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991.
Li ZhangYoshio Hashimoto Toshinori TaishiIsao Nakamura Qing-Qing Ni 《Applied Surface Science》2011,257(15):6577-6582
A novel flower-shaped Bi2O3 superstructure has been successfully synthesized by calcination of the precursor, which was prepared via a citric acid assisted hydrothermal process. The precursor and Bi2O3 were characterized with respect to morphology, crystal structure and elemental chemical state by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was shown that both the precursor and Bi2O3 flower-shaped superstructure were constructed of numerous nanosheets while the nanosheets consisted of a great deal of nanoparticles. Furthermore, key factors for the formation of the superstructures have been proposed; a mechanism for the growth of the superstructure has been presented based on the FESEM investigation of different growth stages. 相似文献
992.
Koji Nagata Tadao Nakamura Han Geurdes Josep Batle Soliman Abdalla Ahmed Farouk Do Ngoc Diep 《International Journal of Theoretical Physics》2018,57(4):973-980
An interpretation of quantum mechanics is discussed. It is assumed that quantum is energy. An algorithm by means of the energy interpretation is discussed. An algorithm, based on the energy interpretation, for fast determining a homogeneous linear function f(x) := s.x = s 1 x 1 + s 2 x 2 + ? + s N x N is proposed. Here x = (x 1, … , x N ), x j ∈ R and the coefficients s = (s 1, … , s N ), s j ∈ N. Given the interpolation values \((f(1), f(2),...,f(N))=\vec {y}\), the unknown coefficients \(s = (s_{1}(\vec {y}),\dots , s_{N}(\vec {y}))\) of the linear function shall be determined, simultaneously. The speed of determining the values is shown to outperform the classical case by a factor of N. Our method is based on the generalized Bernstein-Vazirani algorithm to qudit systems. Next, by using M parallel quantum systems, M homogeneous linear functions are determined, simultaneously. The speed of obtaining the set of M homogeneous linear functions is shown to outperform the classical case by a factor of N × M. 相似文献
993.
Koji Nagata Tadao Nakamura Han Geurdes Josep Batle Soliman Abdalla Ahmed Farouk 《International Journal of Theoretical Physics》2018,57(6):1605-1611
We present a new method of more speedily calculating a multiplication by using the generalized Bernstein-Vazirani algorithm and many parallel quantum systems. Given the set of real values \(\{a_{1},a_{2},a_{3},\ldots ,a_{N}\}\) and a function \(g:\textbf {R}\rightarrow \{0,1\}\), we shall determine the following values \(\{g(a_{1}),g(a_{2}),g(a_{3}),\ldots , g(a_{N})\}\) simultaneously. The speed of determining the values is shown to outperform the classical case by a factor of \(N\). Next, we consider it as a number in binary representation; M1 = (g(a1),g(a2),g(a3),…,g(a N )). By using \(M\) parallel quantum systems, we have \(M\) numbers in binary representation, simultaneously. The speed of obtaining the \(M\) numbers is shown to outperform the classical case by a factor of \(M\). Finally, we calculate the product; \( M_{1}\times M_{2}\times \cdots \times M_{M}. \) The speed of obtaining the product is shown to outperform the classical case by a factor of N × M. 相似文献
994.
Shinro Yasui Md. Mizanur Rahman Badal Shinjiro Kobayashi Masaaki Mishima 《Journal of Physical Organic Chemistry》2014,27(12):967-972
Laser flash photolysis‐time‐resolved infrared spectroscopy (LFP‐TRIR) was performed on an acetonitrile or dichloromethane solution of triarylphosphines, Ar3P, in air. A transient spectrum consisting of several absorption bands appeared in the region of 1050–1300 cm?1 on the TRIR on a microsecond timescale, which disappeared on a millisecond timescale. To identify the observed transient intermediate, the IR spectra of possible intermediates of the photoreaction were simulated by theoretical calculations based on density functional theory (DFT). The IR spectrum simulated for the phosphine peroxidic radical cation, Ar3P+OO?, well predicted the observed IR spectrum, showing that Ar3P+OO? is formed as a transient intermediate upon the LFP of Ar3P in air. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
Shingo Kato Kakuya Kitagawa Yeonyee E. Yoon Hiroshi Nakajima Motonori Nagata Shinichi Takase Shiro Nakamori Masaaki Ito Hajime Sakuma 《Magnetic resonance imaging》2014
Purpose
The purposes of this study were to evaluate the reproducibility for measuring the cold pressor test (CPT)-induced myocardial blood flow (MBF) alteration using phase-contrast (PC) cine MRI, and to determine if this approach could detect altered MBF response to CPT in smokers.Materials and methods
After obtaining informed consent, ten healthy male non-smokers (mean age: 28 ± 5 years) and ten age-matched male smokers (smoking duration ≥ 5 years, mean age: 28 ± 3 years) were examined in this institutional review board approved study. Breath-hold PC cine MR images of the coronary sinus were obtained with a 3 T MR imager with 32 channel coils at rest and during a CPT performed after immersing one foot in ice water. MBF was calculated as coronary sinus flow divided by the left ventricular (LV) mass which was given as a total LV myocardial volume measured on cine MRI multiplied by the specific gravity (1.05 g/mL).Results
In non-smokers, MBF was 0.86 ± 0.25 mL/min/g at rest, with a significant increase to 1.20 ± 0.36 mL/min/g seen during CPT (percentage change of MBF (?MBF (%)); 39.2% ± 14.4%, p < 0.001). Inter-study reproducibility for ?MBF (%) measurements by different MR technologist was good, as indicated by the intraclass correlation coefficient of 0.93 and reproducibility coefficient of 10.5%. There was no significant difference between smokers and non-smokers for resting MBF (0.85 ± 0.32 mL/min/g, p = 0.91). However, ?MBF (%) in smokers was significantly reduced (-4.0 ± 32.2% vs. 39.2 ± 14.4%, p = 0.011).Conclusion
PC cine MRI can be used to reproducibly quantify MBF response to CPT and to detect impaired flow response in smokers. This MR approach may be useful for monitoring the sequential change of coronary blood flow in various potentially pathologic conditions and for investigating its relationship with cardiovascular risk. 相似文献996.
Raivo Stern Ivo Heinmaa Enno Joon Alexander A. Tsirlin Hiroyuki Nakamura Tsuyoshi Kimura 《Applied magnetic resonance》2014,45(11):1253-1260
We present low-temperature (low-T, sub-liquid-N2) high-speed high-resolution 29Si solid-state (cryoMAS) nuclear magnetic resonance studies on a model 2D-BEC quantum magnet BaCuSi2O6, known also as Han Purple. We observe broadened 29Si lines below the well-established 100 K structural phase transition confirming the existence of inhomogeneities at low temperatures. Interestingly, the low-T spectra of \({\mathrm{BaCuSi}}_{2}{\mathrm{O}}_{6}\) closely resemble those of the novel compound Ba2CoSi2O6Cl2 taken at room temperature. This suggests that the Co compound features structural modulations or inhomogeneities already at room temperature. The low-T crystal structure and magnetism of \({\mathrm{BaCuSi}}_{2}{\mathrm{O}}_{6}\) are more complex than previously believed, and deserve further investigation. 相似文献
997.
Tetsuya Shimogaki Taihei Ofuji Norihiro Tetsuyama Kota Okazaki Mitsuhiro Higashihata Daisuke Nakamura Hiroshi Ikenoue Tanemasa Asano Tatsuo Okada 《Applied Physics A: Materials Science & Processing》2014,114(2):625-629
The effect of high repetition rate pulsed laser annealing with a KrF excimer laser on the optical properties of phosphorus-ion-implanted zinc oxide nanorods has been investigated. The recovery levels of phosphorus-ion-implanted zinc oxide nanorods have been measured by photoluminescence spectra and cathode luminescence images. Cathode luminescence disappeared over 300 nm below the surface due to the damage caused by ion implantation with an acceleration voltage of 25 kV. When the annealing was performed at a low repetition rate of the KrF excimer laser, cathode luminescence was recovered only in a shallow area below the surface. The depth of the annealed area was increased along with the repetition rate of the annealing laser. By optimizing the annealing conditions such as the repetition rate, the irradiation fluence and so on, we have succeeded in annealing the whole damaged area of over 300 nm in depth and in observing cathode luminescence. Thus, the effectiveness of high repetition rate pulsed laser annealing on phosphorus-ion-implanted zinc oxide nanorods was demonstrated. 相似文献
998.
Zhou XJ Shi J Yoshida T Cuk T Yang WL Brouet V Nakamura J Mannella N Komiya S Ando Y Zhou F Ti WX Xiong JW Zhao ZX Sasagawa T Kakeshita T Eisaki H Uchida S Fujimori A Zhang Z Plummer EW Laughlin RB Hussain Z Shen ZX 《Physical review letters》2005,95(11):117001
High resolution angle-resolved photoemission spectroscopy data along the (0,0)-(pi,pi) nodal direction with significantly improved statistics reveal fine structure in the electron self-energy of the underdoped (La2-xSrx)CuO4 samples in the normal state. Fine structure at energies of (40-46) meV and (58-63) meV, and possible fine structure at energies of (23-29) meV and (75-85) meV, have been identified. These observations indicate that, in (La2-xSrx)CuO4, more than one bosonic modes are involved in the coupling with electrons. 相似文献
999.
Removal of phosphate by aluminum oxide hydroxide 总被引:17,自引:0,他引:17
Tanada S Kabayama M Kawasaki N Sakiyama T Nakamura T Araki M Tamura T 《Journal of colloid and interface science》2003,257(1):135-140
The development and manufacture of an adsorbent to remove phosphate ion for the prevention of eutrophication in lakes are very important. The characteristics of phosphate adsorption onto aluminum oxide hydroxide were investigated to estimate the adsorption isotherms, the rate of adsorption, and the selectivity of adsorption. Phosphate was easily adsorbed onto aluminum oxide hydroxide, because of the hydroxyl groups. The adsorption of phosphate onto aluminum oxide hydroxide was influenced by pH in solution: the amount adsorbed was greatest at pH 4, ranging with pH from 2 to 9. The optimum pH for phosphate removal by aluminum oxide hydroxide is 4. The selectivity of phosphate adsorption onto aluminum oxide hydroxide was evaluated based on the amount of phosphate ion adsorbed onto aluminum oxide hydroxide from several anion complex solutions. It is phosphate that aluminum oxide hydroxide can selectively adsorb. The selectivity of phosphate onto aluminum oxide hydroxide was about 7000 times that of chloride. This result indicated that the hydroxyl groups on aluminum oxide hydroxide have selective adsorptivity for phosphate and could be used for the removal of phosphate from seawater. 相似文献
1000.
A homogeneous and disordered assembly of densely packed nanocrystals 2-3 nm in size was synthesized at room temperature in an aqueous solution without the assistance of any organic molecules. The assembled nanocrystals of titanium oxides, such as anatase titanium dioxide, sodium titanate, and a solid solution with rutile tin dioxide, formed macroscopic transparent objects 2-5 mm in size. In general, it is not easy to obtain homogeneous and disordered assembly of nanocrystals without assistance of any organic molecules for the inhibition of inhomogeneous and disordered aggregation. In the present work, the formation of the hydrated layer on the surface of nanocrystals facilitated the homogeneous and disordered assembly. The crystal phases and the compositions of the nanocrystals were controlled by the tuning of the synthetic conditions, such as the initial pH and metal source concentration. Based on the formation processes and mechanisms, this approach for the coupled synthesis and assembly can be applied to a variety of nanomaterials for preparation of homogeneous but disordered assembly. 相似文献