尼龙11研究的发展与展望

综述了尼龙11的合成与研究应用情况，并对尼龙11的研究与发展提出了展望。

晶体取向和载荷模式对Ni_3Al合金单晶体疲劳行为的影响

在名义Ⅰ型和Ⅰ／Ⅱ复合型载荷下研究了晶体取向和加载模式对Ni3Al合金单晶体疲劳开裂行为的影响.结果表明：疲劳开裂行为强烈地依赖于晶体取向和加载模式.在单晶体中，疲劳裂纹总是沿着具有最大切应力的滑移面开裂.根据单晶体的实验结果，解释了用三种主要的复合型断裂准则所预测的多晶体在复合型加载下的疲劳开裂行为.

稀土复合氧化物纳米微晶RE_2Sn_(2-x)B'xO_7的制备、结构和红外光谱(RE=Sm,Ce;B’=Fe,Co,Ni;x=0～1.0)

采用非醇盐溶胶-凝胶法首次制备了未见报道的B位掺杂烧绿石型稀土复合氧化物RE2Sn2-xB'xO7（RE＝Sm，Ce；B’＝Fe，Co，Ni；x＝0～1．0）纳米微晶.发现应用该法可降低反应温度（约200℃），缩短反应时间.制备的纳米微晶属于立方晶系，空间群为Fd3m，晶胞参数与掺杂量呈线住关系．通过红外光谱的研究，发现RE＝Ce系列试样的吸收峰频率值均低于RE＝Sm系列试样的对应吸收峰频率值：B'位不同离子的掺入，不仅导致BO6八面体的变形，出现相应的吸收峰，而且影响RE-O键的振动，使其频率有所降低．

CZOCHRALSKI SILICON CRYSTAL GROWTH IN NITROGEN ATMOSPHERE UNDER REDUCED PRESSURE

The experimental results of Czochralski silicon (CZ-Si) crystal growth in nitrogen at-mosphere are reported. The chemical reaction between silicon and nitrogen under reduced pres-sures is studied. Nitrogen gas flow under reduced pressure can eliminate the SiO smokes,and high yield of dislocation-free single crystals can be obtained. Silicon with low carbonconcentration grown by this method exhibits good electrical properties. Heat treatment be-haviours of the Si crystals have been studied. After tri-step intrinsic gettering heat treat-ment, ideal clean denuded zone is formed in Si-wafers.

TEA CO_2激光器倍频研究的进展

综述了激光倍频技术的发展,并对TEA CO2激光器倍频技术进行了较为详细的分析.给出了3～5 mm激光的应用领域.