摘要：Large-scale production of polyethylene in industry requires efficient elimination of the trace amount of acetylene ***,zeolite adsorption or the conversion of acetylene to ethylene via selective semi-hydrogenation on Pd catalysts is the commonly used *** this work,we investigate the reaction mechanisms of acetylene hydrogenation on defective graphene(DG)supported singleatom catalysts(SACs),M1/SV-G and M1/DV-G(M=Ni,Pd and Pt)using density functional theory(DFT),where SV-G and DV-G represent DG with single and double vacancies,*** is shown that the metal single-atoms(SAs)as well as their different coordination numbers both affect the activity and selectivity of the hydrogenation process.M1/DV-G provides better H2 dissociation ability than M1/SV-G,which accounts for the poor acetylene hydrogenation activity of M1/*** on the reaction barriers,Pt1/DV-G and Ni1/DV-G are better catalysts than other systems considered here,with Ni1/DV-G exhibiting high selectivity for the semi-hydrogenation product of *** results provide insights for the design of highly selective and noble-metal-free SACs for acetylene hydrogenation on carbon materials.

摘要：Recently service orientation is becoming a mainstream approach for building large scale software systems. A key requirement in service-oriented design is the dependability of service. It stipulates that the behavior of services is controllable. Formal models can aid in constructing software in a dependable manner. They can describe ser- vices precisely and compose them together consistently. This paper presents a strategy for service realization based on a novel layered formal model. When a service is provided or required via internet, the semantic consistency becomes critical issue, Our architecture tackles the issue by proposing a novel scheme： defining contract of a service to keep semantic information. Although service-oriented design is our prime target, the contract models, to a large extent, are independent of the framework of design and therefore applicable to large scale software design in general.

摘要：We introduce PBGFs with the cladding made of our newly designed quasi-hexagonal air holes and demonstrate how it actually operates. This cladding structure is introduced for the first time to the best of our knowledge, and is realized by making use of the hydrofluoric acid＇s corrosive properties. The fibre corrosion can be accurately controlled, thus opening us the gate for the design and fabrication of new PB. GFs with more complex and more efficient cladding structures. Numerical results and actual simulations indicate that PBGFs built with this cladding structure have improved b^dgap properties and guiding bands as wide as 500 nm have been theoretically reached. Using the same method, we have also been able to design two other types of PBGFs with improved cladding structure.

摘要：For the surgical treatment of cardiovascular disease(CVD),there is a clear and unmet need in developing small-diameter(diameter<6 mm)vascular *** our previous work,sulfated silk fibroin(SF)was successfully fabricated as a potential candidate for preparing vascular grafts due to the great cytocompatibility and ***,vascular graft with single layer is difficult to adapt to the complex internal *** this work,polycaprolactone(PCL)and sulfated SF were used to fabricate bilayer vascular graft(BLVG)to mimic the structure of natural blood *** enhance the biological activity of BLVG,nicorandil(NIC),an FDA-approved drug with multi-bioactivity,was loaded in the BLVG to fabricate NIC-loaded *** morphology,chemical composition and mechanical properties of NIC-loaded BLVG were *** results showed that the bilayer structure of NIC-loaded BLVG endowed the graft with a biphasic drug release *** in vitro studies indicated that NIC-loaded BLVG could significantly increase the proliferation,migration and antioxidation capability of endothelial cells(ECs).Moreover,we found that the potential biological mechanism was the activation of PI3K/AKT/eNOS signaling ***,the results effectively demonstrated that NIC-loaded BLVG had a promising in vitro performance as a functional small-diameter vascular graft.

摘要：This paper studies the consensus problem of multi-agent systems in which all agents are modeled by a general linear system. The authors consider the case where only the relative output feedback between the neighboring agents can be measured. To solve the consensus problem, the authors first construct a static relative output feedback control under some mild constraints on the system model. Then the authors use an observer based approach to design a dynamic relative output feedback control. If the adjacent graph of the system is undirected and connected or directed with a spanning tree, with the proposed control laws, the consensus can be achieved. The authors note that with the observer based approach, some information exchange between the agents is needed unless the associated adjacent graph is completely connected.

摘要：本文研究了具有扇形执行器的多机电力系统气门开度的时滞无关分散控制器和鲁棒分散控制器的设计问题.首先利用三角变换把非线性关联函数变换为子系统状态变量的二次有界不等式形式,然后基于Lyapunov稳定性理论,推导出闭环多机电力系统及其参数不确定系统渐近稳定的线性矩阵不等式(LMI)充分条件,最后以两机无穷大母线系统为例进行了仿真分析,验证了所提方法的有效性.

摘要：This paper aims to investigate the effectiveness of rubric-referenced student self-assessment(SSA)on students’English essay writing by employing a two-group pre-post-quasi-experimental research *** method was tested on 54 students at a Chinese *** a 17-week experiment,the experimental group(EG)received the rubric and annotated samples,while the comparison group(CG)received only the rubric in *** sources included students’scores in the pre-test and post-test and *** findings indicated that the EG made significantly stronger progress than the CG in the *** results suggested that annotation-based rubric-referenced SSA can help students understand the task requirements,initiate their self-regulatory behaviors,and improve their self-assessment confidence,although students still wanted to receive assistance from teachers partly due to the Confucian-heritage culture settings in *** findings are discussed in terms of the design features of sample annotations within the framework of self-regulated learning(SRL),as well as the implications of using this method in the classroom.

摘要：随着标记蛋白光转换等实验技术在生物科研领域的开展,对激光共聚焦取图技术也提出了越来越高的要求。本文旨在以斑马鱼前脑神经发育为研究对象,建立应用激光共聚焦同步双扫描系统的实验模式。本实验将36～48h的转基因Tg(lhx5:kaede)斑马鱼胚胎麻醉固定后,以光诱导变色荧光蛋白kaede标记的前脑神经元作为实验观察目标,使用激光共聚焦同步双扫描系统的405nm紫外激光刺激扫描感兴趣区域的同时,进行488nm和559nm激光刺激取图,实时观察kaede蛋白光学信号的转换状态,并在光转换后记录紫外激光刺激区域神经元的投射形态图像。结果显示,激光刺激引起kaede蛋白从绿色转变为红色,其在感兴趣区域的分布变化指示出目标神经元的胞体位置及其轴突投射路径。由上述结果可见,激光共聚焦同步双扫描技术的应用满足了kaede蛋白光转换实验的刺激和扫描同步的要求,该技术在斑马鱼胚胎特定神经元形态发育研究中的应用,可作为神经发育研究的一种实验模式在很多实验设计中进行延伸,也为激光共聚焦双扫描技术的推广提供了一个很好的平台。

摘要：Two silicon-based ultraviolet （UV） and blue-extended photodiodes are presented, which were fabricated for light detection in the ultraviolet/blue spectral range. Stripe-shaped and octagon-ring-shaped structures were designed to verify parameters of the UV-responsivity, UV-selectivity, breakdown voltage, and response time. The ultra-shallow lateral pn junction had been successfully realized in a standard 0.5-μm complementary metal oxide semiconductor （CMOS） process to enlarge the pn junction area, enhance the absorption of UV light, and improve the responsivity and quantum efficiency. The test results illustrated that the stripe-shaped structure has the lower breakdown voltage, higher UV-responsicity, and higher UV-selectivity. But the octagon-ring-shaped structure has the lower dark current. The response time of both structures was almost the same.

摘要：在学习型模型预测控制的框架里,迭代学习控制器被用来更新模型预测控制器的设定点.在已经发表的研究成果里,学习型模型预测控制用到的是比例型的学习率,这种学习率的学习能力有限,而且怎样设计学习增益仍然是一个开放性问题.在本文中,基于内模控制理论提出的PID型的迭代学习控制器被用来更新模型预测控制器的设定点.为了方便起见,本文提出的结合算法可称为内模强化学习型模型预测控制.本文提出的算法应用在1型糖尿病人的人工胰脏闭环控制上.仿真结果显示,本算法对比于比例学习型模型预测控制可以达到更好的收敛性能,而且对非重复干扰有很好的鲁棒性.