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Mechanical dispersion of clay from soil into water: readily-dispersed and spontaneously-dispersed clay

100%

Czyz E. A., Dexter A. R.

International Agrophysics

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2015

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tom 29

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nr 1

A method for the experimental determination of the amount of clay dispersed from soil into water is described. The method was evaluated using soil samples from agricultural fields in 18 locations in Poland. Soil particle size distributions, contents of organic matter and exchangeable cations were measured by standard methods. Sub-samples were placed in distilled water and were subjected to four different energy inputs obtained by different numbers of inversions (end-over-end movements). The amounts of clay that dispersed into suspension were measured by light scattering (turbidimetry). An empirical equation was developed that provided an approximate fit to the experimental data for turbidity as a function of number of inversions. It is suggested that extrapolation of the fitted equation to zero inversions enables the amount of spontaneously-dispersed clay to be estimated. This method introduces the possibility of replacing the existing subjective, qualitative method of determining spontaneously-dispersed clay with a quantitative, objective method. Even though the disper-sed clay is measured under saturated conditions, soil samples retaina ‘memory’ of the water contents at which they have been stored.

2

Minimization of phenol by natural occurrence adsorbent

86%

Joshi J., Sahu O.

International Letters of Natural Sciences

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2014

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tom 11

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nr 1

Phenol and chlorophenols are long-lived pollutants frequently found in industrial effluents. Phenols are widely used for the commercial production of a wide variety of resins including phenolic resins, epoxy resins and adhesives, and polyamide for various applications. Adsorption process has been proven one of the best water treatment technologies around the world and the removal of diverse types of pollutants from water. However, widespread use of commercial adsorbent is sometimes restricted due to its higher costs. Attempts have been made to develop inexpensive adsorbents utilizing for the reduction of phenol from water. Four types of adsorbent clay, algae, moringa oleifera and rice husk has been used. Among all rice husk shown 97 % of phenol adsorption at 1mm particle size, pH 4, 3 g/l dosing and 150min contact time.

3

Nonlinear dynamic properties of silty clay from Warsaw area

86%

Sas W., Gabrys K., Sobol E., Szymanski A.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2016

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tom 48

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nr 3

4

Small strain stiffness in overconsolidated Pliocene clays

86%

Markowska-Lech K., Lech M., Bajda M., Szymanski A.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2013

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tom 45

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nr 2

A huge development of technical infrastructure, including the construction of many high-rise buildings, roads, railroads and extension of subway lines, took place over the recent years in Poland. Therefore, numerous planned investment projects require geotechnical data documenting the variation of soil parameters found in the subsoil. The shear wave velocity is one of the most important input parameters to represent the stiffness of the soil deposits. This paper focuses on the methods and devices using measurements of the shear wave velocity to estimate the initial shear modulus in cohesive soil. It is preferable to measure VS by in situ wave propagation tests, however it is often economically not feasible in all regions of Poland. Hence, a reliable correlation between shear wave velocity and parameters measured in triaxial cell or static penetration parameters would be a considerable advantage. This study shows results obtained from the bender elements tests and fi eld techniques – seismic cone penetration test and seismic flat dilatometer, performed on overconsolidated cohesive soils in Warsaw. On the basis of the test results possible correlations between shear wave velocity (initial shear modulus), mean effective stress and void ratio are considered and four original empirical relationships are proposed. Moreover, the proposed formulas by two different techniques using triaxial apparatus and also RCPT cone were examined. The proposed formulas show a reasonable agreement with direct shear wave velocity profiles for clays and might be incorporated into routine laboratory and field practice.

5

Boron adsorption in soil as influenced by pH and competing anions

86%

Wojcik P., Wojcik M.

Journal of Fruit and Ornamental Plant Research

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2001

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tom 09

|

nr 1-4

6

Surface heterogeneity effects in water vapour adsorption on clay minerals

86%

Sokolowska Z., Stawinski J., Sokolowski S.

International Agrophysics

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1992

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tom 06

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nr 3-4

7

Ecological, clay-based building engineering

72%

Mankowski P., Krzosek S., Mikolajko M.

Annals of Warsaw University of Life Sciences - SGGW. Forestry and Wood Technology

|

2014

|

tom 85

8

Determination of the heating pile numerical model parameters based on the laboratory strength tests of clay at low temperatures

72%

Piotrowicz B., Jastrzebska M., Lupiezowiec M.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

|

2018

|

tom 50

|

nr 2

9

Determination of undrained shear strength and constrained modulus from DMT for stiff overconsolidated clays

72%

Lechowicz Z., Rabarijoely S., Kutia T.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2017

|

tom 49

|

nr 2

10

Undrained shear strength of the heavily consolidated clay

72%

Strozyk J., Tankiewicz M.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

|

2013

|

tom 45

|

nr 2

The undrained shear strength (cu) is considered one of the most basic parameter characterizing soils in engineering practice. The particular importance of cu is in the case of clayey soil. This parameter also is the basis for the classifi cation of soil according to the ISO standard. The undrained shear strength usually is determined from unconfi ned compression test or from triaxial compression test. In the simple way it can be estimated from the fall cone penetrometer test as index parameter. In the presented work the results of unconfi ned compression tests for very stiff, heavily consolidated clay were shown. All analysed clay specimens were taken from the large depth, up to 303 m below terrain level. The tests results: undrained shear strength (cu) and unconfi ned compression strength (qu) were discussed in the relation on in situ consolidation stress, Atterberg’s limits and the indicatory test – fall cone test results.

11

Measuring the energies of aggregate bonding in soils

72%

So H. B., Yatapanage K., Raine S. R.

Bibliotheca Fragmenta Agronomica

|

1997

|

tom 2B

12

Shrinkage properties of three clay materials at different temperatures

72%

Wysocka A., Stepniewski W., Horn R.

International Agrophysics

|

2006

|

tom 20

|

nr 3

13

Effects of soil management on the dispersibility of clay in a sandy soil

72%

Dexter A. R., Czyz E. A.

International Agrophysics

|

2000

|

tom 14

|

nr 3

14

Effect of non-homogeneity of Pliocene clays in the vicinity of Warsaw and their physical properties

72%

Sobolewski M.

Electronic Journal of Polish Agricultural Universities. Series Civil Engineering

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2003

|

tom 06

|

nr 2

Non-homogeneity of soils is the reason for considerable variability of their properties and the problems related with interpretation of geotechnical parameters at the same time. The paper presents and discusses results of examination of physical properties of Pliocene clays as well as their variability in the profile of an experimental plot in Stegny district, Warsaw. Alogn the thickness, there appear changes in the amount of clay fraction, water content, liqudity index and density of soil within layers of soils. These properties can constitute leading features for the analysis of strength, deformation, filtration, consolidation and other parameters. The determination of the character of changes in these properties gives an opportunity for separating soils behaving in a similar way in the section of the subsoil.

15

Respiration of soil enriched with manure and mineral materials (methodical aspects)

58%

Ksiezopolska A., Wlodarczyk T., Glinski J., Flis-Bujak M.

Polish Journal of Environmental Studies

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2011

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tom 20

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nr 2

Methods of start (as a new one), reactive, basal, and long-term respiration determination in laboratory conditions were used for evaluating Corg transformation with CO2 release from sandy soil (Haplic Luvisol) enriched in field experiments with organic (manure) and mineral (clay, lime) materials. They proved to be useful in such experiments. The objective of the investigation was to find which treatments stimulate or inhibit Corg mineralization. Of all treatments used, the least susceptible to Corg mineralization in soil appeared to be the soil enriched with manure. The most susceptible was soil enriched with soil+manure+clay+lower dose of lime.

16

The evaluation of pliocene clays consistency state with using of flat dilatometer tests

58%

Sobolewski M.

Electronic Journal of Polish Agricultural Universities. Series Civil Engineering

|

2006

|

tom 09

|

nr 4

17

Dynamic and cyclic static loading behavior of silty-sandy clay at small and moderate strains

58%

Gabrys K., Sas W., Sobol E.

Acta Scientiarum Polonorum. Architectura

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2016

|

tom 15

|

nr 4

The shear modulus (G) is one of the key parameters for seismic ground response analysis and it can be usually determined by means of dynamic tests (DT), such as resonant column test (RCT), or cyclic static test (CST), e.g. torsional shear (TST). The RC and TS tests are widely used laboratory methods to find stiffness of soil at small to medium strain range (0.0001–0.5%). The purpose of this paper is to present the experimental results from RC and CS laboratory tests on silty-sandy clay from the western part of Warsaw, Poland. The study aims to compare the shear modulus values obtained from two different research techniques. The influence of, in particular, the applied effective pressure, associated shear strain and experimental method (i.e. loading frequency and output amplitude) on the shear modulus at small strains (Gmax) and secant shear modulus (G) are investigated and proved. Generally, the results reveal that the examined soils stiffness calculated from TS tests is lower than from RC tests.

18

Boron retention in soil samples from apple orchards in Grojec and Sandomierz Regions

58%

Wojcik P.

Journal of Fruit and Ornamental Plant Research

|

1998

|

tom 06

|

nr 3-4

19

Denitrification, organic matter and redox potential transformations in Cambisols

58%

Wlodarczyk T., Stepniewska Z., Brzezinska M.

International Agrophysics

|

2003

|

tom 17

|

nr 4

20

Occurrence and germination of dinoflagellate cysts in surface sediments from the Red Sea off the coasts of Saudi Arabia

51%

Mohamed Z. A., Al-Shehri A. M.

Oceanologia

|

2011

|

tom 53

|

nr 1

The distribution and abundance of dinoflagellate cyst assemblages were investigated in surface sediments from south-western Red sea coasts of Saudi Arabia at six sites during March 2010. A total of 19 taxa of dinoflagellate cysts were identified from all sites. The sampling sites showed a similar cyst assemblage, but they differed in total cyst abundance (3 to 4083 cysts g−1 dry weight). Cyst abundance was strongly correlated with sediment characteristics, the highest numbers being recorded in sediments with large contents of organic carbon, silt and clay. Cyst assemblages were dominated by cysts of potentially toxic species, including Cochlodinium polykrikos, Prorocentrum minimum, Dinophysis acuminata, Alexandrium catenella and Scrippsiella trochoidea. Most cysts germinated successfully at different rates at 15 and 25◦C. This study suggests that surface sediments from all Saudi Red Sea coasts should be monitored for the presence of dinoflagellate cysts to give ample warning of the presence and abundance of toxic species in a given area.

Ograniczanie wyników

Mechanical dispersion of clay from soil into water: readily-dispersed and spontaneously-dispersed clay

Minimization of phenol by natural occurrence adsorbent

Nonlinear dynamic properties of silty clay from Warsaw area

Small strain stiffness in overconsolidated Pliocene clays

Boron adsorption in soil as influenced by pH and competing anions

Surface heterogeneity effects in water vapour adsorption on clay minerals

Ecological, clay-based building engineering

Determination of the heating pile numerical model parameters based on the laboratory strength tests of clay at low temperatures

Determination of undrained shear strength and constrained modulus from DMT for stiff overconsolidated clays

Undrained shear strength of the heavily consolidated clay

Measuring the energies of aggregate bonding in soils

Shrinkage properties of three clay materials at different temperatures

Effects of soil management on the dispersibility of clay in a sandy soil

Effect of non-homogeneity of Pliocene clays in the vicinity of Warsaw and their physical properties

Respiration of soil enriched with manure and mineral materials (methodical aspects)

The evaluation of pliocene clays consistency state with using of flat dilatometer tests

Dynamic and cyclic static loading behavior of silty-sandy clay at small and moderate strains

Boron retention in soil samples from apple orchards in Grojec and Sandomierz Regions

Denitrification, organic matter and redox potential transformations in Cambisols

Occurrence and germination of dinoflagellate cysts in surface sediments from the Red Sea off the coasts of Saudi Arabia