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Boron doped 1T phase MoS_(2) as a cocatalyst for promoting photocatalytic H_(2) evolution of g-C_(3)N_(4) nanosheets

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中国化学快报:英文版 2023年第10期34卷 102-105页

作者： pengyuan qiu Yan An Xinyu Wang Shanna An Xiaoli Zhang Jian Tian Wen Zhu School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

As one of the 2D transition metal sulfides,1T phase MoS_(2) nanosheets(NSs)have been studied because of their distinguished conductivity and suitable electronic ***,the active sites are limited to a small number of edge sites only,while the basal plane is catalytically ***,we report that boron(B)doped 1T phase MoS_(2) NSs can replace precious metals as a co-catalyst to assist in photocatalytic H_(2) production of 2D layered g-C_(3)N_(4) nanosheets(g-C_(3)N_(4) NSs).The H_(2) evolution rate of prepared B-MoS_(2)@g-C_(3)N_(4) composites with 15 wt%B-MoS_(2)(B-MoS_(2)@g-C_(3)N_(4)–15,1612.75μmol h^(−1) g^(−1))is 52.33 times of pure g-C_(3)N_(4) NSs(30.82μmol h^(−1) g^(−1)).Furthermore,the apparent quantum efficiency(AQE)of B-MoS_(2)@g-C_(3)N_(4)–15 composites under the light atλ=370 nm is calculated and reaches 5.54%.The excellent photocatalytic performance of B-MoS_(2)@g-C_(3)N_(4)–15 composites is attributed to the B ions doping inducing the distortion of 1T phase MoS_(2) crystal,which can activate more base planes to offer more active sites for H_(2) evolution reaction(HER).This work of B-MoS_(2)@g-C_(3)N_(4) composites offers experience in the progress of effective and low-price photocatalysts for HER.

关键词： 1T phase MoS_(2) g-C_(3)N_(4)nanosheets Photocatalytic H_(2)evolution Active sites Boron doping

The metallic 1T-WS_(2)as cocatalysts for promoting photocatalytic N_(2) fixation performance of Bi_(5)O_(7)Br nanosheets

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Chinese Chemical Letters 2021年第11期32卷 3501-3504页

作者： pengyuan qiu Jianwei Wang Zhangqian Liang Yanjun Xue Yanli Zhou Xiaoli Zhang Hongzhi Cui Guiqing Cheng Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China School of Environmental and Material Engineering Yantai UniversityYantai 264005China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Recently,widespread attention has been devoted to the typical layered BiOCl or BiOBr because of the suitable nanostructure and band ***,owing to the fast carrier recombination,the photocatalytic performance of BiOX materials is not so *** 1T phase WS_(2)nanosheets(NSs)onto Bi_(5)O_(7)Br NSs can improve the photocatalytic N_(2)fixation *** these,the obtained 1T-WS_(2)@Bi_(5)O_(7)Br composites with optimum 5%1T-WS_(2)NSs display a significantly improved photocatalytic N_(2)fixation rate(8.43 mmol L^(−1)h^(−1)g^(−1)),2.51 times higher than pure Bi_(5)O_(7)Br(3.36 mmol L^(−1)h^(−1)g^(−1)).And the outstanding stability of 1T-WS_(2)@Bi_(5)O_(7)Br-5 composites is also ***,the photoexcited electrons from Bi_(5)O_(7)Br NSs are quickly transferred to conductive 1T phase WS_(2)as electron acceptors,which can promote the separation of *** addition,1T-WS_(2)NSs can provide abundant active sites on the basal and edge planes,which can promote the efficiency of photocatalytic N_(2)*** work offers a novel solution to improve the photocatalytic performance of Bi_(5)O_(7)Br NSs.

关键词： Photocatalytic N_(2)fixation Bi_(5)O_(7)Br IT phase WS_(2) Electron-hole pairs Photocatalytic performance

Design of an aircraft autonomous traction taxiing system based on hydraulic secondary control

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Chinese Journal of Aeronautics 2024年第6期37卷 348-359页

作者： Xiaochao LIU Zhongyi qiu Hao ZHANG pengyuan QI Zhenyu WANG Yaoxing SHANG Zongxia JIAO Research Institute for Frontier Science Beihang UniversityBeijing 100083China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Ningbo Institute of Technology Beihang UniversityNingbo 315800China Tianmushan Laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100083China Beijing Tianma Intelligent Control Technology Co. Ltd.Beijing 101399China China Coal Research Institute Beijing 100013China

At present,aircraft taxiing at ground airports needs to be provided with a thrust by the main *** taxiing process is inefficient,has high fuel consumption and serious pollution,and is prone to safety *** this paper,a new configuration of aircraft autonomous traction taxiing system is proposed based on the principle of hydraulic secondary control,in which a hydraulic motor drive device is installed at the front wheels of the aircraft to drive the wheels to rotate forward or *** on this,autonomous taxiing can be realized without relying on the main engines,thus greatly improving airport operation ***,this paper analyzes the influencing factors of the autonomous traction taxiing process,and investigates the parameter matching design of the new configuration ***,this paper develops the ground principle prototype,designs the aircraft longitudinal bonding force observer and the aircraft wheel disturbance moment observer,and proposes the speed control method of the aircraft front wheel autonomous traction taxiing by considering the ground bonding force saturation ***,the ground taxiing test is conducted,and the results show that the new configuration proposed in this paper presents a new solution for aircraft autonomous traction taxiing.

关键词： Autonomous traction taxi-ing Hydraulic secondary control Hydraulic motors Saturation characteristics Disturbance observation Speed control

Cobalt doped Mo5N6 as a noble-metal free novel cocatalyst for promoting photocatalytic hydrogen production of g-C3N4 nanosheets

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Cobalt doped Mo5N6 as a noble-metal free novel cocatalyst fo...

Noble metal-like behavior of plasmonic Bi particles deposited on reduced TiO2 microspheres for efficient full solar spectrum photocatalytic oxygen evolution

第九届新型太阳能材料科学与技术学术研讨会

作者： pengyuan qiu Jian Tian School of Materials Science and Engineering Shandong University of Science and Technology

As one of the 2 D transition metal nitrides, MoN nanosheets(NSs) have been studied because of their excellent conductivity and tunable electronic structure. However, their higher valence state metal ions tend to capture excessive intermediates(H*) in photocatalytic H2 evolution, which leads to poor performance. In this work, we show that Co-doped MoN nanosheets(Co–MoN NSs) could improve the photocatalytic H2 evolution of g-CN nanosheets(NSs). The Co dopant activates the basal plane of MoN by modulating its local electronic structure and exposing more active sites. As a result, the photocatalytic H2 evolution rate reaches 3690.37 mmol hg for Co–MoN/g-CN under simulated sunlight, 119.7, 6.39 and 4.07 times that of g-CN NSs(30.82 mmol hg), MoN/g-CN hybrids(577.54 mmol hg) and Pt/g-CN(907.07 mmol hg), respectively. The apparent quantum efficiency value is 11.23% at λ = 370 nm for Co–MoN/g-CN. DFT calculations show that the loading of Co–MoN provides more catalytic sites on g-CN and reduces the ΔGH* for the HER to promote the HER process.

关键词： Cocatalyst strategies Element doping Graphitic carbon nitride Photocatalytic performance

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Chinese Journal of Catalysis 2020年第2期41卷 333-340页

作者： Hang Zhao Zhangqian Liang Xiang Liu pengyuan qiu Hongzhi Cui Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590ShangdongChina

Herein, novel plasmonic Bi metal in situ deposited in reduced Ti O2 microspheres(Bi@R-Ti O2) are fabricated via a bimetallic MOF-derived synthesized strategy by adjusting the synthesizing temperature. Different characterization techniques, including XRD, SEM, TEM, XPS, DRS, PL, EIS, and photocurrent generation, are performed to investigate the structural and optical properties of the as-prepared samples. The results indicate that the Bi particles are generated inside and outside of reduced Ti O2 microspheres via the reduction of Ti4+ and Bi3+ by ethylene glycol. When the annealing temperature is controlled at 300 o C, the corresponding Bi@R-Ti O2-300 sample with an appropriate amount of Bi nanoparticles exhibits the highest full solar spectrum photocatalytic oxygen evolution activity(4728.709 μmol h–1 g–1), which is 5.9 and 9.5 times higher than that of pure Ti O2 and Bi-Ti bimetal organic frameworks(Bi-Ti-MOFs). Several reasons are suggested for the above results:(1) Bi metal behaves as an "electron acceptor" to accelerate the charge carrier transfer from Ti O2 to Bi;(2) The surface plasmon resonance effect of loaded metallic Bi particles can enhance the visible and NIR light absorption capacity;(3) The generation of Ti3+ further narrows the band gap of TiO2.

关键词： Bi nanoparticles Full solar spectrum O2 evolution Photocatalysis Porous microspheres

Microeukaryotic plankton community dynamics under ecological water replenishment:Insights from eDNA metabarcoding

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Environmental Science and Ecotechnology 2024年第4期20卷 278-290页

作者： Shuping Wang Songsong Gu Yaqun Zhang Ye Deng Wenhui qiu Qianhang Sun Tianxu Zhang pengyuan Wang Zhenguang Yan State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China CAS Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Key Laboratory of Aquatic Genomics Ministry of Agriculture and Rural AffairsBeijing Key Laboratory of Fishery BiotechnologyChinese Academy of Fishery SciencesBeijing100141China College of Resources and Environment University of Chinese Academy of SciencesBeijing100190China Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhen518055China

Ecological water replenishment(EWR)is an important strategy for river restoration globally,but timely evaluation of its ecological effects at a large spatiotemporal scale to further adjust the EWR schemes is of great ***,we examine the impact of EWR on microeukaryotic plankton communities in three distinct river ecosystems through environmental DNA(eDNA)*** three ecosystems include a long-term cut-off river,a short-term connected river after EWR,and long-term connected *** analyzed community stability by investigating species composition,stochastic and deterministic dynamics interplay,and ecological network *** found that EWR markedly reduced the diversity and complexity of microeukaryotic plankton,altered their community dynamics,and lessened the variation within the ***,EWR disrupted the deterministic patterns of community organization,favoring dispersal constraints,and aligning with trends observed in naturally connected *** shift from an isolated to a temporarily connected river appeared to transition community structuring mechanisms from deterministic to stochastic dominance,whereas,in permanently connected rivers,both forces concurrently influenced community *** ecological network in temporarily connected rivers post-EWR demonstrated significantly greater stability and intricacy compared to other river *** shift markedly bolstered the resilience of the ecological *** eDNA metabarcoding insights offer a novel understanding of ecosystem resilience under EWR interventions,which could be critical in assessing the effects of river restoration projects throughout their life cycle.

关键词： Ecological water replenishment Community stability Succession Community assembly mechanism Ecological network

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高重合度人字齿轮轮齿最佳修形优化设计

国防科技大学学报 2015年第1期37卷 165-170页

作者：赵宁秋朋园刘贵立西北工业大学机电学院陕西西安710072

基于斜齿轮轮齿接触分析技术,建立了考虑人字齿轮典型安装误差的抛物线人字齿轮轮齿接触分析方法。综合考虑人字齿轮的传动误差与啮合特性,采用带精英策略的快速非支配排序遗传算法对高重合度人字齿轮的传动性能进行了多目标优化设计,... 详细信息

基于斜齿轮轮齿接触分析技术,建立了考虑人字齿轮典型安装误差的抛物线人字齿轮轮齿接触分析方法。综合考虑人字齿轮的传动误差与啮合特性,采用带精英策略的快速非支配排序遗传算法对高重合度人字齿轮的传动性能进行了多目标优化设计,该算法克服了优化结果的局部收敛,获得了人字齿轮最佳的齿廓、齿向抛物线修形参数。通过实例表明,修形优化后的齿面啮合印痕与传动误差较优化之前得到了明显的改善,有效地改善了高重合度人字齿轮的齿面偏载现象,降低了齿轮传动过程中的啮合冲击。对加工的人字齿轮在减振降噪试验台上进行带载试验,对比优化前后的噪音分贝值,进一步验证了该优化方法对人字齿轮副减振降噪具有一定作用。

关键词：多目标优化人字齿轮轮齿接触分析遗传算法抛物线修形参数噪音

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高重合度人字齿轮传动动态性能优化设计

国防科技大学学报 2015年第2期37卷 166-174页

作者：赵宁秋朋园刘贵立西北工业大学机电学院陕西西安710072

对人字齿轮传动进行高重合度设计的分析,基于人字齿轮副承载接触分析技术,针对人字齿轮传动中主动小齿轮轴向浮动安装的特点,综合考虑齿轮时变啮合刚度、啮合冲击激励及误差激励等因素的影响,采用集中质量法建立了考虑修形的人字齿轮副... 详细信息

对人字齿轮传动进行高重合度设计的分析,基于人字齿轮副承载接触分析技术,针对人字齿轮传动中主动小齿轮轴向浮动安装的特点,综合考虑齿轮时变啮合刚度、啮合冲击激励及误差激励等因素的影响,采用集中质量法建立了考虑修形的人字齿轮副弯-扭-轴耦合非线性振动模型,推导了系统无量纲运动微分方程,求解得到齿轮传动系统的振动加速度。以齿轮的振动加速度均方根值为优化的目标函数,针对该类复杂实际工程优化设计中适应值计算费时的缺点,提出了一种改进的具有适应值预测机制的遗传算法,优化得到了人字齿轮的基本设计参数及修形参数,提高了计算效率,通过实例分析验证了该优化方法的有效性。对加工的人字齿轮在减振降噪试验台上进行带载试验,对比优化前后的噪音分贝值,进一步验证了该优化方法对齿轮副减振降噪具有一定作用。

关键词：人字齿轮高重合度动态性能抛物线修形遗传算法噪音

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同轴面齿轮分扭传动的动态均载特性

西安交通大学学报 2020年第9期54卷 109-116页

作者：李旺赵宁蔺彦虎秋朋园西北工业大学机电学院西安710072 台州学院航空工程学院浙江台州318000

为了解决同轴面齿轮分扭传动在工程应用中的载荷分配不均问题,针对该传动构型不均载机理与动态均载特性展开研究。从功率流的角度分析了同轴面齿轮分扭传动中载荷分配不均问题,基于变形协调基本原理推演了支路载荷分配的过程,指出了影... 详细信息

为了解决同轴面齿轮分扭传动在工程应用中的载荷分配不均问题,针对该传动构型不均载机理与动态均载特性展开研究。从功率流的角度分析了同轴面齿轮分扭传动中载荷分配不均问题,基于变形协调基本原理推演了支路载荷分配的过程,指出了影响载荷分配的主要因素;利用多啮合齿轮系统快速建模方法建立了同轴面齿轮分扭传动系统弯扭轴耦合集中参数齿轮动力学模型,并基于动态啮合力的求解定义了系统动态均载性能的衡量方法;分析了同轴面齿轮分扭传动系统中各齿轮副综合啮合误差,并给出了支路无载传动误差的计算方法;通过算例,研究了支撑刚度与无载传动误差对系统动态均载性能的影响规律。研究结果表明:同轴面齿轮分扭传动不均载产生的本质原因是各支路的刚度及无载传动误差参数不对称;输入齿轮及两惰轮径向支撑刚度对系统均载性能影响较大;调整无载传动误差可以有效地改善系统均载性能。研究结果对同轴面齿轮分扭传动的均载设计具有一定的参考意义。

关键词：面齿轮分扭传动不均载机理均载特性