Stellar black holes at the dawn of the universe

It is well established that between 380000 and 1 billion years after the Big Bang the Inter Galactic Medium (IGM) underwent a "phase transformation" from cold and fully neutral to warm (~10^4 K) and ionized. Whether this phase transformation was fully driven and completed by photoionization by young hot stars is a question of topical interest in cosmology. AIMS. We propose here that besides the ultraviolet radiation from massive stars, feedback from accreting black holes in high-mass X-ray binaries (BH-HMXBs) was an additional, important source of heating and reionization of the IGM in regions of low gas density at large distances from star-forming galaxies. METHODS. We use current theoretical models on the formation and evolution of primitive massive stars of low metallicity, and the observations of compact stellar remnants in the near and distant universe, to infer that a significant fraction of the first generations of massive stars end up as BH-HMXBs. The total number of energetic ionizing photons from an accreting stellar black hole in an HMXB is comparable to the total number of ionizing photons of its progenitor star. However, the X-ray photons emitted by the accreting black hole are capable of producing several secondary ionizations and the ionizing power of the resulting black hole could be greater than that of its progenitor. Feedback by the large populations of BH-HMXBs heats the IGM to temperatures of ~10^4 K and maintains it ionized on large distance scales. BH-HMXBs determine the early thermal history of the universe and mantain it as ionized over large volumes of space in regions of low density. This has a direct impact on the properties of the faintest galaxies at high redshifts, the smallest dwarf galaxies in the local universe, and on the existing and future surveys at radio wavelengths of atomic hydrogen in the early universe.Comment: 7 pages, 2 figures, accepted to be published in Astronomy and Astrophysic

Ceramic foam supported active materials for boron remediation in water

Due to the narrowrange between boron necessities and toxicity in the environment, there is a high interest in the design of effective boron remediation procedures. We have previously reported a promising boron adsorptionmaterial based on the affinity of boron aqueous species for cis-diol groups that were anchored on differentmesoporous silica matrices.However, the small particle size of these systemsmakes themdifficult to be applied on real remediation situations. In this context we report herein a novel systemfor boron adsorption fromaqueous solutions inwhich the high boron affinity for functionalized mesoporousmaterials is combined with themechanical properties of ceramic foams as macroscopic supports. The efficiency of these new composites for boron removal is very high and comparable with the parent microparticulated adsorbent.Financial support from the Spanish Government (Project MAT2009-14564-C04-01 and MAT2009-14564-C04-04, and MAT2012-38429-C04-01 and MAT2012-38429-C04-02) and the Generalitat Valenciana (Project PROMETEO/2009/016) is gratefully acknowledged. C.S. thanks the MICINN for a predoctoral fellowship.Sanfeliu Cano, C.; Martínez-Máñez, R.; Sancenón Galarza, F.; Soto Camino, J.; Amoros Del Toro, PJ.; Marcos Martínez, MD. (2015). Ceramic foam supported active materials for boron remediation in water. Desalination. 374:10-19. https://doi.org/10.1016/j.desal.2015.06.020S101937

A defesa das relações de consumo : teorias, experiências e o papel do Ministério Público Federal

No mundo todo, a importância da defesa das relações de consumo vem obtendo crescimento deveras significativo ao longo dos tempos, juntamente com a evolução das sociedades. No Brasil, vários motivos podem ser apontados para explicar tal fato, sendo que dentre os principais destacam-se os mais recentes, quais sejam: as mudanças nas relações de comércio, com a conscientização de consumidores e fornecedores de bens e serviços acerca de seus direitos e obrigações; a modernização e o aparelhamento dos órgãos estatais com atuação específica na defesa do consumidor (PROCONs, Ministério Público Federal e Estadual, Conselho Nacional de Defesa do Consumidor do Ministério da Justiça); o surgimento de várias instituições não governamentais (ONGs) de defesa do consumidor, criados pela sociedade civil organizada; a entrada em vigor de legislação específica, o Código de Defesa do Consumidor através da lei nº 8.078/90. Uma instituição como o Ministério Público, defensor da sociedade por definição, e mormente após a promulgação da Constituição Federal de 1988, teve ampliada sobremaneira sua incumbência e responsabilidade na defesa dos interesses da população consumidora em suas relações. Desse modo, a presente dissertação propõe-se a descrever e analisar as relações de consumo, tanto no Brasil quanto em outros centros capitalistas desenvolvidos, como os Estados Unidos da América e países da União Europeia. Será relatada e analisada, ainda, a maneira como o Ministério Público Federal executa sua missão constitucional, com a apresentação de alguns casos reais, concretos, que versam sobre a atuação do órgão ministerial na defesa dos consumidores, das comunidades e da ordem econômica.All over the world, the importance of the defense in the consumption relations has gained a very signficant growth over time, along with the evolutions of societies. In Brazil, several reasons can be pointed to explain this fact, and among the main stand out the most recent, namely: the changes in trade relations, with the awareness of consumers and providers of goods and services about their rights and obligations; modernization and equipment of state agencies with specific actions in consumer protection (PROCONs, Federal Public Prosecution Service, the National Council of Consumer Affairs Ministry of Justice); the emergence of several non-governmental institutions (NGOs) in consumer defense, raised by civil society organization; the entry into force of specific legislation, the Consumer Protection Code by Law No. 8.078/90. An institution as the Public Prosecution Service, defender of society by definition, and especially after the promulgation of the Constitution of 1988, had greatly extended its mandate and responsibility in defending the interests of consumers in their relations. Thus, this paper proposes to describe and analyze the relations of consumption, both in Brazil and in other developed capitalist centers, such as the United States of America and European Union countries. It will be reported and analyzed, furthermore, how the Federal Public Prosecution Service performs its constitutional mission, with the presentation of some real cases, specific, which focus on the performance of ministerial body in protecting consumers, communities and economic order

A defesa das relações de consumo : teorias, experiências e o papel do Ministério Público Federal

No mundo todo, a importância da defesa das relações de consumo vem obtendo crescimento deveras significativo ao longo dos tempos, juntamente com a evolução das sociedades. No Brasil, vários motivos podem ser apontados para explicar tal fato, sendo que dentre os principais destacam-se os mais recentes, quais sejam: as mudanças nas relações de comércio, com a conscientização de consumidores e fornecedores de bens e serviços acerca de seus direitos e obrigações; a modernização e o aparelhamento dos órgãos estatais com atuação específica na defesa do consumidor (PROCONs, Ministério Público Federal e Estadual, Conselho Nacional de Defesa do Consumidor do Ministério da Justiça); o surgimento de várias instituições não governamentais (ONGs) de defesa do consumidor, criados pela sociedade civil organizada; a entrada em vigor de legislação específica, o Código de Defesa do Consumidor através da lei nº 8.078/90. Uma instituição como o Ministério Público, defensor da sociedade por definição, e mormente após a promulgação da Constituição Federal de 1988, teve ampliada sobremaneira sua incumbência e responsabilidade na defesa dos interesses da população consumidora em suas relações. Desse modo, a presente dissertação propõe-se a descrever e analisar as relações de consumo, tanto no Brasil quanto em outros centros capitalistas desenvolvidos, como os Estados Unidos da América e países da União Europeia. Será relatada e analisada, ainda, a maneira como o Ministério Público Federal executa sua missão constitucional, com a apresentação de alguns casos reais, concretos, que versam sobre a atuação do órgão ministerial na defesa dos consumidores, das comunidades e da ordem econômica.All over the world, the importance of the defense in the consumption relations has gained a very signficant growth over time, along with the evolutions of societies. In Brazil, several reasons can be pointed to explain this fact, and among the main stand out the most recent, namely: the changes in trade relations, with the awareness of consumers and providers of goods and services about their rights and obligations; modernization and equipment of state agencies with specific actions in consumer protection (PROCONs, Federal Public Prosecution Service, the National Council of Consumer Affairs Ministry of Justice); the emergence of several non-governmental institutions (NGOs) in consumer defense, raised by civil society organization; the entry into force of specific legislation, the Consumer Protection Code by Law No. 8.078/90. An institution as the Public Prosecution Service, defender of society by definition, and especially after the promulgation of the Constitution of 1988, had greatly extended its mandate and responsibility in defending the interests of consumers in their relations. Thus, this paper proposes to describe and analyze the relations of consumption, both in Brazil and in other developed capitalist centers, such as the United States of America and European Union countries. It will be reported and analyzed, furthermore, how the Federal Public Prosecution Service performs its constitutional mission, with the presentation of some real cases, specific, which focus on the performance of ministerial body in protecting consumers, communities and economic order

Sur le points critiques des fontions analytiques reelles

Consiglio Nazionale delle Ricerche (CNR). Biblioteca Centrale / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

Hierarchically‐Ordered Zeolites: A Critical Assessment

Abstract Hierarchically‐ordered zeolites have received increasing attention in the last 15 years due to their outstanding properties, which are explored in catalytic reaction with industrial relevance. Up to now, a large number of different synthetic strategies have been reported that allow to introduce an additional meso‐ or macropore system in addition to the intrinsic microporosity of classical zeolites. Thus, hierarchical zeolites combine the intrinsic (catalytic) properties of conventional zeolites with facilitated access and transport via the additional pore system. In this critical review, the various synthesis pathways reported so far are evaluated, several physico‐chemical methods required for in‐depth characterization of the hierarchical pore system are discussed, and selective applications that are or potentially will be of technical relevance are introduced. The present review provides a critical analysis of the present achievements and discusses future opportunities and challenges for the research on hierarchically‐ordered zeolite in particular with respect to their industrial use