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A review on the design and application of bi-functionalized adsorbents to remove different pollutants from water.
No full textThis review provides a bibliometric analysis of chemically bi-functionalized materials that have been employed
as advanced adsorbents to remove various types of organic and/or inorganic (cationic and/or anionic) pollutants
from water and wastewater. The relevance of regeneration and reuse experiments for bi-functionalized adsorbents is discussed, since they have been shown to be fundamental in advancing the technology readiness level
(TRL) and for assessing technical, economic, and environmental feasibility. Only 56% of the studies compiled in
this review carried out regeneration and reuse experiments, and few studies have proposed and discussed waste
management of adsorbents after depletion of their adsorption capacity. The aim of the present critical analysis is
to inform and encourage researchers in this field, given the lack of in-depth information in the literature concerning advanced materials especially designed for the simultaneous removal of different types of pollutants
coexisting in complex aqueous matrices in various environments, which slows transfer of the technology to the
market. Among the compiled support materials, the most investigated were silica-based (~46%), followed by
polymers (~15%) and biomass (~11%), with the adsorption capacity (Qmax) of bi-functionalized adsorbents
outperforming mono-functionalized adsorbents, in most cases. For inorganic pollutants, the highest and lowest
Qmax values of 4.67 and 1.51 mmol g− 1 for Cr(VI) were reported for polymer- and silica-based adsorbents,
respectively. Biomass- and xerogel-based adsorbents were the most efficient for organic compounds, with Qmax
values of 39.2 and 2.61 mmol g− 1 for trichloroacetic acid and methylene blue, respectively. In summary, the
results were promising, but advances are still needed, since most of the developed technologies presented low
TRL of ≤4, representing a challenge for transition of the technologies to the pilot scale (TRL ≥ 6) or for transfer
to the market
Does monetary policy impact CO2 emissions? : a GVAR analysis.
No full textThis paper studies the relationship between monetary policy and CO2 emissions. Our contribution is twofold: (i)
we present a stylized dynamic AD-AS model with Global Value Chains (GVC) and carbon emissions to illustrate
this relationship, (ii) we estimate the effect of monetary policy on emissions using the GVAR methodology, which
explicitly considers the interconnection between regions instead of treating them as isolated economies. We focus
on CO2 emissions in four regions: U.S., U.K., Japan and the Eurozone, but we use data from 8 other countries to
characterize the international economy. Our results show that a monetary contraction in a country is associated
with lower domestic emissions both in the short- and the long-run. Although we do not find evidence of cross-
region effects concerning monetary policy, variance decomposition suggests that external factors are relevant to
understanding each region’s fluctuations in emissions
Aplicación de la solución al problema de agrupamiento con restricciones para determinar la condición de estabilidad de taludes de mina.
No full textEste artigo apresenta uma aplicação do método Biased Random Key Genetic Algorithm (BRKGA) ao problema de
agrupamentos com restrição. A solução deste problema retorna a separação de um conjunto de dados em
agrupamentos, tal que os membros de cada agrupamento sejam similares entre si, respeitando as restrições dos dados.
Os dados utilizados são de 88 taludes de minas localizados em diversos países do mundo. Através da solução do
problema de agrupamentos com restrições, busca-se determinar a condição de estabilidade de taludes de minas por
meio das suas características geomecânicas. Neste contexto, espera-se que o método possa ser utilizado e aplicado em
empreendimentos mineiros de pequeno a grande porte.This paper presents an application of the Biased Random Key Genetic Algorithm (BRKGA) method to the
constrained clustering problem. The solution to this problem returns the separation of a set of data into clusters, such
that the members of each cluster are similar to each other, respecting the constraints of the data. The data used are
from 88 mine slopes located in different countries around the world. Solving the constrained clustering problem, we
seek to determine the stability condition of mine slopes through their geomechanical characteristics. In this context,
we hope that the method can be used and applied in small and large mining projects
The aesthetics of the contradictory in the criminal procedure : a vision through (from) the feminine.
No full textEste ensaio, um recorte de uma pesquisa em andamento cujo eixo central é o estudo da estética no sistema de justiça criminal, tem como objetivo apresentar uma revisão do princípio do contradi- tório, pilar fundamental do processo penal. Pretende-se demonstrar a necessidade de reconhecer a plasticidade desse princípio como meio de viabilizar a participação efetiva de pessoas vulneráveis no proces- so, seja na condição de acusadas, vítimas ou testemunhas. A pesquisa adota a estética como estratégia teórica para revelar os erros e desvios da racionalidade processual moderna, propondo uma correção de rumo que permita ao processo penal assegurar os direitos e garantias de todos os indivíduos. Especial atenção é dada à violência do pro- cesso penal em relação às pessoas vulneráveis, marcada pela incapa- cidade de compreender o “outro” em sua diversidade e pluralidade. Busca-se ressignificar os marcos teóricos do processo penal através de uma perspectiva estética baseada no olhar feminino, permitindo que a cena processual seja inclusiva, especialmente para aqueles que não se enquadram no núcleo heteronormativo. Ao conectar, por meio da estética, o mundo do sensível, o estudo visa identificar como a plas- ticidade do princípio do contraditório, compreendida sob a ótica fe- minina, pode superar o desafio de garantir uma participação plural e multiversa no processo penal.This essay, which forms part of an ongoing research pro- ject focusing on the study of aesthetics in the criminal justice system, aims to present a review of the adversarial principle, a fundamental pillar of criminal procedure. The aim is to demonstrate the need to recognise the plasticity of this principle as a means of enabling the effective participation of vulnerable people in the process, whether as defendants, victims or witnesses. The research adopts aesthetics as a theoretical strategy to expose the errors and deviations of modern procedural rationality, proposing a course correction that allows the criminal process to ensure the rights and guarantees of all individu- als. Particular attention is paid to the violence of the criminal process against vulnerable people, characterised by an inability to understand the ‘other’ in its diversity and plurality. The aim is to re-signify the theoretical frameworks of the criminal process through an aesthetic perspective based on the female gaze, allowing the trial scene to be inclusive, especially for those who do not fit into the heteronormative nucleus. By linking the world of the sensible through aesthetics, the study aims to show how the plasticity of the adversarial principle, understood from a feminine perspective, can overcome the challenge of ensuring plural and multiversal participation in criminal procee- dings
A eficiência das políticas públicas e o custo da autonomia dos municípios brasileiros.
No full textPurpose: Brazilian federalism is complex. In a country with continental dimensions, with three levels of government (central, state, and local government) and 5,570 municipalities, a federative organization is expected to be complex. The fiscal sustainability of subnational govern- ments is a fundamental pillar of any federative structure. This research aims to verify whether the revenue generated is sufficient to pay for the municipality’s existence. Originality/value: This is a gap in the specialized literature, which usually analyzes municipalities in terms of income or expenditures but not comparing the revenue obtained by economic activity and the cost of the municipality’s existence, the main contribution of this research. Design/methodology/approach: As such, we investigated the capacity of Brazilian municipalities to generate revenues to finance their autono- mies by combining the income linked to the local economic activity with the cost of the existence of each municipality into an autonomy cost index (ACI). Findings: Our analysis reveals that, of those municipalities who provided the data, one in each four does not generate enough revenues to pay for their existence. The results suggest that the ACI of Brazilian munici- palities decreases with the population and business activity. Hence, our autonomy cost index performs worse in Brazil’s North and Northeast regions. This context opens space for a crucial debate and further studies within the scope of Brazilian federalism.Objetivo: O federalismo brasileiro é complexo. Em um país com dimen- sões continentais, com três níveis de governo (central, estadual e local) e 5.570 municípios, espera-se que uma organização federativa seja com- plexa. A sustentabilidade fiscal dos governos subnacionais é um pilar fundamental de qualquer estrutura federativa. O objetivo desta pesquisa é verificar se a receita gerada é suficiente para custear a existência do município. Originalidade/valor: Essa é uma lacuna na literatura especializada, que costuma analisar os municípios em termos de receitas ou despesas, mas não comparando a receita obtida pela atividade econômica com o custo de existência do município, principal contribuição desta pesquisa. Design/metodologia/abordagem: Assim, investigamos a capacidade dos municípios brasileiros de gerar receitas para financiar suas autonomias, combinando a receita vinculada à atividade econômica local com o custo de existência de cada município, em um índice de custo de autonomia (ICA). Resultados: A análise revela que, entre os municípios que forneceram os dados, um em cada quatro não gera receitas suficientes para custear a própria existência. Os resultados sugerem que o custo de autonomia dos municípios brasileiros diminui com a população e a atividade empre- sarial, de forma que nosso ICA apresenta pior desempenho nas regiões Norte e Nordeste do Brasil. Esse contexto abre espaço para um impor- tante debate e novos estudos no âmbito do federalismo brasileiro
Producciones narrativas en la formación por alternancia : un estudio de caso de una estudiante de Licenciatura en Educación del Campo.
No full textAs licenciaturas em Educação do Campo têm como objetivo formar professores e gestores para atuarem por áreas de conhecimento em escolas situadas no campo. Orientadas pelos princípios da Formação por alternância, esse modelo educacional pressupõe planejamento, estudos e levantamento de informações na comunidade e sua socialização entre educandos e professores. Buscamos discutir as similaridades teórico-metodológicas entre a Formação por alternância, a Metodologia das Produções Narrativas e sua aplicação em estudo de caso com uma estudante do curso de Licenciatura em Educação do Campo da Universidade Federal de Viçosa. Foram realizadas entrevistas narrativas sobre os territórios educativos em sua comunidade, refletindo a trajetória pessoal, história local e contexto nacional. A Metodologia das Produções Narrativas contribui para recuperar diferentes sentidos da experiência educativa, compreender as vicissitudes da educação do campo e atualizar experiências enquanto sujeito do campo.The Degree in Countryside Education aims to train teachers and headmasters to work by knowledge areas in countryside ́s schools. They are guided by the principles of alternance formation, an educational model that presupposes planning, studies and information gathering in the community and its socialization between students and teachers. This paper discusses theoretical-methodological similarities between alternance formation and Methodologies of Narrative Productions and its application in a case study with a student of the Degree in Countryside Education of the Universidade Federal de Viçosa. Narrative interviews about the educational territories of her community were conducted, reflecting on the personal trajectory, the local history and the national context. Finally, the MPN helped to recover different senses of the educational experience, to understand the vicissitudes of the countryside education and to update experiences as rural subjects
Flavonoid-incorporated starch and poly(vinyl alcohol) film : sensitive and selective colorimetric sensor for copper identification and quantification in beverages and environmental samples.
No full textColorimetric sensors based on an eco-friendly sensor molecule immobilized into a polymer matrix have broad
applications for detecting trace elements. However, their potential for quantitative analysis of these elements
remains little explored. Here, we incorporated rutin or quercetin into films based on starch, poly(vinyl alcohol),
and glycerol to detect and quantify Cu2+ in different matrices. The films were characterized by colorimetric
assays, thickness, and solubility analyses, scanning electron microscopy (SEM), Fourier transform infrared
spectroscopy (FTIR), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and mechanical as
says. Incorporating the flavonoids in the film decreased its solubility, tensile strength, and modulus of elasticity,
while increased its cross-sectional surface irregularity. XRD and DSC results indicated an increase in film
crystallinity in the presence of rutin or quercetin. FTIR analyses showed a more effective incorporation of
quercetin than rutin in the polymeric matrix, which was confirmed by flavonoid release studies from the film.
The film containing quercetin exhibited selectivity in identifying copper in liquid matrices, changing its color
from light yellow to dark yellow. An analytical method to quantify Cu2+ was developed, presenting a linear
response range of 0.20–1.20 mg L− 1
, with detection and quantification limits of 0.060 and 0.20 mg L− 1
,
respectively, very lower than other methods based on polymeric matrices containing natural dyes. The method
was successfully applied for Cu2+ determination in cachaça and tap water samples, achieving high accuracy
(96–104% of recovery) and precision (relative standard deviation < 6.7%). Our findings represent an
advancement in the field of sensors based on natural dyes, demonstrating that such sensors can achieve high
sensitivity without the need for complex sample preparation methods
