bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing the efficiency of coagulation of fine particles in cross ultrasonic fields
Authors: Tsyganok Sergey N. , Nesterov Viktor A. , Shalunov Andrey V. , Khmelev Vladimir N.
Published: February 2025

The article is devoted to the study of the process of particle agglomeration in cross ultrasonic fields. It has been established that to achieve high efficiency of particle agglomeration, it is most effective to carry out comprehensive ultrasonic exposure using a tubular emitter and two longitudinally oscillating emitters installed at the ends. At the same time, to control the structure of the generated acoustic field and change the centers of coagulation of particles, it is proposed to carry out periodic exposure to a tubular emitter in two modes of vibration (bending-radial and radial). To retain particles during switching of oscillation modes, ultrasonic exposure is carried out with a longitudinally oscillating emitter. This ensures a degree of coarsening of 15 at a concentration of 1.8 g/m3.
Installation for sorting chips and particles of coniferous wood materials in an electrostatic field by resin content
Authors: Makarov Vladimir
Published: February 2025

The article examines issues of rational use of natural resources in relation to the forest industry – stump wood, slabs, branches, tree tops. Particular attention is paid to the issue of processing low-quality wood into chips in rosin and turpentine production, where sorting chips and particles of wood materials by resin content plays an important role at the production stage. A method for sorting chips and particles of wood materials by resin content in an electrostatic field is considered. When reviewing existing designs, their shortcomings were identified, the main ones being the low efficiency of the wood separation process and high electric field strength. The author proposed a new design of a sorting device for technological chips in order to increase the efficiency of separating wood particles in an electrostatic field by resin content. A distinctive feature of this design is that the materials are charged on the conveyor when they are fed into the electrostatic field of the separator. The proposed design of the sorting device allows to increase the efficiency of the wood particle separation process and reduce the electric field intensity. An experimental setup has been created and initial studies have been conducted.
Innovative Islamic banking approaches to develop clean energy projects
Authors: Habes Almajali Ahmad
Published: February 2025

The article is devoted to innovative approaches of Islamic banking in supporting and financing clean energy projects. In the context of global challenges related to climate change and the need to transition to sustainable energy sources, Islamic banking is an important tool for the implementation of environmentally friendly and cost-effective projects. Islamic financial principles, such as the prohibition of interest, uncertainty and gambling, provide a special financing model that can be effectively applied to the implementation of renewable energy projects. Key Islamic financial instruments, such as ijara, mudaraba and mursala, provide opportunities for sustainable investments in solar, wind and hydropower projects, as well as other environmentally friendly technologies. The article structures examples of successful application of Islamic financial instruments in the clean energy sector, analyzes the potential benefits and challenges faced by Islamic financial institutions when investing in environmental projects. The main findings highlight the need for further development of Islamic banking to support the global transition to sustainable energy sources, as well as the role of Islamic finance in combating climate change and ensuring a sustainable energy future for all countries.
Using blockchain and digital marketing to build trust in green projects
Authors: Ali Al-Ababneh Hassan , Ahmad Alkhudierat Noor , Mohd Salim Barhoush Fawaz , Habes Almajali Ahmad , Ibragimkhalilova Tatyana , Ibrahim Mugableh Mohamed
Published: February 2025

The article is devoted to the study of the application of blockchain technologies and digital marketing to increase trust in green projects focused on sustainable development and environmentally friendly technologies. In the context of modern information overload and a high degree of consumer mistrust of environmental initiatives, it is important to use innovative tools that will ensure transparency, security and reliability of information. Blockchain as a distribution database allows us to guarantee the immutability of data on the origin of products and production processes, which is especially important in the field of green technologies, where there is often a risk of “greenwashing” - falsification of environmental characteristics of products. In turn, digital marketing using tools such as social networks, SEO and content marketing helps to effectively convey information about green initiatives to the target audience and create trust. The article analyzes existing methods and successful examples of blockchain implementation in the marketing strategies of companies operating in the field of renewable energy and sustainable production. The prospects and challenges of implementing these technologies, as well as their synergy for creating transparent and trusting relationships between companies and consumers are also considered.
AI-driven orchard management: Advancing sustainable apple production through convolutional neural network recognition
Authors: Karabanov Georgy , Ricardo Oke Olouafemi , Krakhmalev Alexey
Published: February 2025

The aim of this study is to develop a convolutional neural network architecture designed for apple recognition in images. The relevance of this task is tied to the need for fruit recognition to automate the process of apple crop harvesting. To reduce computations, it is proposed to convert the image captured by the camera from RGB format to HSV format. Using the example of a red apple, the creation of a bitmask is demonstrated, which allows for the identification of regions of the desired color within the image. A structure and parameters of the convolutional neural network were proposed, along with a method for computing the distance between the detected object and the camera based on the pre-calculation of the focal length. To analyze the results of the neural network under consideration, software was developed in Python using the TensorFlow and Keras libraries. The training and testing of the neural network were conducted on a PC Aspire A315-23 with an AMD Athlon Silver 3050U 1.2 GHz processor, 4 GB DDR4 RAM, and an AMD Radeon Graphics 2.30 GHz graphics card, running Windows 11 Pro operating system. The neural network was trained for 15 epochs, taking 217 seconds in total. Object recognition by the trained neural network took around 1 second. The proposed convolutional neural network model demonstrated a recognition accuracy of 86% on the test image set.
Sensorineural Hearing Loss after Chemoradiotherapy with High-Dose Cisplatin in Patients with Head and Neck Cancer
Authors: Kitoh Ryosuke , Hirose Kota , Kasuga Mariko , Hori Kentaro , Yokota Yoh , Iwasa Yoh-ichiro , Takumi Yutaka
Published: February 2025

Objective To investigate sensorineural hearing loss in patients with head and neck cancer receiving chemoradiotherapy (CRT) with a standard regimen of high-dose cisplatin, focusing on the acute changes before and after CRT with high-dose cisplatin (CDDP).

Materials and Methods A total of, 135 cases of head and neck cancer treated with high-dose cisplatin-based CRT between 2014 and 2023 were included in this retrospective study. The hearing threshold shifts at each frequency before and after each CDDP dose were used as an indicator to assess hearing impairment.

Results The CRT-induced hearing threshold shift was greater at frequencies >4,000 Hz, with a threshold increment of ∼10 dB at 4,000 Hz and 20 dB at 8,000 Hz. The threshold after each course of CDDP was elevated at one week after CDDP administration, and the changes in the thresholds from one week after administration to just before the subsequent course were small. Total CDDP dose, radiation dose to the cochlea, and mean pretreatment hearing thresholds were identified as significant factors influencing the increase in hearing thresholds at 8,000 Hz.

Conclusion In patients with head and neck cancer receiving CRT with high-dose cisplatin, threshold increment was predominantly observed at frequencies >4,000 Hz, as previously reported. The threshold increment occurred immediately after CDDP administration, which might be relevant when considering the timing of future interventions.
The embodied, entangled self and complicity in the neoliberal academy
Authors: Barthwal-Datta Monika
Published: February 2025

In The Self, and Other Stories: Being, Knowing, Writing, Laura Shepherd illuminates the embodied and entangled nature of knowing the self, and the self as a ‘knowing subject’ in the neoliberal, violent, and exclusionary academy. Here, I explore some of the ways in which such embodiment and entanglements of the self in the academy are made (in)visible in and through the stories and storytelling in Laura’s book. I focus particularly on Laura’s recounting of her complicity with the institution, for instance through her internalization of the individualized responsibility for ‘success’ in the neoliberal academy towards hyper-productivity, and her embodying and enacting of the ‘serious’ ‘knowing’ subject in academia. Noting the significance of such stories for the demystification of ‘success’ as an academic, and the cost such success may extract from the self, I consider how there is still room left to reflect on the implications of such complicity by relatively privileged bodies, for those bodies positioned differently and differentially in the neoliberal university.
Joule-heated absorbent “sponge” cleans up crude oil spills
Authors: Thompson Avery
Published: February 2025

Cheap, efficient material rapidly separates oil from water, facilitating cleanup of environmental disasters.
Transient temperature measurement of electron beam bombarded stainless steel via nanosecond two-color pyrometry
Authors: Watson T. M. , Mockert J. T. , Neuber A. A. , Dickens J. C.
Published: February 2025

A two-color pyrometer is presented that enables detection of a temperature rise with temporal resolution of 17.5 ns. It is geared toward extreme environments where fast electrical electron pulses or currents may push the temperature of a metal surface to melt on a 100 ns time scale. The developed pyrometer, which utilizes an internal gain of 100x, has been tested for SS304 surfaces subjected to an intense electron beam in vacuum. The two-color pyrometer is calibrated using a quasi-calibration method by heating a graphite disk and measuring this temperature with a FLIR TG297 thermal camera. The quasi-calibration method supports the pyrometer to be within 3% accuracy of absolute temperature. The measured temporal temperature profile of the SS304 surface was derived from the pyrometer output data through a detailed gray-body analysis utilizing empirical emissivity data from publicly available literature.
High-power and narrow-linewidth laser on thin-film lithium niobate enabled by photonic wire bonding
Authors: Franken Cornelis A. A. , Cheng Rebecca , Powell Keith , Kyriazidis Georgios , Rosborough Victoria , Musolf Juergen , Shah Maximilian , Barton David R. , Hills Gage , Johansson Leif , Boller Klaus-J. , Lončar Marko
Published: February 2025

Thin-film lithium niobate (TFLN) has emerged as a promising platform for the realization of high-performance chip-scale optical systems, spanning a range of applications from optical communications to microwave photonics. Such applications rely on the integration of multiple components onto a single platform. However, while many of these components have already been demonstrated on the TFLN platform, to date, a major bottleneck of the platform is the existence of a tunable, high-power, and narrow-linewidth on-chip laser. Here, we address this problem using photonic wire bonding to integrate optical amplifiers with a TFLN feedback circuit. We demonstrate an extended cavity diode laser with an excellent side mode suppression ratio exceeding 60 dB and a wide wavelength tunability over 43 nm. At higher currents, the laser produces a high maximum on-chip power of 76.2 mW while maintaining 51 dB side mode suppression. The laser frequency stability over short timescales shows an ultra-narrow intrinsic linewidth of 550 Hz. Long-term recordings indicate a high passive stability of the photonic wire bonded laser with 58 hours of mode-hop-free operation, with a trend in the frequency drift of only 4.4 MHz/h. This work verifies photonic wire bonding as a viable integration solution for high performance on-chip lasers, opening the path to system level upscaling and Watt-level output powers.
Dark-field x-ray microscopy for 2D and 3D imaging of microstructural dynamics at the European x-ray free-electron laser
Authors: Irvine Sara J. , Katagiri Kento , Ræder Trygve M. , Boesenberg Ulrike , Chalise Darshan , Stanton Jade I. , Pal Dayeeta , Hallmann Jörg , Ansaldi Gabriele , Brauße Felix , Eggert Jon H. , Fang Lichao , Folsom Eric , Haubro Morten , Holstad Theodor S. , Madsen Anders , Möller Johannes , Nielsen Martin M. , Poulsen Henning F. , Pudell Jan-Etienne , Rodriguez-Fernandez Angel , Schoofs Frank , Seiboth Frank , Wang Yifan , Jo Wonhyuk , Youssef Mohamed , Zozulya Alexey , Haldrup Kristoffer , Dresselhaus-Marais Leora E.
Published: February 2025

Dark field x-ray microscopy (DXFM) can visualize microstructural distortions in bulk crystals. Using the femtosecond x-ray pulses generated by x-ray free-electron lasers (XFELs), DFXM can achieve sub-μm spatial resolution and <100 fs time resolution simultaneously. In this paper, we demonstrate ultrafast DFXM measurements at the European XFEL to visualize an optically driven longitudinal strain wave propagating through a diamond single crystal. We also present two DFXM scanning modalities that are new to the XFEL sources: spatial 3D and 2D axial-strain scans with sub-μm spatial resolution. With this progress in XFEL-based DFXM, we discuss new opportunities to study multi-timescale spatiotemporal dynamics of microstructures.
Ultrafast optical and passive acoustic mapping characterization of nanoscale cavitation nuclei based on gas vesicle proteins
Authors: Smith Cameron A. B. , Bar-Zion Avinoam , Wu Qiang , Malounda Dina , Bau Luca , Stride Eleanor , Shapiro Mikhail G. , Coussios Constantin C.
Published: February 2025

Genetically encodable gas-filled particles, known as gas vesicles (GVs), have shown promise as a biomolecular contrast agent for ultrasound imaging and have the potential to be used as cavitation nuclei for ultrasound therapy. In this study, we used passive acoustic mapping techniques to characterize GV-seeded cavitation, utilizing 0.5 and 1.6 MHz ultrasound insonation over peak rarefactional pressures ranging from 100 to 2200 kPa. We found that GVs produce cavitation for the duration of the first applied pulse, up to at least 5000 cycles, but that bubble activity diminishes rapidly over subsequent pulses. At 0.5 MHz, the frequency content of cavitation emissions was predominantly broadband in nature, while at 1.6 MHz, narrowband content at harmonics of the main excitation frequency dominated. Simulations and high-speed camera imaging suggest that the received cavitation emissions come not from individual GVs but instead from the coalescence of GV-released gas into larger bubbles during the applied ultrasound pulse. These results will aid the future development of GVs as cavitation nuclei in ultrasound therapy.
Study on the mechanisms of anode plasma generation and ion acceleration in low-current pulsed vacuum arc discharge
Authors: Song Mengmeng , Liu Zhaohui , Dong Ye , Sun Qiang , Wang Ziming , Zhang Hantian , Wu Wenbin , Yang Wei , Zhou Qianhong
Published: February 2025

Anodic vacuum arc ion sources find wide applications in electric propulsion and thin-film deposition systems, but the poor understanding of the generation and acceleration mechanisms of anode plasma imposes confinement on improving the performance of these devices. In this paper, the discharge process of low-current pulsed vacuum arc is self-consistently tracked using a 1D spherical particle-in-cell direct simulation Monte Carlo method coupled with an anode heat conduction model. The results show that in the vacuum spark stage, the electrons emitted from cathode spot can gain enough energy from the high pulsed voltage to heat anode to evaporate atoms and then generating anode plasma. The anode ions move toward the cathode under the electric field formed by high anode voltage, with kinetic energy being up to about hundreds of eV. As the discharge gradually transitions to arc stage, the low arc voltage reduces electrons heating on anode, and anode atoms are sputtered by cathode ions to sustain an anode arc. During the arc stage, the potential establishes a bimodal hump distribution. The newly generated anode ions are accelerated by anode potential hump and its pressure gradient to ∼103 m/s, which is one order of magnitude lower than that of cathode ions. These findings could be valuable in optimizing the design of an anodic arc ions source for efficiency improvement.
A perspective on soft matter molecular simulations: Deformation and flow at mesoscopic timescales
Authors: Tung Chi-Huan , Cheung Kin , Fan Yue , Kushima Akihiro , So Kang Pyo , Chen Wei-Ren , Yip Sidney
Published: February 2025

In Multiscale Materials Modeling, an enduring vision is to extract the molecular mechanisms governing a certain materials phenomenon of interest in order to predict how the phenomenon will behave at a later time. This goal of predictive simulation has been discussed about a decade ago as a materials research challenge, in the Mesoscale Science Frontier, MSS. To date, it continues to motivate a growing community of computational materials science and technology. Here, we consider several materials phenomena of interest, each well known in their specific areas of application, to note that while molecular dynamics simulation is arguably the most widely used method, MD results have limitations in predicting or explaining the behavior of the phenomenon. For the type of phenomena selected here, we believe that one can raise the issue of whether MD is an appropriate method of molecular simulation in the design and performance testing of complex materials. There exists an alternative to MD, the approach of meta-dynamics simulation based on energy landscape sampling and transition state theory. This approach is notable because it allows predictive molecular simulations over timescales considerably longer than the traditional MD. We are in the process of implementing an enhanced meta-dynamics approach aimed at identifying unknown defect mechanisms, making it particularly well-suited for investigating the deformation processes in engineering alloys at timescales relevant to laboratory measurements of component performance and durability assurance. Our motivation is that such simulation capabilities will find many materials-centric applications. One such application is known as plasma-materials interactions, PMI. In PMI, the phenomenon of nuclear irradiation damage has been a practical challenge, relevant to both nuclear fission and fusion power generation systems. For the present perspective, we will focus on the use of meta-dynamics simulations in collaboration with the research activities at an academic fusion research center.
Collective excitations in active solids featuring alignment interactions
Authors: Kinoshita Yutaka , Uchida Nariya , Menzel Andreas M.
Published: February 2025

With increasing emphasis on the study of active solids, the features of these classes of nonequilibrium systems and materials beyond their mere existence shift into focus. One concept of active solids addresses them as active, self-propelled units that are elastically linked to each other. The emergence of orientationally ordered, collectively moving states in such systems has been demonstrated. We here analyze the excitability of such collectively moving elastic states. To this end, we determine corresponding fluctuation spectra. They indicate that collectively excitable modes exist in the migrating solid. Differences arise when compared to those of corresponding passive solids. We provide evidence that the modes of excitation associated with the intrinsic fluctuations are related to corresponding modes of entropy production. Overall, by our investigation, we hope to stimulate future experimental studies that focus on excitations in active solids.
The interplay of heterogeneity and product detachment in templated polymer copying
Authors: Guntoro Jeremy E. B. , Qureshi Benjamin J. , Ouldridge Thomas E.
Published: February 2025

Templated copolymerization, in which information stored in the sequence of a heteropolymer template is copied into another polymer product, is the mechanism behind all known methods of genetic information transfer. A key aspect of templated copolymerization is the eventual detachment of the product from the template. A second key feature of natural biochemical systems is that the template-binding free energies of both correctly matched and incorrect monomers are heterogeneous. Previous work has considered the thermodynamic consequences of detachment and the consequences of heterogeneity for polymerization speed and accuracy, but the interplay of both separation and heterogeneity remains unexplored. In this work, we investigate a minimal model of templated copying that simultaneously incorporates both detachment from behind the leading edge of the growing copy and heterogeneous interactions. We first extend existing coarse-graining methods for models of polymerization to allow for heterogeneous interactions. We then show that heterogeneous copying systems with explicit detachment do not exhibit the subdiffusive behavior observed in the absence of detachment when near equilibrium. Next, we show that heterogeneity in correct monomer interactions tends to result in slower, less accurate copying, while heterogeneity in incorrect monomer interactions tends to result in faster, more accurate copying, due to an increased roughness in the free energy landscape of either correct or incorrect monomer pairs. Finally, we show that heterogeneity can improve on known thermodynamic efficiencies of homogeneous copying, but these increased thermodynamic efficiencies do not always translate to increased efficiencies of information transfer.
Stimulated Brillouin scattering in a non-suspended ultra-low-loss thick-SOI platform
Authors: Ye Kaixuan , Keloth Akshay , Marin Yisbel E. , Cherchi Matteo , Aalto Timo , Marpaung David
Published: February 2025

Silicon photonics, with its CMOS compatibility and high integration density, has enabled a wide range of novel applications. Harnessing stimulated Brillouin scattering (SBS), an optomechanic interaction between optical and gigahertz acoustic waves, in silicon-on-insulator (SOI) platforms attracts great interest for its potential in narrow-linewidth lasers and microwave photonics. However, the poor optoacoustic overlap in silicon nanowires on conventional SOI platforms has previously restricted the observation of SBS signals to suspended silicon waveguide structures. In this work, we report, for the first time, the SBS response in a non-suspended ultra-low-loss thick-SOI waveguide platform. The backward SBS process in this 3 μm thick SOI platform is enabled by a leaky acoustic mode that coexists with the optical mode in the waveguide core, resulting in an enhanced optoacoustic overlap. We measured Brillouin gain coefficients of 2.5 and 1.9 m−1 W−1 at 37.6 GHz for the rib and strip waveguides, respectively. This work paves the way for Brillouin-based applications in non-suspended ultra-low-loss silicon photonics systems.
Deep learning-based real-time prediction of coronary artery blood flow pressure from computed tomography angiography
Authors: Yang Yang , Li Bao , Wen Chuanqi , Fan Luyao , Li Tengfei , Feng Yili , Wang Tongna , Sun Hao , Liu Na , Zhang Liyuan , Liu Jian , Wang Lihua , Liu Youjun
Published: February 2025

The deep learning-based high-performance computational fluid dynamics (CFD) solution method is currently a hot, frontier topic in hemodynamic research. However, accurate predictions of the flow field with different coronary geometries and boundary conditions remain challenging. Given this, this study proposes a method based on deep learning and coronary computed tomography angiography (CTA) that achieves rapid and accurate solutions for blood flow pressure. We established a dataset based on patient-specific data from 370 patients and proposed a deep learning model with dual encoding of boundary condition and geometry. The model inputs boundary conditions obtained by patient-specific physiological parameters and coronary artery geometric information achieved by coronary CTA to iteratively predict the blood flow pressure along the centerline of the coronary artery in real-time. Statistical analysis was performed to evaluate the efficacy of the method by comparing it with CFD simulations. Testing on 112 cases, the root mean square error (RMSE) was 4.34% compared to the blood flow pressure obtained by CFD simulations. The computational efficiency of predictions using the trained deep learning model has improved by 180 times compared to CFD simulations (10 s VS 0.5 h). The proposed method in this study can provide accurate, real-time predictions of blood flow pressure for different coronary geometries and boundary conditions, which significantly improves computational efficiency and reduces costs while maintaining a high level of calculation accuracy.
Multi-mode vortex-induced vibrations characteristics based on a full bridge aeroelastic model
Authors: Wang Zhen , Zhu Jinsong , Wen Changcheng , Zhang Zhitian
Published: February 2025

An increasing number of real bridges experience multi-modal vortex-induced vibrations (VIVs). In this paper, the multi-modal VIV characteristics of flexible suspension bridges are investigated based on a full-bridge aeroelastic model in a wind tunnel. First, the generalized free decay method is employed to determine equivalent linear damping ratios and amplitude-dependent damping ratios. It is found that the higher order structural and aerodynamic damping ratio exhibit a significant nonlinearity increase as the amplitude increases. The time-frequency-energy spectrum method is used to capture the mode-switching/competition phenomenon, and it is analyzed quantitatively in terms of modal weight ratios and energy transfer. The results indicate that the multi-modal VIV amplitude is not only related to the Scruton number (Sc) and mode shapes but also directly associated with the modal weights and energy ratio. Other things being equal, higher modal weight ratios and concentrated energy lead to larger amplitudes. In addition, mode competition occurs mainly during mode switching, and its competitiveness is related to the damping ratio. The main features are as follows: in temporal and spatial terms, the response exhibits a quasi-stable periodic beating motion characterized by significant nonlinear effects; in the frequency domain, there is a common check and balance of two or three adjacent frequencies, with the modal weight ratios alternately dominating; and in terms of energy, mode-to-mode energy is transferred and balanced dynamically, which can lead to a decrease in the VIV amplitude during the transition.
Switchable nanochannel flow control through weak polyelectrolyte brushes
Authors: Yuan Jiaxing , Tanaka Hajime
Published: February 2025

Surface modification of nanochannels with polyelectrolyte brushes (PEBs) offers a powerful mechanism for controlling nanoscale flow transport. In aqueous environments, weak polyelectrolytes (PEs) possess ionizable groups whose charges are influenced not only by pH and salt concentration but also by the conformations of PEBs and solvent flow. This charge-structure coupling is a key feature in nanofluidics, yet its effects on transport behavior remain poorly understood. We employ hybrid Monte Carlo/molecular dynamics simulations to model the dissociation/association of ionizable groups, combined with dissipative particle dynamics to simulate solvent flow. Our results reveal that nanochannels coated with weak PEs enable switchable control of pressure-driven flows, exhibiting an on–off transition between slow flow in a closed state and rapid flow in an open state, with the flux between the two states differing by almost one order of magnitude. Furthermore, compared to constant-charge strong PEBs, the on–off transition occurs at a lower pressure gradient for charge-regulating PEBs due to a dynamic reduction in degrees of ionization in response to brush compression under external flow fields. Our work offers novel microscopic insight into flow control within smart nanofluidic systems utilizing grafted weak PEBs and demonstrates an efficient and accurate numerical methodology to advance future studies on the non-equilibrium dynamics of pH-responsive soft materials under flow conditions.
Single cavitation bubble dynamics induced by laser-generated plasma near a biomimetic mesotextured boundary
Authors: Kadivar Ebrahim , Afshari Mohammadmahdi , el Moctar Ould
Published: February 2025

In this study, we directly monitored the collapse dynamics of a single cavitation bubble induced by laser-generated plasma near a biomimetic mesotextured boundary placed in distilled water via the shadowgraphy technique. Comparing the single cavitation bubble mechanism near a plain solid surface with the one near the biomimetic mesotextured surface allowed to investigate the effects of the biomimetic mesotextured surface on the control of the single bubble collapse dynamics at various relative wall distances. The results show that the microjet toward the plain surface during the first collapse of the bubble is manipulated when the biomimetic mesotextured surface is replaced. No substantial impact of the bubble collapse on the biomimetic boundary was observed. This results from the fact that the microjet was mitigated during the first stage of the bubble collapse. Moreover, in the second phase of the bubble collapse, no toroidal structures attached on the wall surface of the biomimetic mesotextured boundary are formed at different relative wall distances. In addition, first and second bubble collapse stages near the modified boundary happened earlier than the first and second bubble collapses near the plain surface at most relative wall distances. Furthermore, the equivalent bubble radius for the bubble near the biomimetic boundary was mitigated compared to the equivalent bubble radius for the bubble near the plain boundary at most relative wall distances.
Effect of triaxial stress on permeability and enhancement rate of coal seams: Implications for gas extraction efficiency
Authors: Jing ShiJie , Zhao HongBao , Liu Chao , Li ZuoQuan
Published: February 2025

The permeability enhancement of coal seams plays a critical role in gas extraction efficiency. The true triaxial stress changes generated during the coal mining process can cause alterations in the permeability of the coal. Experiments were conducted to investigate the deformation and permeability evolution of coal under true triaxial stress conditions, and an analytical model of stress–strain was developed to quantify the seepage behavior under true triaxial stress. To clarify the spatial distribution and evolution of permeability enhancement within coal seams under mining-induced stress, a permeability enhancement model was established. The results indicate: (1) Both anisotropic stress significantly influence coal permeability; (2) Stress unloading leads to matrix shrinkage and fracture expansion, resulting in an exponential increase in permeability with unloading; (3) Under true triaxial conditions, horizontal stress constraint has a greater impact on permeability evolution than vertical stress. (4) The coal seam can be divided into four stages: Stage I: Maximized Permeability Enhancement after Coal Failure; Stage II: Increased Permeability Enhancement with Pressure Depletion; Stage III: Decreased Permeability Enhancement with Rising Pressure; Stage IV: Stable Permeability Enhancement under Original In Situ Stress. Permeability enhancement primarily occurs during Stages II and I. Propose field construction recommendations tailored to the varying stages of coal seams to enhance gas extraction efficiency.
Joint approximate diagonalization approach to quasiparticle self-consistent GW calculations
Authors: Duchemin Ivan , Blase Xavier
Published: February 2025

We introduce an alternative route to quasiparticle self-consistent GW calculations (qsGW) on the basis of a joint approximate diagonalization of the one-body GW Green’s functions G(εnQP) taken at the input quasiparticle energies. Such an approach allows working with the full dynamical self-energy, without approximating the latter by a symmetrized static form as in the standard qsGW scheme. Calculations on the GW100 molecular test set lead, nevertheless, to a good agreement, at the 60 meV mean-absolute-error accuracy on the ionization potential, with respect to the conventional qsGW approach. We show further that constructing the density matrix from the full Green’s function as in the fully self-consistent scGW scheme, and not from the occupied quasiparticle one-body orbitals, allows obtaining a scheme intermediate between the qsGW and scGW approaches, closer to coupled-cluster reference values.
Solute dispersion in unsteady and viscous flow regimes of a non-Newtonian fluid flow with periodic body acceleration/deceleration
Authors: Pal Prem Babu , Singh Shalini , Murthy P. V. S. N.
Published: February 2025

This study seeks to analyze unsteady solute dispersion in the pulsatile flow of a non-Newtonian Ellis fluid within a tube, influenced by periodic body acceleration and deceleration, across three distinct flow and dispersion regimes: viscous flow with diffusive dispersion, viscous flow with unsteady dispersion, and unsteady flow with unsteady dispersion. These are characterized by the interplay between the values of the Péclet number Pe, the Womersley frequency parameter α, which is associated with the pressure pulsation, and the oscillatory Péclet number P which has inherently the Schmidt number Sc. The fluid velocity is computed for all α, then Aris' method of moments is employed to solve the convection–diffusion equation considering the higher order moments. Impact of the body acceleration/deceleration parameter M, wall absorption parameter β, degree of shear thinning behavior index a, shear stress τ1/2, α, and the fluctuating pressure parameter e on the mean solute concentration Cm is investigated. The value of the dispersion coefficient decreased monotonically in the viscous flow with the diffusive dispersion region, while the skewness and kurtosis both have shown significant variations in the unsteady dispersion regime, which lead to the significant variation in the axial mean concentration. Graphical analysis reveals a leftward shift and a diminished peak in the mean concentration, resulting in non-Gaussian behavior under body acceleration/deceleration conditions. As τ1/2→∞, this Ellis fluid behaves like the Newtonian fluid, these results agree with those results for Newtonian fluid flow case.
Mechanisms of hypersonic shock wave and turbulent boundary layer interaction on a cone/flare
Authors: Sun Xuecheng , Yu Changping , Li Xinliang , Zhang Chuanhong
Published: February 2025

A direct numerical simulation of a hypersonic 7°–34° cone/flare model at the Mach number Ma∞ = 6 and unit Reynolds number Re∞ = 10 800/mm is performed to investigate the shock wave/turbulent boundary layer interaction of three-dimensional configuration. To study the influence of spanwise curvature, the differences between the cone/flare configuration and the double wedge configuration are discussed. Compared to the double wedge, the height of the separation bubble of the cone/flare is lower, and the skin friction coefficient and Stanton number in both the upstream undisturbed region and the downstream reattachment region are smaller. The Görtler vortex analysis shows that the cone/flare configuration produces more Görtler vortices, but with lower intensity. The turbulent kinetic energy budget is analyzed, and the results indicate that the distribution of turbulent kinetic energy in the interaction region differs significantly from that in the upstream undisturbed region, the peak values of each term increase notably, with the influence of the turbulent transport term being significantly enhanced and the influence of the viscous dissipation term notably weakened. The spectral proper orthogonal decomposition analysis reveals that in the streamwise/wall-normal plane, the low-frequency characteristics of the flow are associated with the separation bubble and the shear layer in the reattachment region, while the high-frequency characteristics are primarily linked to turbulent fluctuations. In the streamwise/spanwise plane, the low-frequency characteristics are associated with the upstream velocity streaky structures and the large-scale alternating positive and negative streaky structures that form along the spanwise direction after the flow reattaches.
An improved sliding mode observer algorithm for PMSM based on deformable fuzzy neural network
Authors: Li Xiaolin , Liu Na , Song Juan , Zhang Yiyan
Published: February 2025

To address the issue of poor speed estimation performance caused by the inability of sensor parameters to adjust in real time under complex working conditions in traditional sliding mode observer sensorless control techniques for permanent magnet synchronous motors (PMSM), an improved sliding mode sensorless algorithm combining radial basis function (RBF) neural networks and fuzzy logic control theory is proposed. This improved algorithm accurately obtains the Jacobian matrix of the PMSM through an RBF neural network parameter identifier, and based on this, it rapidly determines the structural situation of the deformable fuzzy neural network through a variable structure learning process. Simulation results obtained from MATLAB/Simulink demonstrate that this estimation algorithm enhances the speed control accuracy of the PMSM vector control system by 5.9% when compared to the proportion integral differential (PID) speed controller algorithm and by 26.9% when compared to the sliding mode speed controller algorithm. The findings suggest that the proposed algorithm enhances the accuracy of speed estimation and rotor position while optimizing the speed control performance of vector control system.
An oil recovery factor-based method for determination on the lower limit of pore-throat for waterflooding in low-permeability reservoirs
Authors: Zheng Zigang , Fu Guotao , Zhang Yongqiang , Dai Yuting , Li Danchen , Zhan Jie , Gao Chunning , Fan Liwu
Published: February 2025

Waterflooding serves as a major secondary tight oil recovery technique due to its merits of low risk, cost-effectiveness, and easy operation. The lower limit of pore-throat is one of the most vital metrics for oil and gas resource potential and productivity evaluation. However, the existing determination methods cannot directly reflect reservoir performance during the production process. In this paper, a new method was proposed by introducing the oil recovery factor (RF) as a criterion to intuitively determine the lower limit of pore-throat for waterflooding in low-permeability reservoirs. Three tight sandstone core samples with representative permeabilities were studied. High-pressure mercury injection and nuclear magnetic resonance measurements were employed to characterize the pore-throat size distribution and the transient variation of oil–water distribution in waterflooding experiments. The lower limits of pore-throat for waterflooding of core #1 (0.128 mD), #2 (0.490 mD), and #3 (0.950 mD) were found to be 43, 46, and 46 nm, respectively. Cores with a higher permeability demonstrated lower overall RFs, which is contrary to expectations. According to the pore-throat size distribution categorized by the lower limit, this observation can be attributed to the increased proportion of unrecoverable region at higher permeabilities, suggesting that permeability, as a macro indicator, might fall short in representing the actual microstructure of flow pathways within a reservoir. Microscopic visualization of the waterflooding experiment was also conducted to intuitively observe the distribution and morphology of residual oil in both unrecoverable and recoverable regions. Our work provides a new method for accurately determining the lower limit of pore-throat from oil productivity perspective and offers data support and a guidance for effective waterflooding exploitation of tight oil reservoirs.
X-band polarization conversion radome based on dielectric-embedded metamaterial elements for high-power microwave application
Authors: Yan Feng , Yuan Chengwei , Zhuang Qinghe , Yang Meng , Yang Wensen , Xiong Zhengfeng
Published: February 2025

A novel polarization conversion radome based on dielectric-embedded metamaterial elements is proposed to decrease the size of antenna profiles. This radome is composed of two kinds of interlaced dielectric-embedded metamaterial elements to realize the polarization conversion and beam deflection. The structures and characteristics of two types of dielectric-embedded metamaterial elements have been studied and analyzed. By selecting an appropriate dielectric material and applying periodic boundary conditions to optimize these two kinds of dielectric-embedded metamaterial elements, the radome made up of these metamaterial elements eventually is mounted atop a square horn antenna. Simulation results indicate that the antenna radome enables the horn antenna to achieve polarization conversion and beam deflection at the operating frequency. The maximum beam deflection angle can be 29° within a gain reduction of 1 dB, while the axial ratio remains below 1.5 dB and the reflection coefficient continuously remains below −22 dB. Moreover, the power-handling capacity of each metamaterial element within the radome is above 60 kW.
Temperature-dependent polar lignification of a seed coat suberin layer promoting dormancy in
Arabidopsis thaliana
Authors: Hyvärinen Lena , Fuchs Christelle , Utz-Pugin Anne , Gully Kay , Megies Christian , Holbein Julia , Iwasaki Mayumi , Demonsais Lara , Capitão Maria Beatriz , Barberon Marie , Franke Rochus B. , Nawrath Christiane , Loubéry Sylvain , Lopez-Molina Luis
Published: February 2025

The seed is a landmark plant adaptation where the embryo is sheltered by a protective seed coat to facilitate dispersion. In
Arabidopsis
, the seed coat, derived from ovular integuments, plays a critical role in maintaining dormancy, ensuring germination occurs during a favorable season. Dormancy is enhanced by cold temperatures during seed development by affecting seed coat permeability through changes in apoplastic barriers. However, their localization and composition are poorly understood. This study identifies and investigates a polar barrier in the seed coat’s outer integument (oi1) cells. We present histological, biochemical, and genetic evidence showing that cold promotes polar seed coat lignification of the outer integument 1 (oi1) cells and suberization throughout the entire oi1 cell boundary. The polar oi1 barrier is regulated by the transcription factors MYB107 and MYB9. MYB107, in particular, is crucial for the lignified polar oi1 barrier formation under cold temperatures. The absence of the oi1 barrier in mutant seeds correlates with increased permeability and reduced dormancy. Our findings elucidate how temperature-induced modifications in seed coat composition regulate dormancy, highlighting the roles of suberin and lignin in this process.
The genomic and epigenomic landscapes of hemizygous genes across crops with contrasting reproductive systems
Authors: Peng Yanling , Wang Yiwen , Liu Yuting , Fang Xinyue , Cheng Lin , Long Qiming , Su Dalu , Zhang Tianhao , Shi Xiaoya , Xu Xiaodong , Xu Qi , Wang Nan , Zhang Fan , Liu Zhongjie , Xiao Hua , Yao Jin , Tian Ling , Hu Wei , Chen Songbi , Wang Haibo , Huang Sanwen , Gaut Brandon S. , Zhou Yongfeng
Published: February 2025

Hemizygous genes, which are present on only one of the two homologous chromosomes of diploid organisms, have been mainly studied in the context of sex chromosomes and sex-linked genes. However, these genes can also occur on the autosomes of diploid plants due to structural variants (SVs), such as a deletion/insertion of one allele, and this phenomenon largely unexplored in plants. Here, we investigated the genomic and epigenomic landscapes of hemizygous genes across 22 genomes with varying propagation histories: eleven clonal lineages, seven outcrossed samples, and four inbred and putatively homozygous genomes. We identified SVs leading to genic hemizygosity. As expected, very few genes (0.01 to 1.2%) were hemizygous in the homozygous genomes, representing negative controls. Hemizygosity was appreciable among outcrossed lineages, averaging 8.7% of genes, but consistently elevated for the clonal samples at 13.8% genes, likely reflecting heterozygous SV accumulation during clonal propagation. Compared to diploid genes, hemizygous genes were more often situated in centromeric than telomeric regions and experienced weaker purifying selection. They also had reduced levels of expression, averaging ~20% of the expression levels of diploid genes, violating the evolutionary model of dosage compensation. We also detected higher DNA methylation levels in hemizygous genes and transposable elements, which may contribute to their reduced expression. Finally, expression profiles showed that hemizygous genes were more specifically expressed in contexts related to fruit development, organ differentiation, and stress responses. Overall, hemizygous genes accumulate in clonally propagated lineages and display distinct genetic and epigenetic features compared to diploid genes, shedding unique insights into genetic studies and breeding programs of clonal crops.
Learner pragmatics in English-medium‑instruction courses at university
Authors: Martí Otilia , Guzmán-Alcón Irene
Published: February 2025

This paper critically reviews pragmatic-oriented investigations of English-medium instruction (EMI) courses in
tertiary education. Analyses on potential gains in pragmatic competence, classroom interaction, and e-politeness define some of
the lines of research identified. Speech acts like requests and opinions (e.g., Taguchi,
2012, 2014) or directives (e.g., Smit,
2010) are still the main foci of interest, along with pragmatic markers (e.g., Ament et al., 2018) or openings and closings (e.g., Codina-Espurz
& Salazar-Campillo, 2019). A more holistic perspective has also been adopted to examine functional adequacy in
writing (e.g., Herraiz-Martinez & Alcón-Soler, 2019). Strengths and limitations of
studies conducted in the EMI context are discussed and, from this, a research agenda is put forward. Lastly, future investigators
are encouraged to explore the complex interplay between external (e.g., target language contact) and internal factors (e.g.,
proficiency, motivation, or willingness to communicate) which may have an impact on learner pragmatics.
Electromagnetic form factors of hyperons in the timelike region: A short review
Authors: Dai Ling-Yun , Haidenbauer Johann , Meißner Ulf-G.
Published: February 2025

We review recent experimental and theoretical results for the electromagnetic form factors of hyperons (Y) in the timelike region, accessible in the reactions e
+
e
- →
Y

Y. Specifically, we focus on the final states ΛΛ, ΛΣ0/Σ
0Λ, ΣΣ, ΞΞ, and ΩΩ. The Λ
cΛc system is also discussed.