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Validation of Analytical Method for Chromatographic Determination of Chlorimuron Ethyl Herbicide in Sediments  [PDF]
Ramom Rachide Nunes, Bruno Henrique Froes Santos, Maria Olímpia Oliveira Rezende
Open Access Library PrePrints (OALib PrePrints) , 2014, DOI: 10.4236/oalib.preprints.1200090
Abstract: The present work describes the validation of an analytical method for chromatographic determination of chlorimuron ethyl herbicide (compound of sulphonylurea group) in sediments, in according with Brazilian legislation, following the guidance and normative documents of INMETRO (DOQ-CGCRE-008) and ANVISA (Resolution RE no 899 - 2003). The results show that the chromatographic method demonstrated to be selective, accurate, precision and linear over the concentration range of 5.0-1000.0 ug L-1. Besides, limits of quantitation and determination were satisfactory, 29.48 and 8.84 ug L-1, both determined by calibration curve. The method proposed also showed good results for assays of recovery, with confidence intervals between 80 and 100%, approximately, with accuracy and precision.
Electroflotation Applied to the Treatment of Wastewaters Containing Chlorimuron-Ethyl, a Sulfonylurea Herbicide  [PDF]
Ramom Rachide Nunes, Gabriel Muniz Morao, Maria Olímpia Oliveira Rezende
Open Access Library Journal (OALib Journal) , 2015, DOI: 10.4236/oalib.1101540
Abstract: Electroflotation (EF) is an electroanalytical technique commonly used for the separation of substances suspended in an aqueous phase. However, these studies are limited to the separation of wastes or contaminants, without destroying the contaminants. In this study, EF was applied as an advanced oxidation process, aiming to decontaminate wastewater containing sulfonylurea herbicides (chlorimuron-ethyl). Electroflotations were performed in an electroflotator reactor developed in the Laboratory of Environmental Chemistry, Institute of Chemistry of Sao Carlos, University of Sao Paulo, Brazil. The reactor was built in acrylic and was provided with aluminium electrodes. In addition, the anion electrode also was an agitation bar, that ensured the homogeneity of the solution during the process. Four assays were performed with varying salt concentrations (electrolyte-NaCl) and a direct electric current (I) was applied through the electrodes. Chemical monitoring was performed to determine the efficiency of the electrochemical process. Analysis of water samples by HPLC allowed the electrochemical reaction to be monitored, indicating a disturbance of the reaction medium (presence of byproducts of degradation). Gas chromatography coupled with mass spectrometry (GC-MS) was used to elucidate the mechanism of degradation and assist in the identification of the byproducts. According to the chromatograms obtained by HPLC-UV, the EF process changed the reaction medium, resulting in a displacement of the herbicide chromatographic peak and the appearance of bands without defined structure, related to the by-products generated. Based on the mass spectrum obtained, a mechanism of degradation was proposed, showing that EF does not totally destroy the chlorimuron-ethyl molecule, but it was successful in breaking important chemical bonds, responsible for the connection sulfonyl-urea. This study provides important information about the possibility of promoting the oxidation of toxic organic compounds by electroflotation, to generate less toxic and better environmentally adjusted effluents.
Analytical Procedures and Method Validation for Determination of Chlorimuron Ethyl in Sediments  [PDF]
Ramom Rachide Nunes, Bruno Henrique Froes Santos, Maria Olimpia de Oliveira Rezende
Open Access Library Journal (OALib Journal) , 2016, DOI: 10.4236/oalib.1102398
Abstract: The present work describes the validation of an analytical method for chromatographic determination of chlorimuron ethyl herbicide (compound of sulphonylurea group) in sediments, in according with Brazilian legislation, following the guidance and normative documents of INMETRO (DOQ-CGCRE-008) and ANVISA (Resolution RE no. 899-2003). The results show that the chromatographic method demonstrated to be selective, accurate, precision and linear over the concentration range of 5.0 - 1000.0 μg·L﹣1. Besides, limits of quantitation and determination were satisfactory, 29.48 and 8.84 μg·L﹣1, both determined by calibration curve. The method proposed also showed good results for assays of recovery, with confidence intervals between 80 and 100%, approximately, with accuracy and precision.
A New Simulated Annealing with Analytical Method for Identification of Unknown Ferromagnetic Parameters
Naamane Mohdeb,Mohammed Rachide Mekideche
Research Journal of Applied Sciences , 2012, DOI: 10.3923/rjasci.2010.65.72
Abstract: Simulated annealing algorithms are evolutionary processes that may well be applied to solve optimization problems under some hypotheses such as non-convexity and non-differentiability, etc. However, premature convergence is an intrinsic trait of such simulated annealing that makes them incompetent of searching best solution of the problem domain. In order to evade this problem, a new simulated annealing method for solving inverse electromagnetic problem is proposed. Adaptive simulated annealing is used as the new method in electrical engineering for solving the parameters identification problem. With the target as the metal under test, the calculation of the eddy current densities produced between the coil and the material is also detailed. Here the aim of the research explains the calculation procedure for the reactance and resistance of the eddy current sensor exited by voltage supply using a fast semi analytical method called coupled circuits method. Both the Coupled Electromagnetic Circuits Method (CECM) and the new approach (ASA) are used to estimate the electric conductivity and magnetic permeability of a circular material under test. To have the quality of this method, the performances of ASA are compared with other algorithm such as Genetic Algorithm (GA) in term of accuracy of the solution and computation time.
A Fast Hybrid Algorithm for Solving Materials Properties Determination Inverse Problem
Naamane Mohdeb,Mohammed Rachide Mekideche
IAENG International Journal of Computer Science , 2010,
Abstract:
Antimalarial Activity of 4-Metoxychalcones: Docking Studies as Falcipain/Plasmepsin Inhibitors, ADMET and Lipophilic Efficiency Analysis to Identify a Putative Oral Lead Candidate
Michael Eder de Oliveira,Gisele Cenzi,Renata Rachide Nunes,Carla Regina Andrighetti,Denia Mendes de Sousa Valad?o,Cláudia dos Reis,Cláudia Maria Oliveira Sim?es,Ricardo José Nunes,Moacyr Comar Júnior,Alex Gutterres Taranto,Bruno Antonio Marinho Sanchez,Gustavo Henrique Ribeiro Viana,Fernando de Pilla Varotti
Molecules , 2013, DOI: 10.3390/molecules181215276
Abstract: Herein, we report the antimalarial activity of nine 4-methoxychalcone derivatives 1a– i and an initial analysis of their ADMET properties. All compounds showed potent activity against the P. falciparum chloroquine-resistant clone W2, with IC 50 values ranging from 1.96 μM to 10.99 μM, with moderate or low cytotoxicity against the HeLa cell line. The compound 1a (IC 50 = 2.06 μM) had the best selectivity index (9.0). All the sulfonamide 4-metychalcone derivatives synthesized had cLogP values between 2 and 5 (mean value 3.79) and molecular weights (MWs) below 500. The substitution of the pyrrolidine group in 1i by a morpholine group in 1a reduced the cLogP value from 3.05 in compound 1i to 2.34 in compound 1a. Indeed, compound 1a had the highest LipE value. The binding free energy of compound 1a showed it to be the most optimal chalcone derivative for plasmepsin-2 (?7.3 Kcal/mol). The physicochemical properties and LipE analysis of the dataset allowed us to establish that compound 1a is the highest quality compound of the series and a potential oral lead candidate.
Vencendo a escassez de recursos computacionais. Carvalho: Tradutor Automático Estatístico Inglês-Galego a partir do corpus paralelo Europarl Inglês-Português.
Paulo Malvar,José Ramom Pichel,óscar Senra,Pablo Gamallo
Linguamática , 2010,
Abstract: à hora de desenvolver muitas ferramentas estatísticas de Processamento da Linguagem Natural torna-se essencial a utiliza o de grandes quantidades de dados. Para salvar a limita o da escassez de recursos computacionais para línguas minorizadas como o galego é necessário desenhar novas estratégias. No caso do galego, importantes romanistas têm teorizado que galego e português s o variantes do português europeu. De um ponto de vista pragmático, esta hipótese poderia abrir uma nova linha de investiga o para fornecer ao galego ricos recursos computacionais. Partindo do corpus paralelo inglês- português Europarl, imaxin|software compilou um corpus paralelo inglês-galego que utilizamos para criar um protótipo de tradutor automático estatístico inglês-galego, cuja performance é comparável a Google Translate. Mantemos que é possível implementar esta estratégia para desenvolver uma grande variedade de ferramentas computacionais para línguas, como o galego, intimamente relacionadas com línguas que já contam com um grande repertório de recursos computacionais.
A New Governance Model for Independent Regulatory Agencies  [PDF]
Rui Nunes, Sofia B. Nunes, Guilhermina Rego
Theoretical Economics Letters (TEL) , 2015, DOI: 10.4236/tel.2015.51002
Abstract: In a regulatory state the purpose of intervention by any Independent Regulatory Agency (IRA) is not only regulation in the strict sense but also the supervision of the activity of institutions providing a specific service, particularly the utilities. However, given the evolution of most market economies, namely in transition countries, it is necessary to design new governance arrangements that enable an effective, transparent and truly independent intervention of IRAs. The objectives of this study are a) to analyse of the institutional-design chosen for some independent regulatory agencies and its regulatory framework, namely in northern economies, and b) to suggest the need to strengthen governance arrangements to effectively guarantee regulatory independence, transparency and accountability, therefore promoting a true sunshine regulation in southern economies. The authors conclude that strengthening accountability arrangements is the most important mechanism to avoid regulators capture from the government and regulated organisations. It is also concluded that the way regulators have chosen can also influence the way IRA conducts its activity. Therefore, it is suggested that board accountability can be enhanced by the generalization of the principle of the public contest of regulators.
Hospital Foundation: A SWOT Analysis  [PDF]
Guilhermina Rego, Rui Nunes
iBusiness (IB) , 2010, DOI: 10.4236/ib.2010.23026
Abstract: The reform of Portuguese public hospitals can be described as an evolution by “waves”. A first “wave” took place in 2002, when 34 public hospitals were transformed into State-owned hospital enterprises (SA hospitals). Subsequently, in January 2006, the SA hospitals and some of the traditional public administration hospitals (SPA hospitals) were changed into public business enterprises (EPE hospitals). That was the second “wave” that is the stage we are at pre- sent. A possible third “wave” can be related with the possibility of conversion of the EPE hospitals into State Hospital Foundations (SHF). This paper tries to identify if this new management model has more capacity to influence positively values such as efficiency, equity, quality, governance, empowerment and accountability than the previous existing model. For this purpose it was developed a strategic analysis including an evaluation of some internationals experi- ences, and also a SWOT analysis was performed. The authors conclude that the introduction of SHF model is a very plausible alternative. The model of governance can make the difference and promote its implementation. Due to the participative management model, the process of accountability can be more “visible” and the regulatory process of this management model seems to be more effective.
Interactive Digital Games for Geography Teaching and Understanding Geographical Space  [PDF]
Christian Nunes da Silva
Creative Education (CE) , 2015, DOI: 10.4236/ce.2015.67070
Abstract: This article aims to analyze and discuss the use of digital interactive games, such as learning tools to be used by educators in the classroom, as a resource for geography teaching-learning process in the early grades. This discussion arose from the analysis by geography course graduation students of the Federal University of Pará (UFPA), in the years 2013 and 2014, at which this tool has gained recognition of its potential by students. In this sense, the objective is a brief discussion, based on the analysis of some selected examples on how these digital games can become fundamental importance of resources for teaching Geography and how these should be used and applied in the classroom by educators in a critical way, which will allow students to have adequate learning about the geographic space.
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