冷却速度对含Ti非调质钢中晶内铁素体形成的影响

观察了不同冷速下获得的含Ti非调质钢的显微组织,并绘制了静态连续冷却转变曲线(CCT曲线).结果表明,在0.5～2.5℃/s的冷速范围内,会有晶内铁素体析出,其中在2℃/s冷却时可以获得大量针状铁素体.空冷条件下获得细小无序分布的晶内铁素体,明显提高试验用含Ti非调质钢的韧性.     

HN2154非调质钢过冷奥氏体连续冷却转变曲线研究

采用热膨胀仪、金相显微镜与维氏硬度计对轿车前悬挂前后控制臂HN2154高氮非调质钢的过冷奥氏体在不同冷速条件下的连续冷却转变曲线(CCT)进行了测定,观察和测试了该试验钢在不同冷却条件下的组织号性能.结果表明,所测定的CCT曲线的可靠性已经得到实际工业生产的验证.     

改质沥青对冶金炼焦过程单种煤成焦性质的影响

 针对宣化钢铁公司焦化厂所用的种煤,分别研究改质沥青的加入量,对灰分Ad、挥发分Vdaf、硫分St,d、收缩指数X和煤粘结指数G等主要成焦性能的影响。研究表明：加入改质沥青小于5％时,对瘦煤、1/3焦煤、焦2煤和弱粘煤的灰分、硫含量的影响不大,对弱粘煤、1/3焦煤和瘦煤的粘结指数没有明显的影响,对弱粘煤和瘦煤的胶质层厚度影响也不明显;随着改质沥青的加入,焦2煤和1/3焦煤的胶质层厚度显著增加,焦2煤的粘结性指数也显著增加。加入改质沥青大于5％时,随着改质沥青的加入,瘦煤和弱粘煤的灰分下降明显,焦2煤硫含量降低增大,瘦煤的胶质层厚度显著增加,弱粘煤、1/3焦煤和瘦煤的粘结指数有明显增加。加入改质沥青对各单种煤收缩指数影响规律较复杂,弱粘煤和1/3焦煤的收缩指数在配入3%改质沥青降到最小,以后又都明显增大,但改质沥青达到5%~6%后又减小;焦2煤和瘦煤在加入量小于5％时,收缩指数变化不大,加入量大于5％时才明显减少。     

Reaction between Lanthanum and Phosphorus in Steel

P always causes low temperature emhrittlement and temper embrittlement owing to itsgrain boundary segregation[']. Garcia C I etal. [2) reported a complex compound containingLa, O I S and P, in which LaZOZS acted as anucleation site and Fe-P precipitated on thesurface of the oxysulfide. Nevertheless, thermodynamic calculation by Seah M P showedthat La could not react with P in steel unlesstemperature is lower than 1100 T, sinceGibbs free energy of formation of LaP is positive above thi…     

Excel在企业工时定额工作中的应用

将Excel引入企业工时定额管理进行数据分析.     

Y/Eu co-doped TiO2:synthesis and photocatalytic activities under UV-light

Y and Eu co-doped nano-TiO2 photocatalysts were successfully prepared via a sol-gel method and characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), ultraviolet-visible spectrophotometry(UV-vis), photoluminescence(PL) and Fourier transform infrared(FT-IR) spectra. Experimental results indicated that Y and Eu doping inhibited the growth of crystalline size and the transformation from anatase to rutile phase and had the function of reducing particle reunion. At the same time, co-doping could also enhance the absorption in visible region and then narrowed the band gap. The photocatalytic activities of the samples were evaluated by the degradation of methylene blue(MB) under ultraviolet(UV) light irradiation, which showed much enhanced photocatalytic activities over un-doped TiO2. The degradation rate of 1.5% Y/Eu-TiO2 of methylene blue was 86%, which was about 5 times of that of un-doped TiO2, and the possible reasons for the improvement of photocatalytic activities were analyzed. In this experiment, the dopant amount of rare earth was 1.5% and the ratio of Y:Eu was 2:3 for the maximum photocatalytic degradation, and the sample calcined at 500 oC showed the best reactivity. For the best samples above, the removal rate of phenol under visble light was 53% whthin 2 h.     

基于单片机的红外测温仪设计

设计以单片机作为整个测温仪的核心,结合A/D转换器、液晶显示器等外部设备,在软件设计和硬件设计的基础上,设计出一种拥有汉字显示逻辑判断等智能型电子测温计。它提供了一种新的温度测量方案,采用红外温度传感器来测量温度信号,可同时测量目标温度和环境温度,并将测量的数据经过放大器,转换器送给单片机处理,之后送数码管显示。红外测温打破了传统的测温模式,它响应快、测量精度高、可靠性高、范围广,为非接触测量,因而不易损坏。该温度计以准确快捷的测量功能、清晰易懂的数字化显示方便人们日常生活使用。     

ZigBee无线传输技术综述

ZigBee技术是一种新兴的短距离、低复杂度、低功耗、低数据速率、低成本的无线网络技术。ZigBee协议采用IEEE802.15.4标准的物理层和链路层,并在其上增加了网络层,安全模块和应用支持子层模块,从而实现了大区域网络覆盖。ZigBee由于其在低功耗、低复杂度、自组织等方面的优势,逐渐成为无线传感器网络的首选通信协议。     

火灾烟雾报警系统的设计

主要对火灾报警控制器的理论做了深入的研究,使用单片机,选用烟雾传感器、红外传感器等多个传感器作为敏感元件,结合信息融合技术,全面阐述了研制火灾报警控制器硬件部分和软件部分的方法。采用protel99绘制电路图并进行电路仿真,证明整个系统电路设计合理,性能安全可靠。     

基于ARM处理器的CAN节点设计

引言随着信息技术的飞速发展,基于ARM在嵌入式系统方面的优势和CAN总线的广泛应用,目前越来越多的ARM处理器内部自带了CAN控制器,极大的方便了开发人员对CAN总线的开发。本课题是基于ARM2104的微处理器CAN总线系统节点开发,采用CAN总线可以将节点控制器直接