镧改性Pt/KL沸石芳构化催化剂的研究

在Ｐｔ／ＬａＫＬ沸石催化剂中ＰｔＬａ之间存在有相互作用，伴随着Ｌａ３＋的迁移，Ｐｔ粒子更多地进入沸石孔道内部，而不是聚集于沸石外表面，因而改善了Ｐｔ的分散度。适量Ｌａ的引入既保持了Ｐｔ／ＫＬ沸石催化剂较高的芳构化性能，又能较大程度地改善其抗硫性能。     

Millimeter wave microstrip circulator

A new and unique microstrip drop-in type Y-junction circulator has been designed and developed for operation in the millimeter wave frequency region. This device utilizes NiZn ferrite as the gyromagnetic material which is mounted on a duroid substrate.     

Crystal Structure and Magnetic Property of Heteronuclear Copper—Lanthanum Carboxylate Complex

ＥｘｐｅｒｉｍｅｎｔａｌＳｙｎｔｈｅｓｉｓａｎｄｅｌｅｍｅｎｔａｌａｎａｌｙｓｉｓＬａＬ3·2Ｈ2 Ｏ (86 0ｍｇ ,2 0ｍｍｏｌ ;ＨＬ =ＣＨ2 Ｃ(ＣＨ3) ＣＯＯＨ)ａｎｄＣｕ(ＮＯ3) 2 ·3Ｈ2 Ｏ (2 4 2ｍｇ ,1 0ｍｍｏｌ)ｗｅｒｅｄｉｓｓｏｌｖｅｄｉｎｔｏ 2 0ｍＬｏｆＨ2 ＯａｎｄａｄｊｕｓｔｅｄｔｏｐＨ 4 1ｗｉｔｈＨＬ (0 1ｍｍｏｌ/ｃｍ3) .Ａｎｅｔｈａｎｏｌｓｏｌｕｔｉｏｎｏｆ 1,10 ｐｈｅｎａｎｔｈｒｏｌｉｎｅ (2 0 0ｍｇ ,1 0ｍｍｏｌ)ｗａｓａｄｄｅｄｉｎｔｏｔｈｅｍｉｘｅｄｓｏｌｕｔｉｏｎｗｉｔｈｓｔｉ…     

熔盐电解合成希土六硼化物的研究——REBO_3、LiBO_2和LiF体系熔盐电解合成RER_6

本文在800℃和空气中电解REBO_3-LiBO_2-LiF(?)盐体系合成了单相的REB_6.石墨川埚兼作容器和阳极.耐火金属棒如Cu和Mo等被悬吊在电解质中作为阴极.根据似二元体系LiBO_2-LiF和LiBO_2-LaBO_3的低熔点组成以La_2O_3、B_2O_3、Li_2CO_3和LiF为原料找到了具有较低熔点的熔盐体系.根据X射线粉末衍射,该熔体是由REBO_3、LiBO_2和LiF三个物相组成.     

聚苯乙烯/油酸/氟化镧复合纳米微球的制备、表征及抗磨性能

用种子乳液聚合的方法合成了聚苯乙烯／油酸／氟化镧复合纳米微球，通过TEM、XRD、FTIR、TG－DTA等测试手段对其结构和形貌进行了表征，并在四球试验机上考察了其摩擦学行为。结果表明，复合纳米微球具有核壳结构，平均粒径约30nm，作为新型润滑油添加剂，具有良好的抗磨性能。     

一氧化氮对水稻叶片中由镧引起的氧化胁迫的缓解作用

研究了一氧化氮(NO)对水稻中由稀土元素镧诱导的抗氧化活性的影响. 结果表明, 在100 μmol·L-1 氯化镧处理的水稻幼苗中加入10 μmol·L-1 NO供体硝普钠(sodium nitroprusside, SNP), 可以显著抑制镧从水稻根部向叶片的转运. 镧处理显著降低超氧化物歧化酶(superoxide dismutase, SOD)活性和还原型谷胱甘肽(reduced glutathione, GSH)含量, 促进叶片过氧化氢(H2O2)含量上升. 而NO则可明显阻断镧引起的这些效应, 缓解镧引起的氧化胁迫, 即NO缓解了高浓度镧对水稻的毒性.     

氧化铝柱层状镧钛酸盐的制备

本文采用分步交换法首次制得了一种新的层柱材料－氧化铝柱层状镧钛酸盐，应用Ｘ射线衍射（ＸＲＤ）、红外光谱（ＩＲ）及透射电子显微镜（ＴＥＭ）等方法对该新材料进行了表征。结果表明，此材料具有较大的层间距（ｄ＝２．０５ｎｍ，６００℃）和较高的热稳定性（＞７００℃），同时考察了合成条件的改变对该材料性能的影响     

nFe3+/nSr2+和nOH-/nNO3-对锶铁氧体纳米片结构及磁性能的影响

采用改进的水热法成功合成了单分散的纯相锶铁氧体纳米片。借助DLS、XRD、FTIR、SEM、EDS和VSM等分析测试手段对SrFe₁₂O₁₉铁氧体粉体的粒度、结构、形貌和磁性能进行表征。研究结果表明,在240℃保温5 h,物质的量之比n_Fe³⁺/n_Sr²⁺(R_F/S)和n_OH^-/n_NO^-(R_O/N)分别为5和2时,所得产物为单分散的纯相六角SrFe₁₂O₁₉铁氧体纳米片。随着R_F/S和R_O/N的变化,合成样品中有少量SrCO₃和Fe₂O₃杂相存在,这主要与反应条件和离子比例有关。磁性能测试结果显示,所得纯相的六角SrF₁₂O₁₉铁氧体纳米片具有优异的磁性能,其饱和磁化强度和矫顽力分别达到60.91 emu·g^-1和94.83 kA·m^-1,使其在医疗、催化和生物等高技术领域具有潜在的应用。     

Characterization of effects of thermal-oxidative aging on styrene-butadiene rubber/silica composites with vitamin C-lanthanum complex

A novel rubber antioxidant, vitamin C-lanthanum complex, was prepared and applied in styrene-butadiene rubber (SBR)/silica composites. The anti-aging behavior of SBR/silica composites with vitamin C-lanthanum complex was systematically investigated by mechanical property retention after aging, oxidation induction time, exothermic enthalpies of thermal oxidation, and thermo-oxidative degradation kinetics. The highlight of this work lies in the fact that several thermal analysis techniques were successfully applied to fully evaluate the thermal-oxidative aging of SBR/silica composites and the vitamin C-lanthanum complex was found to endow SBR/silica composites with better protection against aging than commercial antioxidants, which may be beneficial for better characterization of rubber aging and fruitful for the preparation of highly aging-resistant rubber composites, respectively.