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Oxygen modified CoP2 supported palladium nanoparticles as highly efficient catalyst for hydrolysis of ammonia borane

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Nano Research 2022年第4期15卷 3034-3041页

作者： Leijie Zhang Jian Ye Yi Tu Qingyu Wang haibin pan Lihui Wu Xusheng Zheng Junfa Zhu National Synchrotron Radiation Laboratory Department of Chemical Physics and Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesUniversity of Science and Technology of ChinaHefei 230029China School of Science Anhui Agricultural UniversityHefei 230036China

Ammonia borane(AB)is regarded as a promising chemical hydrogen-storage material due to its high hydrogen content,nontoxicity,and long-term stability under ambient temperature.However,constructing advanced catalysts to further promote the hydrogen production still remains a challenge for the hydrolysis of AB.Herein,we report a novel oxygen modified CoP_(2)(O-CoP_(2))material with dispersed palladium nanoparticles(Pd NPs)as a highly efficient and sustainable catalyst for AB hydrolysis.The modification of oxygen could optimize the catalytic synergy effect between CoP_(2)and Pd NPs,achieving enhanced catalytic activity with a turnover frequency(TOF)number of 532 min^(-1)and an activation energy(E_(a))value of 16.79 kJ·mol^(-1).Meanwhile,reaction kinetic experiments prove that the activation of water is the rate-determining step(RDS).The water activation mechanism is revealed by quasi in-situ X-ray photoelectron spectroscopy(XPS)and in-situ X-ray absorption fine structure(XAFS)measurements.The activation of water leads to the production of-H and-OH groups,which are further adsorbed on the oxygen atoms in P-O bond and Pd atoms,respectively.In addition,density functional theory(DFT)calculations indicate that the introduced oxygen facilitates the adsorption and activation of water molecules.This novel modulation strategy successfully sheds new light on the development of advanced catalysts for hydrolysis of AB and beyond.

关键词： Pd-based catalysis ammonia borane hydrolysis water activation quasi in-situ X-ray photoelectron spectroscopy density functional theory(DFT)calculations

Unraveling the advantages of Pd/CeO_(2)single-atom catalysts in the NO+CO reaction by model catalysts

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Nano Research 2023年第7期16卷 8882-8892页

作者： Qian Xu Xingwang Cheng Ningqiang Zhang Yi Tu Lihui Wu haibin pan Jun Hu Honghe Ding Junfa Zhu Yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China

Selective catalytic reduction of NO by CO is challenging in environmental catalysis but attractive owing to the advantage of simultaneous elimination of NO and CO.Here,model catalysts consisting of Pd nanoparticles(NPs)and single-atom Pd supported on a CeO_(2)(111)film grown on Cu(111)(denoted as Pd NPs/CeO_(2)and Pd_(1)/CeO_(2),respectively)were successfully prepared and characterized by synchrotron radiation photoemission spectroscopy(SRPES)and infrared reflection absorption spectroscopy(IRAS).The NO+CO adsorption/reaction on the Pd_(1)/CeO_(2)and Pd NPs/CeO_(2)catalysts were carefully investigated using SRPES,temperature-programmed desorption(TPD),and IRAS.It is found that the reaction products on both model catalysts are in good agreement with those on real catalysts,demonstrating the good reliability of using these model catalysts to study the reaction mechanism of the NO+CO reaction.On the Pd NPs/CeO_(2)surface,N_(2)is formed by the combination of atomic N coming from the dissociation of NO on Pd NPs at higher temperatures.N_(2)O formation occurs probably via chemisorbed NO combined with atomic N on the surface.While on the single-atom Pd_(1)/CeO_(2)surface,no N_(2)O is detected.The 100%N_(2)selectivity may stem from the formation of O-N-N-O^(*)intermediate on the surface.Through this study,direct experimental evidence for the reaction mechanisms of the NO+CO reaction is provided,which supports the previous density functional theory(DFT)calculations.

关键词： NO+CO reaction Pd/CeO_(2) model catalysts reaction mechanisms

Theoretical calculations on the atomic and electronic structure of β-SiC(110) surface

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Chinese Science Bulletin 2002年第10期47卷 804-809页

作者： Changkun Xie Pengshou Xu Faqiang Xu haibin pan Structure Research Laboratory University of Science & Technology of China Hefei China National Synchrotron Radiation Laboratory University of Science & Technology of China Hefei China

We present a theoretical calculation of the atomic and electronic structure of β-SiC and its non-polar (110) surface using the full potential linear augmented plane wave (FPLAPW) approach. The calculated lattice constant and bulk modulus of p-SiC crystal are in excellent agreement with experimental data. The atomic and electronic structure of β-SiC(110) surface has been calculated by employing the slab and supercell model. It is found that the surface is characterized by a top-layer bond-length-contracting rotation relaxation in which the Si-surface atom moves closer towards the substrate while the C-surface atom moves outward. This relaxation is analogous to that of Ⅲ-Ⅴ semiconductor surface. The driving mechanism for this atomic rearrangement is that the Si atom tends to a planar sp2-like bonding situation with its three N neighbors and the N atom tends to a p3-like bonding with its three Si neighbors. Furthermore, surface relaxation induces the change from metallic to semiconducting

关键词： SiC FPLAPW method surface atomic structure surface electronic structure.

同时测定复方阿胶浆中间体中17种化学成分的定量核磁方法

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中草药 2024年第5期55卷 1532-1540页

作者：谢欣媛杨嘉誉潘坚扬瞿海斌浙江大学药物信息学研究所浙江杭州310058

目的建立定量核磁方法,同时测定复方阿胶浆(Compound E’jiao Jiang,CEJ)的药材提取液中多类成分的含量,为中间体的质量评价提供可靠的分析手段。方法采用水信号预饱和脉冲序列Noesygppr1d采集样品的1H-NMR图谱。通过文献调研、数据库... 详细信息

目的建立定量核磁方法,同时测定复方阿胶浆(Compound E’jiao Jiang,CEJ)的药材提取液中多类成分的含量,为中间体的质量评价提供可靠的分析手段。方法采用水信号预饱和脉冲序列Noesygppr1d采集样品的1H-NMR图谱。通过文献调研、数据库检索以及加标实验的方式进行核磁谱峰归属。进一步确定各化合物的定量峰,采用内标法定量。开展方法学考察,考察项包括线性、精密度、稳定性、重复性、耐用性、准确度。另基于核磁共振氢谱的信噪比确定方法的检测限和定量限,并对3批中间体样本进行分析。结果共指认22种化合物,其中17种可同时定量分析,包括缬氨酸、丙氨酸、异亮氨酸、焦谷氨酸、γ-氨基丁酸5种氨基酸,乙酸根、富马酸根、丙酮酸根、琥珀酸根、甲酸根、乳酸6种小分子有机酸根,葡萄糖、果糖、半乳糖、蔗糖4种糖类以及尿苷、胆碱。线性考察结果得出相关系数均不小于0.9995,精密度考察结果显示,RSD均小于2.7%,重复性考察RSD均小于2.5%,耐用性及稳定性考察RSD均小于2.6%,加样回收实验得出平均回收率为90.0%~105.0%、RSD小于2.2%,分析值与参考值平均相对偏差小于4.0%。对3批样品进行定量分析,17种成分的测定结果均高于定量限,且满足线性范围。3批样品可定量部分占总固体含量的质量分数分别为71.09%、84.44%、70.09%。结论各方法学考察均满足要求;研究开发的定量核磁方法检测时间短、制样方式简单,能有效提高分析效率,为CEJ的生产过程物质转移规律研究打下基础。

关键词：核磁共振 1H-qNMR 定量方法多类成分复方阿胶浆质量评价缬氨酸丙氨酸异亮氨酸焦谷氨酸 γ氨基丁酸乙酸根富马酸根丙酮酸根琥珀酸根甲酸根乳酸葡萄糖果糖半乳糖蔗糖尿苷胆碱

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连续自翻浸输送系统在汽车制造中的应用

机械制造 2024年第2期62卷 67-71页

作者：潘海滨东杰海登(常州)科技有限公司江苏常州213000

给出了连续自翻浸输送系统的线路布局与工艺流程,分析了运行原理与特点。以汽车涂装车间前处理电泳线为例,介绍连续自翻浸输送系统在汽车制造中的应用,包括系统组成、技术参数和电气程序调试。

关键词：自翻浸输送汽车制造应用

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车身编组存储立体库的设计和应用

机械制造 2024年第3期62卷 15-18页

作者：潘海滨东杰海登(常州)科技有限公司江苏常州213000

对车身编组存储立体库的关键设计参数进行了介绍,对平面布局和工艺流程进行了论述,并对钢结构立体货架、双立柱巷道式堆垛机、塑料板带横移机等结构进行了分析和参数计算,同时介绍了其它机械化输送设备和电气控制。

关键词：车身编组存储设计应用

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Grain boundaries modulating active sites in RhCo porous nanospheres for efficient CO2 hydrogenation

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Nano Research 2018年第5期11卷 2357-2365页

作者： Xusheng Zheng Yue Lin haibin pan Lihui Wu Wei Zhang Linlin Cao Jing Zhang Lirong Zheng Tao Yao National Synchrotron Radiation Laboratory University of Sdence and Technology of China Hefei 230029China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Hefei 230026 China Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Designing active sites and engineering electronic properties of heterogeneous catalysts are both promising strategies that can be employed to enhance the catalytic activity for CO2 hydrogenation. Herein, we report RhCo porous nanospheres with a high density of accessible grain boundaries as active sites for improved catalytic performance in the hydrogenation of CO2 to methanol. The porous nanosphere morphological feature allows for a high population of grain boundaries to be accessible to the reactants, thereby providing sufficient active sites for the catalytic reaction. Moreover, in-situ X-ray photoelectron spectroscope （XPS） results revealed the creation of negatively charged Rh surface atoms that promoted the activation of CO2 to generate CO2^6- and methoxy intermediates. The obtained RhCo porous nanospheres exhibited remarkable low-temperature catalytic activity with a turnover frequency （TOFRh） of 612 h^-1, which was 6.1 and 2.5 times higher than that of Rh/C and RhCo nanoparticles, respectively. This work not only develops an efficient catalyst for CO2 hydrogenation, but also demonstrates a potential approach for the modulation of active sites and electronic properties.

关键词： carbon dioxide,rhodium,cobalt,grain boundaries,charge transfer,hydrogenation

端面薄膜法布里-珀罗腔光纤动态压力传感器仿真与实验研究

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光学学报 2024年第7期44卷 227-235页

作者：张雄星孙哲赵学庆高子皓冯晓军潘文陈海滨西安工业大学光电工程学院陕西西安710021 西北核技术研究所陕西西安710024 西安近代化学研究所陕西西安710065

为实现冲击波动态信号的测量,研制了一种光纤端面镀金-派瑞林-金三层结构的薄膜式光纤法布里-珀罗压力传感器。对该传感器进行了理论分析与仿真,搭建了静态和动态压力测量系统,并对其进行测试与分析。结果表明:在0~60 MPa的静态压力测... 详细信息

为实现冲击波动态信号的测量,研制了一种光纤端面镀金-派瑞林-金三层结构的薄膜式光纤法布里-珀罗压力传感器。对该传感器进行了理论分析与仿真,搭建了静态和动态压力测量系统,并对其进行测试与分析。结果表明:在0~60 MPa的静态压力测量范围内,传感器的波长灵敏度和腔长灵敏度分别为0.0809 nm/MPa和0.3200 nm/MPa,与仿真结果一致;在动态压力测量中,传感器成功捕捉到了压力峰值为7.41 MPa和上升时间为75 ns的冲击波信号。

关键词：光纤传感器法布里-珀罗腔薄膜压力测量

^(1)H-NMR定量测定黄芪注射液中亲水性成分和疏水性成分

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中草药 2024年第10期55卷 3321-3330页

作者：杨嘉誉徐绍静张琪应旭辉李文竹潘坚扬瞿海斌浙江大学药学院药物信息学研究所浙江杭州310058 正大青春宝药业有限公司浙江杭州310023

目的建立黄芪注射液中亲水性成分和疏水性成分的^(1)H-NMR定量分析方法。方法以10%氘代水(10%D2O)和氘代甲醇(CD3OD)为氘代溶剂制备黄芪注射液亲水性成分和疏水性成分的^(1)H-NMR样品。使用Bruker Avance Ⅲ 600型核磁共振波谱仪采集^(1... 详细信息

目的建立黄芪注射液中亲水性成分和疏水性成分的^(1)H-NMR定量分析方法。方法以10%氘代水(10%D2O)和氘代甲醇(CD3OD)为氘代溶剂制备黄芪注射液亲水性成分和疏水性成分的^(1)H-NMR样品。使用Bruker Avance Ⅲ 600型核磁共振波谱仪采集^(1)H-NMR图谱,具体实验参数如下:Noesygppr1D脉冲序列;温度为298 K,数据点32 K,采集时间(AQ)为2.980 s,脉冲宽度(SW)为7211.54 Hz,弛豫延迟时间(D1)分别为15.0 s和20.0 s,频率偏移(O1)分别为2816.65 Hz和2930.31 Hz,接收器增益(RG)值为57,扫描次数(NS)32次。结果在^(1)H-NMR图谱中归属出33种成分,分别是异亮氨酸、亮氨酸、缬氨酸、丙氨酸、乳酸、焦谷氨酸、天冬酰胺、γ-氨基丁酸、脯氨酸、甲酸、乙酸、富马酸、苹果酸、琥珀酸、丙二酸、蔗糖、果糖、半乳糖、葡萄糖、胆碱、甜菜碱、葫芦巴碱、尿苷、腺苷、胞苷、鸟苷、腺嘌呤、黄芪皂苷Ⅲ、黄芪甲苷、芒柄花苷、毛蕊异黄酮苷、9,10-二甲氧基紫檀烷-3-O-葡萄糖苷以及异黄烷苷。对其中27种化学成分(异亮氨酸、缬氨酸、丙氨酸、乳酸、焦谷氨酸、天冬酰胺、γ-氨基丁酸、脯氨酸、甲酸、乙酸、富马酸、苹果酸、琥珀酸、丙二酸、蔗糖、果糖、葡萄糖、胆碱、甜菜碱、葫芦巴碱、尿苷、腺苷、鸟苷、腺嘌呤、黄芪皂苷Ⅲ、黄芪甲苷、毛蕊异黄酮苷)进行定量,可定量的成分占注射液固含量90%以上。该方法的精密度、重复性、样品稳定性和耐用性良好,各个成分线性关系良好,r 2大于0.9990,加样回收回收率为98.19%~101.40%。结论建立了一种简单、快速、可靠的^(1)H-NMR定量方法用于测定黄芪注射液中的亲水性成分和疏水性成分,为黄芪注射液的质量评价提供了新的分析手段。

关键词：质子核磁共振黄芪注射液含量测定中药注射剂亲水性成分疏水性成分 ^(1)H-NMR定量分析方法异亮氨酸缬氨酸丙氨酸乳酸焦谷氨酸天冬酰胺 γ-氨基丁酸脯氨酸甲酸乙酸富马酸苹果酸琥珀酸丙二酸蔗糖果糖葡萄糖胆碱甜菜碱葫芦巴碱尿苷腺苷鸟苷腺嘌呤黄芪皂苷Ⅲ 黄芪甲苷毛蕊异黄酮苷