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Journal of Advanced Ceramics 2016年第2期5卷 103-110页

作者： Y.f.GOMES A.K.fREITAS R.M.NASCIMENTO M.R.D.BOMIO C.A.PASKOCIMAS f.v.motta Departamento de Engenharia de Materiais Universidade Federal do Rio Grande do Norte 59078-900 Natal/RN Av.Sen.Salgado Filho 3000 CEP 59072-970 Brazil

In this study, the nanostructures of pure ZnO and ZnO:xCe3+ were prepared using statistic design—factorial design 3(3?1)?3-level and mixed-level factorials and fractional with replicates in the central point, totaling 11 experiments. The experiments were performed using the microwave-assisted hydrothermal (MAH) method with Ce3+ concentration of 2 and 4 mol% at 60, 110, and 160 °C for 10, 20, and 30 min. X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical diffuse reflectance were used to characterize the products. The fractional factorial design indicated the optimal design area, and the studies were continued by ridge analysis. The analysis of variance (ANOvA), the Pareto, and the model adjusted to the conditions proposed in this study due to the determination coefficient of 99.9%, variance (R 2), and response surface generated were satisfactory, thus having an optimization in the process of obtaining ZnO doped with Ce.

关键词： hydrothermal ZnO cerium photocatalytic activity factorial design 3(3-1)

Red-emitting CaWO4:Eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution

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Journal of Rare Earths 2022年第2期40卷 226-233,I0002页

作者： L.X.Lovisa I.M.P.da Silva A.A.G.Santiago M.Siu Li E.Longo C.A.Paskocimas M.R.D.Bomio f.v.motta Institute of Physics and Chemistry.federal University of Itajubd(UNIfEI) ItajubdMG37500-903Brazil LSQM-Laboratory of Chemical Synthesis of Materials-Department of Materials Engineering Federal University of Rio Grande Do NorteP.O.Box 152459078-900Natal RNBrazil IfSC USPAv.Trabalhador Sao Carlense400CEP 13566-590Sao CarlosSPBrazil CDMf-LIEC UFSCarP.O.Box 67613565-905Sao Carlos.SPBrazil

CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(MAH).The phase formation,morphology,luminescent properties and ene rgy transfer were *** X-ray diffraction(XRD)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary *** growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of *** luminescence spectra of CaWO_(4):Eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 D0→7 f2(Eu^(3+))transition at 624 *** feature signals dominant behavior of the electric dipole *** presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 f3 and 3 H6→3 *** parameters are discussed to characterize CaWO_(4):Eu^(3+),Tm^(3+)*** study of the emission spectrum as a function of the concentration of Eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):Eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIE value of x=0.63 and y=*** photoluminescence results show 97%high color purity for CaWO_(4):4 mol%Eu^(3+),a high CRI(92%)and a low CCT of 1085 *** results demonstrate that the CaWO_(4):Eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices.

关键词： CaWO_(4):Eu^(3+),Tm^(3+)microwave-assisted hydrothermal method Photoluminescence Red phosphor Rare earths

Effect of different starting materials on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)

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Journal of Advanced Ceramics 2015年第1期4卷 65-70页

作者： P.N.MEDEIROS v.D.ARAÚJO A.P.A.MARQUES R.L.TRANQUILIN C.A.PASKOCIMAS M.R.D.BOMIO J.A.vARELA E.LONGO f.v.motta DEMAT CTUFRNAv.Sen.Salgado Filho3000CEP 59072-970 NatalRNBrazil UACSA UFRPEBR 101 Sul5225CEP 54510-000 Cabo de Santo AgostinhoPEBrazil UNIfESP Rua Prof.Artur Riedel275CEP 09972-270 DiademaSPBrazil dLIECIQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazil LIEC IQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazi

Literature has reported the synthesis of barium calcium titanates by various synthesis methods such as solid state reaction,co-precipitation and polymer *** compounds are usually obtained using calcium carbonate(CaCO_(3)),barium carbonate(BaCO3)and titanium oxide as starting *** study investigated the effect of different starting reagents on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)(BCT)by complex polymerization method(CPM).Two sets of starting precursors were used:titanium citrate,CaCO_(3)and BaCO3,and titanium citrate and Ba1-xCaxCO3 solid solution *** were crystallized at a temperature range from 400℃to 700℃for different *** obtained powders were characterized by X-ray diffraction(XRD),thermogravimetry(TG)and differential thermal analysis(DTA),and Raman and infrared *** infrared spectroscopy indicated that the chelation processes of Ba,Ca,Ti and CA ions are very *** results showed that the use of CaCO_(3)and BaCO3 or Ba1-xCaxCO3 solid solution as precursors does not affect the final properties of BCT powders obtained by CPM.

关键词： ceramic synthesis Ba_(0.8)Ca_(0.2)TiO_(3)(BCT) complex polymerization method(CPM)

Influence of variables on the synthesis of Cofe_(2)O_(4)pigment by the complex polymerization method

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Journal of Advanced Ceramics 2015年第2期4卷 135-141页

作者： P.N.MEDEIROS Y.f.GOMES M.R.D.BOMIO I.M.G.SANTOS M.R.S.SILvA C.A.PASKOCIMAS M.S.LI f.v.motta Department of Materials Engineering Federal University of Rio Grande do NorteCampus Lagoa NovaCEP 59078-900-Natal/RNBrazil Department of Chemistry Federal University of ParaíbaCidade UniversitáriaCEP 58051-900-João Pessoa/PBBrazi Institute Physics of São Carlos USPCEP 13566-590São CarlosSão PauloBrazil

Synthetic inorganic pigments are most widely used in ceramic applications due to their excellent chemical and thermal stability and their lower toxicity to both human and environment as *** the present work,black ceramic pigment Cofe_(2)O_(4)has been synthesized by the complex polymerization method(CPM)with good chemical *** order to study the influence of variables on the process of obtaining pigment through CPM,2^((5-2))fractional factorial design with resolution III was *** variables studied in the mathematical modeling were:citric acid/metal concentration,pre-calcination time,calcination temperature,calcination time,and calcination *** pigments were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and Uv-visible(Uv-vis)*** on the results,the formation of cobalt ferrite phase(Cofe_(2)O_(4))with spinel structure was *** color of pigments obtained showed dark shades,from black to *** model adjusted to the conditions proposed in this study due to the determination coefficient of 99.9%and variance(R²)showed that all factors are significant at the confidence level of 95%.

关键词： pigment complex polymerization method(CPM) fractional factorial design

Alternative stable states in mountain forest ecosystems： the case of European larch(Larix decidua) forests in the western Alps

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Journal of Mountain Science 2017年第5期14卷 811-822页

作者： Jose v.MORIS Giorgio vACCHIANO Davide ASCOLI Renzo motta University of Turin DISAFALargo Paolo Braccini 210095 Grugliasco(TO)Italy

European larch(Larix decidua) forests of the western Alps form extensivecultural landscapes whose resilience to global changes is currently unknown. Resilience describes the capacity of ecological systems to maintain the same state, i.e., the same function, processes, structure, and composition despite disturbances, environmental changes and internal fluctuations. Our aim is to explore the resilience of larch forests to changes in climate and land use in the western Italian *** do so, we examined whether larch forests can be described as an alternative stable state in mountain forest ecosystems. We used tree basal area data obtained from field forest inventories in combination with topography, forest structure, land use, and climate information. We applied three different probabilistic methods: frequency distributions, logistic regressions, and potential analyses to infer the resilience of larch forests relative to that of other forest *** found patters indicative of alternative stable states: bimodality in the frequency distribution of the percent of larch basal area, and the presence of an unstable state, i.e., mixed larch forests, in the potential analyses. We also found:(1) high frequency ofpurelarchforestsathighelevation,(2)the probability of pure larch forests increased mostly with elevation, and(3) pure larch forests were a stable state in the upper montane and subalpine *** study shows that the resilience of larch forests may increase with elevation, most likely due to the altitudinal effect on climate. Under the same climate conditions, land use seems to be the main factor governing the dominance of larch forests. In fact, subalpine larch forests may be more resilient, and natural succession after land abandonment, e.g., towards Pinuscembra forests, seems slower than in montane larch forests. In contrast, in the upper montane belt only intense land use regimes characterized by open canopies and forest grazing may maintain larch *** con

关键词： Resilience Ecosystem bistability Elevation Land use Natural succession Pinuscembra European larch

Hepatolithiasis:Epidemiology,presentation,classification and management of a complex disease

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World Journal of Gastroenterology 2024年第13期30卷 1836-1850页

作者： Rodrigo v.motta francesca Saffioti vasileios K Mavroeidis Translational Gastroenterology and Liver Unit Nuffield Department of MedicineUniversity of OxfordOxford OX39DUUnited Kingdom Department of Gastroenterology and Hepatology Oxford University Hospitals NHS Foundation TrustJohn Radcliffe HospitalOxford OX39DUUnited Kingdom UCL Institute for Liver and Digestive Health and Sheila Sherlock Liver Unit Royal Free Hospital and University College LondonLondon NW32QGUnited Kingdom Department of HPB Surgery Bristol Royal InfirmaryUniversity Hospitals Bristol and Weston NHS Foundation TrustBristol BS28HWUnited Kingdom Department of Transplant Surgery North Bristol NHS TrustSouthmead HospitalBristol BS105NBUnited Kingdom Department of Gastrointestinal Surgery North Bristol NHS TrustSouthmead HospitalBristol BS105NBUnited Kingdom

The term hepatolithiasis describes the presence of biliary stones within the intrahepatic bile ducts,above the hilar confluence of the hepatic *** disease is more prevalent in Asia,mainly owing to socioeconomic and dietary factors,as well as the prevalence of biliary *** the last century,owing to migration,its global incidence has *** main pathophysiological mechanisms involve cholangitis,bile infection and biliary strictures,creating a self-sustaining cycle that perpetuates the disease,frequently characterised by recurrent episodes of bacterial infection referred to as syndrome of“recurrent pyogenic cholangitis”.furthermore,long-standing hepatolithiasis is a known risk factor for development of intrahepatic *** classifications have aimed at providing useful insight of clinically relevant aspects and guidance for *** management of symptomatic patients and those with complications can be complex,and relies upon a multidisciplinary team of hepatologists,endoscopists,interventional radiologists and hepatobiliary surgeons,with the main goal being to offer relief from the clinical presentations and prevent the development of more serious *** comprehensive review provides insight on various aspects of hepatolithiasis,with a focus on epidemiology,new evidence on pathophysiology,most important clinical aspects,different classification systems and contemporary management.

关键词： Cholelithiasis Intrahepatic stones Cholangiocarcinoma Biliary parasites Recurrent pyogenic cholangitis Oriental cholangiohepatitis Hepatectomy Cholangioscopy Liver transplant Paediatric

Unwrapping reworked crust at the Columbia supercontinent margin within central southern Amazon Craton using multi-source geophysics and geochronology data synergy

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Geoscience frontiers 2022年第3期13卷 35-52页

作者： João G.motta P.G.Betts v.T.Meira v.G.Trevisan C.R.de Souza filho Institute of Geosciences University of CampinasCampinasSão PauloBrazil Camborne School of Mines University of ExeterPenryn CampusPenrynCornwallUnited Kingdom School of Earth Atmosphere and EnvironmentMonash University(Clayton Campus)ClaytonVICAustralia Anglo American Níquel Brasil Ltda. Avenida Interlândia502 QD 87LST 68 e 10GoiâniaGoiásBrazil

The geometry and evolution of pre-existing basement in accretionary belts bordering supercontinents are often *** interpretation of long-wavelength potential field satellite data can image deep crust structure,improving our understanding of lithospheric processes that formed these margins ***,we present a multidisciplinary interpretation of the lithospheric architecture of the central southern Amazon Craton,a fragment of an accretionary belt at the southwestern Columbia supercontinent ***-borne gravity and magnetic data,airborne magnetic data,passive seismic(v_(p)/v_(s) ratio,crustal thickness)and seismic tomography data reveals that basement terranes from the interior of the craton extend into the accretionary margin of *** demonstrate a vertically heterogeneous structure with an underlying strongly reworked pre-Columbia tectonic wedge that sustained prolonged modification during the supercontinent assembly as corroborated by Nd isotope and geochronology *** isotope data suggest that the protracted orogenic wedge was influenced by subduction angle shifts over time,including addition of substantial juvenile material during slab retreat *** interplay promoted Craton growth at the supercontinent margin while keeping a subtle record of the pre-existing *** findings point to the possible misrepresentation of basement extension and geometry of supercontinent margins elsewhere.

关键词： Satellite gravity Satellite magnetics Columbia Accretionary belt Amazon Craton Geochronology

Palliative long-term abdominal drains vs large volume paracenteses for the management of refractory ascites in end-stage liver disease

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World Journal of Hepatology 2024年第3期16卷 428-438页

作者： Senamjit Kaur Rodrigo v motta Bryony Chapman victoria Wharton Jane D Collier francesca Saffioti Oxford Liver Unit Department of Gastroenterology and HepatologyOxford University Hospitals NHS Foundation TrustOxford OX39DUUnited Kingdom Oxford Liver Unit and Translational Gastroenterology Unit Nuffield Department of MedicineUniversity of OxfordOxford OX39DUUnited Kingdom

BACKGROUND Long-term abdominal drains(LTAD)are a cost-effective palliative measure to manage malignant ascites in the community,but their use in patients with end-stage chronic liver disease and refractory ascites is not routine *** safety and cost-effectiveness of LTAD are currently being studied in this setting,with preliminary positive *** hypothesised that palliative LTAD are as effective and safe as repeat palliative large volume paracentesis(LvP)in patients with cirrhosis and refractory ascites and may offer advantages in patients’quality of *** To compare the effectiveness and safety of palliative LTAD and LvP in refractory ascites secondary to end-stage chronic liver *** A retrospective,observational cohort study comparing the effectiveness and safety outcomes of palliative LTAD and regular palliative LvP as a treatment for refractory ascites in consecutive patients with end-stage chronic liver disease followed-up at our United Kingdom tertiary centre between 2018 and 2022 was ***’s exact tests and the Mann-Whitney U test were used to compare qualitative and quantitative variables,***-Meier survival estimates were generated to stratify time-related outcomes according to the type of *** Thirty patients had a total of 35 indwelling abdominal drains and nineteen patients underwent regular *** baseline characteristics were similar between the *** antibiotics were more frequently prescribed in patients with LTAD(P=0.012),while the incidence of peritonitis did not differ between the two groups(P=0.46).The incidence of acute kidney injury(P=0.014)and ascites/drain-related hospital admissions(P=0.004)were significantly higher in the LvP *** overall survival was similar in the two groups(log-rank P=0.26),but the endpoint-free survival was significantly shorter in the LvP group(P=0.003,Pfor first ascites/drain-related admission,acute kidney injury and drain

关键词： Decompensated liver cirrhosis Indwelling abdominal catheter Rocket drain Palliative care Safety Quality of life

Climatic niche breadths of the Atlantic forest snakes do not increase with increasing latitude

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Current Zoology 2022年第5期68卷 535-540页

作者： José Thales da motta Portillo fausto Erritto Barbo Ricardo J.Sawaya Programa de Pós-Graduação em Biologia Animal Instituto de BiociênciasLetras e Ciências ExatasUniversidade Estadual Paulista“Júlio de Mesquita Filho”Rua Cristóvão Colombo2265São Josédo Rio PretoSão Paulo 15054-000BrazilLaboratório de Coleções ZoológicasInstituto ButantanAvenida Vital Brazil1500São Paulo 05503-900Braziland Centro de Ciências Naturais e HumanasUniversidade Federal do ABCRua Arcturus03São Bernardo do CampoSão Paulo 09606-070Brazil

The climatic niche is a central concept for understanding species distribution,with current and past climate interpreted as strong drivers of present and historical-geographical *** aim is to understand whether Atlantic forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing *** also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche *** breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species *** implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and *** also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche *** niche breadths were not related to *** niche breadths decreased with increasing latitude and presented a high phylogenetic signal,that is,significant phylogenetic niche *** rejected the tradeoff hypotheses of temperature and precipitation niche *** results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic *** then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

关键词： Atlantic forest biogeography climatic niche latitudinal gradient snakes

Influence of physical-anatomical wood variables on charcoal physical-mechanical properties

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Journal of forestry Research 2023年第2期34卷 531-538页

作者： Allan motta Couto Thiago Campos Monteiro Paulo fernando Trugilho JoséTarcísio Lima JoséReinaldo Moreira da Silva Alfredo Napoli Diego Pierre de Almeida Department of forestry Science State University of Mato Grosso do Sul–UEMSAv.Graziela Maciel BarrosoKm 12 Zona RuralAquidauanaMS 79200000Brazil Department of forestry Engineering and Technology Federal University of Paraná–UFPRA V.Pref.Lothário Meissner 632Jardim BotânicoCuritibaPR 80210170Brazil Department of forestry Science Federal UniversityLavras–UFLALavrasMG 37200000Brazil Département de Performance Des Systèmes de Production Et de Transformation Tropicaux Centre de Coopération Internationale em Recherche Agronomique pour le Développement–CIRADMontpellierFrance

This research assessed the relationship between wood physical-anatomical variables and charcoal physical-mechanical *** trees were harvested and mechanically processed into standard pieces for laboratory *** following variables were determined:wood density,fiber length and width,fiber lumen diameter and wall thickness,fiber wall fraction,and vessel *** charcoal was produced in a laboratory and gravimetric yield,relative density,and mechanical properties ***’s correlation coefficients,multivariate statistical analysis of canonical correlation,and principal component analysis were used to evaluate the relationship between wood and charcoal *** width was not significantly correlated with charcoal *** bulk density,hardness,and strength were positively correlated with wood density,fiber length,wall thickness,and wall *** properties were negatively correlated with fiber lumen diameter and vessel *** results will help identify the best wood with adequate physical-mechanical properties for industrial charcoal proces sing.

关键词： Biomass Density Energy fiber vessel