Biography:

Miroslav Vlcek completed his PhD from Institute of Chemical Technology, Pardubice, Czechoslovakia in 1987. Since 1998, he has been an Associate Professor and since 2005, he has been a Professor at University of Pardubice, Czech Republic. In 2003-2004, he was working as Visiting Professor at Lehigh University, PA, USA. Presently, he is the Director of Center of Materials and Nanotechnologies at University of Pardubice. He has published more than 120 papers. His research is focused on “Photoinduced structural changes in chalcogenide glasses and application of this phenomena in fields such as photonics, diffractive optics and high resolution lithography”.

Abstract:

Chalcogenide glasses (CHGs) are very promising materials for many photonic applications due to their unique properties and functionalities. They posess for example wide IR transmission window, high non-linearity of optical properties, high refractive index and many of them are sensitive to bandgap or UV light, or electron and ion beams. In adition, their composition can be locally modified by exploiting radiation induced diffusion and dissolution of suitable metals (e.g., Ag, Zn). All these structural/compositional changes result in selective wet or dry etching which allows ChGs surface structuring on micro and/or even nanoscale. Lower rigidity and lower softening temperatures in comparison with classical oxide glasses allow their surface to be corrugated by direct laser writing method or by embossing. In this paper, we review methods of CHGs micro and nanostructuring and demonstrate applications of CHGs thin films prepared by vacuum based or solution based deposition techniques (such as spin-coating) in high-resolution UV, electron lithography and as materials for fabrication of diffractive elements for VIS and IR spectral region.

Biography:

Tilahun Ayane Debele received his BSc degree in Applied Chemistry at Ambo University and his MSc degree in Medical Biochemistry from Addis Ababa University, School of medicine, Ethiopia. He is currently a PhD student in Graduate studies of Applied Science and Technology at National Taiwan University of Science and Technology, concentrating on using nanoparticles as photosensitizer delivery in photodynamic therapy of cancer under supervision of Professor Hsieh-Chih Tsai. He has published five papers in reputed journals.

Abstract:

Herein, we synthesized and characterized novel bioreducible heparin polyethyleneimine (HPC) nanogels consisted of heparin, branched polyethyleneimine (PEI) and L-cysteine. ¹H-NMR and FTIR analysis confirmed the formation of HPC nanogels while TEM and dynamic light scattering revealed uniform spherical nanoparticles with average diameter of <200 nm. Zinc phthalocyanine (ZnPC) was encapsulated via the dialysis method and the drug is released in vitro from disulfide-containing HPC nanogels in a redox-sensitive manner. Additionally, HPC nanogels possess bright blue fluorescence which eliminates the use of additional probing agent in image-guided drug delivery. Moreover, singlet oxygen detection revealed that nanogels prevented ZnPc aggregation thus enhancing ¹O₂ generation and photodynamic therapy (PDT) efficacy. These results showed that disulfide crosslinked HPC nanogels are promising vehicles for stimulated photosensitizer delivery in advanced PDT.  

Biography:

Salma Fouad is an MSc holder in Nano-chemistry from American University in Cairo (AUC). She first graduated from Faculty of Science, Ain Shams University in 2010. In spring 2012, she joined the American University, as a chemistry Master student, and got her degree in fall 2015.

She worked as teaching assistant in the chemistry department, AUC, from fall 2012-till spring 2015. In 2013, she joined Zewail City for Science and Technology where she worked as both teaching assistant in the chemistry department, and research assistant in the material science department, nanotechnology center. She was awarded the University fellowship and the thesis grant from the School of Science and Engineering, AUC. Also she was awarded the graduate student of honor for her academic achievement throughout her graduate study.

Abstract:

In this study, an interactive electrospun nanofibrous scaffolds, based on two biopolymers, Polylactic acid (PLA) and Cellulose acetate (CA), was prepared.Thymoquinone (TQ), was incorporated into the electrospun fibers. TQ is the active ingredient of Nigella sativa, known for its antibacterial properties and ability to promote wound healing. The potentiality of the prepared scaffolds, as an interactive wound dressing, has been investigated including, swelling behavior, water vapor permeability and porosity.  TQ- release profile was examined at the physiological pH (7.4) and temperature (37^οC). The antimicrobial efficiency of the scaffolds against gram negative and gram positive bacteria were determined by the agar diffusion assay. The interaction between fibroblasts and the prepared scaffolds such as viability, proliferation, and attachment were characterized. TQ-loaded PLA: CA scaffolds showed burst TQ release after 24 h, compared with TQ-loaded PLA scaffolds, followed by a sustained release rate. The presence of CA in the scaffolds improved its hydrophilicity, and water uptake capacity. Furthermore, it created a moist environment for the wound, which can accelerate wound recovery.The TQ-loaded PLA: CA nanocomposite also showed a significant antibacterial activity against both gram positive and gram negative bacteria. Furthermore, the nanocomposite scaffolds enhanced cell proliferation and attachment, as compared to TQ-loaded PLA nanofibers.  A preliminary in vivo study performed on mice skin wound models demonstrated that TQ-loaded PLA: CA (7:3) scaffolds significantly accelerated the wound healing process by promoting angiogenesis, increasing re-epithelialization and controlling granulation tissue formation. Our results suggest that TQ-loaded PLA: CA nanocomposite could be an ideal biomaterial for wound dressing.

Biography:

Karina Bugan Debs has concluded her Under-graduate course in Chemistry at Universidade Federal de São Paulo (Brazil) in 2013. During her under-graduation, she was University Monitor for one year, worked with scientific research and also was Intern in an Environmental Company (CETESB) for one and a half year. Currently, she is enrolled in an Academic Master Program, named Science and Technology for Sustainability at the same university.

Abstract:

Oil spills are a relevant concern because they can potentially impact the whole ecosystem. Finding materials that are able to remove oil from aqueous solution and remediate oil spills is, therefore, a necessity. In this study, yeast biomass from alcohol industry and magnetite nanoparticles are combined to form a hybrid material, which has magnetic properties. The magnetite nanoparticles were synthesized by co-precipitation of FeCl₂.4H₂O and FeCl₃.6H₂O. The hybrid material and magnetite nanoparticles were characterized using XRD, FTIR, SEM and VSM; these techniques confirmed the formation of the hybrid material. The material was tested for two oil removals (motor used/new oil) at different temperatures (5°C, 25°C and 45°C). In the used oil study, the temperature did not contribute with the removal capacity. The experiments showed an excellent oil removal capacity and the results were also compared to magnetite nanoparticles itself. The removal capacity varied from 1338 to 3272 g/kg of material, being the best result obtained at 5°C by the magnetite nanoparticle. Possibly, it occurs because the nanoparticles have a higher magnetic constant than the hybrid material, getting more oil stucked by the magnetic field.

Biography:

Ahmad Rafiq has completed his MS from King Fahd University of Petroleum and Minerals, Saudi Arabia. He has published two papers in reputed journals and presented in a number of international conferences.

Abstract:

This study presents the potential of hybrid glass fiber reinforced epoxy (GFRE) clay nanocomposites as impact resistant laminated composites in high temperature water laden environment. Electrical grade-corrosion resistant (E-CR) glass fiber mats were used to prepare the hybrid GFRE nanocomposites by employing hand layup and hot pressing techniques. The nanocomposite matrix was synthesized by high shear mixing using one to five wt% loading of I.30E and immersed in water at 23°C and 80°C. A two-step water uptake behavior was observed which showed lowest weight gain for five wt% samples. Addition of nanoclay showed improvement in wateruptake resistance but reduced with subsequent clay addition due to processing difficulties at higher clay loadings as confirmed by SEM analysis. The rate of diffusion for 80°C samples was more than twice that of room temperature samples. The most reduction in flexural strength and modulus was seen for five wt% samples which reached upto 55% and 12%. The combined effect of high temperature and plasticizing effect of water caused significant decrease in flexural properties. Addition of nanoclay showed 16% improvement in flexural strength for 80°C which was the highest for 1.5 wt%.

Biography:

Ahmad Rafiq has completed his MS from King Fahd University of Petroleum and Minerals, Saudi Arabia. He has published two papers in reputed journals and presented in a number of international conferences.

Abstract:

This study presents the potential of hybrid glass fiber reinforced epoxy (GFRE) clay nanocomposites as impact resistant laminated composites in high temperature water laden environment. Electrical grade-corrosion resistant (E-CR) glass fiber mats were used to prepare the hybrid GFRE nanocomposites by employing hand layup and hot pressing techniques. The nanocomposite matrix was synthesized by high shear mixing using one to five wt% loading of I.30E and immersed in water at 23°C and 80°C. A two-step water uptake behavior was observed which showed lowest weight gain for five wt% samples. Addition of nanoclay showed improvement in wateruptake resistance but reduced with subsequent clay addition due to processing difficulties at higher clay loadings as confirmed by SEM analysis. The rate of diffusion for 80°C samples was more than twice that of room temperature samples. The most reduction in flexural strength and modulus was seen for five wt% samples which reached upto 55% and 12%. The combined effect of high temperature and plasticizing effect of water caused significant decrease in flexural properties. Addition of nanoclay showed 16% improvement in flexural strength for 80°C which was the highest for 1.5 wt%.

Biography:

Park Joung-Man completed his PhD from Washington State University and Post-doctoral from Cornell University. He has published more than 130 papers on “Interfacial properties of composite materials and NDE”. He has been Co-Editors-in-Chief of Advanced Composite Materials and Adjunct Professor in Department of Mechanical Engineering, University of Utah since 2004. He is currently President of Korea Society of Composite Materials (KSCM) and Vice President of Korea Society of Adhesion and Interface (KSAI).

Abstract:

Carbon fibers are used as sensing elements in CFRP due to their electrical conductivity. In some more advanced studies, in CRFP, the carbon fibers were used for both strain sensing and damage sensing. The basic theory, in such studies, was that the movement of carbon fiber could be detected by ER (ER) measurement. This work evaluated the potential use of carbon fiber/polypropylene-polyamide (CF/PP-PA) composites in thermoplastic automobile applications. Two dimensional electrical resistance (2D ER) mapping was used to sense and predict damages. The extent of random dispersion of carbon fibers (CF) in PP-PA matrix was evaluated using 2D ER mapping contour charts. ER data collected at nine different positions was used to evaluate dispersion and micro-damages. The uniformity of dispersion of CF in fractured surfaces was observed for comparison. Pyrolyzed specimens were used to measure CF amount in each part and compared with 2D ER mapping. The differences in ER for tensile and compressive stresses were compared to explore their usage for real time monitoring and sensing of damages. The observation of the fractured surfaces exhibited an acceptable consistency with 2D ER results. Ultimately 2D ER mapping should be useful for evaluating and predicting damages in CF/PP-PA composites under various loading conditions. This may have some very significant practical importance. It may point the way to use quick easy tests to screen and predict other mechanical failure behaviors for composites of different materials and/or processes. Perhaps a simple 2D ER mapping test might be used to predict and select good candidate materials, surface processing techniques for various high strength composite applications.