A New Strategy for Preparation of NiAl Bronze/Zn Composite by Friction Stir Processing

In this work, we successfully prepared a NAB/Zn composite using Zn wires by friction stir processing (FSP). During FSP, Zn-containing α matrix and (Fe, Ni)Al phases and nano α and CuZn grains with the size of less than 10 nm are formed on the top surface. The average microhardness of the composite is increased by 15 pct compared with the alloy without Zn, which originates from fine grains, CuZn particles strengthening, and more β′ phase.

     

Substrate Stimulated Orientation for Pure Aluminum

Oriented materials are of great importance, but their formation is rarely described. Here, nine Al/Al₂O₃ systems were designed to identify the dominant factors. Electron back-scattered diffraction indicates that the new Al crystal(s) with one or multiple orientation(s) can be stimulated by one single-crystal Al₂O₃ substrates. Synchrotron radiation diffraction shows that the preferred orientation(s) is/are determined based on the initial stage of the liquid–solid transition. The nonpreferred orientation can be suppressed through competition.

     

Study on Dynamic Behavior of Single-Layer Reticulated Dome by Shaking Table Test

International Journal of Steel Structures - Large-span space structures in the form of reticulated domes, which have developed rapidly in the last three decades, are widely used in large-scale...     

有限方向检测法在高程点线矛盾检查中的应用

地形图生产中,对于人工采集的等高线和高程点,需要检查两者之间是否存在矛盾。在介绍常规高程点线矛盾检查方法的基础上,提出了一种有限方向检测法检查高程点线矛盾检查的手段,阐述了有限方向检测法的基本原理,给出提高方法运行速度和节约方法占有内存的措施。并编写了相应的程序,通过实际生产验证表明:该方法检查结果正确,检查速度快,适应性强,很少发现漏判,没有发现误判。     

城乡统筹背景下镇域规划编制办法研究——以广东省四会市江谷镇总体规划为例

小城镇是我国最基础的行政单元,是联系城市与农村的纽带。随着城乡统筹发展、社会主义新农村建设、推进城镇化、扩大内需等战略的不断推进,城镇规划覆盖到广大农村地域的要求越发强烈,镇域规划已经成为当前城乡规划发展的迫切需要,探索其编制方法,有助于弥补现行规划体系对小城镇规划指导的不足。编制镇域规划,首先应将规划用地分类覆盖全镇域,然后统筹镇域各类用地空间管制,进行综合分区管制,即划分禁止建设区、限制建设区、适宜建设区和已经建设区,形成合理的村镇体系、完善的交通基础设施网络、优化的公共服务设施,最后应通过将规划转化为政策文件和行动计划,以及制定开发强度控制要求来加强规划的可操作性。     

Priority setting in maintenance management: a modified multi-attribute approach using analytic hierarchy process

In the current economic climate, budgets for the maintenance of public buildings are unlikely to meet the ever-increasing maintenance needs. Although it is unlikely that this problem can be overcome completely without an injection of further resources, it is possible for government maintenance authorities to improve the situation by ensuring that the best solution in terms of ‘value for money’ is achieved in the planned maintenance programme. A maintenance plan which is based on a rational assessment of priorities and up-to-date knowledge of the condition of the property stock will help to ensure the best use of available resources. Based on the multi-attribute maintenance prioritization model developed by Alan Spedding, Roy Holmes and Qiping Shen at the University of West of England, which is simple in practice and flexible from a management point of view, this paper presents the results of some further research into this area by modifying the original model using an analytical hierarchy process in deciding the weightings of the criteria set out in the prioritization model. This modified model is more quantitative and objective than the original model. The validation of the framework is also discussed.     

Role of molecular structure on bioelectrochemical reduction of mononitrophenols from wastewater

The effect of nitro-substituent on mononitrophenol (o-nitrophenol (ONP), m-nitrophenol (MNP) and p-nitrophenol (PNP)) reduction in a bioelectrochemical system (BES) was investigated in this study. The results show that the removal of all three nitrophenols was significantly enhanced with more negative cathode potential and shortened hydraulic retention time in the BESs. Moreover, the reduction of the three nitrophenols followed in the order of ONP > MNP > PNP in the BESs. Both quantum chemical calculation using density function theory and cyclic voltammetry analysis confirmed the reductive sequence of the three nitrophenols. In addition, the acute toxicity of nitrophenol effluent significantly decreased while its biodegradability was enhanced after treatment in the BES. Therefore, the BES technology offers bright prospects for efficient treatment of nitrophenol-containing wastewater.     

台风“梅花”影响下近地风脉动特性研究

由建立在上海东海岸边的40m测风塔对台风"梅花"影响过程中的风速、风向等信息进行了全程记录,获得了10m、20m、30m及40m高度处的实测数据。通过对湍流度、阵风因子、峰值因子等脉动风特性参数的分析表明:当风速较低时,湍流度和阵风因子均随平均风速的增大而减小,但当平均风速超过其临界值时,湍流度和阵风因子基本不随平均风速而变化,两者的临界风速分别约为10m/s和12m/s;纵向和横向阵风因子随相应湍流度的增大而增大,并且通过最小二乘拟合得到了它们之间的经验公式;峰值因子(阵风持续时距t=3s)基本上不随10min平均风速的变化而变化,10m、20m和40m高度的各时段峰值因子的均值分别为2.21、2.12和2.00,峰值因子均值随阵风持续时距的变化关系与Durst研究结果较为吻合。     

超高层建筑设计风荷载的选用

在超高层建筑的结构设计过程中,各种参数的使用和指标的控制十分重要,高层建筑对风力作用较敏感,使得风荷载的取值显得较为重要,本文将借助工程实例进行分析,供大家参考。     

中国传统哲学精神在台湾现代建筑创作中的表达

从20世纪90年代开始,台湾建筑师更加关注传统哲学精神中的禅宗、儒家和道家思想。本文阐述90年代至今中国的传统哲学精神在台湾现代建筑创作中渗透的观念和实践,并从中和精神、天人合一、空无虚静三方面进行解读。