bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vibrational description of the LiAr molecule in its X
2Σ+ and A
2Π electronic states in the framework of an algebraic model
Authors: Sboui Insaf , Slama Marwa , Ghazouani Sami , Mounir Ben El Hadj Rhouma 
Published: April 2022

Abstract
In this work, the vibrational energy levels, the kinetic energy and the potential energy of the LiAr molecule in its X
2Σ+ and A
2Π electronic states are studied using the Morse potential and so(2, 1) spectrum generating algebra approach. An algorithm for the recursive evaluation of the expectation value of

Z

q

=

e

−
α
(
r
−

r

e

)

q

for a given state of Li (X
2Σ+) Ar and Li (A
2Π) Ar are proposed. As an application closed-form estimations for the value

r

n

of Li (X
2Σ+) Ar and Li (A
2Π) Ar were derived using Jensen’s inequality. This allows us to obtain several inequalities relating the radial expectation value

r

n

of Li (X
2Σ+) Ar and Li (A
2Π) Ar at the logarithme of the expectation value of

Z

q

=

e

−
α
(
r
−

r

e

)

q

. These obtained outcomes are compared to the published results, both theoretical and experimental, and show a good agreement.
Analysis of reproducibility by using inclusive and exclusive statistics in the framework of a bilateral comparison
Authors: Álvarez Liliana , Colin Castellanos Carlos , Giarmana Gastón , López Celis Armando , Beer Ethel 
Published: April 2022

Abstract
A comparison of 11 steel gauge blocks (8 short and 3 long) calibrated by absolute interferometry is presented. Thus, the results of the individual measurements of five designated signatories (three from INTI and two from CENAM) were analyzed in order to evaluate the impact of possible correlations and systematic effects in the reproducibility of the measurements. All measurements were carried out in the framework of a bilateral key comparison between CENAM and INTI and following their own calibration procedures. The measurement analysis was performed by using inclusive and exclusive statistics. The agreement between all measurements is satisfactory and no detectable systematic effects were observed. Average offsets were also calculated for each operator, verifying that systematic effects did not affect the measurements of the present exercise. Even though the approaches deployed to analyze the results are well-established, this work provides a detailed example of analysis in the field of gauge block metrology. This exercise has also allowed to validate the internal criteria considered by each institute for selecting final results.
Mechanical properties of metal–matrix composites reinforced with carbide structures
Authors: Morozov N F , Semenov B N , Smirnov V M , Zemtsova E G 
Published: April 2022

Abstract
Metal–matrix composites based on an aluminum matrix reinforced with ceramic particles are widely used as structural materials in the aerospace and automotive industries. The main problems in the manufacture are the uniformity of the distribution of particles over the volume, poor adhesion of ceramic particles to the matrix metal, and the formation of aluminum carbide at the interfaces, leading to undesirable embrittlement. We propose a new technique for the manufacture of metal–matrix composites, which consists in creating a composite material, when carbide nanostructures form a framework in the volume of an aluminum matrix, and which allows solving the above problems. A finite element model of deformation of a metal–matrix composite reinforced with carbide structures is constructed.
Reinforcement of polymer composite materials by titanium dioxide nanoparticles synthesized in plasma discharge under ultrasonic cavitation
Authors: Kolesnik S A , Bulychev N A 
Published: April 2022

Abstract
In this work, the synthesis of titanium dioxide nanoparticles in plasma discharge was carried out under ultrasonic cavitation. It was found that applied acoustoplasma method allows to synthesize nanosized particles of titanium dioxide with the controlled shape and narrow size distribution. Polymer composite materials based on synthesized nanoparticles of titanium dioxide and epoxy polymer have been obtained by the in situ method by curing with preliminary ultrasonic dispersing. The composition and structure of the obtained TiO2 polymer composite materials have been studied by scanning electron microscopy. The mechanical properties of the obtained film polymer composite materials were investigated to determine the tensile strength, elastic modulus and relative deformation. It was found that nanoparticles in optimal concentration (3%) lead to the reinforcement of obtained composite materials.
On a pseudo-periodicity in the elastodynamics
Authors: Kurdina S P , Gevorgyan H A 
Published: April 2022

Abstract
The periodic laws of motion of a real mechanism imply the periodicity of all dynamic characteristics of the mechanism during such a movement, including the elastic displacements of its constituent links. This statement covers the most difficult problem of the dynamics of an elastically deformable body. However the existing publications devoted to the study of flexible mechanisms do not mention the periodicity of elastic displacements of the links when the mechanisms move according to periodic laws. This article discusses the periodicity and pseudo-periodicity of the elastic displacements of the links using examples of calculations of the motion of a double pendulum and a slider–crank mechanism without taking into account dissipative forces.
Quadrature formulas for Cauchy-type integrals with the Cauchy kernel to a integer power and a Jacobi weight function with complex exponents
Authors: Amirjanyan H A , Sahakyan A V , Kukudzhanov A K 
Published: April 2022

Abstract
The paper presents quadrature formulas for hypersingular integrals of various orders. It is assumed that the density of these integrals is represented as a product of a function that satisfies the Hölder condition and a weight function of Jacobi orthogonal polynomials. In this case, the exponents of the weight function can be complex numbers, the real part of which is greater than -1. Numerical analysis of the dependence of the root-mean-square deviation of the quadrature formula of order 8 on the value of the hypersingular integral calculated using standard software packages is carried out for various complex values of the weight function exponents. For hypersingular integrals up to the fourth order inclusive, a numerical analysis of the convergence of quadrature formulas is carried out for certain complex values of the exponents of the weight function.
Modeling of self-healing of microcracks in the process of longitudinal electroplastic rolling
Authors: Kukudzhanov K V 
Published: April 2022

Abstract
Multiscale model to describe the process of self-healing of microcracks in thin metal sheets during longitudinal electroplastic rolling is developed. The simultaneous treatment of a mechanical load and a pulsed high-energy electromagnetic field on the sheet is assumed. Finite element modeling has shown that under certain conditions microcracks and micropores can self-heal partially in the working zone. Impact of external pulsed high-energy electromagnetic field leads to welding of the shores of microcracks by molten metal in their tops, while the length and volume of cracks decrease.
Contact problem for a piecewise-homogeneous plane with an interfacial crack under dry friction
Authors: Hakobyan V N , Hakobyan L V , Dashtoyan L L 
Published: April 2022

Abstract
The article considers the contact problem of indentation of an absolutely rigid stamp with dry friction into one of the edges of an interfacial finite crack located in a piecewise homogeneous elastic plane. The governing system of equations for the problem is derived in the form of a system of three singular integral equations with respect to the normal contact pressure under the stamp and dislocation components of the displacements of the crack edge points. The exact solution is constructed. The behavior of contact stresses near the end points of a crack is studied depending on the ratio of the elastic characteristics of heterogeneous materials of half-planes that formed a piecewise-homogeneous plane.
Formation of a hybrid of electroacoustic waves in piezoelectric layered composites
Authors: Avetisyan A S , Khachatryan V M , Mkrtchyan M H 
Published: April 2022

Abstract
Investigating the reflection and refraction of electroelastic waves at a plane interface without acoustic contact between two piezoelectric half-spaces of different textures, it was found that: (i)As a result of the incidence of a two-component electroelastic shear wave on the interface between the media, the same wave is reflected into the first half-space, and a three-component electroelastic plane strain wave is refracted into the second half-space. In the utmost cases, in layered inhomogeneous waveguide, a wave hybrid of electroacoustic waves is formed. This makes it possible to transmit along the boundary of non-acoustic contact of media a hybrid of electroacoustic surface waves of the Gulyaev-Bluestein type and Rayleigh type localized near this boundary. (ii)As a result of the incidence of a two-component electroelastic plane strain wave on the interface between the media, the same wave is reflected into the first half-space, and a three-component electroelastic shear wave is refracted into the second half-space. This also makes it possible to organize a hybrid of electroacoustic waves of elastic shear and plane deformation of the type of periodic electroelastic Floquet waves in a periodically transversely inhomogeneous piezoelectric composite. The conditions for the possible formation of the hybrid and the characteristics of their propagation in the layered composites of piezoelectrics of the hexagonal symmetry class 6mm and

6

¯

m2 are discussed.
Supersonic divergence of a panel with a free edge initially loaded in two directions tensile and compressive forces
Authors: Martirosyan S R 
Published: April 2022

Abstract
In the article, in a linear formulation, the problem of the static stability of a rectangular plate in a supersonic gas is investigated, initially loaded in two directions, respectively, stretched along the gas flow and compressed in the direction perpendicular to the gas flow velocity, under the assumption that the gas flow runs on its free edge. An analytical solution to the problem is obtained. The space of parameters of the “plate-flow” system was partitioned into areas of stability and static instability in the form of panel divergence and in the form of localized divergence. The corresponding critical velocities are found. The ratio of the stress coefficients characterizing the tensile and compressive forces, leading to the dominance of the stabilization effect, has been established. It is shown that compressive forces have an insignificant effect on the stability of sufficiently elongated plates, in comparison with tensile forces. The boundary value of the tensile stress coefficient is found, starting from which the elongated plates are stable at the beginning of the interval of supersonic velocities.
Fuel ignition delay in hydrogen diesel
Authors: Bunev V A , Korzhavin A A , Senachin A P , Senachin P K 
Published: April 2022

Abstract
A new mathematical model is considered for modeling the induction period of fuel self-ignition in a hydrogen diesel engine with high-pressure injection equipment. Reconstruction of the macrokinetic equation and numerical modeling of the process of self-ignition of fuel in a hydrogen diesel engine are carried out.
Formation features of benz(a)pyrene and nitrogen oxides when burning brown coal in boilers with liquid slag removal system
Authors: Elsukov V K , Latushkina S V 
Published: April 2022

Abstract
In the article, the authors examine the experience of burning Kansk-Achinsk coal (KAC) in the boilers of the BKZ-320-140PT type at the CHPP-6 in Bratsk. The article considers the results of the experiments carried out at two boilers (b.u.No.5 and No.7), where the organization of aerodynamic processes is significantly different. These results are presented as the dependences of the concentrations of nitrogen oxides (NOx) and benz(a)pyrene (BaP), as well as the content of combustibles in fly-ash (Cf) on several parameters simultaneously, namely, the boiler load, the number of working dust collecting systems, and excess air. The following conclusions have been drawn: 1) two parameters have the most significant effect on the amount of BaP emissions – the scheme of entering drying gases into the combustion chamber and the excess air in the combustion chamber; 2) there is a certain relationship between BaP emissions and the content of combustibles in fly-ash: a lower Cf value corresponds to the mode with a lower concentration of BaP. It follows that BaP emissions can be reduced by measures reducing chemical and mechanical underburning (q3 and q4), primarily the turbulization of flue gases. The formula is proposed that clarifies the values of BaP emissions during vortex combustion. It is shown that the formation of NOx is also significantly affected by the same parameters as the formation of BaP, as well as the load of the boiler. The effect of these parameters is explained. Various technological measures are proposed to reduce pollutant emissions comprehensively by providing vortex combustion in the boilers with both liquid and solid slag removal systems.
Cutoff limitation of left-hand polarization wave and candidates for further enhanced producing multicharged ions on ECRIS
Authors: Kato Y , Kubo W , Harisaki S , Anan M , Tsuda K , Sato K , Owada I , Maenaka T 
Published: April 2022

Abstract
Based on experimentally obtained plasma parameters in an electron cyclotron resonance (ECR) ion source (ECRIS) and theoretical considerations, it is turned out the essential factor that is currently presumed to define the increase in multicharged ion current in ECRIS is not simply the density limit of ordinary wave and right-hand cutoffs, but is also higher density one of left-hand cutoff. There are two response guidelines that can be considered to make it possible to overcome limitations, except for the conventional simply increasing the frequency and the magnetic field strength. One is advanced high-frequency resonance, i.e., upper-hybrid resonance (UHR), which is conversion from electromagnetic to electrostatic wave essentially without cutoff. The others are due to the introduction of lower frequency waves than ECR’s one, which has no density limit in a more essential sense. The latter is the introduction of lower-hybrid resonance (LHR) or ion cyclotron resonance (ICR). We will describe experimentally obtained plasma parameters, and will discuss these candidate applications.
Redefining plasma chambers for ECR Ion Sources: the IRIS structure
Authors: Mascali D. , Galatà A. , Gallo S. , Leonardi O. , Mauro G. S. , Naselli E. , Pidatella A. , Russo F. , Sorbello G. , Torrisi G. 
Published: April 2022

Abstract
One possible way to optimize microwave coupling and plasma confinement in Electron Cyclotron Resonance (ECR) Ion Sources is a revolutionary design strategy of plasma chambers, breaking the cylindrical symmetry. This contribution reports about the design and numerical validation of an innovative resonant cavity playing as plasma chamber of ECR ion sources. The new chamber, named IRIS (Innovative Resonators for Ion Sources), was argued starting from the 3D structure of the plasma and, therefore, fashioned to the twisting magnetic structure. The microwave launching scheme was radically changed as well, consisting of side-coupled slotted-waveguides with diffractive apertures smoothly matching the overall structure of the camera. This approach also enables a profound optimization of cooling systems and overall spaces in general (for gas feedings, oven systems, sputtering, etc.). Here we report on the conceptual study, electromagnetic design and PIC simulations of the electron heating in the novel resonant cavity, comparing results with those for standard (cylindrical) chamber, and also considering the impact of microwave feeding led by single aperture rectangular waveguides vs. waveguide-slotted antennas. Manufacture strategy, based on additive manufacturing techniques, will also be discussed.
Two-rod-antenna microwave injection system for production of circularly polarized microwaves in cylindrical ECRIS cavities
Authors: Philipp Alexandra , Molodtsova Maria , Ritter Erik 
Published: April 2022

Abstract
In the design of Electron Cyclotron Resonance Ion Sources (ECRIS) three topics generally need to be addressed: (i) The feed of a microwave to generate a plasma, (ii) the creation of a magnetic field guiding the charged particles, and (iii) the design of an ion extraction system. In this report, we concentrate on improvements of aspect (i), a new microwave injection system introduced to the Dresden ECRIS 2.45M, a permanent-magnet 2.45 GHz ECRIS, applied, e.g., for the production of proton currents in medical particle therapy. The improvements include the replacement of its one-rod antenna system by two rod antennas on one cross-sectional circle of the cylindrical ECRIS cavity positioned under an angle of 90° towards each other. Feeding two microwave signals with a relative phase shift of 90°, a right-hand circularly polarized wave can be created inside the cavity to efficiently heat the electrons. Basic considerations, simulations, and results from first experiments are presented.
New Commissioning Results of the MIST-1 Multicusp Ion Source
Authors: Winklehner Daniel , Conrad Janet , Smolsky Joseph , Waites Loyd , Weigel Philip 
Published: April 2022

Abstract
For the sterile neutrino experiment IsoDAR (Isotope Decay-At-Rest), we have developed a compact particle accelerator system delivering a 10 mA, continuous wave (cw) proton beam at 60 MeV to a neutrino production target. The accelerator comprises a compact isochronous cyclotron, an RFQ embedded in the cyclotron yoke, and an ion source. To reduce space charge effects during injection and acceleration, we are accelerating H+
2 instead of protons. To produce the needed cw H+
2 beam current of 10 mA (nominal) at the required purity and quality, we have built a new filament driven, multicusp ion source (MIST-1). Here we report commissioning results for long-time running at reduced power, demonstrating the feasibility of the design. Highlights include an H+
2 beam current density of ≈ 10 mA/cm2, ≈ 80% H+
2 fraction, and extrapolated emittances of 0.05 π-mm-mrad (RMS, normalized) after extraction. We also present high fidelity simulations that are in good qualitative and quantitative agreement with emittance measurements in our test beam line.
The AISHa ion source at INFN-LNS
Authors: Castro G. , Celona L. , Chines F. , Costanzo G. , Gammino S. , Leonardi O. , Malferrari L. , Massara A. , Maugeri C. , Neri L. , Odorici F. , Passarello S. , Reitano R. , Russo F. , Siliato D. 
Published: April 2022

Abstract
The Advanced Ion Source for Hadrontherapy (AISHa) is an ECR ion source operating at 18 GHz, developed with the aim of producing high intensity and low emittance highly charged ion beams for hadrontherapy purposes. Due to its unique peculiarities, AISHa is a suitable choice for industrial and scientific applications. In the framework of the INSpIRIT and IRPT projects, in collaboration with Centro Nazionale di Adroterapia Oncologica (CNAO), new candidates for cancer treatment (including metal ion beams) are being developed. Moreover, within the IONS experiment, AISHa will be the test-bench for the development of an innovative active plasma chamber designed to increase plasma confinement by changing plasma fluxes. OES technique will be also used to refine techniques of non-invasive plasma diagnostics. Finally, a dedicated setup is under realization to provide impinging beams and detection systems for target production in nuclear physics experiments.
Impurities Reduction Conditionings to Recover Best Beam Quality of J-PARC Cesiated RF-Driven H- Ion Source with New Parts Exposed to Plasma
Authors: Ueno Akira , Ohkoshi Kiyonori , Ikegami Kiyoshi , Oguri Hidetomo 
Published: April 2022

Abstract
For the J-PARC operations, only three plasma chambers (PCHs) of #7, #8 and #9PCHs among ten PCHs have been used since the transverse emittances of the beam produced with them are more superior than those with others for unknown reasons. However, the #7PCH beam emittances were enlarged by 16 % with a brand-new plasma electrode temperature control plate (PETCP) to solve the air leak at the VCR vacuum fitting. The impurities from the new parts exposed to the plasma seemed to cause the degradation. The beam with almost the best emittances was reproduced by #4PCH with a new PETCP after a new impurities reduction conditionings for 48 hours, in which the impurities produced by the plasma were reduced as small as possible by scanning both of 2-MHz-RF power and axial magnetic field in #4PCH.
RF power transfer efficiency of H ion sources: fluid modeling of accelerator source geometries
Authors: Briefi S , Zielke D , Fantz U 
Published: April 2022

Abstract
The plasma in RF driven negative hydrogen ion sources is sustained via inductive coupling with large power levels of up to 100 kW and low frequencies around 1 MHz. This leads to currents of around 100 A flowing over the RF coil and corresponding voltages in the kV range. The associated risk of arcing limits the reliability of the whole ion source. The required power level can be reduced via optimizing the RF power transfer efficiency η, which is typically only in the range of 50 to 60% for H- sources used for neutral beam injection systems. In order to study the optimization of η systematically, a self-consistent fluid model has been set up and successfully validated with experimental measurements at the BATMAN Upgrade test bed. For H- sources applied at particle accelerators, no experimental measurements of η are available so far. In order to gain a first insight into the RF power transfer efficiency of these sources, exemplary simulations were carried out with the fluid code. The simulated plasma parameters are in good agreement with results from OES measurements. η shows an increasing trend with larger source radius and a virtually constant value with increasing RF power. For benchmarking these first results, dedicated measurements at an accelerator source setup are inevitable.
Beam instability in the vicinity of beam extraction region of negative ion source
Authors: Nagaoka K. , Nakamoto R. , Sasaki T. , Hamajima T. , Nakano H. , Ikeda K. , Fujiwara Y. , Osakabe M. , Takeiri Y. , Tsumori K. 
Published: April 2022

Abstract
Beam instability in the presheath region of negative ion beam extraction is investigated in theoretically and experimentally. The linear stability analysis shows that the beam instability is unstable due to coupling between positive ion flow and negative ion flow. On the other hand, no clear activity can be seen in the experiment in the frequency range predicted by the theory. The beam instability in the presheath region of negative ion beam extraction may not cause the degradation of the beam focusing because of collisional damping and/or Landau damping.