35^th International Conference and Expo on Nanosciences and Nanotechnology June 05-06, 2023 Madrid, Spain

Biography:

Sudip Chatterjee is presently working as the Associate Professor of Physics in The Swami Vivekananda University, India. He did his Ph.D. from Jadavpur University, India on some electronic transport properties of nano materials and continued his post-doctoral research at TuDelft, The Netherlands. He had worked as the Assistant Professor in The Sikkim Manipal University, India and IFHE University. He has a total teaching and research experience of 18 years. Presently number of research projects has been continuing under his guidance.

Abstract:

The most extensively studied SL is the one consisting of alternate layers of GaAs and Ga1-xAlxAs, owing to its fabrication. The GaAs layers form the quantum wells and the Ga1-xAlxAs layers form the potential barriers. We wish to note that, the afore mentioned SLS have been proposed with the assumption that the interfaces between the layers are sharply defined with zero thicknesses so as to be devoid of any interface effects. As the potential form changes from a well (barrier) to a barrier (well), an intermediate potential region exists for the electrons. Thus the influence of the finite thickness of the interface on the carrier dispersion law becomes very important since, the carrier energy spectrum governs all the transport properties. In this paper, we shall investigate the DMR for the most interesting case which occurs in QDSLs of graded interfaces and compare the same with that of the constituent materials by formulating the respective one dimensional electron dispersion laws. The Einstein relation occupies a singular position in the whole field of nanotechnology. The diffusion constant (A quantity very useful for device analysis but whose exact experimental determination is rather difficult) can be derived from this relation if one knows experimental values of the mobility. In addition, it is more accurate than any of the individual relations for the diffusivity or the mobility, which are two widely used quantities in carrier transport of nano devices. It is well known from the fundamental works of Landsberg that the Einstein relation in degenerate materials is essentially determined by the energy band structures. It has, therefore, different values in different materials and varies with electron concentration, with the magnitude of the reciprocal quantizing magnetic field under magnetic quantization and with the quantizing electric field as in inversion layers having various carrier energy spectra.

Some of the significant features which have immersed from the studies are a) the ratio increases monotonically with electron concentration in bulk semiconductors: b) The nature of the variations is significantly affected by the band non parabolicity: c) The ratio increases with the magnitude of the quantizing electric field in inversion layers : d) The ratio oscillates with the inverse quantizing magnetic field under magnetic quantization due to the SdH effect : e) The ratio exhibits composite oscillations in quantum confined structures having different dispersion relations. The above characteristics are considered as theoretical predictions and no experimental results are available, to the knowledge of the authors in support of the prediction of materials having degenerate electron concentration. The lack of experimental results emanates from the difficulty of the measurement of the diffusion constant D for degenerate materials.

Key words: SLS, QDSL, DMR.

Biography:

Osman Adiguzel graduated from Department of Physics, Ankara University, Turkey in 1974 and received PhD- degree from Dicle University, Diyarbakir-Turkey. He has studied at Surrey University, Guildford, UK, as a post-doctoral research scientist in 1986-1987, and studied were focused on shape memory effect in shape memory alloys. He worked as research assistant, 1975-80, at Dicle University and shifted to Firat University, Elazig, Turkey in 1980. He became professor in 1996, and he has been retired on November 28, 2019, due to the age limit of 67, following academic life of 45 years. He supervised 5 PhD- theses and 3 M. Sc- theses and published over 80 papers in international and national journals; He joined over 120 conferences and symposia in international and national level as participant, invited speaker or keynote speaker with contributions of oral or poster. He served the program chair or conference chair/co-chair in some of these activities. In particular, he joined in last six years (2014 - 2019) over 60 conferences as Keynote Speaker and Conference Co-Chair organized by different companies. Also, he joined over 120 online conferences in the same way in pandemic period of 2020-2022. Dr. Adiguzel served his directorate of Graduate School of Natural and Applied Sciences, Firat University, in 1999-2004. He received a certificate awarded to him and his experimental group in recognition of significant contribution of 2 patterns to the Powder Diffraction File – Release 2000. The ICDD (International Centre for Diffraction Data) also appreciates cooperation of his group and interest in Powder Diffraction File.

Abstract:

Shape memory alloys take place in advanced smart materials, by exhibiting a peculiar property called shape memory effect, which is characterized by the recoverability of two certain shapes of material at different conditions. These alloys have dual characteristics called thermoelasticity and superelasticity, from viewpoint of memory behavior. Shape memory effect is initiated with thermomechanical processes on cooling and deformation and performed thermally on heating and cooling, with which shape of materials cycles between original and deformed shapes in reversible way in bulk level. Therefore, this behavior can be called thermoelasticity. Superelasticity is performed with stressing and releasing the material in elasticity limit at a constant temperature in the parent phase region, and material recovers the original shape upon releasing. Superelasticity exhibits ordinary elastic material behavior, but it is performed in non-linear way; loading and unloading paths are different at the stress-strain diagram, and hysteresis loop refers to energy dissipation. These phenomena are result of crystallographic transformations called martensitic transformation.

Thermoelasticity is governed by the thermal and stress induced martensitic transformations. Thermal induced martensitic transformation occurs on cooling with the cooperative movements of atoms in <110 > -type directions on the {110} - type planes of austenite matrix and ordered parent phase structures turn into twinned martensite structures along with lattice twinning reactions. The twinned structures turn into detwinned structures, by means of stress induced martensitic transformation with deformation. Superelasticity is also governed by stress induced martensitic transformation and ordered parent phase structures turn into detwinned martensite structures with stressing.

On heating after these treatments, detwinned martensite structures turn into the ordered parent phase structures, by means reverse austenitic transformation. Twinned structures are result of lattive invariant shears  on {110} - type planes of austenite matrix. Atomic movements are confined to the nearest atom distance, and these transformations are diffusionless transformations. Superelasticity is also result of stress induced martensitic transformation, and ordered parent phase structures turn into the detwinned martensite structures with  stressing.  Lattice twinning and detwinning reactions play important role at martensitic transformations. These alloys are functional materials with these properties, and used in many fields, from biomedical to the building industry.

Copper based alloys exhibit this property in metastable beta-phase region, which has bcc based structures at the parent phase field. Lattice invariant shear twinningis not uniform in these alloys and cause the formation of complex layered structures, depending on the stacking sequences on the close-packed planes of the ordered lattice, like 3R, 9R and 18R depending on the stacking sequences. Periodicity and unit cell is completed through 18 layers in 18R structures.

In the present contribution; x-ray and electron diffraction studies were carried out on two solution treated copper based CuZnAl and CuAlMn alloys. Electron and x-ray diffraction exhibit super lattice reflections. Specimens of these alloys were aged at room temperature, and a series of x-ray diffractions were taken at different stages of aging at room temperature in a long-term interval. X-Ray diffraction profiles taken from the aged specimens in martensitic conditions reveal that crystal structures of alloys chance in diffusive manner, and this result refers to the stabilization.

Keywords: Shape memory effect, martensitic transformation, thermoelasticity, superelasticity, lattice twinning detwinning.  

Biography:

Djendel Abderrazak has a baccalaureate in Mathematics specialty, besides that he has a bachelor's degree and a master's degree in Analytical Chemistry. For the moment, I am PhD student between the University of Bejaia (Algeria) and Aix Marseille University (France) within the framework of a scientific collaboration; I am interested to study the modifications of materials surfaces for dental and orthopedic applications.

Abstract:

Titanium and its alloys are widely used as biomaterials such as human body implants [1]. Their good biocompatibility is correlated with a natural layer of titanium oxide (TiO2) that presents anti-corrosion properties [2]. Since this layer is very thin (in the nanometers range), adherent and smooth, it cannot resist long time loads as required for orthopedic implants [3] and do not allow adequate cell adhesion [4]. Surface improvements are then necessary. In that way, electrochemical anodization is a simple method to achieve these objectives: create a rough surface for better cell development and a dense barrier layer to improve corrosion resistance [6]. We present here electrochemical surface modifications on Ti-6Al-4V alloy (Titanium grade 5) that consisting of different TiO2 layers that can be monitored as a function of the electrochemical conditions used: either compact (C), or nanotubular (N), or combined (NC). Several characterizations were recorded such as: morphological, chemical and structural analyses, corrosion tests in physiological conditions, adhesion measurements, hydrophilicity and cell growth quantification. Comparison of the results allowed us to determine the best coating from both corrosion and bioactive (perspectives) point of view.

Keywords: Bones, Ti-6Al-4V, Nanotubes, Corrosion, Adhesion, Cell development.

Recent Publications:

1. D.R.N. Correa, F.B. Vicente, T.A.G. Donato, V.E. Arana-Chavez, M.A.R. Buzalaf, C.R. Grandini (2014), The effect of the solute on the structure, selected mechanical properties, and biocompatibility of Ti-Zr system alloys for dental applications, Mater. Sci. Eng. C. 34:354–359

2. K.L. Ong, J. Schmier, K. Zhao, F. Mowat, E. Lau, S.M. Kurtz (2009), Primary and Revision Arthroplasty Surgery Caseloads in the United States from 1990 to 2004, J. Arthroplasty 24:195–203.

3. E.M. Szesz, B.L. Pereira, N.K. Kuromoto, C.E.B. Marino, G.B. De Souza, P. Soares (2013), Electrochemical and morphological analyses on the titanium surface modified by shot blasting and anodic oxidation processes, Thin Solid Films 528:163–166.

4. M. Sarraf, A. Dabbagh, B. Abdul Razak, R. Mahmoodian, B. Nasiri-Tabrizi, H.R.M. Hosseini, S. Saber-Samandari, N.H. Abu Kasim, H. Abdullah, N.L. Sukiman (2018), Highly-ordered TiO2 nanotubes decorated with Ag2O nanoparticles for improved biofunctionality of Ti6Al4V, Surf. Coatings Technol. 349:1008–1017.

5. J. Qin, Z. Cao, H. Li, Z. Su (2021), Formation of anodic TiO2 nanotube arrays with ultra-small pore size, Surf. Coatings Technol. 405:126661.

6. D. Regonini, C.R. Bowen, A. Jaroenworaluck, R. Stevens (2013), A review of growth mechanism, structure and crystallinity of anodized TiO2 nanotubes, Mater. Sci. Eng. R Reports. 74:377–406.

Biography:

Mirza Muhammad Faran Ashraf Baig research work mainly focuses on the construction and function of DNA nanomachines, which are cutting-edge and challenging topics. He designed and constructed unique DNA motifs using a short circular DNA nanotechnology technique and functionalized these probes with fluorophores, gold nanoparticles, small molecular drugs and peptide ligands. To achieve plasmon resonance effects, he achieved nano-specific precision in organizing plasmonic nanoparticles on the nano DNA frameworks. His work on the DNA nanomachines provided an efficient fluorescence resonance energy transfer mechanism that realizes the bio-imaging, detection of biological events and functions of the biomolecules. He has also been working on multilayered hybrid magnetic nanoparticles for applications in nanomedicine for the last three years.

Abstract:

Magnetic Gold Nano-Particles (mGNP) have become a great interest of research for nanomaterial scientists because of their significant magnetic and plasmonic properties applicable in biomedical applications. Various synthetic approaches and surface modification techniques have been used for mGNP including the most common being the co-precipitation, thermal decomposition and micro-emulsion methods in addition to the Brust Schiffrin technique, which involves the reduction of metal precursors in a two-phase system (water and toluene) in the presence of alkanethiol. The hybrid magnetic–plasmonic nanoparticles based on iron core and gold shell are being considered as potential theragnostic agents. Herein, in addition to future works, we will discuss recent developments for synthesis and surface modification of mGNP with their applications in modern biomedical science such as drug and gene delivery, bio-imaging, bio-sensing and neuro-regenerative disorders. I shall also discuss the techniques based on my research related to the biological applications of mGNP.

Keywords: Nanohybrids, Magnetic gold nanoparticles, Nanocomposites, Surface functionalization, Core-shell nanocomposites, Magnetic-plasmonic nanoparticles, biological applications.

Biography:

Surabhi Sharma is currently student at Madan Mohan Malaviya University of Technology Gorakhpur, Uttar Pradesh, India.

Abstract:

The synthesis of metal oxide semiconductor nanoparticles has attracted much attention in recent past. Nanoparticles are broadly used in solar energy conversion, catalysis, varistors, gas sensors and non-linear optics, etc. Owing to the large band gap zinc oxide nanoparticles are widely used in numerous applications. Zinc oxide nanoparticles have a wide band gap of approximately 3.3 eV. In this paper, we have reported synthesis and characterization of flower like structures of ZnO nanoparticles synthesized by the green routes. In this zinc acetate dehydrate [Zn (CH₃COO) ₂. 2H₂O] and aqueous extract of Dahlia pinnata leaves are used. Deionized water used as a solvent. The unique morphology of ZnO NPs flower like structures enhances its sensing properties in comparison to the spherical ones. The obtained ZnO nanoparticles are characterized by the UV-vis-nir spectroscopy, X-Ray Diffraction (XRD), Fourier Transform Infrared Microscopy (FTIR), Scanning Electron Microscope (SEM) analysis.

Keyword: ZnO NPs, Dahelia pinnata, XRD, SEM, FTIR, UV-vis-nir.