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杂多酸盐催化苯酚羟基化制备苯二酚反应产物的反相高效液相色谱分析胡玉才烟台师范学院化学与材料科学学院 烟台264025摘 要:建立了反相高效液相色谱法测定杂多酸盐催化苯酚羟基化制备苯二酚反应产物的分析方法.样品经稀释和经滤膜过滤处理后,在Shim-pack CLC ODS色谱柱(4.6 mm i.d.×150 mm,5μm)上,以甲醇-水(V(甲醇)∶V(水)=35∶65)+体积分数1%乙酸为流动相,流速为1.0 mL/min,柱温为40℃,紫外检测波长280nm,8 min内可以将对苯二酚,邻苯二酚和苯酚完全分离并定量,三者的线性范围分别为0.010.60,0.010.50,0.051.00 mg/mL.反应后在及时分析样品的前提下,该法适合进行苯酚羟基化的产物分析.关键词:反相高效液相......
毛细管液相色谱法分离植物内源激素徐卉1,2,贾丽1,柳亚玲11. 华南师范大学激光生命科学教育部重点实验室,激光生命科学研究所2. 汕头大学理学院摘 要:建立了毛细管液相色谱法(CLC)同时分离测定4种植物内源激素的方法.采用硅胶基质ODS整体柱(27cm×100μmi.d.)作为分离柱,以带有光程为3mm的光纤检测池的紫外检测器作为检测手段,在室温下以含10mmol/L乙酸(pH3.0)的V(甲醇)∶V(水)=35∶65为流动相,以0.6μL/min的流速进行等度洗脱.采用溶剂梯度效应和扩展光程的检测池来提高检测灵敏度,该方法测定4种植物内源激素的检出限(S/N=3)在27.7~196.1ng/mL之间,峰面积和保留时间的相对标准偏差(RSD)小于2.8%.方法已用于不同种类玉米样品的测定......
to an appearance of a platform in the kinetic curve of static recrystallization. Different from the conventional micro-alloying steel,the strain-induced precipitates in 403Nb steel during hot rolling......
University摘 要:The micro-alloying effects of Y on the microstructure, mechanical properties, and bio-corrosion behavior of Mg69-xZn27Ca4Yx(x= 0, 1, 2......
Fabrication and characterization of novel biodegradable Zn-Mn-Cu alloysZhang-Zhi Shi,Jing Yu,Xue-Feng Liu,Lu-Ning WangSchool of Materials Science and Engineering, University of Science and Technology Beijing摘 要:Zn-Mn-Cu alloys with micro-alloying of Mn and Cu in Zn are developed as potential biodegradable metals. Although the as-cast alloys are very......
in order to acquire high quality laser cladding coating. Strengthened effect mechanism of rare earth additive is concluded, and the main effects of rare earth additive are micro-alloying, purifying boundary......
L-丙交酯/ε-己内酯配比对共聚物微结构和性能的影响王勤,王传栋,刘阳,马丽霞山东省医疗器械研究所山东省医用高分子材料重点实验室摘 要:辛酸亚锡催化下开环聚合制备不同物质的量比L-丙交酯/ε-己内酯(LLA/CL)共聚物.核磁共振(1H和13C-NMR)结果表明,共聚物组成与投料比基本一致,聚合过程中酯交换反应导致序列结构重新分布,二级酯交换系数(TII[CLC])随CL用量增加而增大.共聚物组成明显影响单元序列长度,各序列长度随相应单体投料量增加而增大,CL投料比≤50%的平均序列长度(LLL和LC)与相应的无规序列长度(LRC和LRLL)较接近,共聚物趋于无规分布.差示扫描量热(DSC)和广角X射线衍射(WAXD)表明共聚物是结晶态聚合物,结晶性与单元序列长度密切相关.共聚物组成显著影响其力学性能......
of mechanical and microstructural behavior. Also this result provided a reasonable evidence for micro-alloying of RE in DSSs.关键词:......
ferritic stainless steels with different Ti and/or Nb micro-alloying were investigated both experimentally and theoretically.It was found by the grain structure observation that the addition of Ti......
of mechanical and microstructural behavior. Also this result provided a reasonable evidence for micro-alloying of RE in DSSs.关键词:......