Results 121 to 130 of about 152,353 (242)

Desenvolvimento Desigual

Boletim Gaúcho de Geografia, 2013
O livro trata a respeito da teoria do desenvolvimento desigual. Com herança marxissta, a obra é fundamentada e orientada para explicar a estrutura econômica, política e social da sociedade. O autor procura revelar melhor a geografia do capitalismo, onde há uma necessidade de igualar e diferenciar espaços.
openaire   +2 more sources

Rh‐Catalyzed [2 + 2 + 2] Cycloaddition of Linked Bis(Diynes) Ar‐C≡C‐C≡C‐(CH2)3‐C≡C‐C≡C‐Ar With Quinones: Synthesis and Photophysical Properties of Bis(Arylethynyl)‐Naphthoquinones and Anthraquinones

Chemistry – A European Journal, EarlyView.
We report the synthesis bis(arylethynyl)naphtho‐ and anthraquinones via Rh(I)‐catalyzed [2 + 2 + 2] cycloaddition reactions. The substrate scope of both quinones and linked bis‐diynes was explored. Microwave irradiation remarkably enhanced yields.
Luana A. Machado, Jianhua Han, Fábio G. Delolo, Joyce C. Oliveira, Breno U. Abreu, Hállen D. R. Calado, Joannes Krebs, Leibo Tan, Qing Ye, Tobias Groß, Christoph Lambert, Camille Latouche, Abdou Boucekkine, Jean‐François Halet, Holger Braunschweig, Todd B. Marder, Eufrânio N. da Silva Júnior   +16 more
wiley   +1 more source

Precipitation of niobic acid from potassium niobate in sulphuric acid solution: A route to niobium oxide

The Canadian Journal of Chemical Engineering, EarlyView.
Graphical abstract illustrating the niobic acid precipitation process applied and the product obtained. Abstract This study investigates the precipitation of niobic acid (Nb2O5.nH2O) from potassium niobate solution with addition of sulphuric acid, and its subsequent thermal conversion into niobium oxide (Nb2O5). Thermodynamic modelling with PHREEQC and
Cássia R. Souza, Gabriela C. Silva, Isabel P. Silva, Frederico M. Penha, Sônia D. F. Rocha   +4 more
wiley   +1 more source

Innovative electrospun geopolymer/zeolite/PVA composite membranes

The Canadian Journal of Chemical Engineering, EarlyView.
Proposed scheme of gas adsorption mechanisms on electrospun geopolymer/zeolite/PVA composite membranes. Abstract Innovative electrospun poly(vinyl alcohol) (PVA)–geopolymer–zeolite 13X composite membranes were successfully fabricated and systematically characterized.
Mariana Schneider, Mar Calzado‐Delgado, Enrique Rodríguez‐Castellón, Maria Olga Guerrero‐Pérez, Dachamir Hotza, Agenor De Noni Junior, Adel Zrelli, Regina de Fátima Peralta Muniz Moreira   +7 more
wiley   +1 more source

Qual desenvolvimento?

Revista Espaço Acadêmico, 2009
RESENHA: POCHMANN, Marcio. Qual Desenvolvimento? Oportunidades e dificuldades do Brasil contemporâneo. São Paulo: Publisher Brasil, 2009, 176p.
openaire   +1 more source

Beyond hydrogen: Process design of a biogas steam reformer for Fischer–Tropsch synthesis

The Canadian Journal of Chemical Engineering, EarlyView.
The effect of pressure and steam to carbon ratio on carbon conversion. Abstract We present an analysis of a pilot‐scale multi‐tubular biogas steam reforming reactor, part of a sustainable aviation fuel (SAF) development project in Brazil. The novelty of this work is the application of a new, validated power law kinetic model, specifically developed for
Rafael Belo Duarte, Rafael Dei Tós Barreto, João Lourenço Castagnari Willimann Pimenta, Luiz Mario de Matos Jorge   +3 more
wiley   +1 more source

DESENVOLVIMENTO ASSISTIDO: DA CHOCADEIRA AO DESENVOLVIMENTO EMBRIONÁRIO [PDF]

, 2019
Kátia Regina Barros da Silva, Eric Santos Acioli da Silva, Yasmin Guedes de Aguiar Pimentel, Karina Dias Alves   +3 more
openaire   +1 more source

SiC/Si ceramic hollow fibres: A new approach to Chlorella vulgaris biomass harvesting

The Canadian Journal of Chemical Engineering, EarlyView.
Abstract Efficient harvesting of microalgae is a critical challenge for the viability of biorefineries, requiring technologies that combine high selectivity, low cost, and scalability. The current work evaluated the performance of an asymmetric hollow fibre ceramic membrane (HF‐SiC70Si30), fabricated by phase inversion and sintered at 1250°C, in the ...
Erisson Paulo Borges Lopes, Warlen Agnelo Dias, Miria Hespanhol Miranda Reis, Vicelma Luiz Cardoso, Fabiana Regina Xavier Batista   +4 more
wiley   +1 more source

Performance comparison of pressure swing adsorption and amine‐based absorption for synthesis gas purification

The Canadian Journal of Chemical Engineering, EarlyView.
Comparison of PSA and amine‐based absorption for syngas purification shows that PSA offers lower energy intensity, global warming potential, and minimum selling price, making it a more sustainable option. However, absorption achieves higher syngas purity. A GREENSCOPE‐based multi‐criteria assessment guides optimal process selection.
Magno Fonseca Santos, Antonio Esio Bresciani, Rita Maria Brito Alves   +2 more
wiley   +1 more source

Tunable amylopectin graft copolymers for flocculating and dewatering iron ore tailings

The Canadian Journal of Chemical Engineering, EarlyView.
Abstract Polyacrylamide (PAM), the standard flocculant for mining tailings, often produces turbid supernatants and poorly dewatered sediments, limiting water reuse and tailings densification. We synthesized amylopectin‐graft‐poly[(2‐methacryloyloxy)ethyl]trimethylammonium chloride (AP‐g‐PMETAC) copolymers with systematically varied graft frequency (N = 
Gustavo P. Zago, Reinaldo Giudici, João B. P. Soares   +2 more
wiley   +1 more source