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Laboratory assessment of permeability of a groundwater protective barrier

100%

Lipinski M. J., Koda E., Wdowska M. K.

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

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2007

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nr 38

69-79

Laboratory assessment of permeability of a groundwater protective barrier. The paper presents results of laboratory assessment of permeability of cement-bentonite self hardening mixtures which have recently been the most often used for construction of cut–off walls mitigating hazard of sanitary landfi lls. Laboratory tests were carried out on reconstituted and natural (undisturbed) material of the barrier. Due to the fact that actual permeability characteristics of reconstituted material are time and density dependent, changes of permeability are described against those variables. Comparison of these data with test results obtained for undisturbed material help to understand the process of changing properties of the barrier in the environment.

2

Vertical and horizontal permeability measurements in organic soils

88%

Malinowska E. E., Szymanski A.

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

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2015

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tom 47

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nr 2

The paper is referring to vertical and horizontal laboratory permeability measurements in soft organic soils. The estimation of anisotropic permeability in soft organic soils, as peats, requires to use a special apparatus and the knowledge of proper analysis of the test results. During loading the void ratio decreases substantially that causes the changeability of the permeability. The change of permeability during the compression is very important because of the infl uence of the consolidation coefficient. Initial strain in soft organic soils appears very quickly, just after loading, and brings immediately the decrease of permeability. In most of the estimations, it is assumed that during the consolidation process the water flows just in the vertical direction. In soft organic soils, like peats, the consolidation theory should consider the changes of mechanical and physical properties in consolidation period, in both directions. The direct measurement of vertical and horizontal permeability of organic soil and the non-Darcian flow theory may be of considerable importance in estimating pore water pressure dissipation, and settlement rates in the consolidation model. In the paper, the method of investigation and the test results of the vertical and horizontal permeability are presented. The Modifi ed Rowe Cell Set for obtaining consolidation and fl ow characteristics in different directions is used.

3

Laboratory assessment of permeability of sand and biopolymer mixtures

88%

Wiszniewski M., Skutnik Z., Cabalar A. F.

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

This research presents a method of creating seepage barriers in a sandy soil using biopolymer additives (biosubstance), which consist of polysaccharides and water. Polysaccharides strongly interact with water to produce a viscous suspension. The paper aims to investigate the infl uence of a biosubstance employed in a highly permeable sandy soil. Amount of the biopolymer used in a sample were 0.5, 1.0 and 1.5%, by dry weight. The test results indicate that the hydraulic conductivity signifi cantly decrease with the amount of biosubstance added but only slightly increase when curing time gets longer. It is thought that such application, which is a relatively new soil improvement technique, could be used as a seepage barrier installation required to protect some geotechnical works including foundation, underground structures and waste disposals.

4

Colour, mechanical properties and water vapour permeability of pectin films

75%

Galus S., Uchanski P., Lenart A.

Acta Agrophysica

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2013

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tom 20

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nr 3

The aim of this work was to analyse the effect of pectin and glycerol concentration on colour, mechanical properties and water vapour permeability of pectin edible films. Pectin films were obtained from apple pectin film-forming solutions at concentrations of 1.5, 2.5 and 3.5%. Glycerol was added as a plasticizer at 30, 50 and 70% (w/w of pectin). Colour was measured in the L*a*b* system and total colour difference was calculated. Water vapour permeability at relative humidity differentials of 30-100% was measured at 25°C. Mechanical properties were presented as tensile force and elongation at break. Based on the results obtained, increasing content of pectin caused an increase in total colour difference, water vapour permeability and tensile force of ana-lysed films. Glycerol caused increasing elongation at break and water vapour permeability.

5

Comparative non-linear regression - case of infiltration rate increase from upstream in valley

75%

Keita A., Yacouba H., Hayde L. G., Schultz B.

International Agrophysics

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2014

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tom 28

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nr 3

In Tropical Savannah flooded valley soils, very low infiltration rates often result in acidic conditions favourable to high concentrations of metallic ions, toxic for rice. Determination of the under-phreatic infiltration rate is important in drainage design to reclaim degraded soils. Several studies have addressed the mapping of the infiltration rate. Yet, its relationship with the toposequence of the valley is not clarified. This paper has investi- gated such a possibility, examining the case of the irrigated rice valley of Tiefora, Burkina Faso. Nine boreholes – from 1 to 5 m deep – were implemented from upstream to downstream. The Lefranc permeability test of the under-phreatic level in water- logged soils – used when the impervious layer is close to soil sur- face or absent – was conducted. First, a comparative regression was applied to the data, including all the parameters of the regression curves. In the case of dissimilarity of the infiltration processes, the comparison focused on the final permeability. The results show a permeability increase from upstream (0.10±0.10 cm h -1 ) to down- stream (greater than 20±10 cm h -1 in some places). Taking into account such a permeability increase in the subsurface drainage system design would result in implementation of more efficient and cost effective systems.

6

Effect of iron supplementation on intestinal function and oxidative stress in piglets with induced colitis

75%

Chen Q., Le G. W., Shi Y. H., Zhang S. M., Jin X.

Journal of Animal and Feed Sciences

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2007

|

tom 16

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nr 2

205-213

7

Effect of biofilm formation by Pseudomonas aeruginosa on gas permeability of food wrapping foils

75%

Boguslawska-Was E., Lisiecki S., Drozdowska A., Ilczuk K.

Polish Journal of Food and Nutrition Sciences

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2007

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tom 57

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nr 2

167-172

The natural precedence of microorganisms growth on the damp surfaces is the formation of biofilm. The arising biolayer, stabilized by extracellular substances, is becoming hard to remove biological structure, the enzymatic activity of which can lead to violation of the packaging, and consequently to acceleration of the process of food spoilage. The microorganisms of Pseudomonas species are widely spread in food products’ environment. In order to perform the analysis three types of food wrapping foils from polyamide – polyethylene (PA/PE), which were kept in Pseudomonas culture, were used in the study. Two strains were used – the standard ATCC 15442 (WZ) and the strain isolated from pork-beef minced meat (MB) airtight packaged. All cultures were run at the temperatures 4°C and 20°C. It was reported that on all types of food wrapping foils biofilms were developed, which were formed by Ps. aeruginosa. The biolayers developed decreased permeability of foils, which was shown by restriction of permeability for gases. The changes of foils properties analysed here were most of all dependent on the type of the foil.

8

Clayey sand–nonwoven geotextile interface characterisation through gradient ratio test

75%

Markiewicz A.

Acta Scientiarum Polonorum. Architectura

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2022

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tom 21

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nr 1

9

Hydraulic performance of zero-valent iron and nano-sized zero-valent iron permeable reactive barriers-laboratory test

75%

Fronczyk J., Pawluk K.

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

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2014

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tom 46

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nr 1

The hydraulic conductivity of zero-valent iron treatment zone of permeable reactive barriers (PRBs) may be decreased by reducing the porosity caused by gas production and solids precipitation. The study was undertaken in order to evaluate the influence of chloride and heavy metals on the hydraulic conductivity of ZVI and nZVI using hydraulic conductivity tests as well as continuous column tests. Results show that the lead retention in the solution had no impact for hydraulic conductivity in ZVI sample, on the other hand the calculated hydraulic conductivity losses in nZVI sample (from 4.10·10–5 to 2.30·10–5 m·s–1) were observed. Results also indicate that liquids containing the mixture of heavy metals may cause signifi cant decrease in hydraulic conductivity (from 1.03·10–4 to 1.51·10–6 m·s–1). During the column tests, several number of clogging of the reactive material caused by iron hydroxides precipitation was observed over the course of injection of heavy metals solution. In contrast, the hydraulic conductivity of ZVI and nZVI is unaffected when they are permeated with chloride ions solution (k = 1.03·10–4 m·s–1). Finally, the results indicate the need to take account of changes in the hydraulic conductivity of reactive materials for successful implementation of PRBs technology.

10

Permeability of ethene and propene through PMSP and polysulfone [PSF]

75%

Popescu R., Sdrula N.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

11

The composition of cell wall skeleton and outermost lipids of Mycobacterium vaccae is modified by ethambutol treatment

75%

Rumijowska-Galewicz A., Korycka-Machala M., Lisowska K., Dziadek J.

Polish Journal of Microbiology

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2008

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tom 57

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nr 2

Ethambutol (EMB) is a first line drug in tuberculosis treatment inhibiting the biosynthesis of arabinogalactan, which is a component of the mycobacterial cell wall. The growth of Mycobacterium vaccae cells in the presence of EMB increases cell wall permeability, which was monitored by β-sitosterol biotransformation. GC/MS and GLC/MS (gas chromatography/mass spectrometry) analysis revealed dramatic changes in the content of covalently bound mycolic acids and in molar ratio galactose (Gal) to arabinose (Ara) in the cell envelopes of EMB-treated cells. The detected variations in the compositions of fatty acids indicate that both the cell wall skeleton and outer layer (free lipids) are decomposed due to EMB treatment.

12

The effect of ethambutol on mycobacterial cell wall permeability to hydrophobic compounds

75%

Korycka-Machala M., Rumijowska-Galewicz A., Dziadek J.

Polish Journal of Microbiology

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2005

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tom 54

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nr 1

Ethambutol (EMB), the first line drug in the treatment of tuberculosis, is an inhibitor of the biosynthesis of the cell wall compound - arabinogalactan. It was found that EMB at sub-inhibitory concentration increases the permeability of the M. vaccae cell wall, which was monitored by cell sensitization to erythromycin and rifampicin. The high permeability of the cell wall to hydrophobic compounds allows enhanced intracellular bioconversion of (β -sitosterol to 4-androsten-3,17-dione (AD) and l,4-androstadien-3,17-dione (ADD).

13

Influence of the corticotropin releasing hormone (CRH) on the brain-blood barrier permeability in cerebral ischemia in rats

75%

Hendryk S., Jedrzejowska-Szypulka H., Josko J., Jarzab B., Dohler K. D.

Journal of Physiology and Pharmacology

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2002

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tom 53

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nr 1

The increase in the blood-brain barrier (BBB)permeability and a developing cerebral oedema due to the ischemic infarction appear a few hours,and intensify during a few days,after closing the carotid arteries.It fails to be clear,however,what causes the increase in the microvessels damage,and whether the damage is a secondary result of the vasoactive substances released by the neurones and glia cells damaged by the ischemia.CRH,which plays an essential role in integrative the nervous,endocrine, and immunological systems,has a positive effect on the decrease in the permeability of the BBB damaged by various physical and chemical factors.Therefore,the examination of the CRH role in the cerebral ischemia may prove useful for explaining the processes taking place in the foci of the cerebral infarction and their environment. The experiment was carried out on rats which,20 minutes before closing of both internal carotid arteries,was administered 10 µg CRH to cerebrospinal fluid via cisterna magna of the brain.The BBB permeability was measured 30 minutes,3 hours,3 days,and 7 days after closing the arteries.The experiment has shown the CRH protective effect on the BBB and its consequent effect on the decrease in the BBB permeability which appears in the 3 hours after closing the arteries (p<0.05),and is high significant during the chronic phase of the cerebral ischemia (p<0.03).It can be thus concluded that CRH,by affecting directly the endothelium of the cerebral vessels, decreases the endothelial damage in the acute phase of the ischemia.The decrease is noted to be more significant in the chronic phase of the ischemia;such an effect can be attributed to CRH stimulating the hypothalamic-adrenal axis,and to the secondary activation of the mechanisms decreasing the BBB permeability.

14

Investigation of enzymatic effects on pit membranes using light and scanning electron microscopy

63%

Durmaz S., Yildiz U. C., Ozturk M., Serdar B.

Drewno. Prace Naukowe. Doniesienia. Komunikaty

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2016

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tom 59

|

nr 198

15

Quality parameters determining the conditions of sea transportation of copper sulphide concentrates

63%

Popek M.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2015

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nr 3

16

A mathematical approach for assessing the transport of large neutral amino acids across the blood-brain barrier in man

63%

Dahl R. H., Berg R. M. G.

Acta Neurobiologiae Experimentalis

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2015

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tom 75

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nr 4

Changes in the large neutral amino acid (LNAA) transport across the blood-brain barrier (BBB) is thought to contribute to brain dysfunction in a number of clinical conditions, including phenylketonuria, acute liver failure, and sepsis. Here, we present a novel approach for estimating BBB permeability and the LNAA concentrations in brain extracellular fluid, by demonstrating that they can be mathematically derived on the basis of kinetic constants of the BBB available from the literature, if cerebral blood flow and the arterial and jugular venous LNAA concentrations are known. While it is well known that the permeability surface area product of the BBB to a LNAA from blood to brain (PS1) can be calculated from the arterial LNAA concentrations and kinetic constants of the BBB, we demonstrate that the permeability surface area product from brain to blood (PS2) can be calculated by deriving the substrate activity of the saturable transporter from the kinetic constants and arterial and jugular venous LNAA concentrations, and that the concentration of the LNAA in brain extracellular fluid can then be determined. This approach is methodically simple, and may be useful for assessing the transcerebral exchange kinetics of LNAAs in future human-experimental and clinical studies.

17

Evaluation of water vapor permeability of biodegradable starch-based films

63%

Rejak A., Wojtowicz A., Oniszczuk T., Niemczuk D., Nowacka M.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2014

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tom 14

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nr 3

18

The influence of selenium compounds on the permeability of wheat callus cell plasma membranes in the presence of cadmium ions

63%

Wrona M., Sieprawska A., Tejchman W., Filek M.

Acta Physiologiae Plantarum

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2007

|

tom 29

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nr 1 Suppl.

19

The effects of intestinal nematode L4 stage on mouse experimental autoimmune encephalomyelitis

63%

Donskow-Lysoniewska K., Krawczak K., Bocian K., Doligalska M.

Archivum Immunologiae et Therapiae Experimentalis

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2018

|

tom 66

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nr 3

20

Applications of permeability, oedometer and direct shear tests to the sand mixed with waste tire crumb

63%

Wiszniewski M., Cabalar A. F.

Acta Scientiarum Polonorum. Architectura

|

2016

|

tom 15

|

nr 1

The amount of the used waste rubbers in the world has been increasing every year, and their utilization, become a major environmental problem worldwide. The present experimental work has been performed to investigate the influence of rubber inclusion on the behavior of a sand. Geotechnical properties of the sand, and sand with tire crumb at various ratios mixtures (0, 2.5, 7.5, and 15%) were investigated through a series of mechanical tests, which are sieving, permeability, direct shear and consolidation. From the results of conducted tests, it is revealed that the addition of tire crumb grains increased both the permeability and the compressional characteristics of the sand. Besides, in this work, inter-granular void ratio (es) was employed as an alternative parameter to express the compressive response of sand-tire crumb mixtures. It is seen that intergranular void ratio concept is a good indicator for understanding the behavior of sands with waste tire crumb.

Ograniczanie wyników

Laboratory assessment of permeability of a groundwater protective barrier

Vertical and horizontal permeability measurements in organic soils

Laboratory assessment of permeability of sand and biopolymer mixtures

Colour, mechanical properties and water vapour permeability of pectin films

Comparative non-linear regression - case of infiltration rate increase from upstream in valley