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Organic matter quality of forest floor as a driver of C and P dynamics in acacia and eucalypt plantations established on a Ferralic Arenosols, Congo

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Forest Ecosystems 2020年第3期7卷 511-525页

作者： Lydie-stella Koutika Lorenzo Cafiero Annamaria Bevivino Agustín Merino Research Centre on the Durability and the Productivity of Industrial Plantations(CRDPI) Av.Ma Loango Moe Poaty BP 1291Pointe-NoireRepublic of the Congo Department for sustainability Biotechnologies and Agroindustry DivisionLaboratory for AgriFood SustainabilityQuality and SafetyItalian National Agency for New TechnologiesEnergy and Sustainable Economic DevelopmentENEACasaccia Research CentreVia Anguillarese301-00123RomeItaly Department for sustainability Division Resource EfficiencyLaboratory Technologies for the ReuseRecyclingRecovery and valorisation of Waste and MaterialsItalian National Agency for New TechnologiesEnergy and Sustainable Economic DevelopmentENEACasaccia Research Centre00123RomeItaly Department of soil science and Agricultural Chemistry University of Santiago de Compostela2702LugoSpain

Background: Land-use change and forest management may alter soil organic matter(sOM) and nutrient dynamics,due in part to alterations in litter input and quality. Acacia was introduced in eucalypt plantations established in the Congolese coastal plains to improve soil fertility and tree growth. Eucalypt trees were expected to benefit from n2 fixed by acacia. However, some indicators suggest a perturbation in sOM and P dynamics might affect the sustainability of the system in the medium and long term. In tropical environments, most of the nutrient processes are determined by the high rates of organic matter(OM) mineralization. Therefore, sOM stability might play a crucial role in regulating soil-plant processes. In spite of this, the relationship between sOM quality, C and other nutrient dynamics are not well understood. In the present study, OM quality and P forms in forest floor and soil were investigated to get more insight on the C and P dynamics useful to sustainable management of forest ***: Thermal analysis(differential scanning calorimetry(DsC) and thermogravimetry(TGA)) and nuclear magnetic resonance(solid state13 C CPMAss and nMR and31 P-nMR) spectroscopy have been applied to partially decomposed forest floor and soils of pure acacia and eucalypt, and mixed-species acacia-eucalypt ***: Thermal analysis and13 C nMR analysis revealed a more advanced stage of humification in forest floor of acacia-eucalypt stands, suggesting a greater microbial activity in its litter. sOM were related to the OM recalcitrance of the forest floor, indicating this higher microbial activity of the forest floor in this stand might be favouring the incorporation of C into the mineral ***: In relation with the fast mineralization in this environment, highly soluble orthophosphate was the dominant P form in both forest floor and soils. However, the mixed-species forest stands immobilized greater P in organic forms, preventing the P losses by lea

关键词： Mixed-species plantations soil chemical stability Organic P Forest ecosystems Potential climate change mitigation

Efficient mid-infrared single-photon detection using superconducting nbTin nanowires with high time resolution in a Gifford-McMahon cryocooler

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Photonics Research 2022年第4期10卷 1063-1070页

作者： Jin Chang Johannes W.n.Los Ronan Gourgues stephan steinhauer s.n.Dorenbos silvania F.Pereira HPaul Urbach Val Zwiller Iman Esmaeil Zadeh Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands single Quantum B.V. Delft 2628 CJThe Netherlands KTH Royal Institute of Technology Department of Applied PhysicsAlbanova University Centre10691 StockholmSweden

shortly after their inception, superconducting nanowire single-photon detectors(snsPDs) became the leading quantum light detection technology. With the capability of detecting single-photons with near-unity efficiency,high time resolution, low dark count rate, and fast recovery time, snsPDs outperform conventional single-photon detection techniques. However, detecting lower energy single photons(ncy and low timing jitter has remained a challenge. To achieve unity internal efficiency at mid-infrared wavelengths, previous works used amorphous superconducting materials with low energy gaps at the expense of reduced time resolution(close to a nanosecond), and by operating them in complex milli Kelvin(mK) dilution refrigerators. In this work,we provide an alternative approach with snsPDs fabricated from 5 to 9.5 nm thick nbTin superconducting films and devices operated in conventional Gifford-McMahon cryocoolers. By optimizing the superconducting film deposition process, film thickness, and nanowire design, our fiber-coupled devices achieved >70% system detection efficiency(sDE) at 2 μm and sub-15 ps timing jitter. Furthermore, detectors from the same batch demonstrated unity internal detection efficiency at 3 μm and 80% internal efficiency at 4 μm, paving the road for an efficient mid-infrared single-photon detection technology with unparalleled time resolution and without mK cooling requirements. We also systematically studied the dark count rates(DCRs) of our detectors coupled to different types of mid-infrared optical fibers and blackbody radiation filters. This offers insight into the trade-off between bandwidth and DCRs for mid-infrared snsPDs. To conclude, this paper significantly extends the working wavelength range for snsPDs made from polycrystalline nbTin to 1.5–4 μm, and we expect quantum optics experiments and applications in the mid-infrared range to benefit from this far-reaching technology.

关键词： nanowires technology snsPD

Enhancement of photocatalytic and photoelectrochemical properties of TiO_(2) nanotubes sensitized by sILAR-Deposited Pbs nanoparticles

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Journal of Materiomics 2020年第1期6卷 62-69页

作者： A.Hajjaji s.Jemai A.Rebhi K.Trabelsi M.Gaidi A.n.Alhazaa M.A.Al-Gawati M.A.El Khakani B.Bessais Laboratoire de Photovoltaique Centre de Recherches et des Technologies de L’EnergieTechnopole de Borj-CedriaBP 952050Hammam-LifTunisia Institut national de La Recherche scientifique INRS-EnergieMateriaux et Telecommunications1650Blvd.Lionel-BouletVarennesQCJ3X-1S2Canada Center of Advanced Materials Research Research Institute of Sciences and Engineering University of SharjahPO Box 27272SharjahUnited Arab Emirates Research Chair for Tribology Surface and Interface SciencesDepartment of Physics and AstronomyCollege of ScienceKing Saud UniversityRiyadhSaudi Arabia King Abdullah Institute for nanotechnology(KAIn) King Saud UniversityRiyadhSaudi Arabia school of Design Engineering Universitat Politecnica de ValenciaCamide VeraSpain

The aim of this work is to improve the photocatalytic and photoelectrochemical properties of TiO_(2) nanotubes(TiO_(2)-nTAs)by sensitizing them with Pbs nanoparticles(nPs)prepared by the successive Ionic Layer Adsorption and Reaction method(sILAR).The Microstructure,surface morphology,phase composition and optical properties of the prepared structure were characterized using X-ray diffraction(XRD),scanning electron microscopy(sEM),transmission electron microscopy(TEM and High-resolution mode HRTEM)and X-ray photoelectron spectroscopy(XPs).The TiO_(2) nTAs were loaded by Pbs nPs,which contents increase by increasing the number of sILAR *** Pbs nPs,which have a size in the order of ~20 nm,were found to be uniformly distributed in the TiO_(2) nTAs without damaging the tubular ordered *** photocatalytic activity of the Pbs/TiO_(2) nTAs system,toward Amido Black(AB),showed significant enhancement compared to the bare untreated TiO_(2) *** 30 sILAR deposition cycles the Pbs-nPs/TiO_(2) nTAs structure is able to remove 75% of BA under simulated solar light,considerably higher than the 40% removal obtained with unloaded TiO_(2) nTAs.A significant improvement of the Photoelectrochemical(PEC)efficiency has been also demonstrated for the Pbs-nPs/TiO_(2) nTAs hybrid *** improvement is mainly related to visible-light harvesting and reduced recombination of photo-generated electron-hole pairs due to the synergistic effect of the heterojunction and to the wellorganized morphology of the TiO_(2) nTAs.

关键词： TiO_(2)nanotubes Pbs nanoparticles Amido black degradation Photoelectrochemical performance

seismic fragility assessment of RC frame structure designed according to modern Chinese code for seismic design of buildings

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 331-342页

作者： D. Wu s. Tesfamariam s.F. stiemer D. Qin Key Laboratory of Earthquake Engineering and Applied Technique of Guangdong Province Guangzhou 501405 China school of Engineering University of British Columbia Kelowna V1 V 1 V7 Canada Dept. of Civil Engineering University of British Columbia Vancouver V6T 1Z4 Canada Dept. of Civil Engineering Radio Film and Television Design and Research Institute Beijing 100045 China

Following several damaging earthquakes in China, research has been devoted to find the causes of the collapse of reinforced concrete （RC） building sand studying the vulnerability of existing buildings. The Chinese Code for seismic Design of Buildings （CCsDB） has evolved over time, however, there is still reported earthquake induced damage of newly designed RC buildings. Thus, to investigate modern Chinese seismic design code, three low-, mid- and high-rise RC frames were designed according to the 2010 CCsDB and the corresponding vulnerability curves were derived by computing a probabilistic seismic demand model （PsDM）.The PsDM was computed by carrying out nonlinear time history analysis using thirty ground motions obtained from the Pacific Earthquake Engineering Research Center. Finally, the PsDM was used to generate fragility curves for immediate occupancy, significant damage, and collapse prevention damage levels. Results of the vulnerability assessment indicate that the seismic demands on the three different frames designed according to the 2010 CCsDB meet the seismic requirements and are almost in the same safety level.

关键词： building damage criteria collapse ratio probabilistic seismic demand model (PsDM) fragility curves Chinese Code for seismic Design of Buildings (CCsDB)

Cross-sections of photonuclear reactions ^(65)Cu(γ, n)^(64)Cu and ^(63)Cu(γ, xn)^(63−x)Cu in the energy range E_(γmax) = 35–94 MeV

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Chinese Physics C 2022年第12期46卷 208-216页

作者： O.s.Deiev I.s.Timchenko s.M.Olejnik s.M.Potin V.A.Kushnir V.V.Mytrochenko s.A.Perezhogin B.I.shramenko national science Center“Kharkov Institute of Physics and Technology” 1Akademichna St.61108KharkivUkraine

The flux-averaged cross-sectionsfor the reactions^(65)Cu(γ,n)^(64)Cu,^(63)Cu(γ,n)^(62)Cu,^(63)Cu(γ,2n)^(61)Cu,and^(63)Cu(γ,3n)^(60)Cu have been measured within the bremsstrahlung end-point energy E_(γmax)range of 35–94 *** experiments were performed with the electron beam from the nsC KIPT linear accelerator LUE-40 with the use of the activation and off-lineγ-ray spectrometric *** calculation of the flux-average cross-sections_(th)was conducted using the cross-sectionσ(E)values from the TALYs1.95 code,run with default *** is shown that the experimental average cross-sections for the reactions^(65)Cu(γ,n)^(64)Cu,^(63)Cu(γ,n)^(62)Cu,and^(63)Cu(γ,2n)^(61)Cu are systematically higher than the theoretical estimates based on the TALYs1.95 *** obtaineds supplement the data of different laboratories for the(γ,n)and(γ,2n)reactions of^(63)Cu and^(65)*** the reaction^(63)Cu(γ,3n)^(60)Cu,the values ofwere measured for the first time.

关键词： ^(63)Cu ^(65)Cu photonuclear reactions flux-averaged cross-section bremsstrahlung end-point energies of 35-94 MeV activation and off-lineγ-ray spectrometric techniques TALYs1.95 GEAnT4

novel strategies for Preparation and Characterization of Functional Polymer-metal nanocomposites for Electrochemical Applications

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复旦学报（自然科学版） 2007年第5期46卷 630-631页

作者： D.n.Muraviev Department of Chemistry Autonomous University of Barcelona08193 BellaterraBarcelona Spain

1 Introduction The synthesis and characterization of Metal nanoParticles (MnPs) has attracted great interest of scientists and technologists within the last years due their unique physical and chemical properties,which substantially differ from those of both bulk material and single *** properties provide various practical applications of MnPs including catalysis-and electrocatalysis-based processes,which occur in,for example,fuel cells of different types or in various sensing devices (***...

关键词： novel strategies polymer-metal nanocomposites

synthesis, Characterization, Thermal stability and Antibacterial Activity of Coumarin Based Methacrylate Copolymers

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Chinese Journal of Polymer science 2014年第10期32卷 1373-1380页

作者： s. Venkatesan B. Ranjithkumar s. Rajeshkumar K. Anver Basha P.G. & Research Department of Chemistry C. Abdul Hakeem College Hakeem Nagar Melvisharam-632509Tamil Nadu India Department of Biochemistry Adhiparasakthi College of Arts and Science Kalavai-632506 Vellore Dt TamilNadu India

Monomer of 7-methacryloyloxy-4-methylcoumarin （MAOMC） was synthesized and characterized by FTIR, 1H-nMR and 13C-nMR spectroscopy. Copolymers of MAOMC with butoxyethylmethacrylate （BOEMA） at different feed compositions were prepared by free radical solution polymerization at （70 ± 1） ℃ in ethylmethylketonc （EMK） using benzyl peroxide （BPO） as an initiator. The copolymers were characterized by FTIR and IH-nMR spectroscopy. Thermogravimetric analysis （TGA） and differential scanning calorimetry （DsC） of the copolymers showed moderate thermal stability and higher Tg values. Gel permeation chromatography （GPC） was used to find out the molecular weights of the different copolymers. Antibacterial activities of the copolymers were also investigated against the selected pathogenic bacteria＇s. The antibacterial activity of the copolymer increases as the MAOMC content increases in the copolymer. This shows that coumarin moiety plays a very important role in the antibacterial activity.

关键词： 7-Methacryloyloxy-4-methylcoumarin Copolymerization Thermogravimetric analysis Antibacterial activity

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Renal dopaminergic system:Pathophysiological implications and clinical perspectives

作者： n.s.·沃什顿(n.s. Washton)

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World Journal of nephrology 2015年第2期4卷 196-212页

作者： Marcelo Roberto Choi nicolás Martín Kouyoumdzian natalia Lucía Rukavina Mikusic María Cecilia Kravetz María Inés Rosón Martín Rodríguez Fermepin Belisario Enrique Fernández Department of Anatomy and Histology Faculty of Pharmacy and BiochemistryUniversity of Buenos AiresCONICETINFIBIOC Department of Pathophysiology Faculty of Pharmacy and BiochemistryUniversity of Buenos AiresCONICETINFIBIOC

Fluid homeostasis, blood pressure and redox balance in the kidney are regulated by an intricate interaction between local and systemic anti-natriuretic and natriuretic systems. Intrarenal dopamine plays a central role on this interactive network. By activating specifc receptors, dopamine promotes sodium excretion and stimulates anti-oxidant and anti-inflammatory pathways. Different pathological scenarios where renal sodium excretion is dysregulated, as in nephrotic syndrome, hypertension and renal infammation, can be associated with impaired action of renal dopamine including alteration in biosynthesis, dopamine receptor expression and signal transduction. Given its properties on the regulation of renal blood fow and sodium excretion, exogenous dopamine has been postulated as a potential therapeutic strategy to preventrenal failure in critically ill patients. The aim of this review is to update and discuss on the most recent findings about renal dopaminergic system and its role in several diseases involving the kidneys and the potential use of dopamine as a nephroprotective agent.

关键词： Dopamine Hypertension kidney na+, K+-ATPase sodium Oxidative stress D1 receptors D2 receptors Renal failure Edema