bluuebunny/crossref_metadata_2025 huggingface dataset:
New solid forms of tetrahydrocurcumin with improved solubility
Authors: Tian Fanyu , Xia Mengyuan , Wang Hao , Zhang Bingrui , Ding Zhenfeng , Rong Xiaoyi , Zhu Bingqing , Mei Xuefeng
Published: April 2024

Tetrahydrocurcumin (THC), one of the active metabolites of curcumin, possesses pharmacological activities similar to those of curcumin, such as hypoglycemic, hypolipidemic and antioxidant effects.
Mechanistic study of the atomic layer deposition of cobalt: a combined mass spectrometric and computational approach
Authors: Donnecke Sofia , Paul Mathias , Williams Peter J. H. , Chan Serena , Tse Veronica , Sachdeva Jigyasa , Oliver Allen G. , McIndoe J. Scott , Paci Irina
Published: April 2024

Cobaltcarbonyl-tert-butylacetylene (CCTBA) is a conventional precursor for the selective atomic layer deposition of Co. Using an internal alkynyl ligand heightens the barrier for carbon deposition onto the silicon surface.
Silver nanoparticle-decorated NiFe2O4/CuWO4 heterostructure electrocatalyst for oxygen evolution reactions
Authors: Kumar Uttam , Sanket Kumar , Mandal Rupesh , Kumar De Arup , Shrivastava Anshu , Behera Shantanu K. , Sinha Indrajit
Published: April 2024

Ag nanoparticles decorated onto the NiFe2O4/CuWO4 heterostructure, with induced oxygen vacancies, improve the electrocatalytic properties of the oxygen evolution reaction.
Rational design of 2D Janus P3m1 M2N3 (M = Cu, Zr, and Hf) and their surface-functionalized derivatives: ferromagnetic, piezoelectric, and photocatalytic properties
Authors: Zhang Heng , Guégan Frédéric , Wang Junjie , Frapper Gilles
Published: April 2024

Nine 2D Janus nitrides, comprising P3m1 M2N3 and M2N3X (M = Cu, Zr, Hf; X = H, F, Cl), were rationally designed. DFT calculations were used to investigate their carrier mobilities, piezoelectric properties, and photocatalytic activities.
A two-step quadrature-based variational calculation of ro-vibrational levels and wavefunctions of CO2 using a bisector-x molecule-fixed frame
Authors: Wang Xiao-Gang , Carrington Tucker
Published: April 2024

In this paper, we propose a new two-step strategy for computing ro-vibrational energy levels and wavefunctions of a triatomic molecule and apply it to CO2.
Molecular insights into the nanoconfinement effect on the structure and dynamics of ionic liquids in carbon nanotubes
Authors: Liu Hao-Qian , Wang Yong-Lei , Li Bin
Published: April 2024

Exploration of the impact of charge states of carbon nanotubes on region-dependent properties of confined ionic liquids and the relation between ionic dynamics and interactions.
Insights into a surface-modified Li(Ni0.80Co0.15Al0.05)O2 cathode by atomic layer fluorination for improved cycling behaviour
Authors: Charles-Blin Youn , Hatim Oumaima , Clarac Mélissa , Perbost Anne-Marie , Liminana Solveine , Lopez Laura , Gimello Olinda , Guérin Katia , Dubois Marc , Deschamps Michael , Flahaut Delphine , Martinez Hervé , Monconduit Laure , Louvain Nicolas
Published: April 2024

Atomic layer fluorination of Li(Ni0.80Co0.15Al0.05)O2 leads to improved charge/discharge cyclability in Li-ion cells and limited electrolyte decomposition.
Combined effect of Cu0and oxygen vacancies in Cu-based zeolites enables highly efficient photo-Fenton-like performance for water purification
Authors: Zhang Wei , Wang Lan , Hou Chen , Zhu Zhiqiang , Lichtfouse Eric , Trapalis Christos , Wang Chuanyi
Published: April 2024

A novel environment-friendly oxygen-vacancy-rich Cu-doped zeolite decorated with Cu0(Cu0@CuZ) was fabricated to achieve the high-efficiency removal of refractory organic pollutants in a photo-Fenton-like reaction.
Accelerated basis-set convergence of coupled-cluster excitation energies using the density-based basis-set correction method
Authors: Traore Diata , Toulouse Julien , Giner Emmanuel
Published: April 2024

We present the first application to real molecular systems of the recently proposed linear-response theory for the density-based basis-set correction method [J. Chem. Phys., 158, 234107 (2023)].
Tailored carbon dioxide capacity in carboxylate-based ionic liquids
Authors: Scaglione Nicolas , Avila Jocasta , Padua Agilio , Costa Gomes Margarida
Published: April 2024

Tetraalkylphosphonium carboxylate ionic liquids absorb large quantities of carbon dioxide and are easily regenerated.
Enhancing the internal electric field via twinning for boosting photocatalytic plastic reformation and H2 production
Authors: Zhao Erling , Yin Pengfei , Du Kun , Lan Ning , Wang Quanlu , Guo Jiaxin , Wang Min , Ling Tao
Published: April 2024

Internal electric field of twinned ZnSe is beneficial for improving the transfer rate of charge carriers, accelerating the effective separation of electrons and holes, and boosting photocatalytic plastic reformation and H2 production.
Microfluidic confined acoustic streaming vortex for liposome synthesis
Authors: Xu Huihui , Wang Zhaoxun , Wei Wei , Li Tiechuan , Duan Xuexin
Published: April 2024

An acoustofluidic platform for controllable size liposome synthesis using microfluidic confined acoustic streaming vortex. It combines the features of both hydrodynamic flow focusing and rapid micro-mixing.
Expression of concern: Gadolinium embedded iron oxide nanoclusters as T1–T2 dual-modal MRI-visible vectors for safe and efficient siRNA delivery
Authors: Wang Xiaoyong , Zhou Zijian , Wang Zhiyong , Xue Yunxin , Zeng Yun , Gao Jinhao , Zhu Lei , Zhang Xianzhong , Liu Gang , Chen Xiaoyuan
Published: April 2024

Expression of concern for ‘Gadolinium embedded iron oxide nanoclusters as T1–T2 dual-modal MRI-visible vectors for safe and efficient siRNA delivery’ by Xiaoyong Wang et al., Nanoscale, 2013, 5, 8098–8104, https://doi.org/10.1039/C3NR02797J.
Intermolecular hydrogen bonding behavior of amino acid radical cations
Authors: Moppel Isabella , Elliott BarbaraAnn , Chen Shuming
Published: April 2024

DFT calculations revealed the structural and energetic impact of oxidation on major intermolecular hydrogen-bonding modes of amino acids.
Me3SiBr-promoted cascade electrophilic thiocyanation/cyclization of ortho-alkynylanilines to synthesize indole derivatives
Authors: Wang Qing , Shao Chukai , Hua Ruirui , Yin Hongquan , Chen Fu-Xue
Published: April 2024

A Me3SiBr promoted cascade electrophilic thiocyanation/cyclization of ortho-alkynylanilines with the electrophilic N-thiocyanatosuccinimide to afford 3-thiocyanatoindoles has been developed.
Total synthesis of jamaicamide B
Authors: Shigeta Ryosuke , Suzuki Takahiro , Kaneko Kazuki , Tanaka Hiroaki , Haishima Ibuki , Norio Kanata , Tanaka-Yanuma Ayano , Usuki Toyonobu
Published: April 2024

Jamaicamide B was isolated from the cyanobacterium Moorea producens in Jamaica and shows neurotoxicity. Herein we report the first total synthesis and structural confirmation of the marine natural product (9R)-jamaicamide B.
Photocontrol of catalysis in CuAAC reactions by air stable Cu(i) complexes of phenylazopyrazole-incorporated ligands
Authors: Gupta Debapriya , Gaur Ankit Kumar , Chauhan Deepanshu , Thakur Sandeep Kumar , Ashish  , Singh Sanjay , Rajaraman Gopalan , Venkataramani Sugumar
Published: April 2024

Switching catalytic activity by light’ - Phenylazopyrazole-incorporated Cu(i) complexes demonstrate phototriggered modulation of catalytic activity in CuAAC reaction between alkynes and azides.
A short-term rodent model for non-alcoholic steatohepatitis induced by a high-fat diet and carbon tetrachloride
Authors: Araujo Layanne C.C. , Dias Carolina C.B. , Sucupira Felipe G. , Ramalho Leandra N.Z. , Camporez João Paulo
Published: April 2024

Several models of mice-fed high-fat diets have been used to trigger non-alcoholic steatohepatitis and some chemical substances, such as carbon tetrachloride. The present study aimed to evaluate the joint action of a high-fat diet and CCl4 in developing a short-term non-alcoholic steatohepatitis model. C57BL6/J mice were divided into two groups: standard diet-fed (SD), the high-fat diet-fed (HFD) and HFD + fructose-fed and carbon tetrachloride (HFD+CCl4). The animals fed with HFD+CCl4 presented increased lipid deposition compared with both SD and HFD mice. Plasma cholesterol was increased in animals from the HFD+CCl4 group compared with the SD and HFD groups, without significant differences between the SD and HFD groups. Plasma triglycerides showed no significant difference between the groups. The HFD+CCl4 animals had increased collagen deposition in the liver compared with both SD and HFD groups. Hydroxyproline was also increased in the HFD+CCl4 group. Liver enzymes, alanine aminotransferase and aspartate aminotransferase, were increased in the HFD+CCl4 group, compared with SD and HFD groups. Also, CCl4 was able to trigger an inflammatory process in the liver of HFD-fed animals by promoting an increase of ∼2 times in macrophage activity, ∼6 times in F4/80 gene expression, and pro-inflammatory cytokines (IL-1b and TNFa), in addition to an increase in inflammatory pathway protein phosphorylation (IKKbp). HFD e HFD+CCl4 animals increased glucose intolerance compared with SD mice, associated with reduced insulin-stimulated AKT activity in the liver. Therefore, our study has shown that short-term HFD feeding associated with fructose and CCl4 can trigger non-alcoholic steatohepatitis and cause damage to glucose metabolism.
Understanding and computational design of genetic circuits of metabolic networks
Authors: Berkvens Alicia , Salinas Luis , Remeijer Maaike , Planqué Robert , Teusink Bas , Bruggeman Frank J.
Published: April 2024

The expression of metabolic proteins is controlled by genetic circuits, matching metabolic demands and changing environmental conditions. Ideally, this regulation brings about a competitive level of metabolic fitness. Understanding how cells can achieve a robust (close-to-optimal) functioning of metabolism by appropriate control of gene expression aids synthetic biology by providing design criteria of synthetic circuits for biotechnological purposes. It also extends our understanding of the designs of genetic circuitry found in nature such as metabolite control of transcription factor activity, promoter architectures and transcription factor dependencies, and operon composition (in bacteria). Here, we review, explain and illustrate an approach that allows for the inference and design of genetic circuitry that steers metabolic networks to achieve a maximal flux per unit invested protein across dynamic conditions. We discuss how this approach and its understanding can be used to rationalize Escherichia coli’s strategy to regulate the expression of its ribosomes and infer the design of circuitry controlling gene expression of amino-acid biosynthesis enzymes. The inferred regulation indeed resembles E. coli’s circuits, suggesting that these have evolved to maximize amino-acid production fluxes per unit invested protein. We end by an outlook of the use of this approach in metabolic engineering applications.
Neutron stars in accreting systems – Signatures of the QCD phase transition
Authors: Khosravi Largani Noshad , Fischer Tobias , Shibagaki Shota , Cerdá-Durán Pablo , Torres-Forné Alejandro
Published: April 2024

Neutron stars (NS) that are born in binary systems with a main-sequence star companion can experience mass transfer, resulting in the accumulation of material at the surface of the NS. This, in turn, leads to the continuous growth of the NS mass and the associated steepening of the gravitational potential. Supposing the central density surpasses the onset for the phase transition from nuclear, generally hadronic matter to deconfined quark-gluon plasma, which is a quantity currently constrained solely from an upper limit by asymptotic freedom in quantum chromodynamics (QCD), the system may experience a dynamic response due to the appearance of additional degrees of freedom in the equation of state (EOS). This dynamical response might give rise to a rapid softening of the EOS during the transition in the hadron-quark matter co-existence region. While this phenomenon has long been studied in the context of hydrostatic configurations, the dynamical implications of this problem are still incompletely understood. It is the purpose of the present paper to simulate the dynamics of NSs with previously accreted envelopes caused by the presence of a first-order QCD phase transition. Therefore, we employed the neutrino radiation hydrodynamics treatment based on the fully general relativistic approach in spherical symmetry, implementing a three-flavor Boltzmann neutrino transport and a microscopic model EOS that contains a first-order hadron-quark phase transition. The associated neutrino signal shows a sudden rise in the neutrino fluxes and average energies, becoming observable for the present generation of neutrino detectors for a galactic event, and a gravitational wave mode analysis revealed the behaviors of the dominant f mode and the first and the second gravity g modes that are excited during the NS evolution across the QCD phase transition.
Atmospherix
Authors: Hood Thea , Debras Florian , Moutou Claire , Klein Baptiste , Tremblin Pascal , Parmentier Vivien , Carmona Andres , Meech Annabella , Vénot Olivia , Masson Adrien , Petit Pascal , Vinatier Sandrine , Martioli Eder , Kiefer Flavien , Turbet Martin ,   the ATMOSPHERIX Consortium
Published: April 2024

Measuring the abundances of C- and O-bearing species in exoplanet atmospheres enables us to constrain the C/O ratio, which contains indications about the planet formation history. With a wavelength coverage going from 0.95 to 2.5 µm, the high-resolution (R ~ 70 000) spectropolarimeter SPIRou can detect spectral lines of major bearers of C and O in exoplanets. Here, we present our study of SPIRou transmission spectra of WASP-76 b acquired for the ATMOSPHERIX programme. We applied the publicly available data analysis pipeline developed within the ATMOSPHERIX Consortium, analysing the data using 1-D models created with the petitRADTRANS code, with and without a grey cloud deck. We report the detection of H2O and CO at a Doppler shift of around −6 km s−1, which is consistent with previous observations of the planet. Finding that a deep cloud deck is favoured, we measured a mass mixing ratio (MMR) log(H2O)MMR = −4.52 ± 0.77 and log(CO)MMR = −3.09 ± 1.05 consistent with a sub-solar metallicity to more than 1σ. We report 3σ upper limits for the abundances of C2H2, HCN, and OH. We estimated a C/O ratio of 0.94 ± 0.39 (~ 1.7 ± 0.7 × solar, with errors indicated corresponding to the 2σ values) for the limbs of WASP-76 b at the pressures probed by SPIRou. We used 1-D ATMO forward models to verify the validity of our estimation. Comparing them to our abundance estimations of H2O and CO, as well as our upper limits for C2H2, HCN and OH, we found that our results were consistent with a C/O ratio between 1 and 2 × solar, and hence with our C/O estimation. Finally, we found indications of asymmetry for both H2O and CO when investigating the dynamics of their signatures, pointing to a complex scenario possibly involving both a temperature difference between limbs and the presence of clouds being behind the asymmetry that this planet is best known for.
Ultrasound-Guided Modified Thread Carpal Tunnel Release for Carpal Tunnel Syndrome: A Pilot Study
Authors: Kim Jaewon , Kim Jae Min , Park Hae-Yeon , Kim In Jong
Published: April 2024

Purpose This study aimed to investigate the effectiveness and safety of modified thread carpal tunnel release (mTCTR) using Smartwire-01 in patients with carpal tunnel syndrome (CTS).

Materials and Methods Patients with CTS who required CTR were enrolled. Symptom severity and functional status were assessed using the Boston Carpal Tunnel Syndrome Questionnaire-Symptom Severity Scale (BCTQ-SSS) and Functional Status Scale (BCTQ-FSS), and pain was assessed using a numerical rating scale (NRS) at 4, 8, and 12 weeks after mTCTR. The scores were compared with the pre-procedural scores. The electrophysiologic study and median nerve cross-sectional area (CSA) measurements at the wrist before and 12 weeks after mTCTR were compared.

Results A total of 11 patients were included. No adverse effects were reported throughout the study period. The NRS, BCTQ-SSS, and BCTQ-FSS scores significantly improved at 4 weeks after mTCTR, and this improvement persisted throughout the follow-up period (NRS and BCTQ-SSS, P < 0.001; BCTQ-FSS, P = 0.012). After 12 weeks, the latency and velocity of the median sensory nerve action potential significantly improved, compared with those before mTCTR (latency, 5.4 ± 1.3 to 4.7 ± 1.1 ms, P = 0.01; velocity 27.8 ± 6.8 to 31.8 ± 7.4 m/s, P = 0.019). No significant change was observed in the median nerve CSA before and after mTCTR.

Conclusion mTCTR using Smartwire-01 is a safe and effective procedure and a possible alternative to surgery.
Language model-based labeling of German thoracic radiology reports
Authors: Wollek Alessandro , Haitzer Philip , Sedlmeyr Thomas , Hyska Sardi , Rueckel Johannes , Sabel Bastian O. , Ingrisch Michael , Lasser Tobias
Published: April 2024

The aim of this study was to explore the potential of weak supervision in a deep learning-based label prediction model. The goal was to use this model to extract labels from German free-text thoracic radiology reports on chest X-ray images and for training chest X-ray classification models.

The proposed label extraction model for German thoracic radiology reports uses a German BERT encoder as a backbone and classifies a report based on the CheXpert labels. For investigating the efficient use of manually annotated data, the model was trained using manual annotations, weak rule-based labels, and both. Rule-based labels were extracted from 66071 retrospectively collected radiology reports from 2017–2021 (DS 0), and 1091 reports from 2020–2021 (DS 1) were manually labeled according to the CheXpert classes. Label extraction performance was evaluated with respect to mention extraction, negation detection, and uncertainty detection by measuring F1 scores. The influence of the label extraction method on chest X-ray classification was evaluated on a pneumothorax data set (DS 2) containing 6434 chest radiographs with associated reports and expert diagnoses of pneumothorax. For this, DenseNet-121 models trained on manual annotations, rule-based and deep learning-based label predictions, and publicly available data were compared.

The proposed deep learning-based labeler (DL) performed on average considerably stronger than the rule-based labeler (RB) for all three tasks on DS 1 with F1 scores of 0.938 vs. 0.844 for mention extraction, 0.891 vs. 0.821 for negation detection, and 0.624 vs. 0.518 for uncertainty detection. Pre-training on DS 0 and fine-tuning on DS 1 performed better than only training on either DS 0 or DS 1. Chest X-ray pneumothorax classification results (DS 2) were highest when trained with DL labels with an area under the receiver operating curve (AUC) of 0.939 compared to RB labels with an AUC of 0.858. Training with manual labels performed slightly worse than training with DL labels with an AUC of 0.934. In contrast, training with a public data set resulted in an AUC of 0.720.

Our results show that leveraging a rule-based report labeler for weak supervision leads to improved labeling performance. The pneumothorax classification results demonstrate that our proposed deep learning-based labeler can serve as a substitute for manual labeling requiring only 1000 manually annotated reports for training.

Wollek A, Haitzer P, Sedlmeyr T et al. Language modelbased labeling of German thoracic radiology reports. Fortschr Röntgenstr 2024; DOI 10.1055/a-2287-5054
Synthesis and Dynamic Behaviors of 5,7,8,10-Tetraphenyl-1,14-dianilinotripyrrins
Authors: Seki Shu , Tanaka Takayuki , Nishiyama Ayane , Matsuo Yusuke
Published: April 2024

5,7,8,10-Tetraphenyl-1,14-di(arylamino)tripyrrins have been synthesized via 5,7,8,10-tetraphenyltripyrrane. The structures and dynamic equilibrium between single helical monomer and double helical dimer were analyzed by 1H NMR spectra and X-ray diffraction analysis. Their dimerization association constants in CDCl3 are larger than those of previously reported dianilinotripyrrin derivatives. In DMSO, they exhibited luminescence around 700 nm as a consequence of restricted rotational relaxation by the phenyl groups installed at the 7,8-positions.
Quantum statistical mechanics and the boundary of modular curves
Authors: Marcolli Matilde , Panangaden Jane
Published: April 2024

The theory of limiting modular symbols provides a noncommutative geometric model of the boundary of modular curves that includes irrational points in addition to cusps. A noncommutative space associated to this boundary is constructed, as part of a family of noncommutative spaces associated to different continued fractions algorithms, endowed with the structure of a quantum statistical mechanical system. Two special cases of this family of quantum systems can be interpreted as a boundary of the system associated to the Shimura variety of GL2 and an analog for SL2. The structure of equilibrium states for this family of systems is discussed. In the geometric cases, the ground states evaluated on boundary arithmetic elements are given by pairings of cusp forms and limiting modular symbols.
Creating and studying a scaled interplanetary coronal mass ejection
Authors: Bryant K. , Young R. P. , LeFevre H. J. , Kuranz C. C. , Olson J. R. , McCollam K. J. , Forest C. B.
Published: April 2024

The Sun, being an active star, undergoes eruptions of magnetized plasma that reach the Earth and cause the aurorae near the poles. These eruptions, called coronal mass ejections (CMEs), send plasma and magnetic fields out into space. CMEs that reach planetary orbits are called interplanetary coronal mass ejections (ICMEs) and are a source of geomagnetic storms, which can cause major damage to our modern electrical systems with limited warning. To study ICME propagation, we devised a scaled experiment using the Big Red Ball (BRB) plasma containment device at the Wisconsin Plasma Physics Laboratory. These experiments inject a compact torus of plasma as an ICME through an ambient plasma inside the BRB, which acts as the interplanetary medium. Magnetic and temperature probes provide three-dimensional magnetic field information in time and space, as well as temperature and density as a function of time. Using this information, we can identify features in the compact torus that are consistent with those in real ICMEs. We also identify the shock, sheath, and ejecta similar to the structure of an ICME event. This experiment acts as a first step to providing information that can inform predictive models, which can give us time to shield our satellites and large electrical systems in the event that a powerful ICME were to strike.
Feasibility and performance of the staged Z-pinch: A one-dimensional study with FLASH and MACH2
Authors: Hansen E. C. , Garcia-Rubio F. , Adams M. B. P. , Fatenejad M. , Moczulski K. , Ney P. , Rahman H. U. , Reyes A. C. , Ruskov E. , Tranchant V. , Tzeferacos P.
Published: April 2024

Z-pinch platforms constitute a promising pathway to fusion energy research. Here, we present a one-dimensional numerical study of the staged Z-pinch (SZP) concept using the FLASH and MACH2 codes. We discuss the verification of the codes using two analytical benchmarks that include Z-pinch-relevant physics, building confidence on the codes' ability to model such experiments. Then, FLASH is used to simulate two different SZP configurations: a xenon gas-puff liner (SZP1*) and a silver solid liner (SZP2). The SZP2 results are compared against previously published MACH2 results, and a new code-to-code comparison on SZP1* is presented. Using an ideal equation of state and analytical transport coefficients, FLASH yields a fuel convergence ratio (CR) of approximately 39 and a mass-averaged fuel ion temperature slightly below 1 keV for the SZP2 scheme, significantly lower than the full-physics MACH2 prediction. For the new SZP1* configuration, full-physics FLASH simulations furnish large and inherently unstable CRs (>300) but achieve fuel ion temperatures of many kilo-electron volts. While MACH2 also predicts high temperatures, the fuel stagnates at a smaller CR. The integrated code-to-code comparison reveals how magnetic insulation, heat conduction, and radiation transport affect platform performance and the feasibility of the SZP concept.
Antiferromagnetic droplet soliton driven by spin current
Authors: Ovcharov Roman V. , Hamdi Mohammad , Ivanov Boris A. , Åkerman Johan , Khymyn Roman S.
Published: April 2024

We demonstrate that a spin current flowing through a nanocontact into a uniaxial antiferromagnet with first- and second-order anisotropy can excite a self-localized dynamic magnetic soliton, known as a spin-wave droplet in ferromagnets. The droplet nucleates at a certain threshold current with the frequency of the Néel vector precession laying below the antiferromagnetic resonance. The frequency exhibits nonlinear behavior with the increase in the applied current. At the high value of the applied torque, the soliton mode transforms, and the oscillator emits spin waves propagating in the antiferromagnetic layer.
Epitaxial twin coupled microstructure in GeSn films prepared by remote plasma enhanced chemical vapor deposition
Authors: Jiang Jiechao , Chetuya Nonso Martin , Ngai Joseph H. , Grzybowski Gordon J. , Meletis Efstathios I. , Claflin Bruce
Published: April 2024

Growth of GeSn films directly on Si substrates is desirable for integrated photonics applications since the absence of an intervening buffer layer simplifies device fabrication. Here, we analyze the microstructure of two GeSn films grown directly on (001) Si by remote plasma-enhanced chemical vapor deposition (RPECVD): a 1000 nm thick film containing 3% Sn and a 600 nm thick, 10% Sn film. Both samples consist of an epitaxial layer with nano twins below a composite layer containing nanocrystalline and amorphous. The epilayer has uniform composition, while the nanocrystalline material has higher levels of Sn than the surrounding amorphous matrix. These two layers are separated by an interface with a distinct, hilly morphology. The transition between the two layers is facilitated by formation of densely populated (111)-coupled nano twins. The 10% Sn sample exhibits a significantly thinner epilayer than the one with 3% Sn. The in-plane lattice mismatch between GeSn and Si induces a quasi-periodic misfit dislocation network along the interface. Film growth initiates at the interface through formation of an atomic-scale interlayer with reduced Sn content, followed by the higher Sn content epitaxial layer. A corrugated surface containing a high density of twins with elevated levels of Sn at the peaks begins forming at a critical thickness. Subsequent epitaxial breakdown at the peaks produces a composite containing high levels of Sn nanocrystalline embedded in lower level of Sn amorphous. The observed microstructure and film evolution provide valuable insight into the growth mechanism that can be used to tune the RPECVD process for improved film quality.
A synthetic position decoding technology for rotary transformers based rotor position measurement system
Authors: Cai Jun , Dou Xiaolan , Liu Zeyuan , Cheok Adrian David , Ying Yan , Zhang Xin
Published: April 2024

This article proposes a rotary transformer position decoding scheme for motor drive control. In this scheme, a simple analog circuit is used to design the excitation circuit and signal conditioning circuit. Demodulate the modulated sine/cosine signal through software and decode it through a phase locked loop (PLL) to obtain the implemented position signal. This scheme completely avoids the use of traditional, specialized decoding chips. At the same time, in order to make the position decoding scheme applicable to different motor drive control platforms, a single-cycle partition average based pulse signal estimation method is proposed for converting the angle position into pulse signals similar to the output of an encoder’s phases A, B, and Z, which are referred to as A/B/Z signals in the paper. In order to experimentally validate the proposed scheme, a software decoding platform based on the STM32F407 was built and compared with the decoding results of the chip. The effectiveness and accuracy of the proposed scheme were verified, and it can be effectively applied in the field of motor drive control.
Numerical modeling of self-aerated flows: Turbulence modeling and the onset of air entrainment
Authors: Zabaleta F. , Bombardelli F. A. , Márquez Damián S.
Published: April 2024

Numerical modeling of self-aerated flows is essential for understanding water systems and designing hydraulic structures. This work discusses and extends a theoretical/numerical model to represent air entrainment in self-aerated flows, which includes a criterion to define the occurrence of air entrainment, based on a balance between disturbing and stabilizing energies. The impact of the turbulence closure on the modeling of the onset of air entrainment and the distribution of bubble concentration is studied with particular emphasis. This work shows that uniform-density formulations of Reynolds-averaged Navier–Stokes closures lead to severe overprediction of air entrainment due to unphysical transport of turbulent kinetic energy generated in the air phase to the water phase. In contrast, combining variable-density turbulence closures with the energy balance criterion enables accurate prediction of the regions where air is entrained for stepped spillways and plunging jets. The choice of turbulence closure significantly influences the proposed criterion, emphasizing the importance of selecting an appropriate closure for an accurate description of the air entrainment process. Based on the conducted tests, the standard k−ε and buoyancy modified k−ε models better predict the onset of air entrainment and bubble distribution in stepped spillways, while the k−ω SST model proves to be more effective in capturing air entrainment at the impingement point in plunging jets. This study expands the capabilities of numerical models in predicting air entrainment and provides valuable insights into the effects and interrelations of the turbulence modeling, the air entrainment occurrence criteria, and the bubble transport equations.
Equilibrium structure and shape of Ag and Pt nanoparticles grown on silica surfaces: From experimental investigations to the determination of a metal–silica potential
Authors: Ait Hellal F. , Andreazza-Vignolle C. , Andreazza P. , Puibasset J.
Published: April 2024

A combination of experimental and numerical investigations on metallic silver and platinum nanoparticles deposited on silica substrates is presented, with a focus on metal–substrate interactions. Experimentally, the nanoparticles, obtained by ultra-high vacuum atom deposition, are characterized by grazing-incidence small-angle x-ray scattering and high resolution transmission electronic microscopy to determine their structure and morphology and, in particular, their aspect ratio (height/diameter), which quantifies the metal–substrate interaction, from the as-grown to equilibrium state. Numerically, the interactions between the metal and the silica species are modeled with the Lennard-Jones (12, 6) potential, with two parameters for each metal and silica species. The geometric parameters were found in the literature, while the energetic parameters were determined from our experimental measurements of the aspect ratio. The parameters are as follows: σAg–O = 0.278 nm, σAg–Si = 0.329 nm, ɛAg–O = 75 meV, and ɛAg–Si = 13 meV for Ag–silica and σPt–O = 0.273 nm, σPt–Si = 0.324 nm, ɛPt–O = 110 meV, and ɛPt–Si = 18 meV for Pt–silica. The proposed Ag–silica potential reproduces quantitatively the unexpected experimental observation of the variation of the aspect ratio for Ag nanoparticles larger than 5 nm, which has been interpreted as a consequence of the silica roughness. The nanoparticle orientation, structure, and disorder are also considered. This metal–silica potential for Ag and Pt should be helpful for further studies on pure metals as well as their alloys.
Enhancing carrier collection in CsPbBr3 solar cells through crystal orientation and defect passivation
Authors: Dong Haotian , Wang Zijian , Zhang Qiang , Zhang Zhen , Zhu Zhi , Han Xiaopeng , Gu Jun , Wang Xiaoyong , Yang Jie , Yu Tao , Bao Chunxiong , Zou Zhigang
Published: April 2024

All-inorganic carbon-based CsPbBr3 perovskite solar cells (PSCs) have gained growing interest for their remarkable stability. However, compared to their organic–inorganic hybrid counterparts, there is still substantial room for improving their performance primarily due to the inferior photogenerated carrier collection efficiency. Here, we employ area-dependent transient photocurrent to assess the carrier transit time in CsPbBr3 PSCs, revealing that an extended carrier transit time relative to the lifetime significantly contributes to their low carrier collection efficiency. To address this challenge, we narrow the gap between carrier transit time and lifetime by introducing a dual-functional additive, serving to facilitate both crystallization orientation and defect passivation. Consequently, we achieve enhanced short-circuit current and efficiency in CsPbBr3 PSCs.
Engineering the topological states of Weyl ferromagnetic CoxMnGay films grown by molecular beam epitaxy
Authors: Ren Lizhu , Zhao Tieyang , Chen Jingsheng , Teo Kie Leong
Published: April 2024

Due to its nontrivial topological state, a magnetic Weyl semimetal often exhibits exotic transport properties that are important for both fundamental physics and potential spintronics applications. In this Letter, we investigate the composition dependences of the structural order, magnetism, and transport properties for the epitaxial Heusler alloy CoxMnGay (CMG) topological Weyl semimetal films grown via molecular beam epitaxy. Our results show that the saturated magnetization, anomalous Hall conductivity, and anomalous Hall angle of CMG are influenced by its composition and structural order. Specifically, we observed that the optimized L21–Co2MnGa alloy exhibits a high intrinsic anomalous Hall conductivity of approximately 913 Ω−1 cm−1 at its maximum, which is attributed to the substantial Berry curvature within its electronic band structures. This study provides valuable insights into how to engineer the topological ferromagnetic state of the Weyl semimetals for future applications.
Strain-tunable ferromagnetism in 2D non-van-der-Waals CuCr2X4 (X = S, Se)
Authors: Li Shasha , Bo Xiangyan , Fu Lei , Liu Chang , Li Feng , Pu Yong
Published: April 2024

The magnetic property of non-van-der-Waals CuCr2X4(X = S, Se) monolayer and its strain dependence are investigated systematically from first principles. The CuCr2X4 monolayers are intrinsic ferromagnetic (FM) metals, and the magnetism is mainly contributed by Cr atoms. Considerable magnetic anisotropy energy of 1.28 meV per Cr is found in CuCr2Se4 monolayer, which is one order of magnitude higher than the 0.14 meV per Cr found in CuCr2S4 monolayer. Their easy magnetization axes are along the in-plane directions, which is rare in 2D materials. By performing in-plane biaxial strain, the FM ground states of CuCr2X4 monolayers transform to antiferromagnetic (AFM) states when the compressive strain is larger than 6%, while relatively small tensile strain of 2% would induce the transition between FM and AFM for CuCr2Se4 monolayer. Moreover, we find that room-temperature Curie temperature can be realized in CuCr2X4 monolayer with appropriate tensile strain, indicating that the strained CuCr2X4 monolayer is promising in future 2D spintronic device applications and deserves further experimental exploration.
The performance of OPC and OPC3 water models in predictions of 2D structures under nanoconfinement
Authors: Wei Laiyang , Li Xiaojiao , Bai Qi , Kang Jing , Song Jueying , Zhu Shuang , Shen Lin , Wang Huan , Zhu Chongqin , Fang Weihai
Published: April 2024

Nanoconfined water plays an important role in broad fields of science and engineering. Classical molecular dynamics (MD) simulations have been widely used to investigate water phases under nanoconfinement. The key ingredient of MD is the force field. In this study, we systematically investigated the performance of a recently introduced family of globally optimal water models, OPC and OPC3, and TIP4P/2005 in describing nanoconfined two-dimensional (2D) water ice. Our studies show that the melting points of the monolayer square ice (MSI) of all three water models are higher than the melting points of the corresponding bulk ice Ih. Under the same conditions, the melting points of MSI of OPC and TIP4P/2005 are the same and are ∼90 K lower than that of the OPC3 water model. In addition, we show that OPC and TIP4P/2005 water models are able to form a bilayer AA-stacked structure and a trilayer AAA-stacked structure, which are not the cases for the OPC3 model. Considering the available experimental data and first-principles simulations, we consider the OPC water model as a potential water model for 2D water ice MD studies.
An analytical study for predicting incipient motion velocity of sediments in ecological open channel flows
Authors: Zhang Jiao , Mi Zhangyi , Wang Wen , Li Zhanbin , Li Peng , Xu Jiakuan , Li Jing , Wang Huilin , Wu Zi
Published: April 2024

Sediment movements on the riverbeds are crucial in fluvial processes. Therefore, studying incipient sediment motion is valuable for predicting changes in sediment behavior. In this study, the influence of aquatic vegetation is introduced into the momentum balance equation under the condition of a bare bed. The presented model for incipient sediment motion in open channels covered by vegetation is derived, in consideration of vegetation density and relative submergence. This study simplifies the model format. The model and its coefficients demonstrate good applicability to various working conditions without requiring numerous changes. The predicted velocity determined by the proposed model is validated against experimental data. Results show excellent agreement between the two in various scenarios, including combinations of rigid or flexible conditions and submerged or emergent states. Additionally, the velocity for incipient sediment motion is observed to decrease with increasing vegetation density. However, a further increase in vegetation density may amplify vegetation resistance, hindering incipient sediment motion. Meanwhile, sediment movement becomes challenging as water depth increases, assuming that flow discharge and vegetation conditions remain constant.
Direct numerical simulations of high-enthalpy supersonic turbulent channel flows including finite-rate reactions
Authors: Chen Xiao-Ping , Yang Yu-Ting , Zhao Shuo
Published: April 2024

Direct numerical simulations of temporally evolving high-enthalpy supersonic turbulent channel flows are conducted at a Mach number of 3.0 and Reynolds number of 4880 under isothermal wall conditions. Air is assumed to behave as a five-species mixture, and chemical non-equilibrium and equilibrium assumptions are adopted to investigate the influence of finite-rate reactions on the turbulent statistics and large-scale structures. The two wall temperatures of 1733.2 and 3500 K are such that the mixture components undergo strong dissociation and recombination reactions along the channel. Investigation shows that the turbulent intensity is weakened and the mean and fluctuating temperatures are smaller when finite-rate reactions are considered. The mean dissociation degree is a quadratic function of the normal position, and its curvature under the chemical non-equilibrium assumption is greater than that under the chemical equilibrium assumption. The fluctuating mass fractions of the generated species seem to decrease slightly in the near-wall region, and their distributions are obviously different from those of the fluctuating velocity and fluctuating temperature. Finite-rate reactions increase the proportion of turbulent kinetic energy production in the skin friction decomposition, especially when the wall temperature is 3500 K. The large-scale structures visualized by the cross correlation between temperature and species mass fraction become stronger in the normal direction. The turbulent Schmidt number and several velocity–temperature correlations, including the recovery enthalpy and strong Reynolds analogy, are insensitive to the chemical reaction rate and wall temperature.
Formation of a two-dimensional helical square tube ice in hydrophobic nanoslit using the TIP5P water model
Authors: Li Jiaxian , Zhu Chongqin , Zhao Wenhui , Gao Yurui , Bai Jaeil , Jiang Jian , Zeng Xiao Cheng
Published: April 2024

In extreme and nanoconfinement conditions, the tetrahedral arrangement of water molecules is challenged, resulting in a rich and new phase behavior unseen in bulk phases. The unique phase behavior of water confined in hydrophobic nanoslits has been previously observed, such as the formation of a variety of two-dimensional (2D) ices below the freezing temperature. The primary identified 2D ice phase, termed square tube ice (STI), represents a unique arrangement of water molecules in 2D ice, which can be viewed as an array of 1D ice nanotubes stacked in the direction parallel to the confinement plane. In this study, we report the molecular dynamics (MD) simulations evidence of a novel 2D ice phase, namely, helical square tube ice (H-STI). H-STI is characterized by the stacking of helical ice nanotubes in the direction parallel to the confinement plane. Its structural specificity is evident in the presence of helical square ice nanotubes, a configuration unseen in both STI and single-walled ice nanotubes. A detailed analysis of the hydrogen bonding strength showed that H-STI is a 2D ice phase diverging from the Bernal–Fowler–Pauling ice rules by forming only two strong hydrogen bonds between adjacent molecules along its helical ice chain. This arrangement of strong hydrogen bonds along ice nanotube and weak bonds between the ice nanotube shows a similarity to quasi-one-dimensional van der Waals materials. Ab initio molecular dynamics simulations (over a 30 ps) were employed to further verify H-STI’s stability at 1 GPa and temperature up to 200 K.
A non-conformal domain decomposition method utilizing rotating subdomains and non-matching grids for periodic metamaterial simulation
Authors: Liu Hangxin , Xu Li , Wang Hao , Liu Bingqi , Yuan Xuesong , Li Bin
Published: April 2024

Electromagnetic metamaterials possess characteristics such as having large-scale, periodic, multi-media, and complex geometric structures, making them highly suitable for simulation using the finite element domain decomposition method (DDM). This work proposes a non-conformal DDM for simulating finite-period metamaterials, achieving simulation with a minimal number of domains while significantly reducing computational resource consumption. First, the computational domain of the periodic metamaterial is partitioned into several non-conformal hexahedral subdomains. Subsequently, a limited number of non-repetitive subdomain models with non-matching grids are constructed, leveraging the three-dimensional rotational and translational properties of these subdomains to facilitate simulation. By eliminating the necessity to construct models for every subdomain, a substantial reduction in memory consumption is achieved. Second, an iteration method for solving the matrix equations of subdomains is enhanced by introducing a multifrontal block incomplete Cholesky decomposition preconditioner, thereby enhancing the computational efficiency of matrix equations with a large number of unknowns. Meanwhile, parallel computing techniques are employed to accelerate the proposed method. Finally, we integrate the aforementioned method into a solver and leverage it to develop an electromagnetic simulation tool tailored for metamaterials. The tool is employed to simulate metamaterial structures of varying scales, resulting in notable reductions in both memory and time consumption while maintaining accuracy comparable to commercial software.
Topological and chiral superconductor nanoarchitectures
Authors: Córdoba Rosa , Fomin Vladimir M.
Published: April 2024

3D nano-superconductors, with non-trivial geometry-driven topological phenomena, stand as promising systems for the future evolution of efficient and multifunctional technologies. However, the substantial challenges inherent in the experimental work, particularly regarding the fabrication and characterization of 3D nanoscale geometries and unconventional topologies of superconducting states, have confined the majority of investigations in this domain until recently to the realms of computational and theoretical studies. We overview the recent advancements in fabricating superconductor 3D nanoarchitectures and unveiling their fascinating physical properties that occur due to the geometry-induced topology and chirality, which offer a broad spectrum of applications of these nanostructures for the front-line development of various modern technologies.
Molding the acoustic cavity–analyzing the influence of toroidal vortex development on acoustic multi-bubble macrostructures under different ultrasonic horn tip diameters
Authors: Al Bishtawi Basel , Mustapha Khameel Bayo , Scribano Gianfranco
Published: April 2024

The acoustic cavity structure typically experiences a sequence of transfigurations during its sinusoidal growth–collapse cycle. However, upon examining the cavity structure in aqueous bodies, it appears that the growth structure attained falls between two geometrical structures, namely, mushroom-like structure (MBS) and cone-like bubble structure (CBS), based on the actuated ultrasonic horn tip diameter. With the recurring observations of the emergence of proximal toroidal vortices, the present investigation conducts a numerical analysis exploring the vortex development under 3, 6, 13, 16, and 19 mm horn tips to establish a potential correlation between the vortex and the cavity structure. The study presents a computational fluid dynamic investigation to capture the nature of the vortex evolution, in terms of size and position, and its respective cavitation development. The first indicator of potential correlation was the equivalency of the vortex expansion–contraction frequency and the cavity's sub-harmonic frequency. It has been found that the cavity structure is molded into MBS by the presence of a symmetric locomotive vortex structure that extends up to 1.5 times the horn tip diameter. Meanwhile, CBS is observed to take shape in the presence of an eccentric locomotive vortex that attains a size within 0.2–0.6 times the horn tip diameter. The significance of the vortex size and position is also observed in the cavity's collapse, as the vortex appears to govern the ability of the cavity impinging jet to initialize the collapse phase.
Direct recording and reading of mechanical force by afterglow evaluation of multi-piezo mechanoluminescent material Li0.12Na0.88NbO3 on well-designed morphotropic phase boundary
Authors: Uchiyama Tomoki , Atsumi Taisei , Otonari Koki , Fujio Yuki , Zheng Xu-Guang , Xu Chao-Nan
Published: April 2024

Mechanoluminescence (ML) refers to the photon emission from materials subjected to mechanical stimuli. A general concept concerning ML materials is that they cannot directly record a stress history (mechanical record; MR). Here, we report an approach that retrieves a quantitative recording of stress history through the afterglow characteristics analysis of a specific multi-piezo ML material Li0.12Na0.88NbO3:Pr (LNNO), which has been designated to exist near the structural phase boundary of rhombohedral R3c and orthorhombic P21ma. Contrary to the general expectation that the afterglow characteristics are irrelevant to mechanical loading history, LNNO was strongly correlated with the stress distribution after UV excitation. This enabled us to read the recorded stress precisely from the afterglow image of the material. Furthermore, the spatial distribution of the MR was also realized, showing the capability of the readout of stress history in both time and space. This unusual MR function is attributed to eliminating shallow trap sites, which affected the afterglow characteristics upon applying mechanical load.