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Seasonal variability in cDOM absorption and fluorescence properties in the Barataria Basin,Louisiana,Usa

Journal of environmental Sciences 2010年第10期22卷 1481-1490页

作者： Shatrughan Singh eurico D'sa erick Swenson Department of Oceanography and coastal Sciences Louisiana State University

Absorption and fluorescence properties of chromophoric dissolved organic matter （cDOM） along a 124 km transect in the Barataria Basin, a large estuary located in Louisiana, Usa, were investigated during high and low flow periods of the Mississippi River in the spring and winter of 2008-2009. Mean cDOM absorption at 355 nm from the marine to the freshwater end member stations ranged from （3.25 ± 0.56） to （20.76 ± 2.43） m^-1 for the three month high flow period whereas it varied from （1.48 ± 1.08） to （25.45 ± 7.03） m^-1 for the same stations during low flow period. corresponding salinity values at these stations indicated the influence of river and shelf exchanges in the lower basin and precipitation and runoff in the upper basin. An inverse relationship of cDOM absorbance and fluorescence with salinity observed in the basin could he a useful indicator of salinity. cDOM fluorescence also varied over a large range showing an approximately 8 to 12-fold increase between the marine and freshwater end members for the two flow seasons. excitation-emission matrix spectral plots indicated the presence of various fluorescence components with highest being the A-peak, lowest the T-peak, and the c and M-peaks showing similar trends along the transect. During low flow season the A/c ratio were well correlated with station locations indicating increased terrestrial influence towards the upper basin. cDOM absorption and fluorescence at 355 nm were highly correlated and independent of cDOM sources suggesting that fluorescence could be used to characterize cDOM in the basin.

关键词： Barataria Basin chromophoric dissolved organic matter cDOM fluorescence excitation-emission matrix

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electronic properties and photodegradation ability of Nd-TiO_(2)for phenol

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Journal of Rare earths 2022年第7期40卷 1063-1072页

作者： Zhimin Zhao Jinjia Liu gala sa Aiju Xu Inner Mongolia Key Laboratory of Green catalysis College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHohhot 010022China State Key Laboratory of coal conversion Institute of Coal Chemistry Chinese Academy of SciencesTaiyuan 030001China National energy center for coal to clean Fuels Synfuels China Co.Ltd.Beijing 101400China

In this study,the photocatalytic activity of Nd-TiO_(2)photocatalysts obtained by common hydrothermal method was evaluated by practical experiments and theoretical calculations based on density functional theory(DFT).The synthesized photocatalysts were characterized by X-ray diffraction(XRD),N_(2)adsorption-desorption,Fourier transform infrared spectroscopy(FT-IR),high resolution transmission electron microscopy(HRTeM),X-ray photoelectron spectroscopy(XPS),UV-Vis diffuse reflectance spectroscopy(DRS),and photoluminescence(PL)to study their physical/chemical prope *** the same time,the photoelectronic performance was also *** photodegradation ability of asprepared photocatalysts and the effect of Nd doped amount and photocatalysts dosage were investigated by the photodegradation of phenol(30 mg/L)under 400 W metal halide lamp(UV-Vis).The effect of Nd on electronic properties of TiO_(2)and adsorption ability of phenol were *** show the red-shift wavelength of 0.5 mol%Nd-TiO_(2),indicating that its absorption capacity is stronger than pristine TiO_(2)in the same wavelength *** result of DFT calculations demonstrates that the optical bandgap of Nd-TiO_(2)is profoundly reduced,thus the light absorption ability is promoted,which will be responsible for the enhanced photocatalytic performance of Nd-TiO_(2).0.5 mol%Nd is an optimum value for photodegradation phenol,and phenol can be completely degraded by 0.5 mol%Nd-TiO_(2)for 210 min,the higher catalytic performance is derived from the efficient separation of e-/h+***,the adsorption energy calculations of phenol on TiO_(2)(101)and Nd-TiO_(2)(101)demonstrate that the Nd doping can significantly enhance the adsorption ability of phenol on catalyst surfaces because of the formation of Nd-O *** last,the stability measurement through four recycles exhibits that 0.5 mol%Nd-TiO_(2)possesses excellent stability.

关键词： TiO_(2) Hydrothermal method Density functional theory Phenol Photodegradation Rare earths

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Labeled yon Neumann Architecture for Software-Defined cloud

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Journal of computer Science & Technology 2017年第2期32卷 219-223页

作者： Yun-gang Bao sa Wang, Member, ccF State Key Laboratory of computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China University of chinese Academy of Sciences Beijing 100049 China

As cloud computing is moving forward rapidly, cloud providers have been encountering great challenges： long tail latency, low utilization, and high interference. They intend to co-locate multiple workloads on a single server to improve the resource utilization. But the co-located applications suffer from severe performance interference and long tail latency, which lead to unpredictable user experience. To meet these challenges, software-defined cloud has been proposed to facilitate tighter coordination among application, operating system and hardware. Users＇ quality of service （QoS） requirements could be propagated all the way down to the hardware with differential management mechanisms. However, there is little hardware support to maintain and guarantee users＇ QoS requirements. To this end, this paper proposes Labeled von Neumann Architecture （LvNA）, which introduces a labelling mechanism to convey more software＇s semantic information such as QoS and security to the underlying hardware. LvNA is able to correlate labels with various entities, e.g., virtual machine, process and thread, and propagate labels in the whole machine and program differentiated services based on rules. We consider LvNA to be a fundamental hardware support to the software-defined cloud.

关键词： software-defined cloud von Neumann architecture tail latency performance interference

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Quaternionic Monge–Ampère Measure on Pluripolar Set

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Acta Mathematica Sinica,english Series 2024年第6期40卷 1431-1457页

作者： Hichame AMAL saïd ASSeRDA Fadoua BOUKHARI Department of Mathematics Laboratory LaREAMIRegional Centre of Trades of Education and TrainingKenitraMorocco Ibn Tofail University Faculty of SciencesDepartment of MathematicsPO 242 KenitraMorroco

In this paper, we prove that in a hyperconvex domain Ω in H^(n), if a non-negative Borel measure is dominated by a quaternionic Monge–Ampère measure, then it is a quaternionic Monge–Ampère measure of a function i... 详细信息

关键词： Quaternion space Monge-Amp`ere operator plurisubharmonic function

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Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2011年第9期12卷 665-679页

作者： Med Amine LARIBI Lotfi ROMDHANe sad ZeGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with Denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （ga） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RScR and RSPc （R： revolute; S： spherical; c： cylindrical; P： prismatic）, have illustrated the application of the ga to solve the problem of function generation and path generation. In some cases, the ga method becomes trapped in a local minimum. A combined ga-fuzzy logic （ga-FL） method is then used to improve the final result. The results show that gas, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (ga-FL) method Denevit-Hartenberg parameters Mechanism synthesis

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Diversity of endophytes across the soil-plant continuum for Atriplex spp. in arid environments

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Journal of Arid Land 2016年第2期8卷 241-253页

作者： Mohammad e TAHTAMOUNI sa'eb KHResaT Mary LUceRO Jesus SIgaLA Adrian UNc New Mexico State University Department of Plant & Environmental Sciences Las Cruces NM 88003 USA Jordan University of Science and Technology Department of Natural Resources and Environment Irbid 22110 Jordan Seco Spice Chamberino NM 88027 USA Boreal ecosystems Research Initiative Memorial University of Newfoundland Corner Brook A2H 5G4 Canada University of Leeds School of Geography Leeds LS2 9JT UK

endophytes are hypothesized to be transferred across the soil-plant continuum, suggesting both the transfers of endophytes from environment to plant and from plant to soil. To verify this hypothesis and to assess the role of locality, we evaluated the similarity of microbial communities commonly found both in soils and endophytic communities in three arid regions, i.e. the Jornada LTeR （Long Term ecological Research） site in New Mexico, Usa, and the research station of Jordan University of Science and Technology （JUST） and Khanasd research station in Badia region of Jordan. Rhizosphere and non-rhizosphere soils, leaves and seeds of Atriplex spp. were sampled. Diversity and distribution of bacteria and fungi across the soil-plant continuums were assessed by tag-encoded FLX amplicon pyrosequencing and sequence alignment. Of the total bacterial OTUs （operational taxonomic units）, 0.17% in Khanasri research station, 0.16% in research station of JUST, and 0.42% in Jornada LTeR site were commonly found across all the plant and soil compartments. The same was true for fungi in two regions, i.e. 1.56% in research station of JUST and 0.86% in Jornada LTeR site. However, in Khanasri research station, 12.08% of total fungi OTUs were found in at least one soil compartment and one plant compartment. Putative Arthrobacter, Sporosarcina, cladosporium and members of Proteobacteria and Actinobacteria were found across all the soil-plant continuums. Ascomycota, mainly including Didymellaceae, Pleosporaceae and Davidiellaceae were present across all the soil-plant continuums. Microbial communities in two regions of Jordan were similar to each other, but both of them were different from the Jornada LTeR site of Usa. SIMPeR （similarity percentage） analysis of bacterial and fungal taxa for both soil and endophyte communities revealed that dissimilarities of two bacterial genera （Arthrobacter and Sporosarcina） and two fungal genera （cladosporium and Alternaria） are very high, so they play

关键词： endophytes microbial diversities soil-plant continuum pyrosequencing Atriplex spp.

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can the desiccation of forests in Tara National Park (Serbia) be attributed to the effects of a drought period?

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Journal of Forestry Research 2024年第6期35卷 220-229页

作者： GoranČešljar NevenaČule IlijaĐorđević saša eremija Natalija Momirović Marko Tomić Filip Jovanović Institute of Forestry Kneza Višeslava 3Belgrade 11030Serbia Tara National Park Milenka Topalovića 3Bajina Bašta 31250Serbia

Forest ecosystems within national parks are threatened by various biotic and abiotic *** deter-mine the causes of the desiccation and death of trees in mixed coniferous and deciduous forests of Tara National Park(TNP),Serbia,we monitored defoliation and mortality of individual trees in permanent experimental *** on the desiccation of a large number of trees were gathered by determining the total volume of dry trees and areas of forests under drying *** two sets of data were combined to determine the impact of climatic events,primarily drought periods,on the desiccation of *** data from the International co-operative Program on Assessment and Monitoring of Air Pollution effects on Forests(IcP Forests)with TNP data helped relate forest desiccation to climate *** climate signals were identified by monitoring tree defoliation changes in two permanent experimental plots,and then assessed for their influence on tree desicca-tion in the entire national *** standardized precipita-tion evapotranspiration index(SPeI)was used for a more detailed analysis of the drought *** the lack of climate data for a certain period,the SPeI index revealed a link between climate variables and the defoliation and desic-cation of ***,the desiccation of trees was preceded by a long drought *** mixed conifer-ous-deciduous forests are often considered less vulnerable to natural influences,this study suggests that forest ecosystems can become vulnerable regardless of tree species composi-tion due to multi-year *** findings contribute to a better understanding of important clues for predicting pos-sible future desiccation of *** monitoring of the state of forests and of more permanent experimental plots in national parks could provide better quality data and timely responses to stressful situations.

关键词： Forest ecosystems extreme climate events Drought Defoliation Monitoring

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POSITIVe SOLUTIONS FOR SINGULAR BVPs ON THe POSITIVe HALF-line ARISING FROM ePIDeMIOLOGY AND cOMBUSTION THeORY

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Acta Mathematica Scientia 2012年第2期32卷 672-694页

作者： Smaïl Djebali Ouiza saïfi 闫宝强 Department of Mathematics E.N.S.P.O.Box 9216050 Kouba.AlgiersAlgeria Department of economics Faculty of Economic and Management SciencesAlgiers UniversityAlgeria Department of Mathematics Shandong Normal University

In this work, we are concerned with the existence and multiplicity of positive solutions for singular boundary value problems on the half-line. Two problems from epi- demiology and combustion theory set on the positive half-line are investigated upper and lower solution techniques combined with fixed point index on cones in priate Banach spaces. The results complement recent ones in the literature. We use appropriate Banach spaces. The results complement recent ones in the literature.

关键词： Fixed points index positive solution singular problem cone lower andupper solution half-line

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Kinetic modeling of high-temperature oxidation of pure Mg

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Journal of Magnesium and Alloys 2020年第3期8卷 819-831页

作者： sa Ma Fangzhou Xing Na Ta Lijun Zhang State Key Laboratory of Powder Metallurgy Central South UniversityChangshaHunan 410083P.R.China Max-Planck-Institut fiir eisenforschung GmbH Max-Planck-Straβe 140237DusseldorfGermany

A variety of experimental tracer diffusivities of Mg and O in magnesium oxide available in the literature were first *** mobilities including bulk and short-circuit diffusion of Mg and O were then obtained by means of the cALPHAD(calculation of Phase Diagram)***,the diffusion-controlled kinetic model of oxidation in a gas-MgO-Mg environment was developed based on the moving boundary model and Fick's law,coupling with the modified thermodynamic description of MgO.A mathematical expression for parabolic rate constant kp of the oxide scale was derived for magnesia and correlated with the thermodynamic and diffusion kinetic *** evaluated kp results were in line with the experimental ***,the oxidation process of pure magnesium at 673 K was model-predicted,and the predicted evolution of the oxide thicknesses agreed very well with the experimental *** was indicated that the grain boundaries diffusion of magnesium cations predominated the high temperature oxidation process.

关键词： MgO Diffusion Oxidation Atomic mobility cALPHAD Wagner's model

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Intelligent Resource Allocations for Software-Defined Mission-critical IoT Services

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computers, Materials & continua 2022年第11期73卷 4087-4102页

作者： chaebeen Nam sa Math Prohim Tam Seokhoon Kim Department of Software convergence Soonchunhyang UniversityAsan31538Korea Department of computer Software engineering Soonchunhyang UniversityAsan31538Korea

Heterogeneous Internet of Things(IoT)applications generate a diversity of novelty applications and services in next-generation networks(NGN),which is essential to guarantee end-to-end(e2e)communication resources for both control plane(cP)and data plane(DP).Likewise,the heterogeneous 5th generation(5G)communication applications,including Mobile Broadband communications(MBBc),massive Machine-Type commutation(mMTc),and ultra-reliable low latency communications(URLLc),obligate to perform intelligent Quality-of-Service(QoS)class Identifier(QcI),while the cP entities will be suffered from the complicated massive HIOT ***,the existing management and orchestration(MANO)models are inappropriate for resource utilization and allocation in large-scale and complicated network *** cope with the issues mentioned above,this paper presents an adopted software-defined mobile edge computing(SDMec)with a lightweight machine learning(ML)algorithm,namely support vector machine(SVM),to enable intelligent MANO for real-time and resource-constraints IoT applications which require lightweight computation ***,the SVM algorithm plays an essential role in performing QcI ***,the software-defined networking(SDN)controller allocates and configures priority resources according to the SVM classification ***,the complementary of SVM and SDMec conducts intelligent resource MANO for massive QcI environments and meets the perspectives of mission-critical communication with resource constraint *** on the e2e experimentation metrics,the proposed scheme shows remarkable outperformance in key performance indicator(KPI)QoS,including communication reliability,latency,and communication throughput over the various powerful reference methods.

关键词： Mobile edge computing Internet of Things software defined networks traffic classification machine learning resource allocation

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