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An egg-shell bifunctional CeO_(2)-modified NiPd/Al_(2) O_(3) catalyst for petrochemical processes involving selective hydrogenation and hydroisomerization

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Journal of Rare Earths 2021年第11期39卷 1382-1388,I0003页

作者： Franklin J.Mendez Javier A.Alves Yahse Rojas-Challa Oscar Corona Yanet Villasana Julia Guerra German Garcia-Colli Osvaldo M.Martinez joaquin l.brito Centro de Quimica Instituto Venezolano de Invesdgaciones CientfficasCarretera PanamericanaKm 11 Altos de PipeCaracas1020AVenezuela Departamento de Estado Solido Instituto de FisicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico04510Mexico Departamento de Ingenieria Quimica Facultad de Ingenieria(UNLP)and Centro de Investigacion y Desarrollo en Ciencias Aplicadas"Dr.J.J.Ronco"(CINDECA)CCT-La Plata-CONICET-UNLPLa Plata1900Argentina Departamento de Quimica Analitica Facultad de QufmicaUniversidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico04510Mexico Instituto Tecnoldgico Venezolano Del Petroleo SA. Petrole os de Venezuela SA.Urb.Santa Rosa-Sector El TamborLos Teques1201Venezuela Instituto Superior de Formacion Docente Salome Urena Esquina Leonardo D'VinciSanto Domingo10114Republica Dominicana Biomass to Resources Group Universidad Regional Amazonica IkiamKm 7 via MuyunaTena150150Ecuador Departamento de Termodinamica y Fenomenos de Transferencia Universidad Simon BolivarValle de SartenejasCaracas1086Venezuela

The catalytic performance during the 1-butyne hydrogenation using two reduced Al_(2) O_(3)-supported Pdbased catalysts was carried out in a total recirculation system with an external fixed-bed reactor.The lab-prepared egg-shell NiPd/CeO_(2)-Al_(2) O_(3) catalyst(NiPdCe) with Pd loading=0.5 wt%,Ni/Pd atomic ratio=1 and CeO_(2) loading=3 wt% was synthesized and characterized,and it was compared with an egg-shell Al_(2) O_(3)-supported Pd based commercial catalyst(PdCC).The reduced catalysts were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and high-resolution transmission electron microscopy.The textural characteristics and ammonia temperature-programmed desorption profiles of the fresh(unreduced) catalysts were also obtained.Both catalysts show high 1-butyne conversion and selectivity to 1-butene,but the catalysts also present important differences between hydroisomerizing and hydrogenating capabilities.NiPdCe catalyst shows higher capability for hydroisomerization reactions,while the PdCC catalyst exhibits higher hydrogenating capability.The observed catalytic performances can be interesting for some industrial processes and can provide a guideline for the development of a Pd-based catalyst with specific catalytic properties.

关键词： 1-Butyne Bifunctional catalyst Egg-shell Hydrogenation Hydroisomerization NiPd catalyst

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Colon Adenocarcinoma in a Retrograde Intussusception: A Case Report and literature Review

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Open Journal of Gastroenterology 2024年第5期14卷 153-160页

作者： Carlos Hernández brito Pedro Arredondo Ruiz Brenda Paola Sáenz Dávila Arsenio Torres Delgado luis Eduardo Méndez Turrubiates luis Ángel Amezcua Toledo Omar Josué Herrera lópez Surgical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Clinical Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico General and laparoscopic Surgery Corporativo M&#233dico-Quir&#250rgico Torres Veracruz Mexico Radiation Oncology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Radiology Department Centro Oncol&#243gico Onkolid Veracruz Mexico Anatomical Pathology Department Centro Oncol&#243gico Onkolid Veracruz Mexico

Background: Intussusception is defined as a telescoping of a proximal gastrointestinal segment with its mesentery to a distal one, only 5% occur in adults and in colon the probability that it is caused by a malignant disease is up to 65%. Only 1% occurs in a retrograde manner, the rest occur in an anterograde manner. Aim: Describe the clinical presentation of an intussusception in the adult patient as well as its most frequent causes and possible complications that influence decision making for a definitive treatment. Case Presentation: A 66-year-old woman diagnosed with colon adenocarcinoma who underwent elective transverse colectomy and colonic anastomosis with an incidental finding of a transverse colon tumor in a retrograde intussusception was studied. Conclusion: In any adult patient with an intussusception especially in colon a neoplasia should be suspected and the affected segment should be resected without being reduced due to the risk of perforation and tumor dissemination.

关键词： Colon Cancer Colon Adenocarcinoma Colonic Intussusception Intussusception

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Nesting innovations allow population growth in an invasive population of rose-ringed parakeets

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Current Zoology 2022年第6期68卷 617-626页

作者： Dailos HERNANDEZ-brito Jose l.TEllA Guillermo BlANCO Martina CARRETE Department of Conservation Biology Donana Biological Station(CSIC)Calle Americo Vespucio26Sevilla 41092Spain Department of Evolutionary Ecology Museo Nacional de Ciencias Naturales(CSIC)Calle JoseGutierrez Abascal2Madrid 28006Spain Department of Physical Chemical and Natural SystemsUniversidad Pablo de OlavideCarretera de Utrerakm 1Sevilla 41013Spain

Certain traits of recipient environments,such as the availability of limiting resources,strongly determine the establishment success and spread of non-native species.These limitations may be overcome through behavioral plasticity,allowing them to exploit alternative resources.Here,we show how a secondary cavity nester bird,the rose-ringed parakeet Psittacula krameri,innovates its nesting behavior as a response to the shortage of tree cavities for nesting in its invasive range in Tenerife(Canary Islands).We observed that some breeding pairs excavated their own nest cavities in palms,thus becoming primary cavity nester,whereas others occupied nests built with wood sticks by another invasive species,the monk parakeet Myiopsitta monachus.The use of these novel nesting strategies increased the number of breeding pairs by up to 52%over 6 years,contributing to a 128.8%increase of the whole population.Innovative nests were located at greater heights above ground and were more aggregated around conspecifics but did not result in greater breeding success than natural cavities.Occupation of monk parakeet colonies by rose-ringed parakeets also benefited the former species through a protective-nesting association against nest predators.Our results show how an invasive species innovate nesting behaviors and increase nest-site availability in the recipient environment,thus facilitating its population growth and invasion process.Potential behavioral innovations in other invasive rose-ringed parakeet populations may be overlooked,and should be considered for effective management plans.

关键词： antipredator response behavioral flexibility biological invasions cavity nesters nesting innovation reproductive success

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深海环境海洋生态系统监测与修复新技术

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Engineering 2024年第3期34卷 195-211页

作者： Jacopo Aguzzi laurenz Thomsen Sascha Flögel Nathan J.Robinson Giacomo Picardi Damianos Chatzievangelou Nixon Bahamon Sergio Stefanni Jordi Grinyó Emanuela Fanelli Cinzia Corinaldesi joaquin Del Rio Fernandez Marcello Calisti Furu Mienis Elias Chatzidouros Corrado Costa Simona Violino Michael Tangherlini Roberto Danovaro Instituto de Ciencias del Mar(ICM-CSIC) Barcelona 08003Spain Stazione Zoologica Anton Dohrn Naples 80121Italy University of Gothenburg Göteborg 40530Sweden GEOMAR Helmholtz Centre for Ocean Research Kiel 24148Germany Fundación Oceanogràfic de la Comunitat Valenciana Valencia 46013Spain Royal Netherlands Institute for Sea Research(NIOZ) Den Burg Texel 1790 ABNetherlands Polytechnic University of Marche(UNIVPM) Ancona 60131Italy SARTI-MAR of the Universitat Politecnica de Catalunya(UPC) Vilanova i la Geltrú08800Spain lincoln Institute for Agri-food Technology University of LincolnLincoln LN22LGUK Engitec Systems International limited Limassol 3083Cyprus Consiglio per la Ricerca in Agricoltura e l’analisi Dell’economia Agraria(CREA) Centro di Ricerca Ingegneria e Trasformazioni AgroalimentariMonterotondo 00015Italy

The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural ecosystems.Marine ecosystem restoration is increasingly necessary due to increasing habitat degredation in deep waters(>200 m depth).At these depths,which are far beyond those accessible by divers,only established and emerging robotic platforms such as remotely operated vehicles(ROVs),autonomous underwater vehicles(AUVs),landers,and crawlers can operate through manipulators and multiparametric sensor arrays(e.g.,optoacoustic imaging,omics,and environmental probes).The use of advanced technologies for deep-sea ecosystem restoration can provide:①high-resolution three-dimensional(3D)imaging and acoustic mapping of substrates and key taxa,②physical manipulation of substrates and key taxa,③real-time supervision of remote operations and long-term ecological monitoring,and④the potential to work autonomously.Here,we describe how robotic platforms with in situ manipulation capabilities and payloads of innovative sensors could autonomously conduct active restoration and monitoring across large spatial scales.We expect that these devices will be particularly useful in deep-sea habitats,such as①reef-building cold-water corals,②soft-bottom bamboo corals,and③soft-bottom fishery resources that have already been damaged by offshore industries(i.e.,fishing and oil/gas).

关键词： Ecosystem restoration Robotic manipulation Acoustic tracking Fishery resources Artificial reefs

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Journal of Energy Chemistry 2022年第10期31卷 88-113,I0003页

作者： Magno B.Costa Moisés A.de Araújo Marcos V.de lima Tinoco Juliana F.de brito lucia H.Mascaro Departamento de Química Universidade Federal de São CarlosRodovia Washington Luizkm 235São CarlosSão Paulo 13565-905Brazil Instituto de Química de São Carlos Universidade de São PauloAvenida Trabalhador Sancarlense400São CarlosSão Paulo 13566-590Brazil Instituto de Química Universidade Estadual PaulistaRua Professor Francisco Degnis/nAraraquaraSão Paulo 14800-900Brazil

This review shows the importance of WO_(3)photoanode as a potentially low-cost,efficient,stable,and photoactive material for light-driven water splitting.For such,this manuscript aims to review the most recent publications regarding the strategies to improve the phoelectroactivity of WO_(3)films for water oxidation.In addition,this review aims to graphically highlight and discuss the general trendings of the photocurrent density response and stability test of the recent outstanding studies in the literature for photoelectrochemical water splitting application.The strategies covered in this review will not only concern the WO_(3)morphology and crystal plane growth,but also the many arrangements possibilities to improve the WO_(3)efficiency for water photoelectrooxidation,such as defect engineering based on oxygen vacancies,doping,decorations,and homo and heterojunctions.All these strategies are compared by the photocurrent density results and by the stability of these photocatalysts.The best results in this sense were observed in cases where the use of heterojunction was applied together with a desired morphology and crystal plane of the WO_(3)photoanode.However,the modifications that caused a decrease in the photocurrent density reaching values that are even lower than the pure WO_(3)were also discussed.In this way,this review intends to improve the knowledge about the synthesis and design of WO_(3)photoanodes to further obtain an efficient photocatalyst to minimize the recombination losses or losses across the interfaces and improve the photoelectroactivity for water splitting in the large-scale application.

关键词： Solar energy H_(2)production N-type semiconductor Photoelectrode design Oxygen evolution reaction

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Current concepts on osteonecrosis of the femoral head

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世界骨科杂志：英文版 2015年第8期6卷 590-601页

作者： joaquin Moya-Angeler Arianna l Gianakos Jordan C Villa Amelia Ni Joseph M lane Hospital for Special Surgery

It is estimated that 20000 to 30000 new patients are diagnosed with osteonecrosis annually accounting for approximately 10% of the 250000 total hip arthroplasties done annually in the United States. Thelack of level 1 evidence in the literature makes it difficult to identify optimal treatment protocols to manage patients with pre-collapse avascular necrosis of the femoral head, and early intervention prior to collapse is critical to successful outcomes in joint preserving procedures. There have been a variety of traumatic and atraumatic factors that have been identified as risk factors for osteonecrosis, but the etiology and pathogenesis still remains unclear. Current osteonecrosis diagnosis is dependent upon plain anteroposterior and frog-leg lateral radiographs of the hip, followed by magnetic resonance imaging(MRI). Generally, the first radiographic changes seen by radiograph will be cystic and sclerotic changes in the femoral head. Although the diagnosis may be made by radiograph, plain radiographs are generally insufficient for early diagnosis, therefore MRI is considered the most accurate benchmark. Treatment options include pharmacologic agents such as bisphosphonates and statins, biophysical treatments, as well as joint-preserving and joint-replacing surgeries. the surgical treatment of osteonecrosis of the femoral head can be divided into two major branches: femoral head sparing procedures(FHSP) and femoral head replacement procedures(FHRP). In general, FHSP are indicated at pre-collapse stages with minimal symptoms whereas FHRP are preferred at post-collapse symptomatic stages. It is difficult to know whether any treatment modality changes the natural history of core decompression since the true natural history of core decompression has not been delineated.

关键词： Osteonecrosis Femoral head Conservative treatment Core decompression Stem cells Total hip arthroplasty

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Endoscopic mucosal ablation-an alternative treatment for colonic polyps:Three case reports

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World Journal of Gastroenterology 2020年第45期26卷 7258-7262页

作者： Antonio Mendoza ladd joaquin Espinoza Cesar Garcia Department of Internal Medicine Division of GastroenterologyTexas Tech University Health Sciences CenterPaul L Foster School of MedicineEl PasoTX 79905United States Escuela de Medicina luis Razetti Universidad Central de VenezuelaCaracas 999188Venezuela Department of Endoscopy University Medical Center of El PasoEl PasoTX 79905United States

BACKGROUND Endoscopic resection of non-invasive lesions is now the standard of care for lesions in the GI tract.However,resection techniques require extensive training,are not available in all endoscopy centers and are prone to complications.Endoscopic mucosal ablation(EMA)is a combination of resection and ablation techniques and it may offer an alternative in the management of such lesions.CASE SUMMARY In this case series we report the successful treatment of three flat colonic polyps using the EMA technique.Two lesions were treatment naïve and 1 was a recurrence after an endoscopic mucosal resection.The sizes ranged from 2 to 4 cm.All three polyps were ablated successfully with no immediate or delayed complications.The recurrence rate at 1 year of follow up was 0%.CONClUSION Based on this initial experience,we conclude that EMA is a safe and effective technique for the treatment of non-invasive colonic polyps when endoscopic resection techniques are not available.

关键词： Endoscopy Mucosal ablation Colon polyp Argon plasma coagulation Alternative Safe Case report

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luminescence investigation of Dy2O2S and Dy2O2SO4 obtained by thermal decomposition of sulfate hydrate

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Journal of Rare Earths 2016年第8期34卷 814-819页

作者： R.V.Rodngues l.Marciniak l.U.Khan J.R.Matos H.F.brito W.Strek Institute of Chemistry University of Sao Paulo Butanta 748 26077 Sao Paulo Brasil Institute of low Temperature and Structure Research University of Wroctaw Oko1na 250-422 Wroclaw Poland

The yellow emitting dysprosium oxysulfide （Dy2O2S） and dysprosium oxysulfate （Dy202SO4） compounds were prepared from the thermal decomposition of hydrated dysprosium sulphate. The materials were characterized by using thermogravimetry （TG/DTG）, X-ray powder diffraction （XRD）, Fourier transform infrared （FTIR） and Raman spectroscopies. The thermal stability temperatures at around 1151 and 1313 K were determined for the Dy202S and Dy202SO4 materials, respectively. The photolumines- cence properties of the dysprosium oxysulfide were investigated, showing narrow emission bands assigned to the 4F9/2----＊6HJ intracon- figurational transitions of the Dy3＋ ion. The yellow emission color of this phosphor suggests that the Dy202S is a promising material for applications in lEDs.

关键词： Dy202S/Dy202SO4 sulfate thermal decomposition luminescence rare earths

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Determination of REE,U,Тh,Ba,and Zr in simulated hydrogeological leachates by ICP-AES after matrix solvent extraction

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Journal of Rare Earths 2009年第1期27卷 123-127页

作者： Marin Ayranov joaquin Cobos Karin Popa Vincenzo V.Rondinella European Commission Joint Research Centre Institute for Transuranium Elements Postfach 2340 76125 Karlsruhe Germany Paul Scherrer Institut CH-5232 Villigen PSI Switzerland "Al.I.Cuza"University Department of Chemistry 11-Carol I Blvd. 700506-Ia■i Romania

A fast, reliable and precise method for the determination of Ba, Zr, Th, U, la, Ce, Eu, Hf and Gd in leaching solutions containing up to 1 mol/l FeCl3 by inductively coupled plasma-atomic emission spectrometry（ICP-AES） was described.liquid-liquid extraction with diethyl ether was applied for selective and quantitative extraction of the iron with a decontamination factor of 65000.The study has enabled the determination of rare earth elements, U, Th Ba, and Zr, from the solution with high iron content with detection limits in the range of 1-24 ng/ml and a precision of 0.9%-4.6 % relative standard deviation.The developed method was simple and was adopted for implementation in a glove box for handling radioactive materials.

关键词： rare earths elements ICP-AES iron

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Projecting Extreme Changes in Summer Rainfall in South America by the Middle of the 21st Century

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Atmospheric and Climate Sciences 2014年第4期4卷 743-756页

作者： Paula Andrea M.Fonseca Jose Augusto P.Veiga Francis Wagner S.Correia Adriane l.brito Monica R.Queiroz Andre A.lyra Sin Chan Chou Post Graduation Program in Climate and Environment/National Institute for Amazonia Research(INPA)and Amazonas State University ManausBrazil Institute of Technology Amazonas State UniversityManausBrazil UNINORTE laureate International Universities ManausBrazil National Institute for Space Research(INPE) Cachoeira PaulistaBrazil

Extreme rainfall events can be considered a natural manifestation of the environment in which they are embedded and foreknowledge about their future behavior is very important, especially for decision makers. In this context, we aimed to explore the future behavior of extreme rainfall intensity through numerical simulations with the ETA model. The model was forced with a scenario of high greenhouse gas emissions for the middle of the 21st Century as described for A1B emission scenario. We detailed the main changes in accumulated rainfall produced by heavy events, very heavy events and rare events over a broad area of South America with a focus on the tropical sector. The methodology applied here is capable of separating extreme events and establishing the quantity of rainfall yielded by them. We have found that in the near future (2041-2050) rare events will tend to increase over the Amazon basin, followed by reductions in heavy and very heavy events. Conversely, heavy, very heavy and rare events are expected to decline over north-east Brazil. Furthermore, increases were found for heavy, very heavy and rare events over southern Brazil.

关键词： Climate Change Extreme Events Amazon South America

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