European
Physics Conference 2018

Nikolai Perov works in Lomonosov MSU since 1977, PhD in magnetism - 1986, DrSc in magnetism - 2009, visiting experience - Tohoku university, Toyohashi university of technology, National University of Singapore, Duisburg-Essen university. Nowadays he is the head of the magnetism department of Lomonosov MSU. Research interests are in investigation of magnetic field.

We present the results of numerical simulation of magnetodielectric effect (MDE) in magnetorheological elastomers (MRE) – the change of capacity of plane capacitor filled with magnetic elastomer and placed under the external magnetic field. The computer model of effect is based on the assumption about the displacement of magnetic particles inside the elastic matrix under the external magnetic field and the formation of chain-like structures. Such displacement of metallic particles between the planes of capacitor leads to the change of capacity, which can be considered as a change of effective dielectric permittivity of elastomer caused by magnetic field (magnetodielectric effect).

The developed model resulted in perfect qualitative agreement with all experimental data obtained earlier for Fe-based elastomers. The proposed model is useful to study these novel functional materials, analyze the features of magnetodielectric effect and predict the optimal composition of magnetorheological elastomers for further profound experimental study.

In this work we simulated MDE for series of samples varying with concentration of magnetic filler, size and space distribution of particles, elastic properties of matrix. We have found that the effect tends to saturation and has hysteretic feature due to the elastic response of matrix. The influence of orientation of magnetic field and capacitor plane was studied as well, the change of sign of the effect for parallel and perpendicular orientation was observed as well.

Sergio Lechago received the Engineering Master’s Degree in Telecommunications (2014) from the Universitat Politècnica de València (UPV), Spain, and is currently finishing his PhD on Silicon photonic nanoantennas. Sergio has thorough experience in the design and characterization of Si photonic devices, including wireless on-chip systems as well as nanolithographic fabrication techniques carried out at clean rooms. Sergio is collaborating in several FP7 and H2020 European projects, including FP7-ICT-PHOXTROT and the H2020-FET-HPC EXANEST. Sergio has authored or co-authored publications in relevant international conferences and high impact journals (Nature’s Light Science and Applications, Optics Express, Optics letters or Journal of optics).

Photonic integrated circuits (PICs) promise to open new avenues in high-performance computing, biosensing or optical beamforming, amongst others. Current PICs rely on the use of guided interconnects, hampering the creation of flexible and reconfigurable networks-on-a-chip and preventing the far-field light-matter interaction for many sensing applications. Here we propose a novel on-chip silicon antenna that, in contrast to their plasmonic counterparts, exhibits an ultra-high directivity (>100), low losses, low reflections and a broadband response. These nanoantennas are the main building blocks of a new wireless photonic platform that solves the aforementioned problems, widening the range of achievable integrated photonic functionalities. The studied antennas consist of inverted-taper silicon strips with additional structures behaving as directors. They were modelled via Huygens’ Principle and fabricated over silicon-on-insulator wafers, assuring CMOS compatibility. As main applications we experimentally demonstrate the first on-chip wireless data-streaming link, with a speed as high as 160 Gbit•s-1 over a distance of 100 µm, an electrically controlled antenna-array beam-steering device and an ultra-compact (with a footprint several orders of magnitude smaller than previous versions) lab-on-a-chip antenna-based microflow cytometer able to classify microparticles of several sizes. This work shows the potential of the proposed wireless platform, providing much more flexible and reconfigurable optical interconnects and architectures as well as boosting new applications in the field of nanoscale applications and photonic integrated circuitry.

Kenneth Fontánez graduated from an associate degree in Mechanical Engineering. He is a research student in Universidad del Turabo in Puerto Rico currently pursuing a bachelor’s degree in chemistry with a record of 3 different investigations as well as an internship in Universidad Autonoma de Madrid (UAM).

Detection of ionizing radiation is crucial in different fields including energy, national security, biological and nuclear research, and other applications. In general, the systems for the detection of ionizing radiation usually have one or several of the following drawbacks: incapability to produce stable signals, expensive and complicated manufacturing processes, operation at low or very low temperatures, low sensitivity or even voluminous size, as is the case of Geiger counters. Single Walled Carbon Nanotubes (SWNTs) have attracted much interest for the design of advanced nanodevices, due to its excellent mechanical, optical, thermal properties and electrical conductivity. Among the possible applications, these materials can be successfully used as efficient ionizing radiation sensors. For this purpose, the critical steps in the design and fabrication of devices are focused on the growth of SWNTs into controlled architectures and onto appropriate substrates. In this research we report a method for the treatment of the silicon substrates with TiN and a mixture of Co and Mo salts as catalyst precursor for the synthesis of carbon nanotubes. XPS and AFM results show an appropriate distribution of the catalyst precursors on the Si surface. SWNTs obtained by this procedure have been used for the manufacture of a sensor prototype. As a result, this research shows the first data obtained when the prototype is exposed to increasing doses of radiation.

He is an Independent researcher and Research scholar at Ronin Institute. A detail of my work and about my planning could be overviewed here at https://www.researchgate.net/profile/Bishal_Banjara as well in http://ronininstitute.org/research-scholars/bishal-banjara/.

The fundamental nature of intrinsic inertia is interrogated within the conventional basis, relating the Landau's (1976) extraction of Galilean frame with no ambiguity made on Machian type.

Prof. Dr. Igor Kadenko has completed his PhD from Kiev State University, USSR/Ukraine and lately defended his doctoral thesis in Institute for Nuclear Researches, National Academy of Sciences of Ukraine. He is the Director of International Nuclear Safety Center of Ukraine and Head of Department of Nuclear Physics and Engineering of Taras Shevchenko National University of Kyiv, a leading educational organization in Ukraine. He has published more than 160 papers in reputed journals in fields of nuclear physics, high energy physics and nuclear engineering.

This paper deals with consideration of a new nuclear reaction type on 159Tb with a bound dineutron in the outgoing channel. The dineutron as a particle consisting of the two bound neutrons has been the target of scientific hunt for 70 years, since the very first publication of Colby and Little in Phys. Rev. in 1946. For decades a neutron-only nucleus was considered physically impossible. This paper presents results of experiments that report on the first statistically significant observation of an exotic state of nucleons, the long-sought dineutron, with conclusion that emission of the dineutron takes place in (p,2n+n) and (n,2n) nuclear reactions on 159Tb and represents a new type nuclear reaction in the output channel. The explanation of these experimental results is based on theoretical paper of Migdal from 1972 when the dineutron was predicted theoretically as a bound state of the two neutrons emitted from the nucleus through the mechanism of binding the two neutrons in one single particle near the surface, but outside a heavy nucleus such as 157Dy or 158Tb. Such a formation is possible due to the strong nuclear force from a heavy nucleus holding the two neutrons in close proximity for certain time. The dineutron is difficult to acquire and detect; therefore this problem has been solved by identifying a residual nucleus in the output channel of corresponding nuclear reaction. The dineutron may be only the very first evidence for existence of low nucleon bound systems composed of two or even three identical nucleons.

Wei Chen completed his Ph.D and he working as a associate professor in Fudan University. His research interests are Philosophy of logic, philosophy of language; legal logic; argumentation theory and critical thinking; analytical Marxism; philosophy of the internet.

Near-interface colloidal monolayers have often been used as model systems for research on hydrodynamics in biophysics and microfluidic systems. Using optical microscopy and multiparticle tracking techniques, the correlated diffusion of particles is experimentally measured in colloidal monolayers near a water-air interface. It is found that the characteristic lengths χ_∥ and χ_⊥ of such a colloidal monolayer are anisotropic in these two perpendicular directions. The former (χ_∥) is equal to the Saffman length of the monolayer and reflects the continuous nature of the system in the longitudinal direction. The latter (χ_⊥) is a function of both the Saffman length and the radius of the colloids and reflects the discrete nature of the system in the transverse direction. This discovery demonstrates that the hydrodynamics intrinsically follow different rules in these two directions in this system.

Keywords: Hydrodynamics, liquid interface, colloid, characteristic lengths.

  I have investigated plasma phenomena in strong gravitational field around black holes and neutron stars. I was awarded the DSc degree from Nagoya University on my research on general relativistic magnetohydrodynamic accretion onto rotating black holes. After that, I studied the gamma-ray emissions from pulsar magnetospheres by developing a numerical code that solves the set of stationary Maxwell-Boltzmann equations in National astronomical observatory in Japan, NASA/GSFC in the USA, MPI-Kernphysik in Heidelberg, Germany, and ASIAA in Taiwan. I applied the same method to black-hole magnetospheres and am investigating very high energy emissions from the direct vicinity of the event horizon. 

Imaging Atmospheric Cherenkov Telescopes have revealed more than 100 TeV sources along the Galactic Plane, around 45 per cent of them remain unidentified.  However, radio observations revealed that dense molecular clumps are associated with 67 per cent of 18 unidentified TeV sources.  In this talk, we propose that an electron-positron magnetospheric accelerator emits detectable TeV gamma-rays when a rapidly rotating black hole enters a gaseous cloud.  Since the general-relativistic effect plays an essential role in this magnetospheric lepton accelerator scenario, the emissions take place in the direct vicinity of the event horizon, resulting in a point-like gamma-ray image.  We demonstrate that their gamma-ray spectra have two peaks around 0.1 GeV and 0.1 TeV and that the accelerators become most luminous when the mass accretion rate becomes about 0.01 per cent of the Eddington rate.  We compare the results with alternative scenarios such as the cosmic-ray hadron scenario, which predicts an extended morphology of the gamma-ray image with a single power-law photon spectrum from GeV to 100~TeV.

   Dr Adiguzel graduated from Department of Physics, Ankara University, Turkey in 1974 and received PhD- degree from Dicle University, Diyarbakir-Turkey. He studied at Surrey University, Guildford, UK, as a post doctoral research scientist in 1986-1987, and studied on shape memory alloys. He worked as research assistant, 1975-80, at Dicle University and moved to Firat University, Elazig, Turkey in 1980. He became professor in 1996, and he has already been working as professor. He published over 50 papers in international and national journals; He joined over 100 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 four years (2014 - 2017) over 30 conferences as Keynote Speaker and Conference Co-Chair organized by different companies.  He supervised 5 Ph. D and 3 M.Sc- theses. 

  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.

  Shape memory alloys are stimulus responsive materials to the external conditions, and exhibit a peculiar property called shape memory effect, Shape memory effect is initiated by cooling and stressing material, and activated on heating and cooling following the initiated processes. Shape memory behaviour of shape memory materials is evaluated by the structural changes in crystallographic level. Shape memory effect is governed by successive structural transformations; thermal induced and stress induced martensitic transformations, in atomic and crystallographic basis. Thermal induced martensitic transformation occurs with cooperative movements of atoms by means of shear-like mechanism on cooling from parent austenite phase region. Product martensite phase occurs as martensite variants in self-accommodated manner with lattice invariant shears on the {110}-type close packed planes of austenite matrix. Therefore, 24 martensite variants occur in different orientations. Thermal induced martensite occurs as twinned martensite, and the twinned structures turn into detwinned structures by means of stress-induced martensitic transformation by stressing the material in the martensitic condition. Shape memory alloys can be easily deformed through variant reorientation or detwinning process. Therefore, martensite is called soft phase and austenite is also called hard phase. Shape memory effect is activated thermally on heating and cooling after first cooling and stressing processes, this behaviour can be called thermoelasticity.  Shape memory alloys exhibit another property called superelasticity, which occurs by only mechanically stressing and releasing at a constant temperature in parent phase region. This is result of stress induced martensitic transformation, at which stress strain curves follow different ways on heating and releasing. This result refers to energy dissipation. 

    Copper based alloys exhibit this property in metastable β-phase region. Lattice invariant shears are not uniform in these alloys, and the ordered parent phase structures martensitically undergo the non-conventional long-period layered structures on cooling.  The long-period layered structures can be described by different unit cells depending on the stacking sequences on the close-packed planes of the ordered lattice.    In the present contribution, x-ray and electron diffraction studies were carried out on two copper based CuZnAl and CuAlMn alloys. These alloy samples have been heat treated for homogenization in the β-phase fields. X-ray diffraction profiles and electron diffraction patterns reveal that both alloys exhibit super lattice reflections inherited from parent phase due to the displacive character of martensitic transformation. X-ray diffractograms taken in a long time interval show that diffraction angles and intensities of diffraction peaks change with the aging time at room temperature, and this result leads to the rearrangement of atoms in diffusive manner.

The Blood-Brain-Barrier (BBB) is the tight membrane that protects our brain and represents the major hindrance to the use of chemotherapeutic agents for brain tumors. 

Recently it has been showed by in vitro and in vivo studies that the adsorption of apolipoprotein E4 (ApoE4) on lipid nanoparticles (NPs) produces a protein corona that enhances the BBB-crossing, improving brain NP accumulation 3-fold compared to undecorated particles. Therefore, it is possible to increase the ability to cross the BBB for engineered NPs carrying a loose layer of proteins. Nevertheless, the NP-protein corona composition––and, as a consequence, the cellular biological response to the NP––change over time as a consequence of the competition among the plasma proteins once the NP is in the blood stream, as we showed.

In collaboration with experimental groups, we develop a multiscale approach for the study of bio-membranes, proteins, NPs and nanomaterials in aqueous solution oriented to applications to the BBB crossing for oncological treatments. We model the kinetics of NP interaction with proteins ,of proteins with water, and of water with membranes and nanomaterials, with the aim of finding how to optimize the NP-protein corona formation to cross the BBB.

 We will describe our recent results by all-atom simulations and coarse-grained models, e.g. showing that the water-membrane interface has a structural effect at ambient conditions that propagates further than the often-invoked 1 nm length scale and that the translational and rotational dynamics of water molecules is strongly determined by their local distance to the membrane so that we can identify the existence of an interface between the first hydration shell, partially made of hydration water bound to the membrane, and the next shells entirely made of unbound hydration water. These results could drastically affect the kinetics of the protein-corona, determining the fate of NPs during the BBB crossing.