Search results

1

High Temperature Study of Industrial Slag from Further Modelling Point of View

100%

Ślęzak M., Karbowniczek M., Migas P., Ślęzak W., Ślęzak M., Karbowniczek M., Migas P., Ślęzak W.

Archives of Metallurgy and Materials

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2021

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vol. 66

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issue 2

2

Denaturation and aggregation of lysozyme in water-ethanol solution

100%

Szymańska A., Hornowski T., Ślósarek G.

Acta Biochimica Polonica

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2012

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vol. 59

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issue 2

317-322

EN

We have applied rheological methods for the analysis of ethanol-lysozyme interaction during the process of denaturation and aggregation of the protein. At low concentration of ethanol a destruction of the hydration shell of lysozyme is observed. With the increase in the ethanol concentration a structural transformation takes place. It leads to the formation of a protein aggregate with an elongated structure. The rheological characteristics of lysozyme-water-ethanol solution changes from Newtonian to pseudoplastic.

3

The influence of the viscosity of the ointment vehicles magisterial topical preparations, on the speed transfer of biologically active substances

100%

Glogowski A., Kolodziejska J., Kolodziejczyk M. K., Zgoda M. M.

Current Issues in Pharmacy and Medical Sciences

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2015

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vol. 28

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issue 3

212-218

EN

The aim of this study was to analyze the morphological parameters (viscosity, viscous elasticity and the rate of volatile component loss) of salicylic and boric acid-containing magisterial formulae (ointments). Moreover, the effects of these parameters on the diffusion rate of a therapeutic agent (salicylic acid) to an in vitro external compartment were analyzed. Finally, the applicatory properties of the ointments prepared by way of a conventional technique (in a mortar) and with the aid of an unguator, were compared. The rheological parameters of the analyzed ointments suggest that the preparations made with an aid of an unguator, irrespective of the physicochemical characteristics of their vehicles, are characterized by higher values of diffusion coefficient (D). In addition, conventionally-prepared formulae containing salicylic were shown to be characterized by better viscous elasticity. Surprisingly, irrespective of the preparation technique, the ointments based on an absorptive vehicle (containing lanolin) were characterized by similar viscous elasticity. The rate of volatile (water) component loss from ointments containing a 3% solution of boric acid suggests that such formulae lose no more than 2.3% of their mass when exposed at 37℃. Therefore, the viscosity of such ointments applied onto a patient’s skin should remain relatively stable.

4

Mobility of interacting inorganic nanoparticles

88%

Dziedzic-Kocurek K., Fornal P., Stanek J.

Nukleonika

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2015

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vol. 60

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issue 1

19-22

EN

The mobility of the 110 nm-Fe2O3 particles in a viscous sucrose solution depends on the concentration of the nanoparticles. When the average particle–particle nearest neighbor distance is less than 250 nm, the particle interaction slows down their mobility. When is more than 170 nm, the small mobility of nanoparticles does not depend on their concentration. The critical distance is approximately equal to 2Rh = 260 nm, where Rh is the hydrodynamic radius, determined by the dynamic light scattering (DLS) method.

5

THE INFLUENCE OF EXCIPIENTS ON STABILITY OF VISCOUS EYE DROPS WITH DEXPANTHENOL IN PHARMACEUTICAL PRACTICE

88%

Savić V. L., Živković J., Stanković M. I., Antunović M., Basić Z., Nikolić I.

Acta Poloniae Pharmaceutica - Drug Research

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2019

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vol. 76

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issue 5

845-853

EN

Conventional eye drops exhibit weak bioavailability due to the unique physiology and anatomy of the eye. In order to increase eye drops viscosity, different concentrations of Carbopol® 940 (0.08% and 0.20%) were used. The aim of the study was to indicate the advantages and examine the influence of preservatives and the concentrations of viscosity increasing agents on the quality of magistral viscous eye drops with dexpanthenol (DXP). The quality of the prepared formulations was tested using physico-chemical methods and biological tests. pH Value measurement was done by the potentiometric method). Viscosity measurements of the samples were performed according to Ph. Eur. 9.0. DXP content was determined by reversed-phase high-pressure liquid chromatography. Sterility testing was performed using direct sample inoculation. The results indicate that pH values of eye drops with preservatives are lower than pH values of preservative-free formulations. All formulations have recovery values that meet the requirements of the European Pharmacopoeia. The DXP content in preservative-free eye drops increased slightly during testing, unlike the DXP content in eye drops with preservatives. The formulations remained sterile during 45 days after preparation, stored at room temperature, protected from light. DXP viscous eye drops may be prepared in pharmaceutical practice using the proposed viscosity increasing agent (Carbopol® 940) and preparation procedure. All formulations express stability for 45 days after preparation. Preservative-free DXP eye drops with Carbopol® 940 concentrations of 0.08% and 0.20% show maximal stability, provide an optimal concentration of DXP (3.0%), and therefore have an advantage in pharmaceutical practice.

6

Physico chemical properties of irradiated i-SANEX diluents

75%

Mossini E., Macerata E., Giola M., Brambilla L., Castiglioni C., Mariani M.

Nukleonika

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2015

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vol. 60

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issue 4

893-898

EN

The development of effective processes to recover minor actinides from spent nuclear fuel cannot leave out of consideration the evaluation of the impact of ionizing radiations on safety, fluid dynamics and extraction efficiency. It is common knowledge from the literature that radiation damage mainly affects the diluents and, indirectly, the extractants [1], but a lack of knowledge remains regarding the radiolytic behavior of innovative selective actinide extraction (i-SANEX) diluents [2, 3]. As natural prosecution of the work already performed on diluted nitric acid solutions [4], 0.44 M nitric acid solutions were irradiated in contact with a mixture of kerosene + 5 vol.% 1-octanol by a Co-60 source at 2.5 kGy/h dose rate and up to 100 kGy absorbed dose, conditions of interest for the future industrial facility. Density, viscosity, acidity, nitrate anion concentration and phase transfers were systematically measured before and after γ-irradiation. This was performed because radiation-induced modifications of these parameters may induce alterations of both the fluid dynamics and the separation performances of the extracting system. The results suggest that the fluid-dynamics of the system should be unaltered. In fact, only slight alterations of the organic phase viscosity and of the aqueous phase acidity were measured after irradiation, suggesting the occurrence of limited phase transfers and of diluent by-products formation.

7

Temperature and concentration dependence of translational diffusion coefficient for human serum albumin in aqueous solutions at different pH

75%

Monkos K.

Annales Academiae Medicae Silesiensis

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2013

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vol. 67

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issue 3

184-193

EN

B A C K G R O U N D The aim of the present paper is to investigate the temperature and concentration dependence of the translational diffusion coefficient for human serum albumin in aqueous solutions at neutral pH and at the isoelectric point. M A T E R I A L A N D M E T H O D S The viscosity of human serum albumin aqueous solutions at pH 4.7 and 7.0 was measured at temperatures ranging from 5oC to 45oC and in a wide range of con-centrations. The measurements were performed with an Ubbelohde-type capillary microviscometer. R E S U L T S The translational diffusion coefficient of a protein in infinitely dilute solutions Do(T) can be calculated from the generalized Stokes-Einstein equation if the hydrodynamic radius of the studied protein is known. For hydrated human serum albumin, this equation gives Do(T) in the range of 3.45 x 10-11 m2/s (at 5oC) to 10.0 x 10-11 m2/s (at 45oC). The translational diffusion coefficient for higher concentrations of D(T,F) can be obtained from the relation: D(T,F) = Do(T)ho(T)/h(T,F), where F denotes the volume fraction and ho(T) and h(T, F) are the viscosities of water and the solution at temperature T, respectively. C O N C L U S I O N S The translational diffusion coefficient of human serum albumin in solutions both at pH 4.7 and 7.0 decreases linearly with increasing volume fraction, when  does not exceed the value of about 0.11. The dependence of the translational diffusion coefficient on volume fraction in the whole measured range of is non-linear and can be described by a stretched exponential function. The scaling parameters in this function are different at different values of pH. The dependence of the translational diffusion coefficient on temperature, in turn, can be described by the three-parameter Vogel-Tammann-Fulcher’s equation.

PL

W S T Ę P Celem niniejszej pracy jest zbadanie zależności współczynnika dyfuzji translacyjnej od temperatury i ułamka objętościowego dla albuminy surowicy ludzkiej w roztworach wodnych przy neutralnym pH oraz w punkcie izoelektrycznym. M A T E R I A Ł I M E T O D Y Lepkość wodnych roztworów albuminy surowicy ludzkie j przy pH 4,7 i 7,0 zmierzono w zakresie temperatur 5–45 o C i w szerokim zakresie stężeń. Pomiary wykonano za pomocą kapilarnego mikrowiskozymetru typu Ubbe-lohde’a. W Y N I K I Współczynnik dyfuzji translacyjnej białka dla roztworów rozcieńczonych D o (T) można obliczyć z uogólnionego równania Stokesa-Einsteina, jeżeli znany jest promień hydrodynamiczny badanego białka. Dla uwodnionej albuminy surowicy ludzkiej równanie to daje D o (T) w zakresie od 3,45 ¥ 10 -11 m 2 /s (w 5 o C) do 10,0 ¥ 10 -11 m 2 /s (w 45 o C). Współczynnik dyfuzji translacyjnej dla wyższych stężeń D(T, F ) można otrzymać z relacji: D(T, F ) = D o (T) h o (T)/ h (T, F ), w której F oznacza ułamek objętościowy a h o (T) i h (T, F ) to lepkości, odpowiednio, wody i roztworu w temperaturze T. W N I O S K I Współczynnik dyfuzji translacyjnej albuminy surowicy ludzkiej w roztworach wodnych zarówno przy pH 4,7 jak i 7,0 maleje liniowo wraz ze wzrostem ułamka objętościowego, jeżeli F nie przekracza wartości około 0,11. Zależność współczynnika dyfuzji translacyjnej od ułamka objętościowego w całym mierzonym zakresie F jest nieliniowa i można ją opisać rozciągniętą funkcją wykładniczą. Parametry skalowania w tej funkcji są różne przy różnych wartościach pH. Z kolei zależność współczynnika dyfuzji translacyjnej od temperatury może być opisana przez trójparametryczne równanie Vogela-Tammanna-Fulchera.

8

Influence of phosphorohydrazone derivatives of benzopyrones on polymerization and viscosity of fibrin

75%

Michalska M., Pająk W., Kołodziejska J., Łazarenkow A., Nawrot-Modranka J.

Acta Biochimica Polonica

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2008

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vol. 55

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issue 3

613-617

EN

The synthesis and antitumour and antibacterial activity of coumarin and chromone phosphorohydrazones have been reported. This study describes influence of phosphorohydrazones derivatives of coumarin and chromone on the polymerization and viscosity of fibrin. The fibrin polymerization assay was performed by the Shen and Lorand method and the clot viscosity was measured on the basis of Shen and Lorand and Marchi and coworkers methods. Among the eight compounds tested, one coumarin derivative and two chromone derivatives showed significant activity.

9

Axi-symmetric ice sheet flow with evolving anisotropic fabric

75%

Staroszczyk R.

Bulletin of the Polish Academy of Sciences: Technical Sciences

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2006

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vol. 54

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issue 4

10

Activation energy of viscous flow for some globular and non-globular proteins obtained from viscosity measurements and modified Arrhenius equation

63%

Monkos K.

Annales Academiae Medicae Silesiensis

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2009

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vol. 63

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issue 4

27-38

EN

BACKGROUND: The aim of the present paper was investigation of the temperature dependence of the activation energy of viscous fl ow for some proteins in aqueous solutions. MATERIAL AND METHODS: The viscosity of hen egg-white lysozyme, bovine 􀈕-lactoglobulin, and human, bovine and porcine IgG immunoglobulin aqueous solutions was measured at temperatures ranging from 5oC to 55oC and in a wide range of concentrations. The measurements were performed with an Ubbelohdetype capillary microviscometer. RESULT S : The average value of the activation energy of viscous fl ow ΔE can be experimentally obtained from the slope of the line that represents the dependence of the liquid viscosity η (in logarithmic scale) versus a reciprocal of the absolute temperature (T-1). The functional dependence of ΔE on temperature can be obtained from strict defi nition ΔE = R[dlnη/d(T-1)], where R is the gas constant and from a three parameters modifi ed Arrhenius formula which gives an analytical function describing the viscosity-temperature dependence for proteins solutions in a wide range of temperatures. As appears, ΔE obtained in such a way decreases with increasing temperature according to a square function. The parameters of this function have been obtained for all studied proteins. CONCLUSIONS: The obtained results show that square function describes the temperature dependence of ΔE both for water, solutions and proteins themselves. One of the main factor which infl uence the activation energy is a molecular mass of protein. However, the results obtained for the studied immunoglobulins IgG show that this factor is not the only one.

PL

WSTĘP: Celem niniejszej pracy było zbadanie temperaturowej zależności energii aktywacji przepływu lepkiego dla kilku białek w roztworach wodnych. MATERIAŁ I METODY: Lepkość wodnych roztworów lizozymu jaja kurzego, β-laktoglobuliny bydlęcej oraz ludzkiej, bydlęcej i świńskiej immunoglobuliny IgG zmierzono w zakresie temperatur od 5oC do 55oC i w szerokim zakresie stężeń. Pomiary wykonano przy pomocy kapilarnego mikrowiskozymetru typu Ubbelohde’a. WYNIKI: Średnią wartość energii aktywacji przepływu lepkiego ΔE można doświadczalnie otrzymać z nachylenia prostej przedstawiającej zależność lepkości cieczy η (w skali logarytmicznej) od odwrotności temperatury bezwzględnej (T-1). Funkcyjną zależność ΔE od temperatury można otrzymać z dokładnej definicji ΔE = R[dlnη/d(T-1)], gdzie R jest stałą gazową oraz z trójparametrycznego zmodyfi kowanego równania Arrheniusa, które daje analityczną funkcję opisującą temperaturową zależność lepkości dla roztworów białek w szerokim zakresie temperatur. Jak się okazuje, ΔE otrzymana w ten sposób maleje ze wzrostem temperatury zgodnie z funkcją kwadratową. Parametry tej funkcji zostały wyznaczone dla wszystkich badanych białek. WNIOSKI: Otrzymane wyniki pokazują, że funkcja kwadratowa opisuje temperaturową zależność ΔE zarówno dla wody, roztworów jak i samych białek. Jednym z głównych czynników wpływających na energię aktywacji jest masa molowa białka. Jednakże, wyniki otrzymane dla badanych immunoglobulin IgG pokazują, że nie jest to czynnik jedyny.

11

A comparative study on translational diff usion coeffi cient for some mammalian serum albumins

63%

Monkos K.

|

EN

BACKGROUND The aim of the present paper is investigation of the volume fraction dependence of the translational diffusion coefficient for some mammalian serum albumins in aqueous solutions. MATERIAL AND METHODS The viscosity of bovine, equine, ovine and rabbit serum albumin aqueous solutions was measured at temperatures ranging from 5oC to 45oC and in a wide range of concentrations. The measurements were performed with an Ubbelohde-type capillary microviscometer. RESULTS Translational diffusion coefficient at infinitely dilute solutions Do(T) can be calculated from generalized Stokes-Einstein equation if the hydrodynamic radius of albumin is known. It gives Do(T) in the range from 3.5×10-11 m2 /s (at 5oC) to 10.2 10-11 m2 /s (at 45oC) for bovine serum albumin, from 3.59×10-11 m2 /s (at 5oC) to 10.4 10-11 m2 /s (at 45oC) for equine serum albumin, from 3.42×10-11 m2 /s (at 5oC) to 9.92×10-11 m2 /s (at 45oC) for ovine serum albumin, and from 3.36×10-11 m2 /s (at 5oC) to 9.74×10-11 m2 /s (at 45oC) for rabbit serum albumin. Translational diffusion coefficient for higher concentrations D(T,φ) can be obtained from the relation: D(T,φ) = Do(T)Ηo(T)/Η(T,φ), where φ denotes volume fraction and Ηo(T) and Η(T,φ) are viscosities of water and solution, respectively, at temperature T. CONCLUSIONS The obtained results show that the translational diffusion coefficient decreases linearly with increasing volume fraction, when φ does not exceed the value of about 0.1. The dependence of the translational diffusion coefficient on volume fraction in a broader range of φ, i.e. from dilute to concentrated solutions, is nonlinear and can be described by a stretched exponential function.

PL

WSTĘP Celem niniejszej pracy jest zbadanie zależności współczynnika dyfuzji translacyjnej od ułamka objętościowego dla albumin surowicy kilku ssaków w roztworach wodnych. MATERIAŁ I METODY Lepkość wodnych roztworów albuminy surowicy wołowej, końskiej, owczej i króliczej zmierzono w zakresie temperatur od 5oC do 45oC i w szerokim zakresie stężeń. Pomiary wykonano przy pomocy kapilarnego mikrowiskozymetru typu Ubbelohde’a. WYNIKI Współczynnik dyfuzji translacyjnej dla roztworów rozcieńczonych Do(T) można obliczyć z uogólnionego równania Stokesa-Einsteina, jeżeli znany jest promień hydrodynamiczny albuminy. Daje to Do(T) w zakresie od 3.5×10-11 m2 /s (w 5oC) do 10.2×10-11 m2 /s (w 45oC) dla albuminy surowicy wołowej, od 3.59×10-11 m2 /s (w 5oC) do 10.4×10-11 m2 /s (w 45oC) dla albuminy surowicy końskiej, od 3.42×10-11 m2 /s (w 5oC) do 9.92×10-11 m2 /s (w 45oC) dla albuminy surowicy owczej i od 3.36×10-11 m2 /s (w 5oC) do 9.74×10-11 m2 /s (w 45oC) dla albuminy surowicy króliczej. Współczynnik dyfuzji translacyjnej dla wyższych stężeń D(T,φ) można otrzymać z relacji: D(T,φ) = Do(T)Ηo(T)/Η(T,φ), w której φ oznacza ułamek objętościowy a Ηo(T) i Η(T,φ) są, odpowiednio, lepkością wody i roztworu w temperaturze T. WNIOSKI Otrzymane wyniki pokazują, że współczynnik dyfuzji translacyjnej maleje liniowo wraz ze wzrostem ułamka objętościowego, jeżeli φ nie przekracza wartości około 0.1. Zależność współczynnika dyfuzji translacyjnej od ułamka objętościowego w szerszym zakresie φ , tzn. dla roztworów od rozcieńczonych do stężonych, jest nieliniowa i można ją opisać rozciągniętą funkcją wykładniczą.

Refine search results

High Temperature Study of Industrial Slag from Further Modelling Point of View

Denaturation and aggregation of lysozyme in water-ethanol solution

The influence of the viscosity of the ointment vehicles magisterial topical preparations, on the speed transfer of biologically active substances

Mobility of interacting inorganic nanoparticles

THE INFLUENCE OF EXCIPIENTS ON STABILITY OF VISCOUS EYE DROPS WITH DEXPANTHENOL IN PHARMACEUTICAL PRACTICE

Physico chemical properties of irradiated i-SANEX diluents

Temperature and concentration dependence of translational diffusion coefficient for human serum albumin in aqueous solutions at different pH

Influence of phosphorohydrazone derivatives of benzopyrones on polymerization and viscosity of fibrin

Axi-symmetric ice sheet flow with evolving anisotropic fabric

Activation energy of viscous flow for some globular and non-globular proteins obtained from viscosity measurements and modified Arrhenius equation

A comparative study on translational diff usion coeffi cient for some mammalian serum albumins