bluuebunny/crossref_metadata_2025 huggingface dataset:
Exchange bias in heterostructures combining magnetic topological insulator MnBi2Te4 and metallic ferromagnet Fe3GeTe2
Authors: Qi Wuyi , Fei Fucong , Zhang Zhixin , Chen Bo , Xie Hangkai , Wei Boyuan , Zhang Shuai , Song Fengqi
Published: July 2024

Introducing magnetism into topological insulators enables exotic phenomena such as quantum anomalous Hall effect. By fabricating van der Waals (vdW) heterostructures using layered magnetic materials, we can not only induce a gap in the non-magnetic topological surface states through magnetic proximity but also further manipulate the magnetic properties of magnetic topological insulators. However, the scarcity of 2D ferromagnetic insulator materials limits the fabrication of such heterostructures. Here, we demonstrate the vdW heterostructure devices comprising metal ferromagnetic Fe3GeTe2 nanoflakes and few-layer antiferromagnetic topological insulator MnBi2Te4 separated by an insulating hexagonal-boron nitride spacer. These devices exhibit significant exchange bias with the exchange bias field of over 100 mT under certain conditions. Our results prove that besides magnetic insulators, metallic magnets can also effectively adjust the magnetic properties of topological insulators, thereby inspiring diverse configurations of the heterostructures between topological insulators and magnetic materials.
Effect of high pressure synthesis conditions on the formation of high entropy oxides
Authors: Aamlid Solveig Stubmo , Kim Minu , González-Rivas Mario U. , Oudah Mohamed , Takagi Hidenori , Hallas Alannah M.
Published: July 2024

High entropy materials are often entropy stabilized, meaning that the configurational entropy from multiple elements sharing a single lattice site stabilizes the structure. In this work, we study how high-pressure synthesis conditions can stabilize or destabilize a high entropy oxide (HEO). We study the high-pressure and high-temperature phase equilibria of two well-known families of HEOs: the rock salt structured compound (Mg,Co,Ni,Cu,Zn)O, including some cation substitutions, and the spinel structured compound (Cr,Mn,Fe,Co,Ni)3O4. Syntheses were performed at various temperatures, pressures, and oxygen activity levels, resulting in dramatically different synthesis outcomes. In particular, in the rock salt HEO, we observe the competing tenorite and wurtzite phases and the possible formation of a layered rock salt phase while the spinel HEO is highly susceptible to partial decomposition into a mixture of rock salt and corundum phases. At the highest tested pressures, 15 GPa, we discover the transformation of the spinel HEO into a metastable modified ludwigite-type structure with the nominal formula (Cr,Mn,Fe,Co,Ni)4O5. The relationship between the synthesis conditions and the final reaction product is not straightforward. Nonetheless, we conclude that high-pressure conditions provide an important opportunity to synthesize high entropy phases that cannot be formed any other way.
A coupled modeling framework for investigating flow maldistribution in cross-flow-corrugated plate heat exchangers
Authors: Li Haowen , Guo Xiaomei , Belotserkovsky Marat A. , Grigorchik Aleksandr N. , Kukareko Vladimir A. , Bo Zheng
Published: July 2024

Accurate prediction of the impact of flow maldistribution on the thermo-hydraulic behavior of plate heat exchangers is important for thermal design and optimization in a number of practical applications. In this paper, a coupled modeling framework, consisting of a heat transfer model and a hydraulic model, is proposed for quantitatively evaluating the impact of maldistribution on the thermo-hydraulic performance of a cross-flow-corrugated plate heat exchanger. The numerical results of the proposed approach are validated by comparison with experimental data. Using the coupled model, the flow distribution nonuniformity, heat exchanger effectiveness deteriorations, and pressure drop deviations are analyzed. Furthermore, the combined effects of side stream maldistribution are investigated for different inlet Reynolds numbers and inlet temperatures. The results demonstrate that when the inlet gas Reynolds number is in the range of 1100–2700, nonuniform distribution of the gas side will cause air maldistribution, and a 10%–30% effectiveness deterioration rate. It is found that air maldistribution will not result in gas maldistribution when the inlet air Reynolds number is in the range of 6000–18 000, but increasing air nonuniformity. Will lead to increasing deterioration in heat exchanger effectiveness. In the presence of air and gas flow maldistribution, the pressure drops on the gas and air sides increase by 5% and less than 12.4%, respectively. This work provides a computational framework for optimization of cross-flow-corrugated plate heat exchangers to achieve desired thermo-hydraulic performance.
Tightly confined tellurium nanocrystals in few-layer expanded graphite with Te–C bonds toward highly reversible zinc storage
Authors: Yang Hengyu , Liang Yongle , Niu Fengjun , Zhang Huaijun , Xu Guobao , Wei Xiaolin , Yang Liwen
Published: July 2024

Tellurium (Te) has great potential as high-performance cathode materials for aqueous zinc-ion batteries (AZIBs) owing to high electronic conductivity and volumetric capacity. Nevertheless, its poor utilization and large volume expansion result in insufficient rate and cycle performances, thereby, impeding practical application. Herein, a kind of Te/carbon composite was prepared via a ball-milling method, in which Te nanocrystals were tightly confined in few-layer expanded graphite (EG) with Te–C bonds (denoted as Te@EG). In addition to maintaining structural stability, such unique nanocomposite shows abundant electrochemically active sites and efficient charge transfer channels, which is beneficial to the utilization of Te. More importantly, the Te–C bonds between Te nanocrystals and EG can enhance the adsorption of Zn2+ and reduce the Zn2+ migration barrier, which contributes to promoting electrochemical kinetics. Consequently, the Te@EG cathode for the AZIBs exhibits sufficient specific capacity (412 mAh g–1 at 0.1 A g–1), high-rate performance (284 mAh g–1 at 3 A g–1), and reliable cycling stability (94% capacity retention at 1 A g–1 after 500 cycles). Furthermore, the soft-packaged Zn//Te@EG battery delivers excellent flexibility and cycling stability. This study offers a perspective on rational design of Te-based cathodes for practical AZIBs.
Influence of inhomogeneous distribution of inflow equivalence ratio on oblique detonation morphology and characteristic
Authors: Sun Yue , Wang Shuo , Zhao Majie , Guo Hongbo
Published: July 2024

In this paper, numerical simulations using Euler equations coupled detailed chemical reaction model are performed to reveal the influence of inhomogeneous distribution of inflow equivalence ratio (ER) on the morphology and characteristic of oblique detonation in hydrogen/oxygen/argon mixtures. The purpose of this study is to better understand the key parameters’ variation law of oblique detonation flow field under practical flight conditions so as to guide the design of oblique detonation chamber. Within the scope of our simulations, the results show that the oblique detonation wave (ODW) can still be standing under a large ER gradient. The thermodynamic state and characteristic sizes of the flow field reach the maximum value around ER = 0.8. First, the ODW angle and the post-wave temperature/pressure increase with the homogeneous inflow ER. Then, the inhomogeneity of inflow ER is introduced by assuming a lateral linear distribution covering the whole inflow boundary. When the ER increases along the inflow boundary with ER = 0 at the wedge tip, the overall morphology of the ODW presents a concave structure. Inversely, the ODW is convex with ER = 0 at the top outlet. The morphology and characteristic sizes of ODW are determined by the mixture composition in front of the corresponding wave surface. The transition mode of ODW is mainly determined by the ER of the incoming flow in front of the induction region.
Enhancing overall performance of thermophotovoltaics via deep reinforcement learning-based optimization
Authors: Yu Shilv , Chen Zihe , Liao Wentao , Yuan Cheng , Shang Bofeng , Hu Run
Published: July 2024

Thermophotovoltaic (TPV) systems can be used to harvest thermal energy for thermoelectric conversion with much improved efficiency and power density compared with traditional photovoltaic systems. As the key component, selective emitters (SEs) can re-emit tailored thermal radiation for better matching with the absorption band of TPV cells. However, current designs of the SEs heavily rely on empirical design templates, particularly the metal-insulator-metal (MIM) structure, and lack of considering the overall performance of TPV systems and optimization efficiency. Here, we utilized a deep reinforcement learning (DRL) method to perform a comprehensive design of a 2D square-pattern metamaterial SE, with simultaneous optimization of material selections and structural parameters. In the DRL method, only the database of refractory materials with gradient refraction indexes needs to be prepared in advance, and the whole design roadmap will automatically output the SE with optimal Figure-of-Merit (FoM) efficiently. The optimal SE is composed of a novel material combination of TiO2, Si, and W substrate, with its thickness and structure precisely optimized. Its emissivity spectra match well with the external quantum efficiency curve of the GaSb cell. Consequently, the overall performance of TPV is significantly enhanced with an output power density of 5.78 W/cm2, an energy conversion efficiency of 38.26%, and a corresponding FoM of 2.21, surpassing most existing designs. The underlying physics of optimal SE is explained by the coupling effect of multiple resonance modes. This work advances the practical application potential of TPV systems and paves the way for addressing other multi-physics optimization problems and metamaterial designs.
Unraveling relationship between complex lifetimes and microscopic diffusion in deep eutectic solvents
Authors: Rinesh T. , Srinivasan H. , Sharma V. K. , Mitra S.
Published: July 2024

Aqueous mixtures of deep eutectic solvents (DESs) have emerged as a subject of interest in recent years for their tailored physicochemical properties. However, a comprehensive understanding of water’s multifaceted influence on the microscopic dynamics, including its impact on improved transport properties of the DES, remains elusive. Additionally, the diffusion mechanisms within DESs manifest heterogeneous behavior, intricately tied to the formation and dissociation kinetics of complexes and hydrogen bonds. Therefore, it is imperative to explore the intricate interplay between bond kinetics, diffusion mechanism, and dynamical heterogeneity. This work employs water as an agent to explore their relationships by studying various relaxation phenomena in a DES based on acetamide and lithium perchlorate over a wide range of water concentrations. Notably, acetamide exhibits Fickian yet non-Gaussian diffusion across all water concentrations with Fickian (τf) and Gaussian (τg) timescales following a power-law relationship, τg∝τfγ, γ ∼ 1.4. The strength of coupling between bond kinetics and different diffusion timescales is estimated through various power-law relationships. Notably, acetamide–water hydrogen bond lifetime is linked to diffusive timescales through a single power-law over the entire water concentration studied. However, the relationship between diffusive timescales and the lifetime of acetamide–lithium complexes shows a sharp transition in behavior at 20 wt. % water, reflecting a change from vehicular diffusion below this concentration to structural diffusion above it. Our findings emphasize the critical importance of understanding bond dynamics within DESs, as they closely correlate with and regulate the molecular diffusion processes within these systems.
Boosting the efficiency of InGaN-based green LEDs grown on Si through buffer strain engineering
Authors: Dai Yayu , Liu Jianxun , Sun Xiujian , Zhan Xiaoning , Luo Yujiao , Zhang Shuming , Sun Qian , Wang Liangji , Ji Yun , Ikeda Masao , Yang Hui
Published: July 2024

InGaN-based micro-light-emitting diodes (LEDs) grown on Si have gained tremendous interest for full-color displays. Strain management is a key challenge for the epitaxial growth of InGaN-based long-wavelength LEDs on Si because the accumulated compressive strain can severely limit In incorporation and degrade the quality of InGaN multi-quantum wells (MQWs) when the conventional Al-composition step-graded AlN/AlGaN buffer is used for strain control. In this work, we demonstrate a promising approach to effectively reduce the in-plane residual compressive stress of GaN by using an AlN single-layer buffer. The in-plane lattice parameter of the GaN underlayer was increased from 3.183 to 3.189 Å with the residual compressive stress at room temperature reduced from 0.37 to ∼0 GPa, which significantly improved the In incorporation of InGaN MQWs and extended the photoluminescence wavelength from 510 to 550 nm. A remarkably high internal quantum efficiency of 78% was thus achieved for the as-grown InGaN-based green LEDs on Si. This work paves the way for the growth of high-efficiency InGaN-based long-wavelength micro-LEDs.
The Black Lives Matter movement mitigates bias against racial minority actors
Authors: Lin Yu-Wei , Yang Shiyu , Han Wencui , Lu Jackson G.
Published: July 2024

Watching movies is among the most popular entertainment and cultural activities. How do viewers react when a movie sequel increases racial minority actors in the main cast (“minority increase”)? On the one hand, such sequels may receive better evaluations if viewers appreciate racially inclusive casting for its novel elements (the value-in-diversity perspective) and moral appeal (the fairness perspective on diversity). On the other hand, discrimination research suggests that if viewers harbor biases against racial minorities, sequels with minority increase may receive worse evaluations. To examine these competing possibilities, we analyze a unique panel dataset of movie series released from 1998 to 2021 and conduct text analysis of 312,457 reviews of these movies. Consistent with discrimination research, we find that movies with minority increase receive lower ratings and more toxic reviews. Importantly, these effects weaken after the advent of the Black Lives Matter (BLM) movement, especially when the movement’s intensity is high. These results are reliable across various robustness checks (e.g., propensity score matching, random implementation test). We conceptually replicate the bias mitigation effect of BLM in a preregistered experiment: Heightening the salience of BLM increases White individuals’ acceptance of racial minority increase in a movie sequel. This research demonstrates the power of social movements in fostering diversity, equality, and inclusion.
The gender agency gap in fiction writing (1850 to 2010)
Authors: Stuhler Oscar
Published: July 2024

Works of fiction play a crucial role in the production of cultural stereotypes. Concerning gender, a widely held presumption is that many such works ascribe agency to men and passivity to women. However, large-scale diachronic analyses of this notion have been lacking. This paper provides an assessment of agency attributions in 87,531 fiction works written between 1850 and 2010. It introduces a syntax-based approach for extracting networks of character interactions. Agency is then formalized as a dyadic property: Does a character primarily serve as an agent acting upon the other character or as recipient acted upon by the other character? Findings indicate that female characters are more likely to be passive in cross-gender relationships than their male counterparts. This difference, the gender agency gap, has declined since the 19th century but persists into the 21st. Male authors are especially likely to attribute less agency to female characters. Moreover, certain kinds of actions, especially physical and villainous ones, have more pronounced gender disparities.
Sediment subduction in Hadean revealed by machine learning
Authors: Jiang Jilian , Zou Xinyu , Mitchell Ross N. , Zhang Yigang , Zhao Yong , Yin Qing-Zhu , Yang Wei , Zhou Xiqiang , Wang Hao , Spencer Christopher J. , Shan Xiaocai , Wu Shitou , Li Guangming , Qin Kezhang , Li Xian-Hua
Published: July 2024

Due to the scarcity of rock samples, the Hadean Era predating 4 billion years ago (Ga) poses challenges in understanding geological processes like subaerial weathering and plate tectonics that are critical for the evolution of life. The Jack Hills zircon from Western Australia, the primary Hadean samples available, offer valuable insights into magma sources and tectonic genesis through trace element signatures. However, a consensus on these signatures has not been reached. To address this, we developed a machine learning classifier capable of deciphering the geochemical fingerprints of zircon. This allowed us to identify the oldest detrital zircon originating from sedimentary-derived “S-type” granites. Our results indicate the presence of S-type granites as early as 4.24 Ga, persisting throughout the Hadean into the Archean. Examining global detrital zircon across Earth’s history reveals consistent supercontinent-like cycles from the present back to the Hadean. These findings suggest that a significant amount of Hadean continental crust was exposed, weathered into sediments, and incorporated into the magma sources of Jack Hills zircon. Only the early operation of both subaerial weathering and plate subduction can account for the prevalence of S-type granites we observe. Additionally, the periodic evolution of S-type granite proportions implies that subduction-driven tectonic cycles were active during the Hadean, at least around 4.2 Ga. The evidence thus points toward an early Earth resembling the modern Earth in terms of active tectonics and habitable surface conditions. This suggests the potential for life to originate in environments like warm ponds rather than extreme hydrothermal settings.
Space, body and presence
Authors: Jerkovic Tiana
Published: July 2024

The trend towards remote interpreting has caused a radical change for interpreters worldwide, one that has shifted
their workplace from well-known physical spaces to new digital spaces. Research to date has documented specific settings, language
combinations and/or interpreting modes, and it has usually focused on certain forms of remote interpreting (e.g., video remote
interpreting, video relay service). The combinations of different characteristics and factors in remote interpreting are almost
infinite, however, and single terms fail to depict and cover all possible variations. This article proposes an analytical
framework that uses conceptualisations of space, body and presence to analyse interpreting assignments in digital spaces,
regardless of language combination, setting and mode. Two examples are used to illustrate the application of this framework: a
hybrid conference and a meeting in virtual reality (VR), both of them involving sign language interpreting. The use of VR has
undergone a substantial increase in the past few years, having developed rapidly. It is therefore possible that future
interpreting assignments might take place in this new digital space. The application of these two scenarios shows that the
analytical framework can be used both to reflect on past and to anticipate future assignments.
Spatial analysis of multi-frequency SAW beams excited by slanted IDTs on ZnO-SiC heterostructures
Authors: Liou Y-T , Msall M , Hernández-Mínguez A , Santos P V
Published: July 2024

Slanted (or fan-shaped) interdigital transducers (IDTs) with broadband response allow the selective excitation of surface acoustic waves (SAWs) with narrow beam widths and pathways controlled by the excitation frequency. Such SAW-based spatial and frequency control is important for applications in microfluidics, as well as in emerging applications in semiconductor nanostructures. In this contribution, we generate both Rayleigh and Sezawa modes with slanted IDTs on a 4H-SiC substrate coated with a piezoelectric ZnO film. We directly measure the phase wavefronts of narrow SAW beams in the 1200–1260 MHz frequency bandwidth using high-resolution (

<

1
μ

m

) optical interferometry, and discuss the mechanisms that directly affect the propagation direction and phase profiles of the SAW beams. The combination of multimodal and multi-frequency SAW delay lines provides rich opportunities for SAW-based control of low-dimensional systems, such as electrons in epitaxial graphene or spin centers near the surface of the SiC substrates.
Medium dynamic field range linear bipolar spin valve sensor through soft pinning the sensing layer
Authors: Gawade Tejaswini C , Borole Umesh P , Behera Bhagaban , Ghosh S K , Bysakh S , Biswas A , Khan Jakeer , Chowdhury P
Published: July 2024

Magnetic sensor with spin valve-GMR technology with medium dynamic range is designed for a diversity of applications, including linear and rotary position measurements, proximity switches, and current sensors. For this, the sensing layer (SL) of the spin valve stack was modified by a soft pinning layer (SPL) through an exchange bias field created by an antiferromagnetic layer which has a lower blocking temperature than the one that is kept adjacent to the pinned layer. Numerical simulation was carried out to control the bias field by keeping a non-magnetic Ru spacer layer between the SPL and SL layers and the results were experimentally verified. The magnetic sensor was fabricated with linear operating field range of the order ±100 Oe having a sensitivity of the order of 0.1 m V V−1 Oe−1 near zero field. The thermal performance confirms that the device can be operated in the temperature range of −40 ∘C to 125 ∘C and it has a thermal coefficient of voltage around 15 µV V−1∘C−1.
A coarse and fine-grained deep multi view subspace clustering method for unsupervised fault diagnosis of rolling bearings
Authors: Huang Wenjun , Mi Junpeng , Zhao Huanpeng , Wang Yifei , Xue Shenghao , Jin Jianxiang
Published: July 2024

To address the issue of insufficient characterization of fault features in inherent vibration data that affects the performance of unsupervised learning-based fault diagnosis, a coarse and fine-grained deep multi view subspace clustering method (CFG-DMVSC) for unsupervised fault diagnosis of rolling bearings is proposed. The proposed method designs a convolutional autoencoder network based on the Gramian angular field transformation for multi-signal analysis domains. A multi-view coarse-grained self-expressive method based on information entropy is designed to handle differences in information across different views. Furthermore, a fine-grained common and independent information separation loss function based on mutual information is proposed to ensure compactness among multiple views. Both the Case Western Reserve University rolling bearing dataset and privately built bearing fault test bench data demonstrate that, compared to existing methods, the proposed method can perform coarse and fine-grained division in multi-view subspaces, achieving better clustering diagnosis performance on the extracted common information among views.
Experimental study on strengthening the magneto-mechanical coupling effect of X80 steel by weak magnetic excitation
Authors: He Tengjiao , Liao Jiancheng , Liao Kexi , Zhu Hongdong , Tang Jing , Jiang Pan , Xia Guoqiang
Published: July 2024

Current magnetic stress detection techniques are significantly affected by external noise. Magnetic stress detection technology under magnetic field excitation is proposed to weaken the external noise signals on the detection results. In this study, the uniaxial tensile magnetic signal testing system with the excitation magnetic field was developed. The enhancement of the weak magnetic excitation in magnetic signals has been analyzed and the concept of optimal weak excitation magnetic field has been proposed. The response law between triaxial magnetic induction intensity and stress under the excitation magnetic field is determined. The results indicate that the weak excitation magnetic field significantly enhances the magnetic induction signal intensity, more importantly, the linearity of the magnetic signal and stress response is also enhanced. Furthermore, the optimal excitation magnetic field under uniaxial stress states is 600 A m−1, and the corresponding stress-magnetic change rate is 0.002 Oe MPa−1. This study provides a theoretical basis for the long-distance detection of pipelines under weak magnetic excitation. The long-distance magnetic stress detection results of pipelines will become more accurate with the weak magnetic excitation which has a good engineering significance.
Wafer scale WS2 based ultrafast photosensing and memory computing devices for neuromorphic computing
Authors: B Sharmila , Dwivedi Priyanka
Published: July 2024

Integration of optical sensors with memristors can establish the bridge between photosensing and memory devices for Internet of Things (IoT) based applications. This paper presents the realization of integrated sensing and computing memory (ISCM) devices using tungsten disulfide (WS2) and their application for neuromorphic computing. The ISCM device fabrication process is scalable as microfabrication steps followed on 2″ wafer, ISCM device testing and image classification for neuromorphic computing. The photosensing/memory tests were conducted using electrical and optical stimulations (broadband spectrum). The fabricated photosensing device offers a higher responsivity (8 A W−1), higher detectivity (2.85 × 1011 Jones) and fast response speed (80.2/78.3 μs) at 950 nm. The memory device has shown a set/reset time of 51.6/73.5 μs respectively. Further, the repeatability, stability and reproducibility tests were conducted by stimulating the device with different modulating frequencies. The frequency modulation tests confirm that the ISCM devices are stable and perfect candidate for real-time IoT applications. Moreover, the device’s potentiation and depression results were used for image classification with the accuracy of 98.27%. These demonstrated device’s test results provide possibilities to fabricate the smart sensors with integrated functionalities.
Non-uniform critical current and stacking effect remedy for multi-filament REBCO tapes with potential defects
Authors: Cai Tiantian , Wang Mingyang , Hao Luning , Meng Xuan’ang , Chen Haolan , Jiang Junjie , Sheng Jie , Jin Zhijian
Published: July 2024

The high aspect ratio of REBCO tapes has a significant impact on several characteristics in high-temperature superconducting applications, such as critical current and AC loss. Narrow filamentary technology can effectively reduce the impact of magnetic field dependence and enhance the electromagnetic performance of REBCO tapes. However, the existing methods are constrained by the trade-off between the narrow degree of REBCO filaments and high current capacity. Meanwhile, when processing REBCO tapes for large-scale magnets, there is a great possibility that local defects are lurking. A striated narrow-stacked (NS) structure is proposed based on the existing narrowing methods to address these challenges. To verify the validity of this structure, it is imperative to explore the non-uniform critical current and stacking effect on performance for multi-filament REBCO tapes with potential defects. This article introduces a magnetic extended network (MEN) model to analyze the electrical characteristics of striated NS structures with different types of potential defects. Then, by coupling with a 3D finite element method electromagnetic module, the calculation results of the MEN model are visualized and used to analyze the electromagnetic characteristics including current sharing mechanism, magnetic field distribution, and critical current compensation due to stacking effect. It is found that stack structures successfully provide the performance remedy for multi-filament REBCO tapes with potential defects. This study aims to promote the narrowing improvement of REBCO tapes in high-field magnets and high-current applications.
Atomic and electronic structures of Ni64Zr36 metallic glass under high pressure
Authors: Kostera Zuzanna , Antonowicz Jerzy , Dzięgielewski Przemysław
Published: July 2024

Amorphous metallic alloys, also known as metallic glasses (MGs), are materials with unique physical properties resulting from their disordered yet densely packed atomic structure. The packing density of MGs can be further enhanced by external pressure, forcing the decrease of interatomic distances and modifying both the atomic and electronic structure of an alloy. This work reports on classical molecular dynamics (MD) and density functional theory (DFT) studies of Ni64Zr36 MG in a hydrostatic pressure range of 0–120 GPa. The MD simulations revealed that compression leads to enhanced short-range ordering by increasing the contribution of efficiently packed icosahedral-like clusters. According to the DFT calculations, for pressure above 50 GPa, Zr atoms show a significant change in electronic configuration, with a dominant charge transfer from their s and p to d-states and charge redistribution between Ni and Zr atoms. This variation is correlated with the appearance of pairs with significantly shortened interatomic distances, as detected by the MD. We conclude that the enhanced icosahedral ordering in Ni64Zr36 MG is induced not only by the pressure-driven densification of an alloy but also by a variation of its electronic structure.
The cosmic-ray positron excess and its imprint in the Galactic gamma-ray sky
Authors: Rocamora M. , Ascasibar Y. , Sánchez-Conde M.A. , Wechakama M. , de la Torre Luque P.
Published: July 2024

We study the origin of the positron excess observed in the local cosmic-ray spectrum at
high energies, and relate it to the cosmic rays and gamma-ray emission across the entire Galaxy.
In particular, we explore the hypothesis of a single, dominant source accountable for primary
electron-positron pairs. Since we are agnostic about the physical nature of the underlying source
population, we consider four models that are representative of young pulsars, old stars (as a
tracer of millisecond pulsars), and annihilating dark matter particles. In the dark matter
hypothesis, we consider both a cored and a cuspy model for the halo in the Milky Way. Then, we
compare the associated gamma-ray sky maps with Fermi-LAT data. We find that the emission
arising from pulsar wind nebulae is fairly concentrated near the mid plane, and therefore
additional cosmic-ray sources must be invoked to explain the emission at the center of the
Galaxy. If the local positron excess were mainly due to millisecond pulsars, inverse Compton
scattering by the particles injected would naturally account for a non-negligible fraction of the
central gamma-ray emission. The same process would lead to a tension for a standard NFW dark
matter profile, exceeding the gamma-ray data by almost a factor of 2 in some regions of the
Galaxy. Although the results for an isothermal, cored profile are in agreement with these data,
the cross section needed in both cases is around 2 orders of magnitude above the thermal
cross-section, disfavouring the dark matter interpretation.
Discrete orbit effect lengthens merger times for inspiraling binary black holes
Authors: Page Don N.
Published: July 2024

The inspiral merger time for two black holes captured into a nonrelativistic bound orbit by gravitational radiation emission has been often calculated by a formula of Peters that assumes the adiabatic approximation that the changes per orbit are small. However, initially this is not true for the semimajor axis and period of most of the initially highly eccentric orbits, which change significantly during closest approach and much less elsewhere along the orbit. This effect can make the merger time much longer (using other formulas from Peters that do not assume the adiabatic approximation) than that calculated by the adiabatic formula of Peters.
Leptogenesis effects on the gravitational waves background:
interpreting the NANOGrav measurements and JWST constraints on primordial
black holes
Authors: El Bourakadi K. , Chakir H. , Khlopov M.Yu.
Published: July 2024

We demonstrate that the leptogenesis mechanisms, which are associated with B-L symmetry
breaking mechanism has notable effects on the production of gravitational waves. These
gravitational waves align well with the recent observations of a stochastic gravitational wave
background by NANOGrav and pulsar-timing arrays (PTAs). For these gravitational waves to match the
recent measurements, the critical value of the B-L breaking should be around the GUT
scale. Moreover, we consider the generation of primordial gravitational waves from binary systems
of Primordial Black Holes (PBHs) which could be predicted by the recent detection of
gravitational waves. PBHs with specific masses can be responsible for massive galaxy formation
observed at high redshifts reported by the James Webb Space Telescope (JWST). We contemplate the
potential for a shared source between the NANOGrav and JWST observations, namely primordial black
holes. These black holes could serve as seeds of rapid galaxy formation, offering an explanation
for the galaxies observed by JWST.
Isotope effects and Alfvén eigenmode stability in JET H, D, T, DT, and He plasmas
Authors: Tinguely R.A. , Puglia P.G. , Dowson S. , Porkolab M. , Douai D. , Fasoli A. , Frassinetti L. , King D. , Schneider P. ,   JET Contributors
Published: July 2024

While much about Alfvén eigenmode (AE) stability has been explored in previous and current tokamaks, open questions remain for future burning plasma experiments, especially regarding exact stability threshold conditions and related isotope effects; the latter, of course, requiring good knowledge of the plasma ion composition. In the JET tokamak, eight in-vessel antennas actively excite stable AEs, from which their frequencies, toroidal mode numbers, and net damping rates are assessed. The effective ion mass can also be inferred using measurements of the plasma density and magnetic geometry. Thousands of AE stability measurements have been collected by the Alfvén Eigenmode Active Diagnostic in hundreds of JET plasmas during the recent Hydrogen, Deuterium, Tritium, DT, and Helium-4 campaigns. In this novel AE stability database, spanning all four main ion species, damping is observed to decrease with increasing Hydrogenic mass, but increase for Helium, a trend consistent with radiative damping as the dominant damping mechanism. These data are important for confident predictions of AE stability in both non-nuclear (H/He) and nuclear (D/T) operations in future devices. In particular, if radiative damping plays a significant role in overall stability, some AEs could be more easily destabilized in D/T plasmas than their H/He reference pulses, even before considering fast ion and alpha particle drive. Active MHD spectroscopy is also employed on select HD, HT, and DT plasmas to infer the effective ion mass, thereby closing the loop on isotope analysis and demonstrating a complementary method to typical diagnosis of the isotope ratio.
Plasma performance and operational space with an RMP-ELM suppressed edge
Authors: Paz-Soldan C. , Gu S. , Leuthold N. , Lunia P. , Xie P. , Kim M.W. , Kim S.K. , Logan N.C. , Park J.-K. , Suttrop W. , Sun Y. , Weisberg D.B. , Willensdorfer M. ,   the ASDEX Upgrade Team,   the DIII-D Team,   the EAST Team,   the KSTAR Team
Published: July 2024

The operational space and global performance of plasmas with edge-localized modes (ELMs) suppressed by resonant magnetic perturbations (RMPs) are surveyed by comparing AUG, DIII-D, EAST, and KSTAR stationary operating points. RMP-ELM suppression is achieved over a range of plasma currents, toroidal fields, and RMP toroidal mode numbers. Consistent operational windows in edge safety factor are found across devices, while windows in plasma shaping parameters are distinct. Accessed pedestal parameters reveal a quantitatively similar pedestal-top density limit for RMP-ELM suppression in all devices of just over

3
×

10

19

 m−3. This is surprising given the wide variance of many engineering parameters and edge collisionalities, and poses a challenge to extrapolation of the regime. Wide ranges in input power, confinement time, and stored energy are observed, with the achieved triple product found to scale like the product of current, field, and radius. Observed energy confinement scaling with engineering parameters for RMP-ELM suppressed plasmas are presented and compared with expectations from established H and L-mode scalings, including treatment of uncertainty analysis. Different scaling exponents for individual engineering parameters are found as compared to the established scalings. However, extrapolation to next-step tokamaks ITER and SPARC find overall consistency within uncertainties with the established scalings, finding no obvious performance penalty when extrapolating from the assembled multi-device RMP-ELM suppressed database. Overall this work identifies common physics for RMP-ELM suppression and highlights the need to pursue this no-ELM regime at higher magnetic field and different plasma physical size.
Radon removal commissioning of the PandaX-4T cryogenic distillation system
Authors: Cui Xiangyi , Wang Zhou , Li Jiafu , Li Shuaijie , Si Lin , Ju Yonglin , Ma Wenbo , Liu Jianglai , Zhao Li , Ji Xiangdong , Yan Rui , Sha Haidong , Huang Peiyao , Wang Xiuli , Liu Huaxuan
Published: July 2024

The PandaX-4T distillation system, designed for the removal of krypton and radon from xenon, is evaluated for its radon removal efficiency using a222Rn source during the online distillation process. The PandaX-4T dark matter detector is employed to monitor the temporal evolution of radon activity. To determine the radon reduction factor, the experimental data of radon atoms introduced into and bypassed the distillation system is compared. The results indicate that the PandaX-4T distillation system achieves a radon reduction factor exceeding 190 at the flow rate of 10 slpm and the reflux ratio of 1.44. Gas-only online distillation process of a flow rate of 20 slpm is also conducted without observing significant reduction of radon levels in the detector. This observation suggests that the migration flow of radon atoms from the liquid phase to the gas phase is limited, and the flow rate of gas circulation and duration of the process are insignificant compared to the total xenon mass of 5.6 tons in the detector. This study provides the experimental data to support the efficient removal of radon at  ∼Bq level using the PandaX-4T distillation system, which is the prerequisite of the radon background control in the detector. The further operation with higher flow rate will be applied for the upcoming science run in PandaX-4T.
Regulation of the global carbon and water cycles through vegetation structural and physiological dynamics
Authors: Li Wantong , Duveiller Gregory , Wieneke Sebastian , Forkel Matthias , Gentine Pierre , Reichstein Markus , Niu Shuli , Migliavacca Mirco , Orth Rene
Published: July 2024

Vegetation plays an essential role in regulating carbon and water cycles, e.g. by taking up atmospheric CO2 through photosynthesis and by transferring soil water to the atmosphere through transpiration. Vegetation function is shaped by its structure and physiology: vegetation structure is determined by the amount of materials for plants and how it is organised in space and time, while vegetation physiology controls the instantaneous response of vegetation function to environmental conditions. Recognizing and disentangling these aspects of vegetation is key to understanding and predicting the response of the terrestrial biosphere to global change. This is now possible, as comprehensive measurements from Earth observations, both from satellites and the ground, provide invaluable data and information. This review introduces and describes vegetation structure and physiology, and summarises, compares, and contextualises recent literature to illustrate the state of the art in monitoring vegetation dynamics, quantifying large-scale vegetation physiology, and investigating vegetation regulation on the changes of global carbon and water fluxes. This includes results from remote sensing, in-situ measurements, and model simulations, used either to study the response of vegetation structure and physiology to global change, or to study the feedback of vegetation to global carbon and water cycles. We find that observation-based work is underrepresented compared with model-based studies. We therefore advocate further work to make better use of remote sensing and in-situ measurements, as they promote the understanding of vegetation dynamics from a fundamental data-driven perspective. We highlight the usefulness of novel and increasing satellite remote sensing data to comprehensively investigate the structural and physiological dynamics of vegetation on the global scale, and to infer their influence on the land carbon sink and terrestrial evaporation. We argue that field campaigns can and should complement large-scale analyses together with fine spatio-temporal resolution satellite remote sensing to infer relevant ecosystem-scale processes.
The quality of pliek-u processed by using adaptive technologies
Authors: Khathir R , Yunita  , Hartuti S , Rahmawati M
Published: July 2024

This study aimed to evaluate the quality of pliek-u processed by using adaptive technologies namely a solar tunnel dryer type Hohenheim Aceh for drying pliek-u and a hydraulic press for separating the pliek oil from pliek-u. About 100 coconuts were grated and fermented for 9days, then dried by using a solar tunnel dryer type Hohenheim Aceh and pressed by the hydraulic press. Parameters observed were moisture, total acidity, acidity, fat content, ash content, and yield. An organoleptic test was also conduct on 30 consumers. Results showed that the moisture of pliek-u ranged from 8.61 to 12.29%. The total acidity and pH-value of pliek-u were 0.52% and 5.5, respectively. Pliek-u has fat content about 43.65% and ash content approximately 5.3%, while the yield of pliek-u was 31.33%. The consumer test showed that the average preferences score of pliek-u for all sensory properties were 4 (like). In conclusion, the quality of pliek-u processed by using adaptive technologies were good as it was processed conventionally. Moreover, some quality properties such as pH-value and fat content can be improved so that the shelf-life of pliek-u could be extended.
Nutritional content of complementary feeding instant kanji rumbi porridge with the addition of quail egg flour
Authors: Suryana S , Marliyati SA , Khomsan A , Dwiriani CM
Published: July 2024

Kanji Rumbi porridge is an Acehnese traditional local food. The limitations of this complementary food are incomplete nutritional and long processing, so it requires innovation in development. Kanji Rumbi potentialy to become an instant complementary food through drying processing. Objective: analyze the effect of instant Kanji Rumbi porridge with drum drying method on nutritional content. Completely Randomized Design (CRD) experiment with two replications. The research was carried out in August-September 2023, at the Food Processing and Experimentation Laboratory of the Department of Public Nutrition, IPB, instantiated at the IPB Seafast Laboratory and nutritional analysis at the Saraswanti Indo Genetech (SIG) Laboratory, Bogor. Data analysis used the Paired t-test (p<0.05). The instant Kanji Rumbi product has a yield value of 25%. There were significant differences in the nutritional content of fresh and instant Kanji Rumbi in terms of water content, energy, carbohydrates, fat, fiber, Vitamin A, sodium, zinc, iron. There was no significant difference in ash, protein, iodine and calcium levels. Most of the nutritional content of instant Kanji Rumbi is higher than fresh porridge.
Extraction of patchouli essential oil using multi-injection steam distillation
Authors: Arliani R , Machdar I , Kurnia N S , Bakar A , Husni
Published: July 2024

Patchouli essential oil is typically obtained through traditional batch distillation, a process involving the introduction of a sole stream of steam at the base of the tank or column, followed by the condensation of the resulting vapor at the top of the tank. In a quest to explore the impact of the multiple injection steam method on both the yield and quality of the oil product, a comparison with the conventional single injection steam approach was conducted. The research variables encompassed different steam valve openings. The findings revealed that the steam valve openings indeed played a role in affecting the yield of the oil product. Curiously, the utilization of the multiple injection steam method yielded a somewhat lower oil output compared to the single injection steam approach. Specifically, with varying steam valve openings, the average yield for the multiple injection steam method hovered around 2.6%. In contrast, the single injection steam method consistently demonstrated a superior average yield of about 3.9%. Intriguingly, an examination of the essential components of patchouli oil, particularly the patchouli alcohol content, indicated no marked disparity between the two methods. This suggests that the utilization of the multiple injection steam method did not substantially alter the essential oil’s composition.
Morphological relationship of coffee varieties (Coffea spp.) arabica and robusta in Pondok Gajah Experimental Garden Bener Meriah
Authors: Harnelly E , Heriansyah F , Iqbar  , Ramlan R R
Published: July 2024

Coffee is one of the plantation commodities with a high economic value among other plantation crops and plays an important role as a source of foreign exchange. Indonesian coffee is classified into two types of coffee, namely arabica coffee and robusta coffee. According to data from the Central Bureau of Statistics of Aceh Province (2019), the area of coffee plantations in Aceh reached 123,749 ha with a production of 68,493 tons. About 85% of the land area is planted with arabica coffee, while the rest is planted with robusta coffee. This study analyzes the morphological relationships of various Arabica and Robusta coffee plant varieties at the Gayo Experimental Garden, Pondok Gajah District, Bener Meriah Regency, Aceh Province. Samples of coffee varieties were selected by purposive sampling method. The morphological characters observed were 25 on stem organs, leaves, flowers, fruits, and beans. Data analysis was conducted using the NTSYS program and presented as a dendrogram. The results showed that eleven coffee varieties were grouped into four groups. The variety that has the furthest kinship is Mocca Yaman, with a coefficient value of 0.58. The varieties with the closest kinship are C 48 and C 49, with a coefficient value of 0.84. These two varieties have similarities in the 19 observed morphological characters.