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101.
Liping Li Quan Wein Chuanbin Jiang Xiaolin Ren Zhigou Yao Wenhui Su 《Hyperfine Interactions》1995,96(1):237-243
The samples of Eu1–x
Sr
x
FeO3–y
(x=0.0–1.0) were prepared by the solid state reaction method. Their X-ray diffraction patterns and57Fe Mössbauer spectra at room temperature were measured. It is found that Sr ions incorporate in the lattice of EuFeO3, the change of crystal structure is related to the dopant.57Fe Mössbauer spectra consist of one magnetic, one doublet and one single paramagnetic components. The Fe ions in the cubic phase are in intermediate valence state between Fe(III) and Fe(IV) and may participate in electron hopping. 相似文献
102.
Microscopic phonon theory of semiconductor nanocrystals (NCs) is reviewed in this paper. Phonon modes of Si and Ge NCs with
various sizes of up to 7 nm are investigated by valence force field theory. Phonon modes in spherical SiGe alloy NCs approximately
3.6 nm (containing 1147 atoms) in size have been investigated as a function of the Si concentration. Phonon density-of-states,
quantum confinement effects, as well as Raman intensities are discussed.
相似文献
103.
Zhang Hengkai Zhang Yaokang Yang Guang Ren Zhiwei Yu Wei Shen Dong Lee Chun-Shing Zheng Zijian Li Gang 《中国科学:化学(英文版)》2019,62(7):875-882
From a base material of conductive polymer(poly-(3,4-ethylenedioxythiophene):poly(styrenesulfonate),PEDOT:PSS),a flexible and high-conductivity(as low as 45Ω/sq)transparent electrode was fabricated on polydimethylsiloxane elastomer by an acid treatment and transfer process.Combined with the D-sorbitol-doped PEDOT:PSS electric glue,we successfully demonstrated a vacuum-free and ambient lamination fabrication process for semi-transparent perovskite solar cells using triple cation Cs_(0.05)(MA_(0.17)FA_(0.83))_(0.95)Pb(I_(0.83)Br_(0.17))_3perovskite.By this manufacturing-friendly lamination process,we fabricated semitransparent perovskite solar cell devices with power conversion efficiencies up to 16.4%and variable transparencies. 相似文献
104.
Ein elektronenreiches cyclisches (Alkyl)(amino)carben auf Au(111)-, Ag(111)- und Cu(111)-Oberflächen
Anne Bakker Dr. Matthias Freitag Elena Kolodzeiski Peter Bellotti Dr. Alexander Timmer Dr. Jindong Ren Bertram Schulze Lammers Daniel Moock Prof. Dr. Herbert W. Roesky Dr. Harry Mönig Dr. Saeed Amirjalayer Prof. Dr. Harald Fuchs Prof. Dr. Frank Glorius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(32):13745-13749
105.
Dr. Ran Du Dr. Jan-Ole Joswig Dr. René Hübner Lin Zhou Dr. Wei Wei Prof. Yue Hu Prof. Dr. Alexander Eychmüller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8370-8377
Noble-metal aerogels (NMAs) have drawn increasing attention because of their self-supported conductive networks, high surface areas, and numerous optically/catalytically active sites, enabling their impressive performance in diverse fields. However, the fabrication methods suffer from tedious procedures, long preparation times, unavoidable impurities, and uncontrolled multiscale structures, discouraging their developments. By utilizing the self-healing properties of noble-metal aggregates, the freezing-promoted salting-out behavior, and the ice-templating effect, a freeze–thaw method is crafted that is capable of preparing various hierarchically structured noble-metal gels within one day without extra additives. In light of their cleanliness, the multi-scale structures, and combined catalytic/optical properties, the electrocatalytic and photoelectrocatalytic performance of NMAs are demonstrated, which surpasses that of commercial noble-metal catalysts. 相似文献
106.
Ren Yang Zhou Xiaoge Wang Qiuhong Zhao Gaoyang 《Journal of Sol-Gel Science and Technology》2018,85(3):732-742
Journal of Sol-Gel Science and Technology - In this paper, a double-layer coating with both redox and plasmonic electrochromic properties has been designed and deposited on fluorine doped tin oxide... 相似文献
107.
Jun Ren 《International Journal of Theoretical Physics》2009,48(7):2088-2097
In this paper, we study the thermal properties of the inner horizon of a Kerr-Newman black hole. By adopting Damour-Ruffini
method and the thin film model which is developed on the base of brick wall model suggested by ’t Hooft, we calculate the
temperature and the entropy of the inner horizon of a Kerr-Newman black hole. We conclude that the temperature of inner horizon
is positive and the entropy of the inner horizon is proportional to the area of the inner horizon. The cut-off factor is same
as it in calculation of the entropy of the outer horizon, 90β. In addition, we write the integral and differential Bekenstein-Smarr formula as the parameters of the inner horizon. Then,
we discuss that if the contribution of the inner horizon is taken into account to the total entropy of the black hole, the
Nernst theorem can be satisfied. At last, We calculate the tunneling rate of the outer horizon Γ+ and the inner horizon Γ−. The total tunneling rate Γ should be the product of the rates of the outer and inner horizon, Γ=Γ+⋅Γ−. We find that the total tunneling rate is in agreement with the Parikh’s standard result, Γ→exp (ΔS
BH
), and there is no information loss. 相似文献
108.
René Michel 《Extremes》2007,10(3):83-107
The investigation of multivariate generalized Pareto distributions (GPDs) has begun only recently. For further progress with
these distributions simulation methods are an important part. We describe several methods of simulating GPDs, beginning with
an efficient method for the logistic GPD. The algorithm is based on the Shi transformation, which was already used for the
simulation of multivariate extreme value distributions (EVDs) of logistic type. In the sequel another algorithm is presented
simulating a broader class of GPDs. Due to its numerical complexity it is only practicably applicable in low dimensions. A
method is given to generate unconditional GPD random vectors from conditionally GPD distributed random vectors. A short application
of the simulation methods in the analysis of a real hydrological data set concludes the article. The simulation algorithms
are available on the author’s home page .
相似文献
109.
Jihad René Albani 《Journal of fluorescence》2009,19(6):1061-1071
We measured fluorescence lifetimes of L-Tryptophan dissolved in de-ionized water and in ethanol in the absence and the presence
of high progesterone concentrations. The hormone absorbs between 220 and 280 with a peak around 250 nm, while its absorption
is equal to zero beyond 280 nm. Tryptophan excitation spectrum recorded in presence of progesterone shows that the So → 1La transition is completely abolished while the So
→
1Lb transition is not affected. Emission of L-tryptophan in water occurs with two fluorescence lifetimes, 0.40 and 2.8 ns. In
ethanol, three fluorescence lifetimes equal to around 0.2, 1.8 and 4.8 ns were observed. Addition of progesterone to the medium
does not affect any of the fluorescence lifetimes indicating clearly that both transitions could induce tryptophan excitation
and that recorded fluorescence lifetimes could be assigned to sub-structures generated in the excited state. 相似文献
110.