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Helena Tllez John Druce Allen Hall Tatsumi Ishihara John Kilner Angus Rockett 《Progress in Photovoltaics: Research and Applications》2015,23(10):1219-1227
Cu(In,Ga)Se2 (CIGS) single‐crystal epitaxial films have been analyzed by low energy ion scattering, which is sensitive to exactly the outermost surface atomic layer, to determine the surface chemistry as a function of preparation conditions. The samples were grown by a hybrid sputtering and evaporation method on cation (A) or anion (B) terminated (111) GaAs substrates and had smooth surfaces. The samples were exposed to excited atomic oxygen or hydrogen beams or were sputtered with 500 eV Ar+ ions. Atomic O* treatment resulted in an otherwise clean, oxidized surface including all film constituents. Atomic H* resulted in strong enhancement of the surface Ga population, probably due to a preexisting Ga native oxide in the outermost atomic layer. Sputtering produced a clean surface that was closest to the bulk composition of the film as measured by energy‐dispersive spectroscopy. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
384.
ABSTRACT: Antioxidant activity of milk products and ingredients were investigated by measuring the induction time of the Rancimat test. Butter serum showed an inhibitory effect of fish oil oxidation in the presence of δ-tocopherol, which was enhanced by the addition of sucrose ester of fatty acid (SEF). This antioxidant-enhancing effect was dependent on hydrophilic-lipophilic balance (HLB) ranging from 1 to 15 of SEF. HLB 2 of SEF enhanced it most effectively. On the contrary, whole milk, skim milk, buttermilk, and whey protein concentrate did not show the inhibitory effect, and these were not improved by SEF. 相似文献
385.
Potassium salts were added to the catalyst prepared by ion exchange of KL with [Pt(NH3)4]Cl2 and the effect of their counter anion on the activity and selectivity for hexane aromatization was studied. The catalyst to which KF was added showed the highest activity and selectivity for benzene formation; methylcyclopentane and hydroisomerization products were negligible. Although the catalyst with KCl added also exhibited excellent performance, the catalysts with KBr or KI added gave rise to low hexane conversion and benzene yield. Infra-red spectra of adsorbed CO revealed that the presence of the low frequency C-O stretching band is closely related to catalytic performance of the Pt/KL series catalysts. The electron-rich Pt site formed through the interaction with KF or KCl may be responsible for the high activity and selectivity for hexane aromatization. 相似文献
386.
387.
Izumi Tsuda Kazue Setoguchi Noriyuki Tatsumi 《Journal of Automated Methods and Management in Chemistry》1990,12(3):104-107
Two data interpretation programs incorporated into two different automated blood cell counters were evaluated. The programs analysed size distribution histograms for screening for abnormal specimens. The messages given by the programs were ‘normal’, ‘abnormal’ and ‘suspect’. ‘Abnormal’ messages meant abnormalities in the values of the measured parameters. ‘Suspect’ messages were given when the histograms showed either a possibility of the existence of abnormal blood cells, or an abnormal level of such cells; re-examination by a manual method was necessary for such specimens. For reference, the manual differential was done. The false-negative rate for each kind of message was less than 10% and efficiency was about 90%. These programs were helpful in avoiding unnecessary manual observations in reducing the workload in a routine clinical laboratory. 相似文献
388.
Aleksandar Staykov Helena Tellez John Druce Ji Wu Tatsumi Ishihara John Kilner 《Science and Technology of Advanced Materials》2018,19(1):221-230
Surface reactivity and near-surface electronic properties of SrO-terminated SrTiO3 and iron doped SrTiO3 were studied with first principle methods. We have investigated the density of states (DOS) of bulk SrTiO3 and compared it to DOS of iron-doped SrTiO3 with different oxidation states of iron corresponding to varying oxygen vacancy content within the bulk material. The obtained bulk DOS was compared to near-surface DOS, i.e. surface states, for both SrO-terminated surface of SrTiO3 and iron-doped SrTiO3. Electron density plots and electron density distribution through the entire slab models were investigated in order to understand the origin of surface electrons that can participate in oxygen reduction reaction. Furthermore, we have compared oxygen reduction reactions at elevated temperatures for SrO surfaces with and without oxygen vacancies. Our calculations demonstrate that the conduction band, which is formed mainly by the d-states of Ti, and Fe-induced states within the band gap of SrTiO3, are accessible only on TiO2 terminated SrTiO3 surface while the SrO-terminated surface introduces a tunneling barrier for the electrons populating the conductance band. First principle molecular dynamics demonstrated that at elevated temperatures the surface oxygen vacancies are essential for the oxygen reduction reaction. 相似文献
389.
N. Sato T. Haruyama K. Kuroda M. Ohashi T. Shintomi D. Tatsumi C. Taylor T. Tomaru A. Yamamoto 《低温学》2003,43(7):425-429
We measured forces applied by an actuator with a YBa2Cu3O7 (YBCO) film at near 77 K for the Large-scale Cryogenic Gravitational-wave Telescope (LCGT) project. An actuator consisting of both a YBCO film of 1.6 μm thickness and 0.81 cm2 area and a solenoid coil exerted a force of up to 0.2 mN on a test mass. The presented actuator system can be used to displace the mirror of LCGT for fringe lock of the interferometer. 相似文献
390.
Ni‐Fe Nitride Nanoplates on Nitrogen‐Doped Graphene as a Synergistic Catalyst for Reversible Oxygen Evolution Reaction and Rechargeable Zn‐Air Battery 下载免费PDF全文
Yuchi Fan Shintaro Ida Aleksandar Staykov Taner Akbay Hidehisa Hagiwara Junko Matsuda Kenji Kaneko Tatsumi Ishihara 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(25)
Obtaining bifunctional electrocatalysts with high activity for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is a main hurdle in the application of rechargeable metal‐air batteries. Earth‐abundant 3d transition metal‐based catalysts have been developed for the OER and ORR; however, most of these are based on oxides, whose insulating nature strongly restricts their catalytic performance. This study describes a metallic Ni‐Fe nitride/nitrogen‐doped graphene hybrid in which 2D Ni‐Fe nitride nanoplates are strongly coupled with the graphene support. Electronic structure of the Ni‐Fe nitride is changed by hybridizing with the nitrogen‐doped graphene. The unique heterostructure of this hybrid catalyst results in very high OER activity with the lowest onset overpotential (150 mV) reported, and good ORR activity comparable to that for commercial Pt/C. The high activity and durability of this bifunctional catalyst are also confirmed in rechargeable zinc‐air batteries that are stable for 180 cycles with an overall overpotential of only 0.77 V at 10 mA?2. 相似文献