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采用密度泛函理论(DFT)的B3LYP方法对反式双氧锰(V)咔咯配合物阴离子的稳定性及其质子化物种进行了理论计算. 结果表明: 反式双氧锰(V)咔咯配合物阴离子构型稳定, 其反式双氧锰键O=Mn=O由锰原子的d轨道与两个氧原子的p轨道分别构成一个σ轨道和两个π轨道; 随着外围取代基吸电性增强, O=Mn=O键长缩短, 拉曼伸缩振动频率增大; 其质子化过程中得到两个质子的轴向氧原子与锰原子的距离超出正常化学键的范围, 从而形成水分子并脱离原来分子, 导致质子化行为是不可逆过程, 而形成单氧的咔咯锰(V)-氧配合物. 相似文献
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茶叶专用营养剂对金萱茶微量元素和黄酮的影响 总被引:1,自引:0,他引:1
为探讨茶叶专用植物营养剂对金萱茶微量元素和黄酮含量的影响,以自研制的茶叶专用植物营养剂做试验,分别以稀释300、500、800倍施用到金萱茶中,采取每轮茶施肥一次,并以喷清水、1%尿素和其它品牌的茶叶营养剂稀释300倍作参照,用等离子体原子发射光谱法和分光光度法对施用不同肥料的金萱茶微量元素和黄酮含量分别进行了测定。结果表明,施用自研制的茶叶专用植物营养剂,金萱茶Ca,Mg,Fe,Zn,Mn,Cu,B等微量元素含量大大增加,黄酮含量也显著增多,这与施加含有益活性菌体和多种酶及微量元素的肥料有关。 相似文献
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微乳法制备纳米TiO2 /SiO2的结构及光催化研究 总被引:1,自引:0,他引:1
Nanosized TiO2 and TiO2/SiO2 particles were prepared by hydrolysis of tetrabutyl titanate (TBOT) and tetraethyl orthosilicate (TEOS) in the TX-100 reverse microemulsion. These particles were characterized by TG-DSC, XRD, FTIR, TEM,N2 adsorption-desorption. Their photocatalytic activity was tested by degradation of methyl orange. The result shows that TiO2/SiO2 nanoparticles are with a monodispersed spherical phase and a uniform size distribution,and TiO2 particles are dispersed on the surface of SiO2. The band for Ti-O-Si vibration in FTIR was observed, the Ti-O-Si bond increased the stability of anatase TiO2, suppressed the phase transformation of titania from anatase to rutile. And due to the addition of SiO2, the average size of titania decreased from 38 nm in pure TiO2 to 5 nm in TiO2/SiO2. It was found, under UV light irradiation, TiO2/SiO2 particles showed higher activity than pure TiO2, and TiO2/SiO2(1/1) particles showed the highest photocatalytic activity on the photocatalytic decomposition of methyl orange, which was influenced by crystal structure, particle size, crystallinity and Surface area Characteristics. 相似文献
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