JOURNAL OF SEPARATION SCIENCE
·
2016
·Vol. 40
·期 2
·514-523
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IF 2.741
Chaoyi Wang,Pan Zou,Ting Zhang,Haipu Li,Zhaoguang Yang
In this work, an in situ acylation combined with solid-phase microextraction coupled to gas chromatography and mass spectrometry method has been developed for simultaneously determining haloanisoles (2,4,6-trichloranisole, 2,4,6-tribromoanisole), and their direct precursors (2,4,6-trichlorophenol, 2,4,6-tribromophenol) and indirect precursors (2-chloropenol, 2,4-dichlorophenol, 2-bromophenol, 2,4-dibromophenol) in water. The key parameters for the solid-phase microextraction were determined by using Plackett–Burman screening and optimized by central composite optimization. Under optimal conditions, the eight compounds can be analyzed in a short time (33 min) with a strong linearity ranging from 2 to 200 ng/L (correlation coefficient greater than 0.996), showing good sensitivities with the limit of detection in a range of 0.23–0.91 ng/L and a limit of quantification of 0.77–3.03 ng/L, good repeatability (2.00–9.10%) and interday precision (1.67–11.3%). When environmental water samples were treated, the recoveries of target compounds were 75.5–127.3%, suggesting that the developed method could be applied in probing the origin of haloanisoles and monitoring halophenols and haloanisoles in natural waters at concentration levels of ng/L.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2024
·
IF 8.1
Jingyao Wang,Jingqiu Jiang,Hongxia Zhao,Zhansheng Li,Xintong Li,Shafiul Azam,Baocheng Qu
Halobenzoquinones (HBQs) are a novel family of unregulated disinfection byproducts (DBPs). Little is known about their phototransformation activities in natural water. Here, five HBQs with various halogenated substituent types, numbers, and structures positions were selected to investigate the kinetics of degradation in aqueous solutions at various concentrations and in the presence of common environmental variables (Cl − , NO 2 − , and humic acid). The results indicated that dichloride and dibromo-substituted HBQs were photolyzed, whereas tetrachloro-substituted HBQs showed little degradation. The photolysis rate constant ( k ) of HBQs decreased with increasing initial concentration. The presence of NO 2 − and Cl − promoted the degradation of HBQs mainly through the formation of hydroxyl radical (•OH), which were confirmed by electron paramagnetic resonance (EPR). In contrast, humic acid played a negative role on HBQs transformation due to the adsorption and quenching reactions. Possible conversion pathways for HBQs were proposed based on the identification of two major photodegradation products, hydroxylated HBQs and halogenated-benzenetriol, as well as reactive free radicals . This study provided meaningful insights into the environmental fates and risk assessments of HBQs in natural aquatic system.
研究领域:
环境科学
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水处理工程
·
化学动力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
·
2021
·
IF 11.236
Jinxiu Lou,Huijie Lu,Wei Wang,Lizhong Zhu
Halobenzoquinones (HBQs) are emerging disinfection byproducts generated during the reaction of chlorine disinfectant with natural organic matter (NOM) in source water. In this study, the correlations between molecular weight and HBQs generation of river NOM was evaluated. The compositional and functional characteristics of primary HBQs precursors were revealed by using Orbitrap mass spectrometry combined with molecular tagging. The NOM fraction larger than 50 kDa resulted in approximately 9 times more HBQs (50.9 ± 2.7 ng/mgC) than low molecular weight fractions. Significant correlations were found between the yields of HBQs and lignin-like and highly oxygen compounds in NOM, suggesting their critical roles in HBQs formation. Derivatizating the aldehydes, ketones, hydroxyl and carboxyl groups in NOM could reduce HBQs yields by 90.7%–100%. Unraveling the molecular characteristics of HBQs precursors in NOM would greatly benefit the prediction of HBQs yields of different source water, and develop more efficient disinfection byproduct control strategies.
研究领域:
环境科学
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分析化学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Zhourui Xu,Jianjian Wei,Aroob Abid,Zirui Liu,Yasen Wu,Jia Gu,Dehua Ma,Min Zheng
Halobenzoquinones (HBQs) are a class of disinfection byproducts with high cytotoxicity and potential carcinogenicity , which have been widely detected in chlorination of drinking water and swimming pool water. However, to date, the formation of HBQs upon ozonation and the HBQ precursors have been overlooked. This study investigated the formation of chlorinated and dechlorinated HBQs from six dichlorophenol (DCP) isomers. The monomeric and dimeric HBQs were identified in all the ozonation effluents, exhibiting 1–100 times higher toxicity levels than their precursors. The sum of detected HBQs intensity had a satisfactory linear relation with the maximum toxic unit ( R 2 = 0.9657), indicating the primary toxicity contribution to the increased overall toxicity of effluents. Based on density functional theory calculations, when ozone attacks the para carbon to the hydroxyl group of 2,3-DCP, the probability of producing chlorinated HBQs is 80.41 %, indicating that the para carbon attack mainly resulted in the formation of monomeric HBQs. 2,3-dichlorophenoxy radicals were successfully detected in ozonated 2,3-DCP effluent through electron paramagnetic resonance and further validated using theoretical calculation, revealing the formation pathway of dimeric HBQs. The results indicate that chlorinated phenols, regardless of the positions of chlorine substitution, can potentially serve as precursors for both chlorinated and dechlorinated HBQs formation during ozonation.
研究领域:
环境科学
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毒理学
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水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2024
·
IF 5.6
Tao Sun,Yanli Song,YuanYuan Zhang,Mengyi Ba,Wen Li,Zhiqiang Cai,Shaoqiang Hu,Xianming Liu,Shusheng Zhang
Pillar[ n ]arenes (P[ n ]A, n = 5–10) have attracted much attention because of their highly symmetric pillar-shaped architecture with π -electron rich cavity. Nevertheless, the use of ionic liquid functionalized P[ n ]A in chromatography has not been reported up to data. This work reports the investigation of the imidazolium ionic liquids functionalized pillar[6]arene (P6A-C10-IM-C8[NTf 2 ]) as the stationary phase for gas chromatography (GC). The statically coated P6A-C10-IM-C8[NTf 2 ] column (0.25 mm i.d.) showed moderate polarity and high column efficiency of 4733 plates/m determined by n -dodecane at 120 °C ( k = 2.29). Owing to its unique amphiphilic conformation, the P6A-C10-IM-C8[NTf 2 ] showed good column inertness and resolving capability for a wide range of analytes and isomers. Particularly, the P6A-C10-IM-C8[NTf 2 ] column exhibited distinctly advantageous performance for the challenging isomers of halogenated benzenes, benzaldehydes, phenols and anilines over the common commercial columns, namely 5% phenyl methyl polysiloxane (HP-5) and 35% phenyl methyl polysiloxane (HP-35). In addition, it exhibited good column repeatability and reproducibility with RSD values on the retention times less than 0.05% for run-to-run, 0.38% for day-to-day and 2.94% for column-to-column, respectively. This work demonstrates the promising future of ionic liquid P[ n ]A stationary phases for chromatographic separations.
研究领域:
分析化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2024
·
IF 5.6
Tao Sun,Yuanyuan Zhang,Haixin Liu,Xiang Xu,Zhiqiang Cai,Shaoqiang Hu,Xianming Liu,Maurizio Quinto,Shusheng Zhang
Pillar[ n ]arenes (P[ n ]As, n = 5–10), a new generation of macrocyclic hosts, display interesting properties such as 3D π -electron cavity, host-guest interactions, good stability, and easy functionalization, which make these polymers very promising for separation applications. In particular, extended P[ n ]As (EP[ n ]As) show large-sized cavities, structural flexibility, cavity adaptability, and synthetic accessibility. These characteristics have been exploited in this work, which reports for the first time the investigation of two EP[ n ]As (LP6A-C10 and BpP6A-C10) as stationary phases for gas chromatography (GC). LP6A-C10 and BpP6A-C10 columns exhibited moderate polarity (average polarity 117 and 118) and high column efficiencies (3000 plates/m and 3235 plates/m). These columns achieved complete challenging separation of halogenated benzene, benzaldehyde, phenol, and aniline isomers, which are difficult to resolve due to their high resemblance in structures and properties. Experimental results demonstrate the high selectivity and inertness of the prepared columns and their distinct advantages if compared with commercial HP-5 and HP-35 columns. EP[ n ]As columns displayed good separation repeatability with RSD values of 0.01%–0.02 % for run-to-run, 0.01%–0.22 % for day-to-day, and 1.36–3.56 % for column-to-column. This work demonstrates the promising future of EP[ n ]A stationary phases for chromatographic separations.
研究领域:
分析化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 12
·2856
·
IF 4.2
Qin Huang,Hua Zhou,Xianglun Wu,Jiaqi Jiang,Bingdong Zhan,Pinggu Wu
A promising method was established for the determination of nine halobenzoquinones (HBQs) in potable water by membrane solid-phase extraction (MSPE) pretreatment and the liquid chromatography–mass spectrometry (LC-MS) method. A 500 mL water sample was taken for enrichment by the SDB-RPS membrane, which was previously activated by methanol and ultrapure water. The sample was eluted with methanol and re-dissolved with the initial mobile phase after nitrogen blowing. Then, it was detected in negative ion mode using the working curve, and HBQs were quantified by the external standard method. The linearity was satisfactory in the concentration range of 4-1000 ng/L, with correlation coefficients of 0.9963~0.9994. The recoveries were 73.5~126.6% at three spiked levels, with relative standard deviations (RSDs) of 6.8~15.5%. The limits of detection (LOD, S/N = 3) values were 0.1~0.7 ng/L. The results demonstrate that the MSPE-LC-MS method is reliable, rapid, and sensitive for the simultaneous analysis of nine HBPs in potable water.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL RESEARCH
·
2011
·
IF 0.55
Yong-Rui Pi,Jun Tan,Hui Liu,Jie Chen,Zhu-You Qun,Yan-Bo Zeng,Lei Li
Catalytic cracking reaction of 1,2-dimethyl-1,1,2,2-tetrachlorodisilane with a halobenzene (PhCl, PhBr) to prepare methylphenyldichlorosilane has been investigated. Pd(PPh3)4 exhibited the best catalytic activity among the catalysts used. The activity of chlorobenzene was significantly lower than that of bromobenzene. With the latter and toluene as solvent, in the presence of 0.3 mol % Pd(PPh3)4, the conversion of disilane was 100% with a selectivity to MePhSiCl2 of 97.1%.
研究领域:
有机化学
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催化化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 40
·期 11
·9657-9665
·
IF 3.277
Sheng Tang,Qin Bin,Zi-Wei Feng,Wei Chen,Shao-Hua Huang,Zheng-Wu Bai
The goal of the present study is to systematically investigate the enantioseparation performance and eluent tolerance of chiral stationary phases (CSPs) derived from chitosan bis(halophenylcarbamate)-(isobutyrylamide)s. Hence, N-isobutyrylated chitosan was prepared from completely deacetylated chitosan with a high molecular weight. The N-isobutyrylated chitosan was further derivatized with various halo-substituted phenyl isocyanates, consequently affording a series of chitosan bis(halophenylcarbamate)-(isobutyrylamide)s, which were coated onto 3-aminopropyl silica particles to obtain a class of CSPs. The chiral recognition ability of these CSPs was evaluated with nineteen racemates. It was found that the chitosan bis(halophenylcarbamate)-(isobutyrylamide)s showed powerful enantioseparation performance, and those with 4-chlorophenylcarbamate, 3,4-dichlorophenylcarbamate and 4-trifluoromethoxyphenylcarbamate seemed to exhibit comparable or even more superior enantioseparation ability for the tested racemates in comparison with the well-known derivatives of cellulose and amylose. In addition, the dissolvability and swelling of the prepared chitosan bis(halophenylcarbamate)-(isobutyrylamide)s in organic solvents were discussed in particular. The eluent tolerance of the CSP prepared from chitosan bis(3,4-dichlorophenylcarbamate)-(isobutyrylamide), which exhibited relatively more favorable enantioseparation performance among the prepared CSPs, was investigated. It was observed that the tested CSP could be analyzed with 100% ethyl acetate, 100% chloroform and n-hexane/THF (70/30, volume ratio) without a significant loss of recognition and enantioseparation ability. As a consequence, we can safely draw the conclusion that chitosan bis(halophenylcarbamate)-(isobutyrylamide)s prepared from chitosan with a high molecular weight can show good enantioseparation performance as well as satisfactory eluent tolerance.
研究领域:
分析化学
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材料科学
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药物化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Chen Zhong,He Zhao,Hongbin Cao,Ching-Hua Huang
Halobenzoquinones (HBQs), a metabolism of pentachlorophenol, arouse increasing concern for their high toxicity. This paper systematically studied the influences of 31 extracellular nucleophiles on the removal of dichlorobenzoquinones (DCBQs). The results showed that at pH 6.0–8.0, the transformation of DCBQs followed a pattern of pseudo first-order reaction. With the presence of different thiol compound (ratio 1:1), the apparent rate constant of 25DCBQ and 26DCBQ was between 0.028 and 0.204 min −1 and 0.061–0.156 min −1 , respectively, which was 6.6–48.3 times faster than direct hydrolysis and 1.9–23.4 times of that with histidine, a typical amino acid. This was attributed to the different transformation pathways of DCBQs with thiol or amino groups. According to the MS spectrum and transition state theory, thiol compounds was stably incorporated into DCBQs via Michael addition or substitution, which also decreased the oxidative stress of DCBQs by 35.5–86.4% and cytotoxicity of hydrolyzed DCBQ by 44.9–100%, respectively. Conversely, amino acids promoted the hydrolysis of DCBQs by forming unstable AA-DCBQ intermediates that can be further hydrolyzed to OH-DCBQs, leading to an increased selectivity of OH-DCBQs, and increased the oxidative stress of 25DCBQs by 0.2–31.2% and cytotoxicity of hydrolyzed 25DCBQ by 42.0–52.7%. Such difference was inherently related to the nucleophilicity of different atoms. Moreover, it was revealed that the maximum condensed local nucleophilicity index of nucleophiles ( N k, max ) can joint describe the relationship among nucleophilic structures, transformation pathways and toxicity of DCBQs. This paper provided a comprehensive perspective on the fast removal and detoxification of HBQs in extracellular environment.
研究领域:
环境化学
·
毒理学
·
有机化学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2024
·
IF 11.4
Shaoyang Hu,Xiangxiang Li,Falin He,Yuntao Qi,Beibei Zhang,Rutao Liu
Halophenylacetamides (HPAcAms) have been identified as a new group of nitrogenous aromatic disinfection byproducts (DBPs) in drinking water, but the toxicity mechanisms associated with HPAcAms remain almost completely unknown. In this work, the cytotoxicity of HPAcAms in human hepatoma (HepG2) cells was evaluated, intracellular oxidative stress/damage levels were analyzed, their binding interactions with antioxidative enzyme were explored, and a quantitative structure-activity relationship (QSAR) model was established. Results indicated that the EC 50 values of HPAcAms ranged from 2353 μ M to 9780 μ M, and the isomeric structure as well as the type and number of halogen substitutions could obviously induce the change in the cytotoxicity of HPAcAms. Upon exposure to 2-(3,4-dichlorophenyl)acetamide (3,4-DCPAcAm), various important biomarkers linked to oxidative stress and damage, such as reactive oxygen species, 8-hydroxy-2-deoxyguanosine, and cell apoptosis, exhibited a significant increase in a dose-dependent manner. Moreover, 3,4-DCPAcAm could directly bind with Cu/Zn-superoxide dismutase and induce the alterations in their structure and activity, and the formation of complexes was predominantly influenced by the van der Waals force and hydrogen bonding. The QSAR model supported that the nucleophilic reactivity as well as the molecular compactness might be highly important in their cytotoxicity mechanisms in HepG2 cells, and 2-(2,4-dibromophenyl)acetamide and 2-(3,4-dibromophenyl)acetamide deserved particular attention in future studies due to the relatively higher predicted cytotoxicity. This study provided the first comprehensive investigation on the cytotoxicity mechanisms of HPAcAm DBPs.
研究领域:
环境科学
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毒理学
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化学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
Nature Catalysis
·
2021
·Vol. 4
·期 10
·840-849
·
IF 41.813
Guan Qiaoqiao,Zhu Chuwei,Lin Yue,Vovk Evgeny I.,Zhou Xiaohong,Yang Yong,Yu Hancheng,Cao Lina,Wang Hengwei,Zhang Xiaohui,Liu Xinyu,Zhang Mengkai,Wei Shiqiang,Li Wei-Xue,Lu Junling
Particle size governs the geometric and electronic structure of metal nanoparticles (NPs), shaping their catalytic performance. However, size-dependent entanglement in the geometric and electronic structures often leads to a trade-off between activity and selectivity, limiting the optimization of the overall catalytic performance. Here we show that precisely controlled deposition of a platinum monolayer on large gold NPs breaks the activity–selectivity trade-off on particle size in platinum-catalysed chemoselective hydrogenation of halonitrobenzenes, resulting in a remarkable activity, along with a 99% selectivity for haloanilines under mild conditions. The high activity results from upshift of the platinum 5 d -band centre through platinum lattice expansion and ligand effect, whereas the high selectivity is caused by exposing more terrace sites on large particles. The geometric and electronic properties of bimetallic monolayer materials, distinct from monometallic NPs and alloys, constitute a promising platform for the rational design of metal catalysts with superior performance in hydrogenation reactions.
研究领域:
催化
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材料科学
·
化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）