bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure, bonding and electronic characteristics of amorphous Se
Authors: Qiao Chong , Chen Lanli , Gu Rongchuan , Liu Bin , Wang Shengzhao , Wang Songyou , Wang Cai-Zhuang , Ho Kai-Ming , Xu Ming , Miao Xiangshui
Published: February 2024

Se atoms present strong but short-range bonding interactions, leading to amorphous Se forming chain structures.
Microstrain effects of laser-ablated Au nanoparticles in enhancing CZTS-based 1 Sun photodetector devices
Authors: Gezgin Serap Yiğit , Belaid Walid , Kabatas Mohamed A. Basyooni-M. , Eker Yasin Ramazan , Kilic Hamdi Şükür
Published: February 2024

A plasmonic 1 Sun photodetector under the influence of Au nanoparticles with fast photodetection capability.
Quenching of bacteriochlorophyll a triplet state by carotenoids in the chlorosome baseplate of green bacterium Chloroflexus aurantiacus
Authors: Yakovlev Andrei G. , Taisova Alexandra S.
Published: February 2024

Combination of BChl aT quenching by Car and short lifetime of BChl a* provides an excellent photoprotection of the baseplate in C. aurantiacus chlorosomes.
Porphyrin(2.1.2.1) organopalladium complexes as efficient singlet oxygen sensitizers
Authors: Lv Xiaojuan , Dong Yuting , Wu Jinrong , Jiang Tao , Chen Feng , Zhang Tao , Qiu Fengxian , Xue Songlin
Published: February 2024

Non-planar and non-aromatic porphyrin(2.1.2.1) organopalladium complexes show singlet oxygen quantum yields as high as 56%, slightly lower than that of Ru(bpy)3Cl2 and some clinically evaluated porphyrinoid 1O2 sensitizers.
Sustainable synthesis of thiosulfonates and disulfides by molybdenum-catalyzed selective oxidation of thiols
Authors: Zhou Zhibin , Xu Hao , Ma Jiamin , Zeng Xianghua , Wei Yongge
Published: February 2024

We report a polyoxomolybdate ([N(n-Bu)4]4Mo8O26) for the selective oxidation of thiols to thiosulfonates and disulfides with H2O2 and air as the oxidant, respectively.
In situelectronic redistribution of NiCoZnP/NF heterostructureviaFe-doping for boosting hydrazine oxidation and hydrogen evolution
Authors: Shi Tongtong , Gao Bo , Meng Haoyu , Fu Yumo , Kong Delong , Ren Penghui , Fu Haiyang , Feng Zhongbao
Published: February 2024

A Fe-doped Ni2P-Co2P-Zn3P2heterogeneous electrocatalyst with a nanoneedle-assembled nanosphere structure and abundant defects was fabricated on Ni foam (Fe-NiCoZnP/NF). Fe-NiCoZnP/NF shows enhanced electrocatalytic activity and stability for HER and HzOR.
Enhancing the photocatalytic elimination of acephate residues using Ni0 doped and diatomite-supported NiO: optimization, pathway, and toxicity
Authors: Othman Sarah I. , Alfassam Haifa E. , Alqhtani Haifa A. , Al-Waili Maha A. , Alharbi Hanan Mualla , Allam Ahmed A. , Abukhadra Mostafa R.
Published: February 2024

NiO nanoparticles were synthesized and modified with Ni0 in the form of Ni/NiO blend and supported on a porous diatomite substrate, forming hybrid structures of NiO/D and Ni@NiO/D with enhanced photocatalytic performances.
Efficient and metal-free synthesis of 2-aroyl 7-azaindoles via thermally induced denitrogenative intramolecular annulation of 1,2,3,4-tetrazolopyridines
Authors: Chamakiya Chirag A. , Chothani Savankumar R. , Joshi Rupal J. , Bhalodia Jasmin , Ambasana Mrunal A. , Bapodra Atul H. , Kapuriya Naval
Published: February 2024

Dowtherm-A mediated facile synthesis of 2-aroyl 7-azaindoles via a hetereoannulation strategy.
Augmented LT codes over binary extension fields with increased ratio of full‐degree columns
Authors: Jiang Changyue , Cui Jingsong , Li Jiawei , Guo Chi
Published: February 2024

This letter proposes an augmented scheme of LT codes to improve the decoding success rate. The method involves substituting the 1‐s in full‐degree columns of the generator matrix of conventional LT codes with binary extension field elements and simultaneously increasing the ratio of full‐degree columns in the ideal soliton distribution. For non‐full‐degree columns, we retain the nonzero elements as 1‐s in the conventional LT codes generator matrix to preserve computational efficiency. Compared to conventional LT codes, the proposed method enhances the linear independence of the generator matrix, leading to a higher decoding success rate with minimal data packets. Experimental results demonstrate the effectiveness of the method at improving the performance of LT codes, with close to 100% decoding success rate achieved with around 5% data redundancy.
Identifying exploitable memory objects for out‐of‐bound write vulnerabilities
Authors: Li Runhao , Zhang Bin , Tang Chaojing
Published: February 2024

Exploiting an out‐of‐bounds write vulnerability in general‐purpose applications has become a current research focus. Given the large scale of code in programs, selecting appropriate memory objects for exploitation is challenging. This letter proposes a corrupted data propagation‐guided fuzzing method. By tracking the propagation process of corrupted data among memory objects, a multi‐level fuzzing schedule is proposed to search the execution paths. Experimental results show that this proposed method, EMOFuzz, can effectively identify exploitable objects under various overflow lengths, significantly enhancing the efficiency of exploitability analysis.
Joint prototype and coefficient prediction for 3D instance segmentation
Authors: Royen Remco , Denis Leon , Munteanu Adrian
Published: February 2024

3D instance segmentation is crucial for applications demanding comprehensive 3D scene understanding. Here, a novel method is introduced that simultaneously learns coefficients and prototypes. Employing an overcomplete sampling strategy, the method produces an overcomplete set of instance predictions, from which the optimal ones are selected through a Non‐Maximum Suppression (NMS) algorithm during inference. The obtained prototypes are visualizable and interpretable. The method demonstrates superior performance on S3DIS‐blocks, consistently outperforming existing methods in mRec and mPrec. Moreover, it operates 32.9% faster than the state‐of‐the‐art. Notably, with only 0.8% of the total inference time, the method exhibits an over 20‐fold reduction in the variance of inference time compared to existing methods. These attributes render the method well‐suited for practical applications requiring both rapid inference and high reliability.
MaglevMotor: Design and optimisation of a novel hybrid linear actuator for 6 degrees of freedom rail‐passive Maglev carrier
Authors: Bozkurt Ahmet Fevzi , Erkan Kadir
Published: February 2024

A novel levitating hybrid linear actuator is proposed for magnetically levitated carrier systems. This hybrid linear actuator, “MaglevMotor”, is capable to levitate itself under the passive rail and thrusts itself in a single longitudinal direction. The proposed structure aims to reduce complexity by minimising the necessary number of components, resulting in simplified geometry, improved assembly convenience, and decreased manufacturing tolerances. The MaglevMotor is optimised in multi‐physics aspect. Optimisation objectives are maximising thrust force, minimising total mass and minimising mechanical deformation of yoke with constraints of a user defined magnetic flux density (B) in yoke and zero power condition for specific air gap value. The authors present pre‐optimisation studies, optimisation results and final MaglevMotor designs step by step. By utilising three of the MaglevMotors units, the carrier is able to achieve motion in six degrees of freedom. The carrier's performance targets, including a 0.2 G acceleration, a total mass of less than 10 kg, and a 5 mm levitation air gap, have been both attained and validated through corresponding experiments.
Infrared multi‐target detection and tracking in dense urban traffic scenes
Authors: Zha Chaoneng , Luo Suyun , Xu Xinhao
Published: February 2024

Infrared object detection and tracking in dense urban traffic remain a challenge due to factors such as low contrast, small intra‐class differences, and frequent false positives and negatives. To overcome these, the authors introduce YOLO‐IR, an algorithm based on the enhanced YOLOv8s, and YOLO‐DeepOC‐IR, a comprehensive infrared multi‐object tracking method for urban traffic, integrating both detection and tracking. During preprocessing, three infrared image enhancement techniques, local contrast multi‐scale enhancement, non‐local means, and contrast limited adaptive histogram equalization, are applied for better reliability in dense scenes. To further improve the performance, the original YOLOv8s backbone is replaced with MobileVITv3 to enhance detection accuracy and robustness. This infrared feature extraction module, incorporated into the detector, combines canny edge detection, Gabor filtering, and open operation layers, significantly boosting object detection in infrared imagery. The tracker's feature processing capabilities are improved using the learned arrangements of three patch codes descriptor and locality‐sensitive hashing for feature extraction and matching. Experimental results on FLIR ADAS v2 and InfiRay datasets indicate superior performance of this method, achieving 78.6% mAP and 151.1 FPS in detection, and up to 80.8% moving object tracking accuracy, 78.6% identification F1 score, and 62.1% higher order tracking accuracy in multi‐object tracking.
A lightweight waxberry fruit detection model based on YOLOv5
Authors: Yang ChengYu , Liu Jun , He JianTing
Published: February 2024

In order to solve the safety and efficiency problems in the picking process of Waxberry, the slow speed and low precision of high‐density Waxberry target detection under a complex background were studied. A lightweight Waxberry target detection algorithm based on YOLOv5 is studied. In this study, C3‐Faster1 and C3‐Faster2 modules are proposed, which are located in the backbone and neck of the network: C3‐Faster1 can improve the model speed with a simple structure; C3‐Faster2 integrates the context attention mechanism and transform module based on C3‐Faster1 to make the network pay attention to the information of Waxberry image context and expand the channel receptive field. A new pyramid module, SPPFCSPC, is proposed to expand the sensing field and improve the accuracy of boundary detection. It also combines the Coordinate Attention (CA) and Dyhead dynamic detection head to suppress useless information and enhance the detection ability of small targets. Compared to YOLOv4, YOLOv7, and YOLOv8, mean accuracy percentage (mAP) improved by 5.7%, 9.4%, 8.3%. Compared to the base YOLOv5 model, mAP has improved from 86.5% to 91.9%, running on 2 GB Jeston nano, and the improved model is 5.03 frames per second (FPS) faster than YOLOv5. Experiments show that the designed module is more effective in Waxberry detection tasks.
A compact single‐layer reflective metasurface for high‐efficiency polarisation conversion applications in C and X bands
Authors: Raziul Islam Kd. M. , Rahimian Ardavan , Machado Gabriel G. , Babar Abbasi Muhammad Ali , Cheema Adnan Ahmad , Meenan Brian J.
Published: February 2024

The authors design and experimentally analyse an anisotropic metasurface for the simultaneous conversions of linear cross and circular polarisations in the C and partial X bands. The proposed compact structure utilises a dual‐cut square‐ring resonator and a square patch on an FR4 substrate above a ground plane. The full‐wave simulations exhibit over 92% efficiency in cross‐conversion over a fractional bandwidth (BW) of 52.3%. The proposed metasurface efficiently converts linear to circular polarisation in two different bands, achieving left‐hand circularly polarised and right‐hand circularly polarised efficiencies exceeding 93% and 89%, respectively. The compact unit‐cell with dimension 0.22λ × 0.22λ attains stable polarisation transformation efficiency rates exceeding 80% up to 40° incident angles. The design is adaptable for efficient wide BW across both lower and higher (millimetre‐wave) frequencies through scaling. A prototype of the proposed polarisation converter (PC) was realised and validated effectively in measurements, aligning well with simulations. This PC features a novel and simple structure with multifunctional wideband operation, stable incident angle output, polarisation insensitivity, and scalability, making it an efficient front‐end for various radio frequency applications, including polarisation control and polarisation transformers.
Point‐to‐point intensity modulation and direct detection flexible transceivers incorporating cascaded inverse fast fourier transform/fast fourier transform‐based multi‐channel aggregation/de‐aggregation techniques
Authors: Chen Lin , Wang Xinyu , Jin Wei , Huang Xiaoyu , Yang Gang , Jiang Mingyang , Tang Jianming
Published: February 2024

Point‐to‐point (P2P) flexible transceivers are the key technical enabler to cost‐effectively offer fast, dynamic, and ‘just‐the‐right‐size’ ultra‐dense P2P connectivity for various applications including remote equipment control and distributed fibre networks. However, existing flexible transceivers originally designed for hub‐and‐spoke traffic patterns are sub‐optimal. To effectively address such technical issue, a P2P flexible transceiver incorporating a cascaded inverse fast fourier transform/fast fourier transform‐based multi‐channel aggregation/de‐aggregation technique and analogue in‐phase and quadrature (IQ) mixers is proposed and numerically evaluated in a 56Gbps@20 km intensity modulation and direct detection transmission system. The proposed P2P flexible transceivers not only support adaptive and flexible variations in both channel count and channel line rate but also offer additional physical layer network security.
Research on harmonic generation principle of series‐connected multi‐pulse rectifiers and optimization design method for main transformers
Authors: Li Quanhui , Gao Lei , Meng Fangang
Published: February 2024

To improve the power density of series‐connected multi‐pulse rectifiers (MPRs), the harmonic generation principle is studied and the optimization design method for main transformers is proposed. According to the topology of series‐connected 18‐pulse rectifier, its operation waveforms are analysed, and the Fourier series of the waveforms is obtained. Based on the operation waveforms and its Fourier analysis, the principle for harmonic generation of the rectifier is researched, and the phenomenon of autotransformer cannot be applied to series‐connected MPRs is researched. According to the characteristics of the transformer, its vector graphics are analysed. Based on the vector graphics, the optimal structure of the transformer with the highest power density is obtained. The results show that the premise of the normal operation of series‐connected MPRs is the potential difference between the neutral points of different secondary windings, and only isolation/semi‐isolation transformers meet the requirement; the kilovolt‐ampere (kVA) rating of the optimal isolation type transformer is 104.6% pu, and the kVA rating of the optimal semi‐isolation type transformer is about 71.23% pu.
Robust adaptive backstepping control of H‐bridge inverter based on type‐2 fuzzy optimization of parameters
Authors: Azarinfar Hossein , Khosravi Mohsen , Soroush Morteza Zangeneh , Ghamari Seyyed Morteza
Published: February 2024

A type‐2 fuzzy logic‐based adaptive backstepping control (T2FABSC) approach is designed for an H‐bridge inverter. This inverter has an LC filter to decrease the level of total harmonic distortion (THD) that can affect the efficiency of the system. Reduction of THD and stability insurance of the filter are challenging trade‐offs, tackled here by a controller design. The performance, however, is not suitable for actual applications under a wider range of disturbances, and the parameters need to be adjusted once more for more dependable operations. Backstepping control is given a Lyapunov definition‐based adaptive mechanism that can improve this scheme's stability and robustness in the face of numerous disturbances. Additionally, the system is viewed as a “Black box” without the need for a precise mathematical model, which might lead to a lighter computing burden and simpler implementation. Moreover, a fuzzy type‐2 structure is adopted that can optimize the gains of the adaptive Backstepping controller (ABSC) in challenging conditions. The antlion optimization algorithm is employed to optimize the parameters of the membership functions in the fuzzy system, hence improving the performance of the controller. In addition, compared with different optimization algorithms, it can more quickly and accurately locate the best solutions. Finally, the findings of both the simulations and the experimental outputs are examined, proving the T2FABSC's significant robustness and faster dynamics in a variety of challenging circumstances.
The impact of spot‐size on single‐photon avalanche diode timing‐jitter and quantum key distribution
Authors: Lee Alexandra , Castillo Alfonso Tello , Whitehill Craig , Donaldson Ross
Published: February 2024

In free‐space implementations of Quantum key distribution (QKD), the wide adoption of near‐Infrared wavelengths has led to the common use of silicon single‐photon avalanche diodes (Si‐SPAD) for receiver systems. While the impacts of some SPAD properties on QKD have been explored extensively, the relationship of spot‐size and spatial position on the full instrumental response and thus quantum bit error rate (QBER) has been studied little. Changes in spot size and spatial position can result from atmospheric turbulence and pointing and tracking errors. Here, An empirical analysis of that relationship is presented utilising a large active area, 500 μm, free‐space coupled Si‐SPAD designed for free‐space QKD. A baseline full‐width at half‐maximum timing jitter of 182 ps and a QBER contribution of 0.1 % for a 1 GHz clock frequency QKD system and 100 ps time‐gating window are reported. The impacts of spot‐size and spatial position can increase the QBER to over 0.3%. The link between the spot‐size and timing jitter will allow the understanding of tolerancing for the alignment of Si‐SPADs within free‐space QKD receiver systems—an important factor in designing properly engineered practical systems and the equipment needed to compensate for atmospheric turbulence and pointing and tracking.
Multi‐layer and timescale optimal power flow control in capacitive coupling inverter‐based microgrids
Authors: Zhang Yongjun , Chen Mingli , Deng Wenyang , Zhong Kanghua , Li Zhongliang
Published: February 2024

Compared with the traditional solution, the microgrid (MG) employed capacitive coupling inverters (CCIs) with higher reactive power capacity can effectively reduce the probability of low voltage. However, because of the special coupling structure, different power flow control methods will greatly affect the cost and operation efficiency of the CCI. A multi‐layer and timescale optimal power flow control considering inverter‐layer is therefore proposed in this paper. Firstly, the power output characteristics of CCI are analyzed, and the power flow control model of CCI with an energy storage unit is established. Secondly, an optimal control method on different timescales was proposed. By coordinating the active power output and the reserved charging state margin of the energy storage unit, the CCI‐MG reactive power regulation with the most economical and minimum loss was realized, so as to achieve long‐term voltage stability and dynamic satisfaction of load demands. Furthermore, the optimal power flow control of CCI is proposed. The simulation results show that the proposed method can effectively realize the optimal control of active and reactive power of MG, and also improve the voltage stability of AC bus under the economical operation of CCI.
A comprehensive high‐level automated driving assistance system with integrated multi‐functionality
Authors: Kong Aijing , Hang Peng , Tang Yu , Wu Xian , Chen Xinbo
Published: February 2024

Advanced Driver Assistance Systems (ADAS) have gained substantial attention in recent years. However, the integration mechanism of multiple functions within ADAS remains unexplored, and the full potential of its functionality remains underutilised. This paper presents a novel multi‐functional integrated High‐level Automated Driving Assistance System that combines the Cruise Control (CC), Adaptive Cruise Control (ACC), Automated Emergency Brake (AEB), and Automated Lane Change (ALC) functions. The presented system utilises a hierarchical framework. The extension multi‐mode switch strategy is established as the superior module and the Event‐Triggered Model Predictive Controller (ETMPC) is designed as the inferior controller. The CC, ACC, and ALC functions are effectively utilised to enhance traffic efficiency, while the AEB function ensures driving safety. To address the time constraints of conventional Model Predictive Control, an event‐trigger mechanism is proposed to reduce computational load. Simulations are conducted using the CarSim and Matlab platforms. The study results demonstrate significant improvements in both safety and traffic efficiency compared to conventional ADAS strategies. Furthermore, the proposed ETMPC method significantly reduces the frequency of solving Optimisation Problems and decreases online computation costs.
New insight into the hard X-ray emission influenced by the type I bursts observed by Insight-HXMT during the outburst of 4U 1636–536
Authors: Peng J. Q. , Zhang S. , Chen Y. P. , Kong L. D. , Wang P. J. , Zhang S. N. , Shui Q. C. , Ji L. , Zhang G. B. , Yan Z. , Tao L. , Qu J. L. , Ge M. Y. , Yu Z. L. , Li J. , Chang Z. , Li Z. S. , Zhang P. , Xiao Y. X. , Zhao S. J.
Published: February 2024

Context.Thermonuclear bursts, also known as type I X-ray bursts, result from unstable nuclear burning of H/He accreted to the surface of neutron stars, lasting from tens to hundreds of seconds. Thermonuclear bursts have an important impact on accretion environments around the neutron stars, such as their disks and coronas, and are therefore a subject of extensive research. Thermonuclear bursts can be used as probes to gain a deeper understanding of the properties of their disks and coronas.

Aims.By analyzing the data from Insight-HXMT and NICER, we can determine the evolution of the significance of the hard shortage in 4U 1636–536 with its spectral state, as well as the evolution of the fraction of deficit with energy. Additionally, we investigate the possible geometry and evolution of the corona in 4U 1636–536 by combining our findings with the results of spectral analysis.

Methods.We extracted the light curves from the Insight-HXMT low-energy, medium-energy, and high-energy data and subtracted their pre-burst emission, which allowed us to estimate the significance of the hard shortages during the bursts. By fitting the spectra, the correlation between the persistent spectral parameters and the significance of the hard shortages could be established. The bursts were then grouped according to the spectral state in which they occurred, and the significance of the hard shortages was estimated. These in turn helped to investigate the evolution of the fraction of deficit with energy.

Results.We find that during the soft state the significance of possible hard X-ray shortage in bursts is almost zero. However, in the hard state, some bursts exhibit significant shortages (> 3σ), while others do not. We attempt to establish a correlation between the significance of the hard X-ray shortage and the spectral parameters, but the data quality and the limited number of bursts prevent us from finding a strong correlation. For bursts with insignificant shortages in the soft state, the fraction of the deficit remains small. However, in the hard state the fraction of deficit for all bursts increases with energy, regardless of the significance of the shortage of individual bursts. For bursts during the hard state, we investigated the evolution of the fraction of deficit during the bursts by stacking the peaks and decays of the bursts, and find that as the flux of the bursts decreases, the energy corresponding to the maximum of the fraction of deficit becomes progressively higher.

Conclusions.We explore the possible geometry and evolution of the corona suggested by the evolution of the fraction of deficit, which is obtained from the spectral and temporal analysis.
The X-ray variability of active galactic nuclei: Power spectrum and variance analysis of the Swift/BAT light curves
Authors: Papadakis I. E. , Binas-Valavanis V.
Published: February 2024

Aims. We study the X-ray power spectrum of active galactic nuclei (AGN) in order to investigate whether Seyfert I and II power spectra are similar or not and whether AGN variability depends on the mass and accretion rate of black holes as well as to compare the power spectra of AGN with the power spectra of Galactic X-ray black hole binaries.

Method. We used 14–195 keV band light curves from the 157-month Swift/BAT hard X-ray survey, and we computed the mean power spectrum and excess variance of AGN in narrow black hole mass and AGN luminosity bins. We fitted a power-law model to the AGN power spectra, and we investigated whether the power spectrum parameters and the excess variance depend on the black hole mass, luminosity, and accretion rate of AGN.

Results. We found the Seyfert I and Seyfert II power spectra to be identical, in agreement with AGN unification models. The mean AGN X-ray power spectrum has the same power-law like shape, with a slope of −1 in all AGN irrespective of their luminosity and black hole mass. We did not detect any flattening to a slope of zero at frequencies as low as 10−9 Hz. We detected an anti-correlation between the power spectral density function (PSD) amplitude and the accretion rate, similar to what has been seen in the past in the 2–10 keV band. This implies that the variability amplitude in AGN decreases with an increasing accretion rate. The universal AGN power spectrum is consistent with the mean 2–9 keV band Cyg X-1 power spectrum in its soft state. We detected a small difference in amplitude, but this is probably due to the difference in energy.

Conclusions. The mean low-frequency AGN X-ray power spectrum is consistent with the extension of the mean 0.01–25 Hz Cyg X-1 power spectrum in its soft state to lower frequencies. We cannot prove that the mean AGN PSD is analogous to the mean Cyg X-1 PSD in its soft state, as we do not know the location of the high-frequency break in the hard X-ray AGN PSDs. However, if this is the case, then the accretion disc in AGN probably extends to the radius of the innermost circular stable orbit (as is probably the case with the black hole binaries in their soft state). The X-ray corona will then be located on top, illuminating the disc and producing the X-ray reflection and disc reverberation phenomena commonly observed in these objects. Furthermore, the agreement between the PSD amplitude in AGN and the Cyg X-1 (either in the soft or the hard state) over many decades in frequency indicates that the X-ray variability process is probably the same in all accreting objects, irrespective of the mass of the compact object. We plan to investigate this issue further in the near future.
Optimisation-based alignment of wide-band integrated superconducting spectrometers for submillimeter astronomy
Authors: Moerman A. , Karatsu K. , Yates S. J. C. , Huiting R. , Steenvoorde F. , Dabironezare S. O. , Takekoshi T. , Baselmans J. J. A. , Brandl B. R. , Endo A.
Published: February 2024

Context. Integrated superconducting spectrometers (ISSs) for wide-band submillimeter (submm) astronomy use quasi-optical systems for coupling radiation from the telescope to the instrument. Misalignment in these systems is detrimental to the system performance. The common method of using an optical laser to align the quasi-optical components requires an accurate alignment of the laser to the submm beam from the instrument, which is not always guaranteed to a sufficient accuracy.

Aims. We develop an alignment strategy for wide-band ISSs that directly uses the submm beam of the wide-band ISS. The strategy should be applicable in both telescope and laboratory environments. Moreover, the strategy should deliver similar quality of the alignment across the spectral range of the wide-band ISS.

Methods. We measured the misalignment in a quasi-optical system operating at submm wavelengths using a novel phase and amplitude measurement scheme that is capable of simultaneously measuring the complex beam patterns of a direct-detecting ISS across a harmonic range of frequencies. The direct detection nature of the microwave kinetic inductance detectors in our device-under-test, DESHIMA 2.0, necessitates the use of this measurement scheme. Using geometrical optics, the measured misalignment, a mechanical hexapod, and an optimisation algorithm, we followed a numerical approach to optimise the positioning of corrective optics with respect to a given cost function. Laboratory measurements of the complex beam patterns were taken across a harmonic range between 205 and 391 GHz and were simulated through a model of the ASTE telescope in order to assess the performance of the optimisation at the ASTE telescope.

Results. Laboratory measurements show that the optimised optical setup corrects for tilts and offsets of the submm beam. Moreover, we find that the simulated telescope aperture efficiency is increased across the frequency range of the ISS after the optimisation.
Funktionelle Stimmtransition von Trans*Frauen – Eine Doppelfallstudie
Authors: Stang Philipp , Gillig Katrina
Published: February 2024

Einleitung Die Stimmtransition ist ein wichtiger Aspekt des Angleichungsprozesses insbesondere für Trans*Frauen.

Methoden Im Rahmen einer explorativen mixed-methods Doppelfallstudie im Längsschnittdesign wurde die logopädische Stimmtransition evaluiert.

Ergebnisse Den als hinreichend weiblich beurteilten Sprechstimmen in den Audioaufnahmen wurde von den Probanden, zwei Trans*Frauen, das Adjektiv „feminin“ zugeschrieben, während von den Logopäden die Adjektive „hoch“ und „hell“ zugeschrieben wurden. Phonetisch beträgt die mittlere Sprechtonhöhe in diesen Aufnahmen 176.02 Hz. bzw. 145.58 Hz. Signifikante Unterschiede mit großen Effektstärken konnten zwischen den Mittelwerten zu WP (Weiblichkeitsbeurteilung der Probandinnen) und ZP (Zufriedenheitsbeurteilung der Probandinnen) der Probandinnen 1 und 2 festgestellt werden. Die Ergebnisse der Audioaufnahmen zeigen einen starken Zusammenhang zwischen Zufriedenheit und Weiblichkeitsbeurteilung bei den Testpersonen und einen mittleren Zusammenhang in der Fremdbeurteilung durch die Logopädinnen. Aus den Interviewergebnissen leiten sich Empfehlungen für einen niederschwelligen Zugang zu relevanten Informations- und Therapieangeboten ab.

Fazit Stimmtraining kann bei Trans*Frauen im Rahmen der Stimmtransition zu einer Steigerung der Stimmhöhe, Weiblichkeitseinschätzung und Zufriedenheit führen.
Synthesis of Stilbenes by Cyanide/Base-Mediated Coupling of Benzylic Chlorides and Alcohols
Authors: Madsen Robert , Schichler Johanna
Published: February 2024

A straightforward procedure has been developed for the direct synthesis of stilbenes from benzylic chlorides and alcohols. The transformation employs a two-step one-pot protocol where the benzylic chloride is first subjected to a substitution with potassium cyanide in o-xylene. Without workup, the resulting arylacetonitrile is then reacted directly with the benzylic alcohol and potassium tert-butoxide to generate the stilbene framework. The condensation has been performed with a variety of commercially available benzylic chlorides and alcohols to afford substituted stilbenes as the pure E-isomers. A kinetic isotope effect of 5.2 has been measured for the overall transformation when comparing benzyl alcohol and α,α-d
2-benzyl alcohol. The release of cyanide during the final elimination to stilbene has been confirmed by a picrate test. Thus, the potassium tert-butoxide-mediated elimination of cyanide is believed to proceed by an E1cB mechanism where the deprotonation reaction constitutes the rate-determining step.
Categorising and cohabiting: practices as the site of biosocial becoming
Authors: Shove Elizabeth , Blue Stanley , Kelly Michael P.
Published: February 2024

In this article we argue that social practices, which consist of sayings and doings that extend across space and time, generate and sustain distinctive patterns of microbial interaction. In taking this approach, we position practice theory within and not outside the realm of contemporary biological processes, including processes that matter for human health. In working towards this conclusion, we show how categories and distinctions (e.g. between communicable and non-communicable disease) are embedded in medical responses and in the lives of potentially harmful bacteria like Helicobacter Pylori. Our next step is to explain how social practices engender patterns of cohabitation, interaction and mutual adaptation between microbes within and beyond the body, processes we illustrate with reference to anti-microbial resistance. The conclusion that human and microbial coexistence is, in various ways, defined by the lives of social practices provides an important bridge between the social and natural sciences and a starting point from which to approach fundamental questions about the dynamics of biosocial becoming, and the part that public policies play in these processes.
The ‘China Threat’: Stereotypical representations in the US competition with China
Authors: Lucenti Flavia
Published: February 2024

When Donald Trump was elected, the idea of the ‘China Threat’ gained popularity. Nonetheless, this was not a novelty. From the early nineties, when the country consolidated its economic growth, concern had begun to spread that China would convert its economic resources into a military force to turn against the US. This article explores whether the concept of the China Threat may have been influenced by stereotypical representations rooted in US academic thinking and shared at the government level. The analysis proceeds by adopting a three-stage approach. First, it draws a theoretical framework that intertwines a constructivist perspective from IR theory with social psychology, referring to Social Representations Theory and theories of stereotypes. Second, while focusing on the expressions ‘Thucydides’ Trap’ and ‘New Cold War’, it describes how the China Threat has been elaborated in the US scholarly agenda. Finally, it discusses how the China Threat has found an outlet especially in the Trump administration’s narrative.
The inferiors imitate the superiors: the government’s low-carbon concerns and the renewable energy technology of firms
Authors: Du Weijian , Li Mengjie , Wang Zhaohua
Published: February 2024

Existing research has focused mainly on the technological effects of rigid constraints such as low-carbon policies, but there has been little exploration of flexible constraints such as the government’s low-carbon concerns. To explore the role of flexible low-carbon constraints and effective paths for achieving low-carbon development, this paper theoretically and empirically investigates the influence of the government’s low-carbon concerns on local firms’ innovation in renewable energy technology and the underlying mechanism. Benchmark analysis shows that the government’s low-carbon concerns can improve renewable energy technology among firms in an area. Mechanism analysis reveals that low-carbon concerns promote firms’ renewable energy technology adoption by increasing the amount of research and development (R&D) investment and government subsidies and energy use costs of firms in the area. Heterogeneity analysis reveals that heterogeneity exists across technologies, firms, industries and locations in terms of the incentive impact of the government’s low-carbon concerns on the level of renewable energy technology innovation. Extensive analysis indicates that the government’s low-carbon concerns have a long-term incentive impact on the renewable energy technology of local firms and a positive demonstration impact on the renewable energy technology of neighboring firms. This study is helpful in that it explores the major driving factors behind the creation of a low-carbon economy and the achievement of climate targets.
Adaptable intelligent filters based on nanotextured nonwoven membranes containing water-insoluble hydrogels
Authors: Wu Jingwei , Pourdeyhimi Behnam , Yarin Alexander L.
Published: February 2024

The work demonstrates, for the first time, thermo-responsive, water-insoluble, hydrogel-based, nano-fibrous filter media comprised of copolymers of N-isopropylacrylamide (NIPAM) and methyl methacrylate formed by electrospinning. Moreover, a comprehensive novel physical explanation of all aspects responsible for the physical mechanisms resulting in the thermo-responsive regulation of the water flow rate and an enhanced interception of nanoparticles by such filter membranes is given. They are the wettable-non-wettable transition, pore, and fiber-size changes, as well as a diminishing filter thickness at the lower critical solution temperature (LCST) of the copolymers developed here, which interplay with a significant reduction in the water viscosity with temperature. Poly(N-isopropylacrylamide) (PNIPAM) hydrogel is an attractive material because of its thermo-responsive properties. Its wettability changes with water temperature. This characteristic holds great promise for the development of advanced filter media and related responsive materials. In this study, PNIPAM hydrogels were designed and transformed into filter membranes for applications in water filtration in biomedical and other related systems. These thermo-responsive filter membranes offer the potential for enhanced filtration efficiency, selectivity, and the overall system performance. Here, two different procedures were adopted to form water-insoluble thermo-responsive filter media based on PNIPAM hydrogels. The PNIPAM-based hydrogels were electrospun, resulting in the formation of thermo-responsive water-insoluble nanofiber membranes. These membranes underwent a series of comprehensive experiments to assess their performance and characteristics, including mass loss, water droplets for the wettability assessment, filtration tests, shrinkage measurements, and microscopic observations. These diverse experiments yield a full understanding of the PNIPAM-based nanofiber membranes’ properties and their potential applications.
Field-tunable Dyakonov surface magnon polaritons in antiferromagnets
Authors: Song Haoyuan , Hao Shaopeng , Liu Qingxin , Fu Shufang , Wang Xuan-Zhang
Published: February 2024

Magnetically ordering media support spin waves or magnons, which can couple with electromagnetic waves to form magnon polaritons. Based on insulating antiferromagnets, magnon polaritons are situated in the far-infrared or THz frequency range. We investigated Dyakonov surface magnon polaritons (DSMPs) at the antiferromagnetic surface in an external magnetic field, where the external field and antiferromagnetic easy axis lie in the surface plane and are normal to each other. Our numerical results are based on the MnF2 crystal, but the conclusions and qualitative results are also available to other insulating antiferromagnets. We predicted two field-tunable DSMPs and one tunable Dyakonov surface magnon. We discerned the main effects of the external magnetic field on the DSMPs; either DSMPs are sensitively modulated by the external field or there is a cutoff magnetic field. Their individual Poynting vector seriously deviates the propagation direction and is sensitively controlled by the external field. The spin angular momentum contains two components normal to each other, unlike conventional surface magnon polaritons. One of the DSMPs can carry a huge Poynting vector and spin angular momentum in the external magnetic field. These results are interesting for micromechanics and spintronics and relevant technologies in the far-infrared or THz domain.
An upgrade of the primary length standard of Republic of Serbia where digital stabilization is performed by Arduino Due board
Authors: Grujić Zoran D. , Nikolić Marko G. , Zelenika Slobodan , Rabasović Mihailo D.
Published: February 2024

An upgrade of the electronic system for frequency stabilization of the HeNe laser, primary length standard of Republic of Serbia, based on digital electronics, is described. Arduino microcontrollers have been used for stabilization, and laptop computer has been used only to communicate with the user. In addition, an analog electronics has been developed in order to boost the performance of the setup. The setup is simple and inexpensive, made of off-the-shelf electronics components. Despite this, good performances have been achieved.
Intense charge transfer plasmons in golden nanoparticle dimers connected by conductive molecular linkers
Authors: Fedorov A. S. , Visotin M. A. , Lukyanenko A. V. , Gerasimov V. S. , Aleksandrovsky A. S.
Published: February 2024

Golden nanoparticle dimers connected by conjugated molecular linkers 1,2-bis(2-pyridyl)ethylene are produced. The formation of stable dimers with 22 nm diameter nanoparticles is confirmed by transmission electron microphotography. The possibility of charge transfer through the linkers between the particles in the dimers is shown by the density functional theory calculations. In addition to localized plasmon resonance of solitary nanoparticles with a wavelength of 530 nm, the optical spectra exhibit a new intense absorption peak in the near-infrared range with a wavelength of ∼780 nm. The emergent absorption peak is attributed to the charge-transfer plasmon (CTP) mode; the spectra simulated within the CTP developed model agree with the experimental ones. This resonant absorption may be of interest to biomedical applications due to its position in the so-called transmission window of biological tissues. The in vitro heating of CTP dimer solution by a laser diode with a wavelength of 792 nm proved the efficiency of CTP dimers for achieving a temperature increase of ΔT = 6 °C, which is sufficient for hyperthermia treatment of malignant tumors. This indicates the possibility of using hyperthermia to treat malignant tumors using the material we synthesized.
Electro-osmotic flow in nanoconfinement: Solid-state and protein nanopores
Authors: Li Minglun , Muthukumar Murugappan
Published: February 2024

Electro-osmotic flow (EOF) is a phenomenon where fluid motion occurs in porous materials or micro/nano-channels when an external electric field is applied. In the particular example of single-molecule electrophoresis using single nanopores, the role of EOF on the translocation velocity of the analyte molecule through the nanopore is not fully understood. The complexity arises from a combination of effects from hydrodynamics in restricted environments, electrostatics emanating from charge decorations and geometry of the pores. We address this fundamental issue using the Poisson–Nernst–Planck and Navier–Stokes (PNP–NS) equations for cylindrical solid-state nanopores and three representative protein nanopores (α-hemolysin, MspA, and CsgG). We present the velocity profiles inside the nanopores as a function of charge decoration and geometry of the pore and applied electric field. We report several unexpected results: (a) The apparent charges of the protein nanopores are different from their net charge and the surface charge of the whole protein geometry, and the net charge of inner surface is consistent with the apparent charge. (b) The fluid velocity depends non-monotonically on voltage. The three protein nanopores exhibit unique EOF and velocity–voltage relations, which cannot be simply deduced from their net charge. Furthermore, effective point mutations can significantly change both the direction and the magnitude of EOF. The present computational analysis offers an opportunity to further understand the origins of the speed of transport of charged macromolecules in restricted space and to design desirable nanopores for tuning the speed of macromolecules through nanopores.
Hydrodynamic collision and deformation of compound droplet pairs in confined shear flow
Authors: Al Mamun S. M. Abdullah , Farokhirad Samaneh
Published: February 2024

In this study, we numerically investigate the collision dynamics of core–shell compound droplet pairs under confined shear flow conditions. We focus on three collision modes: pass-over, coalescence, and reverse-back motions, analyzing their motion trajectories and morphological evolution. Notably, the coalescence mode exhibits significant dynamic behavior during evolution. However, the coalescence behavior of compound droplet pairs, as well as the impact of geometric parameters, including the initial vertical offset of droplets and the degree of confinement, on their dynamic behaviors, remains largely unexplored and unquantified. Our simulation results reveal that core droplets have little effect on the trajectory of droplet pairs during their pass-over and reverse-back motions, yet they significantly affect the dynamics in the coalescence mode. Additionally, we have addressed how the interplay between the core-shell size ratio, initial offset, and wall confinement affects the transition between collision modes, morphology, trajectory, and final state of the droplet pairs. Our findings show that an increase in the core–shell size ratios restricts the deformability of the shell droplets. Furthermore, in the coalescence mode, larger core droplets coalesce more rapidly due to spatial adjustment, expediting the stabilization of the newly formed compound droplet. While the size of the core droplets does not alter the transition boundary from coalescence to reverse-back mode based on initial vertical offset, they significantly influence the transition from coalescence to pass-over mode. Moreover, by analyzing confinement as another crucial geometric factor, we demonstrate the coupling effects of confinement and initial vertical offset on the transition between different collision modes.
A model for micro-front dynamics using a
ϕ
4 equation
Authors: Figueroa Elram S. , Trejo-Soto Claudia , García-Ñustes Mónica
Published: February 2024

In this article, we propose a numerical model based on the ϕ4 equation to simulate the dynamics of a front inside a microchannel that features an imperfection at a sidewall to different flow rates. The micro-front displays pinning–depinning phenomena without damped oscillations in the aftermath. To model this behavior, we propose a ϕ4 model with a localized external force and a damping coefficient. Numerical simulations with a constant damping coefficient show that the front displays pinning–depinning phenomena showing damped oscillations once the imperfection is overcome. Replacing the constant damping coefficient with a parabolic spatial function, we reproduce accurately the experimental front–defect interaction.
A novel bearing current signal diagnosis method combining variational modal decomposition and improved random forests
Authors: Zhang Heyu , Zheng Yuqiao , Lu Jieshan
Published: February 2024

A new fault diagnosis approach based on bearing current signals is proposed in this paper. First, in view of strong background noise of the current signal, the variational modal decomposition method is applied to decompose the bearing current signal to obtain multiple intrinsic mode functions, and then the intrinsic mode functions are constructed as the input feature vector according to the kurtosis. Second, to avoid the influence of random forest parameters on the random forest classifier, a random forest faulty bearing diagnostic model optimized by the whale algorithm is established. Finally, the accuracy rate and confusion matrix are adopted to evaluate the prediction effects of both established and traditional models. The classification accuracy of the real damaged bearing fault type can reach 95.11%. The fault diagnosis accuracy of manually damaged bearings can reach 93.83%. The results show that the method proposed in this paper has high accuracy and good generalization ability for bearing fault diagnosis.