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Science China Chemistry 2014年第7期57卷 1048-1052页

作者： LIU LiJun CHEN JiZhong CHEN WenDuo LI LiangYi AN LiJia State key laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The diffusion behavior of polyelectrolytes in dilute salt-free solution is studied through a hybrid mesoscale simulation technique that combines the molecular dynamics method and the multiparticle collision dynamics *** elucidate the effects of hydrodynamic interactions(HI),we compare results for hydrodynamic and random *** HI are taken into account,we find that the chain diffusivity decreases initially and then increases gradually with the increasing strength of the Coulomb *** contrast,when HI are switched off,the electrostatic-dependent diffusivity shows three distinct regions,and a plateau of approximately constant diffusivity manifests between two decreasing *** findings reveal that the dynamics of polyelectrolytes in dilute solution depend on the coupling effects of hydrodynamic and Coulomb interactions,and that these dynamics can be understood by considering the conformational changes of chains,the counterion condensation,and the dynamics of counterions.

关键词： polyelectrolytes diffusion coefficient hydrodynamic interactions Coulomb interactions Bjerrum length

Finite-time asynchronous dissipative filtering of conic-type nonlinear Markov jump systems

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Science China(Information Sciences) 2021年第5期64卷 151-162页

作者： Xiang ZHANG Shuping HE Vladimir STOJANOVIC Xiaoli LUAN Fei LIU key laboratory of Intelligent Computing and Signal Processing (Ministry of Education) School of Electrical Engineering and Automation Anhui University Department of Automatic Control Robotics and Fluid Technique Faculty of Mechanical and Civil EngineeringUniversity of Kragujevac key laboratory of Advanced Process Control for Light Industry (Ministry of Education) Institute of AutomationJiangnan University

In the present study, the finite-time asynchronous dissipative filter design problem for the Markov jump systems with conic-type nonlinearity is studied. The hidden Markov model can describe the asynchronism embodied in the system modes and the filter modes reasonably. Moreover, a suitable LyapunovKrasovskii function is utilized and linear matrix inequalities are applied to obtain adequate conditions. These techniques guarantee the finite-time boundedness and strict dissipativity of the filtering error dynamic system. Furthermore, the design problems of the passive filter and the H∞ filter are studied by adjusting the three parameters U, G and V. Finally, the filter gains and the optimal index α*are obtained and the correctness and feasibility of the designed approach are verified by a simulation example.

关键词： dissipative filtering hidden Markov model finite-time boundedness Markov jump systems conic-type nonlinearity

Species,engineering and characterizations of defects in TiO2-basedphotocatalyst

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Chinese Chemical Letters 2018年第5期29卷 671-680页

作者： Beibei Dong Taifeng Liu Can Li Fuxiang Zhang State key laboratory of Catalysis 2011-iChEM Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Dalian 116023 China University of Chinese Academy of Sciences Beijing 100049 China National & Local Joint Engineering Research Center for applied Technology of Hybrid Nanomaterials Collaborative Innovation Center of Nano FunctionalMaterials and Applications of Henan Province Henan University Kaifeng 475004 China

Light absorption, charge separation and surface reaction are considered as the main processes ofphotocatalysis on one semiconductor, and all of them are demonstrated to be related to the defect statesof photocatalysts. This paper will choose Ti02 as model photocatalyst to introduce some basic conceptsand strategies related to defects and methods developed to characterize defects in the past ***, such strategies as hydrogenation and metal/nonmetal doping intoTi02 will be introduced toextend utilization of solar spectrum and/or to provide active sites. On the contrary, the unfavorable effectof defects such as acting as recombination centers of photogenerated carriers will also be *** typical methods to characterize the properties of defects are summarized, which contain electronparamagnetic resonance （EPR）, photoluminescence technique （PL）, positron annihilation spectroscopy（PAS）, and so on. We do hope that this review will make a revealing effect on understanding to thefunctions of defects as well as construction of efficient photocatalytic systems in the future.

关键词： Titanium dioxide Defect engineering Photocatalysis Water splitting Environmental purification

Abundance of antibiotic resistance genes and their association with bacterial communities in activated sludge of wastewater treatment plants: Geographical distribution and network analysis

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Journal of Environmental Sciences 2019年第8期31卷 24-38页

作者： Haihan Zhang Huiyan He Shengnan Chen Tinglin Huang Kuanyu Lu Zhonghui Zhang Rong Wang Xueyao Zhang Hailong Li key laboratory of Northwest Resource Environment and Ecology MOE Xi'an University of Architecture and Technology Shaanxi key laboratory of Environmental Engineering Xi'an University of Architecture and Technology Xi'an Environmental Monitoring Center Research Institute of applied Biology Shanxi University

Wastewater treatment plants(WWTPs) are deemed reservoirs of antibiotic resistance genes(ARGs). Bacterial phylogeny can shape the resistome in activated sludge. However, the co-occurrence and interaction of ARGs abundance and bacterial communities in different WWTPs located at continental scales are still not comprehensively understood. Here, we applied quantitative PCR and Miseq sequence approaches to unveil the changing profiles of ARGs(sul1, sul2, tet W, tet Q, tet X), int I1 gene, and bacterial communities in 18 geographically distributed WWTPs. The results showed that the average relative abundance of sul1 and sul2 genes were 2.08 × 10^(-1) and 1.32 × 10^(-1) copies/16 S rRNA copies, respectively. The abundance of tet W gene was positively correlated with the Shannon diversity index(H′), while both studied sul genes had significant positive relationship with the int I1 gene. The highest average relative abundances of sul1, sul2, tet X, and int I1 genes were found in south region and oxidation ditch system. Network analysis found that 16 bacterial genera co-occurred with tet W gene. Co-occurrence patterns were revealed distinct community interactions between aerobic/anoxic/aerobic and oxidation ditch systems. The redundancy analysis model plot of the bacterial community composition clearly demonstrated that the sludge samples were significant differences among those from the different geographical areas,and the shifts in bacterial community composition were correlated with ARGs. Together,these findings from the present study will highlight the potential risks of ARGs and bacterial populations carrying these ARGs, and enable the development of suitable technique to control the dissemination of ARGs from WWTPs into aquatic environments.

关键词： Antibiotic resistance genes Activate sludge Bacterial community Network analysis Mobile genetic elements

Ferric ion-ascorbic acid complex catalyzed calcium peroxide for organic wastewater treatment:Optimized by response surface method

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Chinese Chemical Letters 2021年第11期32卷 3387-3392页

作者： Deling Yuan Chen Zhang Shoufeng Tang Zetao Wang Qina Sun Xiaoyu Zhang Tifeng Jiao Qingrui Zhang Hebei key laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse Hebei Key Laboratory of Applied ChemistrySchool of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China State key laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Hydrogen peroxide(H_(2)O_(2))disproportionation,iron precipitation,and narrow pH range are the drawbacks of traditional Fenton *** surmount these barriers,we proposed a ferric ion(Fe^(3+))-ascorbic acid(AA)complex catalyzed calcium peroxide(CaO_(2))Fenton-like system to remove organic dyes in *** collaborative Fe^(3+)/AA/CaO_(2)system presented an obvious improvement in the methyl orange(MO)decolorization,and also effectively eliminated other *** surface method was employed to optimize the running parameters for this coupling *** the optimized arguments(2.76 mmol/L Fe^(3+),0.68 mmol/L AA,and 4 mmol/L CaO_(2)),the MO removal achieved 98.90%after 15 min at pH 6.50,which was close to the computed outcome of 99.30%.Furthermore,this Fenton-like system could perform well in a wide range of pH(3-11),and enhance the H_(2)O_(2)decomposition and Fe ions *** scavenger experiment result indicated that hydroxyl radical,superoxide anion free radical,and singlet oxygen were acted on the dye ***,electron spin resonance analysis corroborated that the existences of these active species in the Fe^(3+)/AA/CaO_(2)*** study could advance the development of Fenton-like technique in organic effluent disposal.

关键词： Ferric ion Ascorbic acid Calcium peroxide Response surface method Dye removal

From ultra-low friction to superlubricity state of black phosphorus:Enabled by the critical oxidation and load

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Friction 2023年第10期11卷 1829-1844页

作者： Qiang LI Fenghua SU Yanjun CHEN Jianfang SUN School of Mechanical&Automotive Engineering South China University of TechnologyGuangzhou 510641China Guangdong Provincial key laboratory of technique and Equipment for Macromolecular Advanced Manufacturing South China University of TechnologyGuangzhou 510640China

Based on the density functional theory(DFT),we investigate the friction properties of inevitable oxidized black phosphorus(o-BP).o-BP with the weaker interlayer adhesion exhibits their great potential as a solid *** the zero load,the friction property of o-BP is adjusted by its oxidation ***,ultra-low friction of P4O2(50%oxidation,O:P=2:4=50%)is obtained,which is attributed to the upper O atoms with lower sliding resistance in the O channel formed by lower layer O *** attractive,we observe superlubricity behavior of o-BP at the critical load/distance due to the flattening potential energy surface(PES).The flattening PES is controlled by the electrostatic role for the high-load(P4O3,O:P=3:4=75%),and by the electrostatic and dispersion roles for the low-load(P4O2).Distinctly,the transform from ultra-low friction to superlubricity state of black phosphorus(BP)can be achieved by critical oxidation and load,which shows an important significance in engineering *** addition,negative friction behavior of o-BP is a general phenomenon(Z>Z_(min),Z_(min)is the interlayer distances between the outermost P atoms of minimum load.),while its surface-surface model is different from the fold mechanism of the tip-surface model(Z_(0)Z_(min)).In summary,o-BP improves the friction performance and reduces the application limitation,comparing to graphene(Gr),MoS2,and their oxides.

关键词： oxidized black phosphorus(o-BP) ultra-low friction superlubricity critical load/distance first-principles

Fluorescence characterization of the thermal stability of collagen mimic peptides

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Chinese Chemical Letters 2017年第5期28卷 963-967页

作者： Xiu-Xia Sun Jun Fan Yan-Nan Hou Shuo Liang Yu-Ping Zhang Jian-Xi Xiao State key laboratory of applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou University key laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsWuhan Institute of Physics and MathematicsChinese Academy of Sciences

The thermal stability of triple helical structure plays a critical role in collagen biosynthesis,function and *** technique was utilized to characterize the thermal stability of synthetic collagen mimic *** spectroscopy is widely used with easy access all around the world because of its inexpensive instrumentation,low operation cost,easy operation,and high *** we have developed an alternative fluorescence method to detect the thermal stability of collagen mimic *** have demonstrated that fluorescence spectroscopy could measure the thermal stability of collagen mimic peptides with low concentrations under different *** highly sensitive fluorescence self-quenching assay will greatly expedite the studies of sequence-dependent properties of collagen mimic peptides,and it has great potential in the application of determining the thermal stability of triple helix systems such as collagens,collectins,adiponectin,macrophage scavenger and C1q.

关键词： Collagen Peptides Thermal stability Fluorescence Triple helix

Nanostructured perovskite oxides as promising substitutes of noble metals catalysts for catalytic combustion of methane

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Chinese Chemical Letters 2018年第2期29卷 252-260页

作者： Ji Yang Yanbing Guo key laboratory of Pesticide & Chemical Biology of Ministry of Education Institute of Environmental and Applied ChemistryCollege of Chemistry Central China Normal University

Heterogeneous catalytic combustion provides a feasible technique for high efficient methane *** ABO_3-type materials have received renewed attention as a potential alternative for noble metals supported catalysts in catalytic methane combustion due to excellent hydrothermal stability and sulfur resistance. Recently, the emergence of nanostructured perovskite oxides（such as threedimensional ordered nanostructure, nano-array structure） with outstanding catalytic activity has further driven methane catalytic combustion research into spotlight. In this review, we summarize the recent development of nanostructured perovskite oxide catalysts for methane combustion, and shed some light on the rational design of high efficient nanostructured perovskite catalysts via lattice oxygen activation,lattice oxygen mobility and materials morphology engineering. The emergent issues needed to be addressed on perovskite catalysts were also proposed.

关键词： Nanostructured perovskites Mesoporous and macroporous Nano-array catalysts Methane oxidation Catalytic combustion

Different non-radical oxidation processes of persulfate and peroxymonosulfate activation by nitrogen-doped mesoporous carbon

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Chinese Chemical Letters 2020年第10期31卷 2614-2618页

作者： Hai-Bin Qiu Pu-Can Guo Li Yuan Guo-Ping Sheng CAS key laboratory of Urban Pollutant Conversion Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Activated persulfate oxidation is an emerging advanced oxidation process for organic pollutant *** to different molecular structures and oxidation potentials,persulfate(PDS)and peroxymonosulfate(PMS)may show different degradation performances due to various catalytic mechanisms even by the same *** this study,the nitrogen-doped mesoporous carbon(N-OMC)was applied to activate PDS and PMS for degrading a model organic pollutant phenol to reveal their activation *** sults show that both PDS and PMS could be efficiently activated by *** degradation of phenol fitted well with pseudo-first-order kinetics,whose kinetic constants increased with the increase of pH,PDS/PMS dosage,and N-OMC *** on quenching experiments and electron spin resonance spin-trapping technique,the N-OMC was found to activate PDS and PMS via nonradical process of electron transfer and singlet oxygen formation,respectively,instead of the commonly observed radical *** wo rk will be useful to understand the activation processes of PDS and PMS,and benefit for the development of catalysts for pollutant degradation.

关键词： Nitrogen-doped mesoporous carbon Persulfate Peroxymonosulfate Non-radical process Electron transfer Singlet oxygen formation

Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields

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Chinese Journal of Polymer Science 2024年第7期42卷 958-967,I0008页

作者： Yun-Zhi Huang Xiao-Xiao Liu Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu National Engineering Research Center of Novel Equipment for Polymer Processing Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced ManufacturingSchool of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou 510641China School of Advanced Manufacturing Technology Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China

Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM ***,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors *** structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene ***,the result showed that CPP-SS can significantly improve theσof ***,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be *** work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields.

关键词： Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene Graphene Electromagnetic interface