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Oxidized organic molecules in the tropical free troposphere over Amazonia

National science Review 2024年第1期11卷 174-184页

作者： Qiaozhi Zha Diego Aliaga Radovan Krejci Victoria A.sinclair Cheng Wu Giancarlo Ciarelli Wiebke scholz Liine Heikkinen Eva Partoll Yvette Gramlich Wei Huang Markus Leiminger Joonas Enroth Otso Per?kyl? Runlong Cai Xuemeng Chen Alkuin Maximilian Koenig Fernando Velarde Isabel Moreno Tuukka Pet?j? paulo Artaxo Paolo Laj Armin Hansel samara Carbone Markku Kulmala Marcos Andrade Douglas Worsnop Claudia Mohr Federico Bianchi Institute for Atmospheric and Earth system Research/Physics University of Helsinki Joint International Research Laboratory of Atmospheric and Earth system sciences Nanjing University Department of Environmental science & Bolin Centre for Climate Research Stockholm University Department of Chemistry and Molecular Biology University of Gothenburg Institute for Ion and Applied Physics University of Innsbruck Ionicon Analytik GmbH Laboratory for Atmospheric Physics Institute for Physics Research Universidad Mayor de San Andrés Institute of Physics University of Sao Paulo Institute for Geosciences and Environmental Research (IGE) University of Grenoble Alpes Agrarian sciences Institute Federal University of Uberl?ndia Beijing Advanced Innovation Center for soft Matter science and Engineering Beijing University of Chemical Technology Department of Atmospheric and Oceanic sciences University of Maryland Aerodyne Research Inc. Department of Environmental system science ETH Zürich switzerland and Laboratory of Atmospheric Chemistry Paul Scherrer Institute

New particle formation(NPF) in the tropical free troposphere(FT) is a globally important source of cloud condensation nuclei, affecting cloud properties and climate. Oxidized organic molecules(OOMs)produced from biogenic volatile organic compounds are believed to contribute to aerosol formation in the tropical FT, but without direct chemical observations. We performed in situ molecular-level OOMs measurements at the Bolivian station Chacaltaya at 5240 m above sea level, on the western edge of Amazonia. For the first time, we demonstrate the presence of OOMs, mainly with 4–5 carbon atoms, in both gas-phase and particle-phase(in terms of mass contribution) measurements in tropical FT air from Amazonia. These observations, combined with air mass history analyses, indicate that the observed OOMs are linked to isoprene emitted from the rainforests hundreds of kilometers away. Based on particle-phase measurements, we find that these compounds can contribute to NPF, at least the growth of newly formed nanoparticles, in the tropical FT on a continental scale. Thus, our study is a fundamental and significant step in understanding the aerosol formation process in the tropical FT.

关键词： oxidized organic molecules tropical aerosol formation Amazon free troposphere

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Asymmetric hydrogenation and transfer hydrogenation in the enantioselective synthesis of flavonoids

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Organic Chemistry Frontiers 2022年第4期9卷 1165-1194页

作者： Guilherme s.Caleffi Felipe C.Demidoff Carmen Najera paulo R.R.Costa Laboratorio de Quimica Bioorganica(LQB) Instituto de Pesquisas de Produtos NaturaisUniversidade Federal do Rio de JaneiroAv.Carlos Chagas Filho 373Bloco HCidade Universitaria21941-902 Rio de Janeiro Centro de Innovacion en Quimica Avanzada(ORFEO-CINQA) Universidad de AlicanteApdo.99E-03080 AlicanteSpain

Asymmetric hydrogenation(AH)and asymmetric transfer hydrogenation(ATH)are versatile synthetic methodologies widely employed in the preparation of chiral *** this review,we explore the applications of AH and ATH in the total synthesis of natural flavonoids and their analogues,highlighting the limitations and opportunities in the field.

关键词： compounds field hydrogenation

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Lanthanide-based downshifting layers tested in a solar car race

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Opto-Electronic Advances 2019年第6期2卷 1-8页

作者： sandra F.H.Correia Ana R.N.Bastos Lianshe Fu Luís D.Carlos paulo s.André Rute A.s.Ferreira Department of Physics and CICECO-Aveiro Institute of Materials University of Aveiro3810-193 AveiroPortugal Department of Electric and Computer Engineering and Instituto de Telecomunicacoes Instituto Superior TénicoUniversidade de Lisboa1049-001 LisbonPortugal Department of Electronics Telecommunications and InformaticsInstituto de TelecomunicacoesUniversity of AveiroCampus Universitário de Santiago3810-193 AveiroPortugal

The mismatch between the AM1.5G spectrum and the photovoltaic (PV) cells absorption is one of the most limiting factors for PV *** overcome this constraint through the enhancement of solar energy harvesting,luminescent downshifting (LDs) layers are very promising to shape the incident sunlight and,thus,we report here the use of Tb^3+- and eu^3+-doped organic-inorganic hybrid materials as LDs layers on si PV *** measurements on the PV cell,done before and after the deposition of the LDs layers,confirm the positive effect of the coatings on the cell’s performance in the UV spectral *** maximum delivered power and the maximum absolute external quantum efficiency increased 14% and 27%,***,a solar powered car race was organized in which the small vehicle containing the coated PV cells presented a relative increase of 9% in the velocity,when compared to that with the uncoated one.

关键词： photovoltaics downshifting layers solar car organic-inorganic hybrids lanthanide ions

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surface runoff and soil erosion in a natural regeneration area of the Brazilian Cerrado

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International soil and Water Conservation Research 2020年第2期8卷 124-130页

作者： Karina dos santos Falcao Elói Panachuki Felipe das Neves Monteiro Roniedison da silva Menezes Dulce B.B.Rodrigues Jullian souza sone paulo Tarso s.Oliveira Department of Agronomy State University of Mato Grosso do SulAgronomy DepartmentAquidauanaMS79200-000Brazil Federal University of Mato Grosso do sul CxP 549Campo GrandeMS79070-900Brazil Department of Hydraulics and sanitation Sao Carlos School of EngineeringUniversity of Sao PauloCxP.359Sao CarlosSP13566-590Brazil

The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic ***,the impacts of intense modification of land use and land cover on surface runoff and soil erosion are still poorly un-derstood in this ***,we assessed surface runoff and soil loss in a woodland Cerrado area under a former pasture area,which was abandoned and has undergone a natural regeneration process for 7 years(RC).Its results were compared with that found in an undisturbed area of woodland Cerrado(CE),40-month-old eucalyptus(3.0×1.8 m)(eu),and pasture under rotational grazing(PA).The study was conducted on Red Acrisol located in the Brazilian *** performed rainfall simulations on a plot of 0.7 m2 and using three constant rainfall intensities of 60,90,and 120 mm h-1 for 1 *** each rainfall intensity,we carried out four repetitions using different plots in each treatment,i.e.12 plots per treat-ment studied and 48 plots in *** noted that the soil physical properties were improved in RC and,consequently,water infiltration and soil erosion control;RC presented surface runoff and soil loss different from eu and PA(a=0.05).The macroporosity and soil bulk density affected surface runoff in RC and PA because the RC was used as pasture and is currently regenerating back to the cerrado *** the rainfall intensity increased,eu became more similar to PA,which showed the highest surface runoff and soil *** findings indicate that natural regeneration processes(pasture to the cerrado vegetation)tend to improve the soil ecosystem services,improving infiltration and reducing surface runoff and soil erosion.

关键词： Cerrado deforestation Forest regeneration soil erosion

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Ecosystem services of the Baltic sea:An assessment and mapping perspective

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Geography and sustainability 2020年第4期1卷 256-265页

作者： Miguel Inácio Donalda Karnauskaitė EglėBaltranaitė Marius Kalinauskas Katarzyna Bogdzevič Eduardo Gomes paulo Pereira Environmental Management Laboratory Mykolas Romeris UniversityVilniusLithuania Marine Research Institute Klaipeda UniversityKlaipedaLithuania

The Baltic sea is essential for marine ecosystem services(MEs)provision and the region’s socio-economic *** is considered one of the busiest and most polluted regional seas in *** recent years a collective effort in enforcing european and regional environmental policies and directives(*** Framework Direc-tive 2000/60/EC,2000;Marine strategy Framework Directive 2008/56/EC,2008;Maritime spatial Planning Directive 2014/89/eu,2014)has been carried *** services assessment and mapping is integrated into these *** increasing number of scientific studies,projects,and other works were developed in this context,generating a vast body of *** all efforts to improve the Baltic sea’s environmental status,the targets established were not *** is also important to analyze if current methodological approaches for assessing and mapping MEs are robust enough to provide the needed *** perspective paper analyses the status of assessment and mapping *** results showed that most of the studies were focused on qualitative assessments,with limited validation and *** the number of robust and quantitative works is increasing,more are *** is vital to carry out quantitative assessments to inform decision-makers better and standardize MEs practices across the Baltic sea.

关键词： Collaborative effort Ecological modeling Marine ecosystem services Cultural Provisioning Regulating

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Evaluation of the Implementation of a Low Emission Zone in Lisbon

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Journal of Environmental Protection 2012年第9期3卷 1188-1205页

作者： Francisco Ferreira Pedro Gomes Ana Cristina Carvalho Hugo Tente Joana Monjardino Helena Brás paulo Pereira CENsE—Center for Environmental and sustainability Research Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica Portugal DCEA-FCT/UNL—Departmento de Ciências e Engenharia do Ambiente Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa Caparica Portugal

The city of Lisbon, like many others in the eu region, introduced a Low Emission Zone (LEZ) as a tool for improving air quality in its city centre. This kind of emission reduction schemes is always controversial since it might lead to significant changes in the daily behaviours of its inhabitants. In order to evaluate the effects of the measure, an estimation of the impact of the introduction of the Lisbon LEZ was performed. Real traffic counting and fleet characterization combined with CORINAR-based emission inventory methodology allowed to estimate the impacts of three different scenarios applied to the “business as usual” condition (current vehicle fleet) ranging from “no circulation from non- compliant vehicles” to an “aggressive fleet renewal”. Results highlight the high percentage of atmospheric emissions of PM10 and NOx that might result from certain fleets like taxis and buses, especially because there was an emphasis in standardized/normalized estimations (emissions per 1000 vehicles) in order to allow different strategic approaches. The total reduction of PM10 emissions associated to each scenario vary between 6 ***-1 (scenario 2) and 8 ***-1 (scenario 1), or 25% and 34% less emissions. In terms of NOxemission reductions vary between 6 ***-1 (scenario 2) and 57 ***-1 (scenario 1), or 1% and 7% less emissions. The Lisbon LEZ is therefore much more efficient in reducing PM10 emissions compared to NOx. Major reduction in PM10 and NOx emissions are to be expected with a moderate intervention in the (relatively old) taxi fleet in Lisbon while for passenger cars the impact is limited. However in absolute terms and due to its urban mileage passenger cars should also continue being included in Lisbon LEZ. simultaneously, an effort in the increase of dedicated lanes for public transport should be made, for further reductions in PM10 and NOx emissions.

关键词： Low Emission Zone PM10 NOx euro standards

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silica matrix doped with calcium and phosphate by sol-gel

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Advances in Bioscience and Biotechnology 2010年第3期1卷 200-207页

作者： Lucimara C. Bandeira Katia J. Ciuffi paulo s. Calefi Eduardo J. Nassar 不详

silica matrices doped with calcium and phosphate at various Ca/P molar ratios were prepared by the hydrolytic sol-gel methodology. Tetraethylorthosilicate (TEOs) was reacted with calcium ethoxide, in the presence of phosphoric acid as catalyst. eu III ions were added to the resulting silica, in order to obtain structural information. The samples were dried at 50ºC and characterized before and after contact with simulated Body Fluid (sBF). The xerogels were analyzed by thermal analysis (TA), X-ray diffraction (XRD), photoluminescence (PL), and scanning electron microscopy (sEM). The PL spectra revealed eu III lines characteristic of the 5D0 ? 7FJ (J = 0, 1, 2, 3, 4) transition of this ion, and they indicated a nonhomogenous distribution of eu III in the Ca-P-si matrix. XRD and sEM confirmed the presence of an amorphous and crystalline system before and after contact of the samples with the sBF solution, and the crystalline phases were ascribed to hydroxyapatite and? ?-calcium triphosphate. The goal of the work is the preparation of a material can be used as biomaterias at low temperature.

关键词： Luminescence Biomaterials Hydroxyapatite

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Luminescent polymer electrolytes based on chitosan and containing europium triflate

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Journal of Rare Earths 2016年第7期34卷 661-666页

作者： R.Alves A.s.s.de Camargo A.Pawlicka M.M.silva Center of Chemistry University of MinhoGualtar4710-057 BragaPortugal sao Carlos Institute of Physics University of Sao Paulo13566-590 Sao Carlos-SPBrazil sao Carlos Institute of Chemistry University of Sao Paulo13566-590 Sao Carlos-SPBrazil

solid polymer electrolytes based on chitosan and europium triflate were prepared by solvent casting and characterized by X-ray diffraction, scanning electron microscopy （sEM）, atomic force microscopy （AFM）, and photoluminescence spectroscopy. The X-ray diffraction exhibited that the samples were essentially amorphous with organized regions over the whole range of the salt content studied. The AFM analysis demonstrated that the smoother sample had roughness of 4.39 nm. surface visualization through sEM revealed good homogeneity without any phase separation for more conductive samples and the less conductive showed some im- perfections on the surface. The emission and excitation spectra displayed the characteristic bands of eu（CF3sO3）3 in addition to broad bands corresponding to the polymer host. The excited state 5D0 lifetime values ranged from 0.29-0.37 ms for the studied samples.

关键词： solid polymer electrolytes natural polymers photoluminescence spectroscopy rare earths

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Performance and calibration of quark/gluon-jet taggers using 140 fb^(-1) of pp collisions at √s=13 TeV with the ATLAs detector

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Chinese Physics C 2024年第2期48卷 1-25页

作者： G. Aad B. Abbott K. Abeling N.J. Abicht s.H. Abidi A. Aboulhorma H. Abramowicz H. Abreu Y. Abulaiti B.s. Acharya C. Adam Bourdarios L. Adamczyk s.V. Addepalli M.J. Addison J. Adelman A. Adiguzel T. Adye A.A. Affolder Y. Afik M.N. Agaras J. Agarwala A. Aggarwal C. Agheorghiesei A. Ahmad F. Ahmadov W.s. Ahmed s. Ahuja X. Ai G. Aielli A. Aikot M. Ait Tamlihat B. Aitbenchikh I. Aizenberg M. Akbiyik T.P.A. Åkesson A.V. Akimov D. Akiyama N.N. Akolkar K. Al Khoury G.L. Alberghi J. Albert P. Albicocco G.L. Albouy s. Alderweireldt M. Aleksa I.N. Aleksandrov C. Alexa T. Alexopoulos F. Alfonsi M. Algren M. Alhroob B. Ali H.M.J. Ali s. Ali s.W. Alibocus M. Aliev G. Alimonti W. Alkakhi C. Allaire B.M.M. Allbrooke J.F. Allen C.A. Allendes Flores P.P. Allport A. Aloisio F. Alonso C. Alpigiani M. Alvarez Estevez A. Alvarez Fernandez M. Alves Cardoso M.G. Alviggi M. Aly Y. Amaral Coutinho A. Ambler C. Amelung M. Amerl C.G. Ames D. Amidei s.P. Amor Dos santos K.R. Amos V. Ananiev C. Anastopoulos T. Andeen J.K. Anders s.Y. Andrean A. Andreazza s. Angelidakis A. Angerami A.V. Anisenkov A. Annovi C. Antel M.T. Anthony E. Antipov M. Antonelli F. Anulli M. Aoki T. Aoki J.A. Aparisi Pozo M.A. Aparo L. Aperio Bella C. Appelt A. Apyan N. Aranzabal s.J. Arbiol Val C. Arcangeletti A.T.H. Arce E. Arena J-F. Arguin s. Argyropoulos J.-H. Arling O. Arnaez H. Arnold G. Artoni H. Asada K. Asai s. Asai N.A. Asbah J. Assahsah K. Assamagan R. Astalos s. Atashi R.J. Atkin M. Atkinson H. Atmani P.A. Atmasiddha K. Augsten s. Auricchio A.D. Auriol V.A. Austrup G. Avolio K. Axiotis G. Azuelos D. Babal H. Bachacou K. Bachas A. Bachiu F. Backman A. Badea P. Bagnaia M. Bahmani A.J. Bailey V.R. Bailey J.T. Baines L. Baines O.K. Baker E. Bakos D. Bakshi Gupta V. Balakrishnan R. Balasubramanian E.M. Baldin P. Balek E. Ballabene F. Balli L.M. Baltes W.K. Balunas J. Balz E. Banas M. Bandieramonte A. Bandyopadhyay s. Bansal L. Barak M. Barakat E.L. Barberio D. Barberis M. Barbero M.Z. Barel K.N. Barends T. Barillari M-s. Barisits T. Barklow P. Baron D.A. Baron Mo The ATLAs Collaboration

The identification of jets originating from quarks and gluons,often referred to as quark/gluon tagging,plays an important role in various analyses performed at the Large Hadron Collider,as standard Model measurements and searches for new particles decaying to quarks often rely on suppressing a large gluon-induced *** paper describes the measurement of the efficiencies of quark/gluon taggers developed within the ATLAs Collaboration,using √s=13 TeV proton–proton collision data with an integrated luminosity of 140 fb^(-1) collected by the ATLAs *** taggers with high performances in rejecting jets from gluon over jets from quarks are studied:one tagger is based on requirements on the number of inner-detector tracks associated with the jet,and the other combines several jet substructure observables using a boosted decision tree.A method is established to determine the quark/gluon fraction in data,by using quark/gluon-enriched subsamples defined by the jet *** in tagging efficiency between data and simulation are provided for jets with transverse momentum between 500 GeV and 2 TeV and for multiple tagger working points.

关键词： ATLAs JET QUARK GLUON TAGGING

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Rietveld refinement and optical properties of srWO_4:eu^(3+) powders prepared by the non-hydrolytic sol-gel method

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Journal of Rare Earths 2015年第2期33卷 113-128页

作者： P.F.s.Pereira I.C.Nogueira E.Longo E.J.Nassar I.L.V.Rosa L.s.Cavalcante Chemistry Institute University of the State of Sao Paulo Julio de Mesquita Filho-UNESP Francisco DegniAraraquara-SP 14800-900 Brazil LIEC-Chemistry Department Federal University of Sao Carlos Via Washington Luis Km 235Sao Carlos-SP 13565-905 Brazil University of Franca-UNIFRAN Via Dr.Armando Sales de OliveiraNo.201 Franca-SP 14404-600 Brazil CCN-DQ-GERATEC University of the State of Piauí Joao Cabral 2231 P.O.Box 391Terezina PI 64002-150 Brazil

We investigated the effect of annealing time on the structure and optical properties of sr WO4：eu^3＋ powders prepared by the non-hydrolytic sol-gel method and heat treated at 800 ℃ for 2,4,8 and 16 *** and differential thermal analyses revealed that sr WO4：eu^3＋ powders were obtained at about 800 ℃.X-ray diffraction patterns and Rietveld refinement data confirmed that all powders had a scheelite-type tetragonal ***-Raman and Fourier transform infrared spectra indicated structural order at short range and anti-symmetric stretching vibrations of O-W-O bonds associated with tetrahedral[WO4]*** properties were investigated by ultraviolet-visible（UV-vis）diffuse reflectance,and photoluminescence（PL）data which provided the evolution of quantum efficiency（η）and lifetime（τ）.UV-vis spectroscopy evidenced intermediate energy levels within the band gap of sr WO4：eu^3＋ *** properties validated that the eu^3＋ electric-dipole（^5D0→^7F2）transition in PL emission spectra was dominant which proved that eu^3＋ ions were positioned in a site without an inversion center.[（^5D0→^7F2）/（^5D0→^7F1）]band ratios showed that eu^3＋ ions were located in a low symmetry *** PL emission,ηandτproved the dependence on the annealing time in the behavior of sr WO4：eu3＋powders with a higher relative emission PL intensity as well as higherηandτvalues related to other samples when heat treated at 800℃ for 8 h.

关键词： srWO4 Rietveld refinement optical band gap eu^(3+) +-rare earth luminescence

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