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Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： kai-kai Niu Chao-Qun Ma Rui-zhi Dong Hui liu Sheng-Sheng Yu Ling-Bao Xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

基于多时相Landsat影像的河流边滩提取研究

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现代测绘 2024年第2期47卷 12-16页

作者：姜雨宏谢相建刘开枝付瑞烨谭皓东华理工大学测绘与空间信息工程学院江西南昌330013 东华理工大学自然资源部环鄱阳湖区域矿山环境监测与治理重点实验室江西南昌330013

河流边滩是因河流沉积作用在岸边形成的沉积物,其变化可以间接反映出河流形态及其周围环境的演变。河流边滩的动态监测对于河流生态系统研究和航道管理有着非常重要的意义。针对河流边滩与部分建筑物影像光谱相似而难以区分的问题,基于L... 详细信息

河流边滩是因河流沉积作用在岸边形成的沉积物,其变化可以间接反映出河流形态及其周围环境的演变。河流边滩的动态监测对于河流生态系统研究和航道管理有着非常重要的意义。针对河流边滩与部分建筑物影像光谱相似而难以区分的问题,基于Landsat影像中边滩与河流的光谱、空间和物候等多维差异化特征,提出了一种新的河流边滩提取方法,综合利用多时相水体指数的二值变化检测方法和面向对象分析方法,成功提取了赣江中下游的河流边滩。一方面丰富了河流边滩监测的方法,为地理学研究提供新的观察视角;另一方面为赣江流域生态系统建设、环境治理和航运规划管理提供更丰富的河流边滩数据。

关键词：河流边滩面向对象影像分析变化检测差值分析赣江中下游 Landsat

Ultrafast pulse-dilation framing camera and its application for time-resolved X-ray diagnostic

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Nuclear Science and Techniques 2024年第7期35卷 101-114页

作者： Hou-zhi Cai Qiu-Yan Luo kai-Xuan Lin Xuan Deng Jun-kai liu kai-zhi Yang Dong Wang Jia-Jie Chen Jia-Heng Wang Jing-Hua Long Li-Hong Niu Yun-Fei Lei Jin-Yuan liu Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province Shenzhen Key Laboratory of Photonics and BiophotonicsCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China

An ultrafast framing camera with a pulse-dilation device,a microchannel plate(MCP)imager,and an electronic imaging system were *** camera achieved a temporal resolution of 10 ps by using a pulse-dilation device and gated MCP imager,and a spatial resolution of 100μm by using an electronic imaging system comprising combined magnetic *** spatial resolution characteristics of the camera were studied both theoretically and *** results showed that the camera with combined magnetic lenses reduced the field curvature and acquired a larger working area.A working area with a diameter of 53 mm was created by applying four magnetic lenses to the ***,the camera was used to detect the X-rays produced by the laser-targeting *** diagnostic results indicated that the width of the X-ray pulse was approximately 18 ps.

关键词： Inertial confinement fusion Plasma diagnostics Framing camera Combined lenses Pulse-dilation

Anti-inflammatory effect of extracts of Dendropanax dentige and Lycopodiastrum casuarinoides on rheumatoid arthritis and their underlying mechanism in rats

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中国药理学与毒理学杂志 2016年第10期30卷 1036-1037页

作者： CHEN Gang liu zhi-kai HAN Chen-yun LI Jia-shuang ZOU Yi-ping Key Laboratory of Natural Active Pharmaceutical Constituents of Jiangxi Province Yichun University

OBJECTIVE To investigate the anit-inflammatory effect of extracts of Dendropanax dentiger(Harms)Merr and Lycopodiastrum casuarinoides(Spring)Holub on rheumatoid arthritis(RA)using adjuvant arthritis(AA)rat model and possible *** The AA rat model of RA was induced in adult SparagueDawley(SD)rats by injecting of the adjuvant at base ***-week-old male SD rats were randomly divided into the following groups:normal saline group(blank control),*** decoction group(80g·kg-1·d-1),*** decoction group(80 g·kg·d-1),the total of glucoside Tripterygium(GTT)group(positive control,2 mg·kg-1·d-1).They were administered orally for *** of tissues arthritis rats was observed by H.E *** volume of paw swelling was measured and the arthritis inflammation index was *** expressions of tumor necrosis factor-α(TNF-α)and interlukin-1β(IL-1β)were detected by the ELISA *** addition,previous study has reported that plant-derived mi RNAs play a role for cross kingdom regulatory ***,we also performed RNA-seq technique to identify bioactive mi RNAs via comparative transcriptome analysis between *** and *** Comparing with AA model group,the volume of paw swelling and the arthritis index were increased significantly in the AA rat model group(P<0.01),suggesting that the AA model rats were prepared *** with the AA model group,the volume of paw swelling of *** decoction group,*** decoction group was decreased by 25.2%and 10.3%,respectively,and the arthritis index was decreased by 27.2%and 18.3%,*** with AA model group,TNF-αprotein expression of *** decoction group and *** decoction groups were decreased by 16.3%and 14.7%,and IL-1βprotein expression was decreased by 23.6%,18.9%(P<0.05,P<0.01),***,we found that some plant-derived homologous mi RNAs(such as mi RNA192 and mi RNA30a)associated with cell

关键词： rheumatoid arthrits aqueous extracts of D.dentiger and L.Cauarinoides anti-inflammatory effect miRNA cross-kingdom regulation

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： kai Yin Xiaopeng liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Quantum Neural Network for Quantum Neural Computing

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Research 2024年第1期2023卷 71-80页

作者： Min-Gang Zhou zhi-Ping liu Hua-Lei Yin Chen-Long Li Tong-kai Xu Zeng-Bing Chen National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China MatricTime Digital Technology Co.Ltd. Nanjing 211899China

Neural networks have achieved impressive breakthroughs in both industry and *** to effectively develop neural networks on quantum computing devices is a challenging open ***,we propose a new quantum neural network model for quantum neural computing using(classically controlled)single-qubit operations and measurements on real-world quantum systems with naturally occurring environment-induced decoherence,which greatly reduces the difficulties of physical *** model circumvents the problem that the state-space size grows exponentially with the number of neurons,thereby greatly reducing memory requirements and allowing for fast optimization with traditional optimization *** benchmark our model for handwritten digit recognition and other nonlinear classification *** results show that our model has an amazing nonlinear classification ability and robustness to ***,our model allows quantum computing to be applied in a wider context and inspires the earlier development of a quantum neural computer than standard quantum computers.

关键词： quantum thereby breakthrough

How to Construct a Lower Risk FOF Based on Correlation Network? The Method of Principal Component Risk Parity Asset Allocation

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Journal of Systems Science & Complexity 2024年第3期37卷 1052-1079页

作者： BAI Wei ZHANG Junting liu Haifei liu kai School of Management and Engineering Nanjing UniversityNanjing 210093China Postdoctoral Workstation of Bank of Jiangsu Co. LtdNanjing 210006China College of Finance Nanjing Agricultural UniversityNanjing 210095China University of Prince Edward Island 550 University AveCharlottetownPE C1A4P3Canada

In order to build a low-risk Fund of Funds(FOF), from the perspective of correlation, the principal component factor is used to improve the traditional risk parity model. Principal component analysis is used to decompose the underlying assets and generate unrelated principal component factors,and then the authors can construct a principal component risk parity portfolio. The proposed empirical results based on China’s mutual fund market show that the performance of principal component risk parity portfolio(PCRPP) is better than that of equal weight portfolio(EWP) and traditional risk parity portfolio(RPP). That is to say, not only the PCRPP in this paper has much lower risk than EWP and RPP, but also slightly better than EWP and RPP in terms of average return. Moreover, the study of dividing the underlying assets shows that the PCRPP in this paper is not sensitive to the underlying assets. The PCRPP in this paper is better than EWP and RPP for both the better performing funds and the worse performing funds. In addition, the empirical results on dynamic portfolio adjustments show that it is not appropriate to adjust asset allocation too frequently when the expected rate of return is calculated using the arithmetic mean.

关键词： Fund of funds(FOF) mutual funds portfolio risk principal component analysis risk parity portfolio

Lanthanide-based microlasers:Synthesis,structures,and biomedical applications

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Nano Research 2024年第1期17卷 97-111页

作者： Qian Zhang Yawei liu kai liu Hongjie Zhang Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Xiangfu Laboratory Jiaxing 314102China

The large size of lasers limits their applications in confined spaces,such as in biosensing and in vivo brain tissue *** this regard,micron-sized lasers have been *** exhibit great potential for biological detecting,remote sensing,and depth tracking due to their small sizes,sensitive properties of their spectral fingerprints,and flexible positional modulation in the ***-based luminescent materials that possess long excited-state lifetime,narrow emission bandwidth,and upconversion behaviors are promising as gain mediums for novel *** addition,lanthanide-based microlasers could be generated under natural ambient conditions with pumped or continuous light sources,which significantly promotes the practical applications of *** progress in the design,synthesis,and biomedical applications of lanthanide-based microlasers has been outlined in this *** ions doped and upconverted lanthanide-based microlasers are highlighted,which exhibit advantageous structures,miniaturized dimensions,and high lasing *** applications of lanthanide-based microlasers are further discussed,the upconverted microlasers show great advantages for biological applications owing to their tunable excitation and emission characteristics and excellent environmental ***,perspectives and challenges in the field of lanthanide-based microlasers are presented.

关键词： microlasers lanthanide-based luminescent materials upconversion nanoparticles biological applications

Study on macro and micro shear strength of continuously graded and gap-graded sand

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Particuology 2024年第3期86卷 101-116页

作者： Peiran Zhao Songyu liu kai Wu School of Transportation Southeast UniversityNanjing210096China

The particle gradation of sand has a significant influence on its shear strength,yet the similarities and differences between the effects of continuous and gap grading have yet to be fully *** this study,the discrete element method(DEM)was used to simulate biaxial tests on granular samples that were both continuously graded and *** macroscopic analysis revealed that the shear strength of continuously graded sands increases initially and then decreases as the uniformity of particle size distribution *** the other hand,the lack of medium particles in gap-graded sands amplifies the difference in particle size between coarse and fine particles,leading to a decrease in shear ***,both continuous and gap gradings affect the internal packing structure of the particle assembly,which consequently affects particle stress distributions,contact forces,coordination numbers,stress-induced anisotropies,and contact force networks,thus having an impact on the macroscopic shear *** global uniformity of particle size distribution was unidirectionally affected by continuous grading,while gap grading had a locally bidirectional *** findings provide a better understanding of the effects of particle grading on the macroscopic shear strength of sands.

关键词： Biaxial test Shear strength Particle gradation Discrete element method Micromechanics