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141.
Da-Liang Zhu Qi Wu Prof. Hai-Yan Li Prof. Dr. Hong-Xi Li Prof. Dr. Jian-Ping Lang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3484-3488
Diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate (HEH) has been utilized as a visible-light photoredox catalyst for the cross coupling of arylhalides and arylsulfinates without transition metal, sacrificial agent, and mediator. This method is compatible with various functional groups and provides diaryl sulfones in good to high yields. Mechanistic studies indicate that this reaction undergoes the stepwise light irradiation of HE−, single electron transfer (SET) in donor–acceptor complex (DAC) from *HE− to arylhalide, trapping of aryl radical with sulfinate, and SET oxidation of sulfone radical anion by HE. to sulfone by the DAC method. 相似文献
142.
The processes of electric ion extraction from plasma induced by pulse lasers are simulated by particle-in-cell(PIC)method and hybrid-PIC method.A new calculation scheme named preprocessing hybrid-PIC is presented because neither of the two methods above is omnipotent,especially under the circumstance of high initial plasma density.The new scheme provides credible results with less computational consumption than PIC method in both one-and two-dimensional simulations,except forΠ-type electrode configuration.The simulation results show that the M-type performs best in all electrode configurations in both high-density and low-density plasma conditions. 相似文献
143.
Xiangdong Liu Hongwei Liu Kexu Yuan Huiping Du 《International Journal of Infrared and Millimeter Waves》1991,12(9):1023-1034
According to the angular-spectrum method, a radiation beam of an antenna horn in the Fresnal region is decomposed into the plane waves with the fast Fourier transform algorithm and the waves diffracted from a reflection grating are superposed as a diffracted beam. Compared with the reflected beam from the same size mirror, the radiation half width of the diffracted beam from a grating is narrower and its lateral shape is shift. These performances have been experimentally verified at Ka-band by: (1). The relative diffraction efficiencies in the first order with two triangular gratings which is put along propagating direction of a beam produced by a conical lens-horn. (2). H-plane lateral width with power—3dB lapsed of the focus beam from a grating and a mirror in a grating spectrometer for millimeter waves (25–100 GHz). 相似文献
144.
This is a continuation of the article (I) with the same title. [Tian-quan Chen, preceding articleJ. Stat. Phys.
25, 491 (1981).] We carry on with the Enskog-Chapman expansion here. 相似文献
145.
Yuan Jian 《Zeitschrift für Physik B Condensed Matter》1992,88(2):141-143
The dc conductivity in the system with a fivefold rotational symmetry in theX-Y plane (QC plane) but having periodicity along theZ direction (C axis) are theoretically investigated from Kubo formula using the recursion method. Numerical results are suggestive of a metallic behavior for the dc conductivity in theQC plane as well as along theC direction, but these two kinds of dc conductivity are anisotropic in magnitude. 相似文献
146.
In this paper, a semidiscrete finite element Galerkin methodfor the equations of motion arising in the 2D Oldroyd modelof viscoelastic fluids with zero forcing function is analysed.Some new a priori bounds for the exact solutions are derivedunder realistically assumed conditions on the data. Moreover,the long-time behaviour of the solution is established. By introducinga StokesVolterra projection, optimal error bounds forthe velocity in the L(L2) as well as in the L(H1)-norms andfor the pressure in the L(L2)-norm are derived which are validuniformly in time t > 0. 相似文献
147.
Yuan Gong Sun 《Applied mathematics and computation》2005,170(2):1095-1103
We prove new oscillation and non-oscillation theorems for the second-order linear difference equation Δ2xn−1 + pnxn = 0, where is a real sequence with pn 0. These results are extensions of earlier results of Zhang and Zhou [Comput. Math. Appl. 39 (2000) 1–7]. 相似文献
148.
Heng-Mei Li Hong-Chun Yuan Hong-Yi Fan 《International Journal of Theoretical Physics》2009,48(10):2849-2864
A class of the single-mode excited GHZ-type entangled coherent states (EGHZECSs) are presented. we exhibit the remarkable
properties of the single-mode EGHZECSs, depended on the excitation photon number, such as entanglement and nonlocality via
investigating their concurrence of entanglement and examining their violation of CHSH inequality. Finally, we propose how
to generate the EGHZECSs by using cavity QED and quantum measurement and by using BBO crystal and single-photon detection
technique, respectively. 相似文献
149.
Wen-Zhong Zhu Qiu-Yue Lin Mei Lu Rui-Ding Hu Xiao-Liang Zheng Jian-Ping Cheng Yun-Yun Wang 《Journal of fluorescence》2009,19(5):857-866
Three novel complexes [Nd(L)(NO3)(H2O)2]·NO3·2H2O (HL1 = N-pyrimidine norcantharidin acylamide acid, C12H13N3O4; HL2 = N-pyridine norcantharidin acylamide acid, C13H14N2O4; HL3 = N-phenyl norcantharidin acylamide acid, C14H15NO4) were synthesized. HL1, HL2 and HL3 are the ligand of complex(1), complex(2) and complex(3), respectively. Their structures were characterized by elemental analysis, conductivity measurement, infrared spectra and
thermogravimetric analysis. The DNA-binding properties of the complexes have been investigated by fluorescence spectroscopy
and viscosity measurements. The results suggest that the complexes can bind to DNA by partial intercalation. The liner Stern-Volmer
quenching constant Ksq values are 3.3(±0.21)(1), 1.7(±0.19)(2) and 0.9(±0.04)(3), respectively. Complex (1) and (2) have been found to cleave pBR322 plasmid DNA at physiological pH and temperature. The test of antiproliferation activity
indicates that complex(1) has strong antiproliferative ability against the SMMC7721 (IC50 = 131.7 ± 23.4 μmol·L−1) and A549 (IC50 = 128.4 ± 19.9 μmol·L−1) cell lines. The inhibition rates of complex(2) (IC50 = 86.3 ± 11.3 μmol·L−1) are much higher than that of NCTD (IC50 = 115.5 ± 9.5 μmol·L−1) and HL2 (111.0 ± 5.7 μmol·L−1) against SMMC7721 cell lines. 相似文献
150.
In this short paper, a bivariate optimal replacement policy for a repairable system with a geometric process maintenance model is discussed. Zhang [Zhang, Y.L., 1994. A bivariate optimal replacement policy for a repairable system. Journal of Applied Probability 31, 1123–1127] and Sheu [Sheu, S.H., 1999. Extended optimal replacement model for deteriorating systems. European Journal of Operational Research 112, 503–516] obtained different expression of the long-run average cost per unit time (i.e. average cost rate) of the system respectively. We show that both of their results are correct, therefore, Sheu’s comment (1999) on the result of Zhang (1994) is wrong. 相似文献