bluuebunny/crossref_metadata_2025 huggingface dataset:
Strain in 2D TMDCs induced by metal-assisted exfoliation from the polyvinyl alcohol-covered substrate
Authors: Kamenskaya T. A. , Eliseyev I. A. , Davydov V. Yu. , Kuntsevich A. Yu.
Published: October 2024

We have modified the metal-assisted transfer technique to obtain large-area, few-layer flakes from transition metal dichalcogenide bulk crystals by introducing an initial stage—exfoliation of the bulk crystal onto an intermediate substrate, specifically a silicon wafer coated with polyvinyl alcohol. Following this, we thermally evaporate silver onto the sample and transfer the top layers of the crystal along with the silver layer to the target substrate. This technique allows the production of visually non-corrugated single- and few-layer flakes with high yield. A direct comparison of the micro-Raman and micro-photoluminescence spectra of flakes exfoliated using our method with the spectra of those exfoliated from the scotch tape reveals differences in their properties. We identify signatures of deformations in the flakes exfoliated from the intermediate substrate, indicating the presence of static friction between the substrate and the flake. Our findings, thus, suggest a useful method to induce intrinsic deformation in 2D materials.
Enhanced spin–orbit torque in Pt/Sm/Co/Ta heterostructures by interface alloying with light rare-earth Sm layer
Authors: Li Dong , Li Minrui , Lai Yanping , Zhang Wei , Liu Xiyue , Quan Zhiyong , Xu Xiaohong
Published: October 2024

Current-induced spin–orbit torque (SOT) has attracted much attention due to its potential applications in energy-efficient logic, memory, and artificial neuron devices. In this work, we report an enhanced SOT efficiency in perpendicularly magnetized Pt/Sm/Co/Ta heterostructures by inserting a light rare-earth Sm layer with large spin–orbit coupling. A series of Ta/Pt/Sm/Co/Ta samples with the Sm layer thickness (tSm) of 0, 0.6, 1.2, and 1.6 nm were prepared using direct-current magnetron sputtering. Perpendicular magnetic anisotropy, SOT efficiency, and current-driven magnetization reversal were characterized using electrical transport methods based on the anomalous Hall effect. The experimental results indicated that the switching field and magnetic anisotropic field decreased monotonically with an increase in tSm, while the damping-like effective field and effective spin Hall angle (θSHeff) gradually increased. It demonstrates that interface modification with a Sm layer can improve the SOT efficiency and reduce the pinning potential barrier. Owing to the enhanced SOT and reduced pinning field, the critical switching current density (Jc) exhibits a steady decline when increasing tSm. In particular, the lowest Jc of approximately 7.83 × 106 A/cm2 was obtained when tSm was 1.6 nm. X-ray photoelectron spectroscopy revealed that electron transfer occurred between the Co, Pt, and Sm layers, which may be primarily responsible for the enhanced SOT by interface alloying to effectively strengthen the spin Hall effect of Sm and/or Pt. Our results provide a strategy for improving SOT efficiency and reducing Jc by interface alloying in SOT-based spintronic devices.
Cyclic stability of the elastocaloric effect in heterophase [001]-oriented TiNi single crystals
Authors: Surikov N. Yu. , Panchenko E. , Chumlyakov Yu. I. , Marchenko E.
Published: October 2024

The cyclic stability of the elastocaloric effect and the operating parameters (adiabatic cooling value ΔTad, coefficient of performance, operating temperature range) in Ni50.8Ti49.2 and Ni51.5Ti48.5 single crystals oriented along the ⟨001⟩-direction and containing dispersed Ti3Ni4 particles of different sizes were investigated, and the mechanisms of cyclic degradation of the elastocaloric effect were determined. Aged Ni50.8Ti49.2 single crystals containing nanosized Ti3Ni4 particles were shown to possess the optimal combination of operational properties for solid-state cooling. These crystals are characterized by high adiabatic temperature change ΔTad of 16.8–21.4 K over a wide temperature range above 160 K, the highest elastocaloric effect cyclic stability, and high coefficient of performance values up to 27.8. Ni50.8Ti49.2 single crystals with semi-coherent particles (400 nm in size) demonstrate maximum values of ΔTad = 25.3 K; but, they are not feasible for practical applications because of cyclic degradation caused by the formation of residual martensite and dislocations near large particles as well as low coefficient of performance up to 12.7. The use of Ni-rich Ni51.5Ti48.5 crystals can improve the operating characteristics of crystals with semi-coherent Ti3Ni4 particles and achieve high cyclic stability of the elastocaloric effect by strengthening the crystals through an increase in the volume fraction of particles and a decrease in the distance between them.
Promoting effect of CO2 on NiCr oxidation: Atomistic origins based on first principles
Authors: Chen Jianmin , Gao Zifeng , Gong Wenzhuo , Cai Canying , Zhou Guangwen
Published: October 2024

The adsorption and dissociation of CO2 on both perfect and oxygen-deficient α-Cr2O3 (0001) surfaces, alongside the subsequent incorporation of the resulting C into the oxide lattice and its impact on oxide growth, are investigated using first-principles calculations. Our findings reveal that oxygen vacancies significantly enhance CO2 adsorption and promote its stepwise decomposition into C and O atoms. The resulting C can spontaneously dissolve into the oxide lattice through the oxygen vacancies. The presence of bulk dissolved C in the Cr2O3 lattice substantially enhances the formation, migration, and clustering of oxygen vacancies in the bulk. These results provide an atomic-level understanding of how CO2 accelerates the oxidation of chromia-forming alloys, offering microscopic insights for controlling oxide growth and mitigating oxidation-induced degradation of high-temperature alloys.
Perspective on atomic-resolution vibrational electron energy-loss spectroscopy
Authors: Haas Benedikt , Koch Christoph T. , Rez Peter
Published: October 2024

Instrumentation developments in electron energy-loss spectroscopy in the scanning transmission electron microscope one decade ago paved the way for combining milli-electron volt energy resolution in spectroscopy with Ångström-sized electron probes, unlocking unexplored realms for solid state physics at the nanometer scale. The fundamental understanding of the scattering processes involved has made it possible to separate atomically localized signals, providing insight into vibrations at the atomic scale. In this Letter, we outline the experimental, conceptual, and theoretical advances in this field and also make comparisons with tip-based optical techniques before discussing future perspectives of this exciting method. Optimization of dark-field signal collection will play a fundamental role in making this technique more widely applicable to a range of material problems. The benefits of adding momentum-resolution will also be discussed, and a powerful acquisition scheme will be proposed.
Decomposition and prediction of hydrodynamic loads on a floating counter-rotating tidal turbine under surge motion
Authors: Sun Jiyuan , Miao Hongjiang , Wang Pengzhong , Huang Bin , Wang Yu
Published: October 2024

In the actual marine environment, the hydrodynamic characteristics of floating counter-rotating tidal turbines (FCRTTs) are influenced by the motion responses of their carrier platforms. Therefore, accurately analyzing and predicting hydrodynamic loads under the motions of FCRTTs are crucial. In this paper, a fitting formula for hydrodynamic loads of FCRTTs applicable to rotational motion is derived. Then, the effects of surge amplitude, surge frequency, and tip speed ratio on the hydrodynamic loads of an FCRTT are also calculated. It is found that the instantaneous load fluctuation of the rear rotor is more severe than that of the front rotor. However, the average torque of both rotors is similar, which can effectively enhance the operational stability of the FCRTT. Additionally, the hydrodynamic loads are decomposed into average hydrodynamic force, damping force, and added mass force based on the least squares method. A fitting formula for the hydrodynamic loads applicable to different surge conditions is derived, incorporating 11 hydrodynamic coefficients. The results indicate that the damping coefficients nP0 and nT0 play a dominant role in the fluctuation amplitude of the hydrodynamic loads. Finally, an effective and fast prediction model for various hydrodynamic coefficients is successfully established using the three-dimensional radial basis function. The relative errors between the predicted peak values of all performance coefficients and the values calculated using the computational fluid dynamics (CFD) method are within −3.5%. This paper provides important guidance for engineering design and load prediction of FCRTTs. Moreover, the predictive methodology can be extended for application to other single-degree-of-freedom and couple motions.
Topological valley magnons and tunable thermal rectification in staggered Kagome ferromagnets
Authors: Xing Yuheng , Qiu Wenjuan , Zhang Chunwei , Xu Ning , Zhang Haiyang
Published: October 2024

Owing to charge free property, magnon is highly promising to achieve dissipationless transport without Joule heating and, thus, potentially applicable to energy efficient devices. In this paper, using the non-equilibrium Green’s function, we present the bulk-boundary correspondence for magnonic Kagome lattices by studying the edge magnons transport. With staggered exchange interaction and Dzyaloshinskii–Moriya interaction in the Kagome lattices, one can observe valley contrasting magnon Hall effect, which endows magnon transport with the valley degree of freedom and adds a new dimension to regulate magnon excitation. In particular, we demonstrate that the valley splitting in the Kagome lattice enables a tunable single edge chiral transport. Thermal rectification is a direction-dependent asymmetric heat transfer phenomenon; here, we report the tunable thermal rectification by asymmetric nonlinear effect, and it is, indeed, regulated by the Dzyaloshinskii–Moriya interaction direction ( D→−D) and the exchange of J1 and J2 (J1↔J2). Moreover, we show that the topological edge state mainly localizes around edges and leaks into the bulk with oscillatory decay. These give full play to spin and valley degrees of freedom and provide various avenues for information encoding and manipulation based on valley related magnonic flux.
Plasma-enhanced electrowetting-on-dielectrics
Authors: Wang Liang , Li Xiangming , Li Congming , Qiu Yangfan , Wang Zeyu , Yang Qingzhen , Tian Hongmiao , Wang Chunhui , Chen Xiaoliang , Shao Jinyou
Published: October 2024

The wettability of droplets on a dielectric surface can be enhanced by an external electrical signal. Previous research has suggested that such a change in surface wettability is caused by the Maxwell stress concentrated on the three-phase contact line (TPL) of the droplet. Here, we demonstrate that this electromechanical effect cannot fully explain the complex process of droplet contact angle variation. The discharge plasma near the TPL is found to have a significant influence on the contact angle variation. When combined with the Maxwell stress, the plasma discharge can significantly enhance wetting, termed as plasma-enhanced electrowetting-on-dielectrics (PE-EWOD). The conditions for the plasma generation are described, and a phase-like diagram is used to clarify the relationship between PE-EWOD, EWOD, and electrolysis, which is helpful for an adequate control of the wettability through voltage. These findings have important implications for controlling droplet motion in numerous applications, including micro/nano manufacturing, optics, biomedicine, heat dissipation, and electronics.
GaSb-Si3N4 hybrid lasers with precise wavelength control and narrow spectral linewidth based on low-kappa Bragg gratings
Authors: Zhu Chunfan , Wei Jincheng , Geng Zhengqi , Chen Yihang , Yang Chengao , Niu Zhichuan , Wang Ruijun , Yu Siyuan
Published: October 2024

Single-mode semiconductor laser operating near the 2 μm wavelength is of great interest for trace-gas detection, remote sensing, and infrared spectroscopy. Here, we present the 2 μm-wavelength-range laser sources with high output power, precise wavelength control, and narrow spectral linewidth enabled by hybrid integration of a GaSb-based gain chip with silicon nitride Bragg gratings. Low-kappa gratings are used as the laser feedback component to accurately select the lasing wavelength and increase the photon lifetime to achieve narrow-linewidth laser emission. The hybrid laser outputs 33.7 mW optical power with a side mode suppression ratio better than 40 dB near the 2 μm wavelength at room temperature. More than 20 lasers with an excellent wavelength spacing of 2.68 nm is demonstrated. The wavelength deviation is less than ±0.1 nm for all lasers. The intrinsic linewidth of the hybrid integrated external cavity laser with a 4.35 mm long feedback grating is measured to be ∼8.8 kHz using the phase noise demodulation method.
Grain boundaries in single-layer magnetic material CrCl3
Authors: Jian Tao , Guo Yanping , Lu Shuangzan , Deng Jinghao , Cheng Zhengbo , Pan Zemin , Lin Xiaoyu , Zhang Hui , Zhu Chao , Liu Yong , Zhang Chendong
Published: October 2024

Despite the crucial role that grain boundaries (GBs) play in the physical properties of crystalline materials, they have yet to be systematically studied for van der Waals magnetic monolayers. In this study, we investigated the epitaxial growth of monolayer CrCl3 and characterized the prevalent GB types in detail, identifying two dominant categories: those caused by grain rotation and those caused by grain sliding. Our structural and electronic analyses of these GBs revealed significant features associated with them. Notably, the findings include a generally enlarged bandgap at the boundaries and a 1D superstructure with twice the lattice constant at 0° GBs. Our work offers a microscopic perspective that serves as a foundation for understanding the macroscopic properties observed for practical 2D magnetic materials, especially those arising from crystalline imperfections.
Long-time seepage evolution in coal fractures during injection of viscoelastic surfactant fracturing fluids
Authors: Gong Shihui , Ge Zhaolong , Zhou Zhe , Deng Qinglin , Sheng Meiyu , Ye Maolin , Guan Yarui
Published: October 2024

Hydraulic fracturing is widely recognized as a key technology for enhancing coalbed methane production. The fracturing fluid has physicochemical reactions with the coal fractures, along with their duration, critically affecting fracture permeability, thereby determining the effectiveness of the technology. However, the study has not received enough attention. In this study, coal fracture seepage tests were carried out using in situ continuous injection of fracturing fluid. The seepage evolution of viscoelastic surfactant fracturing fluid (VESFF) was investigated at different times (0, 1, 2, 3, 4, and 5 days), and de-ionized water (DW) and potassium chloride solution (KCL) were used for comparison. The results showed that the flow rate increased compared to initial flow rate after VESFF treatment for two to four days, while the flow rate could not be recovered after DW and KCL treatment. The optimal treatment duration for VESFF was two days: marked by a sevenfold increase in the flow rate, an 84% increase in initial hydraulic aperture, and minimal momentum loss. After two more days of VESFF treatment, the pressure gradient and effective confining pressure became greater than 6 MPa/m and 3.5 MPa, respectively, and showed a significant excessive discharge characteristics (β < 0), which resulted from the generation and dilation of microcracks, increasing the number of flow channels due to coupled fluid–mechanical behavior. The degree of flow nonlinearity decreased with increasing VESFF treatment duration and increased with increasing effective confining pressure. These results have profound implications for optimal treatment duration and mechanism of VESFF strengthening coal fracture seepage.
Drag modulation by inertial particles in a drag-reduced turbulent channel flow with spanwise wall oscillation
Authors: Gao Wei , Wang Minmiao , Parsani Matteo
Published: October 2024

Harmonic oscillations of the walls of a turbulent plane channel flow laden with inertial particles are studied by point-particle direct numerical simulation to improve our understanding of the physical mechanism for friction drag reduction. We specify a high wall oscillation amplitude and choose particle parameters that feature a considerable drag-reduction effect. The particle effect on the drag modulation is investigated by varying the wall oscillation period (T+) across a wide range. We find that particles enhance drag reduction for T+≤30 while attenuating it for T+>30. Specifically, we observe drag increase near the optimal oscillation period, i.e., T+=50 and 75. To explore the coupling mechanism of drag modulation by particles and spanwise wall oscillations, we examine the modifications of turbulence and particle statistics. Moreover, the self-sustaining cycle of near-wall turbulence is modulated by wall oscillations and/or particles. We find that the quasi-streamwise vortices are tilted and weakened by wall oscillations while significantly depopulated by particles. The modulated turbulence also affects the near-wall particle accumulation and clustering patterns, which results in different fluid–particle interactions compared with the non-actuated particle-laden channel flow. The mechanism of drag modulation is governed by the competition between reduced fluid Reynolds shear stress and particle stress. To give a quantitative view of the drag modulation, we compare the contributions of different stress components to the friction drag coefficient. Although the fluid Reynolds shear stress is reduced by particles, which corresponds to reduced turbulent kinetic energy production, the particle stress contribution remains significant, especially for the drag-increase case. Furthermore, the anisotropy invariant maps are provided, which show a striking resemblance of increased near-wall turbulence anisotropy as observed in other drag-reduced flows. This suggests that the constraint of increased turbulence anisotropy might be only a necessary but not sufficient condition for achieving drag reduction since this constraint is satisfied in our drag-increase case.
Unraveling abiotic organic synthesis pathways in the mafic crust of mid-ocean ridges
Authors: Nan Jingbo , Peng Xiaotong , Plümper Oliver , ten Have Iris C. , Lu Jing-Guang , Liu Qian-Bao , Li Shao-Lin , Hu Yingjie , Liu Yu , Shen Zhen , Yao Weiqi , Tao Renbiao , Preiner Martina , Luo Yongxiang
Published: October 2024

The aqueous alteration of the oceanic lithosphere provides significant energy that impacts the synthesis and diversity of organic compounds, which are crucial for the deep carbon cycle and may have provided the first building blocks for life. Although abiotic organic synthesis has been documented in mantle-derived rocks, the formation mechanisms and complexity of organic compounds in crustal rocks remain largely unknown. Here, we show the specific association of aliphatic carbonaceous matter with Fe oxyhydroxides in mafic crustal rocks of the Southwest Indian Ridge (SWIR). We determine potential Fe-based pathways for abiotic organic synthesis from CO
2
and H
2
using multimodal and molecular nano-geochemical tools. Quantum mechanical modeling is further employed to constrain the catalytical activity of Fe oxyhydroxides, revealing that the catalytic cycle of hydrogen may play a key role in carbon–carbon bond formation. This approach offers the possibility of interpreting physicochemical organic formation and condensation mechanisms at an atomic scale. The findings expand our knowledge of the existence of abiotic organic carbon in the oceanic crustal rocks and emphasize the mafic oceanic crust of the SWIR as a potential site for low-temperature abiotic organic synthesis.
Transcriptional repression by HDAC3 mediates T cell exclusion fromKrasmutant lung tumors
Authors: McGuire Caroline K. , Meehan Ambryn S. , Couser Evan , Bull Lois , Minor Allegra C. , Kuhlmann-Hogan Alexandra , Kaech Susan M. , Shaw Reuben J. , Eichner Lillian J.
Published: October 2024

Histone Deacetylase 3 (HDAC3) function in vivo is nuanced and directed in a tissue-specific fashion. The importance of HDAC3 inKrasmutant lung tumors has recently been identified, but HDAC3 function in this context remains to be fully elucidated. Here, we identified HDAC3 as a lung tumor cell–intrinsic transcriptional regulator of the tumor immune microenvironment. InKrasmutant lung cancer cells, we found that HDAC3 is a direct transcriptional repressor of a cassette of secreted chemokines, includingCxcl10. Genetic and pharmacological inhibition of HDAC3 robustly up-regulated this gene set in human and mouseKras,LKB1(KL) andKras,p53(KP) mutant lung cancer cells through an NF-κB/p65-dependent mechanism. Using genetically engineered mouse models, we found that HDAC3 inactivation in vivo induced expression of this gene set selectively in lung tumors and resulted in enhanced T cell recruitment at least in part viaCxcl10. Furthermore, we found that inhibition of HDAC3 in the presence of Kras pathway inhibitors dissociatedCxcl10expression from that of immunosuppressive chemokines and that combination treatment of entinostat with trametinib enhanced T cell recruitment into lung tumors in vivo. Finally, we showed that T cells contribute to in vivo tumor growth control in the presence of entinostat and trametinib combination treatment. Together, our findings reveal that HDAC3 is a druggable endogenous repressor of T cell recruitment intoKrasmutant lung tumors.
High-throughput screening for small-molecule stabilizers of misfolded glucocerebrosidase in Gaucher disease and Parkinson’s disease
Authors: Williams Darian , Glasstetter Logan M. , Jong Tiffany T. , Chen Tiffany , Kapoor Abhijeet , Zhu Sha , Zhu Yanping , Calvo Raul , Gehrlein Alexandra , Wong Kimberly , Hogan Andrew N. , Vocadlo David J. , Jagasia Ravi , Marugan Juan J. , Sidransky Ellen , Henderson Mark J. , Chen Yu
Published: October 2024

Glucocerebrosidase (GCase) is implicated in both a rare, monogenic disorder (Gaucher disease, GD) and a common, multifactorial condition (Parkinson’s disease, PD); hence, it is an urgent therapeutic target. To identify correctors of severe protein misfolding and trafficking obstruction manifested by the pathogenic L444P-variant of GCase, we developed a suite of quantitative, high-throughput, cell-based assays. First, we labeled GCase with a small proluminescent HiBiT peptide reporter tag, enabling quantitation of protein stabilization in cells while faithfully maintaining target biology. TALEN-based gene editing allowed for stable integration of a single HiBiT-
GBA1
transgene into an intragenic safe-harbor locus in
GBA1
-knockout H4 (neuroglioma) cells. This GD cell model was amenable to lead discovery via titration-based quantitative high-throughput screening and lead optimization via structure–activity relationships. A primary screen of 10,779 compounds from the NCATS bioactive collections identified 140 stabilizers of HiBiT-GCase-L444P, including both pharmacological chaperones (ambroxol and noninhibitory chaperone NCGC326) and proteostasis regulators (panobinostat, trans-ISRIB, and pladienolide B). Two complementary high-content imaging-based assays were deployed to triage hits: The fluorescence-quenched substrate LysoFix-GBA captured functional lysosomal GCase activity, while an immunofluorescence assay featuring antibody hGCase-1/23 directly visualized GCase lysosomal translocation. NCGC326 was active in both secondary assays and completely reversed pathological glucosylsphingosine accumulation. Finally, we tested the concept of combination therapy by demonstrating synergistic actions of NCGC326 with proteostasis regulators in enhancing GCase-L444P levels. Looking forward, these physiologically relevant assays can facilitate the identification, pharmacological validation, and medicinal chemistry optimization of small molecules targeting GCase, ultimately leading to a viable therapeutic for GD and PD.
A cognitive modelling of translation
Authors: Tao Mei
Published: October 2024

This paper attempts to usher in a cognitive linguistic theory
into (cognitive) translation studies and offers a theoretical model of
translation from the construal perspective. In this construal-based theory,
translators are modelled as construers which are featured by subjectivity, and
meaning decoding and encoding in translation are equated with construal which is
manifested at two levels. At the cognitive level, translators construe the
source text whereas at the linguistic level the construal established by the
translators is packaged in the target language. Translation process involves
translators’ construal operations such as perspective, selection, prominence and
dynamicity, and imagination. Since construal is situated in context, it is
impossible to recreate the construals of the source text author but optimal
construal can be envisioned if the situated contexts for the source text
author(s) as well as that for the target text are best accommodated.
What can the taxonomy of predicative possession in Malwai Punjabi tell us?
Authors: Lu Xiaolong
Published: October 2024

The study aims to examine the syntactic and semantic behaviors of predicative possession (i.e., have-possessive
constructions) in Malwai Punjabi, an underdocumented dialect within the Indo-Aryan language family. Data were collected from
longitudinal online interviews with native speakers as consultants, with audio recordings for transcribed target sentences. The
results revealed that all the alienable possession, either permanent/temporary or abstract/concrete, could be marked by the
postposition koḷ ‘near/with’, whereas inalienable possession, such as whole-part relation and kinship, could not
be encoded using koḷ. The prototypicality model and schema-based metaphors explained why koḷ was
widely used to express alienable possession in Malwai Punjabi. The analysis of companion and proximity schemata
also justified the extended semantics of predicative possession, suggesting a metaphorical mapping of accompaniment and location
onto possession. From a typological angle, the case study can not only provide further evidence for the existence of split
possession but also contribute to a cognitive understanding of predicative possession in relation to other languages.
Syntax, stress and cognitive load, or on syntactic processing in simultaneous interpreting
Authors: Chmiel Agnieszka , Kajzer-Wietrzny Marta , Koržinek Danijel , Jakubowski Dariusz , Janikowski Przemysław
Published: October 2024

This corpus-based study examines the effect of syntactic complexity in the source language on simultaneous interpreters’ cognitive load and stress. Previous studies show contrasting results regarding the source text syntax and cognitive load in interpreting, while the link between syntactic complexity and interpreters’ stress remains unexplored. Our research aims to fill this gap by measuring cognitive load through filled and silent pauses, and stress through fundamental frequency. We evaluated syntactic complexity by calculating dependency distance, i.e., the number of words between syntactically dependent elements. We used PINC, the Polish Interpreting Corpus (Chmiel et al. 2022), as our dataset. We found that higher syntactic complexity in the source text increases stress and cognitive load among interpreters. Additionally, when interpreters produce complex syntax themselves, their stress increases. The study provides empirical evidence for simplification in interpreting and shows that syntactic complexity in interpreters’ own output does not necessarily lead to increased cognitive load.
Manipulation of High-Fidelity Sidebands under Large Detuning by Floquet Technology: Application to Multi-Mode Cooling
Authors: Yang 杨 Xue-Ying 雪滢 , Lin 林 Zi-Dong 子栋 , Mu 穆 Shu-Ying 姝颖 , Wu 吴 Wei 伟 , Wu 吴 Chun-Wang 春旺 , Xie 谢 Yi 艺 , Chen 陈 Ping-Xing 平形
Published: October 2024

The Floquet technology, a powerful way to manipulate quantum states, is employed to drive sidebands transition under large detuning. Our results demonstrate that high fidelities over 99% can be achieved through optimizing suitable modulation frequencies under large detuning. We observe high-fidelity transitions within a high bandwidth by utilizing a single modulation frequency and reveal that this capability is due to the emergence of a flat-band structure in the bandwidth range. The key finding of high-fidelity sideband manipulation under large detuning is experimentally confirmed in nuclear magnetic resonance platform. Finally, we propose a new parallel sideband cooling scheme that enables simultaneous cooling of multiple motional modes. This approach improves the cooling rate compared to conventional schemes with fixed laser frequency and power, and eliminates the need for mode-specific addressing. Our Floquet parallel scheme is applicable to any harmonic oscillator system and is not limited by bandwidth in theory.
Sr-Doping-Modulated Metal-Insulator Transition in NdNiO3 Epitaxial Films
Authors: Ye 叶 Huan 欢 , Hua 华 Enda 恩达 , Xu 许 Fang 方 , Lu 鲁 Jingdi 京迪 , Jin 金 Feng 锋 , Wu 吴 Wenbin 文彬 , Si 司 Liang 良 , Wang 王 Lingfei 凌飞
Published: October 2024

Perovskite-structured nickelates, ReNiO3 (Re = rare earth), have long garnered significant research interest due to their sharp and highly tunable metal-insulator transitions (MITs). Doping the parent compound ReNiO3 with alkaline earth metal can substantially suppress this MIT. Recently, intriguing superconductivity has been discovered in doped infinite-layer nickelates (ReNiO2), while the mechanism behind A-site doping-suppressed MIT in the parent compound ReNiO3 remains unclear. To address this problem, we grew a series of Nd1−x
Sr
x
NiO3 (NSNO, x = 0–0.2) thin films and conducted systematic electrical transport measurements. Our resistivity and Hall measurements suggest that Sr-induced excessive holes are not the primary reason for MIT suppression. Instead, first-principles calculations indicate that Sr cations, with larger ionic radius, suppress breathing mode distortions and promote charge transfer between oxygen and Ni cations. This process weakens Ni–O bond disproportionation and Ni2+/Ni4+ charge disproportionation. Such significant modulations in lattice and electronic structures convert the ground state from a charge-disproportionated antiferromagnetic insulator to a paramagnetic metal, thereby suppressing the MIT. This scenario is further supported by the weakened MIT observed in the tensile-strained NSNO/SrTiO3(001) films. Our work reveals the A-side doping-modulated electrical transport of perovskite nickelate films, providing deeper insights into novel electric phases in these strongly correlated nickelate systems.
Spin Dynamics and Phonons in Chromites CoCr2O4 and MnCr2O4
Authors: Xu 徐 Wei 威 , Lin 林 Gaoting 高庭 , Shu 舒 Mingfang 明方 , Jiao 焦 Jinlong 金龙 , Zhu 朱 Jinfeng 金峰 , Ren 任 Qingyong 清勇 , Le Manh Duc , Luo 罗 Xuan 轩 , Sun 孙 Yuping 玉平 , Liu 刘 Yi 毅 , Qu 屈 Zhe 哲 , Zhou 周 Haidong 海东 , Gao 高 Shang 尚 , Ma 马 Jie 杰
Published: October 2024

Spinel compounds are of great interest in both fundamental and application-oriented perspectives due to the geometric magnetic frustration inherent to their lattice and the resulting complex magnetic states. Here, we applied x-ray diffraction, magnetization, heat capacity and powder inelastic neutron scattering measurements, along with theoretical calculations, to study the exotic properties of chromite-spinel oxides CoCr2O4 and MnCr2O4. The temperature dependence of the phonon spectra provides an insight into the correlation between oxygen motion and the magnetic order, as well as the magnetoelectric effect in the ground state of MnCr2O4. Moreover, spin-wave excitations in CoCr2O4 and MnCr2O4 are compared with Heisenberg model calculations. This approach enables the precise determination of exchange energies and offers a comprehensive understanding of the spin dynamics and relevant exchange interactions in complicated spiral spin ordering.
Multi-layer feature fusion and attention enhancement for fine-grained vehicle recognition research
Authors: Zhang Shouyang , Zhang Yong
Published: October 2024

Vehicle recognition technology is widely applied in automatic parking, traffic restrictions, and public security investigations, playing a significant role in the construction of intelligent transportation systems. Fine-grained vehicle recognition seeks to surpass conventional vehicle recognition by concentrating on more detailed sub-classifications. This task is more challenging due to the subtle inter-class differences and significant intra-class variations. Localization-classification subnetworks represent an efficacious approach frequently employed for this task, but previous research has typically relied on CNN deep feature maps for object localization, which suffer from the low resolution, leading to poor localization accuracy. The multi-layer feature fusion localization method proposed by us fuses the high-resolution feature map of the shallow layer of CNN with the deep feature map, and makes full use of the rich spatial information of the shallow feature map to achieve more precise object localization. In addition, traditional methods acquire local attention information through the design of complex models, frequently resulting in regional redundancy or information omission. To address this, we introduce an attention module that adaptively enhances the expressiveness of global features and generates global attention features. These global attention features are then integrated with object-level features and local attention cues to achieve a more comprehensive attention enhancement. Lastly, we devise a multi-branch model and employ the aforementioned object localization and attention enhancement methods for end-to-end training to make the multiple branches collaborate seamlessly to adequately extract fine-grained features. Extensive experiments conducted on the Stanford Cars dataset and the self-built Cars-126 dataset have demonstrated the effectiveness of our method, achieving a leading position among existing methods with 97.7% classification accuracy on the Stanford Cars dataset.
Simple extraction method of magnetic hysteresis curve from measurement data
Authors: Rezki Mohamed , Bensaid Samir , Houassine Hamza
Published: October 2024

The main target of this study is to investigate a simple way to extract the magnetic material hysteresis curve using a new numerical integration method. The most used method for extracting the hysteresis loop involves integrating the measured voltage signal through a capacitor. This method is a hardware and analogical integration which requires precise dimensioning of the integration capacitor. Moreover, it is imprecise for the nonsinusoidal voltage signal. In this paper, one has interested to all types of voltage signals (with and without harmonics). The proposed method allows to directly integrate all signal waveforms with a good accuracy and low cost materials and times. The method is implemented in OCTAVE open source. The experimental acquisition is carried out using a testing bench to measure the transformer’s primary current and secondary voltage signals. The proposed method is first validated on the primitives of the nonsinusoidal usual signals such as triangle and square signals. Then it is applied to extract the hysteresis loop of single phase transformer. The area of hysteresis loop which gives the iron losses is compared to the measured one given by a Wattmeter for several voltages. The computed and measured iron losses are practically identical. Thus, the validation of the proposed approach is performed and the finding of this research may serve as an alternative technique to direct and fast determining the hysteresis loop with a good accuracy.
High-precision spatial measurement method of accelerator pre-alignment based on multiple total stations
Authors: Xing Yubo , Dong Lan , Wang Tong , Liang Jing , Ma Na , Ke Zhiyong , He Zhenqiang , Li Bo , Men Lingling , Lu Shang , Wang Xiaolong , Yang Zhen
Published: October 2024

With the development of accelerator technology, the scale of accelerators is becoming larger, ranging from hundreds of meters to several kilometers. For stable operation of accelerators, high-precision alignment, positioning, and installation are crucial. Installing all equipment inside the tunnel poses safety risks as personnel would be in a closed environment with potential radiation exposure for prolonged periods. To address the challenges of long adjustment and maintenance periods inside the tunnel due to the installation of equipment for large-scale accelerators, most accelerator devices under construction or in research have pre-alignment assemblies. Each assembly consists of a certain number of magnets distributed on girders. The magnets in one unit are pre-aligned with high precision in the laboratory and then transported to the tunnel. Aligning the entire magnet girder can significantly improve installation efficiency inside the tunnel. To meet the pre-alignment accuracy requirement of 10 μm in the horizontal and vertical directions for the magnet units in the high energy photon source (HEPS) storage ring, a system for high-precision pre-alignment of accelerator units using four total stations for angle observation has been designed in this paper. By employing different instrument layout configurations and incorporating reliable distance benchmarks, high-precision pre-alignment of the magnet are achieved. By arranging targets and utilizing recognition for automatic targeting, real-time point calculations during pre-alignment enhance efficiency. Subsequently, based on this system, pre-alignment simulation calculations and experimental verification of eight magnet focusing–defocusing units in the HEPS storage ring are conducted and ultimately realizing the 10 μm transverse and vertical pre-alignment measuring error within the units. This method, based on high-precision measurements in a small-scale space, reduces the period required for personnel on-site and improves pre-alignment efficiency. It also provides a reference for pre-alignment of multiple magnet units in large accelerators such as the Southern Advanced Photon Source and Circular Electron Positron Collider.
Electrically conductive nanomaterials: transformative applications in biomedical engineering—a review
Authors: Banik Oindrila , Salve Amol Lalchand , Kumar Prasoon , Kumar Santosh , Banoth Earu
Published: October 2024

In recent years, significant advancements in nanotechnology have improved the various disciplines of scientific fields. Nanomaterials, like, carbon-based (carbon nanotubes, graphene), metallic, metal oxides, conductive polymers, and 2D materials (MXenes) exhibit exceptional electrical conductivity, mechanical strength, flexibility, thermal property and chemical stability. These materials hold significant capability in transforming material science and biomedical engineering by enabling the creation of more efficient, miniaturized, and versatile devices. The indulgence of nanotechnology with conductive materials in biological fields promises a transformative innovation across various industries, from bioelectronics to environmental regulations. The conductivity of nanomaterials with a suitable size and shape exhibits unique characteristics, which provides a platform for realization in bioelectronics as biosensors, tissue engineering, wound healing, and drug delivery systems. It can be explored for state-of-the-art cardiac, skeletal, nerve, and bone scaffold fabrication while highlighting their proof-of-concept in the development of biosensing probes and medical imaging. This review paper highlights the significance and application of the conductive nanomaterials associated with conductivity and their contribution towards a new perspective in improving the healthcare system globally.
The therapeutic potential of reduced graphene oxide in attenuating cuprizone-induced demyelination in mice
Authors: Rizoli Cintia , dos Santos Nathalia Medina , Maróstica Júnior Mário Roberto , da Cruz-Höfling Maria Alice , Mendonça Monique Culturato Padilha , de Jesus Marcelo Bispo
Published: October 2024

Reduced graphene oxide (rGO) has unique physicochemical properties that make it suitable for therapeutic applications in neurodegenerative scenarios. This study investigates the therapeutic potential of rGO in a cuprizone-induced demyelination model in mice through histomorphological techniques and analysis of biochemical parameters. We demonstrate that daily intraperitoneal administration of rGO (1 mg ml−1) for 21 days tends to reduce demyelination in the Corpus callosum by decreasing glial cell recruitment during the repair mechanism. Additionally, rGO interferes with oxidative stress markers in the brain and liver indicating potential neuroprotective effects in the central nervous system. No significant damage to vital organs was observed, suggesting that multiple doses could be used safely. However, further long-term investigations are needed to understand rGO distribution, metabolism, routes of action and associated challenges in central neurodegenerative therapies. Overall, these findings contribute to the comprehension of rGO effects in vivo, paving the way for possible future clinical research.
Artificial synapses based on HfOx/TiOy memristor devices for neuromorphic applications
Authors: Özkal Bünyamin , Al-Jawfi Nora Ali Abdo Saleh , Ekinci Gökhan , Rameev Bulat Z , Khaibullin Rustam I , Kazan Sinan
Published: October 2024

As a result of enormous progress in nanoscale electronics, interest in artificial intelligence (AI) supported systems has also increased greatly. These systems are typically designed to process computationally intensive data. Parallel processing neural network architectures are particularly noteworthy for their ability to process dense data at high speeds, making them suitable candidates for AI algorithms. Due to their ability to combine processing and memory functions in a single device, memristors offer a significant advantage over other electronic platforms in terms of area scaling efficiency and energy savings. In this study, single-layer and bilayer metal–oxide HfO
x
and TiO
y
memristor devices inspired by biological synapses were fabricated by pulsed laser and magnetron sputtering deposition techniques in high vacuum with different oxide thicknesses. The structural and electrical properties of the fabricated devices were analysed using x-ray reflectivity, x-ray photoelectron spectroscopy, and standard two-probe electrical characterization measurements. The stoichiometry and degree of oxidation of the elements in the oxide material for each thin film were determined. Moreover, the switching characteristics of the metal oxide upper layer in bilayer devices indicated its potential as a selective layer for synapse. The devices successfully maintained the previous conductivity values, and the conductivity increased after each pulse and reached its maximum value. Furthermore, the study successfully observed synaptic behaviours with long-term potentiation, long-term depression (LTD), paired-pulse facilitation, and spike-timing-dependent plasticity, showcasing potential of the devices for neuromorphic computing applications.
Geometric analysis of fast-slow PDEs with fold singularities via Galerkin discretisation
Authors: Engel Maximilian , Hummel Felix , Kuehn Christian , Popović Nikola , Ptashnyk Mariya , Zacharis Thomas
Published: October 2024

We study a singularly perturbed fast-slow system of two partial differential equations (PDEs) of reaction-diffusion type on a bounded domain via Galerkin discretisation. We assume that the reaction kinetics in the fast variable realise a generic fold singularity, whereas the slow variable takes the role of a dynamic bifurcation parameter, thus extending the classical analysis of the singularly perturbed fold. Our approach combines a spectral Galerkin discretisation with techniques from geometric singular perturbation theory which are applied to the resulting high-dimensional systems of ordinary differential equations. In particular, we show the existence of invariant slow manifolds in the phase space of the original system of PDEs away from the fold singularity, while the passage past the singularity of the Galerkin manifolds obtained after discretisation is described by geometric desingularisation, or blow-up. Finally, we discuss the relation between these Galerkin manifolds and the underlying slow manifolds.
Multi-layered morphing soft structure with high-performance embedded electrothermal artificial muscles along with touch and temperature sensors
Authors: Singh Matharu Pawandeep , Song Yuyang , Gandhi Umesh , Tadesse Yonas
Published: October 2024

In this paper, we present a novel multilayered morphing structure, having similar topology resembling the structures found in nature to grasp delicate objects effectively as well as sense contact force and temperature. The structure consists of two actuation layers, two U-shaped cooling channel layers, piezoelectric based touch sensors and temperature sensors. Employing shape memory alloy (SMA) spring actuators for bending and twisted and coiled polymer fishing line with nichrome (TCPFL
NMC) artificial muscles for antagonistic return, the soft silicone-based composite skin exhibits unique capabilities of large bidirectional movement, avoid rigid passive springs for return motion, soft grasping, safe interaction with humans, and ease fabrication. The SMA (0.38 mm wire diameter) serves as relatively fast actuating muscle and the TCPFL
NMC (0.8 mm fiber diameter) as a slow actuating (considering mainly heating cycle), which was programmed/designed to mimic the fast and slow twitching muscles found in nature. Bending and return operations of skin samples of length 100 mm and thickness of 9 mm, with three different widths 20 mm, 25 mm, 30 mm, were experimentally studied. The 25 mm wide multilayered soft skin demonstrated cyclic actuation with a maximum bending angle of ∼70°, which was attributed due to the active cooling. The fluidic channels for active cooling were fabricated using 3D printed PVA tubes, casting within the silicone in a mold and subsequently dissolving in a circulating water. The study also included the integration and voltage response of mini-piezodisk sensor PIC255 having a diameter of 2 mm and thickness of 0.15 mm, which was embedded at different depths within the silicone (on the surface, 1 mm depth and 2 mm depth). The multilayered soft skin was also able to detect the temperature of the object during grasping, suggesting its potential application as a soft gripper in robotic systems.