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Achieving Negatively Charged Pt Single Atoms on Amorphous Ni(OH)_(2)Nanosheets with Promoted Hydrogen Absorption in Hydrogen Evolution

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Nano-Micro Letters 2024年第10期16卷 213-224页

作者： Yue Liu Gui Liu Xiangyu Chen Chuang Xue Mingke Sun Yifei Liu jianxin kang Xiujuan Sun Lin Guo School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringKey Laboratory of Bio-inspired Smart Interfacial Science and TechnologyBeihang UniversityBeijing 100191People's Republic of China School of Chemistry Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of EducationXiangtan UniversityXiangtan 411105HunanPeople'Republic of China

Single-atom(SA)catalysts with nearly 100%atom utilization have been widely employed in electrolysis for decades,due to the outperforming catalytic activity and ***,most of the reported SA catalysts are fixed through the strong bonding between the dispersed single metallic atoms with nonmetallic atoms of the substrates,which greatly limits the controllable regulation of electrocatalytic activity of SA *** this work,Pt-Ni bonded Pt SA catalyst with adjustable electronic states was successfully constructed through a controllable electrochemical reduction on the coordination unsaturated amorphous Ni(OH)_(2)nanosheet *** on the X-ray absorption fine structure analysis and first-principles calculations,Pt SA was bonded with Ni sites of amorphous Ni(OH)_(2),rather than conventional O sites,resulting in negatively charged Pt^(δ-).In situ Raman spectroscopy revealed that the changed configuration and electronic states greatly enhanced absorbability for activated hydrogen atoms,which were the essential intermediate for alkaline hydrogen evolution *** hydrogen spillover process was revealed from amorphous Ni(OH)_(2)that effectively cleave the H-O-H bond of H_(2)O and produce H atom to the Pt SA sites,leading to a low overpotential of 48 mV in alkaline electrolyte at-1000 mA cm^(-2)mg^(-1)_(Pt),evidently better than commercial Pt/C *** work provided new strategy for the control-lable modulation of the local structure of SA catalysts and the systematic regulation of the electronic states.

关键词： Hydrogen evolution reaction Amorphous Pt single atoms Hydrogen spillover

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NiS ultrafine nanorod with translational and rotational symmetry

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National Science Review 2024年第07期 218-225页

作者： jianxin kang Qi Hu Ruixuan Zhang Ang Gao Zhongning Huang Ziming Su Ke Pei Qinghua Zhang Li-Min Liu Renchao Che Lin Gu Er-Jia Guo Lin Guo School of Chemistry Beihang University Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative Materials Academy for Engineering&Technology Fudan University Zhejiang Laboratory Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials School of Materials Science and Engineering Tsinghua University Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences School of Physics Beihang University

Anisotropy is a significant and prevalent characteristic of materials, conferring orientation-dependent properties, meaning that the creation of original symmetry enables key functionality that is not found in nature. Even with the advancements in atomic machining, synthesis of separated symmetry in different directions within a single structure remains an extraordinary challenge. Here, we successfully fabricate NiS ultrafine nanorods with separated symmetry along two directions. The atomic structure of the nanorod exhibits rotational symmetry in the radial direction, while its axial direction is characterized by divergent translational symmetry, surpassing the conventional crystalline structures known to date. It does not fit the traditional description of the space group and the point group in three dimensions, so we define it as a new structure in which translational symmetry and rotational symmetry are separated. Further corroborating the atomic symmetric separation in the electronic structure, we observed the combination of stripe and vortex magnetic domains in a single nanorod with different directions, in accordance with the atomic *** manipulation of nanostructure at the atomic level introduces a novel approach to regulate new properties finely, leading to the proposal of new nanotechnology mechanisms.

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Dynamical investigation of tunable magnetism in Au@Ni-carbide nanocrystals by a combined soft and hard X-ray absorption spectroscopy

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Nano Research 2022年第5期15卷 4320-4326页

作者： Weifeng Huang jianxin kang Tingwen Chen Dawei Pang Lihua Wang Hang Wei Changchun Yang Dongfeng Zhang Lin Guo College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China School of Electronic Engineering Jiujiang UniversityJiujiang 332005China School of Chemistry Beihang UniversityBeijing 100191China Institute of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100124China

Nickel based magnetic nanocrystals have been widely applied in magnetic and catalytic *** magnetic properties of nickel can be easily obtained via non-magnetic doping or phase ***,phase transformation from face centered cubic(fcc)to hexagonal close packed(hcp)induced magnetism adjustment of Ni are always confused with nickel carbide(Ni_(3)C),due to the similar atomic structures of hcp-Ni and ***,we present series of Au@Ni-carbide magnetic materials achieved from the controlled carbonation of Au@Ni core-shell structures,whose magnetism is tunable by adjusting the amount of carbon in the Ni ***-situ hard X-ray absorption spectroscopy(XAS)at the metal K edge and soft XAS at both metal L edge and carbon K edge provide solid evidence for the carbonation process from fcc-Ni to Ni_(x)C,rather than phase transformation to *** investigation reveals that the magnetism of the hybrids is mainly contributed from the residual *** result represents an accurate and effective way to distinguish hexagonal Ni_(3)C from hcp-Ni,and provides the pathway to control magnetism of Ni-based materials for applications.

关键词： X-ray absorption spectroscopy soft X-ray absorption spectroscopy carbide nickel carbonation process magnetism

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Highly efficient and recyclable amorphous Pd(II)/crystal Pd(0)catalyst for boosting Suzuki reaction in aqueous solution

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Nano Research 2022年第2期15卷 1193-1198页

作者： Yong Zhao Zhongning Huang Lianmeng Wang Xiangyu Chen Yan Zhang Xiuqin Yang Dawei Pang jianxin kang Lin Guo School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringKey Laboratory of Bio-Inspired Smart interfacial Science and TechnologyBeihang UniversityBeijing 100191China Institute of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing 100124China

Ultrafine and highly dispersed Pd nanoparticles have drawn considerable attention with high activity,selectivity and atomic *** this paper,amorphous Pd(II)-complex solid spheres with-5 nm Pd nanoparticles loaded on were successfully achieved through a simple and gentle one-pot solution method with vitamin B1 simultaneously as complexing agent and reducing *** ultrathin mesoporous SiO_(2) shell was then coated at the surface of Pd(II-O)spheres as the armor which could prevent the dissolution of Pd(II)during the catalytic *** combination of Pd(II)and Pd(0)endowed Pd(II-0)@m-SiO_(2) catalyst an excellent performance in eco-friendly aqueous media Suzuki *** high activity,productivity and recyclability were all comparable with the best Pd catalysts ever *** ingenious formation of amorphous Pd(II)/crystal Pd(0)with enhanced catalytic performances provides a new,scalable strategy to practical promotion of Suzuki cross-coupling reactions.

关键词： palladium amorphous structure supported catalyst mesoporous SiO_(2)shell Suzuki reaction

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Possibility and stabilizing effect of Mo clusters in the Ni-based single-crystal superalloy

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Communications in Theoretical Physics 2024年第8期76卷 187-192页

作者： Yiqun Du Huixin Jin Rongkai kang Boya Zhang Han Wang jianxin Zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China Department of Materials Science and Technology Tokyo University of ScienceTokyo 1258585Japan

Nickel-based single-crystal superalloys are crucial materials for the preparation of aero-engine turbine blades. Many solute elements are added to superalloys for strengthening. However, the relationship between the clustering behavior of solute atoms and the properties of nickel-based single-crystal superalloys is still unclear. Herein, we conduct first-principles calculations onγ phases with Mo-Mo and Mo-Mo-Ru clusters to reveal the possibility and stabilizing mechanism of solute clusters. Introducing Mo lowers the total energy, binding energy, and formation energy of the γ phase due to the replacement of weak Ni-Ni interaction with strong Mo-Ni bonding. Note that the γ phase containing the Mo-Mo cluster is more stable than that containing a Mo single atom, possibly owing to a wide affecting range. The Ru atom added to the γ phase can further boost system stability, and it tends to form a Mo-Mo-Ru cluster. The stabilizing impact of the Mo-Mo-Ru cluster is demonstrated to be the replacement of weak Ni-Mo interaction by the strong Ru-Mo interaction, which may be derived from the enhanced d-orbital hybridization.

关键词： density functional theory superalloys solute cluster

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基于恒电压法的余氯传感器温度补偿研究

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现代科学仪器 2024年第4期41卷 11-15页

作者：周文杰许涛王强廖昌义姜潮杨睿涵康健鑫杭州泽天春来科技股份有限公司浙江杭州310052

我国人均水资源短缺,饮用水的水质管理至关重要,余氯是水质管理中的一项重要指标。相较于DPD比色法测定余氯,恒电压法余氯传感器因具有使用维护方便和响应时间短的优势,普遍应用于自来水、泳池水等水体中余氯含量的在线监测。然而,恒电... 详细信息

我国人均水资源短缺,饮用水的水质管理至关重要,余氯是水质管理中的一项重要指标。相较于DPD比色法测定余氯,恒电压法余氯传感器因具有使用维护方便和响应时间短的优势,普遍应用于自来水、泳池水等水体中余氯含量的在线监测。然而,恒电压法余氯传感器也具有一定的不足,主要是测定结果受测量环境影响较大,特别是温度影响。在探究恒电压法余氯传感器受温度影响的过程中,先结合经典的范德霍夫方程,探究出温度与余氯测量值的关系,并创建了温度补偿算法;然后通过系列实验推算出了温度补偿系数,并验证了该温度补偿算法的合理性与适用性,进一步提高了恒电压法余氯传感器测定余氯的稳定性。促进了余氯在线监测的便捷性,降低了维护成本,拓展了应用范围。

关键词：恒电压法余氯传感器水质温度补偿在线监测

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越野滑雪进哈尔滨中小学校园的可行性分析

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四川体育科学 2020年第1期39卷 119-122页

作者：康建鑫哈尔滨体育学院冬季奥林匹克学院

随着2022年北京冬奥会日益临近,在"让3亿人参加冰雪运动"目标的推广下,冰雪运动在我国得到了空前的发展。其中由于"阳光体育进校园"的大力开展使得各类体育运动可以进入到中小学教学当中,哈尔滨市由于独特的地理位置,越野滑雪运动是该... 详细信息

随着2022年北京冬奥会日益临近,在"让3亿人参加冰雪运动"目标的推广下,冰雪运动在我国得到了空前的发展。其中由于"阳光体育进校园"的大力开展使得各类体育运动可以进入到中小学教学当中,哈尔滨市由于独特的地理位置,越野滑雪运动是该地区中小学校园可以引进的冰雪运动项目之一。通过校园对越野滑雪运动的理论知识宣传推广,强化冰雪课程、场地器材、师资建设等,让学生积极参与越野滑雪运动,并且提高学校间、学校与企业间以及学校与滑雪俱乐部的合作,充分发挥政府相关职能部门的能力,从而加快推进越野滑雪运动进校园的力度。

关键词：哈尔滨越野滑雪运动冬奥会中小学

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高校化学实验室安全分析方法研究

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实验技术与管理 2014年第12期31卷 203-206页

作者：康建新郭丽杰燕山大学环境与化学工程学院河北省应用化学重点实验室河北秦皇岛066004

为确保实验教学和科研工作的顺利进行,必须及时发现和排除化学实验室中各种不安全因素,对于可能存在的安全隐患,及时采取预防措施,防患于未然。建立了高校化学实验室安全检查表,检查表内容包括安全管理、危险化学品管理、仪器设备管理... 详细信息

为确保实验教学和科研工作的顺利进行,必须及时发现和排除化学实验室中各种不安全因素,对于可能存在的安全隐患,及时采取预防措施,防患于未然。建立了高校化学实验室安全检查表,检查表内容包括安全管理、危险化学品管理、仪器设备管理和火灾等重大事故应急管理,并对识别出的危险因素进行风险评价,确定风险等级。为了验证所提出方法的有效性,以燕山大学有机化学实验室为例进行安全分析。结果表明,所提出的方法能有效地辨识出实验室中的危险因素,为实验室安全管理提供了可靠的工具。

关键词：高校化学实验室安全分析安全检查表风险评价

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BP神经网络在实际应用时需注意的几个问题

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新技术新工艺 1999年第1期 5-6页

作者：康建新舒迪前太钢设计院北京科技大学

提出了ＢＰ神经网络在实际应用时需注意的几个问题，有利于提高ＢＰ神经网络的收敛精度和速度，有利于ＢＰ算法在实际中的推广和应用。

关键词：神经网络 BP算法收敛非线性作用函数

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CeO2对镍基碳化钨激光熔覆层组织和耐腐蚀性能的影响

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热加工工艺 2008年第19期37卷 118-120,123页

作者：匡建新汪新衡朱航生湖南工学院机械工程系湖南衡阳421002 衡阳丰顺车桥有限公司产品部湖南衡阳421002

采用Ni60+70wt%镍包碳化钨合金粉末在45钢基材表面进行了激光熔覆。对比研究了添加不同量CeO2在不同激光功率条件下对激光熔覆层的显微组织、裂纹情况、硬度分布及耐腐蚀性能的影响。适量CeO2的加入能使镍基碳化钨金属陶瓷熔覆层组织细... 详细信息

采用Ni60+70wt%镍包碳化钨合金粉末在45钢基材表面进行了激光熔覆。对比研究了添加不同量CeO2在不同激光功率条件下对激光熔覆层的显微组织、裂纹情况、硬度分布及耐腐蚀性能的影响。适量CeO2的加入能使镍基碳化钨金属陶瓷熔覆层组织细化,裂纹大为减少甚至消失,宏观质量得到显著改善。添加适量CeO2的激光熔覆层的耐腐蚀能力比不含CeO2的激光熔覆层要高且显著优于0Cr18Ni9不锈钢。

关键词： CeO2 激光熔覆裂纹微观组织耐腐蚀性

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