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materials Sciences and Applications 2012年第6期3卷 363-368页

作者： Daniele m.H.martinelli dulce m.a.melo Anne m.Garrido Pedrosa Antonio E.martinelli marcus A.de F.melo mary K.S.Batista Roberto C.Bitencourt Department of Chemistry Federal University of Rio Grande do NorteCCETNatalBrazil Department of Chemistry Federal University of SergipeCCETSao CristóvaoBrazil Research Center Petrobras—Cenpes Rio de JaneiroBrazil

In the current work, LaNiO3 perovskite was synthesized using the polymeric precursor method. The materials were thermally treated at 300°C for 2 hours, subsequently supported on alumina or zirconia and finally calcined at 800°C for 4 hours. The resulting samples were characterized by X-ray diffraction, thermogravimetry, BET surface area and thermo-programmed reduction. Steam reforming reactions were carried out at 750°C and 6 bar during 4 hours using a pilot reactor under a H2O:CH4 ratio of 2.5. The mass of catalysts was about 5.7 g. X-ray diffraction patterns confirmed the formation of the perovskite structure in all samples prepared. The results also showed that lanthanum nickelate was more efficient when supported on alumina than zirconia. Finally, it was observed that the methane conversion was approximately 94% and the selectivity to hydrogen was about 70%. In all cases low selectivity to CO and CO2 was verified.

关键词： Lanthanum Nickelate Perovskite Polymeric Precursor method Steam Reforming Reaction

Efficient removal of the recalcitrant metamizole contaminant from drinking water by using a CaLaCoO_(9) perovskite supported on recycled polyethylene

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Journal of Environmental Sciences 2024年第2期136卷 56-67页

作者： Ernesto Valadez-Renteria Christian Perez-Carrasco dulce Yolotzin medina-Velazquez Vicente Rodriguez-Gonzalez Jorge Oliva CONACYT-División de materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A.C.San Luis PotosíSLP 78216México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana AzcapotzalcoCol.Reynosa-TamaulipasC.P.MéxicoDF 02200México

metamizole(mZ)is a widely used anti-inflammatory *** to its common use,this contaminant is found in sewage and *** order to reduce the contamination produced by the mZ,we fabricated in this work a photocatalytic composite using recycled polyethylene(RPE)and the CaLaCoO_(9)(LCCO)*** nanoparticles had a microplate-like morphology and sizes of 1.4–5.5μm according to the analysis of *** photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible(UV-Vis)irradiation and found a removal efficiency of 96%.When the RPE+LCCO composite was employed for the photocatalytic degradation of mZ,a maximum degradation of 92.5%was *** influence of the pH on the photocatalytic activity was also studied and found that an initial pH=3 produced a total degradation of mZ after 240 min of UV-Vis ***,three reuse cycles were carried out for the pure LCCO powders and for the RPE+LCCO composites and found that the maximum loss of degradation was 5%.Furthermore,scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of ***,the X-ray photoelectron-spectroscopy and Raman analysis demonstrated the formation of defects(oxygen vacancies),those ones delayed the electron-hole recombination,which in turn,enhanced the degradation of the ***,the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds.

关键词： Photocatalysis metamizole Pharmaceutical contaminant UV-Vis irradiation Perovskite

Obstructive Sleep Apnea Hypopnea Syndrome and Pulmonary Embolism： Warfarin Versus Positive Airway Pressure as Determinant

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Chinese medical Journal 2016年第2期129卷 251-252页

作者： Filipa Ramalho Fernandes dulce Apolinario Antonio m Esquinas Department of Pneumoloqv Unidade Local de Saude da Guarda EPE - Sousa Martins Hospital Guarda Portugal Department of Pneumology Centro Hospitalar de Tras-os-Montes e Alto Douro EPE - Sao Pedro de Vila Real Hospital Vila Real Portugal Intensive Care and Non Invasive Ventilatory Unit Hospital Morales Meseguer Murcia Spain

To the Editor： Xie et al, analyzed warfarin doses in pulmonary embolism （PE） and its adverse effects in patients with obstructive sleep apnea hypopnea syndrome （OSAHS）. The key findings were that OSAHS patients required a significantly higher dose of warfarin than their non-OSAHS counterparts （4.73 mg vs. 3.61 mg, P 〈 0.001） and that PE recurrence was higher in OSAHS than in non-OSAHS groups after withdrawal ofwarfarin （21.43% vs. 6.78%, P = 0.047）.

关键词： analyzed warfarin pulmonary embolism great interest

Update on pathogenesis and clinical management of acute pancreatitis

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World Journal of Gastrointestinal Pathophysiology 2012年第3期3卷 60-70页

作者： dulce m Cruz-Santamaría Carlos Taxonera manuel Giner Department of Gastroenterology Hospital Clínico San Carlos Complutense University of Madrid28040 Madrid Spain Department of Surgery Hospital Clínico San Carlos Complutense University of Madrid28040 Madrid Spain

Acute pancreatitis (AP), defined as the acute nonbacterial inflammatory condition of the pancreas, is derived from the early activation of digestive enzymes found inside the acinar cells, with variable compromise of the gland itself, nearby tissues and other organs. So, it is an event that begins with pancreatic injury, elicits an acute inflammatory response, encompasses a variety of complications and generally resolves over time. Different conditions are known to induce this disorder, although the innermost mechanisms and how they act to develop the disease are still unknown. We summarize some well established aspects. A phase sequence has been proposed: etiology factors generate other conditions inside acinar cells that favor the AP development with some systemic events; genetic factors could be involved as susceptibility and modifying elements. AP is a disease with extremely different clinical expressions. most patients suffer a mild and limited disease, but about one fifth of cases develop multi organ failure, accompanied by high mortality. This great variability in presentation, clinical course and complications has given rise to the confusion related to AP related terminology. However, consensus meetings have provided uniform definitions, including the severity of the illness. The clinical management is mainly based on the disease′s severity and must be directed to correct the underlying predisposing factors and control the inflammatory process itself. The first step is to determine if it is mild or severe. We review the principal aspects to be considered in this treatment, as reflected in several clinical practice guidelines. For the last 25 years, there has been a global increase in incidence of AP, along with many advances in diagnosis and treatment. However, progress in knowledge of its pathogenesis is scarce.

关键词： Pancreas Pancreatitis Pathogenesis Treatment

Synthesis and Characterization of LaNixCo1-xO3 Perovskites via Complex Precursor methods

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materials Sciences and Applications 2010年第2期1卷 39-45页

作者： Grace Rafaela Oliveira Silva José Carlos Santos Danielle m. H. martinelli Anne michelle Garrido Pedrosa marcelo José Barros de Souza dulce maria Araujo melo 不详

This work presents a study on the synthesis of LaNixCo1-xO3 perovskites via complex precursor methods. Perovskite oxides with the composition LaNixCo1-xO3 were synthesized by chelating precursor and polymeric precursor methods using nickel and/or cobalt nitrates, lanthanum nitrate, ethylene glycol, citric acid, and EDTA as starting source. The obtained perovskite were characterized by thermogravimetric analysis, infrared spectroscopy, X-ray diffraction and the morphology of the samples were investigated by N2 adsorption experiments and average medium particle size. TG curves and FTIR spectra were particularly useful in establishing of the optimal calcination temperature of the precursor powders. X-ray diffraction patterns revealed the formation of the perovskite structure in all samples prepared by both synthesis method and after calcinations at 700℃. The results showed that the preparation method resulted in oxides with the intended structure. The specific surface area values were influenced by preparation method.

关键词： LaNixCo1-xO3 Perovskites EDTA Complex Precursor methods

Spatial Distribution of Nymphs Populations Bactericera cockerelli Sulc in Tomato Crops(Physalis ixocarpa Brot)

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Phyton-International Journal of Experimental Botany 2019年第4期88卷 449-458页

作者： Roberto Rivera-martínez Agustín David Acosta-Guadarrama JoséFrancisco Ramírez-Dávila Fidel Lara Vazquez dulce Karen Figueroa Figueroa Autonomous University of the State of mexico Cerrillo Piedras Blancas n/n km 15Toluca50200Mexico Laboratory of Entomology Research and Technology in Precision Farming UAEMCerrillo Piedras Blancas n/n km 15Toluca50200México

Tomato crops(Physalis ixocarpa Brot.)are produced in almost all mexico,part of the United States and Central *** the tomato production has suffered economic losses of 70%to 80%due the presence of yellowing and floral abortion,whose causal agent has been attributed to the presence of phytoplasma;an insect vector of these phytoplasma is Bactericera cockerrelli *** control of this psyllid has lacked effectiveness because their spatial distribution is unknown within tomato *** study aimed to determine the spatial distribution of populations of nymphs of *** in four tomato plots,the determination of the spatial distribution was performed by means of *** experimental semivariogram was determined to adjust to a theoretical model(spherical,exponential or Gaussian)through the program Variowin 2.2,the adjustment was validated with the method of cross-validation and aggregation maps of the pest were obtained through Kriging with Surfer 9.0 *** short-term time-space stability of the pest was determined through the tests Crámer-von *** results showed that populations of nymphs of *** have a distribution of aggregate type,which was corroborated by density *** are not present in 100%of the surface of the experimental plots,which helps to direct control measures on specific areas of infestation.

关键词： Geostatistics Bactericera cockerelli Sulc Kriging

Bubbling to Jetting Transition during Argon Injection in molten Steel

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World Journal of Engineering and Technology 2020年第4期8卷 605-616页

作者： miguel A. Barron Joan Reyes dulce Y. medina Departamento de materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

Bubbling to Jetting Transition is of the outmost importance in metallurgical processes given that the flow regime influences the refining rates, the refractory erosion, and the blockage of injection nozzles. Bubbling to jetting transition during subsonic bottom injection of argon in molten steel is studied here. The effect of the molten steel height, the injection velocity, the nozzle diameter, and the molten steel viscosity on the jet height and the bubbling to jetting transition is numerically analyzed using Computational Fluid Dynamics. Five subsonic argon injection velocities are considered: 5, 25, 50, 100 and 150 m/s. Three values of the metal height are taken into account, namely 1.5 m, 2 m and 2.5 m. Besides, three values of the nozzle diameters are considered: 0.001 m, 0.005 m and 0.01 m. Finally, three values of the molten steel viscosity are supposed: 0.0067, 0.1 and 1 kg/(m·s). It is observed that for the argon-molten steel system, the bubbling to jetting transition occurs for an injection velocity less than 25 m/s and that for the range of viscosities considered, the molten steel viscosity does not exert significant influence on the jet height and the bubbling to jetting transition. Due to the jet instability at subsonic velocities, a second transition, namely jetting to bubbling, is appreciated.

关键词： Argon Injection Bubbling to Jetting Transition CFD Injection Velocity Jet Height molten Steel Nozzle Diameter

Surface runoff and soil erosion in a natural regeneration area of the Brazilian Cerrado

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International Soil and Water Conservation Research 2020年第2期8卷 124-130页

作者： Karina dos Santos Falcao Elói Panachuki Felipe das Neves monteiro Roniedison da Silva menezes dulce B.B.Rodrigues Jullian Souza Sone Paulo Tarso S.Oliveira Department of Agronomy State University of Mato Grosso do SulAgronomy DepartmentAquidauanaMS79200-000Brazil Federal University of mato Grosso do Sul CxP 549Campo GrandeMS79070-900Brazil Department of Hydraulics and Sanitation Sao Carlos School of EngineeringUniversity of Sao PauloCxP.359Sao CarlosSP13566-590Brazil

The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic ***,the impacts of intense modification of land use and land cover on surface runoff and soil erosion are still poorly un-derstood in this ***,we assessed surface runoff and soil loss in a woodland Cerrado area under a former pasture area,which was abandoned and has undergone a natural regeneration process for 7 years(RC).Its results were compared with that found in an undisturbed area of woodland Cerrado(CE),40-month-old eucalyptus(3.0×1.8 m)(EU),and pasture under rotational grazing(PA).The study was conducted on Red Acrisol located in the Brazilian *** performed rainfall simulations on a plot of 0.7 m2 and using three constant rainfall intensities of 60,90,and 120 mm h-1 for 1 *** each rainfall intensity,we carried out four repetitions using different plots in each treatment,i.e.12 plots per treat-ment studied and 48 plots in *** noted that the soil physical properties were improved in RC and,consequently,water infiltration and soil erosion control;RC presented surface runoff and soil loss different from EU and PA(a=0.05).The macroporosity and soil bulk density affected surface runoff in RC and PA because the RC was used as pasture and is currently regenerating back to the cerrado *** the rainfall intensity increased,EU became more similar to PA,which showed the highest surface runoff and soil *** findings indicate that natural regeneration processes(pasture to the cerrado vegetation)tend to improve the soil ecosystem services,improving infiltration and reducing surface runoff and soil erosion.

关键词： Cerrado deforestation Forest regeneration Soil erosion

Neuroprotective effect of immunomodulatory peptides in rats with traumatic spinal cord injury

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Neural Regeneration Research 2021年第7期16卷 1273-1280页

作者： dulce Parra-Villamar Liliana Blancas-Espinoza Elisa Garcia-Vences Juan Herrera-García Adrian Flores-Romero Alberto Toscano-Zapien Jonathan Vilchis Villa Rodríguez Barrera-Roxana Soria Zavala Karla Antonio Ibarra Raúl Silva-García Unidad de Investigación médica en Inmunología Hospital de PediatríaCentro Médico Nacional Siglo XXI/Instituto Mexicano del Seguro Social/Ciudad de MéxicoMéxico Centro de Investigación en Ciencias de la Salud(CICSA) Facultad de Ciencias de la SaludUniversidad Anáhuac MéxicoCampus NorteHuixquilucanEdo de MéxicoMéxico Centro de Investigación del Proyecto Camina A.C Ciudad de MéxicoMéxico

Several therapies have shown obvious effects on structural conservation contributing to motor functional recovery after spinal cord injury(SCI).Nevertheless, neither strategy has achieved a convincing *** purposed a combined therapy of immunomodulatory peptides that individually have shown significant effects on motor functional recovery in rats with *** objective of this study was to investigate the effects of the combined therapy of monocyte locomotion inhibitor factor(mLIF), A91 peptide, and glutathione monoethyl ester(GSH-mEE) on chronic-stage spinal cord *** Sprague-Dawley rats underwent a laminectomy of the T9 vertebra and a moderate *** groups were included: sham, PBS, mLIF + A91, mLIF + GSH-mEE, A91 + GSH-mEE, and mLIF + A91 + *** months after injury, motor functional recovery was evaluated using the open field *** and white matter preservation was evaluated using hematoxylin & eosin staining and Luxol Fast Blue staining, *** number of motoneurons in the ventral horn and the number of axonal fibers were determined using hematoxylin & eosin staining and immunohistochemistry, *** deposition was evaluated using masson's trichrome *** combined therapy of mLIF, A91, and GSH-mEE greatly contributed to motor functional recovery and preservation of the medullary parenchyma, white matter, motoneurons, and axonal fibres, and reduced the deposition of collagen in the lesioned *** combined therapy of mLIF, A91, and GSH-mEE preserved spinal cord tissue integrity and promoted motor functional recovery of rats after *** study was approved by the National Commission for Scientific Research on Bioethics and Biosafety of the Instituto mexicano del Seguro Social under registration number R-2015-785-116(approval date November 30, 2015) and R-2017-3603-33(approval date June 5, 2017).

关键词： glutathione monoethyl ester monocyte locomotion inhibitor factor motor functional recovery neuroprotection neurorestoration peptides protective autoimmunity spinal cord injury

CFD Analysis of Influence of Slag Viscosity on the Splashing Process in an Oxygen Steelmaking Converter

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modeling and Numerical Simulation of material Science 2013年第3期3卷 90-93页

作者： miguel A. Barron dulce Y. medina Isaias Hilerio Departamento de materiales Universidad Autonoma Metropolitana Azcapotzalco M&eacutexico D.F. M&eacutexico

Physical properties of molten slag such as viscosity, density and surface tension have a significant influence on the slag splashing process in an oxygen steelmaking converter. Particularly, viscosity determines the shear forces that rule droplets formation. Besides, stirring of the molten slag bath strongly depends on this property. In this work, the influence of viscosity on the efficiency of slag splashing is explored by means of transient Computational Fluid Dynamics simulations. Several values of viscosity are employed in the computer experiments. In order to quantify the splashing efficiency as function of slag viscosity, an average slag fraction on the converter walls is defined and calculated. CFD results are compared with those of an empirical expression, and at least qualitative agreement is found.

关键词： CFD Oxygen Steelmaking Refractory Lining Slag Viscosity Splashing Process