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Journal of Energy Chemistry 2023年第5期80卷 58-67,I0003页

作者： Kai Zhang Zixiang Zhan Minzhi Zhu Haiwei Lai Xiangyang He weiping Deng Qinghong Zhang Ye Wang state Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsInnovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Selective oxidation of biomass and its derivatives to dicarboxylic acids represents a promising route for biomass ***,the co-presence of multiple functional groups in biomass molecules makes the selective oxidation of particular functional a challenging ***,we demonstrate an efficient electrocatalytic system consisting of nickel oxide(NiO)and a nitroxyl radical,i.e.,2,2,6,6-tetrame thylpiperidine-1-oxyl(TEMPO)or 4-acetamido-TEMPO(ACT),for the selective oxidation of key bioplatform molecules including glucose,xylose and 5-hydroxymethylfurfural(HMF)into corresponding dicarboxylic acids,i.e.,glucaric acid,xylaric acid,and 2,5-furandicarboxylic acid(FDCA).NiO is clarified as the active catalyst for the oxidation of aldehyde in bio-platform molecules to carboxylic acid,while TEMPO or ACT is responsible for the oxidation of primary alcohol to *** combination of NiO and TEMPO or ACT significantly accelerated the tandem oxidation of aldehyde and hydroxyl groups in glucose,xylose and HMF,thus achieving excellent yields(83%-99%)of dicarboxylic ***,the combination catalyst enables the selective oxidation of glucose and xylose with high concentrations(e.g.,20 wt%),which offers a promising strategy for biomass valorization.

关键词： Biomass Electrocatalysis Nio Nitroxyl radical Dicarboxylic acid

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全膜脉冲电容器电热老化分析

强激光与粒子束 2024年第2期36卷 145-151页

作者：黄云祺王凌云张东东陈林袁建强谢卫平邓明海孔佑军大连理工大学电气工程学院辽宁大连116024 中国工程物理研究院流体物理研究所四川绵阳621900 天府创新能源研究院成都610000 国网综合能源服务集团有限公司北京100052

全膜脉冲电容器是脉冲功率系统的重要储能单元,其寿命影响着整个系统的可靠性。在脉冲工况下,全膜脉冲电容器的失效多为突发失效,且寿命的分散性较大。为探究全膜脉冲电容器老化失效机理,开展了其寿命试验及电场与温度场的仿真。利用LT... 详细信息

全膜脉冲电容器是脉冲功率系统的重要储能单元,其寿命影响着整个系统的可靠性。在脉冲工况下,全膜脉冲电容器的失效多为突发失效,且寿命的分散性较大。为探究全膜脉冲电容器老化失效机理,开展了其寿命试验及电场与温度场的仿真。利用LTD基本放电单元(Brick)实验腔体对电容器进行寿命测试并获得失效电容器,分析了失效电容在不同故障形式下的失效原因,并利用有限元分析软件对电容器局部“电场易畸变”区域进行了电场仿真,说明上述区域存在的畸变电场是发生绝缘介质击穿的主要原因;对电容器进行温度场分析,发现电容器温度与充放电频率成正相关,温度最高点位于电容器几何中心处附近,在充放电频率较低时,电容器温升不明显,说明在较低充放电频率下,电容器绝缘介质老化以电老化为主,而非热老化。

关键词：全膜脉冲电容器寿命试验老化电场畸变失效机理

Quantum optical devices based on four-wave mixing in hot rubidium vapor

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Science China(Physics,Mechanics & Astronomy) 2015年第6期58卷 47-54页

作者： FANG YaMi QIN ZhongZhong WANG HaiLong CAO LeiMing XIN Jun FENG JingLiang ZHANG weiping JING JieTai state Key Laboratory of Precision Spectroscopy Quantum Institute for Light and AtomsDepartment of PhysicsEast China Normal University

In this paper,we briefly review the recent experimental progresses in quantum optics based on four-wave mixing(FWM) processes in hot rubidium vapor,particularly our two recent experiments in quantum *** have experimentally produced strong quantum correlations between three bright beams generated by two cascaded FWM *** intensity difference squeezing with the cascaded system is enhanced to(-7.0±0.1)d B from the(-5.5±0.1)d B/(4.5±0.1)d B with only one FWM ***,this system can be easily extended to multiple modes using multiple FWM ***,we have also successfully realized a cascade all-optical transistor(AOT),which is driven by a very weak light beam about 800 photons in *** required probe power for achieving a switching efficiency of 50% can be as low as 180 p W,and it can manipulate a light beam with power of 5.0×106 times more,which proves the cascade of the *** experiments may find wide applications in quantum information and optical communication.

关键词： four wave mixing quantum correlations all-optical transistor quantum information and optical communication

Improvement of low temperature activity and stability of Ni catalysts with addition of Pt for hydrogen production via steam reforming of ethylene glycol

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Green Energy & Environment 2019年第3期4卷 300-310页

作者： Xingling Zhao Kai Wu weiping Liao Yingxiong Wang Xiaoning Hou Mingshan Jin Zhanghuai Suo Hui Ge Institute of Applied Catalysis Yantai University30 Qingquan RoadYantai 264005ShangdongChina state Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina

Hydrogen production by steam reforming of ethylene glycol(EG) at 300℃ was investigated over SiO2 and CeO2 supported Pt–Ni bimetallic catalysts prepared by incipient wetness impregnation methods. It was observed that impregnation sequence of Pt and Ni can affect the performance of catalysts apparently. Catalyst with Pt first and then Ni addition showed higher EG conversion and H2 yield owing to the Ni enrichment on the surface and the proper interaction between Pt and Ni. It was observed that although SiO2 supported catalysts exhibited better activity and H2 selectivity, CeO2 supported ones had better stability. This is attributed to the less coke formation on CeO2. Increasing Pt/Ni ratio enhanced the reaction activity, and Pt3–Ni7 catalysts with 3 wt% Pt and 7 wt% Ni showed the highest activity and stability. Ni surficial enrichment facilitated the C-C bond rupture and water gas shift reactions;and Pt addition inhibited methanation reaction. Electron transfer and hydrogen spillover from Pt to Ni suppressed carbon deposition. These combined effects lead to the excellent performance of Pt3–Ni7 supported catalysts.

关键词： Ethylene glycol Steam reforming Pt–Ni bimetallic catalyst Hydrogen production Synergistic effect

水稻种质资源萌发期耐旱性评价及耐旱种质筛选

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杂交水稻 2024年第4期39卷 27-35页

作者：黄一轩刘雪严圣杰黎妮张先文刘志王伟平湖南农业大学生物科学技术学院湖南长沙410128 湖南杂交水稻研究中心湖南长沙410125 杂交水稻全国重点实验室湖南长沙410125

为探索水稻早期耐旱性鉴定方法,筛选耐旱水稻种质资源,选择4份耐旱能力有差异的水稻材料,分析其种子萌发能力在不同浓度PEG-6000模拟干旱胁迫处理下的变化,确定最适处理浓度为20%;然后以该处理浓度对26份水稻材料进行萌发试验,采用主成... 详细信息

为探索水稻早期耐旱性鉴定方法,筛选耐旱水稻种质资源,选择4份耐旱能力有差异的水稻材料,分析其种子萌发能力在不同浓度PEG-6000模拟干旱胁迫处理下的变化,确定最适处理浓度为20%;然后以该处理浓度对26份水稻材料进行萌发试验,采用主成分分析方法,明确以相对发芽势、相对发芽率、相对苗高、相对根长、萌发耐旱指数及活力指数作为耐旱评价指标,并利用平均总隶属函数和系统聚类的方法综合评价耐旱能力,筛选出高抗旱材料20H022,抗旱材料20H100、20H152、20H263和非洲陆稻;进一步以鉴定的6份抗旱能力不同的材料(20H022、20H100、20H195、20H066、非洲陆稻、日本晴)在苗期进行干旱模拟胁迫,较好地验证了萌发期耐旱性分级结果。本研究有助于水稻种质耐旱性的早期快速鉴定,为耐旱育种提供材料和鉴定方法。

关键词：水稻耐旱性种子萌发期筛选方法

Optomechanical preparation of photon number-squeezed states with a pair of thermal reservoirs of opposite temperatures

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Photonics Research 2023年第9期11卷 I0001-I0009页

作者： BAIQIANG ZHU KEYE ZHANG weiping ZHANG state Key Laboratory of Precision Spectroscopy Department of PhysicsSchool of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China Shanghai Branch Hefei National LaboratoryShanghai 201315China School of Physics and Astronomy and Tsung-Dao Lee InstituteShanghai Jiao Tong UniversityShanghai 200240China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Photon number-squeezed states are of significant value in fundamental quantum research and have a wide range of applications in quantum *** of their preparation mechanisms require precise control of quantum dynamics and are less tolerant to *** propose a mechanism that is not subject to these *** contrast to common approaches,we exploit the self-balancing between two types of dissipation induced by positive-and negative-temperature reservoirs to generate steady states with sub-Poissonian statistical distributions of photon *** also show how to implement this mechanism with cavity optomechanical *** quality of the prepared photon number-squeezed state is estimated by our theoretical model combined with realistic parameters for various typical optomechanical systems.

关键词： preparation quantum squeezed

Programmed co-assembly of DNA-peptide hybrid microdroplets by phase separation

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Chinese Chemical Letters 2022年第3期33卷 1545-1549页

作者： Shengtao Yao Yue Liao Rizhao Pan weiping Zhu Yufang Xu Yangyang Yang Xuhong Qian School of Pharmacy Shanghai Key Laboratory of Chemical BiologyEast China University of Science and TechnologyShanghai 200237China state Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai 200237China

Biopolymers, including DNA and peptides have been used as excellent self-assembling building blocks for programmable single-component or hybrid materials, due to their controlled molecular ***, combining two assembling principles of DNA-based programmability and peptide-based specific molecular interactions for hybrid structures to microscale has not yet been achieved. In this study,we describe a hybrid microsystem that emerges from the co-assembly of DNA origami structure and short elastin-like polypeptide conjugated oligonucleotides, and initiates liquid-liquid phase separation to generate microdroplets upon heating above the transition temperature. Moreover, the hybrid microdroplets are capable for guest molecule trapping and perform bi-/tri-enzymatic cascades with rate enhancements as open “microreactors”. Our programmed assembled DNA-peptide microsystem represents a new combination of DNA nanotechnology and peptide science and opens potential application routes toward lifeinspired biomaterials.

关键词： Self-assembly Microdroplet DNA origami Phase separation Elastin-like polypeptides

A highly sensitive fluorescent probe for tracking intracellular zinc ions and direct imaging of prostatic tissue in mice

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Chinese Chemical Letters 2020年第11期31卷 2933-2936页

作者： Yuyu Wang Houna Duan Hongyuan Shi Shiwei Zhang Yufang Xu weiping Zhu Xuhong Qian state Key Laboratory of Bioreactor Engineering Shanghai Key Laboratory of Chemical BiologySchool of PharmacyEast China University of Science and TechnologyShanghai 200237China Department of Radiology Jiangsu Province HospitalFirst Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

A highly sensitive fluorescent sensor ZnDN was designed,synthesized and used for tracking intracellular zinc ions in various living cells and direct imaging of prostatic tissue in *** was prepared from the heterocyclic-fused naphthalimide fluorophore,and the zinc receptor,N,N-bis(2-pyridylmethyl)ethylenediamine(BPEN).Upon addition of Zn2+to the solutions of ZnDN,a remarkable fluorescence enhancement was observed,which could be attributed to the photo-induced electron transfer(PET)*** ZnDN exhibited high sensitivity toward Zn2+in phosphate buffer solution,with a limit of detection of 4.0 x 10-9 mol/L,it was further applied for the imaging of exogenous and endogenous Zn21 in different living *** cells imaging experiments suggested that ZnDN could image the changes of intracellular free zinc ions,and could be used for two-photon ***,flow cytometry suggested that ZnDN could distinguish cancerous prostate cells from normal *** experiments indicated that ZnDN had the potential in imaging prostate tissue in vivo.

关键词： Fluorescent probe Zinc ion Prostate cells Naphthalimide In vivo imaging

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基于自适应预设性能的运载火箭姿态容错控制

飞控与探测 2024年第4期7卷 54-65页

作者：杨宇豪王忠森许炜平廖宇新中南大学自动化学院长沙410083 中南大学航空航天技术研究院长沙410083 湖南大学电气与信息工程学院长沙410083

针对存在模型不确定性、外部环境干扰及执行机构故障的运载火箭姿态容错控制问题,提出了一种自适应预设性能容错控制方法。首先,基于运载火箭姿态运动模型、执行机构故障模型及姿态跟踪误差模型,建立了运载火箭容错控制数学模型;然后,... 详细信息

针对存在模型不确定性、外部环境干扰及执行机构故障的运载火箭姿态容错控制问题,提出了一种自适应预设性能容错控制方法。首先,基于运载火箭姿态运动模型、执行机构故障模型及姿态跟踪误差模型,建立了运载火箭容错控制数学模型;然后,利用级联扩张状态观测器对总扰动进行观测补偿,并针对故障可能造成姿态跟踪误差突变的问题提出了一种固定时间收敛的自适应预设性能函数,设计了预设性能反步控制律,证明了闭环控制系统的稳定性;最后,通过数值仿真验证了该控制方法能在执行机构故障情况下确保姿态跟踪误差满足预设性能指标。

关键词：运载火箭容错控制执行机构故障预设性能控制级联扩张状态观测器

Facile shape and size-controlled growth of uniform magnetite and hematite nanocrystals with tunable properties

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Science China Chemistry 2011年第6期54卷 923-929页

作者： CHEN LiQiao LIU weiping CHEN JiaLin YANG XianFeng LIU Jia FU XiongHui WU MingMei Key Laboratory of Bioinorganic and Synthetic Chemistry Ministry of Education' State Key Laboratory of Optoelectronic Materials and Technologies' School of Chemistry and Chemical Engineering Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China state Key Lab of Advanced Technology for Comprehensive Utilization of Platinum Metals ' Kunming Institute of Precious Metals Kunming 650106 China

Monodispersed magnetite Fe3O4 and hematite α-Fe2O3 nanocrystals have been grown in co-solvents of alcohol and water. Either the shape or the size of the nanocrystals could be easily controlled. Both the phases and nanostructures have been characterized by powder X-ray diffraction patterns and electron microscopy. The magnetic and catalytic properties of these products were investigated and compared with each other. The obtained results clearly demonstrate that these iron oxide nanocrystals are soft ferromagnetic at room temperature and α-Fe2O3 has a more effective catalytic property on the thermal decomposition of ammonium perchlorate than Fe3O4. Based on the experimental data, it is proposed that the magnetic and catalytic properties of these nanocrystals are dependent not only on the size and shape, but also on the surface structure of the nanocrystals. The nanoplates with significant anisotropic nanostructure demonstrate a highly enhanced performance as compared to nanoparticles.

关键词： iron oxide nanocrystals growth properties