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Journal of Rare Earths 2010年第6期28卷 847-853页

作者： S. P. Sinha Alfredo M. Simas Gustavo L. C. Moura Scientific Research & Development Departamento de quimica fundamental CCEN Universidade Federal de Pernambuco

Theoretical investigation on the structures of the octacoordinated [Nd(CO3)4]5-and the nonacoordinated [Nd(CO3)***2]5-complexes, using the SPARKLE parameters of the lanthanides within MOPAC, revealed that they possessed dodecahedral and square antiprismatic structures respectively with an average Nd-O distance of 0.249 nm. These structures and the Nd-O distances agreed well with those experimentally found in the crystal structures. Replacing the water molecule with a fluoride ion or a mondentatecarbonato ligand resulted in a nonacoordinated distorted square antiprismatic structures where the trans-carbonato groups were twisted. The corresponding decacoordinated structures with two fluoride ions or a bidentatecarbonato group, [Nd(CO3)4·F2]7-and [Nd(CO3)5]7-, were also investigated. In both cases considerable twisting of the transcarbonato groups was observed.

关键词： lanthanides theoretical molecular models octacoordination carbonato complexes adducts MOPAC SPARKLE rare earths

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： Douglas L.Bernardo Cristiano C.Bastos Antonio C.Pavao Departamento de quimica fundamental Universidade Federal de PernambucoRecife50740-540Brazil Departamento de quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,N,and ∑ orbital and radial *** four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)*** first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)*** orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)*** N orbital excitations are identified with the N(1520),N(1680),N(2190),N(2220),and N(2600)*** first four radial excitations of the N family correspond to the N(1440),N(1880),N(2100),and N(2300)*** orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)*** proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Comparison between the theoretical models and experimental structures of some oc tacoordinated Ln(Ⅲ)-bis-dipyridyl-bis-dichloroacetato-diaquo complexes and their phenanthroline analogues

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Journal of Rare Earths 2010年第S1期28卷 83-85页

作者： S. P. SINHA Alfredo M. SIMAS Gustavo L. C. MOURA SRD 6565 Willowick Pl.DaytonOHIO 45459-3005U.S.A. Departamento de quimica fundamental CCENUniversidade Federal de Pernambuco50590-470Recif ePEBrazil

The title complexes were modeled using the semiempirical MOPAC and the newly developed SPARKLE paramerters of the lanthanides. The calculated bond dis tances and angles agreed well with those found from crystal structure measuremen ts. This technique allows us to screen a large number of molecules and get struc tural information within a very short time.

关键词： lanthanide complex theoretical models octacoordination dipyridyl p henanthroline MOPAC SPARKLE rare earths

Recent progress in flexible Zn-ion hybrid supercapacitors: fundamentals, fabrication designs, and applications

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Carbon Energy 2023年第1期5卷 82-122页

作者： Muhammad Sufyan Javed Sumreen Asim Tayyaba Najam Muhammad Khalid Iftikhar Hussain Awais Ahmad Mohammed A.Assiri Weihua Han School of Physical Science and Technology Lanzhou UniversityLanzhouGansuChina Institute of Chemistry Khwaja Fareed University of Engineering and Information TechnologyPunjabPakistan College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhenGuangdongChina Department of Mechanical Engineering City University of Hong KongKowloonHong KongChina Departamento de quimica Organica Universidad de CordobaCordobaSpain Department of Chemistry Faculty of ScienceKing Khalid UniversityAbhaSaudi Arabia

One of the most exciting new developments in energy storage technology is flexible Zn-ion hybrid supercapacitors(f-ZIHSCs),which combine the high energy of Zn-ion batteries with high-power supercapacitors to satisfy the needs of portable flexible ***,the development of f-ZHSCs is still in its infancy,and there are numerous barriers to overcome before they can be widely implemented for practical *** review gives an up-to-date description of recent achievements and underlying concepts in energy storage mechanisms of f-ZIHSCs and emphasizes the critical role of cathode,anode,and electrolyte materials systems in speeding the prosperity of *** innovative nanostructured-based cathode materials for f-ZIHSCs include carbon(e.g.,porous carbon,heteroatom-doped carbon,biomass-derived porous carbon,graphene,etc.),metal-oxides,MXenes,and metal/covalentorganic frameworks,and other materials(e.g.,activated carbon,phosphorene,etc.)are mainly ***,the latest developments in flexible anode and electrolyte frameworks and impacts of electrolyte compositions on the electrochemical properties of f-ZIHSC are ***,the advancements based on fabrication designs,including quasi-solid-state,micro,fiber-shaped,and all climate-changed f-ZIHSCs,are discussed in ***,a summary of current challenges and recommendations for the future progress of advanced f-ZIHSC are *** review article is anticipated to further understand the viable strategies and achievable approaches for assembling high-performance f-ZIHSCs and boost the technical revolutions on cathode,anode,and electrolytes for f-ZIHSC devices.

关键词： electrode electrolyte flexible MOFs MXenes Zn-ion hybrid supercapacitor

3D Printed Gelatin Scaffold with Improved Shape Fidelity and Cytocompatibility by Using Antheraea pernyi Silk Fibroin Nanofibers

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Advanced Fiber Materials 2022年第4期4卷 758-773页

作者： Shengzhi Zou Suna Fan Ana L.Oliveira Xiang Yao Yaopeng Zhang Huili Shao State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Shanghai Engineering Research Center of Nano‑Biomaterials and Regenerative MedicineCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620People’s Republic of China CBQF‑Centro de Biotecnologia e quimica Fina‑Laboratorio Associado Escola Superior de BiotecnologiaUniversidade Catolica PortuguesaRua Diogo Botelho 13274169‑005 PortoPortugal

Gelatin(G)is a commonly used natural biomaterial owing to its good biocompatibility and easy ***,using pure gelatin as a bioink can barely achieve an ideal shape fidelity in 3D *** this study,Antheraea pernyi silk fibroin nanofibers(ASFNFs)with arginine-glycine-aspartic acid(RGD)peptide and partial natural silk structure are extracted and combined with pure gelatin bioink to simultaneously improve the shape fidelity and cytocompatibility of corresponding 3D printed *** show that the optimum printing temperature is 30℃ for these *** printed filaments using 16G/4ASFNFs bioink(16wt%gelatin and 4wt%ASFNFs)demonstrate better morphology and larger pore size than those printed by pure gelatin bioink(20G,20wt%gelatin),thus successfully improve the shape fidelity and porosity of the 3D printed *** 16G/4ASFNFs scaffold also demonstrate higher swelling ratio and faster degradation rate than the pure gelatin ***,the cell viability and proliferation ability of Schwann cells cultured on the 16G/4ASFNFs scaffold are significantly superior than those cultured on the pure 20G *** ASFNFs enhanced 16G/4ASFNFs scaffold reported here are expected to be a candidate with excellent potential for biomedical applications.

关键词： Antheraea pernyi silk fibroin nanofiber 3D printed scaffold Shape fidelity Cytocompatibility Gelatin

How minor structural changes generate major consequences in photophysical properties of RE coordination compounds;resonance effect,LMCT state

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Journal of Rare Earths 2020年第5期38卷 552-563页

作者： Ewa Kasprzycka Albano N.Carneiro Neto Viktor A.Trush Lucjan Jerzykiewicz Vladimir M.Amirkhanov Oscar L.Malta Janina Legendziewicz Paula Gawryszewska University of Applied Sciences-Fachhochschule Münster Department of ChemicalEngineeringStegerwaldstr.39Steinjurt48565Germany Physics Department and CICECO-Aveiro Institute of Materials University of Aveiro38 JO-193AveiroPortugal Department o f Chemistry Taras Shevchenko National University of Kyivul.Volodymyrska 64Kyiv01601 Ukraine Faculty of Chemistry University of Wroclaw14 F.Joliot-Curie Street50-383WroclawPoland Departamento de quimica fundamental Universidade Federal de Pernambuco Cidade Universitaria RecifePE50740-560Brazil

Lanthanide coordination compounds of the formula Na[Ln(L)4](1 Ln),where Ln=La^3+,Eu^3+,Gd^3+,Tb^3+,L=[L]-and HL=dimethyl(4-methylphenylsulfo nyl)amidophosphate,were *** structural and spectro scopic properties were discussed in detail based on X-ray diffraction measurements,IR spectroscopy,absorption and emission spectroscopy at 293 and 77 K and theoretical calculations of the intramolecular energy transfer(IET)*** calculations were used to investigate the 1 Ln electronic properties re quired to calculate the transition rates.30 and 22 pathways of intramolecular nonradiative energy transfer were examined in the case of 1 Eu and 1 Tb,*** is shown that the main pathway for sensitization of the lanthanide emission is either the triplet(1 Eu)or singlet(1 Tb)transfer,occurring mainly through the exchange *** energy rates for energy transfer from S1 and T1 equal WS=1.53×10^5 s^-1(1 Eu),WT=5.14×10^6 s^-1(1 Eu)and WS=4.09×10^7 s^-1(1 Tb),WT=6.88×10^5 s^-1(1 Tb).The crucial role of the 7 F5 level in the energy transfer process of 1 Tb and the participation of the LMCT state in the depopulation of the ligand singlet state of 1 Eu were *** influence of the resonance effect on the splitting of the7 F1 level in 1 Eu was *** comparing the properties of 1 Ln with the properties of 2 Ln coordination compounds,sharing the same ligand and crystallizing in the same crystallographic system(monoclinic),but with a different space group,it is demonstrated how slight structural changes can affect the photophysical properties of Ln compounds.

关键词： Lanthanide Phosphorylated sulfonamides Energy transfer Antenna effect Crystal structure Resonance effect

在含小银粒的掺铕的氟硼酸盐玻璃中等离子体激光的谱带位移(英文)

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发光学报 1988年第1期 46-53页

作者： O.L.Malta,P.A.Santa-Cruz,G.F.deSá Departmento de quimica fundamental e Departmento de Fisica da UFPE Cidade Universnária-Recife-PE-50000-Brasil Departmento de quimica fundamental e Departmento de Fisica da UFPE Cidade Universnária-Recife-PE-50000-Brasil Departmento de quimica fundamental e Departmento de Fisica da UFPE Cidade Universnária-Recife-PE-50000-Brasil

我们提出并讨论了在含分散银粒的氟硼酸盐玻璃中等离子体激光的吸收峰位置随氧化铈浓度而在相当宽的光谱范围内变化的实验观测。

关键词：氟硼酸盐氟化合物等离子体银粒激光 Eu Ag 谱带

Molecular Modeling of the Octacoordinated Tetracarbonato-Nd(Ⅲ),[Nd(CO3)4]5-,Complex and its Nonacoordinated Fluoro and Aquo Adducts

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Molecular Modeling of the Octacoordinated Tetracarbonato-Nd(...

Engineering magnetic nanostructures with inverse hysteresis loops

第六届国际稀土开发与应用研讨会

作者： S.P.SINHA Alfredo M.SIMAS Gustavo L.C.MOURA SRD 6565 Willowick PI.DaytonOHIO 45459-3005U.S.A. Departamento de quimica fundamental CCENUniversidade Federal de Pernambuco50590-470RecifePEBrazil

Carbonato complexes of the lanthanides and the actinides play an important role in the environment. In seawater,lanthanides and actinides are known to complex with the carbonate ion(CO).Depending on the concentration of the carbonate ion,the pH and the ionic strength,various species,including[Ln(CO)] are present in aqueous ***[1]and others[2,3]have shown the quantitative formation of the tetracarbonato complex,[Ln(CO)],at a pH～12. Sinha[3]observed extreme hypersensitivity of the fluorescent D→F transition in tetracarbonato complex of Eu(Ⅲ).He was also able to show[1]the presence of a difluoro adduct of Eu(Ⅲ)-tetracarbonato complex from the fluorescent lifetime ***,Sinha was not able to isolate the lanthanide(Ⅲ)-tetracarbonato complexes or the difluoro adduct in the solid state. It was of interest to investigate the structures of the octacoordinated lanthanide-tetracarbonato(Ⅰ) complexes and the fluoro and aquo adducts using molecular modeling technique and the recently developed SPARKEL parameters for all lanthanide *** semiemperical[4]approach has great advantage in screening a large number of analogous structures hundred times faster than the ab-initio methods and generating good geometry, bond lengths and bond angles. The Ln-O bond lengths of the octacoordinated(Ⅰ) complexes are listed *** values agree very well with those obtained for the bidentate carbonato complexes of the lanthanides[5].The structure of the "four-bladed propeller-shaped" complex-(Ⅰ) may be approximated as a staggered square *** calculated structure of Nd-(Ⅰ) complex is shown in ***.2 and Fig.3 show the calculated structures for the mono-fluoro and monaquo adducts. The mono-fluoro adduct is shown to have a monocapped-square antiprismatic structure with an average Nd-O distance of 2.53A and a longer Nd-F distance(2.55A).There is a slight increase in the Nd-O bond length in nonacoordinated mono-fluoro adduct in comparison to the octacoord

关键词： Lanthanide Complex Theoretical Molecular Models Octacoordination Tetracarbonato Complex

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Nano Research 2016年第8期9卷 2347-2353页

作者： Beatriz Mora Nastassia Soriano Carolina Redondo Alberto Arteche David Navas Rafael Morales Dpto. de quimica-Fisica Universidad del Pais Vasco UPWEHU 48940 Leioa Spain IFIMUP-IN and Dept. Fisica e Astronomia Universidade do Porto 4169007 Porto Portugal Dpto. de Qulmica-Ffsica & BCMaterials Universidad del Pals Vasco UPV/EHU 48940 Leioa Spain IKERBASQUE Basque Foundation for Science 48011 Bilbao Spain

Top-down lithography techniques allow the fabrication of nanostructured elements with novel spin configurations, which provide a new route to engineer and manipulate the magnetic response of sensors and electronic devices and understand the role of fundamental interactions in materials science. In this study, shallow nanostructure-patterned thin films were designed to present inverse magnetization curves, i.e., an anomalous magnetic mechanism characterized by a negative coercivity and negative remanence. This procedure involved a method for manipulating the spin configuration that yielded a negative coercivity after the patterning of a single material layer. Patterned NiFe thin films with trench depths between 15%-25% of the total film thickness exhibited inverse hysteresis loops for a wide angular range of the applied field and the trench axis. A model based on two exchange-coupled subsystems accounts for the experimental results and thus predicts the conditions for the appearance of this magnetic behavior. The findings of the study not only advance our understanding of patterning effects and confined magnetic systems but also enable the local design and control of the magnetic response of thin materials with potential use in sensor engineering.

关键词： magnetic nanostructures magnetic patterning effects inverted loops negative coercivity negative remanence

Anomalous transport of light at the phase transition to localization:strong dependence with incident angle

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光子学研究：英文版 2018年第10期6卷 929-942页

作者： ERNESTO JIMENEZ-VILLAR M.C.S.XAVIER NIKLAUS U.WETTER VALDECI MESTRE WELITON S.MARTINS GABRIEL F.BASSO V.A.ERMAKOV F.C.MARQUES GILBERTO F.DE SA Instituto de Pesquisas Energeticas e Nucleares CNEN_IPENSao PauloSP 05508-000Brazil Departamento de Ffsica Universidade Federal da ParaibaJoao PessoaPB 58051-970Brazil Departamento de Fisica Universidade Estadual da ParaibaArarunaPB 58233-000Brazil CCEA Universidade Estadual da ParaibaPatosPB 58706-560Brazil Departamento de Fisica Universidade Federal Rural de PernambucoRecifePE 52171-900Brazil Departamento de Informatica Universidade Federal da ParaibaJoao PessoaPB 58055-000Brazil Departamento de Fisica Aplicada Universidade Estadual de CampinasCampinasSP 13083-859Brazil quimica fundamental Universidade Federal de PernambucoRecifePE 50670-901Brazil

There has been a growing interest in disordered optical media in recent years due to their potential applications in solar collectors, random lasers, light confinement, and other advanced photonic functions. This paper studies the transport of light for different incidence angles in a strongly disordered optical medium composed of core-shell TiO_2@Silica nanoparticles suspended in an ethanol solution. A decrease of optical conductance and an increase of absorption near the input border are reported when the incidence angle increases. The specular reflection, measured for the photons that enter the sample, is lower than the effective internal reflection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of *** study represents a novel approach in order to understand the complex physics involved at the phase transition to localization.

关键词：光学介质太阳能通讯技术发展现状