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21.
This article reviews our approach to render 12CaO · 7Al2O3 (C12A7) electronically active using a new concept of ‘active anion manipulation’, where nanostructures embedded within the
C12A7 crystal lattice are intentionally utilized to generate chemically unstable (‘water-free active’) anions. Anionic active
oxygen radicals, O− and O2−, are formed efficiently in C12A7 cages under high oxygen activity conditions. The configuration and dynamics of O2− in cages are revealed by a combination of continuous-wave and pulsed electron paramagnetic resonance (EPR). It is demonstrated
that metal-loaded C12A7 is a promising oxidation catalyst for syngas (CO + H2) formation from methane. Furthermore, the O− ion, the strongest oxidant among active oxygen species, can be extracted from the cage into an external vacuum by applying
an electric field with thermal assistance, generating a high-density O− beam in the order of μA cm−2. In contrast, heat treatment of C12A7 in a hydrogen atmosphere forms H− ions in the cages. The resultant C12A7:H− exhibits a persistent insulator-conductor conversion upon ultraviolet-light or electron-beam irradiation. The irradiation-induced
conversion mechanism is examined by first-principle theoretical calculations. Furthermore, the presence of a severely reducing
environment causes the complete substitution of electrons for anions in the cages. The resulting C12A7:e−, which exhibits excellent stability and an electrical conductivity greater than 100 S cm−1, is regarded as an ‘electride’, an ionic compound in which electrons serve as anions. The C12A7 electride exhibits a high
potential for applications involving cold cathode and thermal field electron emissions due to its small work function. Electride
fabrication methods suitable for large-scale production via melt processing are described. It is also demonstrated that proton
or inert gas ion implantations into C12A7 thin films at elevated temperatures are effective for both H− and electron doping. 相似文献
22.
23.
Michiaki Matsumoto Atsushi Kado Takayoshi Shiraki Kazuo Kondo Kazuharu Yoshizuka 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(11):1712-1716
BACKGROUND: Diols that can be produced biologically have attracted much attention because of the increased cost of producing them chemically. The cost of separating the diols from the broth forms a major part of the total cost of microbial production. Reactive extraction using organoboronate is one promising method for recovering diols from the dilute aqueous solution. RESULTS: A basic investigation of solvent extraction of diols was conducted at 303 K employing phenylboronic acid and trioctylmethylammonium chloride as coextractants in the mixed solvent. Both the tetrahedral boronate anion complex and trigonal boronate neutral complex were extracted. 1,3‐diols and vicinal diols were extracted, but 1,4‐diol was not extracted. Extraction equilibrium constants were correlated with the enthalpies of formation of the complexes, which were calculated by molecular modeling with semi‐empirical molecular orbital calculations considering the solvent effect. CONCLUSION: The complex extraction behaviour of diols with phenylboronic acid and quaternary ammonium salt can be predicted by using the quantitative structure–property relationship (QSPR). Copyright © 2009 Society of Chemical Industry 相似文献
24.
25.
Origin of the Red Color of Satsuma Copper-Ruby Glass as Determined by EXAFS and Optical Absorption Spectroscopy 总被引:1,自引:0,他引:1
Izumi Nakai Chiya Numako Hideo Hosono Kazuo Yamasaki 《Journal of the American Ceramic Society》1999,82(3):689-695
The origin of the ruby color of Satsuma glass, a famous copper-ruby glass produced in Japan in the mid-19th century, has been examined by electron microprobe analysis (EPMA), X-ray absorption fine structure (XAFS), and optical absorption spectroscopy analyses. Cu K XAFS analysis reveals that the major component of copper in the ruby glass consists of Cu(I) ions in the glass structure. This species is distinct from Cu2 O (cuprite), which we conclude is not responsible for the ruby color. Optical absorption spectra measured at 300 and 77 K clearly distinguishes the absorptions due to the colloidal particles of metallic copper and Cu2 O. It is concluded that the trace amount of copper in the ruby glass, which is below the detection limit of the EPMA and XAFS techniques, exists as metallic copper particles of nanometer size and is responsible for the ruby-red appearance of the Satsuma glass. 相似文献
26.
Impact of fertilizer on a small watershed of Lake Biwa: use of sulfur and strontium isotopes in environmental diagnosis 总被引:4,自引:0,他引:4
Hosono T Nakano T Igeta A Tayasu I Tanaka T Yachi S 《The Science of the total environment》2007,384(1-3):342-354
Sulfur and strontium isotopes (delta(34)S and (87)Sr/(86)Sr) were determined in 39 river water samples collected over three different cultivation periods (April, May, and June), and in several materials used for comparison (fertilizers, detergents, soils, irrigation and agricultural waters), to evaluate the impact of fertilizers on a small agricultural watershed of Lake Biwa, in central Japan. delta(34)S values in river water decreased (from +5.8 to -2.0 per thousand) with increasing SO(4) concentrations (3.8 to 93.2 ppm) from upstream to downstream of the watershed. Comparison of river water S isotopes with those of possible source materials indicates that the enrichment of SO(4) can be attributed to the dissolution of two kinds of fertilizers: (1) compound fertilizers commonly used in this area and (2) ammonium sulfate which is applied on a small scale. In contrast, (87)Sr/(86)Sr values of river water decreased with time from April (avg. 0.71163), through May (avg. 0.71139), to June (avg. 0.71127). The tendency of the sample plots on the (87)Sr/(86)Sr vs. 1/Sr diagram suggests a time-dependent increase in the contribution of soil water to the river, which is partly affected by the Sr-bearing fertilizers. It is suggested that a maximum of 25% of dissolved Sr is derived from these fertilizers, while more than 75% of it is of rock origin. Mass balance calculations permitted us to evaluate the proportion of fertilizer contribution in each river. Combined use of S and Sr isotopes together with concentration data could be a new environmental diagnosis technique for rivers and soils in localized watersheds. 相似文献
27.
The inhibitory effects of cultured milk using 76 strains of lactic acid bacteria isolated from milk products were investigated on the mutagenicity of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P2), a tryptophan pyrolysate for Salmonella typhimurium TA98. Each cultured milk sample displayed its characteristic antimutagenic effect against the mutagenicity of Trp-P2. The milk cultured with Lactobacillus acidophilus LA106 (LA2) showed the highest inhibition of 82.1% among the strains used. Milk samples cultured with Lactococcus lactis subsp. lactis, Lll103 (10-3) and Lll102 (KM) also exhibited higher inhibition percentages. 相似文献
28.
Manabu Iguchi Tsuneo Kondoh Zen-Ichiro Morita Keiji Nakajima Kazuharu Hanazaki Tomomasa Uemura Fujio Yamamoto 《Metallurgical and Materials Transactions B》1995,26(2):241-247
Laser Doppler velocimeter (LDV) measurements were made to clarify the fluid flow behavior in a bath subject to centric bottom
gas injection. Correlations of the axial mean velocity and turbulence components in the gas-liquid two-phase flow region,i.e., in the bubbling jet region, were proposed as functions of the inner diameter of nozzle, gas flow rate, and densities of
gas and liquid. Measured values of the flow rate, momentum, and kinetic energy of water rising upward were approximated satisfactorily
by these empirical correlations. In addition, the Reynolds shear stress was calculated and compared with measured values.
Formerly Graduate Student, Osaka University, 相似文献
29.
Hara T. Fukuda K. Kanazawa K. Shibata N. Hosono K. Maejima H. Nakagawa M. Abe T. Kojima M. Fujiu M. Takeuchi Y. Amemiya K. Morooka M. Kamei T. Nasu H. Chi-Ming Wang Sakurai K. Tokiwa N. Waki H. Maruyama T. Yoshikawa S. Higashitani M. Pham T.D. Yupin Fong Watanabe T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):161-169
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration. 相似文献
30.
Liquid Crystals: Liquid‐Crystalline Electrolytes for Lithium‐Ion Batteries: Ordered Assemblies of a Mesogen‐Containing Carbonate and a Lithium Salt (Adv. Funct. Mater. 8/2015)
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