Dissolução eletrolítica para a determinação de elementos de liga em aço ferramenta por ICP-AES

Different methods have been applied to solve special problems of metal analysis. First, the solid samples of tool steels were analyzed by X-ray fluorescence. Alternatively, an on-line electrodissolution implemented in a flow injection system and conventional dissolution procedure for determination of W, Mo, V and Cr in tool steels by ICP-AES is described. The resulting analyte solutions were compared with conventional dissolution procedure and determination by ICP-AES. The electrolytic procedure presented a good performance characterized by a sample throughput of 164 determinations per hour. Results were in agreement with those obtained by conventional acid dissolution.

El conformista de Bernardo Bertolucci: Alberto Moravia + Platón contra el fascismo

[spa] ¿Por qué Bernardo Bertolucci, al adaptar cinematográficamente la novela de Alberto Moravia Il conformista, introdujo en The Conformist la imagen platónica de la caverna? Este artículo preende dar respuesta a esta pregunta mediante el análisis de una parte considerable de la obra de Moravia.

El conformista de Bernardo Bertolucci: Alberto Moravia + Plató contra el feixisme

[cat] Per què Bernardo Bertolucci, en fer l’adaptació cinematogràfica de la novel·la d’Alberto Moravia Il conformista, introduí a The Conformist la imatge platònica de la caverna? Hom pretén donar resposta a aquesta pregunta mitjançant l’anàlisi de bona part de l’obra de Moravia.

Isolamento e avaliação da atividade nematicida de constituintes químicos de Mucuna cinerea contra Meloidogyne incognita e Heterodera glycines

Phytochemical investigation of the aerial parts and roots of Mucuna cinerea led to the isolation of a mixture of fatty acids, triacylglicerols, beta-sitosterol, stigmasterol, stigmasterol glucoside, daucosterol, asperglaucide (4) and the isoflavonoids prunetin (1), genistein (2), medicarpin (3), daidzein (5), 7-O-alpha-glycopiranosyl daidzein (6). An in vitro bioassay was carried out with compounds 1-4, at the concentration of 50 and 5 mug mL-1 against the phytonematodes M. incognita and H. glycines. Although the four compounds showed some nematocidal property, the most active was (1), causing 70% mortality of M. incognita at the concentration of 50 mug mL-1.

«M'encantaria poder venir a l'estadi a jugar contra el meu equip»: dixi de persona, footing i identitat, una entrevista a Pep Guardiola

Aquest article té dos objectius bàsics. En primer lloc, mostrar la capacitat analítica d'un estudi de cas a l'hora d'estudiar l'expressió de la identitat i dels rols assumits pels participants en la comunicació, posant-la en relació amb els marcs participatius d'Erwing Goffman (1981), d'una banda, i amb la dixi de persona i les seves manifestacions gramaticals (Levinson 1983; Nogué 2008), de l'altra. I en segon lloc, mostrar com l'estructura gramatical pot proporcionar indicadors lingüístics que donen informació sobre la identitat i els rols assumits, posant l'èmfasi en una circumstància concreta: la manera com es reflecteix lingüísticament la col¿lisió entre dos o més rols. Paraules clau: dixi de persona, identitat, rol participatiu, marc participatiu. This article has two main purposes. In the first place, to show how a case study can provide interesting information about the expression of identity and of the different roles assumed by the communication participants. On the one hand, this information is related to the participation frameworks proposed by Erwing Goffman (1981); on the other hand, to person deixis and its grammatical manifestations (Levinson 1983; Nogué 2008). And in the second place, to show how grammatical structure can provide linguistic cues about identity and roles, putting the emphasis on a specific circumstance: the linguistic signs of the collision between two or more of these roles. Key words: person deixis, identity, participation role, participation framework.

Ácidos siálicos: da compreensão do seu envolvimento em processos biológicos ao desenvolvimento de fármacos contra o agente etiológico da gripe

Sialic acids are nine-carbon carbohydrates that occur widely in nature and occupy the terminal portions of some glycoproteins and glycolipids of cell membranes. These carbohydrates are closely involved in cell-cell interactions and in processes such as microbial infection, inflammation, etc. Studies on the participation of sialic acids in biological processes have provided comprehension about their role in the infection by the influenza virus, the causal agent of flu. In this article, we present an overview of the importance of sialic acids in the influenza virus infection and how the knowledge of their involvement in this process has allowed the development of selective and efficient drugs against the virus.

Col·loqui amb Laura Mora, Marco Deriu, Núria Beitia i Clara Jourdan sobre les ponències del Seminari La democràcia igualitària i la violència contra les dones / La democracia igualitaria y la violencia contra las mujeres

Transcripció del col·loqui amb Laura Mora, Marco Deriu, Núria Beitia i Clara Jourdan sobre les ponències del Seminari 'La democràcia igualitària i la violència contra les dones'

La Violència contra les dones: una realitat política = La violencia contra las mujeres: una realidad política

Aquest any al seminari que organitzem al Centre de Recerca en Estudis de les Dones Duoda de la Universitat de Barcelona, ens hem proposat interrogar-nos, una vegada més, sobre una de les realitats humanes i polítiques mes crues en què es concreta el desordre que causa en alguns homes, en el present, el que anomenem el "final del patriarcat": la violència contra les dones. Aquesta violència, que ha existit des que va sorgir el patriarcat per a intentar apoderar-se de la paraula i del sentit del ser dona en el món, és ja expressable per a moltes dones a Occident i també a Orient

Concepções e ações de formadores de professores de química sobre o estágio supervisionado: propostas brasileiras e portuguesas

The purpose of this paper is to investigate lecturers'actions and conceptions about pre-service teaching practices in chemistry. In this sense, it takes into account several theoretical references concerned with teacher education, which support the qualitative analysis of 18 interviews, gathered with 14 brazilian and 4 portuguese lecturers. Results reveal that the pre-service teaching practices in chemistry have been performed far from a technical approach, showing a paradigmatic rupture and presenting another logic related with teacher education in chemistry, which have improved the comprehension of the teachers' real practices, since these have been shaped by complex and unprescribed factors.

De defensione Jehosuae, contra Satanam

Dedicatio: Petrus Brahe.

De juventute in religione christiana contra opinionem Rousseauianam instituenda

Invocatio: I.N.J.

Ações de divulgação de química na Casa da Descoberta - centro de divulgação de ciência da Universidade Federal Fluminense

This paper describes the main activities regarding scientific dissemination in the field of Chemistry at Casa da Descoberta (CD) - a Scientific Dissemination Center of the Fluminense Federal University. It presents a brief history of CD and discusses the difficulties concerning the dissemination of Chemistry at Scientific Dissemination Centers. This work also approaches some activities developed throughout the years: experiments performed in relation to the visitors' daily life, training of monitors to act as mediators in the non-formal teaching of Chemistry, production of dissemination materials, elaboration of books, as well as activities that relate formal to non-formal education.

Estudos de QSAR 2D baseados em descritores topológicos e fragmentos moleculares para uma série de derivados azólicos ativos contra Candida albicans

Azole derivatives are the main therapeutical resource against Candida albicans infection in immunocompromised patients. Nevertheless, the widespread use of azoles has led to reduced effectiveness and selection of resistant strains. In order to guide the development of novel antifungal drugs, 2D-QSAR models based on topological descriptors or molecular fragments were developed for a dataset of 74 molecules. The optimal fragment-based model (r² = 0.88, q² = 0.73 and r²pred = 0.62 with 6PCs) and descriptor-based model (r² = 0.82, q² = 0.79 and r²pred = 0.70 with 2 PCs), when analysed synergically, suggested that the triazolone ring and lipophilic properties are both important to antifungal activity.

Desenvolvimento e uso do compósito de Nb2O5|Cu como revestimento aplicado por aspersão térmica sobre o aço AISI 1020 para proteção contra a corrosão pelo solo em estruturas enterradas

An Nb2O|Cu corrosion-resistant coating was developed and applied onto AISI 1020 steel substrate by Powder Flame Spray. A galvanostatic electrochemical technique was employed, with and without ohmic drop, in four different soils (two corrosively aggressive and two less aggressive). Behavior of coatings in different soils was compared using a cathodic hydrogen reduction reaction (equilibrium potential, overvoltage and exchange current density) focusing on the effect of ohmic drop. Results allow recommendation of Nb2O5|Cu composite for use in buried structure protection.

Compostos orgânicos voláteis na defesa induzida das plantas contra insetos herbívoros

The identification and manipulation of chemical compounds involved in vital activities of arthropods have the potential for developing less aggressive pest control strategies. Herbivory induces the emission of volatile organic compounds involved in the recruitment of natural enemies, plant-plant interactions and repellency of other herbivores. In this report, we review the main chemical groups of volatile organic compounds and their ecological functions, provide an overview of the signal transduction pathways activated upon herbivory, and review the current state of knowledge for practical applications in pest management. We conclude by proposing perspectives for future research.