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101.
102.
A Doping Technique that Suppresses Undesirable H2 Evolution Derived from Overall Water Splitting in the Highly Selective Photocatalytic Conversion of CO2 in and by Water 下载免费PDF全文
Prof. Dr. Kentaro Teramura Zheng Wang Dr. Saburo Hosokawa Prof. Dr. Yoshihisa Sakata Prof. Dr. Tsunehiro Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(32):9906-9909
Photocatalytic conversion of CO2 to reduction products, such as CO, HCOOH, HCHO, CH3OH, and CH4, is one of the most attractive propositions for producing green energy by artificial photosynthesis. Herein, we found that Ga2O3 photocatalysts exhibit high conversion of CO2. Doping of Zn species into Ga2O3 suppresses the H2 evolution derived from overall water splitting and, consequently, Zn‐doped, Ag‐modified Ga2O3 exhibits higher selectivity toward CO evolution than bare, Ag‐modified Ga2O3. We observed stoichiometric amounts of evolved O2 together with CO. Mass spectrometry clarified that the carbon source of the evolved CO is not the residual carbon species on the photocatalyst surface, but the CO2 introduced in the gas phase. Doping of the photocatalyst with Zn is expected to ease the adsorption of CO2 on the catalyst surface. 相似文献
103.
Ribeiro Geyse Adriana Corrêa da Rocha Cláudia Quintino Veloso William Barros Dantas Luiza Maria Ferreira Richter Eduardo Mathias da Silva Iranaldo Santos Tanaka Auro Atsushi 《Journal of Solid State Electrochemistry》2020,24(8):1759-1768
Journal of Solid State Electrochemistry - Rapid methods using batch injection analysis (BIA) with amperometric detection were developed for the determination of quercetin extracted from the... 相似文献
104.
Masahito Sekiguchi Hiromichi Tanaka Noriaki Takami Akiya Ogawa Ilhyong Ryu Noboru Sonoda 《Heteroatom Chemistry》1991,2(3):427-430
The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se2− and Se22−), the alkylation of which provided dialkyl selenides and diselenides, respectively, in excellent yields. 相似文献
105.
Hitoshi Tanaka 《Macromolecular Symposia》1994,84(1):137-143
Magnetism of hydroanilino ladder polymer and indigo polymer which were prepared by the oxidative polyrecombination of captodative substituted methane and indoxyl, respectively, was studied by ESR spectroscopy and magnetic susceptibility measurement. It was found that both spin polymers contained domains with high spin state in their structures and their spins were much more ordered with decreasing temperature. 相似文献
106.
We introduce a quantum key distribution protocol using mean multi-kings’ problem. Using this protocol, a sender can share a bit sequence as a secret key with receivers. We consider a relation between information gain by an eavesdropper and disturbance contained in legitimate users’ information. In BB84 protocol, such relation is known as the so-called information disturbance theorem. We focus on a setting that the sender and two receivers try to share bit sequences and the eavesdropper tries to extract information by interacting legitimate users’ systems and an ancilla system. We derive trade-off inequalities between distinguishability of quantum states corresponding to the bit sequence for the eavesdropper and error probability of the bit sequence shared with the legitimate users. Our inequalities show that eavesdropper’s extracting information regarding the secret keys inevitably induces disturbing the states and increasing the error probability. 相似文献
107.
108.
When we consider an error model in a quantum computing system, we assume a parametric model where a prepared qubit belongs. Keeping this in mind, we focus on the evaluation of the amount of information we obtain when we know the system belongs to the model within the parameter range. Excluding classical fluctuations, uncertainty still remains in the system. We propose an information quantity called purely quantum information to evaluate this and give it an operational meaning. For the qubit case, it is relevant to the facility location problem on the unit sphere, which is well known in operations research. For general cases, we extend this to the facility location problem in complex projective spaces. Purely quantum information reflects the uncertainty of a quantum system and is related to the minimum entropy rather than the von Neumann entropy. 相似文献
109.
Manabu KuroboshiTomotake Yano Shogo KamenoueHiromu Kawakubo Hideo Tanaka 《Tetrahedron》2011,67(32):5825-5831
Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode, wherein Al3+, which was electrogenerated at the anode would react as a Lewis acid with triphenylphosphine dichloride to afford tetra-coordinate chlorotriphenylphosphonium species and subsequent two-electron reduction at the cathode would give triphenylphosphine. One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide with oxalyl chloride and subsequent electroreduction. In a similar manner, some tetra-coordinate triphenylphosphonium species derived from triphenylphosphine oxide were reduced electrochemically to triphenylphosphine in moderate yields. 相似文献
110.
Application of digital image analysis (DIA) to polymer blends morphology is discussed with examples. Various operations in DIA including two-dimensional Fourier transformation (2DFT), intensity distribution, recursive region extraction, etc. are applied to morphology of polymer blends due to spinodal decomposition (SD), nucleation 6 growth (NG), and eutectic solidification (ES). Merits and drawbacks of DIA to study polymer blends morphology are discussed and the possibility of future development is presented. 相似文献