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91.
Ding Wenwen He Yongjia Lu Linnu Rao Meijuan Wang Fazhou 《Journal of Thermal Analysis and Calorimetry》2019,135(4):2009-2018
Journal of Thermal Analysis and Calorimetry - The present task is to investigate the influence of iron on the mineral composition and microstructure of the phase Q (C20A13M3S3, in the text below... 相似文献
92.
Bijun Gao Jin Zhou Hongliang Wang Guping Zhang Jinghui He Qingfeng Xu Najun Li Dongyun Chen Hua Li Jianmei Lu 《中国化学》2019,37(2):148-154
Tetracycline (TC) and other antibiotics accumulated in groundwater and soil pollute ecological environment and threaten human health. Gold nanoparticles doped on photocatalysts are able to enhance the photodegradation efficiency during removing these antibiotics, but preparation of Au nanoparticles of well‐dispersion on photocatalysts remains challenging. In this work, zeolite imidazolate (ZIF‐8) was employed as the precursor to prepare Au@ZnO photocatalyst via impregnation and in‐situ reduction method to efficiently degrade the tetracycline in the aqueous solution. Au nanoparticles are of 10 nm in size and uniformly dispersed on the surfaces of ZnO microstructures. The as‐prepared Au@ZnO is able to remove 85.5% of TC of 0.010 mg/mL within 2 h, presenting higher photocatalytic activity than pure ZnO catalyst. Most importantly, the catalyst shows its superior stability after five cycles without structure and activity changing. The mechanism of the photocatalytic degradation was discussed in detail. 相似文献
93.
Viscous Shock Wave to an Inflow Problem for Compressible Viscous Gas with Large Density Oscillations
Acta Mathematicae Applicatae Sinica, English Series - This paper is concerned with the inflow problem for one-dimensional compressible Navier-Stokes equations. For such a problem, Huang, Matsumura,... 相似文献
94.
Let E?R be an interval. By studying an admissible family of branching mechanisms{ψt,t ∈E} introduced in Li [Ann. Probab., 42, 41-79(2014)], we construct a decreasing Levy-CRT-valued process {Tt, t ∈ E} by pruning Lévy trees accordingly such that for each t ∈E, Tt is a ψt-Lévy tree. We also obtain an analogous process {Tt*,t ∈E} by pruning a critical Levy tree conditioned to be infinite. Under a regular condition on the admissible family of branching mechanisms, we show that the law of {Tt,t ∈E} at the ascension time A := inf{t ∈E;Tt is finite} can be represented by{Tt*,t∈E}.The results generalize those studied in Abraham and Delmas [Ann. Probab., 40, 1167-1211(2012)]. 相似文献
95.
Characterizations of ( m,n )-Jordan Derivations and ( m,n )-Jordan Derivable Mappings on Some Algebras 下载免费PDF全文
Let R be a ring, M be a R-bimodule and m, n be two fixed nonnegative integers with m + n = 0. An additive mapping δ from R into M is called an(m, n)-Jordan derivation if(m +n)δ(A~2) = 2 mAδ(A) + 2nδ(A)A for every A in R. In this paper, we prove that every(m, n)-Jordan derivation with m = n from a C*-algebra into its Banach bimodule is zero. An additive mappingδ from R into M is called a(m, n)-Jordan derivable mapping at W in R if(m + n)δ(AB + BA) =2mδ(A)B + 2 mδ(B)A + 2 nAδ(B) + 2 nBδ(A) for each A and B in R with AB = BA = W. We prove that if M is a unital A-bimodule with a left(right) separating set generated algebraically by all idempotents in A, then every(m, n)-Jordan derivable mapping at zero from A into M is identical with zero. We also show that if A and B are two unital algebras, M is a faithful unital(A, B)-bimodule and U = [A M N B] is a generalized matrix algebra, then every(m, n)-Jordan derivable mapping at zero from U into itself is equal to zero. 相似文献
96.
97.
Xin Cheng Dr. Zi-Yu Li Li-Hui Mou Yi Ren Dr. Qing-Yu Liu Prof. Dr. Xun-Lei Ding Prof. Dr. Sheng-Gui He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16523-16527
The side-on-end-on coordination of N2 can be very important to activate and functionalize this very stable molecule. However, such coordination has rarely been reported. This study reports a gas-phase species (a polynuclear vanadium nitride cluster anion [V5N5]−) that can capture N2 efficiently (12 %), and the quantum chemistry modelling suggests an unusual side-on-end-on coordination. The cluster anions were generated by laser ablation and the reaction with N2 has been characterized by mass spectrometry, photoelectron imaging spectroscopy, and density functional theory calculations. The back-donation interactions between the localized d–d bonding orbitals on the low-coordinated dual metal (V) sites and the antibonding π* orbitals of N2 are the driving forces to adsorb N2 with a high binding energy (about 2.0 eV). 相似文献
98.
Li Song Jiaxiang Lin Yang He Jingqing Li Jing Sheng Shichun Jiang Dinghai Huang 《Journal of Polymer Science.Polymer Physics》2019,57(3):142-151
Time‐dependent demixing enthalpy recovery behavior of aqueous poly(vinyl methyl ether) (PVME) solutions exhibits distinct recovery characteristics in three concentration regions. The absence of recovery behavior below a water concentration of 38.3 wt % indicates that the PVME coil is in a globular state. The typically sigmoidal recovery behavior of demixing enthalpy above 38.3 wt % is ascribed to the reswelling of the collapsed polymer coils induced by the entropic effect. The increase in difference between the upper and lower limits indicates the continued swelling of the PVME coils. Above 65 wt %, a dominant diluting effect can be observed, and a much longer phase separation time is needed to reach the expected lower limit. In contrast, the recovery of demixing enthalpy in a wide range of water concentration (from 38.3 to 90 wt %) exhibits the same feature. The infrared spectroscopy results are in agreement with the above macroscopic differential scanning calorimetry results. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 142–151 相似文献
99.
Wen‐ming He 《Numerical Methods for Partial Differential Equations》2019,35(6):2044-2055
In this article, we will discuss the local ultraconvergence of high‐degree finite element method based on a rectangular partition for the second‐degree elliptic problem with constant coefficients in Ω ? ?2 , u( y ) = 0 on ?Ω . Based on suitable regularity, ultraconvergence of the displacement of the extrapolated kth (k ≥ 3) degree finite element solution has been obtained by an extrapolation technique. Finally, numerical experiments are applied to demonstrate our theoretical findings. 相似文献
100.
Numerical Algorithms - Studying the dynamics of runaway electrons has theoretical and practical significance. As the system is highly relativistic, multi-scale and nonlinear, accurate and efficient... 相似文献