Structure and cooperativity of the hydrogen bonds in sodium dihydrogen triacetate

Geometry and energetics of low energy conformers of sodium dihydrogen triacetate (SDHTA) and its anion are studied using density functional theory (DFT) at the Becke, Lee‐Yang‐Parr hybrid functional (BLYP) and Becke, three‐parameter, Lee‐Yang‐Parr hybrid functional (B3LYP) levels. For both cases, two structures of comparable energy are found, which have different symmetry with respect to the two hydrogen bonds (HBs). DFT‐based Born–Oppenheimer molecular dynamics simulations are performed for SDHTA, which show that both structures are visited at room temperature conditions. The trajectory analysis further reveals that the two HBs behave anticooperative, that is, on average elongation of one HB is accompanied by a compression of the other one. This is in accord with nuclear magnetic resonance (NMR) experimental studies for a similar counter ion–dihydrogen triacetate complex. © 2012 Wiley Periodicals, Inc.     

Analysis of cooperative and competitive spectrum sharing for heterogeneous networks based on differential dynamics model

The heterogeneous networks belonging to different service providers form a coalition system for maximizing the profit, where they may either compete or cooperate with each other. In this paper, we introduce the Lokta–Volterra model, a differential dynamics model, to build the competitive and cooperative mechanisms of heterogeneous networks. It considers the natural growth rate of the network itself and competitive and cooperative effects among networks. Then, according to the ordinary differential principle, the stability of the proposed model and its equilibrium points are analyzed. And finally, system performances are evaluated by Vensim that is used for developing, analyzing, and packaging dynamic feedback models. Analysis and simulation results show that the natural growth rate of the network cannot increase its profit, but effective cooperative mechanism among heterogeneous networks can increase the profit of each network. Copyright © 2013 John Wiley & Sons, Ltd.     

Risk and Intellectual Property in Technical Standard Competition： A Game Theory Perspective

Technical standard is typically characterized by network effect.The key point for a technical standard is the consumers＇ choice,which is based on consumers＇ maximum benefits.When a technical standard becomes a national standard,its interests have been integrated into the national interests.National interests are divided into economic profits and security factors.From the perspective of consumers＇ choice,this paper deals with the main factors which affect the result of technical standard competition- the risk and profits of intellectual property based on the assumption of bounded rationality and dynamic game theory.     

Co (II)‐C12 alkyl carbon chain multi‐functional ionic liquid immobilized on nano‐SiO2 nano‐SiO2@CoCl3‐C12IL as an efficient cooperative catalyst for C–H activation by direct acylation of aryl halides with aldehydes

Nano‐silica supported ionic liquids composed of alkyl carbon chain and transition metal chlorides anions have been prepared and successfully applied as a heterogeneous catalyst in the direct aldehyde C‐H activation. Catalytic results indicated that nano‐SiO₂ supported ionic liquid consisting C12 alkyl carbon chain and CoCl₃ anion nano‐SiO₂@CoCl₃‐C12IL showed excellent catalytic properties with good to excellent yields towards the desired aryl ketones. The excellent recyclability of the supported catalyst, mild reaction conditions, low catalyst loading, and operational simplicity are the important features of this methodology.     

基于Unity 3D的第三人称摄像机被遮挡的处理

针对涉及第三人称视角游戏中,因摄像机和游戏主角之间存在一定的距离,容易出现障碍物遮挡,会影响用户体验的情况.可采用射线方法来探测障碍物,并在出现遮挡时将遮挡障碍物做透明化处理.