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镧三元配合物的合成、热稳定性及生物活性 总被引:8,自引:0,他引:8
在甲醇介质中,用La(ClO4)3•nH2O与丙氨酸(CH3CHNH2COOH,简称Ala)及咪唑(C3H4N2,简称Im)或苯并咪唑(C7H6N2,简称BenIm)合成出两个新三元配合物La(Ala)3Im(ClO4)3•3H2O(简称La1)和La(Ala)3BenIm(ClO4)3•H2O(简称La2).对配合物进行了容量分析及元素分析,确定了其组成.通过IR、UV、XRD及TG-DTG、DSC进一步研究了配合物的配位行为及热稳定性.生物活性试验表明该类配合物对5种菌均具有不同程度的抑制作用. 相似文献
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Europium(Ⅲ) compound with 2-oxopropionic acid salicyloyl hydrazone (C_(10)H_(10)N_2O_4,H_3L) and 1,10-phenan-throline (C_(12)H_8N_2,phen) has been prepared.A yellow prismatic crystal of the compound was obtained,and themolecule crystallized in the triclinic space group P-1.There are two 9-coordinated complex molecules in everystructure unit,where every Eu atom is coordinated by three water molecules and two tridentate C_(10)H_(10)N_2O_4 ligands,forming two stable pentacycles.The coordination polyhedron around Eu~(3+) was described as a single cap squareantiprism.In the crystal cell,there are one free 1,10-phenanthroline and four water molecules.The thermaldecomposition of the compound and its kinetics were studied by non-isothermal thermogravimetry.The Kissinger'smethod and Ozawa's method were used to calculate the activation energy value of the first-step decomposition.Thestages of the decompositions were identified by TG-DTG-DSC curve.The non-isothermal kinetic data were ana-lyzed by means of integral and differential methods.The possible reaction mechanism and the kinetic equationswere investigated by comparing the kinetic parameters. 相似文献
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汽油/氧气预混火焰中烯丙基自由基的真空紫外光电离研究 总被引:1,自引:0,他引:1
分子束取样结合同步辐射光电离质谱技术研究了低压汽油/氧气/氩气预混火焰中的烯丙基自由基,测得了它的光电离效率曲线,通过光电离效率曲线得到烯丙基的电离阈值为(8.13±0.02)eV。另外,用从头算分子轨道理论得到了烯丙基及其阳离子的构型和能量,给出了烯丙基自由基的绝热电离能为8.18 eV。计算的电离能与实验得到的电离能符合得很好,这一结果有助于今后鉴别和分析其它火焰中的烯丙基自由基,且对研究火焰燃烧机理有十分重要的价值。 相似文献
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针对多元函数稳定点处二阶偏导数全为0的情况,提出了有效的极值判别法.定义了广义n维方阵、n次型及其正定性;提出了更具普遍意义的极值充分条件;得到了利用n次型的正定性判断n元函数极值的方法并举例验证了结论的正确性和有效性. 相似文献
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右旋糖苷是由与α-(1→6)相连的d-右旋糖主链组成、结构和性能多样性取决于菌种选取的生物材料。文章综述了基于右旋糖苷的高分子材料的研究进展,第一部分主要涉及右旋糖苷的结构、特性、制备与应用。 相似文献