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Applied Geophysics 2022年第3期19卷 447-457,472页

作者： Jiang Fu-Yu qiao pei-xuan Gao Li-Kun Chen Hai-Jun School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China The First Geological Brigade of Jiangsu Bureau of Geology and Mineral Exploration Nanjing 210041China Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing 210029China

High-density polyethylene(HDPE)film leakage location detection is frequently accomplished using the double-electrode *** electric potential and potential difference are the main physical parameters in the double-electrode *** to the impact of the complex geoelectric environment,the electric potential and the electric potential difference are not sensitive enough to respond to minimal *** tiny leaking area cannot be precisely located using the electric potential and electric potential *** the COMSOL Multiphysics software,this study created a standard geoelectric model of the double-electrode *** calculated a new parameter—the G parameter through secondary electric potential difference—based on the response characteristics of the electric potential and the electric potential difference while the HDPEﬁlm is *** experiment demonstrates that the G parameter is more sensitive than the electric potential and electric potential difference for detecting the leaking area of HDPE *** G parameter is more effective at detecting leakage than the electric potential and electric potential *** results of this study can be used to locate HDPEﬁlm leakage areas in a landﬁll.

关键词： landfill environmental geophysics high-density polyethylene film pollution prevention

Distributed sampling measurement method of network traffic in high-speed IPv6 networks

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Journal of Systems Engineering and Electronics 2007年第4期18卷 835-840页

作者： Pan qiao pei Changxing State Key Lab. of Integrated Services Networks Xidian Univ. Xi'an 710071 P. R. China

With the advent of large-scale and high-speed IPv6 network technology, an effective multi-point traffic sampling is becoming a necessity. A distributed multi-point traffic sampling method that provides an accurate and efficient solution to measure IPv6 traffic is proposed. The proposed method is to sample IPv6 traffic based on the analysis of bit randomness of each byte in the packet header. It offers a way to consistently select the same subset of packets at each measurement point, which satisfies the requirement of the distributed multi-point measurement. Finally, using real IPv6 traffic traces, the conclusion that the sampled traffic data have a good uniformity that satisfies the requirement of sampling randomness and can correctly reflect the packet size distribution of full packet trace is proved.

关键词： network measurement traffic sampling IPv6 distributed measurement Shannon entropy

First principles study of Fenton reaction catalyzed by FeOCl:reaction mechanism and location of active site

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Rare Metals 2019年第8期38卷 783-792页

作者： xuan-xuan Ji Hai-Feng Wang pei-Jun Hu Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis and Centre for Computational Chemistry School of Chemical and Molecular Engineering East China University of Science and Technology Shanghai 200237 China School of Chemistry and Chemical Engineering The Queen’s University of Belfast Belfast BT9 5AZ UK

Fe-based solid catalysts in promoting Fenton reaction to generate ·OH radical has drawn much attention,and interestingly,FeOCl was reported to have superior activity compared with the traditional Fe2 O3 ***,the mechanism of Fenton reaction on FeOCl and the origin of high activity remain ***,by virtue of DFT+ U calculations,the H2 O2 decomposition and conversion mechanism on FeOCl(100)surface were systematically *** is found that on clean FeOCl(100)surface,the exposed[Fe^3+-Fe^3+]sites can hardly break O-O bond of H2 O2 into OH groups,but instead H2 O2 tends to dehydrogenate by the surface lattice O,resulting in a series of side reactions and final conversion into O2,while the left H atoms gradually saturate the surface lattice O and reduce Fe^3+ into Fe^2+.On fully H-covered FeOCl(100),H2O2 can efficiently dissociate at[Fe^2+-Fe^2+]sites into two OH,but OH binds with Fe^2+ so strongly that it cannot desorb as OH radical as easily as that on Fe^3+.Interestingly,FeOCl(100)tends to be partially protonated in the real acid solution,which,along with H2 O2 dehydrogenation,results in the formation of active unit [Fe^2+-Fe^3+].On[Fe^2+-Fe^3+]unit,H2 O2 can easily break its O-O bond and OH at Fe3+ can desorb as OH radical,while the other OH at Fe^2+ couples with the surface H into H2O and finish the catalytic *** comparison,Fe2 O3(012)cannot provide enough [Fe^2+-Fe^3+] active units due to the relative difficulty in H2 O2 dehydrogenation,which accounts for its inferior catalytic efficiency for Fenton reaction.

关键词： Fenton reaction FeOCl Density functional theory H2O2 Active site

Positive Periodic Solution of a Discrete Predator-prey Patch-system

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 627-642页

作者： Shu-yuan Shen pei-xuan Weng School of Mathematics South China Normal University Guangzhou 510631 China Nanhai College South China Normal University Foshan Cuangdong 528225 China

A periodic difference predator-prey model with Holling-（m ＋ 1）（m 〉 2） type functional response and impulses is established. Sufficient conditions are derived for the existence of periodic solutions by using a co... 详细信息

关键词： Continuation theorem impulse Holling-(m +1) (m 〉 2) type functional response discretepredator-prey patch-system periodic solution

Traveling waves in nonlocal diffusion systems with delays and partial quasi-monotonicity

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Applied Mathematics(A Journal of Chinese Universities) 2011年第4期26卷 464-482页

作者： XU Zhao-quan WENG pei-xuan Department of Mathematics South China Normal University Gungzhou 510631 China.

This paper is devoted to the study of a three-dimensional delayed system with nonlocal diffusion and partial quasi-monotonicity. By developing a new definition of upper-lower solutions and a new cross iteration scheme, we establish some existence results of traveling wave solutions. The results are applied to a nonlocal diffusion model which takes the three-species Lotka-Volterra model as its special case.

关键词： Traveling wave nonlocal diffusion partial quasi-monotonicity upper and lower solution cross iteration scheme.

Traveling Waves for Nonlocal and Non-monotone Delayed Reaction-difusion Equations

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Acta Mathematica Sinica,English Series 2013年第11期29卷 2159-2180页

作者： Zhi Ting XU pei xuan WENG School of Mathematical Sciences South China Normal University

We study the existence of traveling wave solutions for a nonlocal and non-monotone delayed reaction-diffusion equation. Based on the construction of two associated auxiliary reaction diffusion equations with monotonicity and by using the traveling wavefronts of the auxiliary equations, the existence of the positive traveling wave solutions for c 〉 c. is obtained. Also, the exponential asymptotic behavior in the negative infinity was established. Moreover, we apply our results to some reactiondiffusion equations with spatio-temporal delay to obtain the existence of traveling waves. These results cover, complement and/or improve some existing ones in the literature.

关键词： Nonlocal non-monotone delayed reaction-diffusion equation traveling wave solutions auxiliary equation

Recent advances of morphology adaptive nanomaterials for anti-cancer drug delivery

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Progress in Natural Science:Materials International 2020年第5期30卷 555-566页

作者： Dongbing Cheng Zengying qiao Lixue xuan Hao Wang School of Chemistry Chemical Engineering & Life Science Wuhan University of Technology CAS Center for Excellence in Nanoscience Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Technology (NCNST) Department of Breast Surgery Nation Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Henan Institute of Advanced Technology Zhengzhou University

The morphology of nanomaterials combines the characteristics of their size, shape and spatial structure. Owing to the improved spatiotemporal control of the nanocarriers for anti-cancer drug delivery, the morphology adaptive nanomaterials have received tremendous attention in the field of nanomedicine, while they are able to respond through chemical or physical change. In this review, we summarize the recent advancements of morphology adaptive nanomaterials and their application in anti-cancer drug delivery system, wherein the size, shape and spatial structure of nanocarriers can be changed to adapt the complex living system, thus overcoming the pathological barriers in drug delivery. The overview of the recent examples shows that each step of delivery process can be improved by the morphology adaption, which represents the great potential for clinic translation of morphology adaptive nanomaterials.

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Effects of Protein on the Detection of Chlorobenzenes in Fish and Their Elimination by Modified QuEChERS Method

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Chemical Research in Chinese Universities 2013年第6期29卷 1063-1067页

作者： DENG qiao-qiao LI Gui-zhi LIU pei-pei ZHANG Xing-mei LIU Yong-ming College of Chemistry and Chemical Engineering Yantai University Yantai 264005 P.R.China

Molecular fluorescence spectrometry, resonance Rayleigh scattering and gas chromatography-mass spectroscopy（GC-MS） were used to study the effect of pure fish serum albumin（FSA） as the model protein on the extraction of three chlorobenzenes（CBs： 1,3-DCB, 1,2-DCB and 1,2,4-TCB; DCB=dichlorobenzene; TCB=trichlorobenzene） in fish samples. The results show that there was a strong binding effect between CB and FSA. In an aqueous solution of 90%（volume fraction） acetone, a slow but full protein denaturation might take place, which would cause the unfolding of protein and the releasing of CBs. Based on these results, a QuEChERS（quick, easy, cheap, effective, rugged and safe） method was modified by replacing the traditional acetonitrile with acetone aqueous solution in the present work. This modified QuEChERS method was applied in the determination of CBs in fish samples. The spiked recoveries and the limits of detection were 80.4%--118.3% and 2.4--7.3 ng/g, respectively. This paper proposes a new strategy by slowing down the protein denaturation and releasing bound organic compounds to enhance the extraction efficiency of CBs in fish samples.

关键词： Chlorobenzene Modified QuEChERS(quick,easy,cheap,effective,rugged and safe) method Gas chromatography-mass spectroscopy Fluorescence spectrometry Resonance Rayleigh scattering

Miocene paleoenvironmental evolution based on benthic foraminiferal assemblages in the Lufeng Sag, northern South China Sea

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Acta Oceanologica Sinica 2019年第3期38卷 124-137页

作者： Liyuan Xue xuan Ding Renjie pei Xiaoqiao Wan School of Ocean Sciences China University of Geosciences School of Earth Sciences and Resources China University of Geosciences

The Miocene epoch marks the most crucial period during the Cenozoic cooling trend, characterized by the Middle Miocene Climatic Optimum(MMCO) and a series of short–lived cooling events(Miocene isotope events).To understand the paleoenvironmental evolution along the shallow water shelf in the South China Sea during the Miocene, the benthic foraminiferal assemblage and total organic carbon content(TOC) were analyzed at Hole LF14 located in the Lufeng Sag, northern South China Sea. Three benthic foraminiferal assemblages(e.g., the Uvigerina spp. assemblage, the Cibicides spp. assemblage, and the Cibicidoides spp. assemblage), corresponding to different watermass conditions, were recognized based on Q–mode factor analysis. Early studies suggested that Hole LF14 was deposited under semienclosed bay, middle to outer shelf or even upper bathyal environment during ～18.7–4.53 Ma. The dominant Uvigerina spp. assemblage was characterized by low diversity and shallow infaunal to infaunal species, indicating a warm, low–oxygenation and eutrophic conditions since the Early Miocene to MMCO(～18.7–14.24 Ma). An abrupt sea level drop and significant faunal changes were recorded during 14.24–13.41 Ma, suggesting development of the East Antarctic Ice Sheets, which resulted in a drop of sea level and change in benthic foraminiferal assemblages along the shallow water shelf. Beyond the Uvigerina ***, the Cibicides spp. assemblage became important during the middle–late Middle Miocene(14.24–11.54 Ma). This assemblage was dominated by epifaunal species with relative high diversity, suggesting high–energy, high–oxygenation and oligotrophic conditions with episodic supply of organic food. The dominant Cibicidoides spp. assemblage with high diversity, indicates a mesotrophic conditions with relative high–oxygen content during the Late Miocene to Pliocene(11.54–4.53 Ma). The appearance and continuous occurrence of Ammonia spp. and Pseudorotalia spp. since 10.02 Ma, may reflect the i

关键词： South China Sea Lufeng Sag Miocene benthic foraminiferal assemblage total organic carbon shelf paleoenvironment

Two Different Burster Spatial Distributions of Gamma-Ray Bursts?

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Chinese Physics Letters 1996年第12期13卷 957-960页

作者： CHE Hai-hong LI Ti-pei YANG Yu-xuan Shannxi Astronomical Observatory Chinese Academy of SciencesLintong 710600 Cosmic Ray and High Energy Astrophysics Laboratory Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100039 Department of Astronomy Beijing Normal UniversityBeijing 100875

By using the first,second and third electronic burst and transcient source experiment catalogs,a joint analysis of spatial and temporal distributions and hardness ratios of gamma-ray bursts is *** point features at C_(max)/C_(min) ~6 are *** probably indicates the existence of two components of burster population which have distinct spatial distributions.

关键词： trans Turning Spatial