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Modified Cu active sites by alloying for efficient electrocatalytic reduction CO_(2) to CO

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Journal of Energy Chemistry 2024年第12期99卷 450-457页

作者： Yan Wang Ruikuan Xie Naixuan Ci Zhiyuan Zhu chaoyi li Guoliang Chai Hua-Jun Qiu Yinghe Zhang Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive Application Harbin Institute of TechnologyShenzhen 518055GuangdongChina School of Science Harbin Institute of TechnologyShenzhen 518055GuangdongChina School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen 518055GuangdongChina State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002FujianChina

Transition metals like Au,Ag,and Cu have been reported to be quite active for CO_(2) *** this study,we use density functional theory(DFT)calculation to investigate the electronic structure and catalytic performance of Au,Ag,Cu and their alloys for CO_(2) reduction reaction(CO_(2)RR).Theoretical calculations identified the combination of Ag,Cu,and Au in a face-centered cubic(fcc)alloy as an outstanding electrocatalyst for CO_(2) reduction to CO,with Cu as the active *** d-orbital projected density of state(PDOS)profile suggests that alloying alters the electronic structure of the Cu site,thereby affecting the Gibbs free energy change for the formation of*COOH intermediate(ΔG_(*COOH)).To demonstrate the theoretical prediction experimentally,we employ a top-down dealloying approach to synthesize a nanoporous structured AgCuAu alloy(NP-Ag_(5)Cu_(5)Au_(5)).Electrochemical experiments validate that the ternary alloy catalyst is clearly better than unary and binary catalysts,showing a Faradaic efficiency(FE)for CO over 90%across a broad potential range of 0.6 V,with a peak of approximately 96%at-0.573 V *** study underscores the potential of multi-component alloys in CO_(2)RR and establishes a theoretical basis for designing efficient catalysts for CO_(2) utilization.

关键词： CO_(2)reduction CO Multi-component alloy Nano-porous Electrocatalyst

Submicrosecond electro-optical switching of one-dimensional soft photonic crystals

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Photonics Research 2022年第3期10卷 786-792页

作者： lingling Ma chaoyi li Luyao Sun Zhenpeng Song Yanqing Lu Bingxiang li College of Electronic and Optical Engineering and College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures and College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China

Soft photonic crystals are appealing due to their self-assembly ability,wide tunability,and ***,their response time is relatively slow,ranging from milliseconds to ***,we report submicrosecond switching of chiral liquid crystals(LCs)with 1D photonic microstructures,where electric fields modify the orientational order of molecules and quench their fluctuations,rather than altering the ***,the adjusted refractive indices result in a fast shift of the photonic bandgap,on the order of 100 ns,which is four orders of magnitude faster than conventional electro-optic switching in *** work offers tremendous opportunities for soft photonic applications.

关键词： faster orders refractive

Polymerization enabled reduction of the electrically induced birefringence change in nematic liquid crystals

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Chinese Optics Letters 2022年第2期20卷 172-176页

作者： Jiahao Chen chaoyi li Luyao Sun lingling Ma Bingxiang li Yanqing Lu College of Electronic and Optical Engineering and College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures&College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093China Advanced Materials and liquid Crystal Institute Kent State UniversityKentOH 44242USA

Electric fields modify the optical properties of nematic liquid crystals(NLCs) by changing the nematic molecular orientation or order parameters, which enables electro-optic applications of NLCs. However, the field-induced optic change is undesirable in some cases. Here, we experimentally demonstrate that polymer stabilization weakens the birefringence change of NLCs caused by the nanosecond electrically modified order parameter effect. The birefringence change is reduced by 65% in the NLC doped with 25% reactive monomer, which is polymerized close to the nematic-to-isotropic phase transition. This technique could be used in liquid crystal devices where the birefringence change is unfavored.

关键词： liquid crystal electro-optical response birefringence polymerization

Fixed-time Fault-tolerant Formation Control for Unmanned Surface Vehicles with Actuator Faults

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Fixed-time Fault-tolerant Formation Control for Unmanned Sur...

Finite-time formation control for multiple Underactuated Unmanned Surface Vehicles

第43届中国控制会议

作者： Dezhi Yang Wenzhao Yu Zhe Du chaoyi li Haixiang Xu School of Naval Architecture Ocean and Engine Power EngineeringWuhan University of Technology Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of Education Hainan Institute of Wuhan University of Technology

A fixed-time fault-tolerant formation control method is proposed to achieve rapid formation convergence for multiple unmanned surface vehicles(USVs) in the presence of actuator faults and unknown environmental ***,a fixed-time disturbance observer(FxDO) is designed to estimate and compensate for unknown environmental disturbances and actuator ***,a fixed-time convergent estimator is proposed to observe the time-varying sideslip ***,a fixed-time sliding mode controller(FxSMC) is presented to ensure the fixed-time convergence for the error of the *** effectiveness of the proposed methods is validated through comparative simulation results of three USVs.

关键词： Unmanned surface vehicle Formation control Fixed-time disturbance observer Actuator faults

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Finite-time formation control for multiple Underactuated Unm...

4 × 20 GHz silica-based AWG hybrid integrated receiver optical sub-assemblies

第43届中国控制会议

作者： Houming Huang Wenzhao Yu chaoyi li Zhe Du Haixiang Xu School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of Technology Key Laboratory of High Performance Ship Technology (Wuhan University of Technology) Ministry of Education Hainan Institute of Wuhan University of Technology

This paper focuses on the finite-time formation control of underactuated unmanned surface vehicles(USVs).Aiming at realizing the tracking of multiple USVs,this paper proposes a finite-time guidance control method.A guidance law based on the improved line-of-sight(LOS) method and parameter adaptive technology is designed to enhance tracking *** addition,a composite parameter update law on the basis of graph theory is proposed to facilitate the formation of *** to the theoretical analysis in this paper,the system errors can be converged to zero in finite time under the proposed guidance law,and the simulation experiment also verifies.

关键词： Unmanned surface vehicle Formation control Finite-time convergence Underactuated system

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Chinese Optics Letters 2018年第6期16卷 29-33页

作者： chaoyi li Junming An Jiashun Zhang liangliang Wang Jianguang li Yue Wang Xiaojie Yin Hongjie Wang Yuanda Wu State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100049 China

Both the 4 × 20 GHz coarse wavelength division multiplexing and LAN-WDM receiver optical sub-assemblies（ROSAs） were developed. The ROSA package was hybrid integrated with a planar lightwave circuit arrayed waveguide grating（AWG） with 2% refractive index difference and a four-channel top-illuminated positive-intrinsicnegative photodetector（PD） array. The output waveguides of the AWG were designed in a multimode structure to provide flat-top optical spectra, and their end facet was angle-polished to form a total internal reflection interface to realize vertical coupling with a PD array. The maximum responsivity of ROSA was about 0.4 A/W, and its 3 dB bandwidth of frequency response was up to 20 GHz for each transmission lane. The hybrid integrated ROSA would be a cost-effective and easy-assembling solution for 100 Gb E data center interconnections.

关键词： WDM AWG GHz silica-based AWG hybrid integrated receiver optical sub-assemblies LAN

固相萃取光谱法测定水及肉制品中痕量亚硝酸钠

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食品科学 2021年第12期42卷 309-314页

作者：李超逸李龙朱莹吴婷杜一平华东理工大学上海市功能性材料化学重点实验室上海200237

采用固相萃取光谱法对亚硝酸钠进行定量分析。首先确定分析波长为472.5 nm,随后优化衍生化反应的条件:pH 4.74、衍生化时间15 min、衍生化试剂亚硝酸钠-对氨基苯磺酸-1-萘酚物质的量比1∶3∶3。富集条件:富集膜种类为尼龙膜,过膜体积为1... 详细信息

采用固相萃取光谱法对亚硝酸钠进行定量分析。首先确定分析波长为472.5 nm,随后优化衍生化反应的条件:pH 4.74、衍生化时间15 min、衍生化试剂亚硝酸钠-对氨基苯磺酸-1-萘酚物质的量比1∶3∶3。富集条件:富集膜种类为尼龙膜,过膜体积为10 mL。在0.002~0.030 mg/L质量浓度范围,吸光度y与质量浓度x之间呈二次函数关系,y=-268.76x^(2)+14.55x+0.03,R^(2)=0.999,检出限为1.29μg/L。将该方法用于自来水中亚硝酸钠的检测,加标回收率在91.3%~114.0%之间,相对标准偏差在4.21%~7.90%之间;用于培根亚硝酸钠的检测,检测结果与离子色谱检测结果相符,平行实验的相对标准偏差分别为8.51%、9.98%。本研究为测定亚硝酸钠提供了一种具有较高的灵敏度和选择性,以及较理想的准确度和精密度的新型快速检测方法。

关键词：固相萃取光谱固相萃取漫反射紫外-可见光谱亚硝酸钠快速检测

擘画雅江,水能兴藏——华能积极推进西藏水电开发

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水力发电 2019年第2期45卷 11-13,28页

作者：李超毅常江华能西藏水电安全工程技术研究中心西藏林芝860000

西藏水电开发潜力巨大,华能进入西藏以来,积极推进西藏水电开发,实现科学、有序、绿色、高质量发展,同时响应藏区发展需要,积极承担社会责任。为了促进西藏水电产业健康可持续发展,需要妥善解决电网结构性矛盾,推动水电开发上升为国家战... 详细信息

西藏水电开发潜力巨大,华能进入西藏以来,积极推进西藏水电开发,实现科学、有序、绿色、高质量发展,同时响应藏区发展需要,积极承担社会责任。为了促进西藏水电产业健康可持续发展,需要妥善解决电网结构性矛盾,推动水电开发上升为国家战略,高度重视生态环保问题,开展科技攻关,并建立促进西藏水电可持续发展的优惠政策。未来,西藏水电将在我国电力能源结构调整进程中发挥更为重要的作用,华能为西藏水电事业发展、西藏自治区经济社会跨越式发展作出新的更大的贡献。

关键词：水电开发历程建议前景华能雅鲁藏布江西藏

钯催化的芳基亚磺酸钠的脱硫Heck偶联反应

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精细化工 2021年第1期38卷 124-129页

作者：张胤琳李超逸李惠静吴彦超哈尔滨工业大学海洋科学与技术学院山东威海264209

采用六氟锑酸银为添加剂,实现了钯催化的芳基亚磺酸钠与丙烯酸酯在弱极性溶剂中通过脱硫Heck偶联反应合成肉桂酸酯类化合物。通过核磁共振氢谱、核磁共振碳谱和高分辨质谱对产物进行了结构表征。结果表明,六氟锑酸银活化了钯催化剂,促... 详细信息

采用六氟锑酸银为添加剂,实现了钯催化的芳基亚磺酸钠与丙烯酸酯在弱极性溶剂中通过脱硫Heck偶联反应合成肉桂酸酯类化合物。通过核磁共振氢谱、核磁共振碳谱和高分辨质谱对产物进行了结构表征。结果表明,六氟锑酸银活化了钯催化剂,促进了甲苯中芳基亚磺酸钠与丙烯酸酯的脱硫Heck偶联反应;在空气氛围下的产物收率比在氧气和氮气氛围下的产物收率高。通过反应机理分析发现,氧气不利于三苯基膦配体参与的钯催化剂的再生过程,但有利于醋酸铜氧化剂的再生过程。

关键词：钯催化剂芳基亚磺酸钠 Heck偶联反应六氟锑酸银空气氛围催化技术