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Structural Parameters of Functional Membranes for Integration in Smart Wearable Materials

Eldessouki M., Aysha T., Ratičáková M., Šašková J., Padil V. V. T., Ibrahim M., Černík M.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 5 (125)

73--78

EN

Smart clothes can be described as textiles that change their behavior under some external factors (stimulants). The response of the smart cloth can be passive (just as a sensor) or active (where a combination of sensing and another reaction takes place). The materials involved in these textiles are crucial for many applications, especially for health related applications where the “wearables” can provide instantaneous monitoring and aid to people with certain disabilities. This work consists of two main parts: First it investigates the different materials used in smart clothing for monitoring the vital activities of the human body (e.g. the breathing rates) with an emphasis on piezoresistive structures as they work sensing elements for mechanical strains. Second this work presents the production of functional membrane samples based on synthesized pyrrolinone ester hydrazone dye with a preliminary investigation of their chemical and geometrical parameters, especially their sensitivity for monitoring the presence of ammonia to function as a smart textile based colorimetric chemosensor.

PL

„Inteligentne” ubrania można opisać jako tekstylia, które reagują pod wpływem czynników zewnętrznych (bodźców). Odpowiedź „inteligentnej” odzieży może być bierna (czujnik) lub czynna (wykrywanie i reakcja). Materiały związane z tymi wyrobami tekstylnymi mają kluczowe znaczenie dla wielu zastosowań, zwłaszcza dla tych związanych ze zdrowiem, gdzie odzież może zapewnić natychmiastowy monitoring i pomoc osobom niepełnosprawnym. Przedstawiona praca składała się z dwóch głównych części: najpierw badano różne materiały stosowane w „inteligentnej” odzieży do monitorowania istotnych czynności organizmu ludzkiego (np. szybkości oddychania), ze szczególnym uwzględnieniem struktur piezorezystancyjnych. W drugiej części pracy przedstawiono wytwarzanie funkcjonalnych membran z zastosowaniem syntetycznego barwnika, zbadano parametry chemiczne i geometryczne, w szczególności wrażliwości na monitorowanie obecności amoniaku w celu zastosowania wyrobu jako chemosensor kolorymetryczny.

2

Increasing of the Mechanical Properties of Friction Stir Welded Joints of 6061 Aluminum Alloy by Introducing Alumina Particles

Tashkandi M. A., Al-Jarrah J. A., Ibrahim M.

Advances in Materials Science

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2017

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Vol. 17, nr 2(52)

29--40

EN

The main aim of this investigation is to produce a welding joint of higher strength than that of base metals. Composite welded joints were produced by friction stir welding process. 6061 aluminum alloy was used as a base metal and alumina particles added to welding zone to form metal matrix composites. The volume fraction of alumina particles incorporated in this study were 2, 4, 6, 8 and 10 vol% were added on both sides of welding line. Also, the alumina particles were pre-mixed with magnesium particles prior being added to the welding zone. Magnesium particles were used to enhance the bonding between the alumina particles and the matrix of 6061 aluminum alloy. Friction stir welded joints containing alumina particles were successfully obtained and it was observed that the strength of these joints was better than that of base metal. Experimental results showed that incorporating volume fraction of alumina particles up to 6 vol% into the welding zone led to higher strength of the composite welded joints as compared to plain welded joints.

3

Synthesis and Structural Characterization of Self-Assembly Products Containing [Fe(CN)6]4- Building Blocks with Cationic {R3Sn}+ Fragments in the Absence or Presence of a Bidentate Uncharged LIgand {2L}

Ibrahim M., Morgan A., Mecky A., Etaiw S.

Polish Journal of Chemistry

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2004

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Vol. 78 / nr 2

173-185

EN

Spontaneous self-assembly of [Fe(CN)6]4- andR3Sn+ ions (R = Me, n-Bu or Ph) in the absence or presence of uncharged bidentate ligands (such as dioxane (diox), methylpyrazine (Mepyz), or 4,4_-bipyridine (bpy)) affords white precipitates. The products with the general composition [(R3Sn)4Fe(CN)6_2H2O_2L]; 2L = diox, Mepyz or bpy, have been obtained as host-guest polymeric architecture. The new compounds have been compared with their hydrated systems [(Me3Sn)4Fe(CN)6_xH2O]; x = 2 or 4 and with the water-free [(Me3Sn)4Fe(CN)6]. Results of extensive spectroscopic investigations (IR studies and X-ray powder diffractometry) suggest that the architecture of the novel host-guest systems involve three-dimensional networks, notably different from those of their parent system (containing fourH2Omolecules). These compounds show no ion-exchange activity towards NH4 + cations and are affected by moderate temperature. Also, these 3D-host-guest polymeric systems exhibit a high sensitivity to pH of the media.

4

New Molecular Composites: Pyridine Derivatives as Guest Molecules Encapsulated within the Cavities of the Three-Dimensional Supramolecular Complexes - [(R3Sn)3Fe(CN)6]n, R=Ph or n-Bu

Ibrahim M.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 10

1417-1425

EN

Spontaneous self assembly reaction of [-Fe(CN)6]3- building blocks and R3Sn+ ions (R = alkyl or aryl) affords three-dimensional (3D) supramolecular [(R3Sn)3Fe(CN)6]n products, which were confirmed by different spectral data. The architecture of these supramolecular complexes involve guest-free cyanide-bridged 3D neutral networks. They are composed of nearly plannar R3Sn+ units, linked together with slightly distorted octahedral building blocks [-Fe(CN)6]3- through the cyanide N atoms. Pyridine compounds, acting as guest donors, have been successfully encapsulated within the expandable wide cavities of the 3D-supramolecular complexes by tribochemical reactions. This produces novel charge transfer molecular composites. The properties of the resulting molecular composites were investigated by elemental analyses, IR, UV-visible, X-ray powder diffraction, EPR and magnetic moments. The interesting feature of these molecular composites are their semiconductive properties.