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Evaluation of Dissolved Organic Carbon Using Synchronized Fluorescence Emission Spectra and Unsupervised Method of Principal Component Analysis (PCA) and Independent Component Analysis (ICA)

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Journal of Water Resource and Protection 2019年第3期11卷 244-279页

作者： Tais Cristina Filippe Luana Mayumi Takahasi Marques Heloise G. Knapik Júlio César Rodrigues de Azevedo jorge costa pereira Department of Chemistry and Biology Federal University of Technology—Paraná Curitiba Brazil Department of Hydraulic and Sanitation Federal University of Technology—Paraná Curitiba Brazil Department of Chemistry University of Coimbra Coimbra Portugal

Dissolved organic matter (DOM) can be originated from autochthonous or allochthonous sources, where allochthonous DOM can be from pedogenic sources (humic substances—HSs) or anthropogenicsources (wastewater). The analysis of fluorescence emission, excitation, synchronous or excitation-emission matrix (EEM) have been used to identify the main source or probable contribution of dissolved compounds, such as humic acids (HA), fulvic acids (FA) and dissolved organic carbon (DOC) from sewage, but does not quantify. Fluorescence emission is a powerful technique to detect and qualify organic dissolved compounds but fails in quantitative aspects. In this work, we propose an in situ method for direct determination of DOC using synchronous fluorescence spectra with independent component analysis (ICA). Well known standard solutions were used for method development and validation. In this work, we show that it is possible to predict the number of independent contributions using an unsupervised method based on iterative Principal Component Analysis and Independent Component Analysis (PCA-ICA) approach over combined matrix results. Within these results it’s also possible to see that with a very small amount of independent components it is possible to describe environmental samples of HA, FA and primary productivity (PP).

关键词： Independent Component Analysis Dissolved Organic Carbon Spectra Deconvolution Synchronized Fluorescence

Late Ordovician cornulitid tubeworms from high-latitude peri-Gondwana(Sardinia and the Pyrenees) and their palaeobiogeographic significance

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Journal of Palaeogeography 2024年第4期13卷 939-953页

作者： Olev Vinn jorge Colmenar Samuel Zamora Sofia pereira Gian Luigi Pillola Abdullah A.Alkahtane Saleh Al Farraj Magdy El Hedeny Institute of Ecology and Earth Sciences University of Tartu Instituto Geológico y Minero de Espa?a-CSIC Centro de Geociências Departamento de Ciências da Terra Universidade de Coimbra Rua Sílvio Lima Dipartimento di Scienze Chimiche e Geologiche Università degli Studi di Cagliari Cittadella Universitaria College of Science King Saud University Geology Department Faculty of Science Alexandria University

Seven Cornulites species, including a new one—Cornulites leonei n. sp., are described from the Upper Ordovician Portixeddu Formation(Katian, stage slices Ka2-3) of Sardinia and the Cavá(lower Katian,stage slice Ka2) and Estana(upper Katian, stage slices Ka3-4) formations of the Pyrenees. The Sardinian and Pyrenean cornulitids represent an adaptation to live in environments with high sedimentation rates and limited hard substrates availability. Their prominent annuli could have had a stabilizing function in the soft sediment that helped cornulitids to keep a favourable position in the sediment to enable suspension feeding. The known Late Ordovician cornulitid diversity in different Gondwana areas is low, usually ranging from one to three taxa, being higher(seven) in Sardinia. Like other benthic groups during the Late Ordovician, the cornulitid tubeworm faunas within the high-latitude peri-Gondwana Province indicate a certain endemism and share morphological and ecological affinities, such as a small body size and tubes with a strikingly small apical angle. Although essentially endemic, some links with cornulitids from the Late Ordovician of Scotland are revealed.

关键词： Tentaculitid tubeworms Cornulites Mediterranean Palaeoecology Katian

香椿的树木年轮宽度与超年生殖行为的相互关系:对树轮学研究的警示

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Journal of Plant Ecology 2024年第1期17卷 165-171页

作者： Monique Silva costa Thaís jorge de Vasconcellos Claudio Sergio Lisi Arno Fritz Neves Brandes Mario Tomazello-Filho Cátia Henriques Callado Instituto de Aplicação Fernando Rodrigues da Silveira Universidade do Estado do Rio de JaneiroRua Barão de Itapagipe96.Rio Comprido 20261-005Rio de JaneiroBrazil Laboratório de Anatomia Vegetal Universidade do Estado do Rio de JaneiroRua São Francisco Xavier524Maracanã20550-013Rio de JaneiroBrazil Departamento de Biologia Universidade Federal de SergipeAv.Marechal Rondon s/n-Rosa Elze.São Cristóvão 49100-000SergipeBrazil Departamento de Biologia Geral Universidade Federal FluminenseRua Prof.Marcos Waldemar de Freitas ReisS/N.Gragoatá24210-201Rio de JaneiroBrazil Escola Superior de Agricultura Luiz de Queiroz Universidade de São PauloAv.Pádua Dias11.Piracicaba 13418-900São PauloBrazil

资源分配到生殖过程涉及到生态和进化因素,可能会减少植物的营养生长。这种相互关系在自然界中不容易观察到,因为有许多参数可以限制生殖结构的产生或生物量的增加。我们将香椿(Cedrela odorata L.,楝科)在里约热内卢州大西洋森林中的... 详细信息

资源分配到生殖过程涉及到生态和进化因素,可能会减少植物的营养生长。这种相互关系在自然界中不容易观察到,因为有许多参数可以限制生殖结构的产生或生物量的增加。我们将香椿(Cedrela odorata L.,楝科)在里约热内卢州大西洋森林中的树木年轮宽度与超年生殖行为相关联。总体而言,生殖结构的发育发生在湿润的年份,在生长季初期没有出现水分亏缺。然而,在这些年份,树木年轮宽度较小。这些结果可能与树木年轮宽度与当地气候之间缺乏相关性有关。因此,我们强调在径向生长研究中纳入生殖数据的重要性,以扩大对热带森林生长变异性的理解。

关键词：植物生长策略树木年轮学树木生态学生殖权衡

Natural Gas Power Plants in the System Security Role—The Situation and Solutions in Brazil

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Energy and Power Engineering 2024年第4期16卷 151-178页

作者： Ciro Galvão Hirdan Katarina de Medeiros costa Eduardo Guedes pereira Edmilson Moutinho dos Santos Dorel Soares Ramos Polytechnic School (EP) University of S&#227o Paulo S&#227o Paulo Brazil Institute of Energy and Environment (IEE) University of S&#227o Paulo S&#227o Paulo Brazil

This study aims to apply a methodology to analyze the regulatory obstacles for the development of thermal power plants in a country. The study uses Brazil as an application case, although mostly of the findings can be useful to other countries. It also discusses other policies and actions by the government that may contribute to the growth of natural gas-fired power plants. Using deductive and comparative research methods, the first part of this method focuses on the stage of thermoelectric power generation in Brazil. The subsequent sections present the role of the integration of gas and electricity sectors, the main obstacles to the expansion of natural-gas power generation, how the country has deal with the expansion of natural-gas power generation, as well as how other obstacles has been faced. In raising the research question, when comparing the research results of selected countries, it should be noticed the impact that the experience and lessons elsewhere have had on policies formulation on Brazil. Our conclusions pointed out that adequate policies for the natural gas-electricity Brazilian market integration make advisable the unification of electricity and natural gas agencies. We recommended developing a mathematical model to support decision-making on natural gas and electricity integration.

关键词： Component Formatting Style Styling Insert

弱局限沉积环境下碳酸盐岩特征及有利储层成因——以中阿拉伯盆地A油田下白垩统Yamama组为例

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石油勘探与开发 2024年

作者：万洋李峰峰任立新郭睿徐宁 Michael Poppelreiter jorge costa Gomes 李蕾中国石油勘探开发研究院中国石油迪拜研究院

基于岩心、铸体薄片、物性、CT扫描、测井、测试及地震等资料，以中阿拉伯盆地A油田下白垩统Yamama组为例，以揭示弱局限沉积环境下碳酸盐岩储层特征及有利储层成因机理。研究表明：弱局限沉积环境主要为潟湖沉积，储层以粒泥灰岩、泥... 详细信息

基于岩心、铸体薄片、物性、CT扫描、测井、测试及地震等资料，以中阿拉伯盆地A油田下白垩统Yamama组为例，以揭示弱局限沉积环境下碳酸盐岩储层特征及有利储层成因机理。研究表明：弱局限沉积环境主要为潟湖沉积，储层以粒泥灰岩、泥粒灰岩和粘结岩为主，岩性序列横向变化快，可对比性差；发育孔隙型储层，储集空间以微孔、铸模孔和生物体腔孔为主，原生粒间孔发育程度总体较低，孔喉以中喉和微喉为主；物性主要为中低孔、低渗和特低渗，不同渗透性的储层垂向上呈薄互层状展布，中高渗储层发育程度低且分布不稳定。研究认为：弱局限沉积环境主体发育多种低能浅水微相，准同生期成岩作用强烈，沉积-成岩作用耦合控制储层岩石物理特征和非均质性。弱局限沉积环境下，局部富含似球粒的高能颗粒滩，原生粒间孔发育，是有利储层发育的重要沉积相带；良好的水介质条件导致生物多样性，潟湖中的藻类、滩后中的胞网菌分别与铸模孔和生物体腔孔具有良好的相关性，且生屑含量越高，孔隙体积越高；藻类和胞网菌等易溶性生屑被选择性溶蚀，有利于形成大量次生孔隙，可有效改善储层物性。

关键词：中阿拉伯盆地下白垩统 Yamama组弱局限沉积环境潟湖碳酸盐岩有利储层

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco E jorge José R da costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

Novel experimental techniques to assess the time-dependent deformations of geosynthetics under soil confinement

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 410-419页

作者： Carina Maia Lins costa jorge Gabriel Zornberg Department of Civil Engineering Federal University of Rio Grande do NorteAv.Senador Salgado Filho 3000NatalRio Grande do Norte59078-970Brazil Department of Civil Architectural and Environmental Engineering The University of Texas at Austin301 E.Dean KeetonAustinTX78712-0280USA

A new experimental approach to assess the impact of soil confinement on the long-term behavior of geosynthetics is presented in this *** experimental technique described herein includes a novel laboratory apparatus and the use of different types of tests that allow generation of experimental data suitable for evaluation of the time-dependent behavior of geosynthetics under soil *** soil-geosynthetic interaction equipment involves a rigid box capable of accommodating a cubic soil mass under plane strain conditions.A geosynthetic specimen placed horizontally at the mid-height of the soil mass is subjected to sustained vertical pressures that,in turn,induce reinforcement axial loads applied from the soil to the *** previously reported studies on geosynthetic behavior under soil confinement,the equipment was found to be particularly *** minor setup modifications,not only interaction tests but also in-isolation geosynthetic stress relaxation tests and soil-only tests under a constant strain rate can be conducted using the same ***,the time histories of the reinforcement loads and corresponding strains are generated throughout the *** from typical tests conducted using sand and a polypropylene woven geotextile are presented to illustrate the proposed experimental *** testing procedure was found to provide adequate measurements during tests,including good repeatability of test *** soilegeosynthetic interaction tests were found to lead to increasing geotextile strains with time and decreasing reinforcement tension with *** test results highlighted the importance of measuring not only the time history of displacements but also that of reinforcement loads during *** approach of using different types of tests to analyze the soilegeosynthetic interaction behavior is an innovation that provides relevant insight into the impact of soil confinement on the time-dependent deformations of geos

关键词： Geosynthetics Geotextile Creep Stress relaxation Reinforced soil Long-term deformation

Main flexible pavement and mix design methods in Europe and challenges for the development of an European method

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第4期4卷 316-346页

作者： Paulo pereira jorge Pals Centre for Territory Environment and Construction Uniuersity of Minho Guimaraes 4800-058 Portugal

Pavement and mix design represent one of the key components within the life cycle of a road infrastructure, with links to political, economic, technical, societal and environmental issues. Recent researches related to the characteristics of materials and associated behavior models both for materials and pavement, made it appropriate to consider updating current pavement design methods, and especially in the USA this has already been in process while in Europe uses of the methods developed in the early 1970s. Thus, this paper firstly presents a brief historical overview of pavement design methods, high- lighting early limitations of old empirical methods. Afterwards, French, UK and Shell methods currently in use in Europe will be presented, undeHining their main components in terms of methodology, traffic, climatic conditions and subgrade. The asphalt mix design and modeling in Europe are presented with their inclusion in the pavement design methods. Finally, the main challenges for the development of a European pavement design method are presented as well as the recent research developments that can be used for that method.

关键词： Road pavement Pavement design Mix design Future challenges

An illustrated checklist of macrofaunal molluscs from soft-sediments of the Abrolhos Parcel(northeastern,Brazil)with 15 new records

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Journal of Oceanology and Limnology 2021年第2期39卷 671-682页

作者： Flávia Maria pereira da costa Ana Maria Setubal PIRES-VANIN Departamento de Oceanografi a Biológica Instituto Oceanográfi coUniversidade de São PauloSão Paulo 05508-120Brazil

Comprehensive understanding of marine biodiversity is essential for conservation,especially for vulnerable *** this paper,we implemented and illustrated a checklist of molluscs from the Abrolhos Parcel,Brazil,the most important coralline area in South Atlantic *** list features 100 species belonging to 4 classes and 85 genera,of which 15 are new records for Bahia State,northeast *** results highlight the potential for new records in the *** species came from 54 unconsolidated sediment samples collected from the bottom of the reef with a 0.042-m^(2) van Veen *** the listed species,Curveulima sp.,Notarchus *** Guyanella clenchi are new records for the South Atlantic,while Caecum metamorphosicum,Eratoidea janeiroensis,Volvarina serrei,Solemya notialis,Solariorbis shimeri,and Amphithalamus glabrus are endemic to Brazilian waters.A comparison of our results with those obtained in other reef environments indicates that the Abrolhos Parcel has a rich malacofauna and suggests that many more species can still be found with more samplings.

关键词： Bivalvia Gastropoda micromolluscs Scaphopoda Solenogastres southwest Atlantic