WorldWideScience

Sample records for bronze marcos da

  1. The analysis of bronze alloys from the equestrian statue of Marco Aurelio by means of a thin sample XRF technique

    Science.gov (United States)

    Ferretti, M.; Cesareo, R.; Marabelli, M.; Guida, G.

    1989-02-01

    The choice of the methods that can be employed in the elemental characterization of archaeological alloys strongly depends on the type, state of conservation and dimensions of the object. The present article describes the analytical approach used for the bronze equestrian statue of Marco Aurelio, for which "in loco" nondestructive analyses could not be performed. The technique is based on the XRF analysis of samples that were previously cored from the statue in small quantities (200 mg), dissolved and deposited on a support in the form of a thin layer. The article also shows some of the results concerned with the analysis of approximately 100 samples; such results were found to be in good agreement with the typical compositions of ancient bronzes.

  2. Bullying e ciberbullying: Marco normativo e prevalencia nas etapas da educación básica

    OpenAIRE

    López Gómez, Nahyr

    2015-01-01

    [GAO] O presente traballo pretende afondar nos fenómenos do bullying e do ciberbullying, analizar o marco normativo no que se insiren e indagar acerca da situación actual dos mesmos nas etapas da educación básica: Educación Primaria e Educación Secundaria Obrigatoria. Para acadar ditos obxectivos levouse a cabo unha revisión bibliográfica sobre ambas problemáticas e unha minuciosa revisión das investigacións máis recentes desenvolvidas no ámbito estatal e autonómico. Tras realizar dita aná...

  3. Tecnologia no cuidado de enfermagem: uma análise a partir do marco conceitual da Enfermagem Fundamental

    Directory of Open Access Journals (Sweden)

    Rafael Celestino da Silva

    2014-01-01

    Full Text Available Pesquisa de campo, qualitativa, cujo objetivo foi discutir a aplicação de tecnologias no cuidado de enfermagem na terapia intensiva, tomando como referência o marco teórico-conceitual da Enfermagem Fundamental. Realizou-se observação e entrevista com vinte e dois enfermeiros de uma unidade de terapia intensiva, com análise etnográfica. A tecnologia, a partir do domínio de uma linguagem tecnológica, fornece condições para que os fundamentos do cuidado de enfermagem possam ser efetivamente incorporados à prática do enfermeiro. A ideia de desumanização ligada à tecnologia pode ser explicada pelo modo como o enfermeiro significa as coisas afetas ao seu cotidiano, o qual orientará sua ação. Conclui-se que as tecnologias ajudam a promover a vida e resgatar o humano.

  4. Marcos legais da propaganda de medicamentos: avanços e retrocessos Legal frameworks of drug advertisement: progress and setbacks

    Directory of Open Access Journals (Sweden)

    Carolina Pires Araújo

    2012-01-01

    Full Text Available Desde o início da civilização brasileira, já existe divulgação de produtos farmacêuticos, sendo os medicamentos os preferidos dos anúncios. A propaganda de medicamentos, enquanto estratégia persuasiva, pode representar risco sanitário, caso não se comprometa com a divulgação de informação correta e segura. Nesse sentido, várias são as tentativas de controle sanitário por parte do Estado, as quais parecem consolidar-se em embates de domínio ético e legal. Em busca de compreender o contexto que norteia a atual conjuntura da problemática sobre propaganda de medicamentos, o presente estudo traça um percurso histórico, a partir dos principais marcos legais: a Junta Central de Higiene (1851, a Lei de Vigilância Sanitária (1976 e a criação da ANVISA (1999. Identificou-se que os marcos acompanham o contexto estrutural do país, contribuindo para a consolidação do campo da regulação hoje.Since the beginning of Brazilian civilization, there is already disclosure of pharmaceutical drugs being the favorite of the ads. The advertising of medicines, while persuasive strategy, may represent health risk, if not compromised with the release of accurate and safe information. For that reason, there are several attempts at sanitary control by the state, which appears to be consolidated in the struggles of the ethical and legal domain. In seeking to understand the context that guides, the current situation of the drug advertising problem, this study provides a historical background, from the main legal frameworks: "Junta Central de Higiene" (1851, "Lei de Vigilância Sanitária" (1976 and the creation of "ANVISA" (1999. It was identified that milestone follows the country structural context, contributing to the consolidation of the regulation's field nowadays.

  5. AVANÇOS E PERSPECTIVAS DA RENAME APÓS NOVOS MARCOS LEGAIS: O DESAFIO DE CONTRIBUIR PARA UM SUS ÚNICO E INTEGRAL

    Directory of Open Access Journals (Sweden)

    José Miguel do Nascimento Júnior

    2015-10-01

    Full Text Available Objetivos: O presente artigo tem por objetivo descrever o processo de atualização da Relação Nacional de Medicamentos Essenciais (RENAME, contextualizando-o à luz de novos marcos legais do Sistema Único de Saúde (SUS. Métodos: Trata-se de um estudo descritivo, de natureza crítica-reflexiva, estruturado em dois momentos: a o processo de atualização da RENAME com a instituição dos novos marcos legais e b discussão dos avanços, desafios e perspectivas da RENAME com o advento dos marcos legais descritos. Resultados: Discute-se a nova concepção da RENAME e sua harmonização com as diretrizes do SUS, discorrendo sobre aspectos dos processos de incorporação, de responsabilização pelo financiamento e de pactuação interfederativa, e seus impactos no acesso aos medicamentos. Conclusões: As mudanças nos marcos legais contribuíram para a aproximação das políticas de incorporação tecnológica e de assistência farmacêutica no âmbito do SUS, tornando a nova RENAME um instrumento importante para a qualificação da gestão e para a garantia do acesso a medicamentos eficazes, efetivos e seguros à população brasileira. Descritores: Medicamentos Essenciais; Assistência Farmacêutica; Gestão em Saúde; Financiamento da Assistência à Saúde; Sistema Único de Saúde.  

  6. NANOMEDICAMENTOS E OS DESAFIOS DA ANVISA DIANTE DA INEXISTÊNCIA DE UM MARCO REGULATÓRIO NO BRASIL

    Directory of Open Access Journals (Sweden)

    Liziane Paixão Silva Oliveira

    2016-08-01

    Full Text Available A nanotecnologia, em razão de suas propriedades singulares, pode proporcionar inúmeros benefícios em diversas áreas estratégicas: saúde, eletrônica, alimentação, agricultura, meio ambiente entre outras. Um dos ramos mais promissores é o desenvolvimento e comercialização de nanomedicamentos que prometem revolucionar o campo de aplicação da medicina. No Brasil, a Agência Nacional de Vigilância Sanitária (ANVISA, que tem suas atribuições definidas na Lei nº 9.782/1999, é o órgão responsável por fiscalizar a produção e a comercialização desses novos medicamentos. Nesse artigo, será dado enfoque aos desafios da ANVISA considerando a existência de nanomedicamentos no mercado de consumo que não são identificados ou reconhecidos como tais pela vigilância sanitária diante da inexistência de uma norma regulatória nacional.

  7. DA PROTEÇÃO AO AMBIENTE DO TRABALHO: OS NOVOS MARCOS DEFINIDORES DO RISCO NO TRABALHO

    Directory of Open Access Journals (Sweden)

    Lourival José de Oliveira

    2012-04-01

    Full Text Available RESUMOO meio ambiente do trabalho deve ser entendido como um bem público. Deste entendimento deriva uma compreensão diferente no que se refere principalmente à sua proteção. A aplicação da teoria da responsabilidade subjetiva, seja qual for a hipótese, encontra-se em descompasso com os valores erigidos constitucionalmente. A nova realidade empresarial, os novos modelos gerenciais, a nova dinâmica imposta no cotidiano do trabalho fez nascer características próprias no trabalhador, conhecidas no seu conjunto como sendo um novo subjetivismo, marcado pelo individualismo exacerbado principalmente. No mesmo passo surgiu a necessidade de compreender os riscos inerentes a este novo ambiente de trabalho, os quais devem ser mensurados de maneira a apreendê-los sem o rigorismo empírico manifesto na maioria das hipóteses. Ou seja, por exemplo, nexo de causalidade deixou de ser algo a ser necessariamente demonstrado, partindo-se do pressuposto que o ambiente de trabalho pode ser compreendido como um estado permanente de risco. A reparação do dano já ocorrido vem em desacordo com as proteções contidas no texto constitucional, valendo citar de forma expressa os artigos 1º e 170 principalmente. Nasce a necessidade de desenvolver as formas preventivas, ou seja, instrumentos que possam evitar a eclosão do dano, considerando este procedimento como o efetivamente legitimado constitucionalmente. Os marcos definidores do risco empresarial, as formas de sua apuração, o entendimento sobre a proteção a ser construída em torno do valor trabalho humano precisam sofrer grandes mudanças, sob pena de continuar em descompasso com a nova dinâmica empresarial, trazendo por conseqüência prejuízos irreversíveis ao ambiente do trabalho. Palavras- chave: ambiente de trabalho, reestruturação produtiva, risco no trabalho, dignidade no trabalho. PROTECTION OF THE ENVIRONMENT AT WORK: NEW LANDMARKS DEFINING THE RISK IN THE WORKPLACE ABSTRACT The work

  8. A caracterização da lógica pela força assertórica em frege. Resposta a Marco Ruffino

    Directory of Open Access Journals (Sweden)

    Dirk Greimann

    2012-06-01

    Full Text Available Segundo a caracterização padrão da lógica nos escritos fregeanos, a palavra "verdadeiro" indica a essência da lógica, assim como a palavra "bom" indica a essência da ética e a palavra "belo" a essência da estética. Num escrito póstumo de 1915, porém, Frege afirma que é a força assertórica, e não a palavra "verdadeiro", que indica a essência da lógica. Prima facie, esta correção está em conflito com a crítica fregeana à concepção psicologista da lógica. Pois, segundo esta crítica, a lógica não é a ciência das leis "do ser tomado como verdadeiro", mas a ciência das leis "do ser verdadeiro", ao passo que a força assertórica expressa o ser tomado como verdadeiro. Em escritos anteriores, tentei resolver este conflito por uma reconstrução da concepção fregeana da verdade baseada na tese fregeana de que verdade é expressa na linguagem natural pela "forma da sentença assertórica". A meta do presente trabalho é defender esta interpretação contra as objeções recentemente feitas por Marco Ruffino.

  9. Arranjos Produtivos Locais na Perspecitva da Teoria do Capital Social: Um Estudo no Cluster Moveleiro de Marco (CE

    Directory of Open Access Journals (Sweden)

    Tereza Cristina Batista de Lima

    2011-11-01

    Full Text Available This study aimed to describe a local productive arrangement from the viewpoint of social capital theory, adopting a cognitive, relational and structural outlook remarking collective action to achieve common goals with wealth production. The research is qualitative, descriptive, documental and field, in the case study method. It took place at furniture cluster of Marco, state of Ceará – Brazil, by its longevity and results reported. Data collecting was done through semistructured interviews with 25 subjects institutionally significant inside the APL value chain. The study allowed to describe the social capital dynamics which sustain the furniture cluster results in terms of strengths, weaknesses and contradictions, as well as the interactions underlying the development of skills that promote individual and collective outcomes. Thus, the study also highlights the role of coordination, mobilization and organization of the human factor for the individual, institutional and territory economic and social development.

  10. Por uma Nova Concepção de Empresa no Marco da Sociedade do Risco: do lucro inconsequente à responsabilidade socioambiental

    Directory of Open Access Journals (Sweden)

    Daniel Piovanelli Ardisson

    2012-07-01

    Full Text Available This paper seeks to demonstrate the evolution of the legal concept of enterprise between two historical socio-economic milestones: the industrial society of the late nineteenth century and the contemporary risk society. Based on an analysis of economics and commercial law at the end of the nineteenth century, it is initially explained that the legal notion of enterprise then used, influenced by the industrial capitalism, was defined by an economic bias and focused itself exclusively in maximizing production efficiencyand profit.Resumo: O presente artigo busca demonstrar a evolução do conceito jurídico de empresa à luz de dois marcos socioeconômicos históricos: a sociedade industrial do final do século XIX e a sociedade do risco contemporânea. Partindo de uma análise da teoria econômica e do direito comercial ao final do século XIX, expõe-se inicialmente que a noção jurídica de empresa então vigente, influenciada pelo capitalismo industrial, era definida por um viés econômico e se focava exclusivamente na maximização da eficiência produtiva e do lucro.

  11. Estudio de la caída libre desde marcos de referencia no inerciales usando herramientas computacionales

    OpenAIRE

    John Hernán Díaz Forero; Miguel José Espitia Rico; Edison Francisco Cudris García

    2014-01-01

    Se elaboró una propuesta para la enseñanza e implementación del modelo de Galileo (descripción del movimiento del punto material —partícula— en el espacio y en el tiempo) en los cursos de física para ciencias e ingeniería, realizando una clase de física mediante la resolución de problemas no convencionales, específicamente la descripción de la caída libre desde sistemas de referencia no inerciales. En particular, se considera en el espacio bidimensional de coordenadas un observador inercia...

  12. Estudio de la caída libre desde marcos de referencia no inerciales usando herramientas computacionales

    Directory of Open Access Journals (Sweden)

    John Hernán Díaz Forero

    2014-05-01

    Full Text Available Se elaboró una propuesta para la enseñanza e implementación del modelo de Galileo (descripción del movimiento del punto material —partícula— en el espacio y en el tiempo en los cursos de física para ciencias e ingeniería, realizando una clase de física mediante la resolución de problemas no convencionales, específicamente la descripción de la caída libre desde sistemas de referencia no inerciales. En particular, se considera en el espacio bidimensional de coordenadas un observador inercial en el origen de coordenadas, que percibe un sistema de dos partículas con la propiedad masa m, con diferentes posiciones iníciales y velocidades iniciales, que están en presencia del campo gravitacional g , y se resuelve el problema desde sistemas de referencia no inerciales montados en las partículas 1 y 2. Se realizó una animación apoyados en el uso de nuevas tecnologías computacionales (el software Interactive Physics.

  13. Crystallographic analysis of the solid solution of iron doped potassium strontium niobate with tetragonal tungsten bronze structure; Analise cristalografica da solucao solida com estrutura tipo Tungstenio Bronze de niobato de potassio e estroncio dopado com ferro

    Energy Technology Data Exchange (ETDEWEB)

    Lanfredi, Silvania; Nobre, Marcos A.L., E-mail: silvania@fct.unesp.b [UNESP, Presidente Prudente, SP (Brazil). Faculdade de Ciencias e Tecnologia. Dept. de Fisica, Quimica e Biologia; Lima, Alan R.F. [Universidade Estadual de Ponta Grossa (DQ/UEPG), PR (Brazil). Dept. de Quimica

    2010-07-01

    Solid solution of iron doped potassium strontium niobate with KSr{sub 2}(FeNb{sub 4})O{sub 15-{delta}} stoichiometry was prepared by high efficiency ball milling method. Structural characterization was carried out by X-ray diffraction. Crystalline structure was analyzed by the Rietveld refinements using the FullProf software. The results showed a tetragonal system with the tetragonal tungsten bronze structure - TTB (a = 12.4631 (2) A and c = 3.9322 (6) A, V = 610.78 (2) A{sup 3}). In this work, the sites occupancy by the K{sup +}, Sr{sup 2+} and Fe{sup 3+} cations on the TTB structure were determined. NbO{sub 6} polyhedra distortion and its correlation with the theoretical polarization are discussed. (author)

  14. Scientific framework of homeopathy: evidence-based homeopathy Marco científico de la homeopatía: homeopatía basada en evidencia Marco científico da homeopatia: homeopatia baseada em evidências

    Directory of Open Access Journals (Sweden)

    Michel Van Wassenhoven

    2008-06-01

    Full Text Available This paper aims at considering all important aspects of the scientific framework of homeopathic practice, looking at the levels of scientific evidence of each aspect in an objective way, through an extensive review of literature. Levels of evidence considered are: I existence of meta-analyses and/or systematic positive reviews of literature; IIa multiple positive randomized controlled trials (RCTs; IIb some positive RCTs; IIIa positive multiple cohorts studies; IIIb positive studies with some cohorts; IV opinion of experts (clinical and daily practice cases. Conclusions are clear: homeopathy must stay within the framework of medical practice, and it is even a necessity for public health. Keywords: Evidence-Based medicine, Homeopathy, Scientific framework, Literature review.   Marco científico da homeopatia: homeopatia baseada em evidências Resumo O presente artigo aborda aspectos importantes do marco científico da prática homeopática, focando os níveis de evidência de cada um deles de maneira objetica, através de uma revisão extensa da literatura. Os níveis de evidência considerados são: I existência de meta-análises e/ou revisões sistemáticas positivas da literatura; IIa múltiplos estudos randomizados controlados (RCTs positivos; IIb alguns RCTs positivos; IIIa estudos de coortes múltiplas positivos; IIIb estudos com algumas coortes positivos; IV opinião de expertos (casos clínicos da prática cotidiana. As conclusões são claras: a homeopatia deve permanecer dentro do marco da prática médica, sendo, inclusive, uma necessidade para a saúde pública. Palavras-chave: Medicina Baseada em Evidências, Homeopatia, Estrutura ciêntifica, Revisão de literatura.   Marco científico de la homeopatía: homeopat

  15. con marcos extradensos

    Directory of Open Access Journals (Sweden)

    Manuel Rodríguez

    2007-01-01

    Full Text Available El cultivo del plátano vianda al igual que el de la papaya, en la región occidental del país, son fuertemente atacados por enfermedades que hacen que las plantaciones, por el grado de deterioro que estas les producen, no duren más de un ciclo de cultivo. Sembrar una misma área, un año tras de otro con el mismo cultivo, trae consigo el establecimiento en el suelo de elementos parásitos dañinos al mismo, que pueden ser eliminados o atenuados con una rotación con otro cultivo. El presente trabajo expone los resultados experimentales de dos años de trabajo de la rotación de estos cultivos, plantados con dos marcos de plantación de alta densidad, 2 x 4 x 1 m y 3 x 1 m, con una densidad de 3333 plantas/ha y regados con la técnica de riego por goteo. Se obtuvieron rendimientos de 40,73 t/ha en plátano y de 71,42 t/ha en papaya, con una relación beneficio costo de 1,15, tasa interna de retorno de 36,27 %, valor actual neto de 21,47 y plazo de recuperación de la inversión de 3,01 años.

  16. Bronze rainbow hologram mirrors

    Science.gov (United States)

    Dawson, P.

    2006-02-01

    This project draws on holographic embossing techniques, ancient artistic conventions of bronze mirror design and modelling and casting processes to accomplish portraiture of reflection. Laser scanning, 3D computer graphics and holographic imaging are employed to enable a permanent 3D static holographic image to appear integrated with the real-time moving reflection of a viewer's face in a polished bronze disc. The disc and the figure which holds it (caryatid) are cast in bronze from a lost wax model, a technique which has been used for millennia to make personal mirrors. The Caryatid form of bronze mirror which went through many permutations in ancient Egyptian, Greece and Rome shows a plethora of expressive figure poses ranging from sleek nudes to highly embellished multifigure arrangements. The prototype of this series was made for Australian choreographer Graeme Murphy, Artistic Director of the Sydney Dance Company. Each subsequent mirror will be unique in figure and holographic imagery as arranged between artist and subject. Conceptually this project references both the modern experience of viewing mirrors retrieved from ancient tombs, which due to deterioration of the surface no longer reflect, and the functioning of Chinese Magic mirrors, which have the ability to project a predetermined image. Inspired by the metaphorical potential of these mirrors, which do not reflect the immediate reality of the viewer, this bronze hologram mirror series enables each viewer to reflect upon himself or herself observing simultaneously the holographic image and their own partially obliterated reflection.

  17. Bronze Age Acrobats

    DEFF Research Database (Denmark)

    Iversen, Rune

    2014-01-01

    immaterial, ritual and cosmological exchange that characterized the second and early firstmillennium BC.Beliefs and ritual practices went hand in hand with the adoption of a series of elite items and an aristocratic lifestyle, thereby creating a unique and fascinating European Bronze Age....

  18. Vegetables, Coctails & Reflections / Marco Laimre

    Index Scriptorium Estoniae

    Laimre, Marko, 1968-

    2006-01-01

    Pealkirja "Vegetables, Coctails & Reflections" kandis Tallinna Kunstihoones 8.04.-28.05.2006 avatud Elin Kardi, Marko Mäetamme, Marco Laimre ja Andres Tali ühisnäitusel "Vägivald ja propaganda" Marco Laimre installatsioon. Marco Laimre esinemine raadiosaates "kunst.er" Klassikaraadios 16.04.2006

  19. Marco Calamari, La scomparsa della rete

    Directory of Open Access Journals (Sweden)

    Maria Chiara Pievatolo

    2011-12-01

    Full Text Available Chi era in rete prima che fosse invasa dalle moltitudini – scrive Marco Calamari su “Punto Informatico” – temeva principalmente la sua occupazione “militare” da parte degli stati,  tramite una censura e un controllo capillare. Non è andata esattamente così. L’”economia del dono“, per la sua eccellenza tecnica, ha retto alla pressione delle masse e [...

  20. LEVANTAMENTO DE BRIÓFITAS BIOINDICADORAS DE PERTURBAÇÃO AMBIENTAL DO CAMPUS MARCO ZERO DO EQUADOR DA UNIVERSIDADE FEDERAL DO AMAPÁ

    OpenAIRE

    Cristiane Rodrigues Menezes; Klíssia Calina de Souza Gentil

    2011-01-01

    No mundo todo são conhecidas cerca de 18.000 espécies de briófitas; para o Brasil são citadas 3.125 espécies, distribuídas em 450 gêneros e 110 famílias. Os estudos de briófitas para algumas regiões do Brasil ainda são escassos ou abrangem áreas restritas, como é o caso da região Norte. Essas lacunas de conhecimento não permitem um maior embasamento para discutir a riqueza de espécies entre diferentes regiões brasileiras com detalhes. O presente trabalho foi realizado no campus da Universidad...

  1. Marcos referenciais da trajetória das políticas de alimentação e nutrição no Brasil Milestones of the feeding policies and nutrition in Brazil

    Directory of Open Access Journals (Sweden)

    Bertoldo Kruse Grande de Arruda

    2007-09-01

    Full Text Available Os marcos que influenciaram a concepção e a implementação de propostas inovadoras no campo da nutrição surgiram na década de 30. O inquérito promovido por Josué de Castro no Recife, em 1933, sobre as condições de vida das classes operárias revelou a ocorrência de déficit calórico e de nutrientes e motivou o desenvolvimento de novas pesquisas acerca da situação alimentar em Pernambuco, Rio de Janeiro e São Paulo, estabelecendo as relações entre alimentação e salário mínimo. Para dar assistência ao governo na formulação da Política Nacional de Alimentação e Nutrição foi criado o Instituto Nacional de Alimentação e Nutrição (INAN, em 1972, e elaborado o I Programa Nacional de Alimentação e Nutrição (PRONAN, envolvendo 12 subprogramas das diversas estruturas governamentais e, com olhar inovador da desnutrição como uma doença social foi substituído, em 1976, pelo II PRONAN. A extinção do INAN, em 1997, conduziu ao surgimento da Coordenação Geral da Política de Alimentação e Nutrição, responsável pela elaboração da Política Nacional de Alimentação e Nutrição no contexto da Segurança Alimentar e Nutricional, criando em 2001 o Programa Bolsa Alimentação. A criação do Conselho Nacional de Segurança Alimentar, em 1993, fomentou a aprovação do Programa Fome Zero. Identifica-se que na realidade brasileira, a avaliação das políticas públicas é um campo tradicionalmente marcado pela carência de procedimentos sistemáticos.The milestones of the concept and implementation of innovative proposals in the field of nutrition appeared in the 30's. The 1933 survey performed by Josué de Castro in Recife focusing the qualify of life of the working classes determined calories' and nutrients' deficiencies and encouraged the development of new researches focusing on the food situation in Pernambuco, Rio de Janeiro and São Paulo, esta-blishing a relationship between food and minimum wage. To

  2. Bronze (Âge du)

    OpenAIRE

    Camps, G.

    2012-01-01

    En un siècle et demi de recherche archéologique, l’Afrique du Nord a livré moins d’une trentaine d’armes ou d’instruments en cuivre ou en bronze qui soit parvenue à la connaissance des spécialistes. Comment expliquer cette carence ? La rareté des objets métalliques attribuables au Chalcolithique ou à l’Âge du bronze demeure l’un des problèmes non résolus de la Protohistoire maghrébine. Armes de cuivre ou de bronze 1. Hache de l’oued Akrech ; 2. Hache en cuivre du Kef el Baroud ; 3. Hache en ...

  3. Marco Grippeling (1966-2014)

    CERN Multimedia

    2014-01-01

    It was with great sadness that we learnt that our former colleague and friend Marco Grippeling was amongst the victims of the Malaysia Airlines crash.   Marco, a Melbourne-based cyber security specialist, boarded flight MH17 on his way back to Australia after spending his last days with friends and family in his home country of the Netherlands. Marco joined CERN as a Technical Student in the PS Division in 1992.  In 1994 he moved to the LHC Division as a Staff Member, leaving for more exotic horizons in 2000. Marco will always be remembered for his enthusiasm and joie de vivre. Our deepest condolences go to his family and friends at this time. His former colleagues and friends at CERN

  4. Ancient Chinese Bronzes: Teacher's Packet.

    Science.gov (United States)

    Smithsonian Institution, Washington, DC. Arthur M. Sackler Gallery.

    The focus of this teacher's packet is the bronze vessels made for the kings and great families of the early Chinese dynasties between 1700 B.C. and 200 A.D. The materials in the guide are intended for use by teachers and students visiting the exhibition, "The Arts of China," at the Arthur M. Sackler Gallery of the Smithsonian Institution in…

  5. Bronze Statuettes in Roman Graves

    Directory of Open Access Journals (Sweden)

    Margherita Bolla

    2014-02-01

    Full Text Available This research follows the investigations about the relationship between bronze statuettes and contexts in Roman times, particularly explored by Annemarie Kaufmann-Heinimann. The rarity of bronze figures (human, divine and animals in Roman tombs of Imperial age has been repeatedly emphasized. The aim of the paper is the collection, not exhaustive, of evidences in funerary contexts, to determine their meaning. From a methodological point of view, it was necessary to exclude figurines placed in graves but with other originary functions and several bronzes whose finding in tombs is unreliable. This preliminary survey has given about eighty all-round bronzes from burials, distributed in different areas, both in the Empire and marginal. Considering the huge amount of Roman burials known today, the overall evidence is scarce but allows some observations; it is evident the pre-eminence of Venus and Mercury, gods which had a funerary role. There is also an attempt to find the reasons of the rarity of metal statuettes in the tombs of roman period.

  6. Surface and electrocatalytic properties of tungsten bronzes

    International Nuclear Information System (INIS)

    Tafel plots have been obtained for the oxygen reaction in acid solution on several alkali tungsten bronzes having different crystal structures. Platinum doped sodium tungsten bronze crystals were studied and the results compared with those of platinum free crystals of the same composition. In both cases sodium tungsten bronzes were found to be poor electrocatalysts for the cathodic reduction of oxygen. Similar results are reported for other alkali tungsten bronzes and for tungsten trioxide. Anodic treatment of the crystals affected the electrocatalytic activity of only the sodium tungsten bronze and the effect was a negative one. Cyclic voltammetry was employed to study the effects of the anodic treatment which created a sodium depletion layer on the sodium tungsten bronze surface. The existence and depth of the sodium depletion layer was determined by an Auger Electron Spectroscopy depth profile

  7. Surface and electrocatalytic properties of tungsten bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Weber, M.F.; Shanks, H.R.

    1977-01-01

    Tafel plots have been obtained for the oxygen reaction in acid solution on several alkali tungsten bronzes having different crystal structures. Platinum doped sodium tungsten bronze crystals were studied and the results compared with those of platinum free crystals of the same composition. In both cases sodium tungsten bronzes were found to be poor electrocatalysts for the cathodic reduction of oxygen. Similar results are reported for other alkali tungsten bronzes and for tungsten trioxide. Anodic treatment of the crystals affected the electrocatalytic activity of only the sodium tungsten bronze and the effect was a negative one. Cyclic voltammetry was employed to study the effects of the anodic treatment which created a sodium depletion layer on the sodium tungsten bronze surface. The existence and depth of the sodium depletion layer was determined by an Auger Electron Spectroscopy depth profile.

  8. Decorative layers on tin bronzes

    Directory of Open Access Journals (Sweden)

    Z. Konopka

    2010-10-01

    Full Text Available Decorative layers are decisive for aesthetic value of castings, therefore significant demands are raised towards such layers, e.g. pleasant durable colour, gloss, and smoothness. The work discusses the influence of the type of mechanical working applied to the surfaces of CuSn10 tin bronze castings on the quality and durability of a decorative coating. The scope of the work has included designing and manufacturing of cast samples of tin bronze, mechanical working of the surfaces in order to prepare them for applying coating layers,generating decorative layers as a result of chemical reactions, and the quality assessment and comparison of the obtained coating. Theassessment of thickness and continuity of the obtained decorative layers based on metallographic examinations has been presented.

  9. CONTINUOUS HORIZONTAL CASTING OF PIPE BRONZE BILLET

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2015-05-01

    Full Text Available An experimental and calculated thermal analysis of the continuous casting of bronze tube billets is developed. Calculated allowable thermal conditions of drawing for stable casting.

  10. New Research on Bronze Age Textile Production

    DEFF Research Database (Denmark)

    Andersson, Eva Birgitta; Mårtensson, Linda; Nosch, Marie-Louise Bech; Rahmstorf, Lorenz

    2008-01-01

    presentation of the results from the systematic tests with Bronze Age textile tools. results concerning mesurements of lenght and time consumed.......presentation of the results from the systematic tests with Bronze Age textile tools. results concerning mesurements of lenght and time consumed....

  11. The Bronze Age Smith as Individual

    DEFF Research Database (Denmark)

    Nørgaard, Heide Wrobel

    During 1550-1100 BC magnificent decorated bronze objects appear in grave and hoard finds in Northwest Europe. While investigating similarities in the decorative elements of bronze objects belonging to the female gender, it is possible to find traces of the production process. These distinctive fe...

  12. Population genomics of Bronze Age Eurasia

    DEFF Research Database (Denmark)

    Allentoft, Morten E.; Sikora, Martin; Sjögren, Karl-Göran;

    2015-01-01

    The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We...... structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a...... more recent onset of positive selection on lactose tolerance than previously thought....

  13. Population genomics of Bronze Age Eurasia.

    Science.gov (United States)

    Allentoft, Morten E; Sikora, Martin; Sjögren, Karl-Göran; Rasmussen, Simon; Rasmussen, Morten; Stenderup, Jesper; Damgaard, Peter B; Schroeder, Hannes; Ahlström, Torbjörn; Vinner, Lasse; Malaspinas, Anna-Sapfo; Margaryan, Ashot; Higham, Tom; Chivall, David; Lynnerup, Niels; Harvig, Lise; Baron, Justyna; Della Casa, Philippe; Dąbrowski, Paweł; Duffy, Paul R; Ebel, Alexander V; Epimakhov, Andrey; Frei, Karin; Furmanek, Mirosław; Gralak, Tomasz; Gromov, Andrey; Gronkiewicz, Stanisław; Grupe, Gisela; Hajdu, Tamás; Jarysz, Radosław; Khartanovich, Valeri; Khokhlov, Alexandr; Kiss, Viktória; Kolář, Jan; Kriiska, Aivar; Lasak, Irena; Longhi, Cristina; McGlynn, George; Merkevicius, Algimantas; Merkyte, Inga; Metspalu, Mait; Mkrtchyan, Ruzan; Moiseyev, Vyacheslav; Paja, László; Pálfi, György; Pokutta, Dalia; Pospieszny, Łukasz; Price, T Douglas; Saag, Lehti; Sablin, Mikhail; Shishlina, Natalia; Smrčka, Václav; Soenov, Vasilii I; Szeverényi, Vajk; Tóth, Gusztáv; Trifanova, Synaru V; Varul, Liivi; Vicze, Magdolna; Yepiskoposyan, Levon; Zhitenev, Vladislav; Orlando, Ludovic; Sicheritz-Pontén, Thomas; Brunak, Søren; Nielsen, Rasmus; Kristiansen, Kristian; Willerslev, Eske

    2015-06-11

    The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought. PMID:26062507

  14. The Bronze Age Smith as Individual

    OpenAIRE

    Nørgaard, Heide Wrobel

    2011-01-01

    During 1550-1100 BC magnificent decorated bronze objects appear in grave and hoard finds in Northwest Europe. While investigating similarities in the decorative elements of bronze objects belonging to the female gender, it is possible to find traces of the production process. These distinctive features can help to identify workshops and their sphere of influence. Sometimes these traces have the ability to give much more information than just indicate the crafting process of the object. Errors...

  15. Associação de Vibrio cholerae com o zooplâncton de águas estuárias da Baía de São Marcos/São Luis - MA, Brasil Association between Vibrio cholerae and zooplankton of estuaries of São Marcos Bay/São Luis - MA, Brazil

    OpenAIRE

    Eloisa da Graça do Rosario Gonçalves; Maria José Saraiva Lopes; Eurípedes Gomes de Oliveira; Ernesto Hofer

    2004-01-01

    Foi investigado, no período de outubro de 1997 a outubro de 1998, a possível associação de Vibrio cholerae com o zooplâncton dos estuários dos rios Anil e Bacanga, em São Luis - MA, Brasil, a presença da forma viável, mas não cultivável de Vibrio cholerae O1 e a correlação entre pH, salinidade e temperatura da água com a sobrevivência da bactéria. Amostras de zooplâncton foram coletadas em dois pontos fixos em cada estuário. O método clássico de isolamento e imunofluorescência direta foram em...

  16. Electrocatalytic activity and surface properties of tungsten bronzes

    International Nuclear Information System (INIS)

    The electrocatalytic activities of sodium tungsten bronzes, including high purity crystals, platinum doped crystals, and platinum plated crystals, have been measured for oxygen reduction in acid solution. In addition, a survey of the electrocatalytic activities and general electrochemical properties of other alkali tungsten bronzes, thalium tungsten bronze, and tungsten trioxide were investigated and compared to sodium tungsten bronze. All measurements were done on single crystals. Pure sodium tungsten bronzes and WO3 have a slight catalytic activity for oxygen reduction. The exchange current density is approximately 10-14 A/cm2. Doping the cubic sodium tungsten bronze with up to 800 ppM of platinum slightly increased the catalytic activity of the crystals, but the effect was noticeable only at very low current densities. Platinum preelectrolysis of the solution was shown to contaminate the crystal surface with significant amounts of platinum. For the platinum plated bronze crystals, no synergistic effect between the platinum and the bronze was observed for oxygen reduction. However, different platinum plating methods gave more than an order of magnitude difference in catalytic activity, with the same amount of platinum. The platinum was deposited on the bronze surface in different forms by the different plating methods. One possible form of highly dispersed platinum on a bronze surface is the formation of a platinum tungsten bronze, Pt/sub x/WO3. Hydrogen tungsten bronze is formed in the surface layers of all the bronzes at potentials below +0.2 V (NHE), and the reaction is completely reversible. One possible form of highly dispersed platinum on a bronze surface is the formation of a platinum tungsten bronze, Pt/sub x/WO3. Hydrogen tungsten bronze is formed in the surface layers of all the bronzes at potentials below +0.2 V (NHE), and the reaction is completely reversible

  17. Electrocatalytic activity and surface properties of tungsten bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Weber, M.F.

    1977-12-01

    The electrocatalytic activities of sodium tungsten bronzes, including high purity crystals, platinum doped crystals, and platinum plated crystals, have been measured for oxygen reduction in acid solution. In addition, a survey of the electrocatalytic activities and general electrochemical properties of other alkali tungsten bronzes, thalium tungsten bronze, and tungsten trioxide were investigated and compared to sodium tungsten bronze. All measurements were done on single crystals. Pure sodium tungsten bronzes and WO/sub 3/ have a slight catalytic activity for oxygen reduction. The exchange current density is approximately 10/sup -14/ A/cm/sup 2/. Doping the cubic sodium tungsten bronze with up to 800 ppM of platinum slightly increased the catalytic activity of the crystals, but the effect was noticeable only at very low current densities. Platinum preelectrolysis of the solution was shown to contaminate the crystal surface with significant amounts of platinum. For the platinum plated bronze crystals, no synergistic effect between the platinum and the bronze was observed for oxygen reduction. However, different platinum plating methods gave more than an order of magnitude difference in catalytic activity, with the same amount of platinum. The platinum was deposited on the bronze surface in different forms by the different plating methods. One possible form of highly dispersed platinum on a bronze surface is the formation of a platinum tungsten bronze, Pt/sub x/WO/sub 3/. Hydrogen tungsten bronze is formed in the surface layers of all the bronzes at potentials below +0.2 V (NHE), and the reaction is completely reversible. One possible form of highly dispersed platinum on a bronze surface is the formation of a platinum tungsten bronze, Pt/sub x/WO/sub 3/. Hydrogen tungsten bronze is formed in the surface layers of all the bronzes at potentials below +0.2 V (NHE), and the reaction is completely reversible.

  18. Effects of dispersed sulfides in bronze under line contact conditions

    Directory of Open Access Journals (Sweden)

    Tomohiro Sato

    2016-03-01

    Full Text Available A sintered bronze system is applied to plane bearings with some lubricants. A bronze-based, sulfide-dispersed Cu alloy was developed via sintering. Sulfides had some functions, reduction of friction resistance, preventing scoring and seizure. Effects of the developed sulfide-containing bronze were investigated using a journal-type testing apparatus in wet conditions; results indicate that the developed bronze may have some anti-scoring properties.

  19. Canção do Amor Demais: marco da música popular brasileira contemporânea Canção do Amor Demais [Song of Too Much Love]: a milestone in contemporary Brazilian popular music

    Directory of Open Access Journals (Sweden)

    Liliana Harb Bollos

    2010-12-01

    Full Text Available Discussão sobre a importância do LP Canção do Amor Demais dentro do panorama da cultura brasileira, mais do que do âmbito da música popular em si, a partir do texto de Vinícius de Moraes na contracapa do disco e da crítica de José da Veiga Oliveira. A fronteira existente entre o popular e erudito fica menos evidente neste disco, por conta do alto grau composicional das canções e pelos arranjos assinados por Jobim, tendo em vista que ali se deu a apresentação de João Gilberto em disco e da batida do violão que iria simbolizar a Bossa Nova.This article discusses the importance of the LP Canção do Amor Demais (Song of Too Much Love within the panorama of Brazilian culture, much more than simply within the area of popular music itself. As the a starting point, this discussion uses the LP's liner notes by Vinícius de Moraes and the critique by José da Veiga Oliveira to demonstrate that the existing border between popular classical music become less evident with this album. This is due to the high compositional quality of the songs and arrangements by Tom Jobim, the introduction of João Gilberto and the guitar rhythms that would come to symbolize bossa nova.

  20. Bismuth bronze from machu picchu, peru.

    Science.gov (United States)

    Gordon, R B; Rutledge, J W

    1984-02-10

    The decorative bronze handle of a tumi excavated at the Inca city of Machu Picchu, Peru, contains 18 percent bismuth and appears to be the first known example of the use of bismuth with tin to make bronze. The alloy is not embrittled by the bismuth because the bismuth-rich constituent does not penetrate the grain boundaries of the matrix phase. The use of bismuth facilitates the duplex casting process by which the tumi was made and forms an alloy of unusual color. PMID:17749940

  1. Acicular crystals of sodium tungsten bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Bamberger, C.E. (Chemistry Div., Oak Ridge National Lab., Oak Ridge, TN (United States)); Kopp, O.C. (Chemistry Div., Oak Ridge National Lab., Oak Ridge, TN (United States) Dept. of Geological Sciences, Univ. of Tennessee, Knoxville, TN (United States))

    1993-08-01

    The synthesis of sodium tungsten bronzes, Na[sub x]WO[sub 3], with emphasis on crystals with acicular morphology, has been examined experimentally. The acicular morphology is obtained for a range of compositions in which 0.15 [<=] x [<=] 0.28, and generally more than one crystal structure is present. At x [approx] 0.28 the tetragonal II phase predominates, whereas at x [approx] 0.15 an unknown structure is the major phase. Surprisingly, all the bronzes tested exhibited large solubilities in hot aqueous solutions of NH[sub 4]OH. (orig.)

  2. Panorama Acadêmico sobre Resíduos Sólidos: Análise da produção cientifica a partir do marco legal do setor

    Directory of Open Access Journals (Sweden)

    Layon Carlos Cezar

    2015-08-01

    Full Text Available Esse artigo objetiva analisar o panorama da produção científica nacional a respeito dos resíduos sólidos na área da administração, ciências contábeis, economia e turismo, a partir da sanção da Lei nº 12.305/2010 que instituiu a Política Nacional dos Resíduos Sólidos (PNRS. Acredita-se que os estudos obtiveram maior robustez a partir da criação da referida Lei que trouxe inúmeros desafios para os municípios e novos debates científicos para o setor. Para efetivação deste estudo, realizou-se pesquisa bibliográfica no portal eletrônico de indexação de artigos: SPELL. A análise foi realizada por meio de técnicas de bibliometria e metanálise. Os principais resultados apontam para baixa concentração de artigos embasados na PNRS, levando a pressupor, que a política pode estar enfrentando problemas quanto ao seu processo de implementação. A conclusiva deste estudo direciona-se para a visão de que novos debates científicos poderão ganhar maior solidez ao passo que a PNRS for implementada com eficiência ao longo do tempo.

  3. Teoria Geopolítica e interpretações do continente sul-americano: marco geopolítico regional e a formação da Unasul

    OpenAIRE

    Bragatti, Milton Carlos

    2016-01-01

    As dimensões continentais da América do Sul, suas tensões e arranjos geopolíticos, são objeto de adaptações e recontextualizações de conceitos-chave da “teoria geopolítica clássica”: na obra de vários autores, podemos encontrar claramente a utilização e releitura de formulações elaboradas por Ratzel, Mackinder, Haushofer e Mahan, entre outros. O objetivo deste trabalho é revisar uma breve bibliografia de estudos de Geopolítica sul-americana, especialmente trabalhos que apresentam “re-interpre...

  4. Plasmachemical preparation of lead-tungstate bronze

    Czech Academy of Sciences Publication Activity Database

    Brožek, Vlastimil; Janča, J.; Eliáš, M.

    Praha : MAXDORF,s.r.o, 2004, s. 13-14. ISBN 80-7345-032-1. [Joint Seminar Development in Material Science Research and Education/14th./. Lednice (CZ), 31.08.2004-03.09.2004] Institutional research plan: CEZ:AV0Z2043910 Keywords : tungsten bronzes, plasmachemical preparation, RF-discharge Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

  5. Copper and bronze coating with molybdenite

    International Nuclear Information System (INIS)

    The conditions were studied for producing qualitative bronze self-lubricating composite electrochemical coatings (SCEC). The copper composite coatings have been produced from sulfate electrolyte used for copper plating. The bronze SCEC have been obtained from a bath of the composition: tin dichloride-35, copper chloride-40, pyrophosphoric potassium-490. The problem of the optimal planning of Cu-MoS2 composite coatings characteristics has been considered. The matrix of the experiments planning is given, as well as the test results and numerical solution of coefficients of regression equations. The hardness of the bronze SCEC is affected most of all by the concentration and acidity of the suspension, and least of all - by the bath temperature. The friction coefficient of the self-lubricating coatings coupled with brass depends to a greater extent on the temperature and concentration of the suspension. The highest decrease of the friction coefficient can be expected at the minimum value of the abovesaid technological factors. The transient electric conductivity of the couple undergoing friction in air depends mainly on the cathode current density and concentration of dispersion phase in the electrolyte used for bronze plating. With the increase in the suspension concentration (and, therefore, in the amount of MoS2 inclusions into the coatings) the antifriction properties of the SCEC enhance. The dispersion addition increases the transient electric conductivity of the contact, however this does not prevent SCEC from being used in electrocommutation devices

  6. 75 FR 14257 - Pricing for Bronze Medals

    Science.gov (United States)

    2010-03-24

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE TREASURY United States Mint Pricing for Bronze Medals AGENCY: United States Mint, Department of the Treasury. ACTION: Notice. SUMMARY: The United States Mint is announcing the price of the 1\\5/16\\- inch...

  7. The Chalcolithic and the Bronze Age in the river Neiva Basin, NW of Portugal

    OpenAIRE

    Magalhães, Marisa Cardoso

    2016-01-01

    Relatório de estágio de mestrado em Arqueologia O presente relatório deseja expor os resultados da investigação sobre o Calcolítico e a Idade do Bronze da bacia do Neiva, desenvolvida durante o segundo ano de Mestrado em Arqueologia na Universidade do Minho. Relativamente a estes períodos cronológicos podemos destacar a diversidade de estratégias de povoamento, com tendências para ocupações de locais de menor altitude e mais próximas de vales. Estas comunidades que se estabelec...

  8. As estratégias de cooperação Sul-Sul nos marcos da política externa brasileira de 1993 a 2007 South-South cooperation strategies in Brazilian Foreign Policy from 1993 to 2007

    Directory of Open Access Journals (Sweden)

    Miriam Gomes Saraiva

    2007-12-01

    Full Text Available O objetivo do artigo é analisar as duas vertentes da cooperação sul-sul adotadas pela política externa brasileira entre 1993 e 2007. Por um lado, o artigo examina a política externa brasileira em face da América do Sul: o Mercosul e a cooperação sul-americana em termos mais gerais que, dentro do arco das atuações externas do país, é o tipo de cooperação sul-sul identificada como prioritária. Por outro lado, dedicará também algumas reflexões para a cooperação do Brasil com outros países considerados emergentes e system-affecting, em outros continentes, como é o caso da África do Sul, Índia, China e, em diferente medida, da Rússia.The aim of this article is to analyze the two approaches to South-South cooperation evident in Brazilian foreign policy between 1993 and 2007. On one hand the article examines Brazilian foreign policy towards South America. Specifically, cooperation with Mercosur members and South-American cooperation broadly conceptualized. The region is a foreign policy priority among its south-south cooperation activities. On the other hand, this paper reflects on Brazilian cooperation with other emerging and "system-affecting" countries that belong to other continents, such as South Africa, India and China, and to a certain extent, Russia.

  9. Morphometrics and Theriology. Homage to Marco Corti

    Directory of Open Access Journals (Sweden)

    Anna Loy

    2008-02-01

    Full Text Available Abstract This paper discusses the role of museum theriological collections in the context of twenty years of morphometric progresses. It also recalls twenty years of collaboration and friendship with Marco Corti, Italian theriologist and morphometrician, died on January 2007. The synthesis is addressed to the many young students that are picking up the baton and will likely contribute to the growth of the Italian school of morphometrics, to which Marco Corti dedicated most of his work at the University of Rome "La Sapienza". Riassunto Morfometria e teriologia. Omaggio a Marco Corti. Il lavoro discute il ruolo delle collezioni teriologiche alla luce di venti anni di progressi della morfometria. Esso rappresenta anche la sintesi di un’esperienza umana e professionale, avendo l’autore condiviso molte tappe della ‘rivoluzione morfometrica’ degli anni ottanta con molti dei suoi protagonisti, alcuni dei quali oggi non sono più con noi. In particolare Marco Corti, teriologo e morfometrista, scomparso nel 2007. La sintesi è anche dedicata ai molti giovani studenti e ricercatori che stanno contribuendo alla crescita della scuola italiana di morfometria, cui Marco Corti ha dedicato gli ultimi venti anni di insegnamento e ricerca all’Università di Roma "La Sapienza".

  10. Late Bronze Age hoard studied by PIXE

    International Nuclear Information System (INIS)

    The hoards of metallic objects belonging to the Late European Bronze Age can be interpreted differently depending on the type, number and composition of the artefacts. PIXE analysis has been performed in nine items from the Hoard of Freixanda in Portugal comprising four socket axes, a palstave axe, a ring, a chisel, a dagger, and a casting debris. Besides the composition of the main matrix elements, that is Cu and Sn, the amount of trace elements of interest like, As, Pb, Ni, and Ag has been determined using this ion beam technique. The high tin content alloy and the high purity of the metals from the Freixanda hoard are characteristic of the Portuguese and Spanish Late Bronze Age metallurgy, supporting the idea of a regional production.

  11. The thermal analysis and derivative bronzes cast to plaster moulds

    Directory of Open Access Journals (Sweden)

    B. Pisarek

    2009-07-01

    Full Text Available It plaster moulds gets casted the alloys of following metals: Al, Cu, Ag, Au in precise and artistic founding. The investigation of the crys-tallization of bronzes in hot plaster moulds the method of the thermal analysis and derivative (TDA was not realized out so far. Probe TDAg and tripod enabling the execution of measurements on inductive casting machine INDUTHERM-VC 500D were designed for this technology especially. It was confirmed that one the method TDA can identify the crystallization process of the bronze in hot plaster moulds. The investigations of the superficial distribution of the concentration of elements in the microstructure of the studied grades of the bronze on X-ray microanalizer were conducted. It results that they be subject to in bronze CuSn10-C (B10 and the CuSn5Zn5Pb5-C (B555 of strong microsegregation from conducted investigations: Pb, Sn and Sb. The single separates of intermetallic phase κ was identified in the bronze B10 rich first of all in Zn, Sn, Sb and Fe, and two intermetallic phase, one rich were identified in the bronze B555 first of all in Zn, Sb, (Nor, Fe and second rich in Sn, Sb, (Nor, Fe. The most homogeneous microstructure from the bronze CuAl10Fe5Ni5-C (BA1055 is characterizes among the studied grades of the bronze in the cast state.

  12. 77 FR 14600 - Pricing for 2012 Kennedy Half-Dollar Bags and Rolls, Bronze Medals, the First Spouse Bronze Medal...

    Science.gov (United States)

    2012-03-12

    ... United States Mint Pricing for 2012 Kennedy Half-Dollar Bags and Rolls, Bronze Medals, the First Spouse.... SUMMARY: The United States Mint is announcing 2012 pricing for Kennedy Half-Dollar bags and rolls, bronze..., Associate Director for Sales and Marketing; United States Mint; 801 9th Street NW., Washington, DC 20220;...

  13. Late Bronze Age Hoard studied by PIXE

    OpenAIRE

    Gutiérrez Neira, P. C.; Zucchiatti, A.; Montero-Ruiz, I.; Vilaça, R.; Bottaini, C.; Gener, M.; Climent-Font, A.

    2011-01-01

    The hoards of metallic objects belonging to the Late European Bronze Age can be interpreted differently depending on the type, number and composition of the artefacts. PIXE analysis has been performed in nine items from the Hoard of Freixanda in Portugal comprising 4 socket axes, a palstave axe, a ring, a chisel, a dagger, and a casting debris. Besides the composition of the main matrix elements, that is Cu and Sn, the amount of trace elements of interest like, As, Pb, Ni and A...

  14. Gold and Silver Inlaid Bronze Sheep

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gold and silver inlaying is a metal processing technique popular during the Spring and Autumn Period (770-476 B. C.) and the Warring States Period (475-221 B. C.). Patterns on the surface of the bronze figure are chiselled out and gold and silver threads (which can be as thin as hair) are inlaid. Finally the whole figure is filed and polished resulting in a splendid artistic work highlighting the different colours of the three different kinds of metal. The artifact shown here was unearthed from Ningxia'...

  15. Marco Polo Dances Back to China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The national theater’s first dance drama premieres in late December The first original dance drama of China’s National Center for the Performing Arts (NCPA) Marco Polo will debut at the theater on December 22, a move to continue the tradition of launching excellent stage works to celebrate the theater’s anniversary.This December marks the theater’s third birthday.

  16. Terra sonâmbula e O outro pé da sereia: dois marcos na obra do romancista Mia Couto = Terra sonâmbula and O outro pé da sereia: two important novels in the work of Mia Couto

    OpenAIRE

    Ventura, Susana Ramos

    2013-01-01

    O presente ensaio tece considerações sobre a obra do escritor moçambicano Mia Couto, com ênfase para as questões tratadas em dois de seus romances mais representativos: Terra sonâmbula (1992) e O outro pé da sereia (2006). O ensaio mostra temas recorrentes nos romances do autor e aponta para a abertura de novos caminhos a partir da obra de 2006. Num momento em que o escritor moçambicano começa a ficar mais conhecido que a própria obra, espera-se colaborar para uma reflexão aprofundada da obra...

  17. Russian meteorite Bronze Age (rock record)

    CERN Document Server

    Vodolazhskaya, Larisa

    2013-01-01

    This paper presents the results of a study of petroglyphs found in the quartzite grotto near the Skelnovsky small village in the Northern Black Sea in the South of Russia. The aim of the study was the analysis and interpretation of the Early Bronze Age petroglyphs using archaeoastronomical methods. The article presents a comparative analysis of Skelnovsky grotto ancient images and contemporary eyewitness accounts of the Sikhote-Alin meteorite fall and meteorite shower. Some petroglyphs were interpreted by us using ethnographic and folklore material. In this study, the magnetic declination for the geographical coordinates Skelnovsky farm was calculated, and the projection of the whole picture Skelnovskih petroglyphs on the topographical map of the area was built. The proposed location of the meteorite fall was determined with this projection. It is confirmed by satellite pictures, on which are the distinguishable terrain features, typical for the meteorite fall, are visible including the possible impact crater...

  18. Stamps of New China Eastern Zhou Dynasty Bronzes

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The State Postal Bureau’s latest set of special stamps for 2003 features Eastern Zhou Dynasty (770-256 B,C.) bronzes. This eight-stamp set is the third to feature this type of relic; a set issued in 1964 depicted bronzes from the Yin Dynasty (14th-11th century}, and one featuring Western Zhou Dynasty (11th century-771 B.C.) bronzes was released in 1982.The Eastern Zhou Dynasty followed the Western, and during this period, bronze vessel casting developed remarkably. Artifacts from this period include sacrificial vessels, musical instruments, utensils, weapons and tools.One of these pieces, a rectangular tray decorated with tortoise and fish patterns, dates back to the late Spring and Autumn Period

  19. The Czech lands and Austria in the Bronze Age

    Czech Academy of Sciences Publication Activity Database

    Jiráň, Luboš; Salaš, M.; Krenn-Leeb, A.

    Oxford: Oxford University Press, 2013 - (Fokkens, H.; Harding, A.), s. 787-812 ISBN 978-0-19-957286-1 Institutional support: RVO:67985912 Keywords : Bronze Age * Bohemia * Moravia * Austria Subject RIV: AC - Archeology, Anthropology, Ethnology

  20. Reversibility of the lithium-vanadium bronze structure when cycled

    International Nuclear Information System (INIS)

    The positive electrodes of the lithium secondary current sources, manufactured on the basis of the Li1+x V3O8 lithium-vanadium bronze, obtained through the alcoxotechnology, are studied. It is established, that in proportion to the lithium introduction the initial crystalline bronze renders amorphous, remaining a single-phase one. Increase in the x-lithifying rate leads practically to decrease in the α-parameters and increase in the b- and c-parameters of the bronze crystal lattice, whereby these changes are quite reversible by cycling. The obvious degradation of the electrode electrical parameters is not connected with irreversible structural changes and may be explained by formation of passive films on the surface of the particles of the lithium-vanadium bronze

  1. Non-destructive analysis of archaeological bronzes by nuclear techniques

    International Nuclear Information System (INIS)

    This paper studies a method for overcoming the difficulty of corroded surfaces by means of nondestructive nuclear methods in the determination of the composition of archaeological bronzes. It consists of the combination of PIXE or XRF information with Gamma Ray Transmission (GRT) data. A wide range applicability of this combined method is established by comparison with profiles of concentrations along the bronzes' patina obtained by SEM-EDAX. (orig.)

  2. Preparation and evaluation of thin-film sodium tungsten bronzes

    Science.gov (United States)

    Kautz, H. E.; Fielder, W. L.; Singer, J.; Fordyce, J. S.

    1974-01-01

    Thin films of sodium tungsten bronze (NaxWO3) were investigated as reversible sodium ion electrodes for solid electrolytes. The films were made by electron beam evaporation of the three phases, W metal, Na2WO4, and WO3, followed by sintering. The substrates were sodium beta alumina disks and glass slides. X-ray diffraction analyses of the films showed that sintering in dry nitrogen with prior exposure to air lead to mixed phases. Sintering in vacuum with no air exposure produced tetragonal I bronze with a nominal composition of Na0.31WO3, single phase within the limits of X-ray diffraction detectability. The films were uniform and adherent on sodium beta alumina substrates. The ac and dc conductivities of the beta alumina were measured with the sodium tungsten bronze films as electrodes. These experiments indicated that the tetragonal I bronze electrodes were not completely reversible. This may have resulted from sodium ion blocking within the bronze film or at the bronze beta alumina interface. Methods for attempting to make more completely reversible electrodes are suggested.

  3. Electrochemical testing of laser treated bronze surface

    Energy Technology Data Exchange (ETDEWEB)

    Yilbas, B.S., E-mail: bsyilbas@kfupm.edu.sa [Dept. of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261 (Saudi Arabia); Toor, Ihsan-ul-Haq; Malik, Jahanzaib; Patel, F. [Dept. of Mechanical Engineering, King Fahd University of Petroleum and Minerals (KFUPM), Dhahran 31261 (Saudi Arabia); Karatas, C. [Engineering Faculty, Hacettepe University, Ankara (Turkey)

    2013-06-25

    Highlights: ► Laser treated surface is free from asperities. ► Laser treated layer extends uniformly below the surface with a thickness in the order of 40 μm. ► Presence of Cu{sub 3}N nitrides is evident from X-ray diffractogram. ► Dendritic structure is formed below the surface due to relatively slower cooling rates as compared to that at the surface. ► The corrosion current density for the laser treated surface is much less than that of the as-received surface. -- Abstract: Electrochemical testing of laser treated bronze surface is carried out and corrosion resistance of the surface is assessed. Morphological and metallurgical changes in the laser treated layer are examined using scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction. The pit sites formed at the surface are analyzed using scanning electron microscope. It is found that laser treatment improves the corrosion resistance of the treated surface. Fine grains are formed in the surface region of the laser treated layer, which are attributed to the large cooling rates from the surface.

  4. Study of patina formation on bronze specimens

    International Nuclear Information System (INIS)

    In this study, bronze samples (94.059% Cu; 0.023% Zn; 0.077% Pb and 5.801% Sn, w/w) were exposed for 8 months to a marine atmosphere (splash zone) at Barra of Tijuca Beach, Rio de Janeiro. X-ray diffraction analysis (XRD) was used to identify the composition of the corrosion products formed on the samples. The electrochemical properties were analyzed using potential and electrochemical impedance measurements. These analyses and measurements were obtained from periodically removed samples, and compared to those exposed to laboratory tests (total and alternating immersion) in 10-2 mol L-1 NaCl solution. The corrosion potential results, allied to XRD analysis, showed that the chemical nature of the films obtained on the surface of the field test samples was very similar to that obtained in the alternating immersion test. The main products identified were cuprite and atacamite. However, the film formed during the total immersion (TI) test was primarily composed of cuprite with nantokite traces, which was not observed in either the field or in alternating tests. The electrochemical impedance measurements obtained in laboratory and field test samples showed the formation of films with a porous structure. The thermodynamic evaluation was also consistent with the corrosion products formed.

  5. Evaluation of Bio-field Treatment on Physical and Structural Properties of Bronze Powder

    OpenAIRE

    Mahendra Kumar Trivedi; Gopal Nayak; Rama Mohan Tallapragada

    2015-01-01

    Bronze, a copper-tin alloy, widely utilizing in manufacturing of gears, bearing, and packing technologies due to its versatile physical, mechanical, and chemical properties. The aim of the present work was to evaluate the effect of bio-field treatment on physical and structural properties of bronze powder. Bronze powder was divided into two samples, one served as control and the other sample was received bio-field treatment. Control and treated bronze samples were characterized using x-ray di...

  6. Evaluation of Biofield Treatment on Physical and Structural Properties of Bronze Powder

    OpenAIRE

    Trivedi, Mahendra; Nayak, Gopal

    2015-01-01

    Bronze, a copper-tin alloy, widely utilizing in manufacturing of gears, bearing, and packing technologies due to its versatile physical, mechanical, and chemical properties. The aim of the present work was to evaluate the effect of biofield treatment on physical and structural properties of bronze powder. Bronze powder was divided into two samples, one served as control and the other sample was received biofield treatment. Control and treated bronze samples were characterized using x-ray diff...

  7. 76 FR 72369 - Safety Zone; Marco Island Marriott Charity Fireworks Display, Gulf of Mexico, Marco Island, FL

    Science.gov (United States)

    2011-11-23

    ... Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public meeting. But you may... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Marco Island Marriott Charity Fireworks Display, Gulf of Mexico, Marco Island, FL AGENCY: Coast Guard, DHS. ACTION: Notice of proposed...

  8. Giuseppe Girimonti Greco, Sabrina Martina, Marco Piazza (eds., Proust e gli oggetti

    Directory of Open Access Journals (Sweden)

    Elena Porciani

    2013-05-01

    Full Text Available Treni, ascensori, biciclette, telefoni, telegrafi, lampade, lenti, ma anche fiori, frutti, biscotti, gioielli, porcellane, fotografie, dipinti, libri, persino le guance di Albertine... Questi oggetti e altri sono presi in esame dai venticinque saggi che compongono il ricco volume curato da Giuseppe Girimonti Greco, Sabrina Martina e Marco Piazza, dei quali più della metà è in lingua francese, a sancire quello spirito internazionale dell’operazione cui contribuisce anche la variegata provenienza degli autori: non solo italiani e francesi, ma anche studiosi originari di altri paesi europei e asiatici.

  9. Prompt gamma-ray analysis of archaeological bronze

    International Nuclear Information System (INIS)

    Prompt γ-ray analysis using the internal monostandard method was applied to voluminous archaeological bronze mirrors produced in ancient China. Sn/Cu content ratios were determined nondestructively by this method. Furthermore, Au/Cu, As/Cu, and Sb/Cu content ratios were determined by means of measuring decay γ-rays emitted from radioactive nuclides produced within samples via (n,γ) reactions. It is clear that the Sn/Cu content ratios in bronze mirrors produced in the Sung era is smaller than in ones produced in between the Han and the Tung era. (author)

  10. Chisels in the italian Bronze Age: technological and typological aspects

    OpenAIRE

    Speciale, Claudia; Zanini, Alessandro

    2010-01-01

    Bronze chisels are tools used “à percussion posée”; this means they need a minimum length and some functional parts (tang, body, blade); they could have a handle of perishable material and they were used with a hammer to work wood, bronze and other materials. Chisels can be classified following their functional parts; the first element is the shape (rod or socketed chisel); the second one is body section; the third one is tang section. Chronology and distribution of every type were identified...

  11. Archaeological investigations of the Bronze Age village of Bagnara di Romagna (RA

    Directory of Open Access Journals (Sweden)

    Maurizio Cattani

    2014-12-01

    Full Text Available This paper summarizes the results of researches carried out in the area next to the modern village of Bagnara di Romagna (RA, where several evidences related to a Bronze Age settlement have been collected. Recently test trenches and surface collections allowed to retrieve bronze and ceramics dating from the Middle Bronze Age (phase BM2 to the Recent Bronze Age (phase BR2. The analysis of landscape and the palaeoenvironmental reconstruction complete the outline of the region of Imola, Faenza and Lugo during the Bronze Age where are well known the ancient settlements of Solarolo, via Ordiere, Monte Castellaccio end S. Giuliano di Toscanella.

  12. Pantani di Marco Martinelli: una narrazione polifonica

    Directory of Open Access Journals (Sweden)

    Franco Nasi

    2014-05-01

    Full Text Available In questo articolo si analizza il testo drammaturgico Pantani di Marco Martinelli, una veglia epica teatrale di uno dei più noti eroi dello sport italiano degli ultimi anni. Il dramma rilegge anche la storia di Pantani e ricostruisce gli strani avvenimenti che portarono alla sospensione, alla estromissione del ciclista dal Giro d’Italia nel 1999, e in seguito alla sua profonda crisi psicologica e tragica morte in solitudine in un hotel, a soli 34 anni. Oltre alle modalità proprie della veglia rituale, il dramma utilizza anche i metodi del processo giudiziario, e offre testimonianze dettagliate che conducono a una riflessione critica sulla società italiana negli anni del potere politico di Berlusconi e della sua filosofia del consumismo. I tre diversi generi della retorica classica (epidittico, giudiziario e deliberativo si mescolano in questa complessa tessitura teatrale. Coniugando informazioni (processo e rito (veglia, Martinelli riesce a fondere la tragedia greca (forma mimetica e corale e il moderno teatro di narrazione (forma diegetica monologante. Combinando assieme scene intensamente drammatiche, ricordi di imprese sportive epiche, passaggi giocosi e parodici, e giustapponendo vari stili e registri (giornalistico, lirico, parodico, elegiaco, Martinelli crea momenti di forte “straniamento” e sorpresa, e rende particolarmente efficace il rito funebre, la ricostruzione storica della tragica vicenda di Pantani e la critica all’ideologia che ha dominato l’Italia negli anni di Berlusconi. 

  13. Origin of the mysterious Yin-Shang bronzes in China indicated by lead isotopes

    Science.gov (United States)

    Sun, Wei-Dong; Zhang, Li-Peng; Guo, Jia; Li, Cong-Ying; Jiang, Yu-Hang; Zartman, Robert E.; Zhang, Zhao-Feng

    2016-03-01

    Fine Yin-Shang bronzes containing lead with puzzlingly highly radiogenic isotopic compositions appeared suddenly in the alluvial plain of the Yellow River around 1400 BC. The Tongkuangyu copper deposit in central China is known to have lead isotopic compositions even more radiogenic and scattered than those of the Yin-Shang bronzes. Most of the Yin-Shang bronzes are tin-copper alloys with high lead contents. The low lead and tin concentrations, together with the less radiogenic lead isotopes of bronzes in an ancient smelting site nearby, however, exclude Tongkuangyu as the sole supplier of the Yin-Shang bronzes. Interestingly, tin ingots/prills and bronzes found in Africa also have highly radiogenic lead isotopes, but it remains mysterious as to how such African bronzes may have been transported to China. Nevertheless, these African bronzes are the only bronzes outside China so far reported that have lead isotopes similar to those of the Yin-Shang bronzes. All these radiogenic lead isotopes plot along ~2.0–2.5 Ga isochron lines, implying that deposits around Archean cratons are the most likely candidates for the sources. African cratons along the Nile and even micro-cratons in the Sahara desert may have similar lead signatures. These places were probably accessible by ancient civilizations, and thus are the most favorable suppliers of the bronzes.

  14. Final Critical Habitat for the San Marcos salamander (Eurycea nana)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for San Marcos salamander (Eurycea nana) occur based on the description provided in...

  15. Kas doktorikooli lõpetajatest saavad doktorid? / Marco Kirm

    Index Scriptorium Estoniae

    Kirm, Marco, 1965-

    2008-01-01

    Materjaliteaduse ja materjalide tehnoloogia doktorikool on TÜ Füüsika-keemiateaduskonna ja Füüsika Instituudi juurde loodud institutsioon. Vastab Tartu Ülikooli Füüsika Instituudi teadusdirektor Marco Kirm

  16. Panetta Awarded Bronze Star for Afghanistan Intel Mission

    OpenAIRE

    Naval Postgraduate School Public Affairs Office

    2008-01-01

    Fellow officers in full dress uniform, family and friends ringed the room in rapt attention as Naval Reserve Lt. James Panetta was awarded the Bronze Star Medal by Naval Postgraduate School President Daniel Oliver in a special ceremony in the President's Conference Room, Dec. 9.

  17. Lithium intercalation in perovskite and hexagonal tungsten bronze derivatives

    International Nuclear Information System (INIS)

    Lithium has been intercalated chemically and electrochemically in LnNb3O9 (Ln = La,Nd) perovskite-type phases and LiW3O9F which can be considered as a hexagonal tungsten bronze derivative. The crystallographic formula of the LnNb3O9 starting material is described

  18. Corrosion behavior of leaded-bronze alloys in sea water

    Energy Technology Data Exchange (ETDEWEB)

    Zohdy, K.M., E-mail: khalzohdy@yahoo.com [Higher Technological Institute, 10" t" h of Ramadan City (Egypt); Sadawy, M.M. [Mining and Petroleum Engineering Department, Al-Azhar University, Nasr City, Cairo 11371 (Egypt); Ghanem, M. [Industrial Education, Suez University (Egypt)

    2014-10-15

    The corrosion behavior of leaded-bronze alloys (Cu–5Sn–5Zn–5Pb, Cu–8Sn–8Zn–8Pb and Cu–10Sn–10Zn–10Pb) in sea water was investigated using weight loss method, open-circuit potential measurements (OCP), polarization techniques and electrochemical impedance spectroscopy (EIS). The nature and morphology of the corrosion products were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the corrosion resistance decreases with decreasing copper content. The XRD indicated that the composition of patina depends on the concentration of Cu, Sn, Zn and Pb in each alloy. - Highlights: • The corrosion potential of leaded bronze shifts to more noble potential. • The corrosion resistance increases with increasing amount of copper content in leaded bronze alloys. • The patina formed on Cu–5Sn–5Zn–5Pb is more uniform and protective than other alloys. • The composition of patina formed on leaded bronze depends on the concentration of Cu, Sn, Zn and Pb in the alloy.

  19. Electrodeposited nanocrystalline bronze alloys as replacement for Ni

    NARCIS (Netherlands)

    Hovestad, A.; Tacken, R.A.; Mannetje, H.H.'t

    2008-01-01

    Nanocrystalline white-bronze, CuSn, electroplating was investigated as alternative to Ni plating as undercoat for noble metals in jewellery applications. A strongly acidic plating bath was developed with an organic additive to suppress hydrogen evolution and obtain bright coatings. Polarization curv

  20. Corrosion behavior of leaded-bronze alloys in sea water

    International Nuclear Information System (INIS)

    The corrosion behavior of leaded-bronze alloys (Cu–5Sn–5Zn–5Pb, Cu–8Sn–8Zn–8Pb and Cu–10Sn–10Zn–10Pb) in sea water was investigated using weight loss method, open-circuit potential measurements (OCP), polarization techniques and electrochemical impedance spectroscopy (EIS). The nature and morphology of the corrosion products were investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results showed that the corrosion resistance decreases with decreasing copper content. The XRD indicated that the composition of patina depends on the concentration of Cu, Sn, Zn and Pb in each alloy. - Highlights: • The corrosion potential of leaded bronze shifts to more noble potential. • The corrosion resistance increases with increasing amount of copper content in leaded bronze alloys. • The patina formed on Cu–5Sn–5Zn–5Pb is more uniform and protective than other alloys. • The composition of patina formed on leaded bronze depends on the concentration of Cu, Sn, Zn and Pb in the alloy

  1. Reporting Casting Bronze Plaque Becomes Advisers Class Project

    Science.gov (United States)

    Ross, Charlie

    1977-01-01

    Describes an advisers' class project (at the University of Oklahoma) which consisted of reporting on the casting of a bronze plaque bearing the names of the first school newspaper, "The Students Gazette," and its editor, Samuel M. Fox, for presentation in Philadelphia to commemorate scholastic journalism's Bicentennial. (MB)

  2. Neutron scattering material analysis of Bronze Age metal artefacts

    International Nuclear Information System (INIS)

    Non-destructive characterization of bronze artefacts from archaeological finds of the 'Terramare' dwellings near Modena, Italy, was carried out by time-of-flight neutron scattering at the ISIS spallation neutron source of the Rutherford Appleton Laboratory, UK. This provides information on ancient metal technology and its development through the Bronze Age in that region. Six pieces from three different classes as to use and manufacture, from the Middle to Late Bronze Age, were investigated on the ROTAX and GEM beam lines at ISIS, providing a comparison between results from the two instruments. A comparison is also made with three axes of the same area of provenance (Emilia, Terramare culture) from the Early, Middle and Late Bronze Age respectively, analysed previously. Data collected provide stable refinements of the phase fractions and lattice parameters by the Rietveld method, allowing determination of Sn contents from the unit cell expansion due to the incorporation of Sn into the Cu-type α-phase. Notably, two of the objects exhibit a range of Sn contents in the bulk as is evident from broad diffraction peaks (4-8 and 10-14 wt% Sn), while the other four artefacts have more defined Sn contents of 8, 9, 10 and 14.5 wt% respectively. The higher Sn weight fractions are associated with the presence of pure unalloyed Cu, interestingly coexisting in one case with two bronze phases (α and the eutectoid δ). One sample shows the presence of 2-3 wt% Pb. Varying amounts of oxidation products such as cuprite were identified. Texture information extracted from the diffraction data provided some indications of different working treatments of the analysed objects

  3. Characterization of bronzes by abrasive stripping voltammetry and thin layer chromatography

    OpenAIRE

    Komorsky-Lovrić, Šebojka; Horvat, Alka J.M.; Ivanković, Danijela

    2006-01-01

    Corrosion potentials of five samples of bronzes having different compositions and the stripping peak potentials of their main components were determined by abrasive stripping voltammetry. Using thin-layer chromatography in combination with electrochemical dissolution of bronzes in the two electrode sampler, the ions of tin, copper, lead and nickel were detected as the products of electro-oxidation of bronzes. It is shown that the dissolution of tin is preferential at low potential differences...

  4. Indirect TL dating of bronze with their thermoluminescent clay/sand--cores

    International Nuclear Information System (INIS)

    The occasional presence of thermoluminescent clay/sand core remains in bronze raises a possibility of dating them with the TL technique. In the dating of several bronze objects excavated in Shanxi Province, some satisfactory results have been achieved with dating accuracy between 8% and 12%. Since the sample collection does no harm to the bronze body, the TL dating technique can be more widely applied in the dating and authenticity tests

  5. Rewriting the Central European Early Bronze Age Chronology: Evidence from Large-Scale Radiocarbon Dating.

    Directory of Open Access Journals (Sweden)

    Philipp W Stockhammer

    Full Text Available The transition from the Neolithic to the Early Bronze Age in Central Europe has often been considered as a supra-regional uniform process, which led to the growing mastery of the new bronze technology. Since the 1920s, archaeologists have divided the Early Bronze Age into two chronological phases (Bronze A1 and A2, which were also seen as stages of technical progress. On the basis of the early radiocarbon dates from the cemetery of Singen, southern Germany, the beginning of the Early Bronze Age in Central Europe was originally dated around 2300/2200 BC and the transition to more complex casting techniques (i.e., Bronze A2 around 2000 BC. On the basis of 140 newly radiocarbon dated human remains from Final Neolithic, Early and Middle Bronze Age cemeteries south of Augsburg (Bavaria and a re-dating of ten graves from the cemetery of Singen, we propose a significantly different dating range, which forces us to re-think the traditional relative and absolute chronologies as well as the narrative of technical development. We are now able to date the beginning of the Early Bronze Age to around 2150 BC and its end to around 1700 BC. Moreover, there is no transition between Bronze (Bz A1 and Bronze (Bz A2, but a complete overlap between the type objects of the two phases from 1900-1700 BC. We thus present a revised chronology of the assumed diagnostic type objects of the Early Bronze Age and recommend a radiocarbon-based view on the development of the material culture. Finally, we propose that the traditional phases Bz A1 and Bz A2 do not represent a chronological sequence, but regionally different social phenomena connected to the willingness of local actors to appropriate the new bronze technology.

  6. The study of bronze statuettes with the help of neutron-imaging techniques

    OpenAIRE

    Van Langh, R.; Lehmann, E; Hartmann, S.; Kaestner, A.; Scholten, F.

    2009-01-01

    Until recently fabrication techniques of Renaissance bronzes have been studied only with the naked eye, microscopically, videoscopically and with X-radiography. These techniques provide information on production techniques, yet much important detail remains unclear. As part of an interdisciplinary study of Renaissance bronzes undertaken by the Rijksmuseum Amsterdam, neutron-imaging techniques have been applied with the aim of obtaining a better understanding of bronze workmanship during the R...

  7. Production and properties of bronze based cellular materials

    International Nuclear Information System (INIS)

    For production of lightweight components, cellular materials offer attractive potential. Here, manufacturing of sintered bodies from bronze hollow spheres is described. The process starts with fabrication of hollow copper particles by cementation of Cu on iron particles. The still fragile Cu shells are consolidated by coating with Sn and subsequent gravity sintering. The resulting specimens exhibit a closed cell bronze structure with rather consistent morphology and cell wall thickness. The apparent density may range between 1.5 and 3.0 gcm-3 and can be controlled by variation of particle size and wall thickness. The mechanical behavior of the structures esp. during compressive loading is described and related to the microstructural parameters. (author)

  8. Quantitative multiphase analysis of archaeological bronzes by neutron diffraction

    CERN Document Server

    Siano, S; Celli, M; Pini, R; Salimbeni, R; Zoppi, M; Kockelmann, W A; Iozzo, M; Miccio, M; Moze, O

    2002-01-01

    In this paper, we report the first investigation on the potentials of neutron diffraction to characterize archaeological bronze artifacts. The preliminary feasibility of phase and structural analysis was demonstrated on standardised specimens with a typical bronze alloy composition. These were realised through different hardening and annealing cycles, simulating possible ancient working techniques. The Bragg peak widths that resulted were strictly dependent on the working treatment, thus providing an important analytical element to investigate ancient making techniques. The diagnostic criteria developed on the standardised specimens were then applied to study two Etruscan museum pieces. Quantitative multiphase analysis by Rietveld refinement of the diffraction patterns was successfully demonstrated. Furthermore, the analysis of patterns associated with different artifact elements also yielded evidence for some peculiar perspective of the neutron diffraction diagnostics in archeometric applications. (orig.)

  9. Pyroelectric properties of ceramic with tetragonal bronze tungsten structure

    International Nuclear Information System (INIS)

    Ceramics of the tetragonal tungsten bronze type of structure (Srx Ba1-x) Nb2 O6 (SBN), with x=0.25, x=0.50 e x=0.75, were synthesized by conventional methods. The dielectric and pyroelectric properties were analyzed with intention to determine the potential of the SBN ceramics for pyroelectric detection. The pyroelectric properties of these ceramic materials are pioneer results in this area. (author)

  10. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    OpenAIRE

    Napachat Tareelap; Kaysinee Sriraksasin; Nakorn Srisukhumbowornchai; Swieng Thuanboon; Choochat Nitipanyawong

    2014-01-01

    Due to the failure of manganese aluminium bronze (MAB) propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium...

  11. The Development of Iron Technology in the Mediterranean Bronze Age

    OpenAIRE

    Leek, Rodney Thomas

    2014-01-01

    In the eastern Mediterranean region in the Bronze Age there were a number of elite controlled, complex societies that through cultural activities and trade and international agreements, participated in a regional exchange economy. In the transition to Iron Age there was a confusing period with wars, migrations and the collapse of most of the elite societies,. At this time, iron technology had already spread to some parts of the region. When the regional economy collapsed in c. 1200 BC it crea...

  12. Tamil Chola Bronzes and Swamimalai Legacy: Metal Sources and Archaeotechnology

    Science.gov (United States)

    Srinivasan, Sharada

    2016-05-01

    This review explores the great copper alloy image casting traditions of southern India from archaeometallurgical and ethnometallurgical perspectives. The usefulness of lead isotope ratio and compositional analysis in the finger-printing and art historical study of more than 130 early historic, Pallava, Chola, later Chola, and Vijayanagara sculptures (fifth-eighteenth centuries) is highlighted, including Nataraja, Buddha, Parvati, and Rama images made of copper, leaded bronze, brass, and gilt copper. Image casting traditions at Swamimalai in Tamil Nadu are compared with artistic treatises and with the technical examination of medieval bronzes, throwing light on continuities and changes in foundry practices. Western Indian sources could be pinpointed for a couple of medieval images from lead isotope analysis. Slag and archaeometallurgical investigations suggest the exploitation of some copper and lead-silver sources in the Andhra and Karnataka regions in the early historic Satavahana period and point to probable copper sources for the medieval images in Karnataka, Tamil Nadu, and Andhra Pradesh. The general lower iron content in southern Indian bronzes perhaps renders the proximal copper-magnetite reserves of Seruvila in Sri Lanka as a less likely source. Given the lack of lead deposits in Sri Lanka, however, the match of the lead isotope signatures of a well-known Ceylonese Buddhist Tara in British Museum with a Buddha image from Nagapattinam in Tamil Nadu may underscore ties between the island nation and the southern Indian Tamil regions.

  13. Portable EDXRF investigation of the patinas on the Riace Bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Buccolieri, Giovanni, E-mail: giovanni.buccolieri@unisalento.it [Università del Salento, Dipartimento di Matematica e Fisica, via Arnesano, 73100 Lecce (Italy); Buccolieri, Alessandro, E-mail: alessandro.buccolieri@unisalento.it [Università del Salento, Dipartimento di Scienze e Tecnologie Biologiche e Ambientali, via Monteroni, 73100 Lecce (Italy); Donati, Paola, E-mail: paola.donati@beniculturali.it [Istituto Superiore per la Conservazione e il Restauro, via di San Michele n. 23, 00153 Roma (Italy); Marabelli, Maurizio, E-mail: maurizio.marabelli@libero.it [Istituto Superiore per la Conservazione e il Restauro, via di San Michele n. 23, 00153 Roma (Italy); Castellano, Alfredo, E-mail: alfredo.castellano@unisalento.it [Università del Salento, Dipartimento di Matematica e Fisica, via Arnesano, 73100 Lecce (Italy)

    2015-01-15

    This paper summarizes the experimental results concerning the Energy Dispersive X-ray Fluorescence (EDXRF) analysis of patinas on two Riace Bronzes, kept in the National Archaeological Museum of Reggio Calabria (Calabria, Southern Italy). The two large Greek sculptures, famous nude bearded warriors both dated in the fifth century BC, are without a doubt, two masterpieces of inestimable historic and artistic value. EDXRF survey had the aim to determinate the chemical composition of the surface of these two bronze statues and to discriminate their different patinas. In particular, the concentration of sulphur, chlorine, tin, manganese, iron, copper, zinc and lead was determined by using a portable apparatus. Multivariate statistical analysis was carried out in order to identify possible correlations and/or differences of elemental composition among the patinas of these two statues. The information obtained made it possible to improve knowledge about the patinas of the Riace Bronzes, and this may help further studies and subsequent methods of restoration and/or of preservation of the two celebrated Greek sculptures.

  14. Portable EDXRF investigation of the patinas on the Riace Bronzes

    International Nuclear Information System (INIS)

    This paper summarizes the experimental results concerning the Energy Dispersive X-ray Fluorescence (EDXRF) analysis of patinas on two Riace Bronzes, kept in the National Archaeological Museum of Reggio Calabria (Calabria, Southern Italy). The two large Greek sculptures, famous nude bearded warriors both dated in the fifth century BC, are without a doubt, two masterpieces of inestimable historic and artistic value. EDXRF survey had the aim to determinate the chemical composition of the surface of these two bronze statues and to discriminate their different patinas. In particular, the concentration of sulphur, chlorine, tin, manganese, iron, copper, zinc and lead was determined by using a portable apparatus. Multivariate statistical analysis was carried out in order to identify possible correlations and/or differences of elemental composition among the patinas of these two statues. The information obtained made it possible to improve knowledge about the patinas of the Riace Bronzes, and this may help further studies and subsequent methods of restoration and/or of preservation of the two celebrated Greek sculptures

  15. Model of Cu-Al-Fe-Ni Bronze Crystallization

    Directory of Open Access Journals (Sweden)

    B. P. Pisarek

    2013-07-01

    Full Text Available According to the analysis of the current state of the knowledge shows that there is little information on the process of phase transformations that occur during the cooling Cu-Al-Fe-Ni hypo-eutectoid bronzes with additions of Cr, Mo and/or W, made additions individually or together, for the determination of: the type of crystallizing phases, crystallizing phases, order and place of their nucleation. On the basis of recorded using thermal and derivative analysis of thermal effects phases crystallization or their systems, analysis of the microstructure formed during crystallization - observed on the metallographic specimen casting ATD10-PŁ probe, analysis of the existing phase equilibrium diagrams forming elements tested Cu-Al-Fe-Ni bronze, with additions of Cr, Mo, W and/or Si developed an original model of crystallization and phase transformation in the solid state, the casting of high quality Cu-Al-Fe-Ni bronze comprising: crystallizing type phase, crystallizing phase sequence, place of nucleation.

  16. Ley marco de aseguramiento universal en salud, bajo la lupa

    OpenAIRE

    Leoncio Díaz; Julio Vargas

    2009-01-01

    La Ley Marco de Aseguramiento Universal en Salud, concebida en el marco del modelo neoliberal conservador, excluyente y polarizante, fue aprobada en circunstancias en la que persisten grandes contrastes entre sistemas de salud. Por un lado, los países que mantienen subsistemas inconexos y privatizados y, por otro, los que unificados y bajo la responsabilidad del Estado, garantizan a todos el acceso integral, gratuito y de calidad a los servicios de salud. En América y el Caribe, existen paíse...

  17. Ser gestante soropositivo para o Vírus da Imunodeficiência Humana: uma leitura à luz do Interacionismo Simbólico Ser gestante seropositiva para el Virus de la inmunodeficiencia humana-HIV: una lectura bajo el marco teórico del Interaccionismo Simbólico Being pregnant seropositive and having acquired the human immunodeficiency Virus (HIV: a theoretical interpretation under the Symbolic Interactionism

    Directory of Open Access Journals (Sweden)

    Edilene Lins de Moura

    2010-04-01

    Full Text Available OBJETIVO: Descrever o contexto do cotidiano vivido por mulheres grávidas soropositivas para o Vírus da Imunodeficiência Humana (HIV, com enfoque na experiência de tornar-se grávida e assumir a gravidez. MÉTODOS: Os dados foram coletados por meio de entrevista gravada, com 14 gestantes sabidamente soropositivas para o HIV, que vivenciavam o terceiro trimestre de gravidez. O estudo fez uma leitura de dados brutos sobre expectativas e ações de gestantes soropositivas para o HIV, à luz do Interacionismo Simbólico. RESULTADOS: um dos aspectos encontrados mostrou que as mulheres HIV positivo assumem a gravidez, ainda que esta seja inesperada. CONCLUSÕES: os dados são um alerta para os profissionais de enfermagem que devem promover ações educativas para atender às demandas dessa mulher.OBJETIVO: Describir el contexto cotidiano vivido por mujeres embarazadas y seropositivas para el virus de la inmunodeficiencia humana (HIV, con enfoque en la experiencia de estar embarazada y aceptar ese estado. MÉTODOS: Los datos fueron recolectados por medio de entrevista grabada, con 14 gestantes sabidamente seropositivas para el HIV, que se encontraban en el tercer trimestre de embarazo. El estudio hizo una lectura de los datos brutos sobre expectativas y acciones de las gestantes seropositivas para el HIV, bajo el marco teórico del Interaccionismo Simbólico. RESULTADOS: Uno de los aspectos encontrados mostró que las mujeres infectadas con Sida aceptan el embarazo, inclusive cuando ocurre inesperadamente. CONCLUSIONES: Los datos sirven de para los profesionales de enfermería para que promuevan acciones educativas que atiendan las necesidades de esas mujeres.OBJECTIVE: To describe the context of everyday life experienced by pregnant women seropositive for human immunodeficiency virus (HIV, focusing on the experience of becoming pregnant and accepting that condition. METHODS: Data were collected recording interviews with 14 pregnant women known to

  18. The Philippine Press after Marcos: Restored Freedoms and New Problems.

    Science.gov (United States)

    Guimary, Donald L.

    With the overthrow of Ferdinand Marcos from his 20-year rule of the Philippines, the news media regained its freedom and its voice, and now faces a new set of problems: low circulation, questionable ethical standards of reporters and their lack of experience, and ominous indications from the Corazon Aquino government that the administration might…

  19. MarcoPolo Narrows the Search for Useful Classroom Materials.

    Science.gov (United States)

    Haller, Peter

    2001-01-01

    Addresses the issue of how teachers can conduct more efficient Internet searches in order to find sites that are unbiased, reliable, and accurate. Presents the MarcoPolo Project, a partnership among seven leading educational institutions, as a service that provides teachers with credible content through an easy-to-use Web interface. (NB)

  20. The moessbauer spectroscopy study of an ancient bronze mirror without sampling

    International Nuclear Information System (INIS)

    The Moessbauer spectra of 119Sn for a bronze mirror of the Han Dynasty are described. A method of measuring Moessbauer spectrum without sampling is established. For the sake of contrast, both the spectra of transmission and of γ-ray scattering were measured. The results show that on the surface of the bronze mirror tin is in the state of Sn4+ oxide

  1. Metallography and microstructure interpretation of some archaeological tin bronze vessels from Iran

    International Nuclear Information System (INIS)

    Archaeological excavations in western Iran have recently revealed a significant Luristan Bronzes collection from Sangtarashan archaeological site. The site and its bronze collection are dated to Iron Age II/III of western Iran (10th–7th century BC) according to archaeological research. Alloy composition, microstructure and manufacturing technique of some sheet metal vessels are determined to reveal metallurgical processes in western Iran in the first millennium BC. Experimental analyses were carried out using Scanning Electron Microscopy–Energy Dispersive X-ray Spectroscopy and Optical Microscopy/Metallography methods. The results allowed reconstructing the manufacturing process of bronze vessels in Luristan. It proved that the samples have been manufactured with a binary copper–tin alloy with a variable tin content that may relates to the application of an uncontrolled procedure to make bronze alloy (e.g. co-smelting or cementation). The presence of elongated copper sulphide inclusions showed probable use of copper sulphide ores for metal production and smelting. Based on metallographic studies, a cycle of cold working and annealing was used to shape the bronze vessels. - Highlights: • Sangtarashan vessels are made by variable Cu-Sn alloys with some impurities. • Various compositions occurred due to applying uncontrolled smelting methods. • The microstructure represents thermo-mechanical process to shape bronze vessels. • In one case, the annealing didn’t remove the eutectoid remaining from casting. • The characteristics of the bronzes are similar to other Iron Age Luristan Bronzes

  2. Abrasive wear of BA1055 bronze with additives of Si, Cr, Mo and/or W

    Directory of Open Access Journals (Sweden)

    B. P. Pisarek

    2008-10-01

    Full Text Available Aluminium bronzes belong to the high-grade constructional materials applied on the put under strongly load pieces of machines, aboutgood sliding, resistant properties on corrosion both in the cast state how and after the thermal processing. It moves to them Cr and Si in the aim of the improvement of their usable proprieties. The additions Mo and/or W were not applied so far. It was worked out therefore the new kind of bronzes casting including these elements. Make additions to the Cu-Al-Fe-Ni bronze of Si, Cr, Mo and/or W in the rise of these properties makes possible. The investigations of the surface distribution of the concentration of elements in the microstructure of the studied bronze on X-ray microanalyzer were conducted. It results from conducted investigations, that in the aluminium bronze BA1055 after makes additions Si, Cr, Mo and/or W the phases of the type κFe, κNi crystallize, probably as complex silicides. Elements such as: Fe and Si dissolve first of all in phases κ, in smaller stage in the matrix of the bronze; Mn, Ni and W they dissolve in matrix and phases κ. It dissolves Cr and Mo in the larger stage in phases κ than in the matrix. The sizes of the abrasive wear were compared in the state cast multicomponentnew casting Cu-Al-Fe-Ni bronzes with the additives Cr, Mo or W with the wear of the bronze CuAl10Fe5Ni5Si. The investigations of thewear were conducted on the standard device. It results from conducted investigations, that make additions to bronze BA1055 of the additives of Si, Cr, Mo, and/or W it influences the rise of the hardness (HB of the bronze in the cast state, in the result of the enlarged quantity separates of hard phases κ, and in the consequence the decrease of the abrasive wear. The addition of molybdenum made possible obtainment of the microhardness of the phase α and γ 2 on the comparable level. From the microstructure of the bronze CuAl10Fe5Ni5MoSi is characterizes the smallest abrasive wear among

  3. Metallurgical and Chemical Characterization of Bronze Remains Found at the Houhe Site in Shanxi Province, China

    Science.gov (United States)

    Mu, D.; Nan, P. H.; Wang, J. Y.; Song, G. D.; Luo, W. G.

    2015-07-01

    This study attempts to determine the metallurgical and chemical characteristics of Chinese bronze artifacts from the early Iron Age by taking the bronze artifacts from the Houhe site as an example. The bronze artifacts included vessels, buckles, mirrors, and bells. Elemental compositions of 10 Chinese bronze artifacts from the Houhe site were determined by an x-ray fluorescence system. Microstructures were observed by a polarizing microscope. Most of the artifacts were cast and lacked external evidence of secondary processing. The copper content of the vessels is higher than the other samples, and the copper content of buckles is the lowest. High tin content is a distinctive characteristic of the mirrors. Through comparisons, bells show a decline in the content of copper from the Western Zhou dynasty to the early Han dynasty, and the content of lead increased over time. Combined with historical studies, the findings show that there may have been industrial standards for bronze production during the Han dynasty.

  4. Determining Foundry Area of Bronze Vessel Using REE in Clay Mould Residues

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The composition of casting clay core might provide clue to the foundry area of the bronze vessels. REE analysis of the residual clay mould was conducted by inductively coupled plasma atomic emission spectrometer (ICP-AES). Results reveal that characteristic of REE of clay mould from different region is dissimilar. It is feasible to restrict the possible foundry area of the bronze vessels on the basis of analysis of REE of clay mould residues on the bronzes. Meanwhile, this paper attempts to determine the foundry area of the bronze vessels unearthed at Jiuliandun tombs of Chu State, dated back to Warring States Period, in Zaoyang City, Hubei Province, and at Zuozhong cemetery, Spring and Autumn Period, in Jingmen City, Hubei Province. REE of clay core provides information on the foundry area of bronze vessels.

  5. Preliminary result on the analysis of Late Bronze Age metals

    International Nuclear Information System (INIS)

    Complete text of publication follows. The main event of the complex cultural changes during the transition from Middle to Late Bronze Age was the appearance of Tumulus culture in the Danube-Tisza region. In this period people rose mounds (tumuli) above their graves made from stone and soil. According to our present knowledge we believe that the ethnically inhomogeneous Tumulus culture was made homogenous by commerce (especially bronze commerce). Depots were typical of the final period of Middle Bronze Age called Koszider-phase. During the tumulus period the practice of hiding depots came to its end, bronze objects were put into graves. Therefore, it would be important to analyze the relation between the Koszider and Tumulus metallurgy. The main question to be answered is the following: were the trade connections and exchange of goods discontinued during the time of cultural changes? Examination of archaeological finds is carried out usually by typological methods which provide information on the attire fashion and funeral rite of cultures. The inherent capability of analytical techniques makes it possible to draw conclusions on the provenance of metals, thus facilitating to establish the contemporary trade routes. The metal finds from the southern part of the Great Hungarian Plain has not been investigated yet, though it would be important from the point of view of Tumulus culture. The main question is whether there is any noticeable change between the metallurgical craftsmanship of the consecutive eras. Therefore, it is important to determine the composition of the used raw materials, their sources, as well as the applied manufacturing technologies. For the characterization of archaeological bronze finds both conventional X-ray fluorescence (XRF) method and micro proton induced X-ray fluorescence (micro-PIXE) techniques are applied. The first one serves for the determination of the bulk composition of samples while the second one for the characterization of

  6. Chisels in the italian Bronze Age: technological and typological aspects

    Directory of Open Access Journals (Sweden)

    Speciale, Claudia

    2010-12-01

    Full Text Available Bronze chisels are tools used “à percussion posée”; this means they need a minimum length and some functional parts (tang, body, blade; they could have a handle of perishable material and they were used with a hammer to work wood, bronze and other materials. Chisels can be classified following their functional parts; the first element is the shape (rod or socketed chisel; the second one is body section; the third one is tang section. Chronology and distribution of every type were identified to obtain a general view of this class of tools during the Italian Bronze Age.

    Los cinceles de bronce son herramientas que se utilizan en percusión apoyada (à percussion posée, por consiguiente, necesitan una longitud mínima y algunas partes funcionales (empuñadura, cuerpo, hoja; podrían tener un mango de material perecedero. Se utilizan con un martillo en el labrado de la madera, del bronce y de otros materiales. Los cinceles se pueden clasificar de acuerdo con los siguientes elementos funcionales: el primero es la forma (cincel de varilla o de cubo; el segundo es la sección del cuerpo; el tercero es la sección de la empuñadura. La cronología y la distribución de cada tipo se identificaron para obtener una visión general de esta clase de instrumentos durante la Edad del Bronce en Italia.

  7. Abertura floral de Dendranthema grandiflora Tzvelev. ´Bronze Repin´após rmazenamento a frio seguido de ?pulsing?

    OpenAIRE

    Bellé Rogério Antônio; Mainardi Jucelma de Cássia Câmara Tolotti; Mello Josué Benetti; Zachet Divar

    2004-01-01

    Visando estudar a abertura de inflorescências e a vida de vaso de crisântemo (Dendranthema grandiflora Tzvelev. ?Bronze Repin?) colhido precocemente, montou-se um experimento em delineamento inteiramente casualizado bifatorial 2 x 6 com cinco repetições, realizado no Departamento de Fitotecnia da Universidade Federal de Santa Maria. As hastes foram armazenadas a 2ºC ou 5ºC por sete dias, sendo em seguida tratadas com soluções de ?pulsing? por 24h e mantidas em vasos com água de torneira, reno...

  8. Novel polar dielectrics with the tetragonal tungsten bronze structure

    OpenAIRE

    Andrei ROTARU

    2013-01-01

    There is great interest in the development of new polar dielectric ceramics and multiferroic materials with new and improved properties. A family of tetragonal tungsten bronze (TTB) relaxors of composition Ba₆M³⁺Nb₉O₃₀ (M³⁺ = Ga³⁺, Sc³⁺ and In³⁺, and also their solid solutions) were studied in an attempt to understand their dielectric properties to enable design of novel polar TTB materials. A combination of electrical measurements (dielectric and impedance spectroscopy) and powder diffr...

  9. Analysis of selective laser cleaning of patina on bronze coins

    Science.gov (United States)

    Buccolieri, G.; Nassisi, V.; Torrisi, L.; Buccolieri, A.; Castellano, A.; Di Giulio, M.; Giuffreda, E.; Delle Side, D.; Velardi, L.

    2014-04-01

    The patina, is the result of a large number of chemical, electrochemical and physical processes which occur spontaneously during interaction of metal surfaces with the environment. In this work we want to analyze and remove the patina in artefacts, exposed to atmosphere for various decades. Here, experimental results about the laser cleaning of bronze coins by KrF (248 nm) and Nd:YAG (532 nm) lasers are reported. Both laser wavelengths were efficient to reduce the chlorine concentration on the surface of the coins more than 80 %, as demonstrated by Energy Dispersive X-Ray Fluorescence analyses.

  10. Analysis of selective laser cleaning of patina on bronze coins

    International Nuclear Information System (INIS)

    The patina, is the result of a large number of chemical, electrochemical and physical processes which occur spontaneously during interaction of metal surfaces with the environment. In this work we want to analyze and remove the patina in artefacts, exposed to atmosphere for various decades. Here, experimental results about the laser cleaning of bronze coins by KrF (248 nm) and Nd:YAG (532 nm) lasers are reported. Both laser wavelengths were efficient to reduce the chlorine concentration on the surface of the coins more than 80 %, as demonstrated by Energy Dispersive X-Ray Fluorescence analyses.

  11. Investigation of laser cleaning on bronze cultural relics

    Science.gov (United States)

    Ling, Xiulan; Wang, Gao; Zhang, Chen

    2016-05-01

    The effects of laser cleaning on the corrosion layers of bronze cultural relics were studied using a pulsed fiber laser. The laser cleaning threshold value of the corrosion layers was obtained. It was found that the corrosion layer was removed successfully by employing a laser fluence value of 0.32 J cm-2 and scanning for three times. To obtain experimental evidence, laser con-focal scanning microscopy, scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), laser induced breakdown spectroscopy (LIBS) and laser Raman spectroscopy were employed to investigate the cleaning efficiency of corrosion layers on specimens.

  12. Bronze analysis by k0-NAA and PIXE

    International Nuclear Information System (INIS)

    Five copper alloys were prepared with modern powder metallurgical processes in the frame of the European project 'Improvement of Means of Measurement on Archaeological Copper-Alloys for Characterisation and Conservation (IMMACO)' and certified for As, Pb, Sn and Zn mass fractions. Similar in their composition to archaeological bronze alloys, these Certified Reference Materials (CRMs) are to be used for calibration of XRF instruments for characterization of archaeological samples either in the laboratory or in the field. Successful contribution of non-destructive analytical methods (k0-NAA and PIXE) to the IMMACO project and to the certification of the five reference materials is presented. (author)

  13. Prevention of Dealloying in Manganese Aluminium Bronze Propeller: Part II

    Directory of Open Access Journals (Sweden)

    Napachat Tareelap

    2014-03-01

    Full Text Available Due to the failure of manganese aluminium bronze (MAB propeller caused by dealloying corrosion as described in Part I [1], this work aims to study the prevention of dealloying corrosion using aluminium and zinc sacrificial anodes. The results indicated that both of the sacrificial anodes could prevent the propeller from dealloying. Moreover, the dealloying in seawater was less than that found in brackish water. It was possible that hydroxide ions, from cathodic reaction, reacted with calcium in seawater to form calcium carbonate film protecting the propeller from corrosion.

  14. Maude como marco semántico ejecutable

    OpenAIRE

    Verdejo López, José Alberto

    2003-01-01

    La lógica de reescritura, propuesta por José Meseguer en 1990 como marco de unificación de modelos de computación concurrente, es una lógica para razonar sobre sistemas concurrentes con estado que evolucionan por medio de transiciones. Desde su definición, se ha propuesto a la lógica de reescritura como marco lógico y semántico en el cual poder expresar de forma natural otras muchas lógicas, lenguajes y modelos de computación. Además, la lógica de reescritura es ejecutable utilizando el lengu...

  15. La docencia en el marco de la responsabilidad social universitaria

    Directory of Open Access Journals (Sweden)

    Luis José Vera Guadrón

    2012-01-01

    Full Text Available El presente artículo tiene como objetivo analizar la docencia en el marco de la responsabilidad social universitaria del profesor en el Programa Educación de la Universidad Nacional Experimental Rafael María Baralt. El tipo de investigación fue descriptiva, con diseño no experimental, de campo y transeccional; los resultados indicaron que los profesores cumplen con la docencia en el marco de la responsabilidad social universitaria. Se concluye que existe conocimiento del contexto institucional para desarrollar la docencia pero desvinculada de la investigación y extensión; se recomienda planificar talleres de formación para evitar la docencia parcelada, sin pertinencia social y científica.

  16. Programa Regional de Indicadores de Desarrollo Infantil (PRIDI): Marco Conceptual

    OpenAIRE

    Patrice Engle; Santiago Cueto; María Estela Ortíz; Aimee Verdisco

    2011-01-01

    El presente documento entrega el marco conceptual y la fundamentación del Proyecto Regional de Indicadores de Desarrollo Infantil (PRIDI), una iniciativa del Banco Interamericano de Desarrollo (BID), cuyo objetivo es generar un programa regional de compilación y uso de datos e indicadores comparables de resultados sobre Desarrollo Infantil (DI). Inspirado por las experiencias del Banco en apoyar pruebas estandarizadas como son el LLECE y el SERCE, esperamos que el carácter regional de los res...

  17. Environmental roots of the late bronze age crisis.

    Science.gov (United States)

    Kaniewski, David; Van Campo, Elise; Guiot, Joël; Le Burel, Sabine; Otto, Thierry; Baeteman, Cecile

    2013-01-01

    The Late Bronze Age world of the Eastern Mediterranean, a rich linkage of Aegean, Egyptian, Syro-Palestinian, and Hittite civilizations, collapsed famously 3200 years ago and has remained one of the mysteries of the ancient world since the event's retrieval began in the late 19(th) century AD/CE. Iconic Egyptian bas-reliefs and graphic hieroglyphic and cuneiform texts portray the proximate cause of the collapse as the invasions of the "Peoples-of-the-Sea" at the Nile Delta, the Turkish coast, and down into the heartlands of Syria and Palestine where armies clashed, famine-ravaged cities abandoned, and countrysides depopulated. Here we report palaeoclimate data from Cyprus for the Late Bronze Age crisis, alongside a radiocarbon-based chronology integrating both archaeological and palaeoclimate proxies, which reveal the effects of abrupt climate change-driven famine and causal linkage with the Sea People invasions in Cyprus and Syria. The statistical analysis of proximate and ultimate features of the sequential collapse reveals the relationships of climate-driven famine, sea-borne-invasion, region-wide warfare, and politico-economic collapse, in whose wake new societies and new ideologies were created. PMID:23967146

  18. Environmental roots of the late bronze age crisis.

    Directory of Open Access Journals (Sweden)

    David Kaniewski

    Full Text Available The Late Bronze Age world of the Eastern Mediterranean, a rich linkage of Aegean, Egyptian, Syro-Palestinian, and Hittite civilizations, collapsed famously 3200 years ago and has remained one of the mysteries of the ancient world since the event's retrieval began in the late 19(th century AD/CE. Iconic Egyptian bas-reliefs and graphic hieroglyphic and cuneiform texts portray the proximate cause of the collapse as the invasions of the "Peoples-of-the-Sea" at the Nile Delta, the Turkish coast, and down into the heartlands of Syria and Palestine where armies clashed, famine-ravaged cities abandoned, and countrysides depopulated. Here we report palaeoclimate data from Cyprus for the Late Bronze Age crisis, alongside a radiocarbon-based chronology integrating both archaeological and palaeoclimate proxies, which reveal the effects of abrupt climate change-driven famine and causal linkage with the Sea People invasions in Cyprus and Syria. The statistical analysis of proximate and ultimate features of the sequential collapse reveals the relationships of climate-driven famine, sea-borne-invasion, region-wide warfare, and politico-economic collapse, in whose wake new societies and new ideologies were created.

  19. Corrosion characteristics of copper and leaded bronze in palm biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Haseeb, A.S.M.A.; Masjuki, H.H.; Ann, L.J.; Fazal, M.A. [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2010-03-15

    Biodiesel has become more attractive as alternative fuel for automobiles because of its environmental benefits and the fact that it is made from renewable sources. However, corrosion of metals in biodiesel is one of the concerns related to biodiesel compatibility issues. This study aims to characterize the corrosion behavior of commercial pure copper and leaded bronze commonly encountered in the automotive fuel system in diesel engine. Static immersion tests in B0, B50 and B100 fuels were carried out at room temperature for 2640 h. Similar immersion tests in B0, B100 and B100 (oxidized) fuels were also conducted at 60 C for 840 h. At the end of the test, corrosion behavior was investigated by weight loss measurements and changes in surface morphology. Fuels were analyzed by using TAN analyzer, FTIR, MOA (multi-element oil analyzer) to investigate acid concentration, oxidation level with water content and corrosive impurities respectively. Results showed that under the experimental conditions, pure copper was more susceptible to corrosion in biodiesel as compared to leaded bronze. (author)

  20. Investigation into anodic dissolution of sodium-tungsten bronzes in tungstate melt

    International Nuclear Information System (INIS)

    Anodic dissolution of monocrystals of sodium-tungsten bronzes and tungsten in tungstate melts with different content of tungsten trioxide (20, 40, 60 mol%) is studied. It is shown that the dissolution of sodium-tungsten bronze at small current densities on the both electrodes proceeds reversibly in terms of identical chemical behaviour of cathode and anode processes and small polarization. As the current density increases, the process becomes complicated by the fact that alongside with the dissolution of bronzes their solid-phase oxidation takes place

  1. Investigation into anodic dissolution of sodium-tungsten bronzes in tungstate melt

    Energy Technology Data Exchange (ETDEWEB)

    Aksent' ev, A.G.; Kaliev, K.A.; Baraboshkin, A.N. (AN SSSR, Sverdlovsk. Inst. Ehlektrokhimii)

    1982-05-01

    Anodic dissolution of monocrystals of sodium-tungsten bronzes and tungsten in tungstate melts with different content of tungsten trioxide (20, 40, 60 mol%) is studied. It is shown that the dissolution of sodium-tungsten bronze at small current densities on both electrodes proceeds reversibly in terms of identical chemical behaviour of cathode and anode processes and small polarization. As the current density increases, the process becomes complicated by the fact that alongside with the dissolution of bronzes their solid-phase oxidation takes place.

  2. Palaeoethnobotanical Data from the High Mountainous Early Bronze Age Settlement of Tsaghkasar-1 (Mt. Aragats, Armenia

    Directory of Open Access Journals (Sweden)

    Roman Hovsepyan

    2011-09-01

    Full Text Available Palaeoethnobotanical investigations suggest that at least part of the Early Bronze Age population of Tsaghkasar was settled and practiced agriculture in the high mountainous zone. People there appear to have cultivated hexa‐ and tetraploid wheats (probably bread wheat and emmer and barley (possibly hulled. Bronze Age agriculture in the Southern Caucasus differs from earlier and later period when cultivation of pulses, oil‐producing plants, and other plants was common. This emphasis on the cultivation and use of certain cereal grains at Early Bronze sites such as Tsaghkasar can tentatively be added to a constellation of practices associated with the Kura‐Araxes culture in the South Caucasus.

  3. MarcoPolo-R: Asteroid Sample Return Mission

    Science.gov (United States)

    Brucato, John Robert

    2012-07-01

    MarcoPolo-R is a sample return mission to a primitive Near-Earth Asteroid (NEA) selected for the assessment study in the framework of ESA Cosmic Vision 2015-25 program. MarcoPolo-R is an European-led mission with a proposed NASA contribution. MarcoPolo-R will rendezvous with a primitive carbon-rich NEA, scientifically characterize it at multiple scales, and return a unique sample to Earth unaltered by the atmospheric entry process or terrestrial weathering. The baseline target is a binary asteroid (175706) 1996 FG3, which offers a very efficient operational and technical mission profile. A binary target also provides enhanced science return. The choice of this target will allow new investigations to be performed more easily than at a single object, and also enables investigations of the fascinating geology and geophysics of asteroids that are impossible at a single object. Several launch windows have been identified in the time-span 2020-2024. The baseline mission scenario of MarcoPolo-R to 1996 FG3 foresees a single primary spacecraft, carrying the Earth re-entry capsule and sample acquisition and transfer system, launched by a Soyuz-Fregat rocket from Kourou. The scientific payload includes state-of-the-art instruments, e.g. a camera system for high resolution imaging from orbit and on the surface, spectrometers covering visible, near-infrared and mid-infrared wavelengths, a neutral-particle analyser, a radio science experiment and optional laser altimeter. If resources are available, an optional Lander will be added to perform in-situ characterization close to the sampling site, and internal structure investigations. MarcoPolo-R will allow us to study the most primitive materials available to investigate early solar system formation processes. The main goal of the MarcoPolo-R mission is to return unaltered NEA material for detailed analysis in ground-based laboratories. Only in the laboratory can instruments with the necessary precision and sensitivity be

  4. History of a Bronze Age tell and its environment

    Science.gov (United States)

    Kovács, Gabriella; Füleky, György; Vicze, Magdolna

    2016-04-01

    Százhalombatta-Földvár is the most excessively researched Bronze Age tell site in Hungary. Parallel to the investigation of the settlement structure and activity patterns the changes of the landscape and the effect of human alteration is also studied. Significant changes of the landscape can be detected from the Bronze Age until the recent natural and cultural heritage protection of the area. Archaeological, soil analytical and thin section soil micromorphological methods are used to reconstruct the past 4000 years of the tell and its immediate surroundings. Prior to the Bronze Age the area was covered by forest vegetation, so the initial settling could only be realised after deforestation (2000 BC). The result of the soil corings and the prepared soil thin sections are solid proves of this action. It also became evident that at some areas - so far it seems that at locales where house floors were laid for the very first time - even the topsoil was removed so intensively that only the B horizon of the relict forest soil can be found. This observation needs to be further tested outside the habitation area to define the horizontal extension of the forest clearance and the topsoil removal. The northern side of the settlement is bordered by a natural erosion gully. At 2000 BC it was just a natural depression, but by 1500 BC it was deepened to serve as a fortification ditch. Around 1200 BC the ditch started to be filled in and by 1000 BC it was refilled to such an extent that its surface was utilised again. At about 600 BC (Late Iron Age) a smaller inner rampart was erected on the southern side of the ditch for inner separation. Not much is known about the Roman period of this area (200 AD) but the remnants of a watchtower indicate their presence. During the 18th century AD the area was used for grape cultivation and later for hobby gardens up until the protection of the area in the late 20th century. Since then species of the original vegetation started to grow back

  5. Abertura floral de Dendranthema grandiflora Tzvelev. ´Bronze Repin´após rmazenamento a frio seguido de “pulsing” Floral opening of Dendranthema grandiflora Tzvelev. ´Bronze Repin´after cold storage followed by pulsing

    OpenAIRE

    Rogério Antônio Bellé; Jucelma de Cássia Câmara Tolotti Mainardi; Josué Benetti Mello; Divar Zachet

    2004-01-01

    Visando estudar a abertura de inflorescências e a vida de vaso de crisântemo (Dendranthema grandiflora Tzvelev. ‘Bronze Repin’) colhido precocemente, montou-se um experimento em delineamento inteiramente casualizado bifatorial 2 x 6 com cinco repetições, realizado no Departamento de Fitotecnia da Universidade Federal de Santa Maria. As hastes foram armazenadas a 2ºC ou 5ºC por sete dias, sendo em seguida tratadas com soluções de “pulsing” por 24h e mantidas em vasos com água de torneira, reno...

  6. Effect of lattice instability on superconductivity in sodium tungsten bronze

    International Nuclear Information System (INIS)

    The effect of lattice instability on the electronic properties of the tungsten bronzes, M/subx/WO3(0 3, the effect on the superconducting transition temperature of a phonon which is assumed to soften as a function of x is explicitly calculated. Tunneling between the local free-energy minima is assisted by this soft phonon. Good agreement is obtained with recent experimental observations of a dramatic increase in T/subc/ as x decreases and approaches the critical value for transition between the superconducting and semiconducting tetragonal phases. Noteworthy features of this work are that the structural transformation does not correspond to a simple condensation of the soft phonon, and also that the phonon softening and configurational tunneling are considered simultaneously

  7. LAMQS analysis applied to ancient Egyptian bronze coins

    Science.gov (United States)

    Torrisi, L.; Caridi, F.; Giuffrida, L.; Torrisi, A.; Mondio, G.; Serafino, T.; Caltabiano, M.; Castrizio, E. D.; Paniz, E.; Salici, A.

    2010-05-01

    Some Egyptian bronze coins, dated VI-VII sec A.D. are analyzed through different physical techniques in order to compare their composition and morphology and to identify their origin and the type of manufacture. The investigations have been performed by using micro-invasive analysis, such as Laser Ablation and Mass Quadrupole Spectrometry (LAMQS), X-ray Fluorescence (XRF), Laser Induced Breakdown Spectroscopy (LIBS), Electronic (SEM) and Optical Microscopy, Surface Profile Analysis (SPA) and density measurements. Results indicate that the coins have a similar bulk composition but significant differences have been evidenced due to different constituents of the patina, bulk alloy composition, isotopic ratios, density and surface morphology. The results are in agreement with the archaeological expectations, indicating that the coins have been produced in two different Egypt sites: Alexandria and Antinoupolis. A group of fake coins produced in Alexandria in the same historical period is also identified.

  8. Cavitation erosion behavior of nickel-aluminum bronze weldment

    Institute of Scientific and Technical Information of China (English)

    李小亚; 闫永贵; 许振明; 李建国

    2003-01-01

    Cavitation erosion behavior of nickel-aluminum bronze(NAB)weldment in 3.5% NaCl aqueous solution was studied by magnetostrictive vibratory device for cavitation erosion.The results show that cavitation erosion resistance of the weld zone(WZ)of the weldment is superior to that of the base metal.SEM observation of eroded specimens reveals that the phases undergoing selective attack by the stress of cavitation erosion at the early stage of cavitation erosion are:martensite in the WZ,α phase in the heat-affected zone(HAZ)and eutectoidal phase in the base metal; the microcracks causing cavitation damage initiate at the phase boundaries.

  9. Analysis of an ancient bronze statue by external beam pixe

    International Nuclear Information System (INIS)

    A quantitative analysis of an ancient Buddha statue was performed by external beam Proton Induced X-ray Emission for the purpose of identifying its originality. It is shown how the PIXE method can be applied for archeological study. The elemental composition of the statue is compared with that of several samples with definite ages. The experiment was performed by extracting 2.4 MeV proton beam through a 2 mm diameter collimator and 7.6 μm kapton foil to the He atmosphere. X-rays were measured by a Si(Li) detector. The analysed elements were Fe, Cu, Ag, Au and Hg for gold coating and Fe, Ni, Cu, Zn, As, Ag, Sn, Au, Pb and Bi for bronze body. (author) 11 refs.; 4 figs.; 2 tabs

  10. LAMQS analysis applied to ancient Egyptian bronze coins

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, L., E-mail: lorenzo.torrisi@unime.i [Dipartimento di Fisica dell' Universita di Messina, Salita Sperone, 31, 98166 Messina (Italy); Caridi, F.; Giuffrida, L.; Torrisi, A. [Dipartimento di Fisica dell' Universita di Messina, Salita Sperone, 31, 98166 Messina (Italy); Mondio, G.; Serafino, T. [Dipartimento di Fisica della Materia ed Ingegneria Elettronica dell' Universita di Messina, Salita Sperone, 31, 98166 Messina (Italy); Caltabiano, M.; Castrizio, E.D. [Dipartimento di Lettere e Filosofia dell' Universita di Messina, Polo Universitario dell' Annunziata, 98168 Messina (Italy); Paniz, E.; Salici, A. [Carabinieri, Reparto Investigazioni Scientifiche, S.S. 114, Km. 6, 400 Tremestieri, Messina (Italy)

    2010-05-15

    Some Egyptian bronze coins, dated VI-VII sec A.D. are analyzed through different physical techniques in order to compare their composition and morphology and to identify their origin and the type of manufacture. The investigations have been performed by using micro-invasive analysis, such as Laser Ablation and Mass Quadrupole Spectrometry (LAMQS), X-ray Fluorescence (XRF), Laser Induced Breakdown Spectroscopy (LIBS), Electronic (SEM) and Optical Microscopy, Surface Profile Analysis (SPA) and density measurements. Results indicate that the coins have a similar bulk composition but significant differences have been evidenced due to different constituents of the patina, bulk alloy composition, isotopic ratios, density and surface morphology. The results are in agreement with the archaeological expectations, indicating that the coins have been produced in two different Egypt sites: Alexandria and Antinoupolis. A group of fake coins produced in Alexandria in the same historical period is also identified.

  11. LAMQS analysis applied to ancient Egyptian bronze coins

    International Nuclear Information System (INIS)

    Some Egyptian bronze coins, dated VI-VII sec A.D. are analyzed through different physical techniques in order to compare their composition and morphology and to identify their origin and the type of manufacture. The investigations have been performed by using micro-invasive analysis, such as Laser Ablation and Mass Quadrupole Spectrometry (LAMQS), X-ray Fluorescence (XRF), Laser Induced Breakdown Spectroscopy (LIBS), Electronic (SEM) and Optical Microscopy, Surface Profile Analysis (SPA) and density measurements. Results indicate that the coins have a similar bulk composition but significant differences have been evidenced due to different constituents of the patina, bulk alloy composition, isotopic ratios, density and surface morphology. The results are in agreement with the archaeological expectations, indicating that the coins have been produced in two different Egypt sites: Alexandria and Antinoupolis. A group of fake coins produced in Alexandria in the same historical period is also identified.

  12. Spectrophotometric determination of beryllium in bronzes with chrome azurol S

    International Nuclear Information System (INIS)

    Some remarks on the spectrophotometric determination of beryllium in bronzes using Chrome Azurol S (CAS) are given. The determination was performed at pH=6.5 and 10.0 using hexamethylene-tetramine and ammoniacal buffers, respectively. It was demonstrated that the determination of Be with CAS at pH=10.0 is slightly less sensitive, but it has two advantages which are important in obtaining reliable results. First, is the shorter time to reach the equilibrium between Be and CAS, and second, is lower pH sensitivity so that a better precision of the results at pH=10.0 overcompensate the slightly lower sensitivity at this pH in comparison with that at pH=6.5. (Author)

  13. Microcrystalline sodium tungsten bronze nanowire bundles as efficient visible light-responsive photocatalysts.

    Science.gov (United States)

    Wang, Lei; Zhan, Jinhua; Fan, Weiliu; Cui, Guanwei; Sun, Honggang; Zhuo, Linhai; Zhao, Xian; Tang, Bo

    2010-12-14

    Microcrystalline sodium tungsten bronze nanowire bundles were obtained via a facile hydrothermal synthesis, and were applied in water purification as visible-light-driven photocatalysts for the first time. PMID:20953497

  14. The Bronze "Ding of Flourishing Olympic "for the Main Stadium of the 2008 Olympic Games

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The bronze "Ding of Flourishing Olympic" for the main stadium of the 2008Olympic Games has been completed by Yuda Group Company. The "Ding of Flourishing Olympic" was designed by Lanzhou Ludu Chunqiu Cultural Disseminating Co. Ltd.

  15. Synchrotron X-ray diffraction and imaging of ancient Chinese bronzes

    International Nuclear Information System (INIS)

    High-energy synchrotron X-ray diffraction and imaging experiments were performed at the Advanced Photon Source on two ancient Chinese bronzes from the Art Institute of Chicago with the goal to nondestructively study their microstructure. The first object, a bronze fragment from an early Western Zhou dynasty vessel (Hu, 11th/10th century B.C.), was investigated with spatially-resolved diffraction to reveal the depth and composition of the surface corrosion layer as well as the composition and grain size of the underlying bronze core. The second object, a bronze dagger-axe (Ge, 3rd/2nd century B.C.) with a silver-inlaid sheath, was studied under both diffraction and imaging conditions. It was found to have been cast as a single object, answering longstanding scholars' questions on whether the ceremonial object concealed an interior blade. (orig.)

  16. University receives 2009 Governor's Environmental Excellence Bronze Medal for Campus Tree Tour 2008 Event

    OpenAIRE

    West, Hilary

    2009-01-01

    Virginia Tech received the 2009 Governor's Environmental Excellence Bronze Medal in the Environmental Project (Government) category for hosting the Campus Tree Tour 2008 tree planting event in Blacksburg on Oct. 21, 2008.

  17. Influence Cr on Crystallization and the Phase Transformations of the Bronze BA1044

    Directory of Open Access Journals (Sweden)

    B. P. Pisarek

    2007-07-01

    Full Text Available The investigations were introduced in the paper, method of thermal and derivative analysis (TDA, the process of crystallization and phase transformation in the solid state of the aluminium bronze CuA110Fe4Ni4 (BA1044 and with the addition 0.3% Cr. Two intermetallic phase were identified in the microstructure of the bronze BA1044: κFel - rich in Fe and Cu and κFe2 - rich in Fe, and in the microstructure of the bronze BA1044+0.3 % Cr only one phase κFel - rich in Fe, Cu and Cr. The presence of chrome in the bronze BA1044 reduce size the primary crystals of the phase β, reduces the dynamics of the processes of thermal phase transformation in the solid state and lengthens the time their of duration.

  18. The multidimensional evaluation and treatment of anxiety in children and adolescents: rationale, design, methods and preliminary findings Avaliação multidimensional e tratamento da ansiedade em crianças e adolescentes: marco teórico, desenho, métodos e resultados preliminares

    Directory of Open Access Journals (Sweden)

    Giovanni Abrahão Salum

    2011-06-01

    Full Text Available OBJECTIVE: This study aims to describe the design, methods and sample characteristics of the Multidimensional Evaluation and Treatment of Anxiety in Children and Adolescents - the PROTAIA Project. METHOD: Students between 10 and 17 years old from all six schools belonging to the catchment area of the Primary Care Unit of Hospital de Clínicas de Porto Alegre were included in the project. It comprises five phases: (1 a community screening phase; (2 a psychiatric diagnostic phase; (3 a multidimensional assessment phase evaluating environmental, neuropsychological, nutritional, and biological factors; (4 a treatment phase, and (5 a translational phase. RESULTS: A total of 2,457 subjects from the community were screened for anxiety disorders. From those who attended the diagnostic interview, we identified 138 individuals with at least one anxiety disorder (apart from specific phobia and 102 individuals without any anxiety disorder. Among the anxiety cases, generalized anxiety disorder (n = 95; 68.8%, social anxiety disorder (n = 57; 41.3% and separation anxiety disorder (n = 49; 35.5% were the most frequent disorders. CONCLUSION: The PROTAIA Project is a promising research project that can contribute to the knowledge of the relationship between anxiety disorders and anxiety-related phenotypes with several genetic and environmental risk factors.OBJETIVO: o objetivo deste estudo é descrever o desenho, os métodos e as características amostrais da Avaliação Multidimensional e Tratamento da Ansiedade em Crianças e Adolescentes - Projeto PROTAIA. MÉTODO: Escolares entre 10 e 17 anos de todas as escolas pertencentes à área de abrangência da unidade de atenção primária do Hospital de Clínicas de Porto Alegre foram incluídos no projeto. O projeto compreende cinco fases: 1 triagem comunitária; 2 diagnóstico psiquiátrico; 3 avaliação multidimensional, incluindo fatores ambientais, neuropsicológicos, nutricionais e marcadores biológicos; 4

  19. Ley marco de aseguramiento universal en salud, bajo la lupa

    Directory of Open Access Journals (Sweden)

    Leoncio Díaz

    2009-04-01

    Full Text Available La Ley Marco de Aseguramiento Universal en Salud, concebida en el marco del modelo neoliberal conservador, excluyente y polarizante, fue aprobada en circunstancias en la que persisten grandes contrastes entre sistemas de salud. Por un lado, los países que mantienen subsistemas inconexos y privatizados y, por otro, los que unificados y bajo la responsabilidad del Estado, garantizan a todos el acceso integral, gratuito y de calidad a los servicios de salud. En América y el Caribe, existen países cuyos pobladores carecen de derechos y posibilidades, evidenciando las profundas inequidades que mantienen en exclusión a la mayoría pobre y de extrema pobreza, entre ellos, el Perú muestra indicadores de salud que aún se mantienen en cifras alarmantes y por debajo de los que presentan otras realidades en el mundo. En las últimas tres décadas hubo ensayos frustros de reformas, como la integración funcional del Ministerio de Salud con el Instituto Peruano de Seguridad Social, o el Sistema Nacional Coordinado y Descentralizado en Salud. Actualmente se formula la Ley Marco de Aseguramiento Universal, que mantiene los actuales subsistemas sin variación alguna y con sus propias autonomías, ensayando pilotos, estableciendo planes parciales, implementándola de manera progresiva, priorizando la privatización y debilitando la función rectora del Ministerio de Salud, al crear una superintendencia omnipotente, lo cual continuará permitiendo la exclusión social de más de 9 millones de peruanos. Existe, por tanto, la necesidad de plantear la unificación de los subsistemas, para construir un Sistema Único de Salud, capaz de otorgar salud plena, integral, de calidad y sin costo alguno al 100% de ciudadanos.

  20. Análisis del futuro marco de referencia internacional

    Science.gov (United States)

    Cionco, G. R.; Arias, E. F.

    La técnica de interferometría de muy larga línea de base (VLBI) se aplica hoy a la astrometría para el cálculo de posiciones precisas de radiofuentes extragalácticas. Por tratarse de objetos lejanos, sus movimientos propios aparentes pueden considerarse nulos; esta propiedad hace que los catálogos de radiofuentes extragalácticas VLBI constituyan la mejor materialización de un sistema de referencia celeste inercial definido cinemáticamente. La Unión Astronómica Internacional (IAU) recomendó la adopción de un nuevo sistema de referencia celeste internacional materializado por las coordenadas ecuatoriales de objetos extragalácticos observados con le técnica VLBI. Para superar la precisión astrométrica actual es necesaria una mejora en la modelización de aquellos fenómenos que pueden introducir desviaciones sistemáticas en el marco de referencia celeste. El objetivo de este trabajo es poner de manifiesto las sistematicidades presentes en los distintos marcos de referencia elaborados con el próposito de materializar el nuevo sistema de referencia celeste de la IAU. Para la comparación de los distintos marcos de referencia se propone un modelo de tres rotaciones diferenciales más un término lineal que procura absorber los efectos sistemáticos presentes en las coordenadas. Se analiza igualmente la estabilidad de la solución cuando se utilizan distintos conjuntos de objetos de definición.

  1. The crystallisation of the aluminium bronze with additions of Si, Cr, Mo and/or W

    Directory of Open Access Journals (Sweden)

    B.P. Pisarek

    2007-08-01

    Full Text Available Purpose: The aim of this paper is description of the process of the crystallization of new aluminium bronzes with the complex silicides of the iron.Design/methodology/approach: Additions Cr, W, Mo and Si were introduced to create in the microstructure of the aluminium bronze of the complex silicides of the iron about high mechanical and physical proprieties to the bronze BA1044. The process of formation the microstructure of the bronze with use of the method of the thermal and derivative analysis (TDA was analysed. The examinations under the microscope and X-ray microanalysis of the surface distribution of elements were conducted.Findings: From carried research results, that in the aluminium bronze BA1044 after addition Si, Cr, Mo and/or W the phase κFe, κNi crystallize as the complex silicides of the iron. Elements such as: Fe and Si dissolve first of all in silicides in the smaller stage in the matrix of the bronze, Mn and Ni they dissolve in matrix and silicides, Cr dissolves in the larger stage in silicides than in the matrix, W and Mo dissolve in silicides however they crystallize as nanocrystals in the metal matrix and create with her composite.Research limitations/implications: Results of investigations of aluminium bronze BA1044 and alloys after adding to him about 1% Si were introduced in the article and suitably: 1.22 % Cr; 0.82 % Mo; 0.020 % W; 0.60 % Cr, 0.17 % Mo and 0.017 % W.Originality/value: The original results of the investigations of the crystallization of the new bronzes (innovative materials and casting technologies for which the process of arising microstructure the method TDA was not analysed so far were introduced in the article. The article possesses cognitive values not only essential for researcher but and practician-melters.

  2. Marco de trabajo para gestionar las competencias laborales

    OpenAIRE

    Franklin Sandoval; Doris Pernalete

    2014-01-01

    En este artículo se presenta un marco de trabajo innovador diseñado y desarrollado para posibilitar la realización de estudios inherentes con la gestión por competencia en los entornos laborales de la Administración Pública Venezolana (APV). Se analizaron los principales aspectos involucrados con la Gestión del Talento Humano (GTH), que se basan en la competencia laboral, las cuales mediante su desarrollo efectivo se constituyen en fuente principal para impulsar el logro de los objetivos empr...

  3. Instituciones y desarrollo económico. Un marco conceptual

    OpenAIRE

    Pablo Bandeira

    2009-01-01

    En los últimos años ha habido una explosión de trabajos econométricos que intentan identificar los factores que determinan el desarrollo económico. No obstante, la falta de una teoría que integre los aspectos económicos, políticos y culturales hace muy confusa la interpretación de los resultados. Este artículo propone un marco conceptual que ayude a entender los resultados econométricos de la literatura en ciencias sociales, extraer algunas conclusiones sobre las instituciones políticas y eco...

  4. Investigating Early/Middle Bronze Age copper and bronze axes by micro X-ray fluorescence spectrometry and neutron imaging techniques

    Science.gov (United States)

    Figueiredo, Elin; Pereira, Marco A. Stanojev; Lopes, Filipa; Marques, José G.; Santos, Joana P.; Araújo, M. Fátima; Silva, Rui J. C.; Senna-Martinez, João C.

    2016-08-01

    Micro X-ray fluorescence (micro-XRF) analysis and neutron imaging techniques, namely 2D radiography and 3D tomography, have been applied for the study of four metal axes from the Early/Middle Bronze Age in Western Iberia, a period characterized by a metallurgical change in the use of copper to bronze. Micro-XRF analysis has shown that one of the axes was produced in copper with some arsenic while the other three were produced in a copper-tin alloy (bronze) with variable tin contents and some arsenic and lead. Neutron radiography and tomography were applied to study internal heterogeneities of the axes in a non-invasive way since the specificities of neutron interaction with matter allow a suitable penetration of these relatively thick copper-based objects when compared to the use of a conventional X-ray radiography. Neutron imaging allowed the visualization of internal fissures and pores and the evaluation of their distribution, size and shape. Relevant information for the reconstruction of ancient manufacturing techniques was gathered, revealing that one ax was produced with the mold in an angle of ≈ 25°, probably to facilitate gas escape during metal pouring. Also, information regarding physical weaknesses of the axes was collected, providing relevant data for their conservation. The combination of these non-destructive techniques allowed the evaluation of the metal composition and the internal structure of the axes. Micro-XRF allowed the distinction among copper and bronze axes, and provided data about the composition of early bronzes for which data is scarce. The neutron imaging study allowed for the first time the visualization of internal heterogeneities in early bronze axes, namely pores and large voids, providing relevant information for the reconstruction of ancient manufacturing techniques and raising pertinent information regarding physical weaknesses of these types of objects.

  5. Characterisation of Late Bronze Age large size shield nails by EDXRF, micro-EDXRF and X-ray digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, E., E-mail: elin@itn.pt [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal); Departamento de Conservacao e Restauro, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal); Araujo, M.F. [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Silva, R.J.C. [CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal); Senna-Martinez, J.C. [Centro de Arqueologia (Uniarq), Faculdade de Letras, Universidade de Lisboa, 1600-214 Lisboa (Portugal); Ines Vaz, J.L. [Departamento de Letras, Universidade Catolica, Estrada da Circunvalacao, 3504-505 Viseu (Portugal)

    2011-09-15

    In the present study six exceptional large size metallic nails, a dagger and a sickle from the Late Bronze Age archaeological site of Figueiredo das Donas (Central Portugal) have been analysed by EDXRF, micro-EDXRF and X-ray digital radiography for the study of material composition and technology of fabrication. The combination of these analytical and examination techniques showed that all artefacts are made of bronze with As, Sb and Pb impurities, and that the nails were most likely manufactured using the casting-on technique. These results reinforce the use of binary bronze by Late Bronze Age in the region, and the incorporation of new fabrication technologies that resulted from ancient spheres of interaction. - Highlights: > EDXRF, micro-EDXRF and X-ray digital radiography in cultural heritage studies. > Archaeometallurgical study of a Late Bronze Age artefact collection from Portugal. > Practise of a specific and traditional bronze metallurgy. > Appearance of technological innovations as the casting-on technique.

  6. Comparative solar EUV flux for the San Marco ASSI

    Science.gov (United States)

    Tobiska, W. K.; Chakrabarti, S.; Schmidtke, G.; Doll, H.

    1993-01-01

    The Airglow and Solar Spectrometer Instrument (ASSI) on the San Marco D/L satellite has measured solar extreme ultraviolet irradiances. The data are currently being released for analysis. As a preliminary step in evaluating this important dataset, modeled solar irradiances from 4 to 105 nm are presented for comparison to the San Marco data. The comparable flux for March-December 1988 is obtained from a revised and extended empirical solar EUV model derived from OSO 1, OSO 3, OSO 4, OSO 6, AEROS A, and AE-E satellite and six rocket flight datasets. Solar rotational features are prominent on several occasions in the model time series. A useful example is the modeled integrated flux between 30-31 nm which includes the Si XI (30.3-nm) and He II (30.4-nm) irradiance. The modeled flux in this 1-nm range shows both an absolute 22 percent increase from beginning to end of mission and a solar rotational variability with a typical peak-to-valley ratio of 14 percent.

  7. Marco de trabajo para gestionar las competencias laborales

    Directory of Open Access Journals (Sweden)

    Franklin Sandoval

    2014-12-01

    Full Text Available En este artículo se presenta un marco de trabajo innovador diseñado y desarrollado para posibilitar la realización de estudios inherentes con la gestión por competencia en los entornos laborales de la Administración Pública Venezolana (APV. Se analizaron los principales aspectos involucrados con la Gestión del Talento Humano (GTH, que se basan en la competencia laboral, las cuales mediante su desarrollo efectivo se constituyen en fuente principal para impulsar el logro de los objetivos empresariales orientados en responder las necesidades del entorno laboral y las exigencias del mercado. El desarrollo, se fundamento en el dominio del conocimiento de las competencias laborales y perfiles de cargos que estructura el proceso de gestión sobre tres actividades: 1 identificación, 2 desarrollo y 3 evaluación. El método utilizado, fue proyectivo y permitió obtener un marco de trabajo en el que se describe una metodología, la cual establece formalmente las reglas, estándares, así como secuencias de pasos para la caracterización de la competencia laboral y, sobre todo, la gestión que promueve las tareas y roles para la toma de decisiones.

  8. A História da enfermagem em Pernambuco: um olhar da ABEn (1968-1972

    Directory of Open Access Journals (Sweden)

    Fatima Maria da Silva Abrão

    2001-06-01

    Full Text Available Este artigo é uma tentativa de contribuir com a história da enfermagem ao levantar questões relevantes, marcos e influências que através da Associação Brasileira de Enfermagem foram vislumbrados na época. Através de depoimento oral e análise de documentos pudemos destacar ampla atuação da associação relacionadas à questões trabalhistas, normatização do exercício profissional, formação profissional, atividades sócio-culturais e educativas da enfermagem em Pernambuco.

  9. Marco Polo’s 'Devisement dou monde' and Franco-Italian tradition

    Directory of Open Access Journals (Sweden)

    Alvise Andreose

    2015-02-01

    Full Text Available The manuscript BNF fr. 1116 (F is the best surviving witness of the Devisement dou monde both for the quality of its reading and because it offers the closest version to the original form of the text. The book was written by Marco Polo, who had travelled for 24 years in Asia in the last quarter of the thirteenth century, and Rustichello da Pisa, an Arthurian romance writer, while both were prisoners in Genoa in 1298. The language in which the work was first written – an Old French heavily sprinkled with morphological as well as lexical Italianisms – is considered as a representative example of «Franco-Italian». The great heterogeneity of the texts usually included within this category, however, might provide an incorrect impression as regards both the original linguistic form of the Devisement and the audience to whom it was originally addressed. The language of the MS BNF fr. 1116 does not display strong similarities to the hybrid language used in Northern Italy for chivalric literature, which is traditionally called «Franco-Italian» or «Franco-Venetan». Some linguistic correspondences enable us to connect the MS BNF fr. 1116 with the group of Old French manuscripts copied by Pisan scribes while incarcerated in Genoa prison, following the battle of Meloria (1284. The fragment of the Devisement recently discovered by C. Concina appears to be very similar to F. Both graphic and phonetic evidences suggest that this witness, too, has to be localised to Tuscany.

  10. Modele a anticipations rationnelles de la conjoncture simulee : MARCOS.

    OpenAIRE

    Jacquinot, P.; Mihoubi, F.

    2000-01-01

    MARCOS est un modèle étalonné de l'économie française en présence d'anticipations rationnelles. Son principal objectif est la réalisation d'exercices de simulation sur un horizon de moyen long terme. Il a été construit en adoptant l'hypothèse d'un petit pays où les marchés des biens et du travail sont dans un contexte de concurrence monopolistique, les salaires sont négociés suivant un modèle de droit à gérer l'emploi et la consommation des ménages non contraints par les liquidités résulte d'...

  11. Marcos interpretativos, identidad e imaginario en el mexica movement

    Directory of Open Access Journals (Sweden)

    Aquiles Chihu Amparán

    2007-01-01

    Full Text Available El objetivo de este artículo es analizar el mexica movement, a través de su discurso e imaginario, representados en un conjunto de utopías, símbolos, mitos y creencias, que revitalizan la cultura y el pasado mesoamericano. Se aplica la metodología del análisis de los marcos (frame analysis, con sus cinco partes: el protagonista, el problema, el antagonista, las metas y la audiencia. En el estudio de los movimientos sociales ha prevalecido el análisis de los aspectos políticos y estructurales, aquí a dichos movimientos se les observa en función de sus capacidades como productores de significados, que contribuyen a conformar su identidad colectiva.

  12. Monitoring and assessment of regional air quality in China using space observations (Marco Polo)

    NARCIS (Netherlands)

    Ronald, A. van der; Timmermans, R.; Bai, J.; Zhang, Q.; Wal, L. van der

    2013-01-01

    In this paper we will present the FP7-project 'MarcoPolo'. The main objective of MarcoPolo is to improve air quality monitoring, modelling and forecasting over China using satellite data. During the project a new emission inventory will be constructed by combining Chinese and European expertise. It

  13. Exploring the bronzing effect at the surface of ink layers

    Science.gov (United States)

    Hébert, Mathieu; Mallet, Maxime; Deboos, Alexis; Chavel, Pierre; Kuang, Deng-Feng; Hugonin, Jean-Paul; Besbes, Mondher; Cazier, Anthony

    2015-03-01

    We investigate the optical phenomenon responsible for the colored shine that sometimes appears at the surface of ink layers in the specular direction, often called bronzing or gloss differential. It seems to come from the wavelength-dependent refractive index of the ink, which induces a wavelength-dependent reflectance of the ink-air interface. Our experiments on cyan and magenta inkjet inks confirm this theory. Complex refractive indices can be obtained from measurements of the spectral reflectance and transmittance of a transparency film coated with the ink. We propose a correction of the classical Clapper-Yule model in order to include the colored gloss in the prediction of the spectral reflectance of an inked paper. We also explored effects of scattering by the micrometric or nanometric roughness of the ink surface. The micrometric roughness, easy to model with a geometrical optics model, can predict the spreading of the colored gloss over a large cone. Electromagnetic models accounting for the effect of the nanometric roughness of the surface also predict the attenuation of short wavelengths observed under collimated illumination.

  14. Understanding metal–insulator transition in sodium tungsten bronze

    Indian Academy of Sciences (India)

    Sanhita Paul; Satyabrata Raj

    2015-06-01

    We have carried out angle-resolved photoemission spectroscopy (ARPES) and spectromicroscopy studies to understand the metal–insulator transition (MIT) observed in sodium tungsten bronzes, NaWO3. The experimentally determined band structure is compared with the theoretical calculation based on full-potential linear augmented plane-wave method. It has been found that there is a good gross agreement between experiment and theory. ARPES spectra on the insulating sample show that the states near F are localized due to the random distribution of Na in WO3 lattice which causes strong disorder in the system. Our spectromicroscopy measurements on both insulating and metallic samples do not approve percolation model to explain MIT in NaWO3. Photoemission spectroscopy on metallic samples does not show any Na-induced impurity band (level), which was one of the models to explain MIT. Electron-like Fermi surface(s) has been found from our experiment for metallic samples at the (X) point which shows good agreement with band calculation.

  15. Flux pinning in bronze-processed Nb3Sn wires

    International Nuclear Information System (INIS)

    The scaling law derived by Kramer for magnetic flux pinning in high magnetic fields was examined for its applicability to the magnetic field dependence of critical-current densities in the bronze processed monofilamentary Nb3Sn wires. From this it was concluded that: (1) its prediction for the form of the dependence of critical current on magnetic field and grain size [/J vector /sub c/ x H vector/ approx. h/sup 1/2/(1-h)2(1-a0√rho)-2] was found to be very good in most cases including wires with very small Nb3Sn grains (approx. 400 A). It was found very useful in comparison of J/sub c/ for different wires and in extrapolating to obtain H/sub c2/ for these wires. (2) However, it could not account consistently for the anisotropy in critical current of a tape which was measured with H applied perpendicular and parallel to the tape face. (3) The values of kappa1 which were determined with the scaling law were too small by a factor of 2 to 3, and the trend in the variation with heat-treating time was opposite to that which is reasonably to be expected. That the behavior of kappa1 is thus seriously in contradiction with the expected behavior for Nb3Sn suggests basic faults in the derivation of the scaling equation for critical currents at high magnetic fields

  16. Políticas urbanas no Brasil: marcos legais, sujeitos e instituições

    Directory of Open Access Journals (Sweden)

    Celene Tonella

    2013-04-01

    Full Text Available A questão urbana no Brasil - traduzida como o direito à cidade e à moradia digna - nas três últimas décadas passou por intensas transformações tanto em seus marcos regulatórios quanto na forma de envolvimento das diferentes instituições e sujeitos localizados na sociedade e no aparato estatal. Desde os debates que antecederam a Assembleia Nacional Constituinte na década de 1980, a mobilização tem sido intensa e marcada por tensões entre os diversos atores. Busca-se demonstrar as incorporações de diferentes sujeitos por meio de processos democráticos participativos, como conselhos e conferências, os resultados obtidos por meio da consolidação de legislação específica e os limites atuais da Política Urbana.The urban question in Brazil - translated as the right to the city and to dignity housing - in the three last decades has passed by intense transformations in its regulatory landmarks and in its forms of involvement of different institutions and citizens located in the society and in state apparatus. Since the debates that had preceded the National Constituent Assembly, in the decade of 1980, the mobilization has been intense and marked by tensions between diverse actors. We aim to demonstrate the incorporations of different citizens by democratic participatory processes, such as councils and conferences, the achievements of the consolidation of specific legislation and current limits of the Urban Policy.

  17. Dating simple flakes: Early Bronze Age flake production technology on the Middle Euphrates Steppe, Syria

    Directory of Open Access Journals (Sweden)

    Yoshihiro Nishiaki

    2014-03-01

    Full Text Available Aceramic flint scatters, comprising very crude cores or flakes and no formalised tools, are frequently found on the Middle Euphrates steppe of northern Syria. Previous studies suggest that many of them are residues of short-term activities by the nomads or shepherds of the Early Bronze Age. In order to verify this interpretation, a more precise chronological framework needs to be established for the Early Bronze Age lithic industry. This paper analyses stratified flake assemblages of the Early Bronze Age at Tell Ghanem al-Ali, a securely radiocarbon-dated settlement on the Middle Euphrates, and examines which occupation level yields assemblages most similar to those of the steppe. Results demonstrate that the lithic industry of this period underwent significant diachronic changes in terms of core reduction technology. Based on the chronological framework developed at Tell Ghanem al-Ali, the steppe assemblages in question can be assigned to different phases of the Early Bronze Age. This finding will help identify processes at the beginning of the extensive exploitation of the steppe, which is regarded as one of the most important socioeconomic changes that occurred among Early Bronze Age communities of the Middle Euphrates.

  18. Corrosion of Bronzes by Extended Wetting with Single versus Mixed Acidic Pollutants

    Directory of Open Access Journals (Sweden)

    Liliana Gianni

    2014-04-01

    Full Text Available The corrosion of bronzes was examined in the context of single-acid versus mixed-acid (as in urban acid rain solutions. Two bi-component bronzes (copper with either 3% Sn or 7% Sn that closely represent those of historic artifacts were immersed for five weeks in conditions designed to replicate those experienced by statues and ornaments in cities where rainfall and humidity constantly produce an electrolyte layer on the surfaces of bronzes. Ions, acids, and particles of pollutants can dissolve in this layer, resulting in a variety of harsh corrosion processes. The kinetics of corrosion and the properties of the resulting patinas were monitored weekly by electrochemical impedance spectroscopy and open-circuit potential measurements. The sizes and appearances of the corrosion products were monitored and used to estimate the progress of the corrosion, whose crystalline structures were visualized using scanning electron microscopy with energy dispersive spectroscopy, identified by X-ray diffraction, and characterized by spectrocolorimetry. The electrochemical measurements demonstrated that greater damage (in terms of color change and corrosion product formation did not correspond to deficiencies in protection. The mixed-acid solution did not corrode the bronzes, as would be expected from the additive effects of the single acids. The postulated mechanisms of metal dissolution appear to be specific to a particular bronze alloy, with the tin component playing an important role.

  19. 青铜乐器自名研究%A Study of the Names Inscribed on Bronze Musical Instruments

    Institute of Scientific and Technical Information of China (English)

    陈双新

    2001-01-01

    Based on his studies of the bronze musical instruments, the author analyses the inscriptions referring the self-named modifiers and tries to give them new explanations. The study is important to understand the function and values of the bronze musical instruments.

  20. DEGRADATION WORKS OF MONUMENTAL ART CAST BRONZE UNDER THE INFLUENCE OF ENVIRONMENTAL FACTORS

    Directory of Open Access Journals (Sweden)

    Delia NICA-BADEA

    2012-11-01

    Full Text Available Intensive pollution, combined with the lack of conservation of monuments exposed to these environments make the main cause of deterioration of cultural objects to atmospheric corrosion metal. This paper proposes a study of the main factors leading to degradation Bronze alloy, cast bronze monuments exposed to open atmosphere: corrosive environmental factors, stability and products of corrosion of bronze. In general, all corrosion products present on a metal surface are indicated as 'skate', can be composed of single-layer or multilayer products. The paper also includes a case study on the influence of environmental factors on degradation Matthias monument statue in Cluj-Napoca, Romania. Visual inspection of the monument informs us that have white spots, gray, reddish not consistent with the base color green patina, surfaces showing depigmentation, the rain washed areas, crystallization, deposition of air-borne particles.

  1. Preliminary study on corrosion layers of unearthed bronzes relics of Xizhou dynasty, China

    International Nuclear Information System (INIS)

    Engineering barrier for HLW repository is composed of vitrified waste, canister and buffer/backfill material. Assessment of the applicability of metal as candidate materials of canister for HLW has been conducted in some countries.. Many bronze relics in Xizhou Dynasty, China, dated from more than 3000 years ago, have been preserved perfectly. The study on the corrosion of the bronze relics would contribute to the material selection and design of canister for HLW. The corrosion products of ancient bronzes consist of copper carbonate hydrate, lead carbonate, copper oxides etc. The corrosion mechanism of the substrate were mainly characterized by electrochemical corrosion, whereas the corrosion mechanism of surface layers was characterized by direct chemical corrosion and electrochemical corrosion. (author)

  2. The huastec region: a second locus for the production of bronze alloys in ancient mesoamerica.

    Science.gov (United States)

    Hosler, D; Stresser-Pean, G

    1992-08-28

    Chemical analyses of 51 metal artifacts, one ingot, and two pieces of intermediate processed material from two Late Post Classic archeological sites in the Huastec area of Eastern Mesoamerica point to a second production locus for copper-arsenic-tin alloys, copper-arsenic-tin artifacts, and probably copper-tin and copper-arsenic bronze artifacts. Earlier evidence had indicated that these bronze alloys were produced exclusively in West Mexico. West Mexico was the region where metallurgy first developed in Mesoamerica, although major elements of that technology had been introduced from the metallurgies of Central and South America. The bronze working component of Huastec metallurgy was transmitted from the metalworking regions of West Mexico, most likely through market systems that distributed Aztec goods. PMID:17742754

  3. Production of multifilamentary Nb3Sn composites incorporating a high tin bronze

    International Nuclear Information System (INIS)

    The economics and processing methods have been examined for the fabrication of multifilamentary Nb3Sn using a high tin bronze reactive matrix. Four conductor configurations utilizing the high tin bronze were compared with a conventional Cu-13 wt % Sn bronze. The most promising of these designs is potentially 40% lower in cost per ampere meter than the conventional composite. Large hydrostatic extrusion facilities, which are required for the high tin processing, are not presently available in this country but can be made by conversion of conventional presses. They exist in Europe. Experiments were conducted to investigate the applicability of hydrostatic extrusion, and billet components were successfully prepared using the hydrostatic extrusion technique. We have concluded that the economics, availability of facilities and initial fabrication results are favorable for this type of conductor and that the next stage in this program of scale up to extrusion and drawing of 2'' to 3'' diameter composite billets should be undertaken

  4. Practical bronze alloy for Nb3Sn superconductors. Microstructure and cold-workability

    International Nuclear Information System (INIS)

    Copper-Tin (Cu-Sn) bronze alloy is the key material for bronze-processed Nb3Sn superconducting wires. The Osaka Alloying Works in Japan has established a unique melting process for large-scale bronze alloys called the 'Mizuta method'. In this process, the graphite crucible containing hot molten metal is cooled by passing it directly through a water shower. A general mold casting is not needed, so only slight oxidation of the hot molten metal occurs. Since a uni-directional solidification process is used, a very homogeneous tin concentration without severe inverse segregation in the longitudinal direction of the ingots is obtained. In this paper, we investigate the microstructure and mechanical performance details of the practical bronze having Sn concentrations of 14, 15 and 16 mass%. Elongation, 0.2% toughness, Vickers hardness at room temperature, and the limit of continuous cold-drawability as a function of intermediate annealing were studied. Degradation of cold-drawability was excessive, with a rather low annealing temperature of 400degC. We found that numerous fine precipitates appeared at the intra- and inter-alpha grains after low-temperature annealing. The transmission electron microstructure analysis revealed that those precipitates were the delta phase (Cu41Sn11). The delta precipitates may behave as a pinning site of the slip motion for the plastic deformation of bronze alloys. We have to re-recognize that the intermediate annealing temperature is a very important parameter for avoiding wire breakage during the industrial production of bronze-processed Nb3Sn superconductors. (author)

  5. Ancient bronze horse muzzles of the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    Garcés Estallo, Ignasi

    2011-12-01

    Full Text Available Horse muzzles and Bronze muzzles are unique equestrian tools that have been referred to in scattered accounts throughout history. Nevertheless, the majority of these objects have received short descriptions and an overall study is still missing. The lack of a comprehensive study hinges on the over looked importance of these items and the superficial manner that have characterized their documentation. Both these reasons have limited observations on chronology and archaeological investigation. The recent identification of new unpublished exemplars among the Museums’ collections in Barcelona and Lleida has encouraged the authors of this paper to start a new study dedicated to these objects. Starting from a catalogue inclusive of all muzzles and muzzles currently known in the Iberian Peninsula, an attempt will be made to propose an accurate description, typological classification and, for some of the items, a revision of the decorative scenes that have marked their place in bronze horse muzzle and muzzle chronology. The formal development and the chronological framework here proposed refer to those of the exemplars found in Greece and in Italy. The broadening of the geographical area will allow reconsideration of those social phenomena that have in the past determined the diffusion of elements in horse tack throughout most of the western Peninsula in the Mediterranean.

    Los bozales y las muserolas en bronce para caballo constituyen unos excepcionales complementos ecuestres cuyo conocimiento se encuentra disperso en una extensa bibliografía. De muchos ejemplares apenas se ha publicado una breve descripción y nunca hasta el presente han sido objeto de un estudio monográfico, quizás por el desaliento que produce el desconocimiento de su procedencia en unos casos, o la superficial noticia del contexto de aparición en la mayoría de ellos, hecho que ha limitado las consideraciones cronológicas y de asociación. La identificación de nuevos

  6. Dynamic characteristics of Great Bronze Buddha of Kamakura using microtremor

    International Nuclear Information System (INIS)

    The second largest bronze Buddha in Japan built in around 1250AD at Kamakura immediately above the focal region of the 1923 Kanto earthquake. Great Buddha of Kamakura has still remained basically its original shape, though it has been suffered several natural disasters as losing its hall. Especially, although the 1703 and 1923 Kanto earthquakes caused settlement and sliding of the basement over 0.3 m., the body has been not suffered serious damage. This statue was casted in order from the bottom with many joints. The joint between the head and the body was noticed because it is reinforced by FRP, Fiber Reinforced Plastic, at the time of the last major repair in 1961. And ingenuity was exercised to fence off the earthquake motion over 400 Gal with sliding the body on the basement, to reduce the load for the neck during earthquake. This is the first example of the earthquake isolation system for cultural properties in Japan. Over 50 years passed after the during earthquake motion, microtremor measurement was conducted. As a result of the primary investigation in 2009, the surrounding ground was estimated that liquefaction was occurred at the front and right sides of the basement and the basement suffered damage as settlement. However, it is considered that the propagation of the earthquake motion for the statue was interrupted because of the liquefaction. Thus, it seems that the damage for the statue itself was prevented because of namely the natural isolation system. Additional y in 2013 microtremor of the statue itself was measured for making clear the connection status between the body and the head.

  7. Spinal arthritis and physical stress at Bronze Age Harappa.

    Science.gov (United States)

    Lovell, N C

    1994-02-01

    This study examines joint changes in the vertebral skeleton in human remains excavated in 1987 and 1988 at Bronze Age Harappa, an urban center of the Indus Valley civilization. The sample consists of 23 complete skeletons from primary burial context, the partial remains of more than 69 other individuals, and hundreds of skeletal elements from secondary context, totalling 3,084 vertebral joint margins and articular surfaces. Marginal bone proliferation, pitting of articular surfaces, eburnation, and ankylosis were scored macroscopically for vertebral body margins and surfaces and posterior apophyseal facet joints. Marginal lipping is far more prevalent on the vertebral bodies than on the apophyseal facets and surface pitting is also more frequent on vertebral bodies although its expression is relatively low overall. Cervical vertebrae in this sample exhibit the same amount of marginal new bone and much more surface pitting of the vertebral bodies than do either thoracic or lumbar vertebrae; the cervical segment also exhibits the most severe expressions of both types of lesions. In addition, although the frequencies of cervical and lumbar posterior facet involvement are similar, the cervical facets exhibit much more severe lipping as well as the only cases of eburnation and ankylosis. Pitting of the posterior facets is most common in the lumbar segment, but the cervical examples are the only severe cases. It is proposed that the severe joint changes in the cervical spine result from trauma, perhaps accumulated microtrauma from activity stresses. There are no age or sex associated patterns in the frequency of arthritis although this result may be influenced by the small proportions of the total sample for which age and sex could be determined. PMID:8147433

  8. Archaeological Geophysics at the San Marcos Pueblo, New Mexico, USA

    Science.gov (United States)

    Grimes, K.; Joiner, C. J.; Musa, D.; Allred, I.; Delhaye, R. P.; Zorin, N.; Feucht, D. W.; Johnston, G.; Pellerin, L.; McPhee, D.; Ferguson, J. F.

    2013-12-01

    The students and faculty of the Summer of Applied Geophysical Experience (SAGE) geophysical field course have studied the San Marcos Pueblo (LA 98) since 2004. This activity has provided instruction in near-surface geophysics and research into the application of geophysical techniques to southwestern archaeological problems. Our study site, the San Marcos Pueblo, is a classical and colonial period (1200-1680) pueblo that was once one of the largest communities in the southwest. Previous SAGE publications have discussed the discovery of archaeological features, the underlying geology and hydrological conditions. This study focuses on the interpretation of 'El Mapo Grande', 150 m X 150 m, high-resolution (0.5 m) maps of magnetic and electrical properties and 12 seismic refraction lines. The map covers room block, plaza and midden areas as well as areas where colonial period metallurgical activities were known to have occurred. We acquired magnetic, electromagnetic (EM), and ground-penetrating radar (GPR) data in 30 m X 30 m quads producing geophysical maps of each quad (2 or 3 produced each year). Total magnetic field measurements were made with a Geometrics cesium vapor magnetometer, GPR data collected using a Sensors and Software 250 MHz radar were on 0.5 m spaced lines, and EM data were acquired with a Geonics EM-31 on 1 m spaced lines. Seismic data were collected on interconnected lines with 0.5 m receiver and 3 m source interval. El Mapo Grande shows anomalies correlated among the diverse physical properties that were mapped. The edges of strong magnetic anomalies correlate with areas of high GPR scattering possibly associated with rocky floors under room blocks. Areas of high magnetic response are associated with hill-slope erosion channels and plumes of debris in the plaza to the south that are apparently washing down from the metallurgical sites near room blocks. EM data display a good correlation with the magnetic map. Debris channels and plumes are more

  9. Neutron resonance capture and neutron diffraction analysis of Roman bronze water taps

    International Nuclear Information System (INIS)

    Parts of four Roman bronze water taps, excavated in The Netherlands consisting of two cylinders and two cylinder housings, were nondestructively investigated by neutron resonance capture analysis and by time-of-flight neutron diffraction. The two complementary neutron methods have been, for the first time, combined for providing a comprehensive alloy characterization of intact, undisturbed archaeological bronze objects. Bulk chemical analyses and phase analyses of the copper alloys were carried out in order to establish relations and differences among the taps, and to address questions of standardization and fabrication. (author)

  10. Vegetation reconstruction of Bronze Age by using microscopic structure of charcoals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The microscopic structure of charcoals was determined in two sites of Bronze Age, Chifeng area by using the scanning electronic microscope. The results showed that these charcoals are all timbers of Mongolian oak (Quercus mongolica). It has powerful climatic indicative significance. Based on the assemblage of pollen composition, their eco-climatic index and character of community, the vegetation reconstruction of Bronze Age was obtained. The reconstruction showed that the zonal vegetation was Mongolian oak forest and Chinese pine forest in the loess hills in the Chifeng area, which suggested that the climatic condition was warmer and wetter at that time than present time.

  11. Nomadic pastoralism in the Early Bronze Age of the central Balkans evaluation of background knowledge

    Directory of Open Access Journals (Sweden)

    Porčić Marko

    2008-01-01

    Full Text Available The aim of the paper is to examine background knowledge about the orga­nizational properties of mobile pastoral groups in order to assess the likelihood of the existence of pastoral nomads in the Early Bronze Age in the central Balkans. The patterning found by A. L. Johnson (2002 is taken as a point of departure for the cross-cultural analysis conducted in this study. Johnson’s findings are in the main corroborated. Acquired knowledge about the workings of pastoral societies suggests that highly mobile pastoral groups should not be expected in the Early Bronze Age of the central Balkans.

  12. Multielement analysis of archaic Chinese bronze and antique coins by fast neutron activation analysis

    International Nuclear Information System (INIS)

    Samples of archaic bronze were investigated by fast neutron activation analysis using both the absolute and relative method. The components Cu, Zn, Sn and Pb were determined quantitatively. For nondestructive analysis of antique Chinese coins the samples had to be irradiated. The activation reactions, the evaluation of the elemental concentrations and the accuracy of the results are discussed. The data were corrected for γ-ray self-absorption in the samples and summing of coincident γ-rays in the detector. According to reported typical compositions of Chinese bronze from different dynasties, the age of the samples has been derived from the results obtained. (author) 18 refs.; 3 figs.; 7 tabs

  13. Elemental analysis of ancient Chinese bronze artifacts with external-beam PIXE

    International Nuclear Information System (INIS)

    External-beam PIXE has been applied for the determination of the elemental composition of ancient Chinese bronze artifacts. Characteristic x-ray spectra from the samples bombarded with protons of 3 MeV have been measured with a HPGe detector. At each sample three spots were irradiated per run. Results of measurements on three fragments of bronze drinking vessels and helmet of Chinese ancient Chou and Shang dynasties (17th-8th century B.C.) are presented. To check the analytical method, we have also made measurements on the elemental composition of some modern coins. The results are discussed. (author)

  14. O bronze final na região de Mértola

    OpenAIRE

    BARROS, Pedro de

    2012-01-01

    Mértola fica localizada num local com boa defensibilidade, no final do longo estuário do Rio Guadiana no Sudoeste Peninsular entre uma peneplanicíe e os vales encaixados, onde as linhas de água subsidiárias têm o seu percurso. A ocupação do Bronze Final de Mértola é revelada pela presença de cerâmica com ornatos brunidos, formas cerâmicas manuais, cerâmica frequentemente designada "tipo Carambolo" e um exemplar de foice em bronze do "tipo Rocanes". Apesar de serem poucos os elementos, estes r...

  15. Bronze Age moss fibre garments from Scotland – the jury’s out

    OpenAIRE

    Harris, Susanna; Gleba, Margarita

    2015-01-01

    In the light of recent discoveries of early to middle Bronze Age burials with mats and fibrous material in Scotland, for example at Langwell farm and Forteviot, it was deemed timely to re-evaluate earlier finds of this period, several of which were discovered and initially reported on nearly a century ago. As part of this research it was noted that three Bronze Age finds from the old literature were reported as clothing or shrouds made of hair moss (Polytrichum commune). Three of these are r...

  16. Corrosion Behaviour of Alpha Phase Aluminium Bronze Alloy in Selected Environments

    OpenAIRE

    Oluwayomi BALOGUN; Joseph BORODE; Kenneth ALANEME; Michael BODUNRIN

    2014-01-01

    This research investigated the corrosion behaviour of aluminium (8 wt %) bronze alloys produced via sand casting in acidic, alkaline, and marine environments. The aluminium bronze was produced from aluminium (6063) alloy and copper scraps by sand casting according to European standard specification (UNS. C61400-CuAl8), after which they were cut into smaller sizes and immersed in the selected corrosive media for corrosion test investigation. H2SO4, NaCl, NaOH, and HCl of 0.1 M, 0.2 M, 0.3 M, 0...

  17. Craftmanship, Production and Distribution of Metalwork in the Early and Middle Northern Bronze Age

    DEFF Research Database (Denmark)

    Nørgaard, Heide Wrobel

    Workshops and their sphere of influence is an important factor in the identification of social groups who are related to what we term workshop. Here the specialization within the workshop based on certain forms and behaviours can be linked to the knowledge of social groups. Statements about the...... possible to compare these traits between different bronze objects. Using a group of bronze objects who are already critically analyzed with regard to the formal characteristics gives a unique opportunity to recognize the workshops and their distribution areas and will be the base of the project....

  18. Hacia un marco conceptual para repensar la accesibilidad cultural

    Directory of Open Access Journals (Sweden)

    Fernando Landini

    2014-02-01

    Full Text Available La accesibilidad de la población al sistema de salud constituye una de las principales preocupaciones de las políticas sanitarias. No obstante, son pocos los trabajos que profundizan conceptualmente en dicha noción. La mayor parte de ellos diferencia entre disponibilidad, accesibilidad y aceptabilidad, o entre accesibilidad geográfica, financiera, administrativa y cultural. En el presente trabajo se discute y analiza la noción de accesibilidad, definiéndosela como un proceso de articulación conflictiva entre demanda y oferta en salud. A la vez, se focaliza en la noción de accesibilidad cultural, la cual es repensada como una interfaz social, es decir, como un espacio conflictivo en el que se articulan marcos de sentido diferentes, en este caso el de los profesionales y el de los pacientes. Esto permite abordar los procesos complejos de apropiación, traducción y reconfiguración de los conocimientos y recomendaciones que se dan en este vínculo.

  19. Identidad, escritura, performance: Marco Paolini, actor y autor

    Directory of Open Access Journals (Sweden)

    Simone Soriani

    2016-01-01

    Full Text Available Marco Paolini es uno de los más representativos actores y autores del llamado "teatro di narrazione". El presente artículo pretende acercarse a algunos aspectos centrales de su poética en tanto actor y escritor, tales como los complejos y articulados procesos a través de los cuales llega a un (más o menos definitivo texto escrito; la fuerte relación que establece entre él y su público, a quien Paolini siempre se dirige consciente y explícitamente con gags y "bromas" en ocasiones tomados de la tradición del teatro popular italiano; o el "lenguaje del cuerpo" que Paolini pone en práctica en el escenario y en las páginas de sus libros publicados, en el que (de un modo personal mezcla el italiano, dialectos venecianos y ecos de poetas y escritores de la tradición literaria italiana.

  20. El teatro im/posible en TV de Marco Paolini

    Directory of Open Access Journals (Sweden)

    Massimo Puliani

    2016-01-01

    Full Text Available En el contexto cultural italiano, la comercializacion de obras de teatro ha dejado de ser un producto orientado a un consumidor concreto para transformarse en muchos casos en un producto de largo consumo. De hecho, en las últimas décadas cadenas de televisión, editoriales, revistas especializadas y medios de comunicación escritos han estado editando y comercializando obras de teatro de manera satisfactoria y con una notable acogida de público y crítica. En este sentido, la obra editada y comercializada de Marco Paolini ha tenido (y tiene un papel fundamental. La edición televisada de espectáculos como Il racconto del Vajont, Miserabili, Il Milione o Ausmerzen. Vite indegne di essere vissute, son ejemplo de como un espectáculo teatral puede perfectamente tener cabida en un contexto televisivo, además de poder entenderse como un inestimable punto de partida para una reflexión sobre las posibilidades que ofrece la adaptación a un medio televisado.

  1. Kinkaleri : teater peab tekitama küsimuse, mitte andma vastuse / Marco Mazzoni ; interv. Andres Keil

    Index Scriptorium Estoniae

    Mazzoni, Marco

    2008-01-01

    1995. a. Itaalias asutatud kuuest kunstnikust - Matteo Bambi, Luca Camilletti, Massimo Conti, Marco Mazzoni, Gina Monaco ja Cristina Rizzo - koosnevast eksperimentaalteatrist Kinkaleri ja Kanuti Gildi saalis 7. ja 8. nov. esiettekandele tulevast lavastusest "Yes, Sir!"

  2. Strangers in a strange land: Egyptians in southern Palestine during the Bronze Age

    Directory of Open Access Journals (Sweden)

    Rachael Sparks

    2002-10-01

    Full Text Available When the Institute of Archaeology was formally established in 1937, it became responsible for housing Sir Flinders Petrie’s collection of archaeological material from Palestine. This unique inheritance has great value as a research collection, as its curator demonstrates here in her discussion of interaction between Egypt and Palestine in the Bronze Age.

  3. La médaille de bronze du CNRS à un physicien clermontois

    CERN Document Server

    2005-01-01

    Evey year, the National center for scientific research (CNRS), rewards around fifty of searchers at various stages of their career. The bronze medal rewards the first work of a searcher, making of him a specialist in his field; Philippe Crochet was awarded this medal

  4. Reproducible nuclear reactions upon reaction of deuterium with tungsten oxide bronze

    International Nuclear Information System (INIS)

    Investigators of anomalous nuclear phenomena in condensed media have not been able to achieve 100% reproducibility of results on observation of emission of nuclear radiation. All these experiments were carried out with solids based on metal-hydrogen systems, neither the structure nor the crystallographic orientation of which can be controlled. In contrast to all the experiments performed so far, in order to achieve a high level of reproducibility the authors used fundamentally new materials as the objects of investigation: single crystals of tungsten oxide bronzes, nonstoichiometric compounds with general formula NaxWO3. As the working surface the authors used the (001) face of the crystal, perpendicular to which the channels of the rigid W-O sublattice are located. Alkali metal cations are located in these channels and can move through them. Depending on the alkali metal content in the tungsten oxide bronze, due to the variation in the valence state of the tungsten, oxide bronzes can vary over very broad limits. This allows the authors to create structures in the crystal with high composition in gradients and gradients in properties due to them and, in particular, to also use an electric field to control the movement of ions in the crystal. Using electrochemical methods (anodic treatment in salt melts, aqueous solutions, and under vacuum), sodium can be extracted from the channels in the surface layer of the bronze crystal and substituted by hydrogen (deuterium) ions

  5. Study on surface properties of gilt-bronze artifacts, after Nd:YAG laser cleaning

    International Nuclear Information System (INIS)

    As numerous pores are formed at plating gilt-bronze artifacts, the metal underlying the gold is corroded and corrosion products are formed on layer of gold. Through this study, the surfaces of gilt-bronze are being investigated before and after the laser irradiation to remove corrosion products of copper by using Nd:YAG laser. For gilt-bronze specimens, laser and chemical cleaning were performed, and thereafter, surface analysis with SEM-EDS, AFM, and XPS were used to determine the surface characteristics. Experimental results show that chemical cleaning removes corrosion products of copper through dissolution but it was not removed uniformly and separated the metal substrate and the gold layer. Nevertheless, through laser cleaning, some of the corrosions were removed with some damaged areas due to certain conditions and brown residues remained. Brown residues were copper corrosion products mixed with soil left within the gilt layer. It was due to surface morphology of uneven and rough gilt layer. Hence, they did not react effectively to laser beams, and thus, remained as residues. The surface properties of gilt-bronze should be thoroughly investigated with various surface analyses to succeed in laser cleaning without damages or residues.

  6. Study on surface properties of gilt-bronze artifacts, after Nd:YAG laser cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyeyoun [Division of Restoration Technology, National Research Institute of Cultural Heritage, Daejeon (Korea, Republic of); Cho, Namchul, E-mail: nam1611@hanmail.net [Department of Cultural Heritage Conservation Science, Kongju National University, Gongju, 314-701 (Korea, Republic of); Lee, Jongmyoung [Laser Engineering Group, IMT Co. Ltd, Gyeonggi (Korea, Republic of)

    2013-11-01

    As numerous pores are formed at plating gilt-bronze artifacts, the metal underlying the gold is corroded and corrosion products are formed on layer of gold. Through this study, the surfaces of gilt-bronze are being investigated before and after the laser irradiation to remove corrosion products of copper by using Nd:YAG laser. For gilt-bronze specimens, laser and chemical cleaning were performed, and thereafter, surface analysis with SEM-EDS, AFM, and XPS were used to determine the surface characteristics. Experimental results show that chemical cleaning removes corrosion products of copper through dissolution but it was not removed uniformly and separated the metal substrate and the gold layer. Nevertheless, through laser cleaning, some of the corrosions were removed with some damaged areas due to certain conditions and brown residues remained. Brown residues were copper corrosion products mixed with soil left within the gilt layer. It was due to surface morphology of uneven and rough gilt layer. Hence, they did not react effectively to laser beams, and thus, remained as residues. The surface properties of gilt-bronze should be thoroughly investigated with various surface analyses to succeed in laser cleaning without damages or residues.

  7. Dating Archaeological Copper/Bronze Artifacts by Using the Voltammetry of Microparticles

    OpenAIRE

    Doménech-Carbó, Antonio; Doménech-Carbó, Maria Teresa; Capelo, Sofia; Pasíes, Trinidad; Martínez-Lázaro, Isabel

    2014-01-01

    A method for dating copper/bronze archaeological objects aged in atmospheric environments is proposed based on the specific signals for cuprite and tenorite corrosion products measured through the voltammtry of microparticles method. The tenorite/cuprite ratio increased with the corrosion time and fitted to a potential law that yielded a calibration curve usable for dating purposes.

  8. Techniques employed in making ancient thin-walled bronze vessels unearthed in Hubei Province, China

    Science.gov (United States)

    Li, Yang; Wu, Taotao; Liao, Lingmin; Liao, Chengwei; Zhang, Lang; Chen, Guantao; Pan, Chunxu

    2013-06-01

    In this paper, two ancient thin-walled bronze vessels unearthed in Anlu County of Hubei Province, China, were studied systematically by using optical microscopy (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), electron backscatter diffraction (EBSD) and nanoindentation system, and also we calculated the Sn diffusion in a Cu substrate based upon the substitutional mechanism at high temperature. The results indicated that the vessels were possibly fabricated using the following processes: (1) alloying the high-tin Cu-Sn bronze; (2) casting the preliminary shape of the vessels; (3) forging the vessels in the temperature range of 586-798 ∘C; (4) simply wiping tinning on the surface of the vessel at high temperature; (5) quenching the vessels to room temperature; and (6) at last, grinding and polishing the surface of the vessels. It seems that the present thin-walled bronze vessels provide an evidence of the spread of thin-walled high-tin bronze technology in China and its surrounding regions.

  9. Isotopic dietary reconstruction of humans from Middle Bronze Age Lerna, Argolid, Greece

    NARCIS (Netherlands)

    Triantaphyllou, S.; Richards, M. P.; Zerner, C.; Voutsaki, S.

    2008-01-01

    This study presents the results of a carbon and nitrogen stable isotope analysis of 39 human bone and 8 animal samples from Middle Bronze Age (or Middle Helladic, MH, ca. 2100-1700 BC) Lerna, Greece. The isotopic data indicate that the humans had a C-3 terrestrial diet while certain individuals appe

  10. Celestial Symbolism in Central European Later Prehistory - Case Studies from the Bronze Age Carpathian Basin

    Science.gov (United States)

    Pásztor, Emília

    It is commonly held that the sun played a particularly important cultural role in later prehistoric Europe. The rise of a general European sun cult has even been suggested for the Bronze Age. During this period, the increasing use of special symbols assumed to represent the sun is easily discernible on different types of archaeological finds.

  11. Antibacterial drugs as corrosion inhibitors for bronze surfaces in acidic solutions

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • All four investigated antibacterial drugs act as corrosion inhibitors for bronze surface. • In the presence of antibiotics, a 3RC electric circuit simulates the corrosion system. • The electrochemical results indicate as best inhibitors Doxy, followed by Strepto. • HOMO–LUMO energy gap increases in the order: Doxy > Strepto > Cipro > Amoxi. • The thin protective film on bronze is reinforced by the presence of the antibiotics. - Abstract: The present study is aiming to investigate the effect of four antibiotics (amoxicillin, ciprofloxacin, doxycycline and streptomycin,) belonging to different classes of antibacterial drugs on bronze corrosion in a solution simulating an acid rain (pH 4). Due to their ability to form protective films on the metal surface, the tested antibiotics act as corrosion inhibitors for bronze. The antibiotics were tested at various concentrations in order to determine the optimal concentration range for the best corrosion inhibiting effect. In evaluating the inhibition efficiency, polarization curves, electrochemical impedance spectroscopy, SEM and XPS measurements were used. Moreover, a correlation between the inhibition efficiency of some antibacterial drugs and certain molecular parameters was determined by quantum chemical computations. Parameters like energies EHOMO and ELUMO and HOMO–LUMO energy gap were used for correlation with the corrosion data

  12. Electrodeposition and corrosion resistance of nanocrystalline white bronze (CuSn) coatings

    NARCIS (Netherlands)

    Hovestad, A.; Lekka, M.; Willemsen, R.M.R.; Tacken, R.A.; Bonora, P.L.

    2008-01-01

    For jewellery applications electroplated white bronze (CuSn) was investigated as undercoating for noble metal finishes as alternative to nickel. A strongly acidic plating bath was developed with an organic additive to suppress hydrogen evolution and obtain bright coatings. An electrochemical study o

  13. Upward Sweeps of Empire and City Growth Since the Bronze Age

    OpenAIRE

    Chris Chase-Dunn; Alexis Alvarez; Hiroko Inoue; Richard Niemeyer; Anders Carlson; Ben Fierro; Kirk Lawrence

    2006-01-01

    Abstract: This paper uses quantitative estimates of the sizes of cities and empires to tentatively identify upward sweeps in which uniquely large cities and empires emerged in the Central Political/military network since the Bronze Age, and it formulates a causal model to explain both the cyclical rise and fall of cities and empires and the upward sweep

  14. Characterisation of a Proto-historic bronze collection by micro-EDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Elin, E-mail: elin@itn.pt [IST/ITN, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953 Sacavém (Portugal); CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Araújo, M. Fátima [IST/ITN, Instituto Superior Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953 Sacavém (Portugal); Silva, Rui J.C. [CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Vilaça, Raquel [CEAUCP-FCT, Instituto de Arqueologia, Departamento de História, Arqueologia e Artes, Faculdade de Letras, Universidade de Coimbra, Palácio de Sub-Ripas, 3000-395 Coimbra (Portugal)

    2013-02-01

    Highlights: ► A collection of Proto-historic metal artefacts was analysed by micro-EDXRF. ► Composition of major and minor elements has been determined. ► Artefacts were manufactured in a bronze alloy with a low impurity pattern. ► The alloy shows parallels with indigenous Late Bronze Age Iberian productions. -- Abstract: Studies concerning European Proto-historic metallic artefacts can provide important clues about technological transfers during a period of time characterised by diverse cultural interactions. A collection of Proto-historic metallic artefacts from Medronhal (western Iberian Peninsula) composed by rings, bracelets and a fibula related to different cultural affiliations were investigated by micro-EDXRF to provide a major and a minor elemental characterisation. Results show that the Medronhal collection was manufactured in a Cu–Sn alloy (binary bronze) with similar Sn contents among the various types of artefacts and a low impurity pattern. Results of the type and quality of metal were compared to other artefact collections to infer about metallurgical parallels. Strong parallels with indigenous Late Bronze Age Iberian metallurgical productions were found.

  15. Cold Spraying of Cu-Al-Bronze for Cavitation Protection in Marine Environments

    Science.gov (United States)

    Krebs, S.; Gärtner, F.; Klassen, T.

    2015-01-01

    Traveling at high speeds, ships have to face the problem of rudder cavitation-erosion. At present, the problem is countered by fluid dynamically optimized rudders, synthetic, and weld-cladded coatings on steel basis. Nevertheless, docking and repair is required after certain intervals. Bulk Cu-Al-bronzes are in use at ships propellers to withstand corrosion and cavitation. Deposited as coatings with bulk-like properties, such bronzes could also enhance rudder life times. The present study investigates the coating formation by cold spraying CuAl10Fe5Ni5 bronze powders. By calculations of the impact conditions, the range of optimum spray parameters was preselected in terms of the coating quality parameter η on steel substrates with different temperatures. As-atomized and annealed powders were compared to optimize cavitation resistance of the coatings. Results provide insights about the interplay between the mechanical properties of powder and substrate for coating formation. Single particle impact morphologies visualize the deformation behavior. Coating performance was assessed by analyzing microstructures, bond strength, and cavitation resistance. These first results demonstrate that cold-sprayed bronze coatings have a high potential for ensuring a good performances in rudder protection. With further optimization, such coatings could evolve towards a competitive alternative to existing anti-cavitation procedures.

  16. The Agro Pontino region, refuge after the Early Bronze Age Avellino eruption of Mount Vesuvius, Italy?

    NARCIS (Netherlands)

    C. Bakels; J. Sevink; W. Kuijper; H. Kamermans

    2015-01-01

    In recent years it was discovered that the Middle to Late Holocene infi ll of the Agro Pontino graben (Central Italy) held a tephra layer originating from the Avellino eruption of the Vesuvius volcano. The eruption is dated to 1995 ± 10 calBC and took therefore place during the Early Bronze Age. Thi

  17. 76 FR 40402 - Matthews International Corporation, Bronze Division, Kingwood, WV; Notice of Negative...

    Science.gov (United States)

    2011-07-08

    ..., Kingwood, WV; Notice of Negative Determination on Reconsideration On January 28, 2011, the Department of..., 2011 (76 FR 7584). Workers were engaged in the production of cast bronze memorial products. The initial investigation resulted in a negative determination based on the findings that, during the relevant period,...

  18. Antibacterial drugs as corrosion inhibitors for bronze surfaces in acidic solutions

    Energy Technology Data Exchange (ETDEWEB)

    Rotaru, Ileana [Department of Chemical Engineering, “Babes-Bolyai” University, 11 Arany-Janos St., 400028 Cluj-Napoca (Romania); Varvara, Simona, E-mail: svarvara@uab.ro [Department of Exact Sciences and Engineering, “1 Decembrie 1918” University, 11-13 Nicolae Iorga St., 510009 Alba Iulia (Romania); Gaina, Luiza [Department of Chemical Engineering, “Babes-Bolyai” University, 11 Arany-Janos St., 400028 Cluj-Napoca (Romania); Muresan, Liana Maria, E-mail: limur@chem.ubbcluj.ro [Department of Chemical Engineering, “Babes-Bolyai” University, 11 Arany-Janos St., 400028 Cluj-Napoca (Romania)

    2014-12-01

    Graphical abstract: - Highlights: • All four investigated antibacterial drugs act as corrosion inhibitors for bronze surface. • In the presence of antibiotics, a 3RC electric circuit simulates the corrosion system. • The electrochemical results indicate as best inhibitors Doxy, followed by Strepto. • HOMO–LUMO energy gap increases in the order: Doxy > Strepto > Cipro > Amoxi. • The thin protective film on bronze is reinforced by the presence of the antibiotics. - Abstract: The present study is aiming to investigate the effect of four antibiotics (amoxicillin, ciprofloxacin, doxycycline and streptomycin,) belonging to different classes of antibacterial drugs on bronze corrosion in a solution simulating an acid rain (pH 4). Due to their ability to form protective films on the metal surface, the tested antibiotics act as corrosion inhibitors for bronze. The antibiotics were tested at various concentrations in order to determine the optimal concentration range for the best corrosion inhibiting effect. In evaluating the inhibition efficiency, polarization curves, electrochemical impedance spectroscopy, SEM and XPS measurements were used. Moreover, a correlation between the inhibition efficiency of some antibacterial drugs and certain molecular parameters was determined by quantum chemical computations. Parameters like energies E{sub HOMO} and E{sub LUMO} and HOMO–LUMO energy gap were used for correlation with the corrosion data.

  19. Da escuridão para a luz: origem e extensão da Bíblia em braille no Brasil. Dissertação

    Directory of Open Access Journals (Sweden)

    Marcos Adriano Lovera

    2013-12-01

    Full Text Available LOVERA, Marcos Adriano. Da escuridão para a luz: origem e extensão da Bíblia em braille no Brasil. Dissertação (Mestrado 2013. 176p. - Pontifícia Universidade Católica de Minas Gerais, Programa de Pós-graduação em Ciências da Religião, Belo Horizonte

  20. Randomised controlled trials of staged teaching for basic life support. 1. Skill acquisition at bronze stage.

    Science.gov (United States)

    Assar, D; Chamberlain, D; Colquhoun, M; Donnelly, P; Handley, A J; Leaves, S; Kern, K B

    2000-06-01

    We have investigated a method of teaching community CPR in three stages instead of in a single session. These have been designated bronze, silver, and gold stages. The first involves only opening of the airway and chest compression with back blows for choking, the second adds ventilation in a ratio of compressions to breaths of 50:5, and the third is a conversion to conventional CPR. In a controlled randomised trial of 495 trainees we compared the performance in tests immediately after instruction of those who had received a conventional course and those who had had the simpler bronze level tuition. The tests were based on video recordings of simulated resuscitation scenarios and the readouts from recording manikins. Differences occurred as a direct consequence of ventilation being required in one group and not the other, some variation probably followed from unforeseen minor changes in the way that instruction was given, whilst others may have followed from the greater simplicity in the new method of training. A careful approach was followed by slightly more trainees in the conventional group whilst appreciably more in the bronze group remembered to shout for help (44% vs. 71%). A clear advantage was also seen for bronze level training in terms of those who opened the airway as taught (35% vs. 56%), for checking breathing (66% vs. 88%), and for mentioning the need to phone for an ambulance (21% vs. 32%). Little difference was observed in correct or acceptable hand position between the conventional group who were given detailed guidance and the bronze group who were instructed only to push on the centre of the chest. The biggest differences related to the number of compressions given. The mean delay to first compression was 63 s and 34 s, and the mean duration of pauses between compressions was 16 s and 9 s, respectively. Average performed rates were similar in the two groups, but more in the conventional group compressed too slowly whereas more in the bronze group

  1. Grain refinement of bronze alloy by equal-channel angular pressing (ECAP and its effect on corrosion behaviour

    Directory of Open Access Journals (Sweden)

    M.M. Sadawy

    2016-08-01

    Full Text Available The corrosion behaviour of bronze alloy prepared by equal channel angular pressing (ECAP was investigated in 3.5 wt. % NaCl solution. Immersion corrosion tests and different electrochemical techniques were carried out. The results showed that ECAPed bronze samples exhibited higher corrosion resistance compared with the as-cast alloy and the passive current density decreased with increasing number of passes. Moreover, the morphology of alloys indicated that the corrosion damage on the surface of ECAPed bronze was smooth and uniform while the as-cast alloy suffered from selective corrosion.

  2. Calculation of vanadium bronze NaV6O5 electron spectrum by the semiempiric MO LCAO method

    International Nuclear Information System (INIS)

    The electronic spectrum of an oxide vanadium bronze of the type NaV6O15 has been calculated by a modified MVG method, while taking into consideration the Madelung potential and the electrical neutrality of the crystal lattice. Presented are contributions to the crystalline potential across the bronze nodes, made by sublattices of ions V, O, and Na in equivalent positions. It is the comparison of the spectra calculated by the MO LKAO method and in the purely ionic approximation with the experimental ones that enables one to assess more exactly the degree of ionic bonds in the bronze

  3. Sciades herzbergii oxidative stress biomarkers: an in situ study of an estuarine ecosystem (São Marcos' Bay, Maranhão, Brazil

    Directory of Open Access Journals (Sweden)

    Raimunda Nonata Fortes Carvalho-Neta

    2010-01-01

    Full Text Available In order to study the effects of environmental contamination on wild fish, sites were sampled in São Marcos' Bay. The first is located near the ALUMAR/ALCOA port, a potentially contaminated area. The second, located near the Coqueiro beach, was used as a reference area. The activity of antioxidant defence catalase (CAT and glutathione S-transferase (GST in S. herzbergii was compared with the biometric data and gonadosomatic index (GSI. The result showed that GSI decreased significantly in females (pO objetivo desse trabalho foi estudar os efeitos da contaminação ambiental em peixes amostrados em dois locais da Baía de São Marcos. O primeiro ponto está localizado próximo ao porto da ALUMAR/ALCOA, considerado como uma área potencialmente contaminada. O segundo ponto, situado na praia do Coqueiro, foi usado como uma área de referência. Dados da atividade da enzima de defesa antioxidante catalase (CAT e da glutationa S-transferase (GST em S. herzbergii foram comparados com os dados biométricos e o índice gonadossomático (GSI. Resultados mostraram que o GSI diminuiu significativamente em fêmeas (p <0.05 no local contaminado. A atividade da CAT foi mais alta nos peixes do local contaminado. Uma diferença significativa foi observada na atividade de GST de S. herzbergii no local contaminado e no local de referência (p <0.05. GSI possibilitou uma nova abordagem quanto à natureza da resposta de destoxificação nessa espécie de bagre porque este índice não apresentou correlação com as enzimas no local potencialmente contaminado, mas apresentou no local de referência. Assim, sugere-se que a boa correlação da GST/CAT e GSI poderia estar relacionada à reprodução dos animais no local de referência, mas não no local potencialmente contaminado. Se esse for o caso, pode-se concluir que GST/CAT e GSI podem ser utilizados como bons biomarcadores para avaliar contaminação aquática.

  4. Role of Lysosomes in Silica-Induced Inflammasome Activation and Inflammation in Absence of MARCO

    Directory of Open Access Journals (Sweden)

    Rupa Biswas

    2014-01-01

    Full Text Available MARCO is the predominant scavenger receptor for recognition and binding of silica particles by alveolar macrophages (AM. Previously, it was shown that mice null for MARCO have a greater inflammatory response to silica, but the mechanism was not described. The aim of this study was to determine the relationship between MARCO and NLRP3 inflammasome activity. Silica increased NLRP3 inflammasome activation and release of the proinflammatory cytokine, IL-1β, to a greater extent in MARCO−/− AM compared to wild type (WT AM. Furthermore, in MARCO−/− AM there was greater cathepsin B release from phagolysosomes, Caspase-1 activation, and acid sphingomyelinase activity compared to WT AM, supporting the critical role played by lysosomal membrane permeabilization (LMP in triggering silica-induced inflammation. The difference in sensitivity to LMP appears to be in cholesterol recycling since increasing cholesterol in AM by treatment with U18666A decreased silica-induced NLRP3 inflammasome activation, and cells lacking MARCO were less able to sequester cholesterol following silica treatment. Taken together, these results demonstrate that MARCO contributes to normal cholesterol uptake in macrophages; therefore, in the absence of MARCO, macrophages are more susceptible to a greater inflammatory response by particulates known to cause NLRP3 inflammasome activation and the effect is due to increased LMP.

  5. Selection of the temperature of casting the bronzes to plaster moulds

    Directory of Open Access Journals (Sweden)

    B. Pisarek

    2009-07-01

    Full Text Available The results of the investigations of the process of solidification of the bronze CuSn5Zn5Pb5-C (B555 and CuSn10-C (B10 in the hot plaster mould show in the work. For four temperatures of casting: 1200 ° C, 1180 ° C, 1160 ° C and 1140 ° C was conducted the investi-gation: the size of contraction cavity, the fulfillment of the mould cavity formative the casts of test slats about the thickness: 4 mm, 0,8 mm and 0,5 mm. It was conducted the investigation the processes sets in the arrangement the cast-mould and X-ray analysis phase XRD of compound coming into being in indirect layer created among mould and cast in the result of the thermal decomposition of the anhy-drite. It results that the temperature 1140 ° C is the optimum temperature of casting the bronze to hot plaster mould from carried out investiga-tions. The minimum thickness of the wall of the cast from the bronze B555 is 0.5 mm, and from the bronze B10 0.8 mm.The realization of casts about thinner walls is made difficult because of giving off formed gases in the result of the thermal decomposition of the anhydrite. The products of the decomposition of the anhydrite react with elements steps in the chemical composition of studied bronzes, create in the arrangement the cast-mould the indirect layer folded from: sulphites, sulphides, oxides and clean metals (Pb or their compounds, especially Sn and Sb.

  6. Chemical bath deposition and characterization of electrochromic thin films of sodium vanadium bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Najdoski, Metodija, E-mail: metonajd@yahoo.com [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of); Koleva, Violeta [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Demiri, Sani [Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius University, POB 162, Arhimedova 5, 1000 Skopje, Republic of Macedonia (Macedonia, The Former Yugoslav Republic of)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer We report a new chemical bath method for the deposition of vanadium bronze thin films. Black-Right-Pointing-Pointer The films are phase mixture of NaV{sub 6}O{sub 15} and Na{sub 1.1}V{sub 3}O{sub 7.9} with 10.58% lattice water. Black-Right-Pointing-Pointer The as-deposited vanadium bronze films exhibit two-step electrochromism. Black-Right-Pointing-Pointer They change their yellow-orange color to green and then from green to blue color. Black-Right-Pointing-Pointer The method allows the preparation of films on substrates with low melting point. -- Abstract: Thin yellow-orange films of sodium vanadium oxide bronzes have been prepared from a sodium-vanadium solution (1:1) at 75 Degree-Sign C and pH = 3. The composition, structure and morphology of the films have been studied by XRD, IR spectroscopy, TG and SEM-EDX analyses. It has been established that the prepared films are a phase mixture of hydrated NaV{sub 6}O{sub 15} (predominant component) and Na{sub 1.1}V{sub 3}O{sub 7.9} with total water content of 10.58%. The sodium vanadium bronze thin films exhibit two-step electrochromism followed by color change from yellow-orange to green, and then from green to blue. The cyclic voltammetry measurements on the as-deposited and annealed vanadium bronze films reveal the existence of different oxidation/reduction vanadium sites which make these films suitable for electrochromic devices. The annealing of the films at 400 Degree-Sign C changes the composition, optical and electrochemical properties.

  7. Chemical bath deposition and characterization of electrochromic thin films of sodium vanadium bronzes

    International Nuclear Information System (INIS)

    Highlights: ► We report a new chemical bath method for the deposition of vanadium bronze thin films. ► The films are phase mixture of NaV6O15 and Na1.1V3O7.9 with 10.58% lattice water. ► The as-deposited vanadium bronze films exhibit two-step electrochromism. ► They change their yellow-orange color to green and then from green to blue color. ► The method allows the preparation of films on substrates with low melting point. -- Abstract: Thin yellow-orange films of sodium vanadium oxide bronzes have been prepared from a sodium–vanadium solution (1:1) at 75 °C and pH = 3. The composition, structure and morphology of the films have been studied by XRD, IR spectroscopy, TG and SEM–EDX analyses. It has been established that the prepared films are a phase mixture of hydrated NaV6O15 (predominant component) and Na1.1V3O7.9 with total water content of 10.58%. The sodium vanadium bronze thin films exhibit two-step electrochromism followed by color change from yellow-orange to green, and then from green to blue. The cyclic voltammetry measurements on the as-deposited and annealed vanadium bronze films reveal the existence of different oxidation/reduction vanadium sites which make these films suitable for electrochromic devices. The annealing of the films at 400 °C changes the composition, optical and electrochemical properties

  8. Abertura floral de Dendranthema grandiflora Tzvelev. ´Bronze Repin´após rmazenamento a frio seguido de ?pulsing?

    Directory of Open Access Journals (Sweden)

    Bellé Rogério Antônio

    2004-01-01

    Full Text Available Visando estudar a abertura de inflorescências e a vida de vaso de crisântemo (Dendranthema grandiflora Tzvelev. ?Bronze Repin? colhido precocemente, montou-se um experimento em delineamento inteiramente casualizado bifatorial 2 x 6 com cinco repetições, realizado no Departamento de Fitotecnia da Universidade Federal de Santa Maria. As hastes foram armazenadas a 2ºC ou 5ºC por sete dias, sendo em seguida tratadas com soluções de ?pulsing? por 24h e mantidas em vasos com água de torneira, renovada a cada dois dias. As soluções utilizadas foram: Água (testemunha; Tiosulfato de Prata-STS 11mg.L-1 (Crysal AVB; Ácido Giberélico-GA3 50mg.L-1 (Pro-gibb; Hipoclorito de Sódio-NaOCl 200mg.L-1; 8-Hidroxiquinolina-8-HQ 100mg.L-1; Tiabendazole-TIBA 100mg.L-1(Tecto 100. Com exceção da testemunha, as outras soluções continham 2% de Sacarose. Com estes tratamentos, observou-se que não foi possível uma abertura perfeita da inflorescência, mas a vantagem foi de prolongar a sua vida, podendo-se colocá-las no mercado num momento mais oportuno.

  9. Habitabilidad de la vivienda de interés social prioritaria en el marco de la cultura. Reasentamiento de comunidades negras de Vallejuelos a Mirador de Calasanz en Medellín, Colombia. Habitability of the priority-affordable housing within the framework of culture. Resettlement of black communities from Vallejuelos to Mirador de Calasanz in Medellin, Colombia. Habitabilidade na habitação social prioritário no quadro da cultura. Reassentamento de comunidades pretas de Vallejuelos em Mirador de Calasanz em Medellín, Colômbia.

    Directory of Open Access Journals (Sweden)

    Elvia Marina Mena Romaña

    2011-07-01

    solutions built by the municipal administration in the context of public housing policy in Medellin. Methodologically, Mirador de Calazans was taken as a case study that characterizes the vast majority of the projects developed since 2001 to date, especially those built in the Pajarito Macroproject (northwest of Medellin. The method is qualitative and part of an ethnographic approach, which was conducted from life stories and general comments. The interest of this article explains the pervasiveness of this type of construction, lack of social responsibility when running housing, restrictive living conditions in the population and loss of identity that is generated in the different social groups. A moradia é habitada por diferentes pessoas e culturas que elas próprias implantam, pois a cultura é parte das suas vidas, fornecem identidade para os moradores e mesmo são transmitidas às moradias. Portanto, o modelo estandardizado implementado nas moradias chamadas de interesse prioritário (VIP, especificamente aquele desenhado para reassentamento de população, é uma limitante física que choca nos padrões culturais da população e gera conflitos associados à convivência. Neste artigo, indaga-se pela complexidade de morar em soluções habitacionais construídas pela administração municipal no marco da política pública de habitação de Medellín. Metodologicamente, o caso de estudo foi o Mirador de Calasanz, por caracterizar a maior parte dos projetos desenvolvidos desde 2001 até hoje, especialmente aqueles construídos no Macroprojeto de Pajarito (zona noroeste de Medellín. O método for qualitativo e parte duma perspectiva etnográfica, no qual foram realizadas entrevistas abertas, historias de vida e observação geral. O interesse deste artigo é explicado na propagação massiva deste tipo de edificações, falta de responsabilidade social na hora de construir moradias, condições restritivas em que as pessoas moram e a perda de identidade gerada nas

  10. Preliminary Study of Corrosion Status on Bronzes Excavated from Qin Dynasty Tombs at Xinfeng Town in China

    Directory of Open Access Journals (Sweden)

    Qian-li Fu

    2012-01-01

    Full Text Available From 2007 to 2008, many bronze wares of Qin Dynasty were excavated from tombs at Xinfeng town. Being an important finding, these bronze wares attracted people’s attention, especially for their conservation. Therefore, the corrosive products were explored by using Scanning Electron Microscope with Energy Dispersive X-ray Detector (SEM/EDS, X-Ray diffraction (XRD, and Raman spectroscopy (RM, which provided much valuable information on the conservation of these bronze wares. According to tested results, the corrosive products of bronzes were found to be comprised of cuprite (Cu2O, covellite (CuS, lead carbonate (PbCO3, and malachite (CuCO3·Cu(OH2. Meantime, the multilayer corrosive structure was found in some samples due to the cracks in Cu2O layer which had formed many microchannels to promote the material migration.

  11. Grain refinement of bronze alloy by equal-channel angular pressing (ECAP) and its effect on corrosion behaviour

    OpenAIRE

    M.M. Sadawy; Ghanem, M

    2016-01-01

    The corrosion behaviour of bronze alloy prepared by equal channel angular pressing (ECAP) was investigated in 3.5 wt. % NaCl solution. Immersion corrosion tests and different electrochemical techniques were carried out. The results showed that ECAPed bronze samples exhibited higher corrosion resistance compared with the as-cast alloy and the passive current density decreased with increasing number of passes. Moreover, the morphology of alloys indicated that the corrosion damage on the surface...

  12. Characterisation of passive layers of bronze patinas (Cu-Sn alloys) in relation with the tin content of the alloy

    OpenAIRE

    Robbiola, Luc; Fiaud, C.; Harch, A.

    1993-01-01

    International audience In order to develop our knowledge of the relations between the high degree of protectiveness of passive layers and their composition, corroded archaeological bronzes of Bronze Age (1500-950 BC) have been characterised by different methods of analysis. Results reveal that the passive layers have a bilayer structure and are due to the selective dissolution of copper from the copper solid solution of the alloy to the electrolyte. For all of the objects, the ratio [(Sn/C...

  13. Degradation measurement of bronzes, a recent application of the TLA techniques in the field of cultural heritage

    International Nuclear Information System (INIS)

    The thin layer technique is normally applied in wear and corrosion monitoring of mechanical and plant components. A recent applications refers to the field of Cultural Heritage. In particular thought national and international research programmes TLA is used as a sensitivity toll in determining the properties towards corrosion of new bronze alloys to be used for artistic purposes, as in manufacturing of outdoor artworks. One activated and exposed to natural or artificial corrosive environments the bronze surface is treated with pick ling solutions to remove the corrosion products, The corresponding thickness loss is determined by the relevant γ-activity loss. The method sensitivity allows of the thickness loss evaluation in the order micrometers of lower. Besides comparative analyses of the behaviour of different bronze alloys, this method is also applied in determining the effectiveness of corrosion inhibitor or protective films, normally used on outdoor bronze sculptures. The metal activation is carried out by using a cyclotron accelerated proton beam (11.5 MeV) which products on the bronze surface and along a defined depth γemitting radionuclide 65Zn (t1/2= 244 days). In the present paper, bronze corrosion results obtained in different environmental conditions as outdoor exposures and artificial weathering experiments are reported

  14. Characterisation of Late Bronze Age large size shield nails by EDXRF, micro-EDXRF and X-ray digital radiography

    International Nuclear Information System (INIS)

    In the present study six exceptional large size metallic nails, a dagger and a sickle from the Late Bronze Age archaeological site of Figueiredo das Donas (Central Portugal) have been analysed by EDXRF, micro-EDXRF and X-ray digital radiography for the study of material composition and technology of fabrication. The combination of these analytical and examination techniques showed that all artefacts are made of bronze with As, Sb and Pb impurities, and that the nails were most likely manufactured using the casting-on technique. These results reinforce the use of binary bronze by Late Bronze Age in the region, and the incorporation of new fabrication technologies that resulted from ancient spheres of interaction. - Highlights: → EDXRF, micro-EDXRF and X-ray digital radiography in cultural heritage studies. → Archaeometallurgical study of a Late Bronze Age artefact collection from Portugal. → Practise of a specific and traditional bronze metallurgy. → Appearance of technological innovations as the casting-on technique.

  15. Marco Calamari, Lampi di Cassandra: l’altro Steve

    OpenAIRE

    Pievatolo, Maria Chiara

    2011-01-01

    Mentre a Wozniak si devono i pochissimi momenti di apertura del software e del firmware Apple, "Jobs si è anche coperto del “fango” di aver scientemente concepito solo prodotti chiusi e di averli protetti con ogni arma fisica e legale possibile ed immaginabile, contribuendo non poco all’attuale pietoso e grave stato dell’informatica di consumo, e quindi della Rete stessa". Chi si avvicina all’informatica da utente potrebbe considerare tutto questo di interesse soltanto tecnico. Ma noi stu...

  16. Wet and dry accelerated aging tests in a spray chamber to understand the effects of acid rain frequencies on bronze corrosion

    OpenAIRE

    Gianni, Liliana; Cavallini, Mauro; Natali, Stefano; Adriaens, Annemie

    2013-01-01

    We have conducted controlled laboratory experiments using a series of bronze alloys exposed to frequent, repeated wet and dry cycles, to simulate frequent acid rain exposure and study the resultant corrosion processes in bronze artifacts exposed to an outdoor urban environment. To simulate rainwater and condensation, a spray chamber for the corrosion tests was assembled, which delivered homogeneous vapor diffusion and drop deposition. Three bi-component bronzes, with 3%, 7% and 20% tin conten...

  17. Marco de medición del grado de participación ciudadana en sitios web gubernamentales

    OpenAIRE

    Rodríguez, Rocío Andrea; Welicki, León Ezequiel; Estévez, Elsa Clara; Giulianelli, Daniel Alberto; Vera, Pablo Martín; Trigueros, Artemisa

    2010-01-01

    El objetivo de este artículo es presentar un marco de medición del grado de participación ciudadana en sitios web gubernamentales Este marco tiene como elemento central un conjunto de métricas las cuales pueden ser analizadas en cada uno de los sitios web de estudio. Al aplicar el marco de medición es posible analizar las métricas que son incumplidas lo cual dejará a la luz las deficiencias del sitio. Dado que las métricas de estudio tienen asignado un puntaje (ponderación) el marco de medici...

  18. El enfoque histórico cultural como marco conceptual para la investigación educativa

    OpenAIRE

    Wanda C. Rodríguez Arocho

    2010-01-01

    En este trabajo abogamos a favor del enfoque históricocultural como marco conceptual para la investigación educativa. En el desarrollo del tema discutimos qué es un marco conceptual y cuál es su rol en la investigación. Luego, analizamos el proceso que llevó a la configuración del enfoque históricocultural como marco conceptual para la investigación en psicología y educación y presentamos una síntesis del mismo. Argumentamos que este marco ofrece herramientas conceptuales y metodológicas para...

  19. Chronology for the Aegean Late Bronze Age 1700-1400 B.C.

    Science.gov (United States)

    Manning, Sturt W; Ramsey, Christopher Bronk; Kutschera, Walter; Higham, Thomas; Kromer, Bernd; Steier, Peter; Wild, Eva M

    2006-04-28

    Radiocarbon (carbon-14) data from the Aegean Bronze Age 1700-1400 B.C. show that the Santorini (Thera) eruption must have occurred in the late 17th century B.C. By using carbon-14 dates from the surrounding region, cultural phases, and Bayesian statistical analysis, we established a chronology for the initial Aegean Late Bronze Age cultural phases (Late Minoan IA, IB, and II). This chronology contrasts with conventional archaeological dates and cultural synthesis: stretching out the Late Minoan IA, IB, and II phases by approximately 100 years and requiring reassessment of standard interpretations of associations between the Egyptian and Near Eastern historical dates and phases and those in the Aegean and Cyprus in the mid-second millennium B.C. PMID:16645092

  20. The influence of modification by superdispersed powders on the lead-tin-base bronze structure

    Science.gov (United States)

    Semenkov, I. V.; Martyushev, N. V.; Popelyukh, A. I.; Alpeisov, A. T.; Drozdov, Yu Yu; Zykova, A. P.

    2016-04-01

    The paper presents data on the influence of additives of the pre-treated aluminium oxide powder on the structure of cast lead-tin-based bronzes. Different quantities of the modifier, based on the superdispersed aluminum oxide powder, were added to the bronze melt. The studies have shown that addition of a small amount of aluminum oxide powder (0.07... 0.25 %) allows modifying the micro structure of the obtained castings. This modification includes grain refinement, reduction of the matrix dendrites size of tin solid solution in copper, as well as formation of spherical inclusions of the low-melting phase - lead. In this case, the addition of such modifier influences weakly the morphology and the quantity of solid eutectoid inclusions based on electron compound Cu31 Sn8.

  1. Comparative modeling of Bronze Age land use in the Malatya Plain (Turkey)

    Science.gov (United States)

    Arıkan, Bülent; Restelli, Francesca Balossi; Masi, Alessia

    2016-03-01

    Computational modeling in archeology has proven to be a useful tool in quantifying changes in the paleoenvironment. This especially useful method combines data from diverse disciplines to answer questions focusing on the complex and non-linear aspects of human-environment interactions. The research presented here uses various proxy records to compare the changes in climate during the Bronze Age in the Malatya Plain in eastern Anatolia, which is situated at the northern extremity of northern Mesopotamia. Extensive agropastoral land use modeling was applied to three sites of different size and function in the Malatya Plain during the Early Bronze Age I period to simulate the varying scale and intensity of human impacts in relation to changes in the level of social organization, demography, and temporal length. The results suggest that even in land use types subjected to a light footprint, the scale and intensity of anthropogenic impacts change significantly in relation to the level of social organization.

  2. Multielement analysis of archaic Chinese bronze and antique coins by fast neutron activation analysis

    International Nuclear Information System (INIS)

    Samples of archaic bronze have been investigated by fast neutron activation analysis using both the absolute and relative method. The components Cu, Zn, Sn and Pb have been determined quantitatively. For the detection of lead via the short-lived isomeric state 207mPb, cyclic activation and measurement technique was used with pneumatic sample transfer between detector and central irradiation position of the neutron tube. For non-destructive analysis of antique Chinese coins the samples had to be irradiated outside the neutron generator KORONA. The activation reactions, the evaluation of the elemental concentrations and the accuracy of the results are discussed. The data were corrected for γ-ray self-absorption in the samples and summing of coincident γ-rays in the detector. According to reported typical compositions of Chinese bronze from different dynasties, the age of the samples has been derived from the results obtained. (orig.)

  3. Multielement analysis of archaic Chinese bronze and antique coins by fast neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Y.H. (Academia Sinica, Lanzhou, Gansu (China). Inst. of Modern Physics); Pepelnik, R.; Fanger, H.U. (GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht-Tesperhude (Germany, F.R.). Inst. fuer Physik)

    1990-01-01

    Samples of archaic bronze have been investigated by fast neutron activation analysis using both the absolute and relative method. The components Cu, Zn, Sn and Pb have been determined quantitatively. For the detection of lead via the short-lived isomeric state {sup 207m}Pb, cyclic activation and measurement technique was used with pneumatic sample transfer between detector and central irradiation position of the neutron tube. For non-destructive analysis of antique Chinese coins the samples had to be irradiated outside the neutron generator KORONA. The activation reactions, the evaluation of the elemental concentrations and the accuracy of the results are discussed. The data were corrected for {gamma}-ray self-absorption in the samples and summing of coincident {gamma}-rays in the detector. According to reported typical compositions of Chinese bronze from different dynasties, the age of the samples has been derived from the results obtained. (orig.).

  4. Connections: the relationships between Neolithic and Bronze Age Megalithic Astronomy in Britain

    CERN Document Server

    Higginbottom, Gail

    2015-01-01

    It has already been empirically verified that for many Bronze Age monuments erected in Scotland between 1400-900 BC, there was a concerted effort on behalf of the builders to align their monuments to astronomical bodies on the horizon. It has also been found that there are two common sets of complex landscape and astronomical patternings, combining specific horizon qualities, like distance and elevation, with the rising and setting points of particular astronomical phenomena. However, it has only been very recently demonstrated by us that that the visible astronomical-landscape variables found at Bronze Age sites on the inner isles and mainland of western Scotland were first established nearly two millennia earlier, with the erection of the mooted first standing-stone 'great circles' in Britain: Callanish and Stenness of Scotland (see G. Higginbottom and R. Clay, The Origins of Standing Stone Astronomy in Britain submitted to Journal of Archaeological Science & available on ArXiv). In the current paper we...

  5. Studies on bronze pre-monetary signs found in Dobroudja using XRF and micro-PIXE

    Science.gov (United States)

    Constantinescu, B.; Cristea-Stan, D.; Talmatchi, G.; Ceccato, D.

    2016-03-01

    We performed compositional analyses on 180 Scythian-type arrowheads and pre-monetary signs using XRF method and on 60 small fragments of such items (approx. 100 microns diameter), sampling being performed on previously corrosion-cleaned areas on their surface, using micro-PIXE. The items are found in Dobroudja, Istros-Histria region. The most relevant for numismatists result is that for each finding place the same type of alloy was used both for fighting arrowheads and for pre-monetary signs. Our analyses revealed three types of alloys: Cu-Sn-Pb ("normal" bronze), Cu-Sn-Mn-Pb and Cu-Sn-Sb-Pb. The presence of antimony suggests the use of fahlore-type poly-metals deposits, most probably from Caucasus Mountains. The problem of ancient bronze containing manganese is more complicated; an explanation could be the use of manganese oxides as flux necessary to smelt oxidized ores.

  6. Palaeodemographic and palaeopathological characteristics of individuals buried in three Bronze Age sites from southern Croatia

    Directory of Open Access Journals (Sweden)

    M. Novak

    2011-12-01

    Full Text Available The purpose of this study is to reconstruct paleodemographic and paleopathological characteristics of sixteen individuals (three subadults, seven males and six females buried in three Bronze Age sites (Crip, Matkovići, and Veliki Vanik located in southern Croatia. The analysed sample is characterised by the presence of pathological changes which are often associated with stressful episodes such as anaemia, inadequate nutrition, infectious diseases and the occurrence of parasites. Cribra orbitalia, dental enamel hypoplasia, porotic hyperostosis and periostitis were observed in seven out of sixteen analysed skeletons. One ulnar “parry” fracture and three fractures of the frontal bone strongly suggest the presence of deliberate interpersonal violence within the studied communities. The average life span of the adults, as well as the number and character of the observed pathologies, suggest a relatively poor life quality and harsh living conditions in the studied region during the Bronze Age.

  7. Marks of heliacal rising of Sirius on the sundial of the Bronze Age

    CERN Document Server

    Vodolazhskaya, Larisa N; Nevsky, Mikhail Yu

    2015-01-01

    The article presents the results of interdisciplinary research made with the help of archaeological, physical and astronomical methods. The aim of the study were analysis and interpretation corolla marks of the vessel of the Late Bronze Age, belonging to Srubna culture and which was found near the Staropetrovsky village in the northeast of the Donetsk region (Central Donbass). Performed calculations and measurements revealed that the marks on the corolla of Staropetrovsky vessel are marking of horizontal sundial with a sloping gnomon. Several marks on the corolla of the vessel have star shape. Astronomical calculations show that their position on the corolla, as on "dial" of watch, indicates the time of qualitative change the visibility of Sirius in the day its heliacal rising and the next few days in the Late Bronze Age at the latitude of detection of Staropetrovsky vessel. Published in the article the results of astronomical calculations allow to state that astronomical year in the Srubna tradition began wi...

  8. Radiocarbon dating of ancient bronze statues: Preliminary results from the Riace statues

    International Nuclear Information System (INIS)

    The low amount of material needed for the measurements makes AMS radiocarbon a technique suitable for the dating of ancient bronze artefacts through the analysis of the organic residues contained into the casting cores. We present the results of the AMS radiocarbon dating analyses carried out on the organic remains extracted from the casting cores of the Riace bronzes, among the most famous and well preserved sculptures of the Greek-Classical period. Although different dating hypotheses have been suggested on the base of stylistic considerations, no conclusive answers are, so far, available. The sample selection and preparation protocols of the different kind of organic materials (charred wood, vegetal remains and animal hairs) are described as well as the interpretation of the results in the frame of the current dating hypotheses and available analytical information about the casting technology.

  9. Biological affinities and adaptations of Bronze Age Bactrians: III. An initial craniometric assessment.

    Science.gov (United States)

    Hemphill, B E

    1998-07-01

    Discovery of a previously unknown Bronze Age civilization (Oxus Civilization) centered on the oases of Central Asia immediately raised questions concerning the origin and interregional impacts of this civilization. Fifteen craniometric variables from 12 Bronze Age samples--encompassing 544 adults from Central Asia, Iran, the Indus Valley, and Anatolia--are compared to test which, if any, of the current hypotheses offered by archaeologists are best supported by the pattern of phenetic affinities possessed by the Oxus Civilization inhabitants of the north Bactrian oasis. Craniometric differences between samples are compared with Mahalanobis generalized distance, and patterns of phenetic affinity are assessed with two types of cluster analysis (WPGMA, neighbor-joining method), multidimensional scaling, and principal coordinates analysis. Results obtained by this analysis indicate that current hypotheses for both the origin and interregional impacts of Oxus Civilization populations are incomplete. PMID:9696149

  10. Observações sôbre o bronzeado do algodoeiro Mocó Observations on bronzing of the Mocó cotton

    Directory of Open Access Journals (Sweden)

    A. S. Costa

    1955-01-01

    Full Text Available Uma anomalia do algodoeiro Mocó, denominada bronzeado, vem sendo observada na região do Seridó, Rio Grande do Norte, durante os últimos três anos. Pensou-se, a princípio, que esta anomalia fôsse causada por um vírus, mas as observações relatadas neste trabalho indicam que é causada por um ácaro. As fôlhas das plantas afetadas, especialmente aquelas da metade superior dos galhos, mostram uma coloração bronzeada no lado de baixo. Essa face da fôlha tem também uma superfície rugosa, com brilho vidrado (est. 1, B, as vezes com pequenas áreas de tecido cicatricial. Vistas pelo lado de cima são mais rugosas do que as normais e têm os bordos curvados para baixo. Nos casos graves, as fôlhas do topo dos galhos morrem e caem (est. 2, A e B. A espécie de ácaro causadora do bronzeado do algodoeiro Mocó foi identificada por H. H. Keifer, Sacramento, Calif., como pertencente a um gênero ainda não descrito da família Eriophyidae. Esta espécie está sendo presentemente denominada Anthocoptes sp. até que a sua descrição seja publicada. Populações de 500 a 1.000 indivíduos por centímetro quadrado de fôlha já foram encontradas. Esse ácaro parece ser muito sensível às condições do ambiente, visto que as populações da praga variam entre grandes limites.For the last three years a bronzing anomaly of cotton plants of the Mocó variety (Gossypium hirsutum L. var. maria galante Hutch. has been recorded in the Seridó region (a semi-arid region in the north-eastern part of Brazil, state of Rio Grande do Norte. This anomaly was first thought to be of virus origin, but the observations reported in this paper indicated that it is due to the attack by a species of mite. Leaves from affected plants, especially those on the upper half of the branches, show a bronzing discoloration on the dorsal side, frequently accompanied by a rough and ventral side of these leaves shows some rugosity not present in normal leaves, and in most cases

  11. Textile remains on a Roman bronze vessel from Řepov (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Urbanová, K.; Březinová, Helena

    Vol. 10. Oxford : Oxbow Books, 2010 - (Andersson Strand, E.; Gleba, M.; Mannering, U.; Munkholt, C.; Ringgaard, M.), s. 242-246 ISBN 978-1-84217-370-1. - (Ancient Textile s. 5). [North European Symposium for Archaeological Textile s /10./. Copenhagen (DK), 14.05.2008-17.05.2008] Institutional research plan: CEZ:AV0Z80020508 Keywords : textile remains * corrosion products * Roman bronze vessel Subject RIV: AC - Archeology, Anthropology, Ethnology

  12. Neolithic and Bronze Age migration to Ireland and establishment of the insular Atlantic genome.

    Science.gov (United States)

    Cassidy, Lara M; Martiniano, Rui; Murphy, Eileen M; Teasdale, Matthew D; Mallory, James; Hartwell, Barrie; Bradley, Daniel G

    2016-01-12

    The Neolithic and Bronze Age transitions were profound cultural shifts catalyzed in parts of Europe by migrations, first of early farmers from the Near East and then Bronze Age herders from the Pontic Steppe. However, a decades-long, unresolved controversy is whether population change or cultural adoption occurred at the Atlantic edge, within the British Isles. We address this issue by using the first whole genome data from prehistoric Irish individuals. A Neolithic woman (3343-3020 cal BC) from a megalithic burial (10.3× coverage) possessed a genome of predominantly Near Eastern origin. She had some hunter-gatherer ancestry but belonged to a population of large effective size, suggesting a substantial influx of early farmers to the island. Three Bronze Age individuals from Rathlin Island (2026-1534 cal BC), including one high coverage (10.5×) genome, showed substantial Steppe genetic heritage indicating that the European population upheavals of the third millennium manifested all of the way from southern Siberia to the western ocean. This turnover invites the possibility of accompanying introduction of Indo-European, perhaps early Celtic, language. Irish Bronze Age haplotypic similarity is strongest within modern Irish, Scottish, and Welsh populations, and several important genetic variants that today show maximal or very high frequencies in Ireland appear at this horizon. These include those coding for lactase persistence, blue eye color, Y chromosome R1b haplotypes, and the hemochromatosis C282Y allele; to our knowledge, the first detection of a known Mendelian disease variant in prehistory. These findings together suggest the establishment of central attributes of the Irish genome 4,000 y ago. PMID:26712024

  13. Friction stir processing and fusion welding in nickel aluminum propeller bronze

    OpenAIRE

    Fuller, Michael D.

    2006-01-01

    Friction Stir Processing (FSP) is currently being developed for applications including as-cast Nickel- Aluminum Bronze (NAB). Fabrication and repair of the United States Navy's NAB propellers involve fusion welding of as-cast NAB and so it is probable that FSP is likely to encounter as deposited weld metal as well as the more slowly cooled as-cast material. Here, the microstructure and resulting distribution of mechanical properties was examined for a fusion weld overlay, an FSP stir zone an...

  14. An attempt to date an antique Benin bronze using neutron resonance capture analysis

    Energy Technology Data Exchange (ETDEWEB)

    Blaauw, M. [Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)]. E-mail: blaauw@iri.tudelft.nl; Postma, H. [Interfaculty Reactor Institute, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands); Mutti, P. [IRMM, Joint Research Centre, Retieseweg, 2440 Geel (Belgium)

    2005-03-01

    Neutron resonance capture analysis was applied to a bronze commemorative plaque from the West-African country Benin. By comparison with recently published element compositions of Benin memorial heads, the alloy of the plaque could be dated to the period 1725-1897 AD. In the analysis procedure, the object was not damaged, cleaned or altered, and very little long-lived radioactivity was induced.

  15. An attempt to date an antique Benin bronze using neutron resonance capture analysis

    International Nuclear Information System (INIS)

    Neutron resonance capture analysis was applied to a bronze commemorative plaque from the West-African country Benin. By comparison with recently published element compositions of Benin memorial heads, the alloy of the plaque could be dated to the period 1725-1897 AD. In the analysis procedure, the object was not damaged, cleaned or altered, and very little long-lived radioactivity was induced

  16. An attempt to date an antique Benin bronze using neutron resonance capture analysis.

    Science.gov (United States)

    Blaauw, M; Postma, H; Mutti, P

    2005-03-01

    Neutron resonance capture analysis was applied to a bronze commemorative plaque from the West-African country Benin. By comparison with recently published element compositions of Benin memorial heads, the alloy of the plaque could be dated to the period 1725-1897 AD. In the analysis procedure, the object was not damaged, cleaned or altered, and very little long-lived radioactivity was induced. PMID:15607919

  17. Some spatial aspects of the ritual behaviour at the beginning of Bronze Age

    Czech Academy of Sciences Publication Activity Database

    Kruťová, Magdalena; Turek, J.

    Plzeň : Čeněk, 2004 - (Šmejda, L.; Turek, J.), s. 48-56 ISBN 80-86898-07-5. [Annual Meeting of the European Association of Archaeologists /8./. Thessaloniki (GR), 24.09.2002-29.09.2002] Institutional research plan: CEZ:AV0Z8002910 Keywords : continuity * spatial relationships * cemmeteries * Bronze Age Subject RIV: AC - Archeology, Anthropology, Ethnology

  18. Altered states of consciousness and ritual in late Bronze Age Cyprus

    OpenAIRE

    Collard, David

    2011-01-01

    This thesis combines an anthropological approach to the study of Altered States of Consciousness (ASCs) with a detailed analysis of previously published evidence for the consumption of psychoactives from Late Bronze Age Cypriote (Late Cypriote) contexts to investigate the possibility that such mental phenomena may have been utilised within religious rituals of this period. This evidence primarily consists of ceramic vessels associated with the consumption of opium and alcohol (often supported...

  19. Screen-printed platinum electrodes for measuring crevice corrosion: Nickel aluminium bronze as an example

    OpenAIRE

    Cranny, Andrew; Harris, Nick; Lewis, Adam; Nie, Menyang; Wharton, Julian; Wood, Robert; Stokes, Keith

    2010-01-01

    Screen-printed platinum electrodes were used to monitor crevice corrosion processes. The electrodes, printed on an inert alumina substrate, formed the bottom of an artificial crevice when mechanically clamped to a rectangular block of nickel-aluminium bronze (NAB). Cyclic differential pulse voltammetry was used to detect corrosion products over time whilst the assembly was immersed in a 3.5% by weight aqueous solution of sodium chloride. Cupric (Cu2+), ferric (Fe3+) and ferrous (Fe2+) ions we...

  20. Electrochemical monitoring of nickel–aluminium bronze crevice corrosion solutions using boron–doped diamond electrode

    OpenAIRE

    Neodo, Stefano

    2013-01-01

    This study has demonstrated the capability of electrochemically assessing the metal–ion concentrations generated from the localised corrosion of nickel–aluminium bronzes (NAB). Prior to investigating NAB crevice corrosion, its electrochemical properties were studied at different pHs and chloride concentrations. At solution pHs higher than 4 NAB exhibited a corrosion behaviour similar to that of unalloyed copper and its oxidation was controlled by the dissolution of the copper–rich ?–phase. Ho...

  1. Palaeodemographic and palaeopathological characteristics of individuals buried in three Bronze Age sites from southern Croatia

    OpenAIRE

    Novak, M; V. Vyroubal; Ž. Bedić

    2011-01-01

    The purpose of this study is to reconstruct paleodemographic and paleopathological characteristics of sixteen individuals (three subadults, seven males and six females) buried in three Bronze Age sites (Crip, Matkovići, and Veliki Vanik) located in southern Croatia. The analysed sample is characterised by the presence of pathological changes which are often associated with stressful episodes such as anaemia, inadequate nutrition, infectious diseases and the occurrence of parasites. Cribra or...

  2. New insight into the nature and properties of pale green surfaces of outdoor bronze monuments

    Science.gov (United States)

    Robbiola, L.; Rahmouni, K.; Chiavari, C.; Martini, C.; Prandstraller, D.; Texier, A.; Takenouti, H.; Vermaut, P.

    2008-07-01

    The present study concerns the chemical physical and electrochemical characterisations of the pale green surfaces formed on outdoor bronzes exposed in urban conditions. In the first part, results from investigations performed on the equestrian statue of the French king Louis XIV exposed in the Palace of Versailles (France) are given. Analyses by energy-dispersive spectrometry and Raman spectroscopy, coupled with scanning electron microscopy, show that the external layer is characterised by a marked selective dissolution of copper and zinc of the alloy leading to an important relative enrichment in tin compounds. The same phenomenon with the same magnitude, determined from dissolution factors fCu and fZn, has also been evidenced on other bronze monuments used for comparison. Proportionality between the amount of dissolved copper and zinc cations to their respective initial content in the alloy is evidenced independently of the tin content. The pale green patina appears to be a complex mixture of copper and tin compounds whose structure still needs to be more precisely characterised. In the second part, the electrochemical reactivity of tin compound enriched patina was investigated by cyclic voltammetry from a Cu10Sn electrode in sulfate solution at pH=2 and 5.6. This patina is stable at pH 5.6 but reactive at pH 2 in relation to the modification of properties of tin species in the patina. Mott Schottky application in pH 5.6 solution revealed that the bronze patina exhibits two types of semiconducting properties according to the potential domains, similar to what has been observed for pure tin in aqueous solutions. The destabilisation of bronze patinas in outdoor conditions and consequently the cyclic erosion due to rainfall have been attributed to the modification of tin species properties rather than to the transformation of copper compounds.

  3. On the Origin of Bronze Belt Plaques of Ancient Nomads in Northern China

    Institute of Scientific and Technical Information of China (English)

    WUEn; 丁小雷

    2003-01-01

    The bronze plaques decorated with animal, human or geometric designs were the ornaments on the leather belts of the nomadic people, such as Xiongnu (Hun) and Xianbei (Sienpi) in Northern China in the Qin and Han Dynasties. These plaques had unique regional and ethnical characteristics. There have been many different ideas on the origination of this kind of plaques. The author plans to give his own opinion hereby on this issue.

  4. Connections: the relationships between Neolithic and Bronze Age Megalithic Astronomy in Britain

    OpenAIRE

    Higginbottom, Gail; Clay, Roger

    2015-01-01

    It has already been empirically verified that for many Bronze Age monuments erected in Scotland between 1400-900 BC, there was a concerted effort on behalf of the builders to align their monuments to astronomical bodies on the horizon. It has also been found that there are two common sets of complex landscape and astronomical patternings, combining specific horizon qualities, like distance and elevation, with the rising and setting points of particular astronomical phenomena. However, it has ...

  5. Towards mineralogical and geochemical reference groups for some Bronze Age ceramics 
from Transylvania (Romania)

    OpenAIRE

    Volker Hoeck; Corina Ionescu; Lucretia Ghergari; Carmen Precup

    2009-01-01

    Based on their chemical composition ceramic shards from three Bronze Age sites in Transylvania, i.e., Copăceni, Derşida and Palatca respectively, were distinguished by major, trace, and RE elements. Within the Copăceni samples, two subgroups (A and B) showing different chemistry and mineralogy were additionally separated out. The link between chemistry and mineralogy showed clearly the important contribution of the temper to the overall chemistry of the ceramic shards. In turn, the chemistry ...

  6. 黑豆嘴类型青铜器中的西来因素%Western Elements in the Bronzes of Heidouzui Type

    Institute of Scientific and Technical Information of China (English)

    张文立; 林沄

    2004-01-01

    The cultural elements contained in the bronzes of Heidouzui type have often been studied in academic circles,but no unanimous views have been reached.The present paper discusses two forms of bronze ornaments of the Kayao culture in the Qinghai region and their date,as well as the relationship of some bronzes handed down from ancient times with those unearthed from Qinghai.On the basis of their comparative study the authors put forward that the Heidouzui-type bronzes contain cultural elements coming from the Qinghai region and even farther areas.These western elements might have been spread eastward and northward to still farther regions.

  7. The metal–insulator transition in trivalent-ion-doped tungsten bronzes

    International Nuclear Information System (INIS)

    Electrical transport measurements have been made on a series of trivalent-ion-doped tungsten bronzes MxWO3, with M = Y (0.05 ≤ x ≤ 0.12) or La (0.05 ≤ x ≤ 0.19), over the temperature range 2–300 K. The results are consistent with a metal–insulator transition (MIT) at a critical concentration xC ≃ 0.06, which corresponds to an electron concentration nC ≃ 3.3 × 1021 cm−3. The appearance of small concentrations of non-cubic phases for x ∼ xC does not have a significant impact on the evolution of the electronic properties of the trivalent bronzes in the low x range. Analysis of the transport results, and a comparison of the findings with those obtained by other workers for the sodium tungsten bronzes, suggest that electron–electron interaction effects play a significant role in inducing the MIT in this type of disordered system. (paper)

  8. Processing parameter optimization for the laser dressing of bronze-bonded diamond wheels

    Science.gov (United States)

    Deng, H.; Chen, G. Y.; Zhou, C.; Li, S. C.; Zhang, M. J.

    2014-01-01

    In this paper, a pulsed fiber-laser dressing method for bronze-bonded diamond wheels was studied systematically and comprehensively. The mechanisms for the laser dressing of bronze-bonded diamond wheels were theoretically analyzed, and the key processing parameters that determine the results of laser dressing, including the laser power density, pulse overlap ratio, ablation track line overlap ratio, and number of scanning cycles, were proposed for the first time. Further, the effects of these four key parameters on the oxidation-damaged layer of the material surface, the material removal efficiency, the material surface roughness, and the average protrusion height of the diamond grains were explored and summarized through pulsed laser ablation experiments. Under the current experimental conditions, the ideal values of the laser power density, pulse overlap ratio, ablation track line overlap ratio, and number of scanning cycles were determined to be 4.2 × 107 W/cm2, 30%, 30%, and 16, respectively. Pulsed laser dressing experiments were conducted on bronze-bonded diamond wheels using the optimized processing parameters; next, both the normal and tangential grinding forces produced by the dressed grinding wheel were measured while grinding alumina ceramic materials. The results revealed that the normal and tangential grinding forces produced by the laser-dressed grinding wheel during grinding were smaller than those of grinding wheels dressed using the conventional mechanical method, indicating that the pulsed laser dressing technology provides irreplaceable advantages relative to the conventional mechanical dressing method.

  9. Evaluation of the inhibitive effect of benzotriazole on archeological bronze in acidic medium

    Science.gov (United States)

    Hassairi, Hèla; Bousselmi, Latifa; Khosrof, Slim; Triki, Ezzeddine

    2013-12-01

    An archaeological bronze artefact was a Punic coin excavated from the north east of Tunisia in 2001. The composition of the copper alloy revealed a content of 3.5 % of tin and 1.4 % of lead with the presence of some sulphur heterogeneity. The surface presents some roughnesses and cracks and is covered by a corrosion layer of 20-40 μm thickness. The use of benzotriazole (BTA) as an inhibitor has become a standard element for the preservation of cuprous-based metals. In order to investigate the behaviour of BTA in an acidic medium, an Electrochemical Impedance Spectroscopy (EIS) investigation was performed to characterize the electrochemical behaviour of the interface of the archaeological bronze sample/acidic medium without and with BTA addition. Impedance diagrams obtained at different immersion times show that the presence of the inhibitor prevents the diffusional process observed in the absence of BTA. The inhibition of the pre-polarized bronze surface revealed that the mechanism of action of the benzotriazole molecule in an acidic medium is governed by the chemisorption process.

  10. Effect of heat treatment on microstructure and properties of hot-extruded nickel-aluminum bronze

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effect of heat treatment on the microstructure and properties of a hot-extruded nickel-aluminum bronze was investigated. Experimental materials were heat treated through different processes, including quenching, normalizing, aging and annealing, and their microstructure, corrosion resistance and mechanical properties were characterized. It is found that quenching causes all β phase transformed into β' phase, however, normalizing causes β phase transformed into β', α and κ phases. When the quenched sample is aged, fine κ phase is precipitated from the as-quenched microstructure of β' phase. Annealing causes the transformation of β' into a and κ phases. The results of mechanical property tests show that quenching, normalizing and aging improve the tensile strength and hardness of the experimental material, with a corresponding fall in elongation. Annealing raises the elongation but reduces the tensile strength and hardness. Furthermore, corrosion resistance of nickel-aluminum bronze ranks from worse to better in the following order: aged, quenched, normalized, hot-extruded and annealed. However, with the exposure time of corrosion test increasing, the difference of average corrosion rate between those nickel-aluminum bronzes tums small.

  11. Properties and performance of fine-filament bronze-process Nb3Sn conductors

    Science.gov (United States)

    Walker, M. S.; Cutro, J. M.; Zeitlin, B. A.; Ozeryansky, G. M.; Schwall, R. E.; Oberly, C. E.; Ho, J. C.; Woollam, J. A.

    1979-01-01

    Fine-filament bronze-process Nb3Sn superconductors were fabricated to fulfill stringent requirements on critical current under tension in a one-inch bend diameter, current density, stability, and conductor losses. A large fraction of niobium filaments was incorporated in a bronze matrix, and a cable containing 4453 2-micron diameter filaments in each of six strands provided a current density of 85,000 A/sq cm at 10 to the -11th ohm-cm, 10 T, and 4.2 K. The next step was to incorporate copper stabilizer in a conductor with 20,538 filaments. These conductors, fabricated so that bend strains of about 1% would be experienced by the filaments in the one-inch bend, stably carried currents in the 200-500 A range. A quench current of 540 A in a 5-cm bend corresponds to 158,000 A/sq cm in the bronze and filament area, believed to be the highest critical current density reported for multifilamentary Nb3Sn.

  12. Band structure of the quasi two-dimensional purple molybdenum bronze

    Science.gov (United States)

    Guyot, H.; Balaska, H.; Perrier, P.; Marcus, J.

    2006-09-01

    The molybdenum purple bronze KMo 6O 17 is quasi two-dimensional (2D) metallic oxide that shows a Peierls transition towards a metallic charge density wave state. Since this specific transition is directly related to the electron properties of the normal state, we have investigated the electronic structure of this bronze at room temperature. The shape of the Mo K1s absorption edge reveals the presence of distorted MoO 6 octahedra in the crystallographic structure. Photoemission experiments evidence a large conduction band, with a bandwidth of 800 meV and confirm the metallic character of this bronze. A wide depleted zone separates the conduction band from the valence band that exhibits a fourfold structure, directly connected to the octahedral symmetry of the Mo sites. The band structure is determined by ARUPS in two main directions of the (0 0 1) Brillouin zone. It exhibits some unpredicted features but corroborates the earlier theoretical band structure and Fermi surface. It confirms the hidden one-dimensionality of KMo 6O 17 that has been proposed to explain the origin of the Peierls transition in this 2D compound.

  13. Density-functional studies of tungsten trioxide, tungsten bronzes, and related systems

    CERN Document Server

    Ingham, B; Chong, S V; Tallon, J L

    2005-01-01

    Tungsten trioxide adopts a variety of structures which can be intercalated with charged species to alter the electronic properties, thus forming `tungsten bronzes'. Similar optical effects are observed upon removing oxygen from WO_3, although the electronic properties are slightly different. Here we present a computational study of cubic and hexagonal alkali bronzes and examine the effects on cell size and band structure as the size of the intercalated ion is increased. With the exception of hydrogen (which is predicted to be unstable as an intercalate), the behaviour of the bronzes are relatively consistent. NaWO_3 is the most stable of the cubic systems, although in the hexagonal system the larger ions are more stable. The band structures are identical, with the intercalated atom donating its single electron to the tungsten 5d valence band. Next, this was extended to a study of fractional doping in the Na_xWO_3 system (0 < x < 1). A linear variation in cell parameter, and a systematic change in the po...

  14. Density-functional studies of tungsten trioxide, tungsten bronzes, and related systems

    Science.gov (United States)

    Ingham, B.; Hendy, S. C.; Chong, S. V.; Tallon, J. L.

    2005-08-01

    Tungsten trioxide adopts a variety of structures which can be intercalated with charged species to alter the electronic properties, thus forming “tungsten bronzes.” Similar effects are observed upon removing oxygen from WO3 . We present a computational study of cubic and hexagonal alkali bronzes and examine the effects on cell size and band structure as the size of the intercalated ion is increased. With the exception of hydrogen (which is predicted to be unstable as an intercalate), the behavior of the bronzes are relatively consistent. NaWO3 is the most stable of the cubic systems, although in the hexagonal system the larger ions are more stable. The band structures are identical, with the intercalated atom donating its single electron to the tungsten 5d valence band. A study of fractional doping in the NaxWO3 system (0⩽x⩽1) showed a linear variation in cell parameter and a systematic shift in the Fermi level into the conduction band. In the oxygen-deficient WO3-x system the Fermi level undergoes a sudden jump into the conduction band at around x=0.2 . Lastly, three compounds of a layered WO4•α,ω -diaminoalkane hybrid series were studied and found to be insulating, with features in the band structure similar to those of the parent WO3 compound that relate well to experimental UV-visible spectroscopy results.

  15. A systematic approach to Bronze corrosion products and the methods of treatment , applied on three bronze anklets from Dhamar museum , Yemen

    Directory of Open Access Journals (Sweden)

    Hazem Mohamed

    2014-04-01

    Full Text Available Three bronze anklets were found during the archaeological excavation of Yemeni mission 2002 A.D, in Gabal al- lawd , Jawf area , Yemen , they dated back to Minaean period in Yemen [sixth century B.C – 24 B.C] , and now they are situated in Dhamar regional museum .They were suffered from the deterioration aspects , two of these anklets had a thick corrosion products of pale green / brown , the third anklet had a rust-colored Black and Brown with the presence of small parts and scattered pale green. The aim of this paper is to examine, in detail, the corrosion of the selected objects that was grown during the long-term burial and identify its products that will help us to understand the corrosive factors and the degradation mechanisms , as well as their constituting metals in order to carry out scientific treatment and conservation .For this purpose ,samples from the objects were examined by Metallographic Microscope (ME , Scanning Electron Microscope (SEM, the corrosion products were analyzed by X-ray diffraction (XRD and X-ray fluorescence( XRF was used to determine the objects metallic constituents . XRD data showed that the corrosion products constitute of cuprite , atacamite , and paratacamite , whereas XRF analysis declared that the anklets compose of bronze alloy . Microscopic examination reveals that the three anklets were suffered from the deterioration spots , which dispersed on the metal surface . Chemical cleaning was chosen for treating the objects , finally they were isolated to preserve them against further attack.

  16. Identidad de los abogados y formación universitaria en un marco de crisis

    OpenAIRE

    Marcelo Héctor Efrón

    2009-01-01

    El presente trabajo, realizado en el marco del Seminario sobre Perspectivas Filosófico-Políticas de la Educación Contemporánea a cargo del Prof. Dr. Carlos Cullen, tiene como objetivo efectuar una breve una aproximación a la idea de identidad de los abogados, para posteriormente abordar algunos enfoques sobre el derecho y justicia, haciendo un rápido pasaje hacia una muy simplificada referencia a la formación de abogados en el marco de lo que entendemos como una crisis de identidad profesion...

  17. El circo criollo en el marco de la construcción de la nacionalidad argentina

    OpenAIRE

    Sánchez, Daniel; Andruchow, Marcela; Cordero, Silvina

    2005-01-01

    El presente trabajo tiene como objetivo analizar desde una perspectiva crítica e interpretativa y como producción simbólica al denominado Circo criollo, en el marco espacial de la Ciudad y la Provincia de Buenos Aires y temporal de la segunda mitad del siglo XIX., partiendo de la premisa de entender a dicha manifestación cultural, como un emergente importante para analizar el proceso histórico y social en un marco de urbanización y modernización acelerada de países con alta inmigración. El ci...

  18. VAGINAL ECONOMY: Cinema and Globalization in the Post-Marcos Post-Brocka Era

    Directory of Open Access Journals (Sweden)

    Rolando B. Tolentino

    2010-12-01

    Full Text Available This essay explores the trope of the vaginal economy that is proliferated in the political economy and nature of Philippine migration. The vaginal economy is both receptacle and symptom of Philippine development. It represents the discourse through cinema, and historicizes the primal debate in the Marcos and Brocka contestation for image-building of the nation. Primarily through the sex-oriented (bomba films and their permutations in the various political life of the contemporary nation, the vaginal economy is historicized even in the after-life of the post-Marcos and post-Brocka era.

  19. Ser gestante soropositivo para o Vírus da Imunodeficiência Humana: uma leitura à luz do Interacionismo Simbólico Ser gestante seropositiva para el Virus de la inmunodeficiencia humana-HIV: una lectura bajo el marco teórico del Interaccionismo Simbólico Being pregnant seropositive and having acquired the human immunodeficiency Virus (HIV): a theoretical interpretation under the Symbolic Interactionism

    OpenAIRE

    Edilene Lins de Moura; Amélia Fumiko Kimura; Neide de Souza Praça

    2010-01-01

    OBJETIVO: Descrever o contexto do cotidiano vivido por mulheres grávidas soropositivas para o Vírus da Imunodeficiência Humana (HIV), com enfoque na experiência de tornar-se grávida e assumir a gravidez. MÉTODOS: Os dados foram coletados por meio de entrevista gravada, com 14 gestantes sabidamente soropositivas para o HIV, que vivenciavam o terceiro trimestre de gravidez. O estudo fez uma leitura de dados brutos sobre expectativas e ações de gestantes soropositivas para o HIV, à luz do Intera...

  20. {sup 14}C dating of the Early to Late Bronze Age stratigraphic sequence of Aegina Kolonna, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Wild, E.M., E-mail: Eva.Maria.Wild@univie.ac.a [VERA Laboratory, Faculty of Physics - Isotope Research, University of Vienna, Waehringer Strasse 17, A-1090 Wien (Austria); Gauss, W. [Austrian Archaeological Institute at Athens, Leof. Alexandras 26, Gr10683 Athens (Greece); Forstenpointner, G. [University of Veterinary Medicine Vienna, Dept. of Pathobiology, Institute of Anatomy, Unit on Archaeozoology and Comparative Morphology, Veterinaerplatz 1, A-1210 Vienna (Austria); Lindblom, M. [Dept. of Archaeology and Ancient History Uppsala, University Box 626, SE-751 26 Uppsala (Sweden); Smetana, R. [Altertumswissenschaften, University of Salzburg, Residenzplatz 1/I, A-5020 Salzburg (Austria); Steier, P. [VERA Laboratory, Faculty of Physics - Isotope Research, University of Vienna, Waehringer Strasse 17, A-1090 Wien (Austria); Thanheiser, U. [Vienna Institute for Archaeological Science (VIAS), Althanstrasse 14, A-1090 Vienna (Austria); Weninger, F. [VERA Laboratory, Faculty of Physics - Isotope Research, University of Vienna, Waehringer Strasse 17, A-1090 Wien (Austria)

    2010-04-15

    Aegina Kolonna, located in the center of the Saronic Gulf in the Aegean Mediterranean (Greece), is one of the major archaeological sites of the Aegean Bronze Age with a continuous stratigraphic settlement sequence from the Late Neolithic to the Late Bronze Age. Due to its position next to the maritime cross roads between central mainland Greece, the northeast Peloponnese, the Cyclades and Crete, the island played an important role in the trade between these regions. In the course of new excavations, which focused on the exploration of the Early, Middle and Late Bronze Age at Kolonna, several short lived samples from different settlement phases have been {sup 14}C-dated with the AMS method at the VERA laboratory. Bayesian sequencing of the {sup 14}C data according to the stratigraphic position of the samples in the profile was performed to enable estimates of the transition time between the cultural phases. The Aegina Kolonna {sup 14}C sequence is one of the longest existing so far for the Aegean Bronze Age, and therefore of major importance for the absolute Bronze Age chronology in this region. Preliminary results indicate that the Middle Helladic period seems to have started earlier and lasted longer than traditionally assumed. Further, at the present stage of our investigation we can give also a very tentative time frame for the Santorini volcanic eruption which seems to be in agreement with the science derived VDL date.

  1. Lead isotopic study of Shang Dynasty bronzes (13-11 B.C.) and their ore sources

    International Nuclear Information System (INIS)

    The Shang Dynasty civilization in China is based on the development of the bronze techniques. A large amount of Shang Dynasty bronzes, excavated from Jiangxi, Hubei and Henan Provinces, have become a focus of world attention. However, the Shang Dynasty center was located at Zhenzhou and Anyang city areas, Henan Province, where no large copper ores have been found so far. Therefore, where did the huge ore material for casting the bronzes come from? It is an unsettled question paid attention by the archaeologists and scientists. 35 Shang Dynasty bronzes and 21 copper and lead ore materials aged in the Shang-Zhou Dynasty, the Spring-Autumn Period and the modern time, have been measured by the use of mass spectrometry. Based upon lead isotopic ratios, the ore material for casting the bronzes with the middle isotopic ratios of 207Pb/206Pb ranged in 0.8∼0.9 could come from the ancient copper mine of Tongling, Jiangxi Province and Tong Lushan , Hubei Province and that with the high isotopic ratios (>0.9) could be from the northern part of the Shang Empire, called 'Gongfang' in the historical records, e.g. today's Hebei and Liaoning Provinces. the others with the low isotopic ratios (238U/204Pb in the ore flux or in the magma

  2. Competencias básicas en Infantil, Primaria y Secundaria. Marco teórico.

    OpenAIRE

    Viana Orta, María Isabel

    2007-01-01

    Marco teórico del nuevo modelo educativo tras la aprobación de la LOE, basado en la adquisición y desarrollo de comptencias básicas. El material forma parte de cursos de formación permanente del profesorado.

  3. Muid võimalusi ei ole! / Kristina Norman, Marco Laimre ; intervjueerinud Elena Šmakova

    Index Scriptorium Estoniae

    Norman, Kristina, 1979-

    2009-01-01

    53. Veneetsia biennaalil "Making Worlds" ("Konstrueerides maailmu") Eestit esindavast Kristina Normani Tõnismäe pronkssõduri monumenti käsitlevast kunstiprojektist "After-War" ("Järelsõda"). Projekti kuraator Marco Laimre. Eesti ekspositsioon on avatud Palazzo Malipieros 6. juunist 22. novembrini. Biennaali nõukogu otsustas anda suured Kuldsed Lõvid elutöö eest Yoko Onole ja John Baldessarile

  4. The San Marcos River Habitat Conservation Plan: Using HCP's as a Tool for Ecological Restoration

    Science.gov (United States)

    Winters, J. M.; Howard, M. S.; Arsuffi, T. L.

    2005-05-01

    The San Marcos River in San Marcos, Hays County, Texas is a biologically unique system with several listed species found in the headwaters. Flowing from the Edwards Aquifer and the second largest spring system in Texas, the water is clear and thermally constant. The physical and biological character of the habitat within and surrounding the river has been severely degraded by human activity. As a means of dealing with the continued disturbance and finding a balance between human needs and conservation, the San Marcos River Habitat Conservation Plan was written as provided by Section 10(a) of the Endangered Species Act. The plan provides habitat mitigation for the fountain darter (Etheostoma fonticola), Comal Springs riffle beetle, (Heterelmis comalensis), and San Marcos salamander (Eurycea nana), while allowing for incidental take resulting from specific restoration and management projects. We used a science-based ecological/experimental approach to address some of the problems and optimize solutions, including restoration of stream banks damaged from overuse, planning for permanent access points and trails, removal of silt deposits caused by extensive flood control structures, wet-pond construction, managing flow, and the control of submerged and emergent non-native vegetation to improve habitat and enhance recreation.

  5. Las interpelaciones de la transmodernidad y la cuestión del marco categorial

    Directory of Open Access Journals (Sweden)

    Yamandú Acosta

    2013-11-01

    Full Text Available Se considera a las ciencias sociales y las humanidades desde una perspectiva crítica latinoamericanaa propósito de la integración, focalizando la cuestión del marco categorial desde las interpelaciones de latransmodernidad.

  6. El derecho de asilo en tanto derecho fundamental en el marco del Derecho Comnitario

    OpenAIRE

    Fonseca Morillo, Francisco J.

    2008-01-01

    1.- Introducción. 2.- La protección y el respeto de los derechos fundamentales en el ámbito del derecho comunitario. 3.- El derecho de asilo en el marco del derecho comunitario. 4.- El derecho de asilo como derecho fundamental....

  7. Teoría de los marcos relacionales y la trasformación de las funciones del estímulo

    OpenAIRE

    Simon Dymond; Bryan Roche; Ruth Anne Rehfeldt

    2005-01-01

    La teoría de los marcos de relaciones es una teoría y tecnología moderna del lenguaje y la cognición que hace gran énfasis en la trasformación de funciones de estímulo de acuerdo con las relaciones múltiples del estímulo. Revisamos la investigación reciente sobre la trasformación de las funciones de estímulo y argumentamos que la trasformación derivada posee importancia clínica, no solo porque da cuenta de la emergencia de nuevas respuestas ante estímulos previamente neutrales ...

  8. Pioneering farmers cultivating new lands in the North – The expansion of agrarian societies during the Neolithic and Bronze Age in Scandinavia

    DEFF Research Database (Denmark)

    Sørensen, Lasse

    2012-01-01

    Pioneering farmers cultivating new lands in the North – The expansion of agrarian societies during the Neolithic and Bronze Age in Scandinavia......Pioneering farmers cultivating new lands in the North – The expansion of agrarian societies during the Neolithic and Bronze Age in Scandinavia...

  9. Para uma Crítica da Razão Psicométrica

    Directory of Open Access Journals (Sweden)

    Patto Maria Helena Souza

    1997-01-01

    Full Text Available A partir da presença de testes e de laudos psicológicos na escola pública de 1º grau, o artigo discute, no marco teórico do materialismo histórico, aspectos epistemológicos e políticos do psicodiagnóstico.

  10. A Preliminary Study of Bronzes in the Kayao Culture%卡约文化青铜器初步研究

    Institute of Scientific and Technical Information of China (English)

    三宅俊彦

    2005-01-01

    A chronological study of its pottery suggests that the Kayao culture remains can be divided into the groups of Huangshui River and Yellow River valleys and each group fall into six phases.On this basis the typology and combination of bronzes in the Kayao culture can be further studied. The results indicate that bronze-making technology in the Huangshui River valley was higher than that in the Yellow River valley, and that the sexual difference of tomb-owners is reflected from the distinction of funeral objects. Furthermore, the chronological study of the Kayao's bronzes provides reference data for dating the phases of this culture. These bronzes possess three categories of cultural elements: the elements of their own, common elements of bronzes in the Central Plains and North China, and those in northern Eurasia.

  11. A green route for microwave synthesis of sodium tungsten bronzes NaxWO3 (0

    International Nuclear Information System (INIS)

    A green route has been developed for microwave synthesis of sodium tungsten bronzes NaxWO3 (02WO4, WO3 and tungsten powder. The hybrid microwave synthesis was carried out in argon atmosphere using CuO powder as the heating medium. Tungsten powder is used as the reducing agent instead of the alkali metal iodides previously used for the microwave synthesis of oxide bronzes. The prepared samples were characterized by powder X-ray diffraction, energy-dispersive X-ray analysis and scanning electron microscopy, and their phase constitutions, crystal structures and morphologies are in consistence with that in the literature. This synthesis method is simple, green and atom economic, and promising for preparation of other oxide bronzes and related compounds

  12. Development of a high Jc bronze route Nb3Sn conductor using Nb-Ta composite filaments

    International Nuclear Information System (INIS)

    For superconducting magnets generating fields above 10 tesla, multifilamentary Nb3Sn is the conductor of choice. There are two widely used methods of manufacturing these conductors, namely the internal Sn route and bronze process. Bronze route conductors can yield long piece lengths with consistent performances due to the mechanical compatibilities of the components compared to internal Sn conductors. Internal Sn designs require a soft low melting point Sn and is more difficult to be co-processed with the significantly harder Nb filaments. This paper summarizes the development of a bronze route Nb3Sn wire with high Jc using Nb-Ta composite filaments for use in advanced projects such as the International Thermonuclear Experimental Reactor (ITER)

  13. The lattice parameter of α-bronzes as a function of solute content: application to archaeological materials

    International Nuclear Information System (INIS)

    The lattice parameter of Cu substitutional solid solution--α-phase--has been studied in relation with the solute content. The investigation was conducted on pure binary Cu-Sn, industrial Cu-Sn-Zn alloys and archaeological bronzes. Lattice parameters and elemental compositions of the α-phase have been determined by X-ray diffraction and X-ray spectrometry. A linear relation between the unit cell constant and the atomic tin equivalent content in the α-phase has been evidenced and characterised, in fair agreement with Vegard's law. Addition of lead and trace elements has no significant effect on the results. Therefore, the tin equivalent content of the α-phase can be determined from XRD evaluation of the lattice parameter. As a consequence, a new approach is proposed for setting composition standards in α-(Cu-Sn) and α-(Cu-Sn-Zn) bronzes and application to characterization of ancient bronzes is discussed

  14. SUSCEPTIBILIDAD GENÉTICA AL CÁNCER:ALGUNAS CONSIDERACIONES BIOÉTICAS BAJO EL MARCO LEGAL VENEZOLANO

    Directory of Open Access Journals (Sweden)

    Flores Angulo Carlos JG

    2010-04-01

    Full Text Available

    El cáncer es una enfermedad que se caracteriza por la proliferación rápida e incontrolada de las células. Existen varios factores de riesgo asociados, entre ellos, el hereditario tal vez sea el más importante, ya que, aunque el fenotipo tiene una gran dependencia de las condiciones ambientales, la base de la carcinogénesis es el daño genético no letal. En este sentido, el estudio de los marcadores genéticos de susceptibilidad adquiere capital importancia, ya que estos permiten identificar a los individuos con alto riesgo genético, estimar su pronóstico y respuesta al tratamiento, adquiriendo la medicina un carácter más predictivo y preventivo. No obstante, esto podría desencadenar problemas éticos de gran impacto, especialmente difíciles de solucionar en una sociedad carente de un marco legal adecuado. Es importante, así,  realizar un análisis del Sistema Legal Venezolano (SLV que protege la información del genoma humano y sus repercusiones bioéticas. Para ello, se realizó una búsqueda e interpretación del marco normativo venezolano vigente, de publicaciones inherentes al cáncer, su susceptibilidad y tecnología diagnóstica. Las conclusiones derivadas son: 1 No es recomendable la oferta masiva de pruebas para la detección de riesgo genético debido a sus repercusiones psicosociales y laborales, 2 El desarrollo del SLV vinculado a la protección del genoma es bastante limitado, y 3 Es necesaria la adecuación del SLV al inminente desarrollo científico, para así controlar el impacto bioético de la información obtenida y garantizar Sobre la instrumentalización de la identidad en el marco de las luchas por el reconocimiento político de los pueblos indígenas en Colombia

    OpenAIRE

    Tobar Tovar, Carlos

    2014-01-01

    En este artículo plantearemos un abordaje a algunos fundamentos históricos y jurídicos del indigenismo en Colombia. Posteriormente, aludiremos a cómo se da el paso de la insurrección a la política describiendo el modo en que se evidencia la colectivización de los pueblos indígenas. Finalmente ofreceremos una lectura sobre la vivencia de la identidad étnica e introduciremos la idea de la instrumentalización de la identidad en el marco de las luchas sociales; también hablaremos del potencial tr...

  15. Analysis of the Portevin - Le Chatelier effect in tin bronzes at elevated temperatures

    Directory of Open Access Journals (Sweden)

    W. Ozgowicz

    2008-12-01

    Full Text Available Purpose: The aim of the present paper is the determination of the effect of the chemical composition and temperature of deformation of standardized tin bronzes and bronze modified with zirconium on the Portevin – Le Chatelier (PLC phenomenon, mainly basing on the shape of stress-strain curves within the temperature range of 100-300oC and observations of their structure. The reasons of the occurrence of such en effect are so far no fully known and explained and the opinions concerning is physical basis vary.Design/methodology/approach: Of essential design in this research is determination of the dependence of PLC effect on the chemical composition, temperature and strain rate and the preliminary heat treatment and grain size. The main method used in this investigation is tensile test at elevated temperature.Findings: The main conclusions are following: the PLC effect on tin bronzes with a micro-addition of zirconium in an amount of 0.01-0.05% depends the temperature of deformation in the tensile test in the range of 100-300oC and the chemical composition of the alloys; the type of serration revealed on the σ–ε curve depend mainly on the temperature of deformation and can be differ during the respective stages of the analyzed curves.Practical implications: In this paper implications for practice are not taken into consideration.Originality/value: In this paper an additive type of serration observed on the curves σ–ε, denoted by the symbol D, is new.

  16. Nanoscale building blocks in a novel lithium arsenotungsten bronze: Synthesis and characterization

    International Nuclear Information System (INIS)

    We report on a novel compound Li3AsW7O25 obtained by solid-state reaction and characterized by diffraction and spectroscopic methods. The bronze-type compound crystallizes in the orthorhombic space group Pbca with a=724.38(3) pm, b=1008.15(4) pm, c=4906.16(17) pm and Z=8. The structure is built up by chains of WO6 octahedra interconnected by AsO4 tetrahedra and WO6 octahedra forming a polyhedral arrangement as seen in intergrowth tungsten bronzes. The X-ray single crystal structure refinement allows solving the complex arsenotungstate framework. The powder neutron diffraction data analysis locates the lithium atoms. Thermal analysis showed that Li3AsW7O25 is stable up to its melting at 1135(3) K followed by a decomposition at 1182(5) K. The Kubelka–Munk treatment of the UV–vis spectrum revealed a wide band gap in the range of 2.84–3.40 eV depending on the presumed electron transition type. - Graphical abstract: Crystal structure of Li3AsW7O25 showing different schematic components. - Highlights: • A report on a novel compound Li3AsW7O25 obtained by solid-state reaction. • Chains and nano-blocks of WO6 octahedra and AsO4 tetrahedra formed a structure like intergrowth tungsten bronzes. • X-ray diffraction allowed solving the complex arsenotungstate framework. • Powder neutron diffraction data analysis locates the lithium atoms. • UV–vis spectrum revealed the band-gap

  17. On the degradation factors of an archaeological bronze bowl belonging to a private collection

    International Nuclear Information System (INIS)

    Highlights: • Bronze bowl from Iran belonging to a private collection. • Style and manufacturing consistent with the Achaemenid art (I century B.C.). • Modified Type I patinas. • Apparently continuous tenorite layer at the metal surface on the internal bowl side. • Fragmentation attributed to a severe intergranular attack. - Abstract: A bronze bowl belonging to a private collection, stylistically consistent with the Achaemenid art was investigated to determine the cause of the artwork local fragmentation. The corrosion products were characterised by energy dispersive X-ray fluorescence spectrometry (EDXRF), Raman spectroscopy and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The last technique was also used to determine the chemical composition of the alloy. The metallographic analysis showed that the bowl was obtained from a monophasic bronze alloy, containing about 11% tin and other elements in traces. The presence of an inhomogeneous microstructure with both thermal twin bands and slip lines was consistent with multiple hammering steps followed by partial annealing treatments. On the bowl a very limited chloride contamination was observed and chlorides were never detected in proximity to the metal. These findings and the morphological/compositional characteristics of the patinas permitted to classify that on the internal side of the bowl as a modified Type I morphology, while the patina on the external side of the bowl was less compact, so that it was judged borderline between a “noble” patina and a disfiguring one. On this side, a significant intergranular attack was found, reputed responsible for the fragmentation occurred

  18. On the degradation factors of an archaeological bronze bowl belonging to a private collection

    Energy Technology Data Exchange (ETDEWEB)

    Soffritti, C., E-mail: chiara.soffritti@unife.it [TekneHub, Department of Architecture, University of Ferrara, Via Quartieri 8, 44122 Ferrara (Italy); Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Fabbri, E., E-mail: elettra.fabbri@unife.it [Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Merlin, M., E-mail: mattia.merlin@unife.it [Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Garagnani, G.L., E-mail: gian.luca.garagnani@unife.it [Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); “A. Daccò” Corrosion and Metallurgy Study Centre, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); Monticelli, C., E-mail: cecilia.monticelli@unife.it [Department of Engineering, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy); “A. Daccò” Corrosion and Metallurgy Study Centre, University of Ferrara, Via Saragat 1, 44122 Ferrara (Italy)

    2014-09-15

    Highlights: • Bronze bowl from Iran belonging to a private collection. • Style and manufacturing consistent with the Achaemenid art (I century B.C.). • Modified Type I patinas. • Apparently continuous tenorite layer at the metal surface on the internal bowl side. • Fragmentation attributed to a severe intergranular attack. - Abstract: A bronze bowl belonging to a private collection, stylistically consistent with the Achaemenid art was investigated to determine the cause of the artwork local fragmentation. The corrosion products were characterised by energy dispersive X-ray fluorescence spectrometry (EDXRF), Raman spectroscopy and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). The last technique was also used to determine the chemical composition of the alloy. The metallographic analysis showed that the bowl was obtained from a monophasic bronze alloy, containing about 11% tin and other elements in traces. The presence of an inhomogeneous microstructure with both thermal twin bands and slip lines was consistent with multiple hammering steps followed by partial annealing treatments. On the bowl a very limited chloride contamination was observed and chlorides were never detected in proximity to the metal. These findings and the morphological/compositional characteristics of the patinas permitted to classify that on the internal side of the bowl as a modified Type I morphology, while the patina on the external side of the bowl was less compact, so that it was judged borderline between a “noble” patina and a disfiguring one. On this side, a significant intergranular attack was found, reputed responsible for the fragmentation occurred.

  19. Contextos funerários e estudo antropológico dos restos ósseos humanos dos hipogeus de Torre Velha 3 (São Salvador, Serpa): Uma aproximação ao estudo das comunidades humanas do Bronze do Sudoeste

    OpenAIRE

    Fidalgo, Daniel Filipe Ferreira

    2014-01-01

    O principal objectivo deste trabalho de investigação é aprofundar os dados conhecidos acerca das comunidades humanas que habitaram a região do Baixo Alentejo durante o Bronze Médio do Sudoeste (2070 – 1930 a.C. a 1170 – 1050 a.C.). Foi realizada uma análise da antropologia funerária e dos restos ósseos exumados de 21 dos 25 hipogeus registados em Torre Velha 3 (São Salvador, Serpa). Os restos ósseos humanos presentes nestas estruturas representam um total de 28 indivíduos, 2...

  1. Computed Tomography and Computed Radiography of late Bronze Age Cremation Urns from Denmark

    DEFF Research Database (Denmark)

    Harvig, Lise Lock; Lynnerup, Niels; Amsgaard Ebsen, Jannie

    2012-01-01

    To improve methods used to study prehistoric cremation rituals, cremation urns from the Danish late Bronze Age were examined using Computed Tomography and Computed Radiography (Digital X-ray). During microexcavation, the digital images were used as registration tool. Our results suggest that...... osteological ageing and sexing are more accurate when combining CT-images with excavated remains. Digital volume rendering further enables a compromised estimation of original cremation weight. Microexcavation is clearly a primary cause of bone fragmentation. Cremated remains affected by lower cremation...

  2. Compositional analyses of a Reutlingen Bronze Age sword discovered at Giurgiu, Romania

    CERN Document Server

    Olariu, A; Avram, A; Badica, T; Olariu, Agata; Alexandrescu, Emilian; Avram, Alexandru; Badica, Teodor

    2003-01-01

    The compositional scheme of a Bronze Age sword, found near the town of Giurgiu in Romania has been determined by the method of particle-induced X-ray emission (PIXE), at the tandem accelerator of the National Institute for Physics and Nuclear Engineering from Bucharest, Magurele, Romania. The results of the analyses and the comparison with the composition of other swords from the same geographic area, the Danubian plane from Bulgaria and Transylvania regions, show that the sword from Giurgiu could be relatively associated with the swords from Bulgaria, having also the same stylistic, temporal and geographical similitude.

  3. Strength of b3Sn intermetallic layers in bronze/niobium filaments composite material

    International Nuclear Information System (INIS)

    Tension tests have been used to estimate the strength of Nb3Sn intermetallic layer formed at the filament/matrix interface in the composite superconducting material, bronze(13 at.%Sn)/niobium filament. It is noted that the layer destruction starts with the formation of a group of cracks placed at a similar interval from each other, which are the reason for instability of sUperconducting properties in the composite system. The formula is given that connects the fracturing and superconducting properties, from which it follows that with the increase of layer thickness and its strength, the fracturing reduces, while superconducting properties improve

  4. ARCHAEOMETALLURGICAL STUDIES OF SPEAR HEADS AND ARROW HEADS OF THE MIDDLE BRONZE AGE SITES OF AZERBAIJAN

    OpenAIRE

    Hasanova, Aziza

    2015-01-01

    Quantitative spectroscopy analysis of spear heads and arrow heads of Middle Bronze Age sites of Azerbaijan (second part of the III to the middle of the II millennium BC) has been made to determine the type of the alloy taking into account the accepted limits of natural impurity in metals ( - 0.5% and more). The analyses have shown that copper is the basic materials in all of them. Metallurgical classification the results of sixteen analysis spear heads have shown three of them made of arsenic...

  5. Electrolytic surface hardening of steel,castiron and aluminium-bronze

    Directory of Open Access Journals (Sweden)

    Suhas Keshav Paknik a r

    2006-08-01

    Full Text Available Electrolytic hardening process w as developed in USSR in the 1950s. The process w as developed but w as not com m ercially exploited. There is no evidence of w ork done on this process in India. The author has done this originalw ork applied to different m aterials like steel, castiron and alum inum -bronze.This paper gives details ofm icrostructuraltransform ations along w ith hardness value achieved. There is vitalscope for this process to becom e viable for surfacehardening and selective hardening ofsm allcom ponents.

  6. Synthesis and structure of a quadratic oxygen bronze containing uranium of valence six

    International Nuclear Information System (INIS)

    (Nb7.6U2.4)(Ba5.2K0.8)O30 is a quadratic bronze with space group P4bm and lattice parameters a = 12.608(5) and c = 4.012(2) A, Z=1. The structure of a single crystal was refined to R = 0.056 (RW = 0.072) for 967 independent reflections with I ≥ 3σI. The U6+ ion is located inside octahedral sites with Nb5+ and Nb4+. (orig.)

  7. Characterization and Photocatalytic Activity of KSr_2Nb_5O_(15) with Tungsten Bronze Structure

    Institute of Scientific and Technical Information of China (English)

    ZHANG Gaoke; LI Yiqiu; WANG Junting; TU Haibin; YU Xinyi

    2009-01-01

    Tungsten bronze(TB)type potassium strontium niobate KSr_2Nb_5O_(15) was prepared by solid-state reaction method,and was characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM)and UV-vis diffuse spectrum.The photocatalyst shows high photocatalytic activity of photodegrading acid red G.The effects of photocatalyst dosage and initial concentration of acid red G on the photodegradation process were studied.The kinetics of photocatalytic degradation of acid red G by KSr_2Nb_5O_(15) catalyst follows the first order reaction.

  8. Micro-EDXRF surface analyses of a bronze spear head: Lead content in metal and corrosion layers

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, E. [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Departamento de Conservacao e Restauro, Faculdade de Ciencias e Tecnologia da Universidade Nova de Lisboa, Quinta da Torre, 2829-516 Monte de Caparica (Portugal)], E-mail: elin@itn.pt; Valerio, P.; Araujo, M.F. [Instituto Tecnologico e Nuclear, Estrada Nacional 10, 2686-953 Sacavem (Portugal); Senna-Martinez, J.C. [Instituto de Arqueologia, Faculdade de Letras da Universidade de Lisboa, Cidade Universitaria, Campo Grande, 1600-214 Lisbon (Portugal)

    2007-09-21

    A bronze spear head from Central Portugal dated to Late Bronze Age has been analyzed by non-destructive micro-EDXRF in the metal surface and corrosion layers. The artifact had previously been analyzed using a conventional EDXRF spectrometer having a larger incident beam. The quantification of the micro-EDXRF analyses showed that lead content in corrosion layers can reach values up to four times higher than the content determined in the metal surface. Results obtained with the higher energy incident beam from the EDXRF equipment, although referring mainly to the corrosion layers, seem to suffer some influence from the surface composition of the metallic alloy.

  9. 夏商周青铜器铅同位素示踪研究数据库的构建%A Lead Isotope Ratio Data Base of Ancient Chinese Bronzes

    Institute of Scientific and Technical Information of China (English)

    金正耀

    2005-01-01

    A data base of lead isotope ratio of ancient Chinese bronzes is set up. There are 2 888 members, including bronze objects, casting remains, and related ores, etc. in the file. The file contents of data base are made from analysis work on Chinese bronze previously carried out in several laboratories in China, Japan and USA. The main body of the file contents is formed from records, analysis data, reference documents, and images. The data base is designed for sharing information in provenance study on raw metal material for bronze production in China Bronze Age.

  10. Una perspectiva filosófica de la ciencia hoy en día: Entrevista con Alfredo Marcos

    OpenAIRE

    Maia, Eduardo Cesar; Roaro, Jorge

    2012-01-01

    [ES] En el invierno de 2012, el Prof. Alfredo Marcos respondió una serie de preguntas sobre filosofía de la ciencia para el primer número de Disputatio. En esta entrevista, Alfredo Marcos presenta los fundamentos históricos y filosóficos de la ciencia en sentido amplio y nos presenta cómo funciona su aplicación en diferentes ámbitos: comunicación de la ciencia, investigación clínica, política ambiental, poética de la ciencia. [EN] At the winter of 2012, the Prof. Dr. Alfredo Marcos answere...

  11. Neopentecostalismo na mentalidade do povo brasileiro: um deslocamento da fé para o mercado

    OpenAIRE

    Paulo Passos

    2010-01-01

    A ascensão das denominações pentecostais no mercado formal da religiosidade brasileira simboliza uma verdadeira quebra de paradigmas. Da marginalidade, do estigma de “seita” que caracteriza este segmento, passaram a ocupar um plano privilegiado no campo econômico e espiritual. Essa exponencial visibilidade social em detrimento de outras denominações religiosas, sobretudo da católica, baliza o marco contextual dessa pesquisa.  Entremeio a uma inusitada percepção espiritual da pós-modernidade, ...

  12. Conversações: modelo cibernético da construção do conhecimento/realidade

    OpenAIRE

    Pellanda Nize Maria Campos

    2003-01-01

    Este artigo trata da discussão da aplicação de uma metodologia baseada em princípios cibernéticos com um grupo de pesquisadoras em educação no processo de construção de conhecimento por meio da Dinâmica das Conversações. Conversação é um dos pressupostos básicos da teoria de Humberto Maturana sobre Biologia da Cognição, a qual constitui o núcleo do marco teórico deste trabalho.

  13. Marco jurídico de la política de telecomunicaciones

    OpenAIRE

    Carlos Labaure Aliseris

    2014-01-01

    Introducción. Generalidades. Concepto de telecomunicación. Monopolio y competencia. Políticade telecomunicaciones. Noción e instrumentos. Evolución de las políticas de telecomunicaciones. Marco jurídico de las telecomunicaciones. Régimen general. Regímenes específicos.Nos vamos a referir al marco jurídico de la política de telecomunicaciones. Se trata de una regulación sectorial, fijada por el Estado, para una actividad en que actúan sujetos públicos y privados.Dicha regulación ha estado suje...

  14. Marco Martiniello, Penser l’ethnicité. Identité, culture et relation sociales

    OpenAIRE

    Rochereuil, Aurélie

    2013-01-01

    Les médias traitent fréquemment de violence ou de conflits dits « ethniques », ayant lieu en Europe ou dans d’autres pays du monde. Dans ce contexte, Marco Martiniello, directeur de recherches FNRS et directeur du Centre d’études de l’ethnicité et des migrations de l’Université de Liège, nous offre « un examen du concept d’ethnicité ». Cet ouvrage permet de comprendre dans quelle mesure les sciences sociales peuvent parler de l’ethnicité et l’étudier. Marco Martiniello définit l’ethnicité, se...

  15. Marco Común Europeo de Referencia en el Aprendizaje de Lenguas Extranjeras

    OpenAIRE

    Díaz-Corralejo, Joaquín

    2003-01-01

    En 1990, el Consejo de Europa propuso a varios paises la experimentación del nuevo entorno metodológico para la enseñanza / aprendizaje de las lenguas en el siglo XXI: el Marco Común Europeo de Referencia para el Aprendizaje, la Enseñanza y la Evaluación de las lenguas extranjeras. Más de quince países respondieron a este reto, España no estaba entre ellos. En 2001, se presenta la traducción al español de dicho Marco. El presente articulo se centra en la descripción de los fimdamentos meto...

  16. Ecología política y agroecología: marcos cognitivos y diseño institucional

    OpenAIRE

    Garrido Peña, Francisco

    2011-01-01

    La ideología política y el modelo institucional producen “marcos cognitivos” y “marcos institucionales” que favorecen uno u otro tipo de elecciones y conductas. La Ecología Política como generadora de marcos cognitivos (ideología) y marcos institucionales (normas y programas de gobierno). En este trabajo tratamos de identificar las virtualidades que para el desarrollo de la agroecología tiene el contar con marco cognitivos e institucionales afines como los que proponen la Ecolo...

  17. Las Lunas (Yuncler, Toledo. A Bronze Age hoard with metallic materials from the southern Iberian Meseta

    Directory of Open Access Journals (Sweden)

    Urbina Martínez, Dionisio

    2010-06-01

    Full Text Available Here we present the results of the preliminary study carried out on a new group of metallic materials of the Final Bronze Age, recovered at the end of 2008 in the archaeological excavations at the settlement of Las Lunas (Yuncler, Toledo, Spain. Its geographical situation far away from the main zones of distribution of this type of finds, the singularity of the materials, and the evidence of Atlantic and Mediterranean relations make these materials a remarkable sample for the study of the Final Bronze Age in the centre of the Iberian Peninsula.

    Se exponen los resultados del primer estudio realizado sobre un nuevo conjunto de materiales metálicos del Bronce Final recuperado a finales de 2008 en las excavaciones arqueológicas del yacimiento de Las Lunas (Yuncler, Toledo, España. La localización geográfica del hallazgo, lejos de las principales zonas de dispersión conocidas para este tipo de conjuntos, la singularidad de los objetos que integra, y las relaciones atlánticas y mediterráneas que evidencian sus materiales, lo convierten en un ejemplo destacado para el estudio de este período en el centro de la Península Ibérica.

  18. Thermal conductance at millikelvin temperatures of woven ribbon cable with phosphor-bronze clad superconducting wires

    Science.gov (United States)

    Woodcraft, Adam L.; Ventura, Guglielmo; Martelli, Valentina; Holland, Wayne S.

    2010-08-01

    Woven Nomex® ribbon cables made up with superconducting niobium-titanium wire are used at millikelvin temperatures in many large cryogenic instruments. It is important to know how much heat in transmitted down such cables. However, the conductivity of the materials used is not well known. Another problem is that the wires are normally clad with alloys which exhibit some magnetism. This is a potential problem for instruments employing superconducting detectors. A safe non-magnetic alternative to the usual materials is phosphor-bronze clad niobium-titanium wiring. However, there is little experience with such wires. We have therefore measured the conductance of a ribbon cable made up with these wires. The measured values are in good agreement with our predictions, suggesting that the values we have used to model the cable are sufficiently accurate, and could therefore be used to predict the performance of ribbon cables using other cladding materials, so long as the conductivity of the cladding is reasonably well known. As part of our analysis, we consider the likely variation in thermal conductivity values for C51000 phosphor bronze caused by legitimate variations in composition.

  19. Neutron activation analysis of Lerna ceramics (Greece) at Early Bronze Age: local production and trade exchanges

    International Nuclear Information System (INIS)

    Neutron activation analysis is a powerful tool for determining the provenance of ancient ceramics. A sophisticated analytical system for gamma-ray spectrometry, designed specifically for the chemical analysis of ceramics by thermal neutron activation, was used to determine the concentrations of twenty elements in samples of ancient pottery. The measurements were made relative to the standard pottery of Perlman and Asaro. The purpose of the work was to study the production of fine pottery at the settlement of Lerna, in the Argolid of Greece, during the Early Bronze Age (third millennium BC). About half of the 50 samples analysed formed the major compositional group, which was attributed to Lerna. It included, besides the majority of the samples from the second phase of the Early Bronze Age (Lerna III), several samples from the third phase (Lerna IV); that is, from levels immediately succeeding the great destruction which marks the end of the Lerna III settlement. A small number of objects forms a second group of local origin and includes 4 of the 5 clay sealings sampled. Among the archaeologically unusual objects, several could be attributed to Lerna, while others were characterized as imports

  20. The atmospheric corrosion of quaternary bronzes: An evaluation of the dissolution rate of the alloying elements

    Science.gov (United States)

    Bernardi, E.; Chiavari, C.; Martini, C.; Morselli, L.

    2008-07-01

    A comparative evaluation of the corrosion behaviour of a G85 bronze in acid rain solutions was performed. As weathering technique, a wet dry device was used to simulate a cyclic exposure to stagnant rain. The weathering solutions were a collected natural rain and an artificial solution reproducing the natural rain. The solutions were periodically monitored as concerns pH and metallic ion concentrations. On the aged specimens, surface studies were performed through OM, SEM and Raman analyses. At the end of weathering tests (40 days), weight loss measurements were carried out. The aim of this work was to examine the reproducibility in laboratory of the corrosive conditions determined by a natural acid rain. The final goal of this research is to investigate the dissolution of a quaternary alloy exposed to acid rains. The results showed slightly different corrosion behaviours as a consequence of the exposure to natural or synthetic rain. Concerning the mechanism of corrosion of G85 bronze, the innovative approach adopted in this study allowed one to point out the contribution of each alloying element to the general corrosion. Actually, while Cu and Pb progressively form insoluble corrosion compounds, Zn continuously dissolves, without forming detectable insoluble products. The absence of dissolved tin is remarkable.

  1. Generation of nanoparticles of bronze and brass by laser ablation in liquid

    International Nuclear Information System (INIS)

    Nanoparticles of brass and bronze are generated by ablation of corresponding bulk targets in liquid ethanol. The experiments were performed using three pulsed lasers with different pulse duration: ytterbium fiber laser (80 ns), a Neodymium:YAG laser (10 ps), and femtosecond Ti:sapphire laser (200 fs). The generated nanoparticles (NPs) are characterized by UV–vis absorption spectroscopy, X-ray diffractometry, Raman scattering, and Transmission Electron Microscopy. The size of generated NPs lies in the range 10–25 nm depending on the laser source. The X-ray diffractometry reveals the change of phase composition of brass NPs compared to the initial target in case of ablation with 80 ns laser source, while with 10 ps laser pulses this effect is less pronounced. Brass NPs generated with pico- and femtosecond laser radiation show the plasmon resonance in the vicinity of 560 nm and no plasmon peak for NPs generated with longer laser pulses. Raman analysis shows the presence of Cu2O in generated NPs. The stability of generated NPs of both brass and bronze to oxidation is compared to that of Cu NPs generated in similar experimental conditions.

  2. $Nb_{3}Sn macrostructure, microstructure, and property comparisons for bronze and internal Sn process strands

    CERN Document Server

    Lee, P J; Larbalestier, D C

    2000-01-01

    The variation in irreversibility field, B*(T), with temperature has been measured for Nb/sub 3/Sn superconducting strands manufactured for ITER using vibrating sample and SQUID magnetometers. The high performance strands were developed for both high transport critical current density, J/sub c/, and low hysteresis loss. Despite a wide variety of designs and components, the strands could be split into two distinctive groups, based on the extrapolated irreversibility fields, which lie about 10% lower than the upper critical field. "Bronze-process" strands exhibited consistently higher B*(T) (28 T to 31 T) compared with "internal Sn" process (24 T to 26 T) conductors. The intrinsic critical current density of the superconductor, J/sub c (sc)/, and the specific pinning force of the grain boundaries, Q/sub gb/, were evaluated using the measured J/sub c/, and image analysis of the macro- and micro-structures. A bronze-processed Nb(-Ta)/sub 3 /Sn was found to have a higher J/sub c(sc)/ but lower Q/sub gb/ than Nb/sub...

  3. Comparison of phosphor bronze metal sheet produced by twin roll casting and horizontal continuous casting

    Science.gov (United States)

    Hwang, J. D.; Li, B. J.; Hwang, W. S.; Hu, C. T.

    1998-08-01

    Much effort recently has been expended to study the strip casting process used to produce thin metal strip with a near final thickness. This process eliminates the need for hot rolling, consumes less energy, and offers a feasible method of producing various hard-to-shape alloys. The finer microstructure that results from the high cooling rate used during the casting process enhances mechanical properties. In this study, strips of phosphor bronzes (Cu-Sn-P) metal were produced using a twin roll strip casting process as well as a conventional horizontal continuous casting (HCC) process. The microstructures, macrosegregations, textures, and mechanical properties of the as-cast and as-rolled metal sheet produced by these two methods were examined carefully for comparative purposes. The results indicate that cast strip produced by a twin roll caster exhibit significantly less inverse segregation of tin compared to that produced by the HCC process. The mechanical properties including tensile strength, elongation, and microhardness of the products produced by the twin roll strip casting process are comparable to those of the HCC processed sheet. These properties meet specifications JIS H3110 and ASTM B 103M for commercial phosphor bronze sheet. The texture of the as-rolled sheet from these two processes, as measured from XRD pole figures, were found to be virtually the same, even though a significant difference exists between them in the as-cast condition.

  4. Las lagunas de Ruidera during the Bronze Age: a hierarchical territory

    Directory of Open Access Journals (Sweden)

    Ocaña Carretón, Andrés

    2002-06-01

    Full Text Available This paper shows the first results of a research project that aims to analyse the spatial relationship betwen the natural resources and the settlements in the Upper Guadiana River (South Meseta, Spain. The data obtained will be used to understand the productive system of the communities which lived in this territory during the Copper and Bronze Ages. In particular the settlement pattern during the Bronze Age is analysed in the Nature Reserve of Lagunas de Ruidera. This shows a territorial hierarchical structure and allows us to understand the emergence of social complexity within this territory.

    Este artículo muestra los primeros resultados de un proyecto que tiene por objeto analizar la relación espacial entre los recursos y los asentamientos en el Alto Guadiana como aproximación a los sistemas productivos de las comunidades que habitaron este territorio durante el Calcolítico y la Edad del Bronce. En concreto, se analiza el patrón de asentamiento durante la Edad del Bronce en el Parque Natural de las Lagunas de Ruidera, el cual indica la existencia de una ocupación jerárquica del territorio como reflejo de la existencia de un cierto grado de complejidad social.

  5. A Roman bronze statuette with gilded silver mask from Sardinia: an EDXRF study

    Science.gov (United States)

    Cesareo, Roberto; Brunetti, Antonio; D'Oriano, Rubens; Canu, Alba; Demontis, Gonaria Mattia; Celauro, Angela

    2013-12-01

    A Roman bronze statuette from the 2nd Century BC was recovered from a nuragic sanctuary close to Florinas, in the north of Sardinia. The facial portion of the statuette is covered by a silver mask, partially gilded and attached to the bronze by tin-lead welding. The silver mask was carefully analyzed by portable energy-dispersive X-ray fluorescence (EDXRF), a non-destructive and non-invasive method. The aim of the analysis was to reconstruct the layered structure of the silver gilt mask, and to determine homogeneity and thickness of the gold, silver and lead-tin sheets. This is possible by using the internal ratio of the X-ray lines, i.e. starting from the surface, Au (L α/L β), Ag (K α/K β), Au-L α/Ag-K α and Pb (L α/L β).The results were compared with those obtained with simulated X-ray spectra, obtained both experimentally and by using the Monte Carlo simulation technique.

  6. Shellfish from the Bronze Age Site of Clos des Châtaigniers (Mathieu, Normandy, France

    Directory of Open Access Journals (Sweden)

    Caroline Mougne

    2014-09-01

    Full Text Available This article provides initial results on the use of shellfish by the inhabitants of Clos des Châtaigniers, Normandy (France during the Late Bronze Age. The settlement is located at Mathieu, 10km from the coast. The French National Institute of Preventive Archaeological Research (INRAP conducted excavations on this site in 2010, under the direction of David Giazzon. A semi-circular domestic enclosure from the end of the Late Bronze Age was discovered. The diet of the inhabitants of Mathieu was partly based on mussels, which were found in large quantities. These shells were collected at low tide on a rocky to muddy/rocky shore. They were then transported inland to be eaten fresh or processed. Other marine invertebrates were also present on this site. Some of them were collected with the mussels. In fact, they were mixed with or fixed to this bivalve. Many other small fragments of shells are present on the site and could have come from the stomach contents of fish.

  7. Florida’s primary results: a boring story with a sad ending for Senator Marco Rubio

    OpenAIRE

    Darlington, Rolda L.

    2016-01-01

    With 99 delegates, Florida is one of the most important states in this stage of the presidential primary season. Tuesday’s Republican primary saw Donald Trump win all but one of the Sunshine State’s 67 counties, and all of its delegates. Rolda L. Darlington writes that while the results were not surprising, they were devastating for the state’s US Senator Marco Rubio, who had been banking on a win there to stay in the presidential nomination race.

  8. Kaasaegses kunstis valitseb turvalisus / Marco Scotini, Andris Brinkmanis ; intervjueerinud Eero Epner

    Index Scriptorium Estoniae

    Scotini, Marco, 1964-

    2010-01-01

    Intervjuu Milano Nuova Accademia di Belle Art'i visuaalkunstide ja kuraatoriõppe osakonna juhataja, kaasaegse kunsti ajaloo ja kuraatoriõppe professori Marco Scotini ja sama akadeemia õppejõu Andris Birkmanisega. M. Scotini pidas Kumus loengu "Kuraator loomemajanduse ajastul. Teisel pool institutsionaalset kriitikat". Muutunud kaasaja kunstimaailmast: institutsioonide kontrollist, estetiseeritud kunsti valitsemisest biennaalidel, riigi kontrollimehhanismi asendumisest majanduslikuga, kuraatoritööst, retrospektiivnäituste rohkusest jm.

  9. PRIDE and MarcoPolo-R: VLBI applications for Near-Earth Asteroids science

    Science.gov (United States)

    Cimo, G.; Molera-Calves, G.; Duev, D. A.; Pogrebenko, S. V.; Bocanegra Bahamon, T.

    2012-09-01

    The core of the Planetary Radio Interferometry and Doppler Experiment (PRIDE) is the accurate estimation of the state-vector of a spacecraft using Very Long Baseline Interferometry (VLBI) tracking. In this contribution, we will describe the technique and the technical requirements as well as the multidisciplinary scientific outcome of PRIDE as a part of the ESA mission MarcoPolo-R towards the Near-Earth Asteroids.

  10. Genetic variants of MARCO are associated with susceptibility to pulmonary tuberculosis in a Gambian population

    OpenAIRE

    Lack, Nathan A.; Bowdish, Dawn M. E.; Sakamoto, Kaori; Hill, Philip C.; Sirugo, Giorgio; Newport, Melanie J.; Gordon, Siamon; Hill, Adrian V. S.; Vannberg, Fredrick O.

    2013-01-01

    Background The two major class A scavenger receptors are scavenger receptor A (SRA), which is constitutively expressed on most macrophage populations, and macrophage receptor with collagenous structure (MARCO), which is constitutively expressed on a more restricted subset of macrophages, (e.g. alveolar macrophages) but whose expression increases on most macrophages during the course of infection. Although the primary role of SRA appears to be clearance of modified host proteins and lipids,...

  11. Dr. Marco Marra: Pioneer and Visionary in Cancer Genomics Research | Office of Cancer Genomics

    Science.gov (United States)

    Dr. Marco Marra is a highly distinguished genomics and bioinformatics researcher. He is the Director of Canada’s Michael Smith Genome Sciences Centre at the BC Cancer Agency and holds a faculty position at the University of British Columbia. The Centre is a state-of-the-art sequencing facility in Vancouver, Canada, with a major focus on the study of cancers.  Many of their research projects are undertaken in collaborations with other Canadian and international institutions.

  12. Investigation on corrosion stratigraphy and morphology in some Iron Age bronze alloys vessels by OM, XRD and SEM-EDS methods

    Science.gov (United States)

    Oudbashi, Omid; Hasanpour, Ata; Davami, Parviz

    2016-04-01

    The recently study of the corrosion in some bronze artefacts from the Sangtarashan Iron Age site, western Iran, was established to identify corrosion morphology and mechanism in these objects. The corrosion layers in 22 samples were studied by optical microscopy, scanning electron microscopy-energy-dispersive X-ray spectroscopy and X-ray diffraction methods. The results showed that a thin corrosion crust has formed on the surface of bronzes with a triple-layer structure, including two internal and one external corrosion layers. The formation of these layers is due to copper leaching from the bronze surface. The internal corrosion part has been a compact, tin-rich corrosion/oxidation product (noble patina) with some evidences from original metallurgical aspects of the bronze as well as a very thin layer beneath the tin-rich layer. External corrosion products have been identified as basic copper carbonates, malachite and azurite. Based on the results, the corrosion morphology in the Sangtarashan Iron Age bronzes is due to long-term burial in an appropriate environment in a moderately corrosive soil. Although it is the first time to investigate Iron Age bronzes from Iran, this corrosion morphology is partially similar to type I corrosion morphology observed in archaeological bronze objects; nevertheless, some deviations are visible in comparison with previously established patterns.

  13. Determination of concentrations of minor and micro elements in ancient bronze drums artifacts samples by KO-standardization method of neutron activation analysis

    International Nuclear Information System (INIS)

    The study aims to get a lot information about manufacturers of ancient bronze artifacts and ancient civilization. By KO-standardization method of neutron activation analysis developed in the Nuclear Research Institute, the concentrations of Au, Ag, As, Zn, Sb, Sn elements in ancient bronze alloy samples of 99 bronze artifacts from many excavated archaeological sites at the provinces in Vietnam were determined with uncertainties about ±10%. These elemental concentrations have been utilized in a statistical analysis procedure in order to determine similarities and correlation between the various samples. Th abnormal high of concentrations of noble metals as Au, Ag in ancient bronze indicates that the ancient metallurgists had been interested in role of these metals on sound quality of bronze artifacts. Especially, the concentrations of As in many samples are very high even at about 10%. This gives an evidence that in ancient time the humankind could use bronze As alloy in order to improve quality when they had produced bronze artifacts. (author)

  14. Uranium-series isotopes transport in surface, vadose and ground waters at San Marcos uranium bearing basin, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    In the U deposit area at San Marcos in Chihuahua, Mexico, hydrogeological and climatic conditions are very similar to the Nopal I, Peña Blanca U deposit, 50 km away. The physicochemical parameters and activity concentrations of several 238U-series isotopes have been determined in surface, vadose and ground waters at San Marcos. The application of some published models to activity ratios of these isotopes has allowed assessing the order of magnitude of transport parameters in the area. Resulting retardation factors in San Marcos area are Rf238 ≈ 250–14,000 for the unsaturated zone and ≈110–1100 for the saturated zone. The results confirm that the mobility of U in San Marcos is also similar to that of the Nopal I U deposit and this area can be considered as a natural analog of areas suitable for geologic repositories of high-level nuclear waste.

  15. 48 CFR 252.216-7000 - Economic price adjustment-basic steel, aluminum, brass, bronze, or copper mill products.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Economic price adjustment... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions And Clauses 252.216-7000 Economic price...), use the following clause: Economic Price Adjustment—Basic Steel, Aluminum, Brass, Bronze, or...

  16. MODELING OF LIGATURE DISSOLUTION IN COPPER MELT AT SMELTING OF CHROMIC BRONZES AND OPTIMIZATION OF THEIR PRODUCTION PROCESS

    OpenAIRE

    F. G. Lovshenko; G. F. Lovshenko; B. B. Hina; I. A. Lozikov

    2015-01-01

    The results of modeling and their experimental-industrial test of alloy dissolution in the form of elementary chrome, cast and mechanically doped alloys «copper-chrome» system in copper melt at melting of chrome bronzes are given, the process of their production is optimized.

  17. Variety in cereal cultivation in the Late Bronze and Early Iron Ages in relation to environmental conditions

    Czech Academy of Sciences Publication Activity Database

    Dreslerová, Dagmar; Kočár, Petr; Chuman, T.; Šefrna, L.; Poništiak, Š.

    2013-01-01

    Roč. 40, č. 4 (2013), s. 1988-2000. ISSN 0305-4403 Institutional research plan: CEZ:AV0Z80020508 Institutional support: RVO:67985912 Keywords : crop husbandry * charred cereal grains * environment * weather * soils * Late Bronze Age/Early Iron Age Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 2.139, year: 2013

  18. 3D scanning and printing as conversation tools: an innovative treatment of a vandalized bronze statue, The Thinker by Rodin

    NARCIS (Netherlands)

    T. Beentjes; R. van der Molen

    2011-01-01

    This contribution discusses the innovative treatment of a severely vandalized bronze sculpture, The Thinker by Auguste Rodin, from the Singer Museum in Laren, The Netherlands. Additional aspects of this controversial treatment such as decision making and documentation are also discussed. In 2007 the

  19. Anomalously deep and fast failure of copper and bronze under the action of the corrosion products existing on them

    Science.gov (United States)

    Pozhidaeva, S. D.; Eliseeva, A. Yu.; Ivanov, A. M.

    2015-12-01

    When the corrosion products on copper and bronze are in close contact with a diluted aqueous solution of hydrochloric acid and atmospheric oxygen, they rapidly transform into effective metal (alloy) oxidizers, which provide rapid and deep metal consumption. The metal can be almost fully consumed in a reasonable technological time provided the accumulated solid phase of the products is periodically removed.

  20. Copper and tin isotopic analysis of ancient bronzes for archaeological investigation: development and validation of a suitable analytical methodology.

    Science.gov (United States)

    Balliana, Eleonora; Aramendía, Maite; Resano, Martin; Barbante, Carlo; Vanhaecke, Frank

    2013-03-01

    Although in many cases Pb isotopic analysis can be relied on for provenance determination of ancient bronzes, sometimes the use of "non-traditional" isotopic systems, such as those of Cu and Sn, is required. The work reported on in this paper aimed at revising the methodology for Cu and Sn isotope ratio measurements in archaeological bronzes via optimization of the analytical procedures in terms of sample pre-treatment, measurement protocol, precision, and analytical uncertainty. For Cu isotopic analysis, both Zn and Ni were investigated for their merit as internal standard (IS) relied on for mass bias correction. The use of Ni as IS seems to be the most robust approach as Ni is less prone to contamination, has a lower abundance in bronzes and an ionization potential similar to that of Cu, and provides slightly better reproducibility values when applied to NIST SRM 976 Cu isotopic reference material. The possibility of carrying out direct isotopic analysis without prior Cu isolation (with AG-MP-1 anion exchange resin) was investigated by analysis of CRM IARM 91D bronze reference material, synthetic solutions, and archaeological bronzes. Both procedures (Cu isolation/no Cu isolation) provide similar δ (65)Cu results with similar uncertainty budgets in all cases (±0.02-0.04 per mil in delta units, k = 2, n = 4). Direct isotopic analysis of Cu therefore seems feasible, without evidence of spectral interference or matrix-induced effect on the extent of mass bias. For Sn, a separation protocol relying on TRU-Spec anion exchange resin was optimized, providing a recovery close to 100 % without on-column fractionation. Cu was recovered quantitatively together with the bronze matrix with this isolation protocol. Isotopic analysis of this Cu fraction provides δ (65)Cu results similar to those obtained upon isolation using AG-MP-1 resin. This means that Cu and Sn isotopic analysis of bronze alloys can therefore be carried out after a single chromatographic

  1. INSPIRE and MarCO - Technology Development for the First Deep Space CubeSats

    Science.gov (United States)

    Klesh, Andrew

    2016-07-01

    INSPIRE (Interplanetary NanoSpacecraft Pathfinder In a Relevant Environment) and MarCO (Mars Cube One) will open the door for tiny spacecraft to explore the solar system. INSPIRE serves as a trailblazer, designed to demonstrate new technology needed for deep space. MarCO will open the door for NanoSpacecraft to serve in support roles for much larger primary missions - in this case, providing a real-time relay of for the InSight project and will likely be the first CubeSats to reach deep space. Together, these four spacecraft (two for each mission) enable fundamental science objectives to be met with tiny vehicles. Originally designed for a March, 2016 launch with the InSight mission to Mars, the MarCO spacecraft are now complete and in storage. When launched with the InSight lander from Vandenberg Air Force Base, the spacecraft will begin a 6.5 month cruise to Mars. Soon after InSight itself separates from the upper stage of the launch vehicle, the two MarCO CubeSats will deploy and independently fly to Mars to support telecommunications relay for InSight's entry, descent, and landing sequence. These spacecraft will have onboard capability for deep space trajectory correction maneuvers; high-speed direct-to-Earth & DSN-compatible communications; an advanced navigation transponder; a large deployable reflect-array high gain antenna; and a robust software suite. This talk will present an overview of the INSPIRE and MarCO projects, including a concept of operations, details of the spacecraft and subsystem design, and lessons learned from integration and test. Finally, the talk will outline how lessons from these spacecraft are already being utilized in the next generation of interplanetary CubeSats, as well as a brief vision of their applicability for solar system exploration. The research described here was carried out at the Jet Propulsion Laboratory, Caltech, under a contract with the National Aeronautics and Space Administration (NASA).

  2. THE RELATIONSHIP BETWEEN EGYPT AND PALESTINE IN THE MIDDLE BRONZE AGE (CA.2000-1550/1500 BCE.)

    Institute of Scientific and Technical Information of China (English)

    GuoDantong

    2004-01-01

    The relationship between Egypt and Palestine during the Bronze Age has been discussed since the 1940s. For the period of the Middle Bronze Age, the problem is both chronological and interpretative. The end of the Middle Bronze Age is fixed by the initial military activities of Dynasty 18 in Palestine around the end of the 16th century BCE. But the dates for the beginning of this period and the transition from one archaeological phase to another are still debated. Lacking a generally accepted solution, the chronology adopted here is that of Dever --- the transition from MB Ⅰ to MB Ⅱ occurred around 1800 BCE,

  3. Un estudio del dolor en el marco de la conducta verbal: de las aportaciones de W. E. Fordyce a la Teoría del Marco Relacional (RFT

    Directory of Open Access Journals (Sweden)

    Olga Gutiérrez Martínez

    2006-01-01

    Full Text Available En este estudio teórico se presenta una aproximación al análisis de los eventos privados en general y del dolor en particular desde una perspectiva funcionalcontextual bajo las aportaciones recientes de la conducta verbal, las relaciones arbitrarias entre eventos y la derivación de funciones psicológicas. Se hace una revisión de cómo los analistas de conducta han abordado el estudio del dolor como factor de control de otros comportamientos y, partiendo de la integración de estas aportaciones con los recientes avances del análisis de la conducta verbal, se propone la Teoría del Marco Relacional (RFT como formulación mejor articulada a la hora de ofrecer una explicación contextual del dolor. A raíz de la investigación en marcos relacionales y regulación verbal, se describe un novedoso planteamiento de los problemas clínicos de dolor como formas del trastorno de evitación experiencial (TEE que supone una aproximación a la psico(patología más parsimoniosa que la tradicional basada en la clasificación sindrómica. Además, son examinados los avances terapéuticos que se han derivado de esta concepción verbal-relacional de los problemas psicológicos, presentándose la terapia de aceptación y compromiso (ACT como un sistema terapéutico dirigido a alterar las clases de regulación verbal inefectivas y favorecer actuaciones ajustadas a los valores personales.

  4. GPR Surveys for Archaeological Investigation in a Bronze Age site from NW Portugal

    Science.gov (United States)

    Gonçalves, L.; Sampaio, H. A.; Bettencourt, A. M. S.; Alves, M. I. C.

    2012-04-01

    This work describes the use of Ground-penetrating Radar (GPR) surveys in the identification and mapping of subtle cultural remains, from Pego Late Bronze Age settlement, located near the city of Braga, in NW Portugal. Bronze Age settlements from NW Portugal are characterized by the presence archaeological structures such as storage pits, postholes and trenches. These subtle structures have a very low dielectric contrast, making them quite difficult to detect in GPR surveys. In the case of Pego Site, previous investigations using conventional archaeological techniques, during a rescue excavation, partially revealed a residential area, a necropolis, and a stockade foundation trench that encircle the whole settlement. Different GPR prospection approaches were performed using GSSI Sir 3000 System, with 400 MHz antennae, with the objective of identify and define the borders between the different areas of human occupation inside the settlement. For the GPR survey, a grid-based approach with closely spaced parallels transects was defined, covering different areas inside the site. A first survey was conducted with a pseudo-3D methodology, with 50 cm profile separation, followed by a second survey with a dense data acquisition methodology, with 10 cm profile separation. Processed two-dimensional GPR profiles and constructed amplituded-slice maps were produced and analysed. Wave velocities were determined by reflected wave methods and by Hyperbola-Fitting method. The background analysis of the archaeological and geological features of the site, integrated with the preliminary interpretation of GPR data (profiles and amplitude slice-maps) suggest the presence of flat graves, in the west part of the site, and storage pits, post holes and some small trenches, in the centre and north area of the settlement. This interpretation indicates that the settlement is individualized in two different areas, a necropolis and a residential area, such as the first archaeological study

  5. Armorican arrowhead biographies: Production and function of an Early Bronze Age prestige good from Brittany (France

    Directory of Open Access Journals (Sweden)

    Clément Nicolas

    2014-09-01

    Full Text Available Brittany can pride itself on the Armorican arrowheads found in Early Bronze Age graves (2150-1700 BC. In the present state of knowledge, these are the only specialized craft products in knapped flint produced in this region at the western edge of continental Europe. Admired since the 19th century, these flint arrowheads have never really been studied. Due to the wealth of graves and grave-goods, a relatively precise study can be undertaken of the development of these craft products, despite the low number of reliable radiocarbon dates.These arrowheads are characterized by a well-defined type (pointed tang and oblique barbs most often combined with ogival form. Raw materials show the selection of a high quality yellow translucent flint, of which the origin has to be sought at more than 400 kilometers (Lower Turonian flint from Cher Valley. From a technical point of view, Armorican arrowheads reveal a great mastery of retouch by pressure-flaking. This skill is written in stone by the perfection of forms, the extreme thinness (until 2,5 mm thick and very long barbs (until 25 mm long. Such work could not have been done without the use of copper, even bronze, awls. Moreover, some marks may testify to the implication of these tools. On 549 arrowheads that have reached to us, none of them presents diagnostical impact features. However, use-wear analysis indicates that most of them were hafted (adhesive traces, bright spots, blunt edges. These facts suggest that they are less functional arrowheads than objects for the show. In the graves, Armorican arrowheads are frequently set down carefully in wooden boxes taking the shaft off.The Armorican arrowheads with their exotic raw materials, their high-degree of technicality, and their absence of use, have all features of a prestige good. They have been discovered by dozens in few graves under barrows with very rich funeral items (bronze daggers decorated with golden pins, precious bracers, silver beakers

  6. Crystallographic conditions for the initiation of cavitation erosion in CuMn11Al11 bronze

    Directory of Open Access Journals (Sweden)

    D. Zasada

    2008-09-01

    Full Text Available Purpose: The basic aim of this paper is to examine and present specific destruction processes connected with cavitation erosion of multi-component Cu-Mn-Al bronzes. In technical operational conditions these processes are ‘masked’ by the effects of electrochemical corrosion phenomena. However, these destructive processes may significantly accelerate the destruction of flow devices and marine propulsion systems. The essential phenomena occurring during these processes are incubation and propagation of brittle cracks in the planes of cleavage planes of the ordered phase β (Cu3Mn2Al that occurs in the examined group of alloys. Additional purpose is the assessment of possible applications of alloys with single-phase structure of intermetallic phases as model materials for research into erosion-cavitation resistance.Design/methodology/approach: This work presents research results concerning erosion cavitation resistance of a model alloy examined at a cavitation jet stand. The destructed areas were examined by gravimetric methods and those using scanning microscopy combined with computer image analysis. As the test materials used were single phase model alloys with the composition simulating selected phase components of Cu-Mn-Al bronzes, it was possible to examine erosion cavitation phenomena in the conditions of minimized effect of electrochemical phenomena.Findings: It has been found that at the initial period of destruction of the phase β in multi-component Mn-Al bronzes the prevailing form of destruction was a classical attack along grain boundaries, starting from the grain boundary junctions while in cases where the Cu3Mn2Al superstructure was present, the major mechanism of the incubation of erosion cavitation damage in the phase β is brittle cracking along cleavage planes {001} oriented at 45° angle to the exposed surface.Research limitations/implications: An essential problem is the verification of the results obtained using the

  7. Earthquake and the Catastrophic End of the Late Bronze Age in the Eastern Mediterranean

    Science.gov (United States)

    Nur, A.

    2009-04-01

    The reasons for the catastrophic and wide spread political as well as physical collapse in the Aegean and Eastern Mediterranean areas that define the end of the Bronze age ca. 1225 BC to 1175 BC remain a major enigma. It has been attributed by historian to attacks by outsiders with the most favored group being the (enigmatic) so-called sea people. Unfortunately there is no real evidence for this. However combined geological, geophysical and archaeological evidence suggests that earthquakes may have played a key role in this extraordinary collapse during the late 13th and early 12th centuries . Based on the instrumentally recorded earthquakes occurring in the Aegean and Eastern Mediterranean region during the 20th century, several events that have clear historical information, and the geography of seismically active faults it is obvious that numerous earthquakes of magnitude 6·5 or greater (enough to destroy modern buildings, let alone those of antiquity) occurred here frequently in the past. Furthermore major earthquakes often occur in this region in groups, known as ‘‘sequences'' or ‘‘storms'', in which one large quake is followed days, months, or a few years later by others elsewhere on the plate boundary fault lines. When a map of the areas in the Aegean and Eastern Mediterranean region shaken by 20th century  earthquakes of magnitude 6·5 and greater and with an intensity of VII or greater is overlaid on Robert Drews' map of sites destroyed in these same regions during the so-called ‘‘Catastrophe'' near the end of the Late Bronze Age, it is readily apparent that virtually all of these LBA sites lie within the affected (‘‘high-shaking'') areas. This would suggest that a major ‘‘earthquake storm'' may have occurred in the Late Bronze Age Aegean and Eastern Mediterranean during the years 1225-1175 . This ‘‘storm'' may have interacted with societal, political and economic forces at work in these areas c. 1200  and

  8. Marco legal do Programa Nacional de Alimentação Escolar: uma releitura para alinhar propósitos e prática na aquisição de alimentos

    Directory of Open Access Journals (Sweden)

    Carla Rosane Paz Arruda Teo

    2012-10-01

    Full Text Available Este ensaio pretende discutir a aquisição de alimentos para o Programa Nacional de Alimentação Escolar à luz do seu marco legal vigente, na perspectiva de promover hábitos alimentares saudáveis e culturalmente articulados que contribuam para a promoção das condições de saúde da população escolar brasileira e para o desenvolvimento local. Apresentase análise da legislação em vigor do Programa Nacional de Alimentação Escolar, evidenciando a intencionalidade de influenciar o sistema alimentar brasileiro e o padrão alimentar de sua população a partir da alimentação escolar, destacandose as lacunas que desafiam a efetivação de mudanças substanciais na execução do programa. Partindo dessa análise e com base no elevado e crescente consumo de alimentos ultraprocessados no Brasil, e considerando as desvantagens desses alimentos diante de alimentos pouco ou não processados, desenvolvese proposta para orientar a construção de uma pauta de alimentos que seja consistente com o marco legal vigente do programa e com seus objetivos. Argumentase que a predominância de alimentos pouco ou não processados na alimentação escolar pode ser estratégia para o resgate do patrimônio alimentar saudável e para o fortalecimento do desenvolvimento local se resultar da aproximação com a agricultura familiar.

  9. marco organizacional

    Directory of Open Access Journals (Sweden)

    Juan David Velásquez H.

    2006-01-01

    Full Text Available Ha sido ampliamente reconocida la importancia de la predicción en la toma de decisiones, y se han encontrado evidencias de que uno de los métodos más efectivos es el ajuste de los pronósticos obtenidos a partir de modelos matemáticos usando juicios informados. No obstante, existe una amplia cantidad de factores que pueden afectar la calidad y credibilidad de las predicciones; en este trabajo se examinan aquellos factores relacionados con las políticas organizacionales, y se proponen varias estrategias para su mitigación.

  10. Photoelectrochemical production of atomic hydrogen at tungsten bronze/aqueous solution interface

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, G.; Schiller, R.

    1988-12-01

    The cathodic photoeffect on hydrogenated sodium tungsten bronzes was studied in acid solutions under potentiostatic conditions. Solute effect proved the accompanying chemical reactions in the liquid phase to be brought about by hydrogen atoms. Kinetic analysis of the photocurrent showed that photoproduction and second-order recombination of the charge carriers in the solid are followed by reversible reduction of H/sup +/ at the interface. Finally H-atoms react with solutes like O/sub 2/, NO/sub 3//sup -/, Fe/sup 3+/, Fe(CN)/sub 6//sup 3-/, or tetranitromethane. The kinetics of charge carrier formation and of chemical reactions seem to be only weakly coupled, and the entire process can be described in terms of homogeneous kinetics showing diffusion and migration to be kinetically unimportant.

  11. Structural Analysis and Electrical Property of Tungsten Bronze Prepared by Rare Earth Gaseous Permeation

    Institute of Scientific and Technical Information of China (English)

    李中华; 李昕; 陈刚; 苏铭汉; 韦永德

    2004-01-01

    The cubic sodium tungsten bronzes, NaxWO3(x=0.854 and 0.814)were prepared by rare earths gaseous permeation method. Structural analysis was carried out by Rietveld method from powder X-ray diffraction data. The X-ray diffraction profile calculated with cubic P32 models are in good agreement with the observed X-ray diffraction patterns. There is only a little difference in W-O bond and Na-O bond between Na0.854WO3 and Na0.814WO3. Conductivity measurements indicate that NaxWO3 show anomalous semiconducting behavior and percolation model was used to interpret it.

  12. Influence of precipitate size and morphology on grain refinement in nickel aluminium bronze

    Science.gov (United States)

    Barr, C. J.; Xia, K.

    2015-08-01

    Nickel aluminium bronze (NAB) was subjected to equal channel angular pressing (ECAP) using routes BA and C at 400°C to investigate the effect of precipitate size and morphology on grain refinement in low stacking fault energy alloys. Both routes produced dynamically recrystallised grains of ∼550 nm in size although only route BA was able to create a uniform distribution of the refined grains. The large unrefined regions in NAB processed via route C was thought to arise from its inability to redistribute the various precipitate phases, as recrystallisation was enhanced around the coarse κII rosettes and refined κIII lamellae but reduced in the areas containing fine κIV precipitates.

  13. Paysages funéraires de l’âge du Bronze

    OpenAIRE

    Gomez de  Soto, José

    2015-01-01

    Du 15 au 18 octobre 2008 s’est tenu au musée de Herne en Westphalie un colloque international intitulé « Gräberlandschaften der Bronzezeit. Paysages funéraires de l’âge du Bronze ». Cette manifestation s’insère dans une succession de colloques bi-annuels inaugurée par celui sur le RSFO tenu à Nemours en 1986. Les actes, qui viennent de paraître, réunissent trente-sept contributions, rédigées en allemand, en français ou en anglais. Les résumés, donnés dans les trois langues, permettront à ceux...

  14. Silvery hair with bronze-tan in a child: A case of Elejalde disease

    Directory of Open Access Journals (Sweden)

    Inamadar Arun

    2007-01-01

    Full Text Available A 5-year-old boy was admitted for severe neurological impairment including hypotonia and loss of consciousness without preceding febrile illness. On examination, he had silver colored hair and bronze-tan over photo-exposed body parts. He was born of consanguineous parents and three of his elder siblings, who died in early childhood, had similar colored hair. Complete blood count and serum immunoglobulin levels were within normal limits. Peripheral blood smear did not show any cytoplasmic granules in neutrophils. Cerebro-spinal fluid examination did not reveal any abnormality. Light microscopic examination of the hair revealed irregular clumping of the melanin throughout the shafts. The patient died on the second day following admission. A clinical diagnosis of Elejalde disease was made. The clinical and genetic overlapping of the three silvery-hair syndromes has been discussed.

  15. A 3-phase model for mixed columnar-equiaxed solidification in DC casting of bronze

    International Nuclear Information System (INIS)

    A three-phase Eulerian approach is used to model the columnar-to-equiaxed transition (CET) during solidification in DC casting of technical bronze. The three phases are the melt, the solidifying columnar dendrites and the equiaxed grains. They are considered as spatially interpenetrating and interacting continua by solving the conservation equations of mass, momentum, species and enthalpy for all three phases. The so defined solidification model is applied to a binary CuSn6 DC casting process as a benchmark to demonstrate the model potentials. Two cases are studied: one considering only feeding flow and one including both feeding flow and equiaxed sedimentation. The simulated results of mixed columnar and equiaxed solidification are presented and discussed including the occurrence of CET, phase distribution, feeding flow, equiaxed sedimentation and their influence on macrosegregation.

  16. Corrosion atmosphérique des bronzes et Spectroscopie Mössbauer.

    OpenAIRE

    Sougrati, Moulay Tahar

    2008-01-01

    Afin d'améliorer la compréhension de la corrosion atmosphérique des bronzes, nous avons mis en oeuvre : - La caractérisation des composés d'étain, susceptibles d'être formés en corrosion atmosphérique, par une approche multi-analytique, la spectroscopie Mössbauer joue un rôle central (analyse sélective et quantitative). Les paramètres hyperfins et les facteurs Lamb-Mössbauer de plusieurs oxydes, sulfates et chlorures d'étain ont été déterminés. Les facteurs f sont dispersés et dépendants de t...

  17. Influence of heat treatment on tribological behaviors of novel wrought aluminum bronze

    Institute of Scientific and Technical Information of China (English)

    张卫文; 倪东惠; 夏伟; 邱诚; 陈维平

    2002-01-01

    Influence of heat treatment on mechanica l properties and tribologica l behaviors of Ti and B modified wrought aluminum bronze were studied. The res ults show that different strength and plasticity combination of the alloy after solu tion treatment can be obtained by adjusting the ageing temperature. When aged at 45 0 ℃, the tensile strength σb, yield strength σ0.2, elongatio n δ and hardness of the alloy are 1 050 MPa, 780 MPa, 4.5%, HB282, respectively. When aged at 650 ℃, those of the alloy are 905 MPa, 600 MPa, 12%, HB232, respectively. Under boundary l ubri cation condition with pressure above 22.2 MPa, alloy with low temperature agei ng has the best wear property. However, under the condition involving impact or sh ock loading, alloy with high temperature ageing is preferable. If the load is no t heavy, the alloy under extrusion state is favorable for wear-resisting parts.

  18. Troben un palau i un ric aixovar de l’Edat del Bronze a La Almoloya

    OpenAIRE

    Lull, Vicente; Rihuete Herrada, Cristina; Micó Pérez, Rafael; Risch, Robert

    2014-01-01

    Un equip d'arqueòlegs de la UAB ha tret a la llum el ric patrimoni històric i arqueològic de La Almoloya, un jaciment de la Regió de Múrcia, que va ser bressol de la societat d’El Argar que va habitar el sud-est de la península Ibèrica durant l'Edat del Bronze. Les troballes realitzades indiquen que La Almoloya era un centre de concentració política i riquesa de primer ordre dins del territori polític d’El Argar. Una de les peces més valuoses és una diadema de plata, l'única de la seva època ...

  19. Electronic Structures of Purple Bronze KMo6O17 Studied by X-Ray Photoemission Spectra

    Science.gov (United States)

    Qin, Xiaokui; Wei, Junyin; Shi, Jing; Tian, Mingliang; Chen, Hong; Tian, Decheng

    X-ray photoemission spectroscopy study has been performed for the purple bronze KMo6O17. The structures of conduction band and valence band are analogous to the results of ultraviolet photoemission spectra and are also consistent with the model of Travaglini et al., but the gap between conduction and valence band is insignificant. The shape of asymmetric and broadening line of O-1s is due to unresolved contributions from the many inequivalent oxygen sites in this crystal structure. Mo 3d core-level spectrum reveals that there are two kinds of valence states of Molybdenum (Mo+5 and Mo+6). The calculated average valence state is about +5.6, which is consistent with the expectation value from the composition of this material. The tail of Mo-3d spectrum toward higher binding energy is the consequence of the excitation of electron-hole pairs with singularity index of 0.21.

  20. Studies of solids at low temperatures. Final scientific report. [Fluoro-tungsten bronzes

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, W.G.

    1970-10-01

    One of the primary objectives of this research has been to investigate the magnetic properties of materials which are likely to exhibit unusual magnetic transitions which may prove to be useful for microwave or switching devices. Experimental techniques used in this research included nuclear magnetic resonance, magnetic susceptibility measurements, optical spectroscopy, and electron spin resonance. A second goal was to develop relationships between magnetic properties and chemical bonding so that eventually magnetic properties could be predicted from the structure of a compound. Another objective of this research was to investigate the possibility of superconductivity in the fluoro-tungsten bronzes. Forty-two of these compounds were synthesized and all were found to have superconducting transition temperatures between one and one half degrees and five degrees kelvin. Relationships between the critical fields and the transition temperature and the composition have been established.

  1. Performance evaluation of grid-enabled registration algorithms using bronze-standards

    CERN Document Server

    Glatard, T; Montagnat, J

    2006-01-01

    Evaluating registration algorithms is difficult due to the lack of gold standard in most clinical procedures. The bronze standard is a real-data based statistical method providing an alternative registration reference through a computationally intensive image database registration procedure. We propose in this paper an efficient implementation of this method through a grid-interfaced workflow enactor enabling the concurrent processing of hundreds of image registrations in a couple of hours only. The performances of two different grid infrastructures were compared. We computed the accuracy of 4 different rigid registration algorithms on longitudinal MRI images of brain tumors. Results showed an average subvoxel accuracy of 0.4 mm and 0.15 degrees in rotation.

  2. Qualitative and quantitative laser-induced breakdown spectroscopy of bronze objects

    Science.gov (United States)

    Tankova, V.; Blagoev, K.; Grozeva, M.; Malcheva, G.; Penkova, P.

    2016-03-01

    Laser-induced breakdown spectroscopy (LIBS) is an analytical technique for qualitative and quantitative elemental analysis of solids, liquids and gases. In this work, the method was applied for investigation of archaeological bronze objects. The analytical information obtained by LIBS was used for qualitative determination of the elements in the material used for manufacturing of the objects under study. Quantitative chemical analysis was also performed after generating calibration curves with standard samples of similar matrix composition. Quantitative estimation of the elemental concentration of the bulk of the samples was performed, together with investigation of the surface layer of the objects. The results of the quantitative analyses gave indications about the manufacturing process of the investigated objects.

  3. Performance and Carcass characteristics of broad breasted bronze toms fed radappertized Diet

    International Nuclear Information System (INIS)

    The effect of irradiated complete diets at dose level of 25 KGy was studied in broad breasted bronze tome evaluating their growing performances as well as characteristics of the carcasses. Two experimental groups received irradiated and non irradiated diets for 18 weeks (from the 5th to the 23rd week of age). Four toms per treatment at the age of 23 weeks were slaughtered and the carcass was dissected. Radappertized diets improved body weight gain, feed consumption and feed conversion and reduced mortality rate. No significant differences were observed between toms fed processed and non processed diets on carcasses components, while the gizzard weight was greater for those fed the processed diets. Dressing and drawn weights in toms fed processed diets were 3% higher than in those fed non processed diets. The results suggest that sterilization of turkeys feed may have a beneficial effect on the body weight and deed conversion of turkeys consuming these diets without harmful effect on the bird

  4. Aromatic quinoxaline as corrosion inhibitor for bronze in aqueous chloride solution

    Indian Academy of Sciences (India)

    N Saoudi; A Bellaouchou; A Guenbour; A Ben Bachir; E M Essassi; M El Achouri

    2010-06-01

    A new corrosion inhibitor, viz. 3-ethyl-6-méthyl-quinoxalin-2-one, 1-benzyl-6-methyl-quinoxalin- 2-one, 2-benzyloxy-3,6-dimethyl-quinoxaline, 1-benzyl-3-methyl-quinoxalin-2-one, were synthesized in the laboratory. Their influence on the inhibition on corrosion of bronze in aqueous chloride solution (3% NaCl) was studied by electrochemical polarization methods and weight-loss measurements. The impact of temperature on the effectiveness of the substances mentioned above has been determined between 20 and 60°C. The results showed that the corrosion resistance was greatly enhanced in the presence of inhibitor and that the effectiveness depends on some physicochemical properties of the molecule, related to its functional groups. These compounds act through the formation of a protective film on the surface of the alloy.

  5. Combining X-ray based methods to study the protohistoric bronze technology in Western Iberia

    Energy Technology Data Exchange (ETDEWEB)

    Valério, P., E-mail: pvalerio@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS (Portugal); Silva, R.J.C., E-mail: rjcs@fct.unl.pt [CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Monte de Caparica (Portugal); Soares, A.M.M., E-mail: amsoares@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS (Portugal); Araújo, M.F., E-mail: faraujo@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS (Portugal); Gonçalves, A.P., E-mail: apg@ctn.ist.utl.pt [Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Campus Tecnológico e Nuclear, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS (Portugal); Soares, R.M., E-mail: ruigusmao@hotmail.com [UNIARQ, Centro de Arqueologia da Universidade de Lisboa, Faculdade de Letras, Alameda da Universidade, 1600-214 Lisboa (Portugal)

    2015-09-01

    The Phoenician arrival at Iberian coastal regions had an actual influence on indigenous technology. A collection of coeval metallurgical remains and artefacts was studied by EDXRF, micro-EDXRF, SEM–EDS and XRD, to identify certain features of the production and utilisation of metal in protohistoric Western Iberia. The composition of artefacts indicates a prevalence of Cu–Sn alloys with low content of impurities (Pb, As, Sb and Fe) during Late Bronze and Early Iron Ages, while the composition of slags points to a smaller loss of copper in Phoenician smelting operations. Moreover, the amount of iron impurities in metal proved to be a helpful discriminator between indigenous and Phoenician-based metallurgies, showing that later alloys have higher amounts of iron. Besides, the indigenous alloys have higher tin contents that can probably be explained by the easier access to metal sources of local communities.

  6. Combining X-ray based methods to study the protohistoric bronze technology in Western Iberia

    International Nuclear Information System (INIS)

    The Phoenician arrival at Iberian coastal regions had an actual influence on indigenous technology. A collection of coeval metallurgical remains and artefacts was studied by EDXRF, micro-EDXRF, SEM–EDS and XRD, to identify certain features of the production and utilisation of metal in protohistoric Western Iberia. The composition of artefacts indicates a prevalence of Cu–Sn alloys with low content of impurities (Pb, As, Sb and Fe) during Late Bronze and Early Iron Ages, while the composition of slags points to a smaller loss of copper in Phoenician smelting operations. Moreover, the amount of iron impurities in metal proved to be a helpful discriminator between indigenous and Phoenician-based metallurgies, showing that later alloys have higher amounts of iron. Besides, the indigenous alloys have higher tin contents that can probably be explained by the easier access to metal sources of local communities

  7. A mineralogical study of Late Bronze Age ceramics from Palatca (Transylvania, Romania

    Directory of Open Access Journals (Sweden)

    Lucretia Ghergari

    2012-01-01

    Full Text Available Our paper studies the mineralogical and petrographical characteristics of 28 ceramic fragments that were excavated in the village of Palatca, Transylvania (Romania. Optical microscopy, X-Ray powder diffraction (XRD, scanning electron microscopy (SEM, grain size analyses, and porosity measurements were used to investigate the samples. Our objective was to describe or reconstruct the corresponding products and to elucidate the manufacturing process, the firing techniques, and the transformation pathways. Based on our results, we conclude that the Late Bronze Age ceramics (1600-1300 BC were produced from clay and temper material such as river sand and ceramoclasts. It has been modeled by hand and fired between 800 and 950°C. For most samples, we can narrow the temperature range to 850-900°C. We interpret the data further from a geoarchaeological point of view with respect to the historical evolution of the local culture.

  8. Towards mineralogical and geochemical reference groups for some Bronze Age ceramics 
from Transylvania (Romania

    Directory of Open Access Journals (Sweden)

    Volker Hoeck

    2009-09-01

    Full Text Available Based on their chemical composition ceramic shards from three Bronze Age sites in Transylvania, i.e., Copăceni, Derşida and Palatca respectively, were distinguished by major, trace, and RE elements. Within the Copăceni samples, two subgroups (A and B showing different chemistry and mineralogy were additionally separated out. The link between chemistry and mineralogy showed clearly the important contribution of the temper to the overall chemistry of the ceramic shards. In turn, the chemistry facilitated the provenance study of the raw materials, which were collected in the vicinity of the sites. In combination with the mineralogy of the ceramics, the chemical analyses can serve as a basis for a geochemical reference set used by further studies.

  9. The inhibition effect and mechanism of L-cysteine on the corrosion of bronze covered with a CuCl patina

    International Nuclear Information System (INIS)

    Highlights: • CuCl patina was synthesized on bronze electrodes with electrochemical method. • L-cysteine was used as a green inhibitor for bronze covered with CuCl patina. • The inhibition efficiency reached above 90%. • The inhibition mechanism of L-cysteine on CuCl patina was investigated. - Abstract: CuCl patina was synthesized on bronze electrodes with electrochemical method. The inhibition effect and mechanism of L-cysteine (Cys) on bronze covered with CuCl patina have been studied with electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) techniques. The EIS results show that Cys stabilized the CuCl patina to a great extent. The hydrolysis reaction of CuCl was inhibited effectively and an inhibition efficiency of over 90% was achieved. The XPS analyses indicate that the chemisorption of Cys molecules on CuCl surface occurred through sulfur atom in thiol and nitrogen atom in amino group

  10. Late Bronze Age in Alcáçova de Santarém (Portugal

    Directory of Open Access Journals (Sweden)

    Arruda, Ana Margarida

    2015-06-01

    Full Text Available The field work that took place in the restaurant area in Jardim das Portas do Sol (Alcáçova de Santarém recovered well-preserved archaeological layers dated to the Late Bronze Age, lying directly underneath the Iron Age phase. The excavation made it possible to collect an important set of ceramics that incorporate printed and incised decoration, which can be easily decoration related to the Cogotas 1 cultural background. Burnished decorations, with grooves on the inner surface and outer strips, are less common. The formal repertoire does not deviate from what is known about the Late Bronze Age in central and southern Iberian Peninsula. The data allow us to propose a chronology centered in the early 1st millennium BCE for this occupation.Durante los trabajos de campo, realizados en el área del restaurante del Jardim das Portas do Sol, se documentaron, por primera vez en Alcáçova de Santarém, niveles conservados del final de la Edad del Bronce, inmediatamente infrapuestos a los de la Edad del Hierro. Su excavación permitió recoger un conjunto de materiales cerámicos que incorpora varios fragmentos decorados por impresión e incisión, que pueden ser fácilmente relacionados con el universo cultural de Cogotas 1. Las decoraciones bruñidas con surcos en la superficie interna y con franjas al exterior son mucho menos frecuentes. El repertorio formal no difiere del conocido para el Bronce Final del centro y sur de la Península Ibérica. Los datos permiten proponer una cronologia del inicio del 1 milenio a.n.e. (siglo IX para esta ocupación.

  11. Bronze age cosmology and rock art images. Solar ships, deer and charts

    Science.gov (United States)

    Dimitriadis, G.

    Bronze Age societies were technologically complex. The impressive production of metal artefacts embodies clearly their astronomical culture and cosmological viewpoint. Same ascertainment is valid also for rock art. In fact, around the European landscape were discovered several cliffs engraved with solar ships, deer and charts. How one could be interpret them? Which is the hidden mentality? From the end of 3rd millennium-early 2nd millennium B. C. deep technological transformations are made by metals. New inventions such metal extraction for weapon production, horse pulling chariot used for war and the bull pulling one used for trade may shorten the culture and material distances between Central Europe and South Mediterranean area. Indeed, taphonomic studies indicate a specific modification of the human body mortuary traditional disposition (orientated to significant astronomical targets) below a substantial transformation of mortuary apparatus with spot evidence of weapons (halberds, swords, knifes) and ornaments (double spiral, lunar shape pectorals). The famous Trundhold Solar chart, the 2nd millennium terracotta chart form Dupljaja, the solar boats petroglyph in Bohusland and the horse rider carved on Philippi's cliffs were conceived by the same mentality: communion with the divinity. Culture expressions as communicate manifestation attested in rock art were produced by the same mentality presented in Bronze Age art-crafts such as, 1. Culture epidemiologic patterns dispersion took place through out iconographic motives, and, 2. Animals can play a double face function inside an analogical-mythological system: a. animal-reflex; b. animal-agent. The question is: Could such petroglyphs help us to "read" archaeoastronomical properly in an archaeological site?

  12. Comparison of LIBS and {mu}-XRF measurements on bronze alloys for monitoring plasma effects

    Energy Technology Data Exchange (ETDEWEB)

    Alberghina, M F; Barraco, R; Brai, M; Schillaci, T; Tranchina, L, E-mail: tschillaci@unipa.it [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed. 18, 90128 Palermo (Italy)

    2011-01-01

    The laser-induced breakdown spectroscopy (LIBS) technique is often used as atomic spectroscopic technique for elemental analysis of materials. However, it presents some drawbacks that make an accurate quantitative analysis difficult. Since the plasma properties, such as spatial inhomogeneity and plume stoichiometry strongly depend on the experimental conditions, the measurements are less reproducible. In order to evaluate the measurement fluctuations, we propose to use the more established micro X-Ray fluorescence ({mu}-XRF) technique for validating LIBS data. In particular, the quantitative data, obtained by varying the laser fluence, the shot numbers and the temporal acquisition parameters, were compared with those obtained by {mu}-XRF on laboratory made samples of binary, ternary and quaternary bronze alloys. For LIBS measurements a mobile double pulse laser instrument equipped with an high resolution Echelle type monochromator coupled to an intensified CCD camera was used. {mu}-XRF analyses were performed with a portable instrument that uses a micro collimated X-Ray beam and it is equipped with an high resolution detector. The LIBS results show a strong dependence both on the instrumental set up and the chemical-physical properties of the sample. With our findings we could identify the most suitable parameters to be used in the investigation of the different bronze alloys. The possibility to carry out a quantitative analysis by using the LIBS technique was checked through the comparison with related {mu}-XRF data. In particular in this paper we identified a set of reliable LIBS parameters for the quantitative analysis of copper, tin and zinc. Further analyses will be necessary to reach this goal also for the minor constituents as lead.

  13. Archaeological fieldwork in the Bronze Age site of Cerro de la Encina (Monachil, Granada

    Directory of Open Access Journals (Sweden)

    Aranda Jiménez, Gonzalo

    2005-06-01

    Full Text Available New archaeological fieldwork has been carried out from November 2003 to May 2004 in the Bronze Age site of Cerro de la Encina, due to the interest of the regional government of Andalusia in displaying the settlement for visitors. The aim of this fieldwork has been the systematic excavation of a large settlement area partially known thanks to the excavations developed at the beginning of 1980s. A first toccupation period belonging to the Argaric Culture has been documented, highlighting specially the funerary ritual characterized by individual inhumations located below dwellings. After a gap in the occupation of the settlement a new social group belonging to the Late Bronze Age Culture of Southeast of Spain inhabits the Cerro de la Encina.

    El interés de la Consejería de Cultura de la Junta de Andalucía por la musealización del yacimiento del Cerro de la Encina ha motivado el desarrollo de nuevas investigaciones arqueológicas cuya primera fase se ha desarrollado entre Noviembre de 2003 y Mayo de 2004. Los trabajos han consistido en la excavación sistemática de un área de poblado de grandes dimensiones parcialmente conocida por las investigaciones realizadas a principios de los años 80. Los resultados han sido del máximo interés documentándose un primer momento de ocupación perteneciente a la Cultura de El Argar en el que destaca su espectacular registro funerario integrado dentro de las áreas de habitación. Tras un periodo de abandono del yacimiento se produce una nueva ocupación correspondiente a una comunidad del Bronce Final del Sureste.

  14. Biological affinities and adaptations of Bronze Age Bactrians: IV. A craniometric investigation of Bactrian origins.

    Science.gov (United States)

    Hemphill, B E

    1999-02-01

    Discovery of a previously unknown Bronze Age civilization (Oxus civilization) centered on the oases of Central Asia revealed the presence of large, preplanned urban centers immediately above sterile soil. Given the absence of local antecedents, the sudden appearance and proliferation of these Oxus civilization urban centers in the oases of Bactria and Margiana immediately raised the issue of where the inhabitants of these urban centers came from. Three hypotheses have been offered by archaeologists to account for the origins of Oxus civilization populations. These include the early influence model, the late colonization model, and the trichotomy model. Eleven craniometric variables from 12 Aeneolithic and Bronze Age samples, encompassing 657 adults from Central Asia, Iran, and the Indus Valley, are compared to test which if any of these hypotheses are supported by the pattern of phenetic affinities possessed by the Oxus civilization inhabitants of the north Bactrian oasis. Craniometric differences between samples are compared with Mahalanobis generalized distance (d2), and patterns of phenetic affinity are assessed with two types of cluster analysis (WPGMA, neighbor-joining method), multidimensional scaling, and principal coordinates analysis. Results of this analysis provide no support for either the late colonization model or the trichotomy model but do offer some support for the early influence model. Nevertheless, it is clear that the early influence model fails to account for a shift in interregional contacts, perhaps from western China to the north around 2000 BC, that appears to have played a major role in the origins of the Oxus civilization inhabitants of the north Bactrian oasis. PMID:9988380

  15. Sistema auxiliar para colocar el marco estereotáctico en el cráneo

    Directory of Open Access Journals (Sweden)

    J Jesús Nieto-Miranda

    2012-08-01

    Full Text Available Titulo inglés:  Auxiliary system for positioning the stereotactic frame to the skull Resumen: En neurocirugía funcional y radioneurocirugía estereotáctica, la fijación de un marco en el cráneo, permite el establecimiento de un sistema tridimensional de coordenadas, para localizar y definir con precisión los objetivos en el cerebro. El montaje se basa en la experiencia y la percepción visual del médico, pero los resultados son subjetivos y la calibración de las coordenadas del marco con respecto al cráneo no siempre es la óptima para el desarrollo del procedimiento quirúrgico. Este estudio evalúa la eficacia y la funcionalidad de un sistema auxiliar diseñado para colocar el marco estereotáctico en el cráneo. La evaluación se realiza por medio de un estudio comparativo de dos grupos de 7 pacientes cada uno sometidos a tratamiento de radioneurocirugía. En el primer grupo no es utilizado el sistema, solo en el segundo, se tomaron 165 imágenes (IRM en promedio por cada estudio. El empleo del sistema auxiliar disminuye la variación de la inclinación y la rotación del marco con respecto al cráneo hasta un 64%, la apreciación subjetiva del médico es sustituida por una medición objetiva, obteniéndose certidumbre al posicionar el marco sobre el cráneo. Los resultados muestran que el sistema auxiliar diseñado es eficaz y funcional. Palabras clave: Neurocirugía; radioneurocirugía; marco estereotáctico; técnica estereotáctica. Abstract: In functional neurosurgery and stereotactic radioneurosurgery, the fixation of a frame to the skull allows the establishment of a three-dimensional coordinate system, to locate and precisely defined objectives in the brain. The montage is based on experience and visual perception the doctor, the results obtained and the calibration of the coordinates of the frame with respect to the skull is not always the optimal for developing the surgical procedure. This study evaluates the effectiveness

  16. Uranium series isotopes concentration in sediments at San Marcos and Luis L. Leon reservoirs, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Spatial and temporal distribution of the radioisotopes concentrations were determined in sediments near the surface and core samples extracted from two reservoirs located in an arid region close to Chihuahua City, Mexico. At San Marcos reservoir one core was studied, while from Luis L. Leon reservoir one core from the entrance and another one close to the wall were investigated. 232Th-series, 238U-series, 40K and 137Cs activity concentrations (AC, Bq kg−1) were determined by gamma spectrometry with a high purity Ge detector. 238U and 234U ACs were obtained by liquid scintillation and alpha spectrometry with a surface barrier detector. Dating of core sediments was performed applying CRS method to 210Pb activities. Results were verified by 137Cs AC. Resulting activity concentrations were compared among corresponding surface and core sediments. High 238U-series AC values were found in sediments from San Marcos reservoir, because this site is located close to the Victorino uranium deposit. Low AC values found in Luis L. Leon reservoir suggest that the uranium present in the source of the Sacramento – Chuviscar Rivers is not transported up to the Conchos River. Activity ratios (AR) 234U/238U and 238U/226Ra in sediments have values between 0.9–1.2, showing a behavior close to radioactive equilibrium in the entire basin. 232Th/238U, 228Ra/226Ra ARs are witnesses of the different geological origin of sediments from San Marcos and Luis L. Leon reservoirs

  17. Uranium series isotopes concentration in sediments at San Marcos and Luis L. Leon reservoirs, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Méndez-García, C.; Montero-Cabrera, M. E., E-mail: elena.montero@cimav.edu.mx [Centro de Investigación en Materiales Avanzados, CIMAV, Miguel de Cervantes 120, 31109, Chihuahua, Chihuahua (Mexico); Renteria-Villalobos, M. [Facultad de Zootecnia y Ecología Universidad Autónoma de Chihuahua, Periferico Francisco R. Almada Km 1, 31410, Chihuahua (Mexico); García-Tenorio, R. [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Avda. Reina Mercedes s/n, 41012 Seville (Spain)

    2008-01-01

    Spatial and temporal distribution of the radioisotopes concentrations were determined in sediments near the surface and core samples extracted from two reservoirs located in an arid region close to Chihuahua City, Mexico. At San Marcos reservoir one core was studied, while from Luis L. Leon reservoir one core from the entrance and another one close to the wall were investigated. ²³²Th-series, ²³⁸U-series, ⁴⁰K and ¹³⁷Cs activity concentrations (AC, Bq kg⁻¹) were determined by gamma spectrometry with a high purity Ge detector. ²³⁸U and ²³⁴U ACs were obtained by liquid scintillation and alpha spectrometry with a surface barrier detector. Dating of core sediments was performed applying CRS method to ²¹⁰Pb activities. Results were verified by ¹³⁷Cs AC. Resulting activity concentrations were compared among corresponding surface and core sediments. High ²³⁸U-series AC values were found in sediments from San Marcos reservoir, because this site is located close to the Victorino uranium deposit. Low AC values found in Luis L. Leon reservoir suggest that the uranium present in the source of the Sacramento – Chuviscar Rivers is not transported up to the Conchos River. Activity ratios (AR) ²³⁴U/²³⁸U and ²³⁸U/²²⁶Ra in sediments have values between 0.9–1.2, showing a behavior close to radioactive equilibrium in the entire basin. ²³²Th/²³⁸U, ²²⁸Ra/²²⁶Ra ARs are witnesses of the different geological origin of sediments from San Marcos and Luis L. Leon reservoirs.

  18. Effect of additions of Cr, Mo, W and/or Si on the technological properties of aluminum-iron-nickel bronze

    Directory of Open Access Journals (Sweden)

    B. P. Pisarek

    2011-07-01

    Full Text Available The aim of this study was to investigate the effect of additives of Cr, Mo, W and / or Si CuAl10Fe5Ni5 bronze, cast into sand moulds, the bronze technological properties such as: porosity, volumetric shrinkage Sv, linear shrinkage s and prone hot to cracking. The study relate to the newly developed grades aluminum-iron-nickel bronze, with additions of Cr, Mo, W and/or Si. In order to determine the technological properties of the test castings were made in the form of moulding sand, which made the mould cavities designed patterns. To evaluate the porosity and volumetric shrinkage was used for digital image analysis method. Volumetric shrinkage was determined using developed, the new method, the surface shrinkage Svp designation, and then converting it to the volumetric shrinkage, using prepared relation Sv=f(Djs*Svp. It was found that made the bronze alloy additions to reduce the size of pores surface area of gas and shrinkage in the test bronze. The probability of microporosity with an area of 0.002560÷0.120647 mm2 can be described by gamma distribution. Changing the chemical composition of the grades tested bronze strongly alter the first volumetric shrinkage Sv, and less to change the linear shrinkage s. The increase in gas porosity and shrink in bronze reduces the volumetric shrinkage and linear. The addition of Cr, Mo, W and/or Si to the bronze CuAl10Fe5Ni5 does not change its prone to hot cracking.

  19. Methodology for the Construction of a Rule-Based Knowledge Base Enabling the Selection of Appropriate Bronze Heat Treatment Parameters Using Rough Sets

    OpenAIRE

    Górny Z.; Kluska-Nawarecka S.; Wilk-Kołodziejczyk D.; Regulski K.

    2015-01-01

    Decisions regarding appropriate methods for the heat treatment of bronzes affect the final properties obtained in these materials. This study gives an example of the construction of a knowledge base with application of the rough set theory. Using relevant inference mechanisms, knowledge stored in the rule-based database allows the selection of appropriate heat treatment parameters to achieve the required properties of bronze. The paper presents the methodology and the results of exploratory r...

  20. Combatentes do gueto, guerreiros da periferia

    Directory of Open Access Journals (Sweden)

    Mônica Rebecca Ferrari Nunes

    2013-01-01

    Full Text Available Combatente do gueto, guerreiro da periferia, militante da causa (... Combatente do gueto é o nome de uma rua atrás do Palácio do Governo (...” conta Jairo, taxista, a propósito de sua inspiração poética, durante as filmagens de Povo lindo, povo inteligente – O Sarau da Cooperifa, documentário dirigido por Sérgio Gagliardi e Maurício Falcão, produzido, em 2008, pela DGT Filmes. O filme narra a história e os bastidores do sarau que acontece na zona sul da cidade de São Paulo, em Campo Limpo, no bar do Zé Batidão. “A periferia não tem museu, não tem teatro nem cinema, o único espaço público que tem é o bar”, explica Sérgio Vaz, um dos idealizadores do movimento que contempla na produção poética, da periferia para a periferia, a força da contestação social. A cultura como arena para a luta entre os signos monossêmicos e a pluralidade sígnica proposta pelo artista que faz da palavra ruído incômodo. O sarau da Cooperifa, o sarau do Binho também já foram objetos de estudos acadêmicos, como a tese As redes de escritura nas periferias de São Paulo, de Marco Antônio Bin, defendida no Programa de Ciências Sociais da PUCSP, em maio de 2009

  1. Las Inteligencias Múltiples como marco para atender a los alumnos con adaptaciones curriculares no significativas

    OpenAIRE

    Martí-Saumell, Núria

    2012-01-01

    Nuestra investigación se centra en estudiar las metodologías educativas que facilitan la atención a la diversidad desde la perspectiva de la Teoría de las Inteligencias Múltiples y con una orientación teórico-práctica. El objetivo de nuestro estudio será analizar y seleccionar aquellas metodologías educativas que facilitan la atención a la diversidad dentro del aula, así como analizar el marco que ofrece la Teoría de las Inteligencias Múltiples para atender a la diversidad. A partir de estos ...

  2. LA RECOGIDA DE BASURA EN MEGA-CIUDADES: En el marco de la sostenibilidad

    OpenAIRE

    Fabian Tron

    2010-01-01

    La comprensión de las sociedades urbanas complejas sólo es posible cuando se estudia tanto el sector formal como el informal que las conforma. Para explicar ambos modelos, el rubro de los Residuos surge como una de las herramientas más competentes, capaz de distinguir entre ellos, incluso cuando la demanda de la sociedad supera su marco legislativo. Un cambio de enfoque en el que se defi ne a los residuos sólidos en función a su potencial como recurso, contextualiza realidades muy divergentes...

  3. Oportunidades para el sector eléctrico colombiano dentro del marco del protocolo de Kyoto

    OpenAIRE

    Correa Castrillón, Jairo Andrés

    2008-01-01

    La preocupación mundial por el Cambio Climático Global es creciente debido a los Gases de Efecto Invernadero (GEI), la Convención Marco de Naciones Unidas sobre Cambio Climático (UNFCCC) ha motivado en 1997 el Protocolo de Kyoto (PK) a tomar medidas correctivas para reducir GEI en no menos del 5.2% respecto a los niveles de las de 1990. Para reducir los costos de transacción y las cargas económicas de estos países, se han diseñado diferentes mecanismos: Comercio de Emisiones (CE), Implementac...

  4. Algunos marcos referenciales en la evaluación del desempeño docente

    OpenAIRE

    Vaillant, Denise

    2008-01-01

    El siguiente artículo tiene como objetivo profundizar en marcos referenciales que podrían ser inspiradores para la evaluación del desempeño docente en América latina. Comenzamos por una breve conceptualización de las nociones de “desempeño docente” y de “evaluación docente” y su significado actual. Hoy hay bastante consenso en que la evaluación no es una herramienta burocrática sino un instrumento técnico para el desarrollo profesional docente en general. En un segundo momento, se presenta un...

  5. Tema, estructura y marco narrativo en "Luz de Agosto" de William Faulkner

    OpenAIRE

    Herrero Villapalos, Rosa

    2004-01-01

    Este trabajo tiene como objeto el estudio del tema, la estructura y el marco narrativo en Luz de Agosto de William Faulkner a través de sus personajes. Aunque son Christmas, Lena y Hightower los tres personajes principales en los que se concentra la historia, es Joe Christmas el verdadero motor que hace fluir el relato, él es el hilo en donde se van engarzando las diferentes piezas de historia personaje. Por otra parte, Faulkner utiliza a Lena y su itinerario -de Alabama a Tennesse- como marc...

  6. Interacción universidad y entorno: marco para el emprendimiento

    OpenAIRE

    Pedro Emilio Sanabria-Rangel; María Eugenia Morales-Rubiano; Carolina Ortiz-Riaga

    2015-01-01

    El documento desarrolla el tema de la relación universidad-entorno, especialmente en lo que se refiere a la vinculación con el sector productivo como parte del desarrollo de la función de extensión universitaria. El propósito fundamental es proporcionar un marco de referencia para la creación o justificación de las unidades de emprendimiento universitarias como mecanismo de enlace para el desarrollo de la función extensión desde una de sus aproximaciones: el enfoque empresarial. Como resultad...

  7. Orden económico-social como marco de la transnacionalidad empresarial

    OpenAIRE

    García Echevarría, Santiago

    2006-01-01

    La relación entre el orden económico-social de cada país, no solo en su dimensión normativa sino también en lo que afecta a su cultura económica y social y la fuerza de la necesaria transnacionalidad de la empresa ha constituido durante década la clave del desarrollo de los pueblos. Los procesos de cambio empresarial, que se suceden en el marco de cada país, buscan en la transnacionalidad su futuro y su desarrollo. Antes y ahora la apertura es, sin duda, la referencia empresarial. La inter...

  8. Marco epistemológico de la enfermería

    OpenAIRE

    María Mercedes Durán de Villalobos

    2002-01-01

    El marco epistemológico de la enfermería pretende mostrar, de manera panorámica, la evolución del conocimiento de la enfermería. En primera instancia, se parte de una clarificación del significado de disciplina profesional y de los componentes de la disciplina: perspectiva, dominio, definiciones y conceptos y patrones del conocimiento. A partir de la definición de la disciplina de la enfermería como el estudio del cuidado de la experiencia o vivencia de la salud humana, s...

  9. Introducción a la accesibilidad web (Universidad Nacional Mayor de San Marcos)

    OpenAIRE

    Luján Mora, Sergio

    2011-01-01

    Materiales del curso "Introducción a la accesibilidad web" impartido en la Facultad de Ingeniería de Sistemas e Informática de la Universidad Nacional Mayor de San Marcos (Lima, Perú) en agosto de 2011. Introducción a la accesibilidad web: ¿Qué es la accesibilidad web?; ¿Accesibilidad = usabilidad?; Ayudas técnicas para los discapacitados; ¿Cómo hago que mi sitio web sea accesible?; Legislación en España; Más información. Universidad de Alicante (España) y Universidad Nacional Mayor de San...

  10. Habitabilidad educativa de las escuelas. Marco de referencia para el diseño de indicadores

    OpenAIRE

    Juan Manuel Hernández Vázquez

    2010-01-01

    Este documento propone el concepto de habitabilidad educativa de la escuela (HEE) para contribuir a subsanar la falta de un marco conceptual que apoye la reflexión y el desarrollo de indicadores sobre las condiciones en que operan los servicios educativos en países con extensa pobreza como el nuestro. Comprende la revisión de ocho dimensiones cuya pertinencia se argumenta con base en la revisión de bibliografía internacional sobre las temáticas involucradas. Las ocho dimensiones planteadas in...

  11. Una propuesta de marco de trabajo orientado al dominio del procesamiento transaccional

    OpenAIRE

    Zbucki, Hernán Enrique; Pons, Claudia

    2015-01-01

    La ingeniería de software establece que la construcción de programas debe ser encarado de la misma forma que los ingenieros construyen otros sistemas complejos. Los sistemas de procesamiento transaccional no son la excepción. Para lidiar con algunos de los desafíos de construir estas soluciones, se desarrolló una propuesta de marco de trabajo, que propone la construcción de una base de conceptos comunes, obtenidos del análisis de soluciones preexistentes, y de experiencias del equipo que desa...

  12. ASPECTOS ECONÓMICO-INSTITUCIONALES DEL MARCO REGULATORIO MEXICANO DEL SISTEMA NACIONAL DE INNOVACIÓN

    OpenAIRE

    Martín Puchet Anyul; Pablo Ruiz Nápoles

    2008-01-01

    El marco regulatorio de un sistema de innovación está compuesto por reglas de distinto origen. Dichas reglas hacen posible y condicionan el funcionamiento del sistema. A su vez ellas generan incentivos o restricciones para las acciones de los agentes que integran el sistema. Este artículo se concentra en las reglas surgidas de la legislación mexicana de ciencia y tecnología que cambió entre 1999 y 2003 en concordancia con las reformas económicas. Se caracteriza y describe esa parte del ma...

  13. Governança na internet: um estudo sobre o Marco Civil brasileiro

    OpenAIRE

    Laura Vilela Rodrigues Rezende; Meyrielle Rodrigues de Lima

    2016-01-01

    El trabajo tiene como propósito realizar un estudio sobre la legislación que rige el uso de Internet en Brasil, en el Marco Civil de Internet (Ley 12.965/2014). Se trata de una investigación descriptiva, de naturaleza cua litativa, basada en recopilación bibliográfica y estudio comparativo. Se ex pone inicialmente un breve histórico de Internet en Brasil y su panorama actual. Luego, se presenta el concepto de gobernanza en Internet y los su cesos que marcaron ...

  14. Auditoría de alineamiento con el Marco europeo de interoperabilidad

    OpenAIRE

    Flórez Ruiz, Alberto

    2015-01-01

    En las bases y principios del Esquema Nacional de Interoperabilidad se hacen una serie de manifestaciones que quieren confirmar cómo este Real Decreto tiene presentes las recomendaciones de la Unión Europea recogidas en el Marco Europeo de Interoperabilidad. También se tienen en cuenta otros instrumentos y actuaciones relativas a la interoperabilidad de las Administraciones Públicas Europeas. Dichas recomendaciones se adaptan conforme a la situación tecnológica de las diferentes Administracio...

  15. Evaluación de la sustentabilidad del desarrollo regional. El marco de la agricultura

    OpenAIRE

    Pablo Torres Lima; Luis Rodríguez Sánchez; Óscar Sánchez Jerónimo

    2004-01-01

    La sustentabilidad del desarrollo regional puede evaluarse mediante dife rentes metodologías. Los itinerarios metodológicos para estudiar el papel de la agricultura en el desarrollo sustentable en el ámbito regional proveen de importantes elementos de análisis, tales como las relaciones jerárquicas entre sistemas de producción en el marco de distintos niveles espaciales y temporales. Este trabajo examina los principales enfoques metodológicos e indicadores para evaluar la...

  16. Aprendizaje significativo en el marco del origen de la célula eucariota

    OpenAIRE

    Narváez Palacios, Janeth Patricia

    2012-01-01

    Las ideas desarrolladas por David Ausubel en su teoría de aprendizaje significativo (caracterizado por la interacción entre el nuevo conocimiento y el conocimiento previo) y Marco Antonio Moreira en su propuesta aprendizaje significativo critico (a través del cual el estudiante podrá formar parte de su cultura y, al mismo tiempo, no ser subyugado por ella, por sus ritos, sus mitos y sus ideologías), son aplicadas en el presente trabajo para orientar la enseñanza de la estructura celular, con ...

  17. Marco legal en la protección ambiental de los bosques nativos

    OpenAIRE

    Pohl Schnake, Verónica; Vallejos, Víctor Hugo

    2009-01-01

    Con este trabajo se pretende contribuir al debate en torno a los bosques nativos de nuestro país en el marco de la reciente ley 26.331/07 de "Presupuestos mínimos de protección ambiental de los bosques nativos" y su aún más reciente reglamentación. Se realiza en primer término una breve referencia al encuadre de la legislación ambiental en nuestro país, luego se presentan algunos resultados del Primer Inventario Forestal del año 2001. En una segunda instancia se analizan los principales aspec...

  18. Los entornos personales de aprendizaje en el marco de la educación permanente

    OpenAIRE

    Navas, Elvira

    2013-01-01

    En este trabajo se presenta un estudio documental sobre el surgimiento, evolución y estado actual de la utilización y desarrollo de los Entornos Personales de Aprendizaje (Personal Learning Environment, PLE) en el marco de la Educación Permanente o Aprendizaje para Toda la vida (Lifelong Learning). En primer lugar, se hace una revisión del concepto de Educación Permanente desde la literatura de inicios de siglo XX. A continuación, se procede a estudiar el término PLE, desde sus orígenes hasta...

  19. Violencia en el marco escolar de la enseñanza obligatoria : el profesorado como referencia

    OpenAIRE

    Rodríguez Díaz, Francisco Javier; Gutiérrez, Cristina; Herrero Díez, Francisco Javier; Cuesta Izquierdo, Marcelino; Hernández Granda, Eva; Carbonero, Patricia G.; Jiménez, Asunción

    2002-01-01

    El objetivo de este trabaja es explorar las posibles conductas violentas que aparecen en el aula o en el centro educativo a partir de referencias de profesorado en el marco escotar de la enseñanza obligatoria. De esta manera, a través de una muestra de 69 profesores (40`70 hombres y con una media de 40, 5 años) de la Enseñanza Obligatoria (Primaria y Secundaria), que cubrieron de forma anónima un cuestionario específico para el estudio de la Incidencia del Maltratan entre Iguales (Defensor de...

  20. Les techniques de soudage de la grande statuaire antique en bronze: étude des paramètres thermiques et chimiques contrôlant le soudage par fusion au bronze liquide

    OpenAIRE

    Azéma, Aurélia

    2013-01-01

    Ces travaux s'inscrivent dans une recherche interdisciplinaire qui concerne l'évolution de l'ensemble des techniques de la grande statuaire antique en bronze (de la 2nd moitié du 6 siècle avant J.C. au 5e siècle après J.C.). L'objectif de la thèse est de contribuer à la compréhension du procédé de soudage par fusion au bronze liquide, en mettant en œuvre une double approche : étude de soudures antiques et essais expérimentaux en laboratoire. Les statues à étudier ont été choisies parmi les œu...

  1. A dialética do conflito num mundo fechado. Sentido e limites da teoria política de Carl Schmitt

    OpenAIRE

    Vasques, Rafael Franco

    2015-01-01

    O pensamento e a obra de Carl Schmitt, contínua a constituir um marco importante para vários pensadores contemporâneos. A sua oposição ao retorno da doutrina da guerra justa no ordenamento jurídico internacional, levou-o a tecer severas críticas ao imperialismo americano após o final da I Guerra Mundial. A queda do jus publicum europaeum, no entender, Schmitt, fez antever o aparecimento de uma guerra global, em nome da humanidade e da justiça, incapaz de distinguir militares...

  2. Marco Denevi en la década de los ochenta: Literatura y política Marco Denevi in the decade of eighties: Literature and politics

    Directory of Open Access Journals (Sweden)

    Nicolás Abadie

    2012-01-01

    Full Text Available Con la vuelta de la democracia en Argentina en 1983, comienzan a circular discursos de lo más diversos que tenían como objeto de análisis las causas sociales y políticas que motivaron el último golpe de Estado. Dentro de esta eclosión de objetos literarios, encontramos ficciones que indagan en el modelo de país que se aspiraría a construir y otras que anticipan el futuro de la nación a través de la lectura de los acontecimientos que sucedían en ese momento. Marco Denevi (1922-1998 en esta década incorpora a su particular modo de entender la literatura el rol determinante de la política. Después de haberse iniciado en el relato policial, creado minificciones, escrito piezas teatrales y novelas de gran mimetismo con la clase media argentina, en las obras publicadas en los 80 buscará encontrar las causas del fracaso de esa "anomalía histórica" que se dio en llamar Argentina, sobre todo en la predisposición sicológica y el carácter del porteño rioplatense.With the return of the democracy in Argentina in 1983 they begin to circulate several speeches that took as an object of analysis the social and political reasons that motivated the last military dictatorial government. Inside this great manifestation of literary objects, we find fictions that investigate the model of country who would aspire to construct and others that anticipate the future of the nation across the reading of the events that were happening in this moment. Marco Denevi (1922-1998 in this decade incorporates into his individual way of understanding the literature the determinant role of politics. After writing has begun in the police statement, created minifictions, theatrical pieces and novels of great mimetism with the Argentine middle class, in the works published in the 80 it will seek to find the reasons of the failure of this "historical anomaly" that was given in calling Argentina, especially in the psychological predisposition and the character of the

  3. Ética del discurso: ¿un marco filosófico para la neuroética?

    Directory of Open Access Journals (Sweden)

    Cortina, Adela

    2013-06-01

    Full Text Available Neuroethics requires a framework of philosophical ethics from which to interprete, integrate and criticiseneuroscientific progress in moral field. This article sets out to: 1 Show to what extent this framework is necessary; 2 Tackle the question of the method for constructing this framework; 3 Compile the main tópoi of the neurosciences that the framework has to interpret and integrate; 4 Propose the ethics of discourse as a philosophical framework for neuroethics; 5 Display certain shortcomings of this framework and put forward the dialogical ethics of cordial reason as being more appropriate.La Neuroética necesita un marco de ética filosófica desde el que interpretar, integrar y criticar el progreso neurocientífico en el ámbito moral. Este artículo intenta: 1 Mostrar en qué medida este marco es necesario. 2 Abordar la cuestión del método adecuado para construirlo. 3 Compilar los principales tópoi de las neurociencias que el marco debería interpretar e integrar. 4 Mostrar cómo la ética del discurso puede ser un marco adecuado para la neuroética. 5 Señalar algunas insuficiencias de ese marco y sugerir para superarlas una ética de la razón cordial.

  4. Marco jurídico de la política de telecomunicaciones

    Directory of Open Access Journals (Sweden)

    Carlos Labaure Aliseris

    2014-02-01

    Full Text Available Introducción. Generalidades. Concepto de telecomunicación. Monopolio y competencia. Políticade telecomunicaciones. Noción e instrumentos. Evolución de las políticas de telecomunicaciones. Marco jurídico de las telecomunicaciones. Régimen general. Regímenes específicos.Nos vamos a referir al marco jurídico de la política de telecomunicaciones. Se trata de una regulación sectorial, fijada por el Estado, para una actividad en que actúan sujetos públicos y privados.Dicha regulación ha estado sujeta a cambios, en virtud del avance tecnológico de las últimas décadas en el ámbito de las telecomunicaciones.El avance tecnológico referido ha producido una verdadera revolución en las telecomunicaciones,en cuyo proceso estamos actualmente inmersos.En virtud de ello se han producido importantes modificaciones en el derecho positivo de manera de intentar de acompasar la normativa con el desarrollo tecnológico.En el campo de las telecomunicaciones se han señalado como características de esos cambios, la universalidad, la multiplicidad de medios y la convergencia entre los mismos.

  5. Calibration of the San Marco airglow-solar spectrometer instrument in the extreme ultraviolet

    Science.gov (United States)

    Worden, John; Woods, Thomas N.; Rottman, Gary J.; Schmidtke, Gerhard; Tai, Hongsheng; Doll, Harry G.; Solomon, Stanley C.

    1996-02-01

    The San Marco 5 carried the airglow-solar spectrometer instrument (ASSI). This 18-channel spectrometer measured the solar and terrestrial radiation in the wavelength region between 20 and 700 nm for 9 months in 1988. The ASSI extreme ultraviolet (EUV) channels showed significant sensitivity changes during the mission. The sensitivity changes of the EUV channels are quantified by comparing ASSI solar EUV irradiance measurements to the solar EUV irradiance derived from a solar proxy model. A sensitivity change model is developed that shows that exponential curves can adequately describe the sensitivity changes of the ASSI optics and detectors. The November 10 calibration parameters and the sensitivity change model can be used to derive the EUV terrestrial airglow brightness for the time period of the ASSI mission. Analysis of the solar Lyman-(alpha) irradiance measured by the ASSI, the solar mesospheric explorer (SME), and the upper atmosphere research satellite has led to a revised Lyman-(alpha) irradiance for the San Marco mission. For example, the ASSI November 10, 1988, Lyman-(alpha) measurement is 5.3 X 1011 photons cm-2 s-1 versus the reported SME measurement of 3.35 X 1011 photons cm-2 s-1.

  6. Solar measurements from the Airglow-Solar Spectrometer Instrument (ASSI) on the San Marco 5 satellite

    Science.gov (United States)

    Woods, Thomas N.

    1994-04-01

    The analysis of the solar spectral irradiance from the Airglow-Solar Spectrometer Instrument (ASSI) on the San Marco 5 satellite is the focus for this research grant. A pre-print copy of the paper describing the calibrations of and results from the San Marco ASSI is attached to this report. The calibration of the ASSI included (1) transfer of photometric calibration from a rocket experiment and the Solar Mesosphere Explorer (SME), (2) use of the on-board radioactive calibration sources, (3) validation of the ASSI sensitivity over its field of view, and (4) determining the degradation of the spectrometers. We have determined that the absolute values for the solar irradiance needs adjustment in the current proxy models of the solar UV irradiance, and the amount of solar variability from the proxy models are in reasonable agreement with the ASSI measurements. This research grant also has supported the development of a new solar EUV irradiance proxy model. We expected that the magnetic flux is responsible for most of the heating, via Alfen waves, in the chromosphere, transition region, and corona. From examining time series of solar irradiance data and magnetic fields at different levels, we did indeed find that the chromospheric emissions correlate best with the large magnetic field levels.

  7. Governança na internet: um estudo sobre o Marco Civil brasileiro

    Directory of Open Access Journals (Sweden)

    Laura Vilela Rodrigues Rezende

    2016-01-01

    Full Text Available El trabajo tiene como propósito realizar un estudio sobre la legislación que rige el uso de Internet en Brasil, en el Marco Civil de Internet (Ley 12.965/2014. Se trata de una investigación descriptiva, de naturaleza cua litativa, basada en recopilación bibliográfica y estudio comparativo. Se ex pone inicialmente un breve histórico de Internet en Brasil y su panorama actual. Luego, se presenta el concepto de gobernanza en Internet y los su cesos que marcaron las discusiones acerca de esta temática. Se aborda el Marco Civil de Internet en Brasil, el histórico de su creación y los principios que lo rigen. Se concluye que es un importante instrumento oficial regla mentario para asegurar la libertad y los derechos del usuario. Su concep ción se fundamentó en la participación de la sociedad civil, lo que puede considerarse inédito en lo que se refiere a la creación de leyes reglamenta rias. Se considera que esta sea una ley sofisticada en cuanto a sus directri ces, lo que la vuelve una de las más progresistas del mundo. Pese a todo lo anterior, su trayectoria democrática de creación le otorga un carácter ge neralista y superficial.

  8. Reflexiones sobre el marco conceptual de la contabilidad financiera: El caso de Colombia

    Directory of Open Access Journals (Sweden)

    Ernesto María Sierra González

    2004-01-01

    Full Text Available Con el auge del proceso de normalización contable ha surgido una creciente preocupación académica y profesional por el establecimiento de un conjunto coherente de conceptos que sustenten el debido proceso en la emisión de normas de contabilidad y auditoría. Desde finales de los años sesenta, los organismos internacionales emisores de normas han buscado construir un marco conceptual para la contabilidad financiera, elaborado con base en la observación de la práctica contable y las metodologías de investigación propias de la filosofía de las ciencias. En Colombia, el proceso de normalización empezó hacia 1986 con la expedición del Decreto 2160. Esta medida revela la necesidad de construir políticas de estandarización de las prácticas contables y de generar un debate sobre la temática del marco conceptual en el contexto de la jurisdicción local y del desarrollo de la profesión y la disciplina contable, como herramienta fundamental del crecimiento económico y el bienestar social.

  9. Dynamic secondary ion mass spectrometry and X-ray photoelectron spectroscopy on artistic bronze and copper artificial patinas

    International Nuclear Information System (INIS)

    To prevent the natural processes of decay and to develop and improve the treatments of conservation and restoration of artistic bronzes meaning statues and sculptures, it is important understanding the patination processes and the knowledge of artificially corroded surfaces. Chemical and physical characterization of artificial patinas obtained on artistic bronzes and coppers by using the 19th century Western traditional patination techniques and recipes by means of SEM-EDS, light microscopy and ATR/FT-IR has been done in previous studies [I.Z. Balta, L. Robbiola, Characterization of artificial black patinas on artistic cast bronze and pure copper by using SEM-EDS and light microscopy, in: Proceedings of the 13th European Microscopy Congress, 22-27 August 2004, Antwerp, Belgium, EMC 2004 CD-Rom Conference Preprints; I.Z. Balta, L. Robbiola, Traditional artificial artistic bronze and copper patinas-an investigation by SEM-EDS and ATR/FT-IR, in: Proceedings of the 8th International Conference on Non Destructive Investigations and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage, 15-19 May 2005, Lecce, Italy, ART'05 CD-Rom Conference Preprints]. Differences in morphology (structure, thickness, porosity, adherence, compactity, uniformity, homogeneity) and also in composition, on both artistic cast bronze and pure copper patinas, were clearly evidenced. Further in-depth investigation is required to be carried out in order to better understand the patinas mechanisms of formation and the layers kinetics of growth. The elemental and chemical analysis, either on a surface monolayer or in a depth profile, by using the Secondary Ion Mass Spectrometry (SIMS) and X-ray Photoelectron Spectroscopy (XPS) techniques, can provide this kind of information, unique at trace-level sensitivity. SIMS has proved to be a suitable analytical technique for analyzing small amounts of material with high atomic sensitivity (ppm or even ppb) and high

  10. Application of X-Ray and Neutron Tomography to Study Antique Greek Bronze Coins with a High Lead Content

    International Nuclear Information System (INIS)

    Highly leaded bronze coins of the Coin Cabinet of the Kunsthistorisches Museum (KHM) show progressive corrosion as a result of unfavourable storage conditions within historic wooden cases. In connection to a research project concerning the preservation and conservation of the antique coins the causes for the sometimes severe corrosion were studied by different analytical techniques. Radiography and tomography investigations using neutrons and X-rays were performed at the Paul Scherrer Institute, i.e. the enrichment of lead in the interior of the objects was studied in a nondestructive manner. The tomography results obtained show that in addition to the lead rich areas on the obverse and reverse of the coins (often already clearly visible on the surface due to the formation of white corrosion products) a varying number of lead containing inclusions could be detected within the antique bronze coins. In addition, some information on their casting technique could be gained.

  11. Application of X-Ray and Neutron Tomography to Study Antique Greek Bronze Coins with a High Lead Content

    Science.gov (United States)

    Griesser, M.; Traum, R.; Vondrovec, K.; Vontobel, P.; Lehmann, E. H.

    2012-07-01

    Highly leaded bronze coins of the Coin Cabinet of the Kunsthistorisches Museum (KHM) show progressive corrosion as a result of unfavourable storage conditions within historic wooden cases. In connection to a research project concerning the preservation and conservation of the antique coins the causes for the sometimes severe corrosion were studied by different analytical techniques. Radiography and tomography investigations using neutrons and X-rays were performed at the Paul Scherrer Institute, i.e. the enrichment of lead in the interior of the objects was studied in a nondestructive manner. The tomography results obtained show that in addition to the lead rich areas on the obverse and reverse of the coins (often already clearly visible on the surface due to the formation of white corrosion products) a varying number of lead containing inclusions could be detected within the antique bronze coins. In addition, some information on their casting technique could be gained.

  12. Grain boundary segregation in a bronze-route Nb3Sn superconducting wire studied by atom probe tomography

    International Nuclear Information System (INIS)

    Atom probe tomography was used to characterize the A15 phase in a bronze-route Nb3Sn superconducting wire with a bronze matrix composition of Cu–8Sn–0.3Ti (in at.%). We observed depletion of niobium and segregation of Cu and Ti atoms at Nb3Sn grain boundaries. While the Nb depletion is about 15% relative to the grain interior, the average ratio between Cu and Ti excess values is 9 to 2. Segregation extends to a distance d ∼ 9 Å from the point of maximum Cu and Ti concentrations. Such local variation in the stoichiometry at the grain boundary region can be an additional source of flux-pinning in the Nb3Sn phase. Other microstructural parameters, such as the grain size and chemical composition of the Nb3Sn layer, were investigated by electron backscatter diffraction and transmission electron microscopy. (paper)

  13. Magnetization and Inter-Filament Contact in HEP and ITER Bronze-Route Nb(3)Sn Wires

    CERN Document Server

    Bordini, B; Devred, A; Richter, D; Bessette, D; Jewell, M; Bottura, L

    2011-01-01

    Magnetization measurements are relevant tests for the characterization of superconductors. Practically they are the only measurements that allow estimating the critical current density at low fields of low temperature superconductors, the effective filament size and the hysteresis losses. For this purpose CERN, in collaboration with the University of Geneva, has carried out magnetization measurements on five types of Nb(3)Sn wires: three bronze route strands used in the ITER project; one Powder In Tube (PIT) and one Internal Tin (IT) wires used for developing next generation accelerator magnets. The field dependent magnetization has been determined using three setups: a Vibrating Sample Magnetometer (VSM), a Superconducting Quantum Interference Device (SQUID) and a special system used for the production control of LHC strands. Samples of different lengths have been tested to check the different coupling between the filaments. Unexpectedly, it was found that the magnetization of the tested bronze wires was str...

  14. Magnetization and Inter-Filament Contact in HEP and ITER Bronze-Route Nb3Sn Wires

    CERN Document Server

    Bordini, B; Bottura, L; Devred, A; Jewell, M; Richter, D; Senatore, C

    2011-01-01

    Magnetization measurements are relevant tests for the characterization of superconductors. Practically they are the only measurements that allow estimating the critical current density at low fields of low temperature superconductors, the effective filament size and the hysteresis losses. For this purpose CERN, in collaboration with the University of Geneva, has carried out magnetization measurements on five types of Nb3Sn wires: three bronze route strands used in the ITER project; one Powder In Tube (PIT) and one Internal Tin (IT) wires used for developing next generation accelerator magnets. The field dependent magnetization has been determined using three set-ups: a Vibrating Sample Magnetometer (VSM), a Superconducting Quantum Interference Device (SQUID) and a special system used for the production control of LHC strands. Samples of different lengths have been tested to check the different coupling between the filaments. Unexpectedly, it was found that the magnetization of the tested bronze wires was stro...

  15. Electronic band structure and charge density wave transition in quasi-2D KMo6O17 purple bronze

    Science.gov (United States)

    Valbuena, M. A.; Avila, J.; Vyalikh, D. V.; Guyot, H.; Laubschat, C.; Molodtsov, S. L.; Asensio, M. C.

    2008-03-01

    High resolution angle-resolved photoemission of quasi-2D KMo6O17 purple bronze has been performed in the range from room temperature to 130 K, slightly above the charge density wave (CDW) transition (Tc = 110 K), and down to 35 K (well below Tc). In this paper we report a detailed study of how electronic band structure is affected by this transition driven by the hidden nesting scenario. The expected spectroscopic fingerprints of the CDW phase transition have been found and discussed according to the hidden one dimension and the development of a quasi-commensurate CDW. The excellent agreement between theory and our experimental results makes of potassium purple bronze a reference system for studying this type of instabilities.

  16. Electronic band structure and charge density wave transition in quasi-2D KMo6O17 purple bronze

    International Nuclear Information System (INIS)

    High resolution angle-resolved photoemission of quasi-2D KMo6O17 purple bronze has been performed in the range from room temperature to 130 K, slightly above the charge density wave (CDW) transition (Tc = 110 K), and down to 35 K (well below Tc). In this paper we report a detailed study of how electronic band structure is affected by this transition driven by the hidden nesting scenario. The expected spectroscopic fingerprints of the CDW phase transition have been found and discussed according to the hidden one dimension and the development of a quasi-commensurate CDW. The excellent agreement between theory and our experimental results makes of potassium purple bronze a reference system for studying this type of instabilities

  17. Development of technology and properties investigation of steel/bronze joints proposed for ITER HHF components manufacturing

    International Nuclear Information System (INIS)

    Full text of publication follows: During the development of ITER HHF components manufacturing it is necessary to provide reliable joints between heat sink material made of CuCrZr bronze and the supporting construction made of austenitic steel. Four different methods have been tried out: - Hot Isostatic Pressing (HIP), - HIP assisted brazing, - furnace assisted brazing, - Casting. The investigation of structure and properties of joints show that HIP and casting provide the better results than the other technologies. However, HIP is relatively expensive technology, and big size HIP furnace is required for the full scale components manufacturing that are not available n RF now. Therefore, casting was selected as a reference manufacturing technology for the primary wall of ITER modules n RF. The paper summarizes the results of bronze/steel joints manufacturing and investigation of their properties. (authors)

  18. Dynamic secondary ion mass spectrometry and X-ray photoelectron spectroscopy on artistic bronze and copper artificial patinas

    Science.gov (United States)

    Balta, I. Z.; Pederzoli, S.; Iacob, E.; Bersani, M.

    2009-04-01

    To prevent the natural processes of decay and to develop and improve the treatments of conservation and restoration of artistic bronzes meaning statues and sculptures, it is important understanding the patination processes and the knowledge of artificially corroded surfaces. Chemical and physical characterization of artificial patinas obtained on artistic bronzes and coppers by using the 19th century Western traditional patination techniques and recipes by means of SEM-EDS, light microscopy and ATR/FT-IR has been done in previous studies [I.Z. Balta, L. Robbiola, Characterization of artificial black patinas on artistic cast bronze and pure copper by using SEM-EDS and light microscopy, in: Proceedings of the 13th European Microscopy Congress, 22-27 August 2004, Antwerp, Belgium, EMC 2004 CD-Rom Conference Preprints; I.Z. Balta, L. Robbiola, Traditional artificial artistic bronze and copper patinas—an investigation by SEM-EDS and ATR/FT-IR, in: Proceedings of the 8th International Conference on Non Destructive Investigations and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage, 15-19 May 2005, Lecce, Italy, ART'05 CD-Rom Conference Preprints]. Differences in morphology (structure, thickness, porosity, adherence, compactity, uniformity, homogeneity) and also in composition, on both artistic cast bronze and pure copper patinas, were clearly evidenced. Further in-depth investigation is required to be carried out in order to better understand the patinas mechanisms of formation and the layers kinetics of growth. The elemental and chemical analysis, either on a surface monolayer or in a depth profile, by using the Secondary Ion Mass Spectrometry (SIMS) and X-ray Photoelectron Spectroscopy (XPS) techniques, can provide this kind of information, unique at trace-level sensitivity. SIMS has proved to be a suitable analytical technique for analyzing small amounts of material with high atomic sensitivity (ppm or even ppb) and high

  19. Burials, corpses and offerings in the Bronze Age of NW Iberia as agents of social identity and memory

    OpenAIRE

    Bettencourt, Ana M. S.

    2010-01-01

    In this text we analyse several materialities related to the world of death during the Bronze Age in the Northwest of the Iberian Peninsula with the purpose of discussing the long-term role of the corpses, the sepulchral places and the offerings as agents of legitimization of the territory, of memory and of creation and maintenance of the group identity. The first framed hypothesis is that there seems to be different conceptions of death between the highlands, associated with comm...

  20. Hollow Sodium Tungsten Bronze (Na0.15WO3) Nanospheres: Preparation, Characterization, and Their Adsorption Properties

    OpenAIRE

    Zuo Guanke; Guo He; Liu Hui; Zhang Jingyan; Hou Jing; Shen Guangxia; Cheng Ping; Guo Shouwu

    2009-01-01

    Abstract We report herein a facile method for the preparation of sodium tungsten bronzes hollow nanospheres using hydrogen gas bubbles as reactant for chemical reduction of tungstate to tungsten and as template for the formation of hollow nanospheres at the same time. The chemical composition and the crystalline state of the as-prepared hollow Na0.15WO3nanospheres were characterized complementarily, and the hollow structure formation mechanism was proposed. The hollow Na0.15WO3nanospheres sho...

  1. Feeding the periphery : modeling early Bronze Age economies and the cultural landscape of the Faynan District, Southern Jordan

    OpenAIRE

    Muniz, Adolfo A.

    2007-01-01

    The current study investigates the evolution of southern Levantine societies during the early Bronze Age (ca 3600- 2000 BCE). This study contributes to the reinvestigation of the food systems concept, a concept that addresses the interconnectivity of subsistence strategies and the larger natural and social environment. Investigating complex social processes within a food systems approach is not a new concept, but few systematic frameworks have modeled the scope and structure of varying levels...

  2. Oxygen isotope in archaeological bioapatites from India: Implications to climate change and decline of Bronze Age Harappan civilization

    OpenAIRE

    Anindya Sarkar; Arati Deshpande Mukherjee; Bera, M. K.; Das, B.; Navin Juyal; Morthekai, P.; Deshpande, R. D.; Shinde, V. S.; L. S. Rao

    2016-01-01

    The antiquity and decline of the Bronze Age Harappan civilization in the Indus-Ghaggar-Hakra river valleys is an enigma in archaeology. Weakening of the monsoon after ~5 ka BP (and droughts throughout the Asia) is a strong contender for the Harappan collapse, although controversy exists about the synchroneity of climate change and collapse of civilization. One reason for this controversy is lack of a continuous record of cultural levels and palaeomonsoon change in close proximity. We report a...

  3. The Metallurgy of the Sicilian Final Bronze Age/Early Iron Age necropolis of Madonna del Piano (Catania, Sicily)

    OpenAIRE

    Giumlia-Mair, Alessandra; Albanese Procelli, Rosa Maria; Lo Schiavo, Fulvia

    2010-01-01

    This paper presents the analysis results of the copper- based finds, from the important Sicilian necropolis of Madonna del Piano, near Grammichele (Catania), dated between the local Final Bronze Age 2 and the Early Iron Age IA. 122 copper-based finds from the 273 graves (1970-71) of the large cemetery have been analysed. The sampled objects belong to different classes, there are for instance weapons of offence and defence, such as swords and greaves, small decorative objects for personal use,...

  4. MEASURING AND MODELING OF THE MECHANICAL PROPERTIES OF COMPOSITE BEARING PAD MADE OF PLASTIC MATRIX AND FINE BRONZE ELASTIC SPRINGS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The viscoelastic properties of the normal PTFE plastic and strengthened PTFE plastic for bearing pad are measured. The mechanical properties of the composite material for bearing pad, which is made of the aforementioned plastics as matrix reinforced by fine bronze elastic springs, are modeled and relaxation modulus of the material are presented. The difference between these two kinds of PTFE is studied. The results show that the complex modulus of PTFE plastics for bearing pad is higher than that of normal PTFE plastics.

  5. Recent activity in development of bronze-processed Nb3Sn Wires. Improvements in strand performance and cabling

    International Nuclear Information System (INIS)

    Bronze-processed Nb3Sn wires have been used in practical applications of high-field magnets and large-scale magnets. Since the 1980s, Furukawa Electric Co., Ltd. has been developing and manufacturing many high-performance bronze-processed Nb3Sn wires. This paper describes our recent activity in development of the bronze-processed Nb3Sn wires. The non-Cu critical current density of the ITER-type strand was 1,150 A/mm2 at 12 T and 4.2 K, which is 1.8 times higher than that of the ITER-CS model coil 15 years ago. High-strength Nb3Sn wires reinforced with Cu-Ni/Nb-Ti or Cu-Nb composites have been successfully fabricated for high-field magnets. Enhancements of the superconducting properties resulting from pre-bending effects were demonstrated with Cu-Nb reinforced Nb3Sn wires. Mass production of practical cables for JT-60SA CS coils have been completed in exact accordance with the specifications. In addition, experimental manufacture of ITER-CSJA1 cables was properly carried out. Furthermore, a novel type of aluminum-alloy jacketed Nb3Sn conductor has been developed using the friction stir welding (FSW) technique. (author)

  6. Isotopic Evidence For The Primary Production, Provenance And Trade Of Late Bronze Age Glass In The Mediterranean.

    Science.gov (United States)

    Henderson, J.; Evans, J.; Nikita, K.

    The earliest known man made glass comes from Mesopotamia and dates to the 23rd century BC. By the 16th century BC the first glass vessels appear in Mesopotamia, but the earliest evidence for the fusion of glass from raw materials has been found at the 13th century BC Egyptian site of Qantir. Chemical analyses of this elite Late Bronze Age material have produced compositional distinctions between glasses found in Mesopotamia and Egypt. It is however debatable whether trace element concentrations provide a (geological) provenance for the glasses. By using neodymium and strontium isotopes to fingerprint well-dated chemically analysed 15th to 11th century BC glass samples, we show that independent primary production probably occurred in both Egypt and Mesopotamia in the 14th century BC, and that both of these areas exported glass to Greece. We also discuss the technological implications for glass manufacture and colouring that these new data provide. The results add significant new scientific evidence for glass trade between Late Bronze Age palatial societies. Moreover, it is the first time that this methodology has been used to investigate Bronze Age glass.

  7. Multipeak self-biased magnetoelectric coupling characteristics in four-phase Metglas/Terfenol-D/Be-bronze/PMN-PT structure

    Science.gov (United States)

    Huang, Dongyan; Lu, Caijiang; Bing, Han

    2015-04-01

    This letter develops a self-biased magnetoelectric (ME) structure Metglas/Terfenol-D/Be-bronze/PMN-PT (MTBP) consisting of a magnetization-graded Metglas/Terfenol-D layer, a elastic Be-bronze plate, and a piezoelectric 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (PMN-PT) plate. By using the magnetization-graded Metglas/Terfenol-D layer and the elastic Be-bronze plate, multi-peak self-biased ME responses are obtained in MTBP structure. The experimental results show that the MTBP structure with two layers of Metglas foil has maximum zero-biased ME voltage coefficient (MEVC). As frequency increases from 0.5 to 90 kHz, eleven large peaks of MEVC with magnitudes of 0.75-33 V/(cm Oe) are observed at zero-biased magnetic field. The results demonstrate that the proposed multi-peak self-biased ME structure may be useful for multifunctional devices such as multi-frequency energy harvesters or low-frequency ac magnetic field sensors.

  8. Multipeak self-biased magnetoelectric coupling characteristics in four-phase Metglas/Terfenol-D/Be-bronze/PMN-PT structure

    Directory of Open Access Journals (Sweden)

    Dongyan Huang

    2015-04-01

    Full Text Available This letter develops a self-biased magnetoelectric (ME structure Metglas/Terfenol-D/Be-bronze/PMN-PT (MTBP consisting of a magnetization-graded Metglas/Terfenol-D layer, a elastic Be-bronze plate, and a piezoelectric 0.67Pb(Mg1/3Nb2/3O3-0.33PbTiO3 (PMN-PT plate. By using the magnetization-graded Metglas/Terfenol-D layer and the elastic Be-bronze plate, multi-peak self-biased ME responses are obtained in MTBP structure. The experimental results show that the MTBP structure with two layers of Metglas foil has maximum zero-biased ME voltage coefficient (MEVC. As frequency increases from 0.5 to 90 kHz, eleven large peaks of MEVC with magnitudes of 0.75-33 V/(cm Oe are observed at zero-biased magnetic field. The results demonstrate that the proposed multi-peak self-biased ME structure may be useful for multifunctional devices such as multi-frequency energy harvesters or low-frequency ac magnetic field sensors.

  9. Bronze Age pottery from the Aeolian Islands: definition of Temper Compositional Reference Units by an integrated mineralogical and microchemical approach

    Science.gov (United States)

    Brunelli, D.; Levi, S. T.; Fragnoli, P.; Renzulli, A.; Santi, P.; Paganelli, E.; Martinelli, M. C.

    2013-12-01

    An integrated microchemical-petrographic approach is here proposed to discriminate the provenance of archaeological pottery artefacts from distinct production centres. Our study focuses on a statistically significant sampling ( n=186) of volcanic temper-bearing potteries representative of the manufacturing and dispersion among the islands of the Aeolian Archipelago during the Bronze Age. The widespread establishment of new settlements and the abundant recovery of Aeolian-made ceramic in southern Italy attest for the increased vitality of the Archipelago during the Capo Graziano culture (Early Bronze Age-Middle Bronze Age 2; 2300-1430 BC). Potteries from three of the main known ancient communities (Lipari, Filicudi and Stromboli) have been studied integrating old collections and newly excavated material. Volcanic tempers have been first investigated through multivariate analyses of relative abundances of mineral and rock clasts along with petrographic characters. In addition, we performed in-situ mineral chemistry microanalyses by Electron Microprobe and Laser Ablation—Inductively Coupled Plasma Mass Spectrometry to assess major and trace element composition of the most common mineral phases. Four Temper Compositional Reference Units have been recognised based on compositional trends. Two units (AI and AX) are unequivocally distinct by their peculiar trace element enrichment and petrographic composition; they mostly contain samples from the sites of Lipari and Stromboli, respectively. Units AIV and AVIII, restricted to the sites of Filicudi and Stromboli, show distinct petrographic characters but overlapped geochemical fingerprints.

  10. Bronze Age metal artefacts found on Cyprus - metal from Anatolia and the Western Mediterranean

    Directory of Open Access Journals (Sweden)

    Stos-Gale, Zofia A.

    2010-12-01

    Full Text Available Hundreds of Bronze Age metal artefacts excavated on archaeological sites in Cyprus have been analysed for their lead isotope and elemental composition in the Isotrace Laboratory, University of Oxford, in the years 1982-2002. In parallel, but in particular after 1995, hundreds of samples of minerals and slags collected from the mines and smelting sites around the Troodos Mountains were also analysed. Most of the results were published in various articles over the years, but the interpretation of some of the lead isotope data needs a current revision in view of new research conducted in Spain, Sardinia and southern France. It has been known that the lead isotope data for metal artefacts from the Cypriot Bronze Age sites shows that not all of the copper is consistent with origin from the Cypriot ores. In addition, the lead and silver artefacts found there must have been imported, because there are no lead or silver ores on Cyprus. The re-evaluation of the data shows that about 11 % of the analysed metal artefacts are consistent with the origin from the deposits in the Aegean and Turkey, while about 14 % with sources in the Western Mediterranean. This paper discusses in detail the current interpretation of the research into the sources of imported metal found in the Bronze Age context on Cyprus.

    Cientos de objetos de metal de la Edad del Bronce excavados en yacimientos de Chipre han sido analizados para conocer su composición elemental y sus isótopos de plomo en el Isotrace Laboratory de la Universidad de Oxford entre los años 1982 y 2002. Especialmente con posterioridad a 1995 cientos de muestras de minerales y escorias recogidas de minas y sitios de reducción de minerales localizadas en el entorno de las montañas de Troodos también fueron analizadas. La mayoría de los resultados fueron publicados en varios artículos a lo largo del tiempo, pero la interpretación de algunos análisis de isótopos de plomo necesitan de una revisión a

  11. Marco Polo - a mission to return a sample from a Near-Earth Object - science requirements and operational scenarios

    OpenAIRE

    Koschny, Detlef; Barucci, Antonella; Yoshikawa, Makoto; Böhnhardt, Hermann; Brucato, John; Coradini, Marcello; Dotto, Elisabetta; Franchi, Ian; Green, Simon F.; Josset, Jean-Luc; Kawaguchi, Junichiro; Michel, Patrick; Muinonen, Karri; Oberst, Jürgen; Yano, Hajime

    2009-01-01

    Marco Polo is a mission to return a sample from a Near-Earth Object of primitive type (class C or D). It is foreseen as a collaborative effort between the Japanese Space Agency (JAXA) and the European Space Agency (ESA). Marco Polo is currently in a Phase-A study. This paper focuses on the scientific requirements provided to the industrial study consortia in Europe as well as the possible mission scenario at the target object in order to achieve the overall mission science objectives. The ...

  12. Implicaciones del marco teórico de lo imaginario en la Psicología Social

    OpenAIRE

    Teresa Aracena Vicente

    2015-01-01

    En el presente estudio abordaremos dos de las principales concepciones sobre los mecanismos implicados en la construcción significativa del mundo. Hablamos de la Teoría de las Representaciones Sociales (TRS), formulada desde la psicología, y del marco teórico de lo imaginario, formulado principalmente desde la antropología y la filosofía. Procederemos exponiendo, primero, la TRS y, posteriormente, los acercamientos al marco teórico de lo imaginario desde diferentes disciplinas, para señalar l...

  13. Protection against inhaled oxidants through scavenging of oxidized lipids by macrophage receptors MARCO and SR-AI/II

    DEFF Research Database (Denmark)

    Dahl, Morten; Bauer, Alison K; Arredouani, Mohamed; Soininen, Raija; Tryggvason, Karl; Kleeberger, Steven R; Kobzik, Lester

    2007-01-01

    Alveolar macrophages (AMs) express the class A scavenger receptors (SRAs) macrophage receptor with collagenous structure (MARCO) and scavenger receptor AI/II (SRA-I/II), which recognize oxidized lipids and provide innate defense against inhaled pathogens and particles. Increased MARCO expression in......, consistent with SRA function in binding oxidized lipids. SR-AI/II-/- mice showed similar enhanced acute lung inflammation after beta-epoxide or another inhaled oxidant (aerosolized leachate of residual oil fly ash). In contrast, subacute ozone exposure did not enhance inflammation in SR-AI/II-/- versus SR-AI...

  14. MARCO LEGAL DEL CONTRATO DE ADHESIÓN EN EL COMERCIO ELECTRÓNICO Y LA TELEMÁTICA

    OpenAIRE

    José Arellano

    2004-01-01

    El objetivo de este trabajo se centró en analizar el marco legal del contrato de adhesión en el comercio electrónico. El tipo de investigación fue descriptiva, documental y cualitativa, con diseño no experimental documental bibliográfico. La técnica de recolección de datos fue una guía de observación, la cual permitió recabar la data pertinente al estudio, analizada en forma cualitativa. Los resultados indicaron que al analizar el marco jurídico de las partes (consentimiento, objeto y causa) ...

  15. The Bronze Age in the Northwestern of Iberian Peninsula: an analysis from funerary practices

    Directory of Open Access Journals (Sweden)

    Bettencourt, Ana M. S.

    2010-06-01

    Full Text Available From the analysis of the funerary practices and of their integration in the different chronological-cultural contexts where they develop, the author works out a new interpretation of the mechanism of negotiation of power and the promotion of social identity through the Bronze Age of the NW Iberian Peninsula. When studying an area so wide she distinguishes two great trends in the type and distribution of the funerary architectures throughout the Bronze Age that she associates with different ways of interaction with, and perception of, the world. Thus, she argues that the necropolises of “cloudy” tombs (cists without tumuli, plain graves and pits, located in areas of great agricultural potential and close to the settlements, may have been constructed by sedentary communities, very involved in agricultural activities, with a great sense of territoriality and a great control over, and deep knowledge of, the territory. On the other hand the communities involved with mountain landscapes, eventually more related to cattle and with ways of life that would imply greater mobility, were responsible for the construction of more visible funerary structures, such as small tumuli of megalithic tradition, located away from the settlements. In relation to the social role of the corpse, the author argues for the Early Bronze Age, that, the occupation of new territories, the emergence of a new form of community interaction with the environment and the emergence of new mechanisms of power and legitimacy of the territory were materialized in burial practices and in the social role of some corpses, in copper and gold grave goods. This social role was represented in old and new places. From the Middle Bronze Age she assumes that the corpse loses importance in collective terms and that death becomes more familiar. The new settings of power negotiation and social identity are transferred to other contexts of action more connected with the sphere of the living

  16. Release of copper from sintered tungsten-bronze shot under different pH conditions and its potential toxicity to aquatic organisms.

    Science.gov (United States)

    Thomas, Vernon G; Santore, Robert C; McGill, Ian

    2007-03-01

    Sintered tungsten-bronze is a new substitute for lead shot, and is about to be deposited in and around the wetlands of North America. This material contains copper in the alloyed form of bronze. This in vitro study was performed according to U.S. Fish and Wildlife Service criteria to determine the dissolution rate of copper from the shot, and to assess the toxic risk that it may present to aquatic organisms. The dissolution of copper from tungsten-bronze shot, pure copper shot, and glass beads was measured in a buffered, moderately hard, synthetic water of pH 5.5, 6.6, and 7.8 over a 28-day period. The dissolution of copper from both the control copper shot and the tungsten-bronze shot was affected significantly by the pH of the water and the duration of dissolution (all p valueswater quality criteria database, were all far less than the 0.1 criterion value. Given the conditions stipulated by the U.S. Fish and Wildlife Service and the U.S. Environmental Protection Agency, heavy loading from discharged tungsten-bronze shot would not pose a toxic risk to potable water, or to soil. Consequently, it would appear that no toxic risks to aquatic organisms will attend the use of tungsten-bronze shot of the approved composition. Given the likelihood that sintered tungsten-bronze of the same formula will be used for fishing weights, bullets, and wheel balance weights, it is expected that the use of this new material in these applications will not be associated with toxic risks to aquatic life. PMID:17276492

  17. A family of rare earth molybdenum bronzes: Oxides consisting of periodic arrays of interacting magnetic units

    International Nuclear Information System (INIS)

    The family of rare earth molybdenum bronzes, reduced ternary molybdates of composition LnMo16O44, was synthesized and a detailed structural study carried out. Bond valence sum (BVS) calculations clearly show that the molybdenum ions in tetrahedral coordination are hexavalent while the electron count in the primitive unit cell is odd. Yet, measurements show that the phases are semiconductors. The temperature dependence of the magnetic susceptibility of samples containing several different rare earth elements was measured. These measurements verified the presence of a 6.5 K magnetic phase transition not arising from the rare earth constituent, but likely associated with the unique isolated ReO3-type Mo8O36 structural subunits in this phase. To better understand the behavior of these materials, electronic structure calculations were performed within density functional theory. Results suggest a magnetic state in which these structural moieties have an internal ferromagnetic arrangement, with small ~1/8 μB moments on each Mo. We suggest that the Mo8O36 units behave like pseudoatoms with spin 1/2 derived from a single hole distributed over the eight Mo atoms that are strongly hybridized with the O atoms of the subunit. Interestingly, while the compound is antiferromagnetic, our calculations suggest that a field-stabilized ferromagnetic state, if achievable, will be a narrow band half-metal. - Graphical abstract: LnMo16O44 phases comprise corner sharing tetrahedral and octahedral molybdenum ions. The MoO6 octahedra form Mo8O36 units that are well separated and act like pseudo-atoms, accommodating 11 electrons each. - Highlights: • Single crystal X-ray diffraction refinements of LnMo16O44 single crystals for Ln=Ce, Pr, Nd, Tb, Dy and Ho. • DFT calculations based on LaMo16O44. • [Mo8O36] units behaving as superatoms with a net magnetic moment of 1 µB. • Bronze structure containing equal number of molybdenum tetrahedra and octahedral

  18. Alloy characterization of a 7th Century BC archeological bronze vase — Overcoming patina constraints using Monte Carlo simulations

    Energy Technology Data Exchange (ETDEWEB)

    Manso, M. [Laboratório de Instrumentação, Engenharia Biomédica e Fisica da Radiação (LIBPhys-UNL), Departamento de Fisica, Faculdade de Ciências e Tecnologias, Universidade Nova de Lisboa, 2829-516 Monte da Caparica (Portugal); Faculdade de Belas-Artes da Universidade de Lisboa, Largo da Academia Nacional de Belas-Artes, 1249-058 Lisboa (Portugal); Schiavon, N. [Hercules Laboratory, University of Évora, Palácio do Vimioso,Largo Marquês de Marialva 8, 7000-809 Évora Portugal (Portugal); Queralt, I. [Laboratory of X-ray Analytical Applications, Institute of Earth Sciences Jaume Almera, CSIC, Solé Sabaris s/n, 08028 Barcelona (Spain); Arruda, A.M. [Centro de Arqueologia da Universidade de Lisboa (UNIARQ), Alameda da Universidade, 1600-214 Lisboa (Portugal); Sampaio, J.M. [BioISI — Biosystems & Integrative Sciences Institute, Faculdade de Ciências da Universidade de Lisboa (Portugal); Brunetti, A., E-mail: brunetti@uniss.it [Department of Political Science and Communication, University of Sassari, Via Piandanna 2, 07100 Sassari (Italy)

    2015-05-01

    In this work we evaluate the composition of a bronze alloy using X-ray fluorescence spectrometry (XRF) and Monte Carlo (MC) simulations. For this purpose, a 7th Century BC archeological vase from the SW Iberian Peninsula, displaying a well formed corrosion patina was analyzed by means of a portable X-ray fluorescence spectrometer. Realistic MC simulations of the experimental setup were performed with the XRMC code package which is based on an intensive use of variance-reduction techniques and uses XRAYLIB a constantly updated X-ray library of atomic data. A single layer model was applied for simulating XRF of polished/pristine bronze whereas a two-or-three-layer model was developed for bronze covered respectively by a corrosion patina alone or coupled with a superficial soil derived crust. These simulations took into account corrosion (cerussite (PbCO{sub 3}), cuprite (Cu{sub 2}O), malachite (Cu{sub 2}CO{sub 3}(OH){sub 2}), litharge (PbO)) and soil derived products (goethite (FeO(OH)) and quartz (SiO{sub 2})) identified by means of X-ray diffraction and Raman micro analytical techniques. Results confirm previous research indicating that the XRF/Monte Carlo protocol is well suited when a two-layered model is considered, whereas in areas where the patina + soil derived products' crust is too thick, X-rays from the alloy substrate are not able to exit the sample. Quantitative results based on MC simulations indicate that the vase is made of a lead–bronze alloy: Mn (0.2%), Fe (1.0%), Cu (81.8%), As (0.5%), Ag (0.6%), Sn (8.0%) and Pb (8.0%). - Highlights: • We study an archeological bronze vase with patina corrosion using XRF spectrometry. • The experimental setup is modeled using Monte Carlo (MC) simulations. • Combining MC simulations with XRF it is possible to derive concentrations. • We demonstrated that this is possible without removing the patina.

  19. Alloy characterization of a 7th Century BC archeological bronze vase — Overcoming patina constraints using Monte Carlo simulations

    International Nuclear Information System (INIS)

    In this work we evaluate the composition of a bronze alloy using X-ray fluorescence spectrometry (XRF) and Monte Carlo (MC) simulations. For this purpose, a 7th Century BC archeological vase from the SW Iberian Peninsula, displaying a well formed corrosion patina was analyzed by means of a portable X-ray fluorescence spectrometer. Realistic MC simulations of the experimental setup were performed with the XRMC code package which is based on an intensive use of variance-reduction techniques and uses XRAYLIB a constantly updated X-ray library of atomic data. A single layer model was applied for simulating XRF of polished/pristine bronze whereas a two-or-three-layer model was developed for bronze covered respectively by a corrosion patina alone or coupled with a superficial soil derived crust. These simulations took into account corrosion (cerussite (PbCO3), cuprite (Cu2O), malachite (Cu2CO3(OH)2), litharge (PbO)) and soil derived products (goethite (FeO(OH)) and quartz (SiO2)) identified by means of X-ray diffraction and Raman micro analytical techniques. Results confirm previous research indicating that the XRF/Monte Carlo protocol is well suited when a two-layered model is considered, whereas in areas where the patina + soil derived products' crust is too thick, X-rays from the alloy substrate are not able to exit the sample. Quantitative results based on MC simulations indicate that the vase is made of a lead–bronze alloy: Mn (0.2%), Fe (1.0%), Cu (81.8%), As (0.5%), Ag (0.6%), Sn (8.0%) and Pb (8.0%). - Highlights: • We study an archeological bronze vase with patina corrosion using XRF spectrometry. • The experimental setup is modeled using Monte Carlo (MC) simulations. • Combining MC simulations with XRF it is possible to derive concentrations. • We demonstrated that this is possible without removing the patina

  20. The fallacy of "equal treatment" in Brazil's bill of rights for internet users A falácia da "igualdade de tratamento" na carta brasileira de direitos dos usuários da internet

    Directory of Open Access Journals (Sweden)

    J. Gregory Sidak

    2012-12-01

    Full Text Available The "Brazilian bill of rights for internet users," or "marco civil," has been under consideration at the brazilian congress since 2011. Marco civil's provisions for network neutrality have been particularly controversial. Proponents of network neutrality in Brazil advocate for the "equal treatment" of all data packets, including banning internet service providers from offering to content providers the option to purchase enhanced quality of service in the delivery of data packets. These network neutrality rules conflict with the other goals and principles of marco civil-particularly goals to promote internet access, to foster innovation, and to protect the constitutional right of freedom of speech and the free flow of information.A "carta Brasileira de direitos dos usuários da internet," ou "marco civil," tramita no congresso Brasileiro desde 2011. As disposições do marco civil relativas à neutralidade de rede são particularmente controversas. Os defensores da neutralidade de rede no Brasil advogam pela "igualdade de tratamento" de todos os pacotes de dados, inclusive proibindo que provedores de serviço de acesso à internet ofereçam aos provedores de conteúdo a opção de adquirir uma melhor qualidade de serviço na entrega de pacotes de dados. Essas disposições relativas à neutralidade de rede conflitam com outros objetivos e princípios do marco civil - especialmente os objetivos de promover o acesso à internet, promover a inovação, e garantir o direito constitucional de liberdade de expressão e informação.

  1. Teoría de los marcos relacionales y la trasformación de las funciones del estímulo

    Directory of Open Access Journals (Sweden)

    Simon Dymond

    2005-01-01

    Full Text Available La teoría de los marcos de relaciones es una teoría y tecnología moderna del lenguaje y la cognición que hace gran énfasis en la trasformación de funciones de estímulo de acuerdo con las relaciones múltiples del estímulo. Revisamos la investigación reciente sobre la trasformación de las funciones de estímulo y argumentamos que la trasformación derivada posee importancia clínica, no solo porque da cuenta de la emergencia de nuevas respuestas ante estímulos previamente neutrales en ausencia de condicionamiento directo, sino porque también ayuda a explicar el desarrollo de nuevas estrategias de evitación y su rápida generalización. Posteriormente se delinean posibles restricciones sobre el efecto de la trasformación derivada por formas físicas del estímulo. En conclusión, el análisis básico y aplicado en curso del fenómeno de la trasformación de funciones representa uno de los más importantes desafíos y oportunidades para el análisis moderno de la conducta

  2. Los países del Este y la transición al mercado: hacia la formación del marco institucional

    Directory of Open Access Journals (Sweden)

    Luis Fernando Macias

    1994-01-01

    Full Text Available La transición al mercado ha sido para los países del Este de Europa el paso de la euforia inicial al desengaño generalizado. Las medidas adoptadas por los nuevos dirigentes con el propósito de reanimar la economía y sacarla de la crisis han conducido a lo contrario: la caída de la producción, la aparición del desempleo y el desplome del nivel de vida. Esta situación lleva al autor a través del artículo y a la luz de los acontecimientos recientes en la región, que han conducido a una modificación de las formas de propiedad dominantes existentes durante el período del socialismo real, a plantear la necesaria redefinición del marco socio-institucional que conduzca no sólo al desmonte del sistema centralista-burocrático de gestión, sino que se dirija también, y ésto es lo fundamental, al normal funcionamiento de una economía de mercado. Es esto último lo que el artículo se encarga de desglosar mientras explica, en ese nuevo contexto, los cambios que se deben realizar tanto en el factor humano corno en los sistemas legal y contable.

  3. Uranium in the Surrounding of San Marcos-Sacramento River Environment (Chihuahua, Mexico)

    Science.gov (United States)

    Rentería-Villalobos, Marusia; Cortés, Manuel Reyes; Mantero, Juan; Manjón, Guillermo; García-Tenorio, Rafael; Herrera, Eduardo; Montero-Cabrera, Maria Elena

    2012-01-01

    The main interest of this study is to assess whether uranium deposits located in the San Marcos outcrops (NW of Chihuahua City, Mexico) could be considered as a source of U-isotopes in its surrounding environment. Uranium activity concentrations were determined in biota, ground, and surface water by either alpha or liquid scintillation spectrometries. Major ions were analyzed by ICP-OES in surface water and its suspended matter. For determining uranium activity in biota, samples were divided in parts. The results have shown a possible lixiviation and infiltration of uranium from geological substrate into the ground and surface water, and consequently, a transfer to biota. Calculated annual effective doses by ingestion suggest that U-isotopes in biota could not negligibly contribute to the neighboring population dose. By all these considerations, it is concluded that in this zone there is natural enhancement of uranium in all environmental samples analyzed in the present work. PMID:22536148

  4. Solar EUV irradiance from the San Marco ASSI - A reference spectrum

    Science.gov (United States)

    Schmidtke, Gerhard; Woods, Thomas N.; Worden, John; Rottman, Gary J.; Doll, Harry; Wita, Claus; Solomon, Stanley C.

    1992-11-01

    The only satellite measurement of the solar EUV irradiance during solar cycle 22 has been obtained with the Airglow Solar Spectrometer Instrument (ASSI) aboard the San Marco 5 satellite flown in 1988. The ASSI in-flight calibration parameters are established by using the internal capabilities of ASSI and by comparing ASSI results to the results from other space-based experiments on the ASSI calibration rocket and the Solar Mesospheric Explorer (SME). A solar EUV irradiance spectrum derived from ASSI observations on November 10, 1988 is presented as a reference spectrum for moderate solar activity for the aeronomy community. This ASSI spectrum should be considered as a refinement and extension of the solar EUV spectrum published for the same day by Woods and Rottman (1990).

  5. Marco conceptual para la evaluación de programas de salud

    Directory of Open Access Journals (Sweden)

    Montero Rojas, Eiliana

    2004-03-01

    Full Text Available La evaluación como disciplina es un área relativamente nueva de las Ciencias Sociales; consecuentemente, su incorporación explícita en los programas y sistemas de salud ha llegado algo tardíamente. Este artículo presenta elementos de un marco conceptual para concebir y utilizar la evaluación en programas de salud. Se define la evaluación como una herramienta para la toma de decisiones, se discuten tendencias y temáticas de actualidad en el campo y también conceptos clave tales como teoría del programa y valoración de necesidades. Finalmente, se esboza una primera aproximación a dos constructos de gran interés en la evaluación de programas de salud: calidad y equidad.

  6. Interacción universidad y entorno: marco para el emprendimiento

    Directory of Open Access Journals (Sweden)

    Pedro Emilio Sanabria-Rangel

    2015-01-01

    Full Text Available El documento desarrolla el tema de la relación universidad-entorno, especialmente en lo que se refiere a la vinculación con el sector productivo como parte del desarrollo de la función de extensión universitaria. El propósito fundamental es proporcionar un marco de referencia para la creación o justificación de las unidades de emprendimiento universitarias como mecanismo de enlace para el desarrollo de la función extensión desde una de sus aproximaciones: el enfoque empresarial. Como resultado, se evidencian los enfoques, los modelos, los mecanismos y las estrategias de interacción universidad-entorno; se realiza una reflexión sobre el emprendimiento como medio para dicha interacción y se muestran las condiciones estructurales que favorecen el emprendimiento universitario.

  7. Espacio Europeo de Educación Superior. Situación actual. Marco legislativo.

    OpenAIRE

    Maciá Soler, Loreto; Moncho Vasallo, J.; Zabalegui Yárnoz, A.; Ricomá Muntané, R.; Nuin Orrio, C.; Mariscal Crespo, M.I.; Pedraz Marcos, A.; Márquez Membrive, J.; Germán Bes, C.

    2006-01-01

    El objetivo de este artículo es realizar un análisis de la legislación actual y la repercusión del cambio ya iniciado en algunas titulaciones como es el caso de Enfermería en el marco académico de la Educación Superior, reforma importante del Sistema Universitario Español. Para ello se revisa el contenido y análisis de la documentación publicada en el Ministerio de Educación relativa a Educación Superior; la legislación vigente española y la legislación Comunitaria con obj...

  8. Marco de trabajo de presentación para aplicaciones J2EE : MTP

    OpenAIRE

    Alonso de Motta, José

    2012-01-01

    Diseño e implementación de un marco de trabajo de presentación para aplicaciones J2EE. Análisis de los frameworks de mercado Struts 2, JavaServer Faces y Spring MVC. Patrones de diseño MVC, Core J2EE Patterns y patrones de diseño para programación orientada a objetos (Design Patterns, Elements of Reusable Object-Oriented Software). Aplicación de autoservicio de socios para una asociación de padres y madres de alumnos para demostración de uso del framework MTP y de la definición de una arquite...

  9. Inequidad y desigualdad sanitaria en el marco de los determinantes sociales de la salud

    Directory of Open Access Journals (Sweden)

    Sagrario Lobato Huerta

    2010-04-01

    Full Text Available En el marco de los determinantes sociales de la salud, las inequidades sanitarias son entendidas como desigualdades injustas y prevenibles. La inequidad se basa en juicios éticos; por ello, sediferencia de la desigualdad, debido a que la primera hace referencia a lo injusto de una desigualdad. Se propone entonces que la igualdad sanitaria remita a la del derecho humano a la salud y la equidad sanitaria a la prestación de servicios de salud, según las necesidades de la población y su perfil patológico, intensificandoacciones en los grupos más vulnerables e incidiendo en las causas sociales de esa vulnerabilidad. Por tanto, las políticas de salud deben ser parte de un proceso que cuestione y transforme las relaciones en el sistema económico y político actual.

  10. Holes in teeth - Dental caries in Neolithic and Early Bronze Age populations in Central Germany.

    Science.gov (United States)

    Nicklisch, Nicole; Ganslmeier, Robert; Siebert, Angelina; Friederich, Susanne; Meller, Harald; Alt, Kurt W

    2016-01-01

    This study provides diachronic insight into the epidemiology of carious defects in teeth of Neolithic and Early Bronze Age populations in Central Germany over a period of 4000 years. The data were retrieved from skeletal remains uncovered at 21 sites throughout the Middle Elbe-Saale region (MES), comprising a total of 494 individuals with preserved teeth. The data generated were examined for age- and sex-related differences in order to gain information about the dietary habits and socio-economic structures of the period with the goal of identifying potential diachronic changes. The results indicated that dietary habits changed over the course of the Neolithic period: the prevalence of caries significantly decreased between the Early and Late Neolithic. The adults from the Early Neolithic sample, particularly those from the LBK bore the highest rate of caries. This highlights the essential importance of cereals in the diet of the early farmers in the Middle Elbe-Saale region. As time went on, meat and dairy products became more and more important, which had a positive impact on dental health. The data also show sex-specific differences: women were more often affected by caries than men and female jaws also generally exhibited greater numbers of carious teeth than their male counterparts. Dental health is a reflection of both biological factors and of economic and sociocultural structures. PMID:25765291

  11. The water clock of the Bronze Age (Northern Black Sea Coast)

    CERN Document Server

    Vodolazhskaya, Larisa N; Nevsky, Mikhail Yu

    2015-01-01

    In the article presents the results of the multidisciplinary study conducted with the help of archaeological, physical and astronomical methods. The aim of the study was to analyze and interpret marks and drawings applied to the surface of the vessel of the Bronze Age (Srubna culture) found near the Staropetrovsky village (Donetsk region, Ukraine) near the border between the Donetsk and Lugansk regions. The carried out calculations and measurements possible to prove that staropetrovsky vessel is the most ancient water clock, discovered on the territory of Europe, and have approximately the same age as the oldest known ancient Egyptian water clock. Such vessels - water clocks were needed for Srubna population to mark sundial, which had recently been discovered in the Northern Black Sea Coast. Based on the analysis of marks on the outside of the vessel, it was revealed that Staropetrovsky vessel is unique ancient complex device for measuring time and at the same time using a water clock, and with the help of a ...

  12. Leather material found on a 6th B.C. Chinese bronze sword: A technical study

    Science.gov (United States)

    Luo, Wugan; Si, Yi; Wang, Hongmin; Qin, Ying; Huang, Fengchun; Wang, Changsui

    2011-09-01

    During July to November, 2006, an important archaeological excavation was conducted in Yun country, Hubei province, southern China. Chinese archaeologists found some remnant of leather materials, covered with red pigments, on a 6th century B.C. Chinese bronze sword. To understand the technology/ies that may have been utilized for manufacturing the leathers, a combined of Raman spectroscopy, FT-IR and XRF was thus applied to the remnant of leather materials. Raman analyses showed that red pigment on the leather was cinnabar (HgS). FT-IR and XRF analyses indicated that the content of some elements, such as Ca (existing as CaCO 3) and Fe (existing as Fe 2O 3), were much higher than those in the surrounding grave soil. The results inferred an application of lime depilation and retting, and the Fe-Al compound salt as tanning agent. And it was furthermore implicated that the Fe-Al salt tanning technique had been developed in the middle and late Spring and Autumn Period of China.

  13. The Luttinger liquid theory of molybdenum purple bronze Li0.9Mo6O19

    International Nuclear Information System (INIS)

    We study a quasi-1D material, the purple bronze Li0.9Mo6O19 which becomes superconductor at 1.9 K. Firstly, the band structure is calculated by use of ab-initio DFT-LMTO method. The unusual, very 1-dimensional band dispersion obtained in previous band calculations is confirmed and the overall band structure agrees reasonably with existing photoemission data. Dispersion perpendicular to the main dispersive direction is obtained and investigated in detail. Temperature and disorder effects are evaluated, in particular we check their influence on the band broadening. Based on this, in the second part of our work we derive an effective low energy theory within the Luttinger liquid framework. We estimate the strength of possible instabilities and values of charge modes compressibilities. Our aim is to understand experimental findings, in particular the ones which are certainly lying within 1D regime. We discuss the validity of our approach and further perspectives for the lower energy phases.

  14. Astronomical Interpretation of the Signs on the Vessel of the Bronze Age (Central Donbass)

    CERN Document Server

    Vodolazhskaya, Larisa N; Nevsky, Mikhail Yu

    2015-01-01

    The article presents the results of multidisciplinary study carried out with the help of archaeological and astronomical methods. The aim of the study was to analyze and interpret the signs - elements of the composition, incised on the outer side surface of the vessel of the Late Bronze Age, owned to Srubna culture and discovered near the Staropetrovsky village in the northeast of the Donetsk region. The measurements and astronomical calculations revealed that all signs have astronomical meaning. Fourray star has been interpreted as the star Sirius. The sign polyline has been interpreted as an analog of graphic of equation of time in which the testimony of a water clock correspond with average solar time, and the testimony of a sundial - the true solar time. Sign wheel has been interpreted as a complex of lines, reflecting the regularity changing the direction of the shadows from the gnomon at sunset at the equinoxes and solstices. The sign thin polyline has been interpreted as a symbol of change of height of...

  15. Electrochemical zinc insertion into W18O49: Synthesis and characterization of new bronzes

    International Nuclear Information System (INIS)

    Divalent zinc ions have been electrochemically inserted into W18O49, producing zinc bronzes. Under our experimental conditions, W18O49 accepts zinc reversibly as a guest up to 0.9 ions per formula. The reaction seems to proceed through the formation of a solid solution in which the W-O framework of the parent oxide is maintained. The location of the Zn2+ ions in the framework of W18O49 has been determined by neutron diffraction on a chemically prepared sample having the composition Zn0.34W18O49. As a main result, we found that Zn prefers to insert in one of the four types of quadrangular tunnels. More precisely, it is displaced from the center to occupy a low coordination site. This result indicates that a significant covalent character exists in the Zn-O bond. - Graphical Abstract: The structure of Zn0.36W18O49 projected along the b-axis

  16. Demonstration of Neutron Resonance capture applied to a Cultural Heritage study of Antique Benin Bronzes

    International Nuclear Information System (INIS)

    In many cases of historical and archaeological studies physical techniques Instrumental Neutron Activation Analysis (INAA) X-Ray Fluorescence (XRF) and Proton Induced X-ray Emission (PIXE) are used to get information about the element composition of objects. INAA is usually carried out using small samples taken from the object . XRF and PIXE only yield surface information, and require cleaning of the surface to suppress the effect of external contamination. Such actions on artefacts are unwanted. Recently neutron capture resonances have been used to identify elements in artefacts using a set of γray detectors and a time-of flight system at the GELINA facility. This allows identification and quantification of elements of precious artefacts in an fully non-destructive way and with very little activation Because of the novelly of the method the principles of neutron resonance capture analysis (NRC A) will be discussed and the results of an applications to a comparative study of two Benin Bronzes presented

  17. Middle Bronze Age funerary hipogea from Torre Velha 3 (Serpa, Portugal. The Southeast inside the Southwest?!

    Directory of Open Access Journals (Sweden)

    Catarina ALVES

    2011-04-01

    Full Text Available Recent archaeological excavations in the Portuguese region of Baixo Alentejo, carried out under the implementation of the irrigation project connected with the Alqueva Dam (EDIA, have brought to light important finds dated to the Southwestern Bronze Age. In this article, the first data of one of the largest funerary hipogea assemblages, found in Torre Velha 3 (Serpa, are presented. The funerary contexts show similarities with those from the Argaric Culture, namely as far as the rituals, architecture and offered items are concerned. Each funerary structure is composed of an atrium connect with a chamber (an artificial cave cut into the rock closed by vertical slabs. Normally individuals were inhumated in a flexed position inside the chamber. Grave goods consist in pottery, metal artifacts and also meat offerings which point out to a ritual of commensality performed when the burial took place. Radiocarbon dating of bone samples taken from the meat offerings allowed ascribing to these hipogea a chronology on the second quarter/ beginning of the third quarter of the II Millennium BC.

  18. Computer simulation study of hexagonal tungsten oxide and its sodium bronzes

    International Nuclear Information System (INIS)

    The authors have used theoretical, computer based atomistic simulation techniques to investigate the transport properties of the sodium ions in hexagonal tungsten trioxide. Two approaches were taken. Firstly, using perfect lattice simulation methods, the hexagonal structure of WO/sub 3/ was modelled. The interatomic potentials were taken from an earlier study of crystallographic shear planes in WO/sub 3/. The results compared very well with the observed structure; the good agreement encouraged the authors to continue with a simulation of the sodium bronzes, using defeat lattic calculations. In the second approach, they investigated the behaviour of individual sodium ions and their interaction with the lattice, using defect energy calculations. The program used for this was CASCADE, a vectorized version of HADES III, implemented on the Cray-1 at the University of London. Insertion of Na+ to WO/sub 3/ requires the addition of an electron to the conduction band in order to maintain electroneutrality. The authors treated this electron as being localised on a tungsten cation, an assumption they feel is reasonable, given the semiconducting behavior found for Na/sub x/WO/sub 3/ at low values of x. They found that a single Na/sup +/ ion produced very little distortion of the surrounding lattice, a result that reflects the relative sizes of the ion and the tunnel and is, of course, a requirement for fast ion conduction

  19. The examination, analysis and conservation of a bronze Egyptian Horus statuette

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A. [Conservation Department, Ditsong: National Museum of Cultural History, PO Box 28088, Sunnyside, Pretoria 0132 (South Africa); Botha, H. [South African Institute for Objects Conservation, PO Box 122, Joubertina 6410 (South Africa); Beer, F.C. de, E-mail: frikkie.debeer@necsa.co.za [Radiation Science, Necsa, PO Box 582, Pretoria 0001 (South Africa); Ferg, E. [Department of Chemistry, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

    2011-09-21

    The production techniques, corrosive deterioration, conservation and questions regarding authenticity of a small Egyptian bronze statuette of the Child Horus (in the collection of the Ditsong: National Museum of Cultural History in Pretoria) was scientifically examined and analysed. The statuette dates to Egypt's 12th Dynasty. When the statuette was damaged, it was considered the appropriate time to obtain valuable information about its history and background through scientific research. Neutron tomography (NT), a relatively new non-destructive technique (NDT) to the South African R and D community to study museum objects, was applied to perform this research. The results from NT were supported by additional tests done through XRF and XRD analyses of samples taken from the damaged statuette. Results revealed that the lost-wax method was used in the manufacturing process. The extent of the restoration and materials used can be verified and as a result the deterioration of the object can now be monitored. This paper describes in detail the analytical techniques used in the study and how it contributed to the conservation of the statuette and its authenticity.

  20. Sliding Wear Response of a Bronze Bushing: Influence of Applied Load and Test Environment

    Science.gov (United States)

    Prasad, B. K.

    2012-10-01

    This investigation pertains to the examination of the sliding wear behavior of a leaded-tin bronze bushing under the conditions of varying applied loads and test environments against a steel shaft. The test environment was changed by adding 5% of solid lubricants like talc and lead to an oil lubricant separately as well as in combination; the fraction of the two (solid) lubricants within the solid lubricant mixture was varied in the range of 25-75% in the latter case. The wear performance of the bushing was characterized in terms of the wear rate, frictional heating, and friction coefficient. The increasing load led to deterioration in the wear response, while the addition of the solid lubricant particles produced a reverse effect. Further, an appreciable difference in the wear behavior was not observed when the tests were conducted in the oil plus talc and oil plus lead lubricant mixtures. However, the oil containing lead and talc together brought about a significant improvement in the wear response; best results were obtained in the case of the lubricant mixture consisting of lead and talc together in the ratio of 3:1 in the oil. The observed wear behavior of the samples has been discussed in terms of specific characteristics of various microconstituents. The features of the wear surfaces and subsurface regions further substantiated the wear response and enabled us to understand the operating material removal mechanisms.

  1. Electrochemical and spectroscopic evidences of corrosion inhibition of bronze by a triazole derivative

    International Nuclear Information System (INIS)

    The electrochemical behavior of the bronze (Cu-8Sn in wt%) was investigated in 3% NaCl aqueous solution, in presence and in absence of a corrosion inhibitor, the 3-phenyl-1,2,4-triazole-5-thione (PTS). The inhibiting effect of the PTS was evidenced for concentrations higher than 1 mM for the cathodic process whereas its effect was clearly seen with a concentration as low as 0.1 mM for the anodic process. A significant positive shift of the corrosion potential was also observed, and its inhibiting effect increased with both its concentration and the immersion time of the sample. From voltammetry and electrochemical impedance spectroscopy experiments, the inhibiting efficiency of the PTS was found to be in the 94-99% range for 1 mM concentration. Scanning electron microscopy and X-ray energy dispersion analysis of the specimen surface show the presence of sulphur on the surface. Raman micro-spectrometry study confirms the protective effect of the PTS in aqueous solution through three types of interactions with the electrode, namely the adsorption of the inhibitor in a flat configuration, the formation of copper-thiol molecules, and when copper is released, the formation of a polymeric complex

  2. High temperature performance of arc-sprayed aluminum bronze coatings for steel

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhong-li; LI De-yuan; WANG Shui-yong

    2006-01-01

    The high-temperature oxidation behavior of arc-sprayed aluminum bronze coatings on steel substrate was studied during isothermal exposures in air at 900 ℃. The surface morphologies and interface of the coatings after isothermal oxidation at 900 ℃ for different times were observed. The experiments showed that the coatings on steel substrate were not deteriorated and the substrate was protected well, being exposed to high temperatures up to 900 ℃. The coatings withstood more than ten times thermal shock tests without any coating separation. The thermal expansion coefficient of the coatings was measured, revealing not much difference between it and that of steel substrate. After exposure at high temperature, the coatings were still adhered to steel substrate well.Isothermal mass gain of the coatings at elevated temperature in dry air was measured by means of a thermal balance and the oxidation behavior was evaluated by oxidation kinetic curves, exhibiting the oxidation kinetics curve accorded with a parabolic law.The parabolic rate constant of the oxidation kinetic curve is 1.02× 10-9 g2·cm-4·s-1 for the first 60 min and from 150 min to 2 880 min the constant is 5.1 × 10-12 g2·cm-4·s-1.

  3. Effect of Annealing Atmosphere on the Mechanical Property of Free-cutting Phosphor Bronze Alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The present work is focused on the influence of annealing atmosphere on the microstructure and mechanical property of free-cutting phosphor bronze alloy. The annealing of the alloy was conducted in the three kinds of annealing atmosphere such as air, vacuum and nitrogen. After annealing, a discernable difference in recystallized grain size and lead particle size was not appeared with different annealing atmosphere. The tensile strength of the alloy annealed in air or nitrogen atmosphere was higher than that of those annealed in vacuum atmosphere. In thecase of the alloy annealed in vacuum atmosphere, the mechanical strength was reduced by vaporization of zinc. In the case of annealing in nitrogen and in air atmosphere, the sweating of lead was occurred. However, the inverse segregation of lead was suppressed by copper oxide layer on the surface annealed in air. This copper oxide layer leads to a decrease of the yield during fabrication process. Therefore, annealing of the alloy in nitrogen atmosphere is favorable in terms of the mechanical strength and yield.

  4. Mitochondrial DNA analysis of Bronze Age horses recovered from Chifeng region, Inner Mongolia, China

    Institute of Scientific and Technical Information of China (English)

    Cai Dawei; Han Lu; Xie Chengzhi; Li Shengnan; Zhou Hui; Zhu Hong

    2007-01-01

    In this study, mitochondrial DNA (mtDNA) analysis was carried out on 9 Bronze Age horses recovered from Dashanqian and Jinggouzi archaeological sites in Chifeng region, Inner Mongolia, China to explore the origin of Chinese domestic horses. Both mtDNA 16S rRNA gene and control region (D-loop) fragments of ancient horses were amplified and sequenced. The analysis of the highly conservative 16S rRNA gene sequences indicated that the burial environment of Chifeng region is suitable for the preservation of ancient DNA (aDNA). Combing 465 mtDNA D-loop sequences representing different breeds from East Asia, Central Asia, Near East and Europe, we constructed a phylogenetic network to investigate the relationship between ancient and modern horses. The phylogenetic network showed that the 9 horses were distributed into different modem horse clusters which were closely related to them representing a certain ge-ographical distribution. Our results showed that the maternal genetic line of the ancient horses in Chifeng region was highly diversified,which contributed to the gene pool of modern domestic horses and suggested a complex origin of domestic horses in China.

  5. A family of rare earth molybdenum bronzes: Oxides consisting of periodic arrays of interacting magnetic units

    Science.gov (United States)

    Schneemeyer, L. F.; Siegrist, T.; Besara, T.; Lundberg, M.; Sun, J.; Singh, D. J.

    2015-07-01

    The family of rare earth molybdenum bronzes, reduced ternary molybdates of composition LnMo16O44, was synthesized and a detailed structural study carried out. Bond valence sum (BVS) calculations clearly show that the molybdenum ions in tetrahedral coordination are hexavalent while the electron count in the primitive unit cell is odd. Yet, measurements show that the phases are semiconductors. The temperature dependence of the magnetic susceptibility of samples containing several different rare earth elements was measured. These measurements verified the presence of a 6.5 K magnetic phase transition not arising from the rare earth constituent, but likely associated with the unique isolated ReO3-type Mo8O36 structural subunits in this phase. To better understand the behavior of these materials, electronic structure calculations were performed within density functional theory. Results suggest a magnetic state in which these structural moieties have an internal ferromagnetic arrangement, with small ~1/8 μB moments on each Mo. We suggest that the Mo8O36 units behave like pseudoatoms with spin 1/2 derived from a single hole distributed over the eight Mo atoms that are strongly hybridized with the O atoms of the subunit. Interestingly, while the compound is antiferromagnetic, our calculations suggest that a field-stabilized ferromagnetic state, if achievable, will be a narrow band half-metal.

  6. Origin of ferroelectric polarization in tetragonal tungsten-bronze-type oxides

    Science.gov (United States)

    Olsen, Gerhard Henning; Aschauer, Ulrich; Spaldin, Nicola A.; Selbach, Sverre Magnus; Grande, Tor

    2016-05-01

    The origin of ferroelectric polarization in tetragonal tungsten-bronze- (TTB-) type oxide strontium barium niobate (SBN) is investigated using first-principles density functional calculations. We study in particular the relationship between the polarization and the cation and vacancy ordering on alkali-earth metal lattice sites. Lattice dynamical calculations for paraelectric structures demonstrate that all cation configurations that can be accommodated in a 1 ×1 ×2 supercell result in a single unstable polar phonon, composed primarily of relative Nb-O displacements along the polar axis, as their dominant instability. The majority of the configurations also have a second octahedral tilt-mode instability which couples weakly to the polar mode. The existence of the tilt mode is strongly dependent on the local cation ordering, consistent with the fact that it is not found experimentally. Our results suggest that ferroelectricity in the SBN system is driven by a conventional second-order Jahn-Teller mechanism caused by the d0 Nb5 + cations, and demonstrate the strong influence of the size of Sr and Ba on the lattice distortions associated with polarization and octahedral tilting. Finally, we suggest a mechanism for the relaxor behavior in Sr-rich SBN based on Sr displacement inside pentagonal channels in the TTB structure.

  7. Microstructure and properties of an ordered and a disordered ship propeller bronze

    Energy Technology Data Exchange (ETDEWEB)

    Benkisser, G.; Winkel, G. [Rostock Univ. (Germany); Eberlein, J.; Kaps, R. [Mecklenburger Metallguss Waren (Germany)

    2000-07-01

    The purpose of this paper is a presentation of the investigation results on the influence of the chemical composition and the casting conditions on the transformation behaviour, the microstructure and the properties of the complex aluminium bronzes. By the solidification of the melt is produced the bcc high temperature phase {beta}. In dependence on the cooling time the {beta} - phase transforms in several product phases. In the ordered alloy additionally occur an ordering transformation of the {beta} - phase. Both alloys investigated posses in the sand cast state a heterogenous, coarse grained microstructure. The predominant part of the microstructure is the fcc {alpha} - phase. The lamellar quasieutectoid ({alpha} + {kappa}{sub 3}) and several types of {kappa} - segregates are further parts in the microstructure of the ordered alloy. The {gamma}{sub 2} - phase appears not in the microstructure. In the microstructure of the disordered alloy the retained bcc {beta} - phase and also {kappa} - segregates additionaly exist. The mechanical properties of the alloys depend on the chemical composition and the processing, especially on the cast wall thickness, because the thickness determines the cooling time and in connection with it the transformation behaviour and the phase composition, the grain size and the form and distribution of the phases in the microstructure. The ordered alloy has a higher cavitation resistance in comparison to the disordered alloy. (orig.)

  8. Genetic evidence for an origin of the Armenians from Bronze Age mixing of multiple populations.

    Science.gov (United States)

    Haber, Marc; Mezzavilla, Massimo; Xue, Yali; Comas, David; Gasparini, Paolo; Zalloua, Pierre; Tyler-Smith, Chris

    2016-06-01

    The Armenians are a culturally isolated population who historically inhabited a region in the Near East bounded by the Mediterranean and Black seas and the Caucasus, but remain under-represented in genetic studies and have a complex history including a major geographic displacement during World War I. Here, we analyse genome-wide variation in 173 Armenians and compare them with 78 other worldwide populations. We find that Armenians form a distinctive cluster linking the Near East, Europe, and the Caucasus. We show that Armenian diversity can be explained by several mixtures of Eurasian populations that occurred between ~3000 and ~2000 bce, a period characterized by major population migrations after the domestication of the horse, appearance of chariots, and the rise of advanced civilizations in the Near East. However, genetic signals of population mixture cease after ~1200 bce when Bronze Age civilizations in the Eastern Mediterranean world suddenly and violently collapsed. Armenians have since remained isolated and genetic structure within the population developed ~500 years ago when Armenia was divided between the Ottomans and the Safavid Empire in Iran. Finally, we show that Armenians have higher genetic affinity to Neolithic Europeans than other present-day Near Easterners, and that 29% of Armenian ancestry may originate from an ancestral population that is best represented by Neolithic Europeans. PMID:26486470

  9. Computed tomography of a medium size Roman bronze statue of Cupid

    Science.gov (United States)

    Bettuzzi, M.; Casali, F.; Morigi, M. P.; Brancaccio, R.; Carson, D.; Chiari, G.; Maish, J.

    2015-03-01

    Diagnostics based on X-ray computed tomography (CT) are becoming increasingly important, not only in the medical field but in industry and cultural heritage. CT devices typical for medical applications, however, can seldom be used on art objects because both they are not easily transportable and they often present high X-ray absorption. It is therefore necessary to make use of portable instrumentation and/or to develop tomographic systems optimized to the characteristics of the objects under examination. This work describes the computed tomography of a first century A.D. Roman bronze statue of Cupid (96.AB.53) in the collection of the J. Paul Getty Museum, within the collaborative framework between the Getty Conservation Institute and the Department of Physics and Astronomy (DIFA) of the University of Bologna (Italy). The tomography performed at the Getty facilities employed a 450 kV X-ray tube and a detection system developed at DIFA. The study highlighted the casting and construction techniques used by Roman foundry workers and provided information on the status of conservation of the statue. A 3D virtual reconstruction allowed the user to define different cross-sections enabling the study of the internal features.

  10. Gamma-radiography of the bronze door of the royal cathedral at Gniezno

    International Nuclear Information System (INIS)

    A knowledge of the technology of historical objects is important for a knowledge of the history of technique. There is in Poland a very interesting object: the door of the cathedral at Gniezno, cast in bronze in the 12th century. This door is composed of two wings which are different as to the character of the bas-reliefs, the dimensions, and the technology. On the front of each half there are nine panels with sculptured figures. The nine scenes on each wing are surrounded by an ornamental belt decorated by ledges. An investigation of the medieval technology of such an impressive casting was interesting both from the point of view of the history of art and the history of casting. In this case, the object was to find out whether the cast had been made in one piece or in parts and also how the liquid metal had been conveyed to the casting mould. In addition, radiologists were interested in the degree to which radiographic investigations can solve such problems. In order to obtain radiographs of the whole door it was necessary to make gammaradiographs. About a hunched radiographs were made, using the isotope Cs137. (author)

  11. Canine transposition in prehistoric Pakistan: Bronze Age and Iron Age case reports.

    Science.gov (United States)

    Lukacs, J R

    1998-10-01

    This report documents two prehistoric cases of canine-first premolar transposition (Mx.C.P1) from the Indo-Pakistan subcontinent. Recent discussion of the etiology of canine transposition and reports of high prevalence for the condition in modern India accentuate the significance of the ancient cases reported there. Case 1 is from the Iron Age site of Sarai Khola in northern Pakistan (1000 BC). The specimen, an adult female, 25 to 30 years of age at death, exhibits unilateral Mx.C.P1 transposition on the left side. The condition is associated with a barrel-shaped maxillary left third molar in an otherwise normal and healthy maxillary dental arch. Case 2 is from the Bronze Age urban site of Harappa (2500 BC), an important center of the Indus Valley Civilization. In this specimen, an adult female, transposition is bilateral, resulting in displacement of premolars and large diastemata between the maxillary lateral incisors and first premolars. Bilateral agenesis of maxillary third molars and rotation of maxillary and mandibular teeth occur with transposition in this specimen. In neither case are the lateral incisors reduced in size, peg-shaped, or congenitally absent. This report of Mx.C.P1 transposition in prehistoric times is significant because it provides historical documentation for the female predilection of the trait and establishes its co-occurrence with specific dental variants, such as agenesis, reduction, and rotation of teeth. PMID:9770107

  12. Dental paleopathology and agricultural intensification in south Asia: new evidence from Bronze Age Harappa.

    Science.gov (United States)

    Lukacs, J R

    1992-02-01

    Patterns of dental disease among Bronze Age people of the Indus Valley Civilization are currently based on early and incomplete reports by non-specialists. This deficiency precludes accurate diachronic analysis of dental disease and its relationship with increasing agriculturalism in the Indian subcontinent. The objective of this paper is to document prevalence of dental disease at Harappa (2500-2000 B.C.), Punjab Province, Pakistan, comparatively evaluate the Harappan dental pathology profile, and use these data to assess theories regarding the dental health consequences of increasingly intensive agricultural dependence. Pathological conditions of the dentition included in the study are abscesses, ante-mortem tooth loss (AMTL), calculus, caries, hypoplasia, hypercementosis, pulp chamber exposure, and alveolar resorption. The Harappan dentition exhibits a dental pathology profile typical of a population whose subsistence base is agriculture. Dental caries at Harappa are present in 6.8% (n = 751) of the teeth and 43.6% (n = 39) of the more completely preserved dental specimens. The use of a caries correction factor is recommended to permit an estimate of caries induced AMTL in calculating the caries prevalence. All dental lesions are present at higher rates in this Harappan study sample than were reported in previous investigations, and important differences in prevalence of dental disease occur between the genders. Prevalence of dental disease increases in the greater Indus Valley as subsistence becomes more intensive and as food preparation and storage technology becomes more efficient. PMID:1543240

  13. Phase transition and conduction mechanism of rare earth based tungsten-bronze compounds

    International Nuclear Information System (INIS)

    Highlights: ► The materials have very good ferroelectric properties for memory devices. ► The material has very good pyroelectric properties for detector application. ► Also these materials behave very good semiconducting properties. - Abstract: The polycrystalline materials (Li2Pb2R2W2Ti4Nb4O30 (R = Y, Eu)) of tungsten-bronze structural family have been synthesized using a high-temperature solid-state reaction (mixed-oxide) technique. The formation of the single phase compounds was checked using preliminary X-ray structural data/pattern. The nature and distribution of grains in the samples in the scanning electron micrographs (SEM) confirm the good quality of the samples used for electrical characterization. The phase transition (ferroelectric–paraelectric) in the materials was established through the detailed studies of dielectric, electric polarization and pyro-electric properties. Studies of pyroelectric properties show that the materials have reasonably high figure of merit useful for pyroelectric detector. The nature of frequency dependence of ac conductivity suggests that the materials obey Jonscher’s universal power law.

  14. The examination, analysis and conservation of a bronze Egyptian Horus statuette

    International Nuclear Information System (INIS)

    The production techniques, corrosive deterioration, conservation and questions regarding authenticity of a small Egyptian bronze statuette of the Child Horus (in the collection of the Ditsong: National Museum of Cultural History in Pretoria) was scientifically examined and analysed. The statuette dates to Egypt's 12th Dynasty. When the statuette was damaged, it was considered the appropriate time to obtain valuable information about its history and background through scientific research. Neutron tomography (NT), a relatively new non-destructive technique (NDT) to the South African R and D community to study museum objects, was applied to perform this research. The results from NT were supported by additional tests done through XRF and XRD analyses of samples taken from the damaged statuette. Results revealed that the lost-wax method was used in the manufacturing process. The extent of the restoration and materials used can be verified and as a result the deterioration of the object can now be monitored. This paper describes in detail the analytical techniques used in the study and how it contributed to the conservation of the statuette and its authenticity.

  15. Release of copper from sintered tungsten-bronze shot under different pH conditions and its potential toxicity to aquatic organisms

    International Nuclear Information System (INIS)

    Sintered tungsten-bronze is a new substitute for lead shot, and is about to be deposited in and around the wetlands of North America. This material contains copper in the alloyed form of bronze. This in vitro study was performed according to U.S. Fish and Wildlife Service criteria to determine the dissolution rate of copper from the shot, and to assess the toxic risk that it may present to aquatic organisms. The dissolution of copper from tungsten-bronze shot, pure copper shot, and glass beads was measured in a buffered, moderately hard, synthetic water of pH 5.5, 6.6, and 7.8 over a 28-day period. The dissolution of copper from both the control copper shot and the tungsten-bronze shot was affected significantly by the pH of the water and the duration of dissolution (all p values < 0.000). The rate of copper release from tungsten bronze shot was 30 to 50 times lower than that from the copper shot, depending on pH (p < 0.0000). The observed expected environmental concentration of copper released from tungsten-bronze shot after 28 days was 0.02 μg/L at pH 7.8, and 0.4 μg/L at pH 5.6, using a loading and exposure scenario specific in a U.S. Fish and Wildlife Service protocol. Ratio Quotient values derived from the highest EEC observed in this study (0.4 μg/L), and the copper toxic effect levels for all aquatic species listed in the U.S. Environmental Protection Agency ambient water quality criteria database, were all far less than the 0.1 criterion value. Given the conditions stipulated by the U.S. Fish and Wildlife Service and the U.S. Environmental Protection Agency, heavy loading from discharged tungsten-bronze shot would not pose a toxic risk to potable water, or to soil. Consequently, it would appear that no toxic risks to aquatic organisms will attend the use of tungsten-bronze shot of the approved composition. Given the likelihood that sintered tungsten-bronze of the same formula will be used for fishing weights, bullets, and wheel balance weights, it is

  16. The effect of low-dose neutron irradiation on mechanical properties, electrical resistivity and fracture of NiAl bronze for ITER

    International Nuclear Information System (INIS)

    Nickel-aluminum bronze is a candidate material for several applications for ITER in-vessel components such as divertor and blanket attachments and remote handling equipment. This paper presents the first results of an experimental investigation of the effect of neutron irradiation on mechanical properties, fracture characteristics and electrical resistivity of NiAl bronze. Specimens of NiAl bronze were irradiated at 150 oC and 300 oC to doses of 10-3; 10-2; 0.7 * 10-1 dpa in the RBT-6 reactor (Φt therm/Φt fast ∼ 1) in Dimitrovgrad. It was shown that irradiation at 150 oC leads to minor changes of tensile properties, whereas irradiation at 300 oC results in significant loss of ductility at damage dose of 0.07 dpa. The change of electrical resistively of NiAl bronze is low, ∼3% at the maximum dose studied. The reasons for the high-radiation resistance of NiAl bronze in comparison with copper and copper alloys are discussed

  17. 古滇王国青铜器的造型艺术研究%Research on Bronze Aesthetic Art of the Ancient Dian Kinadom

    Institute of Scientific and Technical Information of China (English)

    张吉洪

    2012-01-01

    Bronze art from the Ancient Dian Kingdom of Yunnan is an especially charming segment of China' s ancient bronze culture. Ancient Dian bronze art is famous for its outstanding aesthetics and intricate details. The firm conceptualization and practicality underpinning its stunning appearance has put it in a class of its own. The Ancient Dian had rendered numerous aspects of their civilization' s culture on bronze art -- farming, livestock, textiles, hunting and war, among others. They have created their animated history on bronze.%云南古滇青铜器的艺术魅力,是中华民族古代青铜文化中的一支夺目的奇葩,以其造型精美奇特、纹饰细腻丰富闻名于世,其写实性之强,构思巧妙,独树一帜。滇国的先民们把当时耕作、畜牧、纺织、狩猎、战争等各种社会生活场景凝聚在青铜器上,用自己的双手铸造了一部生动的青铜史诗。

  18. Dimensoes da vulnerabilidade para as familias da crianca com dor oncologica em ambiente hospitalar

    Directory of Open Access Journals (Sweden)

    Maria da Graca Corso da Motta

    2013-09-01

    Full Text Available Identificar aspectos que demonstrem as dimensões da vulnerabilidade no universo familiar na ótica da família de crianças com dor oncológica em ambiente hospitalar Trata-se de um estudo descritivo exploratório com abordagem qualitativa, realizada na Unidade de Hematologia e Oncologia Pediátrica, de um hospital de grande porte da cidade de Porto Alegre - RS. Participaram do estudo nove famílias, utilizando-se para coleta dos dados o Método Criativo Sensível, por meio das dinâmicas de criatividade e sensibilidade, analisadas conforme o referencial da Análise de Conteúdo de Minayo, nos meses de Maio e Junho de 2010 Constatou-se que a doença traz à tona situações de vulnerabilidade, conferindo à criança e à família, sofrimento, dor, medo, angústia, desgaste físico e mental, causados pelo câncer. Assim, a Enfermagem, ao apropriar-se do marco conceitual da vulnerabilidade, pode visualizar novas dimensões do processo saúde/doença auxiliando a criança doente e sua família.

  19. William R.Johnson,Board Chairman and CEO of HJ.Heinz Company has won the Marco Polo Award 2006

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Thanks to the contribution in promoting the talents visit and trade communication between America and China,William R.Johnson,Board Chairman and CEO of H.J.Heinz Company has won the Marco Polo Award.Zhang Jianguo,Vice President of China Foreign Experts Bureau granted the award to him.

  20. Marco Orientador del Ordenamiento Territorial Sustentable – Subsistema de Asentamientos Humanos (mapa Región Metropolitana de Santiago)

    OpenAIRE

    CONTRERAS-ALONSO, Miguel; Opazo, Daniel; UBILLA-BRAVO, Gerardo; Cecilia Núñez-Pino; Oliva-Mellado, Roberto; Hermosilla-Rumié, Vladimir; Saa-Vidal, René

    2004-01-01

    Mapa del Subsistema de Asentamientos Humanos del Marco Orientador del Ordenamiento Territorial (MOT) del Proyecto "Ordenamiento Territorial Ambientalmente Sustentable" (OTAS). El área corresponde a la Región Metropolitana de Santiago y su escala geográfica es 1:250.000.

  1. Marco Orientador del Ordenamiento Territorial Sustentable – Subsistema Socioproductivo (mapa Región Metropolitana de Santiago)

    OpenAIRE

    CONTRERAS-ALONSO, Miguel; UBILLA-BRAVO, Gerardo; Opazo, Daniel; NÚÑEZ-PINO, Cecilia; Oliva-Mellado, Roberto; Hermosilla-Rumié, Vladimir; Saa-Vidal, René

    2004-01-01

    Mapa del Subsistema Socioproductivo del Marco Orientador del Ordenamiento Territorial (MOT) del Proyecto "Ordenamiento Territorial Ambientalmente Sustentable" (OTAS). El área corresponde a la Región Metropolitana de Santiago y su escala geográfica es 1:250.000.

  2. Marco Orientador del Ordenamiento Territorial Sustentable – Subsistema Físico Ambiental (mapa Región Metropolitana de Santiago)

    OpenAIRE

    CONTRERAS-ALONSO, Miguel; UBILLA-BRAVO, Gerardo; Opazo, Daniel; NÚÑEZ-PINO, Cecilia; Oliva-Mellado, Roberto; Hermosilla-Rumié, Vladimir; Saa-Vidal, René

    2004-01-01

    Mapa del Subsistema Físico Ambiental del Marco Orientador del Ordenamiento Territorial (MOT) del Proyecto "Ordenamiento Territorial Ambientalmente Sustentable" (OTAS). El área corresponde a la Región Metropolitana de Santiago y su escala geográfica es 1:250.000.

  3. Un marco de referencia de cinco dimensiones para la evaluación auténtica

    NARCIS (Netherlands)

    Gulikers, Judith; Bastiaens, Theo; Kirschner, Paul A.

    2011-01-01

    Gulikers, J. T. M., Bastiaens, Th. J., & Kirschner, P. A. (2010). Un marco de referencia de cinco dimensiones para la evaluación auténtica. (translation from English). Cuajimalpa, México: Aseguramiento de la Calidad en la Educacion y en el Trabajo.

  4. Kaasaegse Kunsti Eesti Keskus kui kunstidiiler / Rael Artel, Kai Kaljo, Marco Laimre, Marge Monko ; intervjueerinud Reet Varblane

    Index Scriptorium Estoniae

    2010-01-01

    23. augustini 2010 saab KKEK juhataja kohale kandideerida. Vestlusringis osalenud vabakutseline kuraator Rael Artel, Tallinna Ülikooli dotsent, kunstnik Kai Kaljo, EKA fotoosakonna professor, kunstnik Marco Laimre ja EKA fotoosakonna dotsent, kunstnik Marge Monko arutavad, millist rolli peaks KKEK täitma praegu, 21. sajandi teisel kümnendil avatud maailma tingimustes

  5. Implicaciones del marco teórico de lo imaginario en la Psicología Social

    Directory of Open Access Journals (Sweden)

    Teresa Aracena Vicente

    2015-03-01

    Full Text Available En el presente estudio abordaremos dos de las principales concepciones sobre los mecanismos implicados en la construcción significativa del mundo. Hablamos de la Teoría de las Representaciones Sociales (TRS, formulada desde la psicología, y del marco teórico de lo imaginario, formulado principalmente desde la antropología y la filosofía. Procederemos exponiendo, primero, la TRS y, posteriormente, los acercamientos al marco teórico de lo imaginario desde diferentes disciplinas, para señalar las aportaciones que ofrece este último a la psicología social, aportaciones éstas que complementan las de la TRS. Así, este estudio tiene como objetivos realizar un análisis teórico de la TRS y del marco teórico de lo imaginario y especificar las contribuciones e implicaciones del marco teórico de lo imaginario a la psicología social (y, más concretamente, a la psicología cultural de modo a observar cómo el concepto de imaginario social incluye y trasciende al de representación social(RS. Consideraremos las implicaciones ontológicas, epistemológicas, metodológicas y para la salud de la utilización del marco teórico de lo imaginario en la psicología cultural. En este sentido, propondremos la adopción de dicho concepto por la psicología, considerando que el mismo es fundamental por su capacidad explicativa, comprensiva, interpretativa y crítica.

  6. Marcos da história da radioatividade e tendências atuais Landmarks in the history of radioactivity and current tendencies

    OpenAIRE

    Allan Moreira Xavier; André Gomes de Lima; Camila Rosa Moraes Vigna; Fabíola Manhas Verbi; Gisele Gonçalves Bortoleto; Karen Goraieb; Carol Hollingworth Collins; Maria Izabel Maretti Silveira Bueno

    2007-01-01

    The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medi...

  7. Marcos da história da radioatividade e tendências atuais Landmarks in the history of radioactivity and current tendencies

    Directory of Open Access Journals (Sweden)

    Allan Moreira Xavier

    2007-02-01

    Full Text Available The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medicinal, industrial and food applications of ionizing radiation. The text leads the reader to reflect on the subject and to consider its various aspects with scientific and technological maturity.

  8. El plan de regionalización del Estado de Bahia (Brasil): “Los Territorios de Identidad" como marco de aplicación de políticas públicas de fomento del desarrollo regional y de lucha contra la desigualdad (2007-2012)

    OpenAIRE

    Blatt, Nadir

    2014-01-01

    A presente tese doutoral teve como objetivo investigar os critérios que levaram o Governo do Estado da Bahia (Brasil) a definir no seu Planejamento Territorial, 27 Territórios de Identidade, incluídos os 417 municípios, utilizando-os como elementos constitutivos para a formulação de políticas públicas, voltadas para o desenvolvimento local e regional. Os Territórios de Identidade foram criados mediante Decreto nº 12.354, de 25.08.2010, constituindo-os como marco territorial de aplicação para ...

  9. Agricultural production and stability of settlement systems in Upper Mesopotamia during the Early Bronze Age (third millennium BCE)

    Science.gov (United States)

    Kalayci, Tuna

    This study investigates the relationship between rainfall variation and rain-fed agricultural production in Upper Mesopotamia with a specific focus on Early Bronze Age urban settlements. In return, the variation in production is used to explore stability of urban settlement systems. The organization of the flow of agricultural goods is the key to sustaining the total settlement system. The vulnerability of a settlement system increases due to the increased demand for more output from agricultural lands. This demand is the key for the success of urbanization project. However, without estimating how many foodstuffs were available at the end of a production cycle, further discussions on the forces that shaped and sustained urban settlement systems will be lacking. While large scale fluctuations in the flow of agricultural products between settlements are not the only determinants of hierarchical structures, the total available agricultural yield for each urban settlement in a hierarchy must have influenced settlement relations. As for the methodology, first, Early Bronze Age precipitation levels are estimated by using modern day associations between the eastern Mediterranean coastal areas and the inner regions of Upper Mesopotamia. Next, these levels are integrated into a remote-sensing based biological growth model. Also, a CORONA satellite imagery based archaeological survey is conducted in order to map the Early Bronze Age settlement system in its entirety as well as the ancient markers of agricultural intensification. Finally, ancient agricultural production landscapes are modeled in a GIS. The study takes a critical position towards the traditionally held assumption that large urban settlements (cities) in Upper Mesopotamia were in a state of constant demand for food. The results from this study also suggest that when variations in ancient precipitation levels are translated into the variations in production levels, the impact of climatic aridification on ancient

  10. The influence of the chemical composition and temperature of plastic deformation on the PLC effect in tin bronzes

    Directory of Open Access Journals (Sweden)

    W. Ozgowicz

    2006-04-01

    Full Text Available Purpose: The aim of the present paper is the determination of the effect of the chemical composition and temperature of deformation of standardized tin bronzes and bronze modified with zirconium on the Portevin – Le Chatelier (PLC phenomenon, mainly basing on the shape of stress-strain curves within the temperature range of 100÷300oC and observations of their structure. The reasons of the occurrence of such en effect are so far no fully known and explained and the opinions concerning is physical basis vary.Design/methodology/approach: Of essential design in this research is determination of the dependence of PLC effect on the chemical composition, temperature and strain rate and the preliminary heat treatment and grain size. The main method used in this investigation is tensile test at elevated temperature.Findings: The main conclusions are following: the PLC effect on tin bronzes with a miero-addition of zirconium in an amount of 0.01÷0.05% depends the temperature of deformation in the tensile test in the range of 100÷300°C and the chemical composition of the alloys; the type of serration revealed on the δ–ε curve depend mainly on the temperature of deformation and can be differ during the respective stages of the analyzed curves.Practical implications: In this paper implications for practice are not taken into consideration.Originality/value: In this paper an additive type of serration observed on the curves δ–ε, denoted by the symbol D, is new.

  11. High-energy electron-energy-loss study of sodium-tungsten bronzes

    International Nuclear Information System (INIS)

    Single-crystal metallic cubic sodium-tungsten bronzes NaxWO3 (x≥0.25) and NaxTayW1-yO3 (x-y=0.42) and monoclinic reduced WO3-δ have been investigated by high-energy electron-energy-loss spectroscopy (EELS) in transmission. For all electron densities the volume plasmon dispersion appears to be positive quadratic in momentum transfer q. The dispersion coefficient is much smaller than that predicted from the random-phase approximation for one isotropic parabolic band. This deviation can be reduced by recognizing the threefold degeneracy of the conduction-band t2g states in an octahedral field and narrowing of these bands with increasing sodium content. Anisotropy of the dispersion between the (100) and (110) direction is not observed. Optical effective masses m*(x) of the conduction electrons and background dielectric constants ε∞(x) have been determined and compare well with data from optical spectroscopy and EELS in reflection, but not with photoemission results. This discrepancy is a result of the photoemission-data evaluation in which the conduction-band degeneracy was neglected. Na 2p core-level excitation energies argue against an admixture of sodium orbitals to the conduction band near the metal-nonmetal transition at x∼0.2. Na 3s states admixed to O 2p states are observed at about 10--11 eV above the Fermi level in O 1s absorption edges. The x dependence of m* and of the width of the O 1s absorption edge of NaxWO3 supports a model of conduction-band narrowing with increasing Na concentration

  12. Fish remnants from the excavations of the Bronze Age barrow near Maryanskoe village (Dnepropetrovsk region, Ukraine

    Directory of Open Access Journals (Sweden)

    O. M. Kovalchuk

    2014-10-01

    Full Text Available The Bronze Age mound (2.5–2.3 kya BC is located near the Maryanskoe village (Apostolovskyi district, Dnepropetrovsk region and was excavated in 1953. The results of determination of the fish remnants, which were found during the excavation, are presented in the paper. Eleven species belonging to 9 genera, 5 families and 5 orders (Acipenseriformes, Cypriniformes, Siluriformes, Esociformes, Perciformes were identified: russian sturgeon Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833, stellate sturgeon A. stellatus Pallas, 1771, common ide Idus idus (Linnaeus, 1758, common roach Rutilus rutilus (Linnaeus, 1758, pontic roach R. frisii (Nordmann, 1840, common bream Abramis brama (Linnaeus, 1758, common carp Cyprinus carpio Linnaeus, 1758, tench Tinca tinca (Linnaeus, 1758, european catfish Silurus glanis Linnaeus, 1758, northern pike Esox lucius (Linnaeus, 1758, and zander Sander lucioperca (Linnaeus, 1758. Most of them are quite common in the Dnieper river basin. It was found that carp fishes predominate in the number of species. Most of the bone remnants in the collection belong to zander, catfish and pike, while common roach, pontic roach and common bream are identified by the few bones. This may indicate a different role of these species in the diet of the local population. The ratio of skeletal elements in the collection is the evidence of the fish cutting on the site. Body length and weight was reconstructed for 64 fish specimens. It was found that they were mature and small-sized, except for catfish, pike and perch. Taking into account the characteristics of the funeral rituals of the Yamna culture population, fish bones from the mound near Maryanskoe can be remnants of the parting meal.

  13. Characterizing a Middle Bronze palatial wine cellar from Tel Kabri, Israel.

    Science.gov (United States)

    Koh, Andrew J; Yasur-Landau, Assaf; Cline, Eric H

    2014-01-01

    Scholars have for generations recognized the importance of wine production, distribution, and consumption in relation to second millennium BC palatial complexes in the Mediterranean and Near East. However, direct archaeological evidence has rarely been offered, despite the prominence of ancient viticulture in administrative clay tablets, visual media, and various forms of documentation. Tartaric and syringic acids, along with evidence for resination, have been identified in ancient ceramics, but until now the archaeological contexts behind these sporadic discoveries had been uneven and vague, precluding definitive conclusions about the nature of ancient viticulture. The situation has now changed. During the 2013 excavation season of the Kabri Archaeological Project, a rare opportunity materialized when forty large storage vessels were found in situ in an enclosed room located to the west of the central courtyard within the Middle Bronze Age Canaanite palace. A comprehensive program of organic residue analysis has now revealed that all of the relatively uniform jars contain evidence for wine. Furthermore, the enclosed context inherent to a singular intact wine cellar presented an unprecedented opportunity for a scientifically intensive study, allowing for the detection of subtle differences in the ingredients or additives within similar wine jars of apparently the same vintage. Additives seem to have included honey, storax resin, terebinth resin, cedar oil, cyperus, juniper, and perhaps even mint, myrtle, or cinnamon, all or most of which are attested in the 18th century BC Mari texts from Mesopotamia and the 15th century BC Ebers Papyrus from Egypt. These additives suggest a sophisticated understanding of the botanical landscape and the pharmacopeic skills necessary to produce a complex beverage that balanced preservation, palatability, and psychoactivity. This new study has resulted in insights unachievable in the past, which contribute to a greater understanding

  14. Characterizing a Middle Bronze palatial wine cellar from Tel Kabri, Israel.

    Directory of Open Access Journals (Sweden)

    Andrew J Koh

    Full Text Available Scholars have for generations recognized the importance of wine production, distribution, and consumption in relation to second millennium BC palatial complexes in the Mediterranean and Near East. However, direct archaeological evidence has rarely been offered, despite the prominence of ancient viticulture in administrative clay tablets, visual media, and various forms of documentation. Tartaric and syringic acids, along with evidence for resination, have been identified in ancient ceramics, but until now the archaeological contexts behind these sporadic discoveries had been uneven and vague, precluding definitive conclusions about the nature of ancient viticulture. The situation has now changed. During the 2013 excavation season of the Kabri Archaeological Project, a rare opportunity materialized when forty large storage vessels were found in situ in an enclosed room located to the west of the central courtyard within the Middle Bronze Age Canaanite palace. A comprehensive program of organic residue analysis has now revealed that all of the relatively uniform jars contain evidence for wine. Furthermore, the enclosed context inherent to a singular intact wine cellar presented an unprecedented opportunity for a scientifically intensive study, allowing for the detection of subtle differences in the ingredients or additives within similar wine jars of apparently the same vintage. Additives seem to have included honey, storax resin, terebinth resin, cedar oil, cyperus, juniper, and perhaps even mint, myrtle, or cinnamon, all or most of which are attested in the 18th century BC Mari texts from Mesopotamia and the 15th century BC Ebers Papyrus from Egypt. These additives suggest a sophisticated understanding of the botanical landscape and the pharmacopeic skills necessary to produce a complex beverage that balanced preservation, palatability, and psychoactivity. This new study has resulted in insights unachievable in the past, which contribute to a

  15. Ancient road transport devices: Developments from the Bronze Age to the Roman Empire

    Science.gov (United States)

    Rossi, Cesare; Chondros, Thomas G.; Milidonis, Kypros F.; Savino, Sergio; Russo, Flavio

    2016-03-01

    The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horsedrawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic Greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

  16. High-Rate Intercalation without Nanostructuring in Metastable Nb2O5 Bronze Phases.

    Science.gov (United States)

    Griffith, Kent J; Forse, Alexander C; Griffin, John M; Grey, Clare P

    2016-07-20

    Nanostructuring and nanosizing have been widely employed to increase the rate capability in a variety of energy storage materials. While nanoprocessing is required for many materials, we show here that both the capacity and rate performance of low-temperature bronze-phase TT- and T-polymorphs of Nb2O5 are inherent properties of the bulk crystal structure. Their unique "room-and-pillar" NbO6/NbO7 framework structure provides a stable host for lithium intercalation; bond valence sum mapping exposes the degenerate diffusion pathways in the sites (rooms) surrounding the oxygen pillars of this complex structure. Electrochemical analysis of thick films of micrometer-sized, insulating niobia particles indicates that the capacity of the T-phase, measured over a fixed potential window, is limited only by the Ohmic drop up to at least 60C (12.1 A·g(-1)), while the higher temperature (Wadsley-Roth, crystallographic shear structure) H-phase shows high intercalation capacity (>200 mA·h·g(-1)) but only at moderate rates. High-resolution (6/7)Li solid-state nuclear magnetic resonance (NMR) spectroscopy of T-Nb2O5 revealed two distinct spin reservoirs, a small initial rigid population and a majority-component mobile distribution of lithium. Variable-temperature NMR showed lithium dynamics for the majority lithium characterized by very low activation energies of 58(2)-98(1) meV. The fast rate, high density, good gravimetric capacity, excellent capacity retention, and safety features of bulk, insulating Nb2O5 synthesized in a single step at relatively low temperatures suggest that this material not only is structurally and electronically exceptional but merits consideration for a range of further applications. In addition, the realization of high rate performance without nanostructuring in a complex insulating oxide expands the field for battery material exploration beyond conventional strategies and structural motifs. PMID:27264849

  17. Cavitation Erosion Corrosion Behaviour of Manganese-nickel -aluminum Bronze in Comparison with Manganese-brass

    Institute of Scientific and Technical Information of China (English)

    Hong Yu; Yugui Zheng; Zhiming Yao

    2009-01-01

    The cavitation erosion corrosion behaviour of ZQMn 12-8-3-2 manganese-nickel-aluminum bronze and ZHMn55-3-1 manganese-brass was investigated by mass loss, electrochemical measurements (polarization curves and electrochemical impedance spectroscopy) and the cavitation damaged surfaces were observed by scanning electron microscopy (SEM). The results showed that ZQMn 12-8-3-2 had better cavitation erosion resistance than ZHMn55-3-l. After the cavitation erosion for 6 h, the cumulative mass loss of ZQMnl2-8-3-2 was about 1/3 that of ZHMn55-3-l. The corrosion current density of ZQMnl2-8-3-2 was less than that of ZHMn55-3-l under both static and cavitaiton condition. The free-corrosion potentials of ZQMnl2-8-3-2 and ZHMn55-3-l were all shifted in positive direction under cavitation condition compared to static condition. In the total cu-mulative mass loss under cavitation condition, the pure erosion played a key role for the two tested materials (74% for ZHMn55-3-l and 60% for ZQMnl2-8-3-2), and the total synergism between corrosion and erosion of ZQMnl2-8-3-2 (39%) was larger than that of ZHMn55-3-l (23%). The high cavitation erosion resistance of ZQMnl2-8-3-2 was mainly attributed to its lower stacking fault energy (SFE), the higher microhardness and work-hardening ability as well as the favorable propagation of cavitation cracks for ZQMn 12-8-3-2, i.e., parallel to the surface rather than perpendicular to the surface for ZHMn55-3-l.

  18. Archaeomagnetic Dating of Bronze Age Pottery in Syria: New Intensity Data for 2300 to 1000 BCE

    Science.gov (United States)

    Stillinger, M. D.; Feinberg, J. M.; Frahm, E.

    2013-12-01

    In order to construct meaningful site chronologies, Near Eastern archaeologists have traditionally relied on relative dating techniques, such as ceramic seriation and textual/glyptic evidence. The introduction of radiocarbon dating provided archaeologists with an absolute dating tool to address age discrepancies. However, many sites do not contain sufficient or suitable materials for radiocarbon analysis, requiring the need for an alternative absolute dating tool. Archaeomagnetic dating provides such an alternative. Excavations at Tell Mozan (Bronze-Age Urkesh) in northeastern Syria have revealed evidence for nearly 5000 years of occupation in strata containing a variety of diagnostic ceramic artifacts, which form the basis for a well-established relative site chronology. In order to test the agreement between seriation ages and paleomagnetic-derived ages, archaeointensity experiments were conducted on pottery specimens from six well-stratified occupational layers spanning more than a thousand years of the site's primary occupation. Archaeointensity was determined using the IZZI paleointensity protocol of Tauxe and Staudigel (2004), and all estimates were corrected for remanence anisotropy and cooling rate effects, resulting in an 88% success rate (n = 51). The magnetic mineral assemblage of each sample was also characterized using a comprehensive suite of rock magnetic techniques. Final results were compared with previous archaeointensity studies in the region, and 70% of the magnetically-derived ages agree with the archaeologically-derived dates within a 1σ confidence interval, while 76% agreed within 2σ. Artifacts showing disagreement with the seriation chronology are most likely objects in use long after their original firing or the result of contamination of strata from the re-use of previous occupational materials in construction. One specimen appears to confirm the presence of a geomagnetic spike around 1000 BCE previously identified in Syria, Israel

  19. Domain structures of sodium tungsten bronzes, Na/sub x/WO/sub 3/ (0. 4 < x < 1)

    Energy Technology Data Exchange (ETDEWEB)

    Atoji, M.

    1978-01-01

    Optical-microscope observations with polarized light have shown that the birefringent, twin-domain structure of sodium tungsten bronzes is exhibited by Na-deficient, epitaxial surface films and hence is not a bulk property as had been suggested elsewhere. The film is translucent, 10/sup -2/ - 10/sup -3/ mm thick or less, and often laminates to a multi-film layer. The domain boundaries are sensitive to lateral stress and, apparently, to minute changes in the substrate structure. These and related properties of the film and the substrate are presented.

  20. Metal-insulator transition in sodium tungsten bronzes, NaxWO3, studied by angle-resolved photoemission spectroscopy

    International Nuclear Information System (INIS)

    We report high-resolution angle-resolved photoemission spectroscopy on sodium tungsten bronzes, NaxWO3, which exhibit a metal-insulator transition as a function of x. We found that the near-EF states are localized in NaxWO3 (x=+ ions in the WO3 lattice, which makes the system insulating. In the metallic regime we found that the rigid shift of band structure can explain the metallic NaxWO3 band structure with respect to Na doping

  1. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat; Crepaz, Rudolf; Eggert, Torben; Bey, Niki

    2010-01-01

    compositions were tested. A test method that provides uniform test conditions is described. The method can be used as general test method to analyse off gasses from binders. Moulds containing a standard size casting were produced and the amount and type of organic compounds resulting from thermal degradation...... of binders was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gasses in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO...

  2. Experimental determination of stability margin in a 27 strand bronze matrix, Nb3Sn cable-in-conduit conductor

    International Nuclear Information System (INIS)

    A small coil of internally cooled cabled superconductor was fabricated for experimental determination of the stability margin. The conductor is 27 strands of Nb3Sn in a bronze matrix. The sheath material is JBK-75 superalloy. The bifilar coil was potted in epoxy in the annulus of a pulse coil set. Experimental results are presented defining critical pulse energy as a function of normalized operating current and background field. The relationships between dB/dt, pulse energy and stability margin are derived by calculation and confirmed by experimental calibration

  3. Micro-chemical and metallurgical study of Samnite bronze belts from ancient Abruzzo (central Italy, VIII-IV BC)

    Science.gov (United States)

    Riccucci, Cristina; Ingo, Gabriel Maria; Faustoferri, Amalia; Pierigè, Maria Isabella; Parisi, Erica Isabella; Di Carlo, Gabriella; De Caro, Tilde; Faraldi, Federica

    2013-12-01

    The Samnite bronze belts and the chest disk cuirasses (VIII-IV BC) are the distinctive defensive weapons of the Samnite warriors having likely also a symbolic relevance. These artefacts were mainly found during the archaeological excavations of warriors' graves from ancient Abruzzo (central Italy). Their chemical composition, metallurgical features and corrosion products formed during the long-term burial have been studied by means of the combined use of analytical techniques such as optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray micro-analysis (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The micro-chemical and structural results show that the bronze belts have often been produced by using unusual high-tin bronze alloys achieving a silver-like appearance and by performing tailored cycles of thermal treatments under reducing conditions and hot mechanical working aimed to shape the high-tin alloys in the form of a thin bronze sheet. Furthermore, the investigation has shown that the main alloying elements have been transformed during the burial into mineral species giving rise to the formation of stratified structures constituted by different mineral phases such as tin oxides, cuprous oxide (Cu2O) and copper carbonates (azurite (Cu3(CO3)2(OH)2 and malachite (CuCO3Cu(OH)2)) as well as dangerous chlorine-based compounds such as nantokite (CuCl) and atacamite (Cu2(OH)3Cl) polymorphs. This information evidences the strict interaction of the alloying elements with the soil components as well as the occurrence of the copper cyclic corrosion as a post-burial degradation phenomenon. The present study confirms that the combined micro-chemical and micro-structural investigation techniques such as SEM-EDS, XPS, XRD and OM can be successfully used to investigate the technological production processes of the ancient artefacts and to achieve the detailed micro-chemical and structural description of the

  4. Effect of microstructure on the mechanical and corrosion behaviors of a hot-extruded nickel aluminum bronze

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,the influence of microstructure on the corrosion behavior of a hotextruded nickel aluminum bronze was studied.Three kinds of samples subjected to the hot-extrusion,annealing and quenching conditions were prepared and immersion tests in 3.5% NaCl solution were carried out.Microstructures and corrosion surface morphologies of the samples were observed by SEM.It was found that the retained β martensite and(α+κⅢ) lamella eutectoid in the as hot-extruded material were eliminated after annealing,and...

  5. Microstructural transformations and mechanical properties of cast NiAl bronze: Effects of fusion welding and friction stir processing

    OpenAIRE

    Fuller, M D; Swaminathan, S.; Zhilyaev, A.P.; T.R. McNelley

    2007-01-01

    A plate of as-cast NiAl bronze (NAB) material was sectioned from a large casting. A six-pass fusion weld overlay was placed in a machined groove; a portion of the weld reinforcement was removed by milling and a single friction stir processing (FSP) pass was conducted in a direction transverse to the axis of and over the weld overlay. A procedure was developed for machining of miniature tensile samples and the distributions of strength and ductility were evaluated for the fusion weld metal;...

  6. CONTRIBUTIONS TO THE STUDY OF THE VIBRATIONS FREQUENCY OF THE DRILL TOOL IN THE PROCESS OF MANUFACTURING THE BRONZE MATERIALS

    Directory of Open Access Journals (Sweden)

    Cosmin-Mihai MIRIŢOIU

    2013-05-01

    Full Text Available In this paper we present the experimental testings used to study the vibration of the drill tool, during the drilling of the bronze products. We have used the experimental setup presented in Miriţoiu (2013[1]. In this paper the vibrations are analyzed during the drilling on the universal lathe machines. The main purpose of to find a correlation between the cutting speed and the frequency of the vibration by using the experimental results and the regression analysis

  7. Increasing Mobility at the Neolithic/Bronze Age Transition - sulphur isotope evidence from Öland, Sweden

    OpenAIRE

    Anna Linderholm; Elin Fornander; Gunilla Eriksson; Carl-Magnus Mörth; Kerstin Lidén

    2014-01-01

    The objective of this investigation is to look at the use of various aquatic, in this case marine, resources in relation to mobility during the Neolithic and Bronze Age periods. On the island of Öland, in the Baltic Sea, different archaeological cultures are represented in the form of material culture and skeletal remains at three sites. We have analysed δ34S values in human remains representing 36 individuals, as well as faunal remains. We investigated intra-individual patterns of mobility f...

  8. The crystal chemistry of the tetragonal tungsten-bronze: Ba6FeNb9O30

    International Nuclear Information System (INIS)

    Solid state reaction of BaCO3, FeC2O4 x 2 H2O and Nb2O5 gave single crystals of Ba6FeNb9O30. The crystal strucuture was solved by X-ray investigations (a = 12.597, c = 3.990 Ao, space group P4 bm - C4v2, Z = 1). Ba6FeNb9O30 crystallyzes in the tetragonal bronze type with a statistical distribution of Fe3+ and Nb5+ in the octahedral framework. The anisotropic temperature factors of barium are discussed with respect to the oxygen coordination. (Author)

  9. A report on the examination of animal skin artefacts from the Bronze Age salt mines of Hallstatt, Austria

    OpenAIRE

    Susanna Harris

    2006-01-01

    My PhD research focuses on the social context of cloth from the Neolithic to Bronze Age with case studies from the Alpine area. One aspect of this is the interrelationship of the technologies used to create flexible, thin sheets of material that can be wrapped, folded, shaped and tied. This includes fibre-based cloth such as textiles, netting and twining as well as animal skins (leather and fur). This short report summarises preliminary research findings stemming from the examination of anima...

  10. An investigation into the microstructure and mechanical properties of centrifugally and conventional castings of complex Al-bronzes

    International Nuclear Information System (INIS)

    Complex Al-bronzes are new range of materials in copper alloys, attracting the attention of design engineers for high strength, better toughness, high temperature and favorable tribological applications properties accomplished by different casting methods give a comparable study of physical, mechanical and microstructural characteristics. The presence of gamma phase has been significantly controlled by the rate of cooling. Successful attempts have been made to produce the beneficial microstructure by controlling the freezing range. This paper discusses the finding of investigations to produce desirable microstructures in the centrifugal and conventional sand moulds. (author)

  11. Behavior of the monophosphate tungsten bronzes (PO2)4(WO3)2m (m = 7 and 8) in the course of electrochemical lithium insertion

    International Nuclear Information System (INIS)

    The electrochemical lithium insertion process has been studied in the family of monophosphate tungsten bronzes (PO2)4(WO3)2m, where m = 7 and 8. Structural changes in the pristine oxides were followed as lithium insertion proceeded. Through potentiostatic intermittent technique the different processes which take place in the cathode during the discharge of the cell were analyzed. The nature of the bronzes Li x(PO2)4(WO3)2m formed was determined by in situ X-ray diffraction experiments. These results have allowed establishing a correlation with the reversible/irreversible processes detected during the electrochemical lithium insertion

  12. Methodology for the Construction of a Rule-Based Knowledge Base Enabling the Selection of Appropriate Bronze Heat Treatment Parameters Using Rough Sets

    Directory of Open Access Journals (Sweden)

    Górny Z.

    2015-04-01

    Full Text Available Decisions regarding appropriate methods for the heat treatment of bronzes affect the final properties obtained in these materials. This study gives an example of the construction of a knowledge base with application of the rough set theory. Using relevant inference mechanisms, knowledge stored in the rule-based database allows the selection of appropriate heat treatment parameters to achieve the required properties of bronze. The paper presents the methodology and the results of exploratory research. It also discloses the methodology used in the creation of a knowledge base.

  13. Tribolayer Formation on Bronze Cu Sn12Ni2 in the Tribological Contact between Cy linder and Cont rol Plate in an Axial Piston Pump with Swashplate Design

    OpenAIRE

    Paulus, Andreas; Jacobs, Georg

    2016-01-01

    The present study investigates the f ormation of tribolayers on bronze CuSn12Ni2. Two different test rigs are used, of which one is a sliding bearing test rig in order to perform lubricated thrust bearing tests. Bronze CuSn12Ni2 is used for the sliding elements and the counter body is made of C45 steel. In addition to that, an axial piston pump test rig was used to determine t he transfera bility of the results to th e axial pist on pump. The test conditions are set up in a way t hat the trib...

  14. European asteroid sample return mission: MarcoPolo-R and its future

    Science.gov (United States)

    Barucci, M.

    2014-07-01

    MarcoPolo-R is a sample return mission study to a primitive Near-Earth Asteroid (NEA) carried out at ESA from 2008 in the framework of ESA's Cosmic Vision (CV) programme, with the objective to answer to the fundamental CV questions ''How does the Solar System work?'' and ''What are the conditions for life and planetary formation?''. The returned material will allow us to study in terrestrial laboratories some of the most primitive materials available to investigate early solar system formation processes, to explore initial stages of habitable planet formation, to identify and characterize the organics and volatiles in a primitive asteroid. In fact, only in the laboratory can instruments with the necessary precision and sensitivity be applied to individual components of the complex mixture of materials that forms an asteroid regolith, to determine their precise chemical and isotopic composition. Such measurements are vital for revealing the evidence of interstellar medium, pre-solar nebula and parent body processes that are retained in primitive asteroidal material, unaltered by atmospheric entry or terrestrial contamination. In addition to addressing these major science goals, the MarcoPolo-R mission study (ESA/SRE (2013)4) also involved innovative European technologies for which ESA technical development programs are still under way. As a result of the several industrial studies, ESA designed a remarkably cost-effective and robust asteroid sample return mission scenario. The spacecraft has been defined making use of low-cost units for most of the sub-systems. The key sample return capabilities, i.e. asteroid navigation, touch and go, sampling mechanism and the re-entry capsule have reached at ESA a validation status to enter implementation phase. In this new era of international effort and interest of sample return with the selected missions of Hayabusa-2 (JAXA) and OSIRIS-Rex (NASA), the development of sample return technology represents in Europe a crucial

  15. Marco Benoît Carbone, Tentacle erotica. Orrore, seduzione, immaginari pornografici

    OpenAIRE

    Luca Zenobi

    2015-01-01

    “Mimesis Media/Eros. Sessualità, tecnologia, rappresentazioni” è la collana diretta da Giovanna Maina e Federico Zecca, due giovani studiosi che, assieme ad Enrico Biasin (Porno espanso, Mimesis, 2011, Porn after Porn, Mimesis International, 2014), hanno avuto il merito di “sdoganare” i porn studies in Italia e, soprattutto, di averlo fatto in una maniera tale da renderli un componente di primo livello del dibattito scientifico, grazie alla collaborazione con studiosi internazionali e a un at...

  16. Negociaci??n colectiva transnacional y redes transnacionales de producci??n : geograf??as de derechos sociales a trav??s de acuerdos marco transnacionales

    OpenAIRE

    Canalda Criado, Sergio

    2014-01-01

    Dentro de los debates sobre contexto y evoluci??n del Derecho del Trabajo, las nuevas formas de organizaci??n empresarial plantean un complejo marco de equilibrios de poder entre los actores a la hora gobernar las relaciones laborales. Los sistemas de producci??n transnacional en forma de red se integran en este marco de definici??n del Derecho del Trabajo en su vertiente colectiva.Los Acuerdos Marco Transnacionales, negociados entre las empresas multinacionales y los representantes de los tr...

  17. Marco jurídico de las cooperativas de trabajo asociado

    Directory of Open Access Journals (Sweden)

    Eraclio Arenas Gallego

    2007-05-01

    Full Text Available Este artículo presenta los resultados de la investigación institucional denominada: 'Las cooperativas de trabajo asociado y su impacto sobre los derechos mínimos laborales', realizada bajo la coyuntura que plantea la necesidad de flexibilizar las normas sobre el trabajo para otorgarle mayor competitividad al mercado nacional, frente a la indebida utilización de las diferentes figuras jurídicas de contratación de mano de obra, atada a la precarización de los derechos de los trabajadores. El auge de la flexibilización del derecho del trabajo en Colombia a través de la subcontratación de servicios por medio de las cooperativas de trabajo asociado (CTA ha generado bastante controversia en los últimos años. Consecuencia de lo anterior, el Gobierno Nacional reglamentó nuevamente su actividad por medio del decreto 4588 de 2006, con la finalidad de incrementar los niveles de eficacia en su vigilancia y control, haciéndose necesario analizar dicho marco regulatorio para así avizorar su futuro operativo y la eficacia de las medidas adoptadas para lograr un uso idóneo y transparente de dichas entidades.

  18. Marcos Zapata's "Last Supper": a feast of European religion and Andean culture.

    Science.gov (United States)

    Zendt, Christina

    2010-01-01

    In Marcos Zapata's 1753 painting of the Last Supper in Cuzco, Peru, Christian symbolism is filtered through Andean cultural tradition. Zapata was a late member of the Cuzco School of Painting, a group comprised of few European immigrants and handfuls of mestizo and Indian artists. The painters in Cuzco learned mostly from prints of European paintings, and their style tends to blend local culture into the traditional painting of their conquistadors. Imagery was the most successful tool used by the Spaniards in their quest to Christianize the Andean population. By teaching locals to paint Christian subjects, they were able to infuse Christianity into Andean traditions. Zapata's rendering of the Last Supper utilizes this cultural blending while staying true to the Christian symbolism within the subject. Instead of the traditional lamb, Zapata's Last Supper features a platter of cuy, or guinea pig, an Andean delicacy stocked with protein as well as cultural significance. Cuy was traditionally a sacrificial animal at Inca agricultural festivals and in this way it offers poignant parallel to the lamb, as a traditional Christian sacrificial animal. PMID:21568039

  19. ¿Es eficaz el terrorismo? Consideraciones, problemas y marco de investigación futura

    Directory of Open Access Journals (Sweden)

    Richard English

    2016-04-01

    Full Text Available La cuestión de «si es eficaz el terrorismo» es de vital importancia tanto desde el punto de vista práctico como intelectual; no obstante, ha sido ampliamente eclipsada por otras consideraciones desarrolladas dentro de la literatura académica sobre el terrorismo. En este contexto, el presente artículo aborda algunas de las aportaciones recientes al debate emergente relacionado con dicha cuestión; destaca varias de las problemáticas inherentes a la discusión académica con respecto a este tema surgidas hasta la fecha; y, por último, esboza un marco para que la investigación académica futura en esta área tenga un carácter más inclusivo, sistemático y fructífero en el plano dialógico que el que ha tenido hasta la fecha.

  20. La familia en el marco de la justicia transicional: retos y reconocimientos

    Directory of Open Access Journals (Sweden)

    José Fernando Valencia Grajales

    2016-07-01

    Full Text Available Dentro del marco del proceso de paz en Colombia existen una gran cantidad de interrogantes que afectan a la sociedad colombiana, sin embargo uno de los elementos que no han sido tenidos en cuenta de forma directa son los efectos producidos durante los últimos 60 años sobre la configuración de la familia, esta situación será estudiada dentro del proyecto de investigación “familia, victimas y justicia transicional”. Este texto intenta una revisión histórica-holística al concepto de Familia, sus cambios al cabo de la historia, por un lado, luego, compara la familia tradicional cristiana, su conflicto con el mundo moderno, su composición dentro de la modernidad para luego planear dicho concepto y concepción de cara al contexto de violencia política, social y armada que ha vivido Colombia, para cerrar con una reflexión en tono al cómo, estas configuraciones, afectan o no, los abordajes y desarrollos de la posible aplicación de la justicia transicional.