Silica

In Situ Detection of Opal‐A in Jezero Crater, Mars

“…The amount of hydration reflecting silanol groups, 1.5 ± 0.2 wt. %, is consistent with a typical opal‐A hydroxylation (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). The lower total hydration reflects the lower molecular water concentration, suggesting that partial dehydration may occur under Martian conditions (Chauviré et al., 2021; Rapin et al., 2018; Sun & Milliken, 2018).…”

“…% for opal‐C/CT. Therefore, opal‐A generally contained a higher concentration of silanols, consistent with earlier reports (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). We were not able to estimate silanol concentration in two opal‐C/T samples, presumably because silanol concentrations were <0.1 wt.…”

In Situ Detection of Opal‐A in Jezero Crater, Mars

“…The amount of hydration reflecting silanol groups, 1.5 ± 0.2 wt. %, is consistent with a typical opal‐A hydroxylation (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). The lower total hydration reflects the lower molecular water concentration, suggesting that partial dehydration may occur under Martian conditions (Chauviré et al., 2021; Rapin et al., 2018; Sun & Milliken, 2018).…”

“…% for opal‐C/CT. Therefore, opal‐A generally contained a higher concentration of silanols, consistent with earlier reports (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). We were not able to estimate silanol concentration in two opal‐C/T samples, presumably because silanol concentrations were <0.1 wt.…”

Desiccant Films Made of Low-Density Polyethylene with Dispersed Silica Gel—Water Vapor Absorption, Permeability (H2O, N2, O2, CO2), and Mechanical Properties

“…This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g. The specific volume is the sum of the volume of the pores (0.35 cm 3 /g) and the volume of silicon dioxide (0.45 cm 3 /g), i.e., 0.80 cm 3 /g.…”

“…When linearly extrapolated to 100% RH the water vapor absorption is 0.35 g water/g of dry silica gel which equals to a pore volume of 0.35 cm 3 /g of dry silica gel. This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g.…”

Deep core level hard X‐ray photoelectron spectroscopy for catalyst characterization

“…Alumina, silica, and zeolites consisting of various compositions of Al, Si, and O are typical catalyst supports 15,18,26 . Despite their apparent chemical similarity, they provide great versatility of applications affecting adsorptive and reactive properties 27–29 . Even alumina and silica have various allotropes and specific surface sites alterating the catalytic properties 30–32 .…”

In Situ Detection of Opal‐A in Jezero Crater, Mars

“…The amount of hydration reflecting silanol groups, 1.5 ± 0.2 wt. %, is consistent with a typical opal‐A hydroxylation (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). The lower total hydration reflects the lower molecular water concentration, suggesting that partial dehydration may occur under Martian conditions (Chauviré et al., 2021; Rapin et al., 2018; Sun & Milliken, 2018).…”

“…% for opal‐C/CT. Therefore, opal‐A generally contained a higher concentration of silanols, consistent with earlier reports (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). We were not able to estimate silanol concentration in two opal‐C/T samples, presumably because silanol concentrations were <0.1 wt.…”

Desiccant Films Made of Low-Density Polyethylene with Dispersed Silica Gel—Water Vapor Absorption, Permeability (H2O, N2, O2, CO2), and Mechanical Properties

“…This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g. The specific volume is the sum of the volume of the pores (0.35 cm 3 /g) and the volume of silicon dioxide (0.45 cm 3 /g), i.e., 0.80 cm 3 /g.…”

“…When linearly extrapolated to 100% RH the water vapor absorption is 0.35 g water/g of dry silica gel which equals to a pore volume of 0.35 cm 3 /g of dry silica gel. This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g.…”

Deep core level hard X‐ray photoelectron spectroscopy for catalyst characterization

“…Alumina, silica, and zeolites consisting of various compositions of Al, Si, and O are typical catalyst supports 15,18,26 . Despite their apparent chemical similarity, they provide great versatility of applications affecting adsorptive and reactive properties 27–29 . Even alumina and silica have various allotropes and specific surface sites alterating the catalytic properties 30–32 .…”

In Situ Detection of Opal‐A in Jezero Crater, Mars

“…The amount of hydration reflecting silanol groups, 1.5 ± 0.2 wt. %, is consistent with a typical opal‐A hydroxylation (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). The lower total hydration reflects the lower molecular water concentration, suggesting that partial dehydration may occur under Martian conditions (Chauviré et al., 2021; Rapin et al., 2018; Sun & Milliken, 2018).…”

“…% for opal‐C/CT. Therefore, opal‐A generally contained a higher concentration of silanols, consistent with earlier reports (Day & Jones, 2008; Flörke et al., 2008; Segnit et al., 1965). We were not able to estimate silanol concentration in two opal‐C/T samples, presumably because silanol concentrations were <0.1 wt.…”

Desiccant Films Made of Low-Density Polyethylene with Dispersed Silica Gel—Water Vapor Absorption, Permeability (H2O, N2, O2, CO2), and Mechanical Properties

“…This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g. The specific volume is the sum of the volume of the pores (0.35 cm 3 /g) and the volume of silicon dioxide (0.45 cm 3 /g), i.e., 0.80 cm 3 /g.…”

“…When linearly extrapolated to 100% RH the water vapor absorption is 0.35 g water/g of dry silica gel which equals to a pore volume of 0.35 cm 3 /g of dry silica gel. This value is within the range of literature values, with 0.40 to 0.43 cm 3 pore volume/g of dry silica gel [47]. Silicon dioxide has a density of 2.2 g/cm 3 [47,49,55,56] and has therefore a specific volume of 0.45 cm 3 /g.…”

Deep core level hard X‐ray photoelectron spectroscopy for catalyst characterization

“…Alumina, silica, and zeolites consisting of various compositions of Al, Si, and O are typical catalyst supports 15,18,26 . Despite their apparent chemical similarity, they provide great versatility of applications affecting adsorptive and reactive properties 27–29 . Even alumina and silica have various allotropes and specific surface sites alterating the catalytic properties 30–32 .…”