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Carbon nanotubes as outstanding targets for laser-driven particle acceleration

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Nano Research 2023年第11期16卷 12572-12578页

作者： wenjun Ma State Key Laboratory of Nuclear Physics and Technology and Key Laboratory of HEDP of the Ministry of EducationCAPTPeking UniversityBeijing 100871China Beijing Laser Acceleration Innovation Center Beijing 101400China Institute of Guangdong Laser Plasma Technology Guangzhou 510540China

Under the irradiation of ultraintense laser pulses,targets made of gas,solid,or artificial materials can generate high-energy electrons,ions,and X-rays comparable to conventional accelerators or national light source *** and creating high-performance targets are the core problems for laser *** and nanomaterials can help to build ideal targets that do not exist in *** paper reviews the advances in exploiting carbon nanotubes as outstanding targets for laser-driven particle acceleration in memory of *** Xie,the inventor of the fabrication *** hope that the successful implementation of such targets in enhanced ion acceleration,high-efficiency electron acceleration,and brilliant X-ray generation could attract more interdiscipline interests and promote the development of this field.

关键词： laser acceleration laser-driven ion acceleration X-ray sources carbon nanotubes

Exponential and polynomial decay for a laminated beam with Fourier's law of heat conduction and possible absence of structural damping

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Frontiers of Mathematics in China 2021年第4期16卷 997-1021页

作者： wenjun LIU Weifan zHAO School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

We study the well-posedness and decay properties of a one-dimensional thermoelastic laminated beam system either with or without structural damping,of which the heat conduction is given by Fourier's law effective in the rotation angle *** show that the system is well-posed by using the Lumer-Philips theorem,and prove that the system is exponentially stable if and only if the wave speeds are equal,by using the perturbed energy method and Gearhart-Herbst-Prüss-Huang ***-more,we show that the system with structural damping is polynomially stable provided that the wave speeds are not equal,by using the second-order energy *** the speeds are not equal,whether the system without structural damping may has polynomial stability is left as an open problem.

关键词： Laminated beam Fourier’s law exponential stability lack of exponential stability polynomial stability

Pacific-Indian interocean circulation of the Antarctic Intermediate Water around South Australia

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Acta Oceanologica Sinica 2017年第7期36卷 4-14页

作者： YAO wenjun SHI Jiuxin Key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100China

On the basis of the salinity distribution of isopycnal（σ_0=27.2 kg/m^3） surface and in salinity minimum, the Antarctic Intermediate Water（AAIW） around South Australia can be classified into five types corresponding to five regions by using in situ CTD observations. Type 1 is the Tasman AAIW, which has consistent hydrographic properties in the South Coral Sea and the North Tasman Sea. Type 2 is the Southern Ocean（SO） AAIW, parallel to and extending from the Subantarctic Front with the freshest and coldest AAIW in the study area. Type 3 is a transition between Type 1 and Type 2. The AAIW transforms from fresh to saline with the latitude declining（equatorward）. Type 4, the South Australia AAIW, has relatively uniform AAIW properties due to the semienclosed South Australia Basin. Type 5, the Southeast Indian AAIW, progressively becomes more saline through mixing with the subtropical Indian intermediate water from south to north. In addition to the above hydrographic analysis of AAIW, the newest trajectories of Argo（Array for real-time Geostrophic Oceanography） floats were used to constructed the intermediate（1 000 m water depth） current field, which show the major interocean circulation of AAIW in the study area. Finally, a refined schematic of intermediate circulation shows that several currents get together to complete the connection between the Pacific Ocean and the Indian Ocean. They include the South Equatorial Current and the East Australia Current in the Southwest Pacific Ocean, the Tasman Leakage and the Flinders Current in the South Australia Basin, and the extension of Flinders Current in the southeast Indian Ocean.

关键词： Antarctic Intermediate Water Pacific-Indian interocean circulation South Australia World Ocean Circulation Experiment Argo

Utilizing surfactants to control the sorption,desorption, and biodegradation of phenanthrene in soil-water system

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Journal of Environmental Sciences 2013年第7期25卷 1355-1361页

作者： Haiwei Jin wenjun zhou Lizhong zhu Department of Environmental Science Zhejiang University zhejiang Provincial Key Laboratory of0rganic Pollution Process and Control

An integrative technology including the surfactant enhanced sorption and subsequentdesorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultural soils, cationic-nonionic mixed surfactant- enhanced sorption of organic contaminants onto soils could reduce their transfer to plants, therefore safe-guarding agricultural production. After planting, residual surfactants combined with added nonionic surfactant could also promote thedesorption and biodegradation of residual phenanthrene, thus providing a cost-effective pollution remediation technology.0ur results showed that the cationic-nonionic mixed surfactantsdodecylpyridinium bromide （DDPB） and Triton X-100 （TX100） significantly enhanced soil retention of phenanthrene. The maximum sorption coefficient Kd＊ of phenanthrene for contaminated soils treated by mixed surfactants was about24.5 times that of soils without surfactant （Kd ） and higher than the combined effects of DDPB and TX100 individually, which was about 16.7 and 1.5 times Kd , respectively.0n the other hand, TX100 could effectively remove phenanthrene from contaminated soils treated by mixed surfactants, improving the bioavailability of organic pollutants. Thedesorption rates of phenanthrene from these treated soils were greater than 85% with TX100 concentration above2000 mg/L and approached 100% with increasing TX100 concentration. The biodegradation rates of phenanthrene in the presence of surfactants reached over 95% in30days. The mixed surfactants promoted the biodegradation of phenanthrene to some extent in 10-22days, and had no obvious impact on phenanthrene biodegradation at the end of the experiment. Results obtained from this study provide some insight for the production of safe agricultural products and a remediation scheme for soils slightly contaminated with organic pollutants.

关键词： surfactant phenanthrene sorption desorption degradation soil-water system

The Stability of Imitation Dynamics with Continuously Distributed Delays

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Journal of Systems Science & Complexity 2023年第5期36卷 2067-2081页

作者： FANG Caiya YANG Hui PI Jinxiu WU wenjun School of Mathematics and Statistics Guizhou UniversityGuizhou 550025China Guizhou Provincial Key Laboratory for Games Decision Making and Control SystemsGuiyang 550025China

This paper investigates imitation dynamics with continuously distributed *** realistic technological,economic,and social environments,individuals are involved in strategic interactions simultaneously while the influences of their decision-making may not be observable *** shows that there exists a time delay *** distributions of delay are further considered to efficiently lucubrate the stability of interior equilibrium in the imitation dynamics with continuous distributions of delay in the two-strategy game ***,when the delay follows the uniform distributions and Gamma distributions,the authors present that interior equilibrium can be asymptotically ***,when the probability density of the delay is general density,the authors also determine a sufficient condition for stability derived from the expected *** but not least,the interested but uncomplicated Snowdrift game is utilized to demonstrate our theoretical results.

关键词： Continuous distributed delay evolutionary games imitation dynamics stability

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Validation and application of soil moisture active passive sea surface salinity observation over the Changjiang River Estuary

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Acta Oceanologica Sinica 2020年第4期39卷 1-8页

作者： Qiong Wu Xiaochun Wang Wenhao Liang wenjun zhang School of Atmospheric Science Nanjing University of Information Science and TechnologyNanjing 210044China School of Marine Science Nanjing University of Information Science and TechnologyNanjing 210044China Joint Institute for Regional Earth System Science and Engineering University of California at Los AngelesLos Angeles 90095USA

Using sea surface salinity(SSS)observation from the soil moisture active passive(SMAP)mission,we analyzed the spatial distribution and seasonal variation of SSS around Changjiang River(Yangtze River)Estuary for the period of September 2015 to August ***,we found that the SSS from SMAP is more accurate than soil moisture and ocean salinity(SMOS)mission observation when comparing with the in situ ***,the SSS signature of the Changjiang River freshwater was analyzed using SMAP data and the river discharge data from the Datong hydrological *** results show that the SSS around the Changjiang River Estuary is significantly lower than that of the open ocean,and shows significant seasonal *** minimum value of SSS appears in July and maximum SSS in *** root mean square difference of daily SSS between SMAP observation and in situ observation is around 3 in both summer and winter,which is much lower than the annual range of SSS *** summer,the diffusion direction of the Changjiang River freshwater depicted by SSS from SMAP is consistent with the path of freshwater from in situ observation,suggesting that SMAP observation may be used in coastal seas in monitoring the diffusion and advection of freshwater discharge.

关键词： soil moisture active passive mission in situ observation soil moisture and ocean salinity mission sea surface salinity Changjiang River(Yangtze River)Estuary freshwater plume

Arsenic(V)removal from groundwater by GE-HL nanofiltration membrane:effects of arsenic concentration,pH,and co-existing ions

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Frontiers of Environmental Science & Engineering 2009年第4期3卷 428-433页

作者： Xiaowei WANG wenjun LIU Desheng LI Weifang MA School of Environmental and Municipal Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China School of Civil Engineering and Architecture Beijing Jiaotong UniversityBeijing 100044China

A laboratory-scale investigation was performed to study arsenic(As(V))removal by negatively charged GE-HL nanofiltration(NF)membrane in simulated drinking *** of As(V)concentration(0–200μg·L–1),pH,and co-ions and counter-ions were *** NF membrane presented good stability,and the rejection rates exceeded 90%.The rejection rates of As(V)decreased with the increase of As(V)concentration,while it increased with the increase of pH(reached 96%at pH 6.75).Moreover,a negative relationship was observed between the co-existing ions of Cl^(–),Na^(+),SO_(4)^(2–),and Ca^(2+)and the removal of As(V),in which bivalent ions presented more significant effects than monovalent ions.

关键词： nanofiltration(NF) rejection rate co-existing ion co-ion counter-ion

Spatiotemporal variations of benthic macrofaunal community in the Xiamen Amphioxus Nature Reserve, eastern South China Sea

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Acta Oceanologica Sinica 2020年第6期39卷 10-18页

作者： Yiyong Rao Lizhe Cai wenjun Li Xinwei Chen Deyuan Yang College of the Environment and Ecology Xiamen UniversityXiamen 361102China Key Laboratory of the Coastal and Wetland Ecosystems(Xiamen University) Ministry of EducationXiamen 361102China

In order to realize the spatiotemporal variations of benthic macrofaunal communities at the"Amphioxus Sand"habitat,six surveys including four seasons and three consecutive summers(i.e.,2014,2015 and 2016)were conducted in two core sites,i.e.,Huangcuo(HC)and Nanxian-Shibaxian(NX),in the Xiamen Amphioxus Nature Reserve in China.A total of 155 species of macrofauna were recorded,therein,polychaetes were dominant in terms of species number and *** spatiotemporal variations of macrofaunal communities were *** density of polychaetes and the biomass of molluscs in the HC site were higher than those in the NX *** were more diverse and abundant in the cold seasons(winter and spring)than that in the warm seasons(summer and autumn).The annual variations of macrofaunal communities may be attributed to the changes in sediment texture among the three years of the *** variations in macrofaunal communities were mainly related to the proportion of polychaetes within the *** addition,the density of amphioxus(include Branchiostoma japonicum and ***)was negatively correlated to that of polychaetes,bivalves,and *** was less likely to be found in the sediments with higher silt and clay *** biotic indices including Margaref’s richness index(d),Peilou’s evenness index(J′),Shannon-Wiener diversity index(H′),AMBI and M-AMBI were calculated in the present *** seems suitable in assessing benthic health at the"Amphioxus Sand"habitat,and a potential risk of ecological health in Xiamen Amphioxus Nature Reserve should be aware.

关键词： spatiotemporal variation Amphioxus Sand benthic macrofaunal community Branchiostoma biotic index

Status of hyperhomocysteinemia in China: results from the China Stroke High-risk Population Screening Program, 2018

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Frontiers of Medicine 2021年第6期15卷 903-912页

作者： wenjun Tu Feng Yan Baohua Chao Xunming Ji Longde Wang Institute of Radiation Medicine Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin300192China The General Office of Stroke Prevention Project Committee National Health Commission of the People’s Republic of ChinaBeijing100053China Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing100070China Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijing100053China

A nationwide survey was conducted from October 2018 to September 2019 to assess the prevalence of hyperhomocysteinemia(Hhcy)and its influencing factors in China.A standardized questionnaire was used to collect *** was defined as the level of serum homocysteine(HCY)≥15.0µmol/*** H-type hypertension(HHYP)was defined as hypertension with an elevated serum HCY(≥15.0µmol/L).Finally,110551 residents≥40 years of age from 31 provinces in the mainland of China were ***,the median serum HCY level was 10.9µmol/L(interquartile range 7.9–15.1).A total of 28633 participants(25.9%)were defined as *** Hhcy prevalence ranged from 7.9%in Shanghai to 56.8%in *** data showed that serum HCY levels were associated with age,male gender,cigarette smoking,hypertension,diabetes,ethnicity,endurance in exercise(inverse),and fruit and vegetable intake(inverse).In addition,15486 participants were defined as HHYP,and the rate was 14.0%.HHYP was an independent predictor of stroke with an adjusted odds ratio of 1.752(95%CI 1.338–2.105).The geographical distribution pattern of the Hhcy epidemic reflects dynamic differences,and national strategies should be carried out to further improve the care of patients with Hhcy across China.

关键词： homocysteine hyperhomocysteinemia H-type hypertension Chinese