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Chlorination pattern effect on thermodynamic parameters and environmental degradability for C_(10)-SCCPs: Quantum chemical calculation based on virtual combinational library

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Journal of Environmental Sciences 2016年第1期28卷 184-197页

作者： Yuzhen Sun wenxiao pan Yuan Lin Jianjie Fu Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Short-chain chlorinated paraffins（SCCPs） are still controversial candidates for inclusion in the Stockholm *** inherent mixture nature of SCCPs makes it rather difficult to explore their environmental behaviors.A virtual molecule library of 42,720 C10-SCCP congeners covering the full structure spectrum was *** explored the structural effects on the thermodynamic parameters and environmental degradability of C10-SCCPs through semi-empirical quantum chemical *** thermodynamic properties were acquired using the AM1 method,and frontier molecular orbital analysis was carried out to obtain the EHOMO,ELUMO and ELUMO-EHOMO for degradability exploration at the same *** influence of the chlorination degree（NCl on the relative stability and environmental degradation was elucidated.A novel structural descriptor,μ,was proposed to measure the dispersion of the chlorine atoms within a *** were significant correlations between thermodynamic values and NCl,while the reported NCl-dependent pollution profile of C10-SCCPs in environmental samples was basically consistent with the predicted order of formation stability of C10-SCCP *** addition,isomers with largeμ showed higher relative stability than those with small μ.This could be further verified by the relationship between μ and the reactivity of nucleophilic substitution and · OH attack *** C10-SCCP congeners with less Cl substitution and lower dispersion degree are susceptible to environmental degradation via nucleophilic substitution and hydroxyl radical attack,while direct photolysis of C10-SCCP congeners cannot readily occur due to the large ELUMO-EHOMO *** chlorination effect and the conclusions were further checked with appropriate density functional theory（DFT） calculations.

关键词： Short-chain chlorinated paraffins(SCCPs) Virtual combinational library Chlorination degree Chlorination dispersion Thermodynamic properties Environmental degradability

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Conformation preference and related intramolecular noncovalent interaction of selected short chain chlorinated paraffins

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Science China Chemistry 2016年第3期59卷 338-349页

作者： Yuzhen Sun wenxiao pan Jianjie Fu Aiqian Zhang Qinghua Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China Institute of Environment and Health JiangHan UniversityWuhan430056China

Short chain chlorinated paraffins （SCCPs） are not only research focus of environmental issues but also interesting model mol- ecules for organic chemistry which exhibit diverse conformation preference and intramolecular noncovalent interactions （NCIs）. A systematic study was conducted to reveal the conlk）rmation preference and the related intramolecular NCIs in two C^-isomers of SCCPs, 5,5,6,6-tetrachlorodecane and 4,4,6,6-1etrachlorodecane. The overall conformation profile was deter- mined on the basis of relative energies calculated at the MP2/6-311＋＋G（d,p） level with the geometries optimized by B3LYP/6-31 l＋＋G（d,p） method. Then, quantum theory of atoms in molecules （QTAIM） has been adopted to identify the NCls in the selected conformers of the model molecules at both B31~YP/6-31 l＋＋G（d,p） and M06-2X/aug-cc-pvdz level. Different chlorine substitution modes result in varied conformation preference. No obvious gauche effect can be observed tk）r the SCCPs with chlorination on adjacent carbon atoms. The most stable conformer of 5,5,6,6-tetrachlorodecane （tTt） has its three dihedral angles in the T configuration, and there is no intramolecular N（3s found in this molecule. On the contrary, the chlorination on interval carbon atoms favors the adoption of gauche configmation for the H C C CI axis. Not only inlramolecular H-..CI contacts but also H---H interactions have been identified as driving forces to compensate the instability from steric crowding ot the gauche configuration. The gggg and g＇g＇g＇g＇ conformers are the most popular ones, while the populations of tggg and tg＇g＇g＇ conformer are second to those of the gggg and g＇g＇g＇g＇ conformers. Meanwhile, the M06-2X method with large basis sets is preferred for identification of subtle intramolecular NCIs in large molecules like SCCPs.

关键词： short chain chlorinated paraffins intramolecular noncovalent interactions conformation preference chlorination substitution mode

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Theoretical study on the formation mechanism of polychlorinated dibenzothiophenes/thianthrenes from 2-chlorothiophenol molecules

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Journal of Environmental Sciences 2018年第4期30卷 318-327页

作者： Xiaoqing Yu Jiamin Chang Xian Liu wenxiao pan Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

Homogeneous formation of polychlorinated dibenzothiophenes/thianthrenes（PCDT/TAs）,sulfurated compounds analogous to polychlorinated dibenzo-p-dioxin/dibenzofurans（PCDD/Fs）, has been well-documented to occur via radical–radical coupling reactions from chlorinated thiophenol precursors. However, the current understanding of the formation mechanism of PCDT/TAs is exclusively limited to the inherent point of view that chlorothiophenoxy radicals act as the only required intermediates for PCDT/TAs. This study investigates reaction pathways for the formation of PCDT/TAs involving two new types of radical species, i.e., substituted phenyl radicals and substituted thiophenoxyl diradicals. Taking 2-chlorothiophenol（2-CTP） as a model compound for chlorothiophenols,we found that apart from the mostly discussed chlorothiophenoxy radicals, substituted phenyl radicals and substituted thiophenoxyl diradicals could also be readily formed via the reaction of 2-CTP with H radicals. Furthermore, direct self-and cross-coupling of these radicals can result in the formation of PCDT/TAs, including 1-monochlorothianthrene（1-MCTA）, 1,6-dichlorothianthrene（1,6-DCTA）, 4,6-dichlorodibenzothiophene（4,6-DCDT）and 1,6-dichlorodibenzothiophene（1,6-DCDT）. The pathways proposed in this work are proven to be both thermodynamically and kinetically favorable. Particularly, comparisons were made between the formation mechanisms of sulfurated and oxygenated dioxin systems from an energetic point view, showing that replacing oxygen with sulfur atoms greatly reduces the activation barriers of the rate-controlling steps involved in the PCDT/TA formation processes compared with those involved for PCDD/Fs. The calculated results in this work may improve our understanding of the formation mechanism of PCDT/TAs from chlorothiophenol precursors and should be informative to environmental scientists.

关键词： Polychlorinated dibenzothiophenes/thianthrenes Formation mechanism Phenyl radicals Thiophenoxyl diradicals Density functional theory study

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Inhibition of thrombin by functionalized C_(60)nanoparticles revealed via in vitro assays and in silico studies

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Journal of Environmental Sciences 2018年第1期30卷 285-295页

作者： Yanyan Liu Jianjie Fu wenxiao pan Qiao Xue Xian Liu Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Institute of Environment and Health Jianghan UniversityWuhan 430056China

The studies on the human toxicity of nanoparticles（NPs） are far behind the rapid development of engineered functionalized NPs. Fullerene has been widely used as drug carrier skeleton due to its reported low risk. However, different from other kinds of NPs, fullerene-based NPs（C_（60） NPs） have been found to have an anticoagulation effect, although the potential target is still unknown. In the study, both experimental and computational methods were adopted to gain mechanistic insight into the modulation of thrombin activity by nine kinds of C_（60） NPs with diverse surface chemistry properties. In vitro enzyme activity assays showed that all tested surface-modified C_（60） NPs exhibited thrombin inhibition ability. Kinetic studies coupled with competitive testing using 3 known inhibitors indicated that six of the C_（60） NPs, of greater hydrophobicity and hydrogen bond（HB） donor acidity or acceptor basicity, acted as competitive inhibitors of thrombin by directly interacting with the active site of thrombin. A simple quantitative nanostructure-activity relationship model relating the surface substituent properties to the inhibition potential was then established for the six competitive *** docking analysis revealed that the intermolecular HB interactions were important for the specific binding of C_（60） NPs to the active site canyon, while the additional stability provided by the surface groups through van der Waals interaction also play a key role in the thrombin binding affinity of the NPs. Our results suggest that thrombin is a possible target of the surface-functionalized C_（60） NPs relevant to their anticoagulation effect.

关键词： Thrombin C_(60) nanoparticle(NP) Surface modification Activity inhibition Quantitative nanostructure-activity relationship Molecular docking

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Experimental and Theoretical Study on CHF of a Ultra-Supercritical Circulating Fluidized Bed Boiler Water-Wall Tube at near-Critical Pressures

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Journal of Thermal Science 2023年第1期32卷 166-182页

作者： WANG Wenyu MA Zhan QING Hao NIE Chao YANG Haoyu BI Lingfeng YANG Dong pan wenxiao State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China Department of Mechanical Engineering University of Wisconsin-Madison1513 University AveMadisonWI 53706USA

The experimental and theoretical research on the critical heat flux(CHF)in a uniformly heated water-wall tube of the efficient ultra-supercritical circulating fluidized bed(USCFB)boiler has been *** particular,the experimental pressure varies from 18 MPa to 21 MPa,which is from 0.814Pcr–0.95Pcr(Pcr:critical pressure).The mass flux varies from 310 kg·m^(–2)·s^(–1)to 550 kg·m^(–2)·s^(–1).The inlet sub-cooling temperatures vary from 5°C to 10°*** material of the tube is *** experimental investigation,the near critical pressure CHF test data of water are *** find that the CHF mainly occurs when the vapor qualities are less than 0.4,and it occurs earlier(at lower vapor quality)when the pressure is closer to 22.115 MPa or the mass flux is *** the experimental data,a correlation function for the CHF is established via regression and machine *** established via machine learning greatly improved the regression *** study the CHF phenomenon mechanically,a theoretical model is established based on the near-surface bubble crowding model describing the DNB-type *** the development of the CHF model,the friction resistance coefficient is determined according to our test *** comparison with different experimental results,the near-surface bubble crowding model is well suited to describe DNB-type *** calculation results of the model can provide reference for the optimal design of the USCFB boiler.

关键词： circulating fluidized bed critical heat flux near-critical pressure bubble crowding machine learning

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First-principles study on the heterogeneous formation of environmentally persistent free radicals(EPFRs)overα-Fe2O3(0001)surface:Effect of oxygen vacancy

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Journal of Environmental Sciences 2024年第8期142卷 279-289页

作者： wenxiao pan Shuming He Qiao Xue Xian Liu Jianjie Fu Kang Xiao Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310012China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China

Metal oxides with oxygen vacancies have a significant impact on catalytic activity for the transformation of organic pollutants in waste-to-energy(WtE)incineration *** study aims to investigate the influence of hematite surface oxygen point defects on the formation of environmentally persistent free radicals(EPFRs)from phenolic compounds based on the first-principles *** oxygen-deficient conditions were considered:oxygen vacancies at the top surface and on the *** simulations indicate that the adsorption strength of phenol on theα-Fe_(2)O_(3)(0001)surface is enhanced by the presence of oxygen ***,the presence of oxygen vacancies has a negative impact on the dissociation of the phenol molecule,particularly for the surface with a defective point at the top ***-kinetic parameters were established over a temperature range of300-1000 K,and lower reaction rate constants were observed for the scission of phenolic O-H bonds over the oxygen-deficient surfaces compared to the pristine *** negative effects caused by the oxygen-deficient conditions could be attributed to the local reduction of FeⅢto FeⅡ,which lower the oxidizing ability of surface reaction *** findings of this study provide us a promising approach to regulate the formation of EPFRs.

关键词： EPFR formation Phenol dissociation Oxygen-vacancy impact Hematite surface First-principles calculation

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5G无线网络及其关键技术分析

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通信电源技术 2022年第15期39卷 141-142,152页

作者：潘文晓公诚管理咨询有限公司广东广州510000

经济的增长推动了现代通信技术的发展,5G无线网络技术被广泛应用到各个领域,为现代社会更好的发展做出重要贡献。为使5G无线网络发挥出更大的作用,对5G无线网络及其关键技术进行分析研究。对5G网络进行了简单介绍,之后以此为基础分析了5... 详细信息

经济的增长推动了现代通信技术的发展,5G无线网络技术被广泛应用到各个领域,为现代社会更好的发展做出重要贡献。为使5G无线网络发挥出更大的作用,对5G无线网络及其关键技术进行分析研究。对5G网络进行了简单介绍,之后以此为基础分析了5G无线网络中常见的几种关键技术,进而对5G无线技术的规划展开了探讨。

关键词： 5G无线网络关键技术规划

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双酚类化合物的生物代谢机理研究进展

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环境化学 2024年第3期43卷 711-721页

作者：赫淑铭潘文筱刘娴傅建捷张爱茜江桂斌国科大杭州高等研究院环境学院杭州310024 中国科学院生态环境研究中心环境化学与生态毒理学国家重点实验室北京100085 中国科学院大学资源与环境学院北京100049

以双酚A(bisphenol A,简称BPA)及其替代物为代表的双酚类化合物(bisphenols,简称BPs)在各种环境介质、食品、消费品以及人类和动物体中被广泛检出,表明BPs存在全球性大规模污染趋势.除了BPs自身毒性外,其在生物体内的转化代谢产物可能... 详细信息

以双酚A(bisphenol A,简称BPA)及其替代物为代表的双酚类化合物(bisphenols,简称BPs)在各种环境介质、食品、消费品以及人类和动物体中被广泛检出,表明BPs存在全球性大规模污染趋势.除了BPs自身毒性外,其在生物体内的转化代谢产物可能具有比母体化合物更复杂的内分泌干扰效应和毒性效应,对于人体生命健康的影响不容小觑.本文就BPs生物代谢的实验和理论计算研究方法及其取得的研究成果等方面进行回顾总结,在分析现有研究存在的问题和不足上对未来的研究重点提出了展望.

关键词：双酚类化合物代谢转化实验研究理论计算化学研究

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Testing the Coincidence Problem with Strong Gravitational Lens,Type Ia Supernovae and Hubble Parameter Observational Data

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Research in Astronomy and Astrophysics 2022年第11期22卷 214-222页

作者： Jingwang Diao Yu pan wenxiao Xu School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China

In this paper,we use three different kinds of observational data,including 130 strong gravitational lensing(SGL)systems,type Ia supernovae(SNeIa:pantheon and Union2.1)and 31 Hubble parameter data points(H(z))from cosmic chronometers to constrain the phenomenological model(ρ_(x)∝ρ_(m)a^(ξ)).By combining these three kinds of data(Union2.1+SGL+H(z)),we get the parameter value at the confidence interval of 2σ,Ω_(X,0)=0.69±0.34,ω_(x)=−1.24±0.61,ξ=3.8±3.9 and H_(0)=70.22±0.86 kms^(−1) Mpc^(−1).According to our results,we find that theΛCDM model is still the model which is in best agreement with the observational data at present,and the coincidence problem is not *** addition,the Ω_(X) and Ω_(m) have the same order of magnitude in 00.645,it is necessary to introduce the dark energy interacting with dark matter.

关键词： (cosmology:)cosmological parameters (cosmology:)dark energy cosmology:observations

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基于代谢组学分析稻曲病发生对优质水稻稻米品质的影响

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食品科学 2025年第4期46卷 172-179页

作者：潘争艳杨铁鑫解文孝董立强姜秀英马亮李建国白元俊辽宁省水稻研究所辽宁沈阳110101

为研究稻曲病的发生对稻米品质的影响机制,以中感稻曲病的优质粳稻品种辽粳433和辽粳2501为材料,通过非靶向性代谢组学分析,定性到稻米中271种代谢产物,稻曲病的发生诱导稻米中49种代谢产物的相对含量发生显著改变,其中没食子儿茶素、3... 详细信息

为研究稻曲病的发生对稻米品质的影响机制,以中感稻曲病的优质粳稻品种辽粳433和辽粳2501为材料,通过非靶向性代谢组学分析,定性到稻米中271种代谢产物,稻曲病的发生诱导稻米中49种代谢产物的相对含量发生显著改变,其中没食子儿茶素、3-羟基苯甲酸、绿原酸、芥子酸、精胺、α-生育酚、烟酰胺、十二烷酸和棕榈酸的相对含量显著降低,1-单油酸甘油酯、2-单油酸甘油酯、1-单硬脂酸、果糖、赤藓糖、半乳糖、麦芽糖、塔格糖、莽草酸和α-酮戊二酸的相对含量显著上调。这些物质的变化导致稻米中糖酵解、三羧酸循环、脂肪酸合成和次生代谢发生紊乱,增加稻米的垩白粒率或垩白度,降低稻米的整精米率、抗氧化能力和营养价值。

关键词：稻曲病非靶向代谢组学代谢产物稻米品质营养价值

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