共查询到18条相似文献,搜索用时 62 毫秒
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碘量法测定锑配合物中锑含量的研究 总被引:6,自引:0,他引:6
采用碘标准溶液直接滴定测定锑配合物中锑含量 ,以盐酸和酒石酸钾钠溶解样品 ,以淀粉作指示剂 ,并讨论了相关因素对测定的影响。该方法简便、准确、快速、重现性好 ,用于配合物中锑的测定取得了满意的结果。其变异系数 <0 3% ,相对误差 <0 2 % 相似文献
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目的:探索水溶性槲皮素衍生物合成方法。方法:通过酯基引入、酯水解、酸化三步合成水溶性槲皮素衍生物。结果:通过新的合成路线合成了鲜见报道的化合物。结论:在保留其生物活性的前提下,在槲皮素7-位引入羧甲基,可以制备水溶性羧甲基槲皮素钠盐。 相似文献
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以槲皮素为原料、浓硫酸作催化剂,85℃与苯甲酰氯反应,TLC板监测反应完毕,过滤、氯仿/甲醇重结晶合成标题化合物。UV表征显示,槲皮素的两个特征吸收峰均发生蓝移,这是形成新化合物共轭体系引起的。IR中ν—OH峰明显减弱,说明槲皮素的5个羟基中有的羟基发生了反应;νCO位于1 745.32 cm-1,酯羰基峰明显增强;νC—O位于1 259.66cm-1,峰变宽增强。1HNMR中3-OH、3'-OH、4'-OH上面的氢消失,说明与苯甲酰氯发生了酯化反应;同时,在δ6.7~8.4处有苯甲酰基的多重峰。MS中m/z 615.2为槲皮素三苯甲酸酯的分子离子峰。因此,槲皮素与苯甲酰氯反应可以得到标题化合物。 相似文献
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He Li Yue Fei Shuwen Xue Gege Zhang Ziqi Bian Fanfan Guo Li Wang Ruiqing Chai Shuqi Zhang Zhenyu Cui Shiwei Wang Jun Zhang 《International journal of molecular sciences》2022,23(3)
Antimony (Sb), a global and priority controlled pollutant, causes severe environmental issues. Bioremediation by microbial communities containing sulfate-reducing bacteria (SRB) is considered to be among the safest, economical, and environmentally friendly methods to remove Sb from wastewater. However, the roles of SRB species in these communities remain uncertain, and pure cultures of bacteria that may be highly efficient have not yet been developed for Sb removal. In this study, an Sb tolerant community was enriched from municipal sludge, and molecular ecological analysis showed that Escherichia (40%) and Desulfovibrio (15%) were the dominant bacteria. Further isolation and identification showed that the enriched SRB strains were closely related to Cupidesulfovibrio oxamicus, based on the molecular analyses of 16S rRNA and dsrB genes. Among them, a strain named SRB49 exhibited the highest activity in removal of Sb(V). SRB49 was able to remove 95% of Sb(V) at a concentration of 100 mg/L within 48 h under optimum conditions: a temperature of 37–40 °C, an initial pH value of 8, 4 mM of sulfate, and an initial redox potential of 145–229 mV. SEM-EDX analysis showed that SRB49 did not adsorb Sb(V) but reduced and precipitated Sb(V) via the formation of Sb2S3. The results demonstrated the potential roles that pure cultures of SRB species may play in Sb removal and the use of Sb-tolerant SRB strains for Sb remediation. 相似文献