Single-aging characteristics of 7055 aluminum alloy

The microstructures and properties of 7055 aluminum alloy were studied at different single-aging for up to 48 h using hardness test, tensile test, electrical conductivity measurement, XRD and TEM microstructure analysis. The results show that at the early stage of aging, the hardness and strength of the alloy increase rapidly, the peak hardness and strength are approached after 120 ℃ aging for 4 h, then maintained at a high level for a long time. The suitable single-aging treatment of 7055 alloy is 480 ℃, 1 h solution treatment and water quenching, then aging at 120 ℃ for 24 h. Under those condition, the tensile strength, yield strength, elongation and electrical conductivity of the studied alloy are 513 MPa, 462 MPa, 9.5% and 29%（IACS）, respectively. During aging, the solid solution decomposes and precipitation occurs. At the early aging stage of 120 ℃, GP zones form and then grow up gradually with increasing ageing time. η′ phase forms after ageing for 4 h and η phase starts to occur after 24 h aging.     

LXRF立式热解气化焚烧炉技术及生活垃圾焚烧系统

介绍了一种我国具有自主知识产权的新型垃圾焚烧技术和相关设备,对其与其它炉型的比较、工艺流程、焚烧机理等几个方面进行了详细的阐述,突出了该技术的特点和技术优势。此种垃圾焚烧技术在国内具有较好的应用价值和良好的市场前景,是一种高效低排放的垃圾焚烧实用技术。     

LXRF立式旋转热解气化焚烧炉焚烧优化控制与诊断系统

简要介绍了LXRF型立式旋转热解气化焚烧炉的工艺流程,重点阐述了LXRF立式旋转热解气化焚烧炉焚烧过程的计算机优化和诊断系统的原理和构成。本系统适用于大型垃圾焚烧电站的自动化控制和运行管理过程,可以大大改善焚烧炉的技术和经济运行指标。     

Analysis of Pulverized Coal by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy （LIBS） has been used to detect atomic species in various enviromnents. The quantitative analysis （C, H, O, N and S） of representative coal samples are being carried out with LIBS, and the effects of particle size are analyzed. A powerful pulse Nd：YAG laser is focused on the coal sample at atmosphere pressure, and the emission spectra from laser-induced plasmas are measured by time-resolved spectroscopy, and the intensity of analyzed spectral lines is obtained through observing the laser plasma with a delay time of 0.4 #s. The experimental results show that the slope of calibration curve is nearly 1 when the concentration of the analyzed element is relatively low, and the slope of curve is nearly 0.5 when the concentration of C is higher than other elements. In addition, using the calibration-free model without self-absorption effect, the results show that the decreasing of particle size leads to an increase of the plasma temperature.     

TEM study on microstructures and properties of 7050 aluminum alloy during thermal exposure

The microstructures of 7050 aluminum alloy under different thermal exposure conditions were investigated by means of transmission electron microscopy (TEM), high resolution electron microscopy (HREM) and tensile test. Guinier preston (GP) zone and η′ phase are the main precipitates in original 7050 alloy. The orientation relationship between η′ and matrix is

and

. When the alloy is exposed at different temperatures for 500 h, with the thermal exposure temperature increasing, it can be seen under TEM that the precipitates become larger and the width of precipitate free zones (PFZ) becomes larger. The higher temperature the alloy is exposed at, the more the strength is reduced. Both GP zones and η′ precipitates getting coarser and the PFZ getting wider should be responsible for the strength decline and elongation rise of 7050 alloy during thermal exposure.     

循环流化床锅炉燃烧专家控制系统研究

从循环流化床锅炉(CFBB)的运行特性、系统特点出发，基于一台35t／hCFBB，开发了一套锅炉在线监测与燃烧控制系统。并在对循环流化床锅炉分析的基础上，详细阐述了循环流化床锅炉在线监测与燃烧控制系统的模糊专家控制算法以及系统的实现，并对循环流化床锅炉燃烧专家控制系统的性能进行了简单的对比分折。     

电力工业大气污染治理技术开发 的反思与模式创新

通过回顾我国大气污染治理技术的发展历程以及对我国现有大气污染治理技术的现状分析,针对我国在大气污染治理技术开发模式中存在的瓶颈,提出了一种以全方位多尺度系统级数值仿真模拟技术为核心,以要点试验和工程回归为辅助手段的新型技术开发模式,并实际应用该模式实现了大型火电机组烟气脱硫脱硝技术的开发和大规模工程应用,实现了技术的短周期开发和快速成熟。     

地铁公共区空调系统风管流量调节特性测试分析

地铁公共区间空调系统风管风量能否达到设计的要求,将严重影响地铁公共区间内部空间的空调环境的舒适性。这使得地铁空调风管的流量分配调节显得尤为重要。通过对风管流量特性的分析,结合实验测试数据,研究一种合理的三通流量调节装置,从而保证地铁公共区间的站厅层和站台层风量的分配,达到预定的风量调节。     

基于ARM处理器的TSC2046触摸屏控制器的应用

触摸屏技术经过十几年的发展已经成为一种方便、经济的人机界面输入手段。TSC2046是四线电阻式触摸屏控制器,其核心是一个具有采样和保持功能的12位逐次逼近式A/D转换器。以飞利浦公司的ARM芯片为基础,通过TSC2046触摸屏控制器和四线电阻式触摸屏构成硬件基础,在此基础上,开发了触摸屏面板控制程序。该触摸屏已应用于实际项目中,触摸效果良好。     

一种可提升光伏系统在局部阴影时发电效率的阵列连接策略

为提升光伏系统在局部阴影时发电效率,给出一种光伏组件串联DC/DC变换器作为基本单元进行串并联形成新的光伏阵列形式——分布式直流变换器光伏阵列。将DC/DC选为Buck变换器,通过每一块光伏组件所串联的Buck变换器来跟踪该光伏组件的最大功率,从而实现所有组件在辐照不均匀以及制造差别等因素造成的输出特性不一致时仍能最大功率跟踪,在避免复杂的最大功率跟踪算法的同时显著提升系统发电效率。先对该连接方式进行理论分析,证明这种方法的可行性,然后通过Matlab/Simulink搭建仿真模型,对传统光伏阵列与新的阵列进行对比,结果上课验证所提出的新阵列连接方式能显著提升发电效率。最后,通过实验进一步验证新阵列连接方式的有效性。