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Dificuldades de aprendizagem em estequiometria: uma proposta de ensino apoiada na modelagem
(Universidade Federal do Rio Grande do NorteBRUFRNPrograma de Pós-Graduação em Ensino de Ciências Naturais e MatemáticaEnsino de Ciências Naturais e Matemática, 2013-07-30)
In order to learn/teach chemistry some themes are relevant, like the stoichiometry,
which consists in the study of the weight ratios in the combination of elements and
compounds between themselves. This is an underlying ...
Involvement of soluble proteins in growth and metabolic adjustments of drought-stressed Calligonum mongolicum seedlings under nitrogen addition
(Wiley Blackwell Publishing, Inc, 2020-10)
The planting of seedlings is the most effective measure for vegetation restoration. However, this practice is challenging in desert ecosystems where water and nutrients are scarce. Calligonum mongolicum is a sand-fixing ...
The role of surface stoichiometry in NO2gas sensing using single and multiple nanobelts of tin oxide
(2021-04-28)
Typically used semiconducting metal oxides (SMOs) consist of several varying factors that affect gas sensor response, including film thickness, grain size, and notably the grain-grain junctions within the active device ...
Synthesis, characterization and thermal study of solid mandelate of some bivalent transition metal ions in CO2 and N2 atmospheres
(2013-01-01)
Solid state M-L, where M stands for bivalent transition metals (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)) and L is mandelate, were synthesized. Simultaneous thermogravimetry and differential scanning calorimetry, ...
Intrinsic magnetic properties of BixCo2-xMnO 4 spinels obtained by short-time etching
(2013-08-01)
We report the structural and magnetic properties of Co2MnO 4, partially substituted by Bi at the octahedral site. Bismuth enhances ferromagnetism due to a decrease of the Co2+-Co2+ antiferromagnetic interactions and an ...
Synthesis, characterization and thermal study of solid mandelate of some bivalent transition metal ions in CO2 and N2 atmospheres
(2013-01-01)
Solid state M-L, where M stands for bivalent transition metals (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)) and L is mandelate, were synthesized. Simultaneous thermogravimetry and differential scanning calorimetry, ...
Intrinsic magnetic properties of BixCo2-xMnO 4 spinels obtained by short-time etching
(2013-08-01)
We report the structural and magnetic properties of Co2MnO 4, partially substituted by Bi at the octahedral site. Bismuth enhances ferromagnetism due to a decrease of the Co2+-Co2+ antiferromagnetic interactions and an ...
Stoichiometric homeostasis in the food web of a chronically nutrient-rich stream
(University of Chicago Press, 2014-06)
The theory of ecological stoichiometry holds that heterotrophs are mostly homeostatic and exhibit less variation in body stoichiometry than do autotrophs. Most studies of stream foodweb stoichiometry have been done in ...
Stoichiometry of sulfite oxidation by oxygen during the determination of the volumetric mass transfer coefficient
(American Chemical Society, 2008-12)
The aim of this work was to study the effect of the initial sulfite concentration on the stoichiometric coefficient of sulfite oxidation. A combined method based on the oxidation of sulfite by oxygen in the presence of ...