30 documents found, page 1 of 3

Movimento Química pós 2022: construção de um plano de ação para que a Química e...

Considering the bicentenary of Brazil’s Independence in 2022 and that this year was proclaimed by UNESCO as the International Year of Basic Sciences for Sustainable Development, in mid-2021 the Brazilian Chemical Society (SBQ) launched the “Post 2022 Chemistry Movement - Sustainability and Sovereignty”, with the main goal of promoting different activities so that chemistry contributes for the sustainable develo...

NPK: ESSENTIALS FOR SUSTAINABILITY

Human population growth and development has been largely dependent on non-renewable natural resources, which cannot be indefinitely sustained. Beyond, coal and other abundant resources cannot continue to be used at current rates due to their impact on the environment and climate. It is thus important to replace as much as possible the fossil fuels and scarce minerals as sources of energy and industrial raw mate...

EVOLUÇÃO E INOVAÇÃO NO SETOR QUÍMICO BRASILEIRO: UMA VISÃO DOS ÚLTIMOS QUARENTA...

The Brazilian chemical community shows positive characteristics that improved significantly during the past forty years: the scientific output is substantial, it contributes positively to the position of this country in the innovation rankings, the chemical companies create and export technologies and the larger share of post-graduates employed by the Brazilian industry works in chemical or chemistry-based comp...

Multifunctional Nanocomposites between Different Carbon Nanostructures and Styr...

This work describes the preparation, characterization and properties study of multifunctional nanocomposites between poly(styrene-co -butyl acrylate) latex and different carbon nanostructures: iron-filled carbon nanotubes (CNT), graphene or graphene oxide. Different approaches were employed to prepare stable aqueous dispersions of these nanostructures, according to the specificity of each nanomaterial. The nano...

Electrified Water: Liquid, Vapor and Aerosol

Many reports associate electrostatic charge in dielectrics with water, either bulk, finely dispersed in aerosol or as atmospheric vapor. Two widespread but currently controversial assumptions relevant to this topic are the prevalence of electroneutrality and the passive role of water in electrical phenomena, dissipating charge due to its significant electrical conductivity. Early reports from Faraday, Kelvin an...

Metal nanostructures with magnetic and biodegradable properties for medical app...

Gold nanoparticles (AuNPs) were synthesized by reduction of HAuCl4 with NaBH4 or l-ascorbic acid and they were stabilized with cysteine, cysteamine and a thiol-capped PEG. A nanocomposite was prepared by the addition of polylactic acid (PLA) acetone solutions to aqueous AuNP dispersions, resulting in PLAs enclosing AuNPs. Superparamagnetic iron oxide nanoparticles (SPION) modified with Au on the surface (SPION@...

Inovação para a sustentabilidade

The transition to sustainable standards of production and consumption within a scenario of decreased availability of natural resources, growing population and climate change is essential to meet current challenges facing mankind. A strategy to meet these challenges should contain elements different from current approaches for industrial production. This work concentrates on the possibilities for the intensive u...

Química sem fronteiras

The main objective of this paper is to start and stimulate reflection, discussion and proposing actions that allow Chemistry in Brazil contribute to a prosperous, safer and better future for the nation.

Alchemy in the 21st century

Fracionamento de polifosfato de sódio e caracterização por RMN de 31P: um exper...

This text describes an experiment on fractional precipitation of a polymer together with determination of average degree of polymerization by NMR. Commercial sodium polyphosphate was fractionated by precipitation from aqueous solution by adding increasing amounts of acetone. The polydisperse salt and nine fractions obtained from it were analyzed by 31P Nuclear Magnetic Resonance and the degree of polymerization...