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Electrical properties of yttrium calcium oxyborate crystal annealed at high temperature and low oxygen partial pressure

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Journal of Materiomics 2019年第3期5卷 363-371页

作者： Shiwei Tian Lili Li Feifei Chen Chao Jiang Fapeng Yu Yanlu Li Xiulan Duan zhengping wang Shujun Zhang Xian Zhao State Key Laboratory of Crystal Materials Advanced Research Center for Optics of Shandong UniversityJinan250100China ISEM Australia Institute of Innovative MaterialsUniversity of WollongongWollongongNSW2500Australia

The yttrium calcium oxyborate crystal(YCa_(4)O(BO_(3))_(3),YCOB)has been actively studied for hightemperature piezoelectric sensing *** this work,the stability of electric properties of YCOB crystal annealed in critical conditions(high-temperatures of 900-1100℃ with a low oxygen partial pressure of 4×10^(-6) atm for 24 h)was investigated and the recovery mechanism for the electrical resisitivity,dielectric permittivity and dielectric loss were studied,taking advantage of the X-ray photoelectron spectra and the first principle *** electrical resistivity of the annealed YCOB crystal was slightly decreased when compared to the pristine counterpart,being(2-5)×10^(7) Ω·cm at 850*** dielectric permittivity and dielectric loss were found to increase after annealing,showing recoverable behaviours after thermal treatment above 650℃ in *** calculated vacancy formation energy indicates that the oxygen vacancy is the dominant defects in *** formation of oxygen vacancy weakens the chemical bonding strength between B(Ca or Y)and O atoms,introduces extra donor levels in the band gap,which excites the electrons to conduction band more easily thus enhances the electrical conductivity and dielectric *** recovered electrical properties are believed to be associated with the reduced vacancy defects at elevated temperatures in air.

关键词： YCOB crystal Recoverable dielectric properties First principle calculations

Exogenous ketogenic supplements can mitigate the susceptibility to Alzheimer’s disease induced by chronic sleep deprivation:emerging role of Sirt1 in ferroptosis

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Food Science and Human Wellness 2024年

作者： Yueqi Yang Xueyan wang Lu Chen Ning Zhang Shilei Ji zhengping wang Jun Han Yuming wang Min Wen Institute of Biopharmaceutical Research， Liaocheng University College of Food Science and Engineering， Ocean University of China Pet Nutrition Rresearch and Development Center， Gambol Pet Group Co.，Ltd.

Emerging evidence supports that sleep disorders are the main risk factor for sporadic Alzheimer’s disease (AD)， and iron dysregulation may be the link between them. Our previous studies have confirmed that ketogenic diet (KD) can prevent chronic sleep deprivation-induced AD. However， it is uncertain whether exogenous ketones supplements (EKS)， as an alternative intervention， have the same effects as KD. Thus， we investigated the prophylactic efficiency of EKS on chronic sleep deprivation-induced AD and reveal the underlying mechanism focus on iron metabolism. We observed that the prophylactic efficacy of EKS against chronic sleep deprivation-induced AD was comparable to that of KD. Meanwhile， our results suggest that both EKS and KD inhibited iron metabolism disorder through regulation of iron metabolism-related proteins. Moreover， we found that both EKS and KD reduced hippocampal mitochondrial dysfunction and iron-mediated lipid peroxides. Furthermore， EX527 (Sirt1 inhibitor)， mostly abrogated these above protections of EKS， suggesting that the prophylactic effect of EKS on AD is partly dependent on Sirt1. Our findings provide novel evidence that EKS can be developed as functional foods to prevent or delay the development of AD， particularly in individuals with sleep disorders.

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Two-dimensional tellurene nanosheets as saturable absorber of passively Q-switched Nd:YAG solid-state laser

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Chinese Optics Letters 2020年第4期18卷 26-31页

作者： Tianhong Tang Fang Zhang Mengxia wang zhengping wang Xinguang Xu State Key Laboratory of Crystal MaterialsShandong University Jinan 250100China Key Laboratory of Functional Crystal Materials and Device(Shandong University) Ministry of EducationJinan 250100China

For the first time,a group-Ⅵsingle element nanomaterial was used as the optical saturable absorber(SA)to generate laser *** two-dimensional(2D)tellurene as a passive Q-switch,1.06μm and 1.3μm pulse laser operations were realized from a diode-pumped Nd:YAG *** shortest pulse widths were 98 ns and 178 ns,and the highest peak powers were 2.68 W and 2.45 W,*** research determines that tellurene is an excellent SA material in the near-infrared region.

关键词： tellurene nanosheets absorber graphene passive Q-switching

Smart Manufacture Process and Structure for Composite Materials

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High Technology Letters 2001年第4期7卷 92-96页

作者：张宝友 Zhang Deqing wang zhengping Huang Longnan Liu Zhiqiang Li Xiaofeng Xia Weiguang Li Chensha Center for Analysis and Measurement Harbin Institute of Technology Department of Material Research Harbin Engineering University Chemistry Engineering Department Harbin Engineering University Material academy Harbin Institute of Technology Harbin Turbine Company LTD HAMON (china) S.A. Beijing Office Research Lab. of Composite Materials Harbin Institute of Technology

It is difficult to ensure the manufacturing process of composites for the reason that there are complicated processes during curing process of composites. The cure cycle has a significant effect on the quality of the finished part. The traditional cure cycle based on empirical approach could not ensure the quality of cured products because of unstabilized performance, high cost of production and low efficiency. As complex intelligent manufacturing systems are developed increasingly in industry, the necessity of more user friendly operation system is becoming progressively importance for their utilization and market value. This paper introduces some of the recent technological advances in the intelligent manufacturing systems that will influence the design and development of relevant industry.

关键词： Smart system Manufacturing Structure Composites

Impact factors of fractal analysis of porous structure

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Science China(Technological Sciences) 2010年第2期53卷 348-351页

作者： TANG HuiPing, ZHU JiLei, XI zhengping, DI XiaoBo, wang JianYong & AO QingBo State Key Laboratory of Porous Metal Materials, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China 1. State Key Laboratory of Porous Metal Materials Northwest Institute for Nonferrous Metal Research Xi’an 710016 China

Characterization of pore structure is one of the key problems for fabrication and application research on porous materials. But, complexity of pore structure makes it difficult to characterize pore structure by Euclidean geometry and traditional experimental methods. Fractal theory has been proved effective to characterize the complex pore structure. The box dimension method based on fractal theory was applied to characterizing the pore structure of fiber porous materials by analyzing the electronic scanning microscope (SEM) images of the porous materials in this paper. The influences of image resolution, threshold value, and image magnification on fractal analysis were investigated. The results indicate that such factors greatly affect fractal analysis process and results. The appropriate magnification threshold and fractal analysis are necessary for fractal analysis.

关键词： porous materials fractal dimension porous structure

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高超声速巡航下动力耦合的配平设计方法

西北工业大学学报 2010年第5期28卷 780-785页

作者：钟范俊王正平西北工业大学航空学院陕西西安710072

吸气式高超声速飞行器的动力因素对总体性能的影响至关重要,为了获得良好的气动、推进及其耦合下的性能,保证巡航飞行特性,必须进行布局、动力的耦合设计。文章提出了一种新的探索高超声速巡航下布局/动力耦合的配平设计方法,这在第1、... 详细信息

吸气式高超声速飞行器的动力因素对总体性能的影响至关重要,为了获得良好的气动、推进及其耦合下的性能,保证巡航飞行特性,必须进行布局、动力的耦合设计。文章提出了一种新的探索高超声速巡航下布局/动力耦合的配平设计方法,这在第1、2节中予以阐明。2.1小节以一种不同于X-43A所采用的方法划分了API和EPI;2.2小节最终选取压强p作为耦合动力参数;2.3小节则讨论了需要实现的耦合设计条件。第3节通过图3至图8呈现了数值模拟的结果和相应分析。3.1小节对一体化的机体/发动机组合进行马赫数Ma=6的三维流场数值模拟,其核心是确定不同迎角下维持推阻平衡所需的压强;p 3.2小节计算了不同p、α组合状态下的气动、推进特性;3.3小节则探讨了动力耦合条件下的力矩配平。最后,第4节给出了文中研究的4个初步结论。

关键词：计算流体力学高超声速巡航吸气式布局/动力耦合推阻平衡力矩配平

法拉第旋光器温度特性对无源解调全光纤电流互感器的影响

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电网技术 2013年第1期37卷 206-210页

作者：王玥坤王政平孙帅哈尔滨工程大学理学院黑龙江省哈尔滨市150001

无源调制式光纤电流互感器在原有的In-line光纤电流互感器结构基础上加入了22.5的法拉第旋光器用以达到将信号检测的工作点移到最敏感的位置且同时提高系统的抗扰度的目的。为促进无源解调型全光纤电流互感器的实用化进程,根据制备法拉... 详细信息

无源调制式光纤电流互感器在原有的In-line光纤电流互感器结构基础上加入了22.5的法拉第旋光器用以达到将信号检测的工作点移到最敏感的位置且同时提高系统的抗扰度的目的。为促进无源解调型全光纤电流互感器的实用化进程,根据制备法拉第旋光器的法拉第晶体温度特性,从理论上分析了法拉第旋光器温度特性对无源解调全光纤电流互感器温度稳定性的影响,并针对不同种温度特性各异的法拉第晶体采用数值计算的方法对法拉第旋光器温度特性对系统输出的温度稳定性的影响进行了评估。

关键词：光纤电流互感器法拉第旋光器无源解调温度特性法拉第效应

Ketogenic diet prevents chronic sleep deprivation induced cognitive deficiency in mice by inhibiting ferroptosis via Sirt1/PGC-1α/Nrf2 signaling pathway

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Ketogenic diet prevents chronic sleep deprivation induced co...

Information on ICHTROI’1994 and IFCSE

中国营养学会第十五届全国营养科学大会

作者： Xueyan wang Aiai Xiao zhengping wang Min Wen Liaocheng University

Sleep deprivation(SD) induces cognitive deficiency is closed with hippocampal neuron loss. Emerging evidence indicated that ferroptosis participates in cognitive impairment in varied neurodegenerative diseases. However, whether ferroptosis participates in SD-induced cognitive impairment remains unclear. Ketogenic diet(KD) is well known for its neuroprotective effect, but little is known about its prophylactic efficacy against SD-induced cognitive deficiency. This study was designed to explore the prophylactic efficacy and mechanism with a focus on ferroptosis of KD on SD-induced cognitive deficiency using a chronic sleep deprivation mice model. Methods In the present work, mice were cotreated with standared diet or KD during 21 days SD expose. The cognitive ability, cerebral oxidative stress, ferroptosis and Sirt1/PGC-1α/Nrf2 pathway were detected. Results There were several major findings:(1) KD could prevent SD-induced cognitive deficeincy in SD-exposed mice;(2) Ferroptosis involves in the SD-induced cognitive deficiency;and(3) KD inhibits ferroptosis via Sirt1-PGC-1α-Nrf2 pathway in the hippocampus of SD-exposed mice. Conclusion The present results firstly indicated that ferroptosis is involved in the SD-induced cognitive deficiency and KD could prevent them through Sirt1/PGC-1α/Nrf2 pathways. Our results suggested that KD may serve as potent dietary prophylaxis for SD-induced cognitive deficiency and providing new sight to understand the neuroprotective mechanism of ketogenic diet.

关键词： ketogenic diet sleep deprivation cognitive deficiency ferroptosis

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Journal of Earth Science 1993年第1期12卷 63-63页

作者： wang zhengping Wuhan 430030 P R China

The 1994 International Conference on High Technology Reform Old Industry(ICHTROI’1994)will take placeon October 15-19 ,1994,in Wuhan,*** will be sponsored by the Wuhan Society of System Engineering(WSSE),Hubei University,University of Hongkong,Wuhan University,Youth Committee of China Association forModern Design Science(CAMDS),George Washington University,University of Stuttgart,University of Antwerp,University of Chiba et al..This great conference gathers together academic exchange,deciding on awards through discussion to thesis,hold-

关键词： Information on ICHTROI and IFCSE