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Journal of Systems Engineering and Electronics 2019年第5期30卷 1025-1034页

作者： HUANG Tingting PENG Bo ZHAO yuepu yu zixuan School of Reliability and Systems Engineering Beihang University

Products are often subject to dynamic environmental conditions in field *** stress transition occurs,products may be exposed to instantaneous shocks that result in shock damages to the products,causing a permanent change of the degradation ***,under some conditions,instantaneous shocks also lead to stress drift,causing a temporary change of the degradation *** this paper,a degradation model is proposed to assess the reliability and predict the residual lifetime of products operating in a dynamic environment considering shock damage and stress *** model is established based on a Wiener process which combines a stress-dependent degradation rate function,a shock damage function and a stress drift function in response to the dynamic *** shock damage function is established as a linear function of the stress transition start level and the stress level *** stress drift function is established as the difference value of a specified function at the stress transition start and end levels.A simulation study is presented to demonstrate the application of the model,and a case study for miniature light bulbs is used to validate the effectiveness of the proposed model.

关键词： degradation modeling dynamic environment stress drift shock damage Wiener process

Axial compressive behavior of Moso Bamboo and its components with respect to fiber-reinforced composite structure

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Journal of Forestry Research 2019年第6期30卷 2371-2377页

作者： Xuexia Zhang zixuan yu Yan yu Hankun Wang Jinghao Li Department of Biomaterials International Center for Bamboo and RattanBeijing 100102People’s Republic of China SFA and Beijing Co-built Key Laboratory of Bamboo and Rattan Science and Technology State Forestry AdministrationBeijing 100102People’s Republic of China Forest Products Laboratory U.S.Forest ServiceWisconsinWI 53726USA

Bamboo is a unique fiber-reinforced bio-composite with fibers embedded into a parenchyma cell *** conducted axial compression tests on bamboo blocks prepared from bottom to top,and from inner to outer portions of the *** apparent Young’s modulus and compressive strength of whole thickness bamboo blocks exhibited slight increases with increasing height along the culm,due to slight increases of fiber volume fraction(Vf)from 28.4 to 30.4%.Other blocks showed a significant increase in apparent Young’s modulus and strength from the inner to outer part of the culm wall,mainly owing to a sharp increase of Vf from 17.1 to 59.8%.With a decrease of fiber fraction volume there was a transition from relatively brittle behavior to very ductile behavior in bamboo *** indicated that stiffness and strength of bamboo was primarily due to fiber in compression,and ductility of bamboo was provided by the parenchyma cell matrix acting as a natural fiber-reinforced composite.

关键词： Bamboo Axial compressive behavior Functionally grade structure

Over 12%efficient kesterite solar cell via back interface engineering

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Journal of Energy Chemistry 2022年第12期75卷 321-329,I0008页

作者： yunhai Zhao zixuan yu Juguang Hu Zhuanghao Zheng Hongli Ma Kaiwen Sun Xiaojing Hao Guangxing Liang Ping Fan Xianghua Zhang Zhenghua Su Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and SystemsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060GuangdongChina CNRS ISCR(Institut des Sciences Chimiques de Rennes)UMR 6226Univ RennesRennes F-35000France School of Photovoltaic and Renewable Energy Engineering UNSW SydneySydney NSW 2052Australia Shenzhen University Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060GuangdongChina

Kesterite Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)has attracted considerable attention as a non-toxic and earthabundant solar cell *** selenization of CZTSSe film at high temperature,the reaction between CZTSSe and Mo is one of the main reasons that result in unfavorable absorber and interface quality,which leads to large open circuit voltage deficit(VOC-def)and low fill factor(FF).Herein,a WO_(3)intermediate layer introduced at the back interface can effectually inhibit the unfavorable interface reaction between absorber and back electrode in the preliminary selenization progress;thus high-quality crystals are *** this back interface engineering,the traditional problems of phase segregation,voids in the absorber and over thick Mo(S,Se)_(2)at the back interface can be well solved,which greatly lessens the recombination in the bulk and at the *** increased minority carrier diffusion length,decreased barrier height at back interface contact and reduced deep acceptor defects give rise to systematic improvement in VOCand FF,finally a 12.66%conversion efficiency for CZTSSe solar cell has been *** work provides a simple way to fabricate highly efficient solar cells and promotes a deeper understanding of the function of intermediate layer at back interface in kesterite-based solar cells.

关键词： Cu_(2)ZnSn(S Se)_(4) WO_(3)intermediate layer Crystal growth Minority carrier diffusion length Interface contact quality

Selenization Reaction Mechanisms in Ambient Air-Processed Highly Efficient Kesterite Solar Cells

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Selenization Reaction Mechanisms in Ambient Air-Processed Hi...

Dip2a regulates stress susceptibility in the basolateral amygdala

第十届新型太阳能材料科学与技术学术研讨会

作者： zixuan yu Zhenghua Su Guangxing Liang Shenzhen University

Kesterite semiconductor CuZnSn(SSe)(CZTSSe) is a promising thin-film photovoltaic material due to cheap and nontoxic constituents,and high theoretical *** selenization annealing process is vital for highly efficient kesterite solar *** SnS during annealing is ***,massive S is also introduced,which inevitably leads to plenty of ***,the path of supplementing Sn has never been ***,to play the role of SnS and avoid introducing excess S,the combination strategies of SnS and Sn or SnSe or SnSe are first put *** the composition of the vapor inhibiting Sn loss(gaseous SnSe) and the pathway through which SnSe facilitates the formation of CZTSSe are first *** SnSe is added to SnS in the selenization process,grain fusion is effectively *** high crystalline quality kesterite absorber makes the band bending at the GBs optimal and the interface recombination be effectively ***,the energy level and concentration of Cu and [2Cu+Sn] defects and the energy level of Cu defects are greatly reduced,which indicates a significant reduction in the cation ***,the open-circuit voltage(V) is significantly elevated from 508 mV to 546 mV with increased fill factor(FF) and short-circuit current density(J).Eventually,a state-of-the-art ambient air-processed kesterite device with 12.89% efficiency is achieved.

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Neural Regeneration Research 2025年第6期20卷 1735-1748页

作者： Jing Li zixuan He Weitai Chai Meng Tian Huali yu Xiaoxiao He Xiaojuan Zhu Key Laboratory of Molecular Epigenetics Ministry of Education Institute of Genetics and CytologyNortheast Normal UniversityChangchunJilin ProvinceChina

Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

关键词： 5-hydroxytryptamine acute restraint stress basolateral amygdala CaMKII neurons DIP2A metabolomics neurotransmitters principal component analysis stress susceptibility tryptophan

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柔然文小考

中华文史论丛 2021年第2期 95-121,398页

作者：于子軒北京大學歷史學系

兩種突厥第一汗國時代新釋碑銘即布古特碑婆羅米字母部分和回斯·陶勒蓋Ⅰ碑的語言屬於鮮卑—蒙古語系,只能是柔然語。柔然文是柔然汗國内部的雙語羣體在5世紀六七十年代柔然汗國控制焉耆、龜兹等南疆北部緑洲之際,以這些緑洲中流行的... 详细信息

兩種突厥第一汗國時代新釋碑銘即布古特碑婆羅米字母部分和回斯·陶勒蓋Ⅰ碑的語言屬於鮮卑—蒙古語系,只能是柔然語。柔然文是柔然汗國内部的雙語羣體在5世紀六七十年代柔然汗國控制焉耆、龜兹等南疆北部緑洲之際,以這些緑洲中流行的梵文和吐火羅文B所使用的婆羅米字母爲基礎創製的。柔然汗國選擇婆羅米字母而非粟特字母或漢字拼寫柔然語,有其深刻的歷史原因。柔然汗國開啓了内亞歷史的一個新階段,柔然文的發現有望成爲早期内亞史研究的新起點。

关键词：柔然鮮卑—蒙古語系婆羅米字母布古特碑回斯·陶勒蓋碑

高效液相色谱-串联质谱法测定稻谷和糙米中的溴硝醇

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分析试验室 2024年第3期43卷 415-419页

作者：王飞俞子萱张静天津海关动植物与食品检测中心天津300457

建立了稻谷和糙米中溴硝醇的高效液相色谱-串联质谱检测方法。样品采用酸性乙腈提取,经HLB固相萃取柱净化,以Hypersil GOLD-C_(18)柱分离,在负离子模式下采集数据,基质外标法定量。溴硝醇在电喷雾负离子模式下的母离子m/z 167.8,实际为... 详细信息

建立了稻谷和糙米中溴硝醇的高效液相色谱-串联质谱检测方法。样品采用酸性乙腈提取,经HLB固相萃取柱净化,以Hypersil GOLD-C_(18)柱分离,在负离子模式下采集数据,基质外标法定量。溴硝醇在电喷雾负离子模式下的母离子m/z 167.8,实际为溴硝醇发生反应后的产物2-溴-2-硝基乙醇的分子离子峰。溴硝醇在0~5.0μg/mL浓度范围内呈良好线性,线性相关系数大于0.99,平均回收率为86.2%~94.6%,相对标准偏差不超过13%。该方法适用于大批量粮谷样品中溴硝醇的快速检测。

关键词：高效液相色谱-串联质谱溴硝醇稻谷糙米

Effect of renal sympathetic denervation on atrial substrate remodeling and the inducibility of atrial fibrillation

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Effect of renal sympathetic denervation on atrial substrate ...

中华医学会心电生理和起搏分会第十次全国学术年会

作者： Qingyan Zhao,zixuan Dai,Shengbo yu,XuleWang,Jinping Xiao,Congxin Huang Renmin Hospital of Wuhan University 430060

Objective Whether renal sympathetic denervation has effect on atrial substrate remodeling and inducilibity of AF is unknown. Methods Thirteen dogs were randomly divided into control group(7 dogs) and renal artery ablation(RAA) group(6 dogs).In control group,rapid atrial pacing was performed for 7 hours and atrial effective refractory period(AERP) was measured at every hour in the status of ***, pacing was stopped and AF was induced by atrial burst *** RAA group,each renal artery was ablated via femoral artery and dogs were allowed to recover for 6 *** that,the procedure of pacing and electrophysiological measurement was nearly same as in the control *** of autonomic nerve,Cox43 and ANP in pulmonary veins and atrial tissues were measured and levels of TGF- β,Ang II and aldosterone in blood were studied. Results There was a persistent decrease in AERP in both the two groups during atrial *** cessation of pacing,induced number of times and duration of AF was higher in control group than that in RAA *** plasma AngⅡand aldosterone concentration increased significantly after rapid pacing 7 hours in control group(AngⅡ:119.8±31.1 pg/ml vs 185.3±103.5 pg/ml,P<0.01;Aldosterone: 288.2±43.1 pg/ml vs 369.6±109.8 pg/ml,P=0.01).However,compare with before RAA,the plasma AngⅡand aldosterone concentration decreased significantly after rapid pacing in RAA group(AngⅡ: 159.8±28.2 pg/ml vs 93.1±24.6 pg/ml;Aldosterone:272.2±37.4 pg/ml vs 131.3±53.8 pg/ml,P<0.01). Densities of Cox43 and levels of ANP in RAA group were lower than that in control *** was no significant difference in the densities of autonomic nerve and TGF-P between the two groups. Conclusions Renal sympathetic denervation results in atrial substrate remodeling and markedly decrease the inducilibity of AF by inhibiting activity of RAAS.

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以室点密为中心再探突厥早期史

历史研究 2022年第4期 165-187,224页

作者：孟楷卓于子轩北京大学历史学系北京100871

现行突厥早期史(583年以前)的叙述框架,即土门系、室点密系突厥东西并立说,建立在沙畹对诸种语文文献的错误统合之上。突厥早期史史料可分为三个层次:一是同时代形成的文本;二是后世突厥人的历史记忆;三是以《新唐书·西突厥传》为代表... 详细信息

现行突厥早期史(583年以前)的叙述框架,即土门系、室点密系突厥东西并立说,建立在沙畹对诸种语文文献的错误统合之上。突厥早期史史料可分为三个层次:一是同时代形成的文本;二是后世突厥人的历史记忆;三是以《新唐书·西突厥传》为代表的后世史家的重构。史料批判的结果表明,室点密既不是活跃于突厥西部的Silzibul/Sizabul/Sinjibū,也不是征服西域自立为可汗的西突厥汗国始祖;“泥利国书”中与另一位可汗一同击败柔然的室点密形象则相对可靠。对突厥汗国西部早期历史的考察显示,汗国早期政治结构并非东西并立,而是大可汗独尊于上。

关键词：突厥室点密《新唐书》历史记忆史料批判

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微滴喷射高通量玻璃化细胞保存的实验研究

生物医学工程学杂志 2019年第5期36卷 850-855,861页

作者：喻梓瑄张宵敏周新丽上海理工大学医疗器械与食品学院

血液、干细胞等在临床上的需求量很大,其玻璃化保存面临着要提高降温速率就难以实现高通量这一矛盾问题。本文设计并制作了带容器式收集装置的微滴喷射玻璃化系统,开展了对人肝癌细胞(HepG2)进行高通量玻璃化保存的研究。首先,比较容器... 详细信息

血液、干细胞等在临床上的需求量很大,其玻璃化保存面临着要提高降温速率就难以实现高通量这一矛盾问题。本文设计并制作了带容器式收集装置的微滴喷射玻璃化系统,开展了对人肝癌细胞(HepG2)进行高通量玻璃化保存的研究。首先,比较容器式收集与薄片式接收两种方式对微滴喷射玻璃化保存效果的差异,结果表明容器式收集玻璃化组细胞的存活率和24 h贴壁率明显高于薄片式接收玻璃化组。其次,增加微滴喷射的HepG2细胞密度,发现细胞密度成倍增加时,微滴喷射玻璃化保存效果没有显著变化。最后,将微滴喷射容器式收集玻璃化与慢速冷冻法作比较,容器式收集玻璃化组的细胞处理量增大,且细胞存活率和24 h贴壁率明显高于慢速冷冻组。研究结果表明,本文设计的带容器式收集装置的微滴喷射玻璃化系统不仅能实现细胞的玻璃化保存,而且具有高通量的特点,这对小体积细胞的大体量保存具有重要意义。

关键词：微滴喷射高通量玻璃化