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Photoinduced Mass Transport in Liquids

Photoinduced Mass Transport in Liquids

Optically induced changes in the concentration distribution of Fluorescein and DCM dye solutions were investigated, with their dependences on the laser intensity and optical properties of solvent examined. In the experiments we used a thin solution layer (~70 μm) between two glass plates, which was exposed to CW laser radiation (γ = 523 nm). Under intensive laser illumination a transport of dissolved dye was observed. The distribution of solution concentration was analyzed using a low-intensity CW laser focused beam. The spectroscopy methods were employed to reveal differences between the absorption spectra of the solution before and after exposure. The solution concentration was proved to change around the exposed spot.

Open access
Thickness Optimisation of Textiles Subjected to Heat and Mass Transport during Ironing

Abstract

Let us next analyse the coupled problem during ironing of textiles, that is, the heat is transported with mass whereas the mass transport with heat is negligible. It is necessary to define both physical and mathematical models. Introducing two-phase system of mass sorption by fibres, the transport equations are introduced and accompanied by the set of boundary and initial conditions. Optimisation of material thickness during ironing is gradient oriented. The first-order sensitivity of an arbitrary objective functional is analysed and included in optimisation procedure. Numerical example is the thickness optimisation of different textile materials in ironing device.

Open access
Potential of Prediction Quantification and Trends in Transport Requirements as Tool of Transport Management and Development

Abstract

The basic aim of managers in transport is to preserve and expand their share of the transport market. This should be done through prioritising quality and customer service, preservation and expansion field of transport enterprise activity to transport market on the basic of priority orientation to quality and customer, maintaining transport networks and applying the latest knowledge from research. It should also involve making a contribution to favourable indicators of economic activity, and a consideration of environmental change. This paper deals with customer requirements, the possibility of quantifying customer requirements and the recognition of future trends on the basis of assessments of recent quantitative results and the application of managers’ knowledge and techniques.

Open access
Application of analytic element method in hydrogeology

Abstract

The analytic element method (AEM) has been successfully used in practice worldwide for many years. This method provides the possibility of fast preliminary quantitative analysis of the hydrogeological systems or boundary conditions of the numerical models, as it is shown in the case study of groundwater source of the city of Vrbas. The AEM is also applicable for the initial analysis of a hydrogeological system, which is of particular importance in case of excess pollution that cannot be predicted where it could happen. One example of the application of the AEM is presented in this article. The analytical model is calibrated based on the measured data from several drilled monitoring wells, and this was the base for the numerical model of the contaminant transport. In this case, the AEM enabled the quick access to information on the hydrogeological system and effective response to excess pollution.

Open access
Visualisation of Liquid Flow Phenomena in Textiles Applied as a Wound Dressing

Abstract

The aim of this work was to visualise liquid transport in textiles. Knowledge of the transport phenomena allows for the design of textiles for various applications, e.g., comfortable to wear filtration and wound dressing. To visualise liquid transport through textiles, three test methods were explored. The first one was the high spatial resolution magnetic resonance imaging (MRI) technique (also referred to as nuclear magnetic resonance (NMR) microscopy). It allowed the observation of the pathways of liquid flow through textiles. In the second method, a thermographic camera was used to record temperature changes and assess the liquid flow in the textile. The third method was using a high-speed video camera to observe the liquid transport within the textile. Two types of textiles were studied: a double-layer knitted fabric and a woven fabric, both made from hydrophilic and hydrophobic fibres (cotton, viscose and polypropylene). The knitted fabrics were tested as a new type of wound dressing, which trans

Open access
Numerical Optimisation of Thickness of Composite Bonnet for Neonates

Abstract

Head is the most sensitive body part of neonate. Head that is considerably uncovered causes the significant heat and moisture loss from the skin to the surrounding areas. The main goal is to optimise the thickness of a multilayer composite textile bonnet to secure the optimal skin parameters. Problem is solved using both sensitivity analysis and material derivative concept. An arbitrary objective functional is introduced, its first-order sensitivity is formulated by means of a direct approach. Numerical application is the thickness optimisation of a composite bonnet made of different textile materials.

Open access
Biodegradable polylactide and thermoplastic starch blends as drug release device – mass transfer study

Abstract

Four different compositions of polylactide/thermoplastic starch blends (PLA/TPS blends) for application as drug carriers were examined. Initially, using cyanocobalamin (1.355 kDa) as a model compound, the blend with the highest starch content (wt. 60%) was selected for further research of mass transfer phenomenon. In this case, different concentrations of acetaminophen (0.151 kDa), doxorubicin hydrochloride (0.580 kDa) and cyanocobalamin (1.355 kDa) were used for determination of particular releasing profiles. Besides from the comparative analysis of obtained results, the values of the overall mass transfer coefficient (K) were calculated for each of tested drug molecules. Depending on the size and properties of used compound, determined values of the coefficient range from 10−11 to 10−13 m/s. Based on these outcomes, it could be stated that PLA/TPS blend selected in preliminary research, seems to be preferred material for fabrication of long-term drug delivery systems, which could be successfully applied for example in anti-cancer therapy.

Open access
Stratigraphic and tectonic control of deep-water scarp accumulation in Paleogene synorogenic basins: a case study of the Súľov Conglomerates (Middle Váh Valley, Western Carpathians)

Abstract

The Súľov Conglomerates represent mass-transport deposits of the Súľov-Domaniža Basin. Their lithosomes are intercalated by claystones of late Thanetian (Zones P3 - P4), early Ypresian (Zones P5 - E2) and late Ypresian to early Lutetian (Zones E5 - E9) age. Claystone interbeds contain rich planktonic and agglutinated microfauna, implying deep-water environments of gravity-flow deposition. The basin was supplied by continental margin deposystems, and filled with submarine landslides, fault-scarp breccias, base-of-slope aprons, debris-flow lobes and distal fans of debrite and turbidite deposits. Synsedimentary tectonics of the Súľov-Domaniža Basin started in the late Thanetian - early Ypresian by normal faulting and disintegration of the orogenic wedge margin. Fault-related fissures were filled by carbonate bedrock breccias and banded crystalline calcite veins (onyxites). The subsidence accelerated during the Ypresian and early Lutetian by gravitational collapse and subcrustal tectonic erosion of the CWC plate. The basin subsided to lower bathyal up to abyssal depth along with downslope accumulation of mass-flow deposits. Tectonic inversion of the basin resulted from the Oligocene - early Miocene transpression (σ1 rotated from NW-SE to NNW-SSE), which changed to a transpressional regime during the Middle Miocene (σ1 rotated from NNE-SSW to NE-SW). Late Miocene tectonics were dominated by an extensional regime with σ3 axis in NNW-SSE orientation.

Open access
A metaheuristic for a numerical approximation to the mass transfer problem

Abstract

This work presents an improvement of the approximation scheme for the Monge-Kantorovich (MK) mass transfer problem on compact spaces, which is studied by Gabriel et al. (2010), whose scheme discretizes the MK problem, reduced to solve a sequence of finite transport problems. The improvement presented in this work uses a metaheuristic algorithm inspired by scatter search in order to reduce the dimensionality of each transport problem. The new scheme solves a sequence of linear programming problems similar to the transport ones but with a lower dimension. The proposed metaheuristic is supported by a convergence theorem. Finally, examples with an exact solution are used to illustrate the performance of our proposal.

Open access
Effect of macromolecular mass transport in microgravity protein crystallization

Abstract

To investigate the effect of macromolecular transport and the incorporation of protein aggregate impurities in growing crystals, experiments were performed on the International Space Station (ISS) and compared with control experiments performed in a 1G laboratory environment. Crystal growth experiments for hen egg-white lysozyme (HEWL) and Plasmodium falciparum glutathione S-transferase (PfGST) were monitored using the ISS Light Microscopy Module (LMM). Experiments were performed applying the liquid–liquid counter diffusion crystallization method using rectangular, optically transparent capillaries. To analyze the quantity of impurity incorporated into growing crystals, stable fluorescently labeled protein aggregates were prepared and subsequently added at different percent concentrations to nonlabeled monomeric protein suspensions. For HEWL, a covalent cross-linked HEWL dimer was fluorescently labeled, and for PfGST, a stable tetramer was prepared. Crystallization solutions containing different protein aggregate ratios were prepared. The frozen samples were launched on 19.02.2017 via SpaceX-10 mission and immediately transferred to a -80°C freezer on the ISS. Two series of crystallization experiments were performed on ISS, one during 26.02.2017 to 10.03.2017 and a second during 16.06.2017 to 23.06.2017. A comparison of crystal growth rate and size showed different calculated average growth rates as well as different dimensions for crystals growing in different positions along the capillary. The effect of macromolecular mass transport on crystal growth in microgravity was experimentally calculated. In parallel, the percentage of incorporated fluorescent aggregate into the crystals was monitored utilizing the fluorescent LMM and ground-based fluorescent microscopes.

Open access