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Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen Simon Hettler Ashwin Ramasubramaniam raul Arenal Ronen Bar-Ziv Maya Bar Sadan Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel Department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

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Simplification workflow for hydraulically fractured reservoirs

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Petroleum 2018年第2期4卷 134-147页

作者： raul Velasco Palash Panja Milind Deo Energy&Geoscience Institute Salt Lake CityUSA Department of Chemical Engineering The University of UtahSalt Lake CityUSA

Production from unconventional formations,such as shales,has significantly increased in recent years by stimulating large portions of a reservoir through the application of horizontal drilling and hydraulic *** oil shales are heavily dependent on oil prices,production forecasts remain positive in the North-American *** to the complexity of hydraulically fractured tight formations,reservoir numerical simulation has become the standard tool to assess and predict production performance from these unconventional *** of these unconventional fields are immense,consisting of multistage and multiwell projects,which results in impractical simulation run ***,simplification of large-scale simulation models is now common both in the industry and *** simplified models such as the“single fracture”approach do not often capture the physics of large-scale projects which results in inaccurate *** this paper we present a simple,yet rigorous workflow that generates simplified representative models in order to achieve low simulation run times while capturing physical phenomena which is fundamental for accurate *** proposed workflow is based on consideration of representative portions of a large-scale model followed by postprocess scaling to obtain desired full model *** simplified models that result from the application of the proposed workflow for a single well and a multiwell case are compared to full-scale models and the“single fracture”*** of fluid rates and cumulative production show that accurate results are possible for simplified models if all important components for a particular case are taken into ***,application of the workflow is shown for a heterogeneous field case where prediction studies can be carried out.

关键词： Hydraulic fracture Shale Simulation workflow Multiwell Field case

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SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： raul Quijada Juan L.Guevara Rene Rojas Franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

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Body Composition,Aerobic Fitness,Isokinetic Profile,and Vertical Jump Ability in Elite Male and Female Volleyball and Beach Volleyball Players

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Journal of Science in Sport and Exercise 2023年第4期5卷 385-395页

作者： raul Freire Matheus Hausen Glauber Pereira Alex Itaborahy Olympic Laboratory Brazil Olympic CommitteeRio de JaneiroBrazil Laboratory of Biomechanics and Motor Behavior Institute of Physical Education and SportsRio de Janeiro State UniversityRio de JaneiroBrazil

Purpose This study aimed to compare the physical attributes of male and female Volleyball and Beach Volleyball *** Fifty-five athletes from Volleyball(Male,n=19,age 27.3±6.1 years,body mass 93.2±9.9 kg,and height 196.8±7.4 cm and Female,n=16,age 28.0±5.6 years,body mass 76.9±8.8 kg,and height 179.9±5.8 cm)and Beach Volleyball(Male,n=10,age 26.8±3.4 years,body mass 92.9±9.9 kg,and height 195.3±7.9 cm and Female,n=10,age 31.1±6.2 years,body mass 74.6±8.5 kg,and height 180.9±6.0 cm)participated in the *** tests were performed in a single visit to the laboratory in the following order:body composition,vertical jump(squat and countermovement jump),isokinetic(knees and shoulders),and cardiopulmonary exercise *** variables were analyzed using a two-way ANOVA(Sex and Sport factors)for independent *** Beach Volleyball athletes presented lower body fat(P=0.03;ES=0.32)and higher maximal cardiorespiratory variables(VO2,HR,and vVO2max).Only flexion bilateral difference(knee)at 60°/s was affected by sex(P=0.002;ES=0.63).For shoulders,only dominant external/internal rotation ratio presented a significant interaction for sport and sex(P=0.05;ES=0.28).Regarding vertical jumps,Volleyball male players presented a greater elastic index than BV male players(P=0.002,ES=0.67).Conclusion Beach Volleyball players are thinner and have better cardiorespiratory fitness than Volleyball ***,they presented less use of elastic properties for vertical jumping and have a greater muscle imbalance in the hamstrings than Volleyball players.

关键词： Athlete profile Court VO2max Neuromuscular Sex Sport

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Photometric and Spectroscopic Studies for Two Magnetic-activity Contact Binaries:V724 And and QR Com

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Research in Astronomy and Astrophysics 2022年第11期22卷 51-60页

作者： Shuang Wang raul Meichel Huiyu Yuan Yuangui Yang School of Physics and Electronic Information Huaibei Normal UniversityHuaibei City 235000China Observatorio Astronomico Nacional Instituto de AstronomiaUniversidad Nacional Autonoma de MexicoApartado Postal 877EnsenadaB.C.22830Mexico

We presented new CCD photometry for two contact binaries,V724 And and QR Com,which were observed during the 2020–2022 observing *** using the Wilson–Devinney method,the photometric solutions were deduced from new observed data and TESS *** asymmetric light curves were modeled by a dark spot on the more massive *** indicate that the starspot may immigrate or disappear on the surface of the active *** the TESS observations of QR Com,it is discovered that the difference between light maxima exhibits a 29.5 day oscillation,which implies the continuous evolution of spot feathers on the timescale of several *** mass ratio and fill-out factor are q=2.308 and f=11.55% for V724 And,and q=0.624 and f=12.77% for QR Com,*** the(O-C)curve,the orbital period secularly decrease at a rate of d P/dt=-1.66×10^(-7)day yr^(-1)for V724 And and d P/dt=-3.98×10^(-7)day yr^(-1)for QR Com,which was interpreted by mass transfer from the more massive component to the less massive *** period decreasing,this kind of shallow-contact binaries,V724 And and QR Com,will evolve into the deep-contact configurations.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:low-mass

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Research on the Countermeasures for the Development of the Tourism Hospitality Industry in Cape Verde

Research on the Countermeasures for the Development of the T...

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作者： raul Jorge Duarte Soule 合肥工业大学

学位级别：硕士

伴随着佛得角现代旅游的发展,佛得角旅游饭店业的发展已有10多年的历史。而到目前为止,关于佛得角饭店业的学术研究还很少。佛得角是非洲大陆非洲地区优质旅游地的代表,也是非洲旅游开发的龙头,而回顾佛得角市饭店业发展的历程,客观反... 详细信息

伴随着佛得角现代旅游的发展,佛得角旅游饭店业的发展已有10多年的历史。而到目前为止,关于佛得角饭店业的学术研究还很少。佛得角是非洲大陆非洲地区优质旅游地的代表,也是非洲旅游开发的龙头,而回顾佛得角市饭店业发展的历程,客观反映其发展现状及其面临的问题,结合发展的机遇探讨其发展中的对策,对佛得角旅游饭店业的可持续发展和非洲旅游的开发,都有重要的意义。本文采用了实地调研法、逻辑分析法、历史数据收集分析等方法,理论与实践相结合,通过深入的分析,为佛得角饭店业的发展提出了较为切实可行的具体对策。而实际的研究内容共分为三个部分:第一部分首先回顾了佛得角旅游经济产业全面开放以来佛得角市旅游饭店业的发展历程,从佛得角当地政府以及游客的角度将其分为两个发展阶段;其次,从饭店规模、饭店经济类型、星级饭店的构成、饭店经营等方面对佛得角市饭店业的现状进行了分析;同时还分析了其发展中呈现的特点。第二部分着重分析了佛得角市旅游饭店业面临的问题,指出在供过于求以及淡季时间长等因素的影响下小饭店面临的困境;第三部分,分别从宏观管理、行业管理和饭店企业经营管理这三个方面探讨了如何促进佛得角市饭店业的可持续发展。

关键词：佛得角旅游饭店业行业管理可持续发展

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Immunomodulatory oligonucleotide IMT504:Effects on mesenchymal stem cells as a first-in-class immunoprotective/immunoregenerative therapy

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World Journal of Stem Cells 2017年第3期9卷 45-67页

作者： Jorge Zorzopulos Steven M Opal Andrés Hernando-Insúa Juan M rodriguez Fernanda Elías Juan Fló Ricardo A López Norma A Chasseing Victoria A Lux-Lantos Maria F Coronel raul Franco Alejandro D Montaner David L Horn Immunotech S.A. Ciudad de Buenos Aires C1440FFXArgentina Infectious Disease Division Memorial Hospital of Rhode Island and Alpert Medical SchoolProvidenceRI 02905United States Fundación Pablo Cassara Ciudad Autonoma de Buenos Aires C1440FFXArgentina Instituto de Biología y Medicina Experimental(IBYME-CONICET) Ciudad Autónoma de Buenos Aires C1428ADNArgentina Instituto de Ciencia y Tecnolog'DR.Cesar Milstein” Fundación Pablo CassaráCiudad Autonoma de Buenos Aires C1440FFXArgentina David Horn LLC DoylestownPA 18902United States

The immune responses of humans and animals to insults(i.e., infections, traumas, tumoral transformation and radiation) are based on an intricate network of cells and chemical messengers. Abnormally high inflammation immediately after insult or abnormally prolonged proinflammatory stimuli bringing about chronic inflammation can lead to life-threatening or severely debilitating diseases. Mesenchymal stem cell(MSC) transplant has proved to be an effective therapy in preclinical studies which evaluated a vast diversity of inflammatory conditions. MSCs lead to resolution of inflammation, preparation for regeneration and actual regeneration, and then ultimate return to normal baseline or homeostasis. However, in clinical trials of transplanted MSCs, the expectations of great medical benefit have not yet been fulfilled. As a practical alternative to MSC transplant, a synthetic drug with the capacity to boost endogenous MSC expansion and/or activation may also be effective. Regarding this, IMT504, the prototype of a major class of immunomodulatory oligonucleotides, induces in vivo expansion of MSCs, resulting in a marked improvement in preclinical models of neuropathic pain, osteoporosis, diabetes and sepsis. IMT504 is easily manufactured and has an excellent preclinical safety record. In the small number of patients studied thus far, IMT504 has been well-tolerated, even at very high dosage. Further clinical investigation is necessary to demonstrate the utility of IMT504 for resolution of inflammation and regeneration in a broad array of human diseases that would likely benefit from an immunoprotective/immunoregenerative therapy.

关键词： Immunohomeostasis Immunoprotection Immunoregeneration Inflammation Mesenchymal stem cells IMT504

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Neuroinflammation and oxidative stress act in concert to promote neurodegeneration in the diabetic retina and optic nerve:galectin-3 participation

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Neural Regeneration Research 2020年第4期15卷 625-635页

作者： Henrique Rocha Mendonca raul Carpi-Santos Karin da Costa Calaza Ana Maria Blanco Martinez Laboratorio de Neurodegeneracao e Reparo Departamento de PatologiaPrograma de Pos-graduacao em Anatomia PatologicaFaculdade de MedicinaHospital Universitrio Clementino Fraga FilhoFederal University of Rio de JaneiroRio de JaneiroBrazil Polo Universitario Macae Unidade Integrada de Pesquisa em Produtos Bioativos e BiocienciasFederal University of Rio de JaneiroMacaeBrazil Laboratorio Integrado de Morfologia Instituto de Biodiversidade e SustentabilidadeNucleo de Pesquisas Ecologicas de MacaeFederal University of Rio de JaneiroMacaeBrazil Laboratorio de Neurobiologia Celular Instituto de Ciencias BiomedicasCentro de Ciencias da SaudeFederal University of Rio de JaneiroRio de JaneiroBrazil Laboratorio de Neurobiologia da Retina Departamento de NeurobiologiaPrograma de Pos-Graduacao em NeurocienciasFluminense Federal UniversityNiteroiBrazil

Diabetes is a lifelong disease characterized by glucose metabolic imbalance,in which low insulin levels or impaired insulin signaling lead to hyperglycemic *** 20 years of diabetes progression,95%of patients will have diabetic retinopathy,the leading cause of visual defects in working-age people *** diabetes is considered a microvascular disease,recent studies have shown that neurodegeneration precedes vascular changes within the diabetic visual system,albeit its mechanisms are still under *** and oxidative stress are intrinsically related phenomena,since macrophage/microglia and astrocytes are the main sources of reactive oxygen species during central nervous system chronic degenerative diseases,and both pathological processes are increased in the visual system during *** present review will focus on recent findings of the contribution of oxidative stress derived from neuroinflammation in the early neurodegenerative aspects of the diabetic visual system and their relationship with galectin-3.

关键词： diabetes diabetic retinopathy galectin-3 neurodegeneration neuroinflammation optic nerve oxidative stress retina

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Designing nanocarriers to overcome the limitations in conventional drug administration for Parkinson’s disease

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Neural Regeneration Research 2022年第8期17卷 1743-1744页

作者： Rafael A.García-Muñoz Joseph McConnell Victoria Morales raul Sanz Department of Chemical and Environmental Technology Rey Juan Carlos UniversityMadridSpain Department of Chemical&Process Engineering University of StrathclydeGlasgowUK

Neurodegenerative diseases(NDs)have become one of the leading causes of death and disability worldwide,and cause enormous pain and suffering for both patients and their *** of the most common NDs include Alzheimer’s disease,Parkinson’s disease(PD)and Huntington’s disease,among others(Feng,2020).PD is a widespread neurodegenerative disease that affects more than 10 million people worldwide(No author listed,2021).The direct cause of the disease is unknown,but it is characterized by the selective degeneration of dopaminergic neurons in the midbrain in the substantia *** leads to the depletion of dopamine(3,4-dihydroxyphenethylamine,DA)in the striatum of patients,in addition to the existence of abnormalα-synuclein in nerve cells and the development of toxic protein aggregates in neurons called Lewy bodies,which causes muscle stiffness,slowness of movements and *** is believed that a combination of genetic and environmental factors may be the cause of PD,but the exact reason for the disease is not yet fully understood.

关键词： Huntington degeneration overcome

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Synthesis of (B-C-N) Nanomaterials by Arc Discharge Using Heterogeneous Anodes

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Plasma Science and Technology 2016年第5期18卷 465-468页

作者： Djamel Eddine GOURARI Manitra RAZAFINIMANANA Marc MONTHIOUX raul ARENAL Flavien VALENSI Sebastien JOULIE Virginie SERIN LAPLACE (Laboratoire Plasma et Conversion d'Energie) CNRS-INPT-Universite Toulouse III 118 Route de Narbonne 31062 Toulouse Cedex 9 France CEMES (Centre d'Elaboration des Materiaux et d'Etudes Structurales) CNRS-Universite Toulouse III 29 rue Jeanne Marvig F-31055 Toulouse Cedex 4 France Instituto de Nanociencia de Aragon (INA) Universidad de Zaragoza Calle Mariano Esquillor 50018 Zaragoza Spain

In spite of the current prevalence of the CVD-based processes, the electric arc remains an interesting process for the synthesis of carbon nanoforms, thanks to its versatility, robustness and easiness. It also allows performing in-situ substitution of carbon atoms by hetero-elements in the graphene lattice. Our work aims to establish a correlation between the plasma properties, type and chemical composition （and the substitution rate） of the obtained single-wall carbon nan- otubes. The plasma was characterized by optical emission spectroscopy and the products were analyzed by high resolution transmission electron microscopy and core level Electron Energy-Loss Spectroscopy （EELS）. Results show that a high boron content leads to a plasma temperature decrease and hinders the formation of nanotubes. This effect can be compensated by increasing the arc current and/or yttrium content. The optimal conditions for the synthesis of boron- and/or nitrogen-substituted nanotubes correspond to a high axial plasma temperature associated to a strong radial gradient. EELS analysis confirmed that the boron incorporates into the graphenic lattice.

关键词： arc discharge plasma nanomaterials synthesis optical spectroscopy boronnitride doped carbon nanotubes HRTEM EELS

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