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Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures

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Chinese Chemical Letters 2024年第3期35卷 316-320页

作者： wei Yuan Gui-Zhi Dong Hui Ning xiang-xiang Guan Jia-Feng Cheng Zi-wei Shi Xiu-Ji Du Si-Wen Meng Dong-Sheng liu Yuan-Chen Dong CAS Key Laboratory of Colloid Interface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dandong Bettersize Instruments Ltd. Dandong 118000China Key Laboratory of Organic Optoelectronics&Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Department of Chemistry Renmin University of ChinaBeijing 100872China

Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional *** this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA *** the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be *** advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature *** results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures.

关键词： Dynamic light scattering Self-assembly process DNA nanostructures Temperature transition ranges Rapid preparation

Atomically dispersed calcium as solid strong base catalyst with high activity and stability

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Green Energy & Environment 2024年第10期9卷 1619-1626页

作者： xiang-Bin Shao Zhi-wei Xing Si-Yu liu Ke-Xin Miao Shi-Chao Qi Song-Song Peng Xiao-Qin liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu Road

Solid strong base catalysts are highly attractive for diverse reactions owing to their advantages of neglectable corrosion,facile separation,and environmental ***,their widespread applications are impeded by basic components aggregation and low *** this work,we fabricate single calcium atoms on graphene （denoted as Ca1/G） by use of a redox strategy for the first time,producing solid strong base catalyst with high activity and *** precursor Ca（NO3）2is first reduced to CaO at 400℃ by the support graphene,forming CaO/G with conventional basic sites,and the subsequent reduction at 850℃ results in the generation of Ca1/G with atomically dispersed *** characterizations reveal that Ca single atoms are anchored on graphene in tetra-coordination （Ca–C2–N2） where N is in situ doped from Ca（NO3）*** atomically dispersed Ca,along with their anchoring on the support,endow Ca1/G with high activity and stability toward the transesterification reaction of ethylene carbonate with *** turnover frequency value reaches 128.0 h-1on Ca1/G,which is much higher than the traditional counterpart CaO/G and various reported solid strong bases (2.9–46.2 h-1).Moreover,the activity of Ca1/G is well maintained during 5 cycles,while 60% of activity is lost for the conventional analogue CaO/G due to the leaching of Ca.

关键词： Solid strong base Single Ca atoms Heterogeneous catalysts Transesterification Reaction

Flexible electrochemical capacitor based NiMoSSe electrode material with superior cycling and structural stability

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Chinese Chemical Letters 2024年第7期35卷 456-460页

作者： Jingxuan liu Shiqi Zhao xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

Constructing composited electrode material is considered to be an efficient strategy to improve their electrochemical *** can accelerate the charge transfer speed of ions and enhance the conductivity of ***,the formation of the hybrid structure can largely avoid the aggregation of two dimensional materials and increase the electrochemical active area of the *** this work,we synthesize NiMoSSe electrode materials on nickel foam by a facile hydrothermal *** prepared composite shows a specific capacitance of 1035 C/g at 1 A/g due to the synergistic effect between MoS_(2) and MoSe_(2) *** addition,the devices are assembled with NiMoSSe samples,which offers an energy density of 82.71 Wh/kg at a power density of 2700 W/kg.

关键词： Supercapacitors NiMoSSe Energy density Power density Cycling life

The SLEGS beamline of SSRF

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Nuclear Science and Techniques 2024年第7期35卷 20-30页

作者： Long-xiang liu Hong-wei Wang Gong-Tao Fan Hang-Hua Xu Yue Zhang Zi-Rui Hao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China

The Shanghai Laser Electron Gamma Source(SLEGS, located in BL03SSID) beamline at the Shanghai Synchrotron Radiation Facility(SSRF) is a Laser Compton Scattering(LCS) gamma source used for the investigation of nuclear structure, which is in extensive demand in fields such as nuclear astrophysics, nuclear cluster structure, polarization physics, and nuclear energy. The beamline is based on the inverse Compton scattering of 10640 nm photons on 3.5 GeV electrons and a gamma source with variable energy by changing the scattering angle from 20° to 160°. γ rays of 0.25-21.1 MeV can be extracted by the scheme consisting of the interaction chamber, coarse collimator, fine collimator, and attenuator. The maximum photon flux for 180° is approximately 10~7 photons/s at the target at 21.7 MeV, with a 3-mm-diameter beam. The beamline was equipped with four types of spectrometers for experiments in( γ,γ'),( γ,n),( γ,p), and( γ,α). At present, Nuclear Resonance Fluorescence(NRF) spectrometry, Flat-Efficiency neutron Detector(FED) spectrometry, neutron Time-Of-Flight(TOF) spectrometry, and Light-Charged Particle(LCP) spectrometry methods have been developed.

关键词： Shanghai Synchrotron Radiation Facility SLEGS Nuclear astrophysics Nuclear structure

High-sensitivity formaldehyde gas sensor based on Ce-doped urchin-like SnO_(2) nanowires derived from calcination of Sn-MOFs

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Frontiers of Materials Science 2024年第1期18卷 29-43页

作者： wei Xiao wei Yang Shantang liu Hubei Key Lab of Novel Reactor&Green Chemical Technology School of Chemistry and Environmental EngineeringWuhan Institute of TechnologyWuhan 430073China Hubei Key Laboratory of Wudang Local Chinese Medicine Research Department of ChemistrySchool of Pharmaceutical SciencesHubei University of MedicineShiyan 442000China

Metal-organic frameworks(MOFs)have attracted widespread attention due to their regular structures,multiple material centers,and various *** are always considered as one kind of ideal templates for developing highly sensitive and selective gas *** this study,the advantages of MOFs with the high specific surface area(71.9891 m^(2)·g^(-1))and uniform morphology were fully utilized,and urchin-like SnO_(2) nanowires were obtained by the hydrothermal method followed by the calcination using Sn-MOFs consisting of the ligand of C_(9)H_(6)O_(6)(H_(3)BTC)and Sn/Ce center ions as sacrificial *** unique urchin-like nanowire structure facilitated gas diffusion and adsorption,resulting in superior gas sensitivity.A series of Ce-doped SnO_(2) nanowires with different doping ratios were synthesized,and their gas sensing properties towards formaldehyde were *** resulted Ce-SnO_(2) was revealed to have high sensitivity(201.2 at 250℃),rapid response(4 s),long-term stability,and good repeatability for formaldehyde sensing,and the gas sensing mechanism of Ce-SnO_(2) exposed to formaldehyde was also systematically discussed.

关键词： Ce-SnO_(2) SnO_(2) gas sensor formaldehyde Sn-MOF

Global Stability to Steady Supersonic Rayleigh Flows in One-Dimensional Duct

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 279-296页

作者： Fenglun wei Jianli liu Department of Mathematics Shanghai University Newtouch Center for Mathematics of Shanghai University

Heat exchange plays an important role in hydrodynamical systems,which is an interesting topic in theory and *** this paper,the authors consider the global stability of steady supersonic Rayleigh flows for the one-dimensional compressible Euler equations with heat exchange,under the small perturbations of initial and boundary conditions in a finite rectilinear duct.

关键词： Compressible Euler equations Heat exchange Supersonic Rayleigh fow Steady solution Classical solution

Nest decoration:Black feathers prevent Crested Mynas from nest usurpation

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Avian Research 2024年第2期15卷 292-297页

作者： Jinmei liu wei Liang Ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou571158China

Nests are important structures for birds to raise their offspring and for *** birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of *** in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the *** this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box *** results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other *** black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage.

关键词： Extended phenotype Feathers Nest decoration Nest usurpation

Synthesis of core-shell nanostructured SiO_(2)/TiO_(2)photocatalysts via atomic layer deposition in a fluidized bed with central tube

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Particuology 2024年第8期91卷 19-28页

作者： wei liu Daoyin liu Zuyang Zhang Zhenkun Sun Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy&EnvironmentSoutheast UniversityNanjing 210096China

Fluidized bed atomic layer deposition is an efficient technique for particle coating with precise control over the film thickness and uniformity at the *** this study,a fluidized bed with a central tube is designed,where the central tube has two roles:improve fluidization and deliver precursors *** synthesis of core-shell structured SiO_(2)/TiO_(2)nanoparticle catalysts for photodegradation of tetracycline hydrochloride(TC)is carried out using TiCl_(4)and H_(2)O as precursors at 180℃under atmospheric *** the combination of vibration and central tube,the segregation of agglomerate size along the bed height is weakened,and the prepared SiO_(2)/TiO_(2)nanoparticles show excellent photocatalytic degradation performance:the degradation efficiency on TC is 96%under 300 W xenon lamp irradiation for 60 *** mechanism of enhanced photocatalytic activity is due to the Ti-O-Si bonds generated at the interface,which increase the ability to absorb sunlight and accelerate the separation of holes and electrons.

关键词： SiO_(2)/TiO_(2)nanoparticles Fluidization Atomic layer deposition Photocatalysts Photocatalytic mechanism

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