Effects of Aluminum Sulfate and Polyelectrolyte Solutions on the Geotechnical Properties of Organic Clay

This paper intends to produce a compendium of geotechnical properties of major problem soils of Nigeria which have critical influence on the design, performance, lifespan, construction cost and maintenance of civil engineering structures. Apart from the well researched lateritic soils of Nigeria, the black cotton soils (BCS) of north-eastern Nigeria, clay shale of north-western Nigeria, organic clay prominent in Lagos and soft sedimentary deposits of the Niger-Delta areas of Nigeria are also considered. Significant geotechnical properties of major problem soils in Nigeria were discovered to be scattered in different publications, magazines, journals, conference proceedings, research papers etc. Consequently, it is the aim of this paper to collate, correlate, analyze and digitize these important geotechnical properties on digital map of Nigeria. A Geographic Information System (GIS) mapping software called ArcGIS will be used to generate isopleths in form of contours for these soil properties on map of Nigeria.

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OPTIMIZATION OF PROCESS FOR TOTAL RECOVERY OF ALUMINUM FROM SMELTING SLAG 2. REMOVAL OF ALUMINUM SULFATE

Environmental Engineering and Management Journal ◽

10.30638/eemj.2014.002 ◽

2013 ◽

Vol 13 (1) ◽

pp. 7-14 ◽

Cited By ~ 2

Author(s):

Romanita Teodorescu ◽

Viorel Badilita ◽

Maria Roman ◽

Victoria Purcaru ◽

Petre Capota ◽

...

Keyword(s):

Aluminum Sulfate ◽

Total Recovery ◽

Smelting Slag

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Geotechnical Properties of Tidal Flat Muds: Responses to Tangential and Normal Stresses

10.21236/ada540427 ◽

2011 ◽

Author(s):

Bernard P. Boudreau ◽

Bruce D. Johnson ◽

Paul S. Dill

Keyword(s):

Tidal Flat ◽

Geotechnical Properties ◽

Normal Stresses

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Donnan Equilibria in Polymeric Micellar Systems with Weak Polyelectrolyte Shells: The Lowering of the pH Value

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19971730 ◽

1997 ◽

Vol 62 (11) ◽

pp. 1730-1736 ◽

Cited By ~ 4

Author(s):

Petr Munk ◽

Zdeněk Tuzar ◽

Karel Procházka

Keyword(s):

Ionic Strength ◽

Block Copolymer ◽

Ph Value ◽

Electrolyte Solutions ◽

Hydrogen Ions ◽

Micellar Systems ◽

Weak Electrolytes ◽

Block Copolymer Micelles ◽

Copolymer Micelles ◽

Polyelectrolyte Solutions

When two electrolyte solutions are separated and only some of the ions can cross the boundary, the concentrations of these ions are different on both sides of the boundary. This is the well-known Donnan effect. When weak electrolytes are involved, the imbalance includes also hydrogen ions: there is a difference of pH across the boundary and the dissociation of nondiffusible weak electrolytes is suppressed. The effect is very pronounced when the concentration of the weak electrolyte is high and ionic strength is low. The significance of this phenomenon is discussed for polyelectrolyte solutions, and particularly for block copolymer micelles with weak polyelectrolyte shells. The effect is quite dramatic in the latter case.

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Preparation of Strong Acid Catalysts by Sulfate Treatment of Calcined Boehmite

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922241 ◽

1992 ◽

Vol 57 (11) ◽

pp. 2241-2247 ◽

Cited By ~ 2

Author(s):

Tomáš Hochmann ◽

Karel Setínek

Keyword(s):

Catalytic Activity ◽

Surface Area ◽

Aluminum Sulfate ◽

Solid Acid ◽

Strong Acid ◽

Acid Strength ◽

Solid Acid Catalysts ◽

Acid Catalysts ◽

Preparation Methods ◽

Indicator Method

Solid acid catalysts with acid strength of -14.52 < H0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105-800 °C. Two preparation methods were used: impregnation of the calcined boehmite with 3.5 M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650 °C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerization of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.

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Bottlebrush polymers in the melt and polyelectrolytes in solution share common structural features

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1916362117 ◽

2020 ◽

Vol 117 (10) ◽

pp. 5168-5175 ◽

Cited By ~ 4

Author(s):

Joel M. Sarapas ◽

Tyler B. Martin ◽

Alexandros Chremos ◽

Jack F. Douglas ◽

Kathryn L. Beers

Keyword(s):

Neutron Scattering ◽

Correlation Length ◽

Salt Concentration ◽

Polymer Concentration ◽

Structural Features ◽

Peak Position ◽

Correlation Peak ◽

Grafting Density ◽

Scattering Measurements ◽

Polyelectrolyte Solutions

Uncharged bottlebrush polymer melts and highly charged polyelectrolytes in solution exhibit correlation peaks in scattering measurements and simulations. Given the striking superficial similarities of these scattering features, there may be a deeper structural interrelationship in these chemically different classes of materials. Correspondingly, we constructed a library of isotopically labeled bottlebrush molecules and measured the bottlebrush correlation peak position q*=2π/ξ by neutron scattering and in simulations. We find that the correlation length scales with the backbone concentration, ξ∼cBB−0.47, in striking accord with the scaling of ξ with polymer concentration cP in semidilute polyelectrolyte solutions (ξ∼cP−1/2). The bottlebrush correlation peak broadens with decreasing grafting density, similar to increasing salt concentration in polyelectrolyte solutions. ξ also scales with sidechain length to a power in the range of 0.35–0.44, suggesting that the sidechains are relatively collapsed in comparison to the bristlelike configurations often imagined for bottlebrush polymers.

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