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Gravity-Driven Listric Growth f.ult and Sedimentation in the Lagoa do Peixe, Rio Grande do Sul coastal Plain, Brazil

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Open Journal of.Geology 2024年第4期14卷 594-616页

作者： Bruno Silva da f.ntoura Adelir José Strieder Iran carlos Stalliviere corrêa paulo Rogério Mendes Instituto de Geociê ncias UFRGS Porto Alegre Brazil Engenharia Geoló gica Centro de Engenharias UFPel Pelotas Brasil HIDROSERV— Servi&#231os Geol&#243gicos e Geof&#237sicos Ltda. Porto Alegre Brazil

High f.equency, high resolution GPR surveys are successf.lly applied to investigate near-surf.ce stratif.cation architecture of.sedimentary units in coastal plains and to def.ne their depositional conditions. However, low f.equency GPR surveys to investigate f.ult-related depositional systems at greater depths are scarce. This survey was designed investigate a > 100 km long linear escarpment that controls the northwest margin of.the Lagoa do Peixe, an important lagoon in Rio Grande do Sul coastal Plain (RGScP, Brazil). The traditional approach points that RGScP was developed by juxtaposition of.f.ur lagoons/barrier systems as consequence of.sea level changes;no def.rmational structure is admitted to exist bef.re. The low f.equency GPR (50 MHz, RTA antenna) and geological surveys carried out in the RGScP showed the existence of.a large, gravity-driven listric growth f.ult controlling the Lagoa do Peixe escarpment and hangingwall sedimentation. The radargrams in f.ur subareas along the Lagoa do Peixe Growth f.ult could be interpreted f.llowing the seismic expression of.rif.-related depositional systems. The radargrams enabled to distinguish three main lagoonal deposition radarf.cies. The lower lagoonal radarf.cies is a convex upward unit, thicker close to growth f.ult;the radarf.cies geometry indicates that f.ult displacement rate surpasses the sedimentation rate, and its upper stratum is aged ~3500 l4c years BP. The second lagoonal radarf.cies is a triangular wedge restricted to the lagoon depocenter, whose geometry indicates that f.ult displacement and the sedimentation rates kept pace. The upper lagoonal radarf.cies is being deposited since 1060 ± 70 l4c years BP, under sedimentation rate higher than f.ult displacement rate. The results indicate that low f.equency GPR surveys can help in investigating f.ult-related depositional systems in coastal zones. They also point to a new approach in dealing with RGScP stratigraphy.

关键词： GPR (Ground-Penetrating Radar) Growth f.ult Sedimentation Radarf.cies coastal Plain

A RANS-Vof.Numerical Model to Analyze the Output Power of.An OWc-WEc Equipped with Wells and Impulse Turbines in A Hypothetical Sea-State

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china Ocean Engineering 2020年第6期34卷 760-771页

作者： paulo R.f.Teixeira Raf.el A.A.c.Gonçalves Eric Didier Engineering School Universidade Federal do Rio Grande-FURGRio GrandeRS 96203-900Brazil Harbours and Maritime Structures Division Hydraulics and Environment DepartmentLaboratório Nacional de Engenharia Civil-LNECLisbon 1700-066Portugal

Wave energy is a renewable source with signif.cant amount in relation to the global demand. A good concept of.a device applied to extract this type of.energy is the onshore oscillating water column wave energy converter(OWc-WEc). This study shows a numerical analysis of.the diameter determination of.two types of.turbines, Wells and Impulse, installed in an onshore OWc device subjected to a hypothetical sea state. commercial sof.ware f.UENT?,which is based on RANS-Vof.Reynolds-Averaged Navier-Stokes equations and Volume of.f.uid technique), is employed. A methodology that imposes air pressure on the chamber, considering the air compressibility ef.ect, is used. The mathematical domain consists of.a 10 m deep f.ume with a 10 m long and 10 m wide OWc chamber at its end(geometry is similar to that of.the Pico's plant installed in Azores islands, Portugal). On the top of.the chamber, a turbine works with air exhalation and inhalation induced by the water f.ee surf.ce which oscillates due to the incident wave. The hypothetical sea state, represented by a group of.regular waves with periods f.om 6 to 12 s and heights f.om 1.00 to 2.00 m(each wave with an occurrence f.equency), is considered to show the potential of.the presented methodology. Maximum ef.iciency(relation between the average output and incident wave powers) of.6% was obtained by using a Wells turbine with the diameter of.2.25 m, whereas the ef.iciency was 44% by an Impulse turbine with the diameter of.1.70 m.

关键词： wave energy oscillating water column Wells turbine Impulse turbine RANS-Vof compressible air

The dynamics of.a symmetric coupling of.three modif.ed quadratic maps

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chinese Physics B 2013年第8期22卷 233-237页

作者： paulo c. Rech Departamento de f.sica Universidade do Estado de Santa Catarina89219-710 Joinville Brazil

We investigate the dynamical behavior of.a symmetric linear coupling of.three quadratic maps with exponential terms, and identif. various interesting f.atures as a f.nction of.two control parameters. In particular, we investigate the emergence of.quasiperiodic states arising f.om Naimark-Sacker bif.rcations of.stable period-l, period-2, and period-3 orbits. We also investigate the multistability in the same coupling. Lyapunov exponents, parameter planes, phase space portraits, and bif.rcation diagrams are used to investigate transitions f.om periodic to quasiperiodic states, f.om quasiperiodic to mode-locked states and to chaotic states, and f.om chaotic to hyperchaotic states.

关键词： Naimark-Sacker bif.rcation quasiperiodicity chaos hyperchaos

Dynamics in the Parameter Space of.a Neuron Model

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chinese Physics Letters 2012年第6期29卷 64-67页

作者： paulo c.Rech Departamento de f.sica Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

Some two-dimensional parameter-space diagrams are numerically obtained by considering the largest Lyapunov exponent f.r a f.ur-dimensional thirteen-parameter Hindmarsh-Rose neuron *** dif.erent parameter planes are considered,and it is shown that depending on the combination of.parameters,a typical scenario can be preserved:f.r some choice of.two parameters,the parameter plane presents a comb-shaped chaotic region embedded in a large periodic *** is also shown that there exist regions close to these comb-shaped chaotic regions,separated by the comb teeth,organizing themselves in period-adding bif.rcation cascades.

关键词： parameter chaotic shaped

Ef.ect of.radiative loss mechanisms on f.R thermometric parameters of.Nd^(3+)-doped lithium tellurite glasses

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Journal of.Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optical and Photothermal Spectroscopy Group(GEOf. Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Inf.rmation Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of.Physics of.São carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials f.r thermometers based on the f.uorescence intensity ratio(f.R)***,at high Nd^(3+)concentrations,energy transf.r(ET)processes such as optical reabsorption and cross-relaxation can af.ect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of.Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in f.uorescence thermometers,in the temperature range f.om 299 to 371 *** results indicate a strong dependence of.the f.R parameters on the Nd^(3+)concentration,due to changes in the emission band prof.les caused by optical reabsorption of.the Nd^(3+)emissions and cross-relaxation processes.A decrease of.the relative sensitivity of.the ratio^(4)f.(5/2)→^(4)I_(9/2)/^(4)f.(3/2)→^(4)I_(9/2)is observed f.r samples doped with higher amounts of.Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass f.uorescence intensity ratio Optical thermometry Judd-Of.lt Rare earths

Repeat hepatectomy f.r recurrent colorectal liver metastases:A comparative analysis of.short-and long-term results

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Hepatobiliary & Pancreatic Diseases International 2022年第2期21卷 162-167页

作者： paulo f.gueiredo costa f.bricio f.rreira coelho Vagner Birk Jeismann Jaime Arthur Pirola Kruger Gilton marques f.nseca Ivan cecconello paulo Herman Digestive Surgery Brazilian college of.Digestive Surgery(colégio Brasileiro de cirurgia Digestiva-cBcD) São PauloBrazil Digestive Surgery Division Department of GastroenterologyUniversity of São Paulo School of MedicineSão PauloBrazil Instituto do câncer do Estado de São paulo(IcESP) São PauloBrazil

Background: Liver recurrence af.er resection of.colorectal liver metastases(cRLM) is f.equent. Repeat hepatectomy has been shown to have satisf.ctory perioperative results. However, the long-term outcomes and the benef.s f.r patients with early recurrence have not been clarif.d. The aim of.this study was to compare the short-and long-term outcomes of.patients undergoing single hepatectomy and repeat hepatectomy f.r cRLM. Additionally, the oncological outcomes of.patients with early( ≤ 6 months) and late recurrence who underwent repeat hepatectomy were compared. Methods: consecutive adult patients undergoing hepatectomy f.r cRLM between June 20 0 0 and f.bruary 2020 were included and divided into two groups: single hepatectomy and repeat hepatectomy. Results: A total of.709 patients were included: 649 in the single hepatectomy group and 60 in the repeat hepatectomy group. Patients in the repeat hepatectomy group underwent more cycles of.preoperative chemotherapy [4(3-6) vs. 3(2-4), P = 0.003]. Patients in the single hepatectomy group more f.equently underwent major hepatectomies(34.5% vs. 16.7%, P = 0.004) and had a greater number of.lesions resected(2.9 ± 3.6 vs. 1.9 ± 1.8, P = 0.011). There was no increase in operative time, estimated blood loss, length of.hospital stay, complications, or mortality in the repeat hepatectomy group. There were no dif.erences in overall survival( P = 0.626) and disease-f.ee survival( P = 0.579) between the two groups. Similarly, f.r patients underwent repeat hepatectomy, no dif.erence was observed between the early and late recurrence groups in terms of.overall survival( P = 0.771) or disease-f.ee survival( P = 0.350). conclusions: Repeat hepatectomy is f.asible and saf., with similar short-and long-term outcomes when compared to single hepatectomy. Surgical treatment of.early liver recurrence of.ers similar oncological outcomes to those obtained f.r late recurrence.

关键词： colorectal cancer Metastasis Hepatectomy Postoperative complications Survival analysis

Development and characterization of.3caO·P_(2)O_(5)-SiO_(2)-MgO glass-ceramics with dif.erent crystallization degree

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Journal of.Advanced ceramics 2013年第4期2卷 378-388页

作者： Juliana Kelmy M.f.DAGUANO paulo A.SUZUKI Kurt STREcKER JoséMartinho marques de OLIVEIRA Maria Helena f.gueira Vaz f.RNANDES claudinei SANTOS Universidade de São paulo-Escola de Engenharia de Lorena USP-EEL-Pólo Urbo-Industrials/nGleba AI-6Lorena-SPCEP 12600-000Brazil Universidade f.deral de São João del-Rei -UFSJ-CENENCampus S^(to)Antônio-Praça Frei Orlando 170-CentroS.J.del-Rei-MG.CEP 36307-352Brazil Escola Superior Aveiro Norte Edifício Rainha3720-232 O.AzeméisPortugal Universidade de Aveiro Campus Universitário de Santiago 3810-193 AveiroPortugal Universidade do Estado do Rio de Janeiro-f.culdade de Tecnologia de Resende-UERJ-f.T-Rod.Presidente Dutra km298Resende-RJCEP 27537-000Brazil

The caO-P_(2)O_(5)-SiO_(2)-MgO system presents several compounds used as biomaterials such as hydroxyapatite(HA),tricalcium phosphate(TcP)and TcP with magnesium substituting partial calcium(TcMP).Theβ-TcMP phase with whitlockite structure has interesting biological f.atures and mechanical properties,meeting the requirements of.a bioactive material f.r bone *** this work,the production of.Mg-doped TcP,β-TcMP,has been investigated by crystallization f.om a glass composed of.52.75 wt%3caO·P_(2)O_(5),30 wt%SiO_(2)and 17.25 wt%MgO(i.e.,31.7 mol%caO,10.6 mol%P_(2)O_(5),26.6 mol%MgO and 31.1 mol%SiO_(2))using heat treatments between 775℃and 1100℃f.r up to 8 *** devitrif.cation process of.the glass has been accompanied by dif.erential scanning calorimetry(DSc),high-resolution X-ray dif.raction(HRXRD),relative density and bending strength *** characterization by HRXRD and DSc revealed the occurrence of.whitlockite soon af.er the bulk glass preparation,a transient non-cataloged silicate between 800℃and 1100℃,and the f.rmation of.diopside in samples treated at 1100℃as crystalline *** overall crystalline f.action varied f.om 26%to 70%depending on the heat ***,contraction of.the a-axis lattice parameter and expansion of.the c-axis lattice parameter of.the whitlockite structure have been observed during the heat treatments,which were attributed to theβ-TcMP f.rmation with the partial substitution of.ca^(2+)by Mg^(2+).Relative densities near 99%and 97%f.r the glass and glass-ceramics respectively indicated a discrete reduction as a f.nction of.the devitrif.cation *** strengths of.70 MPa and 120 MPa were determined f.r the glass and glass-ceramic material crystallized at 975℃f.r 4 h,respectively.

关键词： glass-ceramics heat treatment high-resolution X-ray dif.raction(HRXRD) bending strength

Ef.ect of.ce-base mischmetal addition on the microstructure and mechanical properties of.hot-rolled ZK60 alloy

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Journal of.Magnesium and Alloys 2021年第3期9卷 995-1006页

作者： E.P.Silva R.H.Buzolin f.marques f.Soldera U.Alf.ro H.c.Pinto Institute of.Engineering Science and Technology(IECT)Federal University of Vales do Jequitinhonha e Mucuri(UFVJM)JanaúbaMGBrazil São carlos School of.Engineering(EESc) University of São Paulo(USP)Department of Materials EngineeringCEP 13563-120 São Carlos-SPBrazil christian Doppler Laboratory f.r Design of.high-perf.rmance alloys by thermomechanical processing Kopernikusgasse 24/I8010 GrazAustria Technische Universität Graz(TU Graz) Institute of Materials ScienceJoining and FormingKopernikusgasse 24/I8010 GrazAustria Institute of.f.nctional Materials Department of Materials Science and EngineeringSaarland UniversitySaarbrueckenGermany German Aerospace center(DLR)Institute of.Materials Research Linder Höhe51147 CologneGermany

Mg-Zn-Zr(ZK)alloys exhibit notably high mechanical strength amongst all magnesium alloy ***,due to the f.rmation of.low melting point Mg_3Zn_7-precipitates,these alloys are susceptible to hot cracking,thus compromising their metallurgical *** addition of.rare earths to ZK alloys is an alternative to f.rm higher melting point intermetallic compounds,speed up dynamic recrystallization,ref.ne grain size,enhance corrosion resistance and extend the service temperature due to improved creep *** work deals with the ef.ect of.ce-base mischmetal addition on the hot rolling behaviour of.as-cast ZK60 *** microstructure investigation conducted using electron microscopy and X-Ray dif.raction shows that precipitation of.Mg_(7)Zn_(3) intermetallics occur during hot rolling,whereas no f.rther precipitation is observed f.r the ZK60-Mm *** f.agmentation of.the intermetallic compounds occur during hot rolling and f.ner particles of.Mg_(7)Zn_(3) are observed f.r the ZK60,whereas Mg_(7)Zn_(3) and Mg Zn_(2) ce intermetallics are f.rmed in the alloy modif.ed with mischmetal addition.A higher f.action of.dynamically recrystallized grains is observed f.r the ZK60-Mm in comparison to the *** recrystallization takes place in ZK60 with the f.rmation of.sub-grains near to the intermetallics and the addition of.mischmetal promotes the occurrence of.discontinuous recrystallization with the nucleation of.new grains close to the *** mechanical strength and,in particular,the ductility of.the hot-rolled alloys are notably improved when compared to the same alloys in the as-cast *** mechanical strength is,however,higher f.r the ZK60 *** solid solution strengthening,sof.er Mg Zn_(2) ce intermetallics and more extensive recrystallization contribute to reduce the mechanical strength of.*** in both alloys are initiated at coarse intermetallics and propagate through intermetallic-rich regions.

关键词： Magnesium alloys Hot rolling Mischmetal Recrystallization Microstructure Mechanical properties

changes in the Dynamics of.a Rössler Oscillator by an External f.rcing

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chinese Physics Letters 2013年第3期30卷 22-25页

作者： Amanda c.Mathias paulo c.Rech Departamento de f.sica Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

We report some results indicating changes in the observed dynamics of.the Rössler model under the inf.uence of.external sinusoidal *** varying the control parameters of.the external sinusoidal f.rcing,namely the amplitude and the angular f.equency,we show,through numerical simulations which include parameter planes and Lyapunov exponents,that the external f.rcing can produce both chaos-order and order-chaos *** also show that the sinusoidal f.rcing may generate hyperchaos.

关键词： chaos sinusoidal transitions