bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spin-charge separation and quantum spin Hall effect of $$\beta$$-bismuthene
Authors: Tyner Alexander C. , Goswami Pallab 
Published: July 2023

AbstractMultiple works suggest the possibility of classification of quantum spin Hall effect with magnetic flux tubes, which cause separation of spin and charge degrees of freedom and pumping of spin or Kramers-pair. However, the proof of principle demonstration of spin-charge separation is yet to be accomplished for realistic, ab initio band structures of spin-orbit-coupled materials, lacking spin-conservation law. In this work, we perform thought experiments with magnetic flux tubes on $$\beta$$
β
-bismuthene, and demonstrate spin-charge separation, and quantized pumping of spin for three insulating states, that can be accessed by tuning filling fractions. With a combined analysis of momentum-space topology and real-space response, we identify important role of bands supporting even integer invariants, which cannot be addressed with symmetry-based indicators. Our work sets a new standard for the computational diagnosis of two-dimensional, quantum spin-Hall materials by going beyond the $$\mathbb {Z}_{2}$$

Z
2

paradigm and providing an avenue for precise determination of the bulk invariant through computation of quantized, real-space response.
A study on the influencing factors and related paths of farmer’s participation in food safety governance—based on DEMATEL-ISM-MICMAC model
Authors: Xie Jie-Hui , Tian Fu-Jun , Li Xue-Yuan , Chen Yu-Qing , Li Shi-Yi 
Published: July 2023

AbstractFarmers' participation in food safety governance is an important part of food safety social co-governance, and the accurate identification of its influencing factors and their related paths is of guiding significance to the scientific decision-making of food safety governance. The system of influencing factors of farmers' participation in food safety governance was constructed from four dimensions, and the influence network of each dimension was revealed by decision laboratory analysis (DEMATEL). The hierarchical structure and correlation path of influencing factors were determined by interpretive structural model (ISM), and the attributes of influencing factors were further classified by cross influence matrix multiplication (MICMAC). The results show that the influencing factors of farmers' participation in food safety governance can be divided into seven levels, among which the level of education and the status of village cadres are the fundamental characteristic factors. The degree of rural informatization, the intensity of government supervision, the promotion of village committees, the response of the government and the degree of disclosure of government information are the deep core factors, and risk cognition, political trust and family eating habits are special factors. Taking the importance and attribute status of farmers' participation in food safety governance into decision-making considerations is of great significance to improve the efficiency of food safety governance.
Molecular detection of human Plasmodium species using a multiplex real time PCR
Authors: Lazrek Yassamine , Florimond Célia , Volney Béatrice , Discours Manon , Mosnier Emilie , Houzé Sandrine , Pelleau Stéphane , Musset Lise 
Published: July 2023

AbstractMolecular detection methods have revealed higher sensitivity and specificity than conventional microscopy or rapid diagnostic tests for malaria diagnosis. In this study, we implemented, evaluated and validated according to the ISO 15,189 requirements, a multiplex real-time PCR assay to detect and identify the five human malaria parasites. DNA samples were extracted from whole blood or dried blood spots drawn from patients. Based on the External Quality Assessment (whole blood), this method shows 100% sensitivity and specificity. This PCR detected P. vivax up to 0.25 p/µl, P. falciparum and P. knowlesi up to 0.5 p/µl, P. ovale up to 1 p/µl and P. malariae up to 5 p/µl of blood. From blood spots (extraction from four punches), it detected P. vivax at 5 p/µl, P. falciparum, P. ovale and P. knowlesi at 20 p/µl and P. malariae at 125 p/µl. In conclusion, this quantitative PCR shows excellent performance, is easy to use and DNA saver. It is especially useful to actively screen large population groups and identify the five human malaria parasites in a context of low malaria transmission.
A 1500-year record of mercury isotopes in seal feces documents sea ice changes in the Antarctic
Authors: Liu Hongwei , Zheng Wang , Bergquist Bridget A. , Gao Yuesong , Yue Fange , Yang Lianjiao , Sun Liguang , Xie Zhouqing 
Published: July 2023

AbstractTemporal and spatial variations in sea ice coverage at high Northern Hemisphere latitudes have been shown to affect the photodegradation of methylmercury in seawater and the mercury isotope signatures in biological samples, suggesting the potential of mercury isotopes to reconstruct sea ice variability. Here we study the mercury isotopic composition of a 1500-year sediment profile strongly affected by seal activities on the Fildes Peninsula, King George Island, Antarctic Peninsula. The mass independent isotope fractionation of mercury (represented by Δ199Hg) in sediments dominated by seal feces input reflects the Δ199Hg of marine methylmercury before entering the food web, documenting the changes in the degree of photodemethylation. We found much higher Δ199Hg in sediments deposited during a warm period (~700-1000 years ago), suggesting that reduced sea ice promoted greater photodemethylation. Thus, this study demonstrates the modulation of methylmercury photodegradation by sea ice in the Antarctic, and that mercury isotopes can record historical sea ice changes.
Observation of positive trions in α-MoO3/MoS2 van der Waals heterostructures
Authors: Kumar Ravindra , Mishra Vikash , Dixit Tejendra , Barman Prahalad Kanti , Nayak Pramoda K. , Rao M. S. Ramachandra 
Published: July 2023

vdW heterostructure of α-MoO3/MoS2 leads to formation of a quasiparticle (+ve trion) due to charge transfer from MoS2 to α-MoO3.
Analysis of Noun Phrase Ambiguity in Narratives Reveals Differences in Referential Establishment But Not Cohesion for Older Autistic Children
Authors: Zane Emily , Grossman Ruth B. 
Published: July 2023

Purpose:
Stories told by autistic narrators often contain relatively frequent use of ambiguous references. However, it remains unclear whether this ambiguity is driven by ambiguous character establishment (e.g., “Once upon a time, she/the girl…”) and/or ambiguous cohesion (e.g., “Two girls lived in a castle. She/The girl…”). In this study, we directly compared rates of each type of ambiguity within and between narratives told by autistic and non-autistic children, to determine which type of ambiguity is relatively more common in narratives told by autistic children.

Method:

Thirty-three 10- to 17-year-old autistic participants (
n
= 17) and non-autistic peers (
n
= 16), who were not statistically different in age, standardized language scores, and IQ scores (
p
> .8 for all), watched two short animated videos alone and then described the videos' events to two listeners who were openly unfamiliar with the videos. We transcribed video recordings of narratives and coded all referential noun phrases (NPs) as either clear or ambiguous. We further categorized ambiguous NPs as either ineffective introduction or ineffective cohesion.

Results:
Autistic children produced significantly higher rates of ambiguous establishment than non-autistic peers, whereas between-group comparisons' rates of ambiguous cohesion were not statistically significant.

Conclusions:
Older children on the autism spectrum show differences in the way they introduce characters, selecting NP types that are only appropriate when their listener is already familiar with the referent. In contrast, once they have introduced characters, they show cohesive skills that are comparable to those of non-autistic peers. Findings support theories arguing that autistic children show differences in their application of social pragmatic principles (listener/context-specific pragmatic rules), whereas their use of linguistic pragmatics (context-independent rules) is similar to that of non-autistic peers.
Adaptive NN control for nominal backstepping form with periodically time‐varying and nonlinearly parameterized switching functions
Authors: Yang Xiaoli , Li Jing , Ge Shuzhi Sam , Li Xiaobo 
Published: July 2023

AbstractIn this paper, the prescribed tracking performance control problem is addressed for uncertain nonlinear systems with unknown periodically time‐varying parameters and arbitrary switching signal. By utilizing radial basis function neural network and fourier series expansion, an approximator is developed to overcome the difficulty of identifying unknown periodically time‐varying and nonlinearly parameterized functions. To achieve the ideal tracking control performance and eliminate the influence of filtering error, a novel command filter‐based adaptive neural network prescribed tracking performance controller is designed by introducing a filtering compensation mechanism. Differently from the standard Backstepping technique, the proposed control scheme eliminates the “explosion of complexity” problem and relaxes the constraint condition on the reference signal. And then, it is warranted that the closed‐loop system is semi‐globally ultimately uniformly bounded and the tracking error is always limited to the specified region bounded by the performance functions. Three simulation examples are used to demonstrate the feasibility of the developed technique in this paper.
Impact of air pressure variations on electrical vehicle motor insulation
Authors: Wang Peng , Yu Chaofan , Akram Shakeel , Fan Ziyuan , Zhao Wenhuan 
Published: July 2023

AbstractVariation in air pressure severely affects the insulation of electric vehicle (EV) motors, hence weakening the reliability of EVs for safe operation. Nomex‐polyimide‐Nomex, a typical insulation material for EV motors, was used to investigate the motor insulation performance under different air pressures. The results show that the partial discharge inception voltage is significantly reduced for EV motors operated at lower air pressures, and the probability of partial discharge (PD) occurrence is increased. The macroscopic results reveal that the active area of the PD expands at low pressure, while the non‐corroded ring appears in the centre. Additionally, although the number and amplitude of the PD increase significantly with decrease in air pressure, the active area of the PD expands and electrical stress on the insulation per unit area increases slowly. Therefore, when the pressure decreased from 60 to 40 kPa, the endurance life does not show a significant downward trend. Furthermore, the dielectric constant and loss of the low‐pressure samples significantly change during the ageing process, which further indicates critical degradation of the insulation. The aforementioned investigations reveal that the air pressure at different altitudes has a significant impact on the performance of insulation materials.
Effects of gender and degree of formality on the use of euphemistic strategies in Iraqi Arabic
Authors: Mohammed Dawood Milad , Alghazo Sharif , Jarrah Marwan 
Published: July 2023

AbstractAlthough euphemism has been studied in many Arabic dialects, it has not yet received due attention in Iraqi Arabic (IA). This study investigates the use of euphemistic strategies by IA speakers and the effect of gender and degree of formality on the use of these strategies. In order to achieve these objectives, a discourse completion test (DCT) was developed and distributed to 160 (80 males and 80 females) Iraqi university students. The data were analysed quantitively and qualitatively using strategies adopted from a number of previous frameworks. The findings show that the participants used a variety of euphemistic strategies, with the deletion strategy being the most frequently used when talking about the topic of death, the fuzzy words strategy for the topic of mental illness, and the implication strategy for the topic of obesity. The analysis also revealed that the degree of formality plays a key role in the use of euphemistic strategies in the topic of mental illness and that gender plays an effective role in the use of euphemistic strategies in all three topics.
The simulation study of broadband quasi-phase-matching second harmonic generation based on orientation-patterned gallium phosphide and gallium antimonide
Authors: Hu Ruilin , He Qiang 
Published: July 2023

Orientation-patterned gallium phosphide (OP-GaP) and orientation-patterned gallium antimonide (OP-GaSb) have demonstrated excellent potential for broadband second harmonic generation (SHG), with a wide range of fundamental wavelengths and temperature tunability, making them promising candidates for use in various applications. In this paper, an analytical demonstration of forward and backward broadband SHG is presented, delivering the fundamental wavelengths in 0.7–12.5 and 2.4–9.8 µm, respectively, through the utilization of OP-GaP and OP-GaSb with quasi-phase-matching (QPM). The temperature tuning ranges for OP-GaP and OP-GaSb are −195–176 and −192–126 °C, respectively. OP-GaP and OP-GaSb can obtain forward broadband QPM SHG when the conditions of QPM and group-velocity matching (GVM) are satisfied simultaneously. The bandwidths of OP-GaP and OP-GaSb with lengths of 10 mm are found to be 776 and 484 nm, respectively, in the forward GVM fundamental wavelength for forward broadband SHG at 25 °C. The bandwidths for backward broadband SHG in the forward GVM fundamental wavelength are also calculated, but the results showed that OP-GaP and OP-GaSb can only achieve forward broadband QPM SHG. Variations of the GVM fundamental wavelength have also been demonstrated as a function of temperature.
Tellurium nanosheets with structural anisotropy formed from defective MoTe2 multilayers
Authors: Muranaka Shuto , Nogamida Satoshi , Hara Kosuke O. , Sawano Kentarou , Hoshi Yusuke 
Published: July 2023

We report on the formation of a tellurium nanosheet with a MoOx cap by thermal annealing of ion-implanted 2H–MoTe2 multilayers. The presence of crystal defects generated by ion implantation at an energy of 90 keV accelerates the incorporation of O atoms and the surface desorption of Te atoms in the defective MoTe2 during thermal annealing, and subsequently, a tellurium nanosheet is formed around the bottom regions in the defective MoTe2 due to tellurium segregation. For the angle-resolved Raman spectroscopy, polar plots exhibit two-fold and four-fold symmetries for peak intensities of 121 and 143 cm−1, respectively, signifying the structural anisotropy of the tellurium nanosheet. On reducing the ion energy, the two Raman peak intensities collected from the tellurium nanosheet remarkably decrease, and they disappear for the sample at 30 keV. On the other hand, the decrease of the implantation energy increases the E2g peak intensity at 235 cm−1, which corresponds to the in-plane vibration mode of 2H–MoTe2. The distribution of crystal defects along the depth direction tuned by ion implantation energy is very critical for the formation of a tellurium nanosheet with structural anisotropy from the 2H–MoTe2 multilayers.
Estimating the properties of single positive air streamers from measurable parameters
Authors: Bouwman Dennis , Francisco Hani , Ebert Ute 
Published: July 2023

Abstract
We develop an axial model for single steadily propagating positive streamers in air. It uses observable parameters to estimate quantities that are difficult to measure. More specifically, for given velocity, radius, length and applied background field, our model approximates the ionization density, the maximal electric field, the channel electric field, and the width of the charge layer. These parameters determine the primary excitations of molecules and the internal currents. Our approach is to first analytically approximate electron dynamics and electric fields in different regions of a uniformly-translating streamer head, then we match the solutions on the boundaries of the different regions to model the streamer as a whole, and we use conservation laws to determine unknown quantities. We find good agreement with numerical simulations for a range of streamer lengths and background electric fields, even if they do not propagate in a steady manner. Therefore quantities that are difficult to access experimentally can be estimated from more easily measurable quantities and our approximations. The theoretical approximations also form a stepping stone towards efficient axial multi-streamer models.
Solving local constraint condition problem in slave particle theory with the BRST quantization
Authors: Luo Xi , Liu Jianqiao , Yu Yue 
Published: July 2023

Abstract
With the Becchi–Rouet–Stora–Tyutin (BRST) quantization of gauge theory, we solve the long-standing difficult problem of the local constraint conditions, i.e. the single occupation of a slave particle per site, in the slave particle theory. This difficulty is actually caused by inconsistently dealing with the local Lagrange multiplier λ

i
which ensures the constraint: in the Hamiltonian formalism of the theory, λ

i
is time-independent and commutes with the Hamiltonian while in the Lagrangian formalism, λ

i
(t) becomes time-dependent and plays a role of gauge field. This implies that the redundant degrees of freedom of λ

i
(t) are introduced and must be removed by the additional constraint, the gauge fixing condition (GFC) ∂
t

λ

i
(t) = 0. In literature, this GFC was missed. We add this GFC and use the BRST quantization of gauge theory for Dirac’s first-class constraints in the slave particle theory. This GFC endows λ

i
(t) with dynamics and leads to important physical results. As an example, we study the Hubbard model at half-filling and find that the spinon is gapped in the weak U and the system is indeed a conventional metal, which resolves the paradox that the weak coupling state is a superconductor in the previous slave boson mean field (MF) theory. For the t–J model, we find that the dynamic effect of λ

i
(t) substantially suppresses the d-wave pairing gap and then the superconducting critical temperature may be lowered at least a factor of one-fifth of the MF value which is of the order of 1000 K. The renormalized T

c
is then close to that in cuprates.
Comparative Study on the Compression Sintering Performance of Different Kinds of Copper-Chromium Powder Applied to Electrical Contact Materials
Authors: Pan Xu , Zhang Jingguo , Ke Xin , Xie Bingqing , Wang Jianwei , Wang Zhong , Wang Limin , Li Zhanrong 
Published: July 2023

Abstract
In this paper, the pressing and sintering properties of three kinds of copper-coated chromium composite powder and copper-chromium mechanical mixed powder with the same copper content were compared and studied. The copper-coated chromium composite powder was prepared by a diffusion sintering method, a liquid electroless plating method, and a diffusion sintering method with an added binder. The results show that with the increase in copper content, the pressing advantage of copper-clad chromium powder is more obvious. The density, hardness, and size shrinkage of the sintered sample are more stable. Moreover, the uniform distribution of Cu and Cr in the copper-coated chromium powder sintered sample can effectively improve the composition uniformity of Cu Cr electrical contact alloy.
Study on Performance Evaluation of Multifunctional Microgel System
Authors: Ye Yinzhu , Liu Yang , Guan Baoshan , Tian Yongda , Shao Liming , Yu Zhentao , Zeng Zhihui , Li Shichao 
Published: July 2023

Abstract
Soft Microgel (SMG) used to enhance oilfield recovery is a kind of aqueous dispersion chemical agent system of microgel particles. It is usually used in medium and low permeability reservoirs and is generally not used for plugging large pores of reservoirs due to the limitation of particle size. To resolve the problem that SMG cannot effectively block large pores of the reservoir, the multi-functional system (SMG-w) can be synthesized by introducing inorganic components into SMG under special conditions. The main physical and chemical properties of SMG-w are carried out in the laboratory. The results of the study show that SMG-w has an excellent resistant ability to temperature and salinity. Besides, it can also decrease the interfacial tension of oil and water. What’s more, it can react with Ca2+ or Mg2+ in formation water from a large number of flocs in the high salinity reservoir, which can enhance physical and chemical properties of SMG-w and make it be applied in deep profile control of high permeability reservoirs with high temperature and high salinity.
A review of thermoresponsive drug delivery systems based on LCST/UCST polymer nanofibers
Authors: Shu Xin 
Published: July 2023

Abstract
Drug delivery systems and thermoresponsive polymers are garnering more interest due to technological advancement. The synthesis, characteristics, and uses of stimuli-responsive polymers in drug delivery systems are discussed in this paper. LCST and UCST polymers, two subtypes of thermoresponsive polymers, are also discussed, along with their processes and biomedical applications. The paper also discusses the use of conventional nanofibers and stimuli-responsive nanofibers for drug delivery systems and the most recent developments in electrospinning technology. The article also analyses the difficulties facing drug delivery systems today. This paper makes the case that novel electrospinning technologies must be developed in addition to further research into drug delivery systems based on UCST polymers with strong biocompatibility and biodegradability.
Study on Efficient Determination of the Content of Key Elements in Thin Stainless Steel by Spark Discharge Optical Emission Spectrometry with Contrivable Sample Thickening
Authors: Yuan Meng , Zhong Fengping , Huang Liuyi , Jin Shuo , Peng Chao , Volodymyr Korzhyk 
Published: July 2023

Abstract
Spark discharge optical emission spectrometry is one of the most effective methods to accurately determine the chemical composition of stainless steel and other metal materials. However, when the thickness of the sample to be tested is less than 3 mm, the test stability of this method decreases and the sample is at risk of breakdown. In this paper, we studied the surface morphology of the excited samples by optical microscope and scanning electron microscope, and analyzed the reasons that affected the testing instability of thin samples. An auxiliary thickening device was proposed to improve the excitation stability of this method, and we realized the efficient determination of key chemical components in thin stainless steel samples. Accurate and stable test results were obtained for 304 stainless steel thin samples with different thicknesses of 1 to 3 mm.
Study on preparation and application of NaCl-KCl-CsCl-Cs2ZrCl6 composite electrolyte
Authors: Zou Wenzhen , Wu Yanke , Wang Lijun 
Published: July 2023

Abstract
Preparing zirconium chloride composite salts such as Cs2ZrCl6 can replace highly volatile ZrCl4 for studying molten salt electrolytic refining zirconium. The NaCl-KCl-CsCl-Cs2ZrCl6 composite electrolyte was prepared using ternary molten salt with a molar ratio of NaCl: KCl: CsCl=30: 24.5: 45.5 and ZrCl4 as raw materials. According to thermodynamic analysis, ZrCl4 preferentially reacts with CsCl to form Cs2ZrCl6 with strong stability. X-ray diffraction analysis showed that the main phase of the product was Cs2ZrCl6. ICP-DSC analysis showed that the conversion rate of ZrCl4 to Cs2ZrCl6 reached 99.68%. To verify the properties of this electrolyte, it is applied to molten salt electrolytic refining sponge zirconium. Studies have shown that this electrolyte system obtains dendrite zirconium products with a maximum grain size of 6.29mm, a system with more application prospects.