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Effects of typical algae species（Aphanizomenon flosaquae and Microcystis aeruginosa） on photoreduction of Hg2+ in water body

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Journal of Environmental Sciences 2019年第11期31卷 9-16页

作者： Rongguo Sun Yafei Mo Xinbin Feng Leiming Zhang Lin Jin Qiuhua Li State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China School of Chemistry and Material Guizhou Normal University Guiyang China Air Quality research Division Science and Technology Branch Environment and Climate Change Canada Toronto Ontario Canada

Photoreduction characteristics of divalent inorganic mercury (Hg2+) in the presence of specific algae species are still not well *** experiments were conducted in the present study to identify the effects of different concentrations of living/dead algae species,including Aphanizomenon flosaquae (AF) and Microcystis aeruginosa (MA),on the photoreduction rate of Hg2+ under various light *** experimental results showed that percentage reduction of Hg2+ was significantly influenced by radiation wavelengths,and dramatically decreased with the presence of *** highest percentage reduction of Hg2+ was induced by UV-A,followed by UV-B,visible light and dark for both living and dead AF,and the order was dark > UV-A > UV-B > visible light for both living and dead *** were two aspects,i.e.,energy and attenuation rate of light radiation and excrementitious generated from algae metabolisms,were involved in the processes of Hg2+ photoreduction with the presence of algae under different light *** percentage reduction of Hg2+ decreased from 15% to 11% when living and dead AF concentrations increased by 10 times (from 106 to 105 cells/mL),and decreased from11% to ~9% in the case of living and dead MA *** can adsorb Hg2+ and decrease the concentration of free Hg2+,thus inhibiting Hg2+ photoreduction,especially under the conditions with high concentrations of *** significant differences were found in percentage reduction of Hg2+ between living and dead treatments of algae *** results are of great importance for understanding the role of algae in Hg2+ photoreduction.

关键词： Aphanizomenon flosaquae Microcystis aeruginosa Photoreduction Divalent inorganic mercury (Hg2+)

Integrating WSN and Laser SLAM for Mobile Robot Indoor Localization

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Computers, Materials & Continua 2023年第3期74卷 6351-6369页

作者： Gengyu Ge Zhong Qin Xin Chen School of Information Engineering Zunyi Normal UniversityZunyi563006China School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing400065China

Localization plays a vital role in the mobile robot navigation system and is a fundamental capability for the following path planning *** an indoor environment where the global positioning system signal fails or becomes weak,the wireless sensor network(WSN)or simultaneous localization and mapping(SLAM)scheme gradually becomes a research hot *** method uses received signal strength indicator(RSSI)values to determine the position of the target signal node,however,the orientation of the target node is not ***,the distance error is large when the indoor signal receives *** laser SLAM-based method usually uses a 2D laser Lidar to build an occupancy grid map,then locates the robot according to the known grid ***,this scheme only works effectively in those areas with salient geometrical *** traditional particle filter always fails for areas with similar structures,such as a long *** solve their shortcomings,this paper proposes a novel coarse-to-fine paradigm that uses WSN to assist mobile robot localization in a geometrically similar ***,the fingerprints database is built in the offline stage to get reference distance *** distance data is determined by the statistical mean value of multiple RSSI ***,a hybrid map with grid cells and RSSI values is constructed when the mobile robot moves from a starting point to the ending ***,the RSSI values are thought of as a basic reference to get a coarse ***,an improved particle filteringmethod is presented to achieve fine *** results demonstrate that our approach is effective and robust for global *** localization success rate reaches 97.0%and the average moving distance is only 0.74 meters,while the traditional method always *** addition,the method also works well when the mobile robot is kidnapped to another position in the environment.

关键词： Robot localization SLAM WSN RSSI geometrically similar environment particle filter

Dynamic Analysis of Some Impulsive Fractional-Order Neural Network with Mixed Delay

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Journal of Donghua university(English Edition) 2015年第1期32卷 86-90页

作者：刘向虎刘衍民李艳芳 School of Mathematics and Computer Science Zunyi Normal College

In this paper,the authors study some impulsive fractionalorder neural network with mixed delay. By the fractional integral and the definition of stability, the existence of solutions of the network is proved,and the sufficient conditions for stability of the system are presented. Some examples are given to illustrate the main results.

关键词： fractional-order neural network mixed delay fixed point theorem

A Toy Model for Estimation of the Event Plane Non-Flat Effect on an Elliptic Flow in Heavy Ion Collision

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Chinese Physics Letters 2014年第7期31卷 59-63页

作者：周凤雏蔡勖周代翠 College of Physics and Electronics Science Guizhou Normal University Guiyang 550001 Institute of Particle Physics Central China Normal University Wuhan 430079

In heavy ion collision, the event plane is a key parameter defined as the plane composted by the impact parameter b and beam axis z, It is a crucial reference for various observables, which focus on the initial spatial anisotropy of the overlap region in heavy ion collision. We notice that in some recent heavy ion collision experiments, due to potentially inefficient or even the invalidity of experimental facilities, the reconstructed event plane, which is used in elliptic flow study, may be biased towards a non-flat distribution. In this study, we develop a toy model for fast estimation of the bias effect and its influence on the elliptic flow. The possible azimuthal bias of the detector is firstly studied by varying the part of its azimuthal information. We also study on the limit acceptance of the detector, which will be used to measure the particle of interest in an elliptic flow. The outcomes are presented by comparing the flow study results with or without the non-flat effect on the event plane.

关键词： HEAVY ion collisions PARAMETER estimation ANISOTROPY AZIMUTH MATHEMATICAL models

ON A CLASS OF DOUGLAS FINSLER METRICS

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Acta Mathematica Scientia 2018年第2期38卷 695-708页

作者：朱红梅 College of Mathematics and Information Science Henan Normal University

In this article, we study a class of Finsler metrics called general （α, β）-metrics, which are defined by a Riemannian metric α and a 1-form β. We determine all of Douglas general （α, β）-metrics on a manifold... 详细信息

关键词： Finsler metric general (α, β)-metric Douglas metric

Preparation of pistachio shell-based porous carbon and its adsorption performance for low concentration CO_(2)

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Particuology 2024年第12期95卷 103-114页

作者： Yuhua Zhang Yanmei Jin Song Li Hong Wu Huijuan Luo School of Chemistry and Materials Engineering Liupanshui Normal UniversityLiupanshuiChina guizhou Province Key Laboratory of Clean Coal Utilization LiupanshuiChina guizhou Coal Product Quality Supervision&Inspection Institute Liupanshui553001China

In this study,high-performance porous carbon for CO_(2) adsorption was synthesized from pistachio shells and modified with urea to enrich nitrogen content in the porous *** effects of activation temperature,KOH-to-carbon ratio,and urea addition on the pore structure and CO_(2) adsorption capacity of the porous carbon were *** was conducted using N2 adsorption-desorption isotherms,scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and Fourier-transform infrared spectroscopy(FT-IR).Results showed that under preparation conditions of 700℃,KOH-to-carbon ratio of 2,and 15 wt%urea concentration,the synthesized GAC-15-2-700 porous carbon exhibited a maximum specific surface area of 1395 m^(2)/g,micropore volume of 0.505 cm^(3)/g,and N-5 peak area ratio of 65.57%.It achieved a CO_(2) adsorption capacity of 3.56 mmol/*** functional groups on the porous carbon primarily existed as pyridinic N(N-6),pyrrolic/pyridinic N(N-5),and quaternary N(N-Q),with the enriched micropores and high N-5 content being crucial for CO_(2) adsorption.

关键词： Pistachio shells Porous carbon CO_(2)adsorption

Effects of Elevated CO_2 Concentration on the Biomasses and Nitrogen Concentrations in the Organs of Sainfoin(Onobrychis viciaefolia Scop.)

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Agricultural Sciences in China 2009年第4期8卷 424-430页

作者： ZHOU Zheng-chao SHANGGUAN Zhou-ping College of Tourism and Environmental Sciences Shaanxi Normal University Xi＇an 710062 P.R. China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling 712100 P.R. China

In forage grasses, the nitrogen concentration is directly related to the nutritional value. The studies examined the hypothesis that global elevation of CO2 concentration probably affects the biomass, nitrogen （N） concentration, and allocation and distribution patterns in the organs of forage grasses. While sainfoin （Onobrychis viciaefolia Scop.） seedlings grew on a low nutrient soil in closed chambers for 90 days, they were exposed to two CO2 concentrations （ambient or ambient＋350 μmol mol^-1 CO2） without adding nutrients to them. After 90 days exposure to CO2, the biomasses of leaves, stems, and roots, and N concentrations and contents of different parts were measured. Compared with the ambient CO2 concentration, the elevated CO2 concentration increased the total dry matter by 25.07%, mainly due to the root and leaf having positive response to the elevated CO2 concentration. However, the elevated CO2 concentration did not change the proportions of the dry matters in different parts and the total plants compared with the ambient CO2 concentration. The elevated CO2 concentration lowered the N concentrations of the plant parts. Because the dry matter was higher, the elevated CO2 concentration had no effect on the N content in the plants compared to the ambient CO2 concentration. The elevated CO2 concentration promoted N allocations of the different parts significantly and increased N allocation of the underground part. The results have confirmed the previous suggestions that the elevated CO2 concentration stimulates plant biomass production and decreases the N concentrations of the plant parts.

关键词： biomass CO2 N allocation N content C/N ratio sainfoin

Cosmological scenario based on particle creation and holographic equipartition

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Chinese Physics C 2020年第6期44卷 162-168页

作者： Fei-Quan Tu Yi-Xin Chen Qi-Hong Huang School of Physics and Electronic Science Zunyi Normal UniversityZunyi 563006China Zhejiang Institute of Modern Physics Zhejiang UniversityHangzhou 310027China

We propose a cosmological scenario that describes the evolution of the universe based on particle creation and holographic equipartition. The model attempts to solve the inflation of the early universe and the accelerated expansion of the present universe without introducing the dark energy from the thermodynamical *** the evolution of the universe, we assume that the universe consistently creates particles, and that the holographic equipartition is always satisfied. Further, we set the creation rate of particles proportional to H^2 in the early universe and to H in the present and late universe, where H depicts the Hubble parameter. Consequently, we obtain the solutions a(t) ∝ e^αt/3 and a(t) ∝ t^1/2 for the early universe and solutions a(t) ∝ t^δ and a(t) ∝ e^Ht for the present and late universe, respectively, where α and δ are the parameters. Finally, we obtain and analyze two important thermodynamic properties for the present model.

关键词： particle creation holographic equipartition non-equilibrium thermodynamics

A comparison of Ce^(3+) luminescence in X_2Z(BO_3)_2(X=Ba,Sr;Z=Ca,Mg) with relevant composition and structure

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Journal of Rare Earths 2012年第1期30卷 1-5页

作者：林惠红梁宏斌张国斌陶冶 Department of Chemistry Hanshan Normal University MOE Laboratory of Bioinorganic and Synthetic Chemistry State Key Laboratory of Optoelectronic Materials and TechnologiesSchool of Chemistry and Chemical EngineeringSun Yat-sen University National Synchro-tron Radiation Laboratory University of Science and Technology of China Beijing Synchrotron Radiation Facilities Institute for High Energy Physics

The VUV-UV spectroscopic properties of Ce3＋ in Ba2Mg（BO3）2,Ba2Ca（BO3）2 and Sr2Mg（BO3）2 were compared,and the relation between the energy of the 4f→5d transition of Ce3＋ and the coordination environments of substituted alkaline earth ions was *** chromaticity coordinates of Ce3＋ activated X2Z（BO3）2（X=Ba,Sr;Z=Ca,Mg） phosphors were changeable from blue to whitish and further to green range by varying the doping concentration of Ce3＋ or the types of substituted alkaline earth ions upon 172 nm excitation.

关键词： luminescence Ce3+ Sr2Mg(BO3)2 Ba2Mg(BO3)2 Ba2Ca(BO3)2 rare earths