bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissociative electron attachment to supersonically cooled oxygen
Authors: Nandi D , Jana I , Ramaprasad V
Published: June 2020

Synopsis

Formation of O− and

O
2
−

ions via DEA to a supersonic jet of O2 having weakly bound van der Waals clusters is reported. The ion-yields show three peaks near 7, 11 and 16 eV electron energies where the 7 eV peak arises from the 2Π
u
state of

O
2
−

. The 11 and 16 eV peaks are ascribed to two resonance states

2

Σ

g
+

and

2

Σ

u
+

respectively, through a violation of σ−
selection rule. Ar was used as a refrigerant carrier gas and cross-section dependence of the two new peaks on the proportion of carrier gas used is experimentally observed, eventually leading to an optimum O2 : Ar ratio.
Electron impact scattering study on formyl fluoride (HFCO)
Authors: Jani T , Yadav H , Prajapati D , Vinodkumar M , Vinodkumar P C
Published: June 2020

Synopsis

Electron impact scattering studies with organic compounds play a significant role in studies related to astrophysics and radiation physics. We present here electron impact scattering studies on formyl fluoride as no cross-sectional data is available to the best of our knowledge. Total scattering cross sections (TCS) on comparing with iso-electronic molecule reveals that at low energy molecular dipole moment plays a significant role in cross-section deviation and at high energy the tendency seems to be same in all the formyl series.
Measurement and analysis of emission spectrum of laser-produced Ni plasma in the range of 7-14 nm
Authors: He S Q , Su M G , Cao S Q , Wu L , Lu H D , Min Q , Sun D X , Dong C Z
Published: June 2020

Synopsis

We measured and analyzed the emission spectrum of laser-produced Ni plasma in the range of 7-14 nm. The dominant transition arrays were identified as 3p63dn−3p63dn−1f and 3p53dn+1−3p53dn4f from Ni6+ to Ni9+ ions with aid of the Hartree-Fock calculations with configuration interaction effects. The plasma parameters have been obtained by comparison of experimental and simulated spectrum based on a steady-state collisional-radiative (CR) model.
Strong enhancement of electron-ion recombination induced by free-bound and bound-bound resonance transitions
Authors: Kislov K S , Narits A A , Lebedev V S
Published: June 2020

Synopsis

The role of free-bound and bound-bound resonant nonadiabatic transitions on electron-ion recombination in plasma of noble gas mixtures is studied. A kinetic model of recombination is proposed which includes the energy relaxation in collisions with electrons, resonant and non-resonant electron capture to Rydberg states through collisions of atomic ions with neutral particles, and resonant n → n’ transitions. It is shown that the resonant processes considered may strongly enhance total recombination coefficient even at relatively high degrees of ionization of plasma.
Investigation of temporal-resolved spectra of laser-produced titanium plasmas
Authors: Zhang D H , Zhao J N
Published: June 2020

Synopsis

Laser-produced titanium (Ti) plasmas have been measured using temporal-spatially resolved laser-produced plasma emission spectroscopy technique. The emission peaks in the wavelength range of 7.5-15 nm were identified from the 3s-(4,5)p, 3p-4d, and 3d-4f transition lines from Ti5+ to Ti11+ ions with aid of NIST database and Cowan atomic structure calculations, as well as comparative analysis between experimental and simulated spectra based on a simplified radiation hydrodynamic model.
Polarization of terahertz radiation driven by incommensurate two-color laser pulses
Authors: Li Y N , Wang G L , Zhang L , Jiao Z H , Zhao S F , Zhou X X
Published: June 2020

Synopsis

We investigate the polarization characteristics of terahertz (THz) emission from gaseous plasma induced by the two-color incommensurate femtosecond laser fields, which contains a circularly polarized laser field and a linear pulse. Our simulations show that strong linearly, elliptically, and circularly polarized THz radiation can be generated, by choosing appropriate wavelength, carrier-envelope phase and intensity for linear pump pulse.
Spectroscopic diagnostic of isolated dense plasma generated through laser driven gold hohlraum radiation
Authors: Ren J , Zhao Y , Deng Z , Qi W , Cheng R , Wang X , Liu W , Ma B , Yin S , Chen B , Feng J , Wang S , Fang Q , Cui B , Zhou X , Zhou W , Cao L
Published: June 2020

Synopsis

Through indirectly heating a TAC foam with ns laser driven gold hohlraum radiation, isolated, highly homogeneous and long-living dense ionized matter was generated in laboratory. This provide a fantastic sample for investigation of dense plasma science and technology. The emission spectra of the plasma with time, spatial and spectral resolution were measured with various techniques. The temperature and electron density are precisely diagnosed on the basis of the spectra.
Fast atom interaction with surfaces at grazing incidence: classical and quantum scattering applied to thin film growth
Authors: Staicu Casagrande E M , Momeni A , Khemliche H
Published: June 2020

Synopsis

Characterization of solid surfaces with heavy particles has mainly relied on the use of ions at energies from keV to MeV. Although atomic diffraction at thermal energies has been known since 1930 and became popular in the 1970’s as a powerful surface characterization technique, it is nowadays rather confidential. Unexpectedly, diffraction with atoms in the keV range has also been observed despite the tininess of the de Broglie wavelength. Grazing Incidence Fast Atom Diffraction (GIF AD) has now become mature and allows the real-time analysis, during the growth, of the most fragile layers.
Investigation of the potential sputtering process on the solid Ne surfaces induced by grazing incidence of slow Ar
q+
Authors: Sawa H , Ueta H , Hirayama T
Published: June 2020

Synopsis

For the quantitative investigation of the potential sputtering process on the surface of noble gas solid, we have performed the coincidence measurement of the ions desorbed and projectiles scattered from solid Ne surfaces, due to 3 keV Ar6+ impacts at grazing incidence angles. The dependence of

Ne

n
+

desorption on the charge state of the scattered Ar projectiles is found.
Theoretical models of stopping and ionization of metallic targets and oxydes bombarded by H2
+ molecules
Authors: Archubi C D , Arbó D , Arista N R
Published: June 2020

Synopsis

We study the vicinage effects in the interaction of H2
+ projectiles with C, Al, Si, Al2O3 and SiO2 targets considering the excitation of inner shells. On one side we extend the use of the semiclassical impact-parameter model for the excitation of atomic shells, considering quantum corrections and the role of target screening in the vicinage effects. On the other hand, we adapt our extended wave packet model (EWPM) [3] to the calculation of stopping ratios and ionization cross sections for correlated ions. Lindhard model is used to evaluate valence electrons contributions.
Non-statistical fragmentation of C60 and the formation of endohedral defect fullerenes
Authors: Stockett M H , Wolf M , Gatchell M , Schmidt H T , Zettergren H , Cederquist H
Published: June 2020

Synopsis

We report the first observation of the endohedral defect fullerene complex

He@C

59
−

and the first measurement of the threshold displacement energy of a fullerene.
IRMPD spectroscopy and QC calculations on functionalized gold nanocluster ions
Authors: Desfrançois C , Beydoun A , Lecomte F , Nieuwjaer N , Manil B , Scuderi D
Published: June 2020

Synopsis

Many studies are devoted to functionalized metallic nanoparticles, for many applications: in Physics, due to their localized surface plasmon resonances; in Chemistry, due to their specific catalytic properties that depend on their surface nature; in Biology, due to their optical or magnetic properties coupled to their potential for targeting and vectorization of bioactive molecules within living cells. In this last domain, gold and silver nanoparticles are especially of interest and, for the control of their biological effects, it is very important to have a fine knowledge of the structural properties and the chemical stabilities of their functional ligands.
Towards prediction of the rates of antihydrogen positive ion production in antihydrogen-excited positronium reaction
Authors: Yamashita T , Kino Y , Hiyama E , Piszczatowski K , Jonsell S , Froelich P
Published: June 2020

Synopsis

We present the 4-body calculation of the antihydrogen-positronium scattering aiming at the prediction of cross sections for the production of antihydrogen positive ions. The latter are expected to be a useful source of ultra-cold atoms for the test of matter-antimatter gravity. We convert the Schrödinger equation to a set of coupled integro-differential equations that involve intermediate states and are solved using the compact finite difference method. We will present the investigation of the rearrangement reaction between the ground-state antihydrogen atom and the excited positronium.
Configuration space method to calculate rearrangement matrix elements
Authors: Fursa D V , Utamuratov R , Kadyrov A S , Bray I
Published: June 2020

Synopsis

A new method based on partial-wave expansion of the Ps radial wave functions has been developed for calculating the Ps-formation matrix elements. The method utilises the Euler-Wijngaarden tansformation to accelerate slowly converging series. The integrals in the method are free of the Coulomb singularity that appears in previously used momentum-space methods and therefore more straightforward to apply to complex and charged targets. The results are compared with the existing benchmark calculations for positron scattering on H and He+ targets.
Electron and positron scattering from pyridine
Authors: Sinha N , Sahoo A K , Antony B
Published: June 2020

Synopsis

Advancement in medical technology is a much needed demand in the present scenario. To stem a robust technology, one should be aware of the knowledge behind such sciences. In view of this, we investigate here the interaction of biomolecules with the most elementary particle, electron along with its anti-particle positron. The cross sections computed here using SCOP formalism for pyridine molecule will be useful for simulations of bio molecular systems. We further compare the cross sections for e−and e+scattering extracting some rudimentary information about these basic interactions.
Performance of a scintillator-based ion detector for CRYRING@ESR
Authors: Menz E B , Hahn C , Pfäfflein P , Weber G , Stöhlker Th
Published: June 2020

Synopsis

A detector based on the scintillator material YAP:Ce and capable of counting single ions is present-ed. The detector consists of a YAP:Ce crystal and a light guide operating in ultra high vacuum and a convention-al photomultiplier outside the vauum. The crystal demonstrated the necessary radiation hardness against heavy ion irradiation. The detector has been commissioned at CRYRING@ESR and its detection capabilities have been confirmed with beam from the local source.
Spontaneous decay of small carbon cluster dianions

Cn2−

(n=7-11)
Authors: Najeeb P K , Stockett M H , Anderson E K , Eklund G , Kristiansson M K , Rosén S , Chartkunchand K C , Gnaser H , Golser R , Hanstorp D , Cederquist H , Schmidt H T , Zettergren H
Published: June 2020

Synopsis

We have studied the stabilities of small carbon dianion clusters,

C

n

2
−

(n = 7 – 11) in the cryogenic electrostatic ion storage ring, DESIREE. We observe spontaneous electron emission for tens of milliseconds, where dianions containing an even number of carbons decay slower in comparison to their neighbouring cluster sizes. For all the systems considered here, we find that there is a component which is stable at least on the time scales of hundreds of milliseconds.
Coupling of a velocity-map imaging spectrometer with an electron cyclotron resonance ion source
Authors: Concina B , Lépine F , Martin S , Bordas C
Published: June 2020

Synopsis

A velocity-map imaging spectrometer has been coupled with an electron cyclotron resonance ion source for the first time. This new set-up aims at the study of the photodetachment of benchmark molecular anions, especially thermionic emission. First measurements have been taken on SF6
−.
Electron transfer to phenyl boronic acid upon potassium collisions
Authors: da Silva F Ferreira , Pamplona B , Mendes M , García G , Limão-Vieira P
Published: June 2020

We present negative ion formation from collisions of neutral potassium atoms with neutral phenylboronic acid C6H5B(OH)2 molecules in the lab frame energy range from 10 to 1000 eV. From the assignment of the negative ion time-of-flight (ToF) mass spectra, BO− is the main fragment detected at energies below 100 eV, however above 100 eV BO2
− is the predominant fragment accounting on average for 30% of the total anion yield for collision energies above 250 eV. The rich fragmentation pattern results in the formation of more than thirty fragment anions, with twenty boron containing ions.
Resonances in molecules and molecular clusters
Authors: Gorfinkiel Jimena D
Published: June 2020

Resonances play an important role in a number of atomic and molecular processes. Identifying and characterising resonances in electron scattering is essential as they can both enhance a number of processes (e.g. electronic and vibrational excitation) and are crucial in others like dissociative electron attachment and dissociative recombination. We discuss recent theoretical studies of shape and core-excited resonances, both in isolated molecules of biological relevance and in small molecular clusters. The latter are investigated to understand the effect of the environment, in particular hydration, in electron collisions in biological matter.
Towards prediction of the rates of antihydrogen positive ion production in collision of antihydrogen with excited positronium
Authors: Yamashita T , Kino Y , Hiyama E , Piszczatowski K , Jonsell S , Froelich P
Published: June 2020

We present a 4-body calculation of scattering between an antihydrogen atom (

H
¯

) and a positronium (Ps) aiming at the prediction of cross sections for the production of antihydrogen positive ions

H
¯

+

. The antihydrogen positive ions are expected to be a useful source of ultra-cold anti-atoms for the test of matter-antimatter gravity. We convert the Schrödinger equation to a set of coupled integro-differential equations that involve intermediate states which facilitate the internal region description of the scattering wavefunction. They are solved using a compact finite difference method. Our framework is extended to scattering between an excited Ps and H. Cross sections of the reactions, Ps (1s/2s/3s)

H
¯

→

e
−

+

H
¯

+

, in s-wave collisions, are calculated. It is found that the reactions originating from Ps (1s/2s) +

H
¯

produce

H
¯

+

with a constant cross section within 0.05 eV above the threshold while the reaction cross section from Ps (3s) decreases as the collision energy increases in the same energy interval. Just above the threshold, the cross section of

H
¯

+

production from Ps (3s) +

H
¯

in s-wave collision is 7.8 times larger than that from Ps (1s) +

H
¯

in s-wave and 2.3 times larger than that from Ps (2s) +

H
¯

in s-wave. The near-threshold de-excitation reaction from Ps (3s) +

H
¯

occurs more rapidly than the

H
¯

+

production.
Cold collisions of

C2−

with Li and Rb atoms in hybrid traps
Authors: Kas Milaim , Liévin Jacques , Vaeck Nathalie , Loreau Jérôme
Published: June 2020

We present a theoretical investigation of reactive and non-reactive collisions of Li and Rb atoms with

C
2
−

molecular anions at low temperatures in the context of sympathetic cooling in hybrid trap experiments. Based on accurate potential energy surfaces for the singlet and triplet states of the Li–

C
2
−

and Rb–

C
2
−

systems, we show that the associative electronic detachment reaction is inefficient but that it occurs with a large rate for collisions involving excited states of either Li/Rb or

C
2
−

. We also investigate rotationally inelastic collisions in order to explore the cooling of the translational and rotational degrees of freedom of

C
2
−

in hybrid ion-atom traps. The effect of micromotion is taken into account by considering Tsallis distributions of collision energies. We show that the translational cooling occurs much more rapidly than rotational cooling and that the presence of excited atoms leads to losses of anions on a timescale comparable to that of rotational cooling.
Temporal-spatial double slit interference of photoelectron
Authors: Liang H , Xiao X R , Peng L Y
Published: June 2020

Synopsis

The electron displacement induced by an ultrashort pulse is theoretically investigated. We propose and numerically demonstrate a scheme to accurately measure the electron displacement using a ruler formed by the interfering spirals in the photoelectron momentum distribution generated by two oppositely circularly polarized pulses. It can be understood as a temporal double-slit with an additional spatial shift on one slit.
The single ionization of helium with energy-selected extreme ultraviolet photons
Authors: Zhang M , Hai B , Zhao D M , Dong D P , Lei J T , Morishita T , Zhao S F , Zhang S F , Ma X
Published: June 2020

Synopsis

The platform dedicated to studies of extreme ultraviolet (EUV) laser on atom/molecule has been established recently at the Institute of Modern Physics, CAS, Lanzhou. The single ionization of helium with EUV photons of about 37.5 eV was conducted. Photoelectron angular distributions are obtained and compared with theoretical calculations from TDSE method.
Surface-near-field reconstruction from streaked photoelectron spectra of Au(111) surfaces
Authors: Ambrosio M J , Thumm U
Published: June 2020

Synopsis

We calculate attosecond streaking traces from Au(111) surfaces and suggest their use for characterizing the plasmonic/dielectric response of solids at the nanoscale.
Amplification of a train of attosecond pulses in a plasma-based X-ray laser driven by an IR field
Authors: Antonov V A , Han K C , Khairulin I R , Kocharovskaya O
Published: June 2020

Synopsis

We suggest a technique to amplify a train of attosecond pulses, produced via high-harmonic generation of an infrared laser field, in active medium of a plasma-based X-ray laser driven by a replica of the same IR field as used to produce high harmonics forming a train of attosecond pulses.
Angle-resolved time delays in photoionization with a high repetition rate laser source
Authors: Srinivas H , Shobeiryt F , Bharti D , Harth A , Pfeifer T , Moshammer R
Published: June 2020

Synopsis

Complete measurements of photoionization include both time-resolved and angle-resolved mapping of the atomic and molecular dynamics. The setup described in this work is suited to be used for attosecond pump-probe experiments as well as providing insights into the angular dependencies of photoionization.
A 17-W, mid-IR parametric amplifier driven by a Yb:YAG thin-disk laser and its application to high harmonic generation in solids
Authors: Kanai T , Lee Y , Seo M , Kim D E
Published: June 2020

Synopsis

We developed a carrier-envelope phase-stable, KTA parametric amplifier delivering 17-W mid-IR pulses (signal: 1.4 micron, idler: 3.8 micron) at a 100-kHz rep. rate. The key aspect is stable generation of supercontinuum seed pulses with 1.4-ps pulses, which are the longest for supercontinuum generation on its longer wavelength side. This technology offers a robust architecture with characteristics of stable phases, simple dispersion management, wavelength tunability for 1.3-4.5 micron, and this high photon flux opens novel statistics-driven spectroscopy for rare events in strong field physics.
Photoionization of neutral magnesium and sodium anion in C60 versus C240
Authors: Magrakvelidze M , Shields D , De R , Manson S T , Chakraborty H S
Published: June 2020

Synopsis

We investigate the effects of confinement and electron correlation on the photoemission properties of Mg and Na− endohedrally sequestered in C60 versus C240. Cross sections and Wigner-Smith time delays for emissions from various electronic levels are computed and analyzed in time-dependent local density approximation.
Delayed relaxation of highly excited naphthalene cations
Authors: Reitsma G , Hummert J , Dura J , Loriot V , Vrakking M J J , Lépine F , Kornilov O
Published: June 2020

Synopsis

The efficiency of energy transfer in ultrafast electronic relaxation of molecules depends strongly on the complex interplay between electronic and nuclear motion. In this study we use wavelength-selected XUV pulses to induce relaxation dynamics of highly excited cationic states of naphthalene. Surprisingly, the observed relaxation lifetimes increase with the cationic excitation energy. We propose that this is a manifestation of a quantum mechanical population trapping that leads to delayed relaxation of molecules in the regions with a high density of excited states.
Efficient table-top beamline for attosecond molecular and solid-state dynamics at the carbon K-edge
Authors: Barreau L , Ross A D , Kraus P M , Garg S , Neumark D M , Leone S R
Published: June 2020

Synopsis

A harmonic continuum extending up to 375 eV is generated from 750 μJ, 9 fs mid-IR pulses centered at 1300 nm. The development of this source and its use for attosecond transient absorption spectroscopy experiments at the carbon K-edge are discussed.
Low-order harmonic generation of helium atom in an intense laser fields
Authors: Zhou J-W , Jiao Z-H , Li P-C , Zhou X-X
Published: June 2020

Synopsis

We calculate the low-order harmonic generation (LOHG) by solving three-dimensional time-dependent Schrödinger equation with an accurate model potential of helium (He) atom in an intense laser fields. The satellite-peak structures of the LOHG are obtained in the harmonic spectra of He atom. We analyze the emission properties of the LOHG by employing a synchrosqueezing transform technique. Our results show that the satellite-peak structures contain the information of the bound states and the Stark shift of He atom in an intense laser fields.
Coupling of autoionizing states by a chirped laser pulse
Authors: Žitnik M , Mihelič A , Bučar K , Hrast M , Barba Ž , Krušič Š , Ribič P Rebernik , Urbančič J , Ressel B , Stupar M , Poletto L , Coreno M , Gauthier D , Ninno G De
Published: June 2020

Synopsis

We have observed the autoionization of the laser-coupled 2s2p
1
Po
and 2p
2
1
Se
resonances in helium. The ions were collected while varying the frequency and delay of the extreme-ultraviolet (EUV) excitation pulse with respect to the linearly chirped visible (VIS) laser pulse. From the measured frequency-delay map the Autler-Townes splitting, the EUV-VIS cross-correlation and the linear chirp parameter were extracted.
High-energy ultrafast mid-IR optical parametric amplifier for strong-field science
Authors: Faccialà D , Musheghyan M , Geetha P Prasannan , Pusala A , Crippa G , Ciriolo A G , Devetta M , Vozzi C , Stagira S
Published: June 2020

Synopsis

We present a high-energy mid-infrared optical parametric amplifier source tunable between 2.8 and 3.8 μm for strong-field applications. We exploited this source in combination with a 800 nm source for generating high-order harmonics in atoms and molecules in a two-color pulse scheme.
Floquet formalism for multiphoton dynamics in superconducting quantum circuits
Authors: Jooya H Z , Sadeghpour H R
Published: June 2020

Synopsis

High-order nonlinear multiphoton dynamics of closed and open periodically driven quantum systems are studied within the semiclassical Floquet formalism. Multiphoton up/down frequency conversion in a super-conducting circuit is realized and faithfully reproduced with calculations. The absorption spectra are suppressed at sharp avoided crossings of the Floquet states. We include the effect of coupling to cavity by time evolving the master equation. The characteristics of the time-averaged absorption spectra are investigated by probing details near and around the exceptional points where suppression occurs.
Frustrated tunnel ionization of argon by intense few-cycle infrared laser radiation
Authors: Pauly T , Smith N , Douguet N , Bartschat K
Published: June 2020

Synopsis

We report results for strong-field ionization and excitation of argon obtained by solving the time-dependent; Schrödinger equation in a single-active-electron model. We analyze the process of “frustrated tunnel ionization” and its dependence on the potential and a variety of laser parameters, such as the intensity, carrier-envelope phase, and ellipticity. Our calculations support current experimental work at Griffith University.
Branching ratio coherent control in ultrafast bond making
Authors: Amitay Z , Liat L , Reich D M , Kosloff R , Koch C P
Published: June 2020

Synopsis

Coherent control of bond making (photoassociation) is crucial for the realization of a new photochemistry, where a laser field is actively photo-driving the irradiated system in a coherent way from the initial state of reactants to the final state of desired products. In a significant step forward, we experimentally demonstrate here coherent control over the photoassociation branching ratio to different target states of the generated molecule. The model process is strong-field multiphoton femtosecond photoassociation of thermally hot magnesium atoms into bound magnesium dimer molecules.
Dependence of the returning electron wave packet on the model potential for high-energy plateau photoelectron spectra
Authors: Chen J H , Fan J , Li X Y
Published: June 2020

Synopsis

In the present work, we study the two-dimensional momentum distributions of high-energy plateau photoelectrons of a model-atom in a linearly polarized few-cycle laser pulse. Based on the improved strong-field approximation (ISFA), it is found that the returning electron wave packet is dependent of the model potential.
Super-interference in atomic photoionization: Moiré patterns in momentum maps
Authors: Dran M , Arbó D G
Published: June 2020

Synopsis

We theoretically investigate on the origin of lateral ring structures in the doubly differential momen-tum distribution for atomic ionization by laser pulses in the midinfrared spectral region. We demonstrate that such structures stems from the interplay between intra- and intercycle interference patterns which work as two separate grids in the two-dimensional momentum domain. When the periods of the two grids (intra- and intercycle) are similar, moiré patterns arise as concentric rings at high electron kinetic energy.
Photoelecton emission from silver nanoparticles after laser irradiation
Authors: Budai L , Márton Z , Dombi P , Tökési K
Published: June 2020

Synopsis

We present theoretical study of photoelectron emission from silver nanoparticles after laser irradiation based on the classical simulation of the electron trajectories. The individual electron trajectories were analized with and without taken into account the image force between the emitted electron and its mirror charge. We show also the calculated energy spectra in comparision with the available experimental data. We observed a significant effect of the image acceleration to the calculated electron spectra.
Radionuclide sorption onto nanoiron oxide: Synthesis and application to natural waters
Authors: Vasundhara Dasari , Grandhi Sarika , kumar Susarla Siva , Kaleswararao Thaticharla , Suryakala Duvvuri
Published: June 2020

Expanded requirement for the lanthanides in industrial stuff resulted in intensified manufacture of lanthanide containing ores. This increases public contact to the lanthanides, both from production wastes/effluents and from various commercial products. Present study describes the efficacy of γ-Fe2O3 (nano maghemite) for fast adsorption of some of the long-lived, toxic and radioactive human made radio nuclides from natural waters. Nanometal oxides have been successfully prepared by precipitation synthesis followed by thermal decomposition of transition metal oxides, These are further characterized by different physico-chemical techniques like XRD, UV-Vis-DRS, TEM, FTIR and BET analysis. Adsorption capacities of REEs like La(III), and Nd(III) are observed through ICPAES technique. The parameters influencing the adsorption capacity, which includes pH, contact time, initial concentration, and temperature are optimized. The adsorption kinetics and thermodynamics are analysed. These results proved that nanometal oxide (γ-Fe2O3) have been successfully prepared by precipitation synthesis followed by thermal decomposition of transition metal oxides, and followed a novel method to mollify the seriousness of nuclear waste contamination, which leads to successful evaluation for environmental problems.
Microstructural Investigation on Heat Treatment of Hypoeutectic High Chromium White Cast Irons
Authors: Ngqase Mbulelo , Pan Xiaowei
Published: June 2020

High chromium white cast irons (HCWCI) are widely used as abrasion resistant materials in cement manufacturing, mineral processing and slurry pumping industries. Their high resistance to wear in these demanding situations stems from the presence of hard eutectic (Cr, Fe)7C3 carbides in their microstructures. In this context, the properties of hypoeutectic iron of HCWCI containing 25 wt. %Cr-2.5 wt. %C were investigated after destabilisation heat treatments, cooling (slow and fast cooling) to ambient temperatures, their influence on the microstructure was investigated. For characterization of the hypoeutectic iron of HCWCI, several experimental tests were performed using the following laboratory equipment: light optical microscope, scanning electron microscope. The amount of retained austenite also depends on the alloying additions in the melt during melting processes, destabilisation temperatures, soaking time and the cooling rates during heat treatment processes.
Effect of V2O5 on the Properties of Lithium Bismuth Borate Glasses
Authors: Raut V D , Deshpande A V , Satpute N S
Published: June 2020

The series of the glasses with general formula (40-x)Li2O:30B2O3:30Bi2O3:xV2O5, with x = 0, 0.5, 1.0, 1.5 and 2.0 mol% was prepared using conventional quenching technique. The glass transition temperature Tg for these samples were determined from Differential Thermal Analysis. The glass transition temperature increases beyond 0.5 mol%. It was found that the glasses under study consist of randomly connected BO3 & BO4 structural units. The density and molar volume of glasses were found to depend on V2O5 content. Initially the density increases, molar volume and glass transition temperature decrease with the addition of V2O5. This suggests that when V2O5 is added to the glass initially up to 0.5 mol% it may be entering as a modifier. Beyond 0.5 mol% density decreases and molar volume increases as V2O5 goes as former. This reveals the role of V2O5 as a glass network former beyond 0.5 mol%. Optical band gap energy decreases and cut off wavelength increases with increase in V2O5 content.
Comparative Analysis of Sodium Hexa-titanate (Na2Ti6O13) & Sodium-Potassium Hexa-titanate (Na1.5K0.5Ti6O13)
Authors: Alam N , Khatoon T , Chandel V S , Azam A , Rashmi
Published: June 2020

The present paper discusses the synthesis and characterization of Sodium Hexatitanate (NHT) and Sodium-Potassium Hexa-titanate (NKHT) by solid state reaction method. The phase of the synthesized material was confirmed by XRD and the particle size has been calculated using Debye-Scherrer relation. Morphology of the surface and dimensions of the crystals have been analysed using FE-SEM analysis at different magnification. EDS analysis has also been done for elemental analysis of Sodium Hexa-titanate and Sodium Potassium Hexa-titanate. IR spectra has been recorded for getting various vibration modes of the samples.
Enhanced Electrical and Optical properties of Al doped and ZnO nanoparticles for Optoelectronic Application: Eco-friendly Green Route
Authors: Ragupathi Veena , Madhu babu Manukonda , Panigrahi Puspamitra , Ganapathi Subramaniam N.
Published: June 2020

Optoelectronic materials have been developed greatly due to the wide usage of Liquid crystal displays, touch screens and light-emitting devices. In this work, a simple, eco-friendly green synthesis method has been adopted for the synthesis of pure and Al doped ZnO nanoparticles (1, 3 and 5 wt. %). Bio-extract was extracted from Citrus Aurantium peel. The structural, optical and electrical properties of the as-synthesized material were analyzed by X-ray diffraction, Scanning Electron Microscopy, UV-Visible spectroscopy and Hall Effect measurements. XRD spectra indicate the presence of hexagonal wurtzite structure. The crystalline size is decreased with increasing Al concentration. Scanning electron microscopy results indicate that the addition of Al changes the morphology from rod shape to platelets shape. UV-Visible results infer the shift in the band edge towards lower wavelength and the bandgap increases with Al concentration. Hall effect measurements reveals the enhanced carrier concentration in 5 wt% Al doped ZnO with the values of 1.3 × 1021 cm−3.
Development and performance tests of μ-PIC with DLC electrodes
Authors: Ochi A , Yamane F , Ishitobi Y , Setsuda H
Published: June 2020

Micro pixel chambers (μ-PIC) with resistive cathodes have been developed as particle tracking/imaging detectors in high-rate high ionizing particle (HIP) environments. A main target of their development is as a forward muon detector in the ATLAS phase-2 upgrade. The cathode is made from DLC (diamond-like carbon) thin foil by the liftoff method. Using the resistive cathodes, the discharge (spark) probability within the HIP environment was reduced (10-1000 times) and two-dimensional readouts for the incident particles are available using a 400-micron pitch separated pixel array. We measured the tracking performances for the charged particles using a 140 GeV muon beam in CERN’s H4 beam line and also measured the imaging properties of 8 keV X-rays. Two-dimensional fine position resolutions (< 100 micron) were obtained. These results show that the resistive μ-PIC is one of strong candidate for forthcoming high-rate particle experiments.
New results from GridPix Detectors
Authors: Bilevych Y , Desch K , Fransen J-P , Van Der Graaf H , Gruber M , Hartjes F , Van Der Heijden B , Heijhoff K , Ietswaard C , John D , Kaminski J , Kluit P , Van Der Kolk N , Korporaal A , Ligtenberg C , Van Petten O , Raven G , Rövekamp J , Schiffer T , Schmidt S , Timmermans J
Published: June 2020

GridPix structures combine the high resolution of a pixel readout chip with a Micromegas as gas amplification stage. This detector has shown excellent performance before with the Timepix ASIC, but has been improved by using the successor ASIC, the Timepix3. This new version of the GridPix detectors has been used in test beams at the ELSA accelerator at Bonn, where 2.5 GeV electrons are available for tracking studies. It could be demonstrated that the spatial resolution in both transverse and longitudinal direction follows the diffusion function.

Structures made of four GridPixes have been designed and constructed to cover larger areas. Also these devices called quads have been successfully tested with the electron beam giving similarly good results as the single GridPix detector.
Effects of gas mixture quality on GEM detectors operation
Authors: Guida R , Mandelli B , Corbetta M
Published: June 2020

Gas Electron Multiplier (GEM) detectors have been successfully operated in the LHCb experiment and they will be installed in the CMS and ALICE experiments during LHC Long Shutdown 2. As for others LHC gaseous detector systems, gas mixture is individually provided by dedicated Gas Systems. Several studies have been performed in laboratory to characterize GEM performance from the point of view of their use in LHC Gas Systems, where many variables can influence detectors operation. A Triple-GEM prototype was tested with the aim of probing the possible effects of specific changes that could occur in the Gas System, such as variations in gas mixture composition, input gas flow and presence of impurities. A complete overview of the obtained results will be presented. The test confirms the importance of having a stable gas mixture composition, as it influences GEMs working point, with significant variations in the amplification gain. It was also seen how the input gas flow can affect GEMs performance, since it conditions the accumulation of humidity and air. Moreover, it was found that the presence of pollutants such as O2, N2 and H2O, commonly present during operation in the experiments, influences GEMs performance in terms of signal efficiency and amplification gain. While detector gain is weakly affected by the presence of N2, the presence of even small concentrations of O2 causes a significant performance decrease in terms of amplification gain.
Application of micro-pattern gas detectors in the present and future experiments in Budker INP
Authors: Fedotovich G. , Kozyrev A. , Kudryavtsev V. , Logashenko I. , Maltsev T. , Ruban A. , Shekhtman L. , Sokolov A.
Published: June 2020

Micro-pattern gas technology is planned for the upgrade of the tracking system of the CMD-3 detector at the VEPP-2000 electron-positron collider in Budker INP. The upgrade includes a new cylinder tracking and trigger detector that consists of two tracking layers at a radius of 32 to 33 cm with coordinate resolution close to 0.1 mm in Z (along the beam axis) and trigger segments of about 1 cm in phi. Another new coordinate subsystem includes two end-cap discs with active area between radius of 50 mm and 250 mm, that provides spatial resolution in R and in phi close to 1 mm as well as trigger signal from the phi segments. For these two subsystems we plan to use micro-RWELL technology because it allows much simpler assembling of large cylindrical detector and large discs due to more rigid glass-fiber support as compared to the triple GEM technology. The new cylindrical detector and end-cap discs of the CMD-3 are considered as a prototypes of the Inner Tracker of the detector for the future Super C-Tau Factory (SCTF) at Budker INP. The SCTF is an electron-positron collider for the energy range of 3-7 GeV in the center of mass system that will provide luminosity of 1035 cm−2s−1. Coordinate system of the detector for the SCTF will include among other systems, the Inner Tracker and the end-cap discs. The Inner Tracker will be 60 cm long and occupy radius up to 20 cm, while the end-cap discs will have radius up to 180 cm and will have to provide trigger signal. For the end-cap discs the MPGD option is considered based either on the triple-GEM or on the micro-RWELL, while for the Inner Tracker three main options are competing: compact Time Projection Chamber, silicon micro-strip tracker and cylindrical MPGD tracker. The first results of simulations with all these options are presented with preliminary discussion about the choice of the option.
MUon Survey Tomography based on Micromegas detectors for Unreachable Sites Technology (MUST2): overview and outlook.
Authors: Roche Ignacio Lázaro , Decitre J B , Gaffet S
Published: June 2020

The use of Micro-Pattern Gaseous Detectors in geophysics and civil engineering applications has experienced an increase related to the incorporation of muon tomography in these fields. The Temporal Tomography of Density by the Measurement of Muons project has developed a new direction-sensitive tool for muon flux measurement based on a thin time projection chamber with a bulk-Micromegas readout and SRS electronics. This configuration presents interesting distinctive features, allowing a wide angular acceptance of the detector with a low weight and compact volume. The functioning principle of the device, the results of the characterisation tests, the ongoing work to improve its performance and the next phase to scale up the existing muon camera network at the Low Background Noise Laboratory of Rustrel are presented.
Development of a low power and high integration readout ASIC for time projection chambers in 65 nm CMOS
Authors: Liu Wei , Deng Zhi , Li Fule , Gu Xian , Li Yulan , Qi Huirong
Published: June 2020

The paper presents the development of a low power readout ASIC for time projection chambers (TPCs) for the CEPC (Circular Electron Positron Collider) experiments. In order to achieve high spatial and momentum resolution, large number of readout channels is demanded with waveform sampling capability in the resolution of 8-10 bit and the sampling rate of 10-40 MS/s. Power consumption became critical and has been addressed by using advanced 65 nm CMOS process and simplifying the analog circuits in our design. The prototype chip has been developed including the analog front-end and the waveform sampling SAR (Successive Approximation Register) ADC. This paper will present the detailed circuit design and test results. The development of the digital trapezoidal filter will also be described.
Patch antenna for nonlinear radar
Authors: Balzovsky E V , Brezgulevsky D S
Published: June 2020

The design of a dual-band patch antenna for a nonlinear radar operating at combinational frequencies has been developed. The antenna has a rectangular emitter surrounded by dielectric layers over a metal screen. The emitter has a U-shaped slot. The results of simulation and measurements of the antenna sample parameters are presented. The antenna is matched with the feeder at the frequencies near 1.3 and 1.6 GHz, and in the range beyond these frequencies the antenna operates as a notch-filter. The antenna has a unidirectional pattern. The radiation maximum is directed perpendicular to the plane of the antenna.
On chiral medium with zero permittivity and permeability values
Authors: Fisanov V V
Published: June 2020

The possibility of propagation of electromagnetic waves of circular polarization in a Tellegen isotropic chiral medium with zero values of dielectric permittivity and magnetic permeability (chiral nihility) is considered. The refractive indices of normal waves are analyzed using the forward and backward wave identifier. In the presence of dissipative losses, the existence of two different normal waves in such a medium is impossible.
Implementation of techniques and design of equipment for the production of the food liquids
Authors: Drozdova T , Biryukov A , Kachaeva N , Nazarenko M , Stribizheva L , Strukova V
Published: June 2020

This article discusses the rationale for the implementation of techniques and design of equipment, allowing to assess the quality and authenticity of sparkling wines produced in the Krasnodar region. There is an urgent question about the methods of monitoring and detecting fraud in the production and import of sparkling wines at stable positive tendency to increase volumes of these products. The main drawback of the regulatory documentation is the lack of methods for recognizing the naturalness of products presented to the consumer, which increases the risks of producing products that do not meet the requirements. In this regard, the capabilities of software and hardware systems are shown, which make it possible to assess the quality and authenticity of sparkling and carbonated wines, as well as to study the physicochemical properties of food liquids with a two-phase “liquid-CO2” system. It was established that this set of techniques allows to determine the quality indicators of sparkling and carbonated wines, as well as to analyze the applied technological methods of production and to identify the authenticity of the analyzed object. An analysis of the sparkling properties of wine confirms the influence of the biochemical factor of yeast biomass on the processes of CO2 binding to wine components during champagne and shows a fundamental difference in the cavitation desorption of carbon dioxide from sparkling and carbonated wines.
ABS and PLA sub-terahertz absorbers for 3D-printing technology
Authors: Dorozhkin K V , Teterina D D , Badin A V , Moskalenko V D
Published: June 2020

The results of research of the dielectric properties of absorbers based on commercial composite plastics for 3D printing in the sub-terahertz frequency range are presented. Spectra of the complex dielectric constant of plastics based on acrylonitrile butadiene styrene and polylactide with the addition of carbon nanoparticles in the frequency range 115-258 GHz are shown. The calculated transmission, reflection, and absorption spectra for the layers of the adsorbent with a thickness of 0.5 to 2 mm are presented.
Dielectric permeability of multiwall carbon nanotubes based composites, which are measured by a resonator method
Authors: Chervinskaya A S , Dotsenko O A , Potselueva A A
Published: June 2020

The paper presents the results of measurements of the dielectric constant of composite materials, both solid and porous, containing multi-walled carbon nanotubes (MWCNT) as an inclusion, and water-dispersion color as a binder. The rectangular cavity was used to measurements. It is shown that the location of the sample in the cavity affects the accuracy of measurements. The permittivity spectra of the solid samples shows that the addition of nanotubes to the binder leads to shifting the dispersion range to the low-frequency region. The results show that materials can be used as radar absorbers.
Temperature distribution in microwave chamber using the phantom limb
Authors: Badin A V , Dunaevskii G E , Nechaev A N
Published: June 2020

This paper presents results of temperature distribution in the phantom limb under the influence of microwave radiation. Authors had been developed automated installation based on linear positioner and temperature detector for measuring thermal field distribution in phantom of human hand. It was shown that under the influence of impulse microwave radiation having a power of 40W at the phantom during 6 minutes leads to equable warming along longitudinal axis of phantom.
Background method of radar detection of a moving small target object in the task of classifying active radars
Authors: Anikin A S , Khristenko A V , Ochirtarov A V
Published: June 2020

The article deals with the classification of radar equipment based on two features: on the location of the receiving and transmitting points in space, as well as by the method of generating an informative signal at the receiving point. The most significant parameters in the development of a moving target detector near the underlying surface have been observed.
Lipid and protein dynamics that shape nuclear envelope identity
Authors: Bahmanyar Shirin , Schlieker Christian
Published: June 2020

The nuclear envelope (NE) is continuous with the endoplasmic reticulum (ER), yet the NE carries out many functions distinct from those of bulk ER. This functional specialization depends on a unique protein composition that defines NE identity and must be both established and actively maintained. The NE undergoes extensive remodeling in interphase and mitosis, so mechanisms that seal NE holes and protect its unique composition are critical for maintaining its functions. New evidence shows that closure of NE holes relies on regulated de novo lipid synthesis, providing a link between lipid metabolism and generating and maintaining NE identity. Here, we review regulation of the lipid bilayers of the NE and suggest ways to generate lipid asymmetry across the NE despite its direct continuity with the ER. We also discuss the elusive mechanism of membrane fusion during nuclear pore complex (NPC) biogenesis. We propose a model in which NPC biogenesis is carefully controlled to ensure that a permeability barrier has been established before membrane fusion, thereby avoiding a major threat to compartmentalization.
The ABCF gene family facilitates disaggregation during animal development
Authors: Skuodas Sydney , Clemons Amy , Hayes Michael , Goll Ashley , Zora Betul , Weeks Daniel L. , Phillips Bryan T. , Fassler Jan S.
Published: June 2020

Skuodas and Clemons et al. show that protein aggregation is pervasive during early development and that the ABCF family of soluble ATP-binding proteins, which are encoded by animal genomes and expressed embryonically, regulate disaggregation and are instrumental for a normal developmental program.