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961.
Chang H Cheng J Liu X Gao J Li M Li J Tao X Ding F Zheng Z 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(32):8896-8903
The bandgap opening of graphene is extremely important for the expansion of the applications of graphene-based materials into optoelectronics and photonics. Current methods to open the bandgap of graphene have intrinsic drawbacks including small bandgap openings, the use hazardous/harsh chemical oxidations, and the requirement of expensive chemical-vapor deposition technologies. Herein, an eco-friendly, highly effective, low-cost, and highly scalable synthetic approach is reported for synthesizing wide-bandgap fluorinated graphene (F-graphene or or fluorographene) semiconductors under ambient conditions. In this synthesis, ionic liquids are used as the only chemical to exfoliate commercially available fluorinated graphite into single and few-layer F-graphene. Experimental and theoretical results show that the bandgap of F-graphene is largely dependent on the F coverage and configuration, and thereby can be tuned over a very wide range. 相似文献
962.
Influence of reduction energy match among CuO species in CuO-CeO2 catalysts on the catalytic performance for CO preferential oxidation in excess hydrogen 下载免费PDF全文
In the present study, we have investigated the reducibility of CuO species on CuO-CeO2 catalysts and the influence of CuO species on the catalytic performance for CO preferential oxidation (CO PROX) in excess hydrogen. It is revealed that the smaller the difference of reduction temperature (denoted as ?T) for two adjacent CuO species is, the higher the catalytic activity of CuO-CeO2 for the PROX in excess hydrogen may be obtained. It means that if the reduction energy of Cu0-Cu2+ pairs matched better, the reduction-oxidation recycle of Cu0-Cu2+ pairs would go on more easily, then the transferring energy of Cu0-Cu2+ pairs would be lesser. Therefore, the CuO-CeO2 catalysts will be largely improved in their catalytic performance if the different CuO species on the catalysts have matched the reduction energy, which would allows them to cooperate effectively. 相似文献
963.
Min Li Li-Zhi Liao Xiaoming Yuan 《Journal of Optimization Theory and Applications》2013,159(2):412-436
In the literature, it was shown recently that the Douglas–Rachford alternating direction method of multipliers can be combined with the logarithmic-quadratic proximal regularization for solving a class of variational inequalities with separable structures. This paper studies the inexact version of this combination, where the resulting subproblems are allowed to be solved approximately subject to different inexactness criteria. We prove the global convergence and establish worst-case convergence rates for the derived inexact algorithms. 相似文献
964.
The globally uniquely solvable (GUS) property of the linear transformation of the linear complementarity problems over symmetric cones has been studied recently by Gowda et al. via the approach of Euclidean Jordan algebra. In this paper, we contribute a new approach to characterizing the GUS property of the linear transformation of the second-order cone linear complementarity problems (SOCLCP) via some basic linear algebra properties of the involved matrix of SOCLCP. Some more concrete and checkable sufficient and necessary conditions for the GUS property are thus derived. 相似文献
965.
通过无机碘盐(MIn)与 cis-[Fe(CO)4I2]反应制备了 5 个盐类化合物 fac-M[Fe(CO)3I3]n (Mn+=Na+ (1),K+ (2),Mg2+ (3),Ca2+ (4),NH4+ (5)),探讨了阳离子Mn+对fac-[Fe(CO)3I3]-阴离子的稳定性和细胞毒性的影响。通过傅里叶变换红外光谱(FTIR)监测,发现盐 1~5在 DMSO、D2O、生理盐水等介质中均能缓释 CO,其释放动力学符合一级反应动力学模型;还发现溶液中碘离子的浓度和酸度对该阴离子的缓释CO性能也具有调节作用。通过噻唑蓝(MTT)实验评估了盐1~5对膀胱癌细胞的毒性,其24 h半抑制浓度(IC50)在 25~43 μmol·L-1。与有机铵阳离子类的盐化合物相比,盐1~5在含水介质中的释放 CO速率下降,毒性亦有下调。研究还发现这类fac-[Fe(CO)3I3]-阴离子在缓释CO的同时释放碘自由基,并能导致线粒体活性氧(ROS)水平、Parkin蛋白表达均上调。铁死亡抑制剂(Ferrostatin-1和Liproxstatin-1)试验结果表明这类化合物可能引发铁死亡通路并促进肿瘤细胞死亡。 相似文献
966.
Pyng Yu Xiaoming Wen Yon‐Rui Toh Jane Huang Jau Tang 《Particle & Particle Systems Characterization》2013,30(5):467-472
The metallophilic bond is a weak interaction between closed‐shell ions and has been widely used a probe for various sensing of toxic chemicals for environmental safety concerns. Here, the interaction between Au nanoclusters (NCs) and metallic ions (mercury (Hg2+) and copper (Cu2+) ions) is explored using steady‐state and time‐resolved luminescence and transient absorption measurements. For Hg2+ ions, the delayed fluorescence (DF) of bovine serum albumin (BSA) protected Au25 (Au25@BSA) NCs is quenched via an effective triplet state electron transfer through the metallophilic bond. However, the Cu2+ ions do not alter the DF in Au25@BSA NCs because of the absence of the metallophilic interaction. Furthermore, for Au8@BSA and Au10@histidine, in which there are no Au+ ions on the surface, the fluorescence is not quenched by Hg2+ ions. Such a novel triplet electron transfer process through metallophilic bonds are observed and reported for the first time. The reduction of the reverse intersystem crossing is the crucial for Hg2+ ion sensing in the fluorescent Au25@BSA NCs. 相似文献
967.
968.
A new kind of generalized heterochronous synchronization phenomenon is reported. Different kinds of generalized synchronous states (including generalized anticipated, isochronous and lag projective synchronization) coexist among different state variables between two unidirectionally coupled time-delayed chaotic systems. The analytical conditions for generalized heterochronous synchronization are obtained. We also find that the synchronization conditions are independent of the delay times in the original time-delayed system. The theoretical results are well confirmed by the numerical simulations and electronic circuit experiments. 相似文献
969.
In this paper, the issue on impulsive control and synchronization of nonlinear system with impulse time window are investigated. The considered impulsive effects can be stochastically occurred at a determined time window. Hence, the impulses here can be more general and more applicable than the fixed impulses. Some novel and easy-to-check criteria with impulse time window are obtained to guarantee the impulsive control and synchronization global asymptotical stable. Especially, on the basis of the our analysis, we only choose an efficient impulse time window instead of choosing fixed-impulse sequences. Finally, the simulation results further demonstrate the effectiveness of our theoretical results. 相似文献
970.
Hao Li Yuyu Zhang Xiaoming Wang Zhengnan Yin Heng Xiao 《Acta Mechanica Solida Sinica》2014,27(5):441-453
An explicit, exact approach is proposed to obtain multi-axial elastic potentials for isotropic rubber-like materials undergoing large incompressible deformations. By means of two direct, explicit procedures, this approach reduces the problem of determining multi-axial poten- tials to that of determining one-dimensional elastic potentials. To this end, two one-dimensional potentials for uniaxial case and simple shear case are respectively determined via spline inter- polation and, then, the two potentials are extended to generate a multi-axial elastic potential using a novel method based on certain logarithmic invariants. Eventually, each of the multi-axial potentials will exactly match the finite strain data from four benchmark tests. 相似文献