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Influence of composition and size on the thermodynamic stability and structural evolution of CuAlNi nanoclusters

中国化学会第30届学术年会-第十五分会：表界面结构调控与催化

作者： Jun Fang Yang Yang Jianping Xie Ning Yan State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech University Department of Chemical and Biomolecular Engineering National University of Singapore

Thiolate-protected Au nanoclusters(or thiolated Au NCs) are very promising catalysts due to their well-defined cluster size(atomic precision) and structure(atomically resolved).So thiolated Au NCs provide an ideal platform to reveal certain fundamental issues related to Au-based catalytic *** this study,6-mercaptohexanoic(MHA) protected Au25(MHA)18 nanoclusters(or thiolated Au NCs) deposited on various inorganic supports,including hydroxyapatite(HAP),TiO(Degussa P25),activated carbon(AC),pyrolyzed graphene oxide(PGO),and fumed SiO were prepared via a conventional impregnation *** that,calcination under a N2 stream was conducted to produce surface ligand-free,highly dispersed Au NCs *** effects of supports on the size and catalytic activity of Au NCs were systematically *** the size effect and metal–support interaction are crucial for the design of supported Au NCs as efficient catalysts for targeted reactions.

关键词： Au25 nanoclusters heterogeneous catalysis size effect support effect

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Progress in Natural Science:Materials International 2020年第4期30卷 477-484页

作者： Qing Liu Ye Su Keke Song Xiaoxu Wang Panpan Gao Chutian Wang Yuqin Xiao Xiaodong Jian Ping Qian Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interfere Science School of Mathematics and Physics University of Science and Technology Beijing National Supercomputer Center in Tianjin

The heating process for CuAlNi nanoclusters with cuboctahedral structure was studied by molecular dynamics simulation with the embedded atom method. A diffusionless martensitic transformation from the cuboctahedral(CO) to the icosahedral(ICO) structure before the melting point was found in some CuAlNi nanoclusters. The effects of element composition and cluster size on the thermodynamic stability and structural transformation of trimetallic nanoclusters were investigated. The results show that the CO–ICO transformation temperature was size-dependent and occurred only for small clusters. It was also observed that the CO–ICO transformation temperature firstly dropped and then raised as Al concentration increased, which may be strongly related to the release of excess energy. Furthermore, the surface segregation phenomenon was also observed that the lower surface energy components, such as Al and Cu atoms, segregated to the surface of CuAlNi nanoclusters. The changes in the melting points of Cu Al Ni nanoclusters with different alloy compositions and cluster sizes were also studied. And furthermore, the physical basis of structural transition of CuAlNi nanoclusters was discussed.

关键词： MD simulation Structural transformation Thermodynamic stability Alloy nanocluster size effect

size engineering of 2D MOF nanosheets for enhanced photodynamic antimicrobial therapy

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中国化学快报:英文版 2023年第9期34卷 219-224页

作者： Baoli Xue Xiwen Geng Haohao Cui Huiying Chen Zhikang Wu Hong Chen Hai Li Zhan Zhou Meiting Zhao Chaoliang Tan Jingguo Li Henan Provincial People’s Hospital People’s Hospital of Zhengzhou UniversityZhengzhou 450003China College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934China Luoyang Key Laboratory of Organic Functional Molecules College of Food and DrugLuoyang Normal UniversityLuoyang 471934China Institute of Advanced Materials(IAM)and Key Laboratory of Flexible Electronics(KLoFE) Nanjing Tech University(NanjingTech)Nanjing 211816China Department of Chemistry Institute of Molecular Aggregation ScienceTianjin Key Laboratory of Molecular Optoelectronic SciencesTianjin UniversityTianjin 300072China Department of Chemistry and Center of Super-Diamond and Advanced Films(COSDAF) City University of Hong KongHong Kong 999077China Shenzhen Research Institute City University of Hong KongShenzhen 518057China Pharmaceutical Sciences Laboratory Abo Akademi UniversityTurku 20520Finland

Although porphyrin-based metal-organic frameworks(MOFs)have been widely explored as photosensitizers for photodynamic therapy,how the size will affect the light-induced catalytic activity for generation of reactive oxygen species(ROS)still remain ***,we first report the size-controlled synthesis of two-dimensional(2D)porphyrin-based PCN-134 MOF nanosheets by a two-step solvothermal method to explore the size effect on its PDT performance,thus yielding enhanced photodynamic antimicrobial *** simply controlling the reaction temperature in the synthesis process,the bulk PCN-134 crystal,large PCN-134(L-PCN-134)nanosheets with a lateral size of 2–3μm and thickness of 33.2–37.5 nm and small PCN-134 nanosheets(S-PCN-134)with a lateral size of 160–180 nm and thickness of 9.1–9.7 nm were successfully ***,the S-PCN-134 nanosheets exhibit much higher photodynamic activity for ROS generation than that of the bulk 3D PCN-134 crystal and L-PCN-134 nanosheets under a660 nm laser irradiation,suggesting that the photodynamic activity of PCN-134 MOF increases when the size ***,the S-PCN-134 nanosheets show much enhanced performance when used as a photosensitizer for photodynamic antimicrobial activity and wound healing.

关键词： 2D nanosheets PCN-134 MOFs size effect Photodynamic therapy Antibacterial

Facile synthesis of size-tunable stable nanoparticles via click reaction for cancer drug delivery

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Science China Chemistry 2014年第4期57卷 633-644页

作者： CAO Ming LIU XiangRui TANG JianBin SUI MeiHua SHEN YouQing Key Laboratory of Biomass Chemical Engineering of Ministry of Education Center for Bionanoengineering of Zhejiang University Department of Chemical and Biological Engineering Zhejiang University

The stability and size of polymeric nanoparticles are two of the most important parameters determining their pharmacokinetics and tumor/drug accumulation efficiency in cancer-drug delivery. Herein, we report a facile one-pot synthesis of crosslinked nanoparticles(CNPs) with tunable sizes and polyethylene glycol(PEG) shells via click reactions. Simply by adjusting the contents of the macromonomer(PEG monoacrylate) in its reaction with ethylene diacrylate and a crosslinker containing hexa-thiols groups, the sizes of the resulting PEGylated crosslinked nanoparticles could be easily tuned from 10 to 90 nm. These nanoparticle cores could encapsulate hydrophobic drugs such as doxorubicin(DOX), and the unreacted thiol and acrylate groups could be used for drug conjugation or labeling. Thus, the nanoparticles provide a multifunctional platform for drug delivery. In vivo studies showed that the larger nanoparticles(about 83.7 nm) had a much longer blood-circulation time and better tumor-targeting efficiency. One of our most important findings was that the drug encapsulated in the crosslinked nanoparticles, even though little was released at pH 7.4 under in vitro conditions, had much faster blood clearance than the nanoparticles' carrier, suggesting that drug release in the bloodstream was significant.

关键词： crosslinked nanoparticles facile synthesis size effect pharmacokinetics tumor targeting

Impact of particle size and pH on protein corona formation of solid lipid nanoparticles:A proof-of-concept study

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Acta Pharmaceutica Sinica B 2021年第4期11卷 1030-1046页

作者： Wenhao Wang Zhengwei Huang Yanbei Li Wenhua Wang Jiayu Shi Fangqin Fu Ying Huang Xin Pan Chuanbin Wu School of Pharmaceutical Sciences Sun Yat-Sen UniversityGuangzhou 510006China College of Pharmacy Jinan UniversityGuangzhou 511443China

When nanoparticles were introduced into the biological media,the protein corona would be formed,which endowed the nanoparticles with new ***,controlling protein corona formation is critical to in vivo therapeutic *** the particle size is the most feasible method during design,and the infuence of media pH which varies with disease condition is quite *** impact of particle size and pH on bovine serum albumin(BSA)corona formation of solid lipid nanoparticles(SLNs)was studied *** BSA corona formation of SLNs with increasing particle size(120-480 nm)in pH 6.0 and 7.4 was *** techniques were employed for visualization study,conformational structure study and mechanism study,etc."BSA corona-caused aggregation"of SLN2-3 was revealed in pH 6.0 while the dispersed state of SLNs was maintained in pH 7.4,which signifcantly affected the secondary structure of BSA and cell uptake of *** main interaction was driven by van der Waals force plus hydrogen bonding in p H 7.4,while by electrostatic attraction in pH 6.0,and size-dependent adsorption was *** study provides a systematic insight to the understanding of protein corona formation of SLNs.

关键词： Protein corona Solid lipid nanoparticles BSA corona-Caused aggregation Nanoparticle-protein interaction size effect Cell uptake Medium pH Conformational structure

size-dependent vibrations and waves in piezoelectric nanostructures:a literature review

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International Journal of Smart and Nano Materials 2022年第3期13卷 391-431页

作者： Zinan Zhao Jun Zhu Weiqiu Chen Nantong Taisheng Blue Island Offshore Co. LtdQidongJiangsuChina Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province&Department of Engineering Mechanics&Soft Matter Research Center Zhejiang UniversityHangzhouZhejiangChina Key Laboratory of CAD&CG Zhejiang UniversityHangzhouZhejiangChina Shenzhen Research Institute of Zhejiang University ShenzhenGuangdongP.R.China

With the development and applications of nano-electro-mechanical systems,academic interest in the mechanical behavior of piezo-electric structures at nanoscale is *** unconven-tional phenomena have been observed either experimentally or through molecular dynamics *** most common and also important one is the size-dependent *** continuum mechanics with necessary modifications has been pro-ven to be very powerful in explaining these particular characteris-tics in a relatively simple theoretical *** article reviews the recent advances in understanding the size-dependent dynamic responses of piezoelectric nanostructures from the viewpoint of modified continuum *** attentions are paid to three advanced theories of piezoelectricity(*** piezoelec-tricity,surface piezoelectricity,and nonlocal piezoelectricity)and their abilities to predict unconventional vibration and wave char-acteristics in piezoelectric structures and devices at the *** article could serve as a useful reference for the future research on or design of nanostructures with multifield couplings.

关键词： size effect vibration wave piezoelectric structure continuum mechanics

Revealing the true origin of size-dependent Pd/C catalytic behavior towards formic acid decomposition

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Chinese Chemical Letters 2023年第1期34卷 457-460页

作者： Qinglei Meng Xian Wang Meiling Xiao Zhao Jin Junjie Ge Changpeng Liu Wei Xing Laboratory of Advanced Power Sources Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources Changchun 130022China State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Formic acid decomposition(FAD)is considered a promising hydrogen production route to facilitate the ambient storage and on demand release of hydrogen *** optimize the catalysts for FAD,efforts have been paid to explore the underlying reason for the varied catalytic activity among catalysts with similar composition but differed ***,such endeavors are highly challenging due to the deeply intermingled effects of electronic structure,particle size,and facets,***,to separately evaluate the respective effects of these factors,a series of catalysts with the same surface electronic structure and different particle size was prepared by cation dipole adjustment *** performance and characterization results showed that the catalysts with different sizes and facets exhibited similar intrinsic activity with deviation of less than 5%.However,they showed 252%deviation of site stability,indicating that only the optimized electronic structure could enhance the intrinsic activity and a smaller particle size could extend the catalyst’s life.

关键词： Hydrogen production Formic acid Catalyst deactivation size effect Facets effect

size-Dependent Geometrically Nonlinear Free Vibration of First-Order Shear Deformable Piezoelectric-Piezomagnetic Nanobeams Using the Nonlocal Theory

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Advances in Applied Mathematics and Mechanics 2018年第1期10卷 184-208页

作者： Raheb Gholami Reza Ansari Department of Mechanical Engineering Lahijan BranchIslamic Azad UniversityP.O.Box 1616LahijanIran Department of Mechanical Engineering University of GuilanP.O.Box 3756RashtIran

This article investigates the geometrically nonlinear free vibration of piezoelectric-piezomagnetic nanobeams subjected to magneto-electro-thermal loading taking into account size effect using the nonlocal elasticity *** this end,the sizedependent nonlinear governing equations of motion and corresponding boundary conditions are derived according to the nonlocal elasticity theory and the first-order shear deformation theory with von K´arm´an-type of kinematic *** effects of size-dependence,shear deformations,rotary inertia,piezoelectric-piezomagnetic coupling,thermal environment and geometrical nonlinearity are taken into *** generalized differential quadrature(GDQ)method in conjunction with the numerical Galerkin method,periodic time differential operators and pseudo arclength continuation method is utilized to compute the nonlinear frequency response of piezoelectric-piezomagnetic *** influences of various parameters such as non-dimensional nonlocal parameter,temperature change,initial applied electric voltage,initial applied magnetic potential,length-to-thickness ratio and different boundary conditions on the geometrically nonlinear free vibration characteristics of piezoelectric-piezomagnetic nanobeams are demonstrated by numerical *** is illustrated that the hardening spring effect increases with increasing the non-dimensional nonlocal parameter,positive initial applied voltage,negative initial applied magnetic potential,temperature rise and decreases with increasing the negative initial applied voltage,positive initial applied magnetic potential and length-tothickness ratio.

关键词： Piezoelectric-piezomagnetic nanobeams geometrically nonlinear free vibration nonlocal elasticity theory size effect magneto-electro-thermal loading

size-dependent behaviors of viscoelastic axially functionally graded Timoshenko micro-beam considering Poisson effects

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Journal of Southeast University(English Edition) 2020年第2期36卷 170-180页

作者： Zhou Bo Zheng Xueyao Kang Zetian Xue Shifeng College of Pipeline and Civil Engineering China University of Petroleum (East China) Qingdao 266580 China

A size-dependent continuum-based model is developed for the functionally graded(FG)Timoshenko micro-beams with viscoelastic properties,in which material parameters vary according to the power law along its axial *** size effect is incorporated by employing the modified couple stress theory and Kelvin-Voigt viscoelastic model,so that viscous components are included in the stress and the deviatoric segments of the symmetric couple stress *** components of strain,curvature,stress and couple stress are formulated by combining them with the Timoshenko beam *** on the Hamilton principle,the governing differential equations and boundary conditions for the micro-beam are expressed with arbitrary beam section shape and arbitrary type of *** size effect,FG effect,Poisson effect,and the influence of the beam section shape on the mechanical behaviors of viscoelastic FG micro-beams are investigated by taking the simply supported micro-beam subjected to point load as an *** show that the size effect on deflection,normal stress and couple stress are obvious when the size of the micro-beam is small enough,and the FG effects are obvious when the size of the micro-beam is large ***,the Poisson ratio influences the size effect significantly and the beam section shape is also an important factor influencing the mechanical behavior of the micro-beam.

关键词： viscoelastic functionally graded micro-beam size-dependent behaviors size effect functionally graded effect Poisson effect space