bluuebunny/crossref_metadata_2025_split huggingface dataset:
Looping pendulum: theoretical and experimental studies
Authors: Wen Qinghao , Huang Xiucai , Zhang Yansheng , Ong Etienne 
Published: September 2020

Abstract
This work focuses on exploring the phenomenon of looping pendulum proposed by ‘International Young Physicists’ Tournament in 2019, specifically, the various types of loops observed and the physical conditions for a loop to be successful. Firstly, we establish a theoretical model for three distinct stages of the motion observed in the phenomenon, i.e. slipping, non-slipping, and pulling phenomena. We then construct a numerical algorithm for simulation studies so as to predict the looping trajectory, which is significantly influenced by the mass ratio between the masses, the initial release angle of the small mass and the initial distance between the small mass and the tangential point on the rod. Phase plots, which illustrate how varying some of these parameters will affect the type of loop produced, are generated. The theoretical looping trajectories and phase plots are verified experimentally. A qualitative analysis of the common trajectories observed and the successful trends in the phase plots are presented to provide further insights on the physics of this phenomenon. The findings presented in this paper reveal some properties of the looping pendulum and help us to gain a better understanding of its physical behavior.
Interatomic resonant Auger effect in N2O
Authors: Deinert Sascha , Schrodt Alexander , Hartmann Gregor , Achner Alexander , Artemyev Anton N , Ehresmann Arno , Hans Andreas , Ilchen Markus , Glaser Leif , Scholz Frank , Seltmann Jörn , Viefhaus Jens , Demekhin Philipp V , Knie André 
Published: September 2020

Abstract
The interatomic resonant Auger effect in N2O is investigated experimentally and theoretically. We observe variations of the ratio between the yields of 1s-photoionization of the central and terminal nitrogen atom in the photon energy range across the O 1s → π* excitation. The present ab initio calculations of electronic structure and dynamics attribute these variations to the Fano interference between the direct N 1s-photoionizations and the resonant O 1s → π* excitation followed by Auger decays into the respective core–shell continua. The theory reveals that this interatomic core–hole-transfer effect is governed entirely by an energy transfer mechanism, and not by charge transfer.
Electron scattering studies of BF and BF2
Authors: Gupta Dhanoj , Choi Heechol , Song Mi-Young , Singh Suvam , Antony Bobby , Chakrabarti Kalyan , Yoon Jung-Sik , Tennyson Jonathan 
Published: September 2020

Abstract
The present article reports calculated elastic, differential, momentum transfer and excitation cross section for electron scattering from BF and BF2 radicals using the ab initio R-matrix method. The calculations are performed with complete active space—configuration interaction and static exchange models for both targets to yield scattering cross sections and resonance parameters. Elastic and momentum transfer cross sections are also calculated using the spherical complex optical potential method to cover a wide energy range. The total ionization cross section is also reported from ionization threshold to 5 keV. The calculated cross sections for these neutral species are important for BF3 plasma and are reported for the first time to the best of our knowledge except ionization.
Comparative studies of the degrees of orientation of CO molecules pumped by intense femtosecond two-color pulses based on high-order harmonic generation and Coulomb explosion imaging
Authors: Minemoto Shinichirou , Komatsubara Wataru , Sakai Hirofumi 
Published: September 2020

Abstract
With an intense femtosecond two-color pulse optimized for the generation of even-order harmonics from CO molecules, we directly measure the actual degrees of orientation by utilizing the Coulomb explosion imaging technique with appropriate probe polarization. We find that the macroscopic orientation of CO molecules is negligible even when significant even-order harmonics are observed. This finding shows that the generation of even-order harmonics cannot be ascribed to the macroscopic orientation of CO molecules. The rotational wave packet of CO molecules created with an intense femtosecond two-color pulse is thought to be in an uninvestigated quantum state, which cannot be explained by the theoretical model based on the Born–Oppenheimer approximation, without inversion symmetry at any of the three steps of high-order harmonic generation, leading to the generation of even-order harmonics.
Chaotic dynamics of a non-Hermitian kicked particle
Authors: Huang Kai-qian , Wang Jiaozi , Zhao Wen-Lei , Liu Jie 
Published: September 2020

Abstract
We investigate both the classical and quantum dynamics of a kicked particle with

P
T

symmetry. In chaotic situation, the mean energy of the real parts of momentum linearly increases with time, and that of the imaginary momentum exponentially increases. There exists a breakdown time for chaotic diffusion, which is obtained both analytically and numerically. The quantum diffusion of this non-Hermitian system follows the classically chaotic diffusion of Hermitian case during the Ehrenfest time, after which it is completely suppressed. Interestingly, the Ehrenfest time decreases with the decrease of effective Planck constant or the increase of the strength of the non-Hermitian kicking potential. The exponential growth of the quantum out-of-time-order correlators (OTOC) during the initially short time interval characterizes the feature of the exponential diffusion of imaginary trajectories. The long time behavior of OTOC reflects the dynamical localization of quantum diffusion. The dynamical behavior of inverse participation ratio can quantify the

P
T

symmetry breaking, for which the rule of the phase transition points is numerically obtained.
A rotating machinery fault diagnosis method using composite multiscale fuzzy distribution entropy and minimal error of convex hull approximation
Authors: Zhao Xianzhu , Cheng Junsheng , Wang Ping , Yang Yu 
Published: September 2020

Abstract
Rotating machinery plays an increasingly crucial role in mechanical systems. For its normal operation, a novel fault diagnosis method is proposed in this paper, using composite multiscale fuzzy distribution entropy (CMFDE) and minimal error of convex hull approximation (MECHA). In this paper, CMFDE is utilized to extract essential information and measure time series complexity for vibration signals. Results indicate the CMFDE has less information loss and better stability. Then, to fulfill the classification tasks, the first several main features obtained by principal components analysis are fed into the proposed MECHA-based classifier. Results show MECHA has better classification performance. Using the laboratory data, we validate the feasibility and superiority of the proposed fault diagnosis method through two cases consisting of different fault types or fault severity degrees.
Recyclable free-polymer transfer of nano-grain MoS2 film onto arbitrary substrates
Authors: Woo Gunhoo , Kim Hyeong-U , Yoo Hocheon , Kim Taesung 
Published: September 2020

Abstract
Clean transfer of transition metal dichalcogenides (TMDs) film is highly desirable, as intrinsic properties of TMDs may be degraded in a conventional wet transfer process using a polymer-based resist and toxic chemical solvent. Residues from the resists often remain on the transferred TMDs, thereby causing a significant variation in their electrical and optical characteristics. Therefore, an alternative to the conventional wet transfer method is needed—one in which no residue is left behind. Herein, we report that our molybdenum disulfide (MoS2) films synthesized by plasma-enhanced chemical vapor deposition can be easily transferred onto arbitrary substrates (such as SiO2/Si, polyimide, fluorine-doped tin oxide, and polyethersulfone) by using water alone, i.e. without residues or chemical solvents. The transferred MoS2 film retains its original morphology and physical properties, which are investigated by optical microscopy, atomic force microscopy, Raman, x-ray photoelectron spectroscopy, and surface tension analysis. Furthermore, we demonstrate multiple recycling of the resist-free transfer for the nano-grain MoS2 film. Using the proposed water-assisted and recyclable transfer, MoS2/p-doped Si wafer photodiode was fabricated, and the opto-electric properties of the photodiode were characterized to demonstrate the feasibility of the proposed method.
Animal tissue-based quantitative comparison of dual-energy CT to SPR conversion methods using high-resolution gel dosimetry
Authors: Niepel K B , Stanislawski M , Wuerl M , Doerringer F , Pinto M , Dietrich O , Ertl-Wagner B , Lalonde A , Bouchard H , Pappas E , Yohannes I , Hillbrand M , Landry G , Parodi K 
Published: September 2020

Abstract
Dual-energy computed tomography (DECT) has been shown to allow for more accurate ion therapy treatment planning by improving the estimation of tissue stopping power ratio (SPR) relative to water, among other tissue properties. In this study, we measured and compared the accuracy of SPR values derived using both dual- and single-energy CT (SECT) based on different published conversion algorithms. For this purpose, a phantom setup containing either fresh animal soft tissue samples (beef, pork) and a water reference or tissue equivalent plastic materials was designed and irradiated in a clinical proton therapy facility. Dosimetric polymer gel was positioned downstream of the samples to obtain a three-dimensional proton range distribution with high spatial resolution. The mean proton range in gel for each tissue relative to the water sample was converted to a SPR value. Additionally, the homogeneous samples were probed with a variable water column encompassed by two ionization chambers to benchmark the SPR accuracy of the gel dosimetry. The SPR values measured with both methods were consistent with a mean deviation of 0.2%, but the gel dosimetry captured range variations up to 5 mm within individual samples.
Across all fresh tissue samples the SECT approach yielded significantly greater mean absolute deviations from the SPR deduced using gel range measurements, with an average difference of 1.2%, compared to just 0.3% for the most accurate DECT-based algorithm. These results show a significant advantage of DECT over SECT for stopping power prediction in a realistic setting, and for the first time allow to compare a large set of methods under the same conditions.
A review of simulation codes and approaches for radiation chemistry
Authors: Plante Ianik 
Published: September 2020

Abstract
Historically, the field of radiation chemistry began shortly after the discovery of radioactivity, and its development has been closely related to discoveries in other related fields such as radiation and nuclear physics. Radiolysis of water and radiation chemistry have been very important in elucidating how radiation affects living matter and how it induces DNA damage. Nowadays, we recognize the importance of chemistry to understanding the effects of radiation on cells; however, it took several decades to obtain this insight, and much is still unknown. The radiolysis of water and aqueous solutions have been the subject of much experimental and theoretical research for many decades.
One important concept closely related to radiation chemistry is radiation track structure. Track structure results from early physical and physicochemical events that lead to a highly non-homogenous distribution of radiolytic species. Because ionizing radiation creates unstable species that are distributed non-homogenously, the use of conventional reaction kinetics methods does not describe this chemistry well. In recent years, several methods have been developed for simulating radiation chemistry. In this review, we give a brief history of the field and the development of the simulation codes. We review the current methods used to simulate radiolysis of water and radiation chemistry, and we describe several radiation chemistry codes and their applications.
Deep level defects and their instability in PLD-grown IGZO (In2Ga2Zn5O11) thin films studied by thermally stimulated current spectroscopy
Authors: Wang Buguo , Look David , Anders Jason , Leedy Kevin , Schuette Michael 
Published: September 2020

Abstract
InGaZnO (IGZO) is an excellent semiconductor material for thin-film transistors (TFTs) used in direct-current and radio-frequency (RF) switching applications, especially since it can be grown at low temperatures on a wide variety of substrates. IGZO thin films with a composition of InGaZnO4 have been deposited and used as channel layers in TFTs for many applications to date; however, IGZO compositions can also be easily changed to vary their properties. These different compositions of IGZO may have different defect properties. In this study, we report the growth of IGZO with composition of In2O3:Ga2O3:5ZnO (In2Ga2Zn5O11) by pulsed laser deposition (PLD) and its electronic defects studied by thermally stimulated current (TSC) spectroscopy. It was found that the as-grown sample has a DC activation energy of 0.62 eV, and four major traps with activation energies between ∼0.16–0.50 eV and one at ∼0.90 eV. Electrical properties and the deep traps of PLD-grown IGZO thin film were found to be varied by post-processing conditions such as thermal history and measurement conditions such as the bias and light exposure applied to the samples. The instabilities induced by these conditions can be explained by structural and stoichiometric features—the ZnO4 tetrahedra and GaO6 octahedra in the structure may become distorted, caused by oxidation or reduction, so that the different defect states could be changed and/or lattice energy variations from the distortion can be observed. This work demonstrates that current-based trap emission, such as that associated with TSC, can effectively reveal electronic defects in highly-resistive semiconductor materials, especially those that are not amenable to capacitance-based techniques, such as deep-level transient spectroscopy, and provide an effective manner to study the trap instabilities in IGZO.
Decreasing the V
th shift of InGaZnO thin-film transistors under positive and negative bias stress using SU-8 as etch-stop and passivation layer
Authors: Lopez Castillo M A , Toledo-Guizar P G , Andraca Adame J A , Garcia R , Hernandez Cuevas F J , Aleman M , Hernandez-Como N 
Published: September 2020

Abstract
In order to expand the InGaZnO (IGZO) technology to several applications other than displays, including integrated circuits with certain complexity, it is necessary to mitigate the V
th shift under bias stress. For this purpose, the use of a passivated semiconductor channel has demonstrated its effectiveness in improving the V
th reliability. In this work, staggered bottom gate IGZO thin-film transistors were fabricated using a 450 nm SU-8 2000.5 film as a passivation and etch-stop layer. The thin-film transistors (TFTs) were fabricated by a full lithography process and the SU-8 film determined the maximum processing temperature of 200 °C. Positive and negative bias stress were performed during 1200 s on 150 μm/40 μm (W/L) TFTs stressed at low field (2 MV cm−1) and high field (4 MV cm−1) leading to a maximum V
th shift of 0.12 V and −0.38 V, respectively. The negative V
th shift was associated to an undesired mechanism dominated by hydrogen migration. The spin coated SU-8 passivation layer demonstrated higher device stability and it can be also used for future interconnection between transistors.
A Kretschmann setup at acoustic frequencies for studying molecular vibration
Authors: Simone Giuseppina , de Ruijter Pim 
Published: September 2020

Abstract
In this study, simultaneous measurement of surface plasmon resonance (SPR) and surface enhanced Raman scattering (SERS) on flat metallic surfaces was demonstrated in a setup based on the Kretschmann configuration at acoustic frequency. This asset facilitates matching the photon and the surface plasmon polaritons wavevectors by tunneling the photon in the total internal reflection geometry and we demonstrate the compensation for the absence of hotspots typical on rough surfaces. The optomechanical asset allows detecting the two signals and prevents their interference. Experimental and numerical analyses were done for characterizing the two signals. The results emphasize the enhancement of the electromagnetic field at the surface, which provides high sensitivity for detecting the signals coming from the Raman probe molecules such as Congo red and thiols such as cysteamine. The combination of simultaneous SPR–SERS microspectroscopy at low frequencies opens up interesting prospects that facilitate experimental conditions using standard SPR setups, with a dramatic reduction in sensor cost.
Optical and dielectric spectroscopic analysis of SmMn2O5
Authors: Ahmad J , Bukhari S H , Khan J A , Jamil M T , Nissar U , BiBi S , Sultan T 
Published: September 2020

Abstract
Polycrystalline SmMn2O5 has been synthesized by using sol-gel auto combustion tecnique. X-ray diffraction (XRD) pattern reflects the single phase formation of orthorhombic structure with Pbam space group. In the frequency range of (30–1000 cm−1) reflectivity spectrum reveals the 14 infrared active phonons out of 36, which are already pridicted theoretically. We have estimated the optical energy band gap (E
g
) ≃ 1.5 eV from UV–visible absorption spectrum. Temperature dependent (293-533 K) DC electrical characterization up to 40 V suggests semiconducting nature of the material. The temperature dependent impedance spectroscopy within a broader frequency range of (20 Hz—3 GHz) shows decreasing behavior of dielectric constant and tangent loss while AC conductivity increasing with the rise in frequency and temperature suggest the strong frequency dispersion and relaxational behavior of the material. The activation energy calculation from AC conductivity is in good agreement with semiconducting material energy band gap.
An algorithm for determining the state of a non-stationary dynamic system for assessing fire safety control in an enterprise by the method of integrated indicators
Authors: Masaev S N , Minkin A N , Edimichev D A 
Published: September 2020

Abstract
Analysis of the scientific literature showed that a lot of work is devoted to assessing the effectiveness of fire safety management in an enterprise. It is worth noting that today there is no universal method for the integrated assessment of fire safety management, taking into account the interconnectedness of all enterprise subsystems and the influence of environmental factors. One of the original approaches to assessing the effectiveness of the fire safety management system is the method of integral indicators. The method of integral indicators is used in the algorithm for analyzing the state of a dynamic non-stationary system for assessing fire safety management in an enterprise. The algorithm is implemented in the author’s complex of programs described in the text of the article. In the simulation, an analysis of 1.2 million values is performed on a well-studied economic object with the spaces identified at each time step: actual data, control and environmental parameters. In the experiment, the basic mode of operation of the enterprise does not contain the implementation of a fire safety management strategy. The research showed significant changes in the values of the integral indicator characterizing the state of the enterprise during the implementation of the fire safety management system at the enterprise.
Explore the feasibility of fabricating pure copper parts with low-laser energy by selective laser melting
Authors: Lingqin Xia , Guang Chen , Luyu Zheng , Pan Lu 
Published: September 2020

Abstract
Pure copper is widely used for complex shapes, high thermal conductivity and good conductivity parts, such as heat exchangers, welding nozzles, injection molds, and various conductive parts. However, traditional manufacturing techniques are difficult to design complex pure copper parts into the most effective thermal and conductive structure. Selective Laser melting(SLM) can fabricate parts with complex shapes directly. However, due to the characteristics of easy oxidation, high optical reflectivity and high thermal conductivity, 3D printing pure copper by SLM is extremely challenging. In this study, the feasibility of fabricating pure copper by low-laser energy was studied by both numerical simulation and printing experiments, and the characteristics of the molten pool (molten pool structure, temperature flow and velocity flow) were studied. The results showed that due to its high thermal conductivity, heat spread out quickly in the molten pool, temperature rise rate and cooling rate reached as high as 1.36 × 107 K S−1, 2.99 × 105 K S−1 respectively. And it took only about 1.7 × 10–4 S for the process time of powder melting and solidification. Additionally, by reducing the particle size, the absorption rate for pure copper was improved, pure copper parts were successfully fabricated with low-laser energy: laser power 500 W, hatching space 0.07 mm, layer thickness 0.03 mm, laser scanning velocity 2500 mm s−1.
Stabilization of an iridium oxygen evolution catalyst by titanium oxides
Authors: Kasian Olga , Li Tong , Mingers Andrea M , Schweinar Kevin , Savan Alan , Ludwig Alfred , Mayrhofer Karl 
Published: September 2020

Abstract
The anodic oxygen evolution reaction (OER) has significant importance in many electrochemical technologies. In proton exchange membrane water electrolyzers it plays a pivotal role for electrochemical energy conversion, yet sluggish kinetics and the corrosive environment during operation still compel significant advances in electrode materials to enable a widespread application. Up-to-date Iridium is known as the best catalyst material for the OER in acidic media due to its relatively high activity and long-term stability. However, scarcity of iridium drives the development of strategies for its efficient utilization. One promising way would be the formation of mixtures in which the noble catalyst element is dispersed in the non-noble matrix of more stable metals or metal oxides. A promising valve metal oxide is TiOx, yet the degree to which performance can be optimized by composition is still unresolved. Thus, using a scanning flow cell connected to an inductively coupled plasma mass spectrometer, we examined the activity and stability for the OER of an oxidized Ir–Ti thin film material library covering the composition range from 20–70 at.% of Ir. We find that regardless of the composition the rate of Ir dissolution is observed to be lower than that of thermally prepared IrO2. Moreover, mixtures containing at least 50 at.% of Ir exhibit reactivity comparable to IrO2. Their superior performance is discussed with complementary information obtained from atomic scale and electronic structure analysis using atom probe tomography and x-ray photoelectron spectroscopy. Overall, our data shows that Ir–Ti mixtures can be promising OER catalysts with both high activity and high stability.