摘要：使用液态碳氢化合物燃料的固体氧化物燃料电池(SOFCs)的商业化极大地受到阳极易积碳的阻碍.调控碳氢燃料重整反应位点的局域蒸汽/碳比以提高抗积碳性能是有效的,但仍面临挑战.本文报道了一种新型二氧化铈基催化剂(Ce_(0.95)Ru_(0.05)O_(2-δ),CR5O)的理性设计.催化剂在实际应用过程中,表现出优异的抗积碳性能.在电池运行条件下,催化剂CR5O被还原为二氧化铈骨架及镶嵌在骨架表面的Ru纳米颗粒(Ru/Ce_(0.95)Ru_(0.05)O_(2)-δ,Ru/CR5-xO).Ru/CR5-xO表现出优异的自水合能力,可以有效去除催化剂表面产生的积碳.当应用于以液态碳氢化合物为燃料的SOFCs时,电池表现出优异的电化学性能:在750℃下,以甲醇为燃料时,电池的峰值功率密度达到1.010W cm^(-2),并且在稳定运行的200h以内,没有明显积碳现象.此外,密度泛函理论计算表明,Ru/CR5-xO催化剂修饰的Ni-YSZ阳极的高活性和抗积碳性能归因于速率限制步骤的能垒降低和用于快速除碳的COH中间体的形成.

摘要：Darcy's law only applying to the flow domain is extended to the entire fracture network domain including the dry *** partial differential equation(PDE) formulation for unconfined seepage flow problems for discrete fracture network is established,in which a boundary condition of Signorini's type is prescribed over the potential seepage *** order to reduce the difficulty in selecting trial functions,a new variational inequality formulation is presented and mathematically proved to be equivalent to the PDE *** numerical procedure based on the VI formulation is proposed and the corresponding algorithm has been *** a continuous penalized Heaviside function is introduced to replace a jump function in finite element analysis,oscillation of numerical integration for facture elements cut by the free surface is eliminated and stability of numerical solution is *** numerical results from two typical examples demonstrate,on the one hand the effectiveness and robustness of the proposed method,and on the other hand the capability of predicting main seepage pathways in fractured rocks and flow rates out of the drainage system,which is very important for performance assessments and design optimization of complex drainage system.

摘要：电化学二氧化碳还原反应(CO_(2)RR)通过将CO_(2)转化为高价值化学品和燃料来降低其在大气中的浓度,是解决能源危机的重要途径.因此,合理设计高效、经济的电化学催化剂至关重要.研究发现,铜(Cu)是一种性能优越的金属催化剂,可将CO_(2)还原成碳氢化合物和醇类,尤其是C_(2+)产物.然而,Cu催化剂也存在一定问题(如过电位高和CO_(2)RR选择性差等),从而限制了其应用.近年来,单原子催化剂(SACs)因其具有高活性、高选择性和高稳定性,已成为异相催化剂领域的新兴研究前沿.本文总结了CO_(2)RR的各种铜基SACs的最新研究进展,尤其是活性位点与关键反应中间产物相互作用的调控策略.这种相互作用对于设计活性位点以及优化多电子还原步骤和提高催化性能非常重要.同时,本文还讨论了金属中心调控、铜基单原子合金催化剂、非金属SACs、串联催化剂和复合催化剂等研究前沿.最后,总结了SACs应用于CO_(2)RR的挑战与展望.

摘要：According to the actual engineering problem that the precise load model of shield machine is difficult to achieve,a design method of sliding mode robust controller oriented to the automatic rectification of shield machine was proposed. Firstly,the nominal load model of shield machine and the ranges of model parameters were obtained by the soil mechanics parameters of certain geological conditions and the messages of the self-learning of shield machine by tunneling for previous segments. Based on this rectification mechanism model with known ranges of parameters,a sliding mode robust controller was proposed. Finally,the simulation analysis was developed to verify the effectiveness of the proposed controller. The simulation results show that the sliding mode robust controller can be implemented in the attitude rectification process of the shield machine and it has stronger robustness to overcome the soil disturbance.

摘要：这份报纸学习样品数据的问题为有变化时间的延期的不明确的连续时间的模糊大规模系统的可靠 H 夸张控制。第一，模糊夸张模型( FHM )被用来为某些复杂大规模系统建立模型，然后根据 Lyapunov 指导方法和大规模系统的分散的控制理论，线性 matrixine 质量( LMI )基于条件 arederived toguarantee H 性能不仅当所有控制部件正在操作很好时，而且面对一些可能的致动器失败。而且，致动器的精确失败参数没被要求，并且要求仅仅是失败参数的更低、上面的界限。条件依赖于时间延期的上面的界限，并且不依赖于变化时间的延期的衍生物。因此，获得的结果是不太保守的。最后，二个例子被提供说明设计过程和它的有效性。

摘要：We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart *** method is based on generalized natural frequency and takes hydraulic oil into consideration.A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass *** the model,the effect of leg inertia and the influence of design parameters on the generalized natural frequency are ***,numerical examples are presented to validate and confirm the efficiency of the mathematical *** results show that the leg inertia,especially the piston part plays an important role in the *** optimum diameter ratio of the base to the moving platform is between 2 and 3,and the optimum joint angle ratio of the base to the moving platform is about *** smaller joint angles and a longer leg stroke are favorable for raising system *** system oil should be preprocessed for large platforms with a requirement for good dynamic performance.

摘要：Recent emergence of diverse services have led to explosive traffic growth in cellular data networks. Understanding the service dynamics in large cellular networks is important for network design, trouble shooting, quality of service(Qo E) support, and resource allocation. In this paper, we present our study to reveal the distributions and temporal patterns of different services in cellular data network from two different perspectives, namely service request times and service duration. Our study is based on big traffic data, which is parsed to readable records by our Hadoop-based packet parsing platform, captured over a week-long period from a tier-1 mobile operator's network in china. We propose a Zipf's ranked model to characterize the distributions of traffic volume, packet, request times and duration of cellular services. Two-stage method(Self-Organizing Map combined with kmeans) is first used to cluster time series of service into four request patterns and three duration patterns. These seven patterns are combined together to better understand the fine-grained temporal patterns of service in cellular network. Results of our distribution models and temporal patterns present cellular network operators with a better understanding of the request and duration characteristics of service, which of great importance in network design, service generation and resource allocation.

摘要：In this work, a 90-nm critical dimension （CD） technological process in an ArF laser lithography system is simulated, and the swing curves of the CD linewidth changing with photoresist thickness are obtained in the absence and presence of bottom antireflection coating （BARC）. By analysing the simulation result, it can be found that in the absence of BARC the CD swing curve effect is much bigger than that in the presence of BARC. So, the BARC should be needed for the 90-nm CD manufacture. The optimum resist thickness for 90-nm CD in the presence of BARC is obtained, and the optimizing process in this work can be used for reference in practice.

摘要：We propose an effective method to design the working parameters of a pulse-driven charge qubit implemented with double quantum *** is shown that intrinsic qubit population leakage to undesired states in the control and measurement process can be determined by the simulation of coherent dynamics of the qubit and minimized by choosing proper working parameters such as pulse *** result demonstrated here bodes well for future quantum gate operations and quantum computing applications.

摘要：粒子图象 velocimetry 技术被用来分析后面的旋涡并且阐明他们与在 0.48 m 直径的一辆搅动的坦克的骚乱性质的关系，由四台不同磁盘汽轮机，包括的 Rushton 汽轮机， concaved 片磁盘汽轮机，半椭圆的片磁盘汽轮机，和寓言的片鼓动了磁盘汽轮机。impeller 片附近的平均阶段、解决阶段的流动领域被测量，后面的旋涡的结构详细被学习。旋涡的地点，尺寸和力量被简化 2 标准决定，结果证明片形状在后面的旋涡特征上有大效果。更大的弯曲在 impeller 尖端，在上面、更低的旋涡之间的更大的距离和更长的旋涡生活导致了旋涡的更长的住处时间，也导致更小、更强壮的旋涡。另外，在分泌物流动的狂暴的动能和狂暴的精力驱散坚定、讨论。高狂暴的动能和狂暴的精力驱散区域在上面、更低的旋涡之间被定位并且与他们一起移动了。尽管限制了挑选阶段流动，介绍结果为有圆盘汽轮机的搅动的坦克的可靠设计和按比例增加是必要的。