Separation of Ba-137m from Cs-137 using new ion exchanger Na-2(H2O)(4)(H3O)[Al(OH)(6)Mo6O18]

A new polyoxometalate of chemical formula, Na-2(H2O)(4)(H3O)[Al(OH)(6)Mo6O18] (1) containing Anderson type large anion has been synthesized and characterized by single-crystal X-ray structure determination and IR spectroscopic studies. The crystal of 1 is triclinic, spacegroup P-1 with cell dimensions, a = 6.365(9) angstrom, b = 10.37(1) angstrom, c = 10.44(1) angstrom and alpha = 65.41(1), beta = 77.18(1), gamma = 86.58(1) and Z = 1. The compound 1 behaves as an ion exchanger and is stable in thermal, radiation and chemical environments. Radiochemical separation of the short-lived daughter Ba-137m (t(1/2) = 2.50 min) from its long-lived parent Cs-137 using this newly designed and synthesized ion exchanger has been developed.

Adapting brief Behavioural Activation (BA) for adolescent depression: a case example

There is an increasing evidence base for the effectiveness of Behavioural Activation in treating adult depression; however, there has been little investigation of using this approach with adolescents. This article reports on the adaptation of brief Behavioural Activation for Depression (BATD) for adolescents (BATD-A). A case study is reported to illustrate the brief structured approach, treatment response as indicated by routine outcome measures, and the family’s view of the intervention. The adaptations made to the adult BATD manual are discussed including parental input, adapted values and activities, and engagement issues. It is hoped that following further evaluation, BATD-A could be successfully delivered as a low-intensity intervention for depression.

Optical and dielectric relaxor behaviour of Ba(Zr(0.25)Ti(0.75))O(3) ceramic explained by means of distorted clusters

In this work, Ba(Zr(0.25)Ti(0.75))O(3) ceramic was prepared by solid-state reaction. This material was characterized by x-ray diffraction and Fourier transform Raman spectroscopy. The temperature dependent dielectric properties were investigated in the frequency range from 1 kHz to 1 MHz. The dielectric measurements indicated a diffuse phase transition. The broadening of the dielectric permittivity in the frequency range as well as its shifting at higher temperatures indicated a relaxor-like behaviour for this material. The diffusivity and the relaxation strength were estimated using the modified Curie-Weiss law. The optical properties were analysed by ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements at room temperature. The UV-vis spectrum indicated that the Ba(Zr(0.25)Ti(0.75))O(3) ceramic has an optical band gap of 2.98 eV. A blue PL emission was observed for this compound when excited with 350 nm wavelength. The polarity as well as the PL property of this material was attributed to the presence of polar [TiO(6)] distorted clusters into a globally cubic matrix.

Phase-transition studies of Ba(0.90)Ca(0.10)(Ti(1-x)Zr(x))O(3) ferroelectric ceramic compounds

Perovskite-structured Ba(0.90)Ca(0.10)(Ti(1-x)Zr(x))O(3) ceramics were prepared in this work and subsequently studied in terms of composition-dependent dielectric and high-resolution long-range order structural properties from 30 to 450 K. The dielectric response of these materials was measured at several frequencies in the range from 1 kHz to 1 MHz. Combining both techniques, including Rietveld refinement of the X-ray diffraction data, allowed observing that, when increasing Zr(4+) content, the materials change from conventional to diffuse and relaxor ferroelectric compounds, the transition occurring spontaneously at the x = 0.18 composition. Interestingly, this spontaneous transition turned out to be prevented for a further increase of Zr(4+). On the basis of all the dielectric and structural results processed, a phase diagram of this system is presented. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Structure and optical properties of [Ba(1-x)Y(2x/3)](Zr(0.25)Ti(0.75))O(3) powders

[Ba(1-x)Y(2x/3)](Zr(0.25)Ti(0.75))O(3) powders with different yttrium concentrations (x = 0, 0.025 and 0.05) were prepared by solid state reaction. These powders were analyzed by X-ray diffraction (XRD). Fourier transform Raman scattering (FT-RS), Fourier transform infrared (FT-IR) and X-ray absorption near-edge (XANES) spectroscopies. The optical properties were investigated by means of ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements. Even with the addition of yttrium, the XRD patterns revealed that all powders crystallize in a perovskite-type cubic structure. FT-RS and FT-IR spectra indicated that the presence of [YO(6)] clusters is able to change the interaction forces between the O-Ti-O and O-Zr-O bonds. XANES spectra were used to obtain information on the off-center Ti displacements or distortion effects on the [TiO(6)] clusters. The different optical band gap values estimated from UV-vis spectra suggested the existence of intermediary energy levels (shallow or deep holes) within the band gap. The PL measurements carried out with a 350 nm wavelength at room temperature showed that all powders present typical broad band emissions in the blue region. (C) 2010 Elsevier Masson SAS. All rights reserved.

Tectonic fabric revealed by AARM of the proterozoic mafic dike swarm in the Salvador city (Bahia state): Sao Francisco Craton, NE Brazil

Magnetic fabric and rock magnetism studies were performed on 25 unmetamorphosed mafic dikes of the Meso-Late Proterozoic (similar to 1.02 Ga) dike swarm from Salvador (Bahia State, NE Brazil). This area lies in the north-eastern part of the Sao Francisco Craton, which was dominantly formed/reworked during the Transamazonian orogeny (2.14-1.94 Ga). The dikes crop out along the beaches and in quarries around Salvador city, and cut across both amphibolite dikes and granulites. Their widths range from a few centimeters up to 30 m with an average of similar to 4 m, and show two main trends N 140-190 and N 100-120 with vertical dips. Magnetic fabrics were determined using both anisotropy of low-field magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent magnetization (AARM). The magnetic mineralogy was investigated by many experiments including remanent magnetization measurements at variable low temperatures (10-300 K), Mossbauer spectroscopy, high temperature magnetization curves (25-700 degrees C) and scanning electron microscopy (SEM). The rock magnetism study suggests pseudo-single-domain magnetite grains carrying the bulk magnetic susceptibility and AARM fabrics. The magnetite grains found in these dikes are large and we discard the presence of single-domain grains. Its composition is close to stoichiometric with low Ti substitution, and its Verwey transition occurs around 120 K. The main AMS fabric recognized in the swarm is so-called normal, in which the K(max)-K(int) plane is parallel to the dike plane and the magnetic foliation pole K(min)) is perpendicular to it. This fabric is interpreted as due to magma flow, and analysis of the K m inclination permitted to infer that approximately 80% of the dikes were fed by horizontal or sub-horizontal flows (K(max) < 30 degrees). This interpretation is supported by structural field evidence found in five dikes. In addition, based on the plunge of K(max), two mantle sources could be inferred; one of them which fed about 80% of the swarm would be located in the southern part of the region, and the other underlied the Valeria quarry. However, for all dikes the AARM tensors are not coaxial with AMS fabrics and show a magnetic lineation (AARM(max)) oriented to N30-60E, suggesting that magnetite grains were rotated clockwise from dike plane. The orientation of AARM lineation is similar to the orientation of a system of faults in which the Salvador normal fault is the most important. These faults were formed during Cretaceous rifting in the Reconcavo-Tucano-jatoba assemblage that corresponds to an aborted intra-continental rift formed during the opening of the South Atlantic. Therefore, the AARM fabric found for the Salvador dikes is probably tectonic in origin and suggests that the dike swarm was affected by the important tectonic event responsible for the break-up of the Gondwanaland. (C) 2008 Elsevier B.V. All rights reserved.

Zr- AND Ba-RICH MINERALS FROM THE PONTE NOVA ALKALINE MAFIC-ULTRAMAFIC MASSIF, SOUTHEASTERN BRAZIL: INDICATION OF AN ENRICHED MANTLE SOURCE

Zirconium- and Ba-rich minerals are found in gabbroic rocks from the Ponte Nova alkaline mafic-ultramafic massif in southeastern Brazil. The unusual mineralogical assemblage includes zirconolite, baddeleyite, Ba-rich alkali feldspar, and Ba- and Ti-rich biotite. Zirconolite of the Ponte Nova massif has higher levels of Zr (up to 1.172 apfu) than those registered in other terrestrial rocks and a prominent enrichment in the light rare-earth elements. Baddeleyite contains small quantities of Hf, Ti, and Fe. The Ba-rich alkali feldspar and Ba- and Ti-rich biotite contain up to 9.25 and 7.35 wt% BaO, respectively, and the biotite contains up to 12.01 wt% TiO(2). In the different intrusions of the Ponte Nova massif, such an unusual assemblage typifies the residual magma after the crystallization of clinopyroxene and olivine from previously enriched basanitic parental magma. The different trends of enrichments in REE and Th + U found for zirconolite of the intrusions of the Ponte Nova massif provide a better understanding of the variable degrees of enrichment of incompatible elements of the distinct gabbroic bodies. A lithospheric mantle source enriched in incompatible elements by the metasomatic action of volatile-rich fluids and with the presence of phlogopite or amphibole (or both) and other minor accessory phases could explain the presence of the Zr- and Ba-rich minerals in this gabbroic massif.

Leakage current, ferroelectric and structural properties in Pb(1-x)Ba(x)TiO(3) thin films prepared by chemical route

Single-phase perovskite structure Pb(1-x)Ba(x)TiO(3) thin films (x = 0.30, 0.50 and 0.70) were deposited on Pt/Ti/SiO(2)/Si substrates by the spin-coating technique. The dielectric study reveals that the thin films undergo a diffuse type ferroelectric phase transition, which shows a broad peak. An increase of the diffusivity degree with the increasing Barium contents was observed, and it was associated to a grain decrease in the studied composition range. The temperature dependence of the phonon frequencies was used to characterize the phase transition temperatures. Raman modes persist above tetragonal to cubic phase transition temperature, although all optical modes should be Raman inactive. The origin of these modes was interpreted in terms of breakdown of the local cubic symmetry by chemical disorder. The absence of a well-defined transition temperature and the presence of broad bands in some interval temperature above FE-PE phase transition temperature Suggested a diffuse type phase transition. This result corroborates the dielectric constant versus temperature data, which showed a broad ferroelectric phase transition in these thin films. The leakage Current density of the PBT thin films was studied at different temperatures and the data follow the Schottky emission model. Through this analysis the Schottky barrier height values 0.75, 0.53 and 0.34 eV were obtained to the PBT70, PBT50 and PBT30 thin films, respectively. (C) 2008 Elsevier Ltd. All rights reserved.

Uma Comparação Fenomenográfica das Pesquisas Científicas sobre o Ensino de Sociologia na Rede Escolar Sueca e Pública Brasileira

O objetivo deste artigo é realizar um estudo sobre as perspectivas teórica-metodológicas sobre o ensino de licenciatura em Ciências Sociais, no Brasil e na Suécia. Priorizando uma análise dos temas, das teórias e das conclusões das teses escritas em inglês, sueco e em português sobre a temática, quero aprensentar uma revisão bibliográfica sobre o tema, produzida no período entre 2006-2012

The Family Novel in the Emerging Nation-State: A Comparative Study of Ba Jin’s Jia and Lev Tolstoy’s Anna Karenina

The theme of family in literature and in popular discourse occurs at times when the family as an institution is under attack. Attacks against the family coupled with defence of the family are viewed as the barometer of people’s satisfaction with the society in which they live. This outpouring of emotion, whether it is in defence of or attacking the family, is the result of the family’s position on the bridge between nature and society – a fortunate (or a detrimental) link between an individual and the units that make up a society. Across the United States and much of the western world, the battle for gay marriage and inclusive civil unions has revealed the fissures in our collective moral view of the family. The conservative concern about the absence of ‘family values’ is magnified by our situation in a world of flux. Inflation, war, terrorist threats, and the depletion of natural resources are but a few examples. When so much is unknown, how do we position ourselves? What anchors us to the past, gives us comfort in the present, and supports us in the future if not the family? Alternatively, what coddles us more in the past, shackles us more to the present, and lulls us more into a fixed conception of the future than the family? My research is not a sociological survey into the family nor does it stake any claims to understanding the present state of the family in society. The study seeks, however, to shed light on the rhetorical uses of the family by analysing two novels that are inextricably concerned with the theory of the family in times of heightened social change. In particular, my research focuses upon the social role and political meaning of the family in Anna Karenina and Jia.

Too Many Bad Cooks Spoiling the Broth? Effectiveness of NGOs in Addressing Child Labour in El Salvador

The reaction of the first world to the persevering plight of a large part of the third world varies. In response to the sometimes glaring disparities, many international organizations and multinational corporations have recently adopted a pro-development rhetoric with relation to the problem of global poverty. However, the rhetoric rarely translates into action. As David Bacon discusses, leaders of corporations and organizations now tend to conclude their speeches by expressing a desire to reduce the suffering of the third world. However, when it comes to agreeing on specific concessions that could indeed improve the world-wide economic situation, first world countries are reluctant to act. A good example of this type of behavior is the current negotiation of the WTO, the “development round of Doha,” in which the United States along with the European Union pressure countries of the developing South to open up their markets, while at the same time refusing to remove or even decrease their own agricultural subsidies. The first world civil society observes the behavior of international organizations and western based multinational corporations as ineffectual. Taking the matter in its own hands, especially in the past couple of decades, this civil society has created a countless number of development-oriented nongovernmental organizations. These are supposed to compensate for the lack of action by international organizations. Development NGOs are believed to be more locally responsive as well as free of business or political considerations in choosing their strategies, and thus generally more efficient than IOs. However, if they really were how they are alleged to be, the problems of the third world would already be ameliorated by a significant amount, if not completely eradicated. Do development-NGOs indeed possess the characteristics that they claim to possess? What is their real affect on human rights? And how effective are they in their work?

Influencia de variaveis ambientais sobre a temperatura do ar na area urbana de Porto Alegre, RS

Com o objetivo de verificar qual o controle mais importante das temperaturas no meio urbano, correlacionou-se a temperatura observada em seis estações meteorológicas com três índices representativos do ambiente em torno de cada abrigo meteorológico. Os dados de temperatura corresponderam às médias das temperaturas mínimas e às médias das temperaturas máximas do período abril 1985-março 1986. Também foram extraídos deste conjunto de dados, amostras sazonais de 2 dias consecutivos com tempo anticiclônico. O ambiente em torno dos abrigos meteorológicos foi caracterizado por três variáveis: ângulo de obstrução do horizonte (obstrução por edificações, por vegetação e máxima obstrução), cobertura, vegetal em 10.000 m2 e 40.000 m2 e superfície com edificações também em 10.000 m2 e 40.000 m2. A correlação da obstrução do horizonte por edificações com a média das temperaturas mínimas foi a mais significativa. Diferenças observadas entre a situação outono-inverno e primavera-verão, entretanto, sugerem controle significativo da circulação atmosférica regional.