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1

Effective diffusivity of moisture in low rank coal during superheated steam drying at atmospheric pressure

100%

Pakowski Z., Adamski R., Kwapisz S.

Chemical and Process Engineering

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2012

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issue 1

2

The Influence of the Forced Movement of Components on the Structure in Fabricated AlSi/CrxCy Composite Castings

100%

Dulęba A., Cholewa M., Scelina D.

Archives of Foundry Engineering

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2012

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issue 1

3

Depth Analysis of Crystalline Silicon Used for Radiation-Hard Detectors

100%

Moloi S., McPherson M.

Acta Physica Polonica A

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2017

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vol. 132

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issue 4

1387-1392

EN

Depth analysis of metal-doped crystalline silicon by the X-ray photoelectron spectroscopy technique is presented in this work. The results from this technique are used to complement those from previous techniques. The metals diffused into the silicon are gold, platinum, erbium, and niobium. In silicon, these metals induce defects that are responsible for relaxation behaviour of the material. Relaxation material is radiation-hard since the effects of radiation on devices fabricated on the material are suppressed. Considerable amounts of gold, platinum, and niobium are found in the silicon bulk. The results of this work are in good agreement with those reported earlier on the same samples using the Rutherford backscattering technique. The spectra of the natural contaminants, carbon and oxygen, are also analysed in this work.

4

Effective diffusivity of moisture in low rank coal during superheated steam drying at atmospheric pressure

100%

Pakowski Z., Adamski R., Kwapisz S.

Chemical and Process Engineering

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2012

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vol. 33

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issue 1

43-51

EN

The effective diffusivity of water in brown coal of Bełchatów mine was experimentally determined. The experiments were performed in superheated steam at 200°C and atmospheric pressure using slightly compressed pellets of cylindrical shape. The drying and temperature curves of the sample were used to identify diffusivity. An inverse problem was formulated and solved by the finite element method for 3D axially symmetric cylindrical geometry of the sample. A satisfactory fit of the simulated curves to experimental results was obtained. The obtained dependence of effective diffusivity on moisture content and temperature may be used in designing lignite dryers.

5

Diffusion Kinetics of Binary Ti-Ni Shape Memory Alloys

88%

Ucar N., Dogan S., Ozdemir A., Karakas S., Calik A.

Acta Physica Polonica A

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2017

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vol. 132

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issue 3

524-526

EN

In this work, the boriding of binary Ti-Ni shape memory alloys was carried out in a solid medium at 1173 and 1273 K for 2, 4, and 8 h using the powder pack method with Ekabor-Ni powders. The boride layer was characterized by optical microscopy and scanning electron microscopy. The obtained results show that boride layer thickness increases with the increasing boriding temperature and time. Depending on temperature and boride layer thickness, the diffusion process is thermally activated, with the mean value of the activation energy being close to 67 kJ/mol.

6

Statistical Properties of a Polymer Chain in the Environment with Low Concentration of Nanoparticles

88%

A. Tsehay D., Luo M.-B.

Acta Physica Polonica A

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2018

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vol. 133

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issue 5

1274-1280

EN

We have investigated the statistical properties of polymer in the environment with low concentration of nanoparticles by using large-scale molecular dynamics simulations. The scaling law for the mean square radius of gyration was examined and simulation results for the polymer lengths 64≤N≤144 yielding a reasonably accurate value of the Flory exponent ν=0.58 at weak polymer-nanoparticle interaction ε_{PN}. Within the same range of N, the mean asphericity of the chain is independent of N. We found that the polymer behaves like a self-avoiding walk chain at small ε_{PN} and a compact sphere at large ε_{PN}. The results are attributed to the increase in the contact between polymer and nanoparticles with increasing ε_{PN}. Normal diffusions of polymer are always observed at whatever ε_{PN} and size and concentration of nanoparticles. Our result shows that the normal diffusion behavior of polymer is independent of polymer's state even though there is a phase transition from a desorbed polymer phase at small ε_{PN} to an adsorbed polymer phase at large ε_{PN}.

7

Modeling of flow and mass transport in granular porous media

88%

Coutelieris F.

Open Physics

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2011

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vol. 9

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issue 4

962-968

EN

The scope of this work is to estimate the effective mass-transfer coefficient in a two-phase system of oil and water fluid droplets, both being in a porous medium. To this end, a tracer is advected from the flowing aqueous phase to the immobile non-aqueous one. Partitioning at the fluid-fluid interface and surface diffusion are also taken into account. By using spatial/volume-averaging techniques, the appropriately simplified boundary-value problems are described and numerically solved for the flow velocity field and for the transport problem. The problem was found to be controlled by the Peclet number of the flowing phase, the dimensionless parameter Λ, containing both diffusion and partition in the two phases, as well as the geometrical properties of the porous structure. It is also verified that the usually involved unit cell-configurations underestimate the mass transport to the immobile phase.

8

The Effect of Geometrical and Material Modification of Sound Diffusers on Their Acoustic Parameters

88%

Pilch A., Kamisiński T.

Archives of Acoustics

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2011

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vol. 36

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issue 4

9

Facilitated diffusion of glucosamine-6-phosphate synthase inhibitors enhances their antifungal activity.

88%

Janiak A., Cybulska B., Szlinder-Richter J., Borowski E., Milewski S.

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2002

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vol. 49

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issue 1

77-86

EN

N3-(4-Methoxyfumaroyl)-L-2,3-diaminopropanoic acid (FMDP) and 2-amino-2-deoxy-D-glucitol-6-phosphate (ADGP) are strong inhibitors of the essential fungal enzyme, glucosamine-6-phosphate synthase, but their antifungal activity is poor, due to slow penetration of these agents through the cytoplasmic membrane. In the present studies we have exploited the possibility of enhancement of ADGP and FMDP antifungal activity by improving their transport properties. It has been found that membrane-permeabilising polyene macrolides amphotericin B (AMB) and its N-methyl-N-fructosyl methyl ester derivative (MF-AME), at subinhibitory concentrations, facilitate diffusion of ADGP through the fungal cell membrane, thus allowing a decrease of its minimal inhibitory concentration (MIC). Synergistic effects have been observed for combinations of ADGP with AMB or MF-AME. Fractional inhibitory concentration (FIC) indexes, determined against a number of Candida spp., have been in the 0.18-0.81 range. Weak antifungal synergistic effects have been found for combinations of FMDP with AMB or MF-AME. ADGP can be easily encapsulated into unilamellar lipid vesicles. Liposomal preparations of ADGP demonstrated stronger antifungal activity against some fungal strains than free ADGP.

75%

Park S., Nam S.-W., Cho J.-Y., Lee S.-H., Hyun S.-K., Kim T.-S., Park S., Nam S.-W., Cho J.-Y., Lee S.-H., Hyun S.-K., Kim T.-S.

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vol. 65

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issue 4

16

A novel approach for calculating packed column height based on new correlation of mass transfer coefficient

75%

Rahbar-Kelishami A., Bahmanyar H., Hajamini Z.

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EN

The calculation of column’s height plays an important role in packed columns precise design. This research is based on experimentally measurement of mass transfer coefficients in different heights of packed column to predict its height. The objective of presented work is to introduce a novel conceptual method to predict column height via new correlation for mass transfer coefficient. As the mass transfer coefficient is decreased with increase of column height, the HTU’s are not constant figures along the column so this new approach is called increasing HTU’s. The results of the proposed idea were compared with other correlations and the conventional method i.e. constant HTU’s. Since the results are in very good agreement with experimental data comparing to conventional method, it seems this approach can be a turning point in design of all differential columns like packed columns. Making use of this method is suggested for design of differential columns.

17

Spectroscopic methods of studying enzyme action in wool fibre

63%

Fogorasi M., Heine E.

Open Chemistry

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2006

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vol. 4

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issue 4

786-797

EN

Enzymes may be used to develop an environmentally friendly alternative to the conventional polluting technologies in textile finishing. The action of the unlabeled and fluorescent labeled proteolytic enzymes subtilisin and trypsin on wool was examined. Scanning electron micrographs and a diffusion study, based on fluorescence microscopy, localized the enzymatic attack on the fiber. A kinetic study was carried out by monitoring the amino acid content of the treatment liquor. Enzymatic action is not confined to the fiber surface. To limit attack to the surface and reduce wool damage new treatment methods such as enzyme immobilization onto a solid carrier must be investigated.

18

American cat, czyli koty i ludzie w neuronauce

51%

Bazarnik A., Gąsiorek K.

Zeszyty Naukowe Towarzystwa Doktorantów Uniwersytetu Jagiellońskiego. Nauki Ścisłe

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2015

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issue 11

51-66

EN

The article presents a brief description of American studies from the ‘60s and the ‘70s in the field of neuroscience which led towards substantial changes in behavioral methods which enabled to modify permanently patterns of brain activity. Furthermore, cultural and historical background of these findings is discussed. First recordings of the brain’s spontaneous electrical activity in humans in the 1920’s made it possible to observe changes in brain’s activity, especially those that occur during learning processes. Based on learning theories that underlie changes in behavioral patterns: Pavlovian conditioning, and Thorndike’s operant conditioning, American researchers have shown that brain’s electrical activity may be considered as behavior and according to the principles of conditioning, it may be modified. Sterman’s further research on rocket fuel and sensorimotor rhythm in cats led to a spectacular achievement which was soon transformed into a complementary technique of reducing the number of epileptic seizures in humans. The new therapeutic method was named neurofeedback (or EEG biofeedback) and nowadays it can be applied in treating ADHD, ADD, mood disorders, anxiety disorders, chronic pain but also in mind fitness trainings. There are some characteristics of the American mentality which could have contributed to the global distribution of neurofeedback. However, traditional origins of learning how to modify brain and body functions can be found in taoism, hinduism, sufism and christianity.

PL

W artykule zaprezentowano krótki opis badań amerykańskich z lat sześćdziesiątych i siedemdziesiątych przeprowadzonych na gruncie neuronauki, które doprowadziły do zasadniczych zmian w technikach behawioralnych i umożliwiły trwałe modyfikowanie wzorca aktywności mózgu. Omówiono także kulturowe oraz historyczne tło tych odkryć. Uzyskanie pierwszego zapisu spontanicznej aktywności bioelektrycznej mózgu ludzkiego w latach dwudziestych XX wieku pozwoliło na dokładną obserwację zmian w jego pracy, szczególnie tych, które zachodzą podczas procesu uczenia się. W oparciu o podstawowe teorie uczenia się, stanowiące podłoże zmian wzorców behawioralnych: warunkowanie pawłowowskie oraz warunkowanie instrumentalne Thorndike’a, badacze amerykańscy udowodnili, że także aktywność bioelektryczna mózgu może być rozpatrywana jako zachowanie i, zgodnie z zasadami warunkowania, można ją modyfikować. Dalsze badania Stermana nad paliwem rakietowym i rytmem sensomotorycznym u kotów doprowadziły do spektakularnego osiągnięcia, które okazało się pomocne w redukcji ilości napadów padaczkowych u ludzi. Ta nowa metoda terapeutyczna została nazwana neurofeedback (lub EEG biofeedback) i obecnie znajduje również zastosowanie w leczeniu ADHD, ADD, zaburzeń nastroju, zaburzeń lękowych, bólu chronicznego, a także w treningach typu mind fitness. Prawdopodobnie istnieją takie cechy charakterystyczne dla amerykańskiej mentalności, które mogły przyczynić się do światowej dystrybucji metody neurofeedback. Tradycyjne korzenie uczenia się modyfikacji funkcji mózgu i ciała można zaś odnaleźć w taoizmie, hinduizmie, sufizmie oraz w chrześcijaństwie...

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Effective diffusivity of moisture in low rank coal during superheated steam drying at atmospheric pressure

The Influence of the Forced Movement of Components on the Structure in Fabricated AlSi/CrxCy Composite Castings

Depth Analysis of Crystalline Silicon Used for Radiation-Hard Detectors

Effective diffusivity of moisture in low rank coal during superheated steam drying at atmospheric pressure

Diffusion Kinetics of Binary Ti-Ni Shape Memory Alloys

Statistical Properties of a Polymer Chain in the Environment with Low Concentration of Nanoparticles

Modeling of flow and mass transport in granular porous media

The Effect of Geometrical and Material Modification of Sound Diffusers on Their Acoustic Parameters

Facilitated diffusion of glucosamine-6-phosphate synthase inhibitors enhances their antifungal activity.

Diversification of Socio-economic Development in Polish Municipalities in 2004-2016

Effect of diffusion and internal heat source on a two-temperature thermoelastic medium with three-phase-lag model

Adsorption with chemical reaction in porous catalyst pellets under alternate concentration fields. Uniform temperature case

Role of Acetone in the Formation of Highly Dispersed Cationic Polystyrene Nanoparticles

Bronchial Mucus as a Complex Fluid: Molecular Interactions and Influence of Nanostructured Particles on Rheological and Transport Properties

Effect of Mg Ratio on the Extraction of Dy from (Nd,Dy)-Fe-B Permanent Magnet Using Liquid Mg

A novel approach for calculating packed column height based on new correlation of mass transfer coefficient

Spectroscopic methods of studying enzyme action in wool fibre

American cat, czyli koty i ludzie w neuronauce