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Potential application of electron work function in analyzing fracture toughness of materials

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Journal of Materials Science & Technology 2017年第10期33卷 1128-1133页

作者： Hao Lu Chenxin Ouyang Xianguo Yan Jian Wang Guomin Hua reinaldo Chung d.Y.Li department of Chemical and Materials Engineering University of Alberta Edmonton. Alberta T6G 1H9 Canada College of Materials Science and Engineering Donghua University Shanghai 201620 China School of Mechanical Engineering Taiyuan University of Science and Technology Taiyuan 030024 China Extraction Reliability Engineering Suncor Energy Inc. Fort McMurray Alberta Canada

Fracture toughness determines materials＇ resistance to fracture, which is measured often using impact or bending tests. However, it is difficult to evaluate fracture toughness of coatings and small *** this article, using white irons as sample materials, we explore a possible approach of using electron work function（EWF） as an indicator in evaluating fracture toughness of hard metallic materials. This parameter is promising for being utilized to analyze toughness of protective coatings and small objects as well as bulk materials. Through comparison with results obtained from impact tests and elastic modulus measurement, effectiveness of this EWF approach is demonstrated.

关键词： Fracture toughness Elastic modulus Electron work function

Online Learning Control for Harmonics Reduction Based on Current Controlled Voltage Source Power Inverters

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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 447-457页

作者： Naresh Malla Ujjwol Tamrakar dipesh Shrestha Zhen Ni reinaldo Tonkoski Electrical Engineering and Computer Science department South Dakota State University IEEE

Nonlinear loads in the power distribution system cause non-sinusoidal currents and voltages with harmonic *** active filters(SAF) with current controlled voltage source inverters(CCVSI) are usually used to obtain balanced and sinusoidal source currents by injecting compensation ***,CCVSI with traditional controllers have a limited transient and steady state *** this paper,we propose an adaptive dynamic programming(AdP) controller with online learning capability to improve transient response and *** proposed controller works alongside existing proportional integral(PI) controllers to efficiently track the reference currents in the d-q *** can generate adaptive control actions to compensate the PI *** proposed system was simulated under different nonlinear(three-phase full wave rectifier) load *** performance of the proposed approach was compared with the traditional *** have also included the simulation results without connecting the traditional PI control based power inverter for reference *** online learning based AdP controller not only reduced average total harmonic distortion by 18.41%,but also outperformed traditional PI controllers during transients.

关键词： Adaptive dynamic programming(AdP) current controlled voltage source power inverter(CCVSI) online learning based controller neural networks shunt active filter(SAF) total harmonic distortion(THd)

Influence of physical-anatomical wood variables on charcoal physical-mechanical properties

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Journal of Forestry Research 2023年第2期34卷 531-538页

作者： Allan Motta Couto Thiago Campos Monteiro Paulo Fernando Trugilho JoséTarcísio Lima Joséreinaldo Moreira da Silva Alfredo Napoli diego Pierre de Almeida department of Forestry Science State University of Mato Grosso do Sul–UEMSAv.Graziela Maciel BarrosoKm 12 Zona RuralAquidauanaMS 79200000Brazil department of Forestry Engineering and Technology Federal University of Paraná–UFPRA V.Pref.Lothário Meissner 632Jardim BotânicoCuritibaPR 80210170Brazil department of Forestry Science Federal UniversityLavras–UFLALavrasMG 37200000Brazil département de Performance des Systèmes de Production Et de Transformation Tropicaux Centre de Coopération Internationale em Recherche Agronomique pour le Développement–CIRADMontpellierFrance

This research assessed the relationship between wood physical-anatomical variables and charcoal physical-mechanical *** trees were harvested and mechanically processed into standard pieces for laboratory *** following variables were determined:wood density,fiber length and width,fiber lumen diameter and wall thickness,fiber wall fraction,and vessel *** charcoal was produced in a laboratory and gravimetric yield,relative density,and mechanical properties ***’s correlation coefficients,multivariate statistical analysis of canonical correlation,and principal component analysis were used to evaluate the relationship between wood and charcoal *** width was not significantly correlated with charcoal *** bulk density,hardness,and strength were positively correlated with wood density,fiber length,wall thickness,and wall *** properties were negatively correlated with fiber lumen diameter and vessel *** results will help identify the best wood with adequate physical-mechanical properties for industrial charcoal proces sing.

关键词： Biomass density Energy Fiber Vessel

Treatment of Materials Contaminated with Polychlorinated Biphenyls(Pcbs):Comparison of Traditional Method and Supercritical Fluid Extraction

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American Journal of Analytical Chemistry 2012年第12期3卷 891-898页

作者： dannielle Jannaine Silva Felipe V.Pietri José Ermirio F.Moraes reinaldo Camino Bazito Camila Gambini Pereira department of Chemical Engineering Federal University of Rio Grande do NorteNatalBrazil department of Chemical Engineering Federal University of Sao PauloSao PauloBrazil department of Chemistry University of Sao PauloSao PauloBrazil

The objective of this study was to develop an experimental methodology for the extraction of polychlorinated biphenyls (PCBs) from contaminated soil and wood material using the Soxhlet extraction method and supercritical fluid technology. The sample PCB contents were quantified using Gas Chromatography-Mass Spectrometry (GC/MS). Conventional extractions of PCBs from soil samples showed higher extraction yields for samples with the highest initial PCB levels and longest extraction times. Specific PCBs yielded 74.0% - 78.3% removal using ethanol as the solvent. 91.0% - 94.3% removal of the total PCB content was achieved using hexane as the solvent. Supercritical fluid extraction of soil samples resulted in 50.0% - 70.5% removal for specific PCBs and 57.3% removal of the total PCB content. For wood, the use of Soxhlet extraction resulted in 87.0% - 94.0% removal for specific PCBs and 95.0% - 96.3% removal of the total PCB content. Supercritical fluid extraction of wood samples resulted in 91.1% - 95.0% removal of specific PCBs and 95.1 % of the total PCB content.

关键词： Polychlorinated Biphenyls Extraction Soil Wood

Correlation between Solar Semi-diameter and Geomagnetic Time Series

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International Journal of Geosciences 2012年第2期3卷 321-328页

作者： Eugênio Reis Neto Vitor Hugo Alves dias Andrés reinaldo Rodriguez Papa Alexandre Humberto Andrei Jucira Lousada Penna Irineu Figueiredo Sérgio Calderari Boscardin Victor de Amorin d’ávila Observatório Nacional Rio de Janeiro Brazil

We study the correlation between geomagnetic and solar semi-diameter measurements made at two of our ground stations (Vassouras and Rio de Janeiro, Brazil). The study comprises the period from March 1998 to November 2003, for which daily means were compared. Both series describe correlated, but different, phenomena and, consequently, before a correlation study, an individual analysis of each data set was necessary. One of the motivations of the present work was to further explore the correlation with lags found between the solar semi-diameter and some solar activity estimators, which supports the probabilistic forecasting of the solar activity and hence, of the solar driven geomagnetic variations.

关键词： Solar diameter Geomagnetic Series Correlation Time Series

Reappraisal of Hepatocellular Adenoma from Federal Health System, Rio de Janeiro, Brazil

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Open Journal of Organ Transplant Surgery 2019年第1期9卷 1-10页

作者： reinaldo Fernandes Klaus Steinbruck danielle B. delai Jú lia R. N. Souza Igor duque daniel Barbosa Marcelo Enne Renato Cano Marcelo d’Oliveira Luiza Maciel Giuliano Bento Hepatobiliary Surgery Bonsucesso Federal Hospital Health Ministry Rio de Janeiro Brazil Surgery department Antonio Pedro University Hospital Fluminense Federal University Niter&oacute i Brazil Hepatobiliary Surgery Bonsucesso Federal Hospital Health Ministry Rio de Janeiro Brazil Antonio Pedro University Hospital Fluminense Federal University Niter&oacute i Brazil Hepatobiliary Surgery Servidores do Estado Federal Hospital Health Ministry Rio de Janeiro Brazil Hepatobiliary Surgery Ipanema Federal Hospital Health Ministry Rio de Janeiro Brazil Nacional Cancer Institute Rio de Janeiro Brazil

Background: Hepatocellular adenoma is a rare liver tumor that may require surgical treatment in cases of hemorrhage or suspicion of malignant lesions. Aim: To analyze data from patients who underwent hepatectomy for hepatocellular adenoma (HCA) in Rio de Janeiro, Brazil. Methods: From January 2005 to March 2019, sixty-nine patients with HCA underwent hepatectomy at centers in Rio de Janeiro. They were included in the analysis patients undergoing hepatectomy with pathological diagnosis of hepatocellular adenoma and excluded patients with hepatectomy with anatomopathological diagnosis other than hepatocellular adenoma, mainly nodular focal hyperplasia. data related to patients, tumor and surgery were analyzed retrospectively. Results: Sixty patients (87%) were female and nine were male. Among women, 83% had a history of contraceptive use;among men, only one had an androgen intake history. Overall mean age was 36.4 years (15 - 49), with men older than women (33.9 ± 8.14 years vs. 40.4 ± 6.27 years;P = 0.02). Forty one patients reported abdominal pain, associated or not to other symptoms;32% had an episode of hemorrhage;28 were asymptomatic with an incidental radiological finding. In total, 45 patients presented only one lesion and overall mean size was 8.1 cm (2 - 31);tumors were larger among men (mean size 12.9 ± 9.86 cm vs. 7.7 ± 4.58 cm;P = 0.009). Twenty one surgeries were laparoscopic. Hepatocellular carcinoma (HCC) was identified in three specimens and the incidence was higher among men (22.2% vs. 1.6%;P = 0.042) and in tumors larger than 20 cm (66.6% vs. 0.02%). There was no perioperative mortality. Two of the three patients with HCC died with extrahepatic recurrence;the remaining patient is well after 36 months. Overall mean follow-up time was 14.2 months (2 - 76). Conclusion: Male patients with HCA were older and had larger tumors when compared to females. Incidence of HCC was higher among men and in lesions larger than 20 cm. Male patients with HCA should be

关键词： Hepatocellular Adenoma Hepatocellular Carcinoma Hepatectomy

Probabilistic Modeling of Oil Spills at the Exclusive Economic Zone of Cuba Using Petromar-3d Model

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Journal of Geoscience and Environment Protection 2021年第6期9卷 21-34页

作者： Alejandro Rodríguez dayron Chang Amilcar E. Calzada dayana Carracedo dailín Reyes Alexander Lobaina reinaldo Casals Jessica Hernández Javier Cabrales Institute of Meteorology of Cuba Havana Cuba Meteorology Office of Cuban Company for Air Navigation (ECNA - AISMet) Havana Cuba

This article shows the probabilistic modeling of hydrocarbon spills on the surface of the sea, using climatology data of oil spill trajectories yielded by applying the lagrangian model PETROMAR-3d. To achieve this goal, several computing and statistical tools were used to develop the probabilistic modeling solution based in the methodology of Guo. Solution was implemented using a databases approach and SQL language. A case study is presented which is based on a hypothetical spill in a location inside the Exclusive Economic Zone of Cuba. Important outputs and products of probabilistic modeling were obtained, which are very useful for decision-makers and operators in charge to face oil spill accidents and prepare contingency plans to minimize its effects. In order to study the relationship between the initial trajectory and the arrival of hydrocarbons spills to the coast, a new approach is introduced as an incoming perspective for modeling. It consists in storage in databases the direction of movement of the oil slick at the first 24 hours. The probabilistic modeling solution presented is of great importance for hazard studies of oil spills in Cuban coastal areas.

关键词： Oil Spill Modeling Petromar Lagrangian Model Probabilistic Modeling

Chemical Characterization and Cytotoxic Activity of Antarctic Macroalgae Extracts against Colorectal Cancer

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Advances in Biological Chemistry 2019年第5期9卷 167-177页

作者： Rafaele Frassini Yeslei Paulino da Silva Sidnei Moura Leonardo Zambotti Villela Aline Paternostro Martins Pio Colepicolo Mutue Toyota Fujii Nair S.Yokoya Claudio Martin Pereira de Pereira Vagner reinaldo Zingalli Bueno Pereira Joao Antonio Pegas Henriques Mariana Roesch-Ely Laboratory of Genomics Proteomics and DNA RepairUniversity of Caxias do SulCaxias do SulRSBrazil Laboratory of Biosynthetic and Natural Products of Caxias do Sul Caxias do SulRSBrazil Laboratory of Biochemistry and Molecular Biology of Algae University of Sao PauloSao PauloSPBrazil Phycologycal Research Institute of BotanySao PauloSPBrazil Laboratory of Lipidomics and Biorganic—LLipidomicaBio Federal University of PelotasPelotasRSBrazil General Hospital University of Caxias do SulCaxias do SulRSBrazil

Background/Aim: Antarctic seaweeds are considered a promising source of compounds with anticancer activity. Colorectal cancer (CRC) is one of the most incident cancers with high mortality rates worldwide. This work aimed to characterize chemically extracts of the Antarctic macroalgae Iridaea cordata, Cystosphaera jacquinotii and desmarestia anceps and to evaluate the cytotoxic effects against human colon cancer HCT 116 cell line. Materials and Methods: The extracts were obtained by depletion using an ultrasound probe and were identified by High-Performance Liquid Chromatography (HPLC) and Gas Chromatography coupled with Mass Spectrometry (GC-MS). Cell viability was determined by MTT assay. Results: Hexanic and chloroform extracts of the I. cordata and the hexanic, chloroform and methanolic extracts of d. anceps were able to inhibit growth of colorectal cancer cells in the three different incubation times (24, 48 and 72 h). Through GC analysis, 01 compounds were identified in the hexane extract and 02 compounds in the chloroform extract of the algae I. cordata. The hexane extract of d. anceps macroalgae presented 5 compounds, chloroform extract 10 and methanolic extract 3 respectively, with special highlight to fucosterol. Carotenoid analysis by HPLC identified β-carotene in all species, while zeaxanthin was present in the spectrum of I. cordata and C. jacquinotii. Fucoxanthin and violaxanthin were confirmed in the brown seaweeds C. jacquinotii and d. anceps. Conclusion: Extracts of macroalgae I. Cordata and d. anceps may be a source of therapeutic agents against CRC.

关键词： Antarctic Seaweeds Antitumor Activity Colorectal Cancer

Cellulose Acetate Film and Layered double Hydroxide as determination Method of Available Phosphorus in the Soil

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Journal of Agricultural Science and Technology(B) 2018年第7期8卷 420-432页

作者： Gustavo Franco de Castro Jader Alves Ferreira Allan Robledo Fialho e Moraes reinaldo Bertola Cantarutti Frederico Garcia Pinto Jairo Tronto Roberto Ferreira Novais department of Soil University of VicosaAv.Peter Henry RolfsBulding Silvyo Starling BrandaoCEP 36570-000Vicosa(MG)Brazil department of Chemistry University of VicosaRio Paranaiba CampusHighway MG-230KM 07CEP 38810-000Rio Paranaiba(MG)Brazil

The determination of available phosphorus(P)in soil is essential to the evaluation of the current fertility status,and therefore,for recommending the required phosphate fertilizers for the cultivation of *** mostly used extractants around the country are Mehlich-1(M-1)and anionic resins(AR)and mixed resins(MR).However,there are still controversies in relation to the method that should be used,due to of particularities of each ***,the main objectives of this work was to assess the applicability of films of binary combination between cellulose acetate(CA)biopolymer and calcinated layered double hydroxide(LdH-c),named CAF-LdH-c,as a new extractor of available P in *** this,two experiments were set *** the first one,sub-samples of an Oxisol layer 0-20 cm were used and submitted to increasing doses of total P(0,250,750 and 2,250 mg/dm3)in the form of monoammonium phosphate(MAP)at different incubation time(5,30,60 and 90 d).In the second experiment,samples of 20 soils from different origins and contents of available P were used with distinct chemical and physical *** analysis of available P by M-1,AR,MR,Mehlich-3(M-3)and CAF-LdH-c extractants was done in both *** efficiency of the extractants was evaluated by Pearson’s linear *** correlation between values of P extracted from soil in the first experiment was highly significant among all extraction methods used,including for *** the second experiment,CAF-LdH-c showed significant correlation(pd ***,the significant correlations of the extractant being tested(CAF-LdH-c)with those usually used indicates the possibility of this new method of routine laboratories for assessing the P availability of for the cultivation of crops.

关键词： Available P Mehlich-1 Mehlich-3 anionic resin mixed resin