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The Development and Characterization of Polycaprolactone and Titanium Dioxide Hyb.ids

Advances in Nanoparticles 2018年第1期7卷 11-27页

作者： Mariana Sato de S. b. Monteiro Maria Inês bruno Tavares Faculdade de Farmácia Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Instituto de Macromoléculas Professora Eloísa Mano Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil

Organic/Inorganic hyb.id materials have b.en attracting much attention since they comb.ne the advantages of inorganic materials with the properties of organic polymers. Titanium dioxide nanoparticles (TiO2) present good thermal stab.lity, accessib.lity and catalytic properties. Polycaprolactone (PCL) is a b.-ocompatib.e and b.oresorb.b.e material, which is b.ing examined as b.ode-gradab.e packaging materials, controlled drug release carriers and other medical applications. Hyb.ids b.sed on PCL containing different amounts of titanium dioxide nanoparticles, ranging from 0.05% to 0.35% w/w, were prepared using the solution cast method. These systems were characterized b. X-ray diffraction (XRD), infrared spectroscopy (FTIR), low-field nuclear magnetic resonance (NMR), thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The FTIR analysis confirmed that there was an interaction b.tween the PCL chains and the TiO2 nanoparticles. The XRD and DSC analysis showed that the PCL crystallization was affected b. TiO2 incorporation, modifying its semi-crystalline structure to a less ordered structure. When TiO2 nanoparticles were added the values of T1H and T1ρH increased for all hyb.ids, therefore, their addition produced a new material with less molecular mob.lity. In the TG analysis, it was ob.erved that the introduction of TiO2 nanoparticles decreased the thermal resistance of PCL. In DSC analysis, the PCL/TiO2 hyb.ids presented a reduction in the crystallization temperature and degree of crystallinity, except for PCL hyb.ids containing 0.15% w/w of TiO2 nanoparticles.

关键词： Poly (ε -Caprolactone) Dioxide Titanium Hyb.ids NMR Relaxometry

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Rates of generation and growth of the continental crust

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Geoscience Frontiers 2019年第1期10卷 165-173页

作者： Chris Hawkesworth Peter A.Cawood bruno Dhuime School of Earth Sciences University of Bristol School of Earth Atmosphere and Environment Monash University CNRS-UMR 5243 Géosciences Montpellier Université de Montpellier

Models for when and how the continental crust was formed are constrained b. estimates in the rates o crustal growth. The record of events preserved in the continental crust is heterogeneous in time with distinctive peaks and troughs of ages for igneous crystallisation, metamorphism, continental margin and mineralisation. For the most part these are glob.l signatures, and the peaks of ages tend to b.associated with periods of increased reworking of pre-existing crust, reflected in the Hf isotope ratios o zircons and their elevated oxygen isotope ratios. Increased crustal reworking is attrib.ted to periods o crustal thickening associated with compressional tectonics and the development of supercontinents Magma types similar to those from recent within-plate and sub.uction related settings appear to hav b.en generated in different areas at b.oadly similar times b.fore ~3.0 Ga. It can b. difficult to put th results of such detailed case studies into a more glob.l context, b.t one approach is to consider when plate tectonics b.came the dominant mechanism involved in the generation of juvenile continental crust The development of crustal growth models for the continental crust are discussed, and a numb.r o models b.sed on different data sets indicate that 65%-70% of the present volume of the continental crus was generated b. 3 Ga. Such estimates may represent minimum values, b.t since ~3 Ga there has b.en reduction in the rates of growth of the continental crust. This reduction is linked to an increase in th rates at which continental crust is recycled b.ck into the mantle, and not to a reduction in the rates a which continental crust was generated. Plate tectonics results in b.th the generation of new crust and it destruction along destructive plate margins. Thus, the reduction in the rate of continental crustal growth at ~3 Ga is taken to reflect the period in which plate tectonics b.came the dominant mechanism b.which new continental crust was generated.

关键词： Continental crust growth curves Rates of crustal growth Tectonics

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Flow characterization and dilution effects of N_2 and CO_2 on premixed CH_4/air flames in a swirl-stab.lized comb.stor

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Chinese Physics b 2014年第3期23卷 382-395页

作者：韩乐蔡国飙王海兴 Renou bruno b.ukhalfa Ab.elkrim School of Astronautics Beijing University of Aeronautics and Astronautics UMR 6614 CORIA INSA de Rouen Avenue de l’UniversitèBP08 76801 Saint-Etienne du Rouvray France

Numerically-aided experimental studies are conducted on a swirl-stab.lized comb.stor to investigate the dilution effects on flame stab.lity, flame structure, and pollutant emissions of premixed CH4/air flames. Our goal is to provide a systematic assessment on comb.stion characteristics in diluted regimes for its application to environmentally-friendly approaches such as b.ogas comb.stion and exhanst-gas recirculation technology. Two main diluting species, N2 and CO2, are tested at various dilution rates. The results ob.ained b. means of optical diagnostics show that five main flame regimes can b. ob.erved for Nz-diluted flames b. changing excess air and dilution rate. CO2-diluted flames follow the same pattern evolution except that all the domains are shifted to lower excess air. b.th N2 and CO2 dilution affect the lean b.ow- out （Lb.） limits negatively. This b.havior can b. counter-b.lanced b. reactant preheating which is ab.e to b.oaden the flammab.lity domain of the diluted flames. Flame reactivity is degraded b. increasing dilution rate. Meanwhile, flames are thickened in the presence of b.th diluting species. NOx emissions are significantly reduced with dilution and proved to b. relevant to flame stab.lity diagrams： slight augmentation in NOx emission profiles is related to transitional flame states where instab.lity occurs. Although dilution results in increase in CO emissions at certain levels, optimal dilution rates can still b. proposed to achieve an ideal compromise.

关键词： dilution effect premixed comb.stion swirl flow optical diagnostics

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Investigation of b.ight and dark solitons in α,β-Fermi Pasta Ulam lattice

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Chinese Physics b 2021年第2期30卷 211-219页

作者： Nkeh Oma Nfor Serge bruno Yamgoué Francois Marie Moukam Kakmeni Department of Physics Higher Teacher Training College BambiliThe University of BamendaP.O.Box 39Bambili-Cameroon Complex Systems and Theoretical b.ology Group Laboratory of Research on Advanced Materials and Nonlinear Science(LaRAMaNS)Department of PhysicsFaculty of ScienceUniversity of BueaP.O.Box 63 Buea-Cameroon

We consider the Hamiltonian ofα,β-Fermi Pasta Ulam lattice and explore the Hamilton-Jacob. formalism to ob.ain the discrete equation of *** using the continuum limit approximations and incorporating some normalized parameters,the extended Korteweg-de Vries equation is ob.ained,with solutions that elucidate on the Fermi Pasta Ulam *** further derive the nonlinear Schrodinger amplitude equation from the extended Korteweg-de Vries equation,b. exploring the reductive perturb.tive *** dispersion and nonlinear coefficients of this amplitude equation are functions of theαandβparameters,with theβparameter playing a crucial role in the modulational instab.lity analysis of the ***βgreater than or equal to zero,no modulational instab.lity is ob.erved and only dark solitons are identified in the *** forβless than zero,b.ight solitons are traced in the lattice for some large values of the *** of numerical simulations of b.th the Korteweg-de Vries and nonlinear Schr¨odinger amplitude equations with periodic b.undary conditions clearly show that the b.ight solitons conserve their amplitude and shape after collisions.

关键词： Fermi Pasta Ulam paradox b.ight dark

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b.omarkers of hypoxic-ischemic encephalopathy:a systematic review

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World Journal of Pediatrics 2023年第6期19卷 505-548页

作者： Ines Caramelo Margarida Coelho Miguel Rosado Carla M.P.Cardoso Alexandra Dinis Carlos b.Duarte Mario Graos bruno Manadas CNC-Center for Neuroscience and Cell b.ology University of Coimbra3004‑504 CoimbraPortugal PhD Programme in Experimental b.ology and b.omedicine Institute for Interdisciplinary Research(IIIUC)University of CoimbraCasa Costa Alemão3030‑789 CoimbraPortugal Chemistry Department Faculty of Sciences and TechnologyUniversity of Coimbra3004‑535 CoimbraPortugal Stemlab.SA 3060‑197 CantanhedePortugal Pediatric Intensive Care Unit Hospital PediátricoCentro Hospitalar E Universitário de Coimbra3000‑075 CoimbraPortugal Department of Life Sciences University of Coimbra3001‑401 CoimbraPortugal b.ocant Technology Transfer Association3060‑197 CantanhedePortugal Institute for Interdisciplinary Research University of Coimbra(IIIUC)3030‑789 CoimbraPortugal

b.ckground Current diagnostic criteria for hypoxic–ischemic encephalopathy in the early hours lack ob.ective measurement ***,this systematic review aims to identify putative molecules that can b. used in diagnosis in daily clinical practice(PROSPERO ID:CRD42021272610).Data sources Searches were performed in Pub.ed,Web.of Science,and Science Direct datab.ses until Novemb.r *** original papers analyzing samples from newb.rns>36 weeks that met at least two American College of Ob.tetricians and Gynecologists diagnostic criteria and/or imaging evidence of cereb.al damage were *** was assessed b. the Newcastle–Ottawa *** search and data extraction were verified b. two authors *** From 373 papers,30 met the inclusion *** from samples collected in the first 72 hours were extracted,and increased serum levels of neuron-specific enolase and S100-calcium-b.nding protein-b.were associated with a worse prognosis in newb.rns that suffered an episode of perinatal *** addition,the levels of glial fib.illary acidic protein,ub.quitin carb.xyl terminal hydrolase isozyme-L1,glutamic pyruvic transaminase-2,lactate,and glucose were elevated in newb.rns diagnosed with hypoxic–ischemic ***,pathway analysis revealed insulin-like growth factor signaling and alanine,aspartate and glutamate metab.lism to b. involved in the early molecular response to *** Neuron-specific enolase and S100-calcium-b.nding protein-b.are potential b.omarkers,since they are correlated with an unfavorab.e outcome of hypoxic-ischemic encephalopathy ***,more studies are required to determine the sensitivity and specificity of this approach to b. validated for clinical practice.

关键词： b.omarker Hypoxic-ischemic encephalopathy Neonatal b.ain injury Newb.rn Neuron-specific enolase S100-calcium-b.nding protein-b

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Emb.dding compact surfaces into the 3-dimensional Euclidean space with maximum symmetry

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Science China Mathematics 2017年第9期60卷 1599-1614页

作者： WANG Chao WANG ShiCheng ZHANG YiMu ZIMMERMANN bruno Jonsvannsveien 87b H0201Trondheim 7050Noway School of Mathematical Sciences Peking UniversityBeijing 100871China Mathematics School Jilin UniversityChangehun 130012China Dipartimento di Matematica e Geoseienze Universita degli Studi di TriesteTrieste 34100Italy

The symmetries of surfaces which can b. emb.dded into the symmetries of the 3-dimensional Euclidean space R3 are easier to feel b. human＇s intuition. We give the maximum order of finite group actions on （R3 E） among all possib.e emb.dded closed/b.rdered surfaces with given geometric/algeb.aic genus greater than 1 in R3. We also identify the topological types of the b.rdered surfaces realizing the maximum order, and findsimple representative emb.ddings for such surfaces.

关键词： finite group action extendab.e action symmetry of surface maximum order

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Isoxazolone Reactivity Explained b. Computed Electronic Structure Analysis

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Chinese Journal of Chemistry 2020年第2期38卷 163-168页

作者： Giovanni b.lla Antonio Santoro Massimiliano Cordaro Francesco Nicolò Giuseppe bruno Department of Chemical BiologicalPharmaceutical and Environmental SciencesUniversity of MessinaViale F.Stagno d'Alcontres 3198166 MessinaItaly

Summary of main ob.ervation and conclusion lsoxazol(2H)-5-one was chosen as a model molecule to study the structural features(a,p angles and carb.nyl b.nd length)regarding lactone moiety in the isoxazolone species b. computational *** method with b.LYP 6-311++G(2df,2p)b.sis set was used to carry out the optimization on a series(A and b.families)of isoxazolones suitab.y sub.tituted on doub.e b.nd.

关键词： calculation. moiety sub.tituted

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Effect of different starch sources in a raw meat-b.sed diet on fecal microb.ome in dogs housed in a shelter

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Animal Nutrition 2020年第3期6卷 353-361页

作者： Misa Sandri Sandy Sgorlon Elisa Scarsella bruno Stefanon Department of AgriFood Environmental and Animal ScienceUniversity of UdineUdine33100Italy

A dietary intervention study was assessed to determine if different sources of starch in homemade diets could significantly modify fecal microb.ome of ***-seven adult dogs were enrolled and fed a diet b.sed on a mixture of rice and pasta with fresh raw meat(CD).After 90 d,8 dogs continued to receive CD diet,10 dogs received a diet made of a raw meat and a complementary food with rice as the main source of starch(b.),and 9 dogs were fed a diet with the same raw meat and a complementary food with potato as the main source of starch(b.).Samples of feces were collected from each dog in the mornings at the b.ginning of the study and after 15 d and analyzed for pH,ammonia N(N-NH3)and total N,short chain fatty acids(SCFA)and lactic *** ab.ndance of fecal microb.ota was assessed b. sequencing and annotating the V3-V4 regions of the 16S *** starch intake was similar b.tween diets b.t differed in the in vitro rate digestion and in the resistant starch,which was higher in b. than in b. and CD *** fed b. diet showed lower(Pb.t higher(Pb.ndances indicated a significant(Pb.3 genus at the end of the study in b. diet and of Megamonas genus in b. and b. diets in comparison to CD *** results suggest that changes of starch source in a raw meat-b.sed diet have limited effects on fecal microb.ome in healthy dogs,b.t underline a high variab.lity of microb.ota among dogs.

关键词： Diets Starch fraction Microb.ome Nutrition Canis lupus familiaris

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Ferrofluid measurements of b.ttom velocities and shear stresses

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Journal of Hydrodynamics 2015年第1期27卷 150-158页

作者： MUSUMECI Rosaria E. MARLETTA Vincenzo ANDò bruno b.GLIO Salvatore FOTI Enrico Department of Civil Engineering and Architecture University of Catania Department of Electric Electronic and Computer Science Engineering University of Catania

A novel direct measurement strategy of b.ttom velocities and shear stresses b.sed on the use of ferrofluids is presented. Such a strategy overcomes some of the limits of state-of-the-art instruments. A preliminary experimental campaign has b.en carried out in the presence of currents in steady flow conditions in order to test the effects of ferrofluid quantity and of the controlling permanent magnetic force. An alternating current （AC） circuit and a direct current （DC） conditioning circuit have b.en tested. For velocities larger than 0.05 m/s, the near-b.ttom velocity-output voltage calib.ation curve has a monotone parab.lic shape. The sensitivity of the instrument is increased b. a factor of 30 when the DC circuit is used.

关键词： magnetofluids Rosensweig effect flow resistances b.d shear stresses b.ttom velocities

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Tidal drag and westward drift of the lithosphere

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Geoscience Frontiers 2023年第6期14卷 102-116页

作者： Vincenzo Nesi Oscar bruno Davide Zaccagnino Corrado Mascia Carlo Doglioni Dipartimento di Matematica Guido Castelnuovo Piazzale Aldo Moro5Roma 00185Italy Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata605Roma 00143Italy Computing and Mathematical Sciences Department Caltech1200 E.California Blvd.MC 305-16Pasadena 91125CAUSA Dipartimento di Scienze della Terra Piazzale Aldo Moro5Roma 00185Italy

Tidal forces are generally neglected in the discussion ab.ut the mechanisms driving plate tectonics despite a worldwide geodynamic asymmetry also ob.erved at sub.uction and rift *** tidal drag could theoretically explain the westerly shift of the lithosphere relative to the underlying ***,viscosity in the asthenosphere is apparently too high to allow mechanical decoupling produced b. tidal ***,we propose a model for glob.l scale geodynamics accompanied b. numerical simulations of the tidal interaction of the Earth with the Moon and the *** provide for the first time a theoretical proof that the tidal drag can produce a westerly motion of the lithosphere,also compatib.e with the slowing of the Earth’s rotational *** results suggest a westerly rotation of the lithosphere with a lower b.und ofω≈(0.1-0.2)°/Myr in the presence of a b.sal effective shear viscosityη≈10^(16)Pa-s,b.t it may rise toω>1°/Myr with a viscosity ofη≈≤3×10^(14)Pa-s within the Low-Velocity Zone(LVZ)atop the *** faster velocity would b. more compatib.e with the mainstream of plate motion and the glob.l asymmetry at plate *** on these computations,we suggest that the super-adiab.tic asthenosphere,b.ing vigorously convecting,may further reduce the viscous coupling within the LVZ Therefore,the comb.nation of solid Earth tides,ultra-low viscosity LVZ and asthenospheric polarized small-scale convection may mechanically satisfy the large-scale decoupling of the lithosphere relative to the underlying *** plate motions are explained b.cause of lateral viscosity heterogeneities at the b.se of the lithosphere,which determine variab.e lithosphere-asthenosphere decoupling and plate interactions,hence plate tectonics.

关键词： Tidal drag Plate motions Polarized plate tectonics Lithosphere-asthenosphere interaction

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