棒线材无头轧制系统主要工艺过程分析

无头轧制技术是近几年在轧钢行业得以成功应用的一种新的轧制工艺,介绍了棒线材无头轧制系统的组成,并对其主要工艺过程进行了分析.     

Y-Ba-Cu-O超导涂层的研制

用等离子喷涂工艺制备了 Y-Ba-Cu-O 高临界温度超导涂层,涂层的初始转变温度为101K、零电阻温度为86K。电阻率与磁化率的测量结果表明这种超导涂层具有与烧结超导块体相类似的性能,X 光衍射谱显示出涂层主要由 YBa_2Cu_3O_(?)单相化合物组成。     

Matlab在“计算机辅助电路分析”中的应用

"计算机辅助电路分析"课程,是通过计算机仿真实验来训练学生分析和解决电路问题的能力.实践证明,将Matlab软件,特别是其中的Simulink仿真模块作为电路分析工具,引入到计算机辅助电路分析课程教学中,收到了良好的教学效果.本文以二阶电路阶跃响应问题的求解为例,介绍了辅以Matlab的五种求解方法,并对这五种方法的特点进行了比较,说明了Matlab在电路分析方面的优越性.     

High-yield synthesis of single-crystalline 3C-SiC nanowires by a facile autoclave route

Single-crystalline 3C-SiC nanowires have been synthesized in large scale through a one-step autoclave route by the reaction of SiCl₄, (C₅H₅)₂Fe and metallic Na at 500 °C. Electron microscopy investigations show that the nanowires have typical diameters of 15-50 nm, lengths up to several tens of micrometers and grow along the [111] direction. The possible growth mechanism of the nanowires is discussed.     

催化裂化技术现状及发展趋势

详述了国内外最新渣油催化裂化、多产柴油催化裂化、低碳烯烃催化裂化、生产清洁燃料催化裂化及催化剂的技术进展，同时根据我国实际情况对今后催化裂化技术的发展提出了建议。     

Hydriding and Dehydriding Characteristics of Mechanically Alloyed LaMg_(17) Ni Composite Material

Magnesiumandmagnesiumalloyshavebeenin vestigatedashydrogenstoragematerialsforseveralde cadesbecausefarmorehydrogenbyweightcanbestoredinthemthaninmostoftheothercurrentlyknownhydrogenstoragealloys .Moreover ,thehighnaturalabundanceofMg ,itslightmassandenviron mentalcompatibilitypotentiallymakemagnesiumoneofthemostprospectivecandidatesforfuturehydrogenstoragematerials .Unfortunately ,thepracticalappli cationofMganditsalloyshasbeenlimitedonlytocertainstoragedevicebecauseoftheirpoorhydriding dehydr…     

Hydrothermal synthesis of hexagonal ZnO clusters

Hydrothermal process was applied to synthesize zinc oxide nanocrystals. X-ray powder diffraction and scanning electron microscopy were used to analyze the crystal structure and surface morphology. XRD pattern analysis showed that the ZnO clusters are single hexagonal phase of wurtzite structure (space group P63 mc) with no impurity of Zn and Zn(OH)₂. Also, SEM images revealed that the size of a single ZnO crystal is between 200-500 nm in diameter and 2-5 μm in length. The influence of potassium iodide (KI) as a surfactant on the crystallinity of ZnO has been investigated.     

动力配煤高温复合固硫剂研究

分析了高温复合固硫剂各成分的作用，实验研究了在不同配比的燃烧试验下，各成分对燃煤着火和燃烧以及对炉渣固硫的影响，得出了该煤种高温复合固硫剂的最佳配方。     

RF-MBE生长的AlGaN/GaN高电子迁移率晶体管特性

用射频分子束外延技术研制出了室温迁移率为10 35 cm2 /(V·s) ,二维电子气浓度为1.0×10 1 3cm- 2 ,77K迁移率为2 6 5 3cm2 /(V·s) ,二维电子气浓度为9.6×10 1 2 cm- 2 的Al Ga N/Ga N高电子迁移率晶体管材料.用此材料研制的器件(栅长为1μm,栅宽为80μm,源-漏间距为4μm )的室温非本征跨导为186 m S/m m,最大漏极饱和电流密度为92 5 m A/m m,特征频率为18.8GHz.     

对苯二甲酸精制技术的研究进展

综述了对苯二甲酸精制技术的研究进展，对几种主要的精制方法进行了对比，并指出了对苯二甲酸精制技术的发展趋势。