“禁摩限电”效果综合评价模型

将交通需求级别进行划分后,通过数据包络分析法计算交通需求匹配度和交通运行效率,近乎绝对细化交通运行表现,依据具有时间轴的四维交通状况模拟建立了全新多维度的交通评价体系。此外,利用模糊层次分析法确定道路交通安全评价指标体系中各个指标的权重,同时作出基于差异驱动原理的综合评价。最后,将交通的污染指标提炼为机动车的排放指标和电动车的耗电指标来衡量交通工具对环境的影响。     

Well-Posedness and Asymptotic Behaviors for a Predator-Prey System with Lévy Noise

In this paper, well-posedness and asymptotic behaviors for a predator-prey system with Lévy noise are studied by using stochastic analytical techniques. Firstly, the existence and uniqueness of positive global solution with positive initial value is proved. Then, stochastic permanence for the system is investigated. Finally, persistence in mean and extinction for the system are discussed and some numerical simulations are provided to support our results.     

嵌段共聚物薄膜快速自组装方法

嵌段共聚物 (BCP) 薄膜可通过不同的退火方法诱导其微相分离,从而获得大面积圆柱状、层状和球状等纳米图案。这些长程有序的纳米结构形态,已经广泛应用在纳米光刻和电子器件等多个领域中。目前,有效且快速的退火方法仍然是BCP薄膜自组装技术中的研究热点。本文首先介绍了制备BCP薄膜纳米结构图案常用的退火技术,然后综述了三种新型快速退火技术,最后分析总结了这些退火技术的优缺点。     

Input-to-state stability of impulsive reaction–diffusion neural networks with infinite distributed delays

In this paper, we focus on the global existence–uniqueness and input-to-state stability of the mild solution of impulsive reaction–diffusion neural networks with infinite distributed delays. First, the model of the impulsive reaction–diffusion neural networks with infinite distributed delays is reformulated in terms of an abstract impulsive functional differential equation in Hilbert space and the local existence–uniqueness of the mild solution on impulsive time interval is proven by the Picard sequence and semigroup theory. Then, the diffusion–dependent conditions for the global existence–uniqueness and input-to-state stability are established by the vector Lyapunov function and M-matrix where the infinite distributed delays are handled by a novel vector inequality. It shows that the ISS properties can be retained for the destabilizing impulses if there are no too short intervals between the impulses. Finally, three numerical examples verify the effectiveness of the theoretical results and that the reaction–diffusion benefits the input-to-state stability of the neural-network system.

     

Optimal Harvesting for a Stochastic Predator-prey Model with S-type Distributed Time Delays

In this paper, the optimization problem of harvesting for a stochastic predator-prey model with S-type distributed time delays (which contain both discrete time delays and continuously distributed time delays) is studied by using ergodic method. Sufficient and necessary conditions for the existence of optimal harvesting strategy are obtained. Moreover, the optimal harvesting effort (OHE, for short) and the maximum of expectation of sustainable yield (MESY, for short) are given. Some numerical simulations are introduced to illustrate our main results.     

Optimal harvesting for a stochastic logistic model with S-type distributed time delay

In this paper, the optimization problem of harvesting for a stochastic logistic model with S-type distributed time delay (which contains both discrete time delay and continuously distributed time delay) is studied by using ergodic method.     

Nitrite Electroreduction to Ammonia Promoted by Molecular Carbon Dioxide with Near-unity Faradaic Efficiency

Electrochemical reduction of nitrite (NO₂⁻) offers an energy-efficient route for ammonia (NH₃) synthesis and reduction of the level of nitrite, which is one of the major pollutants in water. However, the near 100 % Faradaic efficiency (FE) has yet to be achieved due to the complicated reduction route with several intermediates. Here, we report that carbon dioxide (CO₂) can enhance the nitrite electroreduction to ammonia on copper nanowire (Cu NW) catalysts. In a broad potential range (−0.7∼−1.3 V vs. RHE), the FE of nitrite to ammonia is close to 100 % with a 3.5-fold increase in activity compared to that obtained without CO_2. In situ Raman spectroscopy and density functional theory (DFT) calculations indicate that CO₂ acts as a catalyst to facilitate the *NO to *N step, which is the rate determining step for ammonia synthesis. The promotion effect of CO₂ can be expanded to electroreduction of other nitro-compounds, such as nitrate to ammonia and nitrobenzene to aniline.     

Ligand-free nickel-catalyzed Kumada couplings of aryl bromides with tert-butyl Grignard reagents

A ligand-free nickel-catalyzed Kumada cross-coupling of aryl bromides and tert-butyl Grignard reagents led to the formation of a series of tert-butyl aryls in moderate to good yields, excellent tBu/iBu ratios, and good functional group compatibility. A radical coupling process is indicated and a mechanism with a Ni(I)-Ni(III) catalytic cycle is proposed.     

One-Pot Direct Oxidation of Primary Amines to Carboxylic Acids through Tandem ortho-Naphthoquinone-Catalyzed and TBHP-Promoted Oxidation Sequence

Biomimetic oxidation of primary amines to carboxylic acids has been developed where the copper-containing amine oxidase (CuAO)-like o-NQ-catalyzed aerobic oxidation was combined with the aldehyde dehydrogenase (ALDH)-like TBHP-mediated imine oxidation protocol. Notably, the current tandem oxidation strategy provides a new mechanistic insight into the imine intermediate and the seemingly simple TBHP-mediated oxidation pathways of imines. The developed metal-free amine oxidation protocol allows the use of molecular oxygen and TBHP, safe forms of oxidant that may appeal to the industrial application.     

Cu添加石榴石磁光薄膜读,写性能的研究

用热分解法在玻璃衬底上制备了Ｃｕ添加的Ｂｉ，Ａｌ：ＤｙＩＧ磁光薄膜，对其静态读、写性能进行了详细的研究。Ｃｕ添加的薄膜可获得高的矫顽力和好的矩形化，对记录畸起着稳定的作用。同时，适量Ｃｕ的添加可起到细化晶粒的作用，对减少晶界噪声有利。