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Effects of the support material addition on the hydrodynamic behavior of an anaerobic expanded granular sludge bed reactor

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Journal of Environmental Sciences 2017年第4期29卷 224-230页

作者： Tania Pérez-Pérez Gleyce Teixeira correia Wu Hong Kwong Ileana Pereda-Reyes Deny Oliva-Merencio Marcelo Zaiat Institute of Animal Science San Jose de las Lajas Mayabeque Cuba Department of Chemical Engineering Federal University of Sao Carlos Brazil Process Engineering Centre Instituto Superior Politecnico Jose Antonio Echeverria (Cujae) 11901 114 Street Marianao Havana Cuba Study Centre of Renevaable Energy Technologies Instituto Superior Politecnico rose Antonio Echeverria (Cujae) 11901 114 Street Marianao Havana Cuba Biological Processes Laboratory Center for Research Development and Innovation in Environmental Engineering Sao Carlos School of Engineering University of Sao Paulo Engenharia Ambiental - Bloco 4-F Av. Joao Dagnone 17.00 - Santa Angelina 13.563-120 Sao Carlos SP Brazil

As a support material, zeolite can be used to promote the granulation process due to its high settable property and the ability to retain biomass on its surface. The present paper reports on the influence of zeolite addition on the hydrodynamic behavior of an expanded granular sludge bed reactor（EGSB）. Different models were applied to fit the flow pattern and to compare EGSB hydrodynamic performance with and without the addition of zeolite. The experimental data fit the tanks in a series model for zeolite bed height of 5 cm and upflow velocity of 6 m/*** axial dispersion degree（D/uL） was obtained at lower heights of zeolite. The real hydraulic retention time（HRTr） was increased with both increased zeolite bed height and increased upflow velocity. The short-circuit results for 5 cm of zeolite bed and 6, 8 and 10 m/hr upflow velocity were 0.3, 0.24 and 0.19 respectively, demonstrating the feasibility of using zeolite for a proper hydrodynamic environment to operate the EGSB reactor. The presence of zeolite resulted in the higher percentage values of dead zones, ranging from 12% to 24%.Zeolite addition exerted a positive effect on the hydrodynamics pattern for this technology being advantageous for the anaerobic process because of its possible contribution to better biofilm agglomeration, granule formation and substrate-microorganism contact.

关键词： Anaerobic digestion Axial dispersion degree EGSB reactor Hydrodynamics Upflow velocity Zeolite

Promoter hypermethylation of CDH1, FHIT, MTAP and PLAGL1 in gastric adenocarcinoma in individuals from Northern Brazil

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World Journal of Gastroenterology 2007年第18期13卷 2568-2574页

作者： Mariana Ferreira Leal Eleonidas Moura Lima Patrícia Natália Oliveira Silva Paulo Pimentel Assumpo Danielle Queiroz Calcagno Spencer Luiz Marques Payo Rommel Rodríguez Burbano Marília de Arruda Cardoso Smith Genetics Division Department of Morphology Federal University of So Paulo So Paulo SP Brazil Department of Biology Campus Ministro Reis Velloso/Parnába Federal University of Piauí PI Brazil Joo de Barros Barreto University Hospital Federal University of Pará Belém PA Brazil Human Cytogenetics and Toxicological Genetics Laboratory Department of Biology Center of Biological Sciences Federal University of Pará Belém PA Brazil Genetics and Molecular Biology Hemocenter Faculty of Medicine of Marília Marília SP Brazil

AIM：To evaluate the methylation status of CDH1, FHIT, MTAP and PLAGL1 promoters and the association of these findings with clinico-pathological characteristics.METHODS： Methylation-specific PCR （MSP） assay was performed in 13 nonneoplastic gastric adenocarcinorna, 30 intestinal-type gastric adenocarcinorna and 35 diffuse-type gastric adenocarcinorna samples from individuals in Northern Brazil. Statistical analyses were performed using the chi-square or Fisher＇s exact test to assess associations between rnethylation status and clinico-pathological characteristics.RESULTS： Hypermethylation frequencies of CDH1, FHIT, MTAPand PLAGL1 promoter were 98.7%, 53.9%, 23.1% and 29.5%, respectively. Hyperrnethylation of three or four genes revealed a significant association with diffuse-type gastric cancer compared with nonneoplastic cancer. A higher hyperrnethylation frequency was significantly associated with H pylori infection in gastric cancers, especially with diffuse-type. Cancer samples without lymph node metastasis showed a higher FHIT hypermethylation frequency. MTAP hypermethylation was associated with H pylori in gastric cancer samples, as well as with diffuse-type compared with intestinal-type. In diffuse-type, MTAP hypermethylation was associated with female gender.CONCLUSION： Our findings show differential gene methylation in tumoral tissue, which allows us to conclude that hypermethylation is associated with gastric carcinogenesis. MTAP promoter hypermethylation can be characterized as a marker of diffuse-type gastric cancer, especially in women and may help in diagnosis, prognosis and therapies. The H pylori infectious agent was present in 44.9% of the samples. This infection may be correlated with the carcinogenic process through the gene promoter hypermethylation, especially the MTAP promoter in diffuse-type. A higher H pylori infection in diffuse-type may be due to greater genetic predisposition.

关键词： Gastric adenocarcinoma DNA hypermethylation CDH1 FHIT MTAP PLAGL1

Heat Transfer in Steelmaking Ladle

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Journal of Iron and Steel Research International 2008年第3期15卷 11-14,60页

作者： André Zimmer lvaro Niedersberg correia Lima Rafael Mello Trommer Saulo Roca Bragana Carlos Pérez Bergmann Materials Ceramics Lab Federal University of Rio Grande do Sul Porto Alegre 90035-190 Brazil

The heat transfer in a steelmaking ladle was studied. The evaluation of heat transfer of the steel was performed by measuring steel temperature in points including all refining steel process. In the ladle, the temperatures in the refractories and the shell were also measured. To evaluate the thermal profile between the hot and cold faces of the ladle in the slag line position, an experiment which shows the importance of thermal contact resistance was carried out. Higher heat losses in the tapping and the vacuum were verified. The temperature measurements of the ladle indicate distinct thermal profiles in each stage of steel refining. Moreover, as each stage of the process depends on the previous one, the complexity of the ladle thermal control is incremental. So a complete model of heat losses in the ladle is complex.

关键词： heat transfer steelmaking ladle refractory mild steel

Efficient CO_2 Electrolysis with Fluorite Structure Nanoparticles Modified Perovskite Structure La_(0.75)Sr_(0.25)Cr_(0.5)Mn_(0.5)O_(3-δ) Cathode

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Chinese Journal of Structural Chemistry 2018年第10期37卷 1596-1602页

作者： WANG Wen-Yuan HOU Shi-Sheng HU Xiu-lia XIE Kui CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China

Perovskite structure La_（0.75）Sr_（0.25）Cr_（0.5）Mn_（0.5）O_（3-δ）（LSCM） cathode with unique structure can electrolyze CO_2 to CO in solid oxide electrolysers（SOEs）.However,the cell performance is restricted by its electro-catalysis *** this work,fluorite structure nanoparticles（CeO_（2-δ）） are impregnated on LSCM cathode to improve the electro-catalysis activity.X-ray diffraction（XRD）,scanning electron microscope（SEM） and X-ray photoelectron spectroscopy（XPS） together approve that the fluorite structure nanoparticles are uniformly distributed on the perovskite structure LSCM *** measurements illustrate that direct CO_2 electrolysis with 10%mol CeO_（2-δ） impregnated LSCM cathode exhibits excellent performance for current density（0.5 A×cm^（-2）） and current efficiency（～95%） at 800 ℃ under 1.6 *** is believed that the enhanced performance of directed CO_2 electrolysis may be due to the synergetic effect of fluorite structure CeO_（2-δ） nanoparticles and perovskite structure LSCM ceramic electrode.

关键词： perovskite structure fluorite structure LSCM solid oxide electrolysers impregnation

Leadership and organizational innovation in the third sector:A systematic literature review

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International Journal of Innovation Studies 2020年第2期4卷 51-67页

作者： Francisco José Nave do Adro João Carlos correia Leitão Department of Management and Economics University of Beira InteriorNECE-Research Center in Business SciencesEstrada do SineiroCovilhã6200-209Portugal

The impact of the global recession has served to increase pressure on non-profit organizations *** leadership is an essential component of the success of these *** two-fold purpose of this article is to provide a state-of-the-art overview about the existing literature on leadership and organizational innovation in the third sector,as well as to identify research gaps leading to a research model,which can be used in further empirical *** this,we used the collection of existing literature in the Web of *** 144 articles selected in the database were analysed using the VOS-viewer *** show a concern with the renewal of management bodies and a lack of qualified *** study contributes to the construction of an action agenda leading to the establishment of new leadership and organizational innovation model for the third sector.

关键词： Leadership Organizational innovation Third sector Non-profit organizations

Architecting Fault Tolerance with Exception Handling: Verification and Validation

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Journal of Computer Science & Technology 2009年第2期24卷 212-237页

作者： Patrick H. S. Brito Rogério de Lemos Cecília M. F. Rubira Eliane Martins Institute of Computing State University of Campinas Brazil Computing Laboratory University of Kent U.K.

When building dependable systems by integrating untrusted software components that were not originally designed to interact with each other, it is likely the occurrence of architectural mismatches related to assumptions in their failure behaviour. These mismatches, if not prevented during system design, have to be tolerated during runtime. This paper presents an architectural abstraction based on exception handling for structuring fault-tolerant software systems. This abstraction comprises several components and connectors that promote an existing untrusted software element into an idealised fault-tolerant architectural element. Moreover, it is considered in the context of a rigorous software development approach based on formal methods for representing the structure and behaviour of the software architecture. The proposed approach relies on a formal specification and verification for analysing exception propagation, and verifying important dependability properties, such as deadlock freedom, and scenarios of architectural reconfiguration. The formal models are automatically generated using model transformation from UML diagrams： component diagram representing the system structure, and sequence diagrams representing the system behaviour. Finally, the formal models are also used for generating unit and integration test cases that are used for assessing the correctness of the source code. The feasibility of the proposed architectural approach was evaluated on an embedded critical case study.

关键词： exception handling fault-tolerant software architecture model-based test model checking software verification and validation

Kinetic approach to the study of froth flotation applied to a lepidolite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 731-742页

作者： Nathália Vieceli Fernando O.Durao Carlos Guimaraes Carlos A.Nogueira Manuel F.C.Pereira Fernanda Margarido Center for Innovation Technology and Policy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior TecnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laboratorio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 C and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（SE） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the SE function.

关键词： lepidolite lithium ore treatment froth flotation kinetic analysis

SOLUTION CRYSTALLIZATION BEHAVIOR OF LINEAR AND STAR-SHAPED POLY(ETHYLENE GLYCOL)-b-POLY(ε-CAPROLACTONE) BLOCK COPOLYMERS

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Chinese Journal of Polymer Science 2013年第12期31卷 1717-1724页

作者： Ting Yu Jian-qiang Zhang Ya lia Su-dan Shen Wen-feng Wei Peng Chen 王宗宝顾群 Ningbo Institute of Material Technology and Engineering Chinese Academy of Sciences School of Petrochemical Technology Lanzhou University of Technology Institute of Material Engineering Ningbo University of Technology

Lamellar crystals of diblock, triblock and four-arm poly（ethylene glycol）-b-poly（ε-caprolactone）（PEG-b-PCL） crystalline-crystalline copolymers were successfully obtained from their solution. Morphology and structure of lamellar crystals of crystalline-crystalline copotymers were investigated using tapping-mode atomic force microscopy （AFM） and selected area electron diffraction （SAED）. All of these samples showed the truncated-lozenge multilayer basal shapes with central screw dislocation or central stack, which were all obtained simultaneously from the oil bath. The diffraction pattern of PEG block lamellar crystal is attributed to the （120） diffracting planes and the pattern of PCL block lamellar crystal is attributed to the （1 I0） diffracting planes and （200） diffracting planes according to the SAED results. Four （110） crystal growth planes and two （200） crystal growth planes are discovered for the PCL blocks, but the （120） crystal growth planes of PEG blocks are hided in the figure of AFM. The crystalline structure of the four-arm copolymers （FA） is more disorder and confused than that of the diblock （DI） copolymer and the striated fold surface structures of lamellar crystals of four-arm copolymers （FA） are smoother than these of linear analogues, owing to the confused crystallization of blocks caused by the mutual restriction of blocks and the hindrance of the dendritic cores. In addition, the aspect ratio of FA is greater than that of the others. It is hypothesized that there are two reasons for the change of aspect ratios. First, the （200） diffracting planes of PCL crystals grew slowly compared to their （110） diffracting planes because of difference in the energy barrier. Secondly, edge dislocations on the （200） diffracting planes are also responsible for the variation of the aspect ratio. Consequently, the crystalline defects are augmented by the competing blocks crystallized simultaneously and the hindrance of the dendritic cores.

关键词： Lamellar crystal Topological structure PEG-b-PCL Edge dislocation Aspect ratio.

A FUNCTIONAL CONJUGATED HYPERBRANCHED POLYMER DERIVED FROM TETRAPHENYLETHENE AND OXADIAZOLE MOIETIES:SYNTHESIS BY ONE-Pot “A_4+B_2+C_2” POLYMERIZATION AND APPLICAION AS EXPLOSIVE CHEMOSENSOR AND PLED

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Chinese Journal of Polymer Science 2013年第10期31卷 1432-1442页

作者： Wen-bo Wu Shang-hui Ye Li-jin Huang Gui Yu Yun-qi Liu Jin-gui Qin Zhen lia Department of Chemistry Hubei Key Lab on Organic and Polymeric Opto-Electronic MaterialsWuhan University Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences

A new conjugated hyperbranched polymer （hb-TFO） containing tetraphenylethylene （TPE） units, a famous aggregation-induced emission （AIE） active group, as the core, was synthesized successfully with modest yield via one-pot Suzuki polymerization reaction. Thanks to the introduction of TPE moieties, hb-TFO exhibited aggregation-enhanced emission （AEE） property, and could work as explosive chemosensor with high sensitivity. The polymeric light-emitting diode （PLED） device was fabricated to investigate its electroluminescent property, and hb-TFO demonstrated a maximum luminance efficiency of 0.22 cd/A and a maximum brightness of 545 cd/m2 at 15.9 V.

关键词： Hyperbranched polymer AEE TPE Explosive chemosensor PLED.