城镇燃气管道随桥设计的分析与研究

本文介绍了目前合肥市燃气管道的随桥敷设方式,总结和分析了不同随桥敷设方式的特点及其存在的问题和难点,针对问题和难点提出了相应的解决方案.同时给出了不同燃气管道过桥方式需要采取的安全保护措施.为今后燃气管道随桥敷设提供了重要的参考价值.     

中国对外承包工程法律保障初步研究

本文初步研究了中国对外承包工程法律保障现状及存在的问题,提出了完善中国对外承包工程法律保障的基本原则及对策.     

LG水泥基渗透结晶型防水材料配方及性能研究

选取了三种化学活性物质与水泥、石英砂进行组合,利用均匀设计的实验方法对配方进行了优化,从而研制出了LG水泥基渗透结晶型防水涂料.经一系列的性能测试,结果表明LG涂料的各项性能指标均已达到或超过了国家标准,也不低于国外同类别产品的性能指标.     

水泥基渗透结晶型防水材料涂层基体的微观分析

运用扫描电子显微镜、X射线衍射对水泥基渗透鲒晶型防水材料（CCCW）涂层混凝土基体进行了微观分析，结果表明：CCCW的活性化学物质渗透进入混凝土内部，与混凝土基体发生化学作用生成不溶针状晶体，并且离涂层越远，所能够渗入的活性物质量越少。     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Eu(Ⅲ), β-diketones and 1,10-phenanthroline

Three novel β-diketones (HPPP, HTPP, and HFPP) ligands were synthesized by Sonogashira coupling reaction and Claisen con-densation. The structure of β-diketones was confirmed with elemental analysis, IR, NMR and MS spectra. Three new ternary complexes consisting of Eu(Ⅲ), β-diketones, and 1,10-phenanthroline(phen) were synthesized and characterized as ThL3phen (L=PPP, TPP, FPP) with elemental analysis, chemical analysis, and IR spectra, and their luminescence properties were studied.     

Synthesis and luminescence properties of rare earth ternary complexes consisting of Eu（Ⅲ）, β-diketones and 1,10-phenanthroline

Three novel β-diketones （HPPP, HTPP, and HFPP） ligands were synthesized by Sonogashira coupling reaction and Claisen condensation. The structure of β-diketones was confirmed with elemental analysis, IR, NMR and MS spectra. Three new ternary complexes consisting of Eu（Ⅲ）, β-diketones, and 1,10-phenanthroline（phen） were synthesized and characterized as TbL3phen （L=PPP, TPP, FPP） with elemental analysis, chemical analysis, and IR spectra, and their luminescence properties were studied.     

辫状河三角洲前缘储层构型分析——以彩南油田彩9井区三工河组为例

彩南油田彩9井区三工河组由于多年注水开采,油水关系十分复杂,如何提高油田开发效果已成为急需解决的问题。研究区目前开发阶段井网调整的关键是明确储层的叠置关系,即目的层三工河组二段2和3小层辫状河三角洲前缘储层构型单元分布特征。为此,首先分析彩9井区目的层沉积微相的岩电特征,建立沉积微相的单井识别标志,为进一步的井间精细对比奠定基础;然后基于单井沉积微相识别结果,根据岩心、录井及测井资料对沉积微相内部精细解剖,明确不同级别储层构型单元的识别标志;以河流相沉积模式为指导,建立井间储层构型单元的静态分布模型,实现对不同级别储层构型单元的定量表征;最后由注采动态资料的响应关系验证储层构型单元静态分布模型的合理性和准确性。研究结果表明,建立的彩南油田彩9井区三工河组储层构型单元静态分布模型与研究区实际生产情况吻合较好,对于油藏后期的开发具有指导作用。     

软土地区基坑开挖变形性状研究

对杭州及上海软土地区十几个成功基坑工程的围护体最大侧向变形、最大侧向变形位置、邻近建筑物的沉降以及变形的时间效应等进行了分析研究和总结,并与前人的研究成果进行了比较。文中还根据建筑物沉降产生机理及工程实测资料提出了一种考虑邻近建筑物存在的地表沉陷估算方法。最后得出了几个对工程界有一定参考价值的结论     

Inverse design of an indoor environment using a CFD-based adjoint method with the adaptive step size for adjusting the design parameters

The step size used in the computational fluid dynamics (CFD)-based adjoint method has a significant effect on computing time. The constant step size usually used is obtained through a time-consuming trial-and-error process. This study used an adaptive step size for adjusting the design parameters in the CFD-based adjoint method. To validate the performance of the CFD-based adjoint method with the adaptive step size, this investigation evaluated three different inverse design cases with mixed convection flow. Our results confirmed that the adaptive step size is computationally efficient and can be used for the inverse design of an indoor environment.     

Experimental study on dual recirculation of polymer electrolyte membrane fuel cell

Durability and start-up ability in sub-zero environment are two technical bottlenecks of vehicular polymer electrolyte membrane (PEM) fuel cell systems. With exhaust gas recirculation on the anode and cathode side, the cell voltage at low current density can be reduced, and the membrane can be humidified without external humidifier. They may be helpful to prolong the working lifetime and to promote the start-up ability. This paper presents an experimental study on a PEM fuel cell system with anodic and cathodic recirculation. The system is built up based on a 10 kW fuel cell stack, which consists of 50 cells and has an active area of 261 cm². A cathodic recirculation pump and a hydrogen recirculation pump are utilized on the cathode and anode side, respectively. Key parameters, e.g., stack current, stack voltage, cell voltage, air flow, relative humidity on the cathode side, oxygen concentration at the inlet and outlet of the cathode side, are measured. Results show that: 1) with a cathodic recirculation the system gets good self-humidification effect, which is similar to that with an external humidifier; 2) with a cathodic recirculation and a reduction of fresh air flux, the cell voltage can be obviously reduced; 3) with an anodic recirculation the cell voltage can also be reduced due to a reduction in the hydrogen partial pressure, the relative humidity on the cathode side is a little smaller than the case with only cathode recirculation. It indicates that, for our stack the cathodic recirculation is effective to clamp cell voltage at low current density, and a self-humidification system is possible with cathodic recirculation. Further study will focus on the dynamic model and control of the dual recirculation fuel cell system.