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Raman spectroscopy of isolated carbyne chains confined in carbon nanotubes:Progress and prospects

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Chinese Physics B 2022年第12期31卷 532-542页

作者： Johannes M.A.Lechner Pablo Hernández López Sebastian Heeg institut fur physik and IRIS Adlershof Humboldt Universitat zu Berlin12489 BerlinGermany

Carbyne is an infinitely long linear chain of carbon atoms with sp1hybridization and the truly one-dimensional allotrope of *** obtaining freestanding carbyne is still an open challenge,the study of confined carbyne,linear chains of carbon encapsulated in carbon nanotubes,provides a pathway to explore carbyne and its remarkable properties in a well-defined *** this review,we discuss the basics and recent advances in studying single confined carbyne chains by Raman spectroscopy,which is their primary spectroscopic characterization *** highlight where single carbyne chain studies are needed to advance our understanding of confined carbyne as a material system and provide an overview of the open questions that need to be addressed and of those aspects currently under debate.

关键词： carbyne linear carbon chains carbon nanotubes Raman spectroscopy

Growth-induced Stacking Faults of ZnO Nanorods Probed by Spatial Resolved Cathodoluminescence

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Chinese Physics Letters 2012年第7期29卷 261-264页

作者： XIE Yong JIE Wan-Qi WANG Tao WIEDENMANN Michael NEUSCHL Benjamin MADEL Manfred WANG Ya-Bin FENEBERG Martin THONKE Klaus State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072 institut fur Quantenmaterie/Gruppe Halbleiterphysik Universitat Ulm89069 UlmGermany institut fur experimentelle physik Otto-von-Guericke-Universitat Magdeburg39106 MagdeburgGermany

Low density ZnO nanorods are grown by modified chemical vapor deposition on silicon substrates using gold as a *** use high resolution photoiuminescence spectroscopy to gain the optical properties of these nanorods in large *** as-grown samples show sharp near-band-gap luminescence with a full width at half maximum of bound exciton peaks at about 300μeV,and the ratio of ultraviolet/yellow luminescence larger than *** spatial and spectral resolved scanning electron microscope-cathodoluminescence is performed to excite the ZnO nanorods in single rods or different positions of single rods with the vapour-solid grovth *** bottom of the nanorod has a 3.31-eV luminescence,which indicates that basal plane stacking faults are related to the defects that are created at the first stage of growth due to the misfit between ZnO and Si.

关键词： vapour Spatial ultraviolet

GEOCHEMICALLY CONTROLLED CALCITE PRECIPITATION BY CO_2-OUTGASSING: FIELD MEASUREMENTS OF PRECIPITATION RATES IN COMPARISON TO THEORETICAL PREDICTIONS

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中国岩溶 1992年第S1期11卷 9-24页

作者： W.Dreybrodt D.Buhmann J.Michaelis E.Usdowski University of Bremen lnstitut fur Experimentelle Physik 2800 Bremen GermanyUniversity of Bremenlnstitut fur Experimentelle Physik 2800 Bremen GermanyUniversity of Gottingen Sedimentpetrographisches Institut 3400 Gottingen GermanyUniversity of Gottingen Sedimentpetrographisches Institut 3400 Gottingen Germany

A small spring fed stream precipitates calcite by outgassing of CO2 due to chemically controlled inorganic processes. The chemical composition of the water was measured along 9 stations downstream with respect to Ca2+, Mg2+, Na+,K+, Cl-, carbonate alkalinlty, and SO42-. Temperature and pH were measured in situ. Small rectangular shaped tablets of limestone from the area were immersed into the stream for short periods and water analyses were carried out at the same time. From weight increase of the tablets, precipitation rates

关键词： carbonate limestone downstream chemically dissolution immersed tablets inorganic shaped strata

Nuclear Dynamics at the Particle Threshold

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原子核物理评论 2015年第2期32卷 129-136页

作者： Nadia Tsoneva Horst Lenske institut fur Theoretische physik Universitat Gieβen

Recently, new low-energy modes of excitation called pygmy resonances have been *** distinct feature is the close connection to nuclear skin oscillations. A successful description of the pygmy resonances could be achieved in a microscopic theoretical approach which incorporates the density functional theory and QRPA formalism extended with multi-phonon degrees of freedom. The latter is found of crucial importance for the understanding of the fine structure of nuclear electric and magnetic excitations at low energies. Corresponding microscopic multi-phonon response functions are implemented in the studies of s-process of nucleosynthesis.

关键词： microscopic nuclear model density functional theory extended quasiparticle-random-phase-approximation nucleon-capture reactions stellar nucleosynthesis

Statistics for Surface Modes of Nanoparticles with Shape Fluctuations

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Communications in Computational Physics 2010年第10期8卷 1224-1241页

作者： Felix Ruting Hannes Uecker institut fur physik Carl von Ossietzky UniversitatOldenburg D-26111Germany institut fur Mathematik Carl von Ossietzky UniversitatOldenburg D-26111Germany

We develop a numerical method for approximating the surface modes of sphere-like nanoparticles in the quasi-static limit,based on an expansion of(the angular part of)the potentials into spherical *** of the results obtained in this manner with exact solutions and with a perturbation ansatz prove that the scheme is accurate if the shape deviations from a sphere are not too *** method allows fast calculations for large numbers of particles,and thus to obtain statistics for nanoparticles with random shape *** an application we present some statistics for the distribution of resonances,polariziabilities,and dipole axes for particles with random perturbations.

关键词： Electrostatic(boundary-value problems) collective excitations(plasmons) shape fluctuations numerical scheme spherical harmonics projection method

Review on Recent Advances of Cathode Materials for Potassium-ion Batteries

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Energy & Environmental Materials 2020年第1期3卷 56-66页

作者： Mo Sha Long Liu Huaping Zhao Yong Lei Fachgebiet Angewandte Nanophysik Institut fur Physik&IMN MacroNano■(ZIK)Technische Universitat IlmenauIlmenauGermany

Potassium-ion batteries(PIBs) as a promising supplement to lithium-ion batteries have drawn great attention attributing to the abundant potassium resources, the fast-ionic conductivity of potassium ions in electrolyte, and the low standard redox potential of potassium. However, the development of PIBs is still in its infancy, which is largely restricted by the fact that the electrode materials, especially the cathode materials of PIBs, are far from satisfactory in practical applications regarding the capacity, voltage, and cycle life. Therefore, most of current research efforts have been devoted to exploring new and high-performance electrode materials for achieving PIBs with high capacity and voltage as well as excellent cyclability. In this review,the recent advancements on cathode materials for PIBs are specially summarized. Besides, technological developments, scientific challenges, and future research opportunities of cathode materials for PIBs are also briefly outlooked.

关键词： cathode materials electrochemical properties potassium-ion batteries recent development

Pressure and Spectral Density of Fermions at Finite Temperature

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Chinese Physics Letters 1999年第10期16卷 709-711页

作者： HOU De-fu U.Heinz LI Jia-rong institute of Particle Physics Huazhong Normal UniversityWuhan 430079 institut fur Theoretische physik Universitat RegensburgD-93040 RegensburgGermany

The pressure of a fermion system is expressed as a mass integral over the full two-point spectral densities within the real time formalism by use of the Keldysh representation for the *** simpliSes the calculation significantly and allows a Dyson *** expression is used to demonstrate that potential infrared divergences are rendered *** apply it to check the pressures of an ideal fermion gas and of a chemically non-equilibrated quantum chromodynamics plasma.

关键词： Fermi apply render

Light Scattering and SAXS Study of AOT Microemulsion at Low Size Droplet

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Soft Nanoscience Letters 2012年第1期2卷 8-12页

作者： Soheil Sharifi Masoud Amirkhani Jahanbakhsh Mashaiekhy Asla Mohamad Reza Mohammadi Othmar Marti Department of Physics University of Sistan and Baluchestan institut fur experimentelle physik Universitat Ulm

We study collective diffusion coefficient (Dc) of Water-in-oil nanoemulsions (L2 phase) stabilized by AOT and dispersed in n-Decane oils by dynamic light scattering (DLS). At constant water concentration we vary the oil concentration and there is clear evidence for a changing collective diffusion coefficient of the droplets in AOT nanoemuslion. The collective diffusion coefficient in AOT nanoemulsions is studied from relaxation investigations with dynamic light scattering. Also, we study the collective diffusion coefficient (Dc) of droplets with add the TBAC to the droplets of AOT nanoemulsion. We discuss the results with study structural investigations with small-angle x-ray scattering. The results of this study suggest that the formation of non-spherical aggregates at low concentration of droplets can describe the behavior of the collective diffusion coefficient at AOT nanoemulsion.

关键词： Nano-droplet Microemulsions Light scattering SAXS Diffusion

Light Scattering Study of Mixture of Polyethylene Glycol with C<sub>12</sub>E<sub>5</sub>Microemulsion

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Soft Nanoscience Letters 2011年第3期1卷 76-80页

作者： Soheil Sharifi Masoud Amirkhani Department of Physics University of Sistan and Baluchestan institut fur experimentelle physik Universitat Ulm

The mixture of C12E5 microemulsion with PEG have been studied by small-angle X-ray scattering and dynamic light scattering in order to determine structure and dynamic of the system. Light scattering experiment shown an exponential relaxation for pure C12E5 microemulsion that with increasing of PEG concentration in the C12E5 microemulsion, relaxation becomes non-exponential, which demonstrates that increase of cooperativity. The study structure of the system with SAXS experiment, shown with increasing of PEG concentration, the size of the droplet doesn’t change but interaction between droplets increases that have agreement with light scattering data’s.

关键词： Nano-droplet microemulsion PEG Light scattering SAXS