bluuebunny/crossref_metadata_2025 huggingface dataset:
Encapsulated stretchable amphibious strain sensors
Authors: Wu Shuang , Kim Doyun , Tang Xiaoqi , King Martin W. , Zhu Yong
Published: August 2024

A novel amphibious strain sensor with a periodic cut pattern and a unique interface design offers an unprecedented combination of high gauge factor, linear sensing response, and excellent stability in water/saline solution.
Covalent functionalization by using blue light activated radicals: on the reaction mechanisms of arylazo sulfone binding on graphene
Authors: Mameli Alessandro , Kovtun Alessandro , Jones Derek , Benekou Vasiliki , Palermo Vincenzo , Bandini Marco , Melucci Manuela
Published: August 2024

Covalent functionalization of graphene presents a pivotal strategy to enhance its surface properties and overcome inherent chemical inertness.
In situ transformation of a Bi-based MOF to a highly active catalyst for CO2 reduction
Authors: Liu Chan , Wu Zeliang , Li Yuhan , Yu Haoming , Chen Shixia , Hong Wei , Deng Shuguang , Wang Jun
Published: August 2024

An in situ reconstruction of a Bi-MOF into an efficient catalyst to reduce CO2 to formate was demonstrated.
Multifunctional phase-change composites for green electromagnetic interference shielding and thermal response prepared under the guidance of an impedance matching strategy
Authors: He Jie , Wu Jiaozu , Park Chul B. , Gong Pengjian , Liang Chaobo , Li Guangxian
Published: August 2024

Schematic diagram of heat dissipation of composite materials.
Functionalized SBA-15: engineering, detailed study on release and kinetics of alendronate as well as its anti-tumour properties towards osteosarcoma
Authors: Patel Anjali , Mehta Shivangi
Published: August 2024

A biocompatible drug delivery system based on 12-tungstophosphoric acid functionalized SBA-15 for the controlled release of alendronate was synthesized and its anti-tumour properties towards osteosarcoma was explored.
Electrospun dressings with a dual release functionality of two anti-inflammatory active ingredients
Authors: Gürtler Anna-Lena , Sirois Jonathan P. , Lang Julia C. , Melican Keira , Rades Thomas , Heinz Andrea
Published: August 2024

Development and in vitro as well as ex vivo characterization of different types polycaprolactone-based electrospun dressings containing the two anti-inflammatory active ingredients hydrocortisone and salicylic acid.
Supramolecular hydrogels enable co-delivery of chemotherapeutics with synergistic efficacy against patient-derived glioblastoma cells and spheroids
Authors: Cavanagh Robert J. , Baquain Saif , Alexander Cameron , Scherman Oren A. , Rahman Ruman
Published: August 2024

Drug combinations have been shown to be highly effective in many cancer therapies but the ratios of the individual drugs must be adjusted carefully and formulated appropriately to ensure synergistic action.
Heavy atom-doped thermally activated delayed fluorescence cesium zirconium halides for efficient X-ray imaging
Authors: Yang Dandan , Li Ling , Liu Shijia , Hu Xudong , Zhang Xuebin , Xu Zhiheng , Guo Shiying , Wang Bing , Tang Xiaobin , Chen Zhuang , Li Xiaoming , Xu Qin , Zeng Haibo
Published: August 2024

A heavy atom (Hf)-doped Cs2ZrCl6 scintillator with strong blue emission, large Stokes shift, and smaller ΔE(S1–T1) shows a higher light yield, a low detection limit, and a higher spatial resolution, as well as good irradiation stability.
Visible-light mediated selective phosphonylation modification of tryptophan residues in oligopeptides
Authors: Xiong Wenfang , He Junye , Liu Jinyao , Chen Peiru , Xu Shiqi , Liu Yipeng , Chen Shiting , You Yuanyuan , Chen Zhenyu , Zhao Jinwu
Published: August 2024

A direct C2-H phosphonylation strategy driven by visible light for specific modification of tryptophan-containing peptides has been reported, providing a plethora of phosphorylated tryptophan-containing peptides
Solar power conversion: CuI hole transport layer and Ba3NCl3 absorber enable advanced solar cell technology boosting efficiency over 30%
Authors: Ghosh Avijit , Al Hossain Newaz Abdullah , Baki Abdullah Al , Awwad Nasser S. , Ibrahium Hala A. , Hossain Mohammad Shakhawat , Rahman Sonic Md Muminur , Islam Md Saiful , Rahman Md Khaledur
Published: August 2024

Researchers are becoming more interested in novel barium-nitride-chloride (Ba3NCl3) hybrid perovskite solar cells (HPSCs) due to their remarkable semiconductor properties.
Process knowledge for drug substance production via kinetic modeling, parameter estimability analysis and reaction optimization
Authors: Moshiritabrizi Iman , McMullen Jonathan P. , Wyvratt Brian M. , McAuley Kimberley B.
Published: August 2024

A mechanistic model that accounts for uncertain inputs is developed to study a key step in production of islatravir, an HIV drug.
Synergistic surface modulation with isotropic 2D GA2PbI4 and Lewis base enhances efficiency and stability of perovskite solar cells
Authors: Song Peiquan , Shen Lina , Zheng Lingfang , Hou Enlong , Xu Peng , Yang Jinxin , Tian Chengbo , Wei Zhanhua , Zhang Xiaguang , Xie Liqiang
Published: August 2024

Guanidinium acetate (GAAc) was applied to treat a perovskite film for fabricating n–i–p perovskite solar cells. The synergistic effect of GA+ and Ac− on regulating the perovskite surface enabled high-efficiency and stable perovskite solar cells.
Power generation from n-type NbCo1−xNixSn and p-type NbFe1−xMnxSb ternary half-Heusler compounds: from materials development to module fabrication
Authors: Piyasin Piyawat , Pinitsoontorn Supree , Sauerschnig Philipp , Imasato Kazuki , Ohta Michihiro
Published: August 2024

The thermoelectric figure of merit zT in n-type Ni-doped NbCoSn and p-type Mn-doped NbFeSb half-Heusler (HH) compounds was successfully improved using the 18 valence electron count concept, demonstrating reliable power generation in HH-based modules.
Asynchronous Wireless Signal Modulation Recognition Based on In‐Phase Quadrature Histogram
Authors: Zhang Xu , Hui Xi , Wan Pengwu , Hui Tengfei , Li Xiongfei
Published: August 2024

Automatic modulation recognition is a key technology in the field of signal processing. Conventional recognition methods suffer from low recognition accuracy at low signal‐to‐noise ratios (SNR), and when the signal frequency is unstable or there is asynchronous sampling, the performance of conventional recognition methods will deteriorate or even fail. To address these challenges, deep learning‐based modulation mode recognition technique is investigated in this paper for low‐speed asynchronous sampled signals under channel conditions with varying SNR and delay. Firstly, the low‐speed asynchronous sampled signals are modeled, and their in‐phase quadrature components are used to generate a two‐dimensional asynchronous in‐phase quadrature histogram. Then, the feature parameters of this 2D image are extracted by radial basis function neural network (RBFNN) to complete the recognition of the modulation mode of the input signal. Finally, the accuracy of the method for seven modulation methods is verified by extensive simulations. The experimental results show that under the channel model of additive white Gaussian noise (AWGN), when the SNR of the input signal with low‐speed asynchronous sampling is 6 dB, more than 95% of the average recognition accuracy can be achieved, and the effectiveness and robustness of the proposed scheme are verified by comparative experiments.
Improved hybrid estimation of distribution algorithm for distributed parallel assembly permutation flow shop scheduling problem
Authors: Du Lizhen , Wang Xintao , Tang Jiaqi , Xu Chuqiao , Qin Guanxing
Published: August 2024

Distributed assembly permutation flow shop scheduling problem is the hot spot of distributed pipeline scheduling research; however, parallel assembly machines are often in the assembly stage. Therefore, we propose and study distributed parallel assembly permutation flow shop scheduling problem (DPAPFSP). This aims to enhance the efficiency of multi‐factory collaborative production in a networked environment. Initially, a corresponding mathematical model was established. Then, an improved hybrid distribution estimation algorithm was proposed to minimize the makespan. The algorithm adopts a single‐layer permutation encoding and decoding strategy based on the rule of the Earliest Finished Time. A local neighbourhood search based on critical paths is performed for the optimal solution using five types of neighborhood design. A dual sampling strategy based on repetition rates was introduced to ensure the diversity of the population in the later periods of iteration. Simulated annealing searching was applied to accelerate the decline of optimal value. Finally, we conduct simulation experiments using 900 arithmetic cases and compare the simulation experimental data of this algorithm with the other four existing algorithms. The analysis results demonstrate this improved algorithm is very effective and competitive in solving the considered DPAPFSP.
Videogestützte Elternberatung und Beurteilung der Entwicklung des elterlichen Kommunikationsverhaltens mit ihren Cochlea Implantat-versorgten Kindern – Fallstudie
Authors: Martsch Anke , Metzeld Dennis , Helbig Silke , Seebens Yvonne , Schäfer Karolin
Published: August 2024

Videogestützte Beratungsangebote sind Teil familienzentrierter Konzepte in der Therapie und Frühförderung von Kindern nach Cochlea Implantat-Versorgung. Ziel dieser retrospektiven Längsschnitt-Fallstudie ist es, zu untersuchen, ob mittels EKIE-hör (Eltern-Kind-Interaktionseinschätzskala) elterliches Interaktionsverhalten mit ihrem CI-versorgten Kind im individuellen Einzelfall im Verlauf adäquat bewertet werden kann. Zudem soll der Einfluss videogestützter Beratung auf das Interaktionsverhalten im Therapieverlauf sichtbar gemacht werden.

Untersucht wurden drei Eltern-Kind-Dyaden mit unterschiedlichem Bildungshintergrund und unterschiedlichen Voraussetzungen: monolingual Deutsch, zusätzliche Erschwernisse in der Eltern-Kind-Interaktion, andere Erstsprache.

Es zeigten sich fallspezifische Schwerpunkte, Interaktionsverläufe und Beratungserfolge. Beratungsschwerpunkte blieben i. d. R. über einen längeren Zeitraum konstant. Eine wesentliche Herausforderung für Eltern CI-versorgter Kinder ist die Balance zwischen sensitiver Reaktion auf die Hörschädigung und angemessener Erhöhung sprachlicher Komplexität.
SARS-CoV-2-Infection in People Addicted to Illegal Drugs – Is There a
Protective Effect of Opioid Maintenance Treatment?
Authors: Kurzhals Simon , Schäfer Martin , Bonnet Udo , Isbruch Katrin , Kühnhold Stefan , Timm Jörg , Specka Michael , Scherbaum Norbert
Published: August 2024

Introduction People addicted to illegal drugs were discussed as a risk
group for SARS-CoV-2 infections, with increased susceptibility and a severe
course of infection.

Methods In this study, the frequency of SARS-CoV-2 infections of
drug-dependent persons admitted to inpatient detoxification treatment in five
psychiatric hospitals was determined by implementing routine polymerase chain
reaction (PCR)-testing at admission (9/2020) up to one year. Main
substance-related diagnosis, comorbid respiratory disease, housing situation,
and current opioid maintenance treatment (OMT) were documented. An age-matched
control group of psychiatric inpatients without dependence from illegal drugs
was established.

Results Data from 1675 patients (male 79.5%; mean age 39.5 years; opioid
dependence 81.5% homelessness; 2.4%; chronic respiratory disease 6.3%) were
included. Out of 1365 patients dependent on opioids, 50.2% were currently in
OMT. Six (3 female; mean age 40.3 years) patients tested positive for SARS-CoV-2
by PCR (0.36%), and none showed symptoms of COVID-19. All six were opioid
dependent, 5 currently not in OMT. In the control group, 11 out of 1811
inpatients tested positive (0.61%).

Discussion The rate of SARS-CoV-2-infections in persons with dependence on
illegal drugs was not increased compared to a control group of psychiatric
patients. OMT is presumably a protective factor, e. g. in the participating
cities, OMT facilities offered an easy access to vaccination programs. In
contrast, drug addicts in the USA were severely affected by the pandemic.
Differences between countries might partially be explained by social factors
such as the higher availability of OMT in Germany and a much lower frequency of
homelessness.
Clinical and Biochemical Features of Kids with COVID-19 Febrile Seizures during the Omicron Wave
Authors: Shi Yu , Miao Shijian , Shen Guomei , Fu Jin , Gao Xuan , Du Xiaonan , Huang Guoying , Zhou Shuizhen , Zhai Xiaowen
Published: August 2024

Objective Mild symptoms are the norm for children with coronavirus disease-2019 (COVID-19), but data on the Omicron form are few. One of the most frequent neurological symptoms of COVID-19 in children is febrile seizure (FS).

Methods Patients with FS who visited the pediatric fever clinic between December 6 and December 31, 2022, when the Omicron version of SARS-CoV-2 was the predominant strain, were included in this retrospective, single-center analysis.

Results Children who tested positive for COVID-19 had a 5.58% incidence of FSs. Compared to patients without COVID-19, a greater percentage of COVID-19 patients (29.5 vs. 7.5%, p < 0.01) experienced complex FSs. In the COVID-19-positive group, four cases were critically unwell and were admitted to the Intensive Care Unit (1.4 vs. 0%, p < 0.01), and the admission proportion was greater (18.9 vs. 1.9%, p < 0.01). The proportion of lactic acid and IL-6 increase was larger in the COVID-19-positive group (33.5 vs. 21.5%, 22.1 vs. 17.8%, p = 0.022, p = 0.006, respectively).

Conclusion Infections with COVID-19 in children have been linked to FSs in the Omicron era. To fully understand the neuropathogenesis of seizures in children with COVID-19, more research is required.
Survival Rate of High-Rise Syndrome Cases Using Animal Trauma Triage Score in Cats
Authors: İnal Kamil Serdar , Önyay Taylan , Ersoy Birsen Deniz Özbakır , Göl Melis , Kurban Elif Bağatır , Özak Ahmet , Yardımcı Cenk , Nisbet Hatice Özlem , Sağlam Kamil
Published: August 2024

Objective To assess the data of high-rise syndrome (HRS) cases and determine the relationship between Animal Trauma Triage Score (ATTS), height, injury profile, and survival rate of patients.

Study Design Retrospective study evaluating cats with HRS within a 4-year period.

Results A logistic regression analysis which included height, ground type, and ATTS variables was performed to predict survival rate of patients. Only ATTS was significant among these variables (p < 0.001) and each point increase in ATTS increased the nonsurvival by 0.46 times (95% confidence interval [CI]: 0.347–0.624). The receiver operating curve indicates that ATTS is good at predicting mortality (area under the curve: 0.857; 95% CI: 0.788–0.926; p < 0.001).

Conclusion The height of the fall, injury type, or ground type do not seem to be accurate in estimating the survival rate in HRS patients. Established scoring systems such as ATTS should be used to determine survival rates in future HRS studies.
A dialog between Sino-Western legal traditions: Yan Fu’s translation of “natural law” in Montesquieu’s The Spirit of Laws
Authors: Zhuang Chiyuan
Published: August 2024

As an integral component of legal culture, legal concepts possess distinct cultural characteristics. Translating legal concepts between different cultures to facilitate effective cultural exchange and mutual understanding poses a significant challenge for legal translators. This paper examines Yan Fu’s Chinese translation of “natural law”, a key concept in Montesquieu’s classic The Spirit of Laws, as a case study to analyze the connection between legal translation and cultural traditions in the socio-historical contexts of the early 20th century China. By analyzing Yan’s choice of words, the paper unveils how Yan Fu reinterpreted Western natural law from both religious and ethical perspectives, thereby creating a dynamic dialog between Sino-Western legal cultural traditions.
Improved regularity criteria for the MHD equations
Authors: Wang Weihua , Xu Shixia
Published: August 2024

In this paper, we establish new regularity criteria for the three-dimensional (3D) viscous incompressible magnetohydrodynamic (MHD) equations. It is proved that if the solution of the MHD equations satisfies u3∈Lp(0,T;Lq(R3)),j3∈Lr(0,T;Ls(R3)),2p+3q=1324,7213≤q≤∞;2r+3s=2,32<s≤∞ or u3∈Lp(0,T;Lq(R3)),w3∈Lr(0,T;Ls(R3)),2p+3q=1324,7213≤q≤∞;2r+3s=2,32<s≤∞, then the regularity of the solution on (0, T), where u3, j3 and ω3 are the third component of velocity u, current density ∇ × b and vorticity ∇ × u, respectively. These results give new improvements of regularity theory of weak solutions.
Heat kernel coefficients for massive gravity
Authors: Ferrero Renata , Fröb Markus B. , Lima William C. C.
Published: August 2024

We compute the heat kernel coefficients that are needed for the regularization and renormalization of massive gravity. Starting from the Stueckelberg action for massive gravity, we determine the propagators of the different fields (massive tensor, vector and scalar) in a general linear covariant gauge depending on four free gauge parameters. We then compute the non-minimal heat kernel coefficients for all the components of the scalar, vector and tensor sector, and employ these coefficients to regularize the propagators of all the different fields of massive gravity. We also study the massless limit and discuss the appearance of the van Dam–Veltman–Zakharov discontinuity. In the course of the computation, we derive new identities relating the heat kernel coefficients of different field sectors, both massive and massless.
Defect behavior during growth of heavily phosphorus doped Czochralski silicon crystals (II): Theoretical study
Authors: Sueoka Koji , Narushima Yasuhito , Torigoe Kazuhisa , Nonaka Naoya , Koga Koutaro , Ono Toshiaki , Horie Hiroshi , Hourai Masataka
Published: August 2024

Recent studies including our own report (I) have revealed that heavily phosphorus (P) doped Czochralski-silicon (HP-Cz-Si) exhibits peculiar defect behaviors during crystal growth. HP-Cz-Si crystals with a low resistivity of around 0.6 mΩ cm (P concentration of 1.3 × 1020 P cm−3) have interstitial-type stacking faults (SFs) and dislocations, which degrade device characteristics. The purpose of this paper is to clarify what causes the defect behavior in HP-Cz-Si through theoretical calculations. The thermal equilibrium concentrations of substitutional P (Ps), interstitial P (Pi), and (Ps)n-vacancy (V) clusters (n = 1−4) were determined by using density functional theory (DFT) calculations. The concentrations of Pi ([Pi]) and (Ps)nV ([(Ps)nV]) balanced with the given Ps concentration ([Ps]) were obtained as a function of the total P concentration ([P]) and the temperature. On the basis of the calculated results those can quantitatively explain our experimental results in the report (I), we propose a defect model that accurately represents HP-Cz-Si crystal growth. The main feature of the model is that the incorporated Pi atoms at the solid/liquid interface around [Pi] = 1017 Pi cm−3 cause the formation of SFs and dislocations during the HP-Cz-Si crystal growth with around [P] = 1020 P cm−3. Furthermore, DFT calculations were performed for Pi segregation on the SF and for the photoelectron spectra of P 1s measured by hard x-ray photoelectron spectroscopy to explain the other experimental results in the report (I).
Comparison of transport models in dense plasmas
Authors: Johnson Zachary A. , Silvestri Luciano G. , Petrov George M. , Stanton Liam G. , Murillo Michael S.
Published: August 2024

We compare a variety of models used for the calculation of transport coefficients in dense plasmas, including average-atom models, models based on kinetic theory, structure matching effective potentials, and pair-potential molecular dynamics. In particular, we focus on the parameter space investigated in the second charged-particle transport coefficient code comparison workshop [Stanek et al., Phys. Plasmas 31, 052104 (2024)]. Each model is based on the self-consistent output of our average-atom calculations. Ionic transport properties are generated from implicit electron pair matched molecular dynamics simulations, bypassing the need for either dynamical electron simulations or on-the-fly electronic structure calculations. These matched pair potentials are generated in a nonlinear way using a classical mapping procedure, further avoiding an expensive force-matching procedure. We compare these results with the density functional theory data presented at the workshop, as well as a set of widely used parametric models, which we have modified to enhance accuracy, especially at the low- and high-temperature extremes of the parameter space. We also detail the non-trivial statistical aspect of converging ionic transport coefficients.
Interaction between atmospheric pressure plasma jet and target
Authors: He Gaosheng , Liu Yuqing , He Feng , Miao Jinsong , Li Jingran , Zhang Yu , Gao Zhiliang , Wang Ruojue , Yan Xu , Ouyang Jiting
Published: August 2024

Interactions of floating potential on metal and dielectric targets with He atmospheric pressure plasma jet (APPJ) were studied in this paper. The APPJ is generated in a needle-ring corona-dielectric barrier discharge configuration, driven by a sinusoidal voltage. The characteristics of APPJ were assessed through electrical and optical examinations, and the time-average electrostatic voltage on the targets was measured using both contact and non-contact electrostatic voltmeters. It was found that both metal and dielectric targets can promote the jet development and speed up the jet velocity. During the negative half-cycle, the “plasma cluster” propagates from the target toward the ground electrode and then “merges” with the forward plasma jet, leading to a reversed development of jet. The two targets follow a similar pattern on the surface electrostatic voltage, that is, initially in a positive polarity whose amplitude first increases and then decreases and transits to negative polarity with an increase in the applied voltage. But there are also some minor differences between the two targets, e.g., the metallic target can change the discharge pattern and reduces the discharge current under certain conditions.
Competition among recombination pathways in single FAPbBr3 nanocrystals
Authors: Singha Prajit Kumar , Mukhopadhyay Tamoghna , Tarif Ejaj , Ali Fariyad , Datta Anindya
Published: August 2024

Single particle level microscopy of immobilized FAPbBr3 nanocrystals (NCs) has elucidated the involvement of different processes in their photoluminescence (PL) intermittency. Four different blinking patterns are observed in the data from more than 100 NCs. The dependence of PL decays on PL intensities brought out in fluorescence lifetime intensity distribution (FLID) plots is rationalized by the interplay of exciton- and trion-mediated recombinations along with hot carrier (HC) trapping. The high intensity-long lifetime component is attributed to neutral exciton recombination, the low intensity-short lifetime component is attributed to trion assisted recombination, and the low intensity-long lifetime component is attributed to hot carrier recombination. Change-point analysis (CPA) of the PL blinking data reveals the involvement of multiple intermediate states. Truncated power law distribution is found to be more appropriate than power law and lognormal distribution for on and off events. Probability distributions of PL trajectories of single NCs are obtained for two different excitation fluences and wavelengths (λex = 400, 440 nm). Trapping rate (kT) prevails at higher power densities for both excitation wavelengths. From a careful analysis of the FLID and probability distributions, it is concluded that there is competition between the HC and trion assisted blinking pathways and that the contribution of these mechanisms varies with excitation wavelength as well as fluence.
Trichel pulses and ionic wind in a tube-plate air gap
Authors: Ning Wenjun , Shen Xueming , Yang Shuai , Zhang Yue , Huang Xiaolong , Ren Junwen , Jia Shenli
Published: August 2024

Trichel pulses could be observed in negative corona that was typically generated in a needle-plate gas gap. In the present work, we studied the properties and discharge mechanism of the Trichel pulse produced by a tube-plate structure, and some distinguished features were observed by both modeling and experiments. A classic three-species fluid discharge model was adopted to study the discharge dynamics and coupling with a hydrodynamic model to solve for the induced flow field (ionic wind). The model was validated with experimental observations and measurement. Trichel pulses were observed in the tube-plane geometry, but with higher sustaining voltage (in the order of −10 kV), higher peak current (in the order of 10 mA), and lower repeating frequency (in the order of 10 kHz) than these in the corresponding needle-plate corona system (in the order of –1 kV, 1 mA, and 100 kHz, respectively). Due to the electrostatic force, the negative corona around the tube orifice would deflect outward. A strong perturbation to the neutral gas associated with the corona was observed in the experiment and predicted by simulation. Ambient air around the tube orifice would be inhaled into the tube and then exhausted from the other end with the velocity of about 1.9 m/s. Slightly temperature rise at the tube tip by about 40 K was predicted by the model. Effects of the voltage amplitude and the tube diameter were then parametrically discussed. Results in the present work might contribute to an extended understanding of discharge mechanism of Trichel pulses in negative corona.
New lower bounds on the radius of spatial analyticity for the higher order nonlinear dispersive equation on the real line
Authors: Zhang Zaiyun , Deng Youjun , Li Xinping
Published: August 2024

In this paper, benefited some ideas of Wang [J. Geom. Anal. 33, 18 (2023)] and Dufera et al. [J. Math. Anal. Appl. 509, 126001 (2022)], we investigate persistence of spatial analyticity for solution of the higher order nonlinear dispersive equation with the initial data in modified Gevrey space. More precisely, using the contraction mapping principle, the bilinear estimate as well as approximate conservation law, we establish the persistence of the radius of spatial analyticity till some time δ. Then, given initial data that is analytic with fixed radius σ0, we obtain asymptotic lower bound σ(t)≥c|t|−12, for large time t ≥ δ. This result improves earlier ones in the literatures, such as Zhang et al. [Discrete Contin. Dyn. Syst. B 29, 937–970 (2024)], Huang–Wang [J. Differ. Equations 266, 5278–5317 (2019)], Liu–Wang [Nonlinear Differ. Equations Appl. 29, 57 (2022)], Wang [J. Geom. Anal. 33, 18 (2023)] and Selberg–Tesfahun [Ann. Henri Poincaré 18, 3553–3564 (2017)].
Design of eco-friendly antifreeze peptides as novel inhibitors of gas-hydration kinetics
Authors: Zhang Nan , Zhu Ying , Li Yan-Nan , Zhang Li-Rong , Zhang Feng-Shou , Liu Jun-Jie
Published: August 2024

In this study, peptides designed using fragments of an antifreeze protein (AFP) from the freeze-tolerant insect Tenebrio molitor, TmAFP, were evaluated as inhibitors of clathrate hydrate formation. It was found that these peptides exhibit inhibitory effects by both direct and indirect mechanisms. The direct mechanism involves the displacement of methane molecules by hydrophobic methyl groups from threonine residues, preventing their diffusion to the hydrate surface. The indirect mechanism is characterized by the formation of cylindrical gas bubbles, the morphology of which reduces the pressure difference at the bubble interface, thereby slowing methane transport. The transfer of methane to the hydrate interface is primarily dominated by gas bubbles in the presence of antifreeze peptides. Spherical bubbles facilitate methane migration and potentially accelerate hydrate formation; conversely, the promotion of a cylindrical bubble morphology by two of the designed systems was found to mitigate this effect, leading to slower methane transport and reduced hydrate growth. These findings provide valuable guidance for the design of effective peptide-based inhibitors of natural-gas hydrate formation with potential applications in the energy and environmental sectors.
Resolvent analysis for predicting energetic structures in the far wake of a wind turbine
Authors: Feng Dachuan , Gupta Vikrant , Li Larry K.B. , Wan Minping
Published: August 2024

A thorough understanding of the energetic flow structures that form in the far wake of a wind turbine is essential for accurate turbine wake modeling and wind farm performance estimation. We use resolvent analysis to predict such flow structures for a turbine operating in a neutral atmospheric boundary layer and validate our results against data-driven modes extracted through spectral proper orthogonal decomposition. The forcing and response modes calculated from resolvent analysis reveal the upstream forcing locations that are most influential in generating turbulent kinetic energy (TKE) in the far wake. Additionally, resolvent analysis shows the important role of transverse forcing and contribution of the non-modal Orr mechanism in TKE generation. The resolvent analysis method requires only the mean wake velocity and eddy viscosity profiles as inputs but can capture the energetic modes and TKE spectra in the far wake. In this specific application, the resolvent analysis method approximates the wake to be axisymmetric, which suggests that it can be paired with engineering wake models. Overall this study demonstrates the use of resolvent analysis as a viable tool for estimating TKE and for uncovering the mechanism of TKE generation.
Digital signal processing techniques for noise characterization of lasers and optical frequency combs: A tutorial
Authors: Riebesehl Jasper , Heebøll Holger R. , Razumov Aleksandr , Galili Michael , Zibar Darko
Published: August 2024

Performing noise characterizations of lasers and optical frequency combs on sampled data offers numerous advantages compared to analog measurement techniques. One of the main advantages is that the measurement setup is greatly simplified. Only a balanced detector followed by an analog-to-digital converter is needed, allowing all the complexity to be moved to the digital domain. Secondly, near-optimal phase estimators are efficiently implementable, providing accurate phase noise estimation in the presence of measurement noise. Finally, joint processing of multiple comb lines is feasible, enabling the computation of the phase noise correlation matrix, which includes all information about the phase noise of the optical frequency comb. This tutorial introduces a framework based on digital signal processing for phase noise characterization of lasers and optical frequency combs. The framework is based on the extended Kalman filter (EKF) and automatic differentiation. The EKF is a near-optimal estimator of the optical phase in the presence of measurement noise, making it very suitable for phase noise measurements. Automatic differentiation is key to efficiently optimizing many parameters entering the EKF framework. More specifically, the combination of EKF and automatic differentiation enables the efficient optimization of phase noise measurement for optical frequency combs with arbitrarily complex noise dynamics that may include many free parameters. We show the framework’s efficacy through simulations and experimental data, showcasing its application across various comb types and in dual-comb measurements, highlighting its accuracy and versatility. Finally, we discuss its capability for digital phase noise compensation, which is highly relevant to free-running dual-comb spectroscopy applications.
Generation of large-scale magnetic-vortex structures in stratified magnetized plasma by a small-scale force
Authors: Kopp M. I. , Yanovsky V. V.
Published: August 2024

In this study, within the framework of electron magnetohydrodynamics, taking into account thermomagnetic phenomena, we obtained a new large-scale instability of the α-effect type, which ensures the generation of large-scale vortex and magnetic fields. This instability occurs in a flat layer of temperature-stratified plasma under the influence of an external uniform magnetic field inclined relative to the layer, combined with a small-scale external force having zero helicity. The external force is presented as a source of small-scale oscillations in the speed of electrons with a low Reynolds number R≪1. The presence of a small parameter in the system allowed us to apply the method of multiscale asymptotic expansions to derive nonlinear equations for vortex and magnetic disturbances. These equations were obtained in third-order Reynolds number. Using solutions for the velocity field in zero order in Reynolds number, we determined the average helicity H=v0·rotv0¯ and its relation to the α-effect. A necessary condition for the generation of average helicity in stratified magnetized plasma is the inclined orientation of the external magnetic field and the presence of a small-scale force. A new effect related to the influence of thermal force (the Nernst effect) on large-scale instability is discussed. It is shown that an increase in the Nernst parameter leads to a decrease in the amplification factor α and thereby prevents the development of large-scale instability. With the help of numerical analysis, stationary solutions to the vortex and magnetic dynamo equations in the form of localized structures like nonlinear waves of the Beltrami were obtained.
Effect of sequential N ion implantation in the formation of a shallow Mg-implanted p-type GaN layer
Authors: Uzuhashi Jun , Chen Jun , Tanaka Ryo , Takashima Shinya , Edo Masaharu , Ohkubo Tadakatsu , Sekiguchi Takashi
Published: August 2024

An area-selectable Mg doping via ion implantation (I/I) is essential to realize gallium nitride (GaN) based power switching devices. Conventional post-implantation annealing forms considerable defects in the GaN, resulting in extremely low activation efficiency. The recent invention of ultrahigh-pressure annealing (UHPA) has substantially improved the p-type activation efficiency; however, the UHPA causes an unexpected Mg diffusion. Thus, both annealing processes resulted in a much lower Mg concentration in the GaN matrix than the Mg dose. In this study, the effect of a sequential N I/I for p-type Mg-implanted GaN was investigated by the correlative cathodoluminescence, transfer length method, scanning transmission electron microscopy, and atom probe tomography (APT) analyses. APT results have revealed that the sequential N I/I can successfully maintain the Mg concentration in the GaN matrix in the higher range of 1018 cm−3 or more. Our investigation suggests that sequential N I/I is a promising technique to maintain the Mg concentration higher and improve the p-type activation efficiency.
Machine learning based unfolding of x-ray spectra from filter stack spectrometer data
Authors: Alvarado Alvarez M. , Wolfe B. T. , Wong C.-S. , Broughton D. P. , Huang C.-K. , Reinovsky R. E. , Wang Z. , Batha S. H.
Published: August 2024

We demonstrate the application of neural networks to perform x-ray spectra unfolding from data collected by filter stack spectrometers. A filter stack spectrometer consists of a series of filter-detector pairs, where the detectors behind each filter measure the energy deposition through each layer as photo-stimulated luminescence (PSL). The network is trained on synthetic data, assuming x-rays of energies <1 MeV and of two different distribution functions (Maxwellian and Gaussian) and the corresponding measured PSL values obtained from five different filter stack spectrometer designs. Predicted unfolds of single distributions are near identical reproductions of the ground truth spectra, with differences in the values lower than 20% at the higher energy end in some cases. The neural network has also demonstrated robustness to experimental measurement errors of <5% and some capability of performing unfolds for linear combinations of the two distributions without previous training. The network can perform unfolds at rates >1 Hz, ideal for application to some high-repetition-rate systems.
Magnetometry in a diamond anvil cell using nitrogen vacancy centers in a nanodiamond ensemble
Authors: Shelton David P. , Cabriales Waldo , Salamat Ashkan
Published: August 2024

The emerging field of optical magnetometry utilizing negative-charged nitrogen vacancy (NV−) centers provides a highly sensitive lab bench technique for spatially resolved physical property measurements. Their implementation in high pressure diamond anvil cell (DAC) environments will become common as other techniques are often limited due to the spatial constraints of the sample chamber. Apparatus and techniques are described here permitting for more general use of magnetic field measurements inside a DAC using continuous wave optical detected magnetic resonance in NV− centers in a layer of nanodiamonds. A microstrip antenna delivers a uniform microwave field to the DAC and is compatible with simple metal gaskets, and the sensor layer of deposited nanodiamonds allows for simple determination of the magnetic field magnitude for B in the 1–100 G range. The ferromagnetic transition in iron at 18 GPa is measured with the apparatus, along with its hysteretic response.
Off-center impact dynamics of a droplet against hydrophobic surfaces
Authors: Gao Shu-Rong , Liu Zhe , Shi Shi-Hua , Yang Yan-Ru , Wang Xiao-Dong
Published: August 2024

When a droplet off-center impacts a macro-ridge, it may split into two asymmetric fragments, i.e., the smaller part (SP) and larger part (LP), which then exhibit asymmetric spreading and receding phenomena. Using lattice Boltzmann method simulations, the dynamics of a droplet off-center impacting a hydrophobic surface are explored for the first time. Influences of the off-center distance, the impact Weber number, and the surface wettability on the impact outcomes and the contact time are elucidated, and the impact regime is established. Six impact outcomes are discovered as off-center distance changes, which are dependent on the interaction force between the droplet and the surface. The effect of the off-center distance and the Weber numbers on the spreading and the receding dynamics of the SP is more obvious than that of the LP, due to the fact that adhesion of the ridge on the LP can be negligible compared to the inertial force and the surface tension. The contact time is closely related to the impact outcomes, that is, when the impact outcome is type 1 (SP and LP separate rebound), the contact time can be significantly reduced compared with that on the flat hydrophobic surface, due to the fact that the ridge can reduce the asymmetry of a liquid film and the receding distance in this case; while when the impact outcome is type 6 (SP and LP completely coalescence and rebound), the contact time cannot be reduced. This work extends the fundamental knowledge of off-center impact and provides inspiration for the efficient reduction in the contact time.
Indication of the measuring method for accurately determining the critical current and n value in superconducting wires and tapes used in superconducting coils
Authors: Gajda Daniel , Zaleski Andrzej J. , Babij Michał , Rindfleisch Matt A.
Published: August 2024

In our article, we show the n value determined from measurements using the magnetic field sweep method (curves of E from B/Bc) and the current sweep method (curves of E from I/Ic). The results from these two methods allowed for a scientific n value analysis. Moreover, measurements using these two methods allow for a better understanding of the behavior of superconducting wires after the transition from the superconducting state to the normal (resistive) state. Measurements were made for the NbTi wire at 4.2 K, MgB2 at the temperature range from 4.2 to 30 K, and high-temperature superconducting tape at 77 K. The magnetic field sweep method results show that the n value has a constant value independent of an increase in the magnetic field, number of filaments, type of boron, diameter of the wire, and small amount of the dopant. Moreover, research studies point out that the n value in the magnetic field sweep method depends on the type of superconductor material, a large amount of doping at high temperatures, and the low density of pinning centers. Based on the results obtained, it can be indicated that each superconducting material will have a constant n value. Measurements carried out using the current sweep method showed that the n value decreases significantly with an increase in the magnetic field. Moreover, research studies have shown that the n value depends on the number of filaments, type of boron, dopant, wire diameter, and temperature. On this basis, it can be indicated that the n value for the current sweep method depends on the morphology and structure of the superconducting wires. In addition, based on the samples measured in this research, the current sweep method allows for higher n values than the magnetic field sweep method in low magnetic fields. However, the magnetic field sweep method allows obtaining higher n values than the current sweep method in middle and high magnetic fields.
High-efficiency and precision gas extraction in intelligent mining faces: Application of a comprehensive three-dimensional extraction system
Authors: Lu Zhuang , Wang Liang , Fu Shenguang , Chu Peng , Zhu Zibin , Wang Hao , Zhao Changxin , Wu Songwei , Cheng Yuanping
Published: August 2024

As intelligent mining operations evolve, stringent standards for gas management and extraction are imperative. To mitigate the risks associated with coal and gas outburst and to prevent gas concentration from exceeding safe limits, a comprehensive three-dimensional gas extraction system is introduced. This method, exemplified by the 1075 intelligent working face at the Yangliu coal mine, integrates temporal and spatial considerations for comprehensive extraction. Utilizing COMSOL and UDEC simulations, the extraction parameters for both pre-extraction and mid-mining extraction have been meticulously optimized. The optimal strategy involves boreholes with a diameter of 113 mm, spaced 3 m apart, and an initial negative pressure of 31 kPa, which is subsequently reduced to 13 kPa as gas levels decrease. The positioning of directional high-level boreholes is determined by the fracture zone distribution in the goaf's overlying strata, placed 19–25 m above the roof and 0–65 m from the return airway. Directional interception boreholes are optimally located 54–73 m above the roof. Surface wells are strategically positioned 15 m above the roof, with a horizontal distance of 30–65 m from the return airway. After extraction of the system, the maximum gas concentrations recorded in the return airway and the upper corner are 0.26% and 0.27%, respectively. The average daily production reached 5258 t, nearly doubling the overall efficiency. This gas extraction technique not only enhances the efficiency of intelligent mining operations but also serves as a valuable reference for future research in the field.
Deep brain temporally interfering magnetic stimulation via parametric characterized spatial array
Authors: Fang Xiao , Wang Shaolong , Luo Yaoyao , Lin Yu , Yang Wenlong , Zhang Tao
Published: August 2024

Transcranial magnetic stimulation (TMS) shows great research potential in human neuroscience. However, when it comes to stimulating deeper brain regions, traditional TMS is restricted by the balance between stimulation focalization and stimulation depth. Temporal interference (TI) stimulation offers a new thought to solve the problem. In this paper, we first discussed the principles of TI-TMS and then established the theoretical model of TI-TMS using the head-surrounded spatial array. Next, we specially designed the parametric characterized spatial array (PCS array) suitable for TI-TMS. The proposed PCS array contains eight special-shaped coils that constitute four sets of difference frequency stimulation pairs and are placed around the human head. Distribution characteristics of the temporally interfering electric fields (E-fields) including stimulation intensity, stimulation focalizations on 1D, 2D, and 3D levels, and attenuation ratios in X, Y, and Z directions were obtained using the finite element analysis method. Our results indicate that the proposed PCS array could form an obvious focusing area with strong stimulation at a stimulation depth of 5 cm below the human scalp while the superficial region is under weak stimulation, which effectively combines the advantages of TMS and TI stimulation. Compared to the traditional TMS systems, the TI-TMS with PCS array can realize selective and focalized stimulation in the deep brain and increase the average attenuation ratio of the induced temporally interfering E-fields by more than 1.93 times. A real human head model containing gray matter was also employed in this paper to verify our results.
Persistence of large-scale coherent structures in a turbulent pipe flow through an improved lattice Boltzmann approach
Authors: Magacho B. , Moriconi L. , Loureiro J. B. R.
Published: August 2024

We simulated a turbulent pipe flow within the lattice Boltzmann method using a multiple-relaxation-time collision operator with Maxwell–Boltzmann equilibrium distribution expanded, for the sake of a more accurate description, up to the sixth order in Hermite polynomials. The moderately turbulent flow (Reτ≈181.3) is able to reproduce up to the fourth statistical moment with great accuracy compared with other numerical schemes and with experimental data. A coherent structure identification was performed based on the most energetic streamwise turbulent mode, which revealed a surprising memory effect related to the large-scale forcing scheme that triggered the pipe's turbulent state. We observe that the existence of large-scale motions that are out of the pipe's stationary regime does not affect the flow's detailed single-point statistical features. Furthermore, the transitions between the coherent structures of different topological modes were analyzed as a stochastic process. We find that for finely resolved data, the transitions are effectively Markovian, but for larger decimation time lags, due to topological mode degeneracy, non-Markovian behavior emerges, in agreement with previous experimental studies.
Solution-based iron doping of solvothermally grown 2D hexagonal bismuth telluride
Authors: Marcus Gabriel E. , Carlson Timothy W. , Swathi Kadaba , Carroll David
Published: August 2024

In this work, we examine the formation of iron-based magnetic domains on two-dimensional (2D) single-crystal bismuth telluride plates. Using solvothermal chemical methods, 2D bismuth telluride (Bi2Te3) single crystalline nanoplates were reacted with iron salts (FeCl2) to achieve electrical doping. The use of a reducing agent [L(+)-ascorbic acid] along with FeCl2 resulted in homogeneous dispersion of iron across the crystal, whereas non-reduced iron doping achieved edge growth of iron/iron oxide nanoparticles. High-resolution analytical electron microscopy was used to examine the iron nanoparticle accumulation and morphology at nanoplate edges for non-reduced materials and iron dispersions within the crystals in the case of reduction. Our analysis revealed little variation in the atomic uptake of iron in any form over a range of solution-dopant concentrations. However, structural analysis and transport measurements clearly indicate the tendency of the dopant nanoparticles to oxidize quickly. The Seebeck coefficient and power factor also express modifications with exposure to oxidation, providing an indirect probe of the dopant modification to the host Bi2Te3’s electronic properties. Importantly, however, magnetic force microscopy images show a distinct difference in the formation of magnetic phases with and without the use of reducing agents during iron doping. This suggests that oxidation post-doping does not form magnetic phases, whereas oxidation during the doping process is suitable for obtaining magnetically doped Bi2Te3 nanocrystals.