RH精炼钢中全氧量变化与操作改进

为了使钢中全氧量控制在一个适当的水平,在武钢炼钢总厂RH真空脱气装置对低碳、超低碳钢进行了脱氧净化试验.结果表明,影响全氧去除的因素按作用高低依次是出钢溶解氧水平,溶解氧与钢包渣的交互作用,钢包渣,和真空处理净化时间.通过改进工艺生产了全氧量≤10×10-6,非金属夹杂物尺寸<10μm的清洁钢水,建立了一个钢包内钢水全氧浓度随时间变化的新方程,该方程考虑了全氧的表观平衡含量及环流、扩散传质对去除氧化物夹杂速率的影响.     

SiCl_4制备正硅酸乙酯的工艺研究

为寻找一条工序简单、耗价低、易于工业放大路线,实现多晶硅副产物四氯化硅(SiCl4)废物资源化制备正硅酸乙酯(TEOS),本文以多晶硅副产物SiCl4和无水乙醇为原料制备TEOS,在半连续化生产工艺的基础上研究了SiCl4与乙醇的摩尔比、反应温度、反应时间等因素对TEOS产率及纯度的影响。正交实验优化结果表明:15℃下,以恒定速率滴加14.21 g无水乙醇于15 g四氯化硅中,反应35 min,补加8.12 g无水乙醇;55℃下恒温40 min,经减压蒸馏,除去低沸点的乙醇和氯化氢,TEOS产率达到86.61%。对正交实验优水平下制得的产物进行红外光谱(IR)和气相色谱(GC)分析,结果表明:产物中TEOS结构正确,其纯度大于99.0%,达到市售分析纯纯度。     

Magnetoresistance of the thin film ferromagnetic nanoconstrictions

The magnetoresistance and I-V characteristics at different temperatures of the thin film ferromagnetic nanoconstrictions of variable width (from 20 to 250 nm) and 10 nm thicknesses, fabricated by electron beam lithography and vacuum thin film deposition are compared. The magnetoresistance and resistance of the thin film ferromagnetic nanoconstrictions are not related to the width of the nanoconstrictions. Instead the resistance of the local nano-region in the middle of the thin film ferromagnetic nanoconstriction has only a minor role compared to that of the two microscale thin film ferromagnetic electrodes, which contribute the majority of the measured resistance. The magnetoresistances of the thin film ferromagnetic nanoconstrictions and a 0.2 cm × 0.8 cm thin ferromagnetic film deposited under the same conditions were also compared; the thin film ferromagnetic nanoconstrictions have higher magnetoresistances than the thin ferromagnetic film, which implies that the measured magnetoresistance of the thin film ferromagnetic nanoconstrictions comes mainly from the local nano-region in their centers. In conclusion, the measured magnetoresistance of the whole sample is similar to the anisotropic magnetoresistance, because the resistance of the two microscale thin film ferromagnetic electrodes is much higher than that of the local nano-region in the middle of the samples. Comparing the experimental results for the thin film ferromagnetic nanoconstrictions and the thin ferromagnetic film reveals that the magnetoresistance of the local nano-region in the middle of the sample is much higher than that of the two microscale thin film ferromagnetic electrodes attached to it.     

Deep levels,transport and THz emission properties of SiGe/Si quantum-well structures

In coal mines in such countries as China and Russia,most of the coal mine methane(CMM) generated during mining is emitted to the atmosphere without any effective usage,because the methane concentration of CMM is relatively low and not allowed to be used as fuel for safety reasons.Methane is one of the greenhouse gases.Therefore,if it becomes possible to concentrate CMM to an acceptable level for use as fuel,this will greatly contribute to reduction of greenhouse gas emissions.With the aim of gaining approva...     

晶粒尺寸和热处理对Sm2Fe17N3/Fe3N/BN软磁/硬磁复合材料的合成及磁性能影响

采用高能球磨和真空热处理方法制备Sm2Fe17N3/Fe3N/BN复合材料, 并研究球磨过程中晶粒尺寸变化对固态相变和磁性能的影响.  结果表明: Sm2Fe17N3和Fe3N相产生的条件是Fe的晶粒尺寸达到纳米量级（D＜80 nm）并形成Fe(Sm)固溶体; 随着退火时间的增加, 300 ℃真空退火的球磨样品中Sm2Fe17N3的结晶物增多, 矫顽力提高, 表明样品的磁性能与Sm2Fe17N3的结晶程度有关.     

钢中氢、氮、氧的来源及其控制

根据炼钢基本理论和生产实践积累的经验,分析了钢中O、N、H等有害杂质元素的来源,提出了上述几种有害元素的相应控制对策,给出了生产净化钢液的主要技术措施,探讨了今后待解决的重点技术问题和发展方向.     

兖州煤加氢液化性能的评价

用两种间隙式小型高压釜,在不同条件下考察了究州煤的加氢液化性能,並与联邦德国加氢原料煤Wester holt煤和美国的Illinois 6号煤进行了对比。试验结果表明:兖州煤具有较高的加氢反应活性,它略高于后一种煤,明显高于前一种煤。以循环油为溶剂,拜尔赤泥为催化剂,在氢初压9MPa,435℃和60min条件下,兖州煤的转化率达84%:油产率为46%。     

提高紫外和真空紫外光谱辐照度定标精度的一种方法

描述了一种新的紫外和真空紫外光谱辐照度的定标方法．此方法可以减少光电接收器不稳定性引入的信号误差，使校准工作具有重复性好、精度高的优点，特别适用于光谱辐射强度较弱之光源的定标．用氩气氛替代真空条件，可使真空紫外范围内的定标工作快捷方便并节约成本．     

内蒙古苦豆子Sophoraalopecuroides生物碱成分及分离研究

用薄层扫描法测定了内蒙古苦豆子中主要生物碱的含量，真空液相层析法分离总碱得八种结晶。其中七种已知生物碱。通过熔点、薄层定性、红外、核磁等理化分析比较确认为槐果碱、苦参碱、槐定碱、槐胺碱、氧化苦参碱、金雀花碱和Ｎ－甲基金雀花碱。晶（１）经ＩＲ，￣１ＨＮＭＲ及ＭＳ谱表征，初步认为是槐定碱的Ｎ－氧化物，是首次从国产苦豆子植物分离得到．     

可编程控制器在真空吸盘式机械手中的应用

介绍了可编程控制器在真空吸盘式机械手控制中应用的方法．用实例说明了以可编程控制器为核心构成的逻辑控制系统与传统的继电器接触器控制系统相比具有可靠性高、电路简单、功能强、适应性强及控制功能修改方便等优点．