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The Effectiveness of the Havriliak-Negami Model in predicting the Master Curves of the Asphalt Blends with SBS Triblock Copolymer and Organic-Montmorillonite at Different Temperatures and Frequencies

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Journal of Materials Science and Chemical Engineering 2024年第7期12卷 23-39页

作者： María Ángeles vargas-Hernández Miguel Ángel vargas pedro R. García-morán Humberto vázquez-Torres Divisin de Ingeniera Qumica y Bioqumica TecNMTecnolgico de Estudios Superiores de Ecatepec Edo. de Mxico Mxico Facultad de Qumica Universidad Nacional Autonma de Mxico Cd. de Mxico Mxico Facultad de Ciencias Bsicas Ingeniera y Tecnologa Universidad Autnoma de Tlaxcala Tlaxcala Mxico Departamento de Fsica Universidad Autnoma Metropolitana-Iztapalapa Cd. de Mxico Mxico

The dynamic viscoelastic properties of asphalt AC-20 and its composites with Organic-Montmorillonite clay (OMMt) and SBS were modeled using the empirical Havriliak-Negami (HN) model, based on linear viscoelastic theory (LvE). The HN parameters, α, β, G0, G∞and τHN were determined by solving the HN equation across various temperatures and frequencies. The HN model successfully predicted the rheological behavior of the asphalt and its blends within the temperature range of 25˚C - 40˚C. However, deviations occurred between 40˚C - 75˚C, where the glass transition temperature Tg of the asphalt components and the SBS polymer are located, rendering the HN model ineffective for predicting the dynamic viscoelastic properties of composites containing OMMt under these conditions. Yet, the prediction error of the HN model dropped to 2.28% - 2.81% for asphalt and its mixtures at 100˚C, a temperature exceeding the Tg values of both polymer and asphalt, where the mixtures exhibited a liquid-like behavior. The exponent α and the relaxation time increased with temperature across all systems. Incorporating OMMt clay into the asphalt blends significantly enhanced the relaxation dynamics of the resulting composites.

关键词： Asphalt Blends Master Curve Linear viscoelasticity Havriliak-Negami Model

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Failure to Rescue as a Quality Metric in Congenital Heart Surgeries in a High-Complexity Service provider Institution Located in a Middle-Income Country

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Congenital Heart Disease 2024年第2期19卷 207-218页

作者： Gustavo Cruz Santiago pedroza Juan F.vélez Jessica Largo Juan F.Tejada Jorge H.Mejía-Mantilla Departamento de Anestesiología Fundación Valle del LiliCali760032Colombia Centro de Investigaciones Clínicas Fundación Valle del LiliCali760032Colombia Departamento de Cardiología pediátrica Fundación Valle del LiliCali760032Colombia Facultad de Medicina Universidad IcesiCali760031Colombia Unidad de Cuidado Intensivo Fundación Valle del LiliCali760032Colombia

Background:Failure to rescue has been an effective quality metric in congenital heart ***,mor-bidity and mortality depend greatly on non-modifiable individual factors and have a weak correlation with better-quality *** aim to measure the complications,mortality,and risk factors in pediatric patients undergoing congenital heart surgery in a high-complexity institution located in a middle-income country and compare it with other institutions that have conducted a similar ***:A retrospective observational study was conducted in a high-complexity service provider institution,in Cali,*** pediatric patients undergoing any congenital heart surgery between 2019 and 2022 were *** main outcomes evaluated in the study were complication,mortality,and failure to rescue *** and multivariate logistic regression analysis was performed with mortality as the outcome ***:We evaluated 308 congenital heart *** the outcomes,201(65%)complications occurred,23(7.5%)patients died,and the FTR of the entire cohort was 11.4%.The presence of a postoperative complication(OR 14.88,CI 3.06–268.37,p=0.009),age(OR 0.79,CI 0.57–0.96,p=0.068),and urgent/emergent surgery(OR 8.14,CI 2.97–28.66,pvariables in predicting ***:Failure to rescue is an effective and comparable quality measure in healthcare institutions and is the major contributor to postoperative mortality in congenital heart *** our higher mortality and complication rate,we obtained a comparable failure to rescue rate to high-income countries’health institutions.

关键词： Congenital heart surgery complication mortality failure to rescue quality metric

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preliminary analysis on roles of metal–organic compounds in the formation of invisible gold

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Acta Geochimica 2021年第6期40卷 1050-1072页

作者： Medet Junussov Mádai Ferenc Kristály Ferenc Tòth Tivadar Fintor Krisztián Muránszky Gábor prekob Ádám Hámor-vidóMária Department of Mineralogy and petrography Institute of Mineralogy and GeologyFaculty of Earth Sciences and EngineeringUniversity of MiskolcMiskolc-Egyetemváros 3515Hungary Institute of Mineralogy and Geology Faculty of Earth Sciences and EngineeringUniversity of MiskolcMiskolc-Egyetemváros 3515Hungary Department of Mineralogy and Geochemistry Faculty of Science and InformaticsUniversity of SzegedAradi vértank tere 1Szeged 6720Hungary Institute of Chemistry Faculty of Material Sciences and EngineeringUniversity of MiskolcMiskolc-Egyetemváros 3515Hungary Department of Geology and Meteorology Institute of Geography and Earth SciencesFaculty of SciencesUniversity of PécsVasvári pál utcaPecs 7622Hungary

The paper comprises new analytical data on the nature and occurrence of gold in solid pyrobitumen,closely associated with the main gold-bearing sulfide arsenic ores of the Bakyrchik gold deposit(Kazakhstan),related to post-collisional magmatic-hydrothermal *** mineralization of the deposit occurs mainly in the form of an“invisible”type of gold in the structures of arsenian pyrite and arsenopyrite,and the form of gold-organic compounds of pyrobitumen in carbonaceous-terrigenous sequences of Carboniferous *** and electron microscopic analysis,Raman and FT-Infrared analysis,mineralogical and three-step sequential extraction analysis(NH2OHHCl,H2O2,HNO3?HCl)has been carried out using 9 ore samples(from 3 different types of ores)for a comprehensive study of pyrobitumen and sulfide arsenic ores focusing mainly on organic *** sequentially extracted precious metal content of pyrobitumen reaches up to 7 ppm gold and other metals like Ag 4 ppm,pt 31 ppb,and pd 26 ppb,forming metal–organic compounds,while arsenic sulfide minerals incorporate 11 ppm gold,39 ppm Ag,0.49 ppm *** enrichment of gold associating with organic matter and sulfide ore minerals was confirmed in this *** matter was active in the migration of gold and the capture of gold by ***,the reductive organic matter agent released gold,most likely for the sulfide arsenic ore *** was a decisive factor in the concentration,transportation,and preservation of gold in the deposit.

关键词： Gold pyrobitumen Bakyrchik vitrinite Metal-organic compounds

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Laminar Forced Convection in Curved Channel with vortex Structures

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Journal of Thermal Science 2004年第2期13卷 143-149,162页

作者： A.A. AvRAMENKO S.G. KOBZAR I.v. SHEvCHUK A.v. KUZNETSOv B.I. BASOK Institute of Engineering Thermophysics National Academy of SciencesKievUkraine Center for Energy Research National University of MexicoAp.P.3462580TemixcoMor.Mexico Dept.of Mechanical and Aerospace Engineering North Carolina State UniversityCampus Box 7910RaleighNC 27606-7910USA

Theoretical and experimental investigations of heat transfer in flat curvilinear channel have been carried out. Linear and non-linear effects of Dean vortexes on intensity of heat transfer were taken into account. The linear effect, which describe harmonic (sinuous) variation of the heat transfer coefficient near the concave surface of the channel and the non-linear effect causes the general increase of the heat transfer coefficient due to augmentation of heat transfer engendered by the Dean vortexes. For both effects, mathematical relations were obtained in the form of quadratures. These numerical results were modified to the form convenient in engineering calculations. The investigations have shown that both linear and nonlinear components grow up with the Dean number. Nonlinear component Q0T increases more abruptly, while the linear one Q1T is more conservative. This is a confirmation of stability of vortex structures.

关键词： heat transfer Dean vortexes curvilinear channel quadrature.

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Multi-Constrained QoS Opportunistic Routing by Optimal power Tuning in Low Duty-Cycle WSNs

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Circuits and Systems 2016年第10期7卷 2928-2939页

作者： v. p. Jayachitra G. Geetha Durbaka Aishwarya Department of Computer Technology MIT Campus Anna University Chennai India Department of Computer Science & Engineering Jerusalem College of Engineering Anna University Chennai India

Designing a multi-constrained QoS (Quality of service) communication protocol for mission-critical applications that seeks a path connecting source node and destination node that satisfies multiple QoS constrains such as energy cost, delay, and reliability imposes a great challenge in Wireless Sensor Networks (WSNs). In such challenging dynamic environment, traditional routing and layered infrastructure are inefficient and sometimes even infeasible. In recent research works, the opportunistic routing paradigm which delays the forwarding decision until reception of packets in forwarders by utilizing the broadcast nature of the wireless medium has been exploited to overcome the limitations of traditional routing. However, to guarantee the balance between the energy, delay and reliability requires the refinement of opportunistic routing through interaction between underlying layers known as cross-layer opportunistic routing. Indeed, these schemes fail to achieve optimal performance and hence require a new method to facilitate the adoption of the routing protocol to the dynamic challenging environments. In this paper, we propose a universal cross-layered opportunistic based communication protocol for WSNs for guaranteeing the user set constraints on multi-constrained QoS in low-duty-cycle WSN. Extensive simulation results show that the proposed work, Multi-Constrained QoS Opportunistic routing by optimal power Tuning (mor-pT) effectively achieves the feasible QoS trade-off constraints set by user by jointly considering the power control and selection diversity over established algorithms like DSF [1] and DTpC [2].

关键词： Cross-Layer Transmission power Control Latency Control Energy Efficiency Network Throughput Multi-Hop Wireless Networks Mission Critical Applications

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Simulation of Waves processes in Dusty Emission of volcano

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Open Journal of Geology 2011年第1期1卷 10-16页

作者： v.v. Grimalsky M.A. Cruz Chavez S.v. Koshevaya A. Kotsarenko M. Hayakawa R. pérez Enriquez Autonomous University of morelos (UAEM) Cuernavaca ZP 62209 Mor. Mexico

A general method of simulation of processes in dusty based on special programs is presented here. It is pos-sible to prepare the modeling of the dusty in volcano like the dust sound waveguides. Dusty is in state of the plasma .Waveguides are formed by the distribution of dusty particles with various masses m = m(x) in trans-verse coordinate. The dust sound waves propagate along the longitudinal z-direction. In the case of contact of dusty plasma with a semi-infinite dielectric, there exists the dust acoustic mode that possesses the negative group velocity (backward wave) in the specified interval of wave numbers. For analysis it is necessary to use the special numerical methods of calculation of the equations with boundary conditions. Simulation of ion sound wave propagation shows a new dispersion between frequency and wave vector. In some region of pa-rameters of dusty the negative dispersion of wave takes place. This means that the phase and group velocities of wave are opposite (negative dispersion). This phenomenon takes place, when the mass of dust particles has the maximum in the center of the waveguide. The negative dispersion caused the instability in dusty, which open the possibility to create a new phenomenon in dusty including the high temperature and the flame.

关键词： Dusty plasma Dispersion Negative Group velocity

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Effect of Ablation Casting on Microstructure and Casting properties of A356 Aluminium Casting Alloy

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Acta Metallurgica Sinica(English Letters) 2013年第1期26卷 85-91页

作者： v. Bohlooli M. Shabani Mahalli S. M. A. Boutorabi Casting Research Center School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST)

Recently the Ablation Casting Technology was invented as a new casting process to improve foundry products quality. In this study, the effects of processing variables on the porosity content, rnicrostructure and feedability of A356 casting alloy were investigated. Secondary dendrite arm spacing （SDAS） and eutectic silicon mor-phologies were studied to evaluate the influence of Ablation Casting on the rnicrostructure. Casting density was measured in order to identify porosity content and feedability of ablated and non-ablated specimens. In addition, solidification behavior of the samples was investigated by using thermal analysis technique. The cooling curves and the first derivative curves were plotted and compared with each other. Results showed the ablation process could increase solidification rate significantly. In addition, the microstructural evidences revealed that Ablation Casting process results in more fine and homogeneous structure compared to the non-ablated casting. The feedability improved, SDAS reduced to 35% and porosity content decreased to 3.84 vol.% by implementing this process. It concluded the Ablation Casting is an effective process to gain higher quality in aluminum foundry.

关键词： Ablation Casting A356 aluminium alloy Microstructure porosity Cooling curve

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Compressive pericardial Teratoma about a Case at Regional Hospital of Saint Louis/Senegal

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Journal of Biosciences and Medicines 2022年第6期10卷 1-7页

作者： Serigne mor Beye Cheikh Ahmadou Bamba Samb Aicha Ndichout Ndeye Rokhaya Diop Khadimu Rassoul Diop Ansoumana Condé Joseph Salvador Mingou Jean Baptiste Mathieu Sy Adama Kane Departement of Cardiology Regional Hospital of Saint Louis City Senegal Departement of Radiology Regional Hospital of Saint Louis City Senegal

Introduction: Cardiac tumors in children are rare. Most are discovered in children under one year of age. Echocardiography is the basic examination for the screening, it allows their detection from the fetal stage. Observation: She was a 14-year-old patient with no known history of pathology. She was admitted to our department for the exploration of dyspnea and chest pain. At her admission, she had stable hemodynamics. At cardiac auscultation, heart sounds were muffled. The EKG recorded a sinus rhythm, and negative T-waves from v1 to v4. The chest X-ray showed cardiomegaly and a dense, rounded, heterogeneous left hilar opacity, well limited. Echocardiography objected to a great intrapericardial mass in front of the left cardiac cavities compressing part of the left atrium and left ventricle associated with an important pericardial effusion. The CT scan found a heterogeneous pericardial suspected myxoma mass. The pathological examination confirmed pericardial teratoma. The patient had an excision of the pericardial mass. The evolution after surgery was favorable. Conclusion: Intra-pericardial teratomas are benign tumor. Complete removal of the tumor is curative and without recurrence.

关键词： Teratoma pericardium Saint-Louis

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Synthesis, morphology and Magnetic Characterization of Zn Ferrite powders

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Journal of Electromagnetic Analysis and Applications 2010年第10期2卷 598-600页

作者： S. A. popescu p. vlazan p. v. Notingher S. Novaconi I. Grozescu A. Bucur p. Sfirloaga National Institute for Research and Development in Electrochemistry and Condensed Matter Timisoara Romania politehnica University of Bucharest Electrical Engineering Faculty Bucharest Romania

We synthesized Zn0.8Fe2.2O4 ferrite powders by coprecipitation and hydrothermal techniques and analyzed the mor-phology and magnetic properties. The morphology and structure of the Zn ferrite powders were investigated using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) identifying the crystallization planes. Magnetic hysteresis curves were obtained for the Zn ferrites samples.

关键词： Zn Ferrites Hysteresis morphology and Structure

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Indicators of success for smart law enforcement in protected areas:A case study for Russian Amur tiger(panthera tigris altaica)reserves

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Integrative Zoology 2016年第1期11卷 2-15页

作者： Michiel H.H.HÖTTE Igor A.KOLODIN Sergei L.BEREZNUK Jonathan C.SLAGHT Linda L.KERLEY Svetlana v.SOUTYRINA Galina p.SALKINA Olga Y.ZAUMYSLOvA Emma J.STOKES Dale G.MIQUELLE Wildlife Conservation Society BronxNew YorkUSA phoenix Fund VladivostokRussian Federation Zoological Society of London Regent’s ParkLondonEngland Sikhote-Alin Biosphere Zapovednik Primorskii KraiRussian Federation Lazovskii State Nature Zapovednik Primorskii KraiRussian Federation Department of Ecology Far Eastern Federal UniversityAyaksRusski Island

Although considerable conservation resources have been committed to develop and use law enforcement monitoring and management tools such as SMART,measures of success are ill-defined and,to date,few reports detail results ***,we present 4 case studies from protected areas with Amur tigers(panthera tigris altaica)in Russia,in which indicators of success were defined and evaluated at *** ultimate goal was an increase in tiger numbers to 1 individual/100 km^(2)at each *** predicted that improvements in law enforcement effectiveness would be followed by increases in prey numbers and,subsequently,tiger *** used short-term and long-term indicators of success,including:(i)patrol team effort and effectiveness;(ii)catch per unit effort indicators(to measure reductions in threats);and(iii)changes in target species *** addition to implementing a monitoring system,we focused on improving law enforcement management using an adaptive management *** 4 years,we noted clear increases in patrol effort and a partial reduction in *** we did not detect clear trends in ungulate numbers,tiger populations remained stable or increased,suggesting that poaching of tigers may be more limiting than prey *** effectiveness is needed before a clear reduction in threats can be noted,and more time is needed before detecting responses in target ***,delineation of concrete goals and indicators of success provide a means of evaluating progress and *** monitoring should be a central component of law enforcement strategies for protected areas.

关键词： adaptive patrol management Amur tiger anti-poaching law enforcement monitoring SMART

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