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杂原子修饰的碳纳米管对高级氧化过程的催化性能(英文)

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催化学报 2014年第6期35卷 896-905页

作者： Joo Restivo Raquel p.rocha Adrián M.T.Silva José J.M.órfo Manuel F.R.pereira José L.Figueiredo Laboratory of Catalysis and Materials-Associate Laboratory LSRE/LCM Faculty of Engineering University of Porto Rua Dr.Roberto Frias 4200-465 Porto Portugal

Multi-walled carbon nanotubes (CNTs) were submitted to chemical and thermal treatments in order to incorporate different heteroatoms on the surface. O-, S- and N-containing groups were successfully introduced onto the CNTs without significant changes of the textural properties. The cata-lytic activity of these heteroatom-modified CNTs was studied in two liquid phase oxidation processes: catalytic ozonation and catalytic wet air oxidation (CWAO), using oxalic acid and phenol as model compounds. In both cases, the presence of strongly acidic O-containing groups was found to decrease the catalytic activity of the CNTs. On the other hand, the introduction of S species (mainly sulfonic acids) enhanced the removal rate of the model compounds, particularly in the CWAO of phenol. Additional experiments were performed with a radical scavenger and sodium persulfate, in order to clarify the reaction mechanism. Nitrogen functionalities improve the catalytic performance of the original CNTs, regardless of the process or of the pollutant.

关键词：多壁碳纳米管催化性能高级氧化技术杂原子修饰模型化合物含氮基团催化湿式氧化

Microstructural evolution during unsteady-state horizontal solidification of Al-Si-Mg(356) alloy

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1073-1083页

作者： J.O.LIMA C.R.BARBOSA I.A.B.MAGNO J.M.NASCIMENTO A.S.BARROS M.C.OLIVEIRA F.A.SOUZA O.L.rocha Federal Institute of Education Science and Technology of Para IFPA 66093-220 Belem PA Brazil Federal University of para Institute of Technology UFPA 66075-110 Belem PA Brazil

The increasing demand for reducing vehicle weight in the automotive and aerospace industries has raised the need to develop improved structural aluminum-based alloys. Thus, horizontal solidification experiment with the Al-7%Si-0.3%Mg（mass fraction） alloy was carried out. A water-cooled horizontal directional solidification device was developed and used. Microstructural characterization was carried out using traditional techniques of metallography, optical microscopy and SEM microscopy. The Thermo-Calc software was used to generate the solidification path of the investigated alloy with addition of 0.17% Fe（mass fraction）. The effects of the thermal parameters such as the growth rate（VL）, cooling rate（TC） and solidification local time（tSL） on the formation of the macrostructure and on the dendritic microstructure evolution were evaluated. A columnar to equiaxed transition（CET） was found for VL and TC values from 0.82 to 0.98 mm/s and from 1.71 to 2.55 ℃/s, respectively. The microstructure was characterized by the measurement of the primary and secondary dendrite arm spacings（λ1 and λ2, respectively）. Experimental laws of λ1 =f（VL, TC） and λ2 =f（tSL） were proposed. It is observed that the interdendritic region is composed of the following eutectic mixture： a（Al）＋Si＋p-Al8 Mg3 Fe Si6＋q-Mg2 Si.

关键词： Al-Si-Mg alloy microstructural transition dendrite arm spacing transient heat flow

Lycopene Supplementation Attenuates Oxidative Stress parameters in the plasma of Humans with Cad after Intense Exercise

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Food and Nutrition Sciences 2011年第4期2卷 241-248页

作者： Marília C. Araujo Fernanda S. Soares Merieli M. Ronsani Luiz G. C. rocha Lilian C. Vieira Luciano A. Silva Tales de Carvalho Magnus Benetti Ricardo A. pinho 不详

To investigate the effects of moderate and intense exercise (ME,IE) and lycopene (L) supplementation on oxidative stress biomarkers in patients with CAD. Rehabilitation ***-two male volunteers with CAD (55.65 ? 2.27 years, 77.27 ? 3.95 kg, 171.9 ? 2.80 cm) were divided into four groups;ME-placebo (n = 7), ME + L (n = 8), IE-placebo (n = 8) and IE-L (n = 9). Blood samples (12 mL) were collected before supplementation (one cereal bars – 15 mg of syn-thetic lycopene) and exercise (45 min plus 15 min of stretching, 3/wk) and after five weeks of supplementation and 72 h after exercise. Nitrite/nitrate concentrations (NOx), lipoperoxidation (TBARS levels), protein carbonylation (pC) and superoxide dismutase (SOD) and catalase (CAT) activity were assessed in plasma. NOx decreased significantly in the ME-p, IE-p and ME-L groups at 72 h after exercise and increased in the IE-L 72 h after the last exercise session. The IE-L group demonstrated decreased TBARS at 72 h after the last exercise session. The level of pC increased only in EI-p at 72 h after the last exercise session, while only the EI-L group presented a reduction. SOD increased signifi-cantly in both placebo groups 72 h after the last exercise session and decreased in the ME-L group 72 h after in rela-tion to placebo groups. CAT increased in ME-p, IE-p and IE-L groups only at 72 h after the last exercise session. The lycopene supplementation attenuates some markers of oxidative stress associated with IE Lycopene also had dissimilar effects on some markers of oxidative stress in subjects undertaking ME versus IE.

关键词： Lycopene Coronary Artery Disease Oxidative Stress Nitric Oxide Intense Exercise

Fast Radio Bursts as Crustal Dynamical Events Induced by Magnetic Field Evolution in Young Magnetars

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Research in Astronomy and Astrophysics 2022年第3期22卷 39-46页

作者： J.E.Horvath p.H.R.S.Moraes M.G.B.de Avellar L.S.rocha Universidade de São paulo(USp) Instituto de AstronomiaGeofísica e Ciências AtmosféricasRua do Matão 1226Cidade Universitária05508-090 São PauloSPBrazil Universidade Federal de São paulo(UNIFESp) Instituto de Ciências AmbientaisQuímicas e FarmacêuticasRua São Nicolau 21009913-030 DiademaSPBrazil Universidade Federal do ABC(UFABC) Centro de Ciências Naturais e Humanas(CCNH)Avenida dos Estados 500109210-580Santo AndréSPBrazil

We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar’s *** address the basics of such a model by solving the propagation of the perturbation approximately,and quantify the energetics and the radiation by bunches of charges in the so-called charge starved region in the ***(almost)simultaneous emission of newly detected X-rays from SGR 1935+2154 is tentatively associated with a reconnection behind the *** strength of f-mode gravitational radiation excited by the event is quantified,and more detailed studies of the nonlinear(spiky)soliton solutions are suggested.

关键词： stars:magnetars relativistic processes radiation mechanisms:non-thermal

The spike protein of SARS-CoV-2 variant A.30 is heavily mutated and evades vaccine-induced antibodies with high efficiency

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Cellular & Molecular Immunology 2021年第12期18卷 2673-2675页

作者： prerna Arora Cheila rocha Amy Kempf Inga Nehlmeier Luise Graichen Martin S.Winkler Martin Lier Sebastian Schulz Hans-Martin Jäck Anne Cossmann Metodi V.Stankov Georg M.N.Behrens Stefan pöhlmann Markus Hoffmann Infection Biology Unit German Primate CenterKellnerweg 437077GöttingenGermany Faculty of Biology and psychology Georg-August-University GöttingenWilhelmsplatz 137073GöttingenGermany Department of Anesthesiology University of Göttingen Medical CenterGeorg-August University of GöttingenRobert-Koch-Straße 4037075GöttingenGermany Division of Molecular Immunology Department of Internal Medicine 3Friedrich-Alexander University of Erlangen-NürnbergGlückstraße 691054ErlangenGermany Department for Rheumatology and Immunology Hannover Medical SchoolCarl-Neuberg-Straße 130625HannoverGermany

The COVID-19 pandemic,caused by SARS-CoV-2,continues to rage in many countries,straining health systems and *** protect against severe disease and death and are considered central to ending the ***-19 vaccines(and SARS-CoV-2 infection)elicit antibodies that are directed against the viral spike(S)protein and neutralize the ***,the emergence of SARS-CoV-2 variants with S protein mutations that confer resistance to neutralization might compromise vaccine efficacy[1].

关键词： antibodies vaccine death

Technology for the production of Sorghum for Grain in the Vertisols of Campeche, Mexico

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Agricultural Sciences 2021年第6期12卷 666-683页

作者： Juan Medina-Méndez Jesús Manuel Soto-rocha Mirna Hernández-pérez Joaquín Gómez-Tejero Instituto Nacional de Investigaciones Forestales Agrícolas y pecuarias Campo Experimental Edzná Campeche México

This research was conducted in the state of Campeche, Mexico, between 2017 and 2018. On the one hand, the sorghum yield was explored in plots with Vertisol-type soils, which were supplied with rainwater. This had the purpose of knowing the results obtained by the producers in the area. On the other hand, an experiment was established with three factors: the genetic material of sorghum, planting density and fertilization. Finally, different varieties of soybeans and sorghum hybrids were also tested in large plots, to identify those that are best adapted to crop rotation. In the farmers’ plots, the grain yield was between 4377 and 5543 kg∙hap>−1p>. The planting density was from 142,667 to 197,334 plants per hectare, which indicated that, for each unit that increased the planting density, the yield increased by 37.5 grams. The experiment with three factors indicated that the best planting density was 300 thousand plants per hectare, with a grain yield of 5176 kg∙hap>−1p>;and the best hybrids were DKS-32 and SYN5515, with grain yields of 5794 and 3791 kg∙hap>−1p>, respectively;likewise, the best dose of fertilizer was between 150 and 200 kg∙hap>−1p> of diammonium phosphate, with a grain yield of 4527 - 4562 kg∙hap>−1p>. In relation to crop rotation, the varieties that stood out for their yield were Huasteca 300 and Vernal, in the case of soybeans;and the hybrids DKS-32 and SYN5515, in sorghum. Soybeans suffered greatly in their early stages of development from the excessive

关键词： Vertisols Tropics Grains Crop Rotations

Numerical Study of Forced Convection Lid-Driven Cavity Flows Using LES （Large Eddy Simulation）

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Journal of Energy and power Engineering 2013年第9期7卷 1669-1680页

作者： Elizaldo D. dos Santos Adriane p. petry Luiz A.O. rocha Francis H.R. Franqa Escola de Engenharia Universidade Federal do Rio Grande Porto Alegre 96201-090 RS Brasil Departamento de Engenharia Mecanica Universidade Federal do Rio Grande do Sul Porto Alegre 90050-I 70 RS Brasil

This study presents the LES （large eddy simulation） of forced convection in laminar and two dimensional turbulent flows when the flow reaches the steady state. The main purpose is the evaluation of a developed numerical methodology for the simulation of forced convection flows at various Reynolds numbers （100 _〈 Rex 〈_ 10,000） and for a fixed prandtl number （pr = 1.0）. The hexahedral eight-node FEM （finite element method） with an explicit Taylor-Galerkin scheme is used to obtain the numerical solutions of the conservation equations of mass, momentum and energy. The Smagorinsky model is employed for the sub-grid treatment. The time-averaged velocity and temperature profiles are compared with results of literature and a CFD （computational fluid dynamics） package based on finite volume method, leading to a highest deviation of nearly 6%. Moreover, characteristics of the forced convection flows are properly obtained, e.g., the effect of the Reynolds number over the multiplicity of scales.

关键词： LES FEM forced convection driven cavity energy equation.

Crohn's disease of esophagus,stomach and duodenum

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World Journal of Gastrointestinal pharmacology and Therapeutics 2019年第2期10卷 35-49页

作者： Andréa Maia pimentel Raquel rocha Genoile Oliveira Santana programa de pós gradua??o em Medicina e Saúde Universidade Federal da Bahia Departamento de Ciências da Nutri??o Universidade Federal da Bahia

Crohn's disease with involvement of the esophagus, stomach and duodenum has a prevalence of 0.5% to 4% in symptomatic adult patients, but some studies have shown that these results may be underestimated, since upper gastrointestinal endoscopy is not performed routinely in the initial evaluation of the disease in adult patients, as it is in the pediatric population. In general, involvement of the upper gastrointestinal tract in Crohn's disease occurs concomitantly with involvement of the lower gastrointestinal tract. The diagnosis depends on clinical,endoscopic, histological and radiological evaluation. The presence of aphthoid ulcers, longitudinal ulcers, bamboo-joint-like appearance, stenoses and fistulas are endoscopic findings suggestive of the disease, and it is important to exclude the presence of Helicobacter pylori infection. The primary histological findings,which facilitate the diagnosis, are the presence of a chronic inflammatory process with a predominance of lymphoplasmacytic cells and active focal gastritis. The presence of epithelioid granuloma, although less frequent, is highly suggestive of the disease in the absence of chronic granulomatous disease. Treatment should include the use of proton pump inhibitors associated with corticosteroids,immunomodulators and biological therapy according to the severity of the disease.

关键词： Crohn’s disease Upper gastrointestinal tract Upper digestive endoscopy Esophagus Stomach Duodenum Chronic gastritis Focal gastritis Epithelioid granuloma

Evaluation of Environmental and Ecological Effects Due to the Accident in an Oil pipe from petrobras in Guanabara Bay,RJ,Brazil

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Open Journal of Marine Science 2014年第4期4卷 298-315页

作者： patrícia p.B.Eichler Beatriz Beck Eichler Felipe Mendonca pimenta Evelyn da rocha Mendes pereira Helenice Vital programa de pos Graduacao em Geofisica e Geodinamica(ppGG) Laboratorio de Geologia e Geofisica Marinha e Monitoramento AmbientalCentro de Ciencias Exatas e da Terra da Universidade Federal do Rio Grande do Norte(GGEMMACCETUFRNBrazil)NatalBrazil Instituto Oceanografico Universidade de Sao Paulo(USP)Sao PauloBrazil Centro de Filosofia e Ciencias Humanas Universidade Federal de Santa CatarinaFlorianopolisBrazil

We aim to evaluate the quality of the Guanabara Bay sediments and the ecological changes due to the pETROBRAS crude oil leak in January 2000. Twenty-six sediment samples collected in July 2000 and in February 2001 were analyzed for pH, dissolved oxygen, and foraminiferal composition. In the northwest and central parts of the bay, low oxygen dissolved values are related to waste discharges with the dominance of Buliminella elegantissima. In winter, near Iguaçu River, the pH of the sediment is low, therefore highly acidic. The acidity is responsible for the foraminiferal low diversity limiting the occurrence of species with fragile tests. On the other hand, thicker tests of Elphidium spp. disappeared last, therefore increasing its relative dominance in winter. In summer, this is a barren zone. The explanation lies in the continuous dissolution of tests that culminated with the total disappearance of these microorganisms one year after the accident.

关键词： Foraminifera pH Oxygen Concentration Guanabara Bay Environmental Quality