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铜精炼阳极炉用镁-铬耐火材料内衬的气相腐蚀(英文)

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硅酸盐学报 2003年第1期31卷 70-73页

作者： SHARIfI R RAHIMI A golestani-fard f KHANLARY H Sarcheshmeh制铜集团伊朗Rafsanjan***

镁铬耐火材料是铜精炼阳极炉风口常用的耐火材料。除热化学和热机械损耗之外 ,内衬还要经受气相腐蚀损坏。这里介绍了在伊朗Sarcheshmeh制铜集团 (complex)的阳极炉中气相腐蚀的研究结果。由XRD和SEM /EDX对用后的铬镁耐火砖进行了分析... 详细信息

镁铬耐火材料是铜精炼阳极炉风口常用的耐火材料。除热化学和热机械损耗之外 ,内衬还要经受气相腐蚀损坏。这里介绍了在伊朗Sarcheshmeh制铜集团 (complex)的阳极炉中气相腐蚀的研究结果。由XRD和SEM /EDX对用后的铬镁耐火砖进行了分析。结果表明 :在温度约 90 0℃时 ,耐火内衬因碳沉积而开始破坏。由于耐火材料中含有铁相而使耐火材料的气孔中碳沉淀更加严重。然而对于低铁的铬镁耐火内衬 ,这种腐蚀将是轻微的。对于尖晶石类耐火材料 ,未观察到内衬破坏。

关键词：铜精炼阳极炉镁铬耐火材料内衬气相腐蚀

Wear of MgO-C Refractories in EBT Type furnaces Experienced at Iranian Mobarakeh Steel Plant

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China's Refractories 2002年第4期11卷 3-8页

作者： Ali Reza Rezaie Amir Reza Hanifi farhad golestani-fard Dept. of Metallurgy & Materials Engineering Iran University of Science & Technology Narmak Tehran 16844 IranDept. of Metallurgy & Materials Engineering Iran University of Science & Technology Narmak Tehran 16844 IranDept. of Metallurgy & Materials Engineering Iran University of Science & Technology Narmak Tehran 16844 Iran

Mobarakeh Steel Company produces 3 million tons of steel annually with eight 180 tons EBT furnaces. Different types of magnesia-carbon refractories have been employed at slagline during last 5 years. In the present study the wear and corrosion of MgO-C refractories of these furnaces have been studied via post-mortem analysis of used bricks and the observation of operational effects. Laboratory corrosion tests were also arranged to investigate the effect of slag chemistry and the mechanism of chemical corrosion . Characterization of different magnesia-carbon bricks clarified that the crystal size , type and chemistry of magnesia as well as graphite structure have the main influence on corrosion resistance. The CaO: SiO2 ratio in slag also plays a vital role in the wear of slagline refractories. The iron oxide content of slag also has a major role in graphite oxidation. Of metallurgical parameters , the electric power input and the contact time have great influence on refractories life. The results will be discussed with emphasis on particular operational factors in Mobarakeh steel plant.

关键词： Magnesia-carbon brick Electric arc furnace Wear mechanism test Iran

Accumulation of heavy metal in Platanus orientalis, Robinia pseudoacacia and fraxinus rotundifolia

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Journal of forestry Research 2013年第2期24卷 391-395页

作者： Sajjad Hosseinzadeh Monfared Mohammad Matinizadeh Anoushirvan Shirvany Ghavamedin Zahedi Amiri Reza Mousavi fard fariba Rostami Department of forestry and forest Economics Faculty of Natural Resources University of Tehran Research Institute of forests and Rangelands of Iran Expert of parks organization of Karaj municipality

Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma （ICP）. We investigated the uptaking ability of lead （Pb） and cadmium （Cd） by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index （MAI）. Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of f. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves （2.21） and f. rotundifolia had the highest MAI value for shoots （2.4）.

关键词： Platanus orientalis Robinia pseudoacacia fraxinus rotundifolia heavy metals phytoremediation

Single-Switch Unity Power factor Electronic Ballast with Continuous Input Current

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Single-Switch Unity Power Factor Electronic Ballast with Con...

Research on the Physical Characteristics for Improving the Security Perceptions of Citizens:A Comparative Analysis of Zones five and Ten of Shiraz, Iran

2005国际电机与系统学术会议

作者： S.Hassanpour f.farzaneh-fard A.faroukh-payam Department of Electrical and Computer Engineering Isfahan University of TechnologyIsfahan 84154Iran

In this paper a single-switch single-stage charge pump electronic ballast with unity power factor is introduced for the fluorescent lamps. After a comparison between basic charge pump converters, the proposed ballast circuit operation is analyzed. The simulation results with the lamp circuit modeled, justifies the converter analysis.

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Chinese Journal of Urban and Environmental Studies 2018年第3期6卷 120-135页

作者： Mohammad SEDAGHAT fard Ali SOLTANI Habib AHMADI Abdolreza PAKSHIR Shiraz University

Crime and the insecurities relating to it within urban neighborhoods are currently amongst the major concerns of urban citizens, and such issues have resulted in significant harm to their social life, to the point that urban neighborhoods are even sometimes considered to be a subcategory of urban abnormality. Such a result has arisen largely due to a lack of security in cities. The qualitative and quantitative aspects associated with the sense of security are crucial to the positive existence of urban neighborhoods, both from physical and social perspectives. A particularly important issue to consider is the safety of women and girls and the elderly in urban areas,especially at night. The goal of this study is to evaluate the role that the physical characteristics of an area playing in improving the security perceptions of urban citizens within that area. The approach of the study, given its descriptive-analytic nature, might be applied to all kinds of applied research. The study's data collection is of two forms: library documents and survey-based questionnaires. In this research, a questionnaire was developed and distributed among residents of Zones five and Ten of Shiraz, Iran. After collecting the required data, SPSS is used for the study's analysis. The study adopts a simple random sampling method, with the statistical population of the study areas being 281,341. In turn, the sample size used via application of the Cochran formula is 384. The results of the T-test and the f-test are used to analyze the differences between the independent and dependent variables. The findings of the research reveal that the average security perception in Zone Ten is 41.51, an amount higher than that in Zone five, which is *** observed difference between the averages of the Zones five and Ten confirms the hypotheses of the research. The analysis shows that such factors of physical characteristics, including parks,buildings, schools, street lighting and roads network pattern

关键词： Security security perception physical characteristics City of Shiraz