Specific Gravity of Aluminum Sulfate Solutions.

1945 ◽  
Vol 37 (10) ◽  
pp. 1016-1018 ◽  
Author(s):  
J. W. Silve ◽  
J. E. Chenevey
2020 ◽  
Vol 8 (1) ◽  
pp. 313
Author(s):  
Rodrigo Roso ◽  
Ubirajara Russi Nunes ◽  
Caren Alessandra Müller ◽  
Juçara Terezinha Paranhos ◽  
Sidinei José Lopes ◽  
...  

The objetive of this study was to identify the effects of aluminum concentrations and pH levels of solution on germination of Echium plantagineum L. seeds. Three different experiments were carried out in completely randomized design with four repetitions. In the first experiment, we used aluminum sulfate solutions in concentrations of 0.0; 0.3; 0.6; 1.0; 2.0; 3.0; 4.0; 5.0; 6.0 and 7.0 cmolc L-1 and in the second experiment, solutions with different pH, 3.0; 4.0; 5.0; 6.0; 7.0; 8.0; 9.0 and 10.0. In the third experiment, we carried out a factorial (4x4) with aluminum sulfate solutions (0.0; 2.0; 4.0 and 6.0 cmolc L-1) and pH (4.0; 5.0; 6.0 and 7.0). It was evaluated the germination of Echium plantagineum L. at four and 14 days after seeding (DAS), germination speed index, primary root length, aerial part and dry mass of seedlings. The presence of aluminum reduced the germination by 27 and 40% at four and 14 DAS, respectively, in concentrations superior to 3.0 cmolc L-1. The three growth parameters presented linear reduction with the increase of aluminum concentrations. In the second experiment, the solutions with pH of 3.0 and 10.0 provided increases in germination, length of root and aerial part, and little influence in the dry mass of seedlings. In the third experiment, there was significant interaction between the aluminum concentrations and pH levels of substrate. The presence of aluminum in the substrate presented toxic effect on germination of seeds, length of seedlings and dry mass. The pH of the solution has little effect in germination of seeds and in the growth of seedlings of E. plantagineum.


2021 ◽  
Vol 94 (6) ◽  
pp. 813-817
Author(s):  
A. A. Blokhin ◽  
Yu. V. Murashkin ◽  
M. A. Mikhaylenko

Author(s):  
A. Howie ◽  
D.W. McComb

The bulk loss function Im(-l/ε (ω)), a well established tool for the interpretation of valence loss spectra, is being progressively adapted to the wide variety of inhomogeneous samples of interest to the electron microscopist. Proportionality between n, the local valence electron density, and ε-1 (Sellmeyer's equation) has sometimes been assumed but may not be valid even in homogeneous samples. Figs. 1 and 2 show the experimentally measured bulk loss functions for three pure silicates of different specific gravity ρ - quartz (ρ = 2.66), coesite (ρ = 2.93) and a zeolite (ρ = 1.79). Clearly, despite the substantial differences in density, the shift of the prominent loss peak is very small and far less than that predicted by scaling e for quartz with Sellmeyer's equation or even the somewhat smaller shift given by the Clausius-Mossotti (CM) relation which assumes proportionality between n (or ρ in this case) and (ε - 1)/(ε + 2). Both theories overestimate the rise in the peak height for coesite and underestimate the increase at high energies.


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