铁基抗高温磨损激光熔覆涂层强韧设计和研究 Ⅱ:Fe-Cr-C-W-Ni激光熔覆层的微观组织及性能

利用ＯＭ、ＳＥＭ、ＴＥＭ研究了Ｆｅ－Ｃｒ－Ｃ－Ｗ－Ｎｉ激光熔覆涂层熔覆态及其高温时效态的微观组织结构。结果表明激光熔覆层组织细小，具有强韧两相组成（奥氏体和Ｍ_７Ｃ_３碳化物）的微观结构特征，高温时效处理组织中有Ｍ_（２３）Ｃ_６、Ｍ_６Ｃ、Ｍ_２Ｃ等新碳化物形成。显微硬度和冲击磨损实验证实了激光熔覆态和峰值时效态熔覆层均具有良好的力学性能。

低能离子束方法制备磁性Fe-Si合金薄膜

　利用质量分离的低能离子束技术,获得了磁性Fe Si合金薄膜。利用俄歇电子能谱法(AES)、X射线衍射法(XRD)以及交变梯度样品磁强计(AGM)测试了样品的组分、结构以及磁特性。测试结果表明在室温下制备的Fe Si合金是Fe组分渐变的非晶薄膜,具有室温铁磁性。当衬底温度为300℃时制备的非晶Fe Si薄膜中有Fe硅化物FeSi相产生,样品的铁磁性被抑制。

低能离子束方法制备Fe组分渐变的Fe-Si薄膜

利用质量分离的低能离子束技术 ,获得了Fe组分渐变的Fe Si薄膜。利用俄歇电子能谱法 (AES)、X射线衍射法 (XRD)以及X射线光电子能谱法 (XPS)测试了薄膜的组分、结构特性。测试结果表明 ,在室温下制备的Fe Si薄膜呈非晶态。非晶薄膜在 40 0℃下退火 2 0min后晶化 ,没有Fe的硅化物相形成。退火后Fe Si薄膜的Fe组分从表面向内部逐渐降低。

Springsheds of the Santa Fe River Basin

Powerpoint presentation (PDF has 45 pages.)

低能离子束方法制备重掺杂Fe的Si∶Fe固溶体

利用质量分离的低能离子束方法 ,以离子能量为 1 0 0 0 e V,剂量为 3× 1 0 1 7cm- 2 ,室温下往 p型 Si(1 1 1 )单晶衬底注入 Fe离子 ,注入的样品在 4 0 0℃真空下进行热处理 .俄歇电子能谱法 (AES)对原位注入样品深度分析表明 Fe离子浅注入到 p型 Si单晶衬底 ,注入深度约为 4 2 nm.X射线衍射法 (XRD)对热处理样品结构分析发现只有 Si衬底的衍射峰 ,没有其他新相 .X射线光电子能谱法 (XPS)对热处理样品表面分析发现 Fe2 p束缚能对应于单质 Fe的峰 ,没有形成 Fe的硅化物 .这些结果表明重掺杂 Fe的 Si∶ Fe固溶体被制备 .电化学 C- V法测量了热处理后样品载流子浓度随深度的分布 ,发现 Fe重掺杂 Si致使 Si的导电类型从 p型转为 n型 ,Si∶ Fe固溶体和 Si衬底形成 pn结 ,具有整流特性

Springs and swallets of the lower Santa Fe River

Many of our surface waters go underground to the aquifer via sinkholes (or swallets) and the water is then called groundwater. Most of us rely on groundwater for our drinking water. Springs are where the groundwater comes to the surface to once again become surface waters. Below is a map of the springs and swallets of the Lower Santa Fe River.

Santa Fe River watershed conservation lands

Conservation lands, which are essential to protecting water resources in the Santa Fe River basin.

The Effect of the Thickness of Fe2 Al5 Phase Layer at Fe/Al Interface on the Mechanics Behavior of Hot Dip Aluminizing Coating

Hot Dip Aluminized Coatings with different thickness were prepared on Q235 steel in aluminum solutions with different temperature for certain time. Through tensile tests and in-situ SEM observations, the effect of the coating's microstructure on the tensile strength of the samples was studied. It was disclosed at certain aluminum solution temperature,transaction layers mainly composed of Fe2 Al5 phase got thicker with time prolonging, and this changed initial crack's extending direction from parallel with to vertical with stretching direction. The change in crack direction decreased tensile strength of samples, thus made the coating easy to break. It was concluded that the existence of thick Fe2 Al5 phase layer was the basic reason for the lowering of tensile strength of the coating.

Otley College: An Online toolkit for tutorials in rural- based FE – meeting new funding needs

As part of an LSIS Regional Response Fund project, Otley College has developed an online toolkit for one-to-one tutorials, based on research undertaken with practitioners and learners. The toolkit has been developed to meet the needs of students and tutors, and attempts to fulfil the requirement for tutorials within a new straightened funding agreement.

Crystal structure and phase transition studies in perovskite-type oxides using powder-diffraction techniques and symmetry-mode analysis : SrLnMRuO6 (Ln=La,Pr,Nd; M=Zn,Co,Mg,Ni,Fe) and ALn2CuTi2O9 (A=Ca,Ba; Ln=La,Pr,Nd,Sm)

La tesis se ha centrado en la síntesis y caracterización estructural de materiales tipo perovskita: SrLnMRuO6 (Ln=La,Pr,Nd; M=Zn,Co,Mg,Ni,Fe) y ALn2CuTi2O9 (A=Ca,Ba; Ln=La,Pr,Nd,Sm). El estudio de las estructuras de los materiales se ha realizado mediante el análisis de los patrones de difracción en polvo de rayos-X, sincrotrón y/o neutrones. En el refinamiento por el método de Rietveld de las estructuras se han sustituido las coordenadas atómicas (el método más común), por coordenadas colectivas: las amplitudes de los modos que describen la distorsión de la fase prototipo. Los resultados generales para la serie SrLnMRuO6 (Ln=La,Pr,Nd; M=Zn,Co,Mg,Ni) a temperatura ambiente se ha recogido en un diagrama en el que se han indicado las amplitudes de los modos que transforman de acuerdo a las irreps en función del factor de tolerancia, ya que todos ellos cristalizan en la misma fase monoclínica (P21/n); y a temperaturas altas se ha construido un diagrama de fase. Los materiales SrLnFeRuO6 ( Ln=La,Pr,Nd) y CaLn2CuTi2O9 cristalizan en la fase ortorrómbica Pbnm a temperatura ambiente; mientras que BaLn2CuTi2O9 tienen una estructura más simétrica, I4/mcm. A altas temperaturas se han identificado las transiciones de fase inducidas por el cambio de temperatura.A temperaturas bajas se han analizado las estructuras magnéticas de algunos de los compuestos mediante difracción de neutrones.