Federal University of Roraima

About: Federal University of Roraima is a based out in . It is known for research contribution in the topics: Population & Thermogravimetry. The organization has 981 authors who have published 1218 publications receiving 7849 citations. The organization is also known as: Federal University of Roraima.

Estimating the value of the metal-ligand bond dissociation enthalpy (M-L) for adducts using empirical equations supported by TG data

Abstract: In this work is presented and tested (for 106 adducts, mainly of the zinc group halides) two empirical equations supported in TG data to estimate the value of the metal-ligand bond dissociation enthalpy for adducts: (M-O) = ti / g if ti (M-O) = (ti / g ) - 7,75 10-2 ti if ti > 420 K In this empirical equations, ti is the thermodynamic temperature of the beginning of the thermal decomposition of the adduct, as determined by thermogravimetry, andg is a constant factor that is function of the metal halide considered and of the number of ligands, but is not dependant of the ligand itself To half of the tested adducts the difference between experimental and calculated values was less than 5% To about 80% of the tested adducts, the difference between the experimental (calorimetric) and the calculated (using the proposed equations) values are less than 15%

GENTRIFICAÇÃO E POLÍTICAS DE REVITALIZAÇÃO NOS CENTROS HISTÓRICOS NO BRASIL: processos que levam ao déficit habitacional

Abstract: O presente artigo consiste numa discussao critica sobre as politicas de preservacao dos centros historicos brasileiros que defendem a permanencia e a defesa dos grupos e culturas locais, mas que, na pratica, assemelhamse ao processo de gentrificacao que acirra problemas de moradia por inserir nesses espacos o consumismo da cultura. O processo de gentrificacao associado aos interesses empresariais inevitavelmente expulsa os moradores dessas areas consideradas patrimonio para a criacao de paisagens de poder, em detrimento do vernacular, para fins de exploracao comercial. Isso cria novas centralidades que proporcionam maiores retornos aos investimentos financeiros realizados.

Rearing and trade of wild birds in a semiarid region of Brazil

Abstract: The rearing of wild birds as pets is directly related to cultural and socioeconomic issues, as well as to population declines for the species involved. This study aimed to inventory wild birds that are reared as pets and analyze aspects of their commercialization and the sociocultural context of this activity in the semiarid region of Paraiba, Brazil. The data were obtained through interviews and semistructured questionnaires comprised of questions regarding wild birds kept in captivity. Thirty men with a mean age of 45 years were interviewed. The birds were identified through direct observation of the species. The Use Value Index, which is a quantitative index that lists species by importance based on usage citations, was calculated for each species in three different ways: UVgeneral, UVcurrent, and UVpotential. Thirty-six wild bird species distributed among 10 families and 26 genera were recorded. The birds were raised because of beautiful plumage and birdsong, ability to mimic sounds, and fighting potential. Trade on wild birds is a widespread activity. Twenty-one (70%) interviewees had obtained their animals from illegal trade, which encompassed all recorded species. Nine respondents were authorized to legally raise and breed these species in captivity. Bird trade is a widespread activity throughout the study region, where individuals of many species are sold at prices ranging from R$ 5.00 (US$ 1.29) to R$ 5000.00 (US$ 1288.85). The results demonstrate the need to implement effective public policies aim at mediating the use and conservation of avian biodiversity, and improving the implementation of management plans for its conservation.

O Garimpo Ilícito na Terra Indígena Yanomami entre a Cosmovisão Indígena e Ações Estatais

Abstract: Gold mining in the Amazon, especially in mines in the interior of indigenous lands, is a proftable, polluting and illegal activity, classifed as criminal by state legislation. It is carried out clandestinely with the use of personnel and equipment that suck up material from the riverbed or through the blasting of gullies, with further separation of the gold through gravimetry and amalgamation processes, with the use and disposal of mercury into the environment. The objective of this study is to compare the consequences of mining among Amerindian perceptions, especially of the Yanomami Indians, under the anthropological categories of perspectivism and multinaturalism and the state criminal justice system, arising from the environmental crime protection. This bibliographic and documentary analysis, comprises the juridical and anthropological literature and testimonies of those involved in the mining of the Yanomami Indigenous Land, as well as the participant observation of the authors, who research and act in professional activities related to the phenomenon, analyzing the state responses to a particular case of illegal gold extraction in the Yanomami Indigenous Land, which took place in July 2017. It was found that, under Amerindian perspectivism, there is a distinct view of the man-nature relationship. From this view, discourse and actions of greater respect and value to the environment are presented; these being more antagonistic than that of the state justice system in relation to the consequences of mining in the Amazon. In the Yanomami discourse, the smoke produced during the mining activities –also known as Xawara - will culminate in incurable diseases and the fall of the sky, or in the equivalent non-indigenous western understanding, the end of the world. In the state criminal justice system, soft legal consequences apply to those involved in the illegal extraction of gold; it is considered a lower offence crime and as a rule, imprisonment is not stipulated for those involved, generating a sense of impunity and reiteration of illegal practices that generate pollution.

Organic fertilization for the beginning of sweet potato (Ipomoea batatas L.) cultivation in savanna soils

Abstract: Debido a la limitada informacion sobre el cultivo de camote (Ipomoea batatas L.) en areas silvestres de la sabana, el objetivo de este estudio fue determinar la dosis ideal y el tipo de fertilizante organico para el cultivo de camote en suelos de la sabana sin antecedentes de explotacion. Se probaron diferentes dosis de fertilizantes en cuatro experimentos: estiercol de ganado (0, 10, 20, 30 y 40 t·ha-1), pollinaza (0, 5, 10, 15 y 20 t·ha-1), compost A (0, 0.75, 1.5, 2.25 y 3.0 t·ha-1) y compost B (0, 0.75, 1.5, 2.25 y 3.0 t·ha-1). El quinto experimento consistio en una prueba de eficiencia de fertilizantes organicos utilizando dosis recomendadas para el cultivo de camote, lo cual resulto en seis tratamientos: testigo (sin fertilizacion organica), estiercol de ganado (20 t·ha-1), pollinaza (10 t·ha-1), compost A (1.5 t·ha-1), compost B (1.5 t·ha-1) y compost C (0.375 t·ha-1). En los primeros cuatro experimentos, los productos y dosis recomendadas se definieron en orden de eficiencia de produccion: pollinaza (dosis entre 13 y 20 t·ha-1) > estiercol de ganado (dosis entre 30 y 40 t·ha-1) > compost B (dosis entre 0.75 y 2.25 t·ha-1) = compost A (dosis entre 2.25 y 3.00 t·ha-1). Con el quinto experimento se concluyo que: 1) la pollinaza fue el fertilizante inicial mas adecuado para el cultivo de camote en suelos de la sabana y 2) el rendimiento del camote estuvo vinculado directamente a la masa de las raices comerciales, el numero de raices comerciales y la productividad de tallos; las cuales, a su vez, fueron maximizadas al incrementar la materia organica y las cantidades de fosforo en el suelo