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1

Physical properties and caffeine release from creams prepared with different oils

100%

Wojciechowska K., Zun M., Dwornicka D., Swiader K., Kasperek R., Poleszak E.

Current Issues in Pharmacy and Medical Sciences

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2014

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vol. 27

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issue 4

224-228

EN

Caffeine is a methylxanthine typically found in the Coffee Arabica L plant. Generally, caffeine is well-known as a orally administered mild stimulant of the central nervous system. However, for cosmetic purpose, caffeine is an active compound ingredient, at 7% concentration, in several anticellulite products. The efficiency of this mode of delivery is not fully understood. Hence, the aim of the study was to ascertain the effectiveness of particular carriers to release this ingredient. In so doing, we prepared six creams based upon different oils (Sesame oil, Rice oil, Walnut oil, Coconut oil, Sweet almond oil and Jojoba oil), containing 5% of caffeine, and compared the release of the substance from the obtained preparations. Initially, all of the creams were subjected to a variety of physical tests, among these being for slippage and spreadability. Furthermore, their rheological properties were evaluated. Subsequently, the creams were tested for caffeine release. In the slippage and spreadability tests, the coconut oil-based cream was revealed as having the best parameters. However, the rheological tests showed that all of the preparations had the pseudoplastic character of flowing according to the Ostwald de Waele power law model. The power low index (n) for all the preparations was from 0.2467-0.3179 at 20°C and 0.2821-0.3754 at 32°C. At 20°C, the Sesame oil-, Walnut oil-, Sweet almond oil- and Jojoba oil-based creams were thixotropic, but at 32°C, thixotropy appeared only in the Walnut oil-based creams. The release studies, conducted by way of an extracting chamber (according to Polish Pharmacoeia IX) in the Paddle Apparatus (according to Polish Pharamcopoeia IX), showed that the amount of released caffeine is the largest in the case of Jojoba oil-based cream, at 85.23% ± 0.8% (SD), and the least in the case of Coconut oil-based cream, at 62,78%± 0.87% (SD).

2

The inflluence of emulsifiers on physical properties and release parameters of creams with caffeine

100%

Dwornicka D., Wojciechowska K., Zun M., Kasperek R., Swiader K., Szumilo M., Poleszak E.

Current Issues in Pharmacy and Medical Sciences

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2015

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vol. 28

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issue 2

81-84

EN

Caffeine is well known alkaloid chemical compound belonging to the methyl-xanthines group. It is an active substance that is found in many cosmetic products, as it has a stimulating action on both the central nervous system and the metabolism. Commercially available topical formulations normally contain 3% of caffeine and 7% anticellulite products. The aim of our work was to investigate the properties of four cream preparations. These consisted of 5% of caffeine and one of four different emulsifiers (GSC, Sodium polyacrylate, Emulsifying Base, MDS). In our work, we compared the physical properties (spreadability, slip and tenacity), the rheological structure of the resulting creams and the caffeine release from the obtained preparations. The results showed that the properties of these creams and their drug release depended upon the kind of the emulsifiers utilised. What is more, all preparations have a pseudoplastic character of flow and most of them have significant thixotropy. Furthermore, the amount of released caffeine is the largest from the MDS cream, and this emulsifier seems to be the most optimal in all the examined items.

3

Effect of Calcined Colemanite Addition on the Rheological Behaviour of Porcelain Suspension

100%

Özdemir Y., Akpınar S., Abbak S., Evcin A.

Acta Physica Polonica A

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2017

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vol. 132

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issue 3

825-829

EN

A standard composition for hard porcelain production was prepared by mixing 50 wt% kaolin, 25 wt% potassium feldspar and 25 wt% quartz. Calcined colemanite powders were added to the porcelain formulation by replacing the potassium feldspar up to 5 wt% to explore its effect on the rheological behaviour of porcelain slip casting. A rheological study has been carried out in order to optimize the processing of the slip casting by using a rotational stress-controlled rheometer. The measurements were performed at constant temperature (25°C) using a parallel plate configuration. Sweep measurements were then conducted in the shear rates ranging from about 0.1-1000 s¯¹. The stability of the suspensions with ammonium polyacrylate (Darvan 821A) was determined in order to select the suitable dispersant amount. In order to achieve casting of acceptable characteristics on a plaster of Paris mould, the slurry should have the appropriate thixotropic or shear-thinning behaviours. Therefore, the same favourable thixotropic behaviour of slurries of different amount of calcined colemanite powders, the solid contents of the slurries have been optimised.

4

Impact of carrageenan addition on rheological characteri-sation of some hydrocolloid aqueous solutions during long-lasting agitating with rotational speed changes

88%

Neupauer K., Kabziński M.

Chemical and Process Engineering

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2019

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vol. 40

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issue 4

5

Mixing system for highly concentrated fine-grained suspensions

88%

Moravec J., Jirout T., Rieger F., Krátký L.

Polish Journal of Chemical Technology

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2009

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vol. 11

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issue 4

52-56

EN

The mixing equipment for highly concentrated fine-grained suspensions must be designed differently from the equipment in which a suspension with a low concentration of the solid phase or bigger particles is mixed. It is due to the different rheological properties of the suspensions. In this work we are trying to find a suitable mixing system for a highly concentrated fine-grained suspension. The aim was to determine an effect of particular geometrical parameters of the tested mixing systems on a suspension process, especially from the energetic viewpoint. The energetic costs of all the used mixing systems were compared on the basis of the power consumption which was necessary for reaching the state of sufficient suspension movement in the whole mixed bulk. As a result, it was confirmed that multistage impellers can be used even in standard vessels (with a liquid level height equal to a vessel diameter) with a profit. During experiments, the state of sufficient movement was determined by a visual observation of the suspension at the vessel bottom, at the wall and also at the suspension level.

6

THE INFLUENCE OF THE ADDITION OF COLLAGEN ON THE RHEOLOGICAL PROPERTIES OF CHITOSAN CHLORIDE SOLUTIONS

88%

Owczarz P., Rył A., Modrzejewska Z., Dziubiński M.

Progress on Chemistry and Application of Chitin and its Derivatives

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2017

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vol. 22

176 - 189

EN

Colloidal solutions of chitosan of crab origin with the addition of collagen obtained from cowhide were studied. Were presents the influence of collagen concentration and the method of preparing the sample on the obtained mechanical properties of the solutions and the observed phase transition temperature. Rheological measurements were performed to determine the viscoelastic properties and phase transition temperatures of these solutions. The study was conducted in the temperature range of 5–60°C with the use of classical techniques of rotational rheometry in the cone-plate measurement system. A significant influence of a collagen addition to chitosan chloride solutions on the viscoelastic properties of the systems was observed. The addition of collagen in all the cases increased the sol–gel phase transition temperature in comparison with the chitosan chloride solution containing β-glycerophosphate.

7

Analysis of the effect of various types of limestone as a main constituent of cement on the chosen properties of cement pastes and mortars

75%

Gołaszewski J., Cygan G., Gołaszewska M., Gołaszewski J., Cygan G., Gołaszewska M.

Archives of Civil Engineering

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2019

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vol. 65

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issue 3

8

Pre-stress losses in FRP pre-stressed reinforced concrete – subject overview

75%

Przygocka M., Kotynia R., Przygocka M., Kotynia R.

Archives of Civil Engineering

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2018

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vol. 64

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issue 4-II

9

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

75%

Odziomek M., Kalinowska M., Płuzińska A., Rożeń A., Sosnowski T. R.

Chemical and Process Engineering

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2017

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vol. 38

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issue 2

10

Effect of high hydrostatic pressure on structure of gelatin gels

75%

Kulisiewicz L., Baars A., Delgado A.

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2007

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vol. 55

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issue 2

11

Targeted modification of the composition of polymer systems for industrial applications

75%

Ondrušová D., Labaj I., Pajtášová M., Vršková J., Božeková S., Feriancová A., Skalková P., Ondrušová D., Labaj I., Pajtášová M., Vršková J., Božeková S., Feriancová A., Skalková P.

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2021

12

Blood rheological properties and methods of their measurement

63%

Pryzwan T., Dolibog P., Kierszniok K., Pietrzyk B.

Annales Academiae Medicae Silesiensis

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2023

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issue 78

1-10

PL

Krew, z fizycznego punktu widzenia, to układ wielofazowy oraz wieloskładnikowy; osocze jest fazą zwartą, a elementy morfotyczne są fazą rozproszoną. Aby określić prawidłowe właściwości reologiczne konieczna jest analiza prędkości przepływu. Podczas wolnego przepływu może dochodzić do wzrostu agregacji krwinek, za co odpowiadają fibrynogen oraz globuliny. Ważna jest także odkształcalność krwinek czerwonych, szczególnie podczas przepływu przez naczynia włosowate, gdzie muszą się dostosować do mniejszej średnicy naczyń. Lepkość określa się jako wewnętrzny opór przepływu; jeśli będziemy rozpatrywać krew jako składową dwóch warstw, które są równoległe, to lepkość opisywana jest przez tarcie dwóch sąsiadujących ze sobą warstw. Warstwy cieczy przemieszczają się z różną prędkością równolegle względem siebie i powstaje gradient prędkości (szybkość ścinania). Aby go wytworzyć, potrzebna jest siła poruszająca warstwy, określana jako naprężenie ścinające. Agregaty z krwinek są obserwowane zarówno fizjologicznie, jak i w przebiegu niektórych chorób, takich jak choroba niedokrwienna serca, zawał mięśnia sercowego i miażdżyca. Wyróżnia się dwa rodzaje czynników sprzyjających tworzeniu się agregatów: zewnętrzne – stężenie białek osocza, hematokryt oraz siły ścinania, i wewnętrzne, które stanowią kształt i odkształcalność erytrocytów oraz właściwości błony komórkowej. Przy hiperfibrynogenemii wzrasta agregacja erytrocytów, lepkość osocza i opór mikronaczyniowy. Laserowo-optyczny rotacyjny analizator krwinek czerwonych (laser-assisted optical rotational cell analyzer – LORCA) służy do badań odkształcalności oraz agregacji erytrocytów. Łączy techniki sylektometrii z ektacytometrią. Tworzenie się trójwymiarowej struktury krwinek czerwonych ma istotny wpływ na pomiar lepkości krwi oraz przepływu krwi przy niskiej prędkości ścinania.

EN

From the physical point of view, blood is a multi-phase and multi-component system; plasma is the dispersion medium and the morphotic elements are the dispersed phase. Flow rate analysis is essential to determine the correct rheological properties of blood. Slow blood flow can lead to increased erythrocyte aggregation, which is due to fibrinogen and globulins. The deformability of red blood cells is also important, especially during flow through the capillaries, where they must adapt to the smaller diameter of the vessels. Viscosity is defined as the internal resistance to flow; if we consider blood as a component of two parallel layers, then viscosity is described by the friction of two adjacent layers. The liquid layers move at different velocities parallel to each other, and a velocity gradient is created. To create it, a force is needed to move the layers, which is referred to as shear stress. Erythrocyte aggregates are observed physiologically as well as in the course of some diseases such as ischemic heart disease, myocardial infarction and atherosclerosis. There are two types of factors inducing the formation of aggregates: the external factors include the plasma protein concentration, hematocrit and shear forces; the internal factors are the shape and deformability of the erythrocytes in addition to the properties of the cell membrane. Also in hyperfibrinogenemia, erythrocyte aggregation, plasma viscosity and microvascular resistance increase. The laser-assisted optical rotational cell analyzer (LORCA) is used to test the deformability and aggregation of erythrocytes. It combines the techniques of syllectometry with ektacytometry. The formation of a three-dimensional structure of red blood cells has a significant impact on the measurement of blood viscosity and low shear rate blood flow.

13

Numerical calculations of the consolidation of flotation weste landfill

51%

Strzelecki T., Bartlewska-Urban M., Strzelecki T., Bartlewska-Urban M.

Archives of Civil Engineering

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2011

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issue 2

Refine search results

Physical properties and caffeine release from creams prepared with different oils

The inflluence of emulsifiers on physical properties and release parameters of creams with caffeine

Effect of Calcined Colemanite Addition on the Rheological Behaviour of Porcelain Suspension

Impact of carrageenan addition on rheological characteri-sation of some hydrocolloid aqueous solutions during long-lasting agitating with rotational speed changes

Mixing system for highly concentrated fine-grained suspensions

THE INFLUENCE OF THE ADDITION OF COLLAGEN ON THE RHEOLOGICAL PROPERTIES OF CHITOSAN CHLORIDE SOLUTIONS

Analysis of the effect of various types of limestone as a main constituent of cement on the chosen properties of cement pastes and mortars

Pre-stress losses in FRP pre-stressed reinforced concrete – subject overview

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

Effect of high hydrostatic pressure on structure of gelatin gels

Targeted modification of the composition of polymer systems for industrial applications

Blood rheological properties and methods of their measurement

Numerical calculations of the consolidation of flotation weste landfill