预养护还原剂封层材料对老化沥青基本性能的影响

文章介绍了预防性养护中还原剂封层技术,通过测试不同种类还原剂封层材料以多种掺量掺入老化后沥青的三大指标,研究其沥青性能恢复效果,并对还原剂封层材料在沥青路面预养护中的应用进行初步探讨。     

粗糙海面的电磁散射缩比模拟测量的若干基本问题

针对实验室内难以构造的高海情PM谱海面,采用电磁缩比测量的方法研究其电磁散射特性,首先定量分析了以淡水替代海水造成不满足物理相似性要求而引入的误差,然后讨论了缩比PM谱海面满足几何相似性条件的要求,和对粗糙海面进行缩比模拟测量的途径,根据粗糙海面缩比模拟理论与条件,在实验室内成功模拟构造满足缩比测量理论的粗糙海面。     

植物激素三十烷醇

<正> 自1975年美国密执安州立大学S.K.Ries博士等人,提出三十烷醇对植物生理有一定活性后,引起了人们极大兴趣。该激素具有用量少,无公害,来源广和费用低等优点。1978年厦门大学植物激素组提出“植物激素三十烷醇研究报告”,系统地介绍了从糠蜡和蜂蜡等原料中,提取和纯制三十烷     

基于智能天线的超高输电塔变形监测技术

提出了一种基于智能天线、扩频技术的超高输电塔变形测量方案,并对系统的工作原理进行了阐述.方案通过在超高输电塔安装多个无线电信标,利用天线阵列对信标的方位、距离信息进行监测,从而得到超高输电塔的变形量.针对多信标的波达方向估计需求,提出了一种基于平面阵的二维多重信号分类的改进算法,并对算法进行了仿真分析.仿真结果表明,提出的算法可以精确估计所有信标的方位信息,可对超高输电塔的变形以毫米级精度进行实时监测.监测到的变形信息将直接用于评估超高输电塔的健康状况.     

基准声学温度计的研究进展

热力学温度是一切温度测量(包括国际实用温标)的基准,是国际上公认的最基本的温度.声学温度计是测量中低温区热力学温度精度最高的方法之一,也是定容理想气体温度计最有效的替代方法之一.综述了声学温度计测量热力学温度的研究进展,分析了目前建立声学温度计的最主要方法-球共鸣声学法的测量原理及其进展,并对声学温度计的未来发展进行了展望.     

思南公馆David Laris概念餐厅

精选理由Dariel & Arfeuillere—A Lime 388 Company在上海宣布四个新的餐饮概念室内设计项目的完工:思南公馆David Laris概念餐厅。     

基于Web的铸造工艺管理信息系统开发

根据熔炼铸造企业生产工艺的特点,提出将ASP技术与基于ActiveX报表二次开发技术应用于铸造工艺管理信息系统的方法;运用XML技术分析实现的原理,使系统在B/S模式上实现了所见即所得的设计编辑功能.系统已应用于熔炼铸造企业,大大提高了企业的管理水平.系统的成功运用将为工艺管理系统向网络化的发展提供有益的探索和借鉴.     

Performance of La0.75Sr0.25Cr0.5Mn0.5O3−δ perovskite-structure anode material at lanthanum gallate electrolyte for IT-SOFC running on ethanol fuel

Perovskite-structure La_0.75Sr_0.25Cr_0.5Mn_0.5O_3−δ (LSCM) powders were prepared using a simple combustion process. Thermal analysis was carried out on the perovskite precursor to investigate the oxide-phase formation. The structural phase of the powders was determined by X-ray diffraction. These results showed that the decomposition of the precursors occurs in a two-step reaction and temperatures higher than 1100 °C are required for these decomposition reactions. For the electrochemical characterization, LSCM anode materials and (Pr_0.7Ca_0.3)_0.9MnO₃ (PCM) cathode materials were screen-printed on two sides of dense La_0.8Sr_0.2Ga_0.8Mg_0.2O₃ (LSGM) electrolyte layers prepared by tape casting with a thickness of about 600 μm, respectively. The morphology of the screen-printed La_0.75Sr_0.25Cr_0.5Mn_0.5O_3−δ perovskite thick films (65 μm) was investigated by field emission scanning electron microscope and showed a porous microstructure. In addition, fuel cell tests were carried out using humidified hydrogen or ethanol stream as fuel and oxygen as oxidant. The performance of the conventional electrolyte-supported cell LSCM/LSGM/PCM while operating on humidified hydrogen was modest with a maximum power density of 165, 99 and 62 mW cm⁻² at 850, 800 and 750 °C, respectively, the corresponding values for the cell while operating on ethanol stream was 160, 101 and 58 mW cm⁻², respectively. Cell stability tests indicate no significant degradation in performance has been observed after 60 h of cell testing when LSCM anode was exposed to ethanol steam at 750 °C, suggesting that carbon deposition was limited during cell operation.     

The magneto-electric effect in molten salts—1. Visualization and measurement of the magneto-electric voltage in 1-ethyl-pyridinium bromide; comparison of results in the molten salt at 130 °C and in solutions in water and ethanol

The magneto-electric effect has been studied using 1-ethyl-pyridinium bromide in both the molten state and in solution in water or ethanol. The production of stable, coloured radical cations allows one to observe their movement in the cell. From the results it is possible to establish a relationship between the magneto-electric voltage and the type and behaviour of the electrolyte, to better understand the magneto-electric effect in ionic liquid media and to explain the apparent non-reproducibility of certain results. A Lorentz force causes a deviation in the trajectory of charge carriers. This deviation in current lines produces differences in charge concentration in the cell, particularly between the measurement probes. Thus the physical significance of the observed voltage is different from that of the Hall voltage described for electronic solid conductors.     

电气绝缘油引起未投运变压器绝缘电阻不合格原因分析

以某典型案例为例,在不同温度、不同储存时间下开展了不同烃组成变压器油与固体绝缘材料的相容性试验,分析并查找了原因。