bluuebunny/crossref_metadata_2025 huggingface dataset:
Progress in torrefaction pretreatment for biomass gasification
Authors: Zhou Quanhui , Shen Yafei , Gu Xuehong
Published: August 2024

This paper reports on the dry and wet torrefaction pretreatment for upgrading low-rank biomass sources to enhance the gasification process with the benefits of H2-rich syngas production and tar reduction.
Lithium-ion batteries: direct solid sampling for characterisation of black mass recyclates using graphite furnace atomic absorption spectrometry
Authors: Dommaschk Maria , Sieber Tim , Acker Jörg
Published: August 2024

A straightforward, efficient and robust method was developed in this study to analyse the metal content of complex recyclates from cathode coatings (LiNixMnyCo1−x−yO2) recovered from spent lithium-ion batteries.
Assembled mechanical metamaterials with integrated functionalities of programmable multistability and multitransition behaviors
Authors: He Jian , Wang Yaohui , Shen Zhengquan , Xia Liang , Xiong Yi
Published: August 2024

We propose a systematic strategy to create multistable metamaterials with function-oriented multitransition behaviors to satisfy diverse application scenarios by the replacement of designed contact block (CB) plates.
Engineering in situ growth of Au nanoclusters on hydrophilic paper fibres for fluorescence calligraphy-based chemical logic gates and information encryption
Authors: Luo Jun Jiang , Guo Dun Ying , Qu Zi Bo , Luo Hong Qun , Li Nian Bing , Zou Hao Lin , Li Bang Lin
Published: August 2024

The staining of modified papers with HAuCl4 solutions enables the in situ growth of Au nanoclusters, and the improved fluorescence stability and uniform material distribution facilitate the chemical logic gates and information encryption systems.
A macrocycle-based new organometallic nano-vessel towards sustainable C2-selective arylation of free indole in water
Authors: Mandal Subham , Sarkar Piyali , Ghosh Pradyut
Published: August 2024

C2-selectivity of unsubstituted indole over facile C3-substitution is attempted by utilizing the π-cavity of a nano-vessel made up of a palladium complex of an amino-ether heteroditopic macrocycle.
Indoline hemiaminals: a platform for accessing anthranilic acid derivatives through oxidative deformylation
Authors: Tokushige Keisuke , Kobori Yuito , Asai Shota , Abe Takumi
Published: August 2024

Herein, we introduce a new synthetic protocol using 2-aminobenzoyl surrogates, allowing concise entry to decorated 2-aminobenzoyl derivatives in the absence of transition metals, acid chlorides, and specific reagents.
Air promotes efficient and selective CO2 photoreduction with a molecule/semiconductor hybrid photocatalyst: the significant role of simultaneous photodegradation of organic pollutants
Authors: Hong Xinyue , Zhu Yuru , Chao Duobin
Published: August 2024

A molecule/semiconductor hybrid photocatalyst, consisting of carbon nitride integrated with a molecular Ni(ii)–terpyridine complex, has been employed for air-promoted CO2 photoreduction with the simultaneous photodegradation of tetracycline.
Post-functionalization of end-capped twistacenes with pyrene units
Authors: Wang Sujuan , Ye Tongtong , Xiao Jinchong
Published: August 2024

This review covers recent advances in post-functionalization of twistacenes to realize polyacenes, chiral nanographenes and their semiconductor properties, and emphasizing a promising future for constructing chiral nanotubes.
Design and characterisation of casein coated and drug loaded magnetic nanoparticles for theranostic applications
Authors: Wenck Christina , Meier Nils , Heinrich Eilien , Grützner Verena , Wiekhorst Frank , Bleul Regina
Published: August 2024

Magnetic protein-coated, drug-loaded nanohybrids have huge potential in future cancer theranostics for real-time monitored drug delivery.
In situ growth of CaMoO4 on electropolymerized PANI as a hybrid electrocatalyst for enhanced oxygen evolution
Authors: Garg Nitika , Ganguli Ashok K.
Published: August 2024

Our studies demonstrate the potential of inorganic oxide/conductive polymer composite electrode prepared via binder-free growth for applications in electrochemical water splitting and energy conversion.
Zinc metal complexes synthesized by a green method as a new approach to alter the structural and optical characteristics of PVA: new field for polymer composite fabrication with controlled optical band gap
Authors: Muhammad Dana S. , Aziz Dara M. , Aziz Shujahadeen B.
Published: August 2024

The current study employed a novel approach to design polymer composites with modified structural and declined optical band gaps.
Observing bioorthogonal macrocyclizations in the nuclear envelope of live cells using on/on fluorescence lifetime microscopy
Authors: Pim Sebastian , Bourgès Anaïs C. , Wu Dan , Durán-Sampedro Gonzalo , Garre Massimiliano , O'Shea Donal F.
Published: August 2024

Bioorthogonal FLIM: real-time watching macrocyclizations take place within the nuclear envelope through continuous recording of fluorescence lifetimes while fluorophore intensities and wavelengths remain comparatively unchanged.
Study on the impact of battery pack arrangement on temperature uniformity distribution
Authors: Ji ZhongXing , Zhang Chao
Published: August 2024

Optimizing structural parameters (channel width, inclination angle, cell gap) improves lithium-ion battery pack thermal performance, enhancing safety and extending lifespan.
Counter ion-regulated heterostructured Co@Fe-based core@shell materials: as remarkable bifunctional electrodes for green H2 production
Authors: Rajeshkhanna Gaddam , Borah Apurba , Singh Thangjam Ibomcha , Nguyen Thanh Hai , Dinh Van An , Kim Nam Hoon , Lee Joong Hee
Published: August 2024

The exceptional bifunctional catalytic activity of Co@Fe-based core@shell materials, when Co2P@Fe2P/NF was used as both the anode and cathode, achieving outstanding performance in alkaline water splitting, excelling in both the OER and the HER.
Defects in kesterite materials towards high-efficiency solar cells: origin, impact, characterization, and engineering
Authors: Wang Lijing , Ban Jintang , Han Litao , Zhou Zhengji , Zhou Wenhui , Kou Dongxing , Meng Yuena , Qi Yafang , Yuan Shengjie , Wu Sixin
Published: August 2024

The origins and effects of defects in kesterite absorbers as well as commonly used defect characterization and passivation techniques are summarized, and critical insights toward high-efficiency CZTSSe solar cells are presented.
Ultrathin iridium carbonyl formate for efficient and durable acidic oxygen evolution electrocatalysis
Authors: Guo Jian Wei , Mao Fangxin , Fang Song Ru , Lin Hao Yang , Wang Huan , Li Wen Jing , Yuan Hai Yang , Yang Shuang , Liu Peng Fei , Yang Hua Gui
Published: August 2024

Iridium carbonyl formate nanoflakes were fabricated swiftly via a liquid-phase microwave method, showcasing a remarkable acidic water oxidation performance and sustaining operation in proton exchange membrane electrolysis at 1.0 A cm−2 for 100 h.
Small intestine submucosa decorated 3D printed scaffold accelerated diabetic bone regeneration by ameliorating the microenvironment
Authors: Tan Jie , Chen Zecai , Xu Zhen , Huang Yafang , Qin Lei , Long Yufeng , Wu Jiayi , Yang Hantao , Chen Xuandu , Yi Weihong , Hang Ruiqiang , Guan Min , Wang Huaiyu , Gao Ang , Yang Dazhi
Published: August 2024

3D-printed PLGA/hydroxyapatite/icariin scaffolds with small intestine submucosa coating offer immunoregulatory abilities, enhance angiogenesis and osteogenesis, and show promise for treating bone defects in diabetic patients.
Grain boundary effect unveiled in monolayer MoS2 for photonic neuromorphic applications
Authors: Krishnan K Navaneeth , Sathyanarayana Sandaap , Das Bikas C.
Published: August 2024

This study explores grain boundaries (GBs) in monolayer MoS2, highlighting their impact on photonic memristor functions. GB-free MoS2 shows better photodetection, while GBs, though slower in speed, enable adaptive learning and synaptic behaviors.
Markers of agonality in the discourse
Authors: Tambieva Fatima , Dzeitova Khaifa , Yusupova Svetlana
Published: August 2024

The article is devoted to one of the topical problems of linguistics - verbal agonality. Verbal agonality is an integral part of interpersonal communication and expresses rivalry, aiming to achieve victory by any communicative means, including psychological and/or verbal aggression. Verbal violence is common in many communicative situations and in different social groups, it can occur between people of equal or different status; it is expressed by speech acts of different stylistics. One of the ways of speech interaction, namely, the interactive way is considered discourse, since from the point of view of the communicative-pragmatic aspect, many modern linguistic concepts treat discourse as an interdisciplinary category. The semantic integrity of discourse consists of semantically structural components, one of them can be agonality. The communicative dialectic allows through agonality to express aggression, insult and other feelings as a result of communication, as well as feelings that have not received their completion, that is, they express neither agreement nor disagreement.
Enhanced fault localization in multi-terminal transmission lines using novel machine learning
Authors: Wang Yingyun , Qi Xiaoxia , Chen Yang
Published: August 2024

Accurate fault location on transmission lines is paramount for ensuring the reliable and efficient operation of the electricity grid, which underpins every aspect of modern society. Existing fault localization methods for transmission lines often face shortcomings, particularly in scenarios involving multi-terminal transmission lines, where complexities arise due to dispersed generations and intricate network configurations. Traditional approaches may struggle to provide accurate fault localization, impacting the reliability and efficiency of the electricity grid. Research provide a unique fault localization technique in this article depends on Phasor Measurement Units (PMUs) and Bidirectional Gradient Boost Random Forest (BDGB-RF) machine learning technique to address these challenges. The proposed method offers several advantages over traditional methods, including enhanced accuracy and efficiency. By leveraging PMU data and BDGB-RF, the method provides a two-phase fault localization strategy, incorporating fault line selection based on nodal current imbalance and subsequent fault distance determination. Simulation results demonstrate the effectiveness of the proposed approach, achieving up to 97% accuracy in the majority of studied scenarios, even under different tapping configurations. The adoption of this approach could significantly impact the practices of experts in the field, facilitating more reliable fault detection and localization in complex transmission line networks. This, in turn, can contribute to the resilience and stability of power systems, ultimately improving grid reliability and minimizing downtime.
Channel assisted noise propagation in a two-step cascade
Authors: Nandi Mintu , Chattopadhyay Sudip , Bandyopadhyay Somshubhro , Banik Suman K.
Published: August 2024

Signal propagation in biochemical networks is characterized by the inherent randomness in gene expression and fluctuations of the environmental components, commonly known as intrinsic and extrinsic noise, respectively. We present a theoretical framework for noise propagation in a generic two-step cascade (S→X→Y) regarding intrinsic and extrinsic noise. We identify different channels of noise transmission that regulate the individual and the overall noise properties of each component. Our analysis shows that the intrinsic noise of S alleviates the general noise and information transmission capacity along the cascade. On the other hand, the intrinsic noise of X and Y acts as a bottleneck of information transmission. We also show a hierarchical relationship among the intrinsic noise levels of S, X, and Y, with S exhibiting the highest level of intrinsic noise, followed by X and then Y. This hierarchy is preserved within the two-step cascade, facilitating the highest information transmission from S to Y via X.
Mode-dependent scaling of nonlinearity and linear dynamic range in a NEMS resonator
Authors: Ma M. , Welles N. , Svitelskiy O. , Yanik C. , Kaya I. I. , Hanay M. S. , Paul M. R. , Ekinci K. L.
Published: August 2024

Even a relatively weak drive force is enough to push a typical nanomechanical resonator into the nonlinear regime. Consequently, nonlinearities are widespread in nanomechanics and determine the critical characteristics of nanoelectromechanical systems' (NEMSs) resonators. A thorough understanding of the nonlinear dynamics of higher eigenmodes of NEMS resonators would be beneficial for progress, given their use in applications and fundamental studies. Here, we characterize the nonlinearity and the linear dynamic range (LDR) of each eigenmode of two nanomechanical beam resonators with different intrinsic tension values up to eigenmode n = 11. We find that the modal Duffing constant increases as n4, while the critical amplitude for the onset of nonlinearity decreases as 1/n. The LDR, determined from the ratio of the critical amplitude to the thermal noise amplitude, increases weakly with n. Our findings are consistent with our theory treating the beam as a string, with the nonlinearity emerging from stretching at high amplitudes. These scaling laws, observed in experiments and validated theoretically, can be leveraged for pushing the limits of NEMS-based sensing even further.
Visual depiction and numerical characterization of intricate flow in triply periodic minimal surface foams
Authors: Li Jiaxuan , Yang Yang , Zhu Xun , Ye Dingding , Chen Rong , Liao Qiang
Published: August 2024

Benefiting from the structural specificity and programmability, the bioinspired triply periodic minimal surfaces (TPMSs) bring excellent physicochemical properties that are distinct from conventional topologies. Especially with the rapid development of additive manufacturing and high-performance computing capacities, function-oriented design and synthesis of smart TPMS materials or devices have become feasible. Therefore, understanding the flow characterizations induced by TPMS foams is of remarkable importance to the successful design and practical operation. However, the in-depth studies and theoretical guidance on the relationship between structure and flow characterizations of TPMS foams are still limited. In this study, an Eulerian and Lagrangian coupled model is developed to investigate the internal flow behaviors and flow regime transition mechanism from creeping to inertial flow in four representative TPMS foams. The simulation accuracy is then validated by a high-resolution pore-scale flow field observation. Results show that the flow morphology and pressure drop characteristics are highly influenced by TPMS geometry and Re. Among which, Schwarz Diamond (D), Schoen Gyroid (G), and Fischer-Koch S (S) foams are more susceptible to radial flow disturbance, while Schoen inverted Weissenberg periodic foam to axial flow disturbance. In addition, higher porosities delay the transition to transitional regime of the flow. This work establishes firm theoretical and methodological foundations for the customization and intelligent development of bioinspired TPMS foam materials in broad fluidic applications.
Designing a magnetic micro-robot for transporting stiff filamentous microcargo
Authors: Ghadami Sepehr , Shum Henry
Published: August 2024

In recent years, the medical industry has witnessed a growing interest in developing minimally invasive procedures, with magnetic micro-robots emerging as a promising approach. These micro-robots possess the ability to navigate through various media, including viscoelastic and non-Newtonian fluids, enabling targeted drug delivery and medical interventions. Many designs that have been proposed to date employ a contact-based method for transporting a payload. Undesired adhesion between the cargo and the carrier can make release at the target site problematic. The primary objective of our current work is to modify the design of magnetically actuated helical micro-robots to enable transportation of cargo in Newtonian fluids without requiring contact between the robot and the cargo. We conduct a comprehensive study on the shape and geometrical parameters of the helical micro-robot, specifically focusing on its capability to transport passive filaments that are rigid to thermal noise. Based on our analysis, we propose a novel design consisting of three helical sections with alternating handedness, including two pulling and one pushing microhelices. We first focus on naturally straight filaments but also show that the micro-robot can capture filaments with intrinsic curvature and those with a spherical payload attached at one end. Our findings offer valuable insights into the physics of helical micro-robots and their potential for medical procedures and drug delivery. Furthermore, the proposed non-contact method for delivering filamentous cargo could lead to the development of more effective micro-robots for medical applications.
TW-scale few-cycle short-wave infrared laser based on nonlinear compression in a large-core gas-filled hollow core fiber
Authors: Feng Renyu , Qian Junyu , Peng Yujie , Li Yanyan , Li Wenkai , Liu Yunpeng , Leng Yuxin , Li Ruxin
Published: August 2024

In this Letter, we present the generation of terawatt-scale few-cycle short-wave infrared (SWIR) lasers using nonlinear compression in a large-core gas-filled hollow core fiber. Through the experimental verification, we investigate the energy scaling properties and nonlinear pulse propagation in the argon-filled hollow core fiber. At static pressure, the system delivers pulses with 5.55 mJ/9.04 fs at a central wavelength of 1.45 μm, resulting in a peak power of about 0.5 TW. Subsequently, based on the chirped input pulses and pressure gradient, the system delivers terawatt-scale two-cycle SWIR pulses with 9.52 mJ/10.65 fs, resulting in a record peak power of about 0.7 TW. This study marks a crucial advancement in the field of SWIR ultra-intense, ultrashort pulse nonlinear interaction platforms. This high-energy, few-cycle SWIR source has significant applications in high-intensity THz radiation, x-ray generation, and other fields of strong-field physics.
Investigation of wake dynamics near the cylinder with the variation of length-to-diameter ratio
Authors: Bulbule Shreyas , Kumar Pankaj , Singh Santosh Kumar
Published: August 2024

The study investigates the impact of drag forces on underwater pipeline structures at junctions where diameter changes occur, utilizing three-dimensional numerical simulations to analyze flow patterns around dual-step cylinders at a Reynolds number of 5000. The numerical model is validated against benchmark studies for a plain circular cylinder at heating condition, demonstrating strong agreement. Subsequently, cylinder temperatures were varied to assess their influence on drag force. The study further explores the effect of varying the aspect ratio L/D from 1 to 3 on drag reduction. Analysis of the flow structures is conducted, focusing on vortex patterns, velocity fields, and force coefficients surrounding the cylinders. Additionally, streamwise and crosswise velocities are analyzed at different sectional planes of the step cylinder. Results indicate that the drag force diminishes with increasing aspect ratio, correlating with formation length (Lf). At lower aspect ratios, step-induced vortices migrate toward the wall, while at higher aspect ratios, they drift midway. This research provides insights for designing stepped diameter cylinder systems in the subcritical regime, contributing to optimized underwater pipeline structures.
Improving the precision of forces in real-space pseudopotential density functional theory
Authors: Roller Deena , Rappe Andrew M. , Kronik Leeor , Hellman Olle
Published: August 2024

The high-order finite difference real-space pseudopotential density functional theory (DFT) approach is a valuable method for large-scale, massively parallel DFT calculations. A significant challenge in the approach is the oscillating “egg-box” error introduced by aliasing associated with a coarse grid spacing. To address this issue while minimizing computational cost, we developed a finite difference interpolation (FDI) scheme [Roller et al., J. Chem. Theory Comput. 19, 3889 (2023)] as a means of exploiting the high resolution of the pseudopotential to reduce egg-box effects systematically. Here, we show an implementation of this method in the PARSEC code and examine the practical utility of the combination of FDI with additional methods for improving force precision and/or reducing its computational cost, including orbital-based forces, compensating charges (namely, adding and subtracting a judiciously chosen charge density such that the total density is unaltered), and a modified spatial domain in which the real-space grid is defined. Using selected small molecules, as well as metallic Li, as test cases, we show that a combination of all four aspects leads to a significant reduction in computational cost while retaining a high level of precision that supports accurate structures and vibrational spectra, as well as stable and accurate molecular dynamics runs.
Below the surface: Unraveling the intricacies of the nonlinear optical properties of aluminum through bound electrons
Authors: Scalora M. , Hallman K. , Mukhopadhyay S. , Pruett S. , Zappa D. , Comini E. , de Ceglia D. , Vincenti M. A. , Akozbek N. , Trull J. , Cojocaru C.
Published: August 2024

By uncovering novel aspects of second harmonic generation in aluminum, we show that there are unusual and remarkable consequences of resonant absorption, namely an unexpectedly critical role that bound electrons play for light–matter interactions across the optical spectrum, suggesting that a different basic approach is required to fully explain the physics of surfaces. We tackle an issue that is never under consideration given the generic hostile conditions to the propagation of light under resonant absorption. Unlike most noble metals, aluminum displays Lorentz-like behavior and interband transitions centered near 810 nm, thus splitting the plasmonic range in an atypical manner and setting its linear and nonlinear optical properties apart. Studies of aluminum nanostructures having complex topologies abound, as do reported inconsistencies in the linear spectral response of surface plasmons and harmonic generation. Our experimental observations of second harmonic generation from aluminum nanolayers show that bound electrons are responsible for a unique signature neither predicted nor observed previously: a hole in the second harmonic spectrum. A hydrodynamic-Maxwell theory explains these findings exceptionally well and becomes the basis for renewed studies of surface physics.
Artificial neural network aided vapor–liquid equilibrium model for multi-component high-pressure transcritical flows with phase change
Authors: Srinivasan Navneeth , Yang Suo
Published: August 2024

In this work, an artificial neural network (ANN) aided vapor–liquid equilibrium (VLE) model is developed and coupled with a fully compressible computational fluid dynamics (CFD) solver to simulate the transcritical processes occurring in high-pressure liquid-fueled propulsion systems. The ANN is trained in Python using TensorFlow, optimized for inference using Open Neural Network Exchange Runtime, and coupled with a C++ based CFD solver. This plug-and-play model/methodology can be used to convert any multi-component CFD solver to simulate transcritical processes using only open-source packages, without the need of in-house VLE model development. The solver is then used to study high-pressure transcritical shock-droplet interaction in both two- and four-component systems and a turbulent temporal mixing layer (TML), where both qualitative and quantitative agreement (maximum relative error less than 5%) is shown with respect to results based on both direct evaluation and the state-of-the-art in situ adaptive tabulation (ISAT) method. The ANN method showed a 6 times speed-up over the direct evaluation and a 2.2-time speed-up over the ISAT method for the two-component shock-droplet interaction case. The ANN method is faster than the ISAT method by 12 times for the four-component shock-droplet interaction. A 7 times speed-up is observed for the TML case for the ANN method compared to the ISAT method while achieving a data compression factor of 2881. The ANN method also shows intrinsic load balancing, unlike traditional VLE solvers. A strong parallel scalability of this ANN method with the number of processors was observed for all the three test cases. Code repository for 0D VLE solvers, and C++ ANN interface—https://github.com/UMN-CRFEL/ANN_VLE.git.
A coupled smoothed particle hydrodynamics–peridynamics model for two-dimensional hydroelastic water entry
Authors: Jing Chongyang , Wang Yongkui , Ju Lei , Wang Qing , Xue Yanzhuo , Li Jiabao
Published: August 2024

In this paper, a numerical model coupling the smoothed particle hydrodynamics (SPH) with peridynamics (PD) is developed to solve the problem of the hydroelastic water entry. By combining the geometric nonlinear peridynamics with the weakly compressible SPH, the proposed model can efficiently simulate the nonlinear deformation of the structure and the deformation of a fluid free surface. The transmission of information between the fluid and solid phases is implemented by a dummy particle boundary treatment method. By simulating benchmark tests, the ability of the proposed model to solve nonlinear fluid–structure coupling problems is verified. In order to improve the computational efficiency, the graphics processing unit parallel acceleration scheme is applied to the SPH-PD model. Compared with the serial scheme, the speedup effect of the parallel scheme in large-scale computation is verified. As an application of the numerical model, the water entry of the flexible panel at a constant entry velocity is studied. The mechanism of hydroelastic effect is explained by analyzing the variations in the fluid pressure field, slamming force, and panel deformation during water entry. In addition, the influences of plate rigidity, impact velocity, and deadrise angle on the hydroelastic effect are investigated.
Simulation observation of high effectiveness laser plasma wakefield accelerator using plasma telescope configuration
Authors: Zeng Ming
Published: August 2024

In the laser wakefield accelerators, the energy transfer efficiency from the laser to the electron beam and the energy spread of the electron beam are parameters of contradiction, which people have not been able to improve simultaneously for a long time. To generate quasi-monoenergetic electron beams, the energy transfer efficiencies are up to the 1% level, while for 10% or higher energy transfer efficiencies, the electron spectra are broad in general. In the series of particle-in-cell simulations shown in this paper, we observe the simultaneous improvement of these two parameters by the self-injection mechanism in uniform plasma using the plasma telescope configuration [Zeng et al., Phys. Plasmas 27, 023109 (2020)]. The energy transfer efficiency is increased to more than 10%, and the energy spread of the electron beam is less than 5%. We also show the possibility to produce an electron beam with the energy of 1.871 GeV, the charge of 2.13 nC, and the energy spread of 2.5% by a 30 J laser.
An infinite–rank Lie algebra associated to SL(2,R) and SL(2,R)/U(1)
Authors: Campoamor-Stursberg Rutwig , Marrani Alessio , Rausch de Traubenberg Michel
Published: August 2024

We construct a generalised notion of Kac-Moody algebras using smooth maps from the non-compact manifolds M= SL(2,R) and M= SL(2,R)/U(1) to a finite-dimensional simple Lie group G. This construction is achieved through two equivalent ways: by means of the Plancherel Theorem and by identifying a Hilbert basis within L2(M). We analyze the existence of central extensions and identify those in duality with Hermitean operators on M. By inspecting the Clebsch–Gordan coefficients of sl(2,R), we derive the Lie brackets characterising the corresponding generalised Kac-Moody algebras. The root structure of these algebras is identified, and it is shown that an infinite number of simultaneously commuting operators can be defined. Furthermore, we briefly touch upon applications of these algebras within the realm of supergravity, particularly in scenarios where the scalar fields coordinatize the non-compact manifold SL(2,R)/U(1).
Research on dynamic characteristics of interior ballistics process engraving based on the coupling method
Authors: Cui Xiaoting , Huang Yong , Wang Hao
Published: August 2024

Study of the engraving process is significant for interior ballistics. Due to the high transient and strong nonlinear characteristics of the engraving, research on the engraving mechanism is challenging. In this paper, based on the one-dimensional two-phase flow model of interior ballistics coupled with explicit dynamics software, finite element simulation of the engraving is carried out to obtain the changes of parameters during the engraving process, and the dynamic characteristics of the projectile engraving are discussed. By comparing the simulation results with the experimental data, the accuracy of the coupling method in this paper is verified. The relationship between the structural parameters of the sealing band and the extrusion resistance is revealed, and the influence of the extrusion resistance on the dynamic characteristics of the projectile is demonstrated. The simulation results can provide an essential reference for selecting a reasonable sealing band structure.
Study of turbulence intermittency in unstable atmospheric surface layer and its effect on saltation sand motion based on wavelet transform
Authors: Mei Ao , Liao Yongan , Zhou Shanlin , Leng Tingting , Li Mingyang , Ma Yinhua , Zhou Lei , Xiu Chenxi
Published: August 2024

Turbulence in the atmospheric surface layer, especially in deserts and semi-arid regions, significantly affects sand movement. In unstable stratification, turbulence exhibits complex intermittency, complicating its impact on saltation. This study uses wavelet transform analysis to examine the effects of turbulence intermittency in unstable stratification on saltation. Our analysis reveals that in unstable stratification, the energy distribution of turbulence is more dispersed, the intermittent characteristics are more significant, and the intermittent burst duration of streamwise turbulence is longer, while the vertical intermittent burst duration is shorter. The fitting formulas of the energy ratio and stratification stability of the streamwise wind speed, vertical wind speed, and temperature at different frequencies are given. In addition, there is a complex nonlinear relationship between stratification stability and friction velocity on saltation. In unstable stratification, the critical wind speed required for saltation is higher than that of near-neutral, and the jumping speed and horizontal transport are weakened. Moreover, the coherence between wind speed and saltation flux increases significantly at low frequency with the increase in instability, indicating that large-scale motion plays a key role in saltation under these conditions. The more unstable the stratification is, the more obvious the phase difference fluctuation of the low frequency part is, and the more unfavorable the formation of stable saltation sand conditions. This study reveals the turbulence intermittently and its complex effects on sand particle movement in unstable stratification, which is of great significance for predicting and controlling dust storms, land desertification, and soil erosion.
Similarity solutions of a class of unsteady laminar boundary layer
Authors: Sun Bo Hua
Published: August 2024

The study of laminar unsteady boundary layer flows is essential for understanding the transition from laminar to turbulent flow, as well as the origins of turbulence. However, finding solutions to this phenomenon poses significant challenges. In this study, we introduce a novel method that employs a similarity transformation to convert the two-dimensional unsteady laminar boundary layer equations into a single partial differential equation with constant coefficients. By applying this transformation, we successfully derive similarity solutions for flat plate boundary layer flow, expressed in terms of Kummer functions. For convergent boundary layer flow, we derive an approximate analytical solution that includes both shock wave and soliton wave solutions. The superposition of these solutions provides evidence for the existence of solitons or soliton-like coherent structures (SCS) within boundary layers. Additionally, this paper explores two- and three-dimensional laminar flows, as well as three-dimensional turbulent flow equations, revealing that they all incorporate third-order derivatives with respect to spatial coordinates. This finding suggests that all viscous fluid motions have the potential to exhibit solitons/like coherent structures (SCS).
Super-radiant backward-wave oscillator with two-period slow-wave structure
Authors: Savilov Andrei
Published: August 2024

In order to significantly increase the peak power of the output wave pulse of a Cherenkov backward-wave oscillator (BWO) operating in the super-radiance regime, it is proposed to use a slow-wave structure in the form of a waveguide with a two-period corrugation. This approach is especially effective in a hybrid system in which the super-radiant wave pulse generated in a BWO with traditional single-period corrugation is amplified in a BWO with a two-period corrugation. Simulations based on the simplest 1D spatiotemporal theory predict a significant enhancement (by 4–5 times compared with the traditional super-resonant BWO version) of the peak power of the output wave pulse.
Remarkable difference in structural relaxation dynamics of conventionally prepared bulk glass and vapor-deposited thin films
Authors: Málek Jiri , Svoboda Roman
Published: August 2024

The structural relaxation dynamics of conventionally prepared bulk glass of N,N′-bis(3-methylphenyl)-N,N′-diphenyl-benzidine (TPD) was measured by differential scanning calorimetry. The calorimetric data were quantitatively described in terms of the Tool–Narayanaswamy–Moynihan (TNM) model. The TNM parameters were evaluated using a combination of linearization and non-linear optimization methodologies: h*/R = 109.5 kK, ln(A/s) = −321, β = 0.37, x = 0.64. In addition, the TNM phenomenology was used to describe recently reported normalized thickness data of stable and aged thin TPD films measured by ellipsometry. The structural relaxation was found to proceed at a markedly higher rate in these thin films prepared by the physical vapor deposition compared to that of conventional bulk glass. This feature appears to be associated with the significantly narrower distribution of relaxation times (β ≅ 0.8) observed for stable thin film in “as-deposited” form with uniquely dense molecular packing. Interestingly, very similar attributes of the relaxation kinetics were also found in the aged thin film with a previously erased thermal history associated with the deposition.
First insights into the vertical habitat use of young porbeagles in the north-western Atlantic with implications for bycatch reduction strategies
Authors: Anderson Brooke N. , Bowlby Heather D. , Saul Steven , Kang Yun , Hammerschlag Neil , Natanson Lisa J. , Sulikowski James A.
Published: August 2024

Context For threatened marine species, data on their vertical habitat use patterns can reveal risk of interactions with fishing gear and can inform bycatch avoidance strategies. Such data are lacking for young porbeagles (Lamna nasus), which are captured as bycatch in north-western Atlantic fisheries. Aims We aimed to examine temporal patterns in diving and characterise vertical habitat use of young porbeagles during summer and autumn. Methods We used data from short-term (28-day), high-resolution (5-min interval) pop-off satellite tags attached to 14 young (young-of-the-year and 1-year-old) porbeagles to model depth use. Key results Occupied depths ranged from the sea surface to 679 m, with ambient water temperatures of −0.2 to 26°C. Diel period and season were factors related to depth use. Conclusions Sharks exhibited a diel activity pattern characterised by more extensive use of the water column during the day while remaining primarily at the surface at night. Depth use differed between seasons, with summer characterised by greater affinity for surface waters (0–10 m) compared to autumn. Implications Young porbeagles are at risk of interaction with active fisheries on the continental shelf, but interactions may be reduced by setting gear deeper at night or during summer.
The revelry of plastic! Quali-quantitative variation of microplastics in freshwater before and after Carnival in south-eastern Brazil
Authors: da Costa Igor David , de Freitas Queiroz Eduardo , Nunes Natalia Neto dos Santos , Costa Leonardo Lopes , Zalmon Ilana Rosental
Published: August 2024

Context Pollution by synthetic polymers is even more problematic to the environment when this material is fragmented into small portions, forming microplastics (MPs). Aims We analysed the influence of the Brazilian Carnival on the abundance and richness of MPs in the Paraíba do Sul River (PSR). Specific objectives included classifying MPs by shape, colour and polymer, and quantifying and comparing the abundance and richness of surface-water MPs before, during and after Carnival. Methods Samples were taken from the superficial layer of the water column in 2023, by using manta net. Key results In total, 843 MPs were identified in the surface water of PSR. Higher MP concentrations were observed after the Carnival event than in the other two periods. Blue and black fibres were the predominant MPs. Glitter and sequin occurred only during the Carnival and post-Carnival periods. Polyester, polyamide and polyethylene were the most abundant in all the periods. Conclusions Our findings strongly indicated that Carnival represents a potential short-term source of MP introduction into the PSR basin. Implications A significant 170% increase in MP abundance was observed 10 days after the Carnival, which is an event occurring across multiple locations in the PSR basin.
Fluorinated macromolecular amphiphiles as prototypic molecular drones
Authors: Zheng Yujie , Zhu Lijun , Ke Changsheng , Li Yu , Zhou Zhiwen , Jiang Mou , Wang Fang , He Pei , Zhou Xin , Jiang Zhong-Xing , Chen Shizhen
Published: August 2024

The advent of drones has revolutionized various aspects of our lives, and in the realm of biological systems, molecular drones hold immense promise as “magic bullets” for major diseases. Herein, we introduce a unique class of fluorinated macromolecular amphiphiles, designed in the shape of jellyfish, serving as exemplary molecular drones for fluorine-19 MRI (
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F MRI) and fluorescence imaging (FLI)-guided drug delivery, status reporting, and targeted cancer therapy. Functioning akin to their mechanical counterparts, these biocompatible molecular drones autonomously assemble with hydrophobic drugs to form uniform nanoparticles, facilitating efficient drug delivery into cells. The status of drug delivery can be tracked through aggregation-induced emission (AIE) of FLI and
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F MRI. Furthermore, when loaded with a heptamethine cyanine fluorescent dye IR-780, these molecular drones enable near-infrared (NIR) FL detection of tumors and precise delivery of the photosensitizer. Similarly, when loaded with doxorubicin (DOX), they enable targeted chemotherapy with fluorescence resonance energy transfer (FRET) FL for real-time status updates, resulting in enhanced therapeutic efficacy. Compared to conventional drug delivery systems, molecular drones stand out for their simplicity, precise structure, versatility, and ability to provide instantaneous status updates. This study presents prototype molecular drones capable of executing fundamental drone functions, laying the groundwork for the development of more sophisticated molecular machines with significant biomedical implications.
Localized and delocalized topological modes of heat
Authors: Li Jiaxin , Xu Chengxin , Xu Zifu , Xu Guoqiang , Yang Shuihua , Liu Kaipeng , Chen Jianfeng , Li Tianlong , Qiu Cheng-Wei
Published: August 2024

The topological physics has sparked intensive investigations into topological lattices in photonic, acoustic, and mechanical systems, powering counterintuitive effects otherwise inaccessible with usual settings. Following the success of these endeavors in classical wave dynamics, there has been a growing interest in establishing their topological counterparts in diffusion. Here, we propose an additional real-space dimension in diffusion, and the system eigenvalues are transformed from “imaginary” to “real.” By judiciously tailoring the effective Hamiltonian with coupling networks, localized and delocalized topological modes are realized in heat transfer. Simulations and experiments in active thermal lattices validate the effectiveness of the proposed theoretical strategy. This approach can be applied to establish various topological lattices in diffusion systems, offering insights into engineering topologically protected edge states in dynamic diffusive scenarios.
The Frequency-Grammar Interface
Authors: Rastelli Stefano
Published: August 2024

Speakers and learners, based on memory and experience, implicitly know that certain language elements naturally pair together. However, they also understand, through abstract and frequency-independent categories, why some combinations are possible and others are not. The frequency-grammar interface (FGI) bridges these two types of information in human cognition. Due to this interface, the sediment of statistical calculations over the order, distribution, and associations of items (the regularities) and the computation over the abstract principles that allow these items to join together (the rules) are brought together in a speaker’s competence, feeding into one another and eventually becoming superposed. In this volume, it is argued that a specific subset of both first and second language grammar (termed ‘combinatorial grammar’) is both innate and learned. While not derived from language usage, combinatorial grammar is continuously recalibrated by usage throughout a speaker’s life. In the domain of combinatorial grammar, both generative and usage-based theories are correct, each shedding light on just one component of the two that are necessary for any language to function: rules and regularities.
Acknowledging dispossession
Authors: Martin J. R. , Cruz Priscilla Angela T.
Published: August 2024

This paper illustrates what can be revealed by a linguistic analysis of the discourse strategies deployed in a
bilingual text acknowledging the dispossession of Indigenous peoples in Mindanao (Philippines). The analysis draws on systemic
functional linguistics (SFL) descriptions of English, which model language as a resource for making meaning. It explores the
choices involved from the perspective of critical discourse analysis (CDA), exposing language in the service of power, and
positive discourse analysis (PDA), appreciating language as an instrument of social change. In doing so we exemplify the role of
SFL-informed CDA/PDA in processes of reconciliation, including personal and public acknowledgements and apologies, alongside
considerations of “making peace” with dispossessed Indigenous people through existing, renovated or emerging genres.
Feeling, thinking, acting
Authors: Fryer Daniel Lees
Published: August 2024

This article considers the multi- and intersemiotic expression of empathy and compassion in a campaign organised
by the Vegan Society. It draws upon insights from ecofeminism and the ethics of care as well as systemic functional semiotics as a
way of exploring how instances of attitude (affect, judgment and appreciation) in the campaign’s various texts might be negotiated
and shared, creating potentials for empathetic and compassionate responses. The study finds that parts of the campaign
represent empathy and compassion as exemplars for readers to follow, while other parts of the campaign,
especially social media, provide readers with an opportunity to enact empathy and compassion. The study also
identifies gendered and generational dimensions, and suggests that syndromes or clusters of positive and negative attitude can
form the basis for empathetic and compassionate responses.
Empathic listening as a social semiotic practice within the tradition of Nonviolent Communication
Authors: Thomson Elizabeth A.
Published: August 2024

This article investigates empathic listening as practised in the tradition of Nonviolent Communication (NVC),
noting that this tradition is understood as a designed register of interpersonal connection, “concerned with
progress toward a better world” (Hughes 2018). In the tradition,
empathy is considered “a respectful understanding of what others are experiencing, … we give to others the
time and space they need to express themselves fully and to be understood” (Rosenberg
2015: 91–92). The analysis in this article applies the tools of systemic functional linguistics to demonstrate that
this empathic understanding is achieved by the empathiser supporting the speaker’s exploration of their emotions via a linguistic
pattern of co-created, continuous thematic progression of resonated new information. The article
provides insights into the linguistic machinery powering NVC empathy practice.
From empathy to activism
Authors: Dreyfus Shoshana , Han Joshua
Published: August 2024

This paper examines how an adult’s letter to the New South Wales Minister for Disability regarding problems
identified within the disability service sector resulted in successful outcomes: that is, the changes asked for were delivered. A
range of discourse semantic tools of analysis including appraisal (Martin and White
2005) and connexion (Martin 1992; Rose
and Martin 2012) were employed in analysing this letter, which can be seen as an example of empathy activism. The
analysis identifies how the complex layering of stages and phases that organise the arguments in this letter powerfully drives the
point home, which is to convince the Minister to increase the staff ratio at a government-run respite house for children with
intellectual disabilities.
The place of feelings
Authors: Ortu Claudia
Published: August 2024

This article describes the semiotic resources deployed during the creation, in 2021, of the Alphabet Workers Union
(AWU): the trade union that represents the workforce of the tech giant Alphabet Inc. The focus is on how the union shapes and
develops its identity as one of “empathetic workers who believe in social justice” (Alphabet
Workers Union 2021). The analysis of the homepage of AWU’s website through the prism of the textual metafunction in the
visual mode (Kress and van Leeuwen 2001, 2006, 2020) together with the analysis of the interpersonal metafunction in the verbal mode according to the “appraisal”
paradigm (Martin and White 2005), shows how the union assigns a central position to
positive feelings of togetherness.