上海保障性住房中脱硫石膏隔墙、顶棚保温节能效果理论计算与实测

由于居民户与户之间并非同时使用空调,隔墙和顶棚存在传冷或传热现象,因此,隔墙和顶棚保温对于减少空调能耗起着重要作用。以上海地区浦江镇保障性住房中的典型住宅建筑为例,通过专业能耗模拟软件和现场实测,分析脱硫石膏保温砂浆用于隔墙和顶棚中的节能效果。     

建设项目电梯配置依据及运力计算初探

本文通过笔者总结多年的房地产项目设计、开发和运营管理经验,尝试找到一个比较简便的电梯运力计算模型,作为建设项目电梯设计和配置的参考依据。     

First principle investigation of electronic structure of CaMnO3 thermoelectric compound oxide

First principle calculations are employed to investigate the anti-ferromagnetic CaMnO₃ with regard to its geometry, ground state electronic structure and charge distributions. The G-type anti-ferromagnetic CaMnO₃ is found to be more stable via total energy minimization calculations; the calculated energy band structure reveals its band gap of 0.7 eV. There are combinations of light carriers in conduction bands and heavy carriers in valence bands that should favor high thermoelectric properties. The Mnd and Op orbitals are responsible for energy bands near Fermi level and they contribute to electronic property. There is strong hybridization between Mnd and Op orbitals and, the hybridization between Mn and O1 orbitals is stronger, it is indicated that the charge carriers are apt to transport along Mn-O1.     

Poly(L‐lactide)/polypropylene blends: Evaluation of mechanical,thermal, and morphological characteristics

Poly(L lactide) (PLA) was blended with polypropylene (PP) at various ratios (PLA:PP = 90 : 10, 80 : 20, 70 : 30, and 50 : 50) with a melt‐blending technique in an attempt to improve the melt processability of PLA. Maleic anhydride (MAH)‐grafted PP and glycidyl methacrylate were used as the reactive compatibilizers to induce miscibility in the blend. The PLA/PP blend at a blend ratio of 90 : 10, exhibited optimum mechanical performance. Differential scanning calorimetry and thermogravimetric analysis studies showed that the PLA/PP/MAH‐g‐PP blend had the maximum thermal stability with the support of the heat deflection temperature values. Furthermore, dynamic mechanical analysis findings revealed an increase in the glass‐transition temperature and storage modulus with the addition of MAH‐g‐PP compatibilizer. The interaction between the compatibilizers and constituent polymers was confirmed from Fourier transform infrared spectra, and scanning electron microscopy of impact‐fractured samples showed that the soft PP phase was dispersed within the PLA matrix, and a decrease in the domain size of the dispersed phase was observed with the incorporation of MAH‐g‐PP, which acted as a compatibilizer to improve the compatibility between PLA and PP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

On the need for the use of error‐controlled finite element analyses in structural shape optimization processes

This work analyzes the influence of the discretization error associated with the finite element (FE) analyses of each design configuration proposed by the structural shape optimization algorithms over the behavior of the algorithm. The paper clearly shows that if FE analyses are not accurate enough, the final solution provided by the optimization algorithm will neither be optimal nor satisfy the constraints. The need for the use of adaptive FE analysis techniques in shape optimum design will be shown. The paper proposes the combination of two strategies to reduce the computational cost related to the use of mesh adaptivity in evolutionary optimization algorithms: (a) the use of an algorithm for the mesh generation by projection of the discretization error, which reduces the computational cost associated with the adaptive FE analysis of each geometrical configuration and (b) the successive increase of the required accuracy of the FE analyses in order to obtain a considerable reduction of the computational cost in the early stages of the optimization process. Copyright © 2011 John Wiley & Sons, Ltd.     

消除热轧带钢头尾划伤缺陷

针对热轧带钢下表面头尾145m内出现线状划伤缺陷问题,通过统计划伤卷的轧制单位、钢种、划伤位置,分析了划伤与轧线高度的对应关系及划伤产生趋势,通过调整下阶梯垫目标高度、F7压差等,排除了调整下阶梯垫目标高度后潜在的刮伤下支撑辊辊面的问题,有效消除了带钢头尾划伤缺陷的产生,提高了热轧产品的表面质量。     

输配电价测算方法的研究

电力改革是电力行业发展的必然趋势,输配电价独立核算是电力、电价改革的核心。通过对输配电价的测算方法的深入分析．详细介绍了如何科学合理地对其按电压等级和不同用户进行分类定价。