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121.
Using the uniform most powerful unbiased test, we observed the sales distribution of consumer electronics in Japan on a daily basis and report that it follows both a lognormal distribution and a power-law distribution and depends on the state of the market. We show that these switches occur quite often. The underlying sales dynamics found between both periods nicely matched a multiplicative process. However, even though the multiplicative term in the process displays a size-dependent relationship when a steady lognormal distribution holds, it shows a size-independent relationship when the power-law distribution holds. This difference in the underlying dynamics is responsible for the difference in the two observed distributions. 相似文献
122.
Ryohei Kaneko Dr. Yoshimitsu Sagara Dr. Shouhei Katao Prof. Nobuyuki Tamaoki Prof. Dr. Christoph Weder Prof. Hideyuki Nakano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(24):6162-6169
The mechanoresponsive behavior and photochemical response of a new bis(cyanostyryl)benzene fluorophore (CSB-5) were investigated. Green fluorescence with λem,max of 507 nm was found for CSB-5 in chloroform solution, mirroring the behavior of a previously reported similar dye (CSB-6). Alternatively, crystalline samples of CSB-5 exhibited orange fluorescence with λem,max of 620 nm, attributable to excimer emission. Although the emission color change was not clearly noticeable by naked eye, CSB-5 exhibited mechanochromic luminescence, due to transformation into the amorphous state upon grinding the crystalline powder. Interestingly, rubbed films of CSB-5 prepared on glass substrates exhibited a pronounced emission color change from orange to green when exposed to UV light. This response is the result of a photochemical reaction that occurs in the amorphous state and which causes a decrease of the excimer emission sites so that the emission color changes from excimer to monomer. The crystalline material did not display such a photoinduced emission color change and the difference in photochemical reactivity between crystalline and amorphous states was exploited to pattern the emission color of rubbed films. 相似文献
123.
Yonkil Jeong Masato Hirade Ryohei Kokawa Hirofumi Yamada Kei Kobayashi Noriaki Oyabu Toyoko Arai Akira Sasahara Masahiko Tomitori 《Current Applied Physics》2012,12(2):581-584
Local interaction imaging of cleaved InAs surface (110) using a high aspect ratio (HAR) SiGe quantum dot (QD) probe was demonstrated by frequency-modulation mode noncontact atomic force microscopy under atmospheric pressure. The local contrast image with pronounced brightness is mainly attributed to no contact potential difference between the HAR SiGe-QD probe apex and the sample surface, and low frequency-change of the HAR SiGe-QD probe. 相似文献
124.
Fumihiko Kitagawa Kana Tanigawa‐Joh Satomi Terashita Ryohei Fujiki Isoshi Nukatsuka Kenji Sueyoshi Koji Otsuka 《Electrophoresis》2019,40(18-19):2478-2483
In this study, we found that the polarity switching was effective to enrich and separate fluorescent analytes which have weakly‐dissociated groups in a floating platinum electrode (width, 50 µm; thickness, 2.5 µm)‐integrated straight‐channel in microchip electrophoresis (MCE). In the straight channel filled with an Alexa Flour 488 (AF488) solution, a sharp peak was observed after the polarity inversion with a 530‐fold enhancement of the sensitivity relative to the conventional MCE analysis. By using a fluorescent pH indicator, we verified that a sharp high‐pH zone was generated nearby the floating electrode and moved toward the anode with maintaining the high pH, which induced the sample enrichment like a dynamic pH junction mechanism. In the floating electrode‐embedded channel, the mixture of AF488‐labeled proteins was also well concentrated and separated within 100 s. 相似文献
125.
Ryohei Kokawa Dr. Masahiro Ohta Prof. Akira Sasahara Prof. Hiroshi Onishi 《化学:亚洲杂志》2012,7(6):1251-1255
A catalyst model comprising platinum nanoparticles deposited on a TiO2(110) wafer was prepared in a vacuum, transferred in air, and characterized with a Kelvin probe force microscope placed in a N2 environment. The topography and local work function of individual nanoparticles were observed with single‐nanometer resolution in the N2 environment of one atmosphere pressure. Some nanoparticle presented positive shifts of work function relative to that of the TiO2 surface, while the others showed negative shifts. This finding suggests heterogeneous properties of the nanoparticles exposed to air and then N2. The ability of the advanced microscope was demonstrated in observing the work function of metal nanoparticles on a metal oxide support even in the presence of vapor environments. 相似文献
126.
Dr. Ryohei Akiyoshi Hikaru Zenno Dr. Yoshihiro Sekine Dr. Manabu Nakaya Prof. Motoko Akita Dr. Daisuke Kosumi Prof. Leonard F. Lindoy Prof. Shinya Hayami 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(5):e202103367
Magnetoelectric (ME) materials exhibiting coupled electric and magnetic properties are of significant interest because of their potential use in memory storage devices, new sensors, or low-consumption devices. Herein, we report a new category of ME material that shows liquid crystal (LC), ferroelectric (FE), and field-induced single molecule magnet (SMM) behaviors. Co(II) complex incorporating alkyl chains of type [Co(3C16-bzimpy)2](BF4)2 ( 1 ; 3C16-bzimpy=2,2’-(4-hexadecyloxy-2,6-diyl)bis(1-hexadecyl-1H-benzo[d]imidazole)) displayed a chiral smectic C mesophase in the temperature range 321 K–458 K, in which distinct FE behavior was observed, with a remnant polarization (88.3 nC cm−2). Complex 1 also exhibited field-induced slow magnetic relaxation behavior that reflects the large magnetic anisotropy of the Co(II) center. Furthermore, the dielectric property of 1 was able to be tuned by an external magnetic field occurring from both spin-lattice coupling and molecular orientational variation. Clearly, this multifunctional compound, combining LC, FE, and SMM properties, represents an entry to the development of a range of next-generation ME materials. 相似文献
127.
128.
Ryohei Ogawa Sung-il Lee Hironori Izumi Go Kagiya Toru Yohsida Akihiko Watanabe Akihiro Morii Satoshi Kakutani Takashi Kondo Loreto B. Feril Tetsuya Ishimoto 《Ultrasonics sonochemistry》2009,16(3):379-386
We previously developed artificial promoters that were activated in response to X-ray irradiation. Sonication with 1.0 MHz ultrasound that causes intracellular oxidative stress was found to activate some of these promoters though to lesser degrees. The most sensitive one among these promoters showed intensity- and duration-dependent activations by sonication. In addition, its activation by sonication was attenuated when N-acetyl cysteine was present, suggesting the involvement of intracellular oxidative stress in the activation mechanism. Improved promoters for sensitivity to X-ray irradiation were also found more sensitive to sonication. The most improved one showed 6.0 fold enhancement after sonication with 1.0 MHz ultrasound at 1.0 W/cm2 for 60 s. This enhancement was also attenuated with the presence of N-acetyl cysteine. When stably transfected HeLa cells with the most sensitive promoter were transplanted on to mice and sonicated, luciferase activity by the promoter increased to 1.35 fold in average though it was not statistically significant compared to control. Although gene regulation in vivo by sonication was not clear, this is the first report on artificially constructed promoters responsive to ultrasound. 相似文献
129.
Artificial peaks in energy dispersive X‐ray spectra: sum peaks,escape peaks,and diffraction peaks 下载免费PDF全文
Sum peaks, escape peaks, and diffraction peaks are considered artificial or spurious peaks in energy dispersive X‐ray spectrometry. Experimental examples are given, which showed that escape and diffraction peaks can add up to become sum peaks. These artificial peaks are not weak, and great care must be taken to differentiate them from peaks due to impurity or trace elements. The relationship between the intensity of a sum peak and the original peaks is illustrated using computer simulation as well as probability theory. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
130.
Minoru Toriumi Ryohei Katooka Kazuko Yui Toshitaka Funazukuri Chang Yi Kong Seiichiro Kagei 《Fluid Phase Equilibria》2010
Infinite dilution binary diffusion coefficients, D12, of ferrocene, 1,1′-dimethylferrocene and ethylferrocene in hexane, cyclohexane and ethanol at 313.2 K and pressures from 0.2 to 19 MPa, in acetonitrile at 298.2–333.2 K and 0.2 MPa, and various metallic acetylacetonate, acac, complexes such as Co(acac)3, Ru(acac)3, Rh(acac)3, Pd(acac)2 and Pt(acac)2 mainly in ethanol at 313.2 K and 0.2 MPa were measured by the Taylor dispersion method. The D12 values in m2 s−1 for the three ferrocenes in the present study and those of ferrocene and 1,1′-dimethylferrocene in supercritical carbon dioxide in our previous studies were represented by the modified hydrodynamic equation over a wide range of viscosity: M0.5D12/T = 1.435 × 10−13η−0.8446 with average absolute relative deviation of 2.40% for 316 data points, where M is the solute molecular weight, T is the temperature in K, η is the solvent viscosity in Pa s. Although the D12 values for the acac complexes were roughly represented by the above hydrodynamic equation, the accuracies were lower because they were dependent on not solute molecular weight but the number of acac ligand in the complex molecules. 相似文献