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Journal of Minerals and Materials Characterization and Engineering 2014年第2期2卷 135-143页

作者： Maria-Ondina Figueiredo Teresa pereira da Silva Joao pedro Veiga Daniel de Oliveira Maria Joao Batista CENIMAT/I3N Faculty of Sciences and TechnologyNew University of LisbonCampus da CaparicaLisbonPortugal Unit of Mineral Resources and Geophysics National Laboratory for Energy and GeologyAmadoraPortugal

Rhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on ex- ploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of Sao Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.

关键词： Mine Waste Materials By-Products Iberian Pyrite Belt Rhenium XANES Re L_(3)-Edge

Percutaneous decannulation of extracorporeal membrane oxygenation using MANTA device:A real-world single-center experience

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World Journal of Cardiology 2024年第10期16卷 574-579页

作者： Ioannis Milioglou Alice Qian pedro Rafael Vieira de Oliveira Salerno Gabriel Tensol Rodrigues pereira Luis Augusto Palma Dallan Kelsey E Gray Michael Morrison Yasir Abu-Omar Mohammad Eldiasty Cristian Baeza Department of Cardiology University Hospitals Cleveland Medical CenterClevelandOH 44106United States Department of Surgery University Hospitals Cleveland Medical Center and Case Western Reserve University School of MedicineClevelandOH 44106United States

BACKGROUND The MANTA vascular closure device(VCD)represents a novel approach to achieving hemostasis after large-bore femoral access *** clinical studies have evaluated the efficacy of the MANTA device across a range of patient populations undergoing different ***,there is still a paucity of data available concerning the use of MANTA devices in aiding the decannulation of venoarterial extracorporeal membrane oxygenation(VAECMO).AIM To present our single-center experience of utilizing the MANTA VCD in patients undergoing this *** This single-center study included all patients undergoing percutaneous decannulation of femoral VA-ECMO using the MANTA plug-based VCD between January 2021 and October 2023 at University Hospitals Cleveland Medical *** criteria were adult patients who required prolonged(>24 hours)hemodynamic support with *** included all-cause mortality,hemostasis,bleeding,limb ischemia,and site *** This is a retrospective cohort study of 19 patients with a mean age of 56.8 *** of them were males with a mean body mass index of *** most common extracorporeal membrane oxygenation indication was acute coronary syndrome complicated by cardiogenic shock at 36.8%.The mean length of intensive care unit stay for these patients was 18.8±8.42 *** out of 19 patients survived to *** MANTA device was successfully deployed in 19 patients,with 10 procedures conducted at the bedside and 9 in an operating room *** hemostasis was achieved within 5 minutes of MANTA deployment in 17 out of 19 *** 2 patients manual compression after Manta deployment was required to achieve adequate ***,acute lower extremity ischemia was noted in two patients,necessitating endovascular *** infections were reported at the site of MANTA *** Overall,based on our experience and that of other centers,the MANTA VCD

关键词： Extracorporeal membrane oxygenation MANTA Decannulation Hemostasis Ischemia

Growth inhibitory effects of Phyllanthus niruri extracts in combination with cisplatin on cancer cell lines

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World Journal of Gastroenterology 2012年第31期18卷 4162-4168页

作者： Raimundo Fernandes de Araújo Júnior Luiz Alberto Lira Soares Cínthia Raquel da Costa Porto Ranniere Gurgel Furtado de Aquino Hugo Gon alo Guedes pedro Ros Petrovick Tatiane pereira de Souza Aurigena Antunes de Araújo Gerlane Coelho Bernardo Guerra Department of Morphology/Postgraduate Program in Morphological Sciences Federal University of Rio Grande do NorteNatal 59072-970Rio Grande do NorteBrazil Postgraduate Program in Pharmaceutical Sciences Federal University of PernambucoRecife 50670-901PernambucoBrazil Postgraduate Program in Pharmaceutical Sciences Federal University of Rio Grande do NorteNatal 59012-570Rio Grande do NorteBrazil Department of Production and control of drugs Federal University of Rio Grande do SulPorto Alegre 90610-000Rio Grande do SulBrazil Department of Food and Drug Administration Federal University of AmazonasManaus 69077-000AmazonasBrazil Department of Biophysics and Pharmacology Federal University of Rio Grande do NorteNatal 59072-970Rio Grande do NorteBrazil

AIM：To investigate the cytotoxic effects of spray-dried extracts of Phyllanthus niruri in combination with cis- platin on two cancer cell lines. METHODS： Colorectal carcinoma （HT29） and human hepatocellular carcinoma （HepG2） cells were treated with spray-dried extracts of Phyllanthus niruri （SDEPN） either alone or in combination with cisplatin at differ- ent concentrations （0.5 mg/mL and 1 mg/mL） for 4 h and 24 h. To verify and quantify cancer cells treated with these products as well as identify the cell cycle stage and cell viability, we stained the cells with prop- idium iodide and assessed them by flow cytometry. The percentage of cells in different cell cycle phases was quantified and data were expressed as histo- grams. Significant differences between groups were determined using analysis of variance and Bonferroni＇s test, as indicated. A value of P 〈 0.05 was considered to be statistically significant. RESULTS： SDEPN had significantly different cyto- toxic effects on HT29 （2.81 4- 0.11 vs 3.51 4- 1.13, P 〉 0.05） and HepG2 （5.07± 0.3 vs 15.9 ± 1.04, P 〈 0.001） cells when compared to control cells for 4 h. SDEPN also had significantly different cytotoxic effects on HT29 （1.91 ± 0.57 vs 4.53± 1.22, P 〉 0.05） and HepG2 （14.56 ± 1.6 vs 35.67 ± 3.94, P 〈 0.001） cells when compared to control cells for 24 h. Both cell lines were killed by cisplatin in a dose-dependent manner compared to control cells （HepG2 cells for 4 h： 10.78 ± 1.58 vs 53.89 ± 1.53, P 〈 0.001; 24 h： 8.9 ± 1.43 vs 62.78 ± 1.87, P 〈 0.001 and HT29 cells for 4 h： 9.52 ±0.913 vs 49.86 ± 2.89, P 〈 0.001; 24 h： 11.78 ± 1.05 vs 53.34 ± 2.65, P 〈 0.001）. In HT29 cells, pretreat- ment with SDEPN and subsequent treatment with cis-platin resulted in a greater number of cells being killed （12.78 ± 1.01 vs 93.76 ± 1.6, P 〈 0.001）. HepG2 cells showed significant cell killing with treatment with SDEPN when combined with cisplatin （12.87 ± 2.78 vs 78.8 ± 3.02, P 〈 0.001）. CONCLUSION： SDEPN is selectively toxic ag

关键词： Cisplatin Colorectal cancer Liver cancer Phyllanthus n/ruri Cytotoxic effect

Diffusion models for the description of seedless grape drying using analytical and numerical solutions

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Agricultural Sciences 2012年第4期3卷 545-556页

作者： Wilton pereira da Silva Cleide Maria Diniz pereira da Silva e Silva Jürgen Wolfgang Precker Josivanda Palmeira Gomes pedro Luiz Nascimento Laerson Duarte da Silva Federal University of Campina Grande Campina Grande PB Brazil

This article compares diffusion models used to describe seedless grape drying at low temperature. The models were analyzed, assuming the following characteristics of the drying process: boundary conditions of the first and the third kind;constant and variable volume, V;constant and variable effective mass diffusivity, D;constant convective mass transfer coefficient, h. Solutions of the diffusion equation (analytical and numerical) were used to determine D and h for experimental data of seedless grape drying. Comparison of simulations of drying kinetics indicates that the best model should consider: 1) shrinkage;2) convective boundary condition;3) variable effective mass diffusivity. For the analyzed experimental dataset, the best function to represent the effective mass diffusivity is a hyperbolic cosine. In this case, the statistical indicators of the simulation can be considered excellent (the determination coefficient is R2 = 0.9999 and the chi-square is χ2 = 3.241 × 10–4).

关键词： Optimization Convective Boundary Condition Diffusion Model Finite Volume Method

Lead and Cadmium Distribution in Tubes of Galvanized Steel by Hot-Dip Used for Drinking Water Supply

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Journal of Civil Engineering and Architecture 2020年第5期14卷 271-279页

作者： Fernando Benedicto Mainier Felipe Silva Semaan Thais pereira Sarmento pedro Henrique Oliveira Amorim Rodolfo Gomes Shamádos Santos Escola de Engenharia Universidade Federal FluminenseNiteróiRio de Janeiro 27255-125Brazil Instituto de Química Universidade Federal FluminenseNiteróiRio de Janeiro 27255-125Brazil

The main objective of this work was to evaluate the presence of lead and cadmium in galvanized steel tubes by hot-dip used exclusively for drinking water *** this research,samples of galvanized tubes were removed from walls of residential buildings with 30 years of *** the process of hot galvanizing,the manufacturing standards allow or for low cost conveniences,and the use of primary zinc ingot with 1.6%metallic impurities,such as lead and cadmium,is allowed,enabling the incorporation of these metals into the zinc coating deposited on the carbon *** associated corrosion of these tubes can release these toxic metals,contaminating the drinking water used by *** samples taken from the tubes were evaluated by a square-wave anodic stripping voltammetry technique,and the results for lead and cadmium suggested randomly distributed levels,indicating that the contents of these contaminants depend mainly on the quality of the added primary zinc and the operational conditions of the immersion *** metallographic evaluations performed on the samples of the galvanized tubes showed irregularities in thickness and even a lack of the zinc layer deposited on the carbon steel *** facts suggest that galvanized tubes should not be used for drinking water.

关键词： Lead zinc hot-dip galvanized steel square-wave anodic stripping voltammetry contamination

Unprecedented Low-Cost Hybrid Material for CO2 and CH4 Separation

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Journal of Chemistry and Chemical Engineering 2015年第5期9卷 318-323页

作者： Murilo pereira Moises Joziane Gimenes Meneguin Cleiser Thiago pereira da Silva Vicente Lira Kupfer pedro Augusto Arroyo Andrelson Wellington Rinaldi Emerson Marcelo Girotto Silvia Luciana Favaro Eduardo Radovanovic Department of Chemical State University of Maring6 Maringa 87020-900 Brazil Department of Chemical Engineering State University of Maringa Maring6 87020-900 Brazil Department of Mechanical Engineering State University of Maringa Maring6 87020-900 Brazil Federal University Technological of Parana Apucarana 86812-460 Brazil

The zeolite synthesis using waste as silicon source is a promising low-cost process. Sugarcane bagasse ash is a hazardous solid waste generated in large amounts in the sugar industry. Thus, development of new procedures for its productive reuse is relevant. Therefore, this waste was used to prepare a new ZCNT （zeolite/carbon nanotube material）. In this work, ZCNT was applied in a CO2/CH4 separation. The adsorption took place at 303 K under pressure of 0.1 until 20 bar and the data were fitted by Langmuir, Toth and Freundlich equations. The adsorbed amount at 20 bar found was 4.7 mmol of CO2/g and 4.1 mmol of CH4/g; at 3 bar the adsorbed amount was 4.1 mmol of COJg and 1.2 mmol of CHa/g. This result indicates that ZCNT has potential application in COJCH4 separation at low pressures.

关键词： Gas adsorption biogas purification porous materials.

HS-SPME/GC-MS Analysis of VOC and Multivariate Techniques Applied to the Discrimination of Brazilian Varieties of Mango

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American Journal of Analytical Chemistry 2014年第3期5卷 157-164页

作者： Clícia Maria de Jesus Benevides Marcos de Almeida Bezerra pedro Afonso P. pereira Jailson Bittencourt de Andrade Departamento de Ciências da Vida Universidade do Estado da Bahia (UNEB) Salvador Brazil Instituto de Química Universidade Federal da Bahia (UFBA) Salvador Brazil Laboratório de Química Analítica Universidade Estadual do Sudoeste da Bahia (UESC) Jequié Brazil

The present study analyzed the volatile compounds of three mango varieties (Tommy Atkins, Rosa and Espada) using the static headspace technique with SPME coupled to CG-MS. Multivariate methodologies, such as factorial design and response surface methodology, were used to optimize the conditions of adsorption and desorption of these substances. The data were evaluated by using principal components analysis (PCA) and hierarchical grouping analysis, in order to visualize grouping tendencies of volatile compounds. Thirty-seven volatile compounds belonging to different chemical classes, such as esters, terpenes, alcohols and others, were tentatively identified in the three varieties of mango. Amongst them, twenty-three presented chromatographic peaks with relative areas larger than 2%. The multivariate analysis made it possible to visualize the grouping tendencies of the mango samples, according to the presence of their respective volatile substances, and enabled the identification of the groups of substances responsible for the discrimination among the three varieties.

关键词： Mango Volatiles Multivariate Techniques HS-SPME/GC-MS Chemometrics

Molybdenite as a Rhenium Carrier:First Results of a Spectroscopic Approach Using Synchrotron Radiation

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Journal of Minerals and Materials Characterization and Engineering 2013年第5期1卷 207-211页

作者： Teresa pereira da Silva Maria-Ondina Figueiredo Daniel de Oliveira João pedro Veiga Maria João Batista Unit of Mineral Resources and Geophysics National Laboratory for Energy and GeologyAmadoraPortugal Faculty of Sciences and Technology Campus da CaparicaNew University of LisbonLisbonPortugal

The chemical and physical properties of rhenium render it a highly demanded metal for advanced applications in important industrial fields. This very scarce element occurs mainly in ores of porphyry copper-molybdenum deposits associated with the mineral molybdenite, MoS2, but it has also been found in granite pegmatites and quartz veins as well as in volcanic gases. Molybdenite is a typical polytype mineral which crystal structure is based on the stacking of [S-Mo-S] with molybdenum in prismatic coordination by sulphide anions;however, it is not yet clearly established if rhenium ions replace Mo4+ cations in a disordered way or else, if such replacement gives rise to dispersed nanodomains of a rhenium-rich phase. As a contribution to clarify this question, an X-ray absorption spectroscopy (XANES) study using synchrotron radiation was performed at the Re L3-edge of rhenium-containing molybdenite samples. Obtained results are described and discussed supporting the generally accepted structural perspective that rhenium is mainly carried by molybdenite through the isomorphous replacement of Mo, rather than by the formation of dispersed Re-specific nanophase(s).

关键词： Molybdenite Polytypes Rhenium Re L_(3)Absorption Edge XANES

Assessment of Short-term Acupuncture Effect Through Electro-conductivity Variation of Yuan-Source Acupoints

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World Journal of Traditional Chinese Medicine 2015年第4期1卷 48-52页

作者： Daniel Cerqueira Ribeiro André António Moura dos Santos Rui pedro Loureiro Rui Miguel Gonalves Jorge pereira Machado Institute of Biomedical Sciences Abel Salazar-University of Porto (ICBAS-UP) Center for Research on Natural Medicine (CIMN)

Objective: To demonstrate that acupuncture has an instant effect in equilibrating the imbalanced electrical conductivity of Yuan-Source acupoints after intervention on the Luo-Connecting acupoint(one-side) of the same ***: The experiment was designed as a randomized blinded control trial, with 56 volunteers. Reactive Electrical Permeable Points(REPP-mostly Yuan points) were measured in terms of electrical conductivity. Patients with a split-meridian(difference between left and right measurement) were randomly included in the control or experimental group. After five minutes of needle insertion in a Luo acupoint, the needle was removed and REPP were re-measured twice within a five minutes ***: From the 56 volunteers, 32 had a valid Split-Meridian Difference(SMD > 20 μA) and were included in the study. The results indicate that after the third measurement(15 minutes-M3), 100% of the experimental group had SMD 20 μA, at M3, when compared with the initial measurement(M1). Results obtained between the experimental and control group are significantly different(p< 0.001).Conclusions: The present exploratory work indicates that there is evidence of instant body response to acupuncture that can be detected by changes in the electro-conductivity of specific acupoints.

关键词： SMD Source

Biometry and Water Consumption of Sunflower as Affected by NPK Fertilizer and Available Soil Water Content under Semiarid Brazilian Conditions

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Agricultural Sciences 2014年第8期5卷 668-676页

作者： Lúcia Helena Garófalo Chaves Hugo Orlando Carvallo Guerra Vinícius Batista Campos Walter Esfrain pereira pedro Henrique Pinto Ribeiro Departament of Fundamentals and Social Sciences Federal University of Paraíba Campus II Areia Brazil Department of Agricultural Engineering Federal University of Campina Grande (DEAG/UFCG) Campina Grande Brazil Federal Institute of Education Science and Tecnology of the Amapá Campus Laranjal do Jari Av Tancredo Neves Brazil

The present study evaluated the effect of NPK fertilization and available soil water levels on the biometric response and water use of sunflower cv. Embrapa 122-V2000. The experiment was conducted at the Agricultural Engineering Department of the Federal University of Campina Grande, Paraiba State, Brazil, during 2009 and 2010, in a semi-controlled greenhouse using the Eutrofic Regosol. The treatments were defined according to a Baconian matrix, with eleven doses of the nitrogen, phosphorus and potassium and four available soil water levels. The experiment was arranged in a complete randomized design, with three replicates, in a total of 132 sample units. No effect of N and K was observed on plant height. However, it increased significantly with P levels. The stem diameter and the leaf area were affected by the N and K and not by the P. The number of leaves increased significantly with the amount of N, P and K fertilizer. Available soil water content increased significantly in all the variables studied. The best sunflower performance and water consumption were obtained with the 100:120:120 kg·ha-1 NPK and 100% of the available soil water content treatment.

关键词： Helianthus annuus L. Mineral Nutrition Water Management