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DYNAMICS ON A HOLLING II PREDATOR-PREY MODEL WITH STATE-DEPENDENT IMPULSIVE CONTROL

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International Journal of Biomathematics 2012年第3期5卷 93-110页

作者： bing liu YE TIAN BAOLIN KANG Department of Mathematics Anshan Normal University Anshan 114007 Liaoning P. R. China Department of Mathematics Liaoning Normal University Dalian 116029 Liaoning P. R. China Department of Applied Mathematics Dalian University of TechnologyDalian 116024 Liaoning P. R. China

to biological and chemical control strategy for pest control, a Holling II func- tional response predator-prey system concerning state-dependent impulsive control is investigated. We define the successor functions of semi-continuous dynamic system and give an existence theorem of order 1 periodic solution of such a system. By means of sequence convergence rules and quMitative analysis, we successfully get the conditions of existence and attractiveness of order 1 periodic solution. Our results show that our method used in this paper is more efficient and easier than the existing methods to prove the existence and attractiveness of order 1 periodic solution.

关键词： Holling II predator-prey system order 1 periodic solution successor function state-dependent impulsive control.

Response of groundwater to the process of reservoirs group regulation and storage in Manas River Basin in Xinjiang

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International Journal of Agricultural and Biological Engineering 2020年第1期13卷 224-233页

作者： bing liu Guang Yang Xinlin He College of Water Conservancy and Construction Engineering Shihezi UniversityShihezi 823003China Key Laboratory of Modern Water Saving Irrigation.of Xinjiang production and Construction Corps Shihezi UniversityShihezi 823003China Department of Geological Sciences Center for Water ResearchUniversity of Texas at San AntonioTX 78249United States

Reservoir regulation and storage is the main approach to alleviate the water pressure caused by the uneven spatial and temporal distribution of surface water resources in arid areas of northwest *** the regulation and storage of the reservoir affect the conditions of recharge and discharge of groundwater,the process of regional surface-groundwater transformation tends to be *** Manas River basin that lies on the northern slope of Tianshan Mountain in Northwest China was taken in this study as a case.A numerical model of groundwater in basin plain area was established,and the influence of reservoir regulation on groundwater level was *** results showed that the total recharge of groundwater in the study area was 75.539 million m3,the total discharge of groundwater was 82.66 million m3,and the groundwater in the study area was in a negative equilibrium state,with a difference of-69.27 million *** water balance method was used to verify the *** total recharge of groundwater was 74.34 million m3,the total discharge of groundwater was 80.726 million m3,and the calculation result of the numerical simulation of the supplementary displacement was 63.82 million m3,basically consistent with the calculation result of the water balance *** reservoir storage method has obvious changes to the groundwater level around the *** simulation results of groundwater numerical model showed that when the reservoir was in normal operation,the leakage of the reservoir was 27.35 million m3;when the reservoir was operated at low water level,the leakage of the reservoir was the smallest,13.47 million *** reservoir has the largest amount of leakage of 41.85 million m3 when operated at water storage *** the reservoir was operated at the lowest water level,the groundwater level around the reservoir was declining compare to the normal operating water *** maximum drop of the groundwater observation well was 2.1 m,and the maxi

关键词： Manas River Basin water balance numerical simulation reservoir regulating groundwater

Kinetic Model of Hydrogenation for Removal of Trace Olefins from Alkylation Mixture Formed during Linear Alkylbenzene Synthesis

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China Petroleum Processing & Petrochemical Technology 2019年第1期21卷 46-54页

作者： Ren Jie liu bing Shen Lian College of Chemical Engineering Zhejiang University of Technology

Through the hydrogenation experiments for removal of olefin impurities in effluent mixture obtained from alkylation reactor for linear alkylbenzene synthesis, the reaction kinetics was studied. The experimental results showed that the catalytic activity of Pd/Al2 O3 among four kinds of catalysts was the highest, and the olefin conversion reached 100%when the reaction temperature was higher than 140 ℃. The kinetic model was established through parameters *** experimental validation of the kinetic model showed that the kinetic model had higher simulation accuracy. The results of prediction by the kinetic model indicated that with the intensification of reaction conditions, the olefin conversion would increase and the bromine index of the linear alkyl benzene would decrease. Under the conditions covering a WHSV of 2.0 h^(-1),a temperature of 90 ℃, and a hydrogen partial pressure of 1.5 MPa, the olefin conversion was 99.67%, and the bromine index of the linear alkyl benzene could be reduced to less than 20.00 mgBr/(100 g).

关键词： hydrogenation reaction kinetics linear alkylbenzene removal of olefin impurity bromine index

Novel method to determine effective length of quantum confinement using fractional-dimension space approach

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Frontiers of physics 2015年第4期10卷 97-102页

作者： Hua Li bing-Can liu bing-Xin Shi Si-Yu Dong Qiang Tian Department of Physics Beijing Normal University Beijing 100875 China Department of Fundamental Courses Academy of Arraored Forces Engineering Beijing 100072 China

The binding energy and effective mass of a polaron confined in a GaAs film deposited on an AlGal-xAs substrate are investigated, for different film thickness values and aluminum concentra- tions and within the framework of the fractional-dimensional space approach. Using this scheme, we propose a new method to define the effective length of the quantum confinement. The limita- tions of the definition of the original effective well width are discussed, and the binding energy and effective mass of a polaron confined in a GaAs film are obtained. The fl-actional-dimensional theo- retical results are shown to be in good agreement with previous, more detailed calculations based on second-order perturbation theory.

关键词： fractional-dimensional approach effective length of quantum confinement polaron effect GaAs film

Orthogonal Alignment InAs Islands Formation on GaAs Tensile Strained Layer Grown on (001) InP Substrate by Low Pressure Metal-Organic Chemical Vapor Deposition

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Chinese Physics Letters 1998年第11期15卷 843-845页

作者： GAO Chun-xiao WANG Ben-zhong liu bing-bing liu Shi-yong ZOU Guang-tian State Key Laboratory for Superhard Materials Jilin UniversityChangchun 130023 State Key Laboratory on Integrated Optoelectronics Jilin University RegionChangchun 130023

Nucleation control is one of the key questions in quantum dots preparation and *** paper reports the experimental results of orthogonal alignment InAs islands formed on(001)InP substrate by low-pressure metal-organic chemical vapor *** a nucleation control layer,the tensile strained GaAs epilayer with orthogonal trench structure was grown firstly on(001)InP substrate under Stranski-Krastanov growth ***,the InAs islands were grown selectively on the trench edges by using strain *** growth technique results in the formation of orthogonal alignment InAs islands without any preprocessing technique prior to the growth.

关键词： trench InP alignment

Pollution sources of atmospheric fine particles and secondary aerosol characteristics in Beijing

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Journal of Environmental Sciences 2020年第9期32卷 91-98页

作者： Xi Zhang Kai Zhang Huiping liu Wenli Lv Masahide Aikawa bing liu Jinhe Wang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China School of Municipal and Environmental Engineering Co-Innovation Center for Green Building of Shandong ProvinceShandong Jianzhu UniversityJinan 250101China Faculty of Environmental Engineering The University of Kitakyushu1-1HibikinoWakamatsuKitakyushuFukuoka 808-0135Japan Qingdao Hongrui Electric Power Engineering Consulting Co. LtdQingdao 266100China Resources and Environment Innovation Research Institute School of Municipal and Environmental EngineeringShandong Jianzhu UniversityJinan 250101China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China

To investigate the secondary formation and pollution sources of atmospheric particles in urban Beijing,PM2.5 and its chemical components were collected and determined by URG-9000 D ambient ion monitor(AIM) from March 2016 to January *** water-soluble ions(WSIs), NO3-,SO42- and NH4+(SNA) had the largest proportion(77.8%) with the total concentration of 23.8 μg/***,as fine particle pollution worsened,the NO3-,SO42- and NH4+ concentrations increased basically,which revealed that secondary aerosols were the main cause of particle pollution in ***,the particle neutralization ratio(1.1),the ammonia to sulfate molar ratio(3.4) and the nitrate to sulfate molar ratio(2.2) showed that secondary aerosols are under ammonium-rich conditions with the main chemical forms of NH4 NO3 and(NH4)2 SO4,and vehicle emission could be the main anthropogenic source of secondary aerosols in *** analysis further indicated that secondary aerosols,solid fuel combustion,dust and marine aerosol were the principal pollution sources of PM2.5,accounting for about 46.1%,22.4% and 13.0%,respectively,and Inner Mongolia and Hebei Provinces could be considered as the main potential sources of PM2.5 in urban *** addition,secondary formation process was closely related with gaseous precursor emission amounts(SO2,NO2,NH3 and HONG),atmospheric ozone concentration(O3),meteorological conditions(temperature and relative humidity) and particle *** analysis of the thermodynamic equilibrium model(ISORROPIA Ⅱ)revealed that controlling total nitrate(TN) is the effective measure to mitigate fine particle pollution in Beijing.

关键词： pollution aerosol sources

Geochemical weathering of aeolian sand and its palaeoclimatic implications in the Mu Us Desert,northern China,since the Late Holocene

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Journal of Arid Land 2016年第5期8卷 647-659页

作者： liu bing JIN Heling SUN Zhong ZHAO Shuang State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Key Laboratory of Western China’s Environmental System (Ministry of Education) Lanzhou University

In the semi-arid and arid regions of northern China,geochemical behavior of the aeolian deposit is closely related to climatic and environmental changes,which was used to reconstruct the past history of environmental evolution and possibly forcing ***,the related result was still scarce due to the lack of detailed geochemical analysis results in the desert *** the present study,we systematically analyzed the geochemical components and parameters of the paleo-aeolian sand dune and modern mobile sand deposits in the Mu Us Desert and discuss the climatic variation inferred from the paleo-aeolian sand dune during the past 4.2 ka *** results indicated that （1） geochemical composition of the sandy deposits were dominated by SiO_2,Al_2O_3 and Na_2O and the deposits probably originated from the widespread upper continental crust （UCC） and were formed by long-term weathering,transport and re-deposition;（2） these sandy deposits were subjected to weaker weathering or uneven weathering under cold and dry conditions,and had highly similar material sources and degrees of weathering and leaching in general;and （3） the direct OSL （Optically Stimulated Luminescence） dating ages and geochemical parameters from the palaeosol-aeolian sand dune indicated that the regional climate change experienced several typically cold and warm *** intervals are 4.2,2.8 ka BP and Little Ice Age and Medieval Warm Period,which probably attributed to periodic variations of the Asian summer monsoonal strength and cold events of the northern Atlantic Ocean in low and high latitudes of the Northern *** results suggest that the development of the sand dune in the Mu Us Desert provided a suitable archive for understanding the past local climatic change,which is linked to the global climatic change.

关键词： climatic change geochemical component weathering degree Late Holocene Mu Us Desert

High pressure and high temperature induced polymerization of C60 quantum dots

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Chinese Physics B 2020年第2期29卷 396-400页

作者： Shi-Hao Ruan Chun-Miao Han Fu-Lu Li bing Li bing-bing liu State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012China College of Physics Changchun Normal UniversityChangchun 130032China

We synthesized C60 quantum dots(QDs) with a uniform size by a modified ultrasonic process and studied its polymerization under high pressure and high temperature(HPHT).Raman spectra showed that a phase assemblage of a dimer(D) phase(62 vol%) and a one-dimensional chain orthorhombic(O) phase(38 vol%) was obtained at 1.5 GPa and 300℃.At 2.0 GPa and 430℃,the proportion of the O phase increased to 46 vol%,while the corresponding D phase decreased to 54 vol%.Compared with bulk and nanosized C60,C60 QDs cannot easily form a high-dimensional polymeric *** fact is probably caused by the small particle size,orientation of the disordered structure of C60 QDs,and the barrier of oxide function groups between C60 *** studies enhance the understanding of the polymerization behavior of low-dimension C60 nanomaterials under HPHT conditions.

关键词： C60 quantum dots high pressure and high temperature fullerene polymer

Comparison of three evapotranspiration models with eddy covariance measurements for a Populus euphratica *** in an arid region of northwestern China

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Journal of Arid Land 2016年第1期8卷 146-156页

作者： GAO Guanlong ZHANG Xiaoyou YU Tengfei liu bing Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

The accurate estimation of evapotranspiration (ET) in arid regions is important for improving the water use efficiency of vegetation. Based on successive observations from May to October of 2014, we estimated the ET of a Populus euphratica Oliv. forest during the growing season in an extremely arid region using the PM (Penman-Monteith), SW (Shuttleworth-Wallace) and SSW (an improved canopy transpiration model) models. Estimated ET values were compared with those of the eddy covariance measurements. Results indicated that the actual ET of the P. euphratica forest was always overestimated by the PM model. The accuracy of the SW model was higher than that of the PM model. However, some data were not easily obtained because of the complicated structure of the SW model. The newly proposed SSW model gave the most accurate ET values, and its accuracy was higher at hourly than at daily time scale. In conclusion, the SSW model is more suitable for sparse vegetation system at large scales in extremely arid regions.

关键词： evapotranspiration Penman-Monteith model Shuttleworth-Wallace model SSW model