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Chinese journal of Catalysis 2019年第6期40卷 940-952页

作者： Huiyan Pan Xiaowei Chen Oihane Sanz Miguel A.Cauquia jose M.Rodriguez-Izquierdoa juan j.delgado Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica y Química Inorgánica Facultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain Applied Chemistry Department University of Basque Country(UPV-EHU)Apdo.1072San Sebastian20080Spain

Cryptomelane has been widely applied as catalyst in oxidation reactions due to its excellent redox properties and low ***,a novel one-pot hydrothermal synthesis using a potassium permanganate aqueous solution as precursor and ethanol as reducing agent has successfully been developed to obtain cryptomelane *** synthetic route makes it possible to control the amount of potassium incorporated into the structure of the cryptomelane by selecting the appropriate synthesis temperature and ethanol initial *** advantage of this approach,the effect of potassium concentration on the structural stability and reducibility of the cryptomelane,which are poorly discussed in the literature,has been *** have observed that samples with low content of potassium(~11%)show high conversions of CO to CO2 especially at low *** lower activity of the samples with high K contents(~16%)can be ascribed to the beneficial effect of K on the structural stability of cryptomelane in detriment of labile oxygen on cryptomelane surface.

关键词： Cryptomelane Pyrolusite Catalytic CO oxidation Hydrothermal synthesis Potassium content

Tax avoidance and earnings management:a neural network approach for the largest European economies

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Financial Innovation 2023年第1期9卷 558-582页

作者： Francisco j.delgado Elena Fernández‑Rodríguez Roberto García‑Fernández Manuel Landajo Antonio Martínez‑Arias Department of Economics Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain Department of Accounting Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain Department of Applied Economics Faculty of Economics and BusinessUniversity of OviedoAvda.del CristoS/N33071 OviedoSpain

In this study,we investigate the relationship between tax avoidance and earnings management in the largest five European Union economies by using artificial neural network *** methodology allows us to deal with nonlinearities detected in the data,which is the principal contribution to the previous *** ana-lyzed Compustat data for Germany,the United Kingdom,France,Italy,and Spain for the 2006–2015 period,focusing on discretionary *** considered three tax avoidance measures,two based on the effective tax rate(ETR)and one on book-tax differences(BTD).Our results indicate the presence of nonlinear patterns and a posi-tive,statistically significant relationship between discretionary accruals and both ETR indicators implying that when companies resort to earnings management,a larger tax-able income—and thus higher ETR and lesser tax avoidance–would ***,as also highlighted by the fact that discretionary accruals do not appear to affect BTD,our evidence does not suggest that companies are exploiting tax manipulation to reduce their tax payments;thus,the gap between accounting and taxation seems largely unaf-fected by earnings management.

关键词： Tax avoidance Earnings management Artificial neural networks European Union

Synthesis of palladium-rhodium bimetallic nanoparticles for formic acid dehydrogenation

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journal of Energy Chemistry 2021年第1期30卷 301-309,I0010页

作者： Ilaria Barlocco Sofia Capelli Elisa Zanella Xiaowei Chen juan jdelgado Alberto Roldan Nikolaos Dimitratos Alberto Villa Dipartimento di Chimica Universitàdegli Studi di MilanoMilan I-20133Italy Departamento de Ciencia de los Materiales Ingeniería Metalúrgica y Química InorgánicaFacultad de CienciasUniversidad de CádizCampus Río San PedroPuerto Real(Cádiz)E-11510Spain School of Chemistry Cardiff UniversityMain BuildingPark PlaceCF103AT CardiffUnited Kingdom Dipartimento di Chimica Industriale e dei Materiali Alma Mater Studiorum Universitàdi BolognaViale Risorgimento 4I-40136 BolognaItaly

Herein,we report for the first time the synthesis of preformed bimetallic Pd-Rh nanoparticles with different Pd:Rh ratios(nominal molar ratio:80-20,60-40,40-60,20-80) and the corresponding Pd and Rh monometallic ones by sol immobilization using polyvinyl alcohol(PVA) as protecting agent and NaBH4 as reducing agent,using carbon nanofibers with high graphitization degree(HHT) as the desired *** synthesized catalysts were characterized by means of Transmission Electron Microscopy(TEM) and inductively coupled plasma optical emission spectroscopy(ICP-OES).TEM shows that the average particle size of the Pd-Rh nanoparticles is the range of 3-4 nm,with the presence of few large agglomerated *** bimetallic catalysts,EDX-STEM analysis of individual nanoparticles demonstrated the presence of random-alloyed nanoparticles even in all cases Rh content is lower than the nominal one(calculated Pd:Rh molar ratio:90-10,69-31,49-51,40-60).The catalytic performance of the Pd-Rh catalysts was evaluated in the liquid phase dehydrogenation of formic acid to *** was found that Pd-Rh molar ratio strongly influences the catalytic ***-rich catalysts were more active than Rh-rich ones,with the highest activity observed for Pd90:Rh10(1792 h^(-1)),whereas Pd69:Rh31(921 h^(-1)) resulted the most stable during recycling ***,Pd90:Rh10 was chosen as a representative sample for the liquid-phase hydrogenation of muconic acid using formic acid as hydrogen donor,showing good yield to adipic acid.

关键词： Palladium Rhodium Alloy Formic acid Hydrogen Muconic acid

2011年5月11日西班牙东南洛尔卡M_W5.1地震诱发的大范围滑坡

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世界地震译丛 2013年第3期44卷 66-80页

作者： P.Alfaro j.delgado F.j.García-Tortosa L.Lenti j.A.López C.López-Casado S.Martino 许冲中国地震局地质研究所

2011年5月11日，一个中等震级地震（Mw5．1）袭击了西班牙东南部洛尔卡城和邻近地区，造成了显著的破坏和人员伤亡。通过地震影响区的野外考察对250多处主要是碎裂型（岩／土崩塌、碎裂的土质滑坡和岩崩）诱发滑坡进行了定点和特征描述... 详细信息

2011年5月11日，一个中等震级地震（Mw5．1）袭击了西班牙东南部洛尔卡城和邻近地区，造成了显著的破坏和人员伤亡。通过地震影响区的野外考察对250多处主要是碎裂型（岩／土崩塌、碎裂的土质滑坡和岩崩）诱发滑坡进行了定点和特征描述。与以前该区域相似震级（Mw4．7～5．0）的地震事件，以及以前预测地震期间斜坡表现的模型结果相比，本次地震诱发滑坡的数量相当大。提出了几个原因来解释这种差异：（1）地震序列中相对高震级（Mw4．5）的前震可能弱化了区域内的斜坡强度；（2）这些事件产生了高的地震动峰值；（3）发生了地形场地效应。本研究的结果指出了在改进区域斜坡特征研究模型时考虑这些影响的重要性。

关键词：地震诱发滑坡滑坡编目浅源地震中等震级地形场地效应洛尔卡

长骨生长端扩散张量成像:膝关节骺板与干骺端柱状结构的试验示范

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国际医学放射学杂志 2015年第1期 67-67页

作者： C.jaimes j.I.Berman j.delgado V.Ho-Fung D.jaramillo Department of Radiology The Children ’s Hospital of Philadelphia

目的证实运用在体骺板扩散张量成像和纤维束成像来检查与生长率、位置和年龄相关变化的可行性。材料与方法本回顾性研究是经过伦理审查委员会批准并符合

关键词：扩散张量纤维束骺板膝关节干骺端

生长板扩散张量成像:一种骨骼生长的可能生物标记——来自151例儿童的经验

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国际医学放射学杂志 2017年第5期 591-591页

作者： M.A.Bedoya j.delgado j.I.Berman N.A.Chauvin D.Zurakowski R.Ramirez-Grueso 李清 Department of Radiology Children’s Hospital of Philadelphia

摘要目的确定股骨远端和胫骨近端扩散张量成像(DTI)和纤维束成像改变与年龄、性别及身高的关系。材料与方法本研究经机构伦理委员会批准并符合HIPAA,无需知

关键词：扩散张量 ADC 纤维束生长板

Simplicial Indicator Kriging

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journal of China University of Geosciences 2008年第1期19卷 65-71页

作者： R Tolosana-delgado V Pawlowsky-Glahn j j Egozcue Department of Sedimentology and Environmental Geology Georg-August-Universitt Gttingen D-37077 Gttingen Germany Department of Computer Science and Applied Mathematics University of Girona Girona Spain Department of Applied Mathematics III Universidad Politécnica de Catalunya Barcelona Spain

Indicator kriging （IK） is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. The result is a discrete approximation, and its corresponding estimated probability density function can be viewed as a composition in the simplex. This fact suggested a compositional approach to IK which, by construction, avoids all its standard drawbacks （negative predictions, not-ordered or larger than one）. Here, a simple algorithm to develop the procedure is presented.

关键词： Aitchison geometry compositional data disjunctive kriging log-ratio approach simplex.

On the Structure of Graded Leibniz Algebras

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Algebra Colloquium 2015年第1期22卷 83-96页

作者： Antonio j. Calderon Martin jose M. Sfinchez delgado Departamento de Matemdticas Universidad de Cadiz 11510 Puerto Real Cadiz Spain

We study the structure of graded Leibniz algebras with arbitrary dimension and over an arbitrary base field K. We show that any of such algebras ￡ with a symmetric G-support is of the form ￡ = U-∑jIj with U a subspace of ￡1, the homogeneous component associated to the unit element 1 in G, and any Ij a well described graded ideal of ￡, satisfying [Ij, Ik]= 0 if j≠ k. In the case of ￡ being of maximal length, we characterize the gr-simplicity of the algebra in terms of connections in the support of the grading.

关键词： graded Leibniz algebra infinite dimensional Leibniz algebra structure theory

Generalized Baumslag-Solitar Graphs with Soluble Fundamental Groups

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Algebra Colloquium 2014年第1期21卷 53-58页

作者： Alberto L. delgado Derek j.S. Robinson Mathew Timm vDepartment of Mathematics illinois State University Normal IL 61790 USA Department of Mathematics University of Illinois at Urbana-Champaign Urbana IL 61801 USA Department of Mathematics Bradley University Peoria IL 61625 USA

It is shown that the generalized Baumslag-Solitar graphs which have soluble fundamental groups can be constructed from four simple types of graph by a process of decoration. The method of proof is elementary and emplo... 详细信息

关键词： generalized Baumslag-Solitar graph soluble fundamental group

Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water

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journal of Environmental Sciences 2019年第2期31卷 403-414页

作者： Cesar Nieto-delgado joel Gutiérrez-Martínez j.Rene Rangel-Méndez Environmental Sciences Division Potosino Institute of Scientific and Technological ResearchIPICyT

The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures.

关键词： Iron oxide nanostructures Hydrothermal synthesis Microwave Adsorption capacity Kinetics