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Aromatic compound degradation by iron reducing bacteria isolated from irrigated tropical paddy soils

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Journal of Environmental Sciences 2008年第12期20卷 1487-1493页

作者： w.Reichardt University of the Philippines at Diliman(UPD) Marine Science InstituteBolinao Marine Laboratory(BML)-UP Guiguiwanen RdBolinaoThe Philippines

Forty-six candidate phenol/benzoate degrading-iron reducing bacteria were isolated from long term irrigated tropical paddy soils by enrichment *** cultures and some prepared mixed cultures were examined for ferric oxide reduction and phenol/benzoate *** the isolates were iron reducers,but only 56.5%could couple iron reduction to phenol and/or benzoate degradation,as evidenced by depletion of phenol and benzoate after one week *** of degradative capability using Biolog...

关键词： aromatic compounds degradation iron reducing bacteria paddy soil

Effects of site productivity on individual tree maximum basal area growth rates of Eucalyptus pilularis in subtropical Australia

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Journal of Forestry Research 2023年第6期34卷 1659-1668页

作者： P.w.west Forest Research Centre Southern Cross UniversityLismoreNSW 2480Australia

Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal *** any tree size,this maximum increased as site productivity ***,the size at which this maximum occurred decreased as productivity *** research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive *** trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth *** was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive *** model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests.

关键词： Growth model Individual tree Maximum growth rate Eucalyptus pilularis Physiological eff ects

Applications of Chapman-Richards model to geotechnical engineering

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1286-1292页

作者： w.Nie w.Guo School of Civil Engineering Nanyang Technical UniversitySingapore Key Laboratory of Coast Civil Structure and Safety of Ministry of Education Tianjin UniversityTianjinChina School of Civil Engineering Tianjin UniversityTianjinChina

In this paper,the Chapman-Richards model is adapted to best fit three types of nonlinear curves that are generally encountered in geotechnical engineering practices,*** degree of consolidation versus time factor curves in one-dimensional consolidation and plane strain consolidation under strip loading,the compressibility and permeability curves of soft clay,and the geometry parameters of geosynthetic tube versus pumping pressure *** methods of determining unknown parameters using the Chapman-Richards model are fully *** is found that the Chapman-Richards model has its range of applications in geotechnical engineering and may provide unique insights into the complexity of geotechnical problems.

关键词： Mathematical modeling Chapman-Richards model Curve-fitting

Adventures Beyond Amdahl's Law:How Power-Performance Measurement and Modeling at Scale Drive Server and Supercomputer Design

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Journal of Computer Science & Technology 2023年第1期38卷 80-86页

作者： Kirk w.Cameron Computer Science Virginia TechWashington D.C.VA 24061U.S.A.

Amdahl’s Law painted a bleak picture for large-scale *** implication was that parallelism was limited and therefore so was potential *** Amdahl’s contribution was seminal and important,it drove others vested in parallel processing to define more clearly why large-scale systems are critical to our future and how they fundamentally provide opportunities for speedup beyond Amdahl’s *** the early 2000s,much like Amdahl,we predicted dire consequences for large-scale systems due to power *** our early work was often dismissed,the implications were clear to some:power would ultimately limit *** this retrospective,we discuss how power-performance measurement and modeling at scale led to contributions that have driven server and supercomputer design for more than a *** the influence of these techniques is now indisputable,we discuss their connections,limits and additional research directions necessary to continue the performance gains our industry is accustomed to.

关键词： Amdahl’s Law speedup power-aware computing power modeling performance modeling performance prediction power measurement

Three subspecies of Black-tailed Godwit share non-breeding sites in the world's largest river delta

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Avian Research 2025年第01期 1-10页

作者： Delip K.Das wouter M.G.Vansteelant Bingrun Zhu Shariful Islam Naim Khandakar Marco van der Velde Chris J.Hassell Jesse R.Conklin Pierrick Bocher Jos C.E.w.Hooijmeijer Yvonne I.Verkuil Theunis Piersma Department of Zoology Faculty of Life and Earth Sciences Jagannath University Conservation Ecology Group Groningen Institute for Evolutionary Life Sciences University of Groningen Bird Eyes Centre for Global Ecological Change at the Faculties of Science & Engineering and Campus Fryslan University of Groningen Theoretical and Computational Ecology Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Hunan Global Messenger Technology Co. Ltd Behavioural & Physiological Ecology Groningen Institute for Evolutionary Life Sciences University of Groningen Global Flyway Network Littoral Environnement et Sociétés UMR LIENSs 7266 CNRS La Rochelle University NIOZ Royal Netherlands Institute for Sea Research Department of Coastal Systems

During the non-breeding season(September–April), Black-tailed Godwits(Limosa limosa) are commonly seen in coastal and inland wetlands of the Ganges-Brahmaputra-Meghna Delta in Bangladesh. we hypothesize that the Ganges-Brahmaputra-Meghna Delta, at the overlap between the Central Asian and East Asian–Australasian flyways, may host three subspecies that breed in disjunct areas of temperate and northern Asia: L. l. limosa, L. l. melanuroides, and L. l. bohaii. we used mitochondrial DNA(mt DNA) haplotype network and biometric analysis to determine subspecies in captured individuals, and deployed GPS–GSM transmitters to verify breeding areas of individuals with subspecies assignments. To test for differential habitat preferences, we sampled birds at two ecologically distinct habitats known to host the largest concentrations of non-breeding Black-tailed Godwits in Bangladesh: Nijhum Dweep National Park, a tidal coastal habitat with brackish water on the south-central coast, and Tanguar Haor(‘backmarsh'), a seasonal freshwater floodplain in the north. During the non-breeding seasons of 2021–2022 and 2022–2023, we sampled and measured 93 Black-tailed Godwits, 54 of which were equipped with GPS–GSM transmitters. Our mt DNA haplotype network analysis confirmed the presence of limosa, melanuroides, and bohaii subspecies at the study sites. Thus, indeed, Black-tailed Godwits subspecies, despite having distinct breeding ranges, exhibit(partially) overlapping non-breeding ranges in Asia. The subspecies composition differed significantly between sites, with limosa and bohaii dominating in Tanguar Haor and melanuroides in Nijhum Dweep. Of the 21 individuals that were tracked to their breeding grounds, 18 migrated to the expected breeding range of their respective subspecies. However, one bird with a limosa haplotype migrated to a known breeding area of bohaii, whereas two birds with melanuroides haplotypes migrated to the supposed breeding range of limosa. Therefore, while ecologic

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Limits on light emission from silicon

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Chinese Optics Letters 2009年第4期7卷 268-270页

作者： Peter würfel Institut für Angewandte Physik Universitt KarlsruheD-76128 KarlsruheGermany

Although silicon is an indirect semiconductor, light emission from silicon is governed by the same gener- alized Planck＇s radiation law as the emission from direct semiconductors. The emission intensity is given by the absorptance of the volume in which there is a difference of the quasi Fermi energies. A difference of the Fermi energies may result h＇om the absorption of external light （photoluminescence） or from the injection of electrons and holes via selective contacts （electroluminescence）. The quantum efficiency may be larger than 0.5 for carrier densities below 10^15 cm^-3. At larger densities, non-radiative recombination, in particular Auger recombination dominates. At all carrier densities, the relation between emission intensity and difference of the quasi Fermi energies is maintained. Since this difference is equal to the voltage of a properly designed solar cell, luminescence is the key indicator of material quality for solar cells.

关键词： Carrier concentration Fermi level Light Light emission Photoluminescence Semiconducting silicon Silicon

The QT interval in Parkinson′s disease:a systematic review

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Journal of Geriatric Cardiology 2024年第9期21卷 855-864页

作者： Simon w Rabkin Division of Cardiology University of British ColumbiaVancouverBC V5Z 1M9Canada

Background PD(PD)is associated with a twofold increase in the risk of death especially sudden death.A predisposing factor for cardiac sudden death is prolongation of the QT *** study evaluated the potential association between QT interval and *** A systematic search was conducted of Medline and EMBASE using the search terms“PD”AND“QT interval”OR“Cardiac Repolarization”to identify *** Seven studies with persons with PD(n=981)and control groups were *** was a significant difference in QT interval comparing patients with PD and persons without *** odds ratio showed a significant(Pwas a significantly longer QT in patients with PD than controls of 10.7±2.8 *** analysis did not show much publication *** only on studies that related the QT interval to the severity of PD as assessed by Hoehn–Yahr classification(n=6),there was a significant(P=0.004)overall correlation between QT interval and the severity of *** was little publication *** data directly examining patients with PD taking any drug than might prolong QT do not support an association between these mediations and QT *** Individuals with PD have a longer QT interval than individuals without *** QT interval is associated with a greater severity of PD and a greater probability of developing more severe *** QT interval should be considered in assessment of PD and possibly as a target for the treatment of PD.

关键词： QT QTc Focus

PREDICTION OF CHARACTERISTICS FOR VERTICAL ROUND NEGATIVE BUOYANT JETS IN HOMOGENEOUS AMBIENT

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Journal of Hydrodynamics 2001年第1期13卷 103-110页

作者： Huai, w.X. Li, w. Dep. of River Eng. Coll. of Water Resource Eng. Wuhan 430072 China

The k-Ε turbulence model is used to establish a mathematical model of a vertical round jet with negative buoyancy in a static homogeneous ambient. The hybrid finite analytic method, with a non-uniform staggered grid, is used to calculate the whole flow field. The variations of centerline velocity, density and turbulent kinetic energy along the axial line for a given exit densimetric Froude number are found to converge to single curves under the unified scaling law derived by Chen and Rodi. The profiles of mean velocities, mean density difference and the half-width of negative buoyant jets for velocity and density are given. The calculation confirmed that the maximum height of rise is proportional to M03/4 B0-1/2, where M0 and B0 are the momentum flux and the buoyancy flux at the source, respectively.

关键词： Computer simulation Jets Mathematical models Numerical methods

Superexchange and charge transfer in the nickelate superconductor La_(3)Ni_(2)O_(7) under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 1-8页

作者： wéi wú Zhihui Luo Dao-Xin Yao Meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Recently, a bulk nickelate superconductor La_(3)Ni_(2)O_(7) is discovered at pressures with a remarkable high transition temperature T_(c)~ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La_(3)Ni_(2)O_(7),by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d_(3z^(2)-r^(2)) and O-p_(z) orbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-d_(x^(2)-y^(2)) and O-p_(x)/p_(y) orbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the d_(x^(2)-y^(2)) and p_(x)/p_(y) orbitals, whereas the d_(3z^(2)-r^(2)) and p_(z) orbitals retain underdoped. we propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La_(3)Ni_(2)O_(7) superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo