北师范大学教育学部吉林长春130024 长春建筑学院图书馆吉林长春130607

美国教育信息化发展经历了孕育萌芽、崛起成长和全面发展阶段三个重要历史时期,完成了由角色转型到问题解决,再到技术赋能的历史转向。未来,美国教育信息化将由“抽象空洞”的理论走向“具体鲜活”的实践,形成适应时代发展需要的信息技... 详细信息

美国教育信息化发展经历了孕育萌芽、崛起成长和全面发展阶段三个重要历史时期,完成了由角色转型到问题解决,再到技术赋能的历史转向。未来,美国教育信息化将由“抽象空洞”的理论走向“具体鲜活”的实践,形成适应时代发展需要的信息技术能力。借鉴美国经验,我国教育信息化要注重教育信息化政策的连续性、渐进性与全局性布局;注重教育信息化政策的基础性、均衡性、补偿性的基础建设;形成多元主体参与、多部门协同管理、多组织共同治理的管理机制;开展教育信息化的系统性、科学性、个性化的评估体系建设以及ICT能力的评估。

关键词：教育信息化信息技术整合技术赋能信息技术能力美国历史转向

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Machine learning identification of impurities in the STM images

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Chinese Physics B 2020年第11期29卷 81-85页

作者： Ce Wang Haiwei li Zhenqi Hao xintong li Changwei Zou Peng Cai Yayu Wang Yi-Zhuang You Hui Zhai Institute for Advanced Study Tsinghua UniversityBeijing 100084China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of ChinaBeijing 100872China Frontier Science Center for Quantum Information Beijing 100084China Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA

We train a neural network to identify impurities in the experimental images obtained by the scanning tunneling microscope(STM)*** neural network is first trained with a large number of simulated data and then the trained neural network is applied to identify a set of experimental images taken at different *** use the convolutional neural network to extract features from the images and also implement the attention mechanism to capture the correlations between images taken at different *** note that the simulated data can capture the universal Friedel oscillation but cannot properly describe the non-universal physics short-range physics nearby an impurity,as well as noises in the experimental *** we emphasize that the key of this approach is to properly deal with these differences between simulated data and experimental *** we show that even by including uncorrelated white noises in the simulated data,the performance of the neural network on experimental data can be significantly *** prevent the neural network from learning unphysical short-range physics,we also develop another method to evaluate the confidence of the neural network prediction on experimental data and to add this confidence measure into the loss *** show that adding such an extra loss function can also improve the performance on experimental *** research can inspire future similar applications of machine learning on experimental data analysis.

关键词： scanning tunneling microscope neural network attention data regularization