Static exclusion method for determination of specific pore volume

1984 ◽  
Vol 56 (11) ◽  
pp. 1781-1785 ◽  
Author(s):  
Wei. Cheng
Keyword(s):  
Pore Volume ◽  
Specific Pore Volume ◽  
Exclusion Method

Titrimetric and gravimetric determination of the specific pore volume of microparticulate silica gels

1988 ◽  
Vol 53 (2) ◽  
pp. 269-277 ◽  
Author(s):  
Zdeněk Šimek ◽  
Radim Vespalec ◽  
Jiří Neča
Keyword(s):  
Pore Volume ◽  
Barometric Pressure ◽  
Point Of View ◽  
The Other ◽  
Silica Gels ◽  
Specific Pore Volume ◽  
Gravimetric Determination ◽  
Relative Standard ◽  
Gravimetric Procedure

The titrimetric and gravimetric methods of determination of the specific pore volume were studied unmodified and modified chromatographic silica gels of mean particle size above 5 μm. The apparatus and titrimetric procedure suggested elsewhere were adapted so that the relative standard deviation of measurement did not exceed 2%. Water, n-octane, and methanol were used as titrants, and methanol was found to suit best from the point of view of accuracy and rapidity of analysis and versatility of use. This solvent is also suitable for the gravimetric measurements, which can be carried out without thermostatting and at barometric pressure. The titrimetric procedure is less time consuming than the gravimetric procedure which, on the other hand, is less tedious and less instrumentation-demanding.

scholarly journals Titanium Carbide Nanocrystals Synthesized from a Metatitanic Acid-Sucrose Precursor via a Carbothermal Reduction

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Hyunho Shin ◽  
Jun-Ho Eun
Keyword(s):  
Process Control ◽  
Titanium Carbide ◽  
Specific Surface ◽  
Surface Area ◽  
Pore Volume ◽  
Carbothermal Reduction ◽  
Crystal Size ◽  
Reduction Process ◽  
Specific Pore Volume ◽  
Metatitanic Acid

A TiC powder is synthesized from a micron-sized mesoporous metatitanic acid-sucrose precursor (precursor M) by a carbothermal reduction process. Control specimens are also prepared using a nanosized TiO2-sucrose precursor (precursor T) with a higher cost. When synthesized at 1500°C for 2 h in flowing Ar, the characteristics of the synthesized TiC from precursor M are similar to those of the counterpart from precursor T in terms of the crystal size (58.5 versus 57.4 nm), oxygen content (0.22 wt% versus 0.25 wt%), and representative sizes of mesopores: approximately 2.5 and 19.7–25.0 nm in both specimens. The most salient differences of the two specimens are found in the TiC from precursor M demonstrating (i) a higher crystallinity based on the distinctive doublet peaks in the high-two-theta XRD regime and (ii) a lower specific surface area (79.4 versus 94.8 m2/g) with a smaller specific pore volume (0.1 versus 0.2 cm3/g) than the counterpart from precursor T.

Soil compaction and cotton growth on a vertisol

Soil Research ◽  
1990 ◽  
Vol 28 (6) ◽  
pp. 869 ◽  
Author(s):  
D Mcgarry
Keyword(s):  
Pore Volume ◽  
Soil Profile ◽  
Soil Compaction ◽  
Soil Structure ◽  
Growth Yield ◽  
Root Systems ◽  
Cotton Crop ◽  
Specific Pore Volume ◽  
Structure Degradation ◽  
Seedbed Preparation

Differences in growth, yield and root systems of two adjoining cotton crops on a Vertisol near Dalby, Queensland, were explained in terms of soil profile morphology and soil shrinkage indices. The soil beneath the strongly inferior crop had platy structure in the 0.05-0.28 m layer and significantly less air-filled specific pore volume in the 0.2-0.4 m layer. This soil structure degradation was caused by seedbed preparation of wet soil, prior to sowing the cotton crop.

Corrigenda - Soil compaction and cotton growth on a vertisol

Soil Research ◽  
1990 ◽  
Vol 28 (6) ◽  
pp. 869
Author(s):  
D Mcgarry
Keyword(s):  
Pore Volume ◽  
Soil Profile ◽  
Soil Compaction ◽  
Soil Structure ◽  
Growth Yield ◽  
Root Systems ◽  
Cotton Crop ◽  
Specific Pore Volume ◽  
Structure Degradation ◽  
Seedbed Preparation

Differences in growth, yield and root systems of two adjoining cotton crops on a Vertisol near Dalby, Queensland, were explained in terms of soil profile morphology and soil shrinkage indices. The soil beneath the strongly inferior crop had platy structure in the 0.05-0.28 m layer and significantly less air-filled specific pore volume in the 0.2-0.4 m layer. This soil structure degradation was caused by seedbed preparation of wet soil, prior to sowing the cotton crop.

scholarly journals Fractal Dimensions of Cell Wall in Growing Cotton Fibers

2020 ◽  
Vol 4 (1) ◽  
pp. 6
Author(s):  
Michael Ioelovich
Keyword(s):  
Cell Wall ◽  
Fractal Dimension ◽  
Apparent Density ◽  
Pore Volume ◽  
Dimensional Space ◽  
Fractal Dimensions ◽  
Primary Cell ◽  
Primary Cell Wall ◽  
Cotton Fibers ◽  
Specific Pore Volume

In this research, fractal properties of a cell wall in growing cotton fibers were studied. It was found that dependences of specific pore volume (P) and apparent density (ρ) on the scale factor, F = H/h, can be expressed by power-law equations: P = Po F(Dv−E) and ρ = ρo F(E−Dρ), where h is minimum thickness of the microfibrilar network in the primary cell wall, H is total thickness of cell wall in growing cotton, Dv = 2.556 and Dρ = 2.988 are fractal dimensions. From the obtained results it follows that microfibrilar network of the primary cell wall in immature fibers is loose and disordered, and therefore it has an increased pore volume (Po = 0.037 cm3/g) and low density (ρo = 1.47 g/cm3). With enhance days post anthesis of growing cotton fibers, the wall thickness and density increase, while the pore volume decreases, until dense structure of completely mature fibers is formed with maximum density (1.54 g/cm3) and minimum pore volume (0.006 cm3/g). The fractal dimension for specific pore volume, Dv = 2.556, evidences the mixed surface-volume sorption mechanism of sorbate vapor in the pores. On the other hand, the fractal dimension for apparent density, Dρ = 2.988, is very close to Euclidean volume dimension, E = 3, for the three-dimensional space.

scholarly journals Cu(II) immobilization onto a one-step synthesized poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) resin: Kinetics and XPS analysis

2016 ◽  
Vol 70 (1) ◽  
pp. 9-19
Author(s):  
Danijela Maksin ◽  
Aleksandra Nastasovic ◽  
Tatjana Maksin ◽  
Zvjezdana Sandic ◽  
Katja Loos ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Photoelectron Spectroscopy ◽  
Pore Volume ◽  
Pore Diameter ◽  
Mercury Porosimetry ◽  
Ethylene Glycol Dimethacrylate ◽  
Sorption Behavior ◽  
Glycol Dimethacrylate ◽  
Inert Component ◽  
Specific Pore Volume

Synthesis of an unconventional resin based on 4-vinylpyridine (4-VP) and its Cu(II) sorption behavior were studied. Three samples of macroporous crosslinked poly(4-vinylpyridine-co-ethylene glycol dimethacrylate) [P4VPE] with different porosity parameters were prepared by suspension copolymerization by varying the n-heptane amount in the inert component. The samples were characterized by mercury porosimetry, elemental analysis and x-ray photoelectron spectroscopy (XPS). The sorption of P4VPE for Cu(II) ions, determined under non-competitive conditions, was relatively rapid, i.e. the maximum capacity was reached within 30 min. The maximum experimental sorption capacity for the sample with the highest values of pore diameter and specific pore volume (Sample 3, Qeq = 89 mg g-1) was 17.5 times higher than for the sample with the lowest values of pore diameter and specific pore volume (Sample 1, Qeq = 5.1 mg g-1). Since the values for pyridine content in all P4VPE samples were almost the same, it was concluded that the porosity parameters have predominant influence on Cu(II) sorption rates on P4VPE. The sorption behavior and the rate-controlling mechanisms were analyzed using six kinetic models (pseudo-first order, pseudo-second order, Elovich, intraparticle diffusion, Bangham and Boyd models). XPS study clarified the nature of the formed P4VPE-Cu(II) species.

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