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Nano Research 2024年第7期17卷 6534-6543页

作者： Ya-Chuan Liang qing cao Yuan Deng Yong Wang Kai-Kai Liu Chong-Xin Shan School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002China Henan Key Laboratory of Diamond Optoelectronic Material and Devices Key Laboratory of Material PhysicsMinistry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China Institute of Quantum Materials and Physics Henan Academy of SciencesZhengzhou 450046China

Easy non-radiative decay property of long-lived triplet excitons in aqueous solution obstructs their applications in aquatic *** reported phosphorescence phenomena in aqueous solution have excited researchers enormously but achieving full-color water-soluble phosphorescent carbon nanodots(CNDs)is still a challenging ***,full-color phosphorescence of water-soluble CNDs has been demonstrated by triggering their triplet excitons through nanospace domain confinement,and Förster energy resonance transfer is used for further tuning phosphorescence *** phosphorescence spans across most of the visible spectrum,ranging from 400 to 700 *** an aqueous solution,the CNDs exhibits blue,green,and red phosphorescence,lasting for approximately 6,10,and 7 s,***,the phosphorescence quantum yields are 11.85%,8.6%and 3.56%,making them readily discernible to the naked eyes and laying a solid foundation for practical ***,phosphorescence flexible optical display and bioimaging have been demonstrated by using the multicolor CNDs-based nanomaterials,showing distinct superiority for accuracy and complete display and imaging in complex emission background.

关键词： carbon nanodots triplet excitons multicolor aqueous solution

Unraveling role of double-exchange interaction in electrochemical water oxidation by external magnetic field

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Rare Metals 2024年第1期43卷 289-297页

作者： Jun Li Jun-Ming Li Hong Hong Dong-Xue Liu qing-Qi cao Dun-Hui Wang National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology Nanjing UniversityNanjing 210093China School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

Double-exchange(DE) interaction plays an important role in electrocatalytic oxygen evolution reaction(OER).However,precise achievement of DE interaction often requires foreign dopants or vacancy engineering,leading to destabilization of the catalysts and deterioration of *** contrast,the utilization of environmentally friendly,contactless,and continuously adjustable magnetic fields to study the OER process is profitable to avoid aforementioned interference factors and further elucidate the direct relationship_(0.5)between DE interaction and OER ***,by using cobalt hydroxide carbonate(Co(OH)(CO_(3))·xH_(2)O,CoHC) nanostructures as a proof-of-concept study,external magnetic fields are carefully implemented to verify the role of DE interaction during water oxidation *** studies reveal that external magnetic fields effectively enhance the reaction rate of the catalyst,the overpotential decreases from 386 to 355 mV(100 mA·cm^(-2)),while Tafel slopes drastically decline from 93 to 67 mV·dec^(-1)(1.0 T).Moreover,magnetic field increment exhibits robust *** in situ Raman and impedance measurements under external field,it can be found that magnetic field promotes the electron migration between Co^(2+) and Co^(3+) in the CoHC catalysts with the assistance of DE interactions,thus boosting the OER efficiency.

关键词： Magnetic field Double-exchange(DE)interaction Electrocatalysis Oxygen evolution reaction(OER) Cobalt hydroxide carbonate

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： Zhen-bing CAI Chun-lin LI Lei YOU Xu-dong CHEN Li-ping HE Zhong-qing cao Zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

Enhanced hydrogen evolution reaction in FePt film with remanence due to decrease in domain walls

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Rare Metals 2024年第3期43卷 1108-1115页

作者： Hong Hong Dong-Xue Liu Jun Li Jun-Ming Li Li-Qian Wu Bo Yang qing-Qi cao Dun-Hui Wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing210093China Hangzhou Dianzi University Hangzhou310018China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang110819China

As an effective strategy to improve the properties of electrocatalysts,magnetic field-assisted electrocatalytic water splitting has attracted increasing attention ***,the corresponding enhancements mostly depend on the exertion of an external magnetic field during electrochemical reactions,which results in a high cost of industrial production,and makes the magnetic field manipulation of electrocatalysis become a challenging *** this work,instead of the external magnetic field,a bias magnetic field is self-supplied by the remanence state of a ferromagnetic electrocatalyst of *** to the assistance of this bias magnetic field,the FePt film in the remanence state shows the overpotential of 229 mV during hydrogen evolution reaction,which is much lower than that in its demagnetization state(283 mV).Our findings demonstrate that the remanence in ferromagnetic electrocatalysts can improve the catalytic performance,which is attributed to the decrease in domain walls.

关键词： Remanence Magnetic domains Electrocatalysis Hydrogen evolution reaction(HER)

Orientation controlled photogenerated carriers on selfsupporting CdS/Ni_(3)S_(2) paper toward photocatalytic hydrogen evolution and biomass upgrading

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Rare Metals 2024年第5期43卷 2015-2025页

作者： Xiao-Yan Liu qing cao Gui-Xiang Li Hui Liu Li-Li Zeng Li-Li Zhao Bin Chang Xi-Wen Wang Hong Liu Wei-Jia Zhou Institute for Advanced Interdisciplinary Research School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Institute of Chemical Sciences and Engineering Ecole Polytechnique Federale de Lausanne1015LausanneSwitzerland KAUST Catalysis Center King Abdullah University of Science and TechnologyThuwal 23955-6900Kingdom of Saudi Arabia School of Environment and Energy South China University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China State Key Laboratory of Crystal Materials Shandong UniversityJinan250100China School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710054China

The appropriate regulation of band structure is an effective strategy in constructing efficient photocatalytic *** photocatalytic system mainly employs powder photocatalysts,which makes their recovery reliant on expensive separation processes and severely limits their industrial ***,we constructed a novel CdS/Ni_(3)S_(2)heterostructure using free-standing and flexible nickel fiber paper as the *** regulated energy band structure achieves effective electron–hole *** as-synthesized flexible photocatalyst exhibits considerable photocatalytic activity toward the H_(2)evolution reaction under visible-light irradiation,with an H_(2)production rate of5.63μmol·cm^(-2)·h^(-1)(14.1 mmol·g^(-1)cat·h^(-1)according to the catalyst loading content).Additionally,the otherwisewasted excited holes simultaneously drive organic transformations to yield value-added organic products,thus markedly improving the photocatalytic H_(2)evolution *** a photocatalytic system is scaled up further,where a self-supported 20 cm×25 cm sample achieves a champion H_(2)production rate of 60-80μmol·h^(-1)under practical sun *** newly developed self-supported photocatalyst produces opportunities for practical solar H2production with biomass upgrading.

关键词： Self-supporting photocatalyst CdS/Ni_(3)S_(2) heterojunction Hydrogen evolution Biomass upgrading Large-scaleapplication

桥墩承台大体积混凝土温度场监测与有限元分析

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铁道建筑 2024年第9期64卷 86-91页

作者：曹青中铁建设集团有限公司北京100040 北京工业大学工程抗震与结构诊治北京市重点实验室北京100124

为控制大体积混凝土浇筑后里表温差过大及温度裂缝的不利影响,通过对无冷却水管试验墩和有冷却水管承台的大体积混凝土温度场进行监测,研究在有无冷却水管降温措施下大体积混凝土内部温度场的分布及变化规律,并建立有限元模型分析有限... 详细信息

为控制大体积混凝土浇筑后里表温差过大及温度裂缝的不利影响,通过对无冷却水管试验墩和有冷却水管承台的大体积混凝土温度场进行监测,研究在有无冷却水管降温措施下大体积混凝土内部温度场的分布及变化规律,并建立有限元模型分析有限元模拟结果与实测数据之间的差异。结果表明:大体积混凝土浇筑后,混凝土升温速率大于降温速率;布设冷却水管降温措施可以明显降低大体积混凝土中心温度;升降温阶段,混凝土内部和表面温度升降温速率基本相同,且从内到外温度变化呈递减趋势,但无线性关系;有限元模拟结果与实测数据吻合较好。

关键词：大体积混凝土桥墩承台现场监测水化热分析温度场降温措施

金融科技赋能与实体经济修复——基于新冠疫情的冲击

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南开管理评论 2024年第6期27卷 16-26页

作者：王红建曹晴曹瑜强江西财经大学财经数据科学重点实验室江西财经大学金融学院广东外语外贸大学会计学院

探究我国实体企业在遭遇新冠疫情等不利冲击后如何稳定投资,对实体经济实现平稳发展意义重大。本文探究新冠疫情冲击背景下金融科技对实体企业投资的影响及内在机理。研究发现:金融科技显著提高了危机冲击下实体企业投资水平,该结论经... 详细信息

探究我国实体企业在遭遇新冠疫情等不利冲击后如何稳定投资,对实体经济实现平稳发展意义重大。本文探究新冠疫情冲击背景下金融科技对实体企业投资的影响及内在机理。研究发现:金融科技显著提高了危机冲击下实体企业投资水平,该结论经过系列稳健性检验后仍然成立。机制识别发现:金融科技能够显著降低抵押资产和会计信息在银行信贷中的作用,缓解实体企业在危机期间的资金约束,帮助实体企业抵抗危机的冲击。拓展性检验发现:金融科技对实体企业投资的促进作用对于成立时间更短及所在地区传统银行业欠发达的样本更加显著。经济后果检验发现:微观层面上,金融科技的发展能够增强危机冲击下的实体企业韧性,提高企业财务杠杆,但是对经营绩效的影响较为有限;宏观层面上,金融科技能显著降低危机发生后的宏观经济波动。本研究从实体企业投资视角揭示了金融科技影响实体经济运行规律的内在机理,在实践上为金融科技发展及经济复苏政策的制定提供了理论依据。

关键词：新冠疫情冲击金融科技经济修复实体企业投资

附加阻尼网的斜底式TLD减震控制理论与试验研究

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建筑结构学报 2024年第4期45卷 72-85页

作者：孙澔鼎何浩祥程扬曹青北京工业大学工程抗震与结构诊治北京市重点试验室北京100124 中铁建设集团有限公司北京100040

为解决传统调谐液体阻尼器(tuned liquid damper,TLD)中有效阻尼偏小、用水量偏大等问题,提出一种附加阻尼网的斜底式水箱调谐液体阻尼器(damping net and sloped-bottom tuned liquid damper,DNS-TLD),将水箱底面倾斜的TLD与阻尼网有... 详细信息

为解决传统调谐液体阻尼器(tuned liquid damper,TLD)中有效阻尼偏小、用水量偏大等问题,提出一种附加阻尼网的斜底式水箱调谐液体阻尼器(damping net and sloped-bottom tuned liquid damper,DNS-TLD),将水箱底面倾斜的TLD与阻尼网有机结合,强化水箱内液体晃动,可提供更大附加阻尼比并降低用水量。建立了附加DNS-TLD结构的力学模型,阐述其减震机制,提出了一种简便估算DNS-TLD总等效阻尼比的方法。通过单层钢框架振动台试验,对比分析了附加DNS-TLD及其他不同类型TLD的减震性能。将试验结果与数值模拟结果进行比较,进一步验证减震规律以及各类TLD总等效阻尼比估算方法的准确性。在此基础上,对附加DNS-TLD的10层钢筋混凝土框架结构进行地震作用下的动力时程分析,验证DNS-TLD对实际结构减震控制的有效性。振动台试验与数值模拟结果均表明,DNS-TLD有效结合了斜底式水箱TLD与阻尼网的优点,表现出更优的阻尼性能,相比于其他类型的TLD,其减震效率更高,鲁棒性和工程适用性更强。

关键词：调谐液体阻尼器斜底式水箱阻尼网调谐减震附加阻尼比

Plerixafor-based mobilization and mononuclear cell counts in graft increased the risk of engraftment syndrome after autologous hematopoietic stem cell transplantation

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Blood Science 2024年第3期6卷 48-54页

作者： Le-qing cao Qi Wen Bo-Ning Liu Zhen-Yu Zhao Xiao-Hui Zhang Lan-Ping Xu Huan Chen Yu Wang Lu Yu Feng-Rong Wang Xiao-Jun Huang Xiao-Dong Mo Peking University People’s Hospital Peking University Institute of HematologyNational Clinical Research Center for Hematologic DiseaseBeijing Key Laboratory of Hematopoietic Stem Cell TransplantationBeijingChina Hainan General Hospital Hainan Affiliated Hospital of Hainan Medical UniversityHaikouChina Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijingChina Research Unit of Key Technique for Diagnosis and Treatments of Hematologic Malignancies Chinese Academy of Medical SciencesBeijing 2019RU029China

Engraftment syndrome(ES)is one of the most common complications in the early phase after autologous hematopoietic stem cell transplantation(ASCT),and we aimed to evaluate the incidence and risk factors for ES patients receiving ASCT in the era of plerixafor-based mobilization.A total of 294 were enrolled,and 16.0%(n=47)experienced ES after *** main clinical manifestations were fever(100%),diarrhea(78.7%),skin rash(23.4%),and hypoxemia/pulmonary edema(12.8%).Plerixafor-based mobilization was associated with higher counts of CD3^(+)cells,CD4^(+)cells,and CD8^(+)cells in *** univariate analysis of the total cohort,age≥60 years,receiving ASCT at complete remission(CR),higher number of mononuclear cell(MNC),CD3^(+)cell counts,CD4^(+)cells as well as CD8^(+)cells transfused and plerixafor-based mobilization were associated with ES after *** analysis showed that age≥60 years(P=0.0014),receiving ASCT at CR(P=0.002),and higher number of MNC transfused(P=0.026)were associated with ES in total *** plasma cell disease subgroup,age≥60 years(P=0.013),plerixafor-based mobilization(P=0.036),and receiving ASCT at CR(P=0.002)were associated with *** with more risk factors had a higher risk of *** 1-year probabilities of relapse,non-relapse mortality,and survival were comparable between patients with and without ***,plerixafor-based mobilization may influence the composition of T lymphocytes in grafts and increase the risk of ES,particularly in patients with plasma cell disease.

关键词： Autologous stem cell transplantation Engraftment syndrome Plerixafor Risk factors

基于潜在数据挖掘的小样本数据库对抗攻击防御算法

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吉首大学学报（自然科学版） 2024年第1期45卷 30-35页

作者：曹卿闽南理工学院信息管理学院福建泉州362700

为了降低小样本数据库欺骗率,提升小样本数据库的攻击防御效果,设计了一种基于潜在数据挖掘的小样本数据库对抗攻击的防御算法(潜在数据挖掘的防御算法).采用改进的Apriori算法,通过频繁属性值集的工作过程获取准确的强关联规则优势,并... 详细信息

为了降低小样本数据库欺骗率,提升小样本数据库的攻击防御效果,设计了一种基于潜在数据挖掘的小样本数据库对抗攻击的防御算法(潜在数据挖掘的防御算法).采用改进的Apriori算法,通过频繁属性值集的工作过程获取准确的强关联规则优势,并从小样本数据库中挖掘潜在数据对抗攻击,同时优化候选集寻找频繁集的过程,然后利用关联分析检测对抗攻击,并通过可信度调度控制访问速率来防止产生恶意会话,实现小样本数据库对抗攻击防御.实验结果表明,潜在数据挖掘的防御算法可有效防御小样本数据库遭受的多种类型攻击,降低攻击产生的数据库欺骗率,保障小样本数据库服务器利用率的稳定性.

关键词：数据挖掘关联规则强关联规则小样本数据库攻击检测 Apriori算法