Carbon nanotubes have been subject to a great many theoretical and experimental investigations and have many interesting properties. However, the caps found at the ends of nanotubes have been rather neglected. Previous work has established the possible caps for a given nanotube. This thesis seeks to build on this work to determine which caps are probable. Three representative nanotubes are considered: the (5,5) tube (an example of a metal); the (10,0) tube (an example of an insulator) and the (11,2) tube (for which experimental data is available). A linear scaling density matrix method based on orthogonal tight-binding theory is used for a systematic study of doubly capped nanotubes. The energetically most stable caps are found for all three tubes and the isolated pentagon rule established for fullerenes is shown to be valid for nanotube caps. No simple rule governing the stability of isolated pentagon caps is found, although the stability of (11,2) caps correlates well with the number of hexagons adjacent to just one pentagon. The local densities of states (LDOS) are calculated for the most stable cap for each nanotube. A localised state is found for the capped (5,5) tube and a resonant state is observed for the capped (11,2) tube. The LDOS for the capped (11,2) tube is compared with experimental observations and questions are raised concerning the nature of the tube observed and the limitations of STM as a method for identifying nanotube caps.

The Army-sponsored Institute for Soldier Nanotechnologies (ISN) was an entrepreneurial research institute established at the Massachusetts Institute of Technology (MIT) in 2002. Using Science and Technology Studies (STS) concepts from Actor-Network Theory, I study the founding era of this twenty-first century laboratory-based community, from 2002-2007. Actor-Network concepts of enrollment and translation, described by Bruno Latour, and heterogeneous engineering, described by John Law, are used as I 'follow the actors' founding this emergent institution. The operationalization of translation is traced through four case studies, structured around Defense funding constructs and Science and Technology communities: 6.0 Founding the Institute; 6.1 Building Basic Research Networks; 6.2 Shaping Applied Research for Cancer Research and Science Education to include non-users; and 6.3 Student Prototyping Teams Accelerating ISN Research for Traumatic Brain Injuries (TBI). Scientists, engineers, and transitioners partnered in new ways to transition innovative technologies to improve human protection, with soldiers as the first of many users. Using public information, I used qualitative and quantitative methodologies to assess the actor networks and research portfolio changes. These historical case studies extend STS with operationalization of translation and a new dynamic of bi-directional actor enrollment, as research teams transitioned nanotechnologies and prototypes. / Doctor of Philosophy / The Institute for Soldier Nanotechnologies (ISN) was an Army-sponsored entrepreneurial research institute established at the Massachusetts Institute of Technology (MIT) in 2002. This historical study examines the founding era, rarely described for start-up organizations. Science and Technology Studies (STS) concepts of Actor-Network Theory enrollment and translation are traced through four case studies: Founding the Institute; Building Basic Research Networks; Shaping Applied Research for Cancer Research and Science Education to include non-users; and Student Prototyping Teams Accelerating Research for Traumatic Brain Injuries (TBI). The scientists, engineers, and transitioners partnered in new ways to transition technologies to improve human protection, with soldiers as the first of many users. Using public information, I provide qualitative and quantitative methodologies to assess the social networks of actors, as well as the composition and changes in the research portfolio. These case studies show what the ISN members did and how the small teams innovated, operationalizing translation through enrollment, and transitioning nanotechnologies and other prototypes.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-26T17:10:11Z No. of bitstreams: 1 2011 - Jorge Luiz dos Santos Junior.pdf: 2785492 bytes, checksum: 990333e796ea65f8c9af8566767bca47 (MD5) / Made available in DSpace on 2016-07-26T17:10:11Z (GMT). No. of bitstreams: 1 2011 - Jorge Luiz dos Santos Junior.pdf: 2785492 bytes, checksum: 990333e796ea65f8c9af8566767bca47 (MD5) Previous issue date: 2011-12-02 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / SANTOS JUNIOR, Jorge Luiz dos. Science of the future: the research community and the nanoscience policy cycle in Brazil. 2011. 215 p. Thesis (Social Science Doctorate in Development, Agriculture and Society). Human and Social Sciences Institute, Federal Rural University of Rio de Janeiro, RJ. 2011. Insofar as nanoscience and nanotechnology (N&N) permit the manipulation of individual atoms to create new (organic and inorganic) materials and combinations they can be viewed as Man?s latest incursion in the sphere of his efforts to dominate, transform and recreate nature. They arouse various kinds of interest and stir up controversies typical of a risk society, provoking critical views of the future of humanity and bringing with them a set of uncertainties and disputes that are consubstantiated in the institutionalization of this sector. This thesis analyses the participation of the scientific community in the nanoscience and nanotechnology policy cycle in Brazil by identifying and interpreting the inter-relations of the various actors that make up the complex network associated to this study area. To that end an analysis is made of the government programs, the configuration of the research groups, the performance of the social movements and the role of corporations, using as a reference framework Agency Theory, Social Studies in Science Technology and Society and in Relational Sociology. The Structural Analysis of Social Networks also serves as an important working method. The research concludes that a scientific community exists largely composed of actors from the fields of physics and chemistry, with special rights of entry in the entire policy cycle thereby revealing the State?s effective permeability in questions of science and technology policies. The fact has led to a considerable weakness of policy in regard to studies of ethical impacts, environmental risks or the participation of other fields of research in the discussions on the directions of science and technology in Brazil. / SANTOS JUNIOR, Jorge Luiz dos. Ci?ncia do futuro: a comunidade de pesquisa e o ciclo da pol?tica de nanoci?ncia no Brasil. 2011. 215 p. Tese (Doutorado de Ci?ncias Sociais em desenvolvimento, Agricultura e Sociedade). Instituto de Ci?ncias Humanas e Sociais, Universidade Federal Rural do Rio de Janeiro, RJ. 2011. A nanoci?ncia e a nanotecnologia (N&N), ao permitirem a manipula??o de ?tomos individualizados para criar novos elementos e mat?rias (org?nicos e inorg?nicos), podem ser compreendidas como a mais recente incurs?o do homem na tentativa de dominar, transformar e recriar a natureza. Despertam interesses diversos e acirram controv?rsias, caracter?sticas de uma sociedade de risco, provocando olhares cr?ticos acerca do futuro da humanidade, trazendo consigo um conjunto de incertezas e disputas que se consubstanciam na institucionaliza??o desse setor. Nessa tese analisamos a participa??o da comunidade cient?fica no ciclo da pol?tica de nanotecnologia e nanoci?ncia (N&N) no Brasil, atrav?s da identifica??o e interpreta??o das inter-rela??es entre os diversos atores que comp?em uma complexa rede nesse campo de estudo. Para tanto, foram analisados os programas governamentais, a configura??o dos grupos de pesquisa, a atua??o dos movimentos sociais e o papel das empresas, tendo como marco de refer?ncia a Teoria da Ag?ncia, os Estudos Sociais em Ci?ncia, Tecnologia e Sociedade e a Sociologia Relacional. Traz tamb?m a An?lise Estrutural de Redes Sociais como importante m?todo de trabalho. Ao final do trabalho, conclu?mos que existe uma comunidade de pesquisa, composta majoritariamente por atores das ?reas de f?sica e qu?mica que t?m entrada especial em todo o ciclo da pol?tica, caracterizando a permeabilidade do Estado no que toca ?s pol?ticas de ci?ncia e tecnologia. Tal fato contribui para a fragiliza??o da pol?tica no que concerne aos estudos sobre impactos ?ticos, riscos ambientais e ? participa??o de outros campos de pesquisa nas discuss?es sobre os rumos da ci?ncia e da tecnologia no Brasil