高灵敏分光光度法测定微量锰(Ⅶ)

研究了DCB偶氮胂与MnO_4~-的褪色反应.结果表明,在硫酸介质中褪色反应具有高灵敏度,据此建立了一种新的光度法测定微量锰(Ⅶ).实验结果表明:有色溶液最大吸收波长为540nm,表观摩尔吸光系数为2.23×10~4L/(mol cm),锰量在0.01~2.40g/mL范围内服从比尔定律.本法用于测定人发中微量锰(Ⅶ),结果满意.     

Systematically controlled synthesis of rGO/nano-MnO_x materials for supercapacitors

The effects of hydrothermal production conditions on crystal forms,morphology and electrochemical performance of in situ reduced graphene oxide/manganese oxides(r GO/Mn O_x)hybrid electrode materials were studied.The XRD/SEM results show that the ratio of precursors,reaction temperature and type of solvent significantly affected the crystal form obtained and nano-structure of MnO_x.Varied precursor ratios of KMnO_4:GO(5:1,7:1,9:1 and 11:1)yielded the hybrids of rGO/Mn_7O_(13)5H_2O,rGO/β-MnO_2,rGO/Mn_(98)O_2,and rGO/K_(0.27)MnO_2(H_2O)_(0.54),respectively,having corresponding nano structures of nano-sheets composed petal-like shape,petal-like shape based nano-wire clusters,petal-like shape with backwardly arched top and bigger mesoporous petal-like nano structures.Hybrid prepared precursor with the ratio of 5:1 exhibited the highest specific capacitance of 320 F/g at 0.2 A/g and the smallest diffusion impedance.However,hybrid prepared precursor with the ratio of 7:1 presented the lowest electron transfer impedance.Varying hydrothermal treatment temperatures(140,160 and 200℃)yielded hybrids:rGO/MnO(OH),rGO/Mn_(0.91)O_(1,82)(H_2O)_(0.18),and rGO/Mn_7O_(13)5H_2O,respectively.The nano structures of the hybrids were nano-sheets having petal-like mesoporous structure,but having larger dimensions as temperature increase.The hybrid prepared at 160℃ showed the highest specific capacitance of 214 F/g at a current density of 0.2 A/g and the lowest solution resistance of1.61Ω,whiles,the hybrid prepared at 140℃ inferred the best cyclic reversibility.     

ICP-AES测定锰矿中的微量元素

用酸消解对矿石样品进行预处理,用电感耦合等离子体发射光谱法一次测定锰矿石中的Co、Cu、Ni、Pb、Zn和Ba等6种痕量元素。采用干扰系数校正法消除共存元素对被干扰元素的影响后对锰矿石标准物进行分析,方法的相对标准偏差(RSD)为0.3%~2.5%,精密性良好,通过对待测样品的分析,样品中6种待测元素的相对标准偏差(RSD)为0.95%~4.31%,对待测元素Co和Pb的回收实验表明加标回收率为97.5%~103%,该方法分析速度快,工作量小,分析精度高,能满足锰矿石中痕量元素的分析要求。     

吸附溶出伏安法同时测定水中痕量Zn和Mn

用电化学方法同时测定多种金属离子已有一些报道 ,但在 HSCN— KSCN溶液中直接用 SCN-作配合剂 ,采用玻碳电极同位镀汞的吸附伏安法同时测定 Zn和 Mn报道甚少 ,在该体系中 Zn和 Mn的 KSCN配合物均产生灵敏的吸附波 ,峰电位分别是 -1 .1 4 V和 -1 .5 6 V( vs,Ag/Ag Cl以下同 ) ,线性范围分别是 2 .0× 1 0 -8～ 2 .0× 1 0 -6mol/l和 1 .0× 1 0 -8～ 5 .0×1 0 -7mol/l,用该法测定水样中锌和锰 ,结果令人满意 .     

石蜡水相氧化及其产物的利用(1)

本文采用水相氧化法对石蜡进行氧化,初步解决了旧氧化工艺中存在的氧化时间长、反应产物复杂、分离困难等一系列问题,文中对石蜡水相氧化的机理,工艺路线、实验条件(温度、压力、催化剂等)进行了讨论,除此之外还对石蜡氧化产物的综合利用进行了广泛的研究,并且已经取得了一定的效果。     

Zn(Ⅱ)、Mn(Ⅱ)竞争结合人血清蛋白研究

用平衡透析法在生理pH值（7．43）条件下，研究了等摩尔比的Zn（Ⅱ）与Mn（Ⅱ）离子竞争结合人血清白蛋白（HSA）。Scatchard图分析表明，Zn（Ⅱ）与Mn（Ⅱ）在HSA中没有共同的强结合位点，在竞争和非竞争结合时，Zn（Ⅱ）的强结合位点数目均为1，Mn（Ⅱ）的强结合位点数目均为2。Hill图分析说明Zn（Ⅱ）与Mn（Ⅱ）之间具有一定的正协同效应。