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Some issues on atomic force microscopy based surface characterization

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Optoelectronics Letters 2007年第2期3卷 129-132页

作者： chen yu-hang HUANG Wen-hao Department of Precision Machinery and Instrumentation University of Science and Technology of China Hefei 230026 China

Influences of tip radius and sampling interval on applying atomic force microscopy （AFM） in quantitative surface evaluations are investigated by numerical simulations and experiments. Several evaluation parameters of surfaces ranging from amplitude to functional parameters are studied. Numerical and experimental results are in good agreements. The accuracy of estimating tip radius on random rough surface with Ganssian distribution of heights using a blind reconstruction method is also discussed theoretically. It is found that the accuracy is greatly depending on the ratio of actual tip radius to root-mean-square （rms） radius of curvature. To obtain an accurate estimation of tip radius under Gaussian rough surface, the ratio has to be larger than 3/2.

关键词：原子力显微镜表面特征数值模拟采样间隔

Regional drying and wetting trends over Central Asia based on Koppen climate classification in 1961—2015

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Advances in Climate Change Research 2021年第3期12卷 363-372页

作者： DILINUER Tuoliewubieke YAO Jun-Qiang chen Jing MAO Wei-Yi YANG Lian-Mei YEERNAER Humaerhan chen yu-hang Institute of Desert Meteorology China Meteorological AdministrationUrumqi830002China Center of Central Asia Atmosphere Science Research Urumqi830002China Xinjiang Ecological Environment Monitoring Centre Urumqi830011China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of EducationNanjing University of Information Science&TechnologyNanjing210044China

Central Asia(CA)is one of the most drought-prone regions in the world with complex climate regimes,it is extremely vulnerable to water *** studies on drought in CA,as a whole,have been carried out,whereas there is a lack of studies on the drying and wetting trends of different climatic zones within *** this study,CA was divided into three different climatic zones based on the Koppen climate classification method,precipitation climatology,and aridity *** were the temperate continental(Df),dry arid desert(BW),and Mediterranean continental(Ds)climatic *** regional drying and wetting trends during the years 1961—2015 were investigated using the monthly gridded Standardized Precipitation Evapotranspiration Index(SPEI).The empirical orthogonal function(EOF)was applied to analyze spatial and temporal variation *** mode 1(EOF1)analysis found increasingly wet conditions throughout CA over the duration of the study,and EOF mode 2(EOF2)analysis found a contrast between northern and southern CA:as Df became drier and BW and Ds became *** mode 3(EOF3)analysis found a western and eastern inverse phase *** SPEI displayed a decreasing trend from 1961 to 1974 for CA as a whole,before increasing from 1975 to 2015,with a particularly significant increase over the first seven years of that *** a regional scale,the BW and Ds zones experienced a wetting trend due to increased precipitation during 1961—2015,but the Df zone experienced a drying trend due to reduced evapotranspiration and an increasing temperature,particularly from 1961 to ***,the spatio-temporal patterns in dryness and wetness across CA can be categorized according to climatic regions.

关键词： Drought Breaks for Additive Season and Trend(BFAST) Central Asia SPEI Koppen climate classification

Effects of chitooligosaccharide-zinc on the ovarian function of mice with premature ovarian failure via the SESN2/NRF2 signaling pathway

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Chinese Journal of Natural Medicines 2021年第10期19卷 721-731页

作者： LI Jia chen yu-hang XU Jia-yu LIU Jiang-Ying FU Jia-cheng CAO Xiu-Ping HUANG Jian ZHENG yue-Hui Medical Experimental Teaching Center Nanchang UniversityNanchang 330006China The Second Clinical Medical College Nanchang UniversityNanchang 330006China The First Clinical Medical College Nanchang UniversityNanchang 330006China School of Basic Medicine Nanchang UniversityNanchang 330006China Shenzhen Traditional Chinese Medicine Hospital Shenzhen 518000China Key Laboratory of Reproductive Physiology and Pathology of Jiangxi Province Nanchang UniversityNanchang 330006China

Chitooligosaccharide-zinc(COS·Zn)is a powerful anti-oxidant and anti-aging scavenger,whose anti-oxidative ability immensely exceeds vitamin ***,this study was aimed to investigate the protective effects of COS·Zn against premature ovarian failure(POF)and potential *** KM adult mice were divided into the following groups:a treatment group(150 mg·kg^(−1)·d^(−1) COS·Zn),a treatment group(300 mg·kg^(−1)·d^(−1) COS·Zn),a prevention group,two control groups and two CY/BUS ***·Zn(150,300 mg·kg^(−1)·d^(−1))and COS·Zn(300 mg·kg^(−1)·d^(−1))were therapeutically and preventatively administered to POF mice in the treatment and prevention studies,*** the groups were administered for 21 *** primary and secondary follicles were observed in the COS·Zn-treated groups(including the treatment and prevention groups)than those of the control ***,the ovarian index and the levels of FSH and LH notably increased in the treatment and prevention groups compared with those in the CY/BUS *** levels of MVH,OCT4 and PCNA in the treatment group(300·kg^(−1)·d^(−1) COS·Zn)and MVH in the prevention group remarkably increased compared with those in the CY/BUS ***,the levels of P53 and P16 protein were down-regulated in the treatment and prevention groups compared with those in the CY/BUS ***,the amounts of Sestrin2(SESN2)and SOD2 protein were obviously higher in the treatment group(150 mg·kg^(−1)·d^(−1) COS·Zn)than those in the CY/BUS ***,the amounts of NRF2 and SESN2 protein were up-regulated in the prevention ***,an increased GSH level was observed in the two treatment groups,compared with that in the CY/BUS groups,and the same trend was also present in the prevention *** together,COS·Zn improves the ovarian and follicular development through regulating the SESN2/NRF2 signaling *** results suggest the role of COS·Zn as a novel agent for the treatment and preventi

关键词： Premature ovarian failure Chitooligosaccharide-zinc Sestrin2-nrf2 Ovarian function Aging

用于提高微波无线能量传输系统接收端能量转换效率的肖特基二极管

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物理学报 2020年第10期69卷 235-243页

作者：李妤晨陈航宇宋建军西安科技大学电气与控制工程学院西安710054 西安电子科技大学微电子学院西安710071

转换效率是微波无线能量传输系统的关键参数,为提高该参数指标,本文提出了一种GeOI折叠空间电荷区肖特基二极管,该器件结构可以显著降低肖特基二极管的零偏置电容,利于能量转换效率的提高.通过在ADS仿真软件中使用该器件SPICE模型进行... 详细信息

转换效率是微波无线能量传输系统的关键参数,为提高该参数指标,本文提出了一种GeOI折叠空间电荷区肖特基二极管,该器件结构可以显著降低肖特基二极管的零偏置电容,利于能量转换效率的提高.通过在ADS仿真软件中使用该器件SPICE模型进行整流电路仿真,在输入能量为24.5 dBm时,获得了75.4%的转换效率.

关键词：无线能量传输绝缘层上锗肖特基二极管转化效率

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一种多视角高精度图片的深度估计方法

北京邮电大学学报 2021年第5期44卷 101-106页

作者：李剑陈宇航北京邮电大学人工智能学院北京100876

针对多视图的重建中高精度图片难以有效重建的问题,提出了基于学习的深度估计方法.该方法利用空洞卷积神经网络对图片进行特征提取,利用长短期记忆网络构建并优化三维代价体,并且采取有监督和无监督2种方式进行训练.在2个真实场景中的... 详细信息

针对多视图的重建中高精度图片难以有效重建的问题,提出了基于学习的深度估计方法.该方法利用空洞卷积神经网络对图片进行特征提取,利用长短期记忆网络构建并优化三维代价体,并且采取有监督和无监督2种方式进行训练.在2个真实场景中的多视角图片数据集上的实验结果表明,相比于传统方法和其他基于学习的方法,该网络所需的显存大大减少,因此能用于高精度图片的重建,同时,提高了模型深度预测的准确性和完整性。

关键词：多视图重建循环神经网络高精度图片

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng yu Bai hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao hang Ma Conghui Zhang Yongxin Yang Shuyuan yu Haiye Zhu Yongjiang Sun Hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China yunnan yuntianhua Co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal *** study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer *** other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal *** introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)***,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery

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架空导线径向温差对弧垂计算的影响

华南理工大学学报（自然科学版） 2017年第7期45卷 41-47,54页

作者：刘刚李炀陈垣杨宇航华南理工大学电力学院广东广州510640

建立了钢芯铝绞线径向温度场分布热路模型,利用有限元分析软件对不同载流值下导线截面的温度场进行计算,并分析了径向温差产生的原因,同时设计钢芯层和表层温度分布式实验进行验证.以实验结果为依据,讨论了不同的温差造成的弧垂计算误差... 详细信息

建立了钢芯铝绞线径向温度场分布热路模型,利用有限元分析软件对不同载流值下导线截面的温度场进行计算,并分析了径向温差产生的原因,同时设计钢芯层和表层温度分布式实验进行验证.以实验结果为依据,讨论了不同的温差造成的弧垂计算误差,以及不同档距时的弧垂计算误差.研究结果表明:架空线径向温差随着载流量的提高呈增大趋势,自然对流情况下,表面温度70℃时,钢芯温度达到73.5℃,导致弧垂的计算误差逐渐扩大;在钢芯层和表层温差一定时,档距越大,计算误差越大,而相对误差越小.

关键词：架S导线径向温差有限元分析狐垂

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中美两国贸易争端及其经济效应研究

亚太经济 2018年第6期 48-54,M0005页

作者：夏春莉陈航宇西安理工大学高等技术学院浙江大学经济学院

通过对中美双边关税现状及中美双方关税加征清单研究发现,美国对中国的总体加权关税水平从1. 71%逐步上升至15. 08%,中国对美国的总体加权关税水平从6. 27%逐步上升至16. 91%。运用GTAP模型对中美双方加征关税的经济效应进行模拟发现:... 详细信息

通过对中美双边关税现状及中美双方关税加征清单研究发现,美国对中国的总体加权关税水平从1. 71%逐步上升至15. 08%,中国对美国的总体加权关税水平从6. 27%逐步上升至16. 91%。运用GTAP模型对中美双方加征关税的经济效应进行模拟发现:中国对美国加征关税时,中国的福利水平与不加关税时相差无几,美国的福利水平上升程度有所下降;中美之间的贸易量大幅下降,并且加征关税对中国的总体出口以及美国的总体进口存在显著的贸易转移效应;加征关税使得中国种植业、采矿业、食品加工业、重型制造业、通信运输业的产出有所上升,美国服装纺织业、轻型制造业和其他服务业的产出有所上升。

关键词：中美贸易争端关税壁垒福利水平贸易转移效应 GTAP模型