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Seasonal Development of Microbial Activity in Soils of northern norway

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Pedosphere 2005年第6期15卷 716-727页

作者： M. bLTER n. SOETHE R. HORn c. UHLIG Institut für Polarkologie Christian-Albrechts-Universitt zu Kiel Wischhofstr. 1-3 D-24148 Kiel (Germany). de Institut für Pflanzenernhrung und bodenkunde Christian-Albrechts-Universitt zu Kiel Olshausenstr. 40 D-24098 Kiel (Germany) Holt Research centre The Norwegian Crop Research Institute N-9292 Tromsφ(Norway)

Seasonal development of soil microbial activity and bacterial biomass in sub-polar regions was investigated to determine the impacts of biotic and abiotic factors, such as organic matter content, temperature and moisture. The study was performed during spring thaw from three cultivated meadows and two non-cultivated forest sites near Alta, in northern norway. Samples from all five sites showed increasing respiration rates directly after the spring thaw with soil respiration activity best related to soil organic matter content. However, distributions of bacterial biomass showed fewer similarities to these two parameters. This could be explained by variations of litter exploitation through the biomass. Microbial activity started immediately after the thaw while root growth had a longer time lag. An influence of root development on soil microbes was proposed for sites where microorganisms and roots had a tight relationship caused by a more intensive root structure. Also a reduction of microbial activity due to soil compaction in the samples from a wheel track could not be observed under laboratory conditions. new methodological approaches of differential staining for live and dead organisms were applied in order to follow changes within the microbial community. Under laboratory conditions freeze and thaw cycles showed a damaging influence on parts of the soil bacteria. Additionally, different patterns for active vs. non-active bacteria were noticeable after freeze-thaw cycles.

关键词： bacterial biomass freezing microbial activity soil compaction thawing

Structural and Optical Properties of Graphene Oxide Prepared by Modified Hummers’Method

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computers, Materials & continua 2016年第6期52卷 175-185页

作者： n.Selvakumar Uday Pradhan S.b.Krupanidhi Harish c.barshilia nanomaterials Research Lab Surface Engineering DivisionCSIR-National Aerospace LaboratoriesBangalore-560017India Materials Research center Indian Institute of ScienceBangalore-560012India

Graphene oxide was synthesized from graphite flakes using modified Hummers’*** interlayer spacings of graphite,graphite oxide and graphene oxide were measured using X-ray diffraction *** c/O atomic ratios of graphite oxide and graphene oxide were calculated from XPS *** transformation of graphite to graphite oxide and finally to graphene oxide was clearly observed from the micro-Raman spectroscopy data and was confirmed from the FESEM ***-VIS-nIR spectrophotometer was used to study the absorbance of graphene oxide and reduced graphene oxide ***,the chemically reduced graphene oxide was heat-treated in air to obtain chemically modified graphene.

关键词： Graphene oxide Graphite,modified Hummers’method thermal annealing optical properties

Field topologies in ideal and near-ideal magnetohydrodynamics and vortex dynamics

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Science china(Physics,Mechanics & Astronomy) 2015年第1期58卷 12-31页

作者： LOW b.c. High Altitude Observatory National Center for Atmospheric Research

Magnetic field topology frozen in ideal magnetohydrodynamics （MHD） and its breakage in near-ideal MHD are reviewed in two parts, clarifying and expanding basic concepts. The first part gives a physically complete description of the frozen field topology derived from magnetic flux conservation as the fundamental property, treating four conceptually related topics： Eulerian and La- grangian descriptions of three dimensional （3D） MHD, chandrasekhar-Kendall and Euler-potential field representations, magnetic helicity, and inviscid vortex dynamics as a fluid system in physical contrast to ideal MHD. A corollary of these developments clar- ifies the challenge of achieving a high degree of the frozen-in condition in numerical MHD. The second part treats field-topology breakage centered around the Parker Magnetostatic Theorem on a general incompatibility of a continuous magnetic field with the dual demand of force-free equilibrium and an arbitrarily prescribed, 3D field topology. Preserving field topology as a global con- straint readily results in formation of tangential magnetic discontinuities, or, equivalently, electric current-sheets of zero thickness. A similar incompatibility is present in the steady force-thermal balance of a heated radiating fluid subject to an anisotropic thermal flux conducted strictly along its frozen-in magnetic field in the low-fl limit. In a weakly resistive fluid the thinning of current sheets by these general incompatibilities inevitably results field notwithstanding the small resistivity. Strong Faraday in sheet dissipation, resistive heating and topological changes in the induction drives but also macroscopically limits this mode of energy dissipation, trapping or storing free energy in self-organized ideal-MHD structures. This property of MHD turbulence captured by the Taylor hypothesis is reviewed in relation to the Sun＇s corona, calling for a basic quantitative description of the breakdown of flux conservation in the low-resistivity li

关键词： magnetic topology magnetic reconnection current sheets magnetic helicity thermal conduction solar corona magnetohy-drodynamics interstellar clouds

Magnetically propelled carreau fluid flow over penetrable sensor surface influenced by thermal radiation,Joule heating and heat generation

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communications in Theoretical Physics 2022年第2期74卷 9-18页

作者： b J Gireesha b nagaraja n Srikantha n G Rudraswamy A Felicita Department of Studies and Research in Mathematics Kuvempu UniversityShankaraghattaShivamoggaKarnatakaIndia Department of Mathematics MS Ramaiah Institute of TechnologyBangaloreIndia Department of Mathematics P.C.Jabin Science College(Autonomous)HubballiIndia

This examination emphasizes the analysis of thermal transmission of carreau fluid flow on a permeable sensor surface equipped with radiation,Joule heating,an internal heat source,and a magnetic *** the above effects and assumptions,the equations that administer the flow are formulated.A configured system of equations is productively reduced to a system of ordinary differential *** reduced system is then dealt with using the Runge–Kutta-Fehlberg fourth–fifth order tool equipped by the shooting *** numerical solutions are utilized to plot graphs and *** conclusion of the study outlines some important findings such as the power law index,the thermal radiation parameter and the heat source parameter enhance the thermal panel whereas the Weissenberg number deescalates the *** power law index and permeable velocity decrease the velocity panel *** representation of streamlines of the flow has been given to strengthen the study.A detailed description has been produced about the results obtained in the study.

关键词： sensor surface carreau fluid squeezed flow thermal radiation heat generation

3D LASER ScAnnInG FOR PRESERVATIOn AnD STRUcTURAL MOnITORInG OF HISTORIc cALIFORnIA ADObE MISSIOnS

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Journal of Green building 2016年第4期11卷 1-14页

作者： H.M.böttger c.J.Arce bazán n.P.Saarman Assistant Professor Architecture&Community Design ProgramDepartment of Art+ArchitectureUniversity of San FranciscoUSA

At the University of San Francisco Architecture&community Design Program,the Architectural Engineering curriculum utilizes a Leica ScanStation c103D Laser Scanner to document historic structures and monitor their structural *** of the oldest structures in the State of california are the historic adobe missions built by native Americans and Spanish catholic missionaries between 1769 and *** is a region of very high seismic activity,and the adobe structures have withstood significant earthquakes and other erosive or destructive forces over their ***,they are sensitive structures in need of active preservation and very few original adobe buildings *** together with local structural engineers who specialize in seismic restoration of historic adobe structures,USF students have conducted laser scanning at Mission Santa cruz and Mission San Miguel Arcángel,creating extensive 3D point cloud records,and developing architectural drawings which establish the current state of these structures for the purposes of historic preservation and structural *** of the delicate and irregular nature of these structures,the 3D laser scanner is the most appropriate tool for detailed yet non-invasive *** in 1821,Mission San Miguel Arcángel suffered significant damage in the nearby 2003 San Simeon *** original adobe structure has undergone partial repairs such as banding at the top of the walls of the *** the 3D laser scanner,thorough scans are stitched together to create full interior and exterior 3D point cloud files,which are processed in Leica cyclone and Autodesk Recap,and then imported into AutocAD to create detailed line drawings of plans,elevations and sections of significant *** lean and other indicators of crack progress and deterioration are areas of special *** these records,a structural monitoring program has begun to document the condition of the buildings in wet seaso

关键词： 3D laser scanning adobe seismic engineering education california missions 1

Magnetohydrodynamic flow and heat transfer of a hybrid nanofluid over a rotating disk by considering Arrhenius energy

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communications in Theoretical Physics 2021年第4期73卷 9-20页

作者： M Gnaneswara Reddy naveen Kumar R b c Prasannakumara n G Rudraswamy K Ganesh Kumar Department of Mathematics Acharya Nagarjuna University CampusOngole-523001India Department of Studies and Research in Mathematics Davangere UniversityShivagangothriDavangere-577007KarnatakaIndia Department of Mathematics P.C.Jabin Science CollageHubballi-580031India

This research work explores the effect of hybrid nanoparticles on the flow over a rotating disk by using an activation energy ***,we considered molybdenum disulfide and ferro sulfate as nanoparticles suspended in base fluid *** magnetic field is pragmatic normal to the hybrid nanofluid flow *** derived nonlinear ordinary differential equations are non-dimensionalized and worked out numerically with the help of Maple software by the RKF-45 *** scientific results for a non-dimensionalized equation are presented for both nanoparticle and hybrid nanoparticle *** of various predominant restrictions on flow and thermal fields are *** estimation for friction factor,local nusselt number and Sherwood number are also *** reveal that the reduction of the heat transfer rate is greater in hybrid nanoparticles when compared to nanoparticles for increasing values of Eckert number and the thermal field enhances for the enhanced values of volume fraction.

关键词： porous medium MHD hybrid nanoparticles activation energy

A comprehensive Survey on Federated Learning Applications in computational Mental Healthcare

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computer Modeling in Engineering & Sciences 2025年第1期142卷 49-90页

作者： Vajratiya Vajrobol Geetika Jain Saxena Amit Pundir Sanjeev Singh Akshat Gaurav Savi bansal Razaz Waheeb Attar Mosiur Rahman brij b.Gupta Institute of Informatics and communication University of DelhiDelhi110021India Maharaja Agrasen college University of DelhiDelhi110096India computer Engineering Ronin InstituteMontclairNJ 07043USA Department of Research and Innovation Insights2TechinfoJaipur302001India University centre for Research and Development(UcRD) Chandigarh UniversityChandigarh140413India Management Department College of Business AdministrationPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia ccRI&Department of computer Science and Information Engineering Asia UniversityTaichung413Taiwan Symbiosis centre for Information Technology(ScIT) Symbiosis International UniversityPune411057India center for Interdisciplinary Research University of Petroleum and Energy Studies(UPES)Dehradun248007India

Mental health is a significant issue worldwide,and the utilization of technology to assist mental health has seen a growing *** aims to alleviate the workload on healthcare professionals and aid *** applications have been developed to support the challenges in intelligent healthcare ***,because mental health data is sensitive,privacy concerns have *** learning has gotten some *** research reviews the studies on federated learning and mental health related to solving the issue of intelligent healthcare *** explores various dimensions of federated learning in mental health,such as datasets(their types and sources),applications categorized based on mental health symptoms,federated mental health frameworks,federated machine learning,federated deep learning,and the benefits of federated learning in mental health *** research conducts surveys to evaluate the current state of mental health applications,mainly focusing on the role of Federated Learning(FL)and related privacy and data security *** survey provides valuable insights into how these applications are emerging and evolving,specifically emphasizing FL’s impact.

关键词： Depression emotional recognition intelligent healthcare systems mental health federated learning stress detection sleep behaviour

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： n c ROY M R TALUKDER A n cHOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh bangladesh council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(ROS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Shape of the geometrically active atomic states of carbon

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chinese Physics b 2010年第2期19卷 219-224页

作者：熊庄 bacalis n.c. AMS Research center Southeast University Theoretical and Physical chemistry Institute National Hellenic Research FoundationVasileos Constantinou 48AthensGreece 11635

We have developed a computer code for {／em ab initio} the variational configuration interaction calculation of the electronic structure of atoms via variationally optimized Lagurre type orbitals, treating the orbital effective charges as variational parameters. Excited states of the same symmetry, in order to avoid the inherent restrictions of the standard method of Hylleraas--Unheim and MacDonald, are computed variationally by minimizing the recently developed minimization functionals for excited states. by computing, at the minimum, the one-electron density and the probability distribution of the two-electron angle, and the most probable two-electron angle, we investigate the atomic states of the carbon atom. We show that, without resorting to the （admittedly unproven） concept of hybridization, as an intrinsic property of the atomic wave function, the most probable value of the two-electron angle is around the known angles of carbon bonding, i.e. either 109^／circ or 120^／circ or 180^／circ, depending on each low-lying state of the bare carbon atom.

关键词： carbon hybridization excited states variational principle