Wyniki wyszukiwania

1

Effects of anisotropy in magnetotelluric soundings

100%

Miecznik J., Klitynski W.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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1992

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tom 40

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nr 4

2

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Possible means of overcoming sedimentation by motile sea-picoplankton cells

75%

Pundyak O.

Oceanologia

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2017

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tom 59

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nr 2

A model for overcoming the gravity by sea-picoplankton cells is proposed here. It is based on different means of escaping from potential predators used by cells of co-existing picoplankton species. These different means cause friction anisotropy of motile cells with strong antipredator behavior (AB). According to equations of stochastic movement used in this model for picoplankton cells with strong AB, collocated with high concentration of cells with weak or absent AB, the sedimentation can be considerably overcome.

3

Strengthening of veneers for 3D-forming

75%

Zemiar J., Fekiac J., Gaborik J.

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

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2014

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tom 88

Strengthening of veneers for 3D-forming. 3D - forming of veneers is used only in limited extent. The reasons are wood properties, mainly anisotropy of wood. In this paper, we propose some chosen methods for strengthening of veneers in directions parallel and perpendicular to the grains, with strengthening means such as hotmelt adhesive and glass fibre with adhesive coating. Properties of modified veneers were compared with the properties of reference - untreated veneers. We compared these properties: strength and deformations - extension in tension, strength and deflection in bending, and 3D - formability. From the results, we can conclude that referred treatments resulted in a slight improvement of 3D - formability.

4

Surface anisotropy orients cell divisions in contact guided cells

75%

Krzysiek-Maczka G., Korohoda W.

Folia Biologica

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2008

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tom 56

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nr 1-2

13-19

5

Young modulus of face layer and core layer in three directions on the example of P2 particleboard

75%

Archanowicz P., Beer P.

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

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2012

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tom 77

Young modulus of face layer and core layer in three directions on the example of P2 particleboard. The Young's modulus is main parameter characterizing particleboard material which was tested during the bending test according to EN 310. It also known as flexural modulus or modulus of elasticity. For industrial and comparative usage that bending test is sufficient. However, for the purpose of numerical analysis one material constant is not sufficient to describe the material at an acceptable level. The density is undoubtedly related to the mechanical properties of particleboard. The aim of this research is to determine Young modulus of the core layer and the face of particleboard in three directions on the example of chipboard type P2.

6

Gemini ester quat surfactants and their biological activity

63%

Luczynski J., Frackowiak R., Wloch A., Kleszczynska H., Witek S.

Cellular and Molecular Biology Letters

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2013

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tom 18

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nr 1

Cationic gemini surfactants are an important class of surface-active compounds that exhibit much higher surface activity than their monomeric counterparts. This type of compound architecture lends itself to the compound being easily adsorbed at interfaces and interacting with the cellular membranes of microorganisms. Conventional cationic surfactants have high chemical stability but poor chemical and biological degradability. One of the main approaches to the design of readily biodegradable and environmentally friendly surfactants involves inserting a bond with limited stability into the surfactant molecule to give a cleavable surfactant. The best-known example of such a compound is the family of ester quats, which are cationic surfactants with a labile ester bond inserted into the molecule. As part of this study, a series of gemini ester quat surfactants were synthesized and assayed for their biological activity. Their hemolytic activity and changes in the fluidity and packing order of the lipid polar heads were used as the measures of their biological activity. A clear correlation between the hemolytic activity of the tested compounds and their alkyl chain length was established. It was found that the compounds with a long hydrocarbon chain showed higher activity. Moreover, the compounds with greater spacing between their alkyl chains were more active. This proves that they incorporate more easily into the lipid bilayer of the erythrocyte membrane and affect its properties to a greater extent. A better understanding of the process of cell lysis by surfactants and of their biological activity may assist in developing surfactants with enhanced selectivity and in widening their range of application.

7

Stress distribution in cell wall – inferring stress anisotropy from the pattern of buckling in the innermost cell wall layer

63%

Borowska-Wykret D.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 3

8

The anisotrophic nature of the strain of biodegradable film produced from TPS starch

63%

Gladyszewska B., Ciupak A., Chocyk D., Moscicki L., Rejak A., Oniszczuk T.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2012

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tom 12

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nr 2

9

Analiz pokazatelja strukturno-mekhanicheskojj neodnorodnosti drevesiny

63%

Malakhova O., Lakida J.

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

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2012

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tom 78

10

Stress concentration around a circular opening in a wooden plate subjected to twisting moments

63%

Bodnar F., Jablonski M.

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

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2012

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tom 77

Stress concentration around a circular opening in a wooden plate subjected to twisting moments. The analytical solution of bending and twisting moment and of the stress concentration factors around the circular opening boundary in wooden plate modelled as orthotropic linear elastic material is presented here. The orthotropic plate with the circular opening is subjected to loading by twisting moment in all sides. The aim is to know the influence of the circular hole on concentration of stresses. Realised computations of the normal and shear moment and also of the stresses on the opening boundary are based on the linear theory of elasticity of anisotropic bodies with using of a complex variable method.

11

Anisotropy of mechanical properties of particleboard and medium density fibreboard in bending

63%

Wilczynski M., Tydryszewski K., Kociszewski M.

Roczniki Akademii Rolniczej w Poznaniu. Technologia Drewna

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2002

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tom 36

12

Effect of cyclic wood heterogeneity on the distribution of shear stresses in glue bonded joints

63%

Smardzewski J.

Folia Forestalia Polonica. Series B - Drzewnictwo

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2000

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tom 31

13

Impact of annual growth pattern on swelling of selected wood species

51%

Dobrowolska E., Macinska J.

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

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2021

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tom 115

14

Interaction of selected anthocyanins with erythrocytes and liposome membranes

51%

Bonarska-Kujawa D., Pruchnik H., Kleszczynska H.

Cellular and Molecular Biology Letters

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2012

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tom 17

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nr 2

Anthocyanins are one of the main flavonoid groups. They are responsible for, e.g., the color of plants and have antioxidant features and a wide spectrum of medical activity. The subject of the study was the following compounds that belong to the anthocyanins and which can be found, e.g., in strawberries and chokeberries: callistephin chloride (pelargonidin-3-O-glucoside chloride) and ideain chloride (cyanidin-3-O-galactoside chloride). The aim of the study was to determine the compounds’ antioxidant activity towards the erythrocyte membrane and changes incurred by the tested anthocyanins in the lipid phase of the erythrocyte membrane, in liposomes composed of erythrocyte lipids and in DPPC, DPPC/cholesterol and egg lecithin liposomes. In particular, we studied the effect of the two selected anthocyanins on red blood cell morphology, on packing order in the lipid hydrophilic phase, on fluidity of the hydrophobic phase, as well as on the temperature of phase transition in DPPC and DPPC/cholesterol liposomes. Fluorimetry with the Laurdan and Prodan probes indicated increased packing density in the hydrophilic phase of the membrane in the presence of anthocyanins. Using the fluorescence probes DPH and TMA-DPH, no effect was noted inside the hydrophobic phase of the membrane, as the lipid bilayer fluidity was not modified. The compounds slightly lowered the phase transition temperature of phosphatidylcholine liposomes. The study has shown that both anthocyanins are incorporated into the outer region of the erythrocyte membrane, affecting its shape and lipid packing order, which is reflected in the increasing number of echinocytes. The investigation proved that the compounds penetrate only the outer part of the external lipid layer of liposomes composed of erythrocyte lipids, DPPC, DPPC/cholesterol and egg lecithin lipids, changing its packing order. Fluorimetry studies with DPH-PA proved that the tested anthocyanins are very effective antioxidants. The antioxidant activity of the compounds was comparable with the activity of Trolox®.

15

Stateczność osiowo ściskanych cylindrycznych, anizotropowych powłok o średniej grubości

51%

Tracz W., Choruzyj M.

Acta Scientiarum Polonorum. Architectura

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2015

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tom 14

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nr 3

Korzystając z założeń kinematycznych Timoshenki, przedstawiono zagadnienie obliczania stateczności anizotropowych powłok cylindrycznych przy uwzględnieniu geometrycznej nieliniowości. Powłoka jest zbudowana z warstwowego materiału kompozytowego o jednej płaszczyźnie, która pokrywa się z jej powierzchnią środkową. Analizę numeryczną otrzymanych równań przeprowadzono metodą ortogonalizacji dyskretnej. Zbadano wpływ kąta nachylenia włókien warstwowego kompozytu włóknistego na wartości krytyczne.

16

Stabilization of erythrocytes against oxidative and hypotonic stress by tannins isolated from sumac leaves (Rhus typhina L.) and grape seeds (Vitis vinifera L.)

51%

Olchowik E., Lotkowski K., Mavlyanov S., Abdullajanova N., Ionov M., Bryszewska M., Zamaraeva M.

Cellular and Molecular Biology Letters

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2012

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tom 17

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nr 3

Erythrocytes are constantly exposed to ROS due to their function in the organism. High tension of oxygen, presence of hemoglobin iron and high concentration of polyunsaturated fatty acids in membrane make erythrocytes especially susceptible to oxidative stress. A comparison of the antioxidant activities of polyphenol-rich plant extracts containing hydrolysable tannins from sumac leaves (Rhus typhina L.) and condensed tannins from grape seeds (Vitis vinifera L.) showed that at the 5–50 μg/ml concentration range they reduced to the same extent hemolysis and glutathione, lipid and hemoglobin oxidation induced by erythrocyte treatment with 400 μM ONOO− or 1 mM HClO. However, extract (condensed tannins) from grape seeds in comparison with extract (hydrolysable tannins) from sumac leaves stabilized erythrocytes in hypotonic NaCl solutions weakly. Our data indicate that both hydrolysable and condensed tannins significantly decrease the fluidity of the surface of erythrocyte membranes but the effect of hydrolysable ones was more profound. In conclusion, our results indicate that extracts from sumac leaves (hydrolysable tannins) and grape seeds (condensed tannins) are very effective protectors against oxidative damage in erythrocytes.

17

Anizotropia właściwości mechanicznych płyt drewnopochodnych

51%

Kociszewski M.

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

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2015

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tom 56

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nr 3-4

18

Zmienność przestrzenna temperatury gleby w Polsce

51%

Rojek E., Usowicz B.

Acta Agrophysica

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2018

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tom 25

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nr 3

Celem badań było rozpoznanie i określenie przestrzennej zmienności temperatury w powierzchniowej warstwie gleby na obszarze Polski. Do badań wykorzystano dane pomiarowe wykonane w latach 1961-1975 w 88 stacjach meteorologicznych. Rozpatrywano jednomiesięczne okresy temperatur pochodzące z głębokości 5 cm. Do analiz zastosowano metody statystyczne i geostatystyczne. Rozpoznano zmienność przestrzenną temperatury gleby, wykorzystując empiryczne semiwariogramy oraz dopasowane do nich modele, dla których wyznaczono wartości samorodków, wartości progów wysycenia semiwariancji oraz zakresów przestrzennej zależności. Obliczono również wymiary fraktalne. Następnie, stosując metodę krigingu, na podstawie danych punktowych, wyznaczono powierzchniowe rozkłady temperatury gleby na obszarze Polski. Stwierdzono istotną i silną przestrzenną zależność temperatury gleby. Najlepiej dopasowanym modelem matematycznym semiwariogramu empirycznego była funkcja sferyczna z zakresem od 290 do 880 km. Wartości samorodka, wysycenia, jak i wymiaru fraktalnego rosły w okresie letnim, malały od jesieni do wiosny z najniższymi wartościami na koniec jesieni i początek zimy. Wskazują one, że w okresie wiosenno-letnim zachodzą dodatkowe procesy modyfikujące temperaturę gleby, głównie w wyniku bardziej zróżnicowanych opadów deszczu i większych zawartości frakcji piasku w środkowej części Polski. Semiwariogramy powierzchniowe wskazują na występowanie zmieniającej się w czasie anizotropii w rozkładzie temperatury gleby. Przestrzenne rozkłady temperatury gleby ukazują znaczące jej zróżnicowanie na obszarze Polski z ukierunkowaniem południkowym w okresie jesienno-zimowym i równoleżnikowym w okresie wiosenno-letnim.

19

Coefficient of optimal structure in relation to wood density in Norway spruce (Picea abies Karst.) and pine (Pinus sylvestris L.)

51%

Jakubowski M., Jelonek T.

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

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2012

|

tom 78

20

Szkolenie dla służb techniczno-inżynieryjnych w Fojutowie

45%

G.C.

Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie

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2015

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tom 56

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nr 3-4

Ograniczanie wyników

Effects of anisotropy in magnetotelluric soundings

Possible means of overcoming sedimentation by motile sea-picoplankton cells

Strengthening of veneers for 3D-forming

Surface anisotropy orients cell divisions in contact guided cells

Young modulus of face layer and core layer in three directions on the example of P2 particleboard

Gemini ester quat surfactants and their biological activity

Stress distribution in cell wall – inferring stress anisotropy from the pattern of buckling in the innermost cell wall layer

The anisotrophic nature of the strain of biodegradable film produced from TPS starch

Analiz pokazatelja strukturno-mekhanicheskojj neodnorodnosti drevesiny

Stress concentration around a circular opening in a wooden plate subjected to twisting moments

Anisotropy of mechanical properties of particleboard and medium density fibreboard in bending

Effect of cyclic wood heterogeneity on the distribution of shear stresses in glue bonded joints

Impact of annual growth pattern on swelling of selected wood species

Interaction of selected anthocyanins with erythrocytes and liposome membranes

Stateczność osiowo ściskanych cylindrycznych, anizotropowych powłok o średniej grubości

Stabilization of erythrocytes against oxidative and hypotonic stress by tannins isolated from sumac leaves (Rhus typhina L.) and grape seeds (Vitis vinifera L.)

Anizotropia właściwości mechanicznych płyt drewnopochodnych

Zmienność przestrzenna temperatury gleby w Polsce

Coefficient of optimal structure in relation to wood density in Norway spruce (Picea abies Karst.) and pine (Pinus sylvestris L.)

Szkolenie dla służb techniczno-inżynieryjnych w Fojutowie