Jiang-Shan Shen,Jia-Jia Wu,Xiang-Ying Sun,Zhen-Long Wu,Ping Gao,Bin Liu
We found that β-HgS nanocrystals could catalyze the reactions of oxidase substrates such as 3,3′,5,5′-tetramethylbenzidine (TMB) and O-phenylenediamine (OPD) to form coloured and fluorescent products, respectively, but α-HgS nanocrystals could not catalyze these reactions. Further investigation revealed that the predominantly exposed crystal planes may play an important role in determining the catalytic activity. On the basis of these findings, taken together with the reaction of forming a Schiff base between the –NH2 group of OPD and the –CHO group of formaldehyde, a novel, simple, and highly selective photoluminescence (PL) sensing platform for detecting formaldehyde could thereby be successfully developed.
Yang Yang,Rui Huang,Wenqing Xu,Jixiang Zhang,Chaoqun Li,Jianfei Song,Tingyu Zhu
ZnS is a promising sorbent in recovering Hg0 from industrial flue gas due to its excellent Hg0 adsorption capacity. However, the internal structure–activity relationship still needs to be further clarified. In this work, ZnS sorbents with different structures were synthesized with the hydrothermal method by tuning the temperature. The samples had significant differences in the crystallinity, morphology, particle size, and sulfur (S) active sites. The results indicated that Hg0 removal performance was determined by the specific surface area and S active sites. ZnS synthesized at low temperatures (80-ZnS and 120-ZnS) had a larger surface area, while the S sites on the high-temperature-synthesized sample (160-ZnS) were more active for Hg0 adsorption. The 160-ZnS sample exhibited a much higher Hg0 adsorption amount per unit surface area. Further characterization revealed that S22– and Sx were the main active sites for Hg0 adsorption. Sx existed in the form of long-chain polysulfur (L-Sx) on 80-ZnS and 120-ZnS, while it exhibited in the form of short-chain polysulfur (S-Sx) on 160-ZnS. L-Sx had negligible adsorption ability, while S-Sx had a high affinity for Hg0. Hg0 can react with S22– and S-Sx, forming α-HgS and β-HgS, respectively. The new insight in this work can provide theoretical guidance for the design and structure optimization of ZnS, facilitating its practical industrial application.
Zuotai , a famous Tibetan medicinal mixture containing β-HgS, has been used to combine with herbal remedies for treating diseases for more than 1 300 years. The target organ for inorganic mercury toxicity is generally considered to be the kidney. Therefore, it is crucial to reveal the chemical speciation , spatial distribution and potential nephrotoxicity of mercury from Zuotai in kidney. To date, this remains poorly understood. We used X-ray absorption spectroscopy (XAS) and micro X-ray fluorescence (μ-XRF) imaging based on synchrotron radiation to study mercury chemical forms and mercury special distribution in kidney after mice were treated orally with Zuotai , β-HgS or HgCl 2 . Meanwhile, the histopathology of kidney was observed. Mice exposed with Zuotai showed kidney with significant proportion of mercury ions bound to sulfydryl biomolecules (e.g. Cys-S-Hg-S-Cys) plus some of unknown species, but without methylmercury cysteine, which is the same as β-HgS and HgCl 2 . The mercury is mainly deposited in renal cortex in mouse treated with Zuotai , β-HgS or HgCl 2 , but with a low level of mercury in medulla. The total mercury in kidney of mice treated with HgCl 2 was much higher than that of β-HgS, and the later was higher than that of Zuotai . And, HgCl 2 cause severe impairments in mouse kidney, but that was not observed in the Zuotai and β-HgS groups. Meanwhile, the bio-metals (Ca, Zn, Fe and Cu) micro-distributions in kidney were also revealed. These findings elucidated the chemical nature, spatial distribution and toxicity difference of mercury from Zuotai , β-HgS and HgCl 2 in mouse kidney, and provide new insights into the appropriate methods for biological monitoring.
危险品化学品经营许可证（带存储）