Institute Of Applied Physics Research Articles

A SIMPLE SOURCE OF METAL AND GAS IONS FOR ION BEAM TECHNOLOGICAL INSTALLATIONS

At the stand of the Institute of Applied Physics of the National Academy of Sciences of Ukraine, a small-sized spattering source of metal and gas ions was developed, manufactured and tested. Ionization of sputtered atoms occurs by fast oscillating electrons in a longitudinal magnetic field. A beam containing ions of plasma-forming gas and metal is output through an emission hole in the anticathode. The source has high ion current stability, is easy to maintain, and can generate ions from any conductive solid. Modeling and manufacturing of an ion-optical system for this source, which is part of the injector of the implanter of the Institute of Applied Physics of the National Academy of Sciences of Ukraine, was carried out.

Radiofrequency Diagnostic of the Decaying Plasma in the “Gigantic” Coaxial Line at the Large Plasma Device

At the large-scale Krot facility (Gaponov-Grekhov Institute of Applied Physics of the Russian Academy of Sciences), a new device was developed for laboratory simulations of the effects of the interaction of ultrawideband electromagnetic pulses with the partially ionized atmosphere and ionosphere: the “gigantic” coaxial line with a length of 10 m and diameter of 1.4 m that is filled by the decaying plasma of the inductive discharge. Two radiofrequency methods of wave diagnostics used in the device are described, the cutoff method and the wave interferometer, which can be used to determine the electron density of the plasma in the line in a wide range of values, Ne = 107–1011 cm–3. The measurement results are compared with the values obtained by the contact diagnostic, a probe with a microwave resonator. The interferometric method is implemented taking into account the nonuniform distribution of plasma density both along and across the transmission line, which, in the working range of pulsed and continuous diagnostic signals, is an oversized waveguide. The specific features of application and the limitations of the contact (probe) and contactless (wave) methods of diagnostics are discussed, taking into account the nonuniform plasma distribution in the coaxial line and the specific features of its construction.

Eu3+ as a luminescent probe for local site symmetry in Eu(III) coordination compounds

The paper deals with the use of tripositive ion Eu3+ as a luminescent probe for the evaluation of the local site symmetry in coordination compounds with europium(III) content. The energy levels of the Eu3+ multiplets in the ligand matrix may be split by the crystal field into a maximum number of 2J+1 components, depending on the site symmetry of the Eu3+ ion. Analysis of photoluminescence spectra provides information on the local site symmetry of the compound. The topic is discussed with reference to literature data as well as own experimental results obtained in the Laboratory of Optoelectronics "A. Andries" of the Institute of Applied Physics. This work gives a deeper insight into the spectral characteristics of Eu3+ ions in ligand matrices and can be a guiding support for investigation of photoluminescence in Eu(III) complexes.

The Institute of Applied Physics – leader in the field for 60 years

It describes the 60-year history of the Institute of Applied Physics of the State University of Moldova and its main milestones: formation of the basic laboratories and production sectors, pilot production, and launching the journal „Elektronnaya obrabotka materialov” (Electronic Processing of Materials), consolidation of the scientific potential, training of highly qualified personnel, organization of conferences, effective cooperation, participation in national and international projects, scientific schools, development of activity ensuring a closed cycle - from basic research to applied research, to widely used technologies and technical means, main aspects of optimizing the structure, updating the research theme, development of innovative activities. It is stressed that the Institute of Applied Physics, with its traditions, experience and aspirations, has been and remains open to those who wish to pursue their doctoral and postdoctoral studies or to collaborate with its well-coordinated team.

A panel discussion on AI for science: the opportunities, challenges and reflections.

Artificial intelligence (AI) tools are changing the way we do science. AlphaFold basically solved the conundrum of protein structure prediction; DeepMD greatly improved the efficiency and accuracy of molecular simulations; and the emerging large language models such as ChatGPT are opening up more possibilities for scientific applications. In this panel, five experts from China and the US discussed the concept, development, bottlenecks and opportunities of AI for Science (AI4S), as well as their understanding of the relationship between AI and science. Roberto Car Professor at Department of Chemistry, Princeton University, USA Weinan E Professor at School of Mathematical Sciences, Peking University, China; AI for Science Institute, Beijing, China David Srolovitz Professor at Department of Mechanical Engineering, University of Hong Kong, China Han Wang Professor at the Institute of Applied Physics and Computational Mathematics, Chinese Academy of Sciences, China Linfeng Zhang (Chair) Chief scientific officer of DP Technology, China; AI for Science Institute, Beijing, China.

The Sixtieth Anniversary of the Institute of Applied Physics of Moldova State University. Traditions and Modernity

The Sixtieth Anniversary of the Institute of Applied Physics of Moldova State University. Traditions and Modernity

Conservativeness Study on the Seismic Analysis Method for Research Reactor Plant Structure Based on TMSR-LF1

The seismic performance analysis of research reactor plants is crucial for ensuring the safety of the entire reactor system. This paper analyzes the plant structure seismic performance of the 2WMt Thorium Molten Salt Reactor-Liquid Fuel 1 (TMSR-LF1) at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences under the action of frequent earthquakes, fortification earthquakes, and rare earthquakes was analyzed by finite element software PKPM based on the seismic design method of civil code +1°. On this basis, a comparison was made between the seismic responses of structural pushover analysis and elastoplastic time history analysis under the action of rare earthquakes, and the conservatism of these two commonly used methods for elastoplastic analysis was systematically analyzed. The results indicate that the TMSR-LF1 plant structure exhibits well bearing and deformation capacity. It meets the seismic design goal of “no damage under small earthquakes,” “no unrepairable damage under medium earthquakes,” and “no collapse under large earthquakes (using static pushover analysis),” and the critical regions are entirely within the elastic range. Furthermore, the analysis reveals that the elastoplastic time history analysis method produced a significantly higher seismic response than the pushover analysis method, which indicates the conservativeness of the time history method. Therefore, it is recommended to use the elastoplastic time history analysis method to evaluate the seismic performance of research reactor plants under rare earthquake actions. The research in this paper provides important references for the seismic performance analysis of other Class II research reactor plants.

Preliminary Performance Assessment of the Wave Parameter Retrieval Algorithm from the Average Reflected Pulse

To obtain new information about surface waves, it is proposed to use an underwater acoustic wave gauge, and an assessment of its effectiveness can be performed using a numerical simulation and field experiment. A new device, an underwater acoustic wave gauge named “Kalmar”, was developed by the Institute of Applied Physics of the Russian Academy of Sciences for long-term, all-weather monitoring of wind waves. The instrument uses ultrasound to probe the water surface from underwater and can be used to verify remote sensing data. In this work, the capabilities of the device are tested and compared with ADCP data. Two independent methods for processing underwater acoustic wave gauge data are discussed and compared. One of them is completely new for acoustic measurements and is based on the analysis of the shape of the reflected acoustic pulse averaged over space and time. The other allows processing individual reflected pulses and calculating the time implementation of the distance to the water surface. It is shown that two independent methods of significant wave height retrieval from the acoustic wave gauge measurements are highly correlated. The “Kalmar” acoustic wave gauge and the RDI WH-600 acoustic Doppler current profiler operated simultaneously at the test site in Gelendzhik from 1 February to 10 February 2020. The significant wave heights measured by the two instruments are in good agreement.

Microstructural evolution of silicon carbide fiber under argon ion irradiation at room temperature

In current work, irradiation-induced microstructural evolution of the Cansas 3303 SiC fiber was investigated. This fiber was irradiated by 1.8 MeV argon ions at room temperature in the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. The ion fluences were 5 × 1014, 1 × 1015, 2.5 × 1015 and 5 × 1015 ions/cm2 corresponding to the maximum doses of 0.27, 0.54, 1.35 and 2.70 displacements per atom (dpa), respectively. Irradiation effects were characterized by using micro-Raman spectroscopy and transmission electron microscopy. The results showed that the Cansas 3303 fiber consists of nanocrystalline SiC grains, carbon packets and carbon ribbons. Irradiation-induced amorphization accompanied with the decrease of SiC grain size was observed in the fiber with the increase of ion fluences. However, SiC grains still remained in this fiber up to the dose of 2.70 dpa. Besides, the reduction of the quantity and size in carbon packets and the annihilation of carbon ribbons in this fiber were also detected.

Application of Chemical Metallization of Photopolymer Structures Additive Technology in the Production of Components for Electronic Devices.

In this paper, we studied the operability of various components of vacuum electronic devices manufactured using the novel chemical metallization of photopolymer 3D-printed structures technology (CMPS), which is being applied at the Institute of Applied Physics, Russian Academy of Sciences (IAP RAS), for operation from microwave to sub-terahertz ranges. The key feature of this production method is the 3D printing (SLA/DLP, MJM technologies) of products and their further metallization. The paper presents the main stages of the process of chemical copper plating of polymer bases in various electrodynamic systems with complex shapes. A significant difference in the geometry and operating conditions of the created elements forms certain approaches to their production, as described in this work. Experimental studies of the implemented microwave components were carried out up to 700 GHz in the "cold" measurements; some electrodynamic structures were examined under conditions of sub-gigawatt peak power; and complex-shaped electrodes with cooling channels were tested under a continuous high thermal load. The conducted research has demonstrated the high potential of the developed methods of additive manufacturing of microwave device components and the prospects for their successful application in the described areas.

Overcoming the Matrix Effect in the Elemental Analysis of Steel: An Interview with 2023 Meggers Award Winner Johannes Pedarnig

The William F. Meggers Award was established in 1970 to honor its namesake, referred to by the National Institute of Standards and Technology on their website as “Dean of American Spectroscopists,” for his notable contributions to that field. This year’s recipient, Johannes Pedarnig of the Institute of Applied Physics at Johannes Kepler University (Linz, Austria) has recently investigated the optical emission of plasma on industrial steel samples utilizing laser ablation-spark discharge-optical emission spectroscopy (LA-SD-OES) and laser-induced breakdown spectroscopy (LIBS). Pedarnig spoke to Spectroscopy about this work as well as what winning the Meggers Award means to him.

Microwave radiometer observations of the ozone diurnal cycle and its short-term variability over Switzerland

Abstract. In Switzerland, two ground-based ozone microwave radiometers are operated in the vicinity of each other (ca. 40 km): the GROund-based Millimeter-wave Ozone Spectrometer (GROMOS) in Bern (Institute of Applied Physics) and the Stratospheric Ozone MOnitoring RAdiometer (SOMORA) in Payerne (MeteoSwiss). Recently, their calibration and retrieval algorithms have been fully harmonized, and updated time series are now available since 2009. Using these harmonized ozone time series, we investigate and cross-validate the strato–mesospheric ozone diurnal cycle derived from the two instruments and compare it with various model-based datasets: the dedicated GEOS-GMI Diurnal Ozone Climatology (GDOC) based on the Goddard Earth Observing System (GEOS-5) general circulation model, the Belgian Assimilation System for Chemical ObsErvations (BASCOE) – a chemical transport model driven by ERA5 dynamics, and a set of free-running simulations from the Whole Atmosphere Community Climate Model (WACCM). Overall, the two instruments show very similar ozone diurnal cycles at all seasons and pressure levels, and the models compare well with each other. There is a good agreement between the models and the measurements at most seasons and pressure levels, and the largest discrepancies can be explained by the limited vertical resolution of the microwave radiometers. However, as in a similar study over Mauna Loa, some discrepancies remain near the stratopause, at the transition region between ozone daytime accumulation and depletion. We report similar delays in the onset of the modelled ozone diurnal depletion in the lower mesosphere. Using the newly harmonized time series of GROMOS and SOMORA radiometers, we present the first observations of short-term (sub-monthly) ozone diurnal cycle variability at mid-latitudes. The short-term variability is observed in the upper stratosphere during wintertime, when the mean monthly cycle has a small amplitude and when the dynamics are more important. This is shown in the form of strong enhancements of the diurnal cycle, reaching up to 4–5 times the amplitude of the mean monthly cycle. We show that BASCOE is able to capture some of these events, and we present a case study of one such event following the minor sudden stratospheric warming of January 2015. Our analysis of this event supports the conclusions of a previous modelling study, attributing regional variability of the ozone diurnal cycle to regional anomalies in nitrogen oxide (NOx) concentrations. However, we also find periods with an enhanced diurnal cycle that do not show much change in NOx and where other processes might be dominant (e.g. atmospheric tides). Given its importance, we believe that the short-term variability of the ozone diurnal cycle should be further investigated over the globe, for instance using the BASCOE model.

Preface

The 2023 4th International Conference on Advanced Materials and Clean Energy (ICAMCE 2023), supported by Jiangsu University School of Materials Science & Engineering, is to publish the latest results of research and development on the material and energy science and technology. The seminar has been held since 2020, therefore in 2023 is its fourth session.ICAMCE 2023 took place in Hangzhou, China during 17th to 19th February 2023 (virtual form) with about 60 attendees. The main objective of the Conference is to provide an international cooperation and exchange platform for experts and scholars in the field to deliberate latest developments and future directions in Advanced Materials and Clean Energy, and an opportunity for enterprise developers to discuss existing problems and challenges, and explore frontier science and technology.We have invited several resources persons from different parts of China and other about 10 countries to deliver expertise lectures by imparting the latest findings from their respective research domains. Hui Pan is a professor from the Institute of Applied Physics and Materials Engineering and Department of Physics and Chemistry in the Faculty of Science and Technology at the University of Macau, China. In his research, a combined computational and experimental method is used to design and fabricate novel nanomaterials for applications in green energy and environments (such as electro-/photo-catalysis, water splitting, CO2/N2 reduction, and fuel cells), electronic/quantum devices, and spintronics. He has published more than 230 papers in international peer-reviewed journals, such as Phys. Rev. Lett., Adv. Energy Mater., and Chem. Mater.. It was a great opportunity for the students, researchers and engineers to interact with the experts and specialists to get their advice or suggestions.The proceedings of the present Conference covers the following topics: New Semiconductor Materials, Optoelectronic Materials, Composite Materials for Wind Power Generation, Welding and Connection, Alternative Energy Technologies, Clean Energy Systems and Technologies, Thermodynamics and Energy Optimization, etc.. Arigorous peer review process was conducted to check the quality, originality, innovation point of the papers accepted in this proceedings which will be published in the format of printed books.We would like to express our sincere thanks to all the authors for their research contributions, and also to the organizers of the Conference for their valuable spadework. Also, our heartfelt thanks and appreciation to the Editors and Managers, Journal of Physics: Conference Series of IOP Publishing Ltd. for their help and kind cooperation during the preparation of the proceedings.We hope you will benefit from all the manuscripts of the proceedings and learn new and novel ideas!The Committee of ICAMCE 2023List of Committee Member is available in this Pdf.

Photoinjector Complex at the Russian Academy of Sciences’ Institute of Applied Physics: Calculated Parameters and Current Stage of Development

Photoinjector Complex at the Russian Academy of Sciences’ Institute of Applied Physics: Calculated Parameters and Current Stage of Development

Photoinjector complex in IAP RAS: design parameters and current state of realization

The calculated parameters of the photoinjector electron accelerator currently being implemented at the Institute of Applied Physics are presented, and the current state of work is described. The complex provides a step-by-step increase of the average energy of particles in dense electron bunches up to 20 MeV, which opens possibilities for the implementation on its basis of a wide class of electromagnetic radiation sources.

Theoretical and experimental studies of W-band relativistic surface-wave oscillator of planar geometry

This paper presents the results of theoretical and experimental studies of a surface-wave oscillator (SWO) of planar geometry excited by a ribbon high-current relativistic electron beam. Within the framework of the quasi-optical approach and direct three-dimensional particle-in-cell modeling, we demonstrate the advantages of open transverse edged configuration against the closed one for effective mode selection at a fairly large oversize factor. In the experiments carried out on the basis of the SINUKI accelerator (Institute of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, 1 kA/650 keV/17 ns), we form a magnetically guided ribbon electron beam with a cross-section of 0.3 × 20 mm2, which moves parallel to a slow-wave structure with a period of 1.75 mm. A planar W-band SWO both of open and closed edged configuration has been experimentally tested. In full agreement with modeling, the open configuration exhibits much more stable operation, where at a frequency of 75 GHz, we observe pulse generation with duration of about 7 ns. The output power measured by the calorimetric method reaches 25 MW.

Протонна літографія: Світовий досвід та перспективи в Україні

Proton beam writing is a promising lithography method that is being developed in many countries. This method has significant advantages over other lithography methods, amongst all, there is the absence of the need for prefabricated pattern masks and a high aspect ratio of fabricated structures. Numerous publications demonstrate prospective applications of proton beam writing in different fields related to micro- and nanostructures fabrication. Proton beam writing may be used both for nanoelectronics and three-dimensional microstructures with a high aspect ratio. Work on proton beam writing technology is being conducted at the Institute of Applied Physics of the National Academy of Sciences of Ukraine. Last years there were introduced vector proton beam writing method, an electrostatic blanker system for proton beam distortion, and experiments on proton beam writing on chitosan films were conducted, including the films covered with thin films of metals and metal compounds.

Pavlinsky Geliy Veniaminovich (1935–2023)

Pavlinsky Geliy Veniaminovich (1935–2023)

Development of Three-Axis Fibre-Optic Seismograph for Direct and Autonomous Monitoring of Rotational Events with Perspective of Historical Review.

The paper presents historical perspective of fibre-optic seismographs designed and constructed at the Institute of Applied Physics at Military University of Technology, Poland based on the so-called minimum configuration of fibre-optic gyroscope. The briefly presented history, which originated in the 1998 by the system named GS-13P, laid solid foundations for the construction of a three-axis fibre-optic seismograph. The presented system meets all technical requirements of rotational seismology in terms of measurement parameters (measuring range from 10-8 rad/s to several rad/s and frequency from 0.01 Hz to 100 Hz) and utility features (mobility, autonomy, power independence, environmental stability). The presented device provides universal application both for research in engineering applications (high buildings, chimneys, wind towers) as well as in seismological research.

Numerical Investigation of Freeze Valve Melting Behavior in Molten Salt Reactor using OpenFOAM

Molten Salt Reactor (MSR) used a freeze valve to handle accident conditions when the reactor overheated and the active safety control systems failed. The freeze valve will melt if the reactor core temperature increases and exceeds the freeze valve’s melting temperature. In this research, a numerical investigation of freeze valve melting behavior was conducted. Freeze valve geometry used geometry proposed by Oak Ridge National Laboratory (ORNL) in Molten Salt Reactor Experiment (MSRE) and also used in test loop facility in Shanghai Institute of Applied Physics (SINAP) to develop Thorium Molten Salt Reactor (TMSR). The material used FLiNaK salt (LiF-NaF-KF, 46.5-11.5-42.0 mol %). Numerical calculation performs using OpenFOAM. BuoyantPimpleFoam was used to analyze the heat transfer mechanism. Isothermal phase-change simulated by adding solidificationMeltingSource terms into fvOptions as a flexible framework in OpenFOAM.