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101.
Dávid Illés Nagy Alajos Grün Krisztina Lévay Sándor Garadnay István Greiner 《合成通讯》2018,48(6):663-671
The reaction of 1H-imidazol-1-ylacetic acid and two equivalents of phosphorus trichloride/phosphorous acid at 75?°C in sulfolane, or in the presence of catalytic amounts of [bmim][BF4] afforded zoledronic acid in yields up to 75%. The joint use of the ionic liquid additive and sulfolane as the solvent was synergetic affording highly valuable zoledronic acid in a record yield of 93%. 相似文献
102.
《Journal of Energy Chemistry》2014,23(6):684-693
Novel hierarchical porous carbon membranes were fabricated through a simple carbonization procedure of well-defined blending polymer membrane precursors containing the source of carbon polyacrylonitrile (PAN) and an additive of polyvinylpyrrolidone (PVP), which was prepared using phase inversion method. The as-fabricated materials were further used as the active electrode materials for supercapacitors. The effects of PVP concentration in the casting solution on structure feature and electrochemical capacitive performance of the as-prepared carbon membranes were also studied in detail. As the electrode material for supercapacitor, a high specific capacitance of 278.0 F/g could be attained at a current of 5 mA/cm2 and about 92.90% capacity retention could be maintained after 2000 charge/discharge cycles in 2 mol/L KOH solution with a PVP concentration of 0.3 wt% in the casting solution. The facile hierarchical pore structure preparation method and the good electrochemical capacitive performance make the prepared carbon membrane particularly promising for use in supercapacitor. 相似文献
103.
Reza Torabi 《Physica B: Condensed Matter》2012,407(12):2109-2111
The effect of noise on the Dirac phase of electron in the presence of screw dislocation is studied. An uncorrelated noise, which coincides with the nature of thermal fluctuations, is adopted. Results indicate that the Dirac phase is robust against the existing noise in the system. 相似文献
104.
R. Kumar E. BarriosA. MacRae E. CairnsE.H. Huntington A.I. Lvovsky 《Optics Communications》2012,285(24):5259-5267
We present a comprehensive theory and an easy to follow method for the design and construction of a wideband homodyne detector for time-domain quantum measurements. We show how one can evaluate the performance of a detector in a specific time-domain experiment based on the electronic spectral characteristic of that detector. We then present and characterize a high-performance detector constructed using inexpensive, commercially available components such as low-noise high-speed operational amplifiers and high-bandwidth photodiodes. Our detector shows linear behavior up to a level of over 13 dB clearance between shot noise and electronic noise, in the range from DC to 100 MHz. The detector can be used for measuring quantum optical field quadratures both in the continuous-wave and pulsed regimes with standard commercial mode-locked lasers. 相似文献
105.
106.
《Physics letters. A》2014,378(38-39):2831-2844
A new global stochastic search, guided mainly through derivative-free directional information computable from the sample statistical moments of the design variables within a Monte Carlo setup, is proposed. The search is aided by imparting to the directional update term additional layers of random perturbations referred to as ‘coalescence’ and ‘scrambling’. A selection step, constituting yet another avenue for random perturbation, completes the global search. The direction-driven nature of the search is manifest in the local extremization and coalescence components, which are posed as martingale problems that yield gain-like update terms upon discretization. As anticipated and numerically demonstrated, to a limited extent, against the problem of parameter recovery given the chaotic response histories of a couple of nonlinear oscillators, the proposed method appears to offer a more rational, more accurate and faster alternative to most available evolutionary schemes, prominently the particle swarm optimization. 相似文献
107.
Johannes Kraus Maria Lymbery Svetozar Margenov 《Numerical Linear Algebra with Applications》2014,21(3):375-398
This paper discusses a class of multilevel preconditioners based on approximate block factorization for conforming finite element methods employing quadratic trial and test functions. The main focus is on diffusion problems governed by a scalar elliptic partial differential equation with a strongly anisotropic coefficient tensor. The proposed method provides a high robustness with respect to non‐grid‐aligned anisotropy, which is achieved by the interaction of the following components: (i) an additive Schur complement approximation to construct the coarse‐grid operator; (ii) a global block (Jacobi or Gauss–Seidel) smoother complementing the coarse‐grid correction based on (i); and (iii) utilization of an augmented coarse grid, which enhances the efficiency of the interplay between (i) and (ii). The performed analysis indicates the high robustness of the resulting two‐level method. Moreover, numerical tests with a nonlinear algebraic multilevel iteration method demonstrate that the presented two‐level method can be applied successfully in the recursive construction of uniform multilevel preconditioners of optimal or nearly optimal order of computational complexity. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
108.
Weihua Zhou Zoukangning Yu Ming Zhang Lifu Zhang Jingping Yin Qingyun Ai Liqiang Huang Feng Liu Jianrong Zeng Yiwang Chen 《Journal of Polymer Science.Polymer Physics》2019,57(14):941-951
In order to explore the role of fluorine atoms on photostability as well as morphology control of active layer in the presence of 1,4‐butanedithiol (BT), the four polymers with or without fluorine atoms in the backbones including polythieno[3,4‐b]thiophene/benzodithiophene, poly[(4,8‐bis‐(2‐ethylhexyloxy)‐benzo(1,2‐b:4,5‐b9)dithiophene)‐2,6‐diyl‐alt‐(4‐(2‐ethylhexanoyl)‐thieno[3,4‐b]thiophene‐)‐2‐6‐diyl)], poly[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b;4,5‐b′]dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b]thiophene‐)‐2‐carboxylate‐2‐6‐diyl)], and poly[4,8‐bis‐(2‐ethyl‐hexyl‐thiophene‐5‐yl)‐benzo[1,2‐b:4,5‐b0]dithiophene‐2,6‐diyl]‐alt‐[2‐(20‐ethyl‐hexanoyl)‐thieno [3,4‐b]thiophen‐4,6‐diyl] were selected for comparison. It is found that the specimens containing fluorine atoms in polymer backbones showed of higher stability after illumination for 1 h in the presence of BT additive, contributing to the higher domain purity. The specific interaction between fluorine atoms and thiol groups was demonstrated by the appearance of novel absorption peak at 2663.1 cm?1, in addition to the broadening of peak at 2556.2 cm?1 ascribing to S? H stretching vibration as confirmed by Fourier transform infrared (FTIR) spectroscopy. The finding may guide the accurate use of thiols as effective solvent additive in morphology and stability optimization. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 941–951 相似文献
109.
Mayuribala Mangrulkar Sergey Yu. Luchkin Aleksandra G. Boldyreva Pavel A. Troshin Keith J. Stevenson 《Mendeleev Communications》2021,31(3):319-322
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110.