Andrzej Bieganowski - Academia.edu (original) (raw)

Papers by Andrzej Bieganowski

International Journal of Biological Macromolecules

International Journal of Biological Macromolecules, 2016

This is the first report on the physicochemical properties of chitin obtained from larvae and ima... more This is the first report on the physicochemical properties of chitin obtained from larvae and imagoes of black soldier flies (Hermetia illucens). Scanning electron microscopy revealed differences in surface morphologies of the two types of chitin. The crystalline index values of chitins from adult flies and larvae were 24.9% and 35%, respectively. This is a trait that differentiates these biopolymers from chitins extracted from other sources described so far. X-ray diffraction patterns and IR spectroscopy revealed that both types of samples of chitin were in an α crystalline form. Also, the results of elemental analysis, thermal stabilities and FTIR spectroscopy of the chitins from larvae and adults of H. illucens were similar, which points to a general similarity in their physicochemical structure.

Journal of Microbiological Methods, 2011

Electrokinetic potential (ζ, zeta potential) is one of the parameters which characterize the phys... more Electrokinetic potential (ζ, zeta potential) is one of the parameters which characterize the physicochemical properties of the bacterial cell envelope. The term is often used in the context of adhesiveness of bacteria and biofilm formation. This work presents the methodological aspects of zeta potential determination in strain Rt24.2 of Rhizobium leguminosarum using Laser Doppler Velocimetry combined with Phase Analysis Light Scattering and changed electric field techniques. The influence of media (0.9% NaCl, 0.2% NaCl, TY, GYM, 79CA, 20E and M1), temperature of measurement, number of measurement repetitions, phase of culture, concentration of bacteria, and storage at low temperature on the value of electrokinetic potential was investigated and a comparison was drawn between live and dead bacteria. All of those factors modified the zeta potential, showing that these parameters should be precisely specified in studies of bacterial electrokinetic potential, which is not always done. The obtained results also indicated that the zeta potential of Rhizobium leguminosarum should be determined directly in samples without storage at a defined bacterial density. The measurement should be done only once in a sample inserted into the cell of a measuring device to eliminate changes occurring in the sample (increase of electrolytic conductivity) under the electric field used.

The splashing of water drops on a soil surface is the first step of water erosion. There have bee... more The splashing of water drops on a soil surface is the first step of water erosion. There have been many investigations into splashing–most are based on recording and analysing images taken with high-speed cameras, or measuring the mass of the soil moved by splashing. Here, we present a new aspect of the splash phenomenon's characterization the measurement of the sound pressure level and the sound energy of the wave that propagates in the air. The measurements were carried out for 10 consecutive water drop impacts on the soil surface. Three soils were tested (Endogleyic Umbrisol, Fluvic Endogleyic Cambisol and Haplic Chernozem) with four initial moisture levels (pressure heads: 0.1 kPa, 1 kPa, 3.16 kPa and 16 kPa). We found that the values of the sound pressure and sound wave energy were dependent on the particle size distribution of the soil, less dependent on the initial pressure head, and practically the same for subsequent water drops (from the first to the tenth drop). The highest sound pressure level (and the greatest variability) was for Endo-gleyic Umbrisol, which had the highest sand fraction content. The sound pressure for this soil increased from 29 dB to 42 dB with the next incidence of drops falling on the sample The smallest (and the lowest variability) was for Fluvic Endogleyic Cambisol which had the highest clay fraction. For all experiments the sound pressure level ranged from ~27 to ~42 dB and the energy emitted in the form of sound waves was within the range of 0.14 μJ to 5.26 μJ. This was from 0.03 to 1.07% of the energy of the incident drops.

The adaptation of activated sludge from the Hajdow sewage treatment plant in a laboratory SBR was... more The adaptation of activated sludge from the Hajdow sewage treatment plant in a laboratory SBR was studied. The structure of the ciliate assembly was considered as a criterion. 32 ciliate species were found during the experiment. The composition and changes in the ciliate community structure during the process of activated sludge adaptation was examined. In the process of adaptation, reduction was observed in the number of ciliate species together with an increase in assembly total abundance. The decrease in the Shannon diversity index and equitability index in the adaptation process was observed. In the process of adaptation, two states of ciliate assembly were marked out -unstable transient period and stable period. During the transient period, reduction of ammonium utilization efficiency down to 50% and its subsequent increase up to 80% in the stable period were observed. In the transient period, the Simpson dominance index remained low but increased in the stable period. At a temperature of 10°C, the transient period lasted from six to nine days. After the stabilization process, the diversity of the ciliate assemblage remained at a lower level. Rarefaction methods showed that the number of potential ecological niches of ciliate amounted to 30 in the adaptation period, whereas there were only 15-20 ecological niches in adapted sludge.

Environmental Engineering Science, 2016

Sensors, 2014

A gas sensor array consisting of eight metal oxide semiconductor (MOS) type gas sensors was evalu... more A gas sensor array consisting of eight metal oxide semiconductor (MOS) type gas sensors was evaluated for its ability for assessment of the selected wastewater parameters. Municipal wastewater was collected in a wastewater treatment plant (WWTP) in a primary sedimentation tank and was treated in a laboratory-scale sequential batch reactor (SBR). A comparison of the gas sensor array (electronic nose) response to the standard physical-chemical parameters of treated wastewater was performed. To analyze the measurement results, artificial neural networks were used. E-nose-gas sensors array and artificial neural networks proved to be a suitable method for the monitoring of treated wastewater quality. Neural networks used for data validation showed high correlation between the electronic nose readouts and: (I) chemical oxygen demand (COD) (r = 0.988); (II) total suspended solids (TSS) (r = 0.938); (III) turbidity (r = 0.940); (IV) pH (r = 0.554); (V) nitrogen compounds: N-NO3 (r = 0.958), N-NO2 (r = 0.869) and N-NH3 (r = 0.978); (VI) and volatile organic compounds (VOC) (r = 0.987). Good correlation of the abovementioned parameters are observed under stable treatment conditions in a laboratory batch reactor.

The possibility of distinguishing different soil moisture levels by electronic nose (e-nose) was ... more The possibility of distinguishing different soil moisture levels by electronic nose (e-nose) was studied. Ten arable soils of various types were investigated. The measurements were performed for air-dry (AD) soils stored for one year, then moistened to field water capacity and finally dried within a period of 180 days. The volatile fingerprints changed during the course of drying. At the end of the drying cycle, the fingerprints were similar to those of the initial AD soils. Principal component analysis (PCA) and artificial neural network (ANN) analysis showed that e-nose results can be used to distinguish soil moisture. It was also shown that different soils can give different e-nose signals at the same moistures.

International Agrophysics, 2015

A b s t r a c t. This paper presents studies concerning the applicability of two clay materials f... more A b s t r a c t. This paper presents studies concerning the applicability of two clay materials for the construction of a sustainable landfill liner. The studies consisted in determination of basic characteristics of the materials, eg particle size distribution, bulk density, particle density, total porosity, pore size, mineralogy, specific surface area, nanoparticle size, and Atterberg limits, as well as measurements of their geotechnical and hydraulic parameters, such as in situ saturated hydraulic conductivity, modules of primary and secondary compression, cohesion, and angle of internal friction. Furthermore, the effects of compaction performed by the Proctor method at various water contents on swelling and shrinkage characteristics and saturated hydraulic conductivity were investigated in order to determine the compliance with the national requirements for selection of material for landfill liner construction. The determined characteristics and geotechnical parameters of the tested clay materials allowed qualifying them as suitable for municipal landfill construction. The shrinkage potential of the tested clays observed was rated as moderate to very high. The cyclic drying and rewetting of the clay materials performed resulted in a significant increase in saturated hydraulic conductivity. Thus, the clay sealing layers, as part of a multilayer liner, should be very carefully operated, preventing the drying out of the clay sealing and assuring the possibility of its constant saturation.

Sedimentary Geology, 2015

European Journal of Soil Biology, 2016

International Agrophysics, 2010

A b s t r a c t. The paper presents a comparison of particle size distributions of 23 mineral soi... more A b s t r a c t. The paper presents a comparison of particle size distributions of 23 mineral soils from SE Poland obtained by the laser diffraction and aerometric methods. There is good, statistically significant correlation between particle size distribution measured by aerometric and laser diffraction methods. The correlation is better when the results are compared for the same type of soil and for coarser fraction (sand).

International Agrophysics, 2013

International Agrophysics

A b s t r a c t. The authors propose a method for the elimination of dust particles from analysis... more A b s t r a c t. The authors propose a method for the elimination of dust particles from analysis of geometry of potato starch granules. The form and size differences between potato starch granules and dust particles permitted the application of suitable filters. The effectiveness of the method was verified through comparisons of particle size distributions of potato starch granules without dust particles and with deposited dust particles after the application of the algorithm/filter. At the same time, determination was made of the dynamics of dust deposition in the laboratory (ca. 4500particles cm -2 h -1). K e y w o r d s:

Soil Science Society of America Journal, 2015

ABSTRACT The particle-size distribution (PSD) is one of the most important soil characteristics u... more ABSTRACT The particle-size distribution (PSD) is one of the most important soil characteristics used in soil science. Numerous studies on the laser diffraction method (LDM) suggest that the PSD obtained by the LDM differs from that obtained by sieve sedimentation methods (SSMs). The aim of this study was to determine the potential causes of errors in PSD measurements using the LDM, especially in the context of conflicting reports regarding the over/underestimation of finer fractions in comparison with SSMs. Mixtures of two fractions of glass beads (15–50 and 1000–1180 μm) were measured with two differently constructed dispersion units (Hydro MU and Hydro G) and using two continuous phases (H2O, density 0.998 Mg m−3, and CsCl, density 1.582 Mg m−3). The error in the measurements using the LDM (the most extreme overestimation of the coarse fraction was approximately 275%) was attributed to insufficient homogenization of the soil suspension in the dispersion units. The degree of over- or underestimation depended on the ratio between the contents of each fraction. It is difficult to indicate clearly which dispersion unit construction was better in these investigations. The Hydro MU appeared to be slightly more suitable when the content of the given fractions features a wider range in relation to the content of the other fractions. However, Hydro G may be better suited to soils with relatively fewer sand fraction particles. The knowledge of the causes of the errors should help to minimize errors in PSD measurements by the LDM and lead to better interpretations of the results.

Journal of Plant Nutrition and Soil Science, 2014

ABSTRACT Particle size distribution (PSD) is a major soil characteristic, which is essential and ... more ABSTRACT Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve-hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM-measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM-measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve-hydrometer counterparts.

Ecological Chemistry and Engineering S, 2012

The paper presents a study on the possibility of using the laser diffraction method for measuring... more The paper presents a study on the possibility of using the laser diffraction method for measuring the size of the activated sludge particles. Susceptibility of the particles to mechanical disintegration, dependent on the programmed value of stirring intensity, was observed (stirring was caused by required dynamic flow of analysed suspension through the measurement unit). According to the conclusions presented in this paper, it may be assumed that the laser diffraction method can be applied for measurement of activated sludge particle diameters under the following conditions: 1) the size of activated sludge particles measured by the laser diffraction method is not a real value, but after standardisation of measurement conditions can be treated as a parameter describing the sludge; 2) the particle diameters of activated sludge should be stabilised before the measurement, eg by mixing in the measurement unit or by ultrasound waves application.

PLOS ONE, 2015

One of the methods for testing splash (the first phase of water erosion) may be an analysis of ph... more One of the methods for testing splash (the first phase of water erosion) may be an analysis of photos taken using so-called high-speed cameras. The aim of this study was to determine the reproducibility of measurements using a single drop splash of simulated precipitation. The height from which the drops fell resulted in a splash of 1.5 m. Tests were carried out using two types of soil: Eutric Cambisol (loamy silt) and Orthic Luvisol (sandy loam); three initial pressure heads were applied equal to 16 kPa, 3.1 kPa, and 0.1 kPa. Images for one, five, and 10 drops were recorded at a rate of 2000 frames per second. It was found that (i) the dispersion of soil caused by the striking of the 1st drop was significantly different from the splash impact caused by subsequent drops; (ii) with every drop, the splash phenomenon proceeded more reproducibly, that is, the number of particles of soil and/or water that splashed were increasingly close to each other; (iii) the number of particles that were detached during the splash were strongly correlated with its surface area; and (iv) the higher the water film was on the surface the smaller the width of the crown was.

International Agrophysics, 2012

A b s t r a c t. The comparison of particle size distributions measured by sedimentation methods ... more A b s t r a c t. The comparison of particle size distributions measured by sedimentation methods and laser diffraction shows the underestimation of the fine (clay) fraction. This is attributed mainly to the shape of clay particles being different than spherical. The objective of this study was to demonstrate differences in the results of particle size distributions of soils determined with the method of laser diffraction using two different dispersion units of the Malvern Mastersizer 2000.

Plant and Soil, 2014

Background and aims The acidic exopolysaccharide (EPS) produced by Rhizobium leguminosarum bv. tr... more Background and aims The acidic exopolysaccharide (EPS) produced by Rhizobium leguminosarum bv. trifolii is required for the establishment of effective symbiosis with compatible host plants (Trifolium spp.). In the rhizobium-legume interaction, early stages of root infection and nodule development have been well studied from a genetic standpoint. However, factors important for colonization of several surfaces by rhizobia, Plant Soil

International Journal of Biological Macromolecules

International Journal of Biological Macromolecules, 2016

This is the first report on the physicochemical properties of chitin obtained from larvae and ima... more This is the first report on the physicochemical properties of chitin obtained from larvae and imagoes of black soldier flies (Hermetia illucens). Scanning electron microscopy revealed differences in surface morphologies of the two types of chitin. The crystalline index values of chitins from adult flies and larvae were 24.9% and 35%, respectively. This is a trait that differentiates these biopolymers from chitins extracted from other sources described so far. X-ray diffraction patterns and IR spectroscopy revealed that both types of samples of chitin were in an α crystalline form. Also, the results of elemental analysis, thermal stabilities and FTIR spectroscopy of the chitins from larvae and adults of H. illucens were similar, which points to a general similarity in their physicochemical structure.

Journal of Microbiological Methods, 2011

Electrokinetic potential (ζ, zeta potential) is one of the parameters which characterize the phys... more Electrokinetic potential (ζ, zeta potential) is one of the parameters which characterize the physicochemical properties of the bacterial cell envelope. The term is often used in the context of adhesiveness of bacteria and biofilm formation. This work presents the methodological aspects of zeta potential determination in strain Rt24.2 of Rhizobium leguminosarum using Laser Doppler Velocimetry combined with Phase Analysis Light Scattering and changed electric field techniques. The influence of media (0.9% NaCl, 0.2% NaCl, TY, GYM, 79CA, 20E and M1), temperature of measurement, number of measurement repetitions, phase of culture, concentration of bacteria, and storage at low temperature on the value of electrokinetic potential was investigated and a comparison was drawn between live and dead bacteria. All of those factors modified the zeta potential, showing that these parameters should be precisely specified in studies of bacterial electrokinetic potential, which is not always done. The obtained results also indicated that the zeta potential of Rhizobium leguminosarum should be determined directly in samples without storage at a defined bacterial density. The measurement should be done only once in a sample inserted into the cell of a measuring device to eliminate changes occurring in the sample (increase of electrolytic conductivity) under the electric field used.

The splashing of water drops on a soil surface is the first step of water erosion. There have bee... more The splashing of water drops on a soil surface is the first step of water erosion. There have been many investigations into splashing–most are based on recording and analysing images taken with high-speed cameras, or measuring the mass of the soil moved by splashing. Here, we present a new aspect of the splash phenomenon's characterization the measurement of the sound pressure level and the sound energy of the wave that propagates in the air. The measurements were carried out for 10 consecutive water drop impacts on the soil surface. Three soils were tested (Endogleyic Umbrisol, Fluvic Endogleyic Cambisol and Haplic Chernozem) with four initial moisture levels (pressure heads: 0.1 kPa, 1 kPa, 3.16 kPa and 16 kPa). We found that the values of the sound pressure and sound wave energy were dependent on the particle size distribution of the soil, less dependent on the initial pressure head, and practically the same for subsequent water drops (from the first to the tenth drop). The highest sound pressure level (and the greatest variability) was for Endo-gleyic Umbrisol, which had the highest sand fraction content. The sound pressure for this soil increased from 29 dB to 42 dB with the next incidence of drops falling on the sample The smallest (and the lowest variability) was for Fluvic Endogleyic Cambisol which had the highest clay fraction. For all experiments the sound pressure level ranged from ~27 to ~42 dB and the energy emitted in the form of sound waves was within the range of 0.14 μJ to 5.26 μJ. This was from 0.03 to 1.07% of the energy of the incident drops.

The adaptation of activated sludge from the Hajdow sewage treatment plant in a laboratory SBR was... more The adaptation of activated sludge from the Hajdow sewage treatment plant in a laboratory SBR was studied. The structure of the ciliate assembly was considered as a criterion. 32 ciliate species were found during the experiment. The composition and changes in the ciliate community structure during the process of activated sludge adaptation was examined. In the process of adaptation, reduction was observed in the number of ciliate species together with an increase in assembly total abundance. The decrease in the Shannon diversity index and equitability index in the adaptation process was observed. In the process of adaptation, two states of ciliate assembly were marked out -unstable transient period and stable period. During the transient period, reduction of ammonium utilization efficiency down to 50% and its subsequent increase up to 80% in the stable period were observed. In the transient period, the Simpson dominance index remained low but increased in the stable period. At a temperature of 10°C, the transient period lasted from six to nine days. After the stabilization process, the diversity of the ciliate assemblage remained at a lower level. Rarefaction methods showed that the number of potential ecological niches of ciliate amounted to 30 in the adaptation period, whereas there were only 15-20 ecological niches in adapted sludge.

Environmental Engineering Science, 2016

Sensors, 2014

A gas sensor array consisting of eight metal oxide semiconductor (MOS) type gas sensors was evalu... more A gas sensor array consisting of eight metal oxide semiconductor (MOS) type gas sensors was evaluated for its ability for assessment of the selected wastewater parameters. Municipal wastewater was collected in a wastewater treatment plant (WWTP) in a primary sedimentation tank and was treated in a laboratory-scale sequential batch reactor (SBR). A comparison of the gas sensor array (electronic nose) response to the standard physical-chemical parameters of treated wastewater was performed. To analyze the measurement results, artificial neural networks were used. E-nose-gas sensors array and artificial neural networks proved to be a suitable method for the monitoring of treated wastewater quality. Neural networks used for data validation showed high correlation between the electronic nose readouts and: (I) chemical oxygen demand (COD) (r = 0.988); (II) total suspended solids (TSS) (r = 0.938); (III) turbidity (r = 0.940); (IV) pH (r = 0.554); (V) nitrogen compounds: N-NO3 (r = 0.958), N-NO2 (r = 0.869) and N-NH3 (r = 0.978); (VI) and volatile organic compounds (VOC) (r = 0.987). Good correlation of the abovementioned parameters are observed under stable treatment conditions in a laboratory batch reactor.

The possibility of distinguishing different soil moisture levels by electronic nose (e-nose) was ... more The possibility of distinguishing different soil moisture levels by electronic nose (e-nose) was studied. Ten arable soils of various types were investigated. The measurements were performed for air-dry (AD) soils stored for one year, then moistened to field water capacity and finally dried within a period of 180 days. The volatile fingerprints changed during the course of drying. At the end of the drying cycle, the fingerprints were similar to those of the initial AD soils. Principal component analysis (PCA) and artificial neural network (ANN) analysis showed that e-nose results can be used to distinguish soil moisture. It was also shown that different soils can give different e-nose signals at the same moistures.

International Agrophysics, 2015

A b s t r a c t. This paper presents studies concerning the applicability of two clay materials f... more A b s t r a c t. This paper presents studies concerning the applicability of two clay materials for the construction of a sustainable landfill liner. The studies consisted in determination of basic characteristics of the materials, eg particle size distribution, bulk density, particle density, total porosity, pore size, mineralogy, specific surface area, nanoparticle size, and Atterberg limits, as well as measurements of their geotechnical and hydraulic parameters, such as in situ saturated hydraulic conductivity, modules of primary and secondary compression, cohesion, and angle of internal friction. Furthermore, the effects of compaction performed by the Proctor method at various water contents on swelling and shrinkage characteristics and saturated hydraulic conductivity were investigated in order to determine the compliance with the national requirements for selection of material for landfill liner construction. The determined characteristics and geotechnical parameters of the tested clay materials allowed qualifying them as suitable for municipal landfill construction. The shrinkage potential of the tested clays observed was rated as moderate to very high. The cyclic drying and rewetting of the clay materials performed resulted in a significant increase in saturated hydraulic conductivity. Thus, the clay sealing layers, as part of a multilayer liner, should be very carefully operated, preventing the drying out of the clay sealing and assuring the possibility of its constant saturation.

Sedimentary Geology, 2015

European Journal of Soil Biology, 2016

International Agrophysics, 2010

A b s t r a c t. The paper presents a comparison of particle size distributions of 23 mineral soi... more A b s t r a c t. The paper presents a comparison of particle size distributions of 23 mineral soils from SE Poland obtained by the laser diffraction and aerometric methods. There is good, statistically significant correlation between particle size distribution measured by aerometric and laser diffraction methods. The correlation is better when the results are compared for the same type of soil and for coarser fraction (sand).

International Agrophysics, 2013

International Agrophysics

A b s t r a c t. The authors propose a method for the elimination of dust particles from analysis... more A b s t r a c t. The authors propose a method for the elimination of dust particles from analysis of geometry of potato starch granules. The form and size differences between potato starch granules and dust particles permitted the application of suitable filters. The effectiveness of the method was verified through comparisons of particle size distributions of potato starch granules without dust particles and with deposited dust particles after the application of the algorithm/filter. At the same time, determination was made of the dynamics of dust deposition in the laboratory (ca. 4500particles cm -2 h -1). K e y w o r d s:

Soil Science Society of America Journal, 2015

ABSTRACT The particle-size distribution (PSD) is one of the most important soil characteristics u... more ABSTRACT The particle-size distribution (PSD) is one of the most important soil characteristics used in soil science. Numerous studies on the laser diffraction method (LDM) suggest that the PSD obtained by the LDM differs from that obtained by sieve sedimentation methods (SSMs). The aim of this study was to determine the potential causes of errors in PSD measurements using the LDM, especially in the context of conflicting reports regarding the over/underestimation of finer fractions in comparison with SSMs. Mixtures of two fractions of glass beads (15–50 and 1000–1180 μm) were measured with two differently constructed dispersion units (Hydro MU and Hydro G) and using two continuous phases (H2O, density 0.998 Mg m−3, and CsCl, density 1.582 Mg m−3). The error in the measurements using the LDM (the most extreme overestimation of the coarse fraction was approximately 275%) was attributed to insufficient homogenization of the soil suspension in the dispersion units. The degree of over- or underestimation depended on the ratio between the contents of each fraction. It is difficult to indicate clearly which dispersion unit construction was better in these investigations. The Hydro MU appeared to be slightly more suitable when the content of the given fractions features a wider range in relation to the content of the other fractions. However, Hydro G may be better suited to soils with relatively fewer sand fraction particles. The knowledge of the causes of the errors should help to minimize errors in PSD measurements by the LDM and lead to better interpretations of the results.

Journal of Plant Nutrition and Soil Science, 2014

ABSTRACT Particle size distribution (PSD) is a major soil characteristic, which is essential and ... more ABSTRACT Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve-hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM-measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM-measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve-hydrometer counterparts.

Ecological Chemistry and Engineering S, 2012

The paper presents a study on the possibility of using the laser diffraction method for measuring... more The paper presents a study on the possibility of using the laser diffraction method for measuring the size of the activated sludge particles. Susceptibility of the particles to mechanical disintegration, dependent on the programmed value of stirring intensity, was observed (stirring was caused by required dynamic flow of analysed suspension through the measurement unit). According to the conclusions presented in this paper, it may be assumed that the laser diffraction method can be applied for measurement of activated sludge particle diameters under the following conditions: 1) the size of activated sludge particles measured by the laser diffraction method is not a real value, but after standardisation of measurement conditions can be treated as a parameter describing the sludge; 2) the particle diameters of activated sludge should be stabilised before the measurement, eg by mixing in the measurement unit or by ultrasound waves application.

PLOS ONE, 2015

One of the methods for testing splash (the first phase of water erosion) may be an analysis of ph... more One of the methods for testing splash (the first phase of water erosion) may be an analysis of photos taken using so-called high-speed cameras. The aim of this study was to determine the reproducibility of measurements using a single drop splash of simulated precipitation. The height from which the drops fell resulted in a splash of 1.5 m. Tests were carried out using two types of soil: Eutric Cambisol (loamy silt) and Orthic Luvisol (sandy loam); three initial pressure heads were applied equal to 16 kPa, 3.1 kPa, and 0.1 kPa. Images for one, five, and 10 drops were recorded at a rate of 2000 frames per second. It was found that (i) the dispersion of soil caused by the striking of the 1st drop was significantly different from the splash impact caused by subsequent drops; (ii) with every drop, the splash phenomenon proceeded more reproducibly, that is, the number of particles of soil and/or water that splashed were increasingly close to each other; (iii) the number of particles that were detached during the splash were strongly correlated with its surface area; and (iv) the higher the water film was on the surface the smaller the width of the crown was.

International Agrophysics, 2012

A b s t r a c t. The comparison of particle size distributions measured by sedimentation methods ... more A b s t r a c t. The comparison of particle size distributions measured by sedimentation methods and laser diffraction shows the underestimation of the fine (clay) fraction. This is attributed mainly to the shape of clay particles being different than spherical. The objective of this study was to demonstrate differences in the results of particle size distributions of soils determined with the method of laser diffraction using two different dispersion units of the Malvern Mastersizer 2000.

Plant and Soil, 2014

Background and aims The acidic exopolysaccharide (EPS) produced by Rhizobium leguminosarum bv. tr... more Background and aims The acidic exopolysaccharide (EPS) produced by Rhizobium leguminosarum bv. trifolii is required for the establishment of effective symbiosis with compatible host plants (Trifolium spp.). In the rhizobium-legume interaction, early stages of root infection and nodule development have been well studied from a genetic standpoint. However, factors important for colonization of several surfaces by rhizobia, Plant Soil