1
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Li B, Qu R, Wang T, Guo R, Tian J, Li S, Abukhadra MR, Mahmoud RK, Wang Z. Experimental insights and modeling innovations: Deciphering Fe(VI) oxidation in imidazole ionic liquids through QSAR and RFR. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:134980. [PMID: 38905978 DOI: 10.1016/j.jhazmat.2024.134980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 06/09/2024] [Accepted: 06/18/2024] [Indexed: 06/23/2024]
Abstract
In this investigation, we conducted a detailed analysis of the oxidation of 16 imidazole ionic liquid variants by Fe(VI) under uniform experimental setups, thereby securing a dataset of second-order reaction rate constants (kobs). This methodology ensures superior data consistency and comparability over traditional methods that amalgamate disparate data from varied studies. Utilizing 16 chemical structural parameters obtained via Density Functional Theory (DFT) as descriptors, we developed a Quantitative Structure Activity Relationship (QSAR) model. Through rigorous correlation analysis, Principal Component Analysis (PCA), Multiple Linear Regression (MLR), and Applicability Domain (AD) evaluation, we identified a pronounced negative correlation between the molecular orbital gap energy (Egap) and kobs. MLR analysis further underscored Egap as a pivotal predictive variable, with its lower values indicating heightened oxidative reactivity towards Fe(VI) in the ionic liquids, leading the QSAR model to achieve a predictive accuracy of 0.95. Furthermore, we integrated an advanced machine learning approach - Random Forest Regression (RFR), which adeptly highlighted the critical factors influencing the oxidation efficiency of imidazole ionic liquids by Fe(VI) through elaborate decision trees, feature importance assessment, Recursive Feature Elimination (RFE), and cross-validation strategies. The RFR model demonstrated a remarkable predictive performance of 0.98. Both QSAR and RFR models pinpointed Egap as a key descriptor significantly affecting oxidation efficiency, with the RFR model presenting lower root mean square errors, establishing it as a more reliable predictive tool. The application of the RFR model in this study significantly improved the model's stability and the intuitive display of key influencing factors, introducing promising advanced analytical tools to the field of environmental chemistry.
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Affiliation(s)
- Beibei Li
- College of Environmental Sciences and Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, PR China; State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China
| | - Ruijuan Qu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China
| | - Ting Wang
- College of Environmental Sciences and Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, PR China
| | - Ruixue Guo
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China
| | - Jie Tian
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China
| | - Shuyi Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China
| | | | | | - Zunyao Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing 210023, PR China.
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2
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Bai H, Lu P, Li Y, Wang J, Zhao H. Prediction of phthalate acid esters degradation in soil using QSAR model: A combined consideration of soil properties and quantum chemical parameters. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 226:112830. [PMID: 34592529 DOI: 10.1016/j.ecoenv.2021.112830] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 09/06/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
Phthalic acid esters (PAEs) are predominant hazardous substances and endocrine-disrupting compounds to be controlled in soil. The degradation behaviors of PAEs in soil had been long term concerned. Thus, the degradation rate (K) is important for assessing theexposure risk and is of great significance in evaluating the ecological risk of PAEs in soil environment. But by far, quantitative structure activity relationship (QSAR) models for PAEs degradation have rarely been considered in soil environment. In this study, quantum chemical parameters were considered along with soil properties as two kinds of descriptors in QSAR model. A total of 32 logk of PAEs were collected from reference and experiment. Degradation kinetics in soils were determined by pseudo-first order kinetic models. The residual concentration of PAEs in Udic ferrosols and Aquic cambisols suggesting a potential expose risks of PAEs to ecosystem in soil. The QSAR model between logk and quantum chemical parameters revealed that EHOMO and qC- are two predominant factors in determining logk value. Furthermore,our study further indicated that soil organic matter (SOM) as new predictor contributes more to predict logk values of PAEs during degradation process than pH. Results from this study make a new contribution for methods to predict the degradation of PAEs in soil environment and highlight the potential to evaluate the environmental risks of degradation of PAEs.
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Affiliation(s)
- Hongcheng Bai
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, China; Department of Environmental Science, Chongqing University, China.
| | - Peili Lu
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, China; Department of Environmental Science, Chongqing University, China
| | - Yutong Li
- Chongqing Research Academy of Environmental Sciences, Chongqing 401147, China; Chongqing Engineering & Technology Center of Soil and Groundwater Green & sustainable, China
| | - Jun Wang
- Chongqing Research Academy of Environmental Sciences, Chongqing 401147, China; Chongqing Engineering & Technology Center of Soil and Groundwater Green & sustainable, China
| | - Hanqing Zhao
- State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, China; Department of Environmental Science, Chongqing University, China
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Tan Y, Cheng Z, Liu Y, Gao X, Liu S, Shen Z. Quantum parameter analysis of the adsorption mechanism by freshly formed ferric hydroxide for synthetic dye and antibiotic wastewaters. CHEMOSPHERE 2021; 280:130577. [PMID: 33971408 DOI: 10.1016/j.chemosphere.2021.130577] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 03/24/2021] [Accepted: 04/10/2021] [Indexed: 06/12/2023]
Abstract
In this study, the adsorption effect by freshly formed ferric hydroxide (FFFH) for the removal of 47 synthetic dye and antibiotic wastewaters under different pH conditions (i.e., pH = 4, 7, and 10) was investigated. The average total organic carbon (TOC) removal rates (Rexp) of pollutants under acidic, neutral, and alkaline conditions were 27.10 ± 3.21%, 15.16 ± 2.48%, and 9.72 ± 2.81%, respectively. By analyzing the characteristics of FFFH measured by SEM, XRD, FT-IR, TGA and BET, the properties of pollutants, and the values of Rexp, one can conclude that the large specific surface area and rich hydroxyl groups on the surface of FFFH were the reasons for its adsorption capacity for organic pollutants, and the electrostatic adsorption was the main reason for higher removal rate in acidic condition. Subsequently, to better elucidate the intrinsic factors influencing the removal rates at the molecular structure level, three optimal quantitative structure-activity relationship (QSAR) models were established by using multiple linear regression (MLR) analysis. Results of model validations (e.g., regression coefficient, internal and external verifications, and Y-randomization) showed that the established models exhibited excellent stability, reliability, and robustness with the values of R2 = 0.7544, 0.7764, 0.7528, Q2INT = 0.6451, 0.6836, 0.6228, and Q2EXT = 0.5890, 0.6029, 0.7298 under acidic, neutral, and alkaline conditions, respectively. The results of quantum parameter analysis revealed that the adsorption mechanism of FFFH for dyes and antibiotics mainly includes the activity of adsorption site, the behavior of electron transfer and the strength of molecular polarity.
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Affiliation(s)
- Yujia Tan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Yawei Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Xiaoping Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Shiqiang Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China; Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, PR China.
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4
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Liu J, An F, Li M, Yang L, Wan J, Zhang S. Efficient Degradation of 2,4-Dichlorophenol on Activation of Peroxymonosulfate Mediated by MnO 2. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 107:255-262. [PMID: 33554277 DOI: 10.1007/s00128-021-03109-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 01/08/2021] [Indexed: 06/12/2023]
Abstract
Sulfate radical based-advanced oxidation process has received increasing interest in the remediation of wastewater and contaminated soil. In this study, degradation of 2, 4-dichlorophenol (2, 4-DCP) was investigated over peroxymonosulfate (PMS) activation by MnO2, which was prepared by liquid-phase oxidation method. The prepared MnO2 was characterized by transition electron microscopy, X-ray diffraction, N2 adsorption-desorption, and X-ray photoelectron spectroscopy. Characterization results showed that α-MnO2 exhibited the highest surface area and Mn (III) content. The PMS activation by MnO2 in 2, 4-DCP degradation followed the order of α-MnO2 > γ-MnO2 > β-MnO2, which is dependent on the properties of MnO2 including crystal structure, surface area and Mn (III) content. Influences of initial concentration of 2, 4-DCP, PMS and MnO2 dosage, pH and co-existing inorganic ions on the degradation were examined. Electron paramagnetic resonance (EPR) and quenching experiments with ethanol and tert-butanol suggested that sulfate radicals were the dominant radicals in the process. Findings in this study indicated that α-MnO2 was an attractive catalyst for activation of PMS to degrade 2, 4-DCP in aqueous solution.
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Affiliation(s)
- Jingliang Liu
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China
- School of Environmental Science, Nanjing XiaoZhuang University, Nanjing, 211171, China
| | - Fengxia An
- State Power Environmental Protection Research Institute Co. Ltd., Nanjing, 210031, China
| | - Mei Li
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China
| | - Lu Yang
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China
| | - Jinzhong Wan
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China
| | - Shengtian Zhang
- Ministry of Ecology and Environment of the People's Republic of China, Nanjing Institute of Environmental Sciences, Nanjing, 210042, China.
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5
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Liu Y, Liu S, Cheng Z, Tan Y, Gao X, Shen Z, Yuan T. Predicting the rate constants of volatile organic compounds (VOCs) with ozone reaction at different temperatures. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 273:116502. [PMID: 33486251 DOI: 10.1016/j.envpol.2021.116502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/03/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Based on the bond order, fukui indices and other related descriptors, as well as temperature, a new QSAR model was established to predict the rate constant (kO3) of VOCs degradation by O3. 302 logkO3 values (178-409 K) of 149 VOCs were divided into training set (242 logkO3) and test set (60 logkO3), respectively, which were used to construct and verify the QSAR model. The optimal model (R2 = 0.83, q2 = 0.82, Qext2 = 0.72) shows that EHOMO, BOx and q(C-)n have a greater influence on the value of logkO3. In addition, fukui indices and logkO3 are well correlated. The applicability domains of the current models can be used to predict kO3 of a wide range of VOCs at different temperatures.
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Affiliation(s)
- Yawei Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Shiqiang Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Yujia Tan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Xiaoping Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai, 200240, PR China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China
| | - Tao Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
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6
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Liu Y, Cheng Z, Liu S, Tan Y, Yuan T, Yu X, Shen Z. Quantitative structure activity relationship (QSAR) modelling of the degradability rate constant of volatile organic compounds (VOCs) by OH radicals in atmosphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 729:138871. [PMID: 32361444 DOI: 10.1016/j.scitotenv.2020.138871] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 04/08/2020] [Accepted: 04/19/2020] [Indexed: 06/11/2023]
Abstract
The reaction with hydroxyl radicals (•OH) is an important way to remove the most volatile organic compounds (VOCs) in atmospheric environment. Thus, the reaction rate constant (kOH) is important for assessing the persistence and exposure risk of VOCs, and is of great significance in evaluating the ecological risk of volatile organic chemicals. Fukui indices and bond order have a large effect on the degradation of VOCs, but so far, quantitative structure activity relationship (QSAR) models for VOCs degradation have rarely been considered these two factors. In this study, these two momentous factors will be considered along with other relevant quantitative parameters. A total of 180 substances are divided into training set (144 substances) and test set (36 substances), which are used to build and validate quantitative structure activity relationship (QSAR) models, respectively. Internal, external verification and y-randomization tests showed that the established model had excellent stability and reliability. The energy of the highest occupied molecular orbital (EHOMO), the possibility of being attacked by radicals (f (0)n) and the breaking of chemical bonds (BOx) are the main factors affecting VOCs removal. Finally, the scope of the application domain was determined and the robustness of the model was further verified.
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Affiliation(s)
- Yawei Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Shiqiang Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Yujia Tan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Tao Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China
| | - Xiaodan Yu
- Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, PR China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, PR China; Department of Developmental and Behavioral Pediatrics, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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7
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Cheng Z, Chen Q, Pontius FW, Gao X, Tan Y, Ma Y, Shen Z. Two new predictors combined with quantum chemical parameters for the selection of oxidants and degradation of organic contaminants: A QSAR modeling study. CHEMOSPHERE 2020; 240:124928. [PMID: 31563101 DOI: 10.1016/j.chemosphere.2019.124928] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 09/03/2019] [Accepted: 09/20/2019] [Indexed: 06/10/2023]
Abstract
Oxidation is an attractive treatment method to effectively remove organic contaminants in water. In this study, degradation of 30 organic compounds in different oxidation systems was evaluated, including oxygen (O2), hydrogen peroxide (H2O2), ozone (O3) and hydroxyl radical (HO). First, a quantitative structure-activity relationship (QSAR) model for oxidation-reduction potentials (ORPs) of organics was developed and exhibited a good performance to predict ORP values of organics with evaluation indices of squared correlation coefficient (R2) = 0.866, internal validation (q2) = 0.811 and external validation (Qext2) = 0.669. Four quantum parameters, including f(+)n, f(-)n, EHOMO and EB3LYP dominate the ORP values. Subsequently, a relationship between reaction rates (k) and the difference of ORP for oxidants and organics (ΔEoxi-org) was established, however, which was limited (R2= 0.697). Therefore, two new predictors (slopes and intercepts) are proposed based on the linear relationships between k values and ORPs of oxidants. These new predictors can be applied to estimate the reaction rates and minimum oxidation potential for organic compounds. Afterwards, to express the two predictors, QSAR models were established. The two optimal QSAR models fitted very well with experimental values and were demonstrated to be stable and accurate based on R2 (0.982 and 0.965), q2 (0.950 and 0.950) and Qext2 (0.985 and 0.989). BOx, q(H)+ and q(C)x were main factors influencing the slopes and intercepts. This study developed methods to predict ORPs of organics and established two new predictors to estimate the reaction rates undergoing different oxidation processes, offering new insights into the oxidant selection.
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Affiliation(s)
- Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Qincheng Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Frederick W Pontius
- Department of Civil Engineering and Construction Management, Gordon and Jill Bourns College of Engineering, California Baptist University, Riverside, CA, 92507, USA
| | - Xiaoping Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Yujia Tan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Yuning Ma
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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Hou J, Tang J, Chen J, Zhang Q. Quantitative Structure-Toxicity Relationship analysis of combined toxic effects of lignocellulose-derived inhibitors on bioethanol production. BIORESOURCE TECHNOLOGY 2019; 289:121724. [PMID: 31271911 DOI: 10.1016/j.biortech.2019.121724] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
This study performed a Quantitative Structure-Toxicity Relationship (QSTR) model to evaluate the combined toxicity of lignocellulose-derived inhibitors on bioethanol production. Compared with all the control groups, the combined systems exhibited lower conductivity values, higher oxidation-reduction potential values, as well as maximum inhibition rates. These results indicated that the presence of combined inhibitors had a negative effect on the bioethanol fermentation process. Meanwhile, QSTR model was excellent for evaluating the combined toxic effects at lower ferulic acid concentration (([1:4] × IC50)) and (([1:1] × IC50)), due to higher R2 values (0.994 and 0.762), lower P values (0.000 and 0.023) and relative error values (less than 30%). The obtained results also showed that the combined toxic effects of ferulic acid and representative lignocellulose-derived inhibitors were relevant to different molecular descriptors. Meanwhile, the interactions of combined inhibitors were weaker when ferulic acid was at low concentration ([1:4] × IC50).
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Affiliation(s)
- Jinju Hou
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China
| | - Jiawen Tang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China; Institute of Eco-Chongming (IEC), 3663 N. Zhongshan Rd., Shanghai 200062, China
| | - Jinhuan Chen
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China; Institute of Eco-Chongming (IEC), 3663 N. Zhongshan Rd., Shanghai 200062, China
| | - Qiuzhuo Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 200241 Shanghai, China; Institute of Eco-Chongming (IEC), 3663 N. Zhongshan Rd., Shanghai 200062, China.
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Asghar A, Bello MM, Raman AAA, Daud WMAW, Ramalingam A, Zain SBM. Predicting the degradation potential of Acid blue 113 by different oxidants using quantum chemical analysis. Heliyon 2019; 5:e02396. [PMID: 31517121 PMCID: PMC6734339 DOI: 10.1016/j.heliyon.2019.e02396] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/22/2019] [Accepted: 08/28/2019] [Indexed: 12/03/2022] Open
Abstract
In this work, quantum chemical analysis was used to predict the degradation potential of a recalcitrant dye, Acid blue 113, by hydrogen peroxide, ozone, hydroxyl radical and sulfate radical. Geometry optimization and frequency calculations were performed at ‘Hartree Fock’, ‘Becke, 3-parameter, Lee–Yang–Parr’ and ‘Modified Perdew-Wang exchange combined with PW91 correlation’ levels of study using 6-31G* and 6-31G** basis sets. The Fourier Transform-Raman spectra of Acid blue 113 were recorded and a complete analysis on vibrational assignment and fundamental modes of model compound was performed. Natural bond orbital analysis revealed that Acid blue 113 has a highly stable structure due to strong intermolecular and intra-molecular interactions. Mulliken charge distribution and molecular electrostatic potential map of the dye also showed a strong influence of functional groups on the neighboring atoms. Subsequently, the reactivity of the dye towards the oxidants was compared based on the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy values. The results showed that Acid blue 113 with a HOMO value -5.227 eV exhibits a nucleophilic characteristic, with a high propensity to be degraded by ozone and hydroxyl radical due to their lower HOMO-LUMO energy gaps of 4.99 and 4.22 eV respectively. On the other hand, sulfate radical and hydrogen peroxide exhibit higher HOMO-LUMO energy gaps of 7.92 eV and 8.10 eV respectively, indicating their lower reactivity towards Acid blue 113. We conclude that oxidation processes based on hydroxyl radical and ozone would offer a more viable option for the degradation of Acid blue 113. This study shows that quantum chemical analysis can assist in selecting appropriate advanced oxidation processes for the treatment of textile effluent.
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Affiliation(s)
- Anam Asghar
- Department of Chemical Engineering, University of Engineering & Technology, G.T. Road, Lahore, 54890, Pakistan
| | - Mustapha Mohammed Bello
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Abdul Aziz Abdul Raman
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Wan Mohd Ashri Wan Daud
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, 50603, Malaysia
| | - Anantharaj Ramalingam
- Department of Chemical Engineering, SSN College of Engineering, Chennai, Tamil Nadu, 603110, India
| | - Sharifuddin Bin Md Zain
- Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia
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Cheng J, Zhu K, Lu H, Yue H, Liu C, Liang B, Tang S. Quantitative Relationship between CO2 Absorption Capacity and Amine Water System: DFT, Statistical, and Experimental Study. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b01297] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jingxing Cheng
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Kun Zhu
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
- Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China
| | - Houfang Lu
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
- Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China
| | - Hairong Yue
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
- Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China
| | - Changjun Liu
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
| | - Bin Liang
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
- Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu 610207, China
| | - Siyang Tang
- Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China
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11
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Evaluation of inhibition of lignocellulose-derived by-products on bioethanol production by using the QSAR method and mechanism study. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.04.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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12
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Ma Y, Ma K, Wang H, Geng X, Gao J, Zhu Z, Wang Y. QSPR modeling of azeotropic temperatures and compositions for binary azeotropes containing lower alcohols using a genetic function approximation. Chin J Chem Eng 2019. [DOI: 10.1016/j.cjche.2018.06.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Decomposition of 14 organophosphate flame retardants during supercritical water oxidation. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2018.09.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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14
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Chu YB, Li M, Liu JW, Xu W, Cheng SH, Zhao HZ. Molecular insights into the mechanism and the efficiency-structure relationship of phosphorus removal by coagulation. WATER RESEARCH 2018; 147:195-203. [PMID: 30312792 DOI: 10.1016/j.watres.2018.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/07/2018] [Accepted: 10/02/2018] [Indexed: 06/08/2023]
Abstract
Types and structures of phosphorus compounds influence the removal of phosphorus by coagulation. Until now, the molecular-level interaction between coagulants and phosphorus (especially organophosphates) and the relationship between removal efficiency and phosphorus structure have not been clear. This work investigated the removal of phosphorus with different structures using conventional coagulants (poly aluminum chloride (PACl) and polymerized ferric sulfate (PFS)) and a novel covalently-bound inorganic-organic hybrid coagulant (CBHyC). CBHyC removed more than 98% of phosphate and most of organophosphates, had more stable performance than PACl and PFS, and was less affected by pH, initial phosphorus concentration, and co-occurring materials. Molecular dynamics simulation demonstrated that CBHyC removed phosphorus mainly through electrostatic attraction and hydrophobic interaction. Furthermore, this work established QSAR (quantitative structure activity relationship) models for removal efficiency and organophosphate structure for the first time. The model showed that atomic charges of phosphorus atoms (QP) and hydrogen atoms (QH+) in the system and the energy gap (ΔEMO) affected electronegativity and hydrophobicity, thus influencing organophosphate removal efficiency. The model had high fitting precision and good predictive ability and has the potential to greatly reduce the cost of optimizing processes and conditions for phosphorus removal.
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Affiliation(s)
- Yong-Bao Chu
- Department of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, People's Republic of China
| | - Min Li
- Department of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao, 266042, People's Republic of China
| | - Jin-Wei Liu
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Wei Xu
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Shi-Han Cheng
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China
| | - Hua-Zhang Zhao
- Department of Environmental Engineering, Peking University, Beijing, 100871, People's Republic of China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, People's Republic of China.
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15
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Yang B, Cheng Z, Yuan T, Gao X, Tan Y, Ma Y, Shen Z. Temperature sensitivity of nitrogen-containing compounds decomposition during supercritical water oxidation (SCWO). J Taiwan Inst Chem Eng 2018. [DOI: 10.1016/j.jtice.2018.07.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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16
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Cheng Z, Yang B, Chen Q, Tan Y, Gao X, Yuan T, Shen Z. 2D-QSAR and 3D-QSAR simulations for the reaction rate constants of organic compounds in ozone-hydrogen peroxide oxidation. CHEMOSPHERE 2018; 212:828-836. [PMID: 30193231 DOI: 10.1016/j.chemosphere.2018.08.097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 08/14/2018] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
Synergistic oxidation of ozone (O3) and hydrogen peroxide (H2O2) is an effective water treatment for the elimination of organic pollutants. In this study, 23 organic compounds were conducted to study the reaction rate constants during O3-H2O2 oxidation. Then, two- and three-dimensional quantitative structure-activity relationship (QSAR) models were established to investigate the factors influencing the reaction rate constants by using multiple linear regression method and comparative molecular similarity index analysis (CoMSIA) method, respectively. Both of the two models showed good performance on predicting the reaction rate constants, the associated statistical indices of 2D-QSAR and 3D-QSAR models were R2 = 0.898 and 0.952, q2 = 0.841 and 0.951, Qext2 = 0.968 and 0.970, respectively. But varied in the influence factors, as for the 2D-QSAR model, three quantum chemical parameters, included dipole moment, the largest change of charge in each atom during the nucleophilic attack, the maximum positive partial charge on a hydrogen atom linked with a carbon atom affected the reaction rate. While in the 3D-QSAR model, the electrostatic field played the most important role in evaluating the reaction rate with the contribution of 35.8%, followed by hydrogen bond acceptor and hydrophobic fields with the contribution of 24.9% and 23.2%, respectively. These two models provided predictive tools to study the influencing factors for the degradation of organics and might potentially be applied for estimating the removal properties of unknown organics in O3-H2O2 oxidation process.
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Affiliation(s)
- Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Bowen Yang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Qincheng Chen
- School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Yujia Tan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Xiaoping Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Tao Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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17
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Yang B, Cheng Z, Tang Q, Shen Z. Nitrogen transformation of 41 organic compounds during SCWO: A study on TN degradation rate, N-containing species distribution and molecular characteristics. WATER RESEARCH 2018; 140:167-180. [PMID: 29709766 DOI: 10.1016/j.watres.2017.12.080] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 12/25/2017] [Accepted: 12/30/2017] [Indexed: 06/08/2023]
Abstract
Supercritical water oxidation (SCWO) of 41 N-containing compounds was examined under a stable temperature and pressure of 450 °C and 24 MPa, respectively, reaction time ranged from 0.5 to 6 min with 500% excess oxygen, resulted in the degradation rate constants of total organic carbon (kTOC) and total nitrogen (kTN) were 0.162-3.693 and 0.065-0.416 min-1, respectively. The N-containing products were primary N2, ammonium and nitrate. As for amino-group compounds, the main product was ammonia, while for nitro-group compounds, nitrate was the predominant. In terms of diazo and N-heterocyclic group compounds, the main products generally were nitrate and ammonium, respectively. Interestingly, 2-, 3- and 4-nitroaniline, containing both of nitro and amino group, would directly decompose into N2. The reaction pathways of acid orange 74 was proposed based on Fukui indices, which generally included denitrification, ring-open and mineralization. Density functional theory (DFT) method was applied to calculate the quantum properties of the 41 N-containing compounds in order to further examine the relationship between TN removal and molecular structural characteristics. The correlation result showed that among all the 17 molecular characteristics, F(+)n, F(-)n, F(0)n, and EHOMO achieved high correlation coefficients.
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Affiliation(s)
- Bowen Yang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Qingli Tang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
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18
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Yang B, Cheng Z, Fan M, Jia J, Yuan T, Shen Z. Supercritical water oxidation of 2-, 3- and 4-nitroaniline: A study on nitrogen transformation mechanism. CHEMOSPHERE 2018; 205:426-432. [PMID: 29704850 DOI: 10.1016/j.chemosphere.2018.04.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 02/03/2018] [Accepted: 04/05/2018] [Indexed: 05/16/2023]
Abstract
Supercritical water oxidation (SCWO) of 2-, 3- and 4-nitroaniline (NA) was investigated under residence time of 1-6 min, pressure of 18-26 MPa, temperature of 350-500 °C, with initial concentration of 1 mM and 300% excess oxygen. Among these operating conditions, temperature and residence time played a more significant role in decomposing TOC and TN than pressure. Moreover, the products of N-containing species were mainly N2, ammonia and nitrate. When temperature, pressure and retention time enhanced, the yields of NO3- and org-N were reduced, the amount of N2 was increasing, the proportion of NH4+, however, presented a general trend from rise to decline in general. The experiment of aniline/nitrobenzene indicated that TN removal behavior between amino and nitro groups would prefer to happen in the molecule rather than between the molecules, therefore, the smaller interval between the amino and nitro group was the more easily to interreact. This might explain the reason why TN removal efficiency was in an order that 2-NA > 3-NA > 4-NA. The NH4+/NO3- experiment result demonstrated that ammonia and nitrate did convert into N2 during SCWO, however, the formation of N2 was little without auxiliary fuel. Density functional theory (DFT) method was used to calculate the molecular structures of 2-, 3- and 4-NA to further explore reaction mechanism, which verified that amino group was more easily to be attacked than nitro group. Based on these results, the conceivable reaction pathways of 2-, 3- and 4-NA were proposed, which contained three parts, namely denitrification, ring-open and mineralization.
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Affiliation(s)
- Bowen Yang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhiwen Cheng
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Maohong Fan
- Department of Chemical and Petroleum Engineering, University of Wyoming, Laramie, WY 82071, USA; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Jinping Jia
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Tao Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Wang J, Dong S, Yu C, Han X, Guo J, Sun J. An efficient MoO3 catalyst for in-practical degradation of dye wastewater under room conditions. CATAL COMMUN 2017. [DOI: 10.1016/j.catcom.2017.01.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022] Open
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20
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Hou B, Ren B, Deng R, Zhu G, Wang Z, Li Z. Three-dimensional electro-Fenton oxidation of N-heterocyclic compounds with a novel catalytic particle electrode: high activity, wide pH range and catalytic mechanism. RSC Adv 2017. [DOI: 10.1039/c7ra00361g] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel three-dimensional (3D) heterogeneous electro-Fenton (EF) system with sludge deserved activated carbon from sewage and iron sludge (SAC-Fe) as catalytic particle electrodes (CPEs) was constructed in this study.
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Affiliation(s)
- Baolin Hou
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
| | - Bozhi Ren
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
| | - Renjian Deng
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
| | - Guocheng Zhu
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
| | - Zhenghua Wang
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
| | - Zhi Li
- Hunan Provincial Key Laboratory of Shale Gas Resource Utilization
- School of Civil Engineering
- Hunan University of Science and Technology
- Xiangtan 411201
- China
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21
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Multiple Linear Regressions by Maximizing the Likelihood under Assumption of Generalized Gauss-Laplace Distribution of the Error. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2016; 2016:8578156. [PMID: 28090215 PMCID: PMC5174750 DOI: 10.1155/2016/8578156] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 10/23/2016] [Indexed: 11/17/2022]
Abstract
Multiple linear regression analysis is widely used to link an outcome with predictors for better understanding of the behaviour of the outcome of interest. Usually, under the assumption that the errors follow a normal distribution, the coefficients of the model are estimated by minimizing the sum of squared deviations. A new approach based on maximum likelihood estimation is proposed for finding the coefficients on linear models with two predictors without any constrictive assumptions on the distribution of the errors. The algorithm was developed, implemented, and tested as proof-of-concept using fourteen sets of compounds by investigating the link between activity/property (as outcome) and structural feature information incorporated by molecular descriptors (as predictors). The results on real data demonstrated that in all investigated cases the power of the error is significantly different by the convenient value of two when the Gauss-Laplace distribution was used to relax the constrictive assumption of the normal distribution of the error. Therefore, the Gauss-Laplace distribution of the error could not be rejected while the hypothesis that the power of the error from Gauss-Laplace distribution is normal distributed also failed to be rejected.
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22
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Quantitative Structure Activity Relationship Models for the Antioxidant Activity of Polysaccharides. PLoS One 2016; 11:e0163536. [PMID: 27685320 PMCID: PMC5042491 DOI: 10.1371/journal.pone.0163536] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 09/10/2016] [Indexed: 01/06/2023] Open
Abstract
In this study, quantitative structure activity relationship (QSAR) models for the antioxidant activity of polysaccharides were developed with 50% effective concentration (EC50) as the dependent variable. To establish optimum QSAR models, multiple linear regressions (MLR), support vector machines (SVM) and artificial neural networks (ANN) were used, and 11 molecular descriptors were selected. The optimum QSAR model for predicting EC50 of DPPH-scavenging activity consisted of four major descriptors. MLR model gave EC50 = 0.033Ara-0.041GalA-0.03GlcA-0.025PC+0.484, and MLR fitted the training set with R = 0.807. ANN model gave the improvement of training set (R = 0.96, RMSE = 0.018) and test set (R = 0.933, RMSE = 0.055) which indicated that it was more accurately than SVM and MLR models for predicting the DPPH-scavenging activity of polysaccharides. 67 compounds were used for predicting EC50 of the hydroxyl radicals scavenging activity of polysaccharides. MLR model gave EC50 = 0.12PC+0.083Fuc+0.013Rha-0.02UA+0.372. A comparison of results from models indicated that ANN model (R = 0.944, RMSE = 0.119) was also the best one for predicting the hydroxyl radicals scavenging activity of polysaccharides. MLR and ANN models showed that Ara and GalA appeared critical in determining EC50 of DPPH-scavenging activity, and Fuc, Rha, uronic acid and protein content had a great effect on the hydroxyl radicals scavenging activity of polysaccharides. The antioxidant activity of polysaccharide usually was high in MW range of 4000-100000, and the antioxidant activity could be affected simultaneously by other polysaccharide properties, such as uronic acid and Ara.
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23
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Gonfa G, Bustam MA, Shariff AM, Muhammad N, Ullah S. Quantitative structure–activity relationships (QSARs) for estimation of activity coefficient at infinite dilution of water in ionic liquids for natural gas dehydration. J Taiwan Inst Chem Eng 2016. [DOI: 10.1016/j.jtice.2016.06.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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24
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Jia L, Shen Z, Su P. Relationship between reaction rate constants of organic pollutants and their molecular descriptors during Fenton oxidation and in situ formed ferric-oxyhydroxides. J Environ Sci (China) 2016; 43:257-264. [PMID: 27155432 DOI: 10.1016/j.jes.2015.10.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 10/15/2015] [Accepted: 10/15/2015] [Indexed: 06/05/2023]
Abstract
Fenton oxidation is a promising water treatment method to degrade organic pollutants. In this study, 30 different organic compounds were selected and their reaction rate constants (k) were determined for the Fenton oxidation process. Gaussian09 and Material Studio software sets were used to carry out calculations and obtain values of 10 different molecular descriptors for each studied compound. Ferric-oxyhydroxide coagulation experiments were conducted to determine the coagulation percentage. Based upon the adsorption capacity, all of the investigated organic compounds were divided into two groups (Group A and Group B). The percentage adsorption of organic compounds in Group A was less than 15% (wt./wt.) and that in the Group B was higher than 15% (wt./wt.). For Group A, removal of the compounds by oxidation was the dominant process while for Group B, removal by both oxidation and coagulation (as a synergistic process) took place. Results showed that the relationship between the rate constants (k values) and the molecular descriptors of Group A was more pronounced than for Group B compounds. For the oxidation-dominated process, EHOMO and Fukui indices (f(0)x, f(-)x, f(+)x) were the most significant factors. The influence of bond order was more significant for the synergistic process of oxidation and coagulation than for the oxidation-dominated process. The influences of all other molecular descriptors on the synergistic process were weaker than on the oxidation-dominated process.
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Affiliation(s)
- Lijuan Jia
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Bioassay and Safety Assessment Laboratory, Shanghai Academy of Public Measurement, Shanghai 201203, China
| | - Zhemin Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Pingru Su
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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