bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel membrane-cavity-grating (MCG) meta-structure for enhancing low-frequency sound absorption
Authors: Wang Li Bo , Wu Jiu Hui , Lei Yun Zhong , Niu Jia Min , Huang Yao , Liu Chong Rui 
Published: July 2022

Abstract
For resonant-type absorbers with a back cavity, the improvement of low-frequency sound absorption always depends on increasing the back cavity depth, which hinders its practical application. To realize satisfactory sound absorption performance in low-frequency range (<500 Hz) while keeping the depth of the back cavity unchanged, a membrane-cavity-grate (MCG) meta-structure is proposed. The specific physical mechanisms for sound absorption are analyzed from acoustic impedance and energy dissipate perspectives. Furthermore, some key parameters of the MCG unit cell are investigated to optimize the sound absorption performance. On this basis, a meta-structure with six-unit-cell is proposed. Compared with the structure without the grating, the meta-structure can realize 20% improvement of the average sound absorption coefficient in the range from 300 Hz to 700 Hz with the back cavity depth and the structure size unchanged, which is verified by the high consistency between finite element simulation and acoustic impedance tube experiment results. This work provides a potential avenue for low-frequency noise reduction structure design.
Acoustic Gaussian-Airy beams
Authors: Chen Xizhou , Ding Suyu , Wei Qinran , Tu Juan , Guo Xiasheng , Zhang Dong 
Published: July 2022

Abstract
Acoustic Airy beams as non-diffractive beams possess self-bending, self-healing, and non-diffraction virtues and are expected to have great potential in applications like ultrasonic imaging. Here an analytical theory is provided for Gaussian modulated Airy (gAiry) acoustic beams. It is revealed through numerical calculations and finite element simulations that gAiry beams inherit the merits mentioned above of standard Airy beams. In theoretically predicted and more practical cases where sources of limited apertures generate beams, reduction of side lobes is found in gAiry fields, while bilateral focusing using a pair of beams shows improved field features when compared with focused Airy fields. The theories and observations here can help deploy gAiry beams in applications.
Charge transfer and metal–insulator transition in (CrO2)
m
/(TaO2)
n
superlattices
Authors: Shan Wanfei , Luo Weidong 
Published: July 2022

Abstract
Various interfacial emergent phenomena have been discovered in tunable nanoscale materials, especially in artificially designed epitaxial superlattices. In conjunction, the atomically fabricated superlattices have exhibited a plethora of exceptional properties compared to either bulk materials separately. Here, the (CrO2)
m
/(TaO2)
n
superlattices composed of two lattice-matched metallic metal oxides are constructed. With the help of first-principle density-functional theory calculations, a computational and theoretical study of (CrO2)
m
/(TaO2)
n
superlattices manifests the interfacial electronic properties in detail. The results suggest that emergent properties result from the charge transfer from the TaO2 to CrO2 layers. At two special ratios of

1
:
1

and

1
:
2

between m and n, the superlattices undergo metal-to-insulator transition. Additionally, the bands below the Fermi level become narrower with the increasing thickness of the CrO2 and TaO2 layers. The study reveals that the electronic reconstruction at the interface of two metallic materials can generate interesting physics, which points the direction for the manipulation of functionalities in artificial superlattices or heterostructures within a few atomic layers.
Coordination compound-derived Fe4N/Fe3N/Fe/CNT for efficient electrocatalytic oxygen evolution: a facile one-step synthesis in the absence of extra nitrogen source
Authors: Cui Lei Lei , Leng Wan Cong , Liu Xing , Gong Yun 
Published: July 2022

Abstract
By annealing an Fe(III)–coordination compound (Fe–CC), [FeCl3(Hbta)2] (Hbta = benzotriazole) in the presence of a carbon nanotube precursor (PCNT) template, an Fe4N/Fe3N/Fe/CNT heterostructure was successfully synthesized without an extra nitrogen source. The decomposition of the Hbta in Fe–CC under high-temperature annealing can produce carbon sheets and reduced graphene oxide (rGO), and the presence of CNTs can alleviate the stacking of the in situ-generated carbon materials. Meanwhile, iron nitride nanoparticles (NPs) can be anchored on the carbon sheets, and the anchoring effect efficiently prevents the agglomeration of NPs and increases the amount of active catalytic sites for the oxygen evolution reaction (OER). Fe4N/Fe3N/Fe/CNT shows an excellent OER activity with a Tafel slope of 63 mV dec−1 as well as overpotentials of 121 (η
10) and 275 mV (η
100) at 10 and 100 mA cm−2, respectively — far exceeding commercial RuO2 and other catalysts. Density functional theory calculations show that the excellent OER performance of Fe4N/Fe3N/Fe/CNT is associated with the Fe4N/Fe3N heterojunction, which can improve the electron conductivity and boost the electron transfer from N to Fe. The Fe4N/Fe3N/Fe/CNT catalyst exhibits long-term OER activity during 100 h of electrolysis at 20 mA cm−2. This is related to the dual coatings of the in situ-generated thin carbon shell and few-layered rGO on the surface of the iron nitride NPs, which can protect the fast leaching of iron nitride during the OER process. Furthermore, the effects of the annealing temperature, the PCNT template and the heating rate on the calcined products were investigated.
Inverse metal-assisted chemical etching of germanium with gold and hydrogen peroxide
Authors: Lidsky D , Cain J M , Hutchins-Delgado T , Lu T M 
Published: July 2022

Abstract
Metal-assisted chemical etching (MACE) is a flexible technique for texturing the surface of semiconductors. In this work, we study the spatial variation of the etch profile, the effect of angular orientation relative to the crystallographic planes, and the effect of doping type. We employ gold in direct contact with germanium as the metal catalyst, and dilute hydrogen peroxide solution as the chemical etchant. With this catalyst-etchant combination, we observe inverse-MACE, where the area directly under gold is not etched, but the neighboring, exposed germanium experiences enhanced etching. This enhancement in etching decays exponentially with the lateral distance from the gold structure. An empirical formula for the gold-enhanced etching depth as a function of lateral distance from the edge of the gold film is extracted from the experimentally measured etch profiles. The lateral range of enhanced etching is approximately 10–20 μm and is independent of etchant concentration. At length scales beyond a few microns, the etching enhancement is independent of the orientation with respect to the germanium crystallographic planes. The etch rate as a function of etchant concentration follows a power law with exponent smaller than 1. The observed etch rates and profiles are independent of whether the germanium substrate is n-type, p-type, or nearly intrinsic.
Bouncing up and down an incline
Authors: Cross Rod 
Published: July 2022

Abstract
Experimental results are presented concerning the motion of a ball that bounces up an incline a few times then bounces back down again. The number of bounces up the incline is typically small since the speed of the ball in a direction parallel to the incline decreases rapidly, not only during each bounce but also while the ball is in the air. The ball heads back down the incline when it is incident at right angles to the incline.
Experimental Didactic Kit for teaching resistors, capacitors and RC timing circuits
Authors: Schiavon G J , Santos O R , Batista M C , Braga W S , Bratti V M 
Published: July 2022

AbstractIn this work, an alternative Experimental Didactic Kit for teaching resistors, capacitors andRCtiming circuits was developed, using the Arduino platform technology, which is composed of a microcontroller and peripherals, due to the easy access to available teaching materials, enabling the reproduction of the prototype in the future by people with little knowledge in the area, and because it is an open-source platform. In addition, it allows visually impaired students to participate in the activity. The experimental results are in good agreement with the theoretical ones. Moreover, it can be used as a great option to study resistors and capacitors in general. It also allows for a more detailed work, presenting an advantage in the teaching-learning process when compared to the traditional method, awakening in the student the interest in the study of Physics. We believe that this material is very useful in physics classes, being a great option for other teachers, aiming to improve students’ knowledge and skills.
Development of homogeneous and high-performance REBCO bulks with various shapes by the single-direction melt growth (SDMG) method
Authors: Motoki Takanori , Sasada Rempei , Tomihisa Takuma , Miwa Masaya , Nakamura Shin-ichi , Shimoyama Jun-ichi 
Published: July 2022

Abstract
We have developed a single-direction melt growth method in which REBCO melt-textured bulks grow only vertically from a seed plate utilizing the difference in peritectic temperatures of REBCO. Entirely c-grown YBCO, DyBCO and GdBCO bulks with various sizes and shapes were successfully fabricated with high reproducibility. Disk-shaped bulks showed high trapped fields with almost concentric field distributions, reflecting homogeneous and boundaryless bulk structures. In particular, a YBCO bulk with a 32 mm diameter trapped a high field more than 1 T at 77 K. Furthermore, rectangular and joined hexagonal REBCO bulks were successfully fabricated, showing designed field-trapping distributions reflecting their shapes through well-connected superconducting joints among bulks.
Welding analysis and optimization of ultra- sonic welding in HDPE-5%PBI composite by CODAS decision-making approach
Authors: Ramesh M , Panneerselvam K 
Published: July 2022

Abstract
Engineering plastics are increasingly being used in structural and non-structural applications. As the need for plastics grows, so do the joining requirements. Ultrasonic welding is one of the favoured processes for polymer composites among numerous approaches, especially for bonding plates, automotive panel boards and couplings due to its joint quality and low cost. The High-density polyethylene (HDPE) matrix was reinforced with 5 wt% of polybenzimidazole (PBI) fibre by twin screw extrusion process and welding samples were prepared using injection moulding. In this study, Ultrasonic welding was used to connect 4 mm-thick lapped HDPE-5wt% PBI composites. Taguchi-based L27 orthogonal array was employed for experiments to study the lateral shear strength (LSS) and Shore-D-Hardness for the input parameters (i) weld duration (30,45 and 60 ms), (ii) frequency (19,20 and 21 Hz) and (iii) horn pressure (1.5, 2 and 2.5 MPa). The relevance of the parameters affecting shear strength and hardness of weld was studied using analysis of variance (ANOVA). ANOVA results shows the frequency (Hz) and weld time (ms) had contributed 32.4% and 31.6% in determining shear strength and weld time (ms) contributes 45% for shore D hardness. The ultrasonic welding process was carried out, and the multi-criteria decision-making (MCDM) approach was used to optimise the process parameters. From CODAS assessment the relative evaluation score of 2.444 was achieved by the twenty fifth experiment having the input parameters (IP) at 60 ms welding time, frequency of 21 Hz and pressure at 2.5 MPa considering each output factor with an entropy of 0.5. Fractography and weld morphology of welded joints were investigated using scanning electron microscope (SEM).
Anisotropy of exchange and Dzyaloshinskii-Moriya interactions effects on the stabilization of Néel-type skyrmions
Authors: Li W C , Liu Z Q , Chen J Y , Xie D , Yao X W , Deng Z X 
Published: July 2022

Abstract
In this work, the effect of uniaxial stress on the stability of magnetic skyrmion is studied by use of Monte Carlo simulations. The classical Heisenberg model with anisotropic exchanges and Dzyaloshinskii-Moriya interactions is applied to correlate the stress behavior. We calculate magnetization M and skyrmion number Q to estimate the phase transition points, use the spin configurations and their Fourier transform to determine the region of skyrmion state. The h − T phase diagram show the area of skyrmion state is larger with stress than without stress. These results are interpreted qualitatively by the energy competitions between Zeeman, exchanges and Dzyaloshinskii-Moriya interactions. The simulated results suggest that anisotropy induced by uniaxial stress can stabilize the skyrmion phase.
Porous cage-like microfiber of fly ash magnetic powder (CMS)/polyaniline (PANI) composites with absorption properties
Authors: Li Dawei , Tao* Yulun , Li Shuo , Wu Yuannan , Wang Chaoran , Lv Yinru , Zhu Guisheng , Qiu Haifang , Liu Xin , Chen Chen 
Published: July 2022

Abstract
In order to recycling adsorbent of wastewater, magnetic adsorbents with recycling properties were prepared by fly ash magnetic powder (CMS)-doped polyaniline microfiber composites (CMS/PANI microfiber). The cheap fly ash magnetic powder is obtained from industrial solid waste fly ash. XRD patterns of CMS/PANI microfiber shows that the peaks at 30° are corresponding to the magnetite in CMS. SEM images shows that CMS/PANI fibrous winding structures forming a porous cage, where microfiber have the diameter of 60 nm and the length of 2–3 um. EDS spectra indicated that the magnetic dots monodispersed on the surface of every root of microfiber. BET surface areas of PANI microfiber and CMS/PANI microfiber are 36.42 m2 g−1 and 25.75 m2 g−1, respectively. The different wastewater samples has been used including congo red(CR), methyl orange(MO) and halogenated element ions solutions. The maximum adsorption amounts of CR and MO were 324.68 mg g−1 and 212.3 mg g−1, respectively. Interestingly, the CMS/PANI nanofibre material still adsorbs very well to other ionic wastewaters. The magnetic adsorbent achieves a sorption rate of 70% for Ca2+ containing wastewater under certain conditions. The magnetic adsorbent exhibited 48% adsorption of Cl− and over 90% adsorption of F−, Br− and I−. After six cycles of magnetic separation, the adsorption rate was still above 96%. The adsorption curves and equation fits show that the adsorption process is consistent with the langmuir isotherm model and the quasi-secondary kinetic model.
Development of complexity induced frameworks for charged cylindrical polytropes
Authors: Khan Shiraz , Mardan S.A. , Rehman M.A. 
Published: July 2022

Abstract
The main theme of this work is the development of complexity induced generalized
frameworks for static cylindrical polytropes. We consider two different definitions of generalized
polytopes with charged anisotropic inner fluid distribution. A new methodology based on complexity
factor for the generation of consistent sets of differential equations will be presented. We
conclude our work by carrying out graphical analysis of developed frameworks.
Brane inflation driven by an arctan potential: CMB constraints and reheating
Authors: Neves R.M.P. , Santos da Costa S. , Brito F.A. , Alcaniz J.S. 
Published: July 2022

Abstract
We investigate the early universe evolution in the context of brane inflation driven by a supergravity-inspired arctan potential. We performed a slow-roll and a semi-analytical reheating analyses and obtained constraints on the inflationary parameters in agreement with Planck 2018 data. We also employed a Markov Chain Monte Carlo analysis to perform a parameter estimation of the cosmological parameters, obtaining results in good agreement with the currently available cosmic microwave background and baryon acoustic oscillation data. This work establishes the general theoretical predictions of the arctan model, with the results of the statistical analysis corroborating its observational viability.
Influence of injected signal polarization on SBS, SRS, spectral broadening, and self-pulsing properties in high-power fiber amplifier
Authors: Wang Yanshan , Peng Wanjing , Feng Yujun , Wang Jue , Wang Yao , Yang Xiaobo , Ke Weiwei , Sun Yinhong , Ma Yi , Gao Qingsong , Zhu Rihong , Tang Chun 
Published: July 2022

Abstract
In this paper, we construct a narrow-linewidth amplifier based on polarization-maintaining (PM) fiber, which can be injected by a fiber oscillator seed or white noise signal phase-modulated seed. The stimulated Brillouin scattering (SBS), SRS, spectral broadening, self-pulsing properties of the fiber amplifier when its’ injected signal is 0° or 45° relative to the slow axes of the PM fiber are studied. It is indicated that when the injected signal is launched at 45° relative to the slow axes, the nonlinear effects are significantly suppressed compared with the case of the injected signal is launched parallel to the slow axis. The spectral broadening rate is reduced from 0.14 pm W−1 to 0.0747 pm W−1, the ratio of Raman to laser peak intensity is increased from 20 dB to 30 dB, the SBS threshold is increased by >24%, and the self-pulsing threshold is increased by 28.7%. It is worth noting that the nonlinear properties corresponding to the injected polarization state in our experiment are quite different from some earlier works.
Roles of tensor and isoscalar pairing interactions in β-decay calculations for possible r-process waiting point nuclei with N ~ 82 and 126*
Authors: Bai C. L. , Fang D. L. , Zhang H. Q. 
Published: July 2022

Abstract
In this study, we adopt the self-consistent Hartree-Fock-Bogoliubov (HFB) theory with the proton-neutron quasi-particle random phase approximation (pnQRPA) based on the Skyrme force for calculation of the β
− decay half-lives for nuclei with N ~ 82 and 126 on possible r-process paths. In the calculations, the Skyrme interaction (e.g., SKO') is adopted, and the tensor interaction is added self-consistently in both HFB and QRPA calculations. We systematically study how the half-life is changed by varying the strength of the triplet-even (TE) and triplet-odd (TO) components as well as the IS pairing. We find that a variation in strength of the IS pairing of approximately 20% does not produce a substantial effect on β-decay rates with or without the tensor force, while a strength variation of the TO tensor force considerably affects the change in the β-decay half-lives for the very neutron rich N ~ 82 and 126 isotonic chains. In addition, with the inclusion of the tensor force, the GT decay becomes dominant for very neutron-rich nuclei.
A-09 Challenges in Measuring Repetitive Head Impacts, Cognition, and Eye Movements in High School Football Players
Authors: Christianson K , Owusu V , Taylor M , Hopfe D , Pavilionis P , Murray N G 
Published: July 2022

Abstract
Purpose: Assess the feasibility of measuring Repetitive Head Impacts (RHI), cognition, and eye movements across a single season of high school football. Methods: Twelve players were provided an instrumented mouthguard (3200 Hz; Prevent Biometrics, Edina, MA) to evaluate RHI. Mouthguard use was assessed by total impacts and number of games/practices. Seven players also agreed to complete cognitive (ImPACT) and custom eye-tracking (500 Hz; EyeLink II) assessments pre-, mid-, and post-season. Multiple repeated measure ANOVA’s were completed using standard composite scores for ImPACT and oculomotor metrics. Results: Fifty percent of players ever used their mouthguard, and substantial variability in total impacts (M = 86.5, SD = 98.0, Range = 7–277) and number of games/practices (M = 9.8, SD = 7.6, Range = 2–23) were observed among players who did use their mouthguard. Specific completion rates for the 3 cognitive and 3 eye-tracking assessments were 71% each, and 57% of players completed all 6 scheduled assessments. Repeated measures ANOVA indicated Visual Motor Speed (VMS) improved between assessments (p = 0.015). Post hoc analysis showed both VMS and Verbal Memory increased from pre- to mid-season (−5.30(95%CI, −10.47 to −0.12), p = 0.046), (−0.20(95%CI, −13.00 to −1.41), p = 0.024). Conclusions: Variability in mouthguard use and missing assessment rates represent practical challenges in prospectively measuring RHI and utilizing multiple longitudinal assessment methods in high school football players. Although ImPACT results should be interpreted cautiously, future research should consider the potential role of practice effects and/or intentionally poor pre-season effort to explain the increase in performance during the season. A larger sample size will increase the possibility of measuring the effect of RHI on assessment outcomes.
A-10 Influence of Different Normative Reference Standards among Cognitively Normal Former NFL Players
Authors: Conley M , Schaffert J , Cullum C M , Hart J , Didehbani N 
Published: July 2022

Abstract
Purpose: Demographic adjustments (e.g., age, sex, race/ethnicity) to neuropsychological tests can assist clinical interpretation and avoid false-positive diagnoses of cognitive impairment. The issue of “race” as a criterion for normative adjustment has been highlighted in recent cases among former NFL players. We examined the impact of different normative reference comparisons on neuropsychological scores among cognitively normal Black and White NFL retirees. Methods: Cognitively normal Black (n = 20) and White (n = 20) retirees were age- and education-matched. Measures of attention (Digit Span), processing speed (Coding, TMTA), memory (ROCFT, CVLT), language (FAS, Animals, BNT), and executive function (TMTB) were examined. Independent samples t-tests (using p &lt; 0.01) were conducted between raw and normative scores of Black and White retirees that adjusted for 1) age/education (Mitrushina); 2) age/education/sex (NACC); and 3) age/education/sex/race (Heaton, MOANS/MOAANS). An additional ANCOVA evaluated group differences controlling for baseline estimated IQ. Results: Raw scores differed between groups on TMTB, Coding, and BNT. Mitrushina normative data showed differences on TMTB (p = 0.007) and BNT (p &lt; 0.001). NACC normative data showed differences on the BNT (p &lt; 0.001). ANCOVA (controlling for IQ) of raw scores between groups differed on the BNT (p = 0.002). Heaton and MOANS/MOAANS normative scores did not reveal differences between groups on any test. Conclusions: As expected, the use of different neuropsychological norms influences findings across different sociodemographic groups to various degrees, depending on the test. The underlying contributors to group differences using “race” as a proxy need to be disentangled and understood. Cautious use of demographically-adjusted norms as interpretive guidelines is warranted until these factors are identified.