WorldWideScience

Sample records for te reo maori

  1. Ka Whanau mai te Reo: Honouring Whanau, Upholding Reo Maori

    Science.gov (United States)

    Bright, Nicola; Barnes, Alex; Hutchings, Jessica

    2013-01-01

    This is the first report from a 3-year (2012-2015) kaupapa Maori research project that investigates how best to support the continuity of reo Maori development of whanau as they transition between kohanga reo, kura kaupapa primary, wharekura, secondary and beyond. It aims to provide useful information about the reo Maori education options that are…

  2. Speech Language Assessments in Te Reo in a Primary School Maori Immersion Unit

    Science.gov (United States)

    Naidoo, Kershni

    2012-01-01

    This research originated from the need for a speech and language therapy assessment in te reo Maori for a particular child who attended a Maori immersion unit. A Speech and Language Therapy te reo assessment had already been developed but it needed to be revised and normative data collected. Discussions and assessments were carried out in a…

  3. Te Reo Maori: Indigenous Language Acquisition in the Context of New Zealand English

    Science.gov (United States)

    Reese, Elaine; Keegan, Peter; McNaughton, Stuart; Kingi, Te Kani; Carr, Polly Atatoa; Schmidt, Johanna; Mohal, Jatender; Grant, Cameron; Morton, Susan

    2018-01-01

    This study assessed the status of te reo Maori, the indigenous language of New Zealand, in the context of New Zealand English. From a broadly representative sample of 6327 two-year-olds ("Growing Up in New Zealand"), 6090 mothers (96%) reported their children understood English, and 763 mothers (12%) reported their children understood…

  4. Te Reo Maori as a Subject: The Impact of Language Ideology, Language Practice, and Language Management on Secondary School Students' Decision Making

    Science.gov (United States)

    Jeurissen, Maree

    2014-01-01

    Te reo Maori, the Indigenous language of Aotearoa (New Zealand), remains 'endangered' despite concentrated ongoing efforts to reverse declining numbers of speakers. Most of these efforts have focused on te reo Maori immersion education settings as these were considered the most effective means to ensure the survival of the language (May &…

  5. Te Reo Maori Ka Rere: "Talknology" and Maori Language as a Language of Choice

    Science.gov (United States)

    Lemon, Ruth

    2017-01-01

    This opinion piece aims to grow awareness of a range of technological initiatives that are supporting Maori language regeneration. These initiatives have been chosen because they have communities of users. This piece could be useful to educators who want to learn about the options that are available in this area, or students of Maori language for…

  6. "Mainstreaming" Te Reo Maori: Beyond Indifference and Tokenism in the Classroom

    Science.gov (United States)

    Ngapo, Koro

    2013-01-01

    This paper examines why Maori language needs to be taught accurately at the early stages of initial teacher education programmes and continue for the duration of a teacher education student's degree. If teacher education faculties are permitting their students to mispronounce Maori names or words, they are in fact doing a disservice, not only to…

  7. Te Rita Papesch: Case Study of an Exemplary Learner of Maori as an Additional Language

    Science.gov (United States)

    Ratima, Matiu Tai; Papesch, Te Rita

    2014-01-01

    This paper presents a case study of the life experiences of one exemplar adult second language Maori learner--Te Rita Papesch. Te Rita was one of 17 participants who were interviewed as a part of the first author's PhD study which sought to answer the question: what factors lead to the development of proficiency in te reo Maori amongst adult…

  8. Exploring Goals and Motivations of Maori Heritage Language Learners

    Science.gov (United States)

    Te Huia, Awanui

    2015-01-01

    Motivations of Maori heritage language learners are explored within this qualitative study. "Te reo" Maori (the Maori language) is currently classed as endangered (Reedy et al., 2011), which calls for the exploration of the motivational experiences of Maori heritage language learners. A total of 19 interviews with beginner, intermediate…

  9. Using Mobile Technology to Encourage Mathematical Communication in Maori-Medium Pangarau Classrooms

    Science.gov (United States)

    Allen, Piata

    2017-01-01

    Maori-medium pangarau classrooms occupy a unique space within the mathematics education landscape. The language of instruction is an endangered minority language and many teachers and learners in Maori-medium pangarau classrooms are second language (L2) learners of te reo Maori. Mobile technology could be used in Maori-medium pangarau classrooms…

  10. Living and Learning as Maori: Language Stories from Three Generations

    Science.gov (United States)

    Tocker, Kimai

    2017-01-01

    Through tracing in detail the story of schooling for three individuals, this article provides a rich description of the way that education impacted on the lives of many Maori between the early 1900s and the year 2000. Although there is extensive research on the historical colonising effects of schooling on Maori and te reo Maori (the Maori…

  11. Maori Mentors: Expectations and Perceptions

    Science.gov (United States)

    Barnett, Shirley; Te Wiata, Ina

    2017-01-01

    This article is informed by a kaupapa Maori methodology and reports on a "by Maori for Maori" peer mentoring programme. The programme, offered by the College of Business at Massey University, focuses on Maori students who are studying at a distance. We outline the programme and the experiences and perceptions from kanohi ki te kanohi…

  12. Maori English

    Science.gov (United States)

    Maclagan, Margaret; King, Jeanette; Gillon, Gail

    2008-01-01

    The Maori language is the language of the indigenous people of New Zealand. Today, not all Maori speak the Maori language, and many Maori as well as non-Maori speak Maori English, the fastest growing of the main varieties of New Zealand English. This paper provides a background to the linguistic situation of the Maori populace in New Zealand,…

  13. Nga Tuakiri o te Tangata: Being Maori in Early Childhood Education

    Science.gov (United States)

    Rameka, Lesley

    2017-01-01

    Before the arrival of Europeans in Aotearoa, New Zealand and their subsequent settlement in the 1800s, there was no concept of a Maori identity. Over time, however, as a result of rapid colonisation, Maori became a minority population in New Zealand. Consequently, the term Maori as normal or usual, began to lose its meaning (Webber, 2008), and…

  14. Te Kotahitanga: Addressing Educational Disparities Facing Maori Students in New Zealand

    Science.gov (United States)

    Bishop, Russell; Berryman, Mere; Cavanagh, Tom; Teddy, Lani

    2009-01-01

    The major challenges facing education in New Zealand today are the continuing social, economic and political disparities within our nation, primarily between the descendants of the European colonisers and the Indigenous Maori people. These disparities are also reflected in educational outcomes. In this paper, an Indigenous Maori Peoples' solution…

  15. Maori Potential: Barriers to Creating Culturally-Responsive Learning Environments in Aotearoa/new Zealand: Te Timatanga O Te Ara--Kei Whea Te Ara?

    Science.gov (United States)

    Henderson, Lesleigh

    2013-01-01

    New Zealand Education reforms aligned with raising Maori student success are yet to result in Maori students reaching their educational potential (Howard, 2010; ERO, 2008; 2010). Why do many New Zealand teachers struggle to create and deliver programmes which allow Maori learners to succeed as Maori? What barriers and enablers exist today in New…

  16. Ka Pu Te Ruha, Ka Hao Te Rangatahi: Changes in Maori Warfare between the Period Prior to First European Contact and the End of the New Zealand Wars

    Science.gov (United States)

    2009-06-12

    attached to a six-foot long shaft. This spear would be used in a manner similar to the Zulu assegai and was intended to keep the victim in close...Christianity. The aim of the founder was peaceful opposition of dispossessing Maori from the land and strengthening Maori identity. 43 The movement became

  17. Youth Development: Maori Styles

    Science.gov (United States)

    Ware, Felicity; Walsh-Tapiata, Wheturangi

    2010-01-01

    Despite the innovative approach of the Youth Development Strategy Aotearoa and the applicability of its Rangatahi Development Package, the diverse realities and experiences of Maori youth are still presenting unique challenges to national policy in Aotearoa New Zealand. A Maori youth research approach that utilised a combination of action research…

  18. Maori-Inspired Masks

    Science.gov (United States)

    Henn-Percarpio, Cynthia

    2013-01-01

    During a recent summer, the author participated in a Hands Across the Water Teacher Exchange Program to New Zealand. This experience gave her the opportunity to see how people in a different country live on a day-to-day basis. For her, one of the more interesting aspects of New Zealand was its indigenous culture, the Maori. In this activity, the…

  19. Reducing Maori and Pacific Inequalities

    OpenAIRE

    The Treasury

    2001-01-01

    Over the last fifty years the Maori and non-Maori populations have slowly and unevenly become more similar on a range of key demographic, social and economic outcomes. This has principally been driven by increased geographic and social proximity between the two groups. There is evidence that similar processes may be operating for migrant peoples from the Pacific. Many Maori and Pacific people do better than the population median. Conversely, on most outcomes, a much greater number of people o...

  20. Promoting the Maori Language to Non-Maori: Evaluating the New Zealand Government's Approach

    Science.gov (United States)

    de Bres, Julia

    2011-01-01

    New Zealand's two main government Maori language planning agencies, the Maori Language Commission and the Ministry of Maori Development, have engaged for some time in language planning targeting the attitudes and behaviours of non-Maori New Zealanders towards the Maori language. This activity is undertaken on the basis that the attitudes and…

  1. Te Ira Tangata: A Zelen randomised controlled trial of a treatment package including problem solving therapy compared to treatment as usual in Maori who present to hospital after self harm

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    Wikiriwhi Karen

    2011-05-01

    Full Text Available Abstract Background Maori, the indigenous people of New Zealand, who present to hospital after intentionally harming themselves, do so at a higher rate than non-Maori. There have been no previous treatment trials in Maori who self harm and previous reviews of interventions in other populations have been inconclusive as existing trials have been under powered and done on unrepresentative populations. These reviews have however indicated that problem solving therapy and sending regular postcards after the self harm attempt may be an effective treatment. There is also a small literature on sense of belonging in self harm and the importance of culture. This protocol describes a pragmatic trial of a package of measures which include problem solving therapy, postcards, patient support, cultural assessment, improved access to primary care and a risk management strategy in Maori who present to hospital after self harm using a novel design. Methods We propose to use a double consent Zelen design where participants are randomised prior to giving consent to enrol a representative cohort of patients. The main outcome will be the number of Maori scoring below nine on the Beck Hopelessness Scale. Secondary outcomes will be hospital repetition at one year; self reported self harm; anxiety; depression; quality of life; social function; and hospital use at three months and one year. Discussion A strength of the study is that it is a pragmatic trial which aims to recruit Maori using a Maori clinical team and protocol. It does not exclude people if English is not their first language. A potential limitation is the analysis of the results which is complex and may underestimate any effect if a large number of people refuse their consent in the group randomised to problem solving therapy as they will effectively cross over to the treatment as usual group. This study is the first randomised control trial to explicitly use cultural assessment and management. Trial

  2. Relating BIP and Reo

    NARCIS (Netherlands)

    K.P.C. Dokter (Kasper); S.-S.T.Q. Jongmans (Sung-Shik); F. Arbab (Farhad); S. Bliudze (Simon)

    2015-01-01

    textabstractCoordination languages simplify design and development of concurrent systems. Particularly, exogenous coordination languages, like BIP and Reo, enable system designers to express the interactions among components in a system explicitly. In this paper we establish a formal relation

  3. Relating BIP and Reo

    NARCIS (Netherlands)

    K.P.C. Dokter (Kasper); S.-S.T.Q. Jongmans (Sung-Shik); F. Arbab (Farhad); S. Bliudze (Simon); S. Knight; I. Lanese; A. Lluch Lafuente; H.T. Vieira

    2015-01-01

    htmlabstractCoordination languages simplify design and development of concurrent systems. Particularly, exogenous coordination languages, like BIP and Reo, enable system designers to express the interactions among components in a system explicitly. In this paper we establish a formal relation

  4. Maori-Pasifika relations: A problematic paradox?

    NARCIS (Netherlands)

    Meijl, A.H.M. van

    2014-01-01

    Maori people maintain ambiguous relations with the rest of the Pacific. Genealogical relationships continue to be celebrated in ongoing connections across a wide range of domains and discourses, but the colonial history of New Zealand has also turned Maori into a community of indigenous people that

  5. A Maori Pedagogy: Weaving the Strands Together

    Science.gov (United States)

    Stucki, Paora

    2012-01-01

    Literature on Maori pedagogy up until now has been disparate, some dealing with methodological issues, some with learning theory, some with environment and so forth. This article seeks to build one comprehensive picture of Maori pedagogy by weaving the myriad disparate themes in the literature into one unifying model. It is based on an EdD study…

  6. Supervising Research in Maori Cultural Contexts: A Decolonizing, Relational Response

    Science.gov (United States)

    Berryman, Mere; Glynn, Ted; Woller, Paul

    2017-01-01

    We have collaborated for 25 years as indigenous Maori and non-Maori researchers undertaking research with Maori families, their schools and communities. We have endeavored to meet our responsibilities to the Maori people (indigenous inhabitants of New Zealand) and communities with whom we have researched, as well as meet the requirements and…

  7. Exploring "Whakaaro": A Way of Responsive Thinking in Maori Research

    Science.gov (United States)

    Mika, Carl; Southey, Kim

    2018-01-01

    The experience of researching as a Maori student within academia will often raise questions about how and whether the student's research privileges Maori world views and articulates culturally specific epistemologies. This study offers some theorising, from the perspectives of a Maori doctoral student and her Maori supervisor (the authors of this…

  8. Lost in Translation: Western Representations of Maori Knowledge

    Science.gov (United States)

    Mika, Carl; Stewart, Georgina

    2017-01-01

    We recently attended a conference at which a non-Maori presenter, drawing on a particular metaphor already established by Maori writers, related Maori natural world features to a research method. The presentation was useful because it highlighted several issues that call for our concern as Maori philosophers. In this article, we outline these…

  9. Kaupapa Maori Methodology: Trusting the Methodology through Thick and Thin

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    Hiha, Anne Aroha

    2016-01-01

    Kaupapa Maori is thoroughly theorised in academia in Aotearoa and those wishing to use it as their research methodology can find support through the writing of a number of Maori academics. What is not so well articulated, is the experiential voice of those who have used Kaupapa Maori as research methodology. My identity as a Maori woman…

  10. Maori challenges and crown responsibilities: Maori policymaker ideas on smokefree policy options.

    Science.gov (United States)

    Gifford, Heather; Parata, Kiri; Thomson, George

    2010-11-26

    To determine obstacles/opportunities within policy processes, for smokefree interventions appropriate to Maori. In particular, to explore Maori policymakers' ideas on how to achieve progress on smokefree homes, cars and community property. Documents and interviews with 16 senior Maori officials and Members of Parliament, and nine interviews in two case studies, were used to explore Maori policymakers' ideas for (i) Progress, within relevant policy processes, on smoking in homes, cars and community property; (ii) Particular interventions that the interviewees felt were most and least effective, practical, sustainable, politically feasible or desirable in some way; (iii) The context, and obstacles and opportunities for such interventions. The case studies were of a Maori health service and a group of Maori District Health Board managers. Several key themes emerged from the research including, (i) children as drivers for change, (ii) strong national and local indigenous leadership needed for change, (iii) delivering smokefree messages as part of wider healthy living approaches, (iv) targeting of the messages for greatest impact for Maori, (v) need for a Maori approach, not a general approach, (vi) central and local government having a significant role in the prevention of tobacco harm, (vii) ideas on how tobacco tax revenue should be spent on tobacco control, and (viii) the rights of children to smokefree environments. Results indicate that indigenous specific approaches and indigenous leadership are critical for Maori tobacco-free advances. Harnessing indigenous values and principles related to health, family and children was the preferred method of these Maori policymakers for delivering social marketing messages.

  11. "Canaries in the Coal Mine": The Reframing of Biculturalism and Non-Maori Participation in Maori Language Learning

    Science.gov (United States)

    Lourie, Megan

    2011-01-01

    Maori language education policy documents reflect an underlying ambivalence about the desired outcomes for non-Maori learners participating in "as-a-subject" Maori language learning. The view of the Maori language as a national language may be in the process of being replaced by a view that identifies the language primarily as a cultural…

  12. Communicating Culture: An Exploratory Study of the Key Concepts in Maori Culture on Maori Web Sites

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    Zlatko J Kovacic

    2001-01-01

    Full Text Available We examine how accurately the belief system or cultural concepts of Maori, the indigenous people of New Zealand, is reconstructed in the virtual world of the Internet. Nine Maori web sites were searched using a list of 44 key concepts in Maori culture. We registered how many pages within a particular web site contain each of the key concepts. These numbers were set up in a data matrix for further statistical analysis. The Multidimensional Scaling method was used to construct a spatial representation of Maori web sites in the space generated by the key concepts in Maori culture. Using the correlation coefficients between derived dimensions and the key concepts we interpreted three dimensions as General Cultural, Intra-tribe Dynamics and Educational. The position of each Maori web site in this space has been located and described.

  13. Listening and Learning from Rangatahi Maori: The Voices of Maori Youth

    Science.gov (United States)

    Berryman, Mere; Eley, Elizabeth; Copeland, David

    2017-01-01

    This paper presents three stories-over-time of the secondary schooling experiences of New Zealand's rangatahi Maori--or Maori youth. The stories span fifteen years of New Zealand schooling and are told from three perspectives: the experiences of the students as told in their own words; the voices of youth within the prevailing political contexts…

  14. Theoretical Claims and Empirical Evidence in Maori Education Discourse

    Science.gov (United States)

    Rata, Elizabeth

    2012-01-01

    Post-Marxist critical sociology of education has influenced the development of indigenous ("kaupapa") Maori educational theory and research. Its effects are examined in four claims made for Maori education by indigenous theorists. The claims are: indigenous kaupapa Maori education is a revolutionary initiative; it is a cultural solution…

  15. "We Are Family": Maori Success in Foundation Programmes

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    McMurchy-Pilkington, Colleen

    2013-01-01

    This paper considers the question: What constitutes an optimal learning environment for Maori learners in foundation programmes? Using Kaupapa Maori methodology, nearly 100 adult Maori (Indigenous) students in Aotearoa/New Zealand were interviewed from a range of tertiary providers of foundation programmes. State-funded foundation programmes that…

  16. Te Kotahitanga: Culturally Responsive Professional Development for Teachers

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    Bishop, Russell; Berryman, Mere

    2010-01-01

    Te Kotahitanga is a research and professional development project that aims to support teachers to raise the achievement of New Zealand's indigenous Maori students in public/mainstream classrooms. An Effective Teaching Profile, developed from the voices of Maori students, their families, principals and some of their teachers, provides direction…

  17. Maori Men and the Grief of SIDS

    Science.gov (United States)

    Edwards, Shane; McCreanor, Tim; Ormsby, Manga; Tuwhangai, Nick; Tipene-Leach, David

    2009-01-01

    The loss of a baby is always hard to cope with and the grieving process is likely to be difficult. Interventions to work with Sudden Infant Death Syndrome (SIDS) families have improved grieving outcomes for many but the needs of Maori fathers are not well understood or catered to by existing services. This article presents narrative data from…

  18. A Compositional Semantics for Stochastic Reo Connectors

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    Young-Joo Moon

    2010-07-01

    Full Text Available In this paper we present a compositional semantics for the channel-based coordination language Reo which enables the analysis of quality of service (QoS properties of service compositions. For this purpose, we annotate Reo channels with stochastic delay rates and explicitly model data-arrival rates at the boundary of a connector, to capture its interaction with the services that comprise its environment. We propose Stochastic Reo automata as an extension of Reo automata, in order to compositionally derive a QoS-aware semantics for Reo. We further present a translation of Stochastic Reo automata to Continuous-Time Markov Chains (CTMCs. This translation enables us to use third-party CTMC verification tools to do an end-to-end performance analysis of service compositions.

  19. Awhina Revolution: A Bayesian Analysis of Undergraduate and Postgraduate Completion Rates from a Program for Maori and Pacific Success in STEM Disciplines

    Science.gov (United States)

    Richardson, Ken; Clark, Zaramasina; Gaines, Michael; Kingi, Hautahi; Miller, Sonja; Pearson, Willie, Jr.; Richardson, Liz

    2018-01-01

    Maori and Pacific students generally do not attain the same levels of tertiary success as New Zealanders of European descent, particularly in science, technology, engineering, and mathematics (STEM) subjects. Te Ropu Awhina (Awhina), an equity initiative at Victoria University of Wellington in New Zealand between 1999 and 2015, aimed to produce…

  20. Coordination models Orc and Reo compared

    NARCIS (Netherlands)

    J.M.P. Proença (Jose); D.G. Clarke (David)

    2008-01-01

    htmlabstractOrc and Reo are two complementary approaches to the problem of coordinating components or services. On one hand, Orc is highly asynchronous, dynamic, and based on ephemeral connections to services. On the other hand, Reo is based on the interplay between synchronization and mutual

  1. A Compositional Semantics for Stochastic Reo Connectors

    NARCIS (Netherlands)

    Y.-J. Moon (Young-Joo); A.M. Silva (Alexandra); , C. (born Köhler, , C.) Krause (Christian); F. Arbab (Farhad)

    2010-01-01

    htmlabstractIn this paper we present a compositional semantics for the channel-based coordination language Reo which enables the analysis of quality of service (QoS) properties of service compositions. For this purpose, we annotate Reo channels with stochastic delay rates and explicitly model

  2. Brown Bodies, White Coats: Postcolonialism, Maori Women and Science

    Science.gov (United States)

    McKinley, Elizabeth

    2005-01-01

    In Aotearoa New Zealand journeys of discovery and colonization were also scientific journeys that brought "Maori woman" under the intellectual control of the emerging "scientific" academy. This paper argues that the historical construction of "Maori woman" through the discourses of Enlightenment science continues to…

  3. Maori in the Kingdom of the Gaze: Subjects or Critics?

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    Mika, Carl; Stewart, Georgina

    2016-01-01

    For Maori, a real opportunity exists to flesh out some terms and concepts that Western thinkers have adopted and that precede disciplines but necessarily inform them. In this article, we are intent on describing one of these precursory phenomena--Foucault's Gaze--within a framework that accords with a Maori philosophical framework. Our discussion…

  4. Being Maori: Culturally Relevant Assessment in Early Childhood Education

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    Rameka, Lesley Kay

    2011-01-01

    Concern has been raised about the under-achievement of Maori children in education. The problem has tended to be located with Maori children rather than with assessments. Clearly if one takes a sociocultural perspective achievement is situated. Although studies in early childhood education have examined and developed assessment tools and…

  5. Maori University Graduates: Indigenous Participation in Higher Education

    Science.gov (United States)

    Theodore, Reremoana; Tustin, Karen; Kiro, Cynthia; Gollop, Megan; Taumoepeau, Mele; Taylor, Nicola; Chee, Kaa-Sandra; Hunter, Jackie; Poulton, Richie

    2016-01-01

    Maori, the indigenous population of New Zealand, are gaining university qualifications in greater numbers. This article describes the history of Maori university graduates, their current situation and the implications for indigenous futures. Section one provides a brief overview of historical policies and practices that, similar to those used on…

  6. Maori Identification, Alcohol Behaviour and Mental Health: A Review

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    Ebbett, Erin; Clarke, Dave

    2010-01-01

    The impact of Maori identification on alcohol behaviour and mental health and has been neglected in the psychological literature. This paper consists of a review of literature on the history of alcohol use in New Zealand and its impact on indigenous Maori, on their cultural identity and on their mental health. Previous research has been primarily…

  7. Perfecting the Partnership: Revitalising the Maori Language in New Zealand Education and Society 1987-2014

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    Benton, Richard A.

    2015-01-01

    This paper looks at aspects of Maori language revitalisation since the passage of the Maori Language Act, 1987 which gave official status to the language. It is a sequel to an article on Maori language in education published in this journal the following year [Benton, R. A. (1988). "The Maori language in New Zealand education."…

  8. Putting "Maori" in the Mainstream: Student Teachers' Reflections of a Culturally Relevant Pedagogy

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    Sexton, Steven S.

    2011-01-01

    This paper reports on student teachers' experiences of an education program that was explicitly designed to be grounded in both Kaupapa Maori and mainstream pedagogy. This program started from the Kaupapa Maori view to be Maori as Maori. This was then supported by mainstream epistemology of New Zealand focused good teaching practice. A Kaupapa…

  9. Transitioning from Maori-Medium to English-Medium Education: Emerging Findings of a Pilot Study

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    Hill, Richard

    2016-01-01

    Maori-bilingual education in New Zealand has come a long way towards injecting life into the Maori language. However, only a small number of families commit to bilingual education for the long term. This paper discusses why Maori parents either turn away from Maori-bilingual education or prematurely transition to English-medium schools. It then…

  10. Maori experiences and perceptions of gout and its treatment: a kaupapa Maori qualitative study

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    Te Karu L

    2013-09-01

    Full Text Available INTRODUCTION: The prevalence of gout among Maori is one of the highest in the world. This study explores the perceptions, understanding and treatment of gout among Maori. METHODS: A qualitative general inductive approach was used, guided by kaupapa Maori principles. Participants included 12 Maori aged 48-79 years with gout. Semi-structured interviews were undertaken, taped and transcribed. Themes were identified from transcripts. FINDINGS: Participants described overwhelming sufferance due to gout, which was sometimes considered inevitable. All participants believed or had been informed that gout is caused by food and/or drink. This led to feelings of self-blame and blame from partners and employers. Whanau (family were a resource for information and a support when independence was limited. Rongoa (traditional medicine played a role in the lives of rural but not urban participants. Many reported stoicism, putting up with pain and putting others before themselves, as the 'Maori way'. Medicines used for gout management were predominantly non-steroidal anti-inflammatory drugs, colchicine and prednisone, with allopurinol only playing a role late in the disease. Medications were often poorly understood and consequently improperly used. Relationships with health professionals were important, but cultural, financial and time barriers impaired access and understanding. Gout had a huge, negative impact on the lives of participants. CONCLUSION: The quality of lives of many people with gout could be improved by better understanding through educational campaigns for health professionals and the community. Culturally sensitive health care systems and a paradigm shift in gout management and early preventive treatment are needed.

  11. Cultural/Community Mentoring with Maori and Pacific Electrical Apprentices

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    Chris Holland

    2012-12-01

    Full Text Available New Zealand government policy documents over the last decade have committed to supporting Maori and Pasifika learners, yet still today there is little real support in place for learners in apprenticeships. There is even less support in place that acknowledges the cultural dimension of learning in the workplace. This paper discusses the establishment and review of a development project which sets out to provide culturally supportive mentoring for Maori and Pasifika apprentices. The project sought to do this by engaging experienced Maori and Pasifika tradesmen who were located in the local communities of their learners.

  12. Combine and conquer: Relating BIP and Reo

    NARCIS (Netherlands)

    K.P.C. Dokter (Kasper); S.-S.T.Q. Jongmans (Sung-Shik); F. Arbab (Farhad); S. Bliudze (Simon)

    2017-01-01

    textabstractCoordination languages simplify design and development of concurrent systems. Particularly, exogenous coordination languages, like BIP and Reo, enable system designers to express the interactions among components in a system explicitly. A formal relation between exogenous coordination

  13. Barriers to Maori sole mothers’ primary health care access

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    Lee R

    2013-12-01

    Full Text Available INTRODUCTION: International research consistently shows that sole mothers experience poorer health and suboptimal health care access. New Zealand studies on sole mothers' health report similar findings. The aim of this exploratory research was to better understand the experiences of Maori sole mothers' access to health services, particularly primary health care, for personal health needs. METHODS: This qualitative study employed a general inductive design informed by a Kaupapa Maori approach, providing guidance on appropriate cultural protocols for recruiting and engaging Maori participants. Distributing written information and snowballing techniques were used to purposively recruit seven Maori sole mothers. Data collection involved semi-structured interviews which were digitally recorded and transcribed verbatim. Data were analysed using general inductive thematic analysis to identify commonalities and patterns in participants' experiences. FINDINGS: The dominant themes that emerged captured and described participants' experiences in accessing health care. The major barrier to access reported was cost. Compounding cost, transport difficulties and location or scheduling of services were additional barriers to health service accessibility. Child-related issues also posed a barrier, including prioritising children's needs and childcare over personal health needs. CONCLUSION: The findings illuminate Maori sole mothers' experiences of accessing health care and the complex socioeconomic inequalities affecting access options and uptake of services. Further investigation of barriers to access is needed. The study has implications for addressing barriers to access at policy, funding and practice levels to improve health outcomes and equitable health care access for Maori sole mothers.

  14. Characteristics of sarcoidosis in Maori and Pacific Islanders.

    Science.gov (United States)

    Wilsher, Margaret L; Young, Lisa M; Hopkins, Raewyn; Cornere, Megan

    2017-02-01

    Ethnicity is strongly associated with variable clinical presentation in sarcoidosis but the association between ethnicity and clinical characteristics has not previously been described in patients of Polynesian ancestry, Maori and Pacific Islander (PI). The objective of this study was to describe the clinical characteristics of sarcoidosis in Maori and PI patients and determine if those were different to European patients. A retrospective review of the medical records of 406 patients (69 Maori/PI) attending a specialist interstitial lung disease (ILD) clinic. The population (207 females, mean age at presentation: 36) reflected the current New Zealand census data (2013) with only people of Indian ethnicity over-represented. Parenchymal lung involvement was uncommon in Maori and PI patients (21% Scadding stage 2, 2% stage 3), and no patient had extensive pulmonary fibrosis (stage 4). Computed tomography (CT) patterns of sarcoid parenchymal lung involvement were less commonly reported for Maori/PI. There were no differences in respect of baseline lung function or requirement for treatment. Ocular and skin involvement occurred more frequently in Maori and PI (P = 0.0045, P = 0.03), and erythema nodosum was more common in Caucasians (P = 0.0008). People of Polynesian ancestry appear to have less pulmonary and more extra-pulmonary manifestations of sarcoidosis. This adds to our knowledge that sarcoidosis heterogeneity is influenced by ethnicity. © 2016 Asian Pacific Society of Respirology.

  15. Regional differences in incidence of gastric and colonic cancer in the Maori of New Zealand

    Science.gov (United States)

    Thompson, A

    2002-01-01

    Background: It is known that there are ethnic differences in cancer in New Zealand between Maori (the indigenous people) and non-Maori, however, until now no regional comparisons have been made. Study design: A retrospective study of patients diagnosed at Whangarei Hospital, New Zealand between 1995 and 1997 with gastric or colonic cancer was combined with population data from the 1996 census for Whangarei District to calculate incidence figures. The incidence of cancer was compared to national rates. Results: Between 1995 and 1997, 19 Maori and 24 non-Maori were diagnosed with gastric cancer, and 10 Maori and 125 non-Maori with colonic cancer. The age standardised rates (per 100 000) for Maori and non-Maori with gastric caner were 68.3 and 7.9 respectively. Gastric cancer is known to be increased in the Maori, but in Whangarei was significantly higher than the national Maori rates (20.5). There was no difference in the rate of colonic cancer in the Maori and non-Maori in Whangarei, again this differs from the national trends, in which the Maori are protected against cancer. Conclusion: This study highlights that there is still much more to be learnt in understanding the aetiology of gastrointestinal cancers, to explain such strong regional differences. PMID:12151659

  16. An Old Problem with New Directions: Maori Language Revitalisation and the Policy Ideas of Youth

    Science.gov (United States)

    Albury, Nathan John

    2016-01-01

    Legislative changes are afoot in New Zealand that are formalising an ideological shift in policy that decreasingly positions the Maori language a matter of interethnic national identity but increasingly as one for Maori self-determination. The Waitangi Tribunal (WAI262, Waitangi Tribunal, 2011) established that, from here on, Maori language policy…

  17. Looking Back to Look Forward: Maori Cultural Values and the Impact on Career

    Science.gov (United States)

    Reid, Lynette

    2011-01-01

    The career stories of 22 Maori in this study expressed the dynamic cultural contexts in which career processes have been enacted. A new typology of cultural career identities was developed focusing on diversity among Maori on issues pertaining to what being Maori means to them and the subsequent influence on participants' career stories. The three…

  18. Developing a Maori Language Mathematics Lexicon: Challenges for Corpus Planning in Indigenous Language Contexts

    Science.gov (United States)

    Trinick, Tony; May, Stephen

    2013-01-01

    Over the last 25 years, there has been significant modernisation and elaboration of the Maori language mathematics lexicon and register to support the teaching of (Western) mathematics as a component of Maori-medium schooling. These developments are situated within the wider Maori language revitalisation movement in Aotearoa/New Zealand, of which…

  19. Maori Cultural Efficacy and Subjective Wellbeing: A Psychological Model and Research Agenda

    Science.gov (United States)

    Houkamau, Carla A.; Sibley, Chris G.

    2011-01-01

    Maori, the indigenous peoples of New Zealand, experience a range of negative outcomes. Psychological models and interventions aiming to improve outcomes for Maori tend to be founded on a "culture-as-cure" model. This view promotes cultural efficacy as a critical resilience factor that should improve outcomes for Maori. This is a founding…

  20. Ladrillos silicocalcáreos: Sus propiedades

    OpenAIRE

    Editorial, Equipo

    2017-01-01

    El desarrollo tan considerable que ha alcanzado en los últimos años la fabricación de ladrillos silicocalcáreos se debe, en gran parte, a las características que presentan dichos ladrillos que los hacen muy adecuados para ciertos casos y necesarios en otros.

  1. Genetics of club foot in Maori and Pacific people

    Science.gov (United States)

    Chapman, C.; Stott, N; Port, R. V.; Nicol, R.

    2000-01-01

    The role of major gene and multifactorial inheritance in the aetiology of club foot in the New Zealand Polynesian population was studied using 287 New Zealand Maori and Pacific club foot families. The club foot family data were analysed by complex segregation analysis under the mixed model using the computer program POINTER. This analysis shows that the best genetic model for club foot in this population is a single dominant gene with a penetrance of 33% and a predicted gene frequency of 0.9%. These data provide a scientific foundation for molecular studies in the Maori and Polynesian population to identify putative club foot genes.


Keywords: club foot; New Zealand Maori; complex segregation analysis PMID:10978359

  2. Whiti Ki Runga! Gifted and Talented Maori Learners

    Science.gov (United States)

    Macfarlane, Angus; Moltzen, Roger

    2005-01-01

    The importance of identifying and nurturing the gifts and talents of young people is now more widely accepted in New Zealand than it has been in the past. In this country the approach to meeting this challenge must reflect an understanding and acknowledgement of Maori conceptions of giftedness and talent. It is proposed here that the…

  3. Early Intervention Services: Effectively Supporting Maori Children and their Families

    Science.gov (United States)

    Berryman, Mere; Woller, Paul

    2011-01-01

    This paper examines Early Intervention (EI) service provision from within one Ministry of Education region in New Zealand. It does this in order to better understand what works well and what needs to change if children from Maori families, of Early Childhood age, are to be provided with the most effective EI services. By engaging with Maori…

  4. Improving Access to Health Care Among New Zealand’s Maori Population

    Science.gov (United States)

    Ellison-Loschmann, Lis; Pearce, Neil

    2006-01-01

    The health status of indigenous peoples worldwide varies according to their unique historical, political, and social circumstances. Disparities in health between Maoris and non-Maoris have been evident for all of the colonial history of New Zealand. Explanations for these differences involve a complex mix of components associated with socioeconomic and lifestyle factors, availability of health care, and discrimination. Improving access to care is critical to addressing health disparities, and increasing evidence suggests that Maoris and non-Maoris differ in terms of access to primary and secondary health care services. We use 2 approaches to health service development to demonstrate how Maori-led initiatives are seeking to improve access to and quality of health care for Maoris. PMID:16507721

  5. Living (stained calcareous benthic foraminifera from recent sediments off Concepción, central-southern Chile (~36° S Foraminíferos bentónicos calcáreos vivos (teñidos en sedimentos recientes de Concepción, Chile centro-sur (~36° S

    Directory of Open Access Journals (Sweden)

    RAÚL TAPIA

    2008-09-01

    Full Text Available This study examines onshore-offshore and vertical distribution of living (Rose Bengal stained benthic foraminifera (> 180 μm fraction from three sediment stations along a bathymetric transect off Concepción, Chile (station 18 = 88 m water depth, station 26 = 120 m, station 40 = 1,030 m, within and below the oxygen minimum zone. All cores were collected in austral winter. Calcareous foraminifera dominated the three stations. The species composition, living foraminifera density, and vertical distribution patterns within the sediment changed in accordance with bottom water dissolved oxygen concentration and food availability. Onshore-offshore pattern revealed overall highest living foraminiferal densities at shelf stations 18 and 26 where bottom water dissolved oxygen was lowest (~ 0.2 mL-1 and content in labile organic matter highest. Within the sediment, maximum relative abundances (50-60 % of living organisms were found in the 0-1 cm interval at the organic-rich and oxygen-poor shelf stations 18 and 26. In the well-oxygenated (2.7 mL-1 slope station 40, 70 % of living foraminifera were observed deeper than the first centimeter. The number of species and the contribution of the > 250 μm fraction to the total fauna larger than 180 μm increased offshore. Nonionella auris (d'Orbigny dominated at stations 18 and 26 while a more diverse foraminifera fauna was found at station 40. This study provides the first quantitative data on living benthic foraminifera in the area; seasonal and interannual changes are not addressed.Este estudio examina la distribución costa-océano y vertical de los foraminíferos bentónicos calcáreos (fracción > 180 im vivos (teñidos en tres estaciones a lo largo de un transecto batimétrico frente al área de Concepción, Chile (estación 18 = 88 m, estación 26 = 120 m, estación 40 = 1.030 m de profundidad, dentro y bajo la zona mínima de oxígeno. Todos los testigos de sedimento fueron recolectados durante el per

  6. The Re/Os Clock Revisited

    CERN Multimedia

    Leal, L C; Kitis, G; Guber, K H; Quaranta, A; Koehler, P E

    2002-01-01

    The purpose of the proposed project of an accurate measurement of the relevant neutron cross sections of $^{186}$Os and $^{187}$Os is to remove the principal nuclear physics uncertainties in the analysis of the Re/Os cosmochronometer. The necessary cross section information will be obtained in complementary experiments at the nTOF facility at CERN and at the Karlsruhe Van de Graaff accelerator. Transformation of these results into significantly improved stellar reaction rates will allow to evaluate the age of the elements in the framework of galactic chemical evolution models.

  7. Calciphylaxis - A case study in a patient with Maori heritage.

    Science.gov (United States)

    Kingi, Lawrence; Grech, Roger; Lam, Michael; Dissanayake, Ajith; Otter, Simon

    2016-11-01

    This case history describes a rare complaint - Calciphylaxis, seen in a New Zealand Maori patient undergoing renal dialysis. This condition causes non-healing tissue ulceration, typically with sepsis and is associated with a very high mortality rate. The need for vigilance among health professionals is highlighted, including the risk factors that may faciliate an early diagnosis; together with the value associated with a multi-disciplinary team approach to management. Copyright © 2016 Tissue Viability Society. All rights reserved.

  8. The Juxtaposition of Maori Words with English Concepts. 'Hauora, Well-Being' as Philosophy

    Science.gov (United States)

    Heaton, Sharyn

    2018-01-01

    Within the New Zealand curriculum, hauora has been co-opted as an underlying and interdependent concept at the heart of the learning area of health and physical education. Hauora is identified as a Maori philosophy of well-being, advocating a Maori world view of hauora. Contemporary understandings of hauora as a Maori philosophy of health are…

  9. Educational Achievement in Maori: The Roles of Cultural Identity and Social Disadvantage

    Science.gov (United States)

    Marie, Dannette; Fergusson, David M.; Boden, Joseph M.

    2008-01-01

    The present study investigates the roles of Maori cultural identity and socio-economic status in educational outcomes in a New Zealand birth cohort studied from birth to the age of 25. There were statistically significant (all p values less than 0.01) associations between cultural identity and educational outcomes, with those of Maori ethnic…

  10. Patterns of Social Expectations among Maori and European Children in New Zealand.

    Science.gov (United States)

    Rotheram-Borus, Mary Jane; Petrie, Keith J.

    1996-01-01

    Assessed social expectations of 163 Maori and European New Zealanders aged 9 and 12 in response to videotaped social encounters. Ethnic differences were greater among younger children. Among Maori children, an enculturated pattern was associated with less assertiveness and lower self-concept, but was not with cross-ethnic acceptance. (SLD)

  11. Huakina Mai: A Kaupapa Maori Approach to Relationship and Behaviour Support

    Science.gov (United States)

    Savage, Catherine; Macfarlane, Sonja; Macfarlane, Angus; Fickel, Letitia; Hemi, Hemi Te

    2014-01-01

    This article presents the developmental stages of a nationwide whole-school strengths-based behavioural intervention by Maori and centring on Maori interests; an initiative that has the potential to transform educational success and opportunities. The initial phase involved a cycle of data collection. This was conducted via a series of focus…

  12. What Can Pakeha Learn from Engaging in Kaupapa Maori Educational Research? Working Paper 1

    Science.gov (United States)

    Barnes, Alex

    2013-01-01

    This working paper focuses on how Pakeha have become involved in Maori-determined and controlled educational research, and what issues inhibit and facilitate their work. This paper focuses on the experiences of four Pakeha educational researchers who have been engaged in different forms of kaupapa Maori research since the early 1990s. Placing…

  13. Steady-State Clozapine and Norclozapine Pharmacokinetics in Maori and European Patients

    Directory of Open Access Journals (Sweden)

    David B. Menkes

    2018-01-01

    Discussion: Clozapine bioavailability does not vary between Maori and European patients, and thus does not need to be considered in prescribing decisions. Additional studies are needed to identify if there are differences between Maori and European populations for drugs metabolized by other enzyme pathways.

  14. Equity in New Zealand University Graduate Outcomes: Maori and Pacific Graduates

    Science.gov (United States)

    Theodore, Reremoana; Taumoepeau, Mele; Kokaua, Jesse; Tustin, Karen; Gollop, Megan; Taylor, Nicola; Hunter, Jackie; Kiro, Cynthia; Poulton, Richie

    2018-01-01

    Higher education confers significant private and social benefits. Maori and Pacific peoples are under-represented within New Zealand universities and have poorer labour market outcomes (e.g., lower wages, under-represented in skilled professions). A New Zealand tertiary education priority is to boost Maori and Pacific success in an effort to…

  15. Exploring the Role of Identity in Maori Heritage Language Learner Motivations

    Science.gov (United States)

    Te Huia, Awanui

    2017-01-01

    Substantially less is known about the motivations of indigenous heritage language learners than the motivations of learners of colonial languages. This study explores the motivations of Maori indigenous New Zealanders and the identity-related motivations they have for learning their heritage language. Interviews with 19 Maori language learners…

  16. Nga Manu Korero: Revitalizing Communication, Customs and Cultural Competencies amongst Maori Students, Teachers, Whanau and Communities

    Science.gov (United States)

    Tinirau, Rawiri; Gillies, Annemarie

    2013-01-01

    The Nga Manu Speech Contest has grown to be one of the biggest and most positive events for New Zealand secondary school students where competitors articulate their thoughts and aspirations in both Maori and English. The contest is acknowledged as an avenue that enhances language and cultural development amongst Maori youth, yet no formal…

  17. Maori on the Silver Screen: the evolution of indigenous feature filmmaking in Aotearoa/New Zealand

    NARCIS (Netherlands)

    Martens, E.

    2012-01-01

    This article examines the evolution of Maori filmmaking since the 1980s and explores this Indigenous cinema in the context of developments in the New Zealand film industry. With Barry Barclay’s idea of ‘Fourth Cinema’ in mind, it focuses on the predominantly state-funded production of Maori feature

  18. Reducing smoking in pregnancy among Maori women: "aunties" perceptions and willingness to help

    NARCIS (Netherlands)

    Esdonk, T.; Glover, M.; Kira, A.; Wagemakers, A.

    2014-01-01

    Maori (the indigenous people of New Zealand) women have high rates of smoking during pregnancy and 42 % register with a lead maternity carer (LMC) after their first trimester, delaying receipt of cessation support. We used a participatory approach with Maori community health workers (‘‘Aunties’’) to

  19. Being, Flow and Knowledge in Maori Arts Education: Assessing Indigenous Creativity

    Science.gov (United States)

    Hindle, Rawiri; Hynds, Anne S.; Phillips, Hazel; Rameka, Lesley

    2015-01-01

    This article reflects on issues of Indigenous creativity in Maori arts education, along with what we see as problematic tensions of the assessment of intangible elements. Our writing is motivated by a desire to start a global dialogue on Indigenous/Maori epistemologies, pedagogies and ontologies, and the contradictions and tensions that threaten…

  20. Multiple identifications and the dialogical self: Maori youngsters and the cultural renaissance

    NARCIS (Netherlands)

    Meijl, A.H.M. van

    2006-01-01

    The renaissance of Maori culture and tradition has played a significant role in the political campaigns of New Zealand's indigenous population over the past few decades. At the same time, however, it has brought to light that many Maori youngsters are unable to construct a cultural identity in terms

  1. Science in the Maori-Medium Curriculum: Assessment of Policy Outcomes in Putaiao Education

    Science.gov (United States)

    Stewart, Georgina

    2011-01-01

    This second research paper on science education in Maori-medium school contexts complements an earlier article published in this journal (Stewart, 2005). Science and science education are related domains in society and in state schooling in which there have always been particularly large discrepancies in participation and achievement by Maori. In…

  2. "Ahakoa He Iti": Early Childhood Pedagogies Affirming of Maori Children's Rights to Their Culture

    Science.gov (United States)

    Rau, Cheryl; Ritchie, Jenny

    2011-01-01

    Research Findings: This paper considers the position of tamariki Maori, the indigenous children of Aotearoa (a Maori name for New Zealand), in relation to the impact of colonization on their rights, including a focus on the United Nations Declaration on the Rights of Indigenous Peoples and the current educational policy arena. It then provides an…

  3. Decolonisation through Critical Career Research and Action: Maori Women and Accountancy

    Science.gov (United States)

    McNicholas, Patty; Humphries, Maria

    2005-01-01

    The call for a just social order in Aotearoa (New Zealand) includes the transformation of mono-cultural institutions such as the accountancy profession. Maori women accountants in this research expressed concern about maintaining their identity as Maori while participating in the corporate culture of the firms in which they are employed. These…

  4. Synthesis of metallic ReO3 nanowires

    International Nuclear Information System (INIS)

    Myung, Dongshin; Lee, Yumin; Lee, Jaeyeon; Kim, Myung Hwa; Yu, Hak Ki; Lee, Jong-Lam; Baik, Jeong Min; Kim, Woong

    2010-01-01

    We present the synthesis of highly crystalline metallic rhenium trioxide (ReO 3 ) nanowires via a simple physical vapor transport at 300 C for the first time. Based on HRTEM, the ReO 3 nanowires exhibit a core of perfect cubic perovskite-type single crystal structure with a shell of thin amorphous and disordered structures of less than 2 nm in the near surface layers. Possibly this is due to proton intercalation induced by the surface reaction of single crystal ReO 3 with water. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. FHA Single Family REO Properties for Sale (NGDA)

    Data.gov (United States)

    Department of Housing and Urban Development — The U.S. Department of Housing and Urban Development's Real Estate Owned (REO) properties are a result of the Federal Housing Administration (FHA) paying a claim to...

  6. Early Maori settlement impacts in northern coastal Taranaki, New Zealand

    International Nuclear Information System (INIS)

    Wilmshurst, J.M.; Higham, T.F.G.; Allen, H.; Johns, D.; Phillips, C.

    2004-01-01

    Pollen and charcoal analyses of sediments from northern coastal Taranaki, New Zealand, show that Maori settlement impacts on the vegetation began with the burning of tall coastal forest in the mid-17th century. Forest was replaced with a fern-shrubland, and small wetlands expanded with changing hydrological conditions. This forest clearance was much later than in most regions of the country, where major forest disturbance and clearance began between AD 1200 and AD 1400. However, Maori were known to be using the forested coastal Taranaki landscape from at least AD 1300 to hunt the now extinct moa, and to collect shellfish, but neither of these activities necessarily required forest clearance or permanent settlement. Preserved rat-gnawed seeds in the wetland deposits provide evidence for the presence of the introduced kiore (Polynesian rat, Rattus exulans) in coastal Taranaki from about AD 1200, significantly before forest clearance or permanent human settlement. Although kiore were present in the coastal forests for as much as 400 years before forest clearance, the pollen records do not show any changes in forest composition during this time. (author). 58 refs., 4 figs., 5 tabs

  7. Energy expenditure and metabolism in Maori, Pacific Island and New Zealand European men

    International Nuclear Information System (INIS)

    Rush, E.; Laulu, M.S.; Mitchelson, E.; Plank, L.

    1999-01-01

    Obesity is an important risk factor for many diseases that contribute to premature death and illness. Particularly for Maori and Pacific Island people in New Zealand, death rates from diabetes, stroke and coronary heart disease are much higher than those of other New Zealanders. We hypothesise that the greater prevalence of obesity in Pacific Island and Maori groups compared to NZ European is related to metabolic differences. We have already shown significant differences in body composition and metabolism in young NZ European and Polynesian women. The goal of the proposed study is to determine whether such differences are also present among young NZ European, Pacific Island and Maori males. (author)

  8. Dissecting the Re-Os molybdenite geochronometer.

    Science.gov (United States)

    Barra, Fernando; Deditius, Artur; Reich, Martin; Kilburn, Matt R; Guagliardo, Paul; Roberts, Malcolm P

    2017-11-22

    Rhenium and osmium isotopes have been used for decades to date the formation of molybdenite (MoS 2 ), a common mineral in ore deposits and the world's main source of molybdenum and rhenium. Understanding the distribution of parent 187 Re and radiogenic daughter 187 Os isotopes in molybdenite is critical in interpreting isotopic measurements because it can compromise the accurate determination and interpretation of mineralization ages. In order to resolve the controls on the distribution of these elements, chemical and isotope mapping of MoS 2 grains from representative porphyry copper-molybdenum deposits were performed using electron microprobe and nano-scale secondary ion mass spectrometry. Our results show a heterogeneous distribution of 185,187 Re and 192 Os isotopes in MoS 2 , and that both 187 Re and 187 Os isotopes are not decoupled as previously thought. We conclude that Re and Os are structurally bound or present as nanoparticles in or next to molybdenite grains, recording a complex formation history and hindering the use of microbeam techniques for Re-Os molybdenite dating. Our study opens new avenues to explore the effects of isotope nuggeting in geochronometers.

  9. Meteor Beliefs Project: Meteors in the Maori astronomical traditions of New Zealand

    Science.gov (United States)

    Britton, Tui R.; Hamacher, Duane W.

    2014-02-01

    We review the literature for perceptions of meteors in the Maori culture of Aotearoa or New Zealand. We examine representations of meteors in religion, story, and ceremony. We find that meteors are sometimes personified as gods or children, or are seen as omens of death and destruction. The stories we found highlight the broad perception of meteors found throughout the Maori culture, and note that some early scholars conflated the terms comet and meteor.

  10. Cross-sectional study on prevalence, causes and avoidable causes of visual impairment in Maori children.

    Science.gov (United States)

    Chong, Cheefoong; Dai, Shuan

    2013-08-02

    To provide information and comparison pertaining to visual impairment of Maori children with other children in New Zealand in particular: prevalence of blindness, causes of visual impairment, and avoidable causes of visual impairment. Retrospective data collection utilising the WHO/PBL eye examination record for children with blindness and low vision at Blind and Low Vision Education Network New Zealand (BLENNZ), Homai. Individuals not of Maori ethnicity or over the age of 16 were excluded from the study. 106 blind and 64 low-vision Maori children were studied. The main cause of blindness in Maori children is cortical visual impairment. Twenty-eight percent of causes of blindness in this population are potentially avoidable with non-accidental injury as the main cause. The prevalence of blindness and low vision in children amounts to 0.05% and 0.03%, respectively. The prevalence and causes of childhood blindness are comparable to the other ethnic groups in New Zealand. The main difference lies in avoidable causes of blindness, which appeared to be much higher in the Maori population. The leading cause of avoidable blindness in Maori children is caused by non-accidental injuries.

  11. Archaeomagnetic studies of Maori Hangi Stones from New Zealand

    Science.gov (United States)

    Kinger, R.; Turner, G. M.; McFadgen, B.

    2014-12-01

    Global palaeosecular variation models still suffer from a paucity of high quality data from the SW Pacific region. Over the past two years we have worked to fill this gap with archaeomagnetic data - directions and palaeointensities - by studying the thermoremanent magnetization of Maori hangi cooking stones. Used as heat retainers, these stones are heated, frequently above the Curie temperatures of constituent magnetic minerals, before being buried in earth ovens. After removal of the food, hangi sites are often abandoned with the stones still in situ, carrying a record of the magnetic field in which they were last cooled. We have sampled a range of archaeological hangi sites throughout New Zealand, dating to early prehistoric times (ca 700 BP). The stones vary in lithology from andesites, originating from the central North Island volcanoes, favoured by Maori for their durability and with NRM intensities up to 30 A/m, to greywackes and schists from the main axial ranges, with NRMs as weak as 10-4A/m. In all cases, we have independently oriented and retrieved several stones, and we have made several specimens from each stone, either by drilling (standard cylindrical specimens) or sawing (pseudo-cubes) in the laboratory. We have calculated site mean palaeomagnetic directions from principal component analysis of thermal demagnetization data, discarding the data of stones that show evidence of disturbance. We have carried out palaeointensity experiments using a Coe/Thellier method with pTRM and tail checks, and with selection criteria modified to the situation. Rock magnetic experiments contribute to our understanding of the mineralogy, domain state and blocking temperature spectra. The palaeodirections fall between declinations of 348o and 24.5o, and inclinations of -46.4o and -72.4o, with palaeointensities between 43.7±1.4 and 81.3±6.1 mT. Most fall within the expected range of secular variation for New Zealand. However the palaeointensity of 81.34±6.08mT, from an

  12. Steady-State Clozapine and Norclozapine Pharmacokinetics in Maori and European Patients.

    Science.gov (United States)

    Menkes, David B; Glue, Paul; Gale, Christopher; Lam, Frederic; Hung, Cheung-Tak; Hung, Noelyn

    2018-01-01

    Clozapine is the most effective drug for treatment-resistant schizophrenia, but its use is limited by toxicity. Because ethnicity has been reported to affect clozapine metabolism, we compared its steady state pharmacokinetics in New Zealand Maori and European patients. Clozapine and norclozapine steady state bioavailability was assessed over 24h under fasting and fed conditions in 12 Maori and 16 European patients treated for chronic psychotic illnesses with stable once-daily clozapine doses. Plasma clozapine and norclozapine concentrations were assessed using liquid chromatography with tandem mass spectrometry; pharmacokinetic parameters were calculated using standard non-compartmental methods, and compared using unpaired t-tests. Mean pharmacokinetic parameters (AUC, C max and C min ) for clozapine and norclozapine were virtually identical in Maori and European subjects, under both fed and fasted conditions. Clozapine bioavailability does not vary between Maori and European patients, and thus does not need to be considered in prescribing decisions. Additional studies are needed to identify if there are differences between Maori and European populations for drugs metabolized by other enzyme pathways. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Maori tribal organisations in New Zealand history: From neglect to recognition, and the implications for the assimilation policy

    NARCIS (Netherlands)

    Meijl, A.H.M. van

    2003-01-01

    In New Zealand there has been a remarkable shift in government policy towards Maori tribes since the mid-1980s. Although the colonial history of the country is characterized by a consistent neglect of the tribal principle of Maori socio-political organisation, recently the government has gradually

  14. The Impact of Policy and Legislation on Maori Children with Special Needs in Aotearoa/New Zealand

    Science.gov (United States)

    Fortune, Kiri

    2013-01-01

    The purpose of this article is to review literature related to the impact of policy and legislation on Maori children with special needs. The historical perceptions of disability for Maori will be discussed and the impacts of western influences and policy will be reviewed. The article investigates relevant studies and literature, both national and…

  15. In search of Mahutonga: a possible supernova recorded in Maori astronomical traditions?

    Science.gov (United States)

    Green, David A.; Orchiston, Wayne

    Maori astronomical traditions refer to Mahutonga, which can be interpreted as a possible record of a southern supernova (SN) in or near Crux. A search for any known "young" supernova remnants in this region does not reveal any obvious candidate to associate with this possible supernova. Relaxing the positional constraint somewhat, the SN of A.D. 185 near a Centauri is nearby. If this is associated with Mahutonga, then the Maori term must be a relic of an earlier Proto-Polynesian record.

  16. Maori in Partnership: A Peer Mentoring Model for Tertiary Indigenous Staff in New Zealand

    Science.gov (United States)

    Kensington-Miller, Barbara; Ratima, Matiu

    2015-01-01

    This article presents a professional development programme which brought an indigenous minority group of tertiary staff together. We describe a peer-mentoring model, piloted in 2009 at The University of Auckland, New Zealand with university staff in order to promote staff advancement. The participants were all Maori, the indigenous people of New…

  17. Voice and Biliteracy in Indigenous Language Revitalization: Contentious Educational Practices in Quechua, Guarani, and Maori Contexts

    Science.gov (United States)

    Hornberger, Nancy H.

    2006-01-01

    This article considers instances of biliterate educational practice in contexts of indigenous language revitalization involving Quechua in the South American Andes, Guarani in Paraguay, and Maori in Aotearoa/New Zealand. In these indigenous contexts of sociohistorical and sociolinguistic oppression, the implementation of multilingual language…

  18. The Effect of Indigenous Politics on English Language Provision in New Zealand's Maori Schools

    Science.gov (United States)

    Rata, Elizabeth; Tamati, Tauwehe

    2013-01-01

    An ambivalence characterising the provision of English language instruction in New Zealand's Maori schools is traced to the establishment of the schools in the recent period of biculturalism and retribalisation, and to the role of the schools in indigenous ideology. The article discusses the effects of the ambivalence on English language provision…

  19. Maori Wellbeing and Being-in-the-World: Challenging Notions for ...

    African Journals Online (AJOL)

    Psychological research and practice in New Zealand has a long history of a positivist inspired epistemology and a pragmatic evidence-based approach to therapeutic treatment. There is a growing realization that a more meaningful interface between research and practice is required to accommodate indigenous Maori ...

  20. Ko Wai Au? Who Am I? Examining the Multiple Identities of Maori Youth

    Science.gov (United States)

    Faircloth, Susan C.; Hynds, Anne; Jacob, Helen; Green, Clint; Thompson, Patrick

    2016-01-01

    In this paper, we present preliminary findings from a unique collaborative research project involving six Deaf Maori rangatahi (youth) in Tamaki Makaurau (Auckland), Aotearoa New Zealand. This study utilized kaupapa whanau (research family) protocols, established in consultation with two cultural advisory groups within New Zealand and the young…

  1. The Poukai ceremony of the Maori King Movement: An ethnohistorical interpretation

    NARCIS (Netherlands)

    Meijl, A.H.M. van

    2009-01-01

    The poukai is a ceremonial gathering held on 28 days a year at different Marae [1] or ceremonial centres supporting the K ngitanga, or Maori King Movement, which is largely based within the Tainui confederation of tribes in the Waikato region of New Zealand's North Island. The K ngitanga was

  2. Hospitalizations for Pandemic (H1N1) 2009 among Maori and Pacific Islanders, New Zealand

    Science.gov (United States)

    Verrall, Ayesha; Norton, Katherine; Rooker, Serena; Dee, Stephen; Olsen, Leeanne; Tan, Chor Ee; Paull, Sharon; Allen, Richard

    2010-01-01

    Community transmission of influenza A pandemic (H1N1) 2009 was followed by high rates of hospital admissions in the Wellington region of New Zealand, particularly among Maori and Pacific Islanders. These findings may help health authorities anticipate the effects of pandemic (H1N1) 2009 in other communities. PMID:20031050

  3. 'It's whanaungatanga and all that kind of stuff': Maori cancer patients' experiences of health services

    Directory of Open Access Journals (Sweden)

    Slater T

    2013-12-01

    Full Text Available INTRODUCTION: There are unacceptable ethnic differences in cancer survival in Aotearoa/New Zealand. For people with cancer, quality of life and survival are shaped by access to care, but research on Maori access to, and through, cancer care is limited. Internationally, research has shown that primary care plays an important role in providing patient-centred, holistic care and information throughout the cancer care journey. Additionally, Maori health providers provide practical support and facilitate access to all levels of health care. Here we describe the cancer journeys of Maori patients and whanau and identify factors that may facilitate or inhibit access to and through cancer care services. METHODS: Twelve Maori patients affected by cancer and their whanau (family in the lower North Island took part in face-to-face semi-structured interviews exploring their experiences of cancer screening, diagnosis, treatment, survival and palliative care. FINDINGS: Three key areas were identified that impacted upon the cancer care journey: the experience of support; continuity of care; and the impact of financial and geographic determinants. CONCLUSION: Primary care plays a key role in support and continuity of care across the cancer journey. Alongside interpersonal rapport, a long-term relationship with a primary health provider facilitated a more positive experience of the cancer care journey, suggesting that patients with a 'medical home' are happier with their care and report less problems with coordination between services. Positive, longstanding relationships with general practitioners and Maori health providers assisted patients and whanau with the provision and understanding of information, alongside practical support.

  4. A Sense of Deja Vu across the Tasman? What Australians Might Learn from the New Zealand Experience with the Te Kotahitanga Professional Development Programme

    Science.gov (United States)

    Openshaw, Roger

    2007-01-01

    Throughout Australasia, indigenous educational issues remain a subject of considerable debate. In New Zealand, Maori underachievement in education has long been a matter of widespread concern. Currently the most highly visible professional development programme now operating in New Zealand mainstream secondary schools, Te Kotahitanga claims to…

  5. Encoding Context-Sensitivity in Reo into Non-Context-Sensitive Semantic Models (Technical Report)

    NARCIS (Netherlands)

    S.-S.T.Q. Jongmans (Sung-Shik); , C. (born Köhler, , C.) Krause (Christian); F. Arbab (Farhad)

    2011-01-01

    textabstractReo is a coordination language which can be used to model the interactions among a set of components or services in a compositional manner using connectors. The language concepts of Reo include synchronization, mutual exclusion, data manipulation, memory and context-dependency.

  6. Re-Os geochronology of a Mesoproterozoic sedimentary succession, Taoudeni basin, Mauritania: Implications for basin-wide correlations and Re-Os organic-rich sediments systematics

    Science.gov (United States)

    Rooney, Alan D.; Selby, David; Houzay, Jean-Pierre; Renne, Paul R.

    2010-01-01

    The exceptionally well-preserved sedimentary rocks of the Taoudeni basin, NW Africa represent one of the world's most widespread (> 1 M km 2) Proterozoic successions. Hitherto, the sedimentary rocks were considered to be Mid Tonian based on Rb-Sr illite and glauconite geochronology of the Atar Group. However, new Re-Os organic-rich sediment (ORS) geochronology from two drill cores indicates that the Proterozoic Atar Group is ˜ 200 Ma older (1107 ± 12 Ma, 1109 ± 22 Ma and 1105 ± 37 Ma). The Re-Os geochronology suggests that the Rb-Sr geochronology records the age of diagenetic events possibly associated with the Pan African collision. The new Re-Os geochronology data provide absolute age constraints for recent carbon isotope chemostratigraphy which suggests that the Atar Group is Mesoproterozoic and not Neoproterozoic. The new Re-Os ORS geochronology supports previous studies that suggest that rapid hydrocarbon generation (flash pyrolysis) from contact metamorphism of a dolerite sill does not significantly disturb the Re-Os ORS systematics. Modelled contact conditions suggest that the Re-Os ORS systematics remain undisturbed at ˜ 650 °C at the sill/shale contact and ≥ 280 °C 20 m from the sill/shale contact. Moreover, the Re-Os geochronology indicates that the West African craton has a depositional history that predates 1100 Ma and that ORS can be correlated on a basin-wide scale. In addition, the Re-Os depositional ages for the ORS of the Taoudeni basin are comparable to those of ORS from the São Francisco craton, suggesting that these cratons are correlatable. This postulate is further supported by identical Os i values for the Atar Group and the Vazante Group of the São Francisco craton.

  7. Towards Using Reo for Compliance-Aware Business Process Modeling

    Science.gov (United States)

    Arbab, Farhad; Kokash, Natallia; Meng, Sun

    Business process modeling and implementation of process supporting infrastructures are two challenging tasks that are not fully aligned. On the one hand, languages such as Business Process Modeling Notation (BPMN) exist to capture business processes at the level of domain analysis. On the other hand, programming paradigms and technologies such as Service-Oriented Computing (SOC) and web services have emerged to simplify the development of distributed web systems that underly business processes. BPMN is the most recognized language for specifying process workflows at the early design steps. However, it is rather declarative and may lead to the executable models which are incomplete or semantically erroneous. Therefore, an approach for expressing and analyzing BPMN models in a formal setting is required. In this paper we describe how BPMN diagrams can be represented by means of a semantically precise channel-based coordination language called Reo which admits formal analysis using model checking and bisimulation techniques. Moreover, since additional requirements may come from various regulatory/legislative documents, we discuss the opportunities offered by Reo and its mathematical abstractions for expressing process-related constraints such as Quality of Service (QoS) or time-aware conditions on process states.

  8. Neutron experiment for the Re/Os cosmochronometer

    International Nuclear Information System (INIS)

    Segawa, M.; Masaki, T.; Temma, Y.; Nagai, Y.; Shima, T.; Makii, H.; Mishima, K.; Ueda, H.; Igashira, M.; Ohsaki, T.; Shizuma, Toshiyuki; Hayakawa, Takehito

    2005-01-01

    We should clarify several problems for the Re-Os pair to be used as one of the good cosmochronometers. First, since 187 Os is formed and depleted by sequential neutron capture in stars, the effects should be corrected. Second, 187 Os is depleted by the neutron capture process through the excited state at 10 keV. It is very important to find a proper way to correct for the s-process contribution in deducing the age of the Galaxy. In order to correct for the effect mentioned above and to determine the age of the universe, we are planning to measure the neutron capture cross section of the first excited state (E excited =10 keV) of 187 Os, which is one of the key parameters in deducing the age of the Galaxy using the Re-Os cosmochronometer. In order to deduce the cross section we are preparing various detectors using a newly developed experimental method. In the present paper I briefly describe our experimental methods to accurately determine the neutron capture cross section of the first excited state of 187 Os. (author)

  9. Investigating antenatal nutrition education preferences in South-East Queensland, including Maori and Pasifika women.

    Science.gov (United States)

    Cruickshank, Andrea; Porteous, Helen E; Palmer, Michelle A

    2017-11-11

    Little is reported about the nutrition-related needs and preferences of women seeking maternity services, particularly Maori and Pasifika (M&P) women who have higher chronic disease rates in Queensland. Nutrition-related knowledge, needs, behaviours and education preferences were compared between women of M&P ancestry and non-Maori and Pasifika women (NMP). Women (≥18 years) admitted to the postnatal ward were surveyed. Anthropometry, dietary quality, nutrition education preferences, country of birth and ancestry were collected. Analysis included chi-squared and t-tests. The survey was completed by 399 eligible women. Country of birth data suggested 4% of respondents were Pasifika and failed to separately identify New Zealand Maori, whereas 18% of respondents (n=73) reported M&P ancestry. Descriptors were similar between groups (28±5 years; 91% any breastfeeding; 18% gestational diabetes mellitus; p>0.05). However M&P women were less often university educated (M&P:6(9%); NMP:71(22%), p2 children (M&P: 30(54%); NMP:70(30%), p75%) women did not know their recommended weight gain. Many respondents reported inadequate intake of vegetables (95%), fruit (29%) and dairy (69%) during pregnancy. Two-fifths (38-41%) reported interest in perinatal nutrition education, with topics including healthy eating postpartum. Findings enable targeted service delivery according to women's preferences. Collecting ancestral and maternal data to facilitate the provision of appropriate nutrition education may be critical for achieving optimal maternal outcomes in Maori and Pasifika women. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

  10. Establishing the date of Maori environmental impact in New Zealand through pollen analysis and radiocarbon dating

    Energy Technology Data Exchange (ETDEWEB)

    McGlone, M.S.; Wilmshurst, J.M. [Landcare Research, Lincoln, (New Zealand)

    1997-12-31

    Full text: Over the last decade there has been an intense debate about whether New Zealand prehistory is long ( > 1500 years) or short ( < 800 years). Pollen and charcoal analyses have played a key role in this debate by helping to pinpoint the transition from relatively undisturbed environments to those deforested by anthropogenic fires. Problems with in situ contamination, reworking of sediments, confusion of natural with anthropogenic impacts, and different theoretical expectations of growth, spread and impact of early Maori populations have led to disparate conclusions. We review pollen based studies carried out on a variety of fossil sites, including peat bogs, swamps, estuaries and lakes, and contribute new results. Different sedimentary environments show varying susceptibilities to contamination and have resulted in a wide spread of ages for initial Maori impact. Datable materials least susceptible to contamination by old or young carbon are pure peat and macrofossils, whereas lake, swamp and silty sediments are most susceptible. Analysis of the radiocarbon ages obtained for the start of Maori deforestation show that ages falling in the `long` prehistory period are exclusively derived from lake sediments and swamps. In contrast, the bulk of the ages falling in the `short` prehistory period are from pure peat and selected plant fragments. We conclude from our analysis of radiocarbon ages for pollen based deforestation that the first evidence of Maori environmental impact began about 700-550 calendar years BP (1250-1400 AD). Finer age resolution is limited by dating techniques, site limitations and the uncertainty associated with identifying the first signs of human impact. The period we have identified corresponds with the oldest dated archaeological sites and supports the short prehistory hypothesis. We discuss how to distinguish reliable fossil sites from those that have a high risk of giving misleading results.

  11. Establishing the date of Maori environmental impact in New Zealand through pollen analysis and radiocarbon dating

    International Nuclear Information System (INIS)

    McGlone, M.S.; Wilmshurst, J.M.

    1997-01-01

    Full text: Over the last decade there has been an intense debate about whether New Zealand prehistory is long ( > 1500 years) or short ( < 800 years). Pollen and charcoal analyses have played a key role in this debate by helping to pinpoint the transition from relatively undisturbed environments to those deforested by anthropogenic fires. Problems with in situ contamination, reworking of sediments, confusion of natural with anthropogenic impacts, and different theoretical expectations of growth, spread and impact of early Maori populations have led to disparate conclusions. We review pollen based studies carried out on a variety of fossil sites, including peat bogs, swamps, estuaries and lakes, and contribute new results. Different sedimentary environments show varying susceptibilities to contamination and have resulted in a wide spread of ages for initial Maori impact. Datable materials least susceptible to contamination by old or young carbon are pure peat and macrofossils, whereas lake, swamp and silty sediments are most susceptible. Analysis of the radiocarbon ages obtained for the start of Maori deforestation show that ages falling in the 'long' prehistory period are exclusively derived from lake sediments and swamps. In contrast, the bulk of the ages falling in the 'short' prehistory period are from pure peat and selected plant fragments. We conclude from our analysis of radiocarbon ages for pollen based deforestation that the first evidence of Maori environmental impact began about 700-550 calendar years BP (1250-1400 AD). Finer age resolution is limited by dating techniques, site limitations and the uncertainty associated with identifying the first signs of human impact. The period we have identified corresponds with the oldest dated archaeological sites and supports the short prehistory hypothesis. We discuss how to distinguish reliable fossil sites from those that have a high risk of giving misleading results

  12. Engaging Maori in Biobanking and Genetic Research: Legal, Ethical, and Policy Challenges

    Directory of Open Access Journals (Sweden)

    Angela Beaton

    2015-06-01

    Full Text Available Publically funded biobanking initiatives and genetic research should contribute towards reducing inequalities in health by reducing the prevalence and burden of disease. It is essential that Maori and other Indigenous populations share in health gains derived from these activities. The Health Research Council of New Zealand has funded a research project (2012-2015 to identify Maori perspectives on biobanking and genetic research, and to develop cultural guidelines for ethical biobanking and genetic research involving biospecimens. This review describes relevant values and ethics embedded in Maori indigenous knowledge, and how they may be applied to culturally safe interactions between biobanks, researchers, individual participants, and communities. Key issues of ownership, privacy, and consent are also considered within the legal and policy context that guides biobanking and genetic research practices within New Zealand. Areas of concern are highlighted and recommendations of international relevance are provided. To develop a productive environment for "next-generation" biobanking and genomic research,"‘next-generation" regulatory solutions will be required.

  13. Comparison of Os-Os and Re-Os dating results of molybdenites

    International Nuclear Information System (INIS)

    Xie Zhi; Sun Weidong; Chen Jiangfeng

    2002-01-01

    Two molybdenite samples from the Middle-Low Reaches of the Yangtze River were dated by both Os-Os and Re-Os methods. Os-Os and Re-Os dating give identical age results for the two samples. An experiment of step distillation of Os-Os method suggests that no isotopic fractionation is observed between fractions obtained by the experiment. The results prove that the Os-Os method can avoid the problems in the Re-Os method, simplify the experimental procedure, give creditable age data, and have unique advantage that no quantitative extracting of Os is required

  14. Work of the Gods: Tatai Arorangi (Maori Astronomy)

    Science.gov (United States)

    Leather, Kay; Hall, Richard

    Knowledgeable elders of ancient times, and their descendants today, studied the heavens and the stars - such was matai whetu, study of the stars - to identify the heavenly bodies and their relationships to each other. The knowledge gained was arranged in whakapapa, genealogies. Recitation of the star names was known as tatai whetu; navigation across the seas was tatai aro rangi: finding the appropriate path by the stars. The maramataka, or literally moon calendar, and the seasons were determined by the heliacal rising (rising just before the Sun) of certain stars. Knowledge of their world was the tool the ancients used to order their lives. From the first twitch in Te Kore, which gave life, to the continuous flow of creation, carried in the waters of life, even unto the breath of life, which allows creatures to move under their own mana, all the universe shares the tapu and the mana of the gods.

  15. Território, redes técnicas e transporte turístico aéreo: notas para discussão de seu contexto atual

    Directory of Open Access Journals (Sweden)

    Jaciel Gustavo Kunz

    2017-01-01

    Full Text Available As redes técnicas organizam o território na atualidade. Entre as tipologias de redes técnicas está a de circulação de pessoas, que opera a partir de distintos modais, com destaque para o aéreo. Este incorpora os maiores avanços técnicos e a perspectiva de fluidez. O presente trabalho tem por objetivo analisar contribuições teóricas a respeito do tema “redes técnicas” associado ao estudo do objeto “transporte aéreo de passageiros/turistas”, sob o contexto brasileiro atual dessa atividade. Por meio de pesquisa bibliográfica e documental de caráter exploratório, utilizam-se conceitos-chave, sobretudo da Geografia, afetos ao transporte aéreo, aproximando-os da perspectiva do Turismo. Esses permitem uma síntese, a partir da qual é possível propor uma reflexão preliminar, apontando relações – como entre hierarquias da rede de transporte aéreo e da rede urbana – e, também, agenda de pesquisa futura voltadas a uma compreensão mais ampla do transporte turístico aéreo na conjuntura contemporânea brasileira e sul-americana, oferecendo subsídios à intervenção com vistas ao desenvolvimento.

  16. Bi-Cultural Aotearoa/New Zealand: Provision of Psychological Services to the Maori Population of Rural New Zealand: Combining Best Practice with Cultural Considerations

    Science.gov (United States)

    Little, Steven G.; Akin-Little, Angeleque; Johansen, Anita

    2013-01-01

    New Zealand is considered a bi-cultural country with both the majority European and the minority/indigenous Maori cultures are supposedly given equal weight within the psyche and policies of the country. In reality, however, individuals of Maori descent tend to be over-represented in negative socio-economic and educational dimensions. A higher…

  17. Interview with Eddie Reisch

    Science.gov (United States)

    Owen, Hazel

    2013-01-01

    Eddie Reisch is currently working as a policy advisor for Te Reo Maori Operational Policy within the Student Achievement group with the Ministry of Education in New Zealand, where he has implemented and led a range of e-learning initiatives and developments, particularly the Virtual Learning Network (VLN). He is regarded as one of the leading…

  18. Emergency Department Length of Stay for Maori and European Patients in New Zealand

    Directory of Open Access Journals (Sweden)

    David Prisk

    2016-06-01

    Full Text Available Introduction: Emergency department length of stay (ED LOS is currently used in Australasia as a quality measure. In our ED, Maori, the indigenous people of New Zealand, have a shorter ED LOS than European patients. This is despite Maori having poorer health outcomes overall. This study sought to determine drivers of LOS in our provincial New Zealand ED, particularly looking at ethnicity as a determining factor. Methods: This was a retrospective cohort study that reviewed 80,714 electronic medical records of ED patients from December 1, 2012, to December 1, 2014. Univariate and multivariate analyses were carried out on raw data, and we used a complex regression analysis to develop a predictive model of ED LOS. Potential covariates were patient factors, temporal factors, clinical factors, and workload variables (volume and acuity of patients three hours prior to and two hours after presentation by a baseline patient. The analysis was performed using R studio 0.99.467. Results: Ethnicity dropped out in the stepwise regression procedure; after adjusting for other factors, a specific ethnicity effect was not informative. Maori were, on average, younger, less likely to receive bloodwork and radiographs, less likely to go to our observation area, less likely to have a general practitioner, and more likely to be discharged and to self-discharge; all of these factors decreased their length of stay. Conclusion: Length of stay in our ED does not seem to be related to ethnicity alone. Patient factors had only a small impact on ED LOS, while clinical factors, temporal factors, and workload variables had much greater influence. [West J Emerg Med. 2017;17(4438-448.

  19. Emergency Department Length of Stay for Maori and European Patients in New Zealand.

    Science.gov (United States)

    Prisk, David; Godfrey, A Jonathan R; Lawrence, Anne

    2016-07-01

    Emergency department length of stay (ED LOS) is currently used in Australasia as a quality measure. In our ED, Maori, the indigenous people of New Zealand, have a shorter ED LOS than European patients. This is despite Maori having poorer health outcomes overall. This study sought to determine drivers of LOS in our provincial New Zealand ED, particularly looking at ethnicity as a determining factor. This was a retrospective cohort study that reviewed 80,714 electronic medical records of ED patients from December 1, 2012, to December 1, 2014. Univariate and multivariate analyses were carried out on raw data, and we used a complex regression analysis to develop a predictive model of ED LOS. Potential covariates were patient factors, temporal factors, clinical factors, and workload variables (volume and acuity of patients three hours prior to and two hours after presentation by a baseline patient). The analysis was performed using R studio 0.99.467. Ethnicity dropped out in the stepwise regression procedure; after adjusting for other factors, a specific ethnicity effect was not informative. Maori were, on average, younger, less likely to receive bloodwork and radiographs, less likely to go to our observation area, less likely to have a general practitioner, and more likely to be discharged and to self-discharge; all of these factors decreased their length of stay. Length of stay in our ED does not seem to be related to ethnicity alone. Patient factors had only a small impact on ED LOS, while clinical factors, temporal factors, and workload variables had much greater influence.

  20. Investigation of Maori ovens on the old Lyttelton waterfront (M36/229)

    International Nuclear Information System (INIS)

    Dodd, A.

    2012-01-01

    The Canterbury earthquakes of 2011 caused widespread damage in the historic Lyttelton town centre. One of the many casualties was the former Lyttelton post office building. Constructed in 1875, the building as well as the parcel of land on which it was constructed was deemed archaeological and an emergency archaeological authority was obtained by the Canterbury Earthquake Recovery Agency prior to the building and its foundations being removed. During the removal of the foundations in August 2011 archaeological deposits associated with pre-contact Maori occupation were encountered. (author)

  1. Which family--what therapy: Maori culture, families and family therapy in New Zealand.

    Science.gov (United States)

    Kumar, Shailesh; Dean, Peter; Smith, Barry; Mellsop, Graham W

    2012-04-01

    New Zealand is a relatively young and small country which has seen steady migration for nearly seven centuries. Despite a long history of rivalry and hostility between Maori and European values, the country has also seen some significant synergism between the two cultures. For the last three decades Asians have also migrated at a significant pace. The country faces the challenge of delivering quality mental health services to such cultures which are bifurcated in being socio-centric (Maori, Pacific Islanders and Asian total 32% combined) or ego-centric (European total 68%). Significant progress has been made in including families of the mentally ill in their treatment and care planning. Legislative requirements have been introduced for the family to be consulted in the treatment of those who are being compelled to receive psychiatric care under the Mental Health Act. Models of family therapy developed through innovation meeting the unique local needs or adaptation of existing models from overseas are being used. An overview of such family therapy modalities is presented.

  2. Phase diagrams of ZnTe-HgTe-Te and ZnTe-CdTe-HgTe-Te systems

    International Nuclear Information System (INIS)

    Andrukhiv, A.M.; Litvak, A.M.; Mironov, K.E.

    1992-01-01

    ZnTe-HgTe-Te system liquidus surface is investigated and solid solution layers are produced in this system by the method of liquid-phase epitaxy (LPE). The theoretical analysis of experimental and theoretical data allows to calculate the diagram of ZnTe-CdTe-HgTe-Te system fusibility. A significant effect of elastic stresses of the epitaxial layer, grown on CdTe substrate, on the process of LPE of solid solutions is established

  3. Recrystallization in a Freezing Tolerant Antarctic Nematode, Panagrolaimus davidi, and a Alpine Weta, Hemideina maori (Orthoptera; Stenopelmatidae)

    DEFF Research Database (Denmark)

    Ramløv, Hans; Wharton, David A.; Wilson, Peter W.

    1996-01-01

    The ability of haemolymph from the freezing tolerant weta,Hemideina maori,and supernatant from homogenates of the freezing tolerant nematodePanagrolaimus davidito inhibit the recrystallization of ice was examined using the “splat freezing” technique and annealing on a cryomicroscope stage...

  4. Re/Os cosmochronometer: measurement of neutron cross sections

    International Nuclear Information System (INIS)

    Mosconi, M.

    2007-01-01

    This experimental work is devoted to the improved assessment of the Re/Os cosmochronometer. The dating technique is based on the decay of 187 Re (t 1/2 =41.2 Gyr) into 187 Os and determines the age of the universe by the time of onset of nucleosynthesis. The nucleosynthesis mechanisms, which are responsible for the 187 Re/ 187 Os pair, provide the possibility to identify the radiogenic fraction of 187 Os exclusively by nuclear physics considerations. Apart from its radiogenic component, 187 Os can be synthesized otherwise only by the s process, which means that this missing fraction can be reliably determined and subtracted by proper s-process modeling. On the other hand, 187 Re is almost completely produced by the r process. The only information needed for the interpretation as a cosmic clock is the production rate of 187 Re as a function of time. The accuracy of the s-process calculations that are needed to determine the nucleosynthetic abundance of 187 Os depends on the quality of the neutron capture cross sections averaged over the thermal neutron spectrum at the s-process sites. Laboratory measurements of these cross sections have to be corrected for the effect of nuclear levels, which can be significantly populated at the high stellar temperatures during the s process. The neutron capture cross sections of 186 Os, 187 Os and 188 Os have been measured at the CERN n TOF facility in the range between 0.7 eV and 1 MeV. From these data, Maxwellian averaged cross sections have been determined for thermal energies from 5 to 100 keV with an accuracy around 4%, 3%, and 5% for 186 Os, 187 Os, and 188 Os, respectively. Since, the first excited state in 187 Os occurs at 9.75 keV, the cross section of this isotope requires a substantial correction for thermal population of low lying nuclear levels. This effect has been evaluated on the basis of resonance data derived in the (n, γ) experiments and by an improved measurements of the inelastic scattering cross section for

  5. Re/Os cosmochronometer: measurement of neutron cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Mosconi, M.

    2007-12-21

    This experimental work is devoted to the improved assessment of the Re/Os cosmochronometer. The dating technique is based on the decay of {sup 187}Re (t{sub 1/2}=41.2 Gyr) into {sup 187}Os and determines the age of the universe by the time of onset of nucleosynthesis. The nucleosynthesis mechanisms, which are responsible for the {sup 187}Re/{sup 187}Os pair, provide the possibility to identify the radiogenic fraction of {sup 187}Os exclusively by nuclear physics considerations. Apart from its radiogenic component, {sup 187}Os can be synthesized otherwise only by the s process, which means that this missing fraction can be reliably determined and subtracted by proper s-process modeling. On the other hand, {sup 187}Re is almost completely produced by the r process. The only information needed for the interpretation as a cosmic clock is the production rate of {sup 187}Re as a function of time. The accuracy of the s-process calculations that are needed to determine the nucleosynthetic abundance of {sup 187}Os depends on the quality of the neutron capture cross sections averaged over the thermal neutron spectrum at the s-process sites. Laboratory measurements of these cross sections have to be corrected for the effect of nuclear levels, which can be significantly populated at the high stellar temperatures during the s process. The neutron capture cross sections of {sup 186}Os, {sup 187}Os and {sup 188}Os have been measured at the CERN n TOF facility in the range between 0.7 eV and 1 MeV. From these data, Maxwellian averaged cross sections have been determined for thermal energies from 5 to 100 keV with an accuracy around 4%, 3%, and 5% for {sup 186}Os, {sup 187}Os, and {sup 188}Os, respectively. Since, the first excited state in {sup 187}Os occurs at 9.75 keV, the cross section of this isotope requires a substantial correction for thermal population of low lying nuclear levels. This effect has been evaluated on the basis of resonance data derived in the (n, {gamma

  6. Designing an Early Childhood Environment: A Community-Built Playscape on Matakana Island, New Zealand

    Science.gov (United States)

    Christie, Toni; Christie, Robin

    2011-01-01

    Across the mouth of the Tauranga Harbour lies a piece of paradise, Te Moutere o Matakana--Matakana Island. It is blessed with an ocean beach with white sand and a mean surf break, tidal flats, wetlands, fertile pasture, and a native and exotic forest. It is home to a maori language nest for the local children--Te Kohanga Reo o te Moutere o…

  7. Application of the modified PGW method for determining the smoking attributable fraction of deaths in New Zealand Maori, Pacific and non-Maori non-Pacific populations

    Directory of Open Access Journals (Sweden)

    Peter Sandiford

    2013-02-01

    Full Text Available BACKGROUND Preston, Glei and Wilmoth recently proposed a new method for estimating smoking-attributable mortality in high income countries and an improvement to the method was proposed by Rostron. The method greatly simplifies estimation of smoking attributable fractions but additional testing has been recommended to validate the approach. OBJECTIVE We apply the Rostron (PGW-R method to ethnic groups in New Zealand and compare the results with published estimates from other sources with the purpose of determining their consistency and exploring possible reasons for any divergence. METHODS Four different sources were identified with ethnic-specific estimates of smoking attributable mortality fractions (SAMFfor Maori, Pacific Island and European/Other ethnic groups in New Zealand for periods between 1995 and 1999. These employed a variety of direct and indirect estimation techniques. The results were compared with PGW-R method estimates for the same period and ethnic groups. RESULTS Although the PGW-R method produced SAMF estimates that were within 5Š of those derived using the Peto-Lopez method for the European/other and total populations (in males and females, there were significant discrepancies between them in the Maori and Pacific SAMF estimates. Results using direct methods from a census linkage study were inconsistent with both the Peto-Lopez and the PGW-R method. Seven possible explanations for these discrepancies were considered and discussed but none could fully account for the differences. CONCLUSIONS The results of this work raise questions not only about the validity of the PGW-R method, but also about the accuracy of the estimates derived from the Peto-Lopez and direct methods, at least in these populations. Further research should examine the applicability of the key assumptions of the PGW method. Other work to determine the effects of possible misclassification bias in the direct method estimates would also aid interpretation of

  8. Hydrocarbons dating by Re-Os method: experimental study of the Re-Os couple geochemical behaviour in oils during the evolution of a petroleum system

    International Nuclear Information System (INIS)

    Mahdaoui, Fatima

    2013-01-01

    The Re-Os radiogenic system is well adapted to the dating of oils and bitumen. However the meaning of the obtained age is ambiguous. This is mainly due to gaps in our knowledge of the geochemical behavior and the speciation of Re and Os in oils. Specifically, use of the Re-Os geo-chronometer requires an understanding of how Re-Os behavior can lead to the fulfillment of the conditions necessary for the development of an isochron. These conditions are: i) the isotopic homogenization of oils at the scale of a petroleum field ii) the fractionation of Re from Os so as to obtain samples with various Re/Os ratios iii) the closure of the system during the period of radiogenic ingrowth of the daughter isotope, that is, from the time of the event of interest to the present day. Experimental investigation of the organic geochemical behavior of Re and Os in oils under various conditions, designed as analogs of the different stages of petroleum generation and evolution, were performed in order to evaluate the use of the Re-Os system as a geo-chronometer in the context of a direct use on petroleum. The possibility of Re-Os fractionation resulting from asphaltene loss during oil evolution was investigated by sequential asphaltene precipitation in the laboratory. This study determined that Re and Os are mainly located in the most polar asphaltene fractions, that is, in the first to precipitate. This study also demonstrated that Re/Os ratios are not disturbed by asphaltene loss during the evolution of oils, unless this loss is unrealistically large. Thus asphaltene precipitation during migration and emplacement is not responsible for the Re/Os fractionation required for the use of the geo-chronometer. The possibility of metal transfer from formation waters to petroleum was studied by performing contact experiments between oils and aqueous solutions of Re and Os of various concentrations over a wide range of temperatures and for varying periods of time. This study demonstrated a

  9. Pressure-induced phase transitions in nanocrystalline ReO3

    International Nuclear Information System (INIS)

    Biswas, Kanishka; Muthu, D V S; Sood, A K; Kruger, M B; Chen, B; Rao, C N R

    2007-01-01

    Pressure-induced phase transitions in the nanocrystals of ReO 3 with an average diameter of ∼12 nm have been investigated in detail by using synchrotron x-ray diffraction and the results compared with the literature data of bulk samples of ReO 3 . The study shows that the ambient-pressure cubic I phase (space group Pm3-barm) transforms to a monoclinic phase (space group C 2/c), then to a rhombohedral I phase (space group R3-barc), and finally to another rhombohedral phase (rhombohedral II, space group R3-barc) with increasing pressure over the 0.0-20.3 GPa range. The cubic I to monoclinic transition is associated with the largest volume change (∼5%), indicative of a reconstructive transition. The transition pressures are generally lower than those known for bulk ReO 3 . The cubic II (Im3-bar) or tetragonal (P4/mbm) phases do not occur at lower pressures. The nanocrystals are found to be more compressible than bulk ReO 3 . On decompression to ambient pressure, the structure does not revert back to the cubic I structure

  10. The ionic conductivity and local environment of cations in Bi9ReO17

    International Nuclear Information System (INIS)

    Thompson, M.; Herranz, T.; Santos, B.; Marco, J.F.; Berry, F.J.; Greaves, C.

    2010-01-01

    The influence of temperature on the structure of Bi 9 ReO 17 has been investigated using differential thermal analysis, variable temperature X-ray diffraction and neutron powder diffraction. The material undergoes an order-disorder transition at ∼1000 K on heating, to form a fluorite-related phase. The local environments of the cations in fully ordered Bi 9 ReO 17 have been investigated by Bi L III - and Re L III -edge extended X-ray absorption fine structure (EXAFS) measurements to complement the neutron powder diffraction information. Whereas rhenium displays regular tetrahedral coordination, all bismuth sites show coordination geometries which reflect the importance of a stereochemically active lone pair of electrons. Because of the wide range of Bi-O distances, EXAFS data are similar to those observed for disordered structures, and are dominated by the shorter Bi-O bonds. Ionic conductivity measurements indicate that ordered Bi 9 ReO 17 exhibits reasonably high oxide ion conductivity, corresponding to 2.9x10 -5 Ω -1 cm -1 at 673 K, whereas the disordered form shows higher oxide ion conductivity (9.1x10 -4 Ω -1 cm -1 at 673 K). - Graphical abstract: The structure of Bi 9 ReO 17 is discussed and related to the ionic conductivity of the ordered and disordered forms.

  11. Eaglet property, southeastern British Columbia: Re-Os geochronology, sulphur isotopes, and thermobarometry

    Czech Academy of Sciences Publication Activity Database

    Hora, Z. D.; Stein, H.; Žák, Karel; Dobeš, P.

    2018-01-01

    Roč. 2017, č. 1 (2018), s. 157-166 ISSN 0381-243X Institutional support: RVO:67985831 Keywords : Eaglet deposit * MINFILE 093A 046 * fluorite * celestite * molybdenite * sulphur isotopes * Re-Os geochronology * fluid inclusion microthermobarometry Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology http://cmscontent.nrs.gov.bc.ca/geoscience/PublicationsCatalogue/Fieldwork/Documents/2017/P2018-1.pdf

  12. Passageiros com deficiência no transporte aéreo brasileiro: diferentes atores, perspectivas semelhantes

    Directory of Open Access Journals (Sweden)

    Talita Naiara Rossi da Silva

    Full Text Available Resumo As mudanças em relação ao entendimento da deficiência no mundo buscam a efetivação da inclusão social e a maior participação das pessoas com deficiência em todos os contextos e atividades. Entretanto, no transporte aéreo há inúmeras barreiras que podem dificultar a viagem dessas pessoas. Assim, este estudo busca compreender as experiências de passageiros com deficiência no transporte aéreo brasileiro, a partir das perspectivas de diferentes atores sociais, incluindo profissionais que atuam em associações, centros de referência em reabilitação, órgãos públicos e passageiros com deficiência usuários do transporte aéreo. Para desenvolvimento do estudo foram realizadas 20 entrevistas semiestruturadas entre 2012 e 2013. Os resultados indicaram que os passageiros com deficiência encontram inúmeras dificuldades no transporte aéreo ao longo de todo o processo de viagem, inclusive fatores associados aos aeroportos, às aeronaves e aos serviços e procedimentos das companhias aéreas. Sugere-se que projetos envolvendo os usuários sejam desenvolvidos, para que seja possível compreender as reais necessidades desses passageiros e desenvolver soluções que assegurem sua independência e segurança no uso do transporte.

  13. Preparation and certification of Re-Os dating reference materials: Molybdenites HLP and JDC

    Science.gov (United States)

    Du, A.; Wu, S.; Sun, D.; Wang, Shaoming; Qu, W.; Markey, R.; Stain, H.; Morgan, J.; Malinovskiy, D.

    2004-01-01

    Two Re-Os dating reference material molybdenites were prepared. Molybdenite JDC and molybdenite HLP are from a carbonate vein-type molybdenum-(lead)- uranium deposit in the Jinduicheng-Huanglongpu area of Shaanxi province, China. The samples proved to be homogeneous, based on the coefficient of variation of analytical results and an analysis of variance test. The sampling weight was 0.1 g for JDC and 0.025 g for HLP. An isotope dilution method was used for the determination of Re and Os. Sample decomposition and preconcentration of Re and Os prior to measurement were accomplished using a variety of methods: acid digestion, alkali fusion, ion exchange and solvent extraction. Negative thermal ionisation mass spectrometry and inductively coupled plasma-mass spectrometry were used for the determination of Re and 187Os concentration and isotope ratios. The certified values include the contents of Re and Os and the model ages. For HLP, the Re content was 283.8 ?? 6.2 ??g g-1, 187Os was 659 ?? 14 ng g-1 and the Re-Os model age was 221.4 ?? 5.6 Ma. For JDC, the Re content was 17.39 ?? 0.32 ng g-1, 187Os was 25.46 ?? 0.60 ng g-1 and the Re-Os model age was 139.6 ?? 3.8 Ma. Uncertainties for both certified reference materials are stated at the 95% level of confidence. Three laboratories (from three countries: P.R. China, USA, Sweden) joined in the certification programme. These certified reference materials are primarily useful for Re-Os dating of molybdenite, sulfides, black shale, etc.

  14. Evaluating the utility of hydrocarbons for Re-Os geochronology : establishing the timing of processes in petroleum ore systems

    Energy Technology Data Exchange (ETDEWEB)

    Selby, D.; Creaser, R.A. [Alberta Univ., Edmonton, AB (Canada). Dept. of Earth and Atmospheric Sciences

    2005-07-01

    Oil from 6 Alberta oil sands deposits were analyzed with a rhenium-osmium (Re-Os) isotope chronometer, an emerging tool for determining valuable age information on the timing of petroleum generation and migration. The tool uses molybdenite and other sulphide minerals to establish the timing and duration of mineralization. However, establishing the timing events of petroleum systems can be problematic because viable sulphides for the Re-Os chronometer are often not available. Therefore, the known presence of Re and Os associated with organic matter in black shale, a common source of hydrocarbons, may suggest that bitumen and petroleum common to petroleum systems may be utilised for Re-Os geochronology. This study evaluated the potential of the Re-Os isotopic system for geochronology and as an isotopic tracer for hydrocarbon systems. The evaluation was based on Re-Os isotopic analyses of bitumen and oil sands. Hydrocarbons formed from migrated oil in both Alberta oil sand deposits and a Paleozoic Mississippi Valley-type lead-zinc deposit contain significant Re and Os contents with high {sup 187}Re/{sup 188}Os and radiogenic {sup 187}Os/{sup 188}Os ratios suitable for geochronology. The oil from the 6 Alberta oil sand deposits yields Re-Os analyses with very high Re/{sup 188}Os ratios, and radiogenic Os isotopic compositions. Regression of the Re-Os data yields a date of 116 {+-} 27 Ma. This date plausibly represents the period of in situ radiogenic growth of {sup 187}Os following hydrocarbon migration and reservoir filling. Therefore, directly dating these processes, and this formation age corresponds with recent burial history models for parts of the Western Canada Sedimentary Basin. The very high initial {sup 187}Os/{sup 188}Os for this regression requires rocks much older than Cretaceous for the hydrocarbon source.

  15. An investigation of child restraint/seatbelt usage in motor vehicles by Maori in Northland New Zealand

    Science.gov (United States)

    Brewin, M; Peters, T

    2003-01-01

    Method: Observational surveys were conducted at the two main car parks (McDonald's and the largest supermarket) to determine the number of passengers restrained, the type of restraints, and correct use. Observations were restricted to those who were obviously Maori, based upon the local knowledge of the observer. In addition, face to face questionnaires were administered to Maori whanau/caregivers involved in the care of two or more children for more than three days a week. Results: A total of 788 participants were observed. Babies were those most likely to have all occupants restrained correctly (97%), followed by toddlers (66%), adults (56%), and school age children (48%); 138 interviews were conducted. Females (86%) were significantly more likely to ensure that all passengers were restrained on short journeys compared to males (67%; p<0.05). Respondents under 45 (80%) were significantly less likely to restrain child passengers compared to people aged 45 or older (91%; p<0.05). Discussion: This study highlights the problem that larger families in this study had in providing correct child restraints for all their children. PMID:12642567

  16. [Polymorphisms of the multiple drug resistance gene (MDR1) in Mapuche, Mestizo and Maori populations in Chile].

    Science.gov (United States)

    Wielandt, Ana María; Vollrath, Valeska; Chianale, José

    2004-09-01

    There are significant differences in drug responses among different ethnic groups. The multidrug transporter P-gp, encoded by the MDR1 gene, plays a key role in determining drug bioavailability, and an association between a polymorphism in exon 26 (C3435T) and lower P-gp expression has been found. The co-segregation of this polymorphism with the polymorphism in exon 12 (C1236T) and in exon 21 (G2677T/A) determines several MDR1 haplotypes in humans. To characterize the polymorphisms of exons 26, 21 and 12 of the MDR1 gene in different Chilean populations. Using a polymerase chain reaction and restriction fragment length polymorphism technique, we studied the allelic frequencies and the distribution of MDR1 haplotypes in 3 Chilean populations: Mestizo (n=104), Mapuche (n=96, living in the National Reservation of the Huapi Island, Ranico Lake) and Maori (n=52, living in Eastern Island). The frequency of the normal MDR1*1 haplotype, without mutations, was lower in Mapuches than in Mestizos or Maoris (p0.0.5), but lower than the frequencies reported in Caucasians or Asians (p<0.05). We found significant differences in the frequencies of genetic polymorphisms of the MDR1 gene in Chilean populations, related to the ethnic origins of our ancestors.

  17. Examining the Potential of Critical and Kaupapa Maori Approaches to Leading Education Reform in New Zealand's English-Medium Secondary Schools

    Science.gov (United States)

    Berryman, Mere; Egan, Margaret; Ford, Therese

    2017-01-01

    This paper discusses expectations, policies and practices that currently underpin education within the New Zealand context. It acknowledges the ongoing failure of this policy framework to positively influence reform for Indigenous Maori students in regular, state-funded schools and highlights the need for extensive change in the positioning and…

  18. An innovative team-based stop smoking competition among Maori and Pacific Island smokers: rationale and method for the study and its evaluation

    NARCIS (Netherlands)

    Glover, M.; Bosman, A.; Wagemakers, A.; Kira, A.; Paton, C.; Cowie, N.

    2013-01-01

    Maori and Pacific Island people have significantly higher smoking rates compared to the rest of the New Zealand population. The main aim of this paper is to describe how knowledge of Indigenous people’s practices and principles can be combined with proven effective smoking cessation support into a

  19. Utilización del transporte aéreo en el comercio exterior argentino

    OpenAIRE

    Lanfranconi Bobbio, Antonella

    2016-01-01

    Tesis (Maestría en Comercio Internacional) -- Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina, 2016. La utilización del modal aéreo para el transporte internacional de mercaderías presenta numerosos beneficios para las empresas que operan en el comercio internacional. Los pronósticos de las industrias especializadas y las organizaciones internacionales del área indican que en los próximos años este modal tendrá un gran crecimiento. La presente investigación anal...

  20. The way to overcome the difficulty in Re-Os dating of molybdenite

    International Nuclear Information System (INIS)

    Suzuki, Katsuhiko; Masuda, Akimasa

    1990-01-01

    When a molybdenite was dissolved and treated by the conventional chemical procedure, it was difficult to achieve the isotopic equilibrium between the 187 Os radiogenically accumulated in the molybdenite and 'common' Os added as a kind of internal standard, even after chemically complete decomposition. It is evident that this isotopic disequilibrium effect results in deterioration of Re-Os age for the molybdenite. A newly developed analytical technique employing a microwave digestion was found out to promote the isotopic equilibration of Os from two sources and to provide us with the ages concordant with those obtained by other geochronometers. (author)

  1. Shell model for REO{sub x} nanoclusters in amorphous SiO{sub 2}: charge trapping and electroluminescence quenching

    Energy Technology Data Exchange (ETDEWEB)

    Tiagulskyi, S.; Nazarov, A.; Tyagulskii, I.; Lysenko, V. [Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, Prospekt Nauki 41, 03028 Kiev (Ukraine); Rebohle, L.; Lehmann, J.; Skorupa, W. [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden Rossendorf e.V., POB 510119, 01314 Dresden (Germany)

    2012-06-15

    In this work charge trapping and electroluminescence (EL) quenching in rare-earth (RE) implanted SiO{sub 2} on Si as a function of injected charge into the dielectric were studied. The blocking of the luminescent REO{sub X} nanoclusters from the hot exciting electrons by negative charge trapping in a defect region (shell) located in the vicinity of the REO{sub X} nanocluster/SiO{sub 2} interface is considered as the main mechanism of EL quenching for small size (up to 10 nm) REO{sub X} nanoclusters. It is suggested that the increase of the nanoclusters size results in disordering of the SiO{sub 2} matrix but in a decrease of local blocking for excitation of the luminescent centers. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Espacios aéreos pulmonares anormales por TCAR Abnormal air-filled spaces in the lung with HRCT

    OpenAIRE

    Juan Carlos Spina (h); Josefina Medina; Lucrecia Cúneo; Federico Badano; Florencia Bambaci; Juan Carlos Spina

    2008-01-01

    Objetivo: El propósito de este trabajo es revisar y dar claves para el diagnóstico de las distintas entidades que se presentan como espacios aéreos pulmonares anormales. Material y métodos: Se analizaron en forma retrospectiva los archivos de TCAR de nuestra institución con diagnóstico de espacios aéreos pulmonares anormales. En todos los casos se evaluó la localización, número (único o múltiples), grosor parietal y alteraciones parenquimatosas y mediastínicas asociadas y se los agrupo de acu...

  3. Superconductivity in REO0.5F0.5BiS2 with high-entropy-alloy-type blocking layers

    Science.gov (United States)

    Sogabe, Ryota; Goto, Yosuke; Mizuguchi, Yoshikazu

    2018-05-01

    We synthesized new REO0.5F0.5BiS2 (RE: rare earth) superconductors with high-entropy-alloy-type (HEA-type) REO blocking layers. The lattice constant a systematically changed in the HEA-type samples with the RE concentration and the RE ionic radius. A sharp superconducting transition was observed in the resistivity measurements for all the HEA-type samples, and the transition temperature of the HEA-type samples was higher than that of typical REO0.5F0.5BiS2. The sharp superconducting transition and the enhanced superconducting properties of the HEA-type samples may indicate the effectiveness of the HEA states of the REO blocking layers in the REO0.5F0.5BiS2 system.

  4. Veículos aéreos não tripulados e sua inserção em espaço aéreo não segregado

    Directory of Open Access Journals (Sweden)

    Matheus Oliveira Santos

    2016-12-01

    Full Text Available Nos últimos anos, a sociedade assistiu ao crescimento do uso de veículos aéreos sem a presença de um piloto a bordo. Tais dispositivos são denominados Veículos Aéreos Não Tripulados pela Agência Nacional de Aviação Civil. Esses equipamentos despontam em um momento em que um grande número de empresas se mostra interessada em sua utilização com fins comerciais em razão da sua capacidade de múltipla utilização. Este artigo tem como objetivo discutir a sua inserção em espaço aéreo não segregado, onde se deslocará junto com aeronaves convencionais e ainda apresentar as características operacionais desses equipamentos, sua evolução histórica, os esforços e a preocupação das autoridades aeronáuticas para sua possível regulamentação e inserção no espaço aéreo brasileiro.

  5. Central obesity and risk for type 2 diabetes in Maori, Pacific and European young men in New Zealand

    International Nuclear Information System (INIS)

    Rush, E.; Laulu, M.S.; Mitchelson, E.; Plank, L.

    2002-01-01

    Thirty healthy male volunteers between the ages of 18 and 27 and of a wide range of fatness were recruited for this study. Equal numbers (10) self identified as belonging to each of the Maori Pacific and European ethnic groups. Originally it was intended that 90 men(30 in each group) should be measured but the cost and availability of the doubly-labelled water prevented this. Specific measurements undertaken included resting metabolic rate by indirect calorimetry, total energy expenditure over 14 days by the doubly-labelled water technique; total and regional body fat from dual-energy x-ray absorptiometry; anthropometry (body mass index, skinfold thicknesses and girths); fat and carbohydrate utilisation from respiratory quotients and from carbon-13 analysis of expired breath; and dietary intake of macronutrients. Glucose tolerance, insulin, thyroid hormone, leptin and blood lipid determinations were also performed. The groups did not differ significantly in BMI, height body mass or fat mass - but the European group had significantly lower subscapular to triceps skinfolds and fat free mass than the Maori and Pacific group. Resting metabolic rate adjusted for fat mass and fat free mass was not different among the groups. Carbon-13 in expired breath was positively correlated to the subscapular to triceps skinfold ratio and insulin. Reported intake of dietary fibre was negatively related to blood lipids and subscapular to triceps skinfold ratio. Central obesity showed strong associations with biochemical measures of Type 2 diabetes risk These findings emphasise the relationships between body composition and fat distribution with risk of diabetes independent of ethnicity. (author)

  6. Central obesity and risk for type 2 diabetes in Maori, Pacific and European young men in New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Rush, E; Laulu, M S [Department of Applied Science, Auckland Institute of Technology, Auckland (New Zealand); Mitchelson, E [Department of Nursing, Unitec Institute of Technology, Auckland (New Zealand); Plank, L [Department of Surgery, School of Medicine, University of Auckland, Auckland (New Zealand)

    2002-07-01

    Thirty healthy male volunteers between the ages of 18 and 27 and of a wide range of fatness were recruited for this study. Equal numbers (10) self identified as belonging to each of the Maori Pacific and European ethnic groups. Originally it was intended that 90 men(30 in each group) should be measured but the cost and availability of the doubly-labelled water prevented this. Specific measurements undertaken included resting metabolic rate by indirect calorimetry, total energy expenditure over 14 days by the doubly-labelled water technique; total and regional body fat from dual-energy x-ray absorptiometry; anthropometry (body mass index, skinfold thicknesses and girths); fat and carbohydrate utilisation from respiratory quotients and from carbon-13 analysis of expired breath; and dietary intake of macronutrients. Glucose tolerance, insulin, thyroid hormone, leptin and blood lipid determinations were also performed. The groups did not differ significantly in BMI, height body mass or fat mass - but the European group had significantly lower subscapular to triceps skinfolds and fat free mass than the Maori and Pacific group. Resting metabolic rate adjusted for fat mass and fat free mass was not different among the groups. Carbon-13 in expired breath was positively correlated to the subscapular to triceps skinfold ratio and insulin. Reported intake of dietary fibre was negatively related to blood lipids and subscapular to triceps skinfold ratio. Central obesity showed strong associations with biochemical measures of Type 2 diabetes risk These findings emphasise the relationships between body composition and fat distribution with risk of diabetes independent of ethnicity. (author)

  7. Temporal evolution of mineralization events in the Bohemian Massif inferred from the Re-Os geochronology of molybdenite

    Czech Academy of Sciences Publication Activity Database

    Ackerman, Lukáš; Haluzová, Eva; Creaser, R. A.; Pašava, J.; Veselovský, F.; Breiter, Karel; Erban, V.; Drábek, M.

    2017-01-01

    Roč. 52, č. 5 (2017), s. 651-662 ISSN 0026-4598 R&D Projects: GA ČR GA13-15390S Institutional support: RVO:67985831 Keywords : Re-Os * geochronology * molybdenite * Bohemian Massif * granite Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 3.396, year: 2016

  8. Re-Os molybdenite dating of granite-related Sn-W-Mo mineralization at Hnilec, Gemeric Superunit, Slovakia

    International Nuclear Information System (INIS)

    Kohut, M.; Stein, H.

    2005-01-01

    Re-Os molybdenite ages from the exocontact of the Hnilec granite-greisen body provide temporal constraints for tin, tungsten and molybdenite mineralization in the Gemeric Superunit, Slovakia. Two molybdenite separates were taken from a representative sample of the Sn-W-Mo mineralization at Hnilec and their Re-Os ages of 262.2 ± 0.9 and 263.8 ± 0.8 Ma (2-sigma) are in excellent agreement. The obtained Re-Os molybdenite ages are similar to recent but less precise electron microprobe monazite (276 ± 13 Ma) and U-Pb single zircon (250 ± 18 Ma) ages from the Hnilec granite intrusion, supporting a granite-related greisen origin for the Sn-W-Mo mineralization. Our precise Re-Os molybdenite ages resolve the long time controversy over the timing of high-temperature mineralization in the Gemeric Superunit. These Permian ages eliminate suggestions of an Alpine age. The sulphur isotope composition of the studied molybdenite is δ 34 S (CDT) = 1.71 ± 0.2 %o and is consistent with a magmatic sulphur source. Field observations indicate the lack of a broad contact aureole in the vicinity of the Hnilec granite body. Shallow level granite emplacement in schistose host rocks was accompanied by alteration and formation of tin-tungsten greisen in the upper part of the granite and exocontact molybdenite mineralization, both commonly lacking in other granite bodies within the Gemeric Superunit. (author)

  9. El poder aéreo, instrumento decisivo para la resolución de las crisis del siglo XXI

    Directory of Open Access Journals (Sweden)

    Lombo López, Juan Antonio

    2002-02-01

    Full Text Available Aquí, su autor, el antiguo Jefe del estado Mayor del Aire (1997-2001, desarrolla de forma clara las características fundamentales del Poder Aéreo, sus cometidos y misiones principales y ciertas consideraciones en el empleo del mismo.
    Para ello, se da a conocer el papel que desempeña el Poder Aéreo como componente estratégico principal de la acción de los Ejércitos, estudiando los aspectos claves, político, estratégico y operativo de cualquier campaña militar, así como las características fundamentales, cometidos y misiones más usuales del Poder Aéreo.
    Todo lo anterior desde la óptica del puesto en el que le ha tocado vivir las actuaciones del Poder Aéreo en los últimos años, le lleva a la conclusión de que éste es un instrumento sumamente flexible y rentable para su utilización en cualquier tipo de crisis, desde las acciones humanitarias hasta los conflictos abiertos.

  10. Re-Os Isotopic Constraints on the Chemical Evolution and Differentiation of the Martian Mantle

    Science.gov (United States)

    Brandon, Alan D.; Walker, Richard J.

    2002-01-01

    The (187)Re-187Os isotopic systematics of SNC meteorites, thought to be from Mars, provide valuable information regarding the chemical processes that affected the Martian mantle, particularly with regard to the relative abundances of highly siderophile elements (HSE). Previously published data (Birck and Allegre 1994, Brandon et al. 2000), and new data obtained since these studies, indicate that the HSE and Os isotopic composition of the Martian mantle was primarily set in its earliest differentiation history. If so, then these meteorites provide key constraints on the processes that lead to variation in HSE observed in not only Mars, but also Earth, the Moon and other rocky bodies in the Solar System. Processes that likely have an effect on the HSE budgets of terrestrial mantles include core formation, magma ocean crystallization, development of juvenile crust, and the addition of a late veneer. Each of these processes will result in different HSE variation and the isotopic composition of mantle materials and mantle derived lavas. Two observations on the SNC data to present provide a framework for which to test the importance of each of these processes. First, the concentrations of Re and Os in SNC meteorites indicate that they are derived from a mantle that has similar concentrations to the Earth's mantle. Such an observation is consistent with a model where a chondritic late veneer replenished the Earth and Martian mantles subsequent to core formation on each planet. Alternative models to explain this observation do exist, but will require additional data to test the limitations of each. Second, Re-Os isotopic results from Brandon et al. (2000) and new data presented here, show that initial yos correlates with variations in the short-lived systems of (182)Hf- (182)W and (142)Sm-142Nd in the SNC meteorites (epsilon(sub W) and epsilon(sub 142Nd)). These systematics require an isolation of mantle reservoirs during the earliest differentiation history of Mars, and

  11. Insights into Andean metallogenesis from the perspective of Re-Os analyses of sulfides

    International Nuclear Information System (INIS)

    Mathur, R.; Ruiz, J.R; Munizaga, F.M

    2001-01-01

    The source of metals and duration of mineralization for ore deposits are basic issues used to describe the metallogenesis of an area. In order to address these fundamental issues in the Andean Cordillera, we chose to analyze Re-Os isotopes in sulfides from twelve porphyry copper ore deposits that are spatially and temporally separated. Re-Os concentrates in sulfide minerals, and can thus provide genetic information on the source of metals and the timing of mineralization. The advantage of using Re-Os isotopes is that genetic and geochronologic information is obtained directly from the sulfide ore mineral, rather than by inferring chemical relationships from possibly unrelated alteration silicates. In this study we use the source of Os in low concentration sulfides as a proxy for the source of base metals. Initial ratios greater than the chondritic mantle (∼0.13) serve as indication of a crustal source for Os and, by inference, other ore forming metals. Molybdenite contains orders of magnitude more Re than the common sulfides and effectively no initial radiogenic 187 Os (Luck and Allegre, 1982). Therefore, it can be used as a high-precision geochronometer (McCandless, 1994; Stein et al. 1997). Re-Os data from low concentration sulfides and chronologic data from high concentration molybdenites highlight important processes within and among these Andean deposits.The low concentration sulfides contain between 5-30 ppt Os and 1- 30 ppb Re. There are two samples of hydrothermal and magmatic magnetite from Escondida that contain slightly more Re and Os than the other sulfides reported. The molybdenites have 187 Os concentrations that range from 5-2000 ppb, and Re concentrations that range from 60-3600 ppm. Mathur et al. (2000) and Mathur (2000) highlighted a strong relationship between the copper tonnage in Andean ore deposits and the Os initial ratio of sulfide minerals. The larger deposits have sulfide minerals with lower initial Os ratios than the smaller, less

  12. Aislamiento acústico a ruido aéreo en acristalamientos de vidrio

    Directory of Open Access Journals (Sweden)

    Escuder Silla, E.

    2007-08-01

    Full Text Available In this paper, the Ookura & Saito model is applied to determine the Airborne Sound Insulation of glazing systems. In particular, the calculations that appear are for monolithic glasses of different thicknesses and laminated glasses from different types. There are different prediction models of the airborne acoustic behaviour of multilayer panels (and the laminated glasses can be considered like such. In all of them, the input data are the elastic constants and the loss factor. The monolithic glasses and the intermediate layer have been characterized according to different Standards. The results are compared with experimental measurements and data of the study of Marsh (1, obtaining a range of acceptable adjustment.

    En este artículo se aplica el modelo de Ookura & Saito para determinar el aislamiento acústico a ruido aéreo de sistemas constructivos basados en vidrios. En concreto, los cálculos que se presentan son para vidrios monolíticos de distintos espesores y para vidrios laminados de diferentes tipos. Existen diferentes modelos de predicción del comportamiento acústico a ruido aéreo de estructuras multicapa (y los vidrios laminados pueden considerarse como tales. En todos ellos, los datos de entrada son las constantes elásticas y el factor de pérdidas. Tanto los vidrios monolíticos como la capa intermedia se han caracterizado siguiendo diferentes normativas. Los resultados se comparan con medidas experimentales y con datos recogidos del estudio de Marsh (1, obteniéndose un grado de ajuste aceptable.

  13. Transporte de Café Cereza por Cable Aéreo de Gravedad

    Directory of Open Access Journals (Sweden)

    Parra Rodríguez Henry

    1989-12-01

    Full Text Available Con el fin de determinar los parámetros que gobiernan el transporte de café cereza por cable aéreo de gravedad, se construyó en el Centro Nacional de Investigaciones del Café “CENICAFE”, un banco de pruebas con longitud de 38.5m y de altura variable, para simular diferentes condiciones topográficas. En el trabajo se determinaron las mejores combinaciones de flecha-pendiente que no requieran de ningún dispositivo de frenado de una carga de 60kg, en el punto de descarga. Para pendientes mayores del 15% se debe implementar un sistema de amortiguación o control de la velocidad de las cargas. Flechas mayores al 6% no son recomendables para el sistema de transporte de café cereza por cable aéreo de gravedad, debido a la presencia indeseable de una onda en el cable que distorsiona el descenso de las cargas. Teniendo en cuenta los valores de flecha-pendiente anotados anteriormente, el diámetro mínimo del cable de acero recomendado para transpotadores de gravedad, debe de ser “para longitudes de 300m, por cada 120m adicionales de longitud se debe aumentar el diámetro en 1/8 de pulgada. La capacidad de transporte de café cereza en el banco de pruebas, enviando cargas de 60kg, fue mayor a 5000 kg de café cereza por hora para las diferentes combinaciones de flecha-pendiente experimentadas.

  14. Locating the global: culture, language and science education for indigenous students

    Science.gov (United States)

    McKinley, Elizabeth

    2005-02-01

    The international literature suggests the use of indigenous knowledge (IK) and traditional ecological knowledge (TEK) contexts in science education to provide motivation and self-esteem for indigenous students is widespread. However, the danger of alienating culture (as knowledge) from the language in which the worldview is embedded seems to have been left out of the philosophical and pedagogical debates surrounding research and comment in the field. This paper argues that one of the main ways in which indigenous knowledge systems will survive and thrive is through the establishment of programmes taught through indigenous languages so that a dialectal relationship between language and knowledge is established that continues to act as the wellspring. The article concludes by reviewing the situation in Aotearoa New Zealand with respect to the indigenous population, Maori, and the recent science education initiatives in te reo Maori (Maori language).

  15. Multiple episodes of mineralization revealed by Re-Os molybdenite geochronology in the Lala Fe-Cu deposit, SW China

    Science.gov (United States)

    Zhu, Zhimin; Tan, Hongqi; Liu, Yingdong; Li, Chao

    2018-03-01

    The Lala Fe-Cu deposit is one of the largest iron oxide-copper-gold (IOCG) deposits in the Kangdian copper belt, southwest China. The paragenetic sequence of the Lala deposit includes six hydrothermal stages: pre-ore pervasive Na alteration (I); magnetite stage with K-feldspar and apatite (II); polymetallic disseminated/massive magnetite-sulfide stage (III); banded magnetite-sulfide stage (IV); sulfide vein stage (V); and late quartz-carbonate vein stage (VI). Fifteen molybdenite separates from stages III to VI were analyzed for Re-Os dating. Our new Re-Os data, together with previous studies, identify four distinct hydrothermal events at the Lala deposit. Molybdenite from the stage III disseminated to massive chalcopyrite-magnetite ores yielded a weighted average Re-Os age of 1306 ± 8 Ma (MSWD = 1.1, n = 6) which represents the timing of main ore formation. Molybdenite from the stage IV-banded magnetite-chalcopyrite ores yielded a weighted average Re-Os age of 1086 ± 8 Ma (MSWD = 2.2, n = 7), i.e., a second ore-forming event. Molybdenite from the stage V sulfide veins yielded a weighted average Re-Os age of 988 ± 8 Ma (MSWD = 1.3, n = 7) which represents the timing of a third hydrothermal event. Molybdenite from the quartz-carbonate veins (stage VI) yielded a weighted average Re-Os age at 835 ± 4 Ma (MSWD = 0.66, n = 10) and documented the timing of a late hydrothermal event. Our results indicate that the Lala deposit formed during multiple, protracted mineralization events over several hundred million years. The first three Mesoproterozoic mineralization events are coeval with intra-continental rifting (breakup of the supercontinent Nuna) and share a temporal link to other IOCG-style deposits within the Kangdian Copper Belt, and the last Neoproterozoic hydrothermal event is coeval with the Sibao orogeny which culminated with the amalgamation of the Yangtze Block with the Cathaysia Block at 860-815 Ma.

  16. CH3-ReO3 on gamma-Al2O3: understanding its structure, initiation,and reactivity in olefin metathesis

    Energy Technology Data Exchange (ETDEWEB)

    Salameh, Alain; Joubert, Jerome; Baudouin, Anne; Lukens, Wayne; Delbecq, Francoise; Sautet, Philippe; Basset, Jean Marie; Coperet,Christophe

    2007-01-20

    Me-ReO3 on gamma-alumina: understanding the structure, theinitiation and thereactivity of a highly active olefin metathesiscatalyst Heterolytic splitting of the C-H bond of the methyl group ofCH3ReO3 on AlsO reactive sites of alumina as a way to generate the activesite of CH3ReO3 supported on gamma-Al203.

  17. Scientific communications: Re-Os sulfide (bornite, chalcopyrite, and pyrite) systematics of the carbonate-hosted copper deposits at ruby creek, southern brooks range, Alaska

    Science.gov (United States)

    Selby, D.; Kelley, K.D.; Hitzman, M.W.; Zieg, J.

    2009-01-01

    New Re-Os data for chalcopyrite, bornite, and pyrite from the carbonate-hosted Cu deposit at Ruby Creek (Bornite), Alaska, show extremely high Re abundances (hundreds of ppb, low ppm) and contain essentially no common Os. The Re-Os data provide the first absolute ages of ore formation for the carbonate-hosted Ruby Creek Cu-(Co) deposit and demonstrate that the Re-Os systematics of pyrite, chalcopyrite, and bornite are unaffected by greenschist metamorphism. The Re-Os data show that the main phase of Cu mineralization pre dominantly occurred at 384 ?? 4.2 Ma, with an earlier phase possibly at ???400 Ma. The Re-Os data are consistent with the observed paragenetic sequence and coincide with zircon U-Pb ages from igneous rocks within the Ambler metallogenic belt, some of which are spatially and genetically associated with regional volcanogenic massive sulfide deposits. The latter may suggest a temporal link between regional magmatism and hydrothermal mineralization in the Ambler district. The utility of bornite and chalcopyrite, in addition to pyrite, contributes to a new understanding of Re-Os geochronology and permits a refinement of the genetic model for the Ruby Creek deposit. ?? 2009 Society of Economices Geologists, Inc.

  18. Identificación de un vehículo aéreo no tripulado

    Directory of Open Access Journals (Sweden)

    Diamir De-Avila Rodríguez

    2012-02-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} El desarrollo de los vehículos aéreos ha influido considerablemente en la vida del hombre. Una tendencia actual es la investigación y desarrollo de vehículos aéreos no tripulados (Unmanned Aerial Vehicles, UAV, pues estos brindan grandes ventajas en disímiles tareas como el acceso a lugares remotos, reconocimiento, supervisión y vigilancia. Durante la confección de un autopiloto para estos vehículos, la obtención del modelo matemático es una tarea primordial, pues se requiere representar fielmente la dinámica del UAV para realizar un control eficiente sobre el mismo. Aunque se realizan muchos trabajos relacionados con el modelado analítico de los aviones no tripulados, la identificación del modelo a partir de datos es un método muy utilizado debido a que es muy difícil tener en consideración todas las interacciones y fenómenos físicos presentes en estos sistemas. En este trabajo se presenta diferentes modelos dinámicos de un avión autónomo de pequeño porte obtenidos aplicando varias técnicas de modelado e identificación de sistemas. En específico, se obtienen cuatro modelos con diferentes características: un modelo analítico, un modelo obtenido mediante una técnica de identificación clásica, un modelo nuero-borroso y un modelo borroso evolutivo. Finalmente, se expresan los resultados de los distintos modelos así como consideraciones sobre las utilidades de los mismos.

  19. A Re-Os Study of Depleted Trench Peridotites from Northern Mariana

    Science.gov (United States)

    Ghosh, T.; Snow, J. E.; Heri, A. R.; Brandon, A. D.; Ishizuka, O.

    2017-12-01

    Trench peridotites provide information about the influence of subduction initiation on the extent of mantle wedge melting. They preserve melting records throughout subduction history, and as a result, likely experience multiple melt extraction events leading to successive depletion of melt/fluid mobile major and trace elements. To track melting histories of trench peridotites, Re-Os and PGEs can be used as reliable tracers to constrain early melt extraction or re-fertilization events. The Izu-Bonin-Mariana arc, being the largest intra-oceanic subduction system, provides an excellent area to study the formation of supra-subduction zone mantle and crust. Residual peridotite (harzburgite and dunite) samples were collected by dredging from the landward slope of the northern Mariana Trench. The samples are serpentinized to various extents (typical of abyssal peridotites), leaving behind relict grains of spinel, enstatite and olivine embedded within a serpentine matrix along with occasional interstitial diopside. Major element analyses of primary minerals reveal a wide range of variations in Cr# of spinels from 0.31-0.85 indicating 16-20% of melt fraction with dunites apparently experiencing the highest amount of partial melting. For Re-Os and PGE geochemistry, samples with high amounts of spinel (>4 vol %) and variable Cr# were chosen. Initial results show that bulk rock 187Os/188Os ratios range from 0.1113 to 0.1272. All of the samples are sub-chondritic, but in some cases, they are more radiogenic than average abyssal peridotites. Os abundances vary from 1-9 ppb. Sub-chondritic values can be attributed to the samples having evolved from a Re-depleted mantle source indicating a previous melt-extraction event. The cpx-harzburgites, having lower Cr# ( 0.4) are more radiogenic than ultra depleted dunites (Cr# 0.8), which might indicate preferential removal of Os during an apparent higher degree of partial melting experienced by dunites. The higher 187Os/188Os ratios of

  20. Identificación y control de un Vehículo Aéreo no Tripulado tipo Quadcopter

    Directory of Open Access Journals (Sweden)

    Eduardo Giraldo Suarez

    2016-07-01

    Full Text Available En este artículo se aplica el algoritmo de identificación por mínimos cuadrados a un vehículo aéreo no tripulado tipo QuadCopter. El modelo se linealiza alrededor de un punto de operación y posteriormente se aplican controladores por realimentación de estados y LQR; este último demostró superioridad ante un controlador PID convencional.

  1. X-ray-absorption fine structure determination of pressure-induced bond-angle changes in ReO3

    International Nuclear Information System (INIS)

    Houser, B.; Ingalls, R.

    2000-01-01

    We report here on a Marquardt-type method to fit the x-ray absorption fine structure (XAFS) of ReO 3 . We find that, when the ambient-pressure structure of ReO 3 is used as a starting point, the pressure dependence of the angle of the Re-O-Re bond in ReO 3 is fairly straightforwardly and robustly determined using FEFF curved-wave, multiple-scattering programs and is accurate to about ±1.5 degree sign or better. We present an argument that XAFS and scattering experiments fundamentally differ in what they measure in the case of nearly linear atomic bridges. Focussed multiple-scattering paths involving the Re-O-Re bridge make a contribution to the XAFS spectrum that is sensitive to the rms deviation of oxygen from the [100]-type directions. Fits to simulated spectra back up our contention that for XAFS experiments the effective position of the oxygen atom is its rms displacement whether the average displacement is zero or not. (c) 2000 The American Physical Society

  2. Engaging indigenous Maori and inward migrating Asian professionals into a Pakeha (White European)-dominated Balint community in New Zealand.

    Science.gov (United States)

    McMichael, Timothy

    2018-01-01

    This inquiry began with two questions: How can the established predominately Pakeha/Caucasian (White European) Balint community in New Zealand more successfully engage both indigenous populations of both Maori and Pacifica origin into Balint work? And what is the existing Balint community doing to address the lack of Asian members of the Balint community in New Zealand, at a time when Asian health professionals are being recruited into the health sector at an increasingly high rate in comparison to White European entrants to the profession? These questions, and their preliminary answers presented here, invite the reader to reflect on both the challenges and opportunities in reaching out to groups different from our own. The author hopes readers may begin to see what can be done to allow new entrants to benefit from all that participation in Balint work offers while not losing sight of the uniqueness which each person can bring. It is hoped that sharing such questions and their subsequent explorations will help Balint leaders feel more confident in reaching out to a wider ethic and cultural mix within their local populations and encouraging them to enter the exciting world of the Balint group.

  3. Re-Os dating of molybdenites from Southern India: implication for Pan-African metallogeny

    International Nuclear Information System (INIS)

    Santosh, M.; Suzuki, Katsuhiko; Masuda, Akimasa

    1994-01-01

    Rhenium-osmium (Re-Os) dating of two molybdenite samples from the alkali granite and pegmatite of Ambalavayal in northern Kerala (S. India) yielded ages of 567 ±28 Ma and 566±77 Ma, respectively. These ages closely compare with the previously determined Rb-Sr whole rock age of 595±20 Ma Rb-Sr for granite, and K-Ar biotite age of 560±30 Ma for the pegmatite. Our study provides the first direct determination of the timing of ore mineralization associated with felsic magmatism in southern India, and reveals the fingerprints of a prominent Pan-African metallogenic event. This timing coincides with the formation of rare metal and gemstone-bearing pegmatites in different parts of southern India, Sri Lanka, Madagascar and East Antarctica. In most cases, the mineralizations are genetically related to felsic magmas emplaced along structural conduits, suggesting that the magmatism and metallogeny are related to deep-seated extension in the cratonized crustal segments of the Gondwana assembly. (author). 20 refs., 3 figs., 1 tab

  4. Extremely low Helicobacter pylori prevalence in North Sulawesi, Indonesia and identification of a Maori-tribe type strain: a cross sectional study.

    Science.gov (United States)

    Miftahussurur, Muhammad; Tuda, Josef; Suzuki, Rumiko; Kido, Yasutoshi; Kawamoto, Fumihiko; Matsuda, Miyuki; Tantular, Indah S; Pusarawati, Suhintam; Nasronudin; Harijanto, Paul N; Yamaoka, Yoshio

    2014-01-01

    Sulawesi in Indonesia has a unique geographical profile with assumed separation from Sundaland. Studies of Helicobacter pylori in this region are rare due to the region's rural location and lack of endoscopy equipment. Indirect methods are, therefore, the most appropriate for measuring H. pylori infection in these areas; with the disposable gastric brush test, we can obtain gastric juice as well as small gastric tissue samples for H. pylori culture. We investigated the prevalence of H. pylori infection and evaluated human migration patterns in the remote areas of North Sulawesi. We recruited a total of 251 consecutive adult volunteers and 131 elementary school children. H. pylori infection was determined by urine antibody test. A gastric brush test was used to culture H. pylori. We used next-generation and polymerase chain reaction based sequencing to determine virulence factors and multi-locus sequence typing (MLST). The overall H. pylori prevalence was only 14.3% for adults and 3.8% for children, and 13.6% and 16.7% in Minahasanese and Mongondownese participants, respectively. We isolated a single H. pylori strain, termed -Manado-1. Manado-1 was East Asian type cagA (ABD type), vacA s1c-m1b, iceA1 positive/iceA2 negative, jhp0562-positive/β-(1,3) galT-negative, oipA "on", and dupA-negative. Phylogenetic analyses showed the strain to be hspMaori type, a major type observed in native Taiwanese and Maori tribes. Our data support that very low H. pylori infection prevalence in Indonesia. Identification of hspMaori type H. pylori in North Sulawesi may support the hypothesis that North Sulawesi people migrated from north.

  5. Evaluation of the Good Start Program: a healthy eating and physical activity intervention for Maori and Pacific Islander children living in Queensland, Australia.

    Science.gov (United States)

    Mihrshahi, Seema; Vaughan, Lisa; Fa'avale, Nicola; De Silva Weliange, Shreenika; Manu-Sione, Inez; Schubert, Lisa

    2017-01-13

    Reducing the prevalence of obesity and chronic disease are important priorities. Maori and Pacific Islander communities living in Australia have higher rates of obesity and chronic disease than the wider Australian population. This study aims to assess the effectiveness of the Good Start program, which aims to improve knowledge, attitudes and practices related to healthy eating and physical activity amongst Maori and Pacific Islander communities living in Queensland. The intervention was delivered to children aged 6-19 years (N = 375) in schools by multicultural health workers. Class activities focused on one message each term related to healthy eating and physical activity using methods such as cooking sessions and cultural dance. The evaluation approach was a quantitative uncontrolled pre-post design. Data were collected each term pre- and post-intervention using a short questionnaire. There were significant increases in knowledge of correct servings of fruit and vegetables, knowledge of sugar and caffeine content of common sugar-sweetened drinks, recognition of the consequences of marketing and upsizing, and the importance of controlling portion size (all P well as the importance of physical activity for preventing heart disease (P emphasis on reducing intake of junk food may be beneficial. The study has shown that the Good Start Program was effective in engaging children from Maori and Pacific Island backgrounds and in improving knowledge, and some attitudes and practices, related to healthy eating and physical activity. The evaluation contributes valuable information about components and impacts of this type of intervention, and considerations relevant to this population in order to successfully change behaviours and reduce the burden of chronic disease.

  6. Absolute timing of sulfide and gold mineralization: A comparison of Re-Os molybdenite and Ar-Ar mica methods from the Tintina Gold Belt, Alaska

    Science.gov (United States)

    Selby, D.; Creaser, R.A.; Hart, C.J.R.; Rombach, C.S.; Thompson, J.F.H.; Smith, Moira T.; Bakke, A.A.; Goldfarb, R.J.

    2002-01-01

    New Re-Os molybdenite dates from two lode gold deposits of the Tintina Gold Belt, Alaska, provide direct timing constraints for sulfide and gold mineralization. At Fort Knox, the Re-Os molybdenite date is identical to the U-Pb zircon age for the host intrusion, supporting an intrusive-related origin for the deposit. However, 40Ar/39Ar dates from hydrothermal and igneous mica are considerably younger. At the Pogo deposit, Re-Os molybdenite dates are also much older than 40Ar/39Ar dates from hydrothermal mica, but dissimilar to the age of local granites. These age relationships indicate that the Re-Os molybdenite method records the timing of sulfide and gold mineralization, whereas much younger 40Ar/39Ar dates are affected by post-ore thermal events, slow cooling, and/or systemic analytical effects. The results of this study complement a growing body of evidence to indicate that the Re-Os chronometer in molybdenite can be an accurate and robust tool for establishing timing relations in ore systems.

  7. Rehabilitation of the Upper Extremity after Stroke: A Case Series Evaluating REO Therapy and an Auditory Sensor Feedback for Trunk Control

    Directory of Open Access Journals (Sweden)

    G. Thielman

    2012-01-01

    Full Text Available Background and Purpose. Training in the virtual environment in post stroke rehab is being established as a new approach for neurorehabilitation, specifically, ReoTherapy (REO a robot-assisted virtual training device. Trunk stabilization strapping has been part of the concept with this device, and literature is lacking to support this for long-term functional changes with individuals after stroke. The purpose of this case series was to measure the feasibility of auditory trunk sensor feedback during REO therapy, in moderate to severely impaired individuals after stroke. Case Description. Using an open label crossover comparison design, 3 chronic stroke subjects were trained for 12 sessions over six weeks on either the REO or the control condition of task related training (TRT; after a washout period of 4 weeks; the alternative therapy was given. Outcomes. With both interventions, clinically relevant improvements were found for measures of body function and structure, as well as for activity, for two participants. Providing auditory feedback during REO training for trunk control was found to be feasible. Discussion. The degree of changes evident varied per protocol and may be due to the appropriateness of the technique chosen, as well as based on patients impaired arm motor control.

  8. Re-Os isotope and platinum group elements of a FOcal ZOne mantle source, Louisville Seamounts Chain, Pacific ocean

    Science.gov (United States)

    Tejada, Maria Luisa G.; Hanyu, Takeshi; Ishikawa, Akira; Senda, Ryoko; Suzuki, Katsuhiko; Fitton, Godfrey; Williams, Rebecca

    2015-02-01

    The Louisville Seamount Chain (LSC) is, besides the Hawaiian-Emperor Chain, one of the longest-lived hotspot traces. We report here the first Re-Os isotope and platinum group element (PGE) data for Canopus, Rigil, and Burton Guyots along the chain, which were drilled during IODP Expedition 330. The LSC basalts possess (187Os/188Os)i = 0.1245-0.1314 that are remarkably homogeneous and do not vary with age. A Re-Os isochron age of 64.9 ± 3.2 Ma was obtained for Burton seamount (the youngest of the three seamounts drilled), consistent with 40Ar-39Ar data. Isochron-derived initial 187Os/188Os ratio of 0.1272 ± 0.0008, together with data for olivines (0.1271-0.1275), are within the estimated primitive mantle values. This (187Os/188Os)i range is similar to those of Rarotonga (0.124-0.139) and Samoan shield (0.1276-0.1313) basalts and lower than those of Cook-Austral (0.136-0.155) and Hawaiian shield (0.1283-0.1578) basalts, suggesting little or no recycled component in the LSC mantle source. The PGE data of LSC basalts are distinct from those of oceanic lower crust. Variation in PGE patterns can be largely explained by different low degrees of melting under sulfide-saturated conditions of the same relatively fertile mantle source, consistent with their primitive mantle-like Os and primordial Ne isotope signatures. The PGE patterns and the low 187Os/188Os composition of LSC basalts contrast with those of Ontong Java Plateau (OJP) tholeiites. We conclude that the Re-Os isotope and PGE composition of LSC basalts reflect a relatively pure deep-sourced common mantle sampled by some ocean island basalts but is not discernible in the composition of OJP tholeiites.

  9. Respuesta del Tumor Venéreo Transmisible Canino a Presentaciones de Vincristina de Patente y Genérica

    OpenAIRE

    Susana Miguel De la Cruz

    2015-01-01

    El objetivo del presente estudio fue comparar la respuesta de perros infectados naturalmente con el Tumor Venéreo Transmisible (TVTc) al tratamiento con vincristina comercial de patente y genérica. Se trabajó con 12 perros infectados naturalmente y con diagnóstico por citología y PCR. Los perros fueron asignados aleatoriamente a un tratamiento semanal con 0.025 mg/kg de vincristina de patente comercial o de tipo genérico, hasta que dos citologías consecutivas resultaran negativas. Se hicieron...

  10. Implementación del Sistema de Gestión y Control de Viajes Aéreos

    OpenAIRE

    Ferrer Pla, Ana

    2014-01-01

    Este proyecto consiste en la implementación de un sistema de gestión y control de viajes aéreos de una empresa mediante una herramienta de reservas en línea. Se trata de un proyecto real, que se ha llevado a cabo durante el segundo semestre del año 2013 en la empresa Ultramar, una naviera chilena cuya sede principal está en Santiago de Chile. Los objetivos del proyecto persiguen, por un lado, el ahorro en el presupuesto que la empresa destina a los viajes corporativos, y por otro, adoptar ...

  11. Central obesity and risk for type 2 diabetes in Maori, Pacific and European young men in New Zealand. Highlights and achievements

    International Nuclear Information System (INIS)

    Rush, E.

    2002-01-01

    Weight gain is associated with the incidence of Type 2 diabetes. Maori and Pacific people in New Zealand have a greater prevalence of obesity and Type 2 diabetes compared to NZ European people. We hypothesised that this difference is related to metabolic and fat distribution differences as previously demonstrated in a study of Polynesian and European women. Thirty healthy male volunteers between the ages of 18 and 27 years were selected for a wide range of fatness. Equal numbers, 10 in each group, self-identified as belonging to either the Maori, Pacific or European ethnic groups. Specific measurements undertaken included resting metabolic rate by indirect calorimetry; total energy expenditure over 14 days by the doubly-labelled water technique; total and regional body fat from dual-energy x-ray absorptiometry; anthropornetry (body mass index, skinfold thicknesses and girths); fat and carbohydrate utilisation from respiratory quotients and from carbon-13 analysis of expired breath; and dietary intake of macronutrients. Glucose tolerance, insulin, glycosylated haemoglobin, thyroid hormone, leptin and blood lipid determinations were also performed and HOMA and ISIO-120 indices calculated

  12. THE EFFECT OF SULPHURIC ACID CONCENTRATION ON SOLVENT EXTRACTION OF ReO4 - BY THE LONG-CHAIN ALIPHATIC TERTIARY AMINES AND ALCOHOLS

    Directory of Open Access Journals (Sweden)

    Aleksander G. Kasikov

    2010-06-01

    Full Text Available The effect of sulphuric acid concentration on solvent extraction of ReO4- by the long-chain aliphatic tertiary amines and alcohols in a wide range of H2SO4 concentrations in initial solutions is discussed. It has been established that the influence of the sulphuric acid concentration on rhenium solvent extraction is largely due to the extraction process mechanism. In the case of the anion-exchange mechanism, ReO4- is best extracted from weakly acidic solutions, whereas when the hydrate-solvate mechanism takes place – from solutions containing 4-7 mole/l H2SO4.

  13. Late Carboniferous porphyry copper mineralization at La Voluntad, Neuquén, Argentina: Constraints from Re-Os molybdenite dating

    Science.gov (United States)

    Garrido, Mirta; Barra, Fernando; Domínguez, Eduardo; Ruiz, Joaquin; Valencia, Victor A.

    2008-07-01

    The La Voluntad porphyry Cu-Mo deposit in Neuquén, Argentina, is one of several poorly known porphyry-type deposits of Paleozoic to Early Jurassic age in the central and southern Andes. Mineralization at La Voluntad is related to a tonalite porphyry from the Chachil Plutonic Complex that intruded metasedimentary units of the Piedra Santa Complex. Five new Re-Os molybdenite ages from four samples representing three different vein types (i.e., quartz-molybdenite, quartz-sericite-molybdenite and quartz-sericite-molybdenite ± chalcopyrite-pyrite) are identical within error and were formed between ~312 to ~316 Ma. Rhenium and Os concentrations range between 34 to 183 ppm and 112 to 599 ppb, respectively. The new Re-Os ages indicate that the main mineralization event at La Voluntad, associated to sericitic alteration, was emplaced during a time span of 1.7 ± 3.2 Ma and that the deposit is Carboniferous in age, not Permian as previously thought. La Voluntad is the oldest porphyry copper deposit so far recognized in the Andes and indicates the presence of an active magmatic arc, with associated porphyry style mineralization, at the proto-Pacific margin of Gondwana during the Early Pennsylvanian.

  14. O sul corpóreo: Trajeto de um corpo sociocultural ao corpo poético

    Directory of Open Access Journals (Sweden)

    Rocio del Carmen Tisnado Vargas

    2016-12-01

    Full Text Available Este artigo traz uma discussão sobre a metáfora do sul corpóreo, conceito o qual busca pensar a teoria do sociólogo Boaventura de Sousa Santos com as chamadas Epistemologias do Sul, como ponto de convergência com o fazer teatral, transferindo a metáfora do “sul” ao corpo do ator inserido na prática teatral. Apresentamos neste texto o paradigma de significações que traz consigo a metáfora, as afecções dos desdobramentos na dimensão social contemporânea e a produção de conhecimento desde a ótica de um pensamento “latino-americano”. Este conceito tem sua incubação e emerge como ideia central na investigação “Mergulho ao Sul Corpóreo: Trajeto de um corpo sociocultural ao corpo poético”, investigação em andamento idealizada pela autora.

  15. Re-Os isotope systematics of the Radio Hill Ni-Cu-PGE complex, West Pilbara Craton, Western Australia

    International Nuclear Information System (INIS)

    Frick, L.R.; McBride, J.S.

    1999-01-01

    Full text: The Radio Hill Complex is one of several layered mafic-ultramafic intrusions that were emplaced into the west Pilbara Craton at ca. 2.9 Ga. It is believed to be genetically related to other similar intrusions in the area which include the Munni Munni, Andover, Dingo and Maitland Complexes (Hoatson et al. 1999). The Radio Hill Complex is the only one of these intrusions to contain economic quantities of Ni and Cu at the present time. This relatively small intrusion (∼1200 m stratigraphic thickness) is divided into two zones, an upper gabbroic zone and a lower ultramafic zone, the base of which possesses massive magmatic sulfide mineralisation (pyrrhotite, pentlandite, chalcopyrite, magnetite). Re-Os isotopic data have been obtained for a suite of samples from underground, outcrop (gabbroic zone samples) and drill core. Os concentrations in the mineralised zone are very high, ranging from 19 to 191 ppb Os, with low Re/Os ratios ( 10,000), where R-factor is defined as the mass ratio of silicate magma to sulfide magma that it has equilibrated with. However, modelling of the Radio Hill ore system using Re, Os and PGE (Hoatson et al. 1992) concentrations suggest that the R-factor in the Radio Hill ore was low (100-900). Therefore, the initial Os isotopic composition of the ore should be radiogenic (high gOs >+500) if local crustal contamination triggered sulfide saturation. The slightly radiogenic initial Os isotopic composition suggests that the bulk parental magma was a crustally-contaminated magma. R-factor modelling further suggests that the parental magma to this intrusion was neither a basalt nor a pure komatiite, but more likely a contaminated komatiite (with a relatively high Os concentration). This agrees with the previous findings of Hoatson et al. (1992) who proposed a parental magma of siliceous high-magnesium basalt (SHMB) composition. Our Re-Os isotope modelling agrees with the trace elements, Nd and Sr isotope modelling of Hoatson et al. (1992

  16. Evaluation of the Good Start Program: a healthy eating and physical activity intervention for Maori and Pacific Islander children living in Queensland, Australia

    Directory of Open Access Journals (Sweden)

    Seema Mihrshahi

    2017-01-01

    Full Text Available Abstract Background Reducing the prevalence of obesity and chronic disease are important priorities. Maori and Pacific Islander communities living in Australia have higher rates of obesity and chronic disease than the wider Australian population. This study aims to assess the effectiveness of the Good Start program, which aims to improve knowledge, attitudes and practices related to healthy eating and physical activity amongst Maori and Pacific Islander communities living in Queensland. Methods The intervention was delivered to children aged 6–19 years (N = 375 in schools by multicultural health workers. Class activities focused on one message each term related to healthy eating and physical activity using methods such as cooking sessions and cultural dance. The evaluation approach was a quantitative uncontrolled pre-post design. Data were collected each term pre- and post-intervention using a short questionnaire. Results There were significant increases in knowledge of correct servings of fruit and vegetables, knowledge of sugar and caffeine content of common sugar-sweetened drinks, recognition of the consequences of marketing and upsizing, and the importance of controlling portion size (all P < 0.05. There was also increases in knowledge of physical activity recommendations (P < 0.001, as well as the importance of physical activity for preventing heart disease (P < 0.001 and improving self-esteem (P < 0.001. In terms of attitudes, there were significant improvements in some attitudes to vegetables (P = 0.02, and sugar-sweetened drinks (P < 0.05. In terms of practices and behaviours, although the reported intake of vegetables increased significantly (P < 0.001, the proportion of children eating discretionary foods regularly did not change significantly, suggesting that modifying the program with an increased emphasis on reducing intake of junk food may be beneficial. Conclusion The study has shown that the Good

  17. Efectos de la liberalización en la geografía del transporte aéreo en Colombia

    Directory of Open Access Journals (Sweden)

    Oscar Díaz Olariaga

    2016-01-01

    Full Text Available La geografía del transporte aéreo y del sistema aeroportuario colombiano se ha visto muy influenciada por el desarrollo que ha experimentado la industria a partir de su liberalización a principios de la década de los noventa. Las políticas públicas que siguieron a la liberalización de la industria contribuyeron a que, en primer lugar, la red aeroportuaria se modernizara y se expandiera a casi toda la geografía colombiana habitada, y en segundo lugar, dichas políticas propiciaron un dinámico desarrollo y crecimiento del movimiento de pasajeros aéreos a muchas de las regiones del país, generando una verdadera estructura de red del sistema de transporte aéreo. Este trabajo de investigación describe y analiza cómo la liberalización, a través de las políticas públicas, contribuyó, y lo siguen haciendo en la actualidad, a la configuración geográfica del transporte aéreo explicando además su desarrollo y dinámica.

  18. Sistema para sincronização e gerenciamento de fluxo de tráfego aéreo multi-agentes

    Directory of Open Access Journals (Sweden)

    Marcos Vinícius Pinheiro Dib

    2009-10-01

    Full Text Available

    Nesta pesquisa propõe-se um sistema para sincronização e gerenciamento de fluxo de tráfego aéreo que combina tecnologias de Inteligência Artificial – coordenação de Multi-Agentes, e computação distribuída sobre a Internet – Grid Computacional – cuja finalidade é otimizar o fluxo de tráfego aéreo, prevendo congestionamentos e racionalizando a utilização dos recursos dos aeroportos, sem contudo, ferir os princípios de segurança estabelecidos para a área de transportes aéreos. Para demonstrar o sistema desenvolvido, são descritos sua arquitetura, seus componentes e os relacionamentos entre eles, bem como os mecanismos de negociação necessários às tomadas de decisão. A título ilustrativo, é relatado um estudo de caso de planejamento tático, simulado a partir de informações do Aeroporto Internacional de São Paulo. A combinação das duas tecnologias, coordenação de Multi-Agentes e Grid Computacional, aplicada ao problema de gerenciamento do fluxo de tráfego aéreo apresenta perspectivas de tornar-se um tópico promissor para pesquisas futuras.

  19. Research On Technology Of Making Rare Earth Alloy Having Rare Earth Content ≽30% From Ore (≽40% REO) Using Aluminum Thermal Technology In Arc Furnace

    International Nuclear Information System (INIS)

    Ngo Xuan Hung; Ngo Trong Hiep; Tran Duy Hai; Nguyen Huu Phuc

    2014-01-01

    Arc furnace was used to smelt materials consisting of rare earth ore having rare earth content of ≽40% REO, aluminum as the reducing agent and additives. Rare earth alloy was obtained with rare earth metal content of more than 30%. (author)

  20. Inventário arbóreo-urbano do município de Salto de Pirapora, SP

    Directory of Open Access Journals (Sweden)

    Daniele Porto Benatti

    2012-10-01

    Full Text Available Este estudo teve por objetivo realizar o inventário arbóreo-urbano em 24 bairros do Município de Salto de Pirapora, SP, por meio da avaliação quali-quantitativa. Para tanto, foram obtidas informações relacionadas à: espécie arbórea, situação da copa e do tronco, orientação do tronco, fitossanidade, interceptação das raízes no passeio, necessidade de tratos silviculturais, altura total e altura da primeira bifurcação, assim como características do espaço viário. Foram registrados 868 indivíduos, dos quais 679 foram catalogados em 71 espécies arbóreas. A espécie de maior frequência foi Caesalpinia pluviosa, representando 13,6% do total, seguida de Ficus benjamin (10,4%, Lagerstroemia indica (5,0% e Terminalia catappa (4,8%. Quanto à condição do tronco, 68,8% dos indivíduos arbóreos não apresentaram problemas; 85,7% das árvores observadas possuíam orientação simpodial adequada; poucas árvores apresentavam danos relacionados à fitossanidade que poderiam interferir em sua integridade e, ou, longevidade; 69,6% não interferiam, de forma direta, na calçada; 32,8% das árvores necessitavam de podas por estarem acima da fiação elétrica; 0,5% necessitava de substituição; e 5,7% precisavam ser removidas. Com relação à altura total das árvores, 63,0% apresentavam crescimento menor que 5 m; e 65,3% com altura da primeira bifurcação do tronco inferior a 1,80 m. O Bairro Primavera destacou-se pelo maior número de árvores em sua urbanização. Em contrapartida, o Jardim Amélia apresentou apenas um indivíduo. Dessa forma, observou-se que cada bairro possuía sua particularidade, e ações de manutenção e enriquecimento, tanto relacionadas ao número de espécies quanto à quantidade de indivíduos, deveriam ser consideradas no planejamento urbano-arbóreo daquele município.

  1. Re-Os ages for Archean molybdenite and pyrite, Kuittila-Kivisuo, Finland and Proterozoic molybdenite, Kabeliai, Lithuania: Testing the chronometer in a metamorphic and metasomatic setting

    Science.gov (United States)

    Stein, H.J.; Sundblad, K.; Markey, R.J.; Morgan, J.W.; Motuza, G.

    1998-01-01

    Seven 187Re-187Os ages were determined for molybdenite and pyrite samples from two well-dated Precambrian intrusions in Fennoscandia to examine the sustainability of the Re-Os chronometer in a metamorphic and metasomatic setting. Using a new 187Re decay constant (1.666 x 10-11y-1) with a much improved uncertainty (±0.31%), we determined replicate Re-Os ages for molybdenite and pyrite from the Kuittila and Kivisuo prospects in easternmost Finland and for molybdenite from the Kabeliai prospect in southernmost Lithuania. These two localities contain some of the oldest and youngest plutonic activity in Fennoscandia and are associated with newly discovered economic Au mineralization (Ilomantsi, Finland) and a Cu-Mo prospect (Kabeliai, Lithuania). Two Re-Os ages for veinhosted Kabeliai molybdenite average 1486 ± 5 Ma, in excellent agreement with a 1505 ± 11 Ma U-Pb zircon age for the hosting Kabeliai granite pluton. The slightly younger age suggests the introduction of Cu-Mo mineralization by a later phase of the Kabeliai magmatic system. Mean Re-Os ages of 2778 ± 8 Ma and 2781 ± 8 Ma for Kuittila and Kivisuo molybdenites, respectively, are in reasonable agreement with a 2753 ± 5 Ma weighted mean U-Pb zircon age for hosting Kuittila tonalite. These Re-Os ages agree well with less precise ages of 2789 ± 290 Ma for a Rb-Sr whole-rock isochron and 2771 ± 75 Ma for the average of six Sm-Nd T(DM) model ages for Kuittila tonalite. Three Re-Os analyses of a single pyrite mineral separate, from the same sample of Kuittila pluton that yielded a molybdenite separate, provide individual model ages of 2710 ± 27, 2777 ± 28, and 2830 ± 28 Ma (Re = 17.4, 12.1, and 8.4 ppb, respectively), with a mean value of 2770 ± 120 Ma in agreement with the Kuittila molybdenite age. The Re and 187Os abundances in these three pyrite splits are highly correlated (r = 0.9994), and provide a 187Re-187Os isochron age of 2607 ± 47 Ma with an intercept of 21 ppt 187Os (MSWD = 1.1). It appears

  2. Waste form evaluation for RECl 3 and REO x fission products separated from used electrochemical salt

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; Pierce, David A.; Crum, Jarrod V.; Williams, Benjamin D.; Snyder, Michelle M. V.; Peterson, Jacob A.

    2018-04-01

    The work presented here is based off the concept that the rare earth chloride (RECl3) fission products mixture within the used electrorefiner (ER) salt can be selectively removed as RECl3 (not yet demonstrated) or precipitated out as REOCl through oxygen sparging (has been demonstrated). This paper presents data showing the feasibility of immobilizing a mixture of RECl3’s at 10 mass% into a TeO2-PbO glass and it shows that this same mixture of RECl3’s can be oxidized to REOCl at 300°C and then to REOx by 1200°C. When the REOx mixture is heated at temperatures >1200°C, the ratios of REOx’s change. The mixture of REOx was then immobilized in a LABS glass at a high loading of 60 mass%. Both the TeO2-PbO glass and LABS glass systems show good chemical durability. The advantages and disadvantages of tellurite and LABS glasses are compared.

  3. Application of a Genetic Algorithm in a Collaborative Process to Resolve Hydrology and Physical Reality with Both Western and Maori Cultural Values

    Science.gov (United States)

    Sheer, D.; Sheer, A.; Lebherz, S.

    2009-12-01

    Lakes Rotorua and Rotoiti are two sizeable, culturally and economically important lakes on the North Island of New Zealand. Rotorua outflows traverse the short Ohau Channel before entering Lake Rotoiti. Ohau channel flows are partially controlled by a stoplog structure. Rotoiti outflows to the Kaituna River are fully controlled by the Okere Gate structure. The structures are managed by Environment Bay of Plenty (EBOP), a government agency. Management objectives include maintaining minimum lake levels to support recreational boating, restricting maximum lake levels to avoid residential flooding, minimum instream flows below the lower lake to maintain aquatic ecosystems, limits on maximum releases to control erosion and prevent flooding. In addition, management seeks to provide for a minimum annual variation in lake levels to control the growth of aquatic plants in the littoral zone and to periodically expose beaches with important cultural value to the indigenous Maori population. The levels necessary to expose beaches may be lower than the minimum levels desired to support boating. Records of beach exposure are scant; the existence of beaches may depend on climate cycles. There is flow dependent recreational rafting below Okere Gates. This rafting is economically valuable, but is also contentious because the reach of Kaituna River flows through important Maori cultural areas, including grave sites. The Maoris have expressed a preference for replacing the Okere Gates with a fixed stepped weir, although the existing gates can be relatively easily operated to reproduce the flows over any of the fixed weir designs so far proposed. HydroLogics created a model of the two-lake system using its OASIS software system. The inflows to the lakes were estimated based on available historical flow and lake level data and on flow estimates derived from Mike-11 modeling of historical lake outlet configurations. A custom genetic algorithm (GA) was created to “wrap” the

  4. Excited states of ReO4-: A comprehensive time-dependent relativistic density functional theory study

    Science.gov (United States)

    Xu, Wenhua; Ma, Jianyi; Peng, Daoling; Zou, Wenli; Liu, Wenjian; Staemmler, Volker

    2009-02-01

    The perrhenate anion, ReO4-, is taken as a showcase of heavy transition metal complexes, to examine the performance of time-dependent relativistic density functional linear response theory for electronic excitations, which is based on a newly proposed exact two-component Hamiltonian resulting from the symmetrized elimination of the small component. In total 30 scalar and 63 spinor excited states are investigated and the results are grossly in good agreement with those by the singles and doubles coupled-cluster linear response theory. It is found that only a few scalar states of 3T1 and 3T2 symmetries are split significantly by the spin-orbit coupling, whereas only those excited states involving the Rydberg-type virtual orbital are affected by the solvent effects. The nature of the optical absorption spectra is also highlighted.

  5. Excited states of ReO4-: A comprehensive time-dependent relativistic density functional theory study

    International Nuclear Information System (INIS)

    Xu Wenhua; Ma Jianyi; Peng Daoling; Zou Wenli; Liu Wenjian; Staemmler, Volker

    2009-01-01

    The perrhenate anion, ReO 4 - , is taken as a showcase of heavy transition metal complexes, to examine the performance of time-dependent relativistic density functional linear response theory for electronic excitations, which is based on a newly proposed exact two-component Hamiltonian resulting from the symmetrized elimination of the small component. In total 30 scalar and 63 spinor excited states are investigated and the results are grossly in good agreement with those by the singles and doubles coupled-cluster linear response theory. It is found that only a few scalar states of 3 T 1 and 3 T 2 symmetries are split significantly by the spin-orbit coupling, whereas only those excited states involving the Rydberg-type virtual orbital are affected by the solvent effects. The nature of the optical absorption spectra is also highlighted

  6. Medición de contaminación mediante UAV (Vehículo Aéreo no Tripulado

    Directory of Open Access Journals (Sweden)

    Edwin José Vera-Rozo

    2016-09-01

    Full Text Available Este artículo presenta un procedimiento experimental cuyo objetivo es obtener la medición de contaminación en un relleno sanitario (basurero mediante un Vehículo Aéreo no Tripulado (UAV; La metodología utilizada consistió en realizar un procedimiento detallado para la instrumentación de UAV, el cual fue equipamiento con un sistema para la captura y almacenamiento de datos referente a las variables medidas en tiempo real, el cual posteriormente se puso en vuelo y luego se realizo el procesamiento de la información offline; para finalizar se presentan los resultados obtenidos y conclusiones.

  7. Identificación y control de un Vehículo Aéreo no Tripulado tipo Quadcopter

    Directory of Open Access Journals (Sweden)

    Eduardo Giraldo Suarez

    2017-02-01

    Full Text Available En este artículo se describe el modelo dinámico de un vehículo aéreo no tripulado tipo QuadCopter, se linealiza alrededor de un punto de operación y se aplica un controlador por realimentación de estados que logra llevar el sistema a un estado estable en 100ms. Se aplica un algoritmo de identificación MIMO por mínimos cuadrados al modelo no linealizado obteniendo un error medio cuadrático de 0.2562 grados en una simulación de 50s; se aplica un controlador LQR que logra controlar e identificar el sistema inicial en un tiempo de 3.7s y se compara con un controlador PID convencional obteniendo como resultado un menor tiempo de establecimiento y mejor seguimiento de referencia en el controlador LQR.

  8. Temporal evolution of mineralization events in the Bohemian Massif inferred from the Re-Os geochronology of molybdenite

    Science.gov (United States)

    Ackerman, Lukáš; Haluzová, Eva; Creaser, Robert A.; Pašava, Jan; Veselovský, František; Breiter, Karel; Erban, Vojtěch; Drábek, Milan

    2017-06-01

    Molybdenite is a common mineral accompanying Sn-W, Au, and base metal mineralizations located in different geotectonic units of the Bohemian Massif, but it is also widespread in granitoids and/or related quartz veins/pegmatites forming disseminated Mo mineralization. Thirty Re-Os ages were obtained for molybdenite samples from the Bohemian Massif to provide constraints on the timing and duration of mineralization event(s) within the framework of previously published geochronological data for the host and/or associated rocks. The obtained data for Sn-W-(Li) deposits in the Erzgebirge metallogenetic province indicate the predominance of one and/or multiple short-time mineralization events taking place between ˜319 and 323 Ma, with the exception of the Krupka deposit associated with the Altenberg-Teplice caldera where the data may suggest prolonged activity until ˜315 Ma. The ages of the Pb-Zn-(Au-Mo) Hůrky u Rakovníka and Fe-Cu-As Obří důl mineralizations from the exocontacts of the Čistá pluton and Krkonoše-Jizera Plutonic Complex, respectively, provide evidence for synchronous emplacement of the ore and the associated granitic rocks. In contrast, the Padrť Fe-As-Mo mineralization postdates the age of the associated Padrť granite. Disseminated Mo mineralization in Cadomian and Variscan granitoids and/or related to quartz veins/pegmatites provides Re-Os ages that overlap with the previously published geochronological data for the host rocks, suggesting coeval evolution. Molybdenite samples from the Sázava suite granites of the Central Bohemian Plutonic Complex (CBPC) have resolvable younger ages than their host granites, but similar to the age of spatially related Au mineralization which is associated with the latest evolution of the CBPC.

  9. AsTeRICS.

    Science.gov (United States)

    Drajsajtl, Tomáš; Struk, Petr; Bednárová, Alice

    2013-01-01

    AsTeRICS - "The Assistive Technology Rapid Integration & Construction Set" is a construction set for assistive technologies which can be adapted to the motor abilities of end-users. AsTeRICS allows access to different devices such as PCs, cell phones and smart home devices, with all of them integrated in a platform adapted as much as possible to each user. People with motor disabilities in the upper limbs, with no cognitive impairment, no perceptual limitations (neither visual nor auditory) and with basic skills in using technologies such as PCs, cell phones, electronic agendas, etc. have available a flexible and adaptable technology which enables them to access the Human-Machine-Interfaces (HMI) on the standard desktop and beyond. AsTeRICS provides graphical model design tools, a middleware and hardware support for the creation of tailored AT-solutions involving bioelectric signal acquisition, Brain-/Neural Computer Interfaces, Computer-Vision techniques and standardized actuator and device controls and allows combining several off-the-shelf AT-devices in every desired combination. Novel, end-user ready solutions can be created and adapted via a graphical editor without additional programming efforts. The AsTeRICS open-source framework provides resources for utilization and extension of the system to developers and researches. AsTeRICS was developed by the AsTeRICS project and was partially funded by EC.

  10. Preservation of an Archaean whole rock Re-Os isochron for the Venetia lithospheric mantle: Evidence for rapid crustal recycling and lithosphere stabilisation at 3.3 Ga

    Science.gov (United States)

    van der Meer, Quinten H. A.; Klaver, Martijn; Reisberg, Laurie; Riches, Amy J. V.; Davies, Gareth R.

    2017-11-01

    Re-Os and platinum group element analyses are reported for peridotite xenoliths from the 533 Ma Venetia kimberlite cluster situated in the Limpopo Mobile Belt, the Neoarchaean collision zone between the Kaapvaal and Zimbabwe Cratons. The Venetian xenoliths provide a rare opportunity to examine the state of the cratonic lithosphere prior to major regional metasomatic disturbance of Re-Os systematics throughout the Phanerozoic. The 32 studied xenoliths record Si-enrichment that is characteristic of the Kaapvaal lithospheric mantle and can be subdivided into five groups based on Re-Os analyses. The most pristine group I samples (n = 13) display an approximately isochronous relationship and fall on a 3.28 ± 0.17 Ga (95 % conf. int.) reference line that is based on their mean TMA age. This age overlaps with the formation age of the Limpopo crust at 3.35-3.28 Ga. The group I samples derive from ∼50 to ∼170 km depth, suggesting coeval melt depletion of the majority of the Venetia lithospheric mantle column. Group II and III samples have elevated Re/Os due to Re addition during kimberlite magmatism. Group II has otherwise undergone a similar evolution as the group I samples with overlapping 187Os/188Os at eruption age: 187Os/188OsEA, while group III samples have low Os concentrations, unradiogenic 187Os/188OsEA and were effectively Re-free prior to kimberlite magmatism. The other sample groups (IV and V) have disturbed Re-Os systematics and provide no reliable age information. A strong positive correlation is recorded between Os and Re concentrations for group I samples, which is extended to groups II and III after correction for kimberlite addition. This positive correlation precludes a single stage melt depletion history and indicates coupled remobilisation of Re and Os. The combination of Re-Os mobility, preservation of the isochronous relationship, correlation of 187Os/188Os with degree of melt depletion and lack of radiogenic Os addition puts tight constraints on

  11. Processamento de imagens de veículos aéreos não tripulados para estudos da vegetação

    OpenAIRE

    Luna Avilés, Inti Ernesto

    2012-01-01

    O objetivo principal desta tese de mestrado foi avaliar as aplicações ambientais e agrícolas de imagens obtidas com veículos aéreos não-tripulados (VANT) para estudar a vegetação e para avaliar o processamento de imagens envolvido, a fim de obter informação útel e compatível com outro tipo de geo-dados. Imagens dos veículos aéreos não tripulados foram processadas em três diferentes casos de estudo individualmente descritos e analisados com uma estreita relação entre si. (1) ...

  12. Palynology, geochemistry and Re-Os age of the Lower-Middle Pennsylvanian stage boundary, central Appalachian basin, USA

    Science.gov (United States)

    Geboy, N.; Tripathy, G. R.; Ruppert, L. F.; Eble, C. F.; Blake, B. M.; Hannah, J. L.; Stein, H. J.

    2014-12-01

    The central Appalachian basin (CAB) in the eastern United States contains complicated sedimentary sequences often with thin and discontinuous strata. As an economically important coal-producing region, the basin's architectural framework and depositional history are important to understand. Typically, eustatic marine incursions, marked with black shale deposits, are used for basin-wide correlation. The Betsie Shale Member of the Kanawha Formation represents one of these relatively thick and laterally extensive marine zones. This study examines the palynoflora of the Matewan coalbed, which conformably underlies the Betsie, in the context of a new Re-Os date for the Betsie Shale Member and additional geochemical measures. At its base, the Matewan contains abundant lycopsid tree spores, indicative of a submerged, flooded paleomire. Upsection, biodiversity increases to include small fern and calamite spores as well as cordaite pollen. Combined with an observed increase of inertinite, the diversification of palynoflora suggests surficial peat exposure and drying out of the paleomire. A S-rich (28 wt. %) shaley parting separates these lower and upper benches of the Matewan and may represent an initial marine pulse prior to the glacioeustatic incursion that ultimately flooded the Matewan and deposited the overlying Betsie Shale. The Betsie is organic-rich (3.05 - 4.89 wt. % TOC) with Re and Os content ranging from 320 - 1,200 ppb and 1.5 - 5.3 ppb, respectively. The highly enriched Re values result in notably high parent:daughter ratios (187Re/188Os = 3,644 - 5,737). The Re-Os isotopic data yield a Model 1 age of 323 ± 7.8 Ma (n = 7; MSWD = 0.63) with evidence that the true age lies closer to the younger end of the uncertainty. This age is consistent with previous paleontologic-based interpretations but represents the first directly measured radiometric date for the Betsie. An absolute age for the Betsie is a critical result, as the member is correlated with units in

  13. Valor nutricional de seis plantas arbóreo-arbustivas consumidas por cabras en la Mixteca Poblana, México

    Directory of Open Access Journals (Sweden)

    Jorge Hernández Hernández

    2015-09-01

    Full Text Available En las comunidades de Maninalcingo y Tehuaxtla ubicadas en la región Mixteca, Puebla, México, se evaluó la composición nutricional de seis plantas arbóreo-arbustivas consumidas por el ganado caprino (Palo de Brasil, Tehuistle, Barba de chivo, Huamúchil, Tlaxistle negro y Cubata, en época lluviosa. Se analizaron tres unidades de producción familiar, donde se colectaron hojas, flores y frutos (vainas. Para comparar el promedio de bocados/h y la parte de la planta consumida por los caprinos se aplicó la prueba de Tukey y, estadística descriptiva para determinar la dispersión entre los componentes bromatológicos de las partes de la planta de la población total de arbóreo-arbustivas evaluadas. Las muestras estuvieron constituidas por 200 g de peso verde (luego deshidratada. La materia orgánica (MO, ceniza (Ce y proteína bruta (PB se obtuvieron por medio de la técnica AOAC (1997. Para el caso de la fibra detergente neutra (DDN, fibra detergente ácida (FDA y lignina (Lig por medio del método Van Soest.  Los resultados demuestran que el Huamúchil (Pithecellobium dulce mezclado con hoja y vaina mostró mejor media de PB (18.3% ±1.08, la mejor PB fue para la fracción hoja (14.4%±0.42 de Tehuistle (Acacia bilimekii var. Robusta Miranda y 94.4%±1.02 en MO. El Huamúchil mezclado con hoja y vaina tuvo el promedio más alto de Ce (12.3±0.88, mientras que la mezcla de vaina y cáscara de Cubata alcanzaron 52.7%±1.8 y 49.8%±1.04 de FDN y FDA, respectivamente. En el caso de lignina, la hoja de Tehuistle alcanzó 18.4%±0.98.

  14. Impacto de la red de alta velocidad española en el tráfico aéreo

    OpenAIRE

    Portillo Vallet, Pablo

    2009-01-01

    El objetivo de este trabajo es el análisis del impacto de la red de Alta Velocidad Española (AVE) sobre el tráfico aéreo peninsular en el horizonte del año 2020. La definición de las futuras líneas de Alta Velocidad se ha obtenido del Plan Estratégico de Infraestructuras y Transportes (PEIT) propuesto por el Ministerio de Fomento.

  15. Partos cesáreos no Piauí: tendência e fatores associados no período 2000-2011

    Directory of Open Access Journals (Sweden)

    Alberto Madeiro

    Full Text Available Resumo OBJETIVO: analisar a tendência da proporção de partos cesáreos e fatores associados no Piauí, Brasil, de 2000 a 2011. MÉTODOS: estudo de série temporal e transversal, com dados dos partos hospitalares de primíparas registrados no Sistema de Informações sobre Nascidos Vivos (Sinasc. RESULTADOS: a proporção de partos cesáreos aumentou de 34,4% em 2000 para 52,1% em 2011 (variação percentual anual +4,4; IC95% 3,6;5,1; mulheres brancas (RP=1,72; IC95% 1,63;1,86, com 40 anos ou mais de idade (RP=2,17; IC95% 2,09;2,28, com 12 anos ou mais de estudo (RP=1,86; IC95% 1,77;1,96, que realizaram sete ou mais consultas de pré-natal (RP=2,08; IC95% 1,97;2,18, residentes em municípios com mais de 300 mil habitantes (RP=1,68; IC95% 1,62;1,80 e com índice de desenvolvimento humano mais elevado (RP=1,61; IC95% 1,51;1,73 mostraram maiores proporções de partos cesáreos. CONCLUSÃO: a ocorrência de partos cesáreos foi elevada e mais frequente em mulheres de baixo risco obstétrico.

  16. Molybdenite Re-Os dating of Mo-Th-Nb-REE rich marbles: pre-Variscan processes in Moldanubian Variegated Group (Czech Republic

    Directory of Open Access Journals (Sweden)

    Drábek Milan

    2015-06-01

    Full Text Available In an effort to contribute to the discussion concerning the age of rocks of the Moldanubian Variegated Group, we have undertaken Re-Os dating of molybdenite of banded carbonatite-like marbles (CLM from the graphite mine Václav at Bližná (Southern Bohemia, which belong to the metamorphic sequence of this group. The Re-Os model ages for the molybdenites range between 493 and 497 Ma and apparently correspond to the early stages of metamorphism connected with pre-Variscan rift-related tectono-metamorphic events, which affected and recrystallized sedimentary CLM material rich in Mo-Th-Nb-REE. The molybdenite bearing carbonatite like marbles situated in the footwall of Bližná graphite mine have been interpreted as carbonates with a large share of volcano-detritic material derived from contemporaneous primitive alkaline (carbonatite-like volcanism deposited in a shallow marine lagoonal environment. There is no geological evidence for the participation of fluids mobilized from host rocks in the formation of the CLM. Because the Re-Os chronometer in molybdenite is demonstrably stable through later Variscan facies metamorphism, the molybdenite chronometer has not been affected by subsequent thermal overprints associated with the Variscan orogeny.

  17. Studies on electrochemical lithium insertion in isostructural titanium niobate and tantalate phases with shear ReO3 structure

    International Nuclear Information System (INIS)

    Saritha, D.; Varadaraju, U.V.

    2013-01-01

    Graphical abstract: - Highlights: • Electrochemical lithium insertion into ReO 3 type phases TiNb 2 O 7 , TiTa 2 O 7 is feasible. • TiNb 2 O 7 exhibits good cycling behavior and high reversible capacity of 212 mAh g −1 . • TiTa 2 O 7 exhibits reversible capacity of 100 mAh g −1 . - Abstract: TiNb 2 O 7 and TiTa 2 O 7 phases are synthesized by solid-state reaction method and are investigated for electrochemical Li insertion/extraction. The electrochemical insertion of Li in these phases is characterized by both solid solution and two-phase regimes. The structure is stable toward Li insertion/extraction. The first cycle discharge capacity values are 307 mAh g −1 and 215 mAh g −1 in the voltage range of 3.0–1.0 V for TiNb 2 O 7 and TiTa 2 O 7 phases, respectively. The discharge capacities of TiNb 2 O 7 and TiTa 2 O 7 are 212 mAh g −1 and 100 mAh g −1 , respectively, after 20 cycles

  18. Um método para o planejamento do roteamento contingencial de tráfego aéreo

    Directory of Open Access Journals (Sweden)

    Leonardo Guerra de Rezende Guedes

    2008-10-01

    Full Text Available Neste trabalho, considera-se o problema logístico de rotear as aeronaves de uma companhia para que esta possa ao longo do tempo voltar seus vôos aos horários definidos pela Agência Nacional de Aviação Civil - ANAC. Para tal é utilizada a representação em Redes de Petri a qual permite o controle do funcionamento dos vôos da companhia, sendo possível controlar o movimento dos aviões pela rede assim como o tempo do vôo. A construção dos planos necessários ao retorno dos horários da companhia sugere uma busca por seqüências de vôos sobre a Rede de Petri. A técnica a ser utilizada para ser feita esta busca são os Algoritmos Genéticos. Este artigo apresenta a aplicação conjunto de Redes de Petri e Algoritmos Genéticos na resolução do problema de roteamento contingencial de tráfego aéreo objetivando ao restauração das rotas e horários de vôos padrões.

  19. Similaridade entre Adultos e Regenerantes do Componente Arbóreo em Floresta com Araucária

    Directory of Open Access Journals (Sweden)

    Manoela Drews de Aguiar

    2017-08-01

    Full Text Available RESUMO O estudo objetivou inventariar o componente arbóreo regenerante em uma floresta no Planalto Sul de Santa Catarina e compará-lo ao componente adulto da mesma área. Foram alocadas 25 parcelas, onde os regenerantes e adultos foram identificados e quantificados. Foi calculado o Índice de Regeneração Natural Total (RNT de cada espécie. Para verificar a similaridade entre os componentes, foi utilizada a Análise de Similaridade e o índice de Jaccard. Foram amostrados 503 regenerantes, pertencentes a 58 espécies e 29 famílias. Myrtaceae foi a família de maior riqueza (13. Leandra regnelli (Triana Cogn., Myrcia splendens (Sw. DC. e Miconia cinerascens Miq. apresentaram os maiores valores de RNT. Houve elevada dissimilaridade entre regenerantes e adultos, sendo que 37,5% das espécies do componente adulto não tiveram representantes na regeneração natural. Conclui-se que existe uma baixa capacidade regenerativa da maior parte das espécies, o que pode estar associado à presença de gado na área.

  20. Ga-Bi-Te system

    International Nuclear Information System (INIS)

    Rustamov, P.G.; Seidova, N.A.; Shakhbazov, M.G.; AN Azerbajdzhanskoj SSR, Baku. Inst. Neorganicheskoj i Fizicheskoj Khimii)

    1976-01-01

    To elucidate the nature of interaction in the system Ga-Bi-Te, a study has been made of sections GaTe-Bi 2 Te 3 , Ga 2 Te 3 -Bi, GaTe-Bi and Bi 2 Te 3 -Ga. The alloys have been prepared by direct melting of the components or their alloys with subsequent homogenizin.o annealing at 400 deg C. The study has been made by the methods of differential thermal, microstructural analysis and by microhardness measurements. On the basis of literature data and data obtained a projection of the liquidus surface of the phase diagram for the system Ga-Bi-Te has been constructed. In the ternary system there are 17 curves of monovariant equilibrium dividing the liquidus into 10 fields of primary crystallization of phases, 9 points of non-variant equilibrium of which 4 points are triple eutectics and 5 points are triple peritectics

  1. Fluid inclusion characteristics and molybdenite Re-Os geochronology of the Qulong porphyry copper-molybdenum deposit, Tibet

    Science.gov (United States)

    Li, Yang; Selby, David; Feely, Martin; Costanzo, Alessandra; Li, Xian-Hua

    2017-02-01

    The Qulong porphyry copper and molybdenum deposit is located at the southwest margin of the Lhasa Terrane and in the eastern region of the Gangdese magmatic belt. It represents China's largest porphyry copper system, with ˜2200 million tonnes of ore comprising 0.5 % Cu and 0.03 % Mo. The mineralization is associated with Miocene granodiorite, monzogranite and quartz-diorite units, which intruded into Jurassic volcanic units in a post-collisional (Indian-Asian) tectonic setting. Field observations and core logging demonstrate the alteration and mineralization at Qulong are akin to typical porphyry copper systems in subduction settings, which comprise similar magmatic-hydrothermal, potassic, propylitic and phyllic alteration assemblages. Molybdenite Re-Os geochronology confirms the relative timeframe defined by field observations and core logging and indicates that the bulk copper and molybdenum at Qulong were deposited within 350,000 years: between 16.10 ± 0.06 [0.08] (without and with decay constant uncertainty) and 15.88 ± 0.06 [0.08] Ma. This duration for mineralization is in direct contrast to a long-lived intrusive episode associated with mineralization based on previous zircon U-Pb data. Our fluid inclusion study indicates that the ore-forming fluid was oxidized and contained Na, K, Ca, Fe, Cu, Mo, Cl and S. The magmatic-hydrothermal transition occurred at ˜425 °C under lithostatic pressure, while potassic, propylitic and phyllic alteration occurred at hydrostatic pressure with temperature progressively decreasing from 425 to 280 °C. The fluid inclusion data presented here suggests that there has been ˜2.3 km of erosion at Qulong after its formation, and this erosion may be related to regional uplift of the Lhasa Terrane.

  2. Growth And Characterization Of LPE CdHgTe/CdZnTe/CdZnTe Structure

    Science.gov (United States)

    Pelliciari, B.; Chamonal, J. P.; Destefanis, G. L.; Dicioccio, L.

    1988-05-01

    The liquid phase epitaxial technique is used to grow Hgl_x Cdx Te (x = .23) from a Te - rich solution onto a Cdl_y ZnyTe (y = .04) buffer layer grown from a Te-rich solution onto a Cdi_yZnyTe bulk substrate in an open tube multibin horizontal slider apparatus.Growth conditions and physical characterizations of both the buffer layer and the CdHgTe layer are given ; electrical properties of the CdHgTe layer are also presen-ted. PV detectors were successfully obtained on such a structure using an ion-implanted technology and their characteristics at 77 K for a 10.1 ,um cut-off wavelength are given.

  3. Behavior of Re and Os during contact between an aqueous solution and oil: Consequences for the application of the Re-Os geochronometer to petroleum

    Science.gov (United States)

    Mahdaoui, Fatima; Michels, Raymond; Reisberg, Laurie; Pujol, Magali; Poirier, Yannick

    2015-06-01

    Several recent studies have raised the exciting possibility that oils can be dated using the Re-Os radioisotope system. However the exact nature of the events dated by this technique often remains unclear. Geochronologic interpretation of Re-Os data for oils is hampered by our limited knowledge of how these metals behave in petroleum systems. In particular, it is difficult to understand how isotopic homogenization, an essential prerequisite for the development of an isochronal relationship, can be achieved at the scale of a petroleum basin. The mechanisms capable of fractionating the Re/Os ratio in a suite of oils are also poorly understood. For this reason, we have performed an experimental study aimed at investigating the behavior of Re and Os during a particularly widespread phenomenon in petroleum systems, the interaction of formation waters with oils during migration. Contact experiments between natural oils and aqueous solutions enriched in Re and/or Os were carried out for varying lengths of time (6 h to 5 months), at different temperatures (25-150 °C), over a wide range of metal concentrations in the enriched solution (0.001-100 μg/g for Re; 1 and 10 ng/g for Os). In addition, the effect of oil composition on Re-Os exchange at the water-oil interface was examined by testing two oils with very different properties. All of our results demonstrate that Re and Os are transferred massively and very rapidly from the aqueous solution to the organic phase. This is true regardless of temperature or oil composition. It is also true for a very wide range of metal concentrations in the aqueous solution, up to an apparent saturation level that exceeds natural concentrations in oils by several orders of magnitude. Given the efficiency of Re and Os transfer from water to oil demonstrated here, and assuming that our findings are applicable to natural conditions, water/oil ratios of only about 250 would be needed to explain the Re and Os contents of most oils, based on

  4. Binding of ReO4- with an engineered MoO42--binding protein: towards a new approach in radiopharmaceutical applications

    International Nuclear Information System (INIS)

    Aryal, Baikuntha P.; Brugarolas, Pedro; He, Chuan

    2012-01-01

    Radiolabeled biomolecules are routinely used for clinical diagnostics. 99m Tc is the most commonly used radioactive tracer in radiopharmaceuticals. 188 Re and 186 Re are also commonly used as radioactive tracers in medicine. However, currently available methods for radiolabeling are lengthy and involve several steps in bioconjugation processes. In this work we present a strategy to engineer proteins that may selectively recognize the perrhenate (ReO 4 - ) ion as a new way to label proteins. We found that a molybdate (MoO 4 2- )-binding protein (ModA) from Escherichia coli can bind perrhenate with high affinity. Using fluorescence and isothermal titration calorimetry measurements, we determined the dissociation constant of ModA for ReO 4 - to be 541 nM and we solved a crystal structure of ModA with a bound ReO 4 - . On the basis of the structure we created a mutant protein containing a disulfide linkage, which exhibited increased affinity for perrhenate (K d = 104 nM). High-resolution crystal structures of ModA (1.7 (angstrom)) and A11C/R153C mutant (2.0 (angstrom)) were solved with bound perrhenate. Both structures show that a perrhenate ion occupies the molybdate binding site using the same amino acid residues that are involved in molybdate binding. The overall structure of the perrhenate-bound ModA is unchanged compared with that of the molybdate-bound form. In the mutant protein, the bound perrhenate is further stabilized by the engineered disulfide bond.

  5. Binding of ReO4(-) with an engineered MoO4(2-)-binding protein: towards a new approach in radiopharmaceutical applications.

    Science.gov (United States)

    Aryal, Baikuntha P; Brugarolas, Pedro; He, Chuan

    2012-01-01

    Radiolabeled biomolecules are routinely used for clinical diagnostics. (99m)Tc is the most commonly used radioactive tracer in radiopharmaceuticals. (188)Re and (186)Re are also commonly used as radioactive tracers in medicine. However, currently available methods for radiolabeling are lengthy and involve several steps in bioconjugation processes. In this work we present a strategy to engineer proteins that may selectively recognize the perrhenate (ReO(4)(-)) ion as a new way to label proteins. We found that a molybdate (MoO(4)(2-))-binding protein (ModA) from Escherichia coli can bind perrhenate with high affinity. Using fluorescence and isothermal titration calorimetry measurements, we determined the dissociation constant of ModA for ReO(4)(-) to be 541 nM and we solved a crystal structure of ModA with a bound ReO(4)(-). On the basis of the structure we created a mutant protein containing a disulfide linkage, which exhibited increased affinity for perrhenate (K(d) = 104 nM). High-resolution crystal structures of ModA (1.7 Å) and A11C/R153C mutant (2.0 Å) were solved with bound perrhenate. Both structures show that a perrhenate ion occupies the molybdate binding site using the same amino acid residues that are involved in molybdate binding. The overall structure of the perrhenate-bound ModA is unchanged compared with that of the molybdate-bound form. In the mutant protein, the bound perrhenate is further stabilized by the engineered disulfide bond. © SBIC 2011

  6. Permanencia en vivero del acodo aéreo de Myrciaria dubia “camu camu” y su efecto en la supervivencia en campo definitivo

    Directory of Open Access Journals (Sweden)

    Jorge Gálvez

    2013-06-01

    Full Text Available El camu camu, es una especie frutal nativa, silvestre y cultivada de la región amazónica, importante el alto contenido de vitamina C, antocianinas y compuestos fenólicos presentes en la pulpa y cáscara de sus frutos. Se propaga en forma convencional por semilla botánica, con la desventaja de producir plantaciones desuniformes producto de la alogamia que presenta la planta; sin embargo la propagación vegetativa se presenta como una alternativa que permite mantener el genotipo intacto y asegura el aprovechamiento del germoplasma valioso. El objetivo del trabajo, fue evaluar el tiempo de permanencia del acodo aéreo de camu camu en vivero, para obtener mayores porcentajes de supervivencia en campo definitivo. El experimento se ejecutó en el Campo Experimental “San Miguel” de la Estación Experimental Agraria San Roque del INIA. Los acodos aéreos fueron realizados en una plantación comercial del INIA, luego de enraizados, se separaron y se trasladaron a campo definitivo o a vivero de acuerdo con los tratamientos en estudio. El diseño utilizado fue de bloques completos al azar con tres repeticiones y cuatro niveles del factor tiempo (0, 1, 2 y 3 meses. La variable principal estudiada fue la supervivencia de los acodos trasplantados. El mejor tratamiento fue cuando el acodo aéreo permaneció 3 meses en vivero con 98,61% de supervivencia, a los 7 meses después del trasplante.

  7. Permanencia en vivero del acodo aéreo de Myrciaria dubia “camu camu” y su efecto en la supervivencia en campo definitivo

    Directory of Open Access Journals (Sweden)

    Jorge Gálvez

    2013-06-01

    Full Text Available El camu camu, es una especie frutal nativa, silvestre y cultivada de la región amazónica, importante el alto contenido de vitamina C, antocianinas y compuestos fenólicos presentes en la pulpa y cáscara de sus frutos. Se propaga en forma convencional por semilla botánica, con la desventaja de producir plantaciones desuniformes producto de la alogamia que presenta la planta; sin embargo, la propagación vegetativa se presenta como una alternativa que permite mantener el genotipo intacto y asegura el aprovechamiento del germoplasma valioso. El objetivo del trabajo, fue evaluar el tiempo de permanencia del acodo aéreo de camu camu en vivero, para obtener mayores porcentajes de supervivencia en campo definitivo. El experimento se ejecutó en el Campo Experimental “San Miguel” de la Estación Experimental Agraria San Roque del INIA. Los acodos aéreos fueron realizados en una plantación comercial del INIA, luego de enraizados, se separaron y se trasladaron a campo definitivo o a vivero de acuerdo con los tratamientos en estudio. El diseño utilizado fue de bloques completos al azar con tres repeticiones y cuatro niveles del factor tiempo (0, 1, 2 y 3 meses. La variable principal estudiada fue la supervivencia de los acodos trasplantados. El mejor tratamiento fue cuando el acodo aéreo permaneció 3 meses en vivero con 98,61% de supervivencia, a los 7 meses después del trasplante.

  8. Reingeniería del proceso de logística de la empresa de transporte aéreo de pasajeros y carga Saereo

    OpenAIRE

    Benavides Ramos, Ximena Alejandra

    2015-01-01

    La presente tesis consiste en realizar una reingeniería del proceso de logística de una empresa de servicios aéreos ejecutivos, este proyecto pretende optimizar la importación y exportación de repuestos aeronáuticos, utilizando menos tiempos y recursos operativos que permitan incrementar el desempeño para mantener aeronavegable la aeronave. La metodología para el estudio de los procesos convenientes para el tipo de operación que la empresa Saereo desarrolla fueron, en primer té...

  9. Ensayo de aislamiento acústico a ruido aéreo de los cerramientos exteriores y particiones realizados con paneles de madera

    Directory of Open Access Journals (Sweden)

    Pacios Álvarez, Antonia

    2007-06-01

    Full Text Available The house prototype of the Provisional Emergency House System uses wood and its derivatives for the facades, floor structure, roofing and partitions.  The extensive use of wooden panels for the construction and the lack of data, in Spain, about their acoustic behavior bring up the necessity to make in situ measurements of the acoustic isolation to airborne sound. Panels used for facades and partitions are built with a wooden framework and membrane of oriented strand board in both sides, for the facades, and of laminated plaster boards for the inner partitions. With the objective of verifying the sound insulation of the facades according to Spanish Standard UNE EN ISO 140-5, in situ measurements of airborne sound insulation of facade elements and facades have been made; according to Spanish Standard UNE EN ISO 140-4, in situ measurements of airborne sound insulation between rooms for internal walls have also been made. The procedure of the global insulation has been followed to measure the acoustic insulation of complete facades without making distinction between the elements that form it.El prototipo de vivienda del Sistema de Vivienda Provisional de Emergencia utiliza principalmente la madera y sus derivados tanto en los cerramientos y particiones como en el forjado y la cubierta. El empleo de soluciones constructivas ligeras y la falta de datos en España acerca del comportamiento acústico de los mismos plantea la necesidad de realizar mediciones in situ del aislamiento acústico a ruido aéreo. El panel base de cerramiento y particiones se construye partiendo de un entramado de montantes de madera con membrana en ambas caras de tableros de virutas de madera orientadas, para el caso de los cerramientos exteriores, y de tableros laminados de yeso para las particiones interiores. Con el objeto de comprobar el aislamiento acústico de dichos cerramiento se han realizado ensayos siguiendo la Norma UNE EN ISO 140-5 para la medición in situ del

  10. Implementação de modelo para balanceamento de fluxos aplicado ao gerenciamento de tráfego aéreo

    Directory of Open Access Journals (Sweden)

    Bueno Borges de Souza

    2009-10-01

    Full Text Available

    Este trabalho descreve um sistema de auxílio à decisão com metodologias de Teoria dos Grafos e Inteligência Artificial para dar suporte ao Gerenciamento de Fluxo de Tráfego Aéreo Brasileiro. Trata-se de um modelo de gerenciamento de fluxo baseado em grafos com adaptações heurísticas para a regulação dinâmica do fluxo. O modelo fundamenta a arquitetura do Módulo de Balanceamento de Fluxo (MBF integrante do Sistema Distribuído de Apoio a Decisão aplicado ao Gerenciamento Tático do Fluxo de Tráfego(SISCONFLUX, em desenvolvimento, e tem o objetivo de melhorar o gerenciamento do espaço aéreo nacional. O MBF foi proposto para dar suporte ao sistema em operação no Primeiro Centro Integrado de Defesa Aérea e Controle de Tráfego Aéreo (CINDACTA I, fornecendo informações adicionais para o processo aplicado pelos controladores a fim de amenizar a carga de trabalho e melhorar os resultados de suas ações. Usando técnicas de maximização de fluxo adaptados da Teoria dos Grafos, o MBF foi desenvolvido como um modelo de análise que determina o tempo de separação entre decolagens a partir das terminais integrantes da Região de Informação de Vôo de Brasília (FIR-BS e distribui a folga do fluxo ao longo do espaço aéreo controlado, objetivando prevenir ou reduzir o congestionamento nos diversos setores da FIR-BS. O MBF dá suporte à regulação do fluxo de tráfego auxiliando os controladores e as outras unidades dentro do SISCONFLUX.

  11. Re-Os Geochronology Pins Age and Os Isotope Composition of Middle Triassic Black Shales and Seawater, Barents Sea and Spitsbergen (Svalbard)

    Science.gov (United States)

    Xu, G.; Hannah, J. L.; Bingen, B.; Stein, H. J.; Yang, G.; Zimmerman, A.; Weitschat, W.; Weiss, H. M.

    2008-12-01

    Absolute age control throughout the Triassic is extraordinarily sparse. Two "golden spikes" have been added recently (http://www.stratigraphy.org/cheu.pdf) within the otherwise unconstrained Triassic, but ages of stage boundaries remain controversial. Here we report two Re-Os isochrons for Anisian (Middle Triassic) black shales from outcrop in western Svalbard and drill core from the Svalis Dome about 600 km to the SE in the Barents Sea. Black shales of the Blanknuten Member, Botneheia Formation, from the type section at Botneheia, western Spitsbergen (Svalbard), have total organic carbon (TOC) contents of 2.6 to 6.0 wt%. Rock-Eval data suggest moderately mature (Tmax = 440-450° C) Type II-III kerogens (Hydrogen Index (HI) = 232-311 mg HC/g TOC). Re-Os data yield a well-constrained Model 3 age of 241 Ma and initial 187Os/188Os (Osi) of 0.83 (MSWD = 16, n = 6). Samples of the possibly correlative Steinkobbe Formation from IKU core hole 7323/07-U-04 into the Svalis Dome in the Barents Sea (at about 73°30'N, 23°15'E) have TOC contents of 1.4 to 2.4%. Rock-Eval data suggest immature (Tmax = 410-430°) Type II-III kerogens (HI = 246-294 mg HC/g TOC). Re-Os data yield a precise Model 1 age of 239 Ma and Osi of 0.776 (MSWD = 0.2, n = 5). The sampled section of Blanknuten shale underlies a distinctive Frechitas (formerly Ptychites) layer, and is therefore assumed to be middle Anisian. The Steinkobbe core was sampled at 99-100 m, just above the Olenekian-Anisian transition. It is therefore assumed to be lower Anisian. The two isochron ages overlap within uncertainty, and fall within constraints provided by biozones and the current ICS-approved stage boundary ages. The Re-Os ages support the correlation of the Botneheia and Steinkobbe formations. The nearly identical Osi ratios suggest regional homogeneity of seawater and provide new information for the Os seawater curve, marking a relatively high 187Os/188Os ratio during profound ocean anoxia in the Middle Triassic.

  12. EL HÁNDICAP DEL TRANSPORTE AÉREO PARA EL DESARROLLO INICIAL DEL TURISMO DE MASAS EN LAS ISLAS CANARIAS

    Directory of Open Access Journals (Sweden)

    José Ángel Hernández Luis

    2011-01-01

    Full Text Available El transporte aéreo, más aún en un territorio fragmentado y alejado como es el caso del Archipiélago canario, ha jugado un papel trascendental para el desarrollo del turismo de masas en los años sesenta y setenta. En efecto, sin la llegada del motor a reacción a Canarias, no se podría comprender el espectacular desarrollo turístico que las Islas experimentaron en este periodo, siendo el principal objetivo de este trabajo, abordar -aunque de forma sucinta-, este proceso absolutamente decisivo para las Islas.

  13. Re-Os and Lu-Hf isotopic constraints on the formation and age of mantle pyroxenites from the Bohemian Massif

    Czech Academy of Sciences Publication Activity Database

    Ackerman, Lukáš; Bizimis, M.; Haluzová, Eva; Sláma, Jiří; Svojtka, Martin; Hirajima, T.; Erban, V.

    256/257, July (2016), s. 197-210 ISSN 0024-4937 Grant - others:Rada Programu interní podpory projektů mezinárodní spolupráce AV ČR(CZ) M100131203 Program:Program interní podpory projektů mezinárodní spolupráce AV ČR Institutional support: RVO:67985831 Keywords : Bohemian Massif * Lu-Hf * mantle * pyroxenite * Re-Os Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.677, year: 2016

  14. Selenium Se and tellurium Te

    International Nuclear Information System (INIS)

    Busev, A.I.; Tiptsova, V.G.; Ivanov, V.M.

    1978-01-01

    The basic methods for determining selenium and tellurium in various objects are presented. The bichromatometric determination of Te in cadmium, zinc and mercury tellurides is based on oxidation of Te(4) to (6) in H 2 SO 4 with potassium bichromate. In steels, Te is determined photometrically with the aid of KI. The determination is hindered by Fe(3), Cu(2), Bi(3) and Se(4) ions, which must be separated. The extraction-photometric determination of Te in native sulfur is carried out with the aid of 5-mercapto-3-(naphthyl-2)-1,3,4-thiadiazolthione-2 (pH=4.8-5.0). The dyed complex is readily extracted with chloroform and benzene. The spectrophotometric determination of Te in selenium is performed with the aid of 3,5-diphenylpyrazoline-1-dithiocarbamate of sodium. Te is determined in commercial indium, arsenic and their semiconductor compounds photometrically with the aid of copper diethyldithiocarbamate. The method permits determining 5x10 -5 % Te in a weighed amount of 0.5 g. The chloride complex of Te(4) with diantipyriodolpropylmethane is quantitatively extracted with dichloroethane from hydrochloric acid solutions. Thus, any amounts of Te can be separated from Se and determined photometrically. The extraction-photometric determination of Te in commercial lead and bismuth is carried out with the aid of pyrazolone derivatives, in commercial copper with the aid of diantipyridolpropylmethane, and in ores (more than 0.01% Te) with the aid of bismuthol 2. Also described is the extraction-polarographic determination of Te in sulfide ores

  15. Kia Tangi Te Titi--Permission to Speak

    Science.gov (United States)

    Whitinui, Paul

    2011-01-01

    This book explores what constitutes successful schooling for Maori students in the 21st century. Editor Paul Whitinui has drawn together academic contributions from diverse fields of matauranga (education), matauranga hinengaro (psychology), whakaako hauora (health), akoranga takakau-a-ora (sport and leisure) and others. The book aims to provide a…

  16. TUMOR VENÉREO TRANSMISIBLE CANINO DE PRESENTACIÓN ATÍPICA. REPORTE DE CASO CLÍNICO

    Directory of Open Access Journals (Sweden)

    R. Crossley

    2017-01-01

    Full Text Available Se describe el caso de un paciente canino macho entero, raza Bóxer, de ocho años de edad y 30 kg de peso vivo, que ingresó a consulta en el hospital Clínico Veterinario de la Universidad Santo Tomás, sede Santiago, por un aumento de volumen en el ojo derecho, signo clínico con un curso de dos meses de evolución que no respondió al tratamiento con prednisona oral (0,7 mg/kg, dos veces al día (BID, ni a dexametasona y tobramicina en ungüento oftálmico (1 gota, tres veces al día, TID. Al examen físico se observó una masa en el tercer párpado que desplazaba el ojo lateralmente, además de una masa que se palpaba en la base lateral del pene. Se realizó una ecografía ocular que indicó la presencia de una masa de aspecto irregular con parénquima heterogéneo y características neoplásicas en la zona medial del globo ocular derecho y una ecografía abdominal que permitió detectar una masa dorsal a la vejiga. Al realizar citología ecoguiada de las masas intraabdominal y ocular, bajo sedación, se constató una inflamación supurativa, necrosis y displasia epitelial en la masa periorbitaria sugerente de neoplasia, la cual no se pudo diagnosticar fehaciente - mente; por su parte, la citología de la masa intraabdominal indicó la presencia de Tumor Venéreo Transmisible (TVT. El tratamiento se inició con vincristina (ocho aplicaciones i.v. de 0,7 mg/m² cada 7 días lográndose remisión parcial. Ante una posible resistencia al efecto de la quimioterapia, se decidió modificar la terapia a doxorrubicina (30 mg/m² la cual tuvo respuesta positiva alcanzando remisión completa con una aplicación única.

  17. Te/C nanocomposites for Li-Te Secondary Batteries

    Science.gov (United States)

    Seo, Jeong-Uk; Seong, Gun-Kyu; Park, Cheol-Min

    2015-01-01

    New battery systems having high energy density are actively being researched in order to satisfy the rapidly developing market for longer-lasting mobile electronics and hybrid electric vehicles. Here, we report a new Li-Te secondary battery system with a redox potential of ~1.7 V (vs. Li+/Li) adapted on a Li metal anode and an advanced Te/C nanocomposite cathode. Using a simple concept of transforming TeO2 into nanocrystalline Te by mechanical reduction, we designed an advanced, mechanically reduced Te/C nanocomposite electrode material with high energy density (initial discharge/charge: 1088/740 mA h cm-3), excellent cyclability (ca. 705 mA h cm-3 over 100 cycles), and fast rate capability (ca. 550 mA h cm-3 at 5C rate). The mechanically reduced Te/C nanocomposite electrodes were found to be suitable for use as either the cathode in Li-Te secondary batteries or a high-potential anode in rechargeable Li-ion batteries. We firmly believe that the mechanically reduced Te/C nanocomposite constitutes a breakthrough for the realization and mass production of excellent energy storage systems.

  18. Aardkastanje, onopvallend en te weinig om te eten

    NARCIS (Netherlands)

    Spruijt, T.

    2010-01-01

    Hij staat vanaf half juni volop in bloei, maar wordt door weinigen gezien. Hoewel een zoektocht op Google anders doet vermoeden, wordt hij niet meer gegeten. De Aardkastanje is daarvoor te onopvallend en te zeldzaam in Nederland. Toch is het een bijzondere schermbloem.

  19. PbTe mechanosynthesis from PbO and Te

    International Nuclear Information System (INIS)

    Rojas-Chavez, Hugo; Diaz-de la Torre, Sebastian; Jaramillo-Vigueras, David; Plascencia, Gabriel

    2009-01-01

    Experimental results concerning the mechanosynthesis (MSY), of PbTe from the PbO-Te powder system, at room temperature an atmospheric conditions are reported. XRD results for samples milled for and after 5.4 ks only show PbTe diffraction peaks; neither Te nor PbO or any other solid phase were detected. Particle size and morphology, was followed by SEM observations. Phase evolution and quantification was monitored by Rietveld refinements of the X-ray diffraction data. It was found that the use of lead oxide as a component of the mechanosynthesis system reduces milling time with respect to the Pb-Te metallic system with mechanical alloying.

  20. The quadrupole interaction of 125Te and 129I in polycrystalline Te and in Te single crystals

    International Nuclear Information System (INIS)

    Langouche, G.; Rossum, M. van; Schmidt, K.P.; Coussement, R.

    1975-01-01

    Single crystals as hosts for Te and I sources were used in a study of Te. The Moessbauer spectra of 125 Te and 129 I in polycrystalline Te at liquid He temperature are given. Also presented are the Moessbauer spectra of 125 Te in a Te single crystal for the gamma ray parallel to the c-axis and perpendicular to the c-axis of the crystal at liquid He temperature. (Z.S.)

  1. Bouwlogistieke innovaties weerbarstig te implementeren

    NARCIS (Netherlands)

    Ludema, M.W.; Vries, A.M.R.

    2015-01-01

    Toelevering van bouwmaterialen aan bouwprojecten is complex en verregaande gesegregeerd. De bouwsector staat voor een kans te innoveren op het vlak van de bouwlogistiek. In het verleden is ervaring opgedaan met ‘best-practices’ die voldoende kansen bieden de noodzakelijk innovatie door te voeren.

  2. CdTe as a passivating layer in CdTe/HgCdTe heterostructures

    International Nuclear Information System (INIS)

    Virt, I. S.; Kurilo, I. V.; Rudyi, I. A.; Sizov, F. F.; Mikhailov, N. N.; Smirnov, R. N.

    2008-01-01

    CdTe/Hg 1-x Cd x Te heterostructures are studied. In the structures, CdTe is used as a passivating layer deposited as a polycrystal or single crystal on a single-crystal Hg 1-x Cd x Te film. The film and a passivating layer were obtained in a single technological process of molecular beam epitaxy. The structure of passivating layers was studied by reflection high-energy electron diffraction, and the effect of the structure of the passivating layer on the properties of the active layer was studied by X-ray diffractometry. Mechanical properties of heterostructures were studied by the microhardness method. Electrical and photoelectrical parameters of the Hg 1-x Cd x Te films are reported.

  3. A lógica financeira e o espaço do transporte aéreo comercial Brasileiro Financial logics and the Brazilian aviation market

    Directory of Open Access Journals (Sweden)

    Martin Mundo Neto

    2011-01-01

    Full Text Available Este estudo focou a dinâmica das forças em um espaço particular: o espaço do transporte aéreo comercial brasileiro. Utilizando-se dos conceitos propostos pela análise institucional das organizações e pela sociologia econômica, foram analisadas as estratégias das empresas que dominam este mercado - a TAM Linhas Aéreas e a GOL Linhas Aéreas - e algumas implicações para a estruturação atual. A partir das informações institucionais das empresas que dominam o mercado do transporte aéreo comercial brasileiro, de órgãos governamentais responsáveis pelo controle das atividades e daquelas veiculadas na imprensa de negócios, o estudo procurou indicar os atores responsáveis pela estruturação das empresas dominantes. As duas empresas operam tanto no espaço industrial original, transporte aéreo, como em mercado de capitais. O modelo de negócio da empresa GOL, notadamente a adesão aos investimentos de private equities, seria um dos fatores determinantes para a nova configuração deste espaço industrial. A TAM, no âmbito financeiro, adota estratégia semelhante à GOL. A recente crise aérea e a crise financeira impactaram fortemente as duas empresas, sobretudo no valor de suas ações.This study focuses on the power dynamic of a particular space: Brazilian Airlines Companies. Applying the concepts of Organizational Theory and Economic Sociology, it was possible to analyze the strategies of TAM and GOL airlines, which are companies that dominate the aviation market. Gathering institutional information from those companies, from government entities which control those companies' activities, and also from the business media, this study focused on indicating the social actors responsible for structuring these dominant companies. Both companies operate in the aviation market , but they also operate in the stock market. GOL business model, particularly the use of private equities tools, can be considered a determinant factor for the

  4. Lymphogranuloma venereum: "a clinical and histopathological chameleon?" Linfogranuloma venéreo: "um camaleão clínico e histopatológico?"

    Directory of Open Access Journals (Sweden)

    Georgi Tchernev

    2010-08-01

    Full Text Available Lymphogranuloma venereum is an infection caused by a variety of the bacterium Chlamydia trachomatis. Both genital and extragenital manifestations of the disease can cause serious differential diagnostic difficulties, indirectly leading to progression and dissemination of the infection. This work describes cases of patients with lymphogranuloma venereum showing atypical clinical and/or histopathological findings. It also focuses on alternative therapeutic approaches, such as surgical excision at stage 1, that may lead to a positive outcome. It is not completely clear whether histopathological findings of lymphogranuloma venereum can reveal progression or changes in the course of the disease over time, as is the case in other diseases. We conclude that both clinical and histopathological observations in a larger number of patients are needed in order to further evaluate the findings presented in this article.Linfogranuloma venéreo é uma infecção causada por um tipo específico da bactéria Chlamydia trachomatis. Manifestações genitais e extragenitais da doença podem causar uma série de dificuldades no diagnóstico diferencial, indiretamente levando a progressão ou disseminação da infecção. Este trabalho apresenta casos de pacientes com linfogranuloma venéreo cujos achados clínicos e/ou histopatológicos são atípicos, além de abordar métodos de terapia alternativos, tais como excisão cirúrgica na fase 1, os quais podem trazer um resultado positivo. Ainda não se sabe se achados histopatológicos do linfogranuloma venéreo podem revelar progressão ou mudanças no curso da doença ao longo do tempo, como ocorre com outras enfermidades. Concluímos que observações clínicas e histopatológicas devem envolver um número maior de pacientes a fim de avaliar os resultados clínicos deste trabalho.

  5. EVOLUCIÓN DEL COMPORTAMIENTO VISCOELÁSTICO DEL ASFALTO INDUCIDA BAJO TERMO-OXIDACIÓN IN SITU EN UN REO-REACTOR

    Directory of Open Access Journals (Sweden)

    XIOMARA VARGAS

    2008-01-01

    Full Text Available En este artículo se presentan los resultados del proceso de termo-oxidación de asfalto realizados por primera vez en un reo-reactor. El comportamiento viscoelástico del asfalto pudo ser representado por una ley de potencia (G'(w - wn, G'' (w - w1. La variación del exponente 'n' reflejó los cambios estructurales del asfalto inducidos por el proceso de termo-oxidación. En el intervalo de frecuencia experimental y a 200 y 250°C, los módulos elástico G' y viscoso G'' mostraron una relación del tipo: G'' (w - wn y G' (w ~ wn, este comportamiento es equivalente a un 'gel-débil' y confirma los cambios estructurales del asfalto inducidos por el envejecimiento termo-oxidativo.

  6. Diseño y Construcción de un Transportador Mecánico de Café Cereza por Cable Aéreo

    Directory of Open Access Journals (Sweden)

    Patiño Valencia Fernando

    1994-09-01

    Full Text Available Debido a que la zona cafetera colombiana es de difícil topografía, el transporte del café desde las plantaciones hasta el beneficiadero se hace complicado y requiere de la utilización de animales de carga, fuerza humana y/o vehículos para trasladar por medios mecánicos el café cereza recién cosechado, se diseñó y construyó un transportador en el Centro Nacional de Investigaciones de café “CENICAFE” ubicado en el municipio de Chinchiná (Caldas, empleando un cable aéreo, proyectado para que enviara el café cereza a granel desde el sitio de cargue (parte baja del terreno hasta el sitio de descargue (parte alta localizada en el beneficiadero experimental . El medio de tracción es un cable tractor "abierto" unido por un extremo al lomo de fuerza motriz y por el otro a la carga. Se aprovechó la pendiente del terreno para enviar, por gravedad, la vagoneta al lugar de cargue. El control de velocidad de descenso se hizo a través del freno del malacate El transportador se diseñó para superar pendientes del 30 % con una carga total de 300 kg (24 @, de los cuales 175 kg (14 @ corresponden al peso del café cereza y los 125 kg (10 @ restantes al peso de la vagoneta. La longitud de recorrido del transportador es de 180 m y la velocidad de traslación de la vagoneta cargada es de 1.3 m.s2 El ciclo completo de cargue y descargue del material es de unos 400 s; por lo tanto, la capacidad del transportador es de 1.6 * 10 kg.h^-1 Las características topográficas del terreno y el espacio disponible, hicieron necesario orientar el cable aéreo portante en tres sentidos, con pendientes y tramos diferentes. Se identificó el cable aéreo como el elemento principal del estudio, razón por la cual se determinaron las tensiones y desplazamientos en el mismo utilizando para ello un programa desarrollado durante el trabajo (programa "CABLE. BAS " . Con base en los resultados obtenidos, fueron dimensionados los elementos principales

  7. Unimolecular fragrmentations of the radical cation of the high-valent organometal oxide CH3ReO3 and its reactivity with ethylene in the gas phase

    Science.gov (United States)

    Schröder, Detlef; Herrmann, W. A.; Fischer, Richard W.; Schwarz, Helmut

    1992-12-01

    The unimolecular chemistry of CH3ReO[radical sign]+3 in the gas phase commences with a methyl migration to' generate CH3 OReO[radical sign]+2. This further undergoes multiple hydrogen migration to the metal centre to generate an intermediate which serves as a precursor for the elimination of both molecular hydrogen and of carbon monoxide. If CH3ReO[radical sign]+3 is reacted with ethylene, inter alia products are observed which point to a competition between an intramolecular metathesis reaction of the ethylene-inserted intermediate CH3CH2CH2ReO3[radical sign]+ and epoxidation of ethylene to generate c-C2H4O.

  8. Implementação de modelo para balanceamento de fluxos aplicado ao gerenciamento de tráfego aéreo

    OpenAIRE

    Bueno Borges de Souza; Li Weigang; Antonio Marcio Ferreira Crespo

    2009-01-01

    Este trabalho descreve um sistema de auxílio à decisão com metodologias de Teoria dos Grafos e Inteligência Artificial para dar suporte ao Gerenciamento de Fluxo de Tráfego Aéreo Brasileiro. Trata-se de um modelo de gerenciamento de fluxo baseado em grafos com adaptações heurísticas para a regulação dinâmica do fluxo. O modelo fundamen...

  9. Caracterización de vidrios para la evaluación del aislamiento acústico a ruido aéreo

    Directory of Open Access Journals (Sweden)

    Alba Fernández, J.

    2012-08-01

    Full Text Available The main contribution of this paper is the formulation of an alternative to experimental determination of loss factor and, consequently, to improve the predictions of airborne sound insulation for any type of monolithic or laminated glass. In addition, a review of the standards related to measurement of mechanical parameters of glass is carried out, with particular interest in laminated glass. Indeed, one of the problems that arise in the current context of building acoustics is to meet the requirements of facades airborne sound insulation of existing Building Technical Code (BTC. It is known that the blind and the hollow part of the facade should be distinguished. The weakest part regarding to airborne sound insulation is the empty one (consisting of glass, woodwork and other elements. Choosing an adequate woodwork makes the glass surface become the limiting factor. The Constructive Elements Catalog (CEC of the BTC, the UNE-EN 12758:2011 standard, as well as some, increasingly, data vendors provide information about airborne sound insulation for monolithic glass, laminated glass and double glazing. In the case of laminated glass, these data are limited only to those with a single intermediate layer, and also nonacoustic. Can therefore be said that there is a gap of knowledge in this regard. To obtain reliable predictions of airborne sound insulation of multilayer partitions, such as laminated glass, mechanical characteristics must be known, being loss factor one of the most important.

    La principal aportación del trabajo es la formulación de una alternativa que facilita la determinación experimental del factor de pérdidas y, en consecuencia, mejorar las predicciones de aislamiento a ruido aéreo para vidrios con una o más capas intermedias sea cual fuere su naturaleza. Además, se realiza una revisión de las normativas relacionadas con los ensayos de los parámetros mecánicos necesarios para la caracterizar los vidrios, centr

  10. Schreibende Messgeräte

    Science.gov (United States)

    Plaßmann, Wilfried

    Die schreibenden Messgeräte werden hauptsächlich eingesetzt, um Vorgänge aufzuzeichnen und zu dokumentieren, die sich im Minuten- und Stunden-Bereich abspielen. Sie sind weitgehend durch Oszilloskope oder elektronische Geräte ähnlich einem Oszilloskop ersetzt worden, die entsprechend für Langzeitaufnahmen ausgelegt sind. Der Vorteil dieser Geräte gegenüber den schreibenden Messgeräten ist der, dass die Daten dauerhaft gespeichert sind, einschließlich der notwendigen Kenngrößen wie Zeitmaßstab, Amplitude, Datum, Aufzeichnungsgerät usw., und sich in dieser Form beliebig oft ausdrucken und vor allem direkt weiterverarbeiten lassen. Weiterhin entfallen die Probleme mit der Mechanik, dem Papier und den Schreibstiften. Deshalb folgt hier eine nur kurze Darstellung der Geräte.

  11. Gamma transitions in 127Te

    International Nuclear Information System (INIS)

    Batista, Wagner Fonseca; Zamboni, Cibele Bugno

    2009-01-01

    This study of the 127 Te β - decay was carried out by means of gamma spectroscopy measurements using high resolution Ge detector, in the region from 150 keV up to 1000 keV, aiming to get a better understanding of the 127 Te nuclear structure. Several gamma transitions were confirmed when compared with those published in the last compilation. These data resulting in lower uncertainty. (author)

  12. La política y legislación forestal nicaragüense: implicaciones para el fomento y aprovechamiento arbóreo en fincas ganaderas

    Directory of Open Access Journals (Sweden)

    Yuri Marín

    2007-08-01

    Full Text Available ESTE ESTUDIO VINCULA LA PROBLEMÁTICA FORESTAL Y AMBIENTAL A NIVEL MICRO con el nivel de políticas más sectorial a través de un estudio de caso y consulta a expertos locales y nacionales. Aporta al conocimiento de las principales barreras legales e institucionales que impiden a los finqueros ganaderos fomentar y aprovechar mejor el recurso arbóreo en sus fincas. Identifica medidas de políticas y ajustes al marco legal forestal que podrían contribuir a favorecerlo. El estudio discute sobre el desconocimiento de la legislación forestal del país entre los finqueros y una falta de coordinación entre los actores institucionales, INAFOR y alcaldías, en relación con la gestión del recurso y el otorgamiento de permisos para aprovechamiento, lo que favorece la ilegalidad y la no sostenibilidad de los recursos forestales. Se concluye que en zonas ganaderas del interior existe un potencial de aprovechamiento forestal que puede ser explotado de manera sostenible si se dirige la atención a mejorar los conocimientos del marco regulatorio, la capacidad de manejo técnico del recurso arbóreo en fincas, el entrenamiento en el manejo de la legislación y los procedimientos para el aprovechamiento forestal, y la articulación entre el INAFOR y las municipalidades en un marco de descentralización

  13. Uma nova capacidade de distribuição e um novo ciclo no transporte aéreo

    OpenAIRE

    Nabais, Paulo Alexandre Gonçalves

    2016-01-01

    Hoje em dia as companhias aéreas debatem-se com a problemática dos custos de distribuição que têm, principalmente pelo canal indireto, ou seja através dos sistemas de reserva. O presente trabalho tem como o objetivo estudar as várias estratégias que as Companhias Aéreas têm à sua disposição, e estudar quais serão os comportamentos estratégicos dos vários intervenientes no mercado com a entrada do New Distribution Capability. Numa primeira parte é feito um estudo teórico acerca das vária...

  14. La política comunitaria del cielo único europeo : reflexiones sobre su impacto en el principio de soberanía : repercusiones en la política de liberalización del transporte aéreo : principios y mecanismos de estructuración

    OpenAIRE

    Ospina Mosquera, Norma Constanza

    2011-01-01

    En los procesos de liberalización al interior de la integración europea, la liberalización del transporte aéreo significó un gran avance en la consolidación del mercado único. Sin embargo esta liberalización trajo consigo congestión en el espacio aéreo, situación que repercutió en la seguridad y eficiencia del sistema y conllevó a su vez la falta de competitividad de los mercados. Las causas de dicha ineficiencia tienen su origen en una organización del espacio aéreo irrac...

  15. La política comunitaria del cielo único europeo : reflexiones sobre su impacto en el principio de soberanía : repercusiones en la política de liberalización del transporte aéreo : principios y mecanismos de estructuración

    OpenAIRE

    Ospina Mosquera, Norma Constanza

    2005-01-01

    En los procesos de liberalización al interior de la integración europea, la liberalización del transporte aéreo significó un gran avance en la consolidación del mercado único. Sin embargo esta liberalización trajo consigo congestión en el espacio aéreo, situación que repercutió en la seguridad y eficiencia del sistema y conllevó a su vez la falta de competitividad de los mercados. Las causas de dicha ineficiencia tienen su origen en una organización del espacio aéreo irrac...

  16. Optical phonons in PbTe/CdTe multilayer heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Novikova, N. N.; Yakovlev, V. A. [Russian Academy of Sciences, Institute for Spectroscopy (Russian Federation); Kucherenko, I. V., E-mail: kucheren@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Karczewski, G. [Polish Academy of Sciences, Institute of Physics (Poland); Aleshchenko, Yu. A.; Muratov, A. V.; Zavaritskaya, T. N.; Melnik, N. N. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2015-05-15

    The infrared reflection spectra of PbTe/CdTe multilayer nanostructures grown by molecular-beam epitaxy are measured in the frequency range of 20–5000 cm{sup −1} at room temperature. The thicknesses and high-frequency dielectric constants of the PbTe and CdTe layers and the frequencies of the transverse optical (TO) phonons in these structures are determined from dispersion analysis of the spectra. It is found that the samples under study are characterized by two TO phonon frequencies, equal to 28 and 47 cm{sup −1}. The first frequency is close to that of TO phonons in bulk PbTe, and the second is assigned to the optical mode in structurally distorted interface layers. The Raman-scattering spectra upon excitation with the radiation of an Ar{sup +} laser at 514.5 nm are measured at room and liquid-nitrogen temperatures. The weak line at 106 cm{sup −1} observed in these spectra is attributed to longitudinal optical phonons in the interface layers.

  17. Kaupapa Maori, Philosophy and Schools

    Science.gov (United States)

    Stewart, Georgina

    2014-01-01

    Goals for adding philosophy to the school curriculum centre on the perceived need to improve the general quality of critical thinking found in society. School philosophy also provides a means for asking questions of value and purpose about curriculum content across and between subjects, and, furthermore, it affirms the capability of children to…

  18. Superstrengthening Bi2Te3 through Nanotwinning

    Science.gov (United States)

    Li, Guodong; Aydemir, Umut; Morozov, Sergey I.; Wood, Max; An, Qi; Zhai, Pengcheng; Zhang, Qingjie; Goddard, William A.; Snyder, G. Jeffrey

    2017-08-01

    Bismuth telluride (Bi2Te3 ) based thermoelectric (TE) materials have been commercialized successfully as solid-state power generators, but their low mechanical strength suggests that these materials may not be reliable for long-term use in TE devices. Here we use density functional theory to show that the ideal shear strength of Bi2Te3 can be significantly enhanced up to 215% by imposing nanoscale twins. We reveal that the origin of the low strength in single crystalline Bi2Te3 is the weak van der Waals interaction between the Te1 coupling two Te 1 - Bi - Te 2 - Bi - Te 1 five-layer quint substructures. However, we demonstrate here a surprising result that forming twin boundaries between the Te1 atoms of adjacent quints greatly strengthens the interaction between them, leading to a tripling of the ideal shear strength in nanotwinned Bi2Te3 (0.6 GPa) compared to that in the single crystalline material (0.19 GPa). This grain boundary engineering strategy opens a new pathway for designing robust Bi2Te3 TE semiconductors for high-performance TE devices.

  19. Comprehensive thermodynamic description of the quasiternary system PbTe-GeTe-SnTe

    International Nuclear Information System (INIS)

    Yashina, Lada V.; Leute, Volkmar; Shtanov, Vladimir I.; Schmidtke, Heinrich M.; Neudachina, Vera S.

    2006-01-01

    The equilibrium phase diagram of the quasiternary system PbTe-GeTe-SnTe was studied experimentally in the ranges of spinodal demixing and (solid + liquid) equilibrium by means of X-ray diffraction (XRD), electron microprobe analysis (EMA) and differential thermal analysis (DTA). A model description of the phase diagram was done on the base of composition dependent interaction parameters, which were determined for the solid and the liquid phases. The interaction parameters for the quasibinary systems were recalculated in order to reach better correlation between all experimental data. It was shown that the quasiternary phase diagram can be principally described using the interaction parameters for the quasibinary subsystems, but an additional ternary interaction parameter has also to be considered. The local structure of the quasiternary solid solution is described by a four-particle cluster model. Due to the tendency of the solid solution to demix, the probability of the (GeGeGe)Te cluster was found to be higher and that of the (PbGeGe)Te cluster to be lower than it is expected for the purely statistical distribution of the clusters

  20. M rate at TE. Monitoring at TeV energies

    Energy Technology Data Exchange (ETDEWEB)

    Dorner, Daniela [Universitaet Wuerzburg (Germany); Bretz, Thomas [RWTH Aachen (Germany); Gonzalez, Magdalena; Alfaro, Ruben [Universidad Nacional Autonoma de Mexico (Mexico); Tovmassian, Gagik [Instituto de Astronomia Sede Ensenada (Mexico)

    2016-07-01

    A dedicated long-term monitoring programm at TeV energies has been started by the FACT project about four years ago. Being limited to one site, gaps due to the rotation of the Earth remain in the measured light curves. This makes it difficult to study typical variability time scales of few hours to one day. To allow for systematic studies of continuous observations over up to 12 hours, a second telescope is being installed at a site in about six hours distance in longitude. For the M rate at TE (Monitoring at TeV energies) telescope, a mount from a previous experiment is being refurbished and will be equipped with a new camera. Using silicon based photo sensors like in FACT, an excellent and stable performance will be achieved. M rate at TE is a joint project of German and Mexican universities which aims at extending the blazar monitoring to so far unexplored time ranges. In the presentation, the status of this emerging project is reported.

  1. Ausência de fluxo aéreo nasal e desenvolvimento dos seios maxilares Absence of nasal air flow and maxillary sinus development

    Directory of Open Access Journals (Sweden)

    Roberto Eustáquio dos Santos Guimarães

    2007-04-01

    Full Text Available Os mecanismos responsáveis pelo desenvolvimento dos seios paranasais ainda são pouco conhecidos, o fluxo aéreo nasal segundo uma das teorias propostas seria fundamental ao crescimento e desenvolvimento saudável dos seios paranasais. OBJETIVO: Estudar comparativamente o desenvolvimento dos seios maxilares e a presença de sinusopatia, em um mesmo modelo, na ausência e presença de fluxo aéreo nasal posterior. MATERIAL E MÉTODOS: Estudo retrospectivo transversal de uma série de casos; os exames tomográficos pré-operatórios de 7 pacientes com atresia coanal unilateral, idade média 16.28 anos (± 5,024. Este estudo realizado em um hospital terciário, com pacientes que passaram neste serviço entre os anos de 1994 e 2004. A área dos seios maxilares foi medida com auxílio do programa Auto-Cad. Utilizou-se o teste de Kruskal-Wallis para análise estatística. RESULTADOS: Nesse estudo observou-se seios maxilares simétricos e até mesmo maiores no lado da atresia coanal em 85,71% dos casos, não houve diferença estatística significativa entre os dois lados comparados. Não se observou sinais de tomográficos de sinusopatia neste grupo de pacientes. CONCLUSÃO: Os achados aqui apresentados contrariam a teoria difusamente aceita sobre o papel do fluxo aéreo nasal na saúde e no desenvolvimento das cavidades paranasais.Paranasal sinuses development mechanisms are not well known. Nasal air flow, according to one of the proposed theories, would be fundamental to the growth and healthy development of paranasal sinuses. AIM: The aim of this study was to evaluate the maxillary sinus growth and health in the presence and absence of postnasal air flow through a unique model. MATERIALS AND METHODS: Retrospective study of a series of cases; preoperative CT scans of 7 patients with unilateral choanal atresia, average age was 16.28 years (± 5.024. This study was done in a tertiary hospital, with patients treated between 1994 and 2004. The area of

  2. El aborto y delito de violación sexual en el 44° Juzgado Penal con reos en cárcel del distrito judicial de Lima, 2014

    OpenAIRE

    Mandujano Santivañez, Víctor Edy; Muñoz Gutiérrez, Omar; Zamora Hidalgo, Edwin

    2015-01-01

    La presente tesis lleva por título “El aborto y el delito de violación sexual en el 44° Juzgado Penal con reos en cárcel del distrito judicial de Lima, 2014” y tiene como propósito describir la percepción de los abogados sobre el aborto y el delito de violación sexual en el 44 Juzgado Penal con reos en cárcel del distrito judicial de Lima. El diseño de investigación es no experimental con un enfoque cuantitativo y tipo de investigación descriptiva, cuyos resultados se eviden...

  3. Constraining the dynamic response of subcontinental lithospheric mantle to rifting using Re-Os model ages in the Western Ross Sea, Antarctica

    Science.gov (United States)

    Doherty, C.; Class, C.; Goldstein, S. L.; Shirey, S. B.; Martin, A. P.; Cooper, A. F.; Berg, J. H.; Gamble, J. A.

    2012-12-01

    In order to understand the dynamic response of the subcontinental lithospheric mantle (SCLM) to rifting, it is important to be able to distinguish the geochemical signatures of SCLM vs. asthenosphere. Recent work demonstrates that unradiogenic Os isotope ratios can indicate old depletion events in the convecting upper mantle (e.g. Rudnick & Walker, 2009), and allow us to make these distinctions. Thus, if SCLM can be traced across a rifted margin, its fate during rifting can be established. The Western Ross Sea provides favorable conditions to test the dynamic response of SCLM to rifting. Re-Os measurements from 8 locations extending from the rift shoulder to 200 km into the rift basin reveal 187Os/188Os ranging from 0.1056 at Foster Crater on the shoulder, to 0.1265 on Ross Island within the rift. While individual sample model ages vary widely throughout the margin, 'aluminochron' ages (Reisberg & Lorand, 1995) reveal a narrower range of lithospheric stabilization ages. Franklin Island and Sulfur Cones show a range of Re-depletion ages (603-1522 Ma and 436-1497 Ma) but aluminochrons yield Paleoproterozoic stabilization ages of 1680 Ma and 1789 Ma, respectively. These ages coincide with U-Pb zircon ages from Transantarctic Mountain (TAM) crustal rocks, in support of SCLM stabilization at the time of crust formation along the central TAM. The Paleoproterozoic stabilization age recorded at Franklin Island is especially significant, since it lies 200km off of the rift shoulder. The similar ages beneath the rift shoulder and within the rift suggests stretched SCLM reaches into the rift and thus precludes replacement by asthenospheric mantle. The persistence of thinned Paleoproterozoic SCLM into the rifted zone in WARS suggests that it represents a 'type I' margin of Huismans and Beaumont (2011), which is characterized by crustal breakup before loss of lithospheric mantle. The Archean Re-depletion age of 3.2 Ga observed on the rift shoulder suggests that cratonic

  4. Graptolite graveyard: Re-Os dating of macroplankton at the Lower-Middle Ordovician boundary (Floian-Dapingian stage boundary), Tøyen Shale, southern Sweden

    Science.gov (United States)

    Goswami, V.; Stein, H. J.; Hannah, J. L.; Ahlberg, P.; Maletz, J.

    2017-12-01

    There exist only 16 radiometric ages for the entire 42 m.y. Ordovician Period. Stage boundaries are biostratigraphically defined by the first appearance of agreed on graptolite and conodont species. Cosmopolitan graptolites are common in the Ordovician and their relatively brief stratigraphic durations make them ideal for global correlations. The Floian-Dapingian stage boundary (Lower-Middle Ordovician boundary) is very poorly constrained, with an absence of radiometric dates for several million years below the boundary and poor statistics on ages in the lower Dapingian [1]. Here we use the Ordovician Tøyen Shale, widespread across southern Sweden and Norway with a highly-refined graptolite biostratigraphy, to add a new age constraint [2]. With drill core from Lerhamn, Sweden (samples from 35.75-36.70 m depth), we employ a novel approach to directly date the fauna. We physically extracted a well-preserved 5-cm fossil of macroplankton (graptolite) from organic-rich shales (up to 4% TOC) for Re-Os dating. The graptolite and its hosting shale together define a well-constrained Model 1 isochron of 469.4 ± 1.7 Ma (2s, MSWD = 1.7, n = 9) and an initial 187Os/188Os (Osi) of 0.802 ± 0.002 for seawater. The Osi documents sustained radiogenic Os input to seawater from the Neoproterozoic-Cambrian through the Early Ordovician, in concert with the Sr isotope seawater curve. The analyzed graptolite belongs to the species Pseudophyllograptus augustifolius, a member of the upper Floian fauna [2]. Our nominal age for the dated graptolite and the shale is lower Dapingian according to the 2017 GTS [1]. Therefore, the Re-Os age suggests the Floian-Dapingian stage boundary may be younger than currently accepted. As defined in the GTS, the Dapingian stage is only 2.7 m.y. (470.0 ± 1.4 to 467.3 ± 1.1 Ma); combined uncertainties could give the Dapingian a mere 0.2 m.y. duration (or a maximum of 5 m.y). Although uncertainties overlap, our first dating of the Lower-Middle Ordovician

  5. Molybdenum mineralization at Alpeiner Scharte, Tyrol (Austria): results of in-situ U-Pb zircon and Re-Os molybdenite dating

    International Nuclear Information System (INIS)

    Langthaler, K.J.; Raith, J.G.; Cornell, D.H.; Stein, H.J.; Melcher, F.

    2004-01-01

    Vein-type Mo mineralization at Alpeiner Scharte occurs in the Penninic units of the western Tauern Window in the Eastern Alps. Three types of previously undated metagranitoids (central gneisses) are distinguished and preserve intrusive contacts with pre-Alpine metamorphosed supracrustal rocks. The granitic protoliths represent fractionated late to post-orogenic, calc-alkaline, I-type magmas with minor S-type components. The Mo veins are restricted to a biotite and alkali feldspar-rich gneiss variety and occur in E-W trending normally sub-vertical quartz veins with adjacent thin discontinuous garnet- and biotite-rich zones; the latter are interpreted as metamorphosed vein selvages. Prior to this work the age of the intrusive host rocks as well as the age of Mo mineralization were unknown. The pre-Alpine Mo deposit and its host rocks were affected by four Alpine deformation events (D 1 -D 4 ) and Young-Alpine regional metamorphism. The P-T conditions of this metamorphic event were ∼ 550 o C and ∼ 8 kbar and are in agreement with results of previous regional studies. Zircon grains from two orthogneiss samples were dated with the U-Pb method using ion probe techniques. Zircons from the metagranitic host rock of the Mo-veins yielded an emplacement age of 306.8 ± 3.8 Ma (2σ). A second sample from a more leucocratic gneiss lacking Mo-veins gave 305.0 ± 6.6 Ma (2 σ). Re-Os dating of molybdenite from the veins yielded an age of 306.8 ± 3.1 Ma in good agreement with the U-Pb zircon ages. This study confirms one of two alternative hypotheses discussed in the literature. lt supports the idea that vein-type Mo-mineralization in the western Tauern Window is genetically related to Late Carboniferous (Westphalian) granitoids that were emplaced during the late to post-orogenic stage of the Variscan orogeny. They do not constitute an Alpine metamorphic-hydrothermal deposit. This study further confirms the strength of the Re-Os molybdenite chronometer, in that it was

  6. Molybdenite Re-Os, zircon U-Pb dating and Lu-Hf isotopic analysis of the Xiaerchulu Au deposit, Inner Mongolia Province, China

    Science.gov (United States)

    Wang, Jia-xin; Nie, Feng-Jun; Zhang, Xue-ni; Jiang, Si-hong

    2016-09-01

    The Xiaerchulu Au deposit, located in the Southern Orogenic Belt (SOB) of Western Inner Mongolia (WIM), is hosted in an Early Permian (271-261 Ma) volcanic-plutonic sequence. Mineralization took place in silicified biotite granites or along the contact zone between the Neoproterozoic Baiyinbaolage Group and the biotite granite. In order to constrain the timing of the Xiaerchulu mineralization and discuss the petrogenesis of the hosting granites, molybdenite Re-Os, and zircon U-Pb and, Lu-Hf, and REE, geochemical, and Sr-Nd isotopic studies were completed in this study. We measured Re-Os isotopes of six molybdenite samples from the main ore body, which yielded a weighted average model age of 261.7 ± 1.5 Ma with a MSWD of 0.55, indicating that the time of mineralization was at ca. 262 Ma. High precision U-Pb dating for the studied granites yields Permian 206Pb/238U ages ranging from 271 to 269 Ma. These age data confirm that both the intrusion and related mineralization were initiated in Early Permian period. These granites are strongly peraluminous with A/CNK = 1.11-1.12, high SiO2-K2O contents, as well as containing biotite and muscovite, indicating a petrogenesis of typical S-type granites, the above consideration is also consistent with the result of discrimination diagrams. The Re contents of molybdenite, εNd(t), and zircon εHf(t), as well as the 176Hf/177Hf values of the granites, fall into the ranges from 1.153 to 2.740 μg/g, - 11.1 to - 9.3, - 8.8 to - 0.9, and 0.282358 to 0.282688, respectively. All of this evidence suggests that the metals were derived from a predominantly crustal source, the granites originated from crust in an extensional setting, and the rejuvenation of the continent may have play an important role during the ore-forming processes of the Early Permian epoch.

  7. Re-Os systematics of komatiites and komatiitic basalts at Dundonald Beach, Ontario, Canada: Evidence for a complex alteration history and implications of a late-Archean chondritic mantle source

    Science.gov (United States)

    Gangopadhyay, Amitava; Sproule, Rebecca A.; Walker, Richard J.; Lesher, C. Michael

    2005-11-01

    Osmium isotopic compositions, and Re and Os concentrations have been examined in one komatiite unit and two komatiitic basalt units at Dundonald Beach, part of the 2.7 Ga Kidd-Munro volcanic assemblage in the Abitibi greenstone belt, Ontario, Canada. The komatiitic rocks in this locality record at least three episodes of alteration of Re-Os elemental and isotope systematics. First, an average of 40% and as much as 75% Re may have been lost due to shallow degassing during eruption and/or hydrothermal leaching during or immediately after emplacement. Second, the Re-Os isotope systematics of whole rock samples with 187Re/ 188Os ratios >1 were reset at ˜2.5 Ga, possibly due to a regional metamorphic event. Third, there is evidence for relatively recent gain and loss of Re in some rocks. Despite the open-system behavior, some aspects of the Re-Os systematics of these rocks can be deciphered. The bulk distribution coefficient for Os (D Ossolid/liquid) for the Dundonald rocks is ˜3 ± 1 and is well within the estimated D values obtained for komatiites from the nearby Alexo area and stratigraphically-equivalent komatiites from Munro Township. This suggests that Os was moderately compatible during crystal-liquid fractionation of the magmas parental to the Kidd-Munro komatiitic rocks. Whole-rock samples and chromite separates with low 187Re/ 188Os ratios (Gorgona Island, arc-related rocks and present-day ocean island basalts. This suggests that the Kidd-Munro komatiites sampled a late-Archean mantle source region that was significantly more homogeneous with respect to Re/Os relative to most modern mantle-derived rocks.

  8. Catalysts for selective hydrogenation of furfural derived from the double complex salt [Pd(NH 3 ) 4 ](ReO 4 ) 2 on γ-Al 2 O 3

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Simon T.; Lamb, H. Henry

    2017-06-01

    The double complex salt [Pd(NH3)4](ReO4)2 was employed as precursor of supported bimetallic catalysts for selective hydrogenation of furfural. Direct reduction of [Pd(NH3)4](ReO4)2 on γ-Al2O3 in flowing H2 at 400 °C yields bimetallic nanoparticles 1–2 nm in size that exhibit significant interaction between the metals, as evidenced by temperature-programmed hydride decomposition (complete suppression of β-PdHx formation), extended X-ray absorption fine structure spectroscopy at the Pd K and Re LIII edges (PdRe distance = 2.72 Å), and scanning transmission electron microscopy with energy dispersive X-ray analysis. In contrast, calcination of [Pd(NH3)4](ReO4)2 on γ-Al2O3 at 350 °C in air and subsequent reduction in H2 at 400 °C results in metal segregation and formation of large (>50 nm) supported Pd particles; Re species cover the Pd particles and γ-Al2O3 support. A PdRe 1:2 catalyst prepared by sequential impregnation and calcination using HReO4 and [Pd(NH3)4](NO3)2 has a similar morphology. The catalyst derived by direct reduction of [Pd(NH3)4](ReO4)2 on γ-Al2O3 exhibits remarkably high activity for selective hydrogenation of furfural to furfuryl alcohol (FAL) at 150 °C and 1 atm. Suppression of H2 chemisorption via elimination of Pd threefold sites, as evidenced by CO diffuse-reflectance infrared Fourier transform spectroscopy, correlates with increased FAL selectivity.

  9. A multi-radioisotope approach to dating sedimentation : applying Re-Os organic-rich shale and U-Pb authigenic xenotime dating to the Shannon and Pennine Basins

    OpenAIRE

    Stanislawska, Maja Anna

    2013-01-01

    Sedimentary rocks are the most abundant hthologies on the Earth, covering over 70% of the planet’s surface. Quantitative dating of sedimentary rocks (especially those devoid of fossils) is critical to understanding the past events and rates and duration of processes that shaped the Earth. Recent advances in geochronology of sedimentary rocks, such as Re-Os dating of organic-rich shales and U-Pb dating of authigenic xenotime, allow precise depositional and early diagenetic ages to be obtained,...

  10. Programa para la implementación del sistema de gestión de riesgos laborales con la Norma OHSAS 18000, en el taller de láminas y estructuras del Comando Aéreo de Transporte Militar

    Directory of Open Access Journals (Sweden)

    Leonardo Garzón Bernal

    2006-01-01

    Full Text Available En el comando Aéreo de Transporte Militar no existe una organización ágil de los procesos estandarizados, ya que se han presentado setenta incidentes laborales en promedio por año con lesiones para el personal en un 28%  que corresponden a los operarios del taller, de acuerdo con las estadísticas del departamento de seguridad.

  11. Te hard van stapel gelopen.

    NARCIS (Netherlands)

    W-J. Verhoeven (Willem-Jan)

    2008-01-01

    textabstractHoe goed we ook trachten de samenleving te organiseren, fraude maakt er deel van uit. Dit blijkt uit spraakmakende grote schandalen zoals de Enron-zaak, de Bouwfraude-zaak en de Nigerian letter scams. Maar fraude komt ook op minder geruchtmakende schaal voor, zoals oplichting op

  12. X = S, Se, Te) heterostructures

    KAUST Repository

    Zhang, Qingyun; Schwingenschlö gl, Udo

    2018-01-01

    Using first-principles calculations, we investigate the electronic properties of the two-dimensional GaX/MX2 (M = Mo, W; X = S, Se, Te) heterostructures. Orbital hybridization between GaX and MX2 is found to result in Rashba splitting at the valence

  13. Desorption of Te capping layer from ZnTe (100): Auger spectroscopy ...

    African Journals Online (AJOL)

    ... configurations of tellurium Te (c (2x2)) and Te (c (2x1)) are confirmed by scanning tunneling microscopy (STM). Such a study reveals a phase transition from a rich-Te to a poor-Te surface as the annealing temperature increases. Keywords: Zinc Tellure; solar cells; structural properties; optoelectronics; semiconductors.

  14. S and Te inter-diffusion in CdTe/CdS hetero junction

    Energy Technology Data Exchange (ETDEWEB)

    Enriquez, J. Pantoja [Cuerpo Academico-Energia y Sustentabilidad, Universidad Politecnica de Chiapas, Eduardo J. Selvas S/N, Col. Magisterial, Tuxtla Gutierrez 29010, Chiapas (Mexico); Gomez Barojas, E. [CIDS-ICUAP, Apdo. Postal 1651, 72000 Puebla (Mexico); Silva Gonzalez, R.; Pal, U. [Instituto de Fisica, Benemerita Universidad Autonoma de Puebla, Puebla (Mexico)

    2007-09-22

    Effects of post formation thermal annealing of the CdTe-CdS device on the inter-diffusion of S and Te at the junction in a substrate configuration device have been studied by Auger electron spectroscopy. While the migration of S and Te atoms increases with annealing temperature, the extent of S diffusion is always higher than the diffusion of Te atoms. Inter-diffusion of S and Te causes the formation of CdTe{sub 1-x}S{sub x} ternary compound at the CdTe-CdS interface. (author)

  15. Near-infrared emission bands of TeH and TeD

    Science.gov (United States)

    Fink, E. H.; Setzer, K. D.; Ramsay, D. A.; Vervloet, M.

    1989-11-01

    High-resolution emission spectra of TeH and TeD have been obtained in the region 4200 to 3600 cm -1 using a Bomem DA3.002 Fourier transform spectrometer. Analyses are given for the 0-0 and 1-1 bands of the X 22Π{1}/{2}-X 12Π{3}/{2} system of TeH and for the 0-0 band of TeD. In addition the 2-0 vibrational overtone bands of 130TeH, 128TeH, and 126TeH are observed and analyzed. Accurate molecular constants are given for the first time.

  16. Study of Te Inclusions in CdMnTe Crystals for Nuclear Detector Applications

    International Nuclear Information System (INIS)

    Babalola, O.S.; Bolotnikov, A.; Groza, M.; Hossain, A.; Egarievwe, S.; James, R.; Burger, A.

    2009-01-01

    The concentration, size and spatial distribution of Te inclusions in the bulk of CdMnTe crystals mined from two batches of ingots were studied. An isolated planar layer decorated with Te inclusions was identified in CdMnTe crystals from the second ingot. The internal electric field of a CMT crystal was probed by infrared (IR) imaging employing Pockels electro-optic effect. The effect of an isolated plane of Te inclusions on the internal electric-field distribution within the CdMnTe crystal was studied. Space charge accumulation around the plane of Te inclusions was observed, which was found to be higher when the detector was reverse-biased. The effects of the plane of Te inclusions on the electric-field distribution within the CdMnTe crystal, and the quality of CdMnTe crystals for nuclear detector applications are discussed.

  17. Liquidus surface of the triple reciprocal system PbTe+CdS↔PbS+CdTe

    International Nuclear Information System (INIS)

    Tomashik, Z.F.; Tomashik, V.N.

    1987-01-01

    Using differential-thermal and microstructural analyses and mathematical design interaction in PbTe-CdS system is studied. Liquidus surface of the triple reciprocal system PbTe+CdS↔PbS+CdTe is plotted. It is shown that PbTe-CdS system phase diagram is of eutectic type. Maximal solubility of CdS in PbTe attains 13 mol%, and of PbTe in CdS is not over 1 mol%. Projection of liquidus surface of the PbTe+CdS↔PbS+CdTe triple reciprocal system consists of two primary crystallization fields: CdTe x S 1-x and PbTe x S 1-x solid solutions separated by eutectic line

  18. MEDIAÇÃO EXTRAJUDICIAL E INDENIZAÇÃO POR ACIDENTE AÉREO: RELATO DE UMA EXPERIÊNCIA BRASILEIRA

    Directory of Open Access Journals (Sweden)

    Fernanda Tartuce

    2012-07-01

    Full Text Available Resumo: O artigo aborda a experiência da autora como observadora no programa de indenização 447, iniciativa que integrou autoridades, familiares e empresas para propiciar a composição das controvérsias pelo desastre aéreo ocorrido em 30 de maio de 2009, no voo 447 (Rio-Paris da empresa Air France. Após descrever o programa, o artigo discute como a mediação foi utilizada para abordar os impasses entre os envolvidos, buscando promover a comunicação em bases eficientes e produtivas.Abstract: The article discusses the author’s experience as observer in the indemnification program n. 447, which brought together authorities, families and companies in order to promote the composition of disputes involving the plane crash occurred in May 30th, 2009 – Air France’s flight n. 447 (Rio-Paris. After describing the program, it discusses how mediation was used to approach the disputes between the characters involved, aiming to promote communication on efficient and productive basis.

  19. Multiphase formation of the Obří důl polymetallic skarn deposit, West Sudetes, Bohemian Massif: geochemistry and Re-Os dating of sulfide mineralization

    Science.gov (United States)

    Veselovský, František; Ackerman, Lukáš; Pašava, Jan; Žák, Karel; Haluzová, Eva; Creaser, Robert A.; Dobeš, Petr; Erban, Vojtěch; Tásler, Radko

    2018-06-01

    The Obří důl Fe-Cu-As polymetallic sulfide skarn deposit is developed in a metamorphic series in the West Sudetes, Bohemian Massif. It consists of lenses of marble, calc-silicate rocks, and skarns. We studied the Gustav orebody, which is located few hundred meters away from the contact with a large, late-orogenic Variscan Krkonoše-Jizera Plutonic Complex (KJPC) emplaced into shallow crust. Mineralogical and fluid inclusion study evidence indicates that the main sulfide stage, dominated by pyrrhotite, arsenopyrite, and chalcopyrite originated from aqueous hydrothermal fluids with salinity up to 8 wt% NaCl eq. with minimum homogenization temperatures ranging from 324 to 358 °C. These fluids mainly replaced carbonate-rich lithologies. Carbon, oxygen, and strontium isotope data in Ca-rich rocks imply total overprinting by channelized metasomatic fluid flow, which is most probably related to the intrusion of the KJPC, whereas δ34S values of sulfides argue for a magmatic source of sulfur. The Re-Os age of arsenopyrite overlaps published age data for the KJPC and suggests synchronous formation of the main sulfide mineralization and pluton emplacement.

  20. Extracto etéreo de frutos de Bromelia pinguin L. (piña de ratón por el sistema acoplado CG-EM

    Directory of Open Access Journals (Sweden)

    Juan Abreu Payrol

    2001-04-01

    Full Text Available Se realizó el estudio del extracto etéreo de frutos de Bromelia pinguin L. (piña de ratón mediante el sistema acoplado CG-EM. Se detectó la presencia de los ácidos 2-pentenodioico, octanodioico, ftálico, cítrico, nonanodioico, 12-metiltetradecanoico, palmítico, oleico, linolénico, esteárico, 11,14,17-eicosatrienoico y 11,14-eicosadienoico. La identificación fue realizada sobre la base de los tiempos de retención y fue confirmada por comparación de los espectros de masas con los de patrones. Por primera vez es informada la presencia de estos compuestos en los frutos de B. pinguin L.The study of the ethereal extract from fruits of Bromelia pinguin L. ("piña de ratón" was conducted by the CG-EM coupled system. The following acids were detected: 2-pentanedioic, octanedioic, phthalic, citric, nonanodioic, 12-methyltetradecanoic, palmitic, oleic, linoleic, stearic, 11,14,17-eicosatrie-noic and 11,14-eicosadienoic. Their identification was based on the times of retention and it was confirmed by comparing the spectra of masses with those of patterns. The presence of these compounds in the fruits of B. pinguin L. is reported for the first time.

  1. Zircon U-Pb and molybdenite Re-Os geochronology and geological significance of the Baoshan porphyry Cu polymetallic deposit in Jiangxi province

    Science.gov (United States)

    Jia, Liqiong; Wang, Liang

    2017-10-01

    Baoshan porphyry Cu polymetallic deposit belongs to Jiujiang-Ruichang Cu-Au ore field, which is a component part of the Middle-Lower Yangtze River Cu-Au metallogenic belt. The U-Pb LA-MC-TCP MS dating of the zircons from Baoshan granodiorite porphyry yields an age of 147.81±0.48Ma (MSWD=1.07). Six molybdenite samples separated from Baoshan deposit are used for Re-Os dating and obtained the weighted average age of 147.42±0.84Ma and an isochron age of 147.7±1.2Ma. These ages suggest that the mineralization in the Baoshan deposit is genetically associated to the granodiorite porphyry, and the process of rock-and ore-forming is continuous. These data indicate that ages of intrusion and ore-body from Baoshan deposit are almost identical to other typical magmatic intrusion and deposits in Jiujiang-Ruichang metallogenic district. Tt is inferred that the Baoshan deposit was formed in the transition from EW-striking Tndosinian tectonic domain to NE-striking Paleo-Pacific tectonic domain.

  2. A internacionalização da GOL Transportes Aéreos: um desafio enfrentado com criatividade estratégica

    Directory of Open Access Journals (Sweden)

    Maurício Emboaba Moreira

    2008-01-01

    Full Text Available This article discusses the internationalization of GOL Transportes Aéreos S/A in South America, identifies viable alternatives at the time (2005, and explores the adaptation of the strategy used, in confrontation with its essential competencies, thus obtaining sustainable competitive advantages, which can explain the success reached in a short period of time. GOL’s international expansion made in the period included Argentina (Buenos Aires, Cordoba and Rosario, Bolivia (Santa Cruz de la Sierra, Paraguay (Asunción and Uruguay (Montevideo. Its success came from the predominance of end line flights, which allow costs calculations to be based only upon variable costs. In these conditions, the company could offer very competitive fares, driven to very price sensitive consumers. In its competitive positioning, its B-737 aircraft fleet has been an essential element, particularly adjusted to the high level of daily utilization. Fundamental elements in the strategic articulation were the company creativity, the broad knowledge of the existing legal instruments, as well as its flexibility, getting adapted to several dominant environmental conditions.

  3. The Centrality of Relationships for Pedagogy: The "Whanaungatanga" Thesis

    Science.gov (United States)

    Bishop, Russell; Ladwig, James; Berryman, Mere

    2014-01-01

    "Te Kotahitanga" is a research and professional development project that seeks to reduce educational disparities between indigenous Maori students and their non-Maori peers in New Zealand secondary schools. While evidence of the impact of the project on teachers' practice and the associated gains made by Maori students has been published…

  4. Solution Grown Se/Te Nanowires: Nucleation, Evolution, and The Role of Triganol Te seeds

    Directory of Open Access Journals (Sweden)

    Shan Xudong

    2009-01-01

    Full Text Available Abstract We have studied the nucleation and growth of Se–Te nanowires (NWs, with different morphologies, grown by a chemical solution process. Through systematic characterization of the Se–Te NW morphology as a function of the Te nanocrystallines (NCs precursor, the relative ratio between Se and Te, and the growth time, a number of significant insights into Se–Te NW growth by chemical solution processes have been developed. Specifically, we have found that: (i the growth of Se–Te NWs can be initiated from either long or short triganol Te nanorods, (ii the frequency of proximal interactions between nanorod tips and the competition between Se and Te at the end of short Te nanorods results in V-shaped structures of Se–Te NWs, the ratio between Se and Te having great effect on the morphology of Se–Te NWs, (iii by using long Te nanorods as seeds, Se–Te NWs with straight morphology were obtained. Many of these findings on Se–Te NW growth can be further generalized and provide very useful information for the rational synthesis of group VI based semiconductor NW compounds.

  5. Electrical properties of MIS devices on CdZnTe/HgCdTe

    Science.gov (United States)

    Lee, Tae-Seok; Jeoung, Y. T.; Kim, Hyun Kyu; Kim, Jae Mook; Song, Jinhan; Ann, S. Y.; Lee, Ji Y.; Kim, Young Hun; Kim, Sun-Ung; Park, Mann-Jang; Lee, S. D.; Suh, Sang-Hee

    1998-10-01

    In this paper, we report the capacitance-voltage (C-V) properties of metal-insulator-semiconductor (MIS) devices on CdTe/HgCdTe by the metalorganic chemical vapor deposition (MOCVD) and CdZnTe/HgCdTe by thermal evaporation. In MOCVD, CdTe layers are directly grown on HgCdTe using the metal organic sources of DMCd and DiPTe. HgCdTe layers are converted to n-type and the carrier concentration, ND is low 1015 cm-3 after Hg-vacancy annealing at 260 degrees Celsius. In thermal evaporation, CdZnTe passivation layers were deposited on HgCdTe surfaces after the surfaces were etched with 0.5 - 2.0% bromine in methanol solution. To investigate the electrical properties of the MIS devices, the C-V measurement is conducted at 80 K and 1 MHz. C-V curve of MIS devices on CdTe/HgCdTe by MOCVD has shown nearly flat band condition and large hysteresis, which is inferred to result from many defects in CdTe layer induced during Hg-vacancy annealing process. A negative flat band voltage (VFB approximately equals -2 V) and a small hysteresis have been observed for MIS devices on CdZnTe/HgCdTe by thermal evaporation. It is inferred that the negative flat band voltage results from residual Te4+ on the surface after etching with bromine in methanol solution.

  6. Partial Pressures of Te2 and Thermodynamic Properties of Ga-Te System

    Science.gov (United States)

    Su, Ching-Hua; Curreri, Peter A. (Technical Monitor)

    2001-01-01

    The partial pressures of Te2 in equilibrium with Ga(1-x)Te(x) samples were measured by optical absorption technique from 450 to 1100 C for compositions, x, between 0.333 and 0.612. To establish the relationship between the partial pressure of Te, and the measured optical absorbance, the calibration runs of a pure Te sample were also conducted to determine the Beer's Law constants. The partial pressures of Te2 in equilibrium with the GaTe(s) and Ga2Te3(s)compounds, or the so-called three-phase curves, were established. These partial pressure data imply the existence of the Ga3Te4(s) compound. From the partial pressures of Te2 over the Ga-Te melts, partial molar enthalpy and entropy of mixing for Te were derived and they agree reasonable well with the published data. The activities of Te in the Ga-Te melts were also derived from the measured partial pressures of Te2. These data agree well with most of the previous results. The possible reason for the high activity of Te measured for x less than 0.60 is discussed.

  7. Social disparities in the prevalence of diabetes in Australia and in the development of end stage renal disease due to diabetes for Aboriginal and Torres Strait Islanders in Australia and Maori and Pacific Islanders in New Zealand

    Directory of Open Access Journals (Sweden)

    Kathleen Hill

    2017-10-01

    Full Text Available Abstract Background Disparities in health status occur between people with differing socioeconomic status and disadvantaged groups usually have the highest risk exposure and the worst health outcome. We sought to examine the social disparities in the population prevalence of diabetes and in the development of treated end stage renal disease due to type 1 diabetes which has not previously been studied in Australia and New Zealand in isolation from type 2 diabetes. Methods This observational study examined the population prevalence of diabetes in a sample of the Australian population (7,434,492 using data from the National Diabetes Services Scheme and of treated end stage renal disease due to diabetes using data from the Australian and New Zealand Dialysis and Transplant Registry. The data were then correlated with the Australian Bureau of Statistics Socioeconomic Indexes for Areas for an examination of socioeconomic disparities. Results There is a social gradient in the prevalence of diabetes in Australia with disease incidence decreasing incrementally with increasing affluence (Spearman’s rho = .765 p < 0.001. There is a higher risk of developing end stage renal disease due to type 1 diabetes for males with low socioeconomic status (RR 1.20; CI 1.002–1.459 in comparison to females with low socioeconomic status. In Australia and New Zealand Aboriginal and Torres Strait Islanders, Maori and Pacific Islanders appear to have a low risk of end stage renal disease due to type 1 diabetes but continue to carry a vastly disproportionate burden of end stage renal disease due to type 2 diabetes (RR 6.57 CI 6.04–7.14 & 6.48 CI 6.02–6.97 respectively p < 0.001 in comparison to other Australian and New Zealanders. Conclusion Whilst low socioeconomic status is associated with a higher prevalence of diabetes the inverse social gradient seen in this study has not previously been reported. The social disparity seen in relation to treated end stage

  8. Social disparities in the prevalence of diabetes in Australia and in the development of end stage renal disease due to diabetes for Aboriginal and Torres Strait Islanders in Australia and Maori and Pacific Islanders in New Zealand.

    Science.gov (United States)

    Hill, Kathleen; Ward, Paul; Grace, Blair S; Gleadle, Jonathan

    2017-10-11

    Disparities in health status occur between people with differing socioeconomic status and disadvantaged groups usually have the highest risk exposure and the worst health outcome. We sought to examine the social disparities in the population prevalence of diabetes and in the development of treated end stage renal disease due to type 1 diabetes which has not previously been studied in Australia and New Zealand in isolation from type 2 diabetes. This observational study examined the population prevalence of diabetes in a sample of the Australian population (7,434,492) using data from the National Diabetes Services Scheme and of treated end stage renal disease due to diabetes using data from the Australian and New Zealand Dialysis and Transplant Registry. The data were then correlated with the Australian Bureau of Statistics Socioeconomic Indexes for Areas for an examination of socioeconomic disparities. There is a social gradient in the prevalence of diabetes in Australia with disease incidence decreasing incrementally with increasing affluence (Spearman's rho = .765 p < 0.001). There is a higher risk of developing end stage renal disease due to type 1 diabetes for males with low socioeconomic status (RR 1.20; CI 1.002-1.459) in comparison to females with low socioeconomic status. In Australia and New Zealand Aboriginal and Torres Strait Islanders, Maori and Pacific Islanders appear to have a low risk of end stage renal disease due to type 1 diabetes but continue to carry a vastly disproportionate burden of end stage renal disease due to type 2 diabetes (RR 6.57 CI 6.04-7.14 & 6.48 CI 6.02-6.97 respectively p < 0.001) in comparison to other Australian and New Zealanders. Whilst low socioeconomic status is associated with a higher prevalence of diabetes the inverse social gradient seen in this study has not previously been reported. The social disparity seen in relation to treated end stage renal disease due to type 2 diabetes for Aboriginal and Torres Strait

  9. Thermochemical properties of silver tellurides including empressite (AgTe) and phase diagrams for Ag-Te and Ag-Te-O

    Science.gov (United States)

    Voronin, Mikhail V.; Osadchii, Evgeniy G.; Brichkina, Ekaterina A.

    2017-10-01

    This study compiles original experimental and literature data on the thermodynamic properties (ΔfG°, S°, ΔfH°) of silver tellurides (α-Ag2Te, β-Ag2Te, Ag1.9Te, Ag5Te3, AgTe) obtained by the method of solid-state galvanic cell with the RbAg4I5 and AgI solid electrolytes. The thermodynamic data for empressite (AgTe, pure fraction from Empress Josephine Mine, Colorado USA) have been obtained for the first time by the electrochemical experiment with the virtual reaction Ag + Te = AgTe. The Ag-Te phase diagrams in the T - x and log fTe2 (gas) - 1/ T coordinates have been refined, and the ternary Ag-Te-O diagrams with Ag-Te-TeO2 (paratellurite) composition range have been calculated.

  10. n-(CdMgTe/CdTe)/(p-(CdTe/ZnCdTe/ZnTe)/p-GaAs heterostructure diode for photosensor applications

    Science.gov (United States)

    Yahia, I. S.; AlFaify, S.; Abutalib, M. M.; Chusnutdinow, S.; Wojtowicz, T.; Karczewski, G.; Yakuphanoglu, F.; Al-Bassam, A.; El-Naggar, A. M.; El-Bashir, S. M.

    2016-05-01

    High quality n-(CdMgTe:I/n-CdTe:I)/(p-CdTe:N/p-ZnCdTe:N/p-ZnTe:N)/p-GaAs heterojunction diodes have been fabricated by molecular beam epitaxial growth. The illumination effect on the complex impedance and conductivity of heterostructure diode was investigated. The illumination intensities were taken up to the 200 mW/cm2 with frequency range of 42 Hz to 1 MHz. The observed real and imaginary parts of the complex impedance were strongly dependent on the illumination frequency. The inverse relation was observed between the illumination intensity and the complex impedance. The relaxation mechanism of the diode was analyzed by the Cole-Cole plots. The radius of the Cole-Cole curve decreases with increasing illumination intensity. This suggests a mechanism of illumination dependent on the relaxation process. It is also found that the conductivity increases linearly with increasing the illumination intensity. We can conclude that the new design heterostructure diode in our work is a good candidate in photodetector and optoelectronic applications.

  11. Shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses using WinXCom and MCNP5 code

    Science.gov (United States)

    Dong, M. G.; El-Mallawany, R.; Sayyed, M. I.; Tekin, H. O.

    2017-12-01

    Gamma ray shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses, where AnOm is Nb2O5 = 0.01, 5, Nd2O3 = 3, 5 and Er2O3 = 5 mol% have been achieved. Shielding parameters; mass attenuation coefficients, half value layers, and macroscopic effective removal cross section for fast neutrons have been computed by using WinXCom program and MCNP5 Monte Carlo code. In addition, by using Geometric Progression method (G-P), exposure buildup factor values were also calculated. Variations of shielding parameters are discussed for the effect of REO addition into the glasses and photon energy.

  12. TE Wave Measurement and Modeling

    CERN Document Server

    Sikora, John P; Sonnad, Kiran G; Alesini, David; De Santis, Stefano

    2013-01-01

    In the TE wave method, microwaves are coupled into the beam-pipe and the effect of the electron cloud on these microwaves is measured. An electron cloud (EC) density can then be calculated from this measurement. There are two analysis methods currently in use. The first treats the microwaves as being transmitted from one point to another in the accelerator. The second more recent method, treats the beam-pipe as a resonant cavity. This paper will summarize the reasons for adopting the resonant TE wave analysis as well as give examples from CESRTA and DA{\\Phi}NE of resonant beam-pipe. The results of bead-pull bench measurements will show some possible standing wave patterns, including a cutoff mode (evanescent) where the field decreases exponentially with distance from the drive point. We will outline other recent developments in the TE wave method including VORPAL simulations of microwave resonances, as well as the simulation of transmission in the presence of both an electron cloud and magnetic fields.

  13. Highest-order optical phonon-mediated relaxation in CdTe/ZnTe quantum dots

    International Nuclear Information System (INIS)

    Masumoto, Yasuaki; Nomura, Mitsuhiro; Okuno, Tsuyoshi; Terai, Yoshikazu; Kuroda, Shinji; Takita, K.

    2003-01-01

    The highest 19th-order longitudinal optical (LO) phonon-mediated relaxation was observed in photoluminescence excitation spectra of CdTe self-assembled quantum dots grown in ZnTe. Hot excitons photoexcited highly in the ZnTe barrier layer are relaxed into the wetting-layer state by emitting multiple LO phonons of the barrier layer successively. Below the wetting-layer state, the LO phonons involved in the relaxation are transformed to those of interfacial Zn x Cd 1-x Te surrounding CdTe quantum dots. The ZnTe-like and CdTe-like LO phonons of Zn x Cd 1-x Te and lastly acoustic phonons are emitted in the relaxation into the CdTe dots. The observed main relaxation is the fast relaxation directly into CdTe quantum dots and is not the relaxation through either the wetting-layer quantum well or the band bottom of the ZnTe barrier layer. This observation shows very efficient optical phonon-mediated relaxation of hot excitons excited highly in the ZnTe conduction band through not only the ZnTe extended state but also localized state in the CdTe quantum dots reflecting strong exciton-LO phonon interaction of telluride compounds

  14. Piezoelectric effect in CdTe/CdMnTe and CdTe/CdZnTe quantum wells

    International Nuclear Information System (INIS)

    Andre, Regis

    1994-01-01

    Materials with zinc-blende type structure are piezoelectric: any strain along a polar axis generates an electrical polarisation. Strained quantum wells of cubic II-VI or III-V semiconductors, grown along [111] or [112] axis, exhibit a strong built-in piezo-electric field (100 kV/cm for 1% strains). Such structures are very promising for applications to optical modulation, but it is necessary to study first the physical properties of piezoelectric heterostructures before they can be used in optical devices. For this purpose, we have performed an optical study of strained CdTe/CdMnTe or CdTe/CdZnTe quantum wells coherently grown by molecular beam epitaxy on [111] or [112] oriented substrates. Effects of piezoelectric field on optical and electronic properties of quantum wells have been analyzed in terms of the envelop function model, taking into account the effects of biaxial strains for [hhk] growth axis. Moreover, we have proposed an original way of measuring piezoelectric field in strained quantum wells, and we have used this method to show that CdTe exhibits strong non-linearities for piezoelectric field versus strain. This effect has never been mentioned before. We have also performed measurements of the piezoelectric coefficient e14 under high hydrostatic pressure inducing strains up to 2%, which shows that part of the non-linear effect is a volume effect. We have also studied the effects of the piezoelectric field on excitons in quantum wells. The binding energy decreases slightly when the electric field increases, but the oscillator strength, for the fundamental transition, decreases dramatically with the overlap of the envelope wavefunctions of electrons and holes. We have performed a modelization of an exciton in a piezoelectric quantum well using two variational parameters. This model provides an accurate calculation of excitonic absorption. Our experimental and theoretical results are in very good agreement, without any fitting parameters, for a large

  15. Partial enthalpies of Bi and Te in Bi-Te melts and of In and Te in In-Te melts

    International Nuclear Information System (INIS)

    Yassin, Abeer; Amzil, Abdelhamid; Castanet, Robert

    2000-01-01

    Full text.Calorimetric measurement are reported which allow the enthalpic behaviour of Bi-Te melts to be established. Further work is required, however, to supplement results obtained for In-Te melts. The partial enthalpies of bismuth and tellurium in the Bi-Te melts at 755K and those of indium and tellurium in the In-Te melts at 1010 and 987K were measured at high dilution by direct reaction calorimetry (drop method) with the help of a Tian-Calvet calorimeter. The limiting partial enthalpies of the components were deduced by extrapolation at infinite dilution: Δh f,∞ B i(755K)/KJ.mol -1 = -34.0 and Δh f,∞ Te(755K) /KJ·mol -1 = -24.1 in the Bi-Te melts Δh f,∞ In(1010K) /KJ·mol -1 = -75.9 and Δh f,∞ Te(1010K) /KJ·mol -1 = -47.8 in the In-Te melts Δh f,∞ In(987K) /KJ·mol -1 = -75.2 and Δh f,∞ Te(987K) /KJ·mol -1 = -48.0 in the In-Te melts

  16. A computational study of the addition of ReO3L (L = Cl(-), CH3, OCH3 and Cp) to ethenone.

    Science.gov (United States)

    Aniagyei, Albert; Tia, Richard; Adei, Evans

    2016-01-01

    The periselectivity and chemoselectivity of the addition of transition metal oxides of the type ReO3L (L = Cl, CH3, OCH3 and Cp) to ethenone have been explored at the MO6 and B3LYP/LACVP* levels of theory. The activation barriers and reaction energies for the stepwise and concerted addition pathways involving multiple spin states have been computed. In the reaction of ReO3L (L = Cl(-), OCH3, CH3 and Cp) with ethenone, the concerted [2 + 2] addition of the metal oxide across the C=C and C=O double bond to form either metalla-2-oxetane-3-one or metalla-2,4-dioxolane is the most kinetically favored over the formation of metalla-2,5-dioxolane-3-one from the direct [3 + 2] addition pathway. The trends in activation and reaction energies for the formation of metalla-2-oxetane-3-one and metalla-2,4-dioxolane are Cp Cp Cp Cp Cp. The direct [2 + 2] addition pathways leading to the formations of metalla-2-oxetane-3-one and metalla-2,4-dioxolane is thermodynamically the most favored for the ligands L = OCH3 and Cl(-). The difference between the calculated [2 + 2] activation barriers for the addition of the metal oxide LReO3 across the C=C and C=O functionalities of ethenone are small except for the case of L = Cl(-) and OCH3. The rearrangement of the metalla-2-oxetane-3-one-metalla-2,5-dioxolane-3-one even though feasible, are unfavorable due to high activation energies of their rate-determining steps. For the rearrangement of the metalla-2-oxetane-3-one to metalla-2,5-dioxolane-3-one, the trends in activation barriers is found to follow the order OCH3 Cp. The trends in the activation energies for the most favorable [2 + 2] addition pathways for the LReO3-ethenone system is CH3 > CH3O(-) > Cl(-) > Cp. For the analogous ethylene-LReO3 system, the trends in activation and reaction energies for the most favorable [3 + 2] addition pathway is CH3 > CH3O(-) > Cl(-) > Cp [10]. Even though the most favored pathway in the ethylene-LReO3 system is

  17. A Estratégia de Overbooking e sua Aplicação no Mercado de Transporte Aéreo Brasileiro

    Directory of Open Access Journals (Sweden)

    Alessandro Vinícius Marques de Oliveira

    2010-06-01

    Full Text Available

    Resumo Uma questão fundamental relativa à gestão de empresas aéreas diz respeito ao adequado balanceamento entre oferta e demanda. Grande parte dos vôos das companhias aéreas decola com um número significativo de assentos vazios, sendo uma parcela significativa dessa capacidade ociosa gerada pelos chamados passageiros no-show e pelos cancelamentos de reserva feitos com pouca antecedência em relação ao horário do vôo. No Brasil, o hábito de cancelar a reserva não é comum entre os usuários do transporte aéreo; na maioria das vezes, os passageiros esperam que o prazo da reserva expire ou, quando o bilhete já foi adquirido, simplesmente não comparecem ao embarque. Estas práticas, consentidas pelas empresas aéreas devido à flexibilidade oferecida em determinados bilhetes de passagem (classes tarifárias, inviabilizam a reutilização dos assentos que foram “desocupados” em tempo hábil para o vôo. Desta forma, torna-se economicamente racional que as empresas procurem se proteger das perdas resultantes adotando mecanismos como o aumento virtual da capacidade de uma aeronave, ou overbooking. O presente trabalho tem como objetivo realizar uma análise de eficiência e de riscos com relação à prática de overbooking, ou seja, verificar a viabilidade econômica e os riscos associados de se praticar tal estratégia, apontando suas vantagens e desvantagens, riscos associados e questões referentes às responsabilidades e à legislação.

    Palavras-chave: overbooking; gerenciamento de receitas; reservas; transporte aéreo.

    Abstract

    A key issue regarding airline management is related to the balance between demand and supply. It is a common situation to observe flights departing with a significant amount of empty seats, mainly due to no-show passengers and the very late canceling of reservations. In Brazil, airline passengers do not usually cancel reservations; on the contrary, they usually wait for the

  18. Origin of the volcanic-hosted Yamansu Fe deposit, Eastern Tianshan, NW China: constraints from pyrite Re-Os isotopes, stable isotopes, and in situ magnetite trace elements

    Science.gov (United States)

    Huang, Xiao-Wen; Zhou, Mei-Fu; Beaudoin, Georges; Gao, Jian-Feng; Qi, Liang; Lyu, Chuan

    2018-01-01

    The Yamansu Fe deposit (32 Mt at 51% Fe) in the Eastern Tianshan Orogenic Belt of NW China is hosted in early Carboniferous volcano-sedimentary rocks and spatially associated with skarn. The paragenetic sequence includes garnet-diopside (I), magnetite (II), hydrous silicate-sulfide (III), and calcite-quartz (IV) stages. Pyrite associated with magnetite has a Re-Os isochron age of 322 ± 7 Ma, which represents the timing of pyrite and, by inference, magnetite mineralization. Pyrite has δ 34SVCDT values of - 2.2 to + 2.9‰, yielding δ 34SH2S values of - 3.1 to 2‰, indicating the derivation of sulfur from a magmatic source. Calcite from stages II and IV has δ 13CVPDB values from - 2.5 to - 1.2‰, and - 1.1 to 1.1‰, and δ 18OVSMOW values from 11.8 to 12.0‰ and - 7.7 to - 5.2‰, respectively. Calculated δ 13C values of fluid CO2 and water δ 18O values indicate that stage II hydrothermal fluids were derived from magmatic rocks and that meteoric water mixed with the hydrothermal fluids in stage IV. Some ores contain magnetite with obvious chemical zoning composed of dark and light domains in BSE images. Dark domains have higher Mg, Al, Ca, Mn, and Ti but lower Fe and Cr contents than light domains. The chemical zoning resulted from a fluctuating fluid composition and/or physicochemical conditions (oscillatory zoning), or dissolution-precipitation (irregular zoning) via infiltration of magmatic-hydrothermal fluids diluted by late meteoric water. Iron was mainly derived from fluids similar to that in skarn deposits.

  19. EFECTO DE DOS NIVELES DE FORRAJE ARBÓREO TEPOZÁN (Buddleia cordata EN EL COMPORTAMIENTO PRODUCTIVO Y MICROBIOLÓGICO RUMINAL EN CABRAS

    Directory of Open Access Journals (Sweden)

    Marcos Perez-Sato

    2010-10-01

    Full Text Available Se evaluó el efecto de la inclusión (0, 15 y 30 % de forraje arbóreo de Buddleida cordata (Tepozán en el comportamiento productivo y los microorganismos del rumen en cabras. Se distribuyeron al azar 30 cabras criollas con un peso vivo promedio de 14 kg en tres tratamientos y fueron alojadas en corrales individuales durante 45 días. Se midió ganancia diaria de peso (GDP, consumo de materia seca (CMS, pH ruminal, concentración de bacterias totales, celulolíticas y protozoarios a los, 30 y 45 días del periodo experimental. El diseño experimental fue completamente al azar con mediciones repetidas a través del tiempo, analizando los datos de GDP, CMS y pH ruminal con PROC MIXED. El número de bacterias fue estadísticamente analizado por intervalos de confianza. No hubo diferencias entre tratamientos (p>0.05 por la inclusión de B. cordata en la dieta sobre la GDP, CMS, pH ruminal, concentración de bacterias totales, celulolíticas y protozoarios. No se presentaron diferencia entre periodos (p>0.05 en ninguna variable. Se concluye  que el henificado de B. cordata muestra potencial para ser incluido en la dieta de cabras hasta un máximo de 30%, sin afectar negativamente las variables productivas ni a los microorganismos del rumen. Â

  20. MODELOS MATEMÁTICOS PARA LA ESTIMACIÓN DE BIOMASA DE ÓRGANOS AÉREOS DE LIMÓN 'PERSA' (Citrus latifolia Tan.

    Directory of Open Access Journals (Sweden)

    L. A. Crespo-Herrera

    2007-01-01

    Full Text Available En muchos de los estudios de crecimiento de las plantas se requiere evaluar la biomasa, lo cual normalmente implica la destrucción de los árboles. En el presente trabajo se generaron modelos matemáticos de alta confiabilidad que estiman la cantidad de biomasa de órganos aéreos de limón 'Persa' con base en otras variables que no requieren la destrucción del material vegetal y además son de fácil medición. Para ello, se separaron ramas, hojas y frutos de los árboles y se les midió la cantidad de biomasa además del área foliar de las hojas y otras características morfológicas inherentes a cada tipo de órgano. Se encontró que la cantidad de biomasa de cada órgano se encuentra estrechamente relacionada con las siguientes características: para las ramas, el volumen calculado por las fórmulas del cono y cono truncado, en los casos de las ramas no podadas y podadas, respectivamente; para los frutos, el diámetro ecuatorial, y para las hojas, la longitud de la lámina y su ancho máximo. Se generaron modelos para cada órgano con coeficientes de determinación muy elevados (entre 0.9528 y 0.9981 y C(p aceptable (entre 1.6696 y 16.3685, para modelos de 2 a 4 variables.

  1. Soluciones cristaloides y coloides, como sustitutas de la sangre en el cebado del circuito extracorpóreo durante la cirugía cardiovascular

    Directory of Open Access Journals (Sweden)

    José R Llanes Echevarría

    2002-04-01

    Full Text Available Se realizó un estudio cualitativo donde se exponen las características principales, objetivos de aplicación y las ventajas que ofrecen las diferentes soluciones coloidales y electrolíticas utilizadas en el cebado del circuito extracorpóreo. Como objetivo principal se exponen los argumentos necesarios que permiten al perfusionista combinar determinadas soluciones, para conservar la osmolaridad, la presión oncótica del plasma, mejorar el flujo microcirculatorio y evitar las transfusiones de sangre y hemoderivados innecesarias. También se mencionan diferentes técnicas para conservar el nivel del hematócrito, como son el uso de hemofiltros, concentrador de células y la aplicación de la cardioplejia sanguínea, que aunque su principal objetivo es la protección miocárdica, también sustituye los grandes volúmenes de líquido que caracteriza el uso de la cardioplejia cristaloideThe chief characteristics, objectives of application and the advantages the colloidal and electrolytic solutions used in the priming of the extracorporeal circuit offer are explained in this qualitative study. The necessary arguments that allow the perfusionist to combine certain solutions to conserve osmolarity, the oncotic pressure of plasma, to improve the microcirculatory flow and to avoid blood transfusions and unnecessary hemoderivatives, are dealt with as the fundamental aim. Reference is made to different techniques used to conserve the haematocrit level, such as: the use of haemofilters, cell concentrator and the application of blood cardioplegia, whose main goal is the myocardial protection, but it also substitutes the great volumes of fluid that characterize the use of crystalloid cardioplegia

  2. A subduction wedge origin for Paleoarchean peridotitic diamonds and harzburgites from the Panda kimberlite, Slave craton: evidence from Re-Os isotope systematics

    Science.gov (United States)

    Westerlund, K. J.; Shirey, S. B.; Richardson, S. H.; Carlson, R. W.; Gurney, J. J.; Harris, J. W.

    2006-09-01

    An extensive study of peridotitic sulfide inclusion bearing diamonds and their prospective harzburgitic host rocks from the 53 Ma Panda kimberlite pipe, Ekati Mine, NWT Canada, has been undertaken with the Re-Os system to establish their age and petrogenesis. Diamonds with peridotitic sulfide inclusions have poorly aggregated nitrogen (bearing diamonds and indicates residence in the cooler portion of the Slave craton lithospheric mantle. For most of the sulfide inclusions, relatively low Re contents (average 0.457 ppm) and high Os contents (average 339 ppm) lead to extremely low 187Re/188Os, typically << 0.05. An age of 3.52 ± 0.17 Ga (MSWD = 0.46) and a precise initial 187Os/188Os of 0.1093 ± 0.0001 are given by a single regression of 11 inclusions from five diamonds that individually provide coincident internal isochrons. This initial Os isotopic composition is 6% enriched in 187Os over 3.5 Ga chondritic or primitive mantle. Sulfide inclusions with less radiogenic initial Os isotopic compositions reflect isotopic heterogeneity in diamond forming fluids. The harzburgites have even lower initial 187Os/188Os than the sulfide inclusions, some approaching the isotopic composition of 3.5 Ga chondritic mantle. In several cases isotopically distinct sulfides occur in different growth zones of the same diamond. This supports a model where C-O-H-S fluids carrying a radiogenic Os signature were introduced into depleted harzburgite and produced diamonds containing sulfides conforming to the 3.5 Ga isochron. Reaction of this fluid with harzburgite led to diamonds with less radiogenic inclusions while elevating the Os isotope ratios of some harzburgites. Subduction is a viable way of introducing such fluids. This implies a role for subduction in creating early continental nuclei at 3.5 Ga and generating peridotitic diamonds.

  3. promisorios de Myrciaria dubia (H.B.K. “camu camu” para propagación vegetativa por acodo aéreo

    Directory of Open Access Journals (Sweden)

    Jiang Oliver Liao Torres

    2012-01-01

    Full Text Available El objetivo del presente trabajo fue evaluar el efecto de la ubicación y diámetro de la rama en tres genotipospromisorios de camu camu utilizando la técnica del acodo aéreo sobre el enraizamiento y brotación. Lasplantas madres fueron acodadas, posteriormente las ramas enraizadas se trasplantaron siguiendo el diseño deBloques Completos al Azar, con tres repeticiones. A los 3 meses del trasplante se realizó la evaluación de lasvariables, encontrando los mejores promedios para el Número de raíces al Tercio medio, Diámetro grueso,Genotipo MD-015 y al Tercio superior, Diámetro grueso, Genotipo MD-015 con 28.67 y 28.33 raíces,respectivamente; en la variable Longitud de raíces el Tercio superior, Diámetro grueso, Genotipo MD-015mostró los mejores resultados con 15.27 cm. Con respecto al Número de brotes el Tercio Superior, DiámetroGrueso, Genotipo MD-014 y el Tercio superior, Diámetro grueso, Genotipo MD-015 alcanzaron los mejoresresultados con 13.00 y 12.67 brotes, respectivamente; en la Longitud de brotes, el mejor tratamiento fue elTercio superior, Diámetro grueso, Genotipo MD-015 con 30.73 cm; finalmente en la variable Número dehojas/brote sobresalieron el Tercio superior, Diámetro grueso, Genotipo MD-014 y Tercio superior, Diámetrogrueso, Genotipo MD-015 con 15.10 y 14.83 hojas por brote, respectivamente. Los resultados permitieronidentificar al Tercio superior, Diámetro grueso, Genotipo MD-015 como los mejores en cuanto a la capacidadde enraizamiento y brotación.

  4. Surface passivation for CdTe devices

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Matthew O.; Perkins, Craig L.; Burst, James M.; Gessert, Timothy A.; Barnes, Teresa M.; Metzger, Wyatt K.

    2017-08-01

    In one embodiment, a method for surface passivation for CdTe devices is provided. The method includes adjusting a stoichiometry of a surface of a CdTe material layer such that the surface becomes at least one of stoichiometric or Cd-rich; and reconstructing a crystalline lattice at the surface of the CdTe material layer by annealing the adjusted surface.

  5. Superconducting transition in TlBiTe/sub 2/ and TlTe compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kantser, V G; Popovich, N S; Sidorenko, A S

    1985-10-01

    On the basis of zone structure calculation for TlBiTe/sub 2/ and TlTe it is found that TlBiTe/sub 2/ is a narrow-gap semiconductor and TlTe is a p-metal. At Tsub(c)=0.19 K TlTe is found to experience the superconducting transition. In TlBiTe/sub 2/ superconductivity is not observed to occur up to 0.05 K, since there is a possibility of occupying the high density of states zones because they are remote from actual ones. The earlier discovered superconducting transition in TlBiTe/sub 2/ is inherent in the alien phase of TlTe.

  6. On the mean square displacements (MSD) of Hg and Te in HgTe

    International Nuclear Information System (INIS)

    Madhavan, Y.; Ramachandran, K.

    1989-01-01

    The mean square displacements (MSD) of Hg and Te in the perfect system of HgTe are worked out in the modified rigid ion model of Plumelle and Vandevyver. Also the MSD of Hg and Te neighbours around anion and cation vacancies in HgTe are worked out giving an active role for the vacancy following the theory of Maradudin et al. The results are compared with experimental values. (author)

  7. Diseño e implementación de un sistema de control de vuelo para un vehículo aéreo no tripulado tipo cuadricóptero

    Directory of Open Access Journals (Sweden)

    Brian Mauricio Lara Sosa

    2017-07-01

    Full Text Available Contexto: La industria aeroespacial ha tenido bastante auge y así mismo el desarrollo y aplicación a los sistemas autónomos, propiciando desarrollos importantes en su implementación, y sistemas de control. Método: En este trabajo se presenta el desarrollo y la implementación de un vehículo aéreo no tripulado, tipo quadricóptero, se inicia con el análisis matemático de los sistemas de vehículos aéreos encontrando el modelo dinámico; el modelado del prototipo se basa en las ecuaciones Euler LaGrange. Posteriormente, se realiza el diseño de la estructura y el desarrollo de los sistemas de control basado en modos deslizantes; se aplica la ley de control basada en modos deslizantes en el sistema implementado que utiliza solamente información de pitch, roll y elevación. Resultados: Se implementó un prototipo de vehículo aéreo no tripulado tipo quadricóptero, y se implementó el sistema de control, donde se obtuvo un adecuado seguimiento de la referencia. Conclusiones: La adecuada selección de los elementos para la implementación del prototipo permite poder implementar diferentes estrategias de control, para este caso demostrando el adecuado trabajo de los modos deslizantes para la estabilización en dos ejes del quadricóptero.

  8. In situ study on the formation of FeTe

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Wulff, Anders Christian; Yue, Zhao

    2011-01-01

    The formation of the FeTe compound from a mixture of Fe and Te powders was studied in situ by means of high-energy synchrotron X-ray diffraction. FeTe does not form directly from the starting elements; instead, FeTe2 forms as an intermediate product. During a 2 °C/min heating ramp, Te first reacts...

  9. Designing Diameter-Modulated Heterostructure Nanowires of PbTe/Te by Controlled Dewetting.

    Science.gov (United States)

    Kumar, Abinash; Kundu, Subhajit; Samantaray, Debadarshini; Kundu, Paromita; Zanaga, Daniele; Bals, Sara; Ravishankar, N

    2017-12-13

    Heterostructures consisting of semiconductors with controlled morphology and interfaces find applications in many fields. A range of axial, radial, and diameter-modulated nanostructures have been synthesized primarily using vapor phase methods. Here, we present a simple wet chemical routine to synthesize heterostructures of PbTe/Te using Te nanowires as templates. A morphology evolution study for the formation of these heterostructures has been performed. On the basis of these control experiments, a pathway for the formation of these nanostructures is proposed. Reduction of a Pb precursor to Pb on Te nanowire templates followed by interdiffusion of Pb/Te leads to the formation of a thin shell of PbTe on the Te wires. Controlled dewetting of the thin shell leads to the formation of cube-shaped PbTe that is periodically arranged on the Te wires. Using control experiments, we show that different reactions parameters like rate of addition of the reducing agent, concentration of Pb precursor and thickness of initial Te nanowire play a critical role in controlling the spacing between the PbTe cubes on the Te wires. Using simple surface energy arguments, we propose a mechanism for the formation of the hybrid. The principles presented are general and can be exploited for the synthesis of other nanoscale heterostructures.

  10. Bacon, Lettuce and Tomato: een strategie om leerlingen te helpen hun antwoorden op examenvragen te verbeteren

    NARCIS (Netherlands)

    Kneppers, L.

    2014-01-01

    In Tutor2u las ik dat in een workshop een strategie was besproken om leerlingen te helpen hun examenantwoorden vollediger en juister te formuleren. De strategie heet in Groot Brittannië BLT, voor leerlingen daar gemakkelijk te onthouden vanwege de populaire Bacon, Lettuce en Tomato sandwich.

  11. Mulheres com síndrome dos ovários policísticos apresentam maior frequência de síndrome metabólica independentemente do índice de massa corpóreo

    OpenAIRE

    Melo,Anderson Sanches; Macedo,Carolina Sales Vieira; Romano,Lucas Gabriel Maltoni; Ferriani,Rui Alberto; Navarro,Paula Andrea de Albuquerque Salles

    2012-01-01

    OBJETIVO: Avaliar a prevalência de síndrome metabólica e dos seus critérios definidores em mulheres com síndrome dos ovários policísticos do Sudeste brasileiro, estratificadas de acordo com o índice de massa corpóreo e comparadas com controles ovulatórias. MÉTODOS: Estudo transversal, realizado com 332 mulheres em idade reprodutiva, que foram divididas em dois grupo: Controle, constituído por 186 mulheres com ciclos menstruais regulares, sintomas ovulatórios e sem diagnóstico de síndrome dos ...

  12. Re-Os, Sm-Nd, U-Pb, and stepwise lead leaching isotope systematics in shear-zone hosted gold mineralization: genetic tracing and age constraints of crustal hydrothermal activity

    Science.gov (United States)

    Frei, R.; Nägler, Th. F.; Schönberg, R.; Kramers, J. D.

    1998-06-01

    A combined Re-Os, Sm-Nd, U-Pb, and stepwise Pb leaching (PbSL) isotope study of hydrothermal (Mo-W)-bearing minerals and base metal sulfides from two adjacent shear zone hosted gold deposits (RAN, Kimberley) in the Harare-Shamva greenstone belt (Zimbabwe) constrain the timing of the mineralizing events to two periods. During an initial Late Archean event (2.60 Ga) a first molybdenite-scheelite bearing paragenesis was deposited in both shear zone systems, followed by a local reactivation of the shear systems during an Early Proterozoic (1.96 Ga) tectono-thermal overprint, during which base metal sulfides and most of the gold was (re-)deposited. While PbSL has revealed an open-system behavior of the U-Pb systematics in molybdenite and wolframite from the RAN mine, initial Archean Re-Os ages are still preserved implying that this system in these minerals was more resistant to the overprint. A similar retentivity could be shown for the Sm-Nd system in scheelite and powellite associated with the above ore minerals. Re-Os isotopic data from the Proterozoic mineralization in the Kimberley mine point to a recent gain of Re, most pronouncedly affecting Fe-rich sulfides such as pyrrhotite. A significant Re-loss in powellitic scheelite (an alteration phase of molybdenite-bearing scheelite), coupled with a marked loss of U in W-Mo ore minerals, complements the observation of a major Re uptake in Fe-sulfides during oxidizing conditions in a weathering environment. Pyrrhotite under these conditions behaves as an efficient Re-sink. Lead isotope signatures from PbSL residues of molybdenite, powellite, and quartz indicate a continental crustal source and/or contamination for the mineralizing fluid by interaction of the fluids with older sedimentary material as represented by the direct host country rocks. Our investigation reveals the potential of the Re-Os isotopic system applied to crustal hydrothermal ore minerals for genetic tracing and dating purposes. The simplified chemical

  13. Vehículos aéreos no tripulados - UAV para la elaboración de cartografías escalas grandes referidas al marco de referencia SIRGAS-ECUADOR

    OpenAIRE

    Sani, Juan Carlos; Tierra, Alfonso; Robayo, Alexander

    2015-01-01

    Resumen. - El avance acelerado de las tecnologías Geoespaciales en la actualidad, permiten desarrollar aplicaciones cada vez más precisas y con un costo menor, que al utilizar metodologías tradicionales. Por ejemplo, el avance de los UAS (Sistemas Aéreos No Tripulados) equipados con cámaras que poseen sensores más sensibles capaces de capturar escenas en formato digital de igual calidad que cámaras fotogramétricas, alcanzando precisiones sub métricas de forma más asequible. El objetivo de est...

  14. Re-Os dating on pyrite and metal sources tracing in porphyry-type and neutral epithermal deposits: example of the Bolcana, Troita and Magura deposits, Apuseni Mountains, Romania

    International Nuclear Information System (INIS)

    Cardon, Olivier

    2007-01-01

    Many porphyry-type (Cu-Au) and neutral epithermal (Pb-Zn and Au ± Ag) ore deposits are encountered in the region of the Apuseni Mountains, located at the foot of the Carpathian chain in the Western Romania. These deposits are related to a Neogene andesitic volcanism. In order to demonstrate possible genetic relationships between the porphyry-type and neutral epithermal deposits, the Bolcana porphyry has been investigated since it is surrounded by a number of epithermal low-sulfidation veins with a Pb-Zn ± Au mineralisation. These veins are currently mined at the Troita and Magura sites. A structural analysis and a 3D modelling pf these deposits indicate that the geometry and orientation of fractures and mineralized vein are consistent both with direction of regional extension and with a NW-SE progression of the different andesitic intrusions. In order to establish precisely the temporal relationship between the different ore deposits, a Re-Os dating method has been developed and applied on pyrite which is ubiquitous in all of the deposits. This method enabled us to assign an age of 10.9 ± 1.9 Ma for the porphyry-hosted mineralization. The ages obtained for the epithermal systems are somewhat approximative as perturbations of the Re-Os system are observed for these environments. A fractionation of rhenium responsible for a significant enrichment in this element for the apical zone of the porphyry has been demonstrated. This enrichment is most probably related to a maximum boiling event, which may also explain a similar enrichment in arsenic for the pyrite in the same zone. The sources for the metals have been characterized at the district scale by combining two isotopic systems (Re-Os and Pb-Pb) on both pyrite and galena. The osmium data indicate that the Troita deposit has composition which is similar to that of the Bolcana porphyry. In contrast the results obtained for the Magura deposits indicate the Re-OS system has in this case been perturbed due to a

  15. Diseño de un transportador aéreo capacidad 500 kg altura 300 metros, para la Central Hidroeléctrica Ing. Carlos Mora Carrión de la Provincia de Zamora Chinchipe

    OpenAIRE

    Vicente Macas, Oswaldo David

    2009-01-01

    El transporte por cable es considerado como un medio de transporte independiente, diferente de los medios convencionales como lo son carretera, ferrocarril, aéreo, marítimo, y tubería. Es evidente que su importancia dentro del campo global de transporte es limitada, tanto en lo relativo a su importancia económica como en lo que se refiere a la capacidad de carga y distancias de recorrido. A pesar de todo lo mencionado es un sistema que se encuentra en un proceso de renovación y evolución t...

  16. Electronic structures and stability of Ni/Bi2Te3 and Co/Bi2Te3 interfaces

    KAUST Repository

    Xiong, Ka; Wang, Weichao; Alshareef, Husam N.; Gupta, Rahul P.; White, John B.; Gnade, Bruce E.; Cho, Kyeongjae

    2010-01-01

    We investigate the electronic structures and stability for Ni/Bi 2Te3, NiTe/Bi2Te3, Co/Bi 2Te3 and CoTe2/Bi2Te3 interfaces by first-principles calculations. It is found that the surface termination strongly affects the band alignment. Ni and Co are found to form Ohmic contacts to Bi2Te3. The interface formation energy for Co/Bi2Te3 interfaces is much lower than that of Ni/Bi2Te3 interfaces. Furthermore, we found that NiTe on Bi2Te3 is more stable than Ni, while the formation energies for Co and CoTe2 on Bi2Te3 are comparable. © 2010 IOP Publishing Ltd.

  17. Electronic structures and stability of Ni/Bi2Te3 and Co/Bi2Te3 interfaces

    International Nuclear Information System (INIS)

    Xiong Ka; Wang Weichao; Alshareef, Husam N; Gupta, Rahul P; Gnade, Bruce E; Cho, Kyeongjae; White, John B

    2010-01-01

    We investigate the electronic structures and stability for Ni/Bi 2 Te 3 , NiTe/Bi 2 Te 3 , Co/Bi 2 Te 3 and CoTe 2 /Bi 2 Te 3 interfaces by first-principles calculations. It is found that the surface termination strongly affects the band alignment. Ni and Co are found to form Ohmic contacts to Bi 2 Te 3 . The interface formation energy for Co/Bi 2 Te 3 interfaces is much lower than that of Ni/Bi 2 Te 3 interfaces. Furthermore, we found that NiTe on Bi 2 Te 3 is more stable than Ni, while the formation energies for Co and CoTe 2 on Bi 2 Te 3 are comparable.

  18. Electronic structures and stability of Ni/Bi2Te3 and Co/Bi2Te3 interfaces

    KAUST Repository

    Xiong, Ka

    2010-03-04

    We investigate the electronic structures and stability for Ni/Bi 2Te3, NiTe/Bi2Te3, Co/Bi 2Te3 and CoTe2/Bi2Te3 interfaces by first-principles calculations. It is found that the surface termination strongly affects the band alignment. Ni and Co are found to form Ohmic contacts to Bi2Te3. The interface formation energy for Co/Bi2Te3 interfaces is much lower than that of Ni/Bi2Te3 interfaces. Furthermore, we found that NiTe on Bi2Te3 is more stable than Ni, while the formation energies for Co and CoTe2 on Bi2Te3 are comparable. © 2010 IOP Publishing Ltd.

  19. Infrared and near infrared emission spectra of TeH and TeD

    Science.gov (United States)

    Yu, Shanshan; Shayesteh, Alireza; Fu, Dejian; Bernath, Peter F.

    2005-04-01

    The vibration-rotation emission spectra for the X2Π ground state and the near infrared emission spectra of the X2Π 1/2- X2Π 3/2 system of the TeH and TeD free radicals have been measured at high resolution using a Fourier transform spectrometer. TeH and TeD were generated in a tube furnace with a DC discharge of a flowing mixture of argon, hydrogen (or deuterium), and tellurium vapor. In the infrared region, for the X2Π 3/2 spin component we observed the 1-0, 2-1, and 3-2 vibrational bands for most of the eight isotopologues of TeH and the 1-0 and 2-1 bands for three isotopologues of TeD. For the X2Π 1/2- X2Π 3/2 transition, we observed the 0-0 and 1-1 bands for TeH and the 0-0, 1-1, and 2-2 bands for TeD. Except for a few lines, the tellurium isotopic shift was not resolved for the X2Π 1/2- X2Π 3/2 transitions of TeH and TeD. Local perturbations with Δ v = 2 between the two spin components of the X2Π state of TeH were found: X2Π 1/2, v = 0 with X2Π 3/2, v = 2; X2Π 1/2, v = 1 with X2Π 3/2, v = 3. The new data were combined with the previous data from the literature and two kinds of fits (Hund's case (a) and Hund's case (c)) were carried out for each of the 10 observed isotopologues: 130TeD, 128TeD, 126TeD, 130TeH, 128TeH, 126TeH, 125TeH, 124TeH, 123TeH, and 122TeH.

  20. La política comunitaria del cielo único europeo : reflexiones sobre su impacto en el principio de soberanía : repercusiones en la política de liberalización del transporte aéreo : principios y mecanismos de estructuración

    OpenAIRE

    Ospina Mosquera, Norma Constanza

    2005-01-01

    En los procesos de liberalización al interior de la integración europea, la liberalización del transporte aéreo significó un gran avance en la consolidación del mercado único. Sin embargo esta liberalización trajo consigo congestión en el espacio aéreo, situación que repercutió en la seguridad y eficiencia del sistema y conllevó a su vez la falta de competitividad de los mercados. Las causas de dicha ineficiencia tienen su origen en una organización del espacio aéreo irracional, fundada en un...

  1. High mobility 2D electron gas in CdTe/CdMgTe heterostructures

    International Nuclear Information System (INIS)

    Karczewski, G.; Jaroszynski, J.; Kurowski, M.; Barcz, A.; Wojtowicz, T.; Kossut, J.

    1997-01-01

    We report on iodine doping of molecular beam epitaxy (MBE)-grown Cd(Mn)Te quasi-bulk films and modulation-doped CdTe/Cd 1-y Mg y Te two-dimensional (2D) single quantum well structures. Modulation doping with iodine of CdTe/Cd 1-y Mg y Te structures resulted in fabrication of a 2D electron gas with mobility exceeding 10 5 cm 2 /(Vs). This is the highest mobility reported in wide-gap II-VI materials

  2. DIVERSIDAD DE LEVADURAS ASOCIADAS A INFLORESCENCIAS DE MANGO Y FLORES DE 'LULO ARBÓREO' DIVERSIDADE DE LEVEDURAS ASSOCIADAS A INFLORESCÊNCIAS DE MANGA E FLORES DE 'LULO ARBÓREO' YEAST DIVERSITY ASSOCIATED TO INFLORESCENCES OF MANGO AND FLOWERS OF 'LULO ARBOREO'

    Directory of Open Access Journals (Sweden)

    JACKELINE GAVIRIA V.

    2012-12-01

    Full Text Available En Colombia, el conocimiento de levaduras ha sido limitado a especies de interés clínico. El micro-hábitat aéreo de las flores, presenta un área de gran interés para el aislamiento de levaduras con importancia en el campo industrial, por su potencial uso como controlador biológico. El objetivo de este trabajo es analizar la diversidad de levaduras asociadas a inflorescencia de Mango (Mangífera índica y flores de Lulo arbóreo (Solanum wrightii. Para dicha finalidad se trabajó con 96 aislados, a los cuales se les realizó caracterización fenotípica y posteriores pruebas de MSP-PCR Fingerprinting. Estas pruebas fueron complementadas con amplificación parcial y secuenciación del segmento 26S del ADNr para identificación a nivel de especie. El patrón de diversidad encontrado refleja una dominancia de la especie Candida leandrae en flores de lulo arbóreo, también se presentaron especies como Cryptococcus laurentii, Candida parazyma, Aeurobasidium pullulans y Pseudozyma tsukubaensis. Las inflorescencias de mango presentaron especies como Sydowia eucalypti, Cryptococcus flavescens, C. laurentii, C. nemorosus, C. heveanensis, Pichia kluyveri, Pseudozyma tsukubaensis y Candida asparagi. Se logró identificar hasta el nivel taxonómico de especie el total de los aislados encontrados, además se hallaron especies con potencial uso biotecnológico.Na Colômbia, o conhecimento das leveduras é limitado a espécies de interesse clinico. O micro-habitat aéreo das flores apresenta um interessante campo para o isolamento de leveduras com importância na indústria pelo seu potencial uso em controle biológico. O objetivo deste trabalho foi analisar a diversidade de leveduras associadas a inflorescências de Manga (Mangifera indica e flores de 'lulo' (Solanum wrightii. Para isso, foram analisados 96 isolados, que foram caracterizados com testes fenotípicos e MSP-PCR Fingerprinting complementadas com sequenciamento parcial da região 26S do r

  3. Analysis of CdS/CdTe devices incorporating a ZnTe:Cu/Ti Contact

    International Nuclear Information System (INIS)

    Gessert, T.A.; Asher, S.; Johnston, S.; Young, M.; Dippo, P.; Corwine, C.

    2007-01-01

    High-performance CdS/CdTe photovoltaic devices can be produced using a ZnTe:Cu/Ti back contact deposited onto the CdTe layer. We observe that prolonged exposure of the ZnTe:Cu and Ti sputtering targets to an oxygen-containing plasma significantly reduces device open-circuit voltage and fill factor. High-resolution compositional analysis of these devices reveals that Cu concentration in the CdTe and CdS layers is lower for devices with poor performance. Capacitance-voltage analysis and related numerical simulations indicate that the net acceptor concentration in the CdTe is also lower for devices with poor performance. Photoluminescence analyses of the junction region reveal that the intensity of a luminescent peak associated with a defect complex involving interstitial Cu (Cu i ) and oxygen on Te (O Te ) is reduced in devices with poor performance. Combined with thermodynamic considerations, these results suggest that oxygen incorporation into the ZnTe:Cu sputtering target reduces the ability of sputtered ZnTe:Cu film to diffuse Cu into the CdTe

  4. INTRAOCULAR TRANSMISSIBLE VENEREAL TUMOR IN A DOG TUMOR VENÉREO TRANSMISSÍVEL INTRA-OCULAR EM CÃO

    Directory of Open Access Journals (Sweden)

    Geórgia Nadalini Rodrigues

    2001-02-01

    Full Text Available Canine transmissible venereal tumor (TVT is a round cell neoplasm occurring on the external genital mucosa of male and female dogs. Transmission is by cell implantation during coitus, licking, or other interaction between an affected dog and a susceptible host. Metastasis of the tumor rarely occurs. This report describes an unusual presentation of TVT with intraocular involvement and inguinal lymph nodes metastasis. The subject was a six-year-old, intact, male, Brazilian Terrier dog with a history of abnormal masses in the right eye, penis and several subcutaneous nodules in the inguinal area. Histopathological examination of the eye specimens as well as cytologic examination of penile mass and subcutaneous nodules revealed similar findings. The examination revealed round cells containing a large nuclei with prominent, central located nucleoli and a pale cytoplasm containing few small, clear round vacuoles. Histologically, the subcutaneous nodules in the inguinal area were lymph nodes. The diagnosis of TVT with intraocular involvement and lymph nodes metastasis was based on clinical, cytologic and histopathologic findings.Tumor venéreo transmissível (TVT é uma neoplasia de células redondas que acomete a mucosa genital externa de cães, machos e fêmeas. A transmissão decorre da implantação de células tumorais durante o coito, brigas ou interações entre animais portadores e susceptíveis. Existem relatos referindo-se a localizações atípicas do TVT, mas metástases raramente ocorrem. O presente relato descreve um caso incomum de TVT, com acometimento intra-ocular e metástases nos linfonodos ingüinais, num cão Terrier Brasileiro, com seis anos de idade. O animal apresentava massas anormais de tecido no olho direito, extremidade do pênis e aumento de volume de linfonodos da região ingüinal. A histopatologia do globo ocular e as citologias da massa peniana e dos nódulos subcutâneos evidenciaram aspectos citológicos semelhantes

  5. Estrutura do componente arbóreo em áreas de cerrado no município de São Tomé das Letras, MG

    Directory of Open Access Journals (Sweden)

    Renata de Melo Ferreira Lopes

    2013-10-01

    Full Text Available O município de São Tomé das Letras localiza-se ao sul de Minas Gerais, na bacia do rio Grande, em área de transição entre a Floresta Atlântica e o Cerrado, onde se distinguem também campos rupestres. Possui economia baseada em extrativismo mineral, agropecuária e turismo. Este trabalho teve como objetivo determinar a estrutura fitossociológica de três áreas de cerrado no município. Foram amostrados 60 pontos-quadrantes por área, tomando-se medidas de altura das árvores e circunferência de tronco (≥ 10 cm à altura do solo. Foram calculados para cada ambiente: densidade de indivíduos, dominância, frequência, área basal, Valor de Importância (VI e diversidade florística (Índice de Shannon, H'. Ao todo, foram identificadas 27 famílias, 36 gêneros e 56 espécies. Eremanthus erythropappus (candeia, Asteraceae foi a espécie de maior Valor de Importância (VI encontrada nas áreas Candeias e Vale das Borboletas e Stryphnodendron adstringens (barbatimão, Fabaceae e Piptocarpha rotundifolia (coração-de-negro, Asteraceae as espécies que se destacaram em VI na área Carrapatos. A altura média variou de 2,0 ± 1,2 a 2,3 ± 1,3m. O diâmetro médio variou de 6,5 ± 4,4 a 7,3 ± 4,8 cm. A densidade média foi de 2315 indiv.ha-1 e área basal média de 13,4 m².ha-1. O índice de diversidade de Shannon (H' para espécies variou de 2,67 a 2,96 nats/ind. Foi observada baixa similaridade de espécies entre as três áreas. Considerando as pressões antrópicas que os ambientes naturais da região vêm sofrendo, os dados obtidos poderão subsidiar projetos locais de recomposição da vegetação, principalmente do componente arbóreo.

  6. Corrección de la clorosis férrica con quelato EDDHA en cultivos sembrados en suelo alcalino y calcáreo

    Directory of Open Access Journals (Sweden)

    Arturo Díaz Franco

    2018-01-01

    Full Text Available La deficiencia de hierro (Fe en los cultivos se manifiesta principalmente en regiones con suelos alcalinos y calcáreos. En el presente estudio se evaluó la efectividad del Fe3+ quelatado con EDDHA [ac. etilendiamino di-(o-hidroxifenilacetato] y la aspersión foliar de FeSO4 solos y combinados, en los cultivos de sorgo, soya, okra y frijol. El EDDHA-Fe (Ultraferro® se aplicó a dosis de 1% en la siembra sobre las semillas y para el FeSO4 se hicieron dos aplicaciones foliares al 1.5%. En los cuatro experimentos se determinó el índice de clorofila (SPAD en tres fechas (15 y 28 de marzo, 6 de abril, y a los 48-50 días después de la siembra se cuantificó la biomasa foliar y radical. Entre los cultivos, las plantas de soya y okra manifestaron la mayor intensidad de clorosis férrica, la cual fue visible entre los tratamientos. En ambos cultivos los mayores valores SPAD y de biomasa foliar y radical se obtuvieron con la aplicación de EDDHA-Fe solo o combinado con FeSO4. En frijol y sorgo, la clorosis fue menos visible, para las plantas de frijol el mayor índice de clorofila se registró con EDDHA-Fe y FeSO4 en las dos últimas fechas de evaluación (28 de marzo y 6 de abril y los tres tratamientos químicos superaron de forma similar al testigo, en la biomasa foliar y radical. Las plantas de sorgo registraron los mayores índices SPAD en la última fecha (6 de abril, mientras que no fueron significativas las diferencias en la biomasa foliar y radical. No se observó efecto aditivo en las variables con la combinación EDDHA-Fe y FeSO4. En general, los resultados indican que la aplicación de EDDHA-Fe solo o combinado con FeSO4 foliar en soya, okra y frijol, mostraron corrección de la clorosis férrica de manera efectiva.

  7. U-Pb, Re-Os and Ar-Ar dating of the Linghou polymetallic deposit, Southeastern China: Implications for metallogenesis of the Qingzhou-Hangzhou metallogenic belt

    Science.gov (United States)

    Tang, Yanwen; Xie, Yuling; Liu, Liang; Lan, Tingguan; Yang, Jianling; Sebastien, Meffre; Yin, Rongchao; Liang, Songsong; Zhou, Limin

    2017-04-01

    The Qingzhou-Hangzhou metallogenic belt (QHMB) in Southeastern China has gained increasingly attention in recent years. However, due to the lack of reliable ages on intrusions and associated deposits in this belt, the tectonic setting and metallogenesis of the QHMB have not been well understood. The Linghou polymetallic deposit in northwestern Zhejiang Province is one of the typical deposits of the QHMB. According to the field relationships, this deposit consists of the early Cu-Au-Ag and the late Pb-Zn-Cu mineralization stages. Molybdenite samples with a mineral assemblage of molybdenite-chalcopyrite-pyrite ± quartz are collected from the copper mining tunnel near the Cu-Au-Ag ore bodies. Six molybdenite samples give the Re-Os model ages varying from 160.3 to 164.1 Ma and yield a mean age of 162.2 ± 1.4 Ma for the Cu-Au-Ag mineralization. Hydrothermal muscovite gives a well-defined Ar-Ar isochron age of 160.2 ± 1.1 Ma for the Pb-Zn-Cu mineralization. Three phases of granodioritic porphyry have been distinguished in this deposit, and LA-ICP-MS zircon U-Pb dating shows that they have formed at 158.8 ± 2.4 Ma, 158.3 ± 1.9 Ma and 160.6 ± 2.1 Ma, comparable to the obtained ages of the Cu-Au-Ag and Pb-Zn-Cu mineralization. Therefore, these intrusive rocks have a close temporal and spatial relationship with the Cu-Au-Ag and Pb-Zn-Cu ore bodies. The presences of skarn minerals (e.g., garnet) and vein-type ores, together with the previous fluid inclusion and H-O-C-S-Pb isotopic data, clearly indicate that the Cu-Au-Ag and Pb-Zn-Cu mineralization are genetically related to these granodiorite porphyries. This conclusion excludes the possibility that this deposit is of ;SEDEX; type and formed in a sag basin of continental rifts setting as previously proposed. Instead, it is proposed that the Linghou polymetallic and other similar deposits in the QHMB, such as the 150-160 Ma Yongping porphyry-skarn Cu-Mo, Dongxiang porphyry? Cu, Shuikoushan/Kangjiawang skarn Pb

  8. Condicionantes macroeconômicos e regulatórios da determinação da capacidade produtiva: estudo de caso do setor aéreo

    Directory of Open Access Journals (Sweden)

    Humberto Filipe de Andrade Januário Bettini

    2009-03-01

    Full Text Available Este trabalho objetiva identificar fatores macroeconômicos, regulatórios e concorrenciais que afetam a decisão de empresas quanto ao dimensionamento de sua capacidade produtiva. Foi desenvolvido um estudo de caso do transporte aéreo - aproveitando de uma especificidade do setor - que requer a tomada de decisão quanto à capacidade em cada submercado (par de aeroportos operado. Buscou-se identificar o processo decisório das firmas utilizando-se um painel de dados tridimensional desagregado ao nível da empresa-mercado-tempo. Resultados finais mostraram que: 1. agregados macroeconômicos, como o PIB e a taxa de câmbio, têm impacto estatisticamente significante na formação da capacidade; 2. as medidas advindas do período da quase-desregulamentação do setor, a partir de 2001, tiveram pouco impacto sobre a capacidade, medida pela oferta de assentos; e, por fim, 3. a associação estabelecida entre as duas maiores empresas do setor, em 2003, teve impactos relevantes, ilustrando o fato de que maior dominância afeta a tomada de decisão quanto à oferta, e requer, assim, maior acompanhamento antitruste.This article aims at identifying elements that affect the decision firms make in what concerns productive capacity setting in markets. Among these elements, macroeconomic, regulatory and competition factors are highlighted. In this paper, a case study for the domestic scheduled airline industry is developed, taking advantage of the particularity of this sector, in which an airline ought to decide capacities in each sub-market (pair of airports where it is present. By using a three-dimensional panel of data (airline-market-time, we propose an identification of this decision-making process. Among the final results, it can be highlighted that: 1. macroeconomic aggregates such as GDP and exchange rate have significant impact over the decision process of capacity setting; 2. liberalizing measures adopted in 2001 and lasting for the two following

  9. Self-Catalyzed CdTe Wires

    Directory of Open Access Journals (Sweden)

    Tom Baines

    2018-04-01

    Full Text Available CdTe wires have been fabricated via a catalyst free method using the industrially scalable physical vapor deposition technique close space sublimation. Wire growth was shown to be highly dependent on surface roughness and deposition pressure, with only low roughness surfaces being capable of producing wires. Growth of wires is highly (111 oriented and is inferred to occur via a vapor-solid-solid growth mechanism, wherein a CdTe seed particle acts to template the growth. Such seed particles are visible as wire caps and have been characterized via energy dispersive X-ray analysis to establish they are single phase CdTe, hence validating the self-catalysation route. Cathodoluminescence analysis demonstrates that CdTe wires exhibited a much lower level of recombination when compared to a planar CdTe film, which is highly beneficial for semiconductor applications.

  10. A thermodynamic stability of bulk and epitaxial CdHgTe, ZnHgTe and MnHgTe solid solutions

    International Nuclear Information System (INIS)

    Dejbuk, V.G.; Dremlyuzhenko, S.G.; Ostapov, S.Eh.

    2005-01-01

    A thermodynamics of Cd 1-x Hg x Te, Zn x Hg 1-x Te and Mg x Hg 1-x Te alloys has been investigated for a delta-lattice parameter model. The phase diagrams obtained show the stability of Cd 1-x Hg x Te, Zn x Hg 1-x Te in the whole range of compositions, alongside with a miscibility gap for Mn x Hg 1-x Te being of 0.35 x Hg 1-x Te/CdTe and Mn x Hg 1-x Te/Cd 0.96 Zn 0.04 Te epitaxial films result in lowering critical temperatures and narrowing the miscibility gap [ru

  11. Enlaces de datos En VHF (VDL dentro del contexto CNS/ATM para la prestación de los servicios de tránsito aéreo en Colombia

    Directory of Open Access Journals (Sweden)

    Édgar Leonardo Gómez Gómez

    2012-09-01

    Full Text Available En este artículo se analiza el protocolo de comunicaciones por enlaces de datos en VHF (VDL, el cual, junto con técnicas de posicionamiento satelital, es uno de los pilares fundamentales dentro del concepto CNS/ATM planteado por la Organización de Aviación Civil Internacional (OACI, el cual busca la implantación de nuevas tecnologías para la prestación de los servicios de tránsito aéreo en las áreas de comunicaciones, navegación y vigilancia de aeronaves a nivel mundial. Se presenta el tipo de sistemas usados actualmente por la Unidad Administrativa Especial de Aeronáutica Civil (UAEAC para la prestación de estos servicios en Colombia, y se hace un comparativo para establecer las ventajas que tiene la implantación de las nuevas tecnologías planteadas en el concepto CNS/ATM, teniendo en cuenta las condiciones particulares de terreno y de flujo de tránsito aéreo que presenta Colombia. Además, se presentan los proyectos de implementación de subredes basadas en enlaces de datos VDL más relevantes a nivel mundial, los cuales permiten obtener resultados de pruebas de funcionamiento, como un paso fundamental hacia la consolidación a nivel mundial de este tipo de tecnología.

  12. Desenvolvimento de banco de dados para estudo sobre ocorrências médicas no espaço aéreo brasileiro = The development of a database for the study of medical occurrences in the Brazilian airspace

    Directory of Open Access Journals (Sweden)

    Santos, Ricardo Vieira

    2013-01-01

    Full Text Available O aumento do número de passageiros transportados ao ano, devido à crescente demanda por serviços aéreos, resulta em uma ampliação das ocorrências médicas a bordo de aeronaves. Por esta razão, a importância da implantação de sistemas de segunda-opinião a distância são cada vez mais relevantes na condução desses eventos. Dado o contexto apresentado, este estudo tem o objetivo de desenvolver um banco de dados que subsidie estudos sobre ocorrências médicas a bordo de aeronaves que operam no espaço aéreo brasileiro. Para tanto, foram mapeados os aeroportos utilizados pelas companhias aéreas brasileiras junto aos hospitais de referência próximos a estes aeroportos e identificadas as principais ocorrências médicas a bordo. Dessa forma, pretende-se melhor definir a realidade das companhias aéreas quanto ao atendimento de ocorrências médicas a bordo

  13. A new type of one-dimensional compound: Structure of Nb4(Te2)4Te4I

    International Nuclear Information System (INIS)

    Deng Shuiquan; Zhuang Honghui; Lu Canzhong; Huang Jinshun; Huang Jingling

    1993-01-01

    The new infinite-chain niobium telluride iodide has been prepared by reaction of the elements at 893 K. Nb 4 (Te 2 ) 4 Te 4 I represents a new one-dimensional structure type. The structure consists of [Nb 4 (Te 2 ) 4 Te 4 I] ∞ chains which are formed by the four-nuclear butterfly cluster units 'Nb 4 (Te 2 ) 4 Te 4 ' with the I atoms bridging between different cluster units. (orig.)

  14. Re-Os systematics and geochemistry of cobaltite (CoAsS) in the Idaho cobalt belt, Belt-Purcell Basin, USA: Evidence for middle Mesoproterozoic sediment-hosted Co-Cu sulfide mineralization with Grenvillian and Cretaceous remobilization

    Science.gov (United States)

    Saintilan, N.J.; Creaser, R.A.; Bookstrom, Arthur A.

    2017-01-01

    We report the first study of the Re-Os systematics of cobaltite (CoAsS) using disseminated grains and massive sulfides from samples of two breccia-type and two stratabound deposits in the Co-Cu-Au Idaho cobalt belt (ICB), Lemhi subbasin to the Belt-Purcell Basin, Idaho, USA. Using a 185Re + 190Os spike solution, magnetic and non-magnetic fractions of cobaltite mineral separates give reproducible Re-Os analytical data for aliquot sizes of 150 to 200 mg. Cobaltite from the ICB has highly radiogenic 187Os/188Os ratios (17–45) and high 187Re/188Os ratios (600–1800) but low Re and total Os contents (ca. 0.4–4 ppb and 14–64 ppt, respectively). Containing 30 to 74% radiogenic 187Os, cobaltite from the ICB is amenable to Re-Os age determination using the isochron regression approach.Re-Os data for disseminated cobaltite mineralization in a quartz-tourmaline breccia from the Haynes-Stellite deposit yield a Model 1 isochron age of 1349 ± 76 Ma (2σ, n = 4, mean squared weighted deviation MSWD = 2.1, initial 187Os/188Os ratio = 4.7 ± 2.2). This middle Mesoproterozoic age is preserved despite a possible metamorphic overprint or a pulse of metamorphic-hydrothermal remobilization of pre-existing cobaltite that formed along fold cleavages during the ca. 1190–1006 Ma Grenvillian orogeny. This phase of remobilization is tentatively identified by a Model 3 isochron age of 1132 ± 240 Ma (2σ, n = 7, MSWD = 9.3, initial 187Os/188Os ratio of 9.0 ± 2.9) for cobaltite in the quartz-tourmaline breccia from the Idaho zone in the Blackbird mine.All Mesoproterozoic cobaltite mineralization in the district was affected by greenschist- to lower amphibolite-facies (garnet zone) metamorphism during the Late Jurassic to Late Cretaceous Cordilleran orogeny. However, the fine- to coarse-grained massive cobaltite mineralization from the shear zone-hosted Chicago zone, Blackbird mine, is the only studied deposit that has severely disturbed Re-Os

  15. Precipitation of Ag2Te in the thermoelectric material AgSbTe2

    International Nuclear Information System (INIS)

    Sugar, Joshua D.; Medlin, Douglas L.

    2009-01-01

    The microstructure of AgSbTe 2 , prepared by solidification, is investigated using electron microscopy. During solidification and thermal treatment, the material separates into a two-phase mixture of a rocksalt phase, which is Ag 22 Sb 28 Te 50 , and silver telluride, Ag 2 Te. Ag 2 Te formation results either from eutectic solidification (large lamellar structures), or by solid-state precipitation (fine-scale particles). The crystal structure of the AgSbTe 2 phase determined by electron diffraction is consistent with a rocksalt structure that has a disordered cation sublattice. A preferred crystallographic orientation relationship at the interface between the matrix and the low-temperature monoclinic Ag 2 Te phase is defined and discussed. This orientation relationship is observed for both second-phase morphologies. In both cases, the orientation relationship originates from a topotactic (cube-on-cube) alignment of the Te sublattices in the initially cubic Ag 2 Te and the matrix at elevated temperature. This Te sublattice alignment is retained as the Ag 2 Te undergoes a cubic-to-monoclinic transformation during cooling. This orientation relationship is observed for both second-phase morphologies.

  16. Pulsar TeV Halos Explain the Diffuse TeV Excess Observed by Milagro.

    Science.gov (United States)

    Linden, Tim; Buckman, Benjamin J

    2018-03-23

    Milagro observations have found bright, diffuse TeV emission concentrated along the galactic plane of the Milky Way. The intensity and spectrum of this emission is difficult to explain with current models of hadronic γ-ray production, and has been named the "TeV excess." We show that TeV emission from pulsars naturally explains this excess. Recent observations have detected "TeV halos" surrounding pulsars that are either nearby or particularly luminous. Extrapolating this emission to the full population of Milky Way pulsars indicates that the ensemble of "subthreshold" sources necessarily produces bright TeV emission diffusively along the Milky Way plane. Models indicate that the TeV halo γ-ray flux exceeds that from hadronic γ rays above an energy of ∼500  GeV. Moreover, the spectrum and intensity of TeV halo emission naturally matches the TeV excess. Finally, we show that upcoming HAWC observations will resolve a significant fraction of the TeV excess into individual TeV halos, conclusively confirming, or ruling out, this model.

  17. RHEED studies of MBE growth mechanisms of CdTe and CdMnTe

    Energy Technology Data Exchange (ETDEWEB)

    Waag, A.; Behr, T.; Litz, T.; Kuhn-Heinrich, B.; Hommel, D.; Landwehr, G. (Physikalisches Inst., Univ. Wuerzburg (Germany))

    1993-01-30

    We report on reflection high energy electron diffraction (RHEED) studies of molecular beam epitaxy (MBE) growth of CdTe and CdMnTe on (100) oriented CdTe substrates. RHEED oscillations were measured for both the growth and desorption of CdTe and CdMnTe as a function of flux and temperature. For the first time, the influence of laser and electron irradiation on the growth rate, as well as desorption, of CdTe is studied in detail using RHEED oscillations. We found a very small effect on the growth rate as well as on the CdTe desorption rate. The growth rate of CdTe was determined for different temperatures and CdTe flux ratios. The obtained experimental results are compared with a kinetic growth model to get information on the underlying growth processes, taking into account the influence of a precursor by including surface diffusion. From the comparison between model and experimental results the sticking coefficients of Cd and Te are determined. The growth rate of CdMnTe increases with Mn flux. This dependence can be used to calibrate the Mn content during growth by comparing the growth rate of CdTe with the growth rate of CdMnTe. The change in growth rate has been correlated with Mn content via photoluminescence measurements. In addition, the sticking coefficient of Mn is derived by comparing experimental results with a kinetic growth model. For high manganese content a transition to three-dimensional growth occurs. (orig.).

  18. Si-Sb-Te materials for phase change memory applications

    International Nuclear Information System (INIS)

    Rao Feng; Song Zhitang; Ren Kun; Zhou Xilin; Cheng Yan; Wu Liangcai; Liu Bo

    2011-01-01

    Si-Sb-Te materials including Te-rich Si 2 Sb 2 Te 6 and Si x Sb 2 Te 3 with different Si contents have been systemically studied with the aim of finding the most suitable Si-Sb-Te composition for phase change random access memory (PCRAM) use. Si x Sb 2 Te 3 shows better thermal stability than Ge 2 Sb 2 Te 5 or Si 2 Sb 2 Te 6 in that Si x Sb 2 Te 3 does not have serious Te separation under high annealing temperature. As Si content increases, the data retention ability of Si x Sb 2 Te 3 improves. The 10 years retention temperature for Si 3 Sb 2 Te 3 film is ∼ 393 K, which meets the long-term data storage requirements of automotive electronics. In addition, Si richer Si x Sb 2 Te 3 films also show improvement on thickness change upon annealing and adhesion on SiO 2 substrate compared to those of Ge 2 Sb 2 Te 5 or Si 2 Sb 2 Te 6 films. However, the electrical performance of PCRAM cells based on Si x Sb 2 Te 3 films with x > 3.5 becomes worse in terms of stable and long-term operations. Si x Sb 2 Te 3 materials with 3 < x < 3.5 are proved to be suitable for PCRAM use to ensure good overall performance.

  19. Growth and optical properties of CdTe quantum dots in ZnTe nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Wojnar, Piotr; Janik, Elzbieta; Baczewski, Lech T.; Kret, Slawomir; Karczewski, G.; Wojtowicz, Tomasz [Institute of Physics, Polish Academy of Sciences, Al Lotnikow 32/46, 02-668 Warsaw (Poland); Goryca, Mateusz; Kazimierczuk, Tomasz; Kossacki, Piotr [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul Hoza 69, 00-681 Warsaw (Poland)

    2011-09-12

    We report on the formation of optically active CdTe quantum dots in ZnTe nanowires. The CdTe/ZnTe nanostructures have been grown by a gold nanocatalyst assisted molecular beam epitaxy in a vapor-liquid solid growth process. The presence of CdTe insertions in ZnTe nanowire results in the appearance of a strong photoluminescence band in the 2.0 eV-2.25 eV energy range. Spatially resolved photoluminescence measurements reveal that this broad emission consists of several sharp lines with the spectral width of about 2 meV. The large degree of linear polarization of these individual emission lines confirms their nanowire origin, whereas the zero-dimensional confinement is proved by photon correlation spectroscopy.

  20. Electrical and optical properties of SnEuTe and SnSrTe films

    Science.gov (United States)

    Ishida, Akihiro; Tsuchiya, Takuro; Yamada, Tomohiro; Cao, Daoshe; Takaoka, Sadao; Rahim, Mohamed; Felder, Ferdinand; Zogg, Hans

    2010-06-01

    The SnTe, Sn1-xEuxTe and Sn1-xSrxTe (x<0.06) films were prepared by hot wall epitaxy. The ternary alloy films prepared in cation rich condition had hole concentration around 1×1019 cm-3 with high mobility exceeding 2000 cm2/V s at room temperature. Optical transmission spectra were also measured in the temperature range from 100 to 400 K and compared with theoretical calculations. Optical transmission spectra of the SnTe were simulated successfully assuming bumped band edge structures. A band inversion model was proposed for the Sn1-xEuxTe and Sn1-xSrxTe systems, and the optical transmission spectra were also simulated successfully assuming the band inversion model.

  1. Cu-Mo-Au mineralization in Qarachilar area, Qaradagh batholith (NW Iran): Fluid inclusion and stable isotope studies and Re-Os dating

    Science.gov (United States)

    Simmonds, Vartan; Moazzen, Mohssen

    2015-04-01

    disappearance display TH values between 300 and 360 °C. The data-point trend in TH(L-V)-Salinity plot may signify boiling of low-salinity fluids and distillation by superficial fluids. Therefore, it can be concluded that the ore-forming magmatic-hydrothermal aqueous fluids have most likely experienced boiling and also mixed with low temperature and low salinity superficial fluids. Occurrence of boiling is also supported by the coexistence of liquid-rich and vapor-rich 2-phase inclusions as well as multi-phase halite-bearing inclusions which homogenize in a similar range of TH. The calculated minimum pressure at the time of entrapment is estimated about 50 to 120 bar, which is equal to the hydrostatic depth of 500-1100 m. Stable isotope studies of O, H and S on the quartz and sulfide samples taken from quartz-sulfide veins-veinlets reveal a magmatic origin for the ore-bearing fluid and its sulfur content. The δ18O values for quartz and fluid are about 11.13-12.47 ‰ and 5.78-6.89 ‰ (SMOW), respectively, the δD values are about -93 and -50 ‰ and the δ34S values of sulfide minerals are about -1.37-0.49‰ (VCDT). Re-Os model ages calculated for molybdenite samples range between 25.19±0.19 and 31.22±0.28 Ma, referring to middle-late Oligocene, contemporaneous with the third metallogenic epoch in the Lesser Caucasus (especially Kadjaran and Paragachai PCDs in South Armenian Block).

  2. BOREAS TE-17 Production Efficiency Model Images

    Data.gov (United States)

    National Aeronautics and Space Administration — A BOREAS version of the Global Production Efficiency Model(www.inform.umd.edu/glopem) was developed by TE-17 to generate maps of gross and net primary production,...

  3. Linear accelerators for TeV colliders

    International Nuclear Information System (INIS)

    Wilson, P.B.

    1985-05-01

    This paper summarizes four tutorial lectures on linear electron accelerators: Electron Linacs for TeV Colliders, Emittance and Damping Rings, Wake Fields: Basic Concepts, and Wake Field Effects in Linacs

  4. Intern transport beter te plannen met computer

    NARCIS (Netherlands)

    Annevelink, E.

    1999-01-01

    Verbetering van intern transport in de potplantenteelt. Door getoetste vuistregels te combineren met toegepaste wiskunde is automatische planning van het intern transport binnen handbereik. Dit leidt tot minder transportbewegingen en tijdsbesparing bij het plannen

  5. Perspective on TeV-scale physics

    International Nuclear Information System (INIS)

    Chanowitz, M.S.

    1989-02-01

    These lectures review theoretical motivations and experimental prospects for the study of TeV-scale physics. Three clues to the importance of TeV physics are discussed: implications of quantum corrections for the masses of a fourth generation quark-lepton family, the gauge hierarchy problem and known solutions, and implications of symmetry and unitarity for the symmetry-breaking sector of the electroweak gauge theory. The experimental prospects are reviewed with emphasis on the multi-TeV pp colliders that may be built in the 1990's. The topics include new phenomena that might occur - e.g., a fourth generation, heavy gauge bosons, composite structure, and supersymmetry - as well as the signals of the unknown SU(2)/sub L/ /times/ U(1)/sub Y/ breaking mechanism that must occur within the TeV domain. 96 refs., 21 figs

  6. Hoe leer je iemand effectief te leren?

    NARCIS (Netherlands)

    Kester, Liesbeth; Koper, Rob; Gijselaers, Jérôme; Bahreini, Kiavash; De Vries, Fred; Wetzels, Sandra; Kirschner, Paul A.; Berkhout, Jeroen; Storm, Jeroen

    2012-01-01

    Kester, L., Koper, R., Gijselaers, J., Bahreini, K., De Vries, F., Berkhout, J., & Storm, J. (2012, 30 maart). Hoe leer je iemand effectief te leren? Masterclass in de OpenU community. Open universiteit, Heerlen, Nederland. Beschikbaar op

  7. TeSLA e-assessment workshop

    NARCIS (Netherlands)

    Janssen, José

    2016-01-01

    Presentatie ten behoeve van de e-assessment workshop voor docenten van de Open Universiteit Nederland betrokken in de eerste TeSLA pilot. Topics: toetsfraude, toetsdesign, technologie voor authenticatie en verificatie van auteurschap.

  8. Matrix-controlled morphology evolution of Te inclusions in CdZnTe single crystal

    International Nuclear Information System (INIS)

    He, Yihui; Jie, Wanqi; Xu, Yadong; Wang, Tao; Zha, Gangqiang; Yu, Pengfei; Zheng, Xin; Zhou, Yan; Liu, Hang

    2012-01-01

    The fine morphologies of microscale Te inclusions in CdZnTe single crystal were investigated to reveal their shape evolution. Such inclusions from crystal ingots with different post-growth cooling rates were analyzed using scanning electron microscopy after surface treatment. A tetrakaidecahedron model embodying {1 0 0} and {1 1 1} matrix facets was developed to interpret the form of the Te inclusions. An entire shape evolution process was also proposed where the final configuration of the Te inclusions was a tetrahedron comprising {1 1 1}B facets.

  9. CuGaTe2-CuAlTe2 system

    International Nuclear Information System (INIS)

    Bodnar', I.V.

    2003-01-01

    The results of studies on the chemical interaction in the CuGaTe 2 -CuAlTe 2 as well as on the thermal and optical properties of the formed solid solutions are presented. It is shown, that continuous number of solid solutions are formed in the CuGaTe 2 -CuAlTe 2 system, which crystallize in the chalcopyrite structure. The diagram of state of this system is plotted. The thermal expansion of these materials is studied through the dilatometric method. The linear dependence of the thermal expansion coefficient on the composition is established. The concentration dependences of the forbidden zone width diverge from the linearity [ru

  10. Formation of self assembled PbTe quantum dots in CdTe on Si(111)

    Science.gov (United States)

    Felder, F.; Fognini, A.; Rahim, M.; Fill, M.; Müller, E.; Zogg, H.

    2010-01-01

    We describe the growth and formation of self assembled PbTe quantum dots in a CdTe host on a silicon (111) substrate. Annealing yields different photoluminescence spectra depending on initial PbTe layer thickness, thickness of the CdTe cap layer and annealing temperature. Generally two distinct emission peaks at ˜0.3 eV and ˜0.45 eV are visible. Model calculations explaining their temperature dependence are performed. The dot size corresponds well with the estimated sizes from electron microscopy images. The quantum dots may be used as absorber within a mid-infrared detector.

  11. HgTe based topological insulators

    International Nuclear Information System (INIS)

    Bruene, Christoph

    2014-01-01

    This PhD thesis summarizes the discovery of topological insulators and highlights the developments on their experimental observations. The work focuses on HgTe. The thesis is structured as follows: - The first chapter of this thesis will give a brief overview on discoveries in the field of topological insulators. It focuses on works relevant to experimental results presented in the following chapters. This includes a short outline of the early predictions and a summary of important results concerning 2-dimensional topological insulators while the final section discusses observations concerning 3-dimensional topological insulators. - The discovery of the quantum spin Hall effect in HgTe marked the first experimental observation of a topological insulator. Chapter 2 focuses on HgTe quantum wells and the quantum spin Hall effect. The growth of high quality HgTe quantum wells was one of the major goals for this work. In a final set of experiments the spin polarization of the edge channels was investigated. Here, we could make use of the advantage that HgTe quantum well structures exhibit a large Rashba spin orbit splitting. - HgTe as a 3-dimensional topological insulator is presented in chapter 3. - Chapters 4-6 serve as in depth overviews of selected works: Chapter 4 presents a detailed overview on the all electrical detection of the spin Hall effect in HgTe quantum wells. The detection of the spin polarization of the quantum spin Hall effect is shown in chapter 5 and chapter 6 gives a detailed overview on the quantum Hall effect originating from the topological surface state in strained bulk HgTe.

  12. The system SnTe-InSe

    International Nuclear Information System (INIS)

    Gurshumov, A.P.; Alidzhanov, M.A.; Aliev, A.S.; Gadzhiev, T.G.; Mamedov, N.A.

    1986-01-01

    This paper discusses the nature of the interaction and physicochemical properties of the alloys of the system SnTe-InSe. The DTA was performed on an NTR-74 pyrometer, XPA on a Dron-2.0 diffractometer and MSA on an MIM-7 metallographic microscope. The microhardness of the samples was determined on a PMT-3 microhardness tester. The congruently melting compound SnInTeSe and solid solutions based on the starting components are formed in the system

  13. Efecto de la concentración de SO2 en las reacciones de calcinación y sulfatación de calcáreos en reactores de lecho fluidizado.

    Directory of Open Access Journals (Sweden)

    J. E. Lindo Samaniego

    2008-01-01

    Full Text Available Fue realizado un estudio sobre el efecto de las concentraciones de SO2 en la absorción por calcáreo en hornos de Lecho Fluidizado. Para observar la influencia del SO2 en los parámetros de diferentes procesos físicos y químicos fueron creados ambientes para cuatro concentraciones diferentes de SO2 : 500, 1000, 2000 y 4000 ppm. Se utilizaron dos tipos de calcáreos: Dolimitico-DP y el Calcítico-CI. El Lecho Fluidizado Burbujeante utilizado tiene 160 mm de diámetro interno y fue fluidizado con aire a la temperatura de 850 °C, con una concentración de SO2 deseada. Como material del lecho fue utilizada la arena de cuarzo (99,9% con diámetro de 385 µm y de masa aproximadamente 3,0 kg. El calcáreo fue adicionado en dosificación de 50 g con el reactor ya pre-calentado. Las variaciones de las concentraciones de SO2, CO2, CO, O2 y las descargas, fueron monitoreadas continuamente a la salida del ciclón que fue utilizado para la retención de la partícula fina. Para esos dados se desarrolló un programa en LabView. El modelo matemático escogido posibilitó la determinación de la conversión.A study of the effect of the concentrations of SO2 in its absorption by limestones in fluidized bed furnaces was conducted. For the determination of the SO2 influence on the different physical and chemical parameters of process, such as calcinations and sulfatation four different atmospheres were used in the reator with concentrations of SO2 of 500, 1000, 2000 and 4000 ppm. Two types of limestones were used: Dolomite-DP and Calcitic-CI. The bench scale bubbling fluidized bed reactor had a 160 mm internal diameter and was fluidized with air at 850 °C containing the required concentration of SO2. Bed material was quartz sand (99,9% , with 385 µm diameter and approximately 3 kg of mass. The limestone was introduced in samples of 50 kg in the reactor previously stabilized and their discharges in the reactor exit were continually monitored. For the

  14. In-situ U-Pb, Hf and Re-Os isotopic analyses of the Xiangshan Ni-Cu-Co deposit in Eastern Tianshan (Xinjiang), Central Asia Orogenic Belt: Constraints on the timing and genesis of the mineralization

    Science.gov (United States)

    Han, Chunming; Xiao, Wenjiao; Zhao, Guochun; Ao, Songjian; Zhang, Jien; Qu, Wenjun; Du, Andao

    2010-12-01

    The timing and genesis of the major Ni-Cu-Co sulfide deposit in the Xiangshan intrusion have been studied based on newly obtained in-situ U-Pb, Hf and Re-Os isotopic analyses. The SIMS U-Pb zircon ages of the gabbro hosting the Ni-Cu-Co sulfide deposit indicate that the Xiangshan intrusion was emplaced at 279.6 ± 1.1 Ma (95% confidence level, MSWD = 1.30, n = 15). On the basis of combined geological and geochronological evidence, we suggest that the Xiangshan and other adjacent Ni-Cu deposits were formed in the same period. Sulphides have low common Os concentrations and high Re/Os ratios, similar to sulphide ores from the Duluth, Sally Malay and Voisey Bay complexes. The Re-Os isotopic data from the disseminated and massive ores from the Xiangshan intrusion do not form a single isochron, as they have different initial Os ratios. The Hf and Os isotopic data suggest that the Xiangshan intrusion and associated Ni-Cu-Co mineralization were derived from crustally contaminated mantle melts. The geochemical data show a tholeiitic affinity and a strong suprasubduction zone signature with negative Nb, Sr, and Ti anomalies similar to N-MORB and E-MORB. We suggest that the mafic-ultramafic rocks and associated Ni-Cu mineralization of the Eastern Tianshan orogen formed in an Alaska-type subduction zone-arc setting. Some diagnostic features of ridge-trench interaction are present in the Chinese East Tianshan orogen (e.g. granites, adakites, high-Mg andesites, near-trench magmatism, Alaskan-type mafic-ultramafic complexes, high-temperature metamorphic belts that prograde rapidly from low-grade belts, and orogenic gold deposits). The above distinctive rock groups are probably related to the same thermal event, ridge subduction, as in the Cenozoic orogen of Alaska. We suggest that ridge subduction is the most plausible mechanism to provide the necessary heat. Ridge subduction provides an important promising model for understanding many aspects of the evolution of the Chinese

  15. Shielding properties of 80TeO2–5TiO2–(15−x) WO3–xAnOm glasses using WinXCom and MCNP5 code

    International Nuclear Information System (INIS)

    Dong, M.G.; El-Mallawany, R.; Sayyed, M.I.; Tekin, H.O.

    2017-01-01

    Gamma ray shielding properties of 80TeO 2 –5TiO 2 –(15−x) WO 3 –xA n O m glasses, where A n O m is Nb 2 O 5 = 0.01, 5, Nd 2 O 3 = 3, 5 and Er 2 O 3 = 5 mol% have been achieved. Shielding parameters; mass attenuation coefficients, half value layers, and macroscopic effective removal cross section for fast neutrons have been computed by using WinXCom program and MCNP5 Monte Carlo code. In addition, by using Geometric Progression method (G-P), exposure buildup factor values were also calculated. Variations of shielding parameters are discussed for the effect of REO addition into the glasses and photon energy. - Highlights: • The shielding properties of 80TeO 2 –5TiO 2 –(15−x) WO 3 –xA n O m glasses were evaluated. • WinXCom program and MCNP simulation codes were used in the calculations. • Good agreement was noticed between the WinXCom and MCNP5 code results.

  16. Efectividad de la logística del transporte aéreo de mercancías: Una aproximación multicriterio basada en el Proceso Analítico Sistémico (ANP)

    OpenAIRE

    Ponce Pérez, David; Larrodé Pellicer, Emilio; Moreno Jiménez, José María

    2012-01-01

    El objetivo principal de la presente Tesis Doctoral es crear y desarrollar un modelo de análisis que permita medir la alineación de los objetivos estratégicos del transporte aéreo de mercancías en la Situación Actual del sistema con dichos objetivos estratégicos en la Situación Ideal. Para ello, dicho modelo de análisis se basa en el apoyo metodológico que se obtiene de la técnica de análisis multicriterio Proceso de Análisis Sistémico (Anlytic Network Porcess, ANP) de T. Saaty (1996). Esta t...

  17. Síndrome da angústia respiratória aguda associada à varicela em paciente adulto: exemplo de suporte respiratório extracorpóreo em doenças endêmicas brasileiras

    Directory of Open Access Journals (Sweden)

    Marcela da Silva Mendes

    2014-12-01

    Full Text Available Descreveu-se aqui o caso de um homem de 30 anos de idade com quadro de varicela grave, hipoxemia refratária, vasculite do sistema nervoso central e insuficiência renal anúrica. Foi necessário transporte por ambulância com suporte respiratório extracorpóreo veno-venoso, sendo este utilizado até a recuperação do paciente. Discute-se o potencial uso de oxigenação por membrana extracorpórea em países em desenvolvimento para o controle de doenças comuns nestas áreas.

  18. Surface passivation of HgCdTe by CdZnTe and its characteristics

    Science.gov (United States)

    Lee, T. S.; Choi, K. K.; Jeoung, Y. T.; Kim, H. K.; Kim, J. M.; Kim, Y. H.; Chang, J. M.; Song, W. S.; Kim, S. U.; Park, M. J.; Lee, S. D.

    1997-06-01

    In this paper, we report the results of capacitance-voltage measurements conducted on several metal-insulator semiconductor (MIS) capacitors in which HgCdTe surfaces are treated with various surface etching and oxidation processes. CdZnTe passivation layers were deposited on HgCdTe surfaces by thermal evaporation after the surfaces were etched with 0.5-2.0% bromine in methanol solution, or thin oxide layers (tox ˜ few ten Å) were grown on the surfaces, in order to investigate effects of the surface treatments on the electrical properties of the surfaces, as determined from capacitance-voltage (C-V) measurements at 80K and 1 MHz. A negative flat band voltage has been observed for MIS capacitors fabricated after etching of HgCdTe surfaces with bromine in methanol solutions, which is reported to make the surface Te-rich. It is inferred that residual Te on the surface is a positive charge, Te4+. C-V characteristics for MIS capacitors fabricated on oxide surfaces grown by air-exposure and electrolytic process have shown large hysteresis effects, from which it is inferred that imperfect and electrically active oxide compounds and HgTe particles near the surface become slow interface states.

  19. Om te staak of nie te staak nie? Die sieninge van 'n aantal swart ...

    African Journals Online (AJOL)

    Erna Kinsey

    sig, is eerstens om ondersoek in te stel na 'n groep swart opvoeders se sieninge oor opvoeders se reg om te staak. Tweedens sal na die redes wat hierdie opvoeders aanvoer waarom hulle al aan stakings deel- geneem het of sal deelneem, gelet word. Derdens sal die redes waarom sommige opvoeders nie sal staak nie, ...

  20. The fingerprint of Te-rich and stoichiometric Bi2Te3 nanowires by Raman spectroscopy

    Science.gov (United States)

    Rodríguez-Fernández, Carlos; Manzano, Cristina V.; Romero, Aldo H.; Martín, Jaime; Martín-González, Marisol; Morais de Lima, Mauricio, Jr.; Cantarero, Andrés

    2016-02-01

    We unambiguously show that the signature of Te-rich bismuth telluride is the appearance of three new peaks in the Raman spectra of Bi2Te3, located at 88, 117 and 137 cm-1. For this purpose, we have grown stoichiometric Bi2Te3 nanowires as well as Te-rich nanowires. The absence of these peaks in stoichiometric nanowires, even in those with the smallest diameter, shows that they are not related to confinement effects or the lack of inversion symmetry, as stated in the literature, but to the existence of Te clusters. These Te clusters have been found in non-stoichiometric samples by high resolution electron microscopy, while they are absent in stoichiometric samples. The Raman spectra of the latter corresponds to the one for bulk Bi2Te3. The intensity of these Raman peaks are clearly correlated to the Te content. In order to ensure statistically meaningful results, we have investigated several regions from every sample.

  1. Cumulative effects of Te precipitates in CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Bolotnikov, A.E.; Camarda, G.S.; Carini, G.A.; Cui, Y.; Li, L.; James, R.B.

    2007-01-01

    High-quality radiation detector-grade CdZnTe material is free from large-scale defects, such as grain boundaries, twins, and large Te or Cd inclusions (>50 μm), although it usually contains high concentrations of uniformly distributed Te inclusions and precipitates, typically of ∼20-μm-diameter size or smaller. We address the effects of the small-size Te precipitates on charge collection in CZT detectors, the significance of which is not yet well characterized. The strong correlation that we earlier found between the high-resolution X-ray maps and IR images proved that even small Te precipitates can trap substantial fractions of charge from the electron cloud. In this work, we modeled the transport of an electron cloud across idealized CZT devices containing Te precipitates to demonstrate that their cumulative effect can explain the degradation of energy resolution and the detection efficiency losses observed in actual CZT devices. Due to lack of experimental data on how the Te precipitates interact with an electron cloud, we developed a simplified (phenomenological) model based on the geometrical aspects of the problem. Despite its simplicity, the model correctly reproduced many experimental facts and gave quantitative predictions on the extent to which the presence of Te precipitates and inclusions can be tolerated. The broadening of the electron cloud due to repulsion and diffusion is at the core of the problem, making even low concentrations of small precipitates important in the device's performance

  2. Age of the granitic magmatism and the W-Mo mineralization in skarns of the Seridó belt (NE Brazil) based on zircon U-Pb (SHRIMP) and molybdenite Re-Os dating

    Science.gov (United States)

    Hollanda, Maria Helena B. M. de; Souza Neto, João A.; Archanjo, Carlos J.; Stein, Holly; Maia, Ana C. S.

    2017-11-01

    Over five hundred W-Mo skarns have been reported in the Neoproterozoic Seridó belt in the northeastern Brazil. The origin of these mineralizations has been attributed to metasomatic reactions occuring after the infiltration of hydrothermal fluids that are mostly derived from the plutonic magmatic activity that ranged between approximately 600 and 525 Ma. Here we date molybdenite using N-TIMS on Re-Os analysis of three major scheelite deposits (Brejuí, Bonfim and Bodó) hosted in the skarn horizons of the metasedimentary sequence. Molybdenite is an integral part of the mineralizations that include scheelite in skarns and, in the Bonfim deposit, gold concentrate in late brittle faults. The Re-Os ages are 554 ± 2 Ma (Brejuí), 524 ± 2 Ma (Bonfim) and 510 ± 2 Ma (Bodó). The age of the Brejuí molybdenite, however, appears to be anomalous based on the local geology of the deposit, which is located next to the contact of a batholith dated ca. 575 Ma. In turn, the Bonfim molybdenite yields similar ages in replicated samples with variable high Re contents. New U-Pb SHRIMP ages of four biotite (leuco)granite plutons vary from 577 ± 5 Ma to 526 ± 8 Ma, which overlap with molybdenite crystallization. These results indicate a close connection between the W-Mo mineralizations and the plutonic activity that intruded the belt after the peak HT/LP metamorphism. The latest pulses of felsic magmatism, which were contemporaneous with the emplacement of Be-Ta-Nb-Li pegmatites, therefore constitute a potential guide in the Seridó belt for prospective W-Mo deposits.

  3. Transmissible venereal tumor in the palpebral conjunctiva of a dog: case reportTumor venéreo transmissível na conjuntiva palpebral de um cão – relato de caso

    Directory of Open Access Journals (Sweden)

    Luciane de Albuquerque

    2011-08-01

    Full Text Available The transmissible venereal tumor (TVT is a contagious neoplasm that occurs in sexually mature dogs, usually transmitted by coitus. This tumor normally affects the genital mucosa and is rarely found in any other part of the body. A case of transmissible venereal tumor in the palpebral conjunctiva of a 3-year old, crossbreed, male dog with a history of an abnormal mass in the right eye was presented. Ophthalmic examination revealed a mass originated from the lower eyelid conjunctiva of the right eye. No other ocular abnormalities were detected. Cytological examination was carried out and the diagnosis was TVT. The dog was treated with lyophilized vincristine sulphate intravenously, once a week, for four weeks. Despite the atypical clinical presentation, the response to chemotherapy with vincristine was excellent leading to complete regression of the neoplasm and no relapse after a year.O tumor venéreo transmissível (TVT é uma neoplasia contagiosa que ocorre em cães sexualmente maduros, sendo geralmente transmitido pelo coito. A neoplasia normalmente afeta a mucosa genital e é raramente encontrada em outras partes do corpo. Apresentamos um caso de tumor venéreo transmissível na conjuntiva palpebral de um cão macho, sem raça definida, com três anos de idade e histórico de presença de uma massa na conjuntiva palpebral inferior do olho direito. Não foram detectadas outras alterações oculares. O diagnóstico citológico da massa foi TVT. O cão foi tratado com sulfato de vincristina por via intravenosa, uma vez por semana, durante quatro semanas. Embora a apresentação do caso seja atípica, a resposta à quimioterapia foi excelente, levando a regressão completa da neoplasia, sem recorrência após um ano.

  4. Study of Te Inclusion and Related Point Defects in THM-Growth CdMnTe Crystal

    Science.gov (United States)

    Mao, Yifei; Zhang, Jijun; Min, Jiahua; Liang, Xiaoyan; Huang, Jian; Tang, Ke; Ling, Liwen; Li, Ming; Zhang, Ying; Wang, Linjun

    2018-02-01

    This study establishes a model for describing the interaction between Te inclusions, dislocations and point defects in CdMnTe crystals. The role of the complex environment surrounding the formation of Te inclusions was analyzed. Images of Te inclusions captured by scanning electron microscope and infrared microscope were used to observe the morphology of Te inclusions. The morphology of Te inclusions is discussed in light of crystallography, from the crystal growth temperature at 900°C to the melting temperature of Te inclusions using the traveling heater method. The dislocation nets around Te inclusions were calculated by counting lattice mismatches between the Te inclusions and the bulk CdMnTe at 470°C. The point defects of Te antisites were found to be gathered around Te inclusions, with dislocation climb during the cooling phase of crystal growth from 470°C to room temperature. The Te inclusions, dislocation nets and surrounding point defects are considered to be an entirety for evaluating the effect of Te inclusions on CdMnTe detector performance, and an effective mobility-lifetime product (μτ) was obtained.

  5. Fabrication of Te and Te-Au Nanowires-Based Carbon Fiber Fabrics for Antibacterial Applications

    Directory of Open Access Journals (Sweden)

    Ting-Mao Chou

    2016-02-01

    Full Text Available Pathogenic bacteria that give rise to diseases every year remain a major health concern. In recent years, tellurium-based nanomaterials have been approved as new and efficient antibacterial agents. In this paper, we developed the approach to directly grow tellurium nanowires (Te NWs onto commercial carbon fiber fabrics and demonstrated their antibacterial activity. Those Te NWs can serve as templates and reducing agents for gold nanoparticles (Au NPs to deposit. Three different Te-Au NWs with varied concentration of Au NPs were synthesized and showed superior antibacterial activity and biocompability. These results indicate that the as-prepared carbon fiber fabrics with Te and Te-Au NWs can become antimicrobial clothing products in the near future.

  6. Improved structural and electrical properties in native Sb2Te3/GexSb2Te3+x van der Waals superlattices due to intermixing mitigation

    NARCIS (Netherlands)

    Cecchi, Stefano; Zallo, Eugenio; Momand, Jamo; Wang, Ruining; Kooi, Bart J.; Verheijen, Marcel A.; Calarco, Raffaella

    Superlattices made of Sb2Te3/GeTe phase change materials have demonstrated outstanding performance with respect to GeSbTe alloys in memory applications. Recently, epitaxial Sb2Te3/GeTe superlattices were found to feature GexSb2Te3+x blocks as a result of intermixing between constituting layers.

  7. Improved structural and electrical properties in native Sb2Te3/GexSb2Te3+x van der Waals superlattices due to intermixing mitigation

    NARCIS (Netherlands)

    Cecchi, S.; Zallo, E.; Momand, J.; Wang, R.; Kooi, B.J.; Verheijen, M.A.; Calarco, R.

    Superlattices made of Sb2Te3/GeTe phase change materials have demonstrated outstanding performance with respect to GeSbTe alloys in memory applications. Recently, epitaxial Sb2Te3/GeTe superlattices were found to feature GexSb2Te3+x blocks as a result of intermixing between constituting layers. Here

  8. Design principles for HgTe based topological insulator devices

    Science.gov (United States)

    Sengupta, Parijat; Kubis, Tillmann; Tan, Yaohua; Povolotskyi, Michael; Klimeck, Gerhard

    2013-07-01

    The topological insulator properties of CdTe/HgTe/CdTe quantum wells are theoretically studied. The CdTe/HgTe/CdTe quantum well behaves as a topological insulator beyond a critical well width dimension. It is shown that if the barrier (CdTe) and well-region (HgTe) are altered by replacing them with the alloy CdxHg1-xTe of various stoichiometries, the critical width can be changed. The critical quantum well width is shown to depend on temperature, applied stress, growth directions, and external electric fields. Based on these results, a novel device concept is proposed that allows to switch between a normal semiconducting and topological insulator state through application of moderate external electric fields.

  9. Investigations on the system Te/O/Br

    International Nuclear Information System (INIS)

    Oppermann, H.; Kunze, G.; Wolf, E.; Titov, V.A.; Kokovin, G.A.

    1978-01-01

    The melting point diagram of the system TeBr 4 -TeO 2 was obtained by total pressure measurements and DTA measurements. A congruent melting composition Te 6 O 11 Br 2 exists, the melting point is 570 0 C. The enthalpy of formation and the standard entropy of the species TeOBr 2 ,g was derived from measurements of the total pressure over Te 6 O 11 Br 2 /TeBr 4 and from the transport behaviour of the TeO 2 with Br 2 . From the decomposition-pressure measurements over Te 6 O 11 Br 2 /TeO 2 follow the partial pressures. The enthalpy of formation ΔH 0 (Te 6 O 11 Br 2 ,f,298) -453.5 kcal/Mol was obtained from the enthalpy of solution. The transport-behaviour of TeO 2 with HBr, TeBr 4 and Br 2 and that of Te 6 O 11 Br 2 is clear with the thermodynamic data of TeOBr 2 . (author)

  10. Review of CdTe medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Entine, G; Garcia, D A; Tow, D E

    1977-02-01

    CdTe sensors are now being used in several areas of nuclear medicine. CdTe probe technics, originally developed to study dental pathology in dog models, are being used clinically to diagnose venous thrombosis of the legs and to detect occult dental infections in patients scheduled for prosthetic cardiovascular and orthopedic surgery. Similar instrumentation is in use in animal research of myocardial infarction and synthetic tooth substitutes. Transmission technics have also been developed to diagnose pulmonary edema and to measure bone mineral changes in space flight. Investigations are also underway in the use of linear or two-dimensional arrays of CdTe gamma sensors for medical imaging. Economic considerations have slowed this work, but the technology appears to be available. Development of photoconductive CdTe X-ray detectors for scintigraphic scanners has also begun. Rapid detector improvement will be needed for success in this field, but the potential usefulness is very great. Together, the present application results are encouraging and wide use of CdTe detectors should occur within only a few years.

  11. Research into the electrical property variation of undoped CdTe and ZnTe crystals grown under Te-rich conditions

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yadong, E-mail: xyd220@nwpu.edu.cn; Liu, Hang; He, Yihui; Yang, Rui; Luo, Lin; Jie, Wanqi

    2014-11-05

    Highlights: • Conductivity type and resistivity of undoped Te-rich ZnTe and CdTe are different. • Te{sub i} and V{sub Zn} as the dominant defects account for the p-type low resistivity ZnTe. • Te{sub Cd} as the principle defect leading to the light n-type high resistivity CdTe. • DAP and eA peaks dominate the luminescence with their intensities anti-correlated. - Abstract: Both undoped ZnTe and CdTe bulk single crystals are grown under Te-saturated conditions from the solution and melt, respectively. To give an insight into the variation of the electrical properties, the defects structures in both tellurides are discussed. According to the actual growth velocities and the entire cooling history, tellurium interstitials (Te{sub i}) and Zinc vacancies (V{sub Zn}) are proposed as the dominant grown-in defects, account for the low resistivity of p-type ZnTe. However, relatively high pulling rates and slow cooling-down processes result in tellurium anti-sites (Te{sub Cd}) as the principle grown-in defects, leading to the high resistivity of light n-type CdTe. Further low-temperature (8.6 K) photoluminescence spectra of both tellurides are obtained. The donor–acceptor pair (DAP) and recombination of free electron to neutral acceptor (eA) dominate the luminescence, however, with their intensities are anti-correlated. eA is superior to DAP in undoped Te-rich ZnTe, suggests a high concentration of Te{sub i} or V{sub Zn}. On the contrary, DAP is the principal emission for undoped Te-rich CdTe. In addition, V-line is clearly identified in undoped Te-rich ZnTe, which possibly associated with V{sub Zn} or close Frenkel pair V{sub Zn}–Zn{sub i}.

  12. "Kia whakatomuri te haere whakamua": "I Walk Backwards into the Future with My Eyes Fixed on My Past"

    Science.gov (United States)

    Rameka, Lesley

    2016-01-01

    This "whakatauki" or "proverb" speaks to Maori perspectives of time, where the past, the present and the future are viewed as intertwined, and life as a continuous cosmic process. Within this continuous cosmic movement, time has no restrictions--it is both past and present. The past is central to and shapes both present and…

  13. Anomalous phase change characteristics in Fe-Te materials

    International Nuclear Information System (INIS)

    Fu, X. T.; Song, W. D.; Ji, R.; Ho, H. W.; Wang, L.; Hong, M. H.

    2012-01-01

    Phase change materials have become significantly attractive due to its unique characteristics for its extensive applications. In this paper, a kind of phase change material, which consists of Fe and Te components, is developed. The crystallization temperature of the Fe-Te materials is 180 deg. C for Fe 1.19 Te and can be adjusted by the Fe/Te ratio. High-speed phase change in the Fe-Te materials has been demonstrated by nanosecond laser irradiation. Comparing to conventional phase change materials, the Fe-Te materials exhibit an anomalous optical property that has higher reflectivity at amorphous than crystalline state, which is useful for data storage design.

  14. Simple one-pot aqueous synthesis of CdHgTe nanocrystals using sodium tellurite as the Te source

    International Nuclear Information System (INIS)

    Shen, Zhitao; Luo, Chunhua; Huang, Rong; Wang, Yiting; Peng, Hui; Travas-sejdic, Jadranka

    2014-01-01

    In this work, we systematically investigated the one-pot aqueous synthesis conditions of CdHgTe nanocrystals (NCs) using sodium tellurite (Na 2 TeO 3 ) as the Te source, and found that the added content of Hg 2+ and the initial pH value of reaction solutions significantly affected the photoluminescence quantum yield (PL QY) of alloyed CdHgTe NCs. When the concentration of Cd was 1.0 mmol L −1 , the mole ratio of Cd/Te/Hg/MPA was 1:0.5:0.05:2.4, and the initial pH value of the reaction solution was about 8.78, the PL QY of as-prepared CdHgTe NCs was up to 45%. Characterization by HRTEM and XRD confirmed the crystalline nature of CdHgTe NCs. Compared to other synthetic approaches of CdHgTe NCs, our experimental results indicate that Na 2 TeO 3 could be an attractive alternative Te source to directly synthesize CdHgTe NCs in aqueous media. - Highlights: • A one-pot method was developed for the synthesis of highly luminescent CdHgTe nanocrystals (NCs). • Sodium tellurite was used as the Te source. • The quantum yield reached up to 45%. • The experimental conditions were optimized and the prepared CdHgTe NCs were characterized

  15. TeV gamma-ray astronomy

    International Nuclear Information System (INIS)

    Cui Wei

    2009-01-01

    The field of ground-based gamma-ray astronomy has enjoyed rapid growth in recent years. As an increasing number of sources are detected at TeV energies, the field has matured and become a viable branch of modern astronomy. Lying at the uppermost end of the electromagnetic rainbow, TeV photons are always preciously few in number but carry essential information about the particle acceleration and radiative processes involved in extreme astronomical settings. Together with observations at longer wavelengths, TeV gamma-ray observations have drastically improved our view of the universe. In this review, we briefly describe recent progress in the field. We will conclude by providing a personal perspective on the future of the field, in particular, on the significant roles that China could play in advancing this young but exciting field. (invited reviews)

  16. Delineation of phase fields at the Te-rich end of the Ru Te binary system

    Science.gov (United States)

    Ali (Basu), M.; Bharadwaj, S. R.; Das, D.

    2005-04-01

    The tellurium rich side of the ruthenium-tellurium binary system was studied by differential thermal analysis. To avoid reported problems of Te loss by evaporation and reactive interference of Te to the thermocouples of the thermal analyzer, the present study made use of specially designed sealed quartz capsules as DTA containers. The thermal analyses were carried out over the compositional range of 0.66 ⩽ xTe ⩽ 1.00 with the help of SETARAM TG/DTA and other indigenously built thermal analyzers available in this laboratory. The thermal data generated for fifteen different compositions were interpreted for the nature of phase transitions occurring at their characteristic temperatures. The Ru-Te binary system was found to have a eutectic transformation at 444 °C at a composition of xTe = 0.918 and a monotectic transformation at 447 °C at a composition of xTe = 0.700. Up to 6 at.% Ru is soluble in Te at about 440 °C.

  17. TeV. The dream energy scale

    International Nuclear Information System (INIS)

    Murayama, Hitoshi

    2006-01-01

    In this talk, I'd like to explain why the TeV, 1,000,000,000,00 electron volt, is a particularly interesting energy scale in physics. I being recapitulating what particle physics is all about, citing two big questions: what the Universe is made of, and Einstein's dream of unification. TeV energy appears to be relevant to both questions, suggesting rich and complex physics at this energy. I outline how two facilities, LHC and ILC, will work together with reveal what is going on at this exciting energy scale. (author)

  18. PbSnTe injection lasers

    International Nuclear Information System (INIS)

    Oron, M.

    1982-03-01

    Carrier confined homostructure PbSnTe lasers were developed and investigated. In this laser structure good electrical and optical confinement can be achieved by a suitable carrier concentration profile. The advantage of these lasers over PbSnTe heterostructure lasers is the perfect lattice matching between the various layers of the structure. The desired carrier concentration profile was achieved by the growth of several epitaxial layers by the LPE method on a suitable substrate. The performance of these lasers was compared with that of previous homostructure and double heterostructure lasers. (H.K.)

  19. Thermodynamic characterization of Ni3TeO6, Ni2Te3O8 and NiTe2O5

    Science.gov (United States)

    Dawar, Rimpi; Babu, R.; Ananthasivan, K.; Anthonysamy, S.

    2017-09-01

    Measurement of vapour pressure of TeO2(g) over the biphasic mixture Ni3TeO6 (s) + NiO(s) in the temperature range 1143-1272 K was carried out using transpiration-thermogravimetric technique (TTG). Gibbs energy of formation of Ni3TeO6 was obtained from the temperature dependence of vapour pressure of TeO2 (g) generated by the incongruent vapourisation reaction, Ni3TeO6 (s) → NiO(s) + TeO2 (g) + 1/2 O2 in the temperature range 1143-1272 K. An isoperibol type drop calorimeter was used to measure the enthalpy increments of Ni3TeO6, Ni2Te3O8 and NiTe2O5. Thermodynamic functions viz., heat capacity, entropy and Gibbs energy functions of these compounds were derived from the experimentally measured enthalpy increment values. Third-law analysis was carried out to ascertain absence of temperature dependent systematic errors in the measurement of vapour pressure of TeO2 (g). A value of -1265.1 ± 1.5 kJ mol-1 was obtained for Δ Hf,298K o (Ni3TeO6) using third-law analysis.

  20. Manufacturing Te/PEDOT Films for Thermoelectric Applications.

    Science.gov (United States)

    Culebras, Mario; Igual-Muñoz, Ana María; Rodríguez-Fernández, Carlos; Gómez-Gómez, María Isabel; Gómez, Clara; Cantarero, Andrés

    2017-06-21

    In this work, flexible Te films have been synthesized by electrochemical deposition using PEDOT [poly(3,4-ethylenedioxythiophene)] nanofilms as working electrodes. The Te electrodeposition time was varied to find the best thermoelectric properties of the Te/PEDOT double layers. To show the high quality of the Te films grown on PEDOT, the samples were analyzed by Raman spectroscopy, showing the three Raman active modes of Te: E 1 , A 1 , and E 2 . The X-ray diffraction spectra also confirmed the presence of crystalline Te on top of the PEDOT films. The morphology of the Te/PEDOT films was studied using scanning electron microscopy, showing a homogeneous distribution of Te along the film. Also an atomic force microscope was used to analyze the quality of the Te surface. Finally, the electrical conductivity and the Seebeck coefficient of the Te/PEDOT films were measured as a function of the Te deposition time. The films showed an excellent thermoelectric behavior, giving a maximum power factor of about 320 ± 16 μW m -1 K -2 after 2.5 h of Te electrochemical deposition, a value larger than that reported for thin films of Te. Qualitative arguments to explain this behavior are given in the discussion.

  1. Reduction in thermal conductivity of BiSbTe lump

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Kaleem [King Saud University, Sustainable Energy Technologies Center, College of Engineering, PO Box 800, Riyadh (Saudi Arabia); Wan, C. [Tsinghua University, State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Beijing (China); Al-Eshaikh, M.A.; Kadachi, A.N. [King Saud University, Research Center, College of Engineering, PO Box 800, Riyadh (Saudi Arabia)

    2017-03-15

    In this work, systematic investigations on the thermal conductivities of BiSbTe lump, microstructured pristine BiSbTe bulk and single wall carbon nanotubes (SWCNTs)/BiSbTe bulk nanocomposites were performed. BiSbTe lumps were crushed to form a coarse powder (200 μm) and effect of particle size reduction on the effective thermal conductivity of BiSbTe (200 μm) bulk were analyzed. For further reduction in the conductivity, a two pronged strategy has been employed. First, additional refinement of BiSbTe (200 μm) were performed through ball milling in an inert environment. Second, SWCNTs in 0.75, and 1.0 vol% were distributed uniformly in the fine BiSbTe ball milled powder. The results showed that the effective thermal conductivities decrease with the reduction in the particle size from lump to BiSbTe (200 μm) bulk as well as with the addition of SWCNTs accompanied by further refinement of BiSbTe particles. The significant reduction in thermal conductivities of the lump was achieved for pure BiSbTe (200 μm) bulk and 0.75 vol% of SWCNTs/BiSbTe composite. This can be ascribed to the enhanced phonon scattering by the grain boundaries between the nanostructured BiSbTe particles as well as the interfaces between BiSbTe and the low dimensional carbon nanotubes. (orig.)

  2. Phase diagram of SnTe-CdSe cross-section of SnTe+CdSe reversible SnSe+CdTe ternary reciprocal system

    International Nuclear Information System (INIS)

    Dubrovin, I.V.; Budennaya, L.D.; Mizetskaya, I.B.; Sharkina, Eh.V.

    1986-01-01

    Phase equilibrium diagram of SnTe-CdSe cross-section of Sn, Cd long Te, Se ternary reciprocal system is investigated using the methods of differential thermal, X-ray phase, and microstructural analyses. Maximum length of solid solutions on the base of SnTe corresponds to approximately 14 mol.% at 1050 K and approximately 3 mol.% of CdSe at 670 K. Region of solid solutions on the base of CdSe corresponds to less than 1 mol.% of SnTe at room temperature. SnTe-CdSe cross-section is not a quasibinar one. Equilibrium is shifted to the left in the SnTe+CdSe reversible SnSe+CdTe reciprocal system

  3. X-ray electron spectra of chalcogenide glasses and polycrystalline alloys of Ge-Te and As-Te systems

    International Nuclear Information System (INIS)

    Panus, V.R.

    1990-01-01

    Comparative investigation into structures of crystals and glasses in Ge-Te and As-Te two-component systems was conducted. Analysis of x-ray electron spectra of Ge-Te and As-Te systems indicates, that processes of dissociation-association resulting in formation of new structure units occur in telluride melts at synthesis temperatures. Structural chemical composition of binary glass-like alloys of Ge-Te and As-Te systems differs essentially from the one that corresponds to fusibility equilibrium curve. Oxygen doping into tellurium-base glasses results mainly in occurence of structures forecasted due to thermochemical calculation

  4. New Zealand Perspectives on Early Childhood Education: Naku Te Rourou Nau Te Rourou Ka Ora Ai Te Iwi

    Science.gov (United States)

    Tesar, Marek

    2016-01-01

    This special issue focuses on histories, pedagogies, policies, philosophies and alternative perspectives in early childhood education. "Te Whariki" is heralded as the first bicultural curriculum not only in New Zealand, but in the world. Its importance is reflected in national and international research and early childhood discourses.…

  5. Strong coupling and polariton lasing in Te based microcavities embedding (Cd,Zn)Te quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Rousset, J.-G., E-mail: j-g.rousset@fuw.edu.pl; Piętka, B.; Król, M.; Mirek, R.; Lekenta, K.; Szczytko, J.; Borysiuk, J.; Suffczyński, J.; Kazimierczuk, T.; Goryca, M.; Smoleński, T.; Kossacki, P.; Nawrocki, M.; Pacuski, W. [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, PL-02-093 Warszawa (Poland)

    2015-11-16

    We report on properties of an optical microcavity based on (Cd,Zn,Mg)Te layers and embedding (Cd,Zn)Te quantum wells. The key point of the structure design is the lattice matching of the whole structure to MgTe, which eliminates the internal strain and allows one to embed an arbitrary number of unstrained quantum wells in the microcavity. We evidence the strong light-matter coupling regime already for the structure containing a single quantum well. Embedding four unstrained quantum wells results in further enhancement of the exciton-photon coupling and the polariton lasing in the strong coupling regime.

  6. Plattelandimpuls : leren door gewoon te dóen

    NARCIS (Netherlands)

    Noorduyn, L.

    2008-01-01

    Plattelandsondernemers die hun activiteiten verbreden, vergeten nogal eens serieuze aandacht te besteden aan de vermarkting van hun product. Met het project PlattelandImpuls hebben ondernemers hun vaardigheden op dat vlak kunnen verbeteren door te werken met product-marktcombinaties.

  7. ??????????? ????????? ???????????? ???????????? NH4X (?=??,?1) ??? ??????????? CdxHgi-xTe ??????? ???????? ???????????? ???????

    OpenAIRE

    ??????, ?. ?.; ?????????, ?. ?.; ???????, ?. ?.; ?????????, ?. ?.; ?????????, ?. ?.

    2004-01-01

    ?? ?????? ??????????? ?????????? ???????????? ?????? ??????? ???? ??????? CdxHgi_xTe-Hg-NH4Br ??? ??????? ?????? Hg ? ????????? ?????????? 560-860? ? ??????????? ?????? ?? = 103-=-105 ?? ????????? ????????, ??? ??????? ???????? ????? ? ??????????????? ??????, ????? ? ?????? - CdBr2, Hg, ??2. ??? ????????? ??????? ??????? ???????????? CdxHgi_xTe ??????? ? = 0.2; 0.3; 0.4 ?? ????????? ??? ??? ? ??? ?????????? ??????? ???????? ??????? (??? ?????? ?????? ????? ? ???????) ????????? ??????????? ???...

  8. TeSLA workshop betrouwbaar toetsen op afstand

    NARCIS (Netherlands)

    Brouns, Francis; Janssen, José

    2017-01-01

    Presentatie ten behoeve van workshop betrouwbaar toetsen op afstand voor docenten van de Open Universiteit Nederland betrokken in de derde TeSLA pilot. Topics: toetsfraude, toetsdesign, technologie voor authenticatie en verificatie van auteurschap, TeSLA instrumenten.

  9. TeSLA e-assessment workshop pilot 2

    OpenAIRE

    Janssen, José

    2017-01-01

    Presentatie ten behoeve van de e-assessment workshop voor docenten van de Open Universiteit Nederland betrokken in de tweede TeSLA pilot. Topics: toetsfraude, toetsdesign, technologie voor authenticatie en verificatie van auteurschap, TeSLA instrument.

  10. De iep is weer te vertrouwen

    NARCIS (Netherlands)

    Hiemstra, J.A.; Beintema, N.

    2012-01-01

    De iep is door de iepziekte grotendeels uit Europa verdwenen. Mede dankzij Wagenings onderzoek zijn er nu resistente rassen op de markt. Wat nog ontbreekt is het vertrouwen van beheerders om de karakteristieke boom weer aan te planten. ‘Iepen waren synoniem met ellende.’

  11. TeV scale singlet dark matter

    International Nuclear Information System (INIS)

    Ponton, Eduardo; Randall, Lisa

    2009-01-01

    It is well known that stable weak scale particles are viable dark matter candidates since the annihilation cross section is naturally about the right magnitude to leave the correct thermal residual abundance. Many dark matter searches have focused on relatively light dark matter consistent with weak couplings to the Standard Model. However, in a strongly coupled theory, or even if the coupling is just a few times bigger than the Standard Model couplings, dark matter can have TeV-scale mass with the correct thermal relic abundance. Here we consider neutral TeV-mass scalar dark matter, its necessary interactions, and potential signals. We consider signals both with and without higher-dimension operators generated by strong coupling at the TeV scale, as might happen for example in an RS scenario. We find some potential for detection in high energy photons that depends on the dark matter distribution. Detection in positrons at lower energies, such as those PAMELA probes, would be difficult though a higher energy positron signal could in principle be detectable over background. However, a light dark matter particle with higher-dimensional interactions consistent with a TeV cutoff can in principle match PAMELA data.

  12. High performance p-i-n CdTe and CdZnTe detectors

    CERN Document Server

    Khusainov, A K; Ilves, A G; Morozov, V F; Pustovoit, A K; Arlt, R D

    1999-01-01

    A breakthrough in the performance of p-i-n CdTe and CdZnTe detectors is reported. The detector stability has been significantly improved, allowing their use in precise gamma and XRF applications. Detectors with energy resolution close to Si and Ge were produced operating with only -30--35 deg. C cooling (by a Peltier cooler of 15x15x10 mm size and a consumed power less than 5 W). Presently detectors with volume of up to 300 mm sup 3 are available. In terms of photoelectric effect efficiency it corresponds to HPGe detectors with volumes of about 1.5 cm sup 3. The possibilities of further improvement of CdTe and CdZnTe detector characteristics are discussed in this paper.

  13. CdTe and Cd1-xZnxTe for nuclear detectors: facts and fictions

    International Nuclear Information System (INIS)

    Fougeres, P.; Siffert, P.; Hageali, M.; Koebel, J.M.; Regal, R.

    1999-01-01

    Both CdTe and Cd 1-x Zn x Te (CZT) can be considered from their physical properties as very good materials for room temperature X- and γ-rays detection. However, despite years of intense material research, no significant advance has been made to help one to choose between both semiconductors. This paper reviews a few facts about CdTe and CZT to attempt to draw a real comparison between both. THM-CdTe and HPB-CZT have been grown and characterized in Strasbourg. Crystal growth, alloying effects, transport properties and defects are reviewed on the basis of our results and the published ones. The results show that it is still very difficult to claim which one is the best

  14. Local atomic interdiffusion in CdTe/HgCdTe multilayered structures

    International Nuclear Information System (INIS)

    Kim, Y.; Ourmazd, A.; Feldman, R.D.; Rentschler, J.A.; Taylor, D.W.; Austin, R.F.

    1989-01-01

    The authors combine chemical lattice imaging with digital pattern recognition to study atomic interdiffusion at individual CdTe/HgCdTe interfaces in multi-quantum well structures. In this way they obtain quantitative composition profiles for as grown samples, and investigate their development as a function of annealing temperature. The authors' results indicate that interdiffusion depends on the position of the quantum well with respect to the surface, beginning first at quantum wells close to the surface, and proceeding towards the substrate. The authors' approach allows the quantification of interdiffusion as a function of time, temperature, and distance from the surface. The implications of these results for the stability of CdTe/HgCdTe structures, and the interpretation of X-ray data are discussed

  15. Speaking the Unspoken: Racism, Sport and Maori

    Directory of Open Access Journals (Sweden)

    Holly Raima Hippolite

    2010-08-01

    Full Text Available In this paper, we argue that the intersection of two key ideologies – New Zealand’s purported history of good race relations, and the positive contribution sport is believed to make to racial equality – has created an environment in which it is difficult to talk about, let alone discuss constructively, Māori experiences of racism in the sport context. Our aim is to put the issue on the agenda by engaging with 10 experienced Māori sport participants, coaches and administrators whose experiences demonstrate the existence of, and pain caused by, cultural and institutional racism in New Zealand sport. In this aim, we do not seek to hide behind a veil of neutrality or objectivity. Rather, following a kaupapa Māori research approach, our interest is in bringing to light the voices, frustrations and concerns of Māori in order to contribute to a much-needed conversation.

  16. Design and construction of a mode converter from TE10(rectangular) to TE11(circular)

    International Nuclear Information System (INIS)

    Tubbing, B.J.D.

    1984-08-01

    The design and manufacturing of a wavelength mode converter from the TE 10 (rectangular) mode in oversized rectangular to the TE 11 (circular) mode in oversized circular waveguide is described. A differential equation for the cross-sectional shape of the converter was solved numerically. A stainless-steel mandrel was produced on a numerically controlled milling machine. Sixteen converters were produced by means of electroforming on one mandrel. (Auth.)

  17. La medición de la nicotina como marcador aéreo del humo ambiental de tabaco Nicotine measurement as an airborne marker of environmental tobacco smoke

    Directory of Open Access Journals (Sweden)

    M. Nebot

    2003-01-01

    Full Text Available Introducción: Numerosos estudios científicos han demostrado la asociación del humo ambiental de tabaco (HAT con múltiples riesgos para la salud. Sin embargo, la medición de la exposición a este humo ha sido poco precisa hasta hace pocos años. En este artículo se revisan diversos estudios que han utilizado la nicotina como marcador aéreo del HAT. Métodos: Se revisan los diferentes métodos utilizados en la medición de la exposición al HAT, con especial énfasis en el uso de la nicotina como marcador aéreo de su presencia, comparando sus características con las de los demás marcadores y analizando los resultados encontrados en diferentes estudios en los que se ha medido la concentración de nicotina en muestras de aire en espacios públicos y en el medio laboral. Resultados: La nicotina reúne las características deseables de los marcadores del HAT, y los resultados de diversos estudios en los que se ha utilizado muestran un amplio rango de valores. Así, en cafeterías y restaurantes la concentración de nicotina oscila entre 0,52 y 47,86 μg/m³, mientras que en los lugares de trabajo sin restricciones relativas al tabaco, las concentraciones varían entre 3,4 y 14 μg/m³, y en aquellos con prohibición total de fumar, la concentración oscila entre 0,09 y 0,7 μg/m³. Los lugares de ocio nocturno son los lugares donde las concentraciones son más elevadas, llegando a alcanzar valores que superan los 65 μg/m³. Discusión: El uso de la nicotina como marcador aéreo permite medir de manera objetiva la exposición al HAT. Los valores obtenidos en los estudios que utilizan este marcador muestran que en los lugares con restricciones o prohibiciones relativas al consumo de tabaco la exposición al HAT es mucho menor que en los en los que no hay ningún tipo de regulación.Introduction: Several studies have demonstrated the relationship between environmental tobacco smoke (ETS and different types of health risk. Despite this evidence

  18. Effect of Te atmosphere annealing on the properties of CdZnTe single crystals

    International Nuclear Information System (INIS)

    Yu Pengfei; Jie Wanqi; Wang Tao

    2011-01-01

    Low-resistivity CdZnTe:In (CZT:In) single crystals were annealed under Te atmosphere according to the behaviors of deep-donor Te antisite. The results indicated that the star-like Cd inclusions were completely eliminated after 120 h annealing. Meanwhile, the resistivity is greatly enhanced. The resistivity of the slice annealed after 240 h was achieved as high as 1.8x10 11 Ω cm, five orders of magnitude higher than that of as-grown slice. It suggested that the deep-donor level Te antisites were successfully introduced to pin the Fermi level at the mid band-gap position. The IR transmittances of the slices were also improved, which increased as the annealing time increased. PL measurement revealed that the (D 0 ,X) peak representing high quality of CZT crystal appeared. It can be concluded that the quality of CZT crystals is obviously improved after annealing under Te atmosphere. - Highlights: → High resistivity is due to deep-donor level Te Cd . → The resistivity achieved was as high as 1.8x10 11 Ω cm. → Star-like inclusions are Cd inclusions. → (D 0 ,X) peak represents the improvement of the crystal quality.

  19. Fluctuations in induced charge introduced by Te inclusions within CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Bale, Derek S.

    2010-01-01

    Recently, homogenization theory based on a multiple-scale perturbation of the electron transport equation has been used to derive a mathematical framework for modeling the excess charge lost to Te inclusions within radiation detectors based on semi-insulating cadmium zinc telluride (CdZnTe). In that theory, the heterogeneous material is mathematically replaced by a homogenized CdZnTe crystal whose effective electron attenuation length incorporates the additional uniform electron trapping caused by the inclusions. In this paper, the homogenization theory is extended to incorporate fluctuations in the induced charge (i.e., charge collection nonuniformities) introduced by the random position and size distributions of a noncorrelated population of small (i.e, <20 μm) Te inclusions. Analysis of the effective parameters derived within the homogenized framework is used to develop a probability distribution of effective electron attenuation lengths, and therefore effective mobility-lifetime products, as a function of both the position and size distribution of Te inclusions. Example distributions are detailed for the case of an exponential size distribution at various number densities. Further, it is demonstrated that the inclusion-induced material nonuniformities derived in this paper can be numerically sampled efficiently, making them applicable to Monte Carlo device simulation of realistic CdZnTe detectors. Simulated charge induction maps and pulse-height spectra are presented and compared to recently published measurements.

  20. Molecular beam epitaxy of iodine-doped CdTe and (CdMg)Te

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, F.; Waag, A.; Litz, Th.; Scholl, S.; Schmitt, M.; Landwehr, G. (Physikalisches Inst. der Univ. Wuerzburg (Germany)); Bilger, G. (Zentrum fuer Sonnenenergie und Wasserstofforschung, Stuttgart (Germany))

    1994-08-01

    The n-type doping of CdTe and (CdMg)Te by the use of the solid dopant source material ZnI[sub 2] is reported. Doping levels as high as 7x10[sup 18] cm[sup -3] have been obtained in CdTe with carrier mobilities around 500 cm[sup 2]/V[center dot]s at room temperature. For a dopant incorporation higher than 1x10[sup 19] cm[sup -3] the free carrier concentration decreases, indicating the onset of a compensation mechanism, which is observed in the case of chlorine and bromine doping, too. Preliminary experiments show that with increasing Mg concentration the free carrier concentration decreases. Nevertheless, CdMgTe with a magnesium concentration x=0.37 (band gap 2.2 eV at room temperature) can be doped up to 2x10[sup 17] cm[sup -3]. The existence of deep donor levels in this CdTe based ternary is not supposed to be the only reason for the reduction of the free carrier concentration. For high Mg support during molecular beam epitaxial (MBE) growth of wide gap (CdMg)Te layers, the ZnI[sub 2] incorporation is reduced, leading to low doping levels, too

  1. New developments in clinical applications of CdTe and CdZnTe detectors

    International Nuclear Information System (INIS)

    Scheiber, C.

    1996-01-01

    This review about the medical applications of CdTe and CdZnTe is an update on the 1992 paper (1992). This new paper is legitimized by the recent progress which has been made in this field. First of all, the usefulness of a new material, i.e. CdZnTe, has been demonstrated. While the two materials are still being improved, it seems as yet too early to debate which of CdTe:Cl or CdZnTe will be the best choice. Historical applications span over the past 18 years, involving devices like miniature probes for per-operative scintigraphy or the monitoring of physiological functions and, closer to us, appliances dedicated to bone densitometry, and have been expanding as such devices have become commercially available, for many years now. Newly available microelectronic circuitry allows 2D-arrays to be built for digital quantitative X-ray (chest, dental..) and for high-resolution gamma cameras. The clinical demand is very high, especially in the field of nuclear medicine. Although there already exist clinical demonstrators, the future of such CdTe applications depends on further reduction in material and device mounting costs. New perspectives concern XCT applications, but the data resulting from research work are kept for restricted use within industrial R and D laboratories. (orig.)

  2. Excitons in tunnel coupled CdTe and (Cd,Mn)Te quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Terletskii, Oleg; Ryabchenko, Sergiy; Tereshchenko, Oleksandr [Institute of Physics NASU, pr. Nauki 46, 03680 Kyiv (Ukraine); Sugakov, Volodymyr; Vertsimakha, Ganna [Institute for Nuclear Research NASU, pr. Nauki 47, 03680 Kyiv (Ukraine); Karczewski, Grzegorz [Institute of Physics PAS, Al. Lotnikow 32/46, PL-02-668 Warsaw (Poland)

    2017-05-15

    The photoluminescence (PL) from structures containing Cd{sub 0.95}Mn{sub 0.05}Te and CdTe quantum wells (QWs) separated by a narrow (1.94 nm) barrier was studied. The PL lines of comparable intensities from several possible exciton states were observed simultaneously at energy distances substantially exceeding kT. This means that the energy transfer in the studied systems is slower than the radiative recombination of the confined excitons. For the CdTe QW width of about 8.7-9 nm, indirect excitons with the electron and heavy hole chiefly localized in the CdTe and Cd{sub 1-x}Mn{sub x}Te QWs, respectively, were detected in the magnetic field. These indirect excitons have PL energy of about 10-20 meV above the PL line of the direct excitons in the CdTe QW. The observation of the PL from the indirect excitons which are not the lowest excitations in the structure is a distinctive feature of the system. Photoluminescence intensity dependence on the energy and the magnetic field. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Uma contribuição pedagógica acerca da criação e utilização dos objetos de aprendizagem na capacitação do controlador de tráfego aéreo

    OpenAIRE

    Elaine Pires de Abreu

    2014-01-01

    Este trabalho trata do uso de objetos de aprendizagem (OA) na formação e treinamento continuado de controladores de tráfego aéreo. A capacitação das pessoas que trabalham no controle de tráfego aéreo é um importante fator de segurança operacional. Partindo das teorias de aprendizagem de adultos, colaborativa, significativa e multimídia, a pesquisa toma como referência as metodologias LODAS e ISD-ADDIE para propor um método inovador de desenvolvimento e utilização de OA para uso na formação e ...

  4. Anomalous Phase Change in [(GeTe)2/(Sb2Te3)]20 Superlattice Observed by Coherent Phonon Spectroscopy

    Science.gov (United States)

    Makino, K.; Saito, Y.; Mitrofanov, K.; Tominaga, J.; Kolobov, A. V.; Nakano, T.; Fons, P.; Hase, M.

    The temperature-dependent ultrafast coherent phonon dynamics of topological (GeTe)2/(Sb2Te3) super lattice phase change memory material was investigated. By comparing with Ge-Sb-Te alloy, a clear contrast suggesting the unique phase change behavior was found.

  5. Composição florística do componente arbustivo-arbóreo em dois trechos de floresta estacional semidecidual na Mata do Paraíso, Viçosa, MG

    Directory of Open Access Journals (Sweden)

    Sheila Isabel do Carmo Pinto

    2013-09-01

    Full Text Available É grande a demanda por estudos ecológicos em florestas que possam embasar trabalhos de recuperação e conservação da biodiversidade. Entre esses estudos, primordialmente está o levantamento da flora. Nesse sentido, realizou-se o estudo das variações florísticas do componente arbustivo-arbóreo em dois trechos de Floresta Estacional Semidecidual, floresta inicial e floresta madura, situados na Reserva Florestal Mata do Paraíso, em Viçosa, Minas Gerais. As espécies arbóreo-arbustivas foram amostradas dentro de 20 parcelas de 10 x 30 m, 10 parcelas em cada trecho de floresta, sendo considerados apenas os indivíduos com diâmetro a 1,30 m do solo (DAP  4,8 cm. Na floresta inicial foram amostradas 55 espécies pertencentes a 47 gêneros e 27 famílias. A família com maior riqueza florística foi Fabaceae, com 10 espécies (18%, seguida de Euphorbiaceae (cinco espécies; 9%, Annonaceae, Lauraceae, Meliaceae e Salicaceae (três espécies; 6%. Na floresta madura foram amostradas 78 espécies distribuídas em 62 gêneros e 31 famílias. A família com maior riqueza florística foi Fabaceae, com 13 espécies (17%, seguida de Lauraceae e Myrtaceae (seis espécies; 8%, Euphorbiaceae, Sapindaceae e Salicaceae (cinco espécies; 6%, Annonaceae e Meliaceae (quatro espécies, 5%, Rubiaceae e Moraceae (três espécies; 4%. O grupo ecológico que mais se destacou nos dois trechos de floresta foi o das secundárias iniciais, seguido pelas secundárias tardias na floresta madura e pelas pioneiras na floresta inicial. A variabilidade na composição florística e na proporção de espécies em cada grupo ecológico foi resultante das variações na intensidade da ação antrópica nestas florestas e do tempo de regeneração florestal.

  6. Florística e estrutura do componente arbóreo e análise ambiental de um fragmento de Floresta Ombrófila Mista Alto-Montana no município de Painel, SC

    Directory of Open Access Journals (Sweden)

    Pedro Higuchi

    2013-03-01

    Full Text Available http://dx.doi.org/10.5902/198050988449A Floresta Ombrófila Mista Alto-Montana é uma formação pouco estudada que ocorre em altitudes acima de 1.000 m. Os objetivos deste estudo foram conhecer os padrões florísticos e estruturais do componente arbóreo de um fragmento desta floresta na região do Planalto Sul Catarinense e determinar as variáveis ambientais que influenciam esses padrões. O levantamento da composição florística e estrutural e a coleta das variáveis ambientais foram conduzidos em 50 parcelas de 200 m2. Nelas, todos os indivíduos arbóreos com CAP (circunferência medida a altura do peito ≥ 15,7 cm foram medidos (CAP e altura e identificados. Foram coletadas, em cada parcela, variáveis ambientais relacionadas às características químicas e físicas dos solos, topográficas e de cobertura do dossel. Foram calculados os parâmetros fitossociológicos e a estrutura diamétrica da comunidade e das populações com valor de importância (VI acima de 5 %. A similaridade florístico-estrutural entre as parcelas foi analisada pela NMDS (Nonmetric Multidimensional Scaling e os vetores das variáveis ambientais significativas (p < 0,05 foram plotados a posteriori. Foram identificadas 50 espécies arbóreas distribuídas em 33 gêneros e 20 famílias botânicas. As espécies com maior VI foram: Araucaria angustifolia (Bertol. Kuntze (17,32 %, Myrceugenia euosma (O.Berg D.Legrand (15,24 % e Acca sellowiana (O.Berg Burret (7,84 %. A estrutura diamétrica de toda a comunidade e das populações estudadas (exceto Dicksonia sellowiana Hook. teve distribuição próxima ao “J invertido”. A análise NMDS demonstrou maior porcentagem de argila nas parcelas com maior densidade de Araucaria angustifolia e menor porcentagem, nas parcelas com maior densidade de Dicksonia sellowiana, Inga lentiscifolia Benth. e Ocotea pulchella Mart. As parcelas de maior declividade tiveram maior densidade de Drimys brasiliensis Miers e aquelas de

  7. Density of liquid Hg(1-x)Cd(x)Te

    Science.gov (United States)

    Chandra, D.; Holland, L. R.

    1983-01-01

    Negative thermal expansion has been established in liquid Hg(1-x)Cd(x)Te for x less than 0.2 employing a pycnometric method. Pure HgTe increases in density from its melting point at 670 C to a maximum value at 750 C, where normal thermal expansion progressively resumes. The dependence of density on temperature for liquid Hg(1-x)Cd(x)Te arises almost exclusively from the HgTe portion of the melt, while CdTe acts as a diluent. The temperature corresponding to the maximum density changes slightly with composition, increasing by about 5 C for x = 0.1.

  8. Zn2(TeO3Br2

    Directory of Open Access Journals (Sweden)

    Mats Johnsson

    2008-05-01

    Full Text Available Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetrahedra, and [TeO3E] tetrahedra (E being the 5s2 lone pair of Te4+ joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3Br2 is isostructural with the synthetic compounds Zn2(TeO3Cl2, CuZn(TeO32, Co2(TeO3Br2 and the mineral sophiite, Zn2(SeO3Cl2.

  9. Properties of Hg1-xCdxTe epitaxial films grown on (211)CdTe and (211)CdZnTe

    International Nuclear Information System (INIS)

    Di Stefano, M.C.; Gilabert, U.; Heredia, E.; Trigubo, A.B.

    2004-01-01

    Hg 1-x Cd x Te (MCT) epitaxial films have been grown employing single crystalline substrates of CdTe and Cd 0.96 Zn 0.04 Te with (211)Cd and (211)Te crystalline orientations. The Isothermal Vapor Phase Epitaxy (ISOVPE) technique without Hg overpressure has been used for the epitaxial growth. Substrates and films were characterized by optical microscopy, chemical etching and X ray diffraction (Laue technique). The electrical properties were determined by Hall effect measurements. The characterization results allowed to evaluate the crystalline quality of MCT films. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. TeV gravity in four dimensions?

    International Nuclear Information System (INIS)

    Calmet, Xavier; Hsu, Stephen D.H.

    2008-01-01

    We describe a model in which the fundamental scale M * of the theory which unifies gravity and quantum mechanics is in the TeV range, but without requiring additional spacetime dimensions. The weakness of gravity at low energies is due to a large vacuum expectation of a dilaton like field. The model requires a small dimensionless parameter (the self-coupling of the dilaton) but no fine-tuning. We discuss in detail the dynamical assumptions about non-perturbative quantum gravity required within the model. We observe that M * could be quite small, less than a TeV, and that the model could lead to copious strong coupling effects at the LHC. However, semiclassical black holes will not be produced

  11. Optically detected SdH oscillations in CdTe/(CdMg)Te and CdTe/(CdMnMg)Te modulation doped quantum wells

    International Nuclear Information System (INIS)

    Shen, J.X.; Ossau, W.; Fischer, F.; Waag, A.; Landwehr, G.

    1995-01-01

    Oscillations of photoluminescence properties in external magnetic fields are investigated in CdTe modulation doped quantum wells. The oscillatory behaviour of the luminescence intensity, the line width and the g factor is due to many-body effects in the 2-dimensional electron gas. The oscillation of photoluminescence intensity can be easily used as optically detected Shubnikov de Haas effect to determine the electron concentration in quantum wells without contacts. (author)

  12. Optically detected SdH oscillations in CdTe/(CdMg)Te and CdTe/(CdMnMg)Te modulation doped quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Shen, J.X.; Ossau, W.; Fischer, F.; Waag, A.; Landwehr, G. [Physikalisches Institut der Uniwersitaet Wuerzburg, Wuerzburg (Germany)

    1995-12-31

    Oscillations of photoluminescence properties in external magnetic fields are investigated in CdTe modulation doped quantum wells. The oscillatory behaviour of the luminescence intensity, the line width and the g factor is due to many-body effects in the 2-dimensional electron gas. The oscillation of photoluminescence intensity can be easily used as optically detected Shubnikov de Haas effect to determine the electron concentration in quantum wells without contacts. (author). 5 refs, 3 figs, 1 tab.

  13. Multi-TeV muon colliders

    International Nuclear Information System (INIS)

    Neuffer, D.

    1986-01-01

    The possibility that muons may be used in a future generation of high-energy high-luminosity μ + μ - and μ - p colliders is presented. The problem of collecting and cooling high-intensity muon bunches is discussed and ionization cooling is described. High-energy collider scenarios are outlined; muon colliders may become superior to electron colliders in the multi-TeV energy range

  14. Refugios antiaéreos de la ciudad de Valencia: estudio, propuesta y desarrollo como paisajes culturales urbanos = Air-Raid Shelters of Valencia City: Study, Proposal and Development as Urban Cultural Landscapes

    Directory of Open Access Journals (Sweden)

    Fernando Collado Lozano

    2017-06-01

    Full Text Available Elpresente trabajo pretende mostrar como paisajes culturales urbanos los refugios antiaéreos de la ciudad de Valencia. El desarrollo y finalidad del estudio proyecta demostrar el vacío existente en cuanto a la puesta en valor del patrimonio de la Guerra Civil en Valencia, enfatizando las actuaciones sobre las construcciones defensivas de ámbito civil. Este escrito plantea un recorrido por el panorama actual de los paisajes culturales urbanos. Para ello, se expone la legislación vigente que atañe a esta situación, así como una propuesta de desarrollo patrimonial de los refugios urbanos de Valencia mediante la exhibición de otros refugios que sí han recibido tratamiento como museos y centros de difusión didáctica y cultural. This paper aims to show how urban cultural landscapes air-raid shelters in the city of Valencia. The development and purpose of the study projects demonstrate the gap in terms of enhancement of the heritage of the Civil War in Valencia, emphasizing defensive actions on civil construction area. This paper presents a tour of the current landscape of urban cultural landscapes. To do so, the legislation regards this situation as well as a proposal for development of urban heritage shelters Valencia by showing other shelters who have received treatment as museums and educational and cultural diffusion is exposed.

  15. The Hadean upper mantle conundrum: evidence for source depletion and enrichment from Sm-Nd, Re-Os, and Pb isotopic compositions in 3.71 Gy boninite-like metabasalts from the Isua Supracrustal Belt, Greenland

    Science.gov (United States)

    Frei, Robert; Polat, Ali; Meibom, Anders

    2004-04-01

    Here we present Sm-Nd, Re-Os, and Pb isotopic data of carefully screened, least altered samples of boninite-like metabasalts from the Isua Supracrustal Belt (ISB, W Greenland)that characterize their mantle source at the time of their formation. The principal observations of this study are that by 3.7-3.8 Ga melt source regions existed in the upper mantle with complicated enrichment/depletion histories. Sm-Nd isotopic data define a correlation line with a slope corresponding to an age of 3.69 ± 0.18 Gy and an initial εNd value of +2.0 ± 4.7. This Sm-Nd age is consistent with indirect (but more precise) U-Pb geochronological estimates for their formation between 3.69-3.71 Ga. Relying on the maximum formation age of 3.71 Gy defined by the external age constraints, we calculate an average εNd [T = 3.71 Ga] value of +2.2 ± 0.9 (n = 18, 1σ) for these samples, which is indicative of a strongly depleted mantle source. This is consistent with the high Os concentrations, falling in the range between 1.9-3.4 ppb, which is similar to the estimated Os concentration for the primitive upper mantle. Re-Os isotopic data (excluding three outliers) yield an isochron defining an age of 3.76 ± 0.09 Gy (with an initial γOs value of 3.9 ± 1.2), within error consistent with the Sm-Nd age and the indirect U-Pb age estimates. An average initial γOs [T = 3.71 Ga] value of + 4.4 ± 1.2 (n = 8; 2σ) is indicative of enrichment of their source region during, or prior to, its melting. Thus, this study provides the first observation of an early Archean upper mantle domain with a distinctly radiogenic Os isotopic signature. This requires a mixing component characterized by time-integrated suprachondritic Re/Os evolution and a Os concentration high enough to strongly affect the Os budget of the mantle source; modern sediments, recycled basaltic crust, or the outer core do not constitute suitable candidates. At this point, the nature of the mantle or crustal component responsible for the

  16. Consideraciones para el rediseño de la línea de ensamble de vehículos aéreos no tripulados desarrollados por la Fuerza Aérea Ecuatoriana

    Directory of Open Access Journals (Sweden)

    Ricardo Daniel Fiallos Castillo

    2016-01-01

    Full Text Available Este trabajo tiene como objetivo el re-diseño de la línea de ensamblaje de los vehículos aéreos no tripulados (por siglas en inglés, UAVs destinados a realizar diversas misiones a grandes alturas llevadas a cabo en el Centro de Investigación y Desarrollo de la Fuerza Aérea Ecuatoriana (CIDFAE. La metodología que se aplicó consta de tres fases: la primera comprende el análisis de la situación estratégica actual; la segunda estima la capacidad del proceso productivo con el uso de las normas de tiempo predeterminadas en base al sistema MTM-2; la tercera realiza el estudio de la distribución de las instalaciones mediante simulación. Como resultado final se opta por una distribución mixta que garantiza una producción en serie de UAVs. La construcción de piezas se realiza en células de fabricación; y el ensamble final por estaciones de trabajo; además se establecen estrategias para el fortalecimiento de la capacidad operativa de producción de la instalación que se proyecta a tres UAVs, producidos cada dos meses

  17. Correction of diagnostic x-ray spectra measured with CdTe and CdZnTe detectors

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, M [Osaka Univ., Suita (Japan). Medical School; Kanamori, H; Toragaito, T; Taniguchi, A

    1996-07-01

    We modified the formula of stripping procedure presented by E. Di. Castor et al. We added the Compton scattering and separated K{sub {alpha}} radiation of Cd and Te (23 and 27keV, respectively). Using the new stripping procedure diagnostic x-ray spectra (object 4mm-Al) of tube voltage 50kV to 100kV for CdTe and CdZnTe detectors are corrected with comparison of those spectra for the Ge detector. The corrected spectra for CdTe and CdZnTe detectors coincide with those for Ge detector at lower tube voltage than 70kV. But the corrected spectra at higher tube voltage than 70kV do not coincide with those for Ge detector. The reason is incomplete correction for full energy peak efficiencies of real CdTe and CdZnTe detectors. (J.P.N.)

  18. TeV gravity at neutrino telescopes

    International Nuclear Information System (INIS)

    Illana, J.I.; Masip, M.; Meloni, D.

    2005-01-01

    Cosmogenic neutrinos reach the Earth with energies around 10 9 GeV, and their interactions with matter will be measured in upcoming experiments (Auger, IceCube). Models with extra dimensions and the fundamental scale at the TeV could imply signals in these experiments. In particular, the production of microscopic black holes by cosmogenic neutrinos has been extensively studied in the literature. Here we make a complete analysis of gravity-mediated interactions at larger distances, where they can be calculated in the eikonal approximation. In these processes a neutrino of energy E ν interacts elastically with a parton inside a nucleon, loses a small fraction y of its energy, and starts a hadronic shower of energy yE ν ν . We analyze the ultraviolet dependence and the relevance of graviton emission in these processes, and show that they are negligible. We also study the energy distribution of cosmogenic events in AMANDA and IceCube and the possibility of multiple-bang events. For any neutrino flux, the observation of an enhanced rate of neutral current events above 100 TeV in neutrino telescopes could be explained by TeV-gravity interactions. The values of the fundamental scale of gravity that IceCube could reach are comparable to those to be explored at the LHC

  19. Surface preparation effects on efficient indium-tin-oxide-CdTe and CdS-CdTe heterojunction solar cells

    Science.gov (United States)

    Werthen, J. G.; Fahrenbruch, A. L.; Bube, R. H.; Zesch, J. C.

    1983-05-01

    The effects of CdTe surface preparation and subsequent junction formation have been investigated through characterization of ITO/CdTe and CdS/CdTe heterojunction solar cells formed by electron beam evaporation of indium-tin-oxide (ITO) and CdS onto single crystal p-type CdTe. Surfaces investigated include air-cleaved (110) surfaces, bromine-in-methanol etched (110) and (111) surfaces, and teh latter surfaces subjected to a hydrogen heat treatment. Both air-cleaved and hydrogen heat treated surfaces have a stoichiometric Cd to Te ratio. The ITO/CdTe junction formation process involves an air heat treatment, which ahs serious effects on the behavior of junctions formed on these surfaces. Etched surfaces which have a large excesss of Te, are less affected by the junction formation process and result in ITO/CdTe heterojunctions with solar efficiencies of 9% (Vsc =20 mA/cm2). Use of low-doped CdTe results in junctions characterized by considerably larger open-circuit votages (Voc =0.81 V) which are attributable to increasing diode factors caused by a shift from interfacial recombination to recombination in the depletion region. Resulting solar efficiencies reach 10.5% which is the highest value reported to date for a genuine CdTe heterojunction, CdS/CdTe heterojunctions show a strong dependence on CdTe surface condition, but less influence on the junction formation process. Solar efficiencies of 7.5% on an etched and heat treated surface are observed. All of these ITO/CdTe and CdS/CdTe heterojunctions have been stable for at least 10 months.

  20. New chalcogenide glasses in the CdTe-AgI-As{sub 2}Te{sub 3} system

    Energy Technology Data Exchange (ETDEWEB)

    Kassem, M. [Univ. Picardie Jules Verne, F-80000 Amiens (France); Le Coq, D., E-mail: david.lecoq@univ-littoral.fr [Univ. Lille Nord de France, F-59000 Lille (France); ULCO, LPCA, EA 4493, F-59140 Dunkerque (France); Boidin, R.; Bychkov, E. [Univ. Lille Nord de France, F-59000 Lille (France); ULCO, LPCA, EA 4493, F-59140 Dunkerque (France)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Determination of the glass-forming region in the pseudo-ternary CdTe-AgI-As{sub 2}Te{sub 3} system. Black-Right-Pointing-Pointer Characterization of macroscopic properties of the new CdTe-AgI-As{sub 2}Te{sub 3} glasses. Black-Right-Pointing-Pointer Characterization of the total conductivity of CdTe-AgI-As{sub 2}Te{sub 3} glasses. Black-Right-Pointing-Pointer Comparison between the selenide and telluride equivalent systems. -- Abstract: Chalcogenide glasses in the pseudo-ternary CdTe-AgI-As{sub 2}Te{sub 3} system were synthesized and the glass-forming range was determined. The maximum content of CdTe in this glass system was found to be equal to 15 mol.%. The macroscopic characterizations of samples have consisted in Differential Scanning Calorimetry, density, and X-ray diffraction measurements. The cadmium telluride addition does not generate any significant change in the glass transition temperature but the resistance of binary AgI-As{sub 2}Te{sub 3} glasses towards crystallisation is estimated to be decreasing on the base of {Delta}T = T{sub x} - T{sub g} parameter. The total electrical conductivity {sigma} was measured by complex impedance spectroscopy. First, the CdTe additions in the (AgI){sub 0.5}(As{sub 2}Te{sub 3}){sub 0.5} host glass, (CdTe){sub x}(AgI){sub 0.5-x/2}(As{sub 2}Te{sub 3}){sub 0.5-x/2} lead to a conductivity decrease at x {<=} 0.05. Then, the behaviour is reversed at 0.05 {<=} x {<=} 0.15. The obtained results are discussed by comparison with the equivalent selenide system.

  1. Optical spectroscopy and Fermi surface studies of BiTeCl and BiTeBr

    Science.gov (United States)

    Martin, Catalin; Suslov, A. V.; Buvaev, S.; Hebard, A. F.; Bugnon, Philippe; Berger, Helmuth; Magrez, Arnaud; Tanner, D. B.

    2014-03-01

    The observation of a large bulk Rashba effect in the non-centrosymmetric semiconductors BiTeX(X=Cl, Br, I) has stimulated the interest in these sys- tems, as promising candidates for studying spin related phenomena and for the realization of spin devices. Here we present a comparative study of the electronic properties of BiTeCl and BiTeBr, determined from temperature dependent infrared spectroscopy and Shubnikov-de Haas oscillations. In par- ticular, we compare the angle dependence of quantum oscillations between the two compounds and discuss possible differences between the topology of their Fermi surfaces. Supported by NSF Cooperative Agreement DMR-1157490 to the National High Magnetic Field Laboratory.

  2. Performance and Metastability of CdTe Solar Cells with a Te Back-Contact Buffer Layer

    Science.gov (United States)

    Moore, Andrew

    Thin-film CdTe photovoltaics are quickly maturing into a viable clean-energy solution through demonstration of competitive costs and performance stability with existing energy sources. Over the last half decade, CdTe solar technology has achieved major gains in performance; however, there are still aspects that can be improved to progress toward their theoretical maximum efficiency. Perhaps equally valuable as high photovoltaic efficiency and a low levelized cost of energy, is device reliability. Understanding the root causes for changes in performance is essential for accomplishing long-term stability. One area for potential performance enhancement is the back contact of the CdTe device. This research incorporated a thin-film Te-buffer layer into the contact structure, between the CdTe and contact metal. The device performance and characteristics of many different back contact configurations were rigorously studied. CdTe solar cells fabricated with the Te-buffer contact showed short-circuit current densities and open-circuit voltages that were on par with the traditional back-contacts used at CSU. However, the Te-buffer contact typically produced 2% larger fill-factors on average, leading to greater conversation efficiency. Furthermore, using the Te buffer allowed for incorporation of 50% less Cu, which is used for p-type doping but is also known to decrease lifetime and stability. This resulted in an additional 3% fill-factor gain with no change in other parameters compared to the standard-Cu treated device. In order to better understand the physical mechanisms of the Te-buffer contact, electrical and material properties of the Te layer were extracted and used to construct a simple energy band diagram. The Te layer was found to be highly p-type (>1018 cm-3) and possess a positive valence-band offset of 0.35-0.40 eV with CdTe. An existing simulation model incorporating the Te-layer properties was implemented and validated by comparing simulated results of CdTe

  3. Thermal annealing studies of GeTe-Sb2Te3 alloys with multiple interfaces

    Directory of Open Access Journals (Sweden)

    Valeria Bragaglia

    2017-08-01

    Full Text Available A high degree of vacancy ordering is obtained by annealing amorphous GeTe-Sb2Te3 (GST alloys deposited on a crystalline substrate, which acts as a template for the crystallization. Under annealing the material evolves from amorphous to disordered rocksalt, to ordered rocksalt with vacancies arranged into (111 oriented layers, and finally converts into the stable trigonal phase. The role of the interface in respect to the formation of an ordered crystalline phase is studied by comparing the transformation stages of crystalline GST with and without a capping layer. The capping layer offers another crystallization interface, which harms the overall crystalline quality.

  4. Orbital-dependent Rashba coupling in bulk BiTeCl and BiTeI

    KAUST Repository

    Zhu, Zhiyong; Cheng, Yingchun; Schwingenschlö gl, Udo

    2013-01-01

    By all-electron ab initio calculations, the layered polar semiconductor BiTeCl is shown to host giant bulk Rashba spin splitting, similar to the recently reported compound BiTeI. In both materials, the standard Rashba–Bychkov model is no longer applicable, because of huge band extrema shifts even in the absence of spin–orbit coupling and a strong momentum dependence of the Rashba coupling constant (αR). By assuming αR to be orbital dependent, a phenomenological extension of the Rashba–Bychkov model is proposed which explains the splitting behavior of states with small in-plane momentum.

  5. Improvements in 130Te double beta decay search with cryogenic TeO2 array detectors

    International Nuclear Information System (INIS)

    Alessandrello, A.; Brofferio, C.; Bucci, C.; Caspani, P.; Cremonesi, O.; Fiorini, E.; Giuliani, A.; Nucciotti, A.; Pavan, M.; Pessina, G.; Previtali, E.; Zanotti, L.

    1996-01-01

    Single crystal TeO 2 bolometers have been used since 5 years ago to search for neutrinoless DBD of 130 Te. During the last year, our group has been studying and preparing the first array of 4 crystals, 340 g each, opening this technique to new frontiers in rare events' physics. The results and perspectives of this second generation cryogenic detectors are here reported and discussed, with particular emphasis on the peculiarities which make them feasible for a consistent upgrading of our previous result in DBD search. (orig.)

  6. Orbital-dependent Rashba coupling in bulk BiTeCl and BiTeI

    KAUST Repository

    Zhu, Zhiyong

    2013-02-06

    By all-electron ab initio calculations, the layered polar semiconductor BiTeCl is shown to host giant bulk Rashba spin splitting, similar to the recently reported compound BiTeI. In both materials, the standard Rashba–Bychkov model is no longer applicable, because of huge band extrema shifts even in the absence of spin–orbit coupling and a strong momentum dependence of the Rashba coupling constant (αR). By assuming αR to be orbital dependent, a phenomenological extension of the Rashba–Bychkov model is proposed which explains the splitting behavior of states with small in-plane momentum.

  7. HgTe-CdTe phase diagrams calculation by RAS model

    International Nuclear Information System (INIS)

    Hady, A.A.A.

    1986-11-01

    The model of Regular Associated Solutions (RAS) for binary solution, which extended onto the ternary solution was used for Mercury-Cadnium-Tellurim phase diagrams calculations. The function of dissociation parameters is used here as a function of temperature and it is independent of composition. The ratio of mole fractions has a weak dependence on temperature and is not neglected. The calculated liquidus binary temperature and the experimental one are so fitted to give the best values of parameters used to calculate the HgTe-CdTe phase diagrams. (author)

  8. Terahertz emission from CdHgTe/HgTe quantum wells with an inverted band structure

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, Yu. B., E-mail: Yu.Vasilyev@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Mikhailov, N. N. [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation); Vasilyeva, G. Yu.; Ivánov, Yu. L.; Zakhar’in, A. O.; Andrianov, A. V. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Vorobiev, L. E.; Firsov, D. A. [Peter the Great Saint-Petersburg Polytechnic University (Russian Federation); Grigoriev, M. N. [Ustinov Baltic State Technical University “VOENMEKh” (Russian Federation); Antonov, A. V.; Ikonnikov, A. V.; Gavrilenko, V. I. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2016-07-15

    The terahertz electroluminescence from Cd{sub 0.7}Hg{sub 0.3}Te/HgTe quantum wells with an inverted band structure in lateral electric fields is experimentally detected and studied. The emission-spectrum maximum for wells 6.5 and 7 nm wide is near 6 meV which corresponds to interband optical transitions. The emission is explained by state depletion in the valence band and conduction band filling due to Zener tunneling, which is confirmed by power-law current–voltage characteristics.

  9. Precipitation of Ag{sub 2}Te in the thermoelectric material AgSbTe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Sugar, Joshua D. [Materials Physics Department, Sandia National Laboratories, Livermore, CA (United States)], E-mail: jdsugar@sandia.gov; Medlin, Douglas L. [Materials Physics Department, Sandia National Laboratories, Livermore, CA (United States)

    2009-06-10

    The microstructure of AgSbTe{sub 2}, prepared by solidification, is investigated using electron microscopy. During solidification and thermal treatment, the material separates into a two-phase mixture of a rocksalt phase, which is Ag{sub 22}Sb{sub 28}Te{sub 50}, and silver telluride, Ag{sub 2}Te. Ag{sub 2}Te formation results either from eutectic solidification (large lamellar structures), or by solid-state precipitation (fine-scale particles). The crystal structure of the AgSbTe{sub 2} phase determined by electron diffraction is consistent with a rocksalt structure that has a disordered cation sublattice. A preferred crystallographic orientation relationship at the interface between the matrix and the low-temperature monoclinic Ag{sub 2}Te phase is defined and discussed. This orientation relationship is observed for both second-phase morphologies. In both cases, the orientation relationship originates from a topotactic (cube-on-cube) alignment of the Te sublattices in the initially cubic Ag{sub 2}Te and the matrix at elevated temperature. This Te sublattice alignment is retained as the Ag{sub 2}Te undergoes a cubic-to-monoclinic transformation during cooling. This orientation relationship is observed for both second-phase morphologies.

  10. Effects of Te inclusions on charge-carrier transport properties in CdZnTe radiation detectors

    International Nuclear Information System (INIS)

    Gu, Yaxu; Rong, Caicai; Xu, Yadong; Shen, Hao; Zha, Gangqiang; Wang, Ning; Lv, Haoyan; Li, Xinyi; Wei, Dengke; Jie, Wanqi

    2015-01-01

    Highlights: • This work reveals the behaviors of Te inclusion in affecting charge-carrier transport properties in CdZnTe detectors for the first time and analysis the mechanism therein. • The results show that charge collection efficiencies in Te inclusion degraded regions experience fast ascent under low biases and slow descent at high applied biases, which deviates from the Hecht rule. • This phenomenon is attributed to the competitive influence of two mechanisms under different biases, namely charge carrier trapping due to uniformly distributed point defects and Te inclusion induced transient charge loss. • A modified Hecht equation is further proposed to explain the effects of high-density localized defects, say Te inclusions, on the charge collection efficiency. • We believe that this research has wide appeal to analyze the macroscopic defects and their influence on charge transport properties in semiconductor radiation detectors. - Abstract: The influence of tellurium (Te) inclusions on the charge collection efficiency in cadmium zinc telluride (CdZnTe or CZT) detectors has been investigated using ion beam induced charge (IBIC) technique. Combining the analysis of infrared transmittance image, most of the low charge collection areas in the IBIC images prove the existence of Te inclusions. To further clarify the role of Te inclusions on charge transport properties, bias dependent local IBIC scan was performed on Te inclusion related regions from 20 V to 500 V. The result shows that charge collection efficiencies in Te inclusion degraded regions experience fast ascent under low biases and slow descent at high applied biases, which deviates from Hecht rule. This behavior is attributed to the competitive influence of two mechanisms under different biases, namely charge carrier trapping due to uniformly distributed point defects and Te inclusion induced transient charge loss. A modified Hecht equation is further proposed to explain the effects of high

  11. Preliminary study of CdTe and CdTe:Cu thin films nanostructures deposited by using DC magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Marwoto, Putut; Made, D. P. Ngurah; Sugianto [Departement of Physics, Faculty of Mathematics and Natural Sciences, Universitas Negeri Semarang, Gunungpati, Semarang 50229 Jawa Tengah (Indonesia); Wibowo, Edy; Astuti, Santi Yuli; Aryani, Nila Prasetya [Materials Research Group, Laboratory of Thin Film, Department of Physics, Universitas Negeri Semarang, Gunungpati, Semarang 50229 Jawa Tengah (Indonesia); Othaman, Zulkafli [Departement of Physics, Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru (Malaysia)

    2013-09-03

    Growth and properties of CdTe and CdTe:Cu thin films nanostrucures deposited by using dc magnetron sputtering are reported. Scanning electron microscope (SEM) was used to observe the surface morphologies of the thin films. At growth conditions of 250 °C and 14 W, CdTe films did not yet evenly deposited. However, at growth temperature and plasma power of 325 °C and 43 W, both CdTe and CdTe:Cu(2%) have deposited on the substrates. In this condition, the morphology of the films indicate that the films have a grain-like nanostructures. Grain size diameter of about 200 nm begin to appear on top of the films. Energy Dispersive X-rays spectroscopy (EDX) was used to investigate chemical elements of the Cu doped CdTe film deposited. It was found that the film deposited consist of Cd, Te and Cu elements. XRD was used to investigate the full width at half maximum (FWHM) values of the thin films deposited. The results show that CdTe:Cu(2%) thin film has better crystallographic properties than CdTe thin film. The UV-Vis spectrometer was used to investigate the optical properties of thin films deposited. The transmittance spectra showed that transmittance of CdTe:Cu(2%) film is lower than CdTe film. It was found that the bandgap energy of CdTe and CdTe:Cu(2%) thin films of about 1.48 eV.

  12. HgCdTe photovoltaic detectors on Si substrates

    International Nuclear Information System (INIS)

    Zanio, K.R.; Bean, R.C.

    1988-01-01

    HgCdTe photovoltaic detectors have been fabricated on Si substrates through intermediate CdTe/GaAs layers. Encapsulation of the GaAs between the CdTe and Si prevents unintentional doping of the HgCdTe by Ga and As. Uniform epitaxial GaAs is grown on three inch diameter Si substrates. Detectors on such large area Si substrates will offer hybrid focal plane arrays whose dimensions are not limited by the difference between the coefficients of thermal expansion of the Si signal processor and the substrate for the HgCdTe detector array. The growth of HgCdTe detectors on the Si signal processors for monolithic focal plane arrays is also considered. 40 references

  13. Evaluation of Tp-Te Interval and Tp-Te/QT Ratio in Patients with Coronary Slow Flow Tp-Te/QT Ratio and Coronary Slow Flow.

    Science.gov (United States)

    Tenekecioglu, Erhan; Karaagac, Kemal; Yontar, Osman Can; Agca, Fahriye Vatansever; Ozluk, Ozlem Arican; Tutuncu, Ahmet; Arslan, Burhan; Yilmaz, Mustafa

    2015-06-01

    Coronary slow flow (CSF) phenomenon is described by angiographically normal coronary arteries with delayed opacification of the distal vasculature. Several studies have suggested that the interval from the peak to the end of the electrocardiographic T wave (Tp-Te) may correspond to the transmural dispersion of the repolarization and that increased Tp-Te interval and Tp-Te/QT ratio are associated with malignant ventricular arrhythmias. The aim of this study was to evaluate the ventricular repolarization by using Tp-Te interval and Tp-Te/QT ratio in patients with CSF. This study included 50 CSF patients (40 male, mean age 48.6±12.5 years) and 40 control individuals (23 male, mean age 47.8±12.5 years). Tp-Te interval and Tp-Te/QT ratio were measured from the 12-lead electrocardiogram. These parameters were compared in groups. Baseline characteristics of the study groups were comparable. In electrocardiographic parameters analysis, QT and corrected QT were similar in CSF patients compared to the controls (357±35.2 vs 362±38.0 milliseconds and 419±25.8 vs 430±44.2 milliseconds, all p value >0.05). Tp-Te interval, Tp-Te/QT and Tp-Te/QTc ratio were significantly higher in CSF patients (85±13.7 vs 74±9.9 milliseconds and 0.24±0.03 vs 0.20±0.02 and 0.20±0.03 vs 0.17±0.02 all p value ratio are prolonged in patients with CSF.

  14. Second harmonic generation in Te crystal using free electron laser

    CERN Document Server

    Yamauchi, T; Minehara, E J

    2002-01-01

    The second harmonic generation signal converted from the fundamental wavelength of 22 mu m of a free electron laser was observed for the first time using a birefringent Te crystal. The experimental conversion efficiency of Te crystal for second harmonic generation is 0.53%, which is equivalent to the theoretical value within a factor of 2. The Te crystal has been incorporated into an autocorrelator system to measure the micro-pulse width of infrared free electron laser successfully. (author)

  15. The optical properties of TeO2-Based Glasses

    International Nuclear Information System (INIS)

    Sahar, M.R.; Isahak, R.

    1994-01-01

    A series of binary glasses based on TeO2-PbCl2 has been prepared and their spectroscopy in the UV-Visible and IR regions has been investigated. It was found that the IR cut-off edge can go beyond 7μm and are largely influenced by the absorption due to Te-O-Te stretching vibrations around 638-644 cmsup -1 peaks

  16. The optical properties of TeO2-Based Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Sahar, M R; Isahak, R [University Technology of Malaysia, Skudai Johor (Malaysia)

    1994-03-01

    A series of binary glasses based on TeO2-PbCl2 has been prepared and their spectroscopy in the UV-Visible and IR regions has been investigated. It was found that the IR cut-off edge can go beyond 7{mu}m and are largely influenced by the absorption due to Te-O-Te stretching vibrations around 638-644 cmsup -1 peaks.

  17. Process for manufacture of Te microwire in glass insulation

    International Nuclear Information System (INIS)

    Bodiul, Pavel; Nicolaeva, Alibina; Konopko, Leonid; Bondarciuc, Nicolae

    2010-01-01

    The invention relates to the manufacturing of microwires in glass insulation and can be used in electronics and in the manufacturing of thermoelectrodes for thermoelectric sensors. The process for manufacture of Te microwire in glass insulation consists in softening the Te sample and its pulling in glass insulation. Near the microwire pulling zone through the furnace is maintained a temperature of 430-440 degrees Celsius, which causes the solidification firstly of Te microwire, and then of glass insulation. The result of the invention is to obtain Te microwires in glass insulation of high quality with a diameter of 50-100 μm and a length of 3-15 cm.

  18. HgSe(Te)-HgHal2 systems

    International Nuclear Information System (INIS)

    Pan'ko, V.V.; Khudolij, V.A.; Voroshilov, Yu.V.

    1989-01-01

    Using the methods of differential thermal and X-ray phase analyses the character of chemical interaction in the systems HgTe(Se)-HgHal 2 , where Hal is Cl, Br, I, is investigated. Formation of compounds Hg 3 Se 2 Hal 2 , Hg 3 Te 2 Hal 2 , Hg 3 TeCl 4 and Hg 3 TeBr 4 in these systems is established. The phase diagrams of the studied systems are presented. The parameters of elementary cells of the compounds with the unknown structure, as well as their unknown physicochemical properties, are determined

  19. Characterization of CdZnTe ambient temperature detectors

    International Nuclear Information System (INIS)

    Lavietes, A.

    1994-09-01

    A great deal of interest has been generated in the use of cadmium telluride (CdTe) and cadmium zinc telluride (CdZnTe) detectors for ambient temperature detection of radionuclides. The addition of zinc to CdTe provides several benefits that enhance the materials operational characteristics at ambient temperature. Recent movement in the industry is to produce larger volume detectors using CdZnTe without much known about the effects of larger geometry on performance. The purpose of this study is to get an idea of the relationship of detector performance to both area and thickness variations

  20. Homogeneous CdTe quantum dots-carbon nanotubes heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Kayo Oliveira [Grupo de Pesquisa em Química de Materiais – (GPQM), Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP 36301-160, São João del-Rei, MG (Brazil); Bettini, Jefferson [Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, CEP 13083-970, Campinas, SP (Brazil); Ferrari, Jefferson Luis [Grupo de Pesquisa em Química de Materiais – (GPQM), Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP 36301-160, São João del-Rei, MG (Brazil); Schiavon, Marco Antonio, E-mail: schiavon@ufsj.edu.br [Grupo de Pesquisa em Química de Materiais – (GPQM), Departamento de Ciências Naturais, Universidade Federal de São João del-Rei, Campus Dom Bosco, Praça Dom Helvécio, 74, CEP 36301-160, São João del-Rei, MG (Brazil)

    2015-01-15

    The development of homogeneous CdTe quantum dots-carbon nanotubes heterostructures based on electrostatic interactions has been investigated. We report a simple and reproducible non-covalent functionalization route that can be accomplished at room temperature, to prepare colloidal composites consisting of CdTe nanocrystals deposited onto multi-walled carbon nanotubes (MWCNTs) functionalized with a thin layer of polyelectrolytes by layer-by-layer technique. Specifically, physical adsorption of polyelectrolytes such as poly (4-styrene sulfonate) and poly (diallyldimethylammonium chloride) was used to deagglomerate and disperse MWCNTs, onto which we deposited CdTe quantum dots coated with mercaptopropionic acid (MPA), as surface ligand, via electrostatic interactions. Confirmation of the CdTe quantum dots/carbon nanotubes heterostructures was done by transmission and scanning electron microscopies (TEM and SEM), dynamic-light scattering (DLS) together with absorption, emission, Raman and infrared spectroscopies (UV–vis, PL, Raman and FT-IR). Almost complete quenching of the PL band of the CdTe quantum dots was observed after adsorption on the MWCNTs, presumably through efficient energy transfer process from photoexcited CdTe to MWCNTs. - Highlights: • Highly homogeneous CdTe-carbon nanotubes heterostructures were prepared. • Simple and reproducible non-covalent functionalization route. • CdTe nanocrystals homogeneously deposited onto multi-walled carbon nanotubes. • Efficient energy transfer process from photoexcited CdTe to MWCNTs.

  1. The system Sb2Te3-InS

    International Nuclear Information System (INIS)

    Safarov, M.G.; Gamidov, R.S.; Poladov, P.M.

    1991-01-01

    The system Sb 2 Te 3 -InS was investigated by the methods of physicochemical analysis. Its state diagram was constructed. It represents the stable diagonal of the mutual ternary system InTe-Sb 2 Te 3 -Sb 2 S 3 -InS. It was established that limited regions of α- and β-solid solutions on the basis of Sb 2 Te 3 and InS, achieving 15.5 and 8 mol.% respectively, formed in the system. Lattice periods of α- and β-solid solutions, their lattice volumes, number of atoms in them and densities were calculated

  2. ZnSe/ZnSeTe Superlattice Nanotips

    Directory of Open Access Journals (Sweden)

    Young SJ

    2010-01-01

    Full Text Available Abstract The authors report the growth of ZnSe/ZnSeTe superlattice nanotips on oxidized Si(100 substrate. It was found the nanotips exhibit mixture of cubic zinc-blende and hexagonal wurtzite structures. It was also found that photoluminescence intensities observed from the ZnSe/ZnSeTe superlattice nanotips were much larger than that observed from the homogeneous ZnSeTe nanotips. Furthermore, it was found that activation energies for the ZnSe/ZnSeTe superlattice nanotips with well widths of 16, 20, and 24 nm were 76, 46, and 19 meV, respectively.

  3. CdTe ambulatory ventricular function monitor

    International Nuclear Information System (INIS)

    Lazewatsky, J.L.; Alpert, N.M.; Moore, R.H.; Boucher, C.A.; Strauss, H.W.

    1979-01-01

    A prototype device consisting of two arrays of CdTe detectors, ECG amplifiers and gate, microprocessor, and tape recorder was devised to record simultaneous ECG and radionuclide blood pool data from the left ventricle for extended periods during normal activity. The device is intended to record information concerning both normal and abnormal physiology of the heart and to permit the evaluation of new pharmaceuticals under everyday conditions. Preliminary results indicate that the device is capable of recording and reading out data from both phantoms and patients

  4. Pixelated CdZnTe drift detectors

    DEFF Research Database (Denmark)

    Kuvvetli, Irfan; Budtz-Jørgensen, Carl

    2005-01-01

    A technique, the so-called Drift Strip Method (DSM), for improving the CdZnTe detector energy response to hard X-rays and gamma-rays was applied as a pixel geometry. First tests have confirmed that this detector type provides excellent energy resolution and imaging performance. We specifically...... report on the performance of 3 mm thick prototype CZT drift pixel detectors fabricated using material from eV-products. We discuss issues associated with detector module performance. Characterization results obtained from several prototype drift pixel detectors are presented. Results of position...

  5. TeV gravity at neutrino telescopes

    CERN Document Server

    Illana, J I; Meloni, D

    2005-01-01

    Cosmogenic neutrinos reach the Earth with energies around 10^9 GeV, and their interactions with matter will be measured in upcoming experiments (Auger, IceCube). Models with extra dimensions and the fundamental scale at the TeV could imply signals in these experiments. In particular, the production of microscopic black holes by cosmogenic neutrinos has been extensively studied in the literature. Here we make a complete analysis of gravity-mediated interactions at larger distances, where they can be calculated in the eikonal approximation. In these processes a neutrino of energy E_\

  6. BOREAS TE-11 Leaf Gas Exchange Measurements

    Science.gov (United States)

    Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Saugier, Bernard; Pontailler, J. Y.

    2000-01-01

    The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-11 (Terrestrial Ecology) team collected several data sets in support of its efforts to characterize and interpret information on the sap flow, gas exchange, and lichen photosynthesis of boreal vegetation and meteorological data of the area studied. This data set contains measurements of assimilation and transpiration conducted at the Old Jack Pine (OJP) site during the growing seasons of 1993 and 1994. The data are stored in ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  7. Standard model beyond the TeV

    International Nuclear Information System (INIS)

    Aurenche, P.

    1987-01-01

    The phenomenology of the standard model in the hadronic reactions in the 10 TeV range is described. The predictions of the model concerning the hadronic cross sections being based on the parton model, we first discuss the behaviour of the structure functions at the low values of X (x > 10 -4 ) which are attained at these energies and we show that the development of the leading logarithms equations allow us to calculate them. The production of W, Z, and gauge bosons and gauge boson pairs are reviewed. The Higgs boson production is discussed in detail according to his mass value [fr

  8. BOREAS TE-5 Soil Respiration Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Ehleriinger, Jim; Brooks, J. Renee; Flanagan, Larry

    2000-01-01

    The BOREAS TE-5 team collected measurements in the NSA and SSA on gas exchange, gas composition, and tree growth. Soil respiration data were collected from 26-May-94 to 07-Sep-94 in the BOREAS NSA and SSA to compare the soil respiration rates in different forest sites using a LI-COR 6200 soil respiration chamber (model 6299). The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distrobuted Activity Archive Center (DAAC).

  9. Determination of equilibrium phase composition in the Hg-HgTe-CdTe system by ''dew point'' method

    International Nuclear Information System (INIS)

    Vanyukov, A.V.; Krotov, I.I.; Ermakov, A.I.

    1978-01-01

    Using the ''dew point'' method a study has been made of the equilibrium composition of the solid and liquid phases in the Hg-HgTe-CdTe system at 404, 435 and 454 deg C. It has been pointed out that crystallization of cadmium-rich solid solutions of Cdsub(x)Hgsub(1-x) Te takes place from a liquid phase with a much higher concentration of Hg. The activity of Hg in the liquid phase increases along the liquidus isotherm in the direction from section Hg-HgTe to section HgCdTe in accordance with the increase of its concentration. An increase in activity of Hg in the solid phase of Cdsub(x)Hgsub(1-x)Te has been noted with the reduction of its concentration

  10. Developing an Effective Education Reform Model for Indigenous and Other Minoritized Students

    Science.gov (United States)

    Bishop, Alan Russell; Berryman, Mere Anne; Wearmouth, Janice Barbara; Peter, Mira

    2012-01-01

    Educational disparities between indigenous Maori students and those of the majority continue to be a major issue in New Zealand. Te Kotahitanga, an iterative research and development programme, which commenced in 2001, supports teachers to implement a relationship-based pedagogy in their classrooms in order to improve Maori students' achievement…

  11. Detección de obstáculos y espacios transitables en entornos urbanos para sistemas de ayuda a la conducción basados en algoritmos de visión estéreo implementados en GPU

    Directory of Open Access Journals (Sweden)

    B. Musleh

    2012-10-01

    Full Text Available Resumen: Tanto los sistemas avanzados de ayuda a la conducción (ADAS aplicados a la mejora de la seguridad vial, como los sistemas de navegación autónoma de vehículos, demandan sensores y algoritmos cada vez más complejos, capaces de obtener e interpretar información del entorno vial. En concreto, las mayores dificultades surgen a la hora de analizar la información proveniente de los entornos urbanos, debido a la diversidad de elementos con distintas características que existen en áreas urbanas. Estos sistemas requieren, cada vez más, que la interpretación de la información se realice en tiempo real para mejorar la toma de decisiones. Por otra parte, la visión estéreo es ampliamente utilizada en sistemas de modelado, dada la gran cantidad de información que proporciona, pero al mismo tiempo, los algoritmos basados en esta técnica requieren de un elevado tiempo de cómputo que dificulta su implementación en aplicaciones de tiempo real. En este trabajo se presenta un algoritmo basado en visión estéreo para la detección tanto de obstáculos como de espacios transitables en entornos urbanos y que ha sido implementado principalmente en GPU (Unidad de Procesamiento Gráfico para reducir el tiempo de cómputo y conseguir un funcionamiento en tiempo real. Abstract: Both advanced driver assistance systems (ADAS applied to the improvement of road safety, and autonomous navigation vehicle systems require more and more complex sensors and algorithms capable of obtaining and interpreting the information of the road environment. The greatest difficulties arise in analysing the information of the urban environments, because of the large number of elements which have different characteristics in urban areas. These systems require to interpret the information in real time to improve the decision-making. On the other hand, the stereo vision is usable in modeling systems because of the great amount of information that it provides, but at the

  12. Zircon U-Pb and molybdenite Re-Os geochronology and Sr-Nd-Pb-Hf isotopic constraints on the genesis of the Xuejiping porphyry copper deposit in Zhongdian, Northwest Yunnan, China

    Science.gov (United States)

    Leng, Cheng-Biao; Zhang, Xing-Chun; Hu, Rui-Zhong; Wang, Shou-Xu; Zhong, Hong; Wang, Wai-Quan; Bi, Xian-Wu

    2012-10-01

    The Xuejiping porphyry copper deposit is located in northwestern Yunnan Province, China. Tectonically, it lies in the southern part of the Triassic Yidun island arc. The copper mineralization is mainly hosted in quartz-dioritic and quartz-monzonitic porphyries which intruded into clastic-volcanic rocks of the Late Triassic Tumugou Formation. There are several alteration zones including potassic, strong silicific and phyllic, argillic, and propylitic alteration zones from inner to outer of the mineralized porphyry bodies. The ages of ore-bearing quartz-monzonitic porphyry and its host andesite are obtained by using the zircon SIMS U-Pb dating method, with results of 218.3 ± 1.6 Ma (MSWD = 0.31, N = 15) and 218.5 ± 1.6 Ma (MSWD = 0.91, N = 16), respectively. Meanwhile, the molybdenite Re-Os dating yields a Re-Os isochronal age of 221.4 ± 2.3 Ma (MSWD = 0.54, N = 5) and a weighted mean age of 219.9 ± 0.7 Ma (MSWD = 0.88). They are quite in accordance with the zircon U-Pb ages within errors. Furthermore, all of them are contemporary with the timing of the Garzê-Litang oceanic crust subduction in the Yidun arc. Therefore, the Xuejiping deposit could be formed in a continental margin setting. There are negative ɛNd(t) values ranging from -3.8 to -2.1 and relatively high initial 87Sr/86Sr ratios from 0.7051 to 0.7059 for the Xuejiping porphyries and host andesites. The (206Pb/204Pb)t, (207Pb/204Pb)t and (208Pb/204Pb)t values of the Xuejiping porphyries and host andesites vary from 17.899 to 18.654, from 15.529 to 15.626, and from 37.864 to 38.52, respectively, indicative of high radiogenic Pb isotopic features. In situ Hf isotopic analyses on zircons by using LA-MC-ICP-MS exhibit that there are quite uniform and slightly positive ɛHf(t) values ranging from -0.2 to +3.2 (mostly between 0 and +2), corresponding to relatively young single-stage Hf model ages from 735 Ma to 871 Ma. These isotopic features suggest that the primary magmas of the Xuejiping porphyries and

  13. U-Pb, Re-Os, and Ar/Ar geochronology of rare earth element (REE)-rich breccia pipes and associated host rocks from the Mesoproterozoic Pea Ridge Fe-REE-Au deposit, St. Francois Mountains, Missouri

    Science.gov (United States)

    Aleinikoff, John N.; Selby, David; Slack, John F.; Day, Warren C.; Pillers, Renee M.; Cosca, Michael A.; Seeger, Cheryl; Fanning, C. Mark; Samson, Iain

    2016-01-01

    Rare earth element (REE)-rich breccia pipes (600,000 t @ 12% rare earth oxides) are preserved along the margins of the 136-million metric ton (Mt) Pea Ridge magnetite-apatite deposit, within Mesoproterozoic (~1.47 Ga) volcanic-plutonic rocks of the St. Francois Mountains terrane in southeastern Missouri, United States. The breccia pipes cut the rhyolite-hosted magnetite deposit and contain clasts of nearly all local bedrock and mineralized lithologies.Grains of monazite and xenotime were extracted from breccia pipe samples for SHRIMP U-Pb geochronology; both minerals were also dated in one polished thin section. Monazite forms two morphologies: (1) matrix granular grains composed of numerous small (minerals includes Re-Os on fine-grained molybdenite and 40Ar/39Ar on muscovite, biotite, and K-feldspar.Ages (±2σ errors) obtained by SHRIMP U-Pb analysis are as follows: (1) zircon from the two host rhyolite samples have ages of 1473.6 ± 8.0 and 1472.7 ± 5.6 Ma; most zircon in late felsic dikes is interpreted as xenocrystic (age range ca. 1522–1455 Ma); a population of rare spongy zircon is likely of igneous origin and yields an age of 1441 ± 9 Ma; (2) pale-yellow granular monazite—1464.9 ± 3.3 Ma (no dated xenotime); (3) reddish matrix granular monazite—1462.0 ± 3.5 Ma and associated xenotime—1453 ± 11 Ma; (4) coarse glassy-yellow monazite—1464.8 ± 2.1, 1461.7 ± 3.7 Ma, with rims at 1447.2 ± 4.7 Ma; and (5) matrix monazite (in situ)—1464.1 ± 3.6 and 1454.6 ± 9.6 Ma, and matrix xenotime (in situ)—1468.0 ± 8.0 Ma. Two slightly older ages of cores are about 1478 Ma. The young age of rims on the coarse glassy monazite coincides with an Re-Os age of 1440.6 ± 9.2 Ma determined in this study for molybdenite intergrown with quartz and allanite, and with the age of monazite inclusions in apatite from the magnetite ore (Neymark et al., 2016). A 40Ar/39Ar age of 1473 ± 1 Ma was obtained for muscovite from a breccia pipe sample.Geochronology and

  14. Clonagem do camu-camu arbustivo em porta-enxertos de camu-camu arbustivo e arbóreo Cloning of shrubby camu-camu on shrubby and arboreal camu-camu rootstocks

    Directory of Open Access Journals (Sweden)

    Mario Moreira Filho

    2009-12-01

    Full Text Available O camu-camu (Myrciaria dubia (H.B.K. McVaugh, espécie frutífera nativa da Amazônia, de porte arbustivo, é propagado, normalmente, por sementes, ocasionando grande variação na entrada em frutificação e no ciclo de produção, bem como no teor de ácido ascórbico (vitamina C dos frutos. outra espécie de camu-camu, M. floribunda (West ex Willd. o. Berg, de porte arbóreo, ocorre em menor densidade na região amazônica. O objetivo deste trabalho foi avaliar a eficiência de diferentes métodos de enxertia e a compatibilidade interespecífica entre camu-camu arbustivo e camu-camu arbóreo na fase de formação de mudas de M. dubia. o ensaio foi desenvolvido no período de março a agosto de 2008, no Instituto Nacional de Pesquisas da Amazônia, em Manaus-AM, com delineamento experimental de blocos ao acaso, em esquema fatorial 4 (métodos de enxertia x 2 (espécies de porta-enxerto, com quatro repetições. M. dubia, como porta-enxerto, apresentou melhor percentual de pegamento de enxertos (78,4%, comparada a M. floribunda (49,3%. os melhores resultados na clonagem de M. dubia foram obtidos pelos métodos de garfagem, em que a parte aérea do porta-enxerto foi removida após 30 dias da enxertia: fenda lateral (89,3% e lateral com lingueta (79,3%. o menor resultado foi obtido nos métodos de garfagem, em que a parte aérea do porta-enxerto foi removida na ocasião da enxertia: topo em fenda cheia (51,6% e inglês complicado (31,5%.The camu-camu (Myrciaria dubia (H.B.K. McVaugh is a shrubby indigenous fruit species found in the floodplains of Amazonia region. There is considerable local and international commercial interest in this fruit, because of its high Vitamin C content. The species is commonly propagated by seeds, showing considerable variation in age of bearing, production cycle, fruit yields and Vitamin C contents. Another species, Myrciaria floribunda (West ex Willd. o. Berg, occurs less frequently in the region. The present study

  15. Studies for Muon Colliders at Center-of-Mass Energies of 10 TeV and 100 TeV

    International Nuclear Information System (INIS)

    King, Bruce J.

    1999-01-01

    Parameter lists are presented for speculative muon colliders at center-of-mass energies of 10 TeV and 100 TeV. The technological advances required to achieve the given parameters are itemized and discussed, and a discussion is given of the design goals and constraints. An important constraint for multi-TeV muon colliders is the need to minimize neutrino radiation from the collider ring

  16. PharmTeX: a LaTeX-Based Open-Source Platform for Automated Reporting Workflow.

    Science.gov (United States)

    Rasmussen, Christian Hove; Smith, Mike K; Ito, Kaori; Sundararajan, Vijayakumar; Magnusson, Mats O; Niclas Jonsson, E; Fostvedt, Luke; Burger, Paula; McFadyen, Lynn; Tensfeldt, Thomas G; Nicholas, Timothy

    2018-03-16

    Every year, the pharmaceutical industry generates a large number of scientific reports related to drug research, development, and regulatory submissions. Many of these reports are created using text processing tools such as Microsoft Word. Given the large number of figures, tables, references, and other elements, this is often a tedious task involving hours of copying and pasting and substantial efforts in quality control (QC). In the present article, we present the LaTeX-based open-source reporting platform, PharmTeX, a community-based effort to make reporting simple, reproducible, and user-friendly. The PharmTeX creators put a substantial effort into simplifying the sometimes complex elements of LaTeX into user-friendly functions that rely on advanced LaTeX and Perl code running in the background. Using this setup makes LaTeX much more accessible for users with no prior LaTeX experience. A software collection was compiled for users not wanting to manually install the required software components. The PharmTeX templates allow for inclusion of tables directly from mathematical software output as well and figures from several formats. Code listings can be included directly from source. No previous experience and only a few hours of training are required to start writing reports using PharmTeX. PharmTeX significantly reduces the time required for creating a scientific report fully compliant with regulatory and industry expectations. QC is made much simpler, since there is a direct link between analysis output and report input. PharmTeX makes available to report authors the strengths of LaTeX document processing without the need for extensive training. Graphical Abstract ᅟ.

  17. Utilização de um veículo aéreo não-tripulado em atividades de imageamento georeferenciado On the use of unmanned aerial vehicle for acquisition of georrefecend image data

    Directory of Open Access Journals (Sweden)

    Fabrício Ardais Medeiros

    2008-11-01

    Full Text Available Este trabalho teve por objetivo desenvolver subsídios para propor um procedimento alternativo para aquisição de dados, telemetria, monitoramento e georeferenciamento das atividades agrícolas, por meio da acoplagem de equipamentos eletrônicos a um Veículo Aéreo Não-Tripulado (VANT. Para tal, foi desenvolvido um VANT na Universidade Federal de Santa Maria, no qual foram acoplados equipamentos para a coleta de imagens e a aquisição de pontos de referência. O equipamento desenvolvido mostrou imenso potencial para ser utilizado como ferramenta auxiliar na localização de áreas com falhas de germinação, na infestação de invasoras e no mapeamento de área. O maior entrave a um melhor emprego deste equipamento refere-se à baixa qualidade das imagens geradas, mostrando a necessidade de reavaliações do aparato utilizado.The aim of this study consisted in developing and testing an alternative procedure for data acquisition, telemetry, monitoring and geo-referencing in agricultural fields. The proposed approach was implemented by placing dedicated electronic gear onboard Unmanned Aerial Vehicles (UAV. For this purpose an UAV was assembled at the Federal University in Santa Maria, Brazil and equipped with the required hardware for image and control points acquisition. Tests have shown that the proposed approach can be regarded as a valuable tool to detect areas affected by faulty germination, weed infestation and mapping in general. The tests have also shown that poor quality of the acquired image data was the main drawback in the equipment onboard the UAV, pointing to the need to reevaluate the system with regard to this particular aspect.

  18. Crystallization and memory programming characteristics of Ge-doped SbTe materials of varying Sb : Te ratio

    International Nuclear Information System (INIS)

    Jeong, Jeung-hyun; Lee, Hyun Seok; Lee, Suyoun; Lee, Taek Sung; Kim, Won Mok; Wu Zhe; Cheong, Byung-ki; Kim, Seul Cham; Oh, Kyu Hwan

    2009-01-01

    A phase change memory (PCM) utilizes resistivity changes accompanying fast transitions from an amorphous to a crystalline phase (SET) and vice versa (RESET). An investigation was made on the SET characteristics of PCM cells with Ge-doped SbTe (Ge-ST) materials of two different Sb : Te ratios (4.53 and 2.08). For the material of higher Sb : Te (4.53), a SET operation was completed within several tens of nanoseconds via nucleation-free crystallization whereas the material of lower Sb : Te (2.08) rendered a slower SET operation requiring several hundred nanoseconds for a nucleation-mediated crystallization. From measurements of nucleation and growth kinetics via laser-induced crystallization, the observed SET characteristics of the former case were found to derive from a growth time about 10 3 times shorter than the nucleation time and those of the latter from a much shorter nucleation time as well as a longer growth time than in the former case. The measured nucleation kinetics of the lower Sb : Te (2.08) material is unexpected from the existing data, which has led us to advance an interesting finding that there occurs a trend-reversing change in the nucleation kinetics of the Ge-ST materials around the eutectic composition (Sb : Te ∼2.6); nucleation is accelerated with the increase in the Sb : Te ratio above Sb : Te of 2.6, but with a decrease in the Sb : Te ratio below it.

  19. Noise in CdZnTe detectors

    International Nuclear Information System (INIS)

    Luke, P. N.; Amman, M.; Lee, J. S.; Manfredi, P. F.

    2000-01-01

    Noise in CdZnTe devices with different electrode configurations was investigated. Measurements on devices with guard-ring electrode structures showed that surface leakage current does not produce any significant noise. The parallel white noise component of the devices appeared to be generated by the bulk current alone, even though the surface current was substantially higher. This implies that reducing the surface leakage current of a CdZnTe detector may not necessarily result in a significant improvement in noise performance. The noise generated by the bulk current is also observed to be below full shot noise. This partial suppression of shot noise may be the result of Coulomb interaction between carriers or carrier trapping. Devices with coplanar strip electrodes were observed to produce a 1/f noise term at the preamplifier output. Higher levels of this 1/f noise were observed with decreasing gap widths between electrodes. The level of this 1/f noise appeared to be independent of bias voltage and leakage current but was substantially reduced after certain surface treatments

  20. Probing the TeV energy scale

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Despite its spectacular success, the Standard Model (SM) is widely believed to be incomplete. In fact there are good reasons to expect that new degrees of freedom, not present within the SM framework, will show up in particle collisions at TeV energies. Novel phenomena are, therefore, anticipated when this energy regime is explored at proton supercolliders such as the SSC or the LHC, and at the next generation of linear electron-positron colliders. Almost two hundred physicists, with roughly equal representation from North America, Europe and Asia, got together to discuss the physics possibilities of such colliders at the Second International Workshop on Physics and Experiments at Linear Electron-Positron Colliders, held during the last week of April in Waikoloa on the Big Island of Hawaii. It was the second in a series of international workshops which began in Saariselkä, Lapland, Finland in September 1991. The main theme of the workshop was the physics reach of, and the feasibility of experiments at, linear electron-positron colliders in the 300 GeV - 2 TeV collision energy region. Also discussed were the prospects for physics at electron-photon, photon-photon and electron-electron colliders

  1. Raman spectroscopy of glasses in the As–Te system

    International Nuclear Information System (INIS)

    Tverjanovich, A.; Rodionov, K.; Bychkov, E.

    2012-01-01

    For the first time, the Raman spectra of As x Te 1−x glasses, 0.2≤x≤0.6, have been measured over the entire glass-forming range. The spectra exhibit three broad spectral features attributed to vibrations of structural units having Te–Te, As–Te and As–As bonds. The observed chemical disorder in the glasses is discussed on the basis of partial bond fractions derived from the integrated intensity of the Raman modes. The underlying structural model suggests a dissociation of AsTe- or As 2 Te 3 -related units in the glass melt. The spectra of glasses quenched from different temperatures, as well as those of the annealed vitreous alloys, are consistent with predictions of the model. - Graphical abstract: Raman spectra of the As x Te 1−x glasses (0.2≤x≤0.4 and 0.4≤x≤0.6). Fractional concentrations of Te–Te, As–Te and As–As bonds in the As x Te 1−x glasses calculated using experimental Raman data. The solid lines represent predictions of the dissociation model assuming that the main chemically ordered structural units are related to AsTe. Highlights: ► For the first time, the Raman spectra of As x Te 1−x glasses, 0.2≤x≤0.6, were measured. ► The partial bond fractions were derived from the integrated intensity of the Raman modes. ► An empirical quantitative approach to the Raman data was proposed for the reaction modeling.

  2. Breast MRI at very short TE (minTE). Image analysis of minTE sequences on non-fat-saturated, subtracted T1-weighted images

    International Nuclear Information System (INIS)

    Wenkel, Evelyn; Janka, Rolf; Kaemmerer, Nadine; Uder, Michael; Hammon, Matthias; Brand, Michael; Hartmann, Arndt

    2017-01-01

    The aim was to evaluate a minimum echo time (minTE) protocol for breast magnetic resonance imaging (MRI) in patients with breast lesions compared to a standard TE (nTE) time protocol. Breasts of 144 women were examined with a 1.5 Tesla MRI scanner. Additionally to the standard gradient-echo sequence with nTE (4.8 ms), a variant with minimum TE (1.2 ms) was used in an interleaved fashion which leads to a better temporal resolution and should reduce the scan time by approximately 50%. Lesion sizes were measured and the signal-to-noise ratio (SNR) as well as the contrast-to-noise ratio (CNR) were calculated. Subjective confidence was evaluated using a 3-point scale before looking at the nTE sequences (1 = very sure that I can identify a lesion and classify it, 2 = quite sure that I can identify a lesion and classify it, 3 = definitely want to see nTE for final assessment) and the subjective image quality of all examinations was evaluated using a four-grade scale (1 = sharp, 2 = slight blur, 3 = moderate blur and 4 = severe blur/not evaluable) for lesion and skin sharpness. Lesion morphology and contrast enhancement were also evaluated. With minTE sequences, no lesion was rated with ''definitely want to see nTE sequences for final assessment''. The difference of the longitudinal and transverse diameter did not differ significantly (p>0.05). With minTE, lesions and skin were rated to be significantly more blurry (p<0.01 for lesions and p<0.05 for skin). There was no difference between both sequences with respect to SNR, CNR, lesion morphology, contrast enhancement and detection of multifocal disease. Dynamic breast MRI with a minTE protocol is feasible without a major loss of information (SNR, CNR, lesion morphology, contrast enhancement and lesion sizes) and the temporal resolution can be increased by a factor of 2 using minTE sequences.

  3. Breast MRI at very short TE (minTE). Image analysis of minTE sequences on non-fat-saturated, subtracted T1-weighted images

    Energy Technology Data Exchange (ETDEWEB)

    Wenkel, Evelyn; Janka, Rolf; Kaemmerer, Nadine; Uder, Michael; Hammon, Matthias; Brand, Michael [Univ. Hospital Erlangen (Germany). Dept. of Radiology; Geppert, Christian [Siemens Healthcare GmbH, Erlangen (Germany); Hartmann, Arndt [Univ. Hospital Erlangen (Germany). Dept. of Pathology

    2017-02-15

    The aim was to evaluate a minimum echo time (minTE) protocol for breast magnetic resonance imaging (MRI) in patients with breast lesions compared to a standard TE (nTE) time protocol. Breasts of 144 women were examined with a 1.5 Tesla MRI scanner. Additionally to the standard gradient-echo sequence with nTE (4.8 ms), a variant with minimum TE (1.2 ms) was used in an interleaved fashion which leads to a better temporal resolution and should reduce the scan time by approximately 50%. Lesion sizes were measured and the signal-to-noise ratio (SNR) as well as the contrast-to-noise ratio (CNR) were calculated. Subjective confidence was evaluated using a 3-point scale before looking at the nTE sequences (1 = very sure that I can identify a lesion and classify it, 2 = quite sure that I can identify a lesion and classify it, 3 = definitely want to see nTE for final assessment) and the subjective image quality of all examinations was evaluated using a four-grade scale (1 = sharp, 2 = slight blur, 3 = moderate blur and 4 = severe blur/not evaluable) for lesion and skin sharpness. Lesion morphology and contrast enhancement were also evaluated. With minTE sequences, no lesion was rated with ''definitely want to see nTE sequences for final assessment''. The difference of the longitudinal and transverse diameter did not differ significantly (p>0.05). With minTE, lesions and skin were rated to be significantly more blurry (p<0.01 for lesions and p<0.05 for skin). There was no difference between both sequences with respect to SNR, CNR, lesion morphology, contrast enhancement and detection of multifocal disease. Dynamic breast MRI with a minTE protocol is feasible without a major loss of information (SNR, CNR, lesion morphology, contrast enhancement and lesion sizes) and the temporal resolution can be increased by a factor of 2 using minTE sequences.

  4. Reintroducing Maori ethnomathematical activities into the classroom: traditional Maori spatial orientation concepts

    Directory of Open Access Journals (Sweden)

    Tony Trinick

    2015-01-01

    Full Text Available Las practicas matemáticas maoríes fueron excluidas de la escolarización en Aotearoa / Nueva Zelanda durante más de 150 años, como resultado de las políticas explícitas que impiden el uso de la lengua y cultura indígena. Como consecuencia de la gama de políticas asimilacionistas, para la década de 1970, el idioma maorí fue considerado en peligro de extinción. En respuesta a la peligrosa situación de la lengua, las comunidades maoríes crearon sus propias escuelas, en un principio fuera del sistema estatal, para apoyar la revitalización de la lengua y la cultura. Sin embargo, la reintroducción de los conocimientos culturales en áreas como las matemáticas no ha igualado los esfuerzos de revitalización del idioma. Muchas prácticas etnomatemáticas originales ya no son de uso general en la comunidad indígena y las prácticas valoradas por la mayoría de Europa siguen siendo la norma en los programas escolares exigidos por el estado. Orientación espacial es un ejemplo del contenido de los planes de estudio de matemáticas que se basa en perspectivas matemáticas occidentales. Para proporcionar una perspectiva maorí, este documento se basa en entrevistas con los ancianos y los datos históricos para examinar términos de orientación espacial maoríes y los marcos espaciales de las referencias que se derivan de estos. Los estudiantes en una escuela Māori-medium school fueron probados en su comprensión de su conocimiento tradicional. Como consecuencia de ello, una serie de actividades de aprendizaje basadas en conceptos maoríes de orientación espacial se desarrolló y probó. Los resultados de estas actividades de aprendizaje mostraron el aumento de algunos entendimientos sobre conceptos maoríes de orientación espacial.

  5. A Direct TeX-to-Braille Transcribing Method

    Science.gov (United States)

    Papasalouros, Andreas; Tsolomitis, Antonis

    2017-01-01

    The TeX/LaTeX typesetting system is the most wide-spread system for creating documents in Mathematics and Science. However, no reliable tool exists to this day for automatically transcribing documents from the above formats into Braille/Nemeth code. Thus, visually impaired students of related fields do not have access to the bulk of study material…

  6. Characterization and photoluminescence studies of CdTe ...

    Indian Academy of Sciences (India)

    Administrator

    Abstract. The major objective of this work was to detect the change of photoluminescence (PL) intensity of. CdTe nanoparticles (NPs) before and after transfer from liquid phase to polystyrene (PS) matrix by electro- spinning technique. Thio-stabilized CdTe NPs were first synthesized in aqueous, then enwrapped by cetyl-.

  7. The mixing enthalpy of the Pb-Te system

    International Nuclear Information System (INIS)

    Blachnik, R.; Gather, B.

    1983-01-01

    The thermodynamic properties of molten Pb-Te alloys were measured at 1210 K in a Setaram-Calvet-type calorimeter. It was found that the enthalpy of mixing has a pronounced minimum of -26250 +- 950 J mol - 1 at 52 mol.%Te. The results obtained are discussed in terms of an ionic model. (Auth.)

  8. die geskiedenis van die saw gedenkteken te fort klapperkop militere ...

    African Journals Online (AJOL)

    As gevolg van enige optrede, op enige plek, te enige tyd, deur enige vyand van die RSA of deur enige terroris(te), insurgent(e) of ander persoon of persone wat die RSA en sy volkere kwaadgesind is. h. Binne twee jaar (vyfhondred-en-dertig dae) nadat hy/sy met 'n ongeskiktheids- pensioen uit diens getree het agv siekte,.

  9. Het optimale pluktijdstip is te voorspellen : rode bessen

    NARCIS (Netherlands)

    Westra, E.H.; Verschoor, J.A.

    2010-01-01

    Voor de lange bewaring van rode bessen moeten telers op het juiste moment plukken. Te vroeg oogsten geeft uitval door rot. Wageningen UR Food & Biobased Research (voorheen AFSG) ontwikkelde een voorspellingsmodel om het optimale pluktijdstip te kunnen bepalen op basis van de temperatuur in de

  10. Installing fonts in LaTeX a user's experience

    NARCIS (Netherlands)

    Hanssen, F.T.Y.

    2003-01-01

    This paper presents a user's experience with installing fonts for use in LaTeX. It will be shown that it is not hard to make a standard Type 1 font work, if you use modern font installation software for LaTeX. All the steps necessary to install the example fonts will be shown. The example fonts used

  11. Betrouwbaar toetsen op Afstand: Auteurschap. TeSLA docent workshop

    NARCIS (Netherlands)

    Brouns, Francis; Janssen, José

    2018-01-01

    In de workshop wordt ingegaan op technologie die ingezet kan worden om toetsen op afstand betrouwbaar af te nemen door instrumenten en technologie in te zetten voor vaststellen van identiteit van persoon en auteurschap van product. Uitgelegd wordt hoe dit in yOUlearn ingezet kan worden in het kader

  12. TeSLA presentatie voor medewerkers van AMN

    NARCIS (Netherlands)

    Janssen, José

    2017-01-01

    Presentatie over Online toetsen voor medewerkers van AMN (www.amn.nl). Topics: assessment onderzoek Welten-instituut en meer in het bijzonder het TeSLA project waarin instrumenten voor authenticatie en auteurschap verificatie worden gecombineerd om betrouwbaar toetsen op afstand mogelijk te maken.

  13. TeSLA pilot 2 pedagogical & quality aspects

    OpenAIRE

    Janssen, José

    2018-01-01

    Presentation given at the TeSLA project meeting at the Open University of the Netherlands, addressing pedagogical aspects of pilot 2 and clarification of the scope and limitations of the TeSLA instruments with respect to pedagogy, assessment activity and type of academic dishonesty.

  14. High thermoelectric potential of Bi{sub 2}Te{sub 3} alloyed GeTe-rich phases

    Energy Technology Data Exchange (ETDEWEB)

    Madar, Naor; Givon, Tom; Mogilyansky, Dmitry; Gelbstein, Yaniv [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva (Israel)

    2016-07-21

    In an attempt to reduce our reliance on fossil fuels, associated with severe environmental effects, the current research is focused on the identification of the thermoelectric potential of p-type (GeTe){sub 1−x}(Bi{sub 2}Te{sub 3}){sub x} alloys, with x values of up to 20%. Higher solubility limit of Bi{sub 2}Te{sub 3} in GeTe, than previously reported, was identified around ∼9%, extending the doping potential of GeTe by the Bi{sub 2}Te{sub 3} donor dopant, for an effective compensation of the high inherent hole concentration of GeTe toward thermoelectrically optimal values. Around the solubility limit of 9%, an electronic optimization resulted in an impressive maximal thermoelectric figure of merit, ZT, of ∼1.55 at ∼410 °C, which is one of the highest ever reported for any p-type GeTe-rich alloys. Beyond the solubility limit, a Fermi Level Pinning effect of stabilizing the Seebeck coefficient was observed in the x = 12%–17% range, leading to stabilization of the maximal ZTs over an extended temperature range; an effect that was associated with the potential of the governed highly symmetric Ge{sub 8}Bi{sub 2}Te{sub 11} and Ge{sub 4}Bi{sub 2}Te{sub 7} phases to create high valence band degeneracy with several bands and multiple hole pockets on the Fermi surface. At this compositional range, co-doping with additional dopants, creating shallow impurity levels (in contrast to the deep lying level created by Bi{sub 2}Te{sub 3}), was suggested for further electronic optimization of the thermoelectric properties.

  15. Diffusion and influence of Cu on properties of CdTe thin films and CdTe/CdS cells

    Energy Technology Data Exchange (ETDEWEB)

    Dzhafarov, T.D.; Yesilkaya, S.S.; Yilmaz Canli, N.; Caliskan, M. [Department of Physics, Yildiz Technical University, Davutpasa, 34210 Istanbul (Turkey)

    2005-01-31

    The effective diffusion coefficients of Cu for thermal and photodiffusion in the CdTe films have been estimated from resistivity versus duration of thermal or photoannealing curves. In the temperature range 60-200{sup o}C the effective coefficient of thermal diffusion (D{sub t}) and photodiffusion (D{sub ph}) are described as D{sub t}=7.3x10{sup -7}exp(-0.33/kT) and D{sub ph}=4.7x10{sup -8}exp(-0.20/kT). It is found that the diffusion doping of CdTe thin films by Cu at 400{sup o}C results in a sharp decrease of resistivity up to 7 orders of magnitude of p-type material, depending on thickness of Cu film. The comparative study of performance of CdTe(Cu)/CdS and CdTe/CdS cells has been studied. It is shown that the diffusion doping of CdTe film by Cu increases efficiency of CdTe(Cu)/CdS cells from 0.9% to 6.8%. The degradation of photovoltaic parameters of CdTe(Cu)/CdS cell, during testing under forward and reverse bias at room temperature, proceeds at a larger rate than those of CdTe/CdS cell without Cu. The degradation of performance of CdTe(Cu)/CdS cells is tentatively assigned to electrodiffusion of Cu in CdTe, resulting in redistribution of concentration of Cu-related centers in CdTe film and heterojunction region.

  16. Forenzika elektronske pošte

    Directory of Open Access Journals (Sweden)

    Milorad S. Markagić

    2013-10-01

    Full Text Available U najopštijem smislu digitalna forenzika može se definisati kao skup metoda za prikupljanje, analizu i prezentaciju digitalnih dokaza koji se mogu pronaći na računarima, serverima, u računarskim mrežama, bazama podataka, mobilnim uređajima i svim drugim elektronskim uređajima na kojima se čuvaju podaci. U ovom radu su opisane metode prikupljanja digitalnih dokaza u elektronskoj pošti i njihova analiza. Uvod Elektronska pošta se kao dokazni materijal pojavljuje u velikom broju kako građanskih tako i kriminalnih forenzičkih istraga. Elektronska pošta i elektronska pošta zasnovana na internet serverima  širi se veoma brzo, pa lako i brzo završi i na računaru korisnika kome nije namenjena. Prvu elektronsku poruku poslao je Ray Tomilson 1971. godine, a deset godina kasnije u kombinaciji sa personalnim računarima i internetom prerasta u globalni način komuniciranja i personalnog i poslovnog. Takođe se koristi i u svrhu zabave, načina razmene podataka, ali predstavlja i nezamenjiv izvor digitalnih dokaza, kada dodje do računarskog incidenta. Analiza elektronske pošte Svaka elektronska poruka sastoji se od dva dela: zaglavlja i teksta poruke. Iz zaglavlja je moguće saznati izvorišnu i odredišnu adresu, pošiljaoca i namenjenog primaoca, a telo poruke sadrži tekst poruke. Ekstenzije dokumenata elektronske pošte U slučajevima kada je potrebno otkriti samo dokumente potrebne za pregled elektronskih poruka, ili kopirati pojedinačni dokument sačuvan unutar elektronske pošte, moguće je koristiti sistem na istraživanom računaru ili specijalizovani softver kao što je Outlook Extract Pro ili Outlook Export. Mnogo ispravniji, sigurniji i jednostavniji način je korišćenje forenzičkih alata kao što su EnCase ili FTK, sa ugrađenim pregledačima koji omogućavaju pregled i snimanje sadržaja baze podataka kao i njihovo kopiranje na druge medije za dalju analizu. Forenzički alati automatizuju proces skidanja i kopiranja

  17. The excess enthalpies of liquid Ge-Pb-Te alloys

    International Nuclear Information System (INIS)

    Blachnik, R.; Binder, J.; Schlieper, A.

    1997-01-01

    The excess enthalpies of liquid alloys in the ternary system Ge-Pb-Te were determined at 1210 K in a heat flow calorimeter for five sections Ge y Pb 1-y -Te with y = 0.2, 0.4, 0.5, 0.6 and 0.8 and at 1153 K for Ge 0.5 Pb 0.5 -Te. The enthalpy surface in the ternary system is determined by a valley of exothermic minima, stretching from an exothermic minimum at the composition GeTe to one at the composition PbTe in the respective binaries. The excess enthalpies in the limiting metallic binary were adapted with the Redlich-Kister formalism. For the description of the thermodynamic functions in the ternary system the equation of Bonnier was taken using ternary coefficients. The calculated curves are in good agreement with the experimental data. (orig.)

  18. Slow Auger Relaxation in HgTe Colloidal Quantum Dots.

    Science.gov (United States)

    Melnychuk, Christopher; Guyot-Sionnest, Philippe

    2018-05-03

    The biexciton lifetimes in HgTe colloidal quantum dots are measured as a function of particle size. Samples produced by two synthetic methods, leading to partially aggregated or well-dispersed particles, exhibit markedly different dynamics. The relaxation characteristics of partially aggregated HgTe inhibit reliable determinations of the Auger lifetime. In well-dispersed HgTe quantum dots, the biexciton lifetime increases approximately linearly with particle volume, confirming trends observed in other systems. The extracted Auger coefficient is three orders of magnitude smaller than that for bulk HgCdTe materials with similar energy gaps. We discuss these findings in the context of understanding Auger relaxation in quantum-confined systems and their relevance to mid-infrared optoelectronic devices based on HgTe colloidal quantum dots.

  19. Crystal growth and characterization of Ir-Te compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kurzhals, Philipp; Weber, Frank; Zocco, Diego; Adelmann, Peter; Merz, Michael; Wolf, Thomas; Kuntz, Sebastian; Grube, Kai [Karlsruhe Institute of Technology, Institute for Solid State Physics, Karlsruhe (Germany)

    2016-07-01

    IrTe{sub 2} is distinguished by a structural phase transition whose origin is not understood up to the present day. We grew crystals using the self-flux method starting from the reagents iridium and tellurium and got specimen with varying amounts of IrTe{sub 2} and Ir{sub 3}Te{sub 8}, analyzed by x-ray powder diffraction. We studied the transition near T = 280 K in magnetization measurements down to T = 1.8 K probing also for superconductivity, which was reported for intercalated samples. Results indicate that the structural transition happens over an extended range in temperature and superconductivity is absent in our samples. Ir{sub 3}Te{sub 8} is not studied to such an extent as IrTe{sub 2}. In previous publications a structural phase transition is reported. We characterized the transition by performing magnetization measurements and X-ray diffraction.

  20. Phase transformation in Mg—Sb3Te thin films

    International Nuclear Information System (INIS)

    Li Jun-Jian; Chen Yi-Min; Nie Qiu-Hua; Lü Ye-Gang; Wang Guo-Xiang; Shen Xiang; Dai Shi-Xun; Xu Tie-Feng

    2014-01-01

    Mg-doped Sb 3 Te films are proposed to improve the performance of phase-change memory (PCM). We prepare Mg-doped Sb 3 Te films and investigate their crystallization behaviors, structural, optical and electrical properties. We find that Mg-doping can increase the crystallization temperature, enhance the activation energy, and improve the 10-year data retention of Sb 3 Te. Especially Mg 25.19 (Sb 3 Te)74.81 shows higher T c (∼ 190 °C) and larger E a (∼ 3.49 eV), which results in a better data retention maintaining for 10 yr at ∼ 112 °C. Moreover R a /R c value is also improved. These excellent properties make Mg—Sb—Te material a promising candidate for the phase-change memory (PCM). (special topic — international conference on nanoscience and technology, china 2013)

  1. Rashba split surface states in BiTeBr

    International Nuclear Information System (INIS)

    Eremeev, S V; Rusinov, I P; Nechaev, I A; Chulkov, E V

    2013-01-01

    Within density functional theory, we study the bulk band structure and surface states of BiTeBr. We consider both ordered and disordered phases, which differ in atomic order in the Te–Br sublattice. On the basis of relativistic ab initio calculations, we show that the ordered BiTeBr is energetically preferable as compared with the disordered one. We demonstrate that both Te- and Br-terminated surfaces of the ordered BiTeBr hold surface states with a giant spin–orbit splitting. The Te-terminated surface-state spin splitting has Rashba-type behavior with the coupling parameter α R ∼ 2 eVÅ. (paper)

  2. On the cesium-rich part of the Cs-Te phase diagram

    International Nuclear Information System (INIS)

    Boer, R. de; Cordfunke, E.H.P.

    1995-03-01

    The cesium-tellurium system in the region between 33 and 55 at.% Te has been investigated with X-ray diffraction and DSC. The existence of the compounds Cs 5 Te 3 and CsTe is demonstrated. The latter compound exhibits a structural transition at elevated temperature, as does the compound Cs 2 Te. The earlier reported compounds Cs 3 Te 2 and Cs 5 Te 4 do not exist. (orig.)

  3. Development of CdTe/Cd1-xMgxTe double barrier, single quantum well heterostructure for resonant tunneling

    International Nuclear Information System (INIS)

    Reuscher, G.; Keim, M.; Fischer, F.; Waag, A.; Landwehr, G.

    1995-01-01

    We report the first observation of resonant tunneling through a CdTe/Cd 1-x Mg x Te double barrier, single quantum well heterostructure. Negative differential resistance is observable at temperatures below 230 K, exhibiting a peak to valley ratio of 3:1 at 4.2 K. (author)

  4. First-principles study of lattice thermal conductivity in ZrTe5 and HfTe5

    Science.gov (United States)

    Wang, Cong; Wang, Haifeng; Chen, Y. B.; Yao, Shu-Hua; Zhou, Jian

    2018-05-01

    Recently, the layered transition-metal pentatellurides ZrTe5 and HfTe5 have attracted increasing attention because of their interesting topological electronic properties. Nevertheless, some of their other good physical properties seem to be ignored now. Actually, both ZrTe5 and HfTe5 have high electric conductivities (>105 Ω-1 m-1) and Seebeck coefficients (> 100 μV/K) at room temperature, thus making them promising thermoelectric materials. However, the disadvantage is that the thermal conductivities of the two materials are relatively high according to the few available experiments; meanwhile, the detailed mechanism of the intrinsic thermal conductivity has not been studied yet. Based on the density functional theory and the Boltzmann transport theory, we present here the theoretical study of the intrinsic lattice thermal conductivities of ZrTe5 and HfTe5, which are found to be in the range of 5-8 W/mṡK at room temperature and well consistent with the experimental results. We also find that the thermal conductivities of the two materials are anisotropic, which are mainly caused by their anisotropic crystal structures. Based on the detailed analysis, we proposed that the thermal conductivities of the two materials could possibly be reduced by different kinds of structural engineering at the atomic and mesoscopic scales, such as alloying, doping, nano-structuring, and polycrystalline structuring, which could make ZrTe5 and HfTe5 good thermoelectric materials for room temperature thermoelectric applications.

  5. Performance optimization of CdTe and CdZnTe detectors for γ-spectrometry

    International Nuclear Information System (INIS)

    Montemont, Guillaume

    2000-01-01

    This study deals with room-temperature gamma spectrometry with CdTe and CdZnTe semiconductor detectors. The aim was the improvement of energy resolution and detection efficiency. Some different phenomena have been investigated. Electronic noise knowledge has enabled us to optimize the design of filtering. Charge transport induces signal shape uncertainty and the processing circuit has been adapted in order to account for these variations. Study and simulation of electrical current induction process has permitted the development of a new Frisch-grid based detection structure. We have reached 3% energy resolutions at 122 keV without detection efficiency loss. Finally, the remaining limits of detector performances have been estimated by focusing on gamma interaction phenomena and material non-uniformity problems. (author) [fr

  6. Magnetospectroscopy of double HgTe/CdHgTe quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Bovkun, L. S.; Krishtopenko, S. S.; Ikonnikov, A. V., E-mail: antikon@ipmras.ru; Aleshkin, V. Ya.; Kadykov, A. M. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Ruffenach, S.; Consejo, C.; Teppe, F.; Knap, W. [Laboratoire Charles Coulomb (L2C), UMR CNRS 5221 and UM (France); Orlita, M.; Piot, B.; Potemski, M. [Laboratoire National des Champs Magnetiques Intenses (LNCMI-G), CNRS-UJF-UPS-INSA (France); Mikhailov, N. N.; Dvoretskii, S. A. [Russian Academy of Sciences, Siberian Branch, Rzhanov Institute of Semiconductor Physics (Russian Federation); Gavrilenko, V. I. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2016-11-15

    The magnetoabsorption spectra in double HgTe/CdHgTe quantum wells (QWs) with normal and inverted band structures are investigated. The Landau levels in symmetric QWs with a rectangular potential profile are calculated based on the Kane 8 × 8 model. The presence of a tunnel-transparent barrier is shown to lead to the splitting of states and “doubling” of the main magnetoabsorption lines. At a QW width close to the critical one the presence of band inversion and the emergence of a gapless band structure, similar to bilayer graphene, are shown for a structure with a single QW. The shift of magnetoabsorption lines as the carrier concentration changes due to the persistent photoconductivity effect associated with a change in the potential profile because of trap charge exchange is detected. This opens up the possibility for controlling topological phase transitions in such structures.

  7. BOREAS TE-9 NSA Canopy Biochemistry

    Science.gov (United States)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Margolis, Hank; Charest, Martin; Sy, Mikailou

    2000-01-01

    The BOREAS TE-9 team collected several data sets related to chemical and photosynthetic properties of leaves. This data set contains canopy biochemistry data collected in 1994 in the NSA at the YJP, OJR, OBS, UBS, and OA sites, including biochemistry lignin, nitrogen, cellulose, starch, and fiber concentrations. These data were collected to study the spatial and temporal changes in the canopy biochemistry of boreal forest cover types and how a high-resolution radiative transfer model in the mid-infrared could be applied in an effort to obtain better estimates of canopy biochemical properties using remote sensing. The data are available in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  8. Leptogenesis with TeV Scale WR

    Science.gov (United States)

    Gu, Pei-Hong; Mohapatra, Rabindra N.

    2018-04-01

    Successful leptogenesis within the conventional TeV-scale left-right implementation of type-I seesaw has been shown to require that the mass of the right-handed WR± boson should have a lower bound much above the reach of the Large Hadron Collider. This bound arises from the necessity to suppress the washout of lepton asymmetry due to WR±-mediated Δ L ≠0 processes. We show that in an alternative quark seesaw realization of left-right symmetry, the above bound can be avoided. Lepton asymmetry in this model is generated not via the usual right-handed neutrino decay but rather via the decay of new heavy scalars producing an asymmetry in the B -L carrying Higgs triplets responsible for type-II seesaw, whose decay leads to the lepton asymmetry.

  9. BOREAS TE-9 NSA Photosynthetic Response Data

    Science.gov (United States)

    Hall, Forrest G.; Curd, Shelaine (Editor); Dang, Qinglai; Margolis, Hank; Coyea, Marie

    2000-01-01

    The Boreal Ecosystem-Atmospheric Study (BOREAS) TE-9 (Terrestrial Ecology) team collected several data sets related to chemical and photosynthetic properties of leaves. This data set describes: (1) the response of leaf and shoot-level photosynthesis to ambient and intercellular CO2 concentration, temperature, and incident photosynthetically active radiation (PAR) for black spruce, jack pine, and aspen during the three intensive field campaigns (IFCs) in 1994 in the Northern Study Area (NSA); (2) the response of stomatal conductance to vapor pressure difference throughout the growing season of 1994; and (3) a range of shoot water potentials (controlled in the laboratory) for black spruce and jack pine. The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  10. Electronic structure of Fe1.08Te bulk crystals and epitaxial FeTe thin films on Bi2Te3

    Science.gov (United States)

    Arnold, Fabian; Warmuth, Jonas; Michiardi, Matteo; Fikáček, Jan; Bianchi, Marco; Hu, Jin; Mao, Zhiqiang; Miwa, Jill; Singh, Udai Raj; Bremholm, Martin; Wiesendanger, Roland; Honolka, Jan; Wehling, Tim; Wiebe, Jens; Hofmann, Philip

    2018-02-01

    The electronic structure of thin films of FeTe grown on Bi2Te3 is investigated using angle-resolved photoemission spectroscopy, scanning tunneling microscopy and first principles calculations. As a comparison, data from cleaved bulk Fe1.08Te taken under the same experimental conditions is also presented. Due to the substrate and thin film symmetry, FeTe thin films grow on Bi2Te3 in three domains, rotated by 0°, 120°, and 240°. This results in a superposition of photoemission intensity from the domains, complicating the analysis. However, by combining bulk and thin film data, it is possible to partly disentangle the contributions from three domains. We find a close similarity between thin film and bulk electronic structure and an overall good agreement with first principles calculations, assuming a p-doping shift of 65 meV for the bulk and a renormalization factor of around two. By tracking the change of substrate electronic structure upon film growth, we find indications of an electron transfer from the FeTe film to the substrate. No significant change of the film’s electronic structure or doping is observed when alkali atoms are dosed onto the surface. This is ascribed to the film’s high density of states at the Fermi energy. This behavior is also supported by the ab initio calculations.

  11. Determination of K shell fluorescence cross-section and Kβ/Kα intensity ratios for Fe, Se, Te, FeSe, FeTe and TeSe

    International Nuclear Information System (INIS)

    Saydam, M.; Aksoy, C.; Cengiz, E.; Alaşalvar, C.; Tıraşoğlu, E.; Apaydın, G.

    2012-01-01

    The fluorescence cross-sections (σ Ki ) and the intensity ratios K β /K α for pure Fe, Se, Te elements and FeSe, FeTe, TeSe complexes have been investigated. The samples were excited by 59.5 keV γ-rays from 241 Am annular radioactive source and emitted X-rays. They were counted by an Ultra-LEGe detector with resolution of 150 eV at 5.9 keV. For pure elements results have been compared with the theoretical calculated values. According to our results band length and mutual interaction of atoms affected the results. We claimed that these effects would help researchers who study on superconductors, especially determining which compound can be show the superconductor properties. - Highlights: ► TeSe, FeSe and FeTe complexes have affected each other in terms of charge transfer. ► Fe excitement and enhancement have been made by Se and Te. ► Attractive interactions between electrons can help to becoming superconductivity.

  12. Fundamentos teóricos para el cálculo de los parámetros técnicos de las líneas eléctricas aéreas de baja tensión para su uso en telecomunicaciones

    Directory of Open Access Journals (Sweden)

    Henry Arturo Bastidas Mora

    2009-05-01

    Full Text Available Este artículo presenta las propiedades de las redes de energía eléctrica para su utilización como canales para la transmisión de señales de telecomunicaciones. Comienza explorando los principios y fundamentos teóricos para el cálculo de los parámetros técnicos críticos de las líneas eléctricas, por lo que trata con detalle lo referente a los parámetros primarios: inductancia, capaci- tancia, conductancia y resistencia, y, asociados a estos, los parámetros secundarios (más útiles desde el punto de vista de las te- lecomunicaciones: impedancia característica y constante de propagación; de esta última, su componente real, la constante de atenuación. Se verifican las diversas topologías y la estructura de los sistemas eléctricos de potencia para líneas de media y baja tensión aéreas y se propone un modelo matemático para analizar su comportamiento a altas frecuencias extensible a la mayoría de los sistemas de distribución aéreos de energía eléctrica colombianos. El trabajo incluye una parte de los resultados de la in- vestigación denominada “Diseño de una solución a través de la tecnología PLT (Power Line Telecommunications para acceso a Internet de banda ancha en regiones rurales de Colombia”, realizada por el autor con la Universidad Piloto de Colombia. Me- diante la utilización del modelo matemático propuesto se tiene una herramienta teórica de una parte de los cálculos aplicables a PLT.

  13. Electric transport properties of the pentatelluride materials HfTe{sub 5} and ZrTe{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Tritt, T M; Wilson, M L; Littleton, R L [and others

    1997-07-01

    The authors have measured the resistivity and thermopower of single crystals as well as polycrystalline pressed powders of the low-dimensional pentatelluride materials: HfTe{sub 5} and ZrTe{sub 5}. They have performed these measurements as a function of temperature between 5K and 320K. In the single crystals there is a peak in the resistivity for both materials at a peak temperature, T{sub p} where T{sub p} {approx} 80K for HfTe{sub 5} and T{sub p} {approx} 145K for ZrTe{sub 5}. Both materials exhibit a large p-type thermopower around room temperature which undergoes a change to n-type below the peak. These data are similar to behavior observed previously in these materials. They have also synthesized pressed powders of polycrystalline pentatelluride materials, HfTe{sub 5} and ZrTe{sub 5}. They have measured the resistivity and thermopower of these polycrystalline materials as a function of temperature between 5K and 320K. For the polycrystalline material, the room temperature thermopower for each of these materials is relatively high, +95 {micro}V/K and +65 {micro}V/K for HfTe{sub 5} and ZrTe{sub 5}, respectively. These values compare closely to thermopower values for single crystals of these materials. At 77 K, the thermopower is +55 {micro}V/K for HfTe{sub 5} and +35 {micro}V/K for ZrTe{sub 5}. In fact, the thermopower for the polycrystals decreases monotonically with temperature to T {approx} 5K, thus exhibiting p-type behavior over the entire range of temperature. As expected, the resistivity for the polycrystals is higher than the single crystal material, with values of 430 m{Omega}-cm and 24 m{Omega}-cm for HfTe{sub 5} and ZrTe{sub 5} respectively, compared to single crystal values of 0.35 m{Omega}-cm (HfTe{sub 5}) and 1.0 m{Omega}-cm (ZrTe{sub 5}). The authors have found that the peak in the resistivity evident in both single crystal materials is absent in these polycrystalline materials. They will discuss these materials in relation to their potential as

  14. Thermoelectric properties of Bi2Te3 base solid solutions in the Bi2Te3-InS system

    International Nuclear Information System (INIS)

    Safarov, M.G.; Rustamov, P.G.; Alidzhanov, M.A.

    1979-01-01

    The rich Bi 2 Te 3 part ot the Bi 2 Te 3 -InS constitutional diagram has been studied with a view to produce new Bi 2 Te 3 -based solid solutions and to establish the maximum solubility of InS in Bi 2 Te 3 . The methods of differential-thermal, X-ray phase and microstructural analysis have been used. The alloys microhardness, density and thermal electric properties have been measured. A large region of Bi 2 Te 3 -based restricted solid solutions has been detected; it reaches 14.0 mol.% InS at room temperature. Studied have been the thermoelectromotive forces, electric and thermal conductivity of the alloys, containing up to 5 mol.% InS in the 300-700 K temperature range

  15. Study of CdTe and HgCdTe thin films obtained by electrochemical methods

    International Nuclear Information System (INIS)

    Guillen, C.

    1990-01-01

    Cadmium telluride polycrystalline thin films were fabricated on SnO 2 -coated glass substrates by potentiostatic electrodeposition and characterized by X-ray diffraction, energy dispersive X-ray analyses (EDAX), optical and electrical measurements. The films dseposited at potentials more positive than -0.65 V vs.SCE were p-type but those deposited at more negative potentials were n-type. All CdTe thin films showed a band-gap energy about 1.45 eV and a large absorption coeffici-ent (a=10 5 cm -1 ) above de band edge. The addition of even small amounts of mercury to the CdTe produces higuer conductivity values and lower band-gap energies. We have prepared HgCdTe thin films where the band-gap energies ranged between 0.93 and 0.88 eV depending on the ratio of mercury to cadmium. Heat treatment at 300 0 C increases the crystalline diameter and alter the composition of the electrodeposited films, a decrease of the resistivity values was also observed. (Author)

  16. Growth of CdTe: Al films; Crecimiento de peliculas de CdTe: Al

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez A, M.; Zapata T, M. [CICATA-IPN, 89600 Altamira, Tamaulipas (Mexico); Melendez L, M. [CINVESTAV-IPN, A.P. 14-740, 07000 Mexico D.F. (Mexico); Pena, J.L. [CINVESTAV-IPN, A.P. 73 Cordemex, 97310 Merida, Yucatan (Mexico)

    2006-07-01

    CdTe: AI films were grown by the close space vapor transport technique combined with free evaporation (CSVT-FE). The Aluminum (Al) evaporation was made by two kinds of sources: one made of graphite and the other of tantalum. The films were deposited on glass substrates. The Al source temperature was varied maintaining the CdTe source temperature fixed as well as the substrate temperature. The films were characterized by x-ray energy dispersive analysis (EDAX), x-ray diffraction and optical transmission. The results showed for the films grown with the graphite source for Al evaporation, the Al did not incorporate in the CdTe matrix, at least to the level of EDAX sensitivity; they maintained the same crystal structure and band gap. For the samples grown with the tantalum source, we were able to incorporate the Al. The x-ray diffraction patterns show that the films have a crystal structure that depends on Al concentration. They were cubic up to 2.16 at. % Al concentration; for 19.65 at. % we found a mixed phase; for Al concentration higher than 21 at. % the films were amorphous. For samples with cubic structure it was found that the lattice parameter decreases and the band gap increases with Al concentration. (Author)

  17. Zn2(TeO3)Br2

    Science.gov (United States)

    Zhang, Dong; Johnsson, Mats

    2008-01-01

    Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3)Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetra­hedra, and [TeO3 E] tetra­hedra (E being the 5s 2 lone pair of Te4+) joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3)Br2 is isostructural with the synthetic compounds Zn2(TeO3)Cl2, CuZn(TeO3)2, Co2(TeO3)Br2 and the mineral sophiite, Zn2(SeO3)Cl2. PMID:21202162

  18. Radiative and interfacial recombination in CdTe heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Swartz, C. H., E-mail: craig.swartz@txstate.edu; Edirisooriya, M.; LeBlanc, E. G.; Noriega, O. C.; Jayathilaka, P. A. R. D.; Ogedengbe, O. S.; Hancock, B. L.; Holtz, M.; Myers, T. H. [Materials Science, Engineering, and Commercialization Program, Texas State University, 601 University Dr., San Marcos, Texas 78666 (United States); Zaunbrecher, K. N. [National Renewable Energy Laboratory, 15013 Denver West Parkway, Mississippi RSF200, Golden, Colorado 80401 (United States)

    2014-12-01

    Double heterostructures (DH) were produced consisting of a CdTe film between two wide band gap barriers of CdMgTe alloy. A combined method was developed to quantify radiative and non-radiative recombination rates by examining the dependence of photoluminescence (PL) on both excitation intensity and time. The measured PL characteristics, and the interface state density extracted by modeling, indicate that the radiative efficiency of CdMgTe/CdTe DHs is comparable to that of AlGaAs/GaAs DHs, with interface state densities in the low 10{sup 10 }cm{sup −2} and carrier lifetimes as long as 240 ns. The radiative recombination coefficient of CdTe is found to be near 10{sup −10} cm{sup 3}s{sup −1}. CdTe film growth on bulk CdTe substrates resulted in a homoepitaxial interface layer with a high non-radiative recombination rate.

  19. Tamizaje fitoquímico y evaluación de la actividad antimicrobiana de los extractos alcohólico y etéreo de la semilla de Mammea americana de Ecuador

    Directory of Open Access Journals (Sweden)

    Patricia Manzano

    2016-06-01

    Full Text Available En  el  presente  trabajo  investigativo  se muestran  los  resultados del  tamizaje  fitoquímico  y la evaluación  del estudio de inhibición antimicrobiana  de los extractos  obtenidos de  la almendra  y policarpo  de la semilla de Mammea americana L (Mamey Cartagena del Ecuador. Los procesos de secado y molinado se realizaron por el método de Martínez (2000; el tarnizaje fitoquímico por el método de Miranda y Cuéllar (2000, mientras que la actividad inhibitoria se ensayó  mediante la prueba  de sensibilidad  por difusión  con discos (Winn,  2008. En el análisis  estadístico  para comprobar    la normalidad  de los  resultados  obtenidos    se utilizó    el  test  de Shapiro- Wilks  y Kruskal-Wallis  para determinar diferencias estadísticas entre los rangos de los tratamientos.  En el tamizaje fitoquímico   se   determinó   la  presencia   de   los   siguientes compuestos   químicos: aceites/grasas;   alcaloides;   flavonoides; quinonas;   saponinas;   lactonas;   azúcares/reductores   y taninos. El extracto alcohólico  mostró inhibición frente a Pseudomonas  spp, Salmonel1a spp y E. Coli; y, el extracto  etéreo inhibió  E.coli. Estos resultados  son los primeros   informados  para la especie ecuatoriana,    lo que  conlleva  a la  elaboración  de  una línea  base sólida  para  estudios posteriores.

  20. INCLUSIÓN DE HARINAS DE FOLLAJES ARBÓREOS Y ARBUSTIVOS TROPICALES (Morus alba, Erythrina poeppigiana, Tithonia diversifolia EHibiscus rosa-sinensis EN LA ALIMENTACIÓN DE CUYES (Cavia porcellus Linnaeus

    Directory of Open Access Journals (Sweden)

    G. A. Meza

    2014-01-01

    Full Text Available La investigación se ejecutó en la Finca Experimental “La María” propiedad de la Univer-sidad Técnica Estatal de Quevedo (UTEQ localizada en el km 71/2de la vía Quevedo-Mocache; Provincia de Los Ríos cuya ubicación geográfica de 1º 6’ 23” de latitud sury 79º 29’ 12” de longitud oeste y a una altura de 73 m.s.n.m. El objetivo principal fueevaluar el comportamiento productivo de cuyes con la inclusión del 20% de harinasderivadas de follajes arbustivos y arbóreos tropicales. Se utilizaron 40 cuyes macho de 30días de edad. Se empleó un diseño completamente al azar con cinco tratamientos, cuatroréplicas y la unidad experimental estuvo conformado por dos cuyes. Para determinarlas diferencias entre medias de tratamientos se aplicó la prueba de Tukey (P≤0.05. Seevaluaron cinco dietas-tratamientos: (T0 dieta 100% balanceado, (T1 80% dieta y 20%harina deMorus alba, (T2 80% dieta y 20% harina deErythrina poeppigiana, (T3 80%dieta y 20% harina deTithonia diversifolia, (T4 80% dieta y 20% harina deHibiscusrosa-sinensis. Las variables bajo estudio fueron: consumo de alimento de balanceado enmateria seca (CABMS, g, ganancia de peso (GP, g, índice de conversión alimenticia(ICA y rendimiento en canal (RC, %. La rentabilidad de los tratamientos se determinóa través de la relación beneficio-costo (R b/c. Los mayores (P<0.01 CABMS, GP-ICAy RC-Rentabilidad, la registraron los tratamientos: T0 (48.34 g MS animal-1d-1, T1(8.80 g animal-1d-1y 5.04 y el T3 (77.67% y 26.20%, respectivamente.

  1. Florística e estrutura do componente arbustivo-arbóreo de uma floresta higrófila da bacia do rio Jacaré-Pepira, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Marques Márcia C. M.

    2003-01-01

    Full Text Available As florestas higrófilas são formações ribeirinhas caracterizadas por ocorrerem em solo permanentemente encharcado e restritas a pequenos fragmentos junto a outros tipos vegetacionais. Neste trabalho caracterizaram-se a florística e a estrutura do componente arbustivo-arbóreo (plantas com DAP>5cm de uma área de 0,36ha de floresta higrófila localizada em Brotas (48º06'W 22º16'S, 470m.s.m., Estado de São Paulo, usando-se método de parcelas (total de 24 parcelas. No total foram amostrados 735 indivíduos, distribuídos em 32 famílias e 51 espécies. As espécies que se destacaram na comunidade devido aos elevados valores de importância foram Calophyllum brasiliense Camb., Protium almecega L. Marchand, Podocarpus sellowii Klotzch., Tapirira guianensis Aubl. e Dendropanax cuneatum DC. Decne. & Planch. O índice de diversidade de Shannon foi igual a 2,81, valor pouco superior aos descritos para florestas semelhantes. Na comunidade, as espécies generalistas com relação ao encharcamento do solo e as de solo drenado contribuíram na riqueza total (juntas 62% do total de espécies amostradas, enquanto as espécies de solo encharcado tiveram maior contribuição na composição da dominância (66% da dominância total e densidade (67% da densidade total relativas. A diversidade de situações topográficas e a entrada de espécies da vegetação do cerrado adjacente permitiram que espécies com diferentes exigências hídricas se estabelecessem na área relativamente pequena da floresta e influenciaram fortemente a florística e estrutura da comunidade.

  2. Notas sobre a composição arbóreo-arbustiva de uma fisionomia das savanas de Roraima, Amazônia Brasileira Notes on the woody composition of a vegetation physionomy of the Roraima's savannas, Brazilian Amazonia

    Directory of Open Access Journals (Sweden)

    Reinaldo Imbrozio Barbosa

    2005-06-01

    Full Text Available Foi realizado um inventário florístico das espécies arbóreo-arbustivas presentes em uma das unidades de vegetação que compõem a paisagem de savanas do Estado de Roraima, extremo norte da Amazônia brasileira. Esta unidade é caracterizada por ser densamente colonizada por ninhos do cupim Cornitermes ovatus Emerson. Foram observadas 29 espécies (15 famílias botânicas em três localidades utilizadas para a amostragem. O total de espécies, por localidade, variou de 12 a 20. As espécies mais abundantes foram Byrsonima verbascifolia (L. DC. e Mimosa microcephala Humb. & Bonpl. ex Willd. (subarbustivas, Byrsonima cf. intermedia A. Juss. e Randia formosa (Jack. K. Schum. (arbustivas e, Byrsonima crassifolia (L. H.B.K. e Curatella americana L. (arbóreas. Oito espécies são comuns às três localidades. A diversidade medida pelo Índice de Shannon (H' foi baixa para todos os locais amostrados (A floristic inventory of woody species was carried out in one of the vegetation units that compose the savannas landscape of the Roraima State, northernmost of Brazilian Amazonia. This unit is characterized by dense colonization of nests of termites Cornitermes ovatus Emerson. Twenty nine woody species were observed (15 botany families in three localities used for sampling. The total of species varied from 12 to 20 by locality. The most abundant species were Byrsonima verbascifolia (L. DC. and Mimosa microcephala Humb. & Bonpl. ex Willd. (dwarf shrubs, Byrsonima cf. intermedia A. Juss. and Randia formosa (Jack. K. Schum. (shrubby and, Byrsonima crassifolia (L. H.B.K. and Curatella americana L. (arboreal. Eight species are common to all localities. Diversity measured by the Index of Shannon (H' was low for all the areas sampled (<0.90 indicating high specimens concentration in few species. The Index of Sørensen indicated similarities (± 0.60 among studied areas, suggesting a group of landscapes with common plant diversity, representing a same

  3. Imagens de Alta Resolução Espacial de Veículos Aéreos Não Tripulados (VANT no Planejamento do Uso e Ocupação do Solo

    Directory of Open Access Journals (Sweden)

    Anny Keli Aparecida Alves Cândido

    2015-01-01

    Full Text Available A criação, aperfeiçoamento e uso de técnicas de sensoriamento remoto com foco em imagens suborbitais vêm aumentando, por apresentarem uma série de vantagens na análise geográfica e ecológica, produzindo dados com alta resolução espacial. O objetivo desse trabalho foi testar técnicas de classificação supervisionada e não supervisionada em imagens aéreas digitais de alta resolução espacial obtidas por veículo aéreo não tripulado (VANT, empregando dois softwares, SPRING e ArcGis. As imagens aéreas possuem resolução espacial de aproximadamente 10 cm, com área útil de recobrimento em torno de 45%. Foram obtidas em junho de 2011 e recobrem um trecho da cabeceira do rio São Lourenço, Campo Verde-MT. As fotografias aéreas foram georreferenciadas e posteriormente foram realizados os testes de classificação, dentre os quais apresentaram melhores resultados as classificações por região. Nessa etapa foram realizados aproximadamente 100 testes de segmentação com parâmetros de similaridade e área diferenciados, até encontrar uma rotina que melhor se adequasse a área de estudo. A classificação que melhor delimitou as diferentes feições presentes na imagem foi a supervisionada por região, cuja segmentação possuía 20 pixels de similaridade e 200 de área. Para comprovar estatisticamente a eficiência da classificação foi realizado teste de cluster e a validação foi realizada por meio do índice kappa e exatidão global. Os resultados apresentados assim como o uso de VANT, são ótimas ferramentas e passiveis de utilização em diversas áreas, incluindo rotina de perícia ambiental e monitoramento de recuperação de áreas degradadas, no âmbito do Código Florestal Brasileiro.

  4. Petrogenesis of the Yaochong granite and Mo deposit, Western Dabie orogen, eastern-central China: Constraints from zircon U-Pb and molybdenite Re-Os ages, whole-rock geochemistry and Sr-Nd-Pb-Hf isotopes

    Science.gov (United States)

    Chen, Wei; Xu, Zhaowen; Qiu, Wenhong; Li, Chao; Yu, Yang; Wang, Hao; Su, Yang

    2015-05-01

    The Dabie orogen is among the most famous continent-continent collisional orogenic belts in the world, and is characterized by intensive post-collisional extension, magmatism and Mo mineralization. However, the genetic links between the mineralization and the geodynamic evolution of the orogen remain unresolved. In this paper, the Yaochong Mo deposit and its associated granitic stocks were investigated to elucidate this issue. Our new zircon U-Pb ages yielded an Early Cretaceous age (133.3 ± 1.3 Ma) for the Yaochong granite, and our molybdenite Re-Os dating gave a similar age (135 ± 1 Ma) for the Mo deposit. The Yaochong stock is characterized by high silica and alkali but low Mg, Fe and Ca. It is enriched in light rare earth elements (LREEs) and large ion lithophile elements (LILEs: Rb, K, Th and U), but strongly depleted in heavy REEs, and high field strength elements (HFSEs: Nb, Ta, Ti and Y). The Yaochong granite has initial 87Sr/86Sr ratios of 0.7087-0.7096, and Pb isotopic ratios of (206Pb/204Pb)i = 16.599-16.704, (207Pb/204Pb)i = 15.170-15.618 and (208Pb/204Pb)i = 36.376-38.248. The granite has εNd(t) of -18.0 to -16.3 and εHf(t) values of -26.5 to -20.0. All these data indicate that the Yaochong granite is a high-K calc-alkaline fractionated I-type granite, and may have originated from partial melting of the thickened Yangtze continental crust. The Mo ores also show low radiogenic Pb isotopes similar to the Yaochong stock. Medium Re content in molybdenite (21.8-74.8 ppm) also suggests that the ore-forming materials were derived from the thickened lower crust with possibly minor mixing with the mantle. Similar to the Eastern Dabie orogen, the thickened crust beneath the Western Dabie orogen may also have experienced tectonic collapse, which may have exerted fundamental geodynamic controls on the two-stage Mo mineralization in the region.

  5. Reactivity of p53 protein in canine transmissible venereal tumor Reatividade da proteína P53 no tumor venéreo transmissível canino

    Directory of Open Access Journals (Sweden)

    J.V. Moro

    2010-04-01

    Full Text Available The expression of p53 protein was evaluated in canine transmissible venereal tumor (CTVT, as following: natural occurrence (n=8; resistant to chemotherapy (n=4; and allogeneic transplanted in progression (n=8, stable (n=8, and regression (n=8stages. The collected specimens were submitted to GM1 immunohistochemical reaction. Results showed a mean percentage of immunomarked cells around 18.6% in CTVT of natural occurrence, 23.8% in CTVT resistant to chemotherapy, 22.9% in allogeneic transplanted CTVT in both progression and stable stages, and 35.8% in transplanted CTVT in regression stage. The results suggest that there is a functional abnormality in p53 gene and its products in the studied tumors; although, it is not possible to correlate the percentage of cells marked by p53 and a prognosis.A expressão da proteína p53 foi avaliada em espécimes de tumor venéreo transmissível canino (TVT de ocorrência natural (n=8; resistente à quimioterapia (n=4 e transplantado em cão nas fases de progressão tumoral (n=8, de latência (n=8 e de regressão (n=8. Os espécimes foram submetidos à reação de imunoistoquímica. Os resultados mostraram porcentagem média de células imunomarcadas de 18,6% no TVT de ocorrência natural, de 23,8% no TVT refratário, 22,9% nos TVTs transplantados nas fases de progressão e latência e de 35,8% na fase de regressão. Os resultados sugerem que há uma anormalidade funcional no gene P53 e seus produtos nos tumores estudados, apesar de não ser possível correlacionar a porcentagem de células marcadas pelo p53 ao prognóstico.

  6. Detección de malas hierbas en girasol en fase temprana mediante imágenes tomadas con un vehículo aéreo no tripulado (UAV

    Directory of Open Access Journals (Sweden)

    J.M. Peña

    2014-12-01

    Full Text Available La discriminación de malas hierbas en fase temprana con técnicas de teledetección requiere imágenes remotas de muy elevada resolución espacial (píxeles <5 cm. Actualmente, sólo los vehículos aéreos no tripulados (UAV pueden generar este tipo de imágenes. El objetivo de este trabajo fue evaluar imágenes UAV tomadas con una cámara visible a diferentes alturas de vuelo (40, 60, 80 y 100 m y cuantificar la influencia de la resolución espacial en la discriminación de malas hierbas en fase temprana en un cultivo de girasol. Se aplicó un algoritmo de clasificación de imágenes basado en objetos, el cual se divide en dos fases principales: 1 detección de líneas de cultivo y 2 clasificación de cultivo, malas hierbas y suelo desnudo. El algoritmo resultó 100% eficaz en la detección de las líneas de cultivo en todos los casos (fase 1, así como en la detección de zonas libres de mala hierba en las imágenes tomadas a 40 y 60 m de altura. En las zonas con presencia de malas hierbas, los mejores resultados se obtuvieron en las imágenes tomadas a baja altura (40 m, con un 71% de marcos de muestreo clasificados correctamente (fase 2. La mayoría de los fallos de clasificación cometidos en todas las imágenes fueron falsos negativos, es decir, malas hierbas no detectadas debido a su pequeño tamaño en el momento de la captura de las imágenes. Por tanto, el siguiente paso sería desarrollar un estudio multitemporal para estudiar la detección de las malas hierbas en estados fenológicos más avanzados. Esto podría facilitar su discriminación en las imágenes y, por tanto, disminuir el porcentaje de falsos negativos en las clasificaciones.

  7. CdTe Photovoltaics for Sustainable Electricity Generation

    Science.gov (United States)

    Munshi, Amit; Sampath, Walajabad

    2016-09-01

    Thin film CdTe (cadmium telluride) is an important technology in the development of sustainable and affordable electricity generation. More than 10 GW of installations have been carried out using this technology around the globe. It has been demonstrated as a sustainable, green, renewable, affordable and abundant source of electricity. An advanced sublimation tool has been developed that allows highly controlled deposition of CdTe films onto commercial soda lime glass substrates. All deposition and treatment steps can be performed without breaking the vacuum within a single chamber in an inline process that can be conveniently scaled to a commercial process. In addition, an advanced cosublimation source has been developed to allow the deposition of ternary alloys such as Cd x Mg1- x Te to form an electron reflector layer which is expected to address the voltage deficits in current CdTe devices and to achieve very high efficiency. Extensive materials characterization, including but not limited to scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, high resolution transmission electron microscopy and electron back-scatter diffraction, has been performed to get a better understanding of the effects of processing conditions on CdTe thin film photovoltaics. This combined with computer modeling such as density function theory modeling gives a new insight into the mechanism of CdTe photovoltaic function. With all these efforts, CdTe photovoltaics has seen great progress in the last few years. Currently, it has been recorded as the cheapest source of electricity in the USA on a commercial scale, and further improvements are predicted to further reduce the cost while increasing its utilization. Here, we give an overview of the advantages of thin film CdTe photovoltaics as well as a brief review of the challenges that need to be addressed. Some fundamental studies of processing conditions for thin film CdTe are also presented

  8. Photostimulated changes of properties of CdTe films

    Energy Technology Data Exchange (ETDEWEB)

    Dzhafarov, T.D. [Institute of Physics, Azerbaijan National Academy of Sciences, AZ-1143 Baku (Azerbaijan); Yesilkaya, S.S. [Department of Physics, Yildiz Technical University, 34210 Esenler/Istanbul (Turkey)

    2007-08-15

    The effect of illumination during the close-spaced sublimation (CSS) growth on composition, structural, electrical, optical and photovoltaic properties of CdTe films and CdTe/CdS solar cells were investigated. Data on comparative study by using X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectra and conductivity-temperature measurements of CdTe films prepared by CSS method in dark (CSSD) and under illumination (CSSI) were presented. It is shown that the growth rate and the grain size of CdTe films grown under illumination is higher (by factor about of 1.5 and 3 respectively) than those for films prepared without illumination. The energy band gap of CdTe films fabricated by both technology, determined from absorption spectra, is same (about of 1.50 eV), however conductivity of the CdTe films produced by CSSI is considerably greater (by factor of 10{sup 7}) than that of films prepared by CSSD. The photovoltaic parameters of pCdTe/nCdS solar cells fabricated by photostimulated CSSI technology (J{sub sc}=28 mA/cm{sup 2}, V{sub oc}=0.63 V) are considerably larger than those for cells prepared by CSSD method (J{sub sc}=22 mA/cm{sup 2}, V{sub oc}=0.52 V). A mechanism of photostimulated changes of properties of CdTe films and improvement of photovoltaic parameters of CdTe/CdS solar cells is suggested. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Improved structural and electrical properties in native Sb2Te3/GexSb2Te3+x van der Waals superlattices due to intermixing mitigation

    Directory of Open Access Journals (Sweden)

    Stefano Cecchi

    2017-02-01

    Full Text Available Superlattices made of Sb2Te3/GeTe phase change materials have demonstrated outstanding performance with respect to GeSbTe alloys in memory applications. Recently, epitaxial Sb2Te3/GeTe superlattices were found to feature GexSb2Te3+x blocks as a result of intermixing between constituting layers. Here we present the epitaxy and characterization of Sb2Te3/GexSb2Te3+x van der Waals superlattices, where GexSb2Te3+x was intentionally fabricated. X-ray diffraction, Raman spectroscopy, scanning transmission electron microscopy, and lateral electrical transport data are reported. The intrinsic 2D nature of both sublayers is found to mitigate the intermixing in the structures, significantly improving the interface sharpness and ultimately the superlattice structural and electrical properties.

  10. Study on the local stress induced dislocations on (1 bar 1 bar 1 bar) Te face of CdTe-based crystals

    Science.gov (United States)

    Fu, Xu; Xu, Yadong; Xu, Lingyan; Gu, Yaxu; Jia, Ningbo; Jie, Wanqi

    2017-11-01

    The rosette-like dislocation clusters around Te inclusions in as-grown CdZnTe/CdTe crystals and those introduced by the micro-indentation on CdZnTe/CdTe surface are studied experimentally. The extended dislocation patterns are formed around Te inclusions in both CdZnTe and CdTe crystals, owing to the build-in stress. Two mutually orthogonal tetrahedrons are observed in CdZnTe crystal. However, the ;double-arms; dislocation rosette pattern extended along 〈1 1 0〉 direction is observed in CdTe crystal. The Peierls kink pair mechanism and the Hirsch effects are used to explain the discrepancy of these two different rosette patterns. Similar dislocation rosette patterns are observed on indentation surface of CdZnTe crystal. The dislocation rosette patterns are found to be independent of the indenter orientation, but completely determined by the crystallographic properties of zinc-blende structure of the crystal. Furthermore, the Te(g) and Cd(g) dislocation arms are found to be mixed and bended with each other in CdTe crystal under high indentation stress, making it different from that generated around Te inclusions. A model concerning the comprehensive impact of stress field and electronic polarities dislocations is proposed to clarify the dislocation bending phenomenon.

  11. Spin dynamics in bulk CdTe at room temperature

    International Nuclear Information System (INIS)

    Nahalkova, P.; Nemec, P.; Sprinzl, D.; Belas, E.; Horodysky, P.; Franc, J.; Hlidek, P.; Maly, P.

    2006-01-01

    In this paper, we report on the room temperature dynamics of spin-polarized carriers in undoped bulk CdTe. Platelets of CdTe with different concentration of preparation-induced dislocations were prepared by combining the mechanical polishing and chemical etching. Using the polarization-resolved pump-probe experiment in transmission geometry, we have observed a systematic decrease of both the signal polarization and the electron spin dephasing time (from 52 to 36 ps) with the increased concentration of defects. We have suggested that the Elliot-Yafet mechanism might be the dominant spin dephasing mechanism in platelets of CdTe at room temperature

  12. Thermodynamic assessment of the Ag-Te binary system

    Energy Technology Data Exchange (ETDEWEB)

    Gierlotka, Wojciech, E-mail: gilu@uci.agh.edu.p [Laboratory of Physical Chemistry and Electrochemistry, Faculty of Non-Ferrous Metals, AGH University of Science and Technology, 30 Mickiewicza Av., 30-059 Krakow (Poland)

    2009-10-19

    Pure silver and its alloys are very important materials for various technological applications. Tellurium is one of the unwanted admixture in silver and is removed during metallurgical processes; however Ag-Te alloy is necessary for production of rewritable digital versatile discs. The knowledge of phase diagram of Ag-Te is essential for applications and refining process. The critical assessment of binary system Ag-Te has been done using literature information. Good agreement between experimental data reported in literature and calculated values has been found.

  13. Infrared absorption in PbTe single crystals

    International Nuclear Information System (INIS)

    Kudykina, T.A.

    1982-01-01

    A group-theoretical analysis is conducted to select rules for optical transitions between bands in PbTe single crystals. It is shown that transitions between valence bands which are near a forbidden band are also forbidden. The extra absorption observed in p-PbTe and p-Pbsub(1-x)Snsub(x)Te in the region between the self-absorption edge and the free-carrier absorption edge is probably connected with transitions between one of valence bands and the p-state of the impurity

  14. TeV Diffuse Emission From the Inner Galaxy

    Directory of Open Access Journals (Sweden)

    Amid Nayerhoda

    2018-04-01

    Full Text Available The TeV diffuse emission from the Galactic plane is produced by multi TeV electrons and nuclei interacting with radiation fields and ambient gas, respectively. Measurements of the TeV diffuse emission help constrain CR origin and transport properties. We present a preliminary analysis of HAWC diffuse emission data from the inner Galaxy. The HAWC measurements will be used to constrain particle transport properties close to the Galaxy center correlating the HAWC maps with predictions of the DRAGON code.

  15. Preparation of Ta Te2 thin films by laser ablation

    International Nuclear Information System (INIS)

    Zidan, M.D.; Alkhwam, M.; Alkhasm, M.

    2006-03-01

    The laser ablation system consisting of a vacuum chamber and Nd-YAG laser has been built for deposition TaTe 2 on three different substrates (Silicon, glass, and Aluminium). The surface topography of the prepared thin films has been studied by atomic force microscopy (AFM). TaTe 2 powder was characterized by using x-ray diffraction. The crystallinity of the thin films was examined by x-ray diffraction (XRD). The results show no peaks corresponding TaTe 2 , but there are some indications to the Ta 3 N 5 . (author)

  16. Recent state of CdTe-based radiation detectors

    International Nuclear Information System (INIS)

    Ohno, R.

    2004-01-01

    Recent state for development of CdTe-based radiation detectors is reviewed. The progress of the technologies such as the crystal growth of CdTe and CdZnTe, the deposition of electrodes on the crystal, the design of read out ASIC, and the bonding between crystal and ASIC, opened the way for the development of imaging devices for practical uses. A X-ray imager for non destructive inspections and a gamma ray imager for small animal radioisotope experiments or nuclear medicine are presented as examples. (author)

  17. Delineation of phase fields at the Te-rich end of the Ru-Te binary system

    International Nuclear Information System (INIS)

    Ali, M.; Bharadwaj, S.R.; Das, D.

    2005-01-01

    The tellurium rich side of the ruthenium-tellurium binary system was studied by differential thermal analysis. To avoid reported problems of Te loss by evaporation and reactive interference of Te to the thermocouples of the thermal analyzer, the present study made use of specially designed sealed quartz capsules as DTA containers. The thermal analyses were carried out over the compositional range of 0.66 x Te 1.00 with the help of SETARAM TG/DTA and other indigenously built thermal analyzers available in this laboratory. The thermal data generated for fifteen different compositions were interpreted for the nature of phase transitions occurring at their characteristic temperatures. The Ru-Te binary system was found to have a eutectic transformation at 444 deg. C at a composition of x Te = 0.918 and a monotectic transformation at 447 deg. C at a composition of x Te = 0.700. Up to 6 at.% Ru is soluble in Te at about 440 deg. C

  18. Strong sp-d exchange coupling in ZnMnTe/ZnMgTe core/shell nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Wojnar, Piotr; Janik, Elzbieta; Szymura, Malgorzata; Zaleszczyk, Wojciech; Kret, Slawomir; Klopotowski, Lukasz; Wojciechowski, Tomasz; Baczewski, Lech T.; Wiater, Maciej; Karczewski, Grzegorz; Wojtowicz, Tomasz; Kossut, Jacek [Institute of Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Suffczynski, Jan; Papierska, Joanna [Institute of Experimental Physics, Warsaw University, ul. Hoza 69, 00-681 Warsaw (Poland)

    2014-07-15

    In this work, our recent progress in the growth and optical studies of telluride nanowire heterostructures containing a small molar fraction of magnetic Mn-ions of only a few percent is overviewed. ZnMnTe/ZnMgTe core/shell nanowires (NWs) are grown by molecular beam epitaxy by employing the vapor-liquid-solid growth mechanism assisted with gold catalyst. The structures are studied by means of photoluminescence and microphotoluminescence in an external magnetic field. In the first step, however, an activation of the near band edge emission from ZnTe and ZnMnTe nanowires is described, which is achieved by coating the nanowires with shells made of ZnMgTe. The role of these shells is to passivate Zn(Mn)Te surface states. The incorporation of Mn ions into the crystalline lattice of ZnMnTe nanowires is manifested as a considerable blue shift of near band edge emission with increasing Mn concentration inside the nanowire cores, which reflects directly the increase of their energy gap. In an external magnetic field the near band edge emission exhibits a giant spectral redshift accompanied by an increase of the circular polarization of the emitted light. Both effect are fingerprints of giant Zeeman splitting of the band edges due to sp-d exchange interaction between the band carriers and magnetic Mn-ions. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Optical properties of CuCdTeO thin films sputtered from CdTe-CuO composite targets

    Energy Technology Data Exchange (ETDEWEB)

    Mendoza-Galván, A., E-mail: amendoza@qro.cinvestav.mx [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico); Laboratory of Applied Optics, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden); Arreola-Jardón, G. [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico); Karlsson, L.H.; Persson, P.O.Å. [Thin Film Physics Division, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden); Jiménez-Sandoval, S. [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico)

    2014-11-28

    The effective complex dielectric function (ε) of Cu and O containing CdTe thin films is reported in the spectral range of 0.05 to 6 eV. The films were fabricated by rf sputtering from targets comprised by a mixture of CdTe and CuO powders with nominal Cu and O concentrations in the range of 2–10 at.%. Low concentration levels improved the crystalline quality of the films. Spectroscopic ellipsometry and transmittance measurements were used to determine ε. The critical point energies E{sub 1}, E{sub 1} + Δ{sub 1}, and E{sub 2} of CdTe are red-shifted with the incorporation of Cu and O. Also, an absorption band is developed in the infrared range which is associated with a mixture of CdTe and low resistivity phases Cu{sub 2−x}Te according to an effective medium analysis. The elemental distribution of the films was mapped by energy dispersive X-ray spectroscopy using scanning transmission electron microscopy. - Highlights: • Incorporation of 2 to 10 at.% of Cu and O atoms in CdTe films • Improved crystalline quality with 2 and 3 at.% of Cu and O • Complex dielectric function of Cu and O containing CdTe thin films • Effective medium modeling of below band-gap absorption.

  20. Numerical study of the influence of ZnTe thickness on CdS/ZnTe solar cell performance

    Science.gov (United States)

    Skhouni, Othmane; El Manouni, Ahmed; Mari, Bernabe; Ullah, Hanif

    2016-05-01

    At present most of II-VI semiconductor based solar cells use the CdTe material as an absorber film. The simulation of its performance is realized by means of various numerical modelling programs. We have modelled a solar cell based on zinc telluride (ZnTe) thin film as absorber in substitution to the CdTe material, which contains the cadmium element known by its toxicity. The performance of such photovoltaic device has been numerically simulated and the thickness of the absorber layer has been optimized to give the optimal conversion efficiency. A photovoltaic device consisting of a ZnTe layer as absorber, CdS as the buffer layer and ZnO as a window layer was modelled through Solar Cell Capacitance Simulator Software. Dark and illuminated I-V characteristics and the results for different output parameters of ZnO/CdS/ZnTe solar cell were analyzed. The effect of ZnTe absorber thickness on different main working parameters such as: open-circuit voltage Voc, short-circuit current density Jsc, fill factor FF, photovoltaic conversion efficiency η was intensely studied in order to optimize ZnTe film thickness. This study reveals that increasing the thickness of ZnTe absorber layer results in higher efficiency until a maximum value and then decreases slightly. This maximum was found to be 10% at ZnTe optimum thickness close to 2 µm. Contribution to the topical issue "Materials for Energy Harvesting, Conversion and Storage (ICOME 2015) - Elected submissions", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui