弱极化法腐蚀速度测试仪的研制

阐述了弱极化区四点法测定金属腐蚀速度的基本理论,并依据这一理论研制了智能化腐蚀速度测试仪及其电化学传感器。应用该仪器于现场和实验室监测了土壤介质中的不同金属的腐蚀速度     

浅谈危险品车辆运输安全隐患对策及监管措施

危险品车辆作为物流运输的特殊群体，因事故危害性大，国家巳制定了相关标准，但标准在实际执行时，人们对反光 标识缺乏相应的认识，市场监管也缺乏有效的手段。分析危险品车辆事故危害及原因，介绍国家标准法规对危险品车辆安全标识 的规定和危险品车辆反光标识市场现状，提出简单可行的对策，以加强人们对标准的认知，尽可能降低事故的发生率。     

Domain element local integral equation method for potential problems in anisotropic and functionally graded materials

An efficient numerical method is proposed for 2-d potential problems in anisotropic media with continuously variable material coefficients. The method is based on the local integral relationships (integral form of balance equation and/or integral equations utilizing fundamental solutions) and consistent approximation of field variable using standard domain-type elements. The accuracy and convergence of the proposed method is tested by several examples and compared with benchmark analytical solutions.     

Spurious potential dependence of diffusion coefficients in Li insertion electrodes measured with PITT

Diffusion coefficients of Li⁺ in insertion electrodes determined by the potentiostatic intermittent titration technique (PITT) have been reported in the literature as being potential-dependent (and thus dependent on the degree of insertion). With this PITT method the diffusion coefficients D^PITT are determined from the current response of potential-step experiments using an approach based on the Cottrell equation. This equation assumes as boundary conditions infinitely fast kinetics and a linear system with semi-infinite thickness. Using the example of a spinel-type Li_δMn₂O₄ electrode it will be demonstrated that this potential dependence of D^PITT is not real but occurs, because the inadmissible boundary condition of infinitely fast kinetics which is not fulfilled has been adopted. This will be demonstrated with the help of numerically simulated PITT data calculated with a constant diffusion coefficient D. Diffusion coefficients D^PITT calculated from these simulated PITT data are potential dependent, even though the PITT experiments were simulated with a constant diffusion coefficient D. The inadmissible boundary condition of a linear system with semi-infinite thickness applied to a bed of spherical active particles with finite radii as represented by a Li_δMn₂O₄ electrode leads to further deviations of D^PITT which will be investigated.     

The spatial distribution of Zn during galvanic corrosion of a Zn/steel couple

The spatial distribution of Zn²⁺ during galvanic corrosion of a model Zn/steel couple in 0.01 M NaCl was investigated using a scanning zinc disk electrode. The couple had a coplanar arrangement of a steel substrate with an electroplated zinc layer at the center. During galvanic corrosion, the marked changes in the Zn²⁺ concentration were confined to a thin solution layer ca. 1.0 mm thick above the couple surface. In this thin solution layer above the zinc layer, a higher concentration region of Zn²⁺ in the range of 5-18 mM extended around the zinc layer in the solution during galvanic corrosion. Conversely, above the steel surface distant from the zinc layer, the surface concentration of Zn²⁺ was almost zero during galvanic corrosion. On this surface, the precipitation of zinc corrosion products due to the hydrolysis reaction of Zn²⁺ was observed. The distribution of the Zn²⁺ concentration supported that Zn²⁺ acted as a buffer that suppressed the increased pH due to the cathodic reaction on the steel surface near the zinc layer and almost no corrosion products formed there. The spatial distribution of Zn²⁺ is discussed in relation to the distributions of potential and pH and the surface morphology of the galvanic couple.     

民机研制外包项目潜在承担方质量能力评估研究

为有效提高民机外包项目研制质量,基于AS9100标准建立了潜在承担方质量能力评估体系,结合外包项目及承担方分类,通过权重设定及模糊打分,实现不同类型外包项目潜在承担方质量能力评估及选择,并对质量能力评估方法进行了算例演示。     

The inverse design of the wind turbine blade sections by the singularities method

The aerodynamic characteristics of wind turbines are closely related to the geometry of their blades. The innovation and the technological development of wind turbine blades can be centred on two tendencies. The first is to improve the shape of existing blades; the second is to design new shapes of blades. The aspiration in the two cases is to achieve an optimal circulation and hence enhancing some more ambitious aerodynamic characteristics. This paper presents an inverse design procedure, which can be adapted to both thin and thick wind turbine blade sections aiming to optimise the geometry for a prescribed distribution of bound vortices. A method for simulating the initial contour of the blade section is exposed, which simultaneously satisfy the aerodynamic and geometrical constraints under nominal conditions. A detailed definition of the function characterising the bound vortex distribution is presented. The inviscid velocity field and potential function distributions are obtained by the singularities method. In the design method implemented, these distributions and the circulation of bound vortices on the camber line of the blade profile, are used to rectify its camber in an iterative calculation leading to the final and optimal form of the blade section once convergence is attained. The scheme proposed has been used to design the entire blade of the wind turbine for a given span-wise distribution of bound circulation around the blade contour.     

The bioclimatic design approach to low-energy buildings in the Klang Valley, Malaysia

Formulating passive energy design strategies require an understanding of the climatic influence on buildings and the thermal comfort of their occupants. This paper presents the bioclimatic approach in building design as well as the techniques which are applied to formulate various strategies in order to achieve indoor comfort conditions. The paper deals with the Bioclimatic Chart, the Building Psychrometric Chart, Mahoney Tables and the Control Potential Zones which utilise the thermal neutrality concept. Regional climatic data from the Klang Valley area in Malaysia were utilised in formulating the design strategies. The most appropriate design strategies for hot, humid regions were then deduced. The most preferred strategies found were the use of ventilation, dehumidification and shading. Consequently, a full recommendation for the integral use of these three passive methods are suggested to be used in all buildings in Malaysia.     

控制生产成本增加经济效益

本文着重讲述控制生产成本，提高经济效益方面的一点经验。首先简要介绍采取措施降低成本投入的背景、理论根据及创新点，之后分四个方面详细介绍了控制生产成本的一些主要做法。最后，以翔实的数据证明了取得的成效。     

Recycling value of building materials in building assessment systems

The selection of green building materials and products is by far the most controversial task in sustainable construction. Determining the merits of building materials and products in terms of their recycling value, which seems to be a simple matter, is a very controversial topic in building assessment systems. This paper suggests a method to assess energy savings by recycling building materials, which can be a potential indicator of recycling worth. The method takes account of material selection, construction and deconstruction technologies, and the frequency of recycling. The result of this study can be used in assessment tools as a factor separate from the embodied energy. Since embodied energy affects the potential recycling energy, another factor is defined, based on these two factors, in order to make it possible to compare and select materials correctly, based on their embodied energy and recycling potential.