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961.
Encarnación Algaba René van den Brink Chris Dietz 《Journal of Optimization Theory and Applications》2017,172(3):1008-1022
Games under precedence constraints model situations, where players in a cooperative transferable utility game belong to some hierarchical structure, which is represented by an acyclic digraph (partial order). In this paper, we introduce the class of precedence power solutions for games under precedence constraints. These solutions are obtained by allocating the dividends in the game proportional to some power measure for acyclic digraphs. We show that all these solutions satisfy the desirable axiom of irrelevant player independence, which establishes that the payoffs assigned to relevant players are not affected by the presence of irrelevant players. We axiomatize these precedence power solutions using irrelevant player independence and an axiom that uses a digraph power measure. We give special attention to the hierarchical solution, which applies the hierarchical measure. We argue how this solution is related to the known precedence Shapley value, which does not satisfy irrelevant player independence, and thus is not a precedence power solution. We also axiomatize the hierarchical measure as a digraph power measure. 相似文献
962.
Abadie Constraint Qualifications for Convex Constraint Systems and Applications to Calmness Property
In this paper, we mainly study concepts of Abadie constraint qualification and strong Abadie constraint qualification for a convex constraint system defined by a closed convex multifunction and a closed convex subset. These concepts can cover Abadie constraint qualifications for the feasible region of convex optimization problem and the convex multifunction. Several characterizations for these Abadie constraint qualifications are also provided. As applications, we use these Abadie constraint qualifications to characterize calmness properties of the convex constraint system. 相似文献
963.
Andrey Sarantsev 《Journal of Theoretical Probability》2017,30(3):1200-1223
Consider a multidimensional obliquely reflected Brownian motion in the positive orthant, or, more generally, in a convex polyhedral cone. We find sufficient conditions for existence of a stationary distribution and convergence to this distribution at an exponential rate, as time goes to infinity, complementing the results of Dupuis and Williams (Ann Probab 22(2):680–702, 1994) and Atar et al. (Ann Probab 29(2):979–1000, 2001). We also prove that certain exponential moments for this distribution are finite, thus providing a tail estimate for this distribution. Finally, we apply these results to systems of rank-based competing Brownian particles, introduced in Banner et al. (Ann Appl Probab 15(4):2296–2330, 2005). 相似文献
964.
Zhida Chen Yuqing Deng Jiang Bian Lemin Li Guangxian Xu 《Journal of Molecular Structure》1998,434(1-3)
A nonlocal density functional theory (DFT) method has been applied to the calculations on optimized geometry, Mulliken atomic net charges and interatomic Mulliken bond orders as well as total bonding energies (E) in the binary transition metal carbonyl anions with different reduced states [M(CO)n]z− (M=Cr, n=5, 4, 3, z=2, 4, 6; M=Mn, n=5, 4, 3, z=1, 3, 5; M=Fe, n=4, 3, 2, z=2, 4, 6; M=Co, n=4, 3, 2, z=1, 3, 5). For comparison of relative stability, a relative stabilization energy D is defined as D=E([M(CO)n]z−)−nE(CO). The calculated C–O distances are lengthened monotonously with the increase of the anionic charge, but the M–C distances are significantly lengthened only in the higher reduced states. The relative stabilization energy calculated is a considerable negative value in the lower reduced states, but a larger positive value in the higher reduced states. The DFT calculations show that with the increase of the anionic charge, the Mulliken net charges on the M, C, and O atoms all increase, however, an excess of the anionic charge is mainly located at the central metal atom. The calculated C–O Mulliken bond orders decrease consistently with the increase of the anionic charge, but the M–C bond orders exhibit an irregular behavior. However, the total bond orders calculated clearly explain the higher reduced states to be considerably unstable. From analysis of the calculated results, it is deduced that the stability of the binary transition metal carbonyl anions [M(CO)n]z− studied are associated with the coordination number n and the anionic charge z, further, it is possible for the anions studied to be stable if n≥z, conversely, it is impossible when n<z. 相似文献
965.
Fang Liu Wenping Deng Yan Zhang Shenguang Ge Jinghua Yu Mei Yan 《Mikrochimica acta》2014,181(1-2):213-222
We report on a disposable microdevice suitable for sandwich-type electrochemiluminescence (ECL) detection of DNA. The method is making use of CdTe quantum dots functionalized with hierarchical nanoporous PtFe (CdTe@PtFe) nanoparticles and with magnetic graphene nanosheets. The latter were selected as carriers for the capture DNA due to their excellent biomagnetic separation capability and electrical properties. The CdTe@PtFe nanoparticles were used to label the signal DNA which resulted in distinctly enhanced ECL owing to the large specific surface area and good electrical conductivity of the PtFe alloy. A DNA sensor was constructed on a disk-shaped indium tin oxide electrode that was fabricated via etching. Under optimal conditions, the biosensor responds linearly to DNA in the 0.02 fM to 5000 fM concentration range, with a detection limit as low as 15 aM. The electrode is regenerable. The method displays excellent specificity, extremely good sensitivity, and is highly reproducible. Figure
CdTe quantum dots functionalized hierarchical nanoporous PtFe alloy (CdTe@PtFe) and magnetic graphene nanosheet (MGN) were applied for sensitive sandwich-type electrochemiluminescence DNA detection based on a disposable microdevice. The method displays excellent specificity, extremely good sensitivity, and is highly reproducible. 相似文献
966.
Ajay M. Sorty Kamlesh K. Meena Khushboo Choudhary Utkarsh M. Bitla P. S. Minhas K. K. Krishnani 《Applied biochemistry and biotechnology》2016,180(5):872-882
Halotolerant bacteria associated with Psoralea corylifolia L., a luxuriantly growing annual weed in salinity-affected semi-arid regions of western Maharashtra, India were evaluated for their plant growth-promoting activity in wheat. A total of 79 bacteria associated with different parts viz., root, shoot and nodule endophytes, rhizosphere, rhizoplane, and leaf epiphytes, were isolated and grouped based on their habitat. Twelve bacteria isolated for their potential in plant growth promotion were further selected for in vitro studies. Molecular identification showed the presence of the genera Bacillus, Pantoea, Marinobacterium, Acinetobacter, Enterobacter, Pseudomonas, Rhizobium, and Sinorhizobium (LC027447-53; LC027455; LC027457, LC027459, and LC128410). The phylogenetic studies along with carbon source utilization profiles using the Biolog® indicated the presence of novel species and the in planta studies revealed promising results under salinity stress. Whereas the nodule endophytes had minute plant growth-promoting (PGP) activity, the cell free culture filtrates of these strains enhanced seed germination of wheat (Triticum aestivum L). The maximum vigor index was monitored in isolate Y7 (Enterobacter sp strain NIASMVII). Indole acetic acid (IAA) production by the isolates ranged between 0.22 and 25.58 μg mL?1. This signifies the need of exploration of their individual metabolites for developing next-generation bio-inoculants through co-inoculation with other compatible microbes. This study has potential in utilization of the weed-associated microbiome in terms of alleviation of salinity stress in crop plants. 相似文献
967.
A glassy carbon electrode (GCE) modified with polymeric nanocomposite consisting of palladium nanoparticles and a conductive polymeric ionic liquid was prepared. The modified GCE was applied to sensitive and fairly selective electrochemical determination of the mycotoxin zearalenone. Electrocatalytic oxidation is performed in a solution containing 20 % (V/V) acetonitrile and 80 % (V/V) of 1 M perchloric acid. Cyclic voltammetry and square wave voltammetry revealed a well-defined electrocatalytic peak current at overpotential of +0.69 V versus Ag/AgCl. Under optimized experimental conditions, there is a linear relationship between anodic peak current and zearalenone concentration in the range from 0.03 to 35 ng?mL ̄1, and the detection limit is 0.01 ng?mL ̄1. The method was successfully applied to the analysis of zearalenone in spiked food samples and gave recoveries between 95.6 and 104.0 %. 相似文献
968.
Veronika Janíková Eugen Jóna Róbert Janík Viliam Pavlík Darina Ondrušová Michaela Ďurčeková 《Chemical Papers》2016,70(1):131-134
The influence of Ca2+-, Cu2+- and Fe3+-exchanged montmorillonite (MMT) on the type of interaction with aniline in the interlayer space of MMT has been studied by means of X-ray powder diffraction and infrared spectra. Results of X-ray diffraction showed that aniline was successfully intercalated into the interlayer space of MMT. Based on IR spectra evaluation, aniline was indirectly coordinated through a water-bridge in Ca2+- and Fe3+-MMT and it was indirectly coordinated through a water-bridge as well as protonated in Cu2+-MMT (the spectrum of protonated aniline showed deformation and changes in the NH 3 + absorption at approximately 1521 cm?1). It is important to point out that Cu2+-MMT indirect coordination and protonation occur simultaneously. 相似文献
969.
Irena Gancarz Marek Bryjak Joanna Wolska Anna Siekierka Wojciech Kujawski 《Chemical Papers》2016,70(3):350-355
Porous polypropylene membranes were coated with plasma polymerized titanium isopropoxide in a 75 kHz plasma reactor. It was noted that the presence of air in the plasma chamber increased the amount of deposited polymer. Selection of the process parameters enabled obtaining membranes with up to 300 εg cm?2 of polymerized titanium isopropoxide. Deposition of the titanium oxide layer resulted in the reduction of permeate flux but it significantly improved the membrane photocleaning ability. The recovery index reached the level of 95 % for membranes with the highest amount of the titanium oxide deposit. 相似文献
970.
Interface Engineering in Two‐Dimensional Heterostructures: Towards an Advanced Catalyst for Ullmann Couplings 下载免费PDF全文
Dr. Xu Sun Haitao Deng Prof. Wenguang Zhu Zhi Yu Prof. Changzheng Wu Prof. Yi Xie 《Angewandte Chemie (International ed. in English)》2016,55(5):1704-1709
The design of advanced catalysts for organic reactions is of profound significance. During such processes, electrophilicity and nucleophilicity play vital roles in the activation of chemical bonds and ultimately speed up organic reactions. Herein, we demonstrate a new way to regulate the electro‐ and nucleophilicity of catalysts for organic transformations. Interface engineering in two‐dimensional heteronanostructures triggered electron transfer across the interface. The catalyst was thus rendered more electropositive, which led to superior performance in Ullmann reactions. In the presence of the engineered 2D Cu2S/MoS2 heteronanostructure, the coupling of iodobenzene and para‐chlorophenol gave the desired product in 92 % yield under mild conditions (100 °C). Furthermore, the catalyst exhibited excellent stability as well as high recyclability with a yield of 89 % after five cycles. We propose that interface engineering could be widely employed for the development of new catalysts for organic reactions. 相似文献