CHEMOSPHERE
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2020
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IF 5.778
Lin Dai,Jiaxin Xu,Jinbin Lin,Lingbin Wu,Huahua Cai,Jing Zou,Jun Ma
In this study, iodometric spectrophotometry , the most-used method for detecting peroxydisulfate (PDS), was modified by increasing the concentration of potassium iodide (KI) for realizing the immediate PDS determination and avoiding the interference of hydroxylamine. Kinetic studies showed that the reaction between PDS and I − to generate the yellow-colored I 3 − followed the kinetic equation as - d P D S d t = d I 3 - d t = 1 . 995 × 10 - 2 M - 2 · s - 1 · P D S 1 · I - 2 . Detection time of the iodometric spectrophotometry was shortened from 15 min to 15 s when KI concentration was increased from 0.6 M to 4.8 M. Different with the previous iodometric spectrophotometry, the modified method using 4.8 M KI as the indicator was well tolerable to the interference of hydroxylamine at acidic pH conditions. The calibration curve of the modified method showed a well linear relationship (R 2 = 0.999) between the absorbance of I 3 − at 352 nm and PDS concentration in the range of 0–80 μM. The modified method was highly sensitive with the absorptivity of 2.5 × 10 4 M −1 cm −1 and the limit of detection of 0.11 μM. Moreover, the modified method was successfully applied for monitoring the change of PDS concentration during the degradation of diclofenac with four different PDS-based AOPs , the calculated reaction stoichiometric efficiency ( R S E ( % ) = D i c l o f e n a c d e g r a d e d P D S c o n s u m e d × 100 % ) followed the order as heat/PDS system > hydroxylamine/Fe 2+ /PDS system > hydroxylamine/Cu 2+ /PDS system > Fe 2+ /PDS system.
研究领域:
环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
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2023
·Vol. 52
·期 42
·15484-15488
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IF 4
Xiangyu Zhang,Yunlei Chen,Yongfang Sun,Fei Wang,Xiao-Dong Wen,Tian-Nan Ye
Wide application of novel materials often requires low-cost preparation methods. In this study, we present a simplified and facile preparation method for the [Ca24Al28O64]4+(e−)4 electride material (C12A7:e−). Successful preparation of the C12A7:e− electride was confirmed by XRD patterns and magnetic behavior analysis. The concentration of electrons in the prepared C12A7:e− powder was calculated to be approximately 2.23 × 1021 cm−3, as evaluated by iodometry and TPD. DFT calculations provided insight into the unique electronic structure of C12A7:e−. Additionally, the substitution of the Ca reductant with CaH2 led to a reduction in the solid-state reaction temperature from 1100 to 950 °C, which can be attributed to thermodynamic effects such as a reduction in ΔG°.
研究领域:
材料科学
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化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF FLUORESCENCE
·
2024
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IF 2.6
Ma Xue,Hu Qingqing,Yuan Jingxue,Feng Yao,Cheng Zhengjun
A selective and sensitive fluorescence method for hypochlorite (ClO − ) was designed using glutathione (GSH) modified silicon-doped carbon quantum dots (GSH@Si-CDs). Then a dual emission ratio fluorescence probe (RF-probe) was obtained based on carbodiimide-activated coupling reaction between GSH and Si-CDs. i.e., when the excitation wavelength was kept at 360 nm, the GSH@Si-CDs exhibited strong blue and weak yellow fluorescence at 430 and 580 nm. Meanwhile, the fluorescence of GSH@Si-CDs could be selectively quenched at 430 nm and enhanced at 580 nm in the presence of ClO − , and corresponding limit of detection (LOD) and linear range were measured to be 0.35 µM and 1.0-33.3 µM. The sensing mechanism of the system was also investigated in detail. Moreover, the RF-probe with good accuracy was successfully employed to monitor ClO − in real samples with satisfactory results compared to the standard iodometric method.
研究领域:
分析化学
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材料科学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Arabian Journal of Chemistry
·
2022
·
IF 6.212
Min Liang,Huixia Zhao,Suyi Dai,Chang Yu,Haijun Cheng,Weiguang Li,Fang Lai,Li Ma,Xiongmin Liu
1,3-Butadiene is the simplest conjugated diene, which is widely used in polymer materials, organic synthesis, and other fields. The investigation of its thermal stability and oxidation characteristics is necessary for production, transportation, and use safety. The pressure and temperature behavior of the autoxidation reaction of 1,3-butadiene with oxygen were determined using a custom-designed mini closed pressure vessel test (MCPVT). The effects of free radical initiators CHP and AIBN on the oxidation reaction were investigated. The thermal decomposition characteristics of oxidation products were measured by differential scanning calorimetry (DSC), and its hazards were discussed. The results showed that the oxidation reaction of 1,3-butadiene was easy to occur. Moreover, the activation energies of autoxidation, CHP-initiated oxidation, and AIBN-initiated oxidation reaction were 20.85 kJ·mol −1 , 33.30 kJ·mol −1 , and 56.27 kJ·mol −1 , respectively. In addition, the oxidation products were analyzed by headspace sampler-gas chromatography-mass spectrometry (HS-GC–MS), GC–MS, and iodometry. Some of 1,3-butadiene oxidation products under three conditions are the same, for example, 3-butene-1,2-diol, 4-vinylcyclohexene, 2(5H)-furanone, 2-propen-1-ol, and 2,6-cyclooctadien-1-ol. According to the reaction products, the oxidation reaction pathway of 1,3-butadiene was described. The research results are significant for avoiding fire and explosion accidents in the production, transportation, and application of 1,3-butadiene.
研究领域:
化学工程
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有机化学
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热分析
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安全科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）