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51.
Experimental evidence has been found for consecutive projectile-target-projectile (triple) and projectile-target-projectile-target (quadruple) "ping-pong" scattering of ionized target electrons in single C+ +Xe collisions at 150 and 233 keV/u impact energies. Distinct signatures of the multiple electron scattering contributions to the high-energy part (300-3400 eV) of the double differential electron spectra have been separated and identified with the help of reference measurements using He+ projectile ions and different calculations. 相似文献
52.
Energy band alignment of SnO2/SrTiO3 epitaxial heterojunction studied by X‐ray photoelectron spectroscopy 下载免费PDF全文
Chang Ke Weiguang Zhu Zheng Zhang Eng Soon Tok Jisheng Pan 《Surface and interface analysis : SIA》2015,47(8):824-827
(200) SnO2//(111) SrTiO3 (STO) epitaxial heterojunctions were fabricated using the laser molecular epitaxy technique. Sharp junction interface was confirmed by the high‐resolution transmission electron microscopy. The valence band offset and conduction band offset of the SnO2/STO heterojunction were determined to be 0.85 ± 0.20 and 0.45 ± 0.20 eV using XPS, respectively. It is found that a type‐II band alignment forms at the SnO2/STO interface. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
53.
Rapid and efficient sensors are essential for effective defense against the emerging threat of bioterrorism and biological warfare. This review article describes several recent immunosensing advances that are relevant to biothreat detection. These highly diverse examples are intended to demonstrate the breadth of these immunochemical sensing systems and platforms while highlighting those technologies that are suitable for pathogen detection. 相似文献
54.
Despite intensive work there are still controversial issues about desorption and adsorption of hydrogen on Si(100)-(2 x 1). In particular, the relative importance of the various interdimer- and intradimer-desorption paths is not clear. Nanosecond-pulse-laser desorption data have been used to argue that the 4H interdimer path is important, while data from thermal-desorption time-of-flight measurements suggest a large translationally hot contribution which cannot arise from the 4H interdimer path. The observation of a translationally hot desorption fraction at low to medium coverage can be accounted for by including the 2H interdimer path in quantum dynamical calculations. In this paper we investigate this issue further and present evidence that supports the inclusion of the intradimer path. Specifically, our results show that the intradimer and 3H interdimer paths provide the major contributions to the translationally hot fraction in the desorbate. Our conclusions are based on density-functional calculations of hydrogen translational excitation, mean-field analysis of thermal-desorption experiments over a range of ramp rate, and Monte Carlo simulations of nanosecond-pulse-laser experiments. 相似文献
55.
Undoped Layered Perovskite Oxynitride Li2LaTa2O6N for Photocatalytic CO2 Reduction with Visible Light 下载免费PDF全文
Takayoshi Oshima Tom Ichibha Ken Sinkou Qin Kanemichi Muraoka Dr. Junie Jhon M. Vequizo Keisuke Hibino Ryo Kuriki Dr. Shunsuke Yamashita Prof. Dr. Kenta Hongo Dr. Tomoki Uchiyama Prof. Dr. Kotaro Fujii Dr. Daling Lu Prof. Dr. Ryo Maezono Prof. Dr. Akira Yamakata Prof. Dr. Hideki Kato Dr. Koji Kimoto Prof. Dr. Masatomo Yashima Prof. Dr. Yoshiharu Uchimoto Prof. Dr. Masato Kakihana Prof. Dr. Osamu Ishitani Prof. Dr. Hiroshi Kageyama Prof. Dr. Kazuhiko Maeda 《Angewandte Chemie (International ed. in English)》2018,57(27):8154-8158
Oxynitrides are promising visible‐light‐responsive photocatalysts, but their structures are almost confined with three‐dimensional (3D) structures such as perovskites. A phase‐pure Li2LaTa2O6N with a layered perovskite structure was successfully prepared by thermal ammonolysis of a lithium‐rich oxide precursor. Li2LaTa2O6N exhibited high crystallinity and visible‐light absorption up to 500 nm. As opposed to well‐known 3D oxynitride perovskites, Li2LaTa2O6N supported by a binuclear RuII complex was capable of stably and selectively converting CO2 into formate under visible light (λ>400 nm). Transient absorption spectroscopy indicated that, as compared to 3D oxynitrides, Li2LaTa2O6N possesses a lower density of mid‐gap states that work as recombination centers of photogenerated electron/hole pairs, but a higher density of reactive electrons, which is responsible for the higher photocatalytic performance of this layered oxynitride. 相似文献
56.
V. A. Nikanorov O. L. Tok S. G. Novikov S. V. Sergeev E. V. Vorontsov I. D. Gridnev D. V. Zverev A. T. Lebedev 《Russian Chemical Bulletin》1997,46(2):350-354
Three approaches to the synthesis ofN-substituted imino-, hydrazono-, and azino-2,5-cyclohexadienylidene systems based on reactions of 4-methyl-4-trichloromethylcyclohexa-2,5-dienone
with aminophenols and hydrazones and condensation of hydrazones ofpara-semiquinoid ketones with carbonyl compounds, including that of the ferrocene series, were realized. The latter reaction,
when applied to 3,6-dibromophenanthrene-9, 10-quinone, was accompanied by quantitative aromatizational molecular rearrangement
with the elimination of the CCl3 group. Using Rh1 complexes as an example, it was shown that the heteroorganic ligands obtained can be used for the synthesis of mixed-ligand
metallocomplexes with triple coordination of the metal atom including simultaneous metal-ligand interactions of the n-, π-,
and σ-types.
The principle of metal-ligand “cascade” appeared as a result of the generalization of two new phenomena of organometallic
sereodynamics, which we have found recently2,3 and have called oxidative and reductive redox-rotation. In the “cascade”, type1 (“metal-ligand-metal”) or type2 (“ligand-metal-ligand”) metallocomplexes, one or several coordinated metal ligand”) metallocomplexes, one or several coordinated
metal atoms capable of concertedly and reversibly changing their valence in the course of intramolecular conformational transformation
are in positions of mutual conjugation.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 363–367, February, 1997. 相似文献
57.
Car-Parrinello molecular dynamics (CPMD) are widely used to investigate the dynamical properties of molecular systems. An important issue in such applications is the dependence of dynamical quantities such as molecular vibrational frequencies upon the fictitious orbital mass μ. Although it is known that the correct Born-Oppenheimer dynamics are recovered at zero μ, it is not clear how these dynamical quantities are to be rigorously extracted from CPMD calculations. Our work addresses this issue for vibrational frequencies. We show that when the system is sufficiently close to the ground state the calculated ionic vibrational frequencies are ω(M) = ω(0M)[1 -C(μ/M)] for small μ/M, where ω(0M) is the Born-Oppenheimer ionic frequency, M the ionic mass, and C a constant that depends upon the ion-orbital coupling force constants. Our analysis also provides a quantitative understanding of the orbital oscillation amplitudes, leading to a relationship between the adiabaticity of a system and the ion-orbital coupling constants. In particular, we show that there is a significant systematic dependence of calculated vibrational frequencies upon how close the CPMD trajectory is to the Born-Oppenheimer surface. We verify our analytical results with numerical simulations for N(2), Sn(2), and H/Si(100)-(2×1). 相似文献
58.
We introduce a new solution for two-person bargaining problems: the iterated egalitarian compromise solution. It is defined by using two prominent bargaining solutions, the egalitarian solution (Kalai, 1977) and the equal-loss solution (Chun, 1988), in an iterative fashion. While neither of these two solutions satisfy midpoint domination – an appealing normative property – we show that the iterated egalitarian compromise solution does so. 相似文献
59.
60.
Characterization of the electronic structure and thermal stability of HfO2/SiO2/Si gate dielectric stack 下载免费PDF全文
X‐ray photoelectron spectroscopy was used to investigate thermal stability of HfO2 on SiO2/Si substrate prepared by atomic layer deposition, followed by annealing at different temperature. Hf silicate and Hf silicide are formed at the interface of HfO2 and SiO2 during deposition. The Hf silicide disappears, while the amount of the Hf silicate is intensified after post‐deposition annealing treatment at 400 °C. Phase separation of the Hf silicate layer occurs when the annealing temperature is over 400 °C, resulting in the Hf silicate decomposition into Si and Hf oxides. Moreover, crystallization at high temperature leads to grain boundaries formation, which deteriorates the gate leakage current, as observed by the electrical measurements. The similar annealing temperature dependence of both internal electric field and the amount of Hf silicate implies that the Hf silicate plays a key role in building up the internal electric field, which is attributed to generation of oxygen vacancies (Vo) in the Hf silicate layer. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献