bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pesticide extraction from soil into runoff under a rainfall simulator
Authors: Silburn D. Mark 
Published: February 2023

Context Runoff estimation is an important aspect of pesticide environmental behaviour and is the major loss pathway to the environment. Aims To improve understanding of pesticide runoff. Methods Data from three rainfall simulator studies was used. Twelve pesticides were studied ranged from tightly sorbed (DDE, soil sorption coefficient (KD) ~15 000 L kg−1) to weakly sorbed (dimethoate, KD < 30). Key results Event runoff pesticide concentrations were closely related to soil concentrations (0–25 mm depth). The ratio of runoff to soil concentration (the runoff extraction ratio, ERO), was similar for pesticides with a wide range of sorption and across the three soils: runoff concentration (μg L−1) = 28 × soil concentration (mg kg−1). ERO decreased with time after spraying, presumably due to lower concentrations in the top few mm of soil. Conclusions This model provides improved or similar estimates of pesticide runoff than previous models. Similar ERO values between sites was probably due to similar hydrology (high rainfall intensity, surface sealing, moist subsoils) and erosion, and because the same masses of soil and water are involved in mixing. Reduction in runoff concentrations by leaching was not influential, because infiltration was small and soil sorption too high. Implications Conditions studied apply during summer storms on most cotton and grain land on clay soils in the northern grain and cotton lands in eastern Australia. The model should be applicable under these conditions.
Deflection in higher dimensional spacetime and asymptotically non-flat spacetimes
Authors: He Jinhong , Wang Qianchuan , Hu Qiyue , Feng Li , Jia Junji 
Published: February 2023

Abstract
Using a perturbative technique, in this work we study the deflection of null and timelike signals in the extended Einstein–Maxwell spacetime, the Born–Infeld gravity and the charged Ellis–Bronnikov (CEB) spacetime in the weak field limit. The deflection angles are found to take a (quasi-)series form of the impact parameter, and automatically takes into account the finite distance effect of the source and observer. The method is also applied to find the deflections in CEB spacetime with arbitrary dimension. It’s shown that to the leading non-trivial order, the deflection in some n-dimensional spacetimes is of the order

. We then extended the method to spacetimes that are asymptotically non-flat and studied the deflection in a nonlinear electrodynamical scalar theory. The deflection angle in such asymptotically non-flat spacetimes at the trivial order is found to be not π anymore. In all these cases, the perturbative deflection angles are shown to agree with numerical results extremely well. The effects of some nontrivial spacetime parameters as well as the signal velocity on the deflection angles are analyzed.
Oxygen vacancy related hole fast trapping in high mobility cubic-Ge/ZrO2 interface
Authors: Liu Zhu-You , Cai Xuefen , Zhang Cai-Xin , Cao Ru-Yue , Liu Yue-Yang , Deng Hui-Xiong 
Published: February 2023

Abstract
Ge has the potential to replace Si as the future field-effect transistors channel material due to its superior hole mobility, and cubic zirconia with high dielectric constant and small lattice mismatch can be selected as its oxide layer. At present, the mechanism of charge trapping caused by defects in the Ge oxide layer interface and bulk of such device has not been accurately analyzed. In our work, we have constructed the cubic Ge/ZrO2 interface, and studied the electronic structure and hole trapping characteristics of the interface structure by first-principles hybrid-functional calculations with Marcus theory. According to research oxygen vacancies with the different distances (abbr. d
O-int) away from the Ge substrate, we confirm that the oxygen vacancy can act as a fast trap center to capture the hole of the valence band maximum (VBM) from Ge, resulting in the ultrafast or fast transient charge trapping in the high-k gate dielectric. We found that, when a given range of applied electric field, the hole trap is ultrafast with capture time of 10−6–10−5

μ

s

when d
O-int is within the range of 2–7

A

∘

, and there is a 2–3 order of magnitude increases in capture time as d
O-int exceeds 7

A

∘

with the maximum capture cross section reducing substantially. Here, our work provides a clear and reasonable description of the distance-dependent hole trapping process at the Ge/high-k dielectrics metal-oxide-semiconductor (MOS) devices and provides significant support for solving the reliability problem of microelectronic devices.
Compact thin-film lithium niobate modulators using slotted coplanar waveguide electrode suitable for high-volume fabrication
Authors: Li Heng , Tang Yongqian , Chen Quanan , Dai Xiangyang , Li Xiaohan , Lu Mingzhi , Lu Qiaoyin , Guo Weihua 
Published: February 2023

Abstract
Lithium niobate (LN) is a good candidate for fabricating modulators due to its superior material characteristics. However, the application of traditional LN modulators is limited due to their large footprint and low modulation efficiency resulting from weak optical confinement. In recent years, with the development of the thin-film lithium niobate (TFLN) platform and LN etching technology, the size of the optical mode of the TFLN modulator is 20 times smaller than that of the traditional LN modulator. Furthermore, TFLN modulators have demonstrated a wide bandwidth, low half-wave voltage and small footprint in recent reports. The length of the TFLN modulators can be further reduced by employing a folded design and therefore applicable to compact transceiver package, such as being packaged in the quad small form factor pluggable double density transceiver. In this paper, we report on a folded TFLN modulator fabricated from a 4 inch LN wafer, which is suitable for large-volume fabrication. A fiber-to-fiber insertion loss of 2.5 dB and a voltage–length product of 1.85 V cm have been achieved. The measured electro-optic response curve has a 2.3 dB roll-off at 40 GHz, and the simulated 3 dB bandwidth reaches 65 GHz. Compared to traditional coplanar waveguide traveling wave electrodes, the slotted coplanar waveguide traveling wave electrode (slotted CPW-TWE) design adopted in this work allows adjusting the high-speed characteristics and modulation efficiency with more flexibility. This is the first time a slotted CPW-TWE design has been applied in a folded TFLN modulator.
Les Houches 2021—physics at TeV colliders: report on the standard model precision wishlist
Authors: Huss Alexander , Huston Joey , Jones Stephen , Pellen Mathieu 
Published: February 2023

Abstract
Les Houches activities in 2021 were truncated due to the lack of an in-person component. However, given the rapid progress in the field and the restart of the LHC, we wanted to continue the bi-yearly tradition of updating the standard model precision wishlist. In this work we therefore review recent progress (since Les Houches 2019) in fixed-order computations for LHC applications. In addition, necessary ingredients for such calculations such as parton distribution functions, amplitudes, and subtraction methods are discussed. Finally, we indicate processes and missing higher-order corrections that are required to reach the theoretical accuracy that matches the anticipated experimental precision.
The structure and multifunctionality of high-boron transition metal borides
*
Authors: Zhao Bo , Wang Lu , Tao Qiang , Zhu Pinwen 
Published: February 2023

Abstract
High boron content transition metal (TM) borides (HB-TMBs) have recently been regarded as the promising candidate for superhard multifunctional materials. High hardness stems from the covalent bond skeleton formed by high content of boron (B) atoms to resist deformation. High valence electron density of TM and special electronic structure from p-d hybridization of B and TM are the sources of multifunction. However, the reason of hardness variation in different HB-TMBs is still a puzzle because hardness is a complex property mainly associated with structures, chemical bonds, and mechanical anisotropy. Rich types of hybridization in B atoms (sp, sp2, sp3
) generate abundant structures in HB-TMBs. Studying the intrinsic interaction of structures and hardness or multifunction is significant to search new functional superhard materials. In this review, the stable structure, hardness, and multifunctionality of HB-TMBs are summarized. It is concluded that the structures of HB-TMBs are mainly composed by sandwiched stacking of B and TM layers. The hardness of HB-TMBs shows a increasing tendency with the decreasing atom radius. The polyhedron in strong B skeleton provides hardness support for HB-TMBs, among which C2/m is the most possible structure to meet the superhard standard. The shear modulus (G
0) generates a positive effect for hardness of HB-TMBs, but the effect from bulk modulus (G
0) is complex. Importantly, materials with a value of B
0/G
0 less than 1.1 are more possible to achieve the superhard standard. As for the electronic properties, almost all TMB3 and TMB4 structures exhibit metallic properties, and their density of states near the Fermi level are derived from the d electrons of TM. The excellent electrical property of HB-TMBs with higher B ratio such as ZrB12 comes from the channels between B–B π-bond and TM-d orbitals. Some HB-TMBs also indicate superconductivity from special structures, most of them have stronger hybridization of d electrons from TM atoms than p electrons from B atoms near the Fermi level. This work is meaningful to further understand and uncover new functional superhard materials in HB-TMBs.
Decay processes of long-lived phonons in 6H-SiC
Authors: Pshenay-Severin D A , Adamov R B , Vinnichenko M Ya , Moldavskaya M D , Shalygin V A 
Published: February 2023

Abstract
Temperature evolution of the high-resolution far-infrared transmission spectra of 6H-SiC single crystal slab is experimentally examined in a temperature range of 5–320 K. Temperature dependences of the phonon lifetimes for long-lived phonons, namely the IR active folded transverse acoustic (FTA) phonon doublet, are determined. These dependences are interpreted in the framework of a theoretical model developed using first principle anharmonic lattice dynamics. It is shown that three-phonon anharmonic processes dominate in the FTA phonon decay at temperatures above 160 K resulting in a rapid decrease of the phonon lifetimes with increasing temperature. Contribution of four-phonon anharmonic processes is negligibly small at temperatures below 320 K.
Demodulated synchrosqueezing S-transform and its application to machine-fault diagnosis
Authors: Liu Wei , Liu Yang , Li Shuangxi , Zhai Zhixing 
Published: February 2023

Abstract
The time–frequency analysis (TFA) technique has been viewed as a useful tool for processing non-stationary signals in the field of industrial machinery. Rub-impacts of a rotor system will cause vibration of the rotor and stator, thus any vibration signal with rub-impacts will be accompanied by high-frequency oscillation characteristics. In this paper, a novel TFA algorithm, termed a demodulated synchrosqueezing S-transform (DSSST), is proposed to extract the strong time-varying features in rub-impact vibration signals. The DSSST method is based on a modified S-transform, and introduces a pre-processing technique, a demodulation algorithm, to partially demodulate the oscillated modes for rub-impact identification. Meanwhile, a synchrosqueezing transform is utilized to further sharpen the time–frequency representation. Assisted by the proposed method, the rub-impact phenomenon and its impact frequency are clearly recognized through experimental and real validations.
Comparing the images formed by uses of lens surfaces
Authors: Isik Hakan 
Published: February 2023

Abstract
In this study, university students’ experiences with conventional and novel applications for the surfaces of biconvex and biconcave lenses were examined. This work used practical tools to depict refraction and reflection processes that occur on lens surfaces. In the main activity, the surfaces of each lens were used by the students to examine a single image created by refracted light rays and then two images created by reflected light rays. When the students compared the properties of virtual and real images, they discovered that viewing both real and virtual images at the same time is more beneficial and simulating than viewing each image type separately.
Enhancement of nonvolatile memory characteristics caused by GaN/AlN resonant tunneling diodes
Authors: Nagase Masanori , Takahashi Tokio , Shimizu Mitsuaki 
Published: February 2023

Abstract
This paper reports an enhancement of the nonvolatile memory characteristics of GaN/AlN resonant tunneling diodes (RTDs) by reducing the crystal defects in the quantum well structure. Pit-shaped crystal defects are strongly suppressed when pure N2, instead of a N2/H2 mixture, is used as a carrier gas and trimethylindium is introduced as a surfactant for metalorganic vapor phase epitaxy of the quantum well structure. In addition, the density of dislocations is lowered by controlling the growth conditions and structure of the buffer layer between a GaN/AlN RTD and a sapphire (0001) substrate. The leakage current through the quantum well structure is lowered, and an extremely high ON/OFF of >1300, which is 20 times higher than the values obtained in previous studies, is induced. Theoretical calculations based on Poisson’s equation and the Tsu–Esaki formula indicate that a high ON/OFF ratio of >103 can be enhanced by increasing the density of electrons accumulating in the quantum well to a level on the order of 1018 cm–3. Furthermore, nonvolatile memory operations were performed by inputting the sequential pulse voltages with a speed of nanosecond time scale which is faster than speeds of electron releases from the crystal defects. These results strongly indicate that the nonvolatile memory characteristics of GaN/AlN RTDs are due to intersubband transitions and electron accumulation in the quantum well and are not attributed to electron trapping by the crystal defects.
Numerical study on flux-jump occurrence in a cup-shaped MgB2 bulk for magnetic shielding applications
Authors: Fracasso M , Gömöry F , Solovyov M , Gerbaldo R , Ghigo G , Laviano F , Sparacio S , Torsello D , Gozzelino L 
Published: February 2023

Abstract
MgB2 is one of the most promising materials for superconducting bulk applications. However, thermomagnetic instabilities can arise in the material because of its low heat capacity and thermal conductivity as well as its high critical current density. Being able to predict these phenomena, can guide and optimize MgB2-based devices for magnetic flux shielding or trapping applications. In this work, the flux-jump occurrence in an MgB2 cup-shaped shield is numerically studied using the finite element method by means of the commercial software COMSOL 6.0 Multiphysics®. To this aim, we developed a 2D axial-symmetric model coupling the heat diffusion equation and the magnetic equations based on a magnetic vector-potential (

A
⃗

) formulation. The comparison of the computed shielding curves with the experimental ones evidenced a good agreement between the two sets of data at different temperatures and positions along the shield’s axis. The as-validated model was then exploited to investigate possible optimization routes via the improvement of both the thermal conductivity of the material and the thermal exchange between the device and the cooling stage.
Near-isotropic enhancement of the 20 K critical current of REBa2Cu3O7 coated conductors from columnar defects
Authors: Strickland Nicholas M , Wimbush Stuart C , Soman Arya Ambadiyil , Long Nicholas J , Rupich Martin W , Knibbe Ruth , Li Ming , Notthoff Christian , Kluth Patrick 
Published: February 2023

Abstract
Normal-incidence irradiation by 100 MeV Ag ions is used to improve flux pinning in previously optimised commercial REBCO tapes from the American Superconductor Corporation. We observe distinct critical-current anisotropy enhancements below and above 40 K. Above 40 K a strong c-axis peak appears in the angular dependence of the critical current, as is usually expected upon the introduction of columnar defects. The critical current is enhanced significantly but only for a limited range of field angles. Close to the parallel-field direction there is no enhancement or even a reduction in critical current. Below 40 K, on the other hand, the enhancement is much broader with respect to field angle, creating an almost isotropic response at 20 K, 3 T. The absence of a prominent c-axis peak does not indicate a lack of pinning, since the absolute value of the critical current still increases by a factor of 2.8 compared to an unirradiated sample. Instead, we postulate that pre-existing point-like pinning centres act to mediate an interaction between the existing planar and newly-introduced columnar pins, broadening both contributions. The point-like pins become less effective with increasing temperature as the coherence length increases, leading to a reduction in this interaction and a separation of the individual peaks relating to planar and columnar pins. At 20 K, we achieve an enhancement in the angular-minimum critical current by a factor of 2.7, in a material that had already been process-optimised for low-temperature pinning.
Synthesis and modification of the structural, optical, and thermal properties of PVA–PEO by LDH nanoplates
Authors: Hosni N M , El-Sayed S , El Sayed Adel M , Saber S 
Published: February 2023

Abstract
Nanocomposites with thermal stability and tunable optical properties became essential for developed optoelectronic and electrochemical devices. This work represents an attempt to synthesize PVA–PEO polymeric blend and modifies its structural, optical, and thermal properties. This was performed by incorporating different ratios of double-layered hydroxide (Zn/Fe-LDH) nanoplates (NP) which were prepared by the co-precipitation process. XRD results revealed that the incorporation of LDH, 43 nm in size and rhombohedral phase, influenced the degree of crystallinity (X
C) of the blend. FE-SEM analysis showed the uniform distribution of LDH NP in the polymer matrix until 7.0 wt% content, beyond this ratio some voids were formed in the blend surface and particle agglomeration took place. FTIR spectroscopy illustrated the good miscibility of the polymers forming the blend, the interaction, and complexation between LDH NP and the blend functional groups. UV–vis-NIR spectroscopy analysis was performed to study the transmittance of the nanocomposites, extinction coefficient, refractive index, and optical conductivity. Besides, the direct and indirect band gaps of the films were found to decrease with increasing LDH NP content until a certain limit, after which they increased again. TGA&DSC analysis revealed the thermal stability of the films until 240 °C, and the DSC curves indicated three endothermic peaks. The obtained results confirmed that LDH NP incorporation is an interesting approach for tuning the optical and thermal properties to widen the technological applications based on PVA–PEO blend.
Localized wave solutions for (2+1)-dimensional third-order Fokou-Kofane-Mohamadou-Yomba equation
Authors: Fokou M , Kofane T C , Mohamadou A , Yomba E 
Published: February 2023

Abstract
Analytical and numerical investigations of localized wave solutions for a nonlinear evolution of shallow water waves with surface tension, which is described by the (2+1)-dimensional third-order Fokou-Kofane-Mohamadou-Yomba (FKMY) equation are performed. Furthermore, we show, mainly by Maple software and the Hirota bilinear method, that appropriated ansatzes can be used to generate new large families of traveling localized structures such as lump, soliton, periodic soliton, quasi-periodic soliton, and quasi-periodic breather solutions. Interactions between those soliton solutions and their dependence on the system physical parameters have been carefully analysed. We show that the soliton solutions of the 2D third-order FKMY display a very rich spectrum of dynamical behaviour when its parameters are varied. The present results could be applicable in explaining the basic features of localized disturbances in many fields of science where the 2D third-order FKMY equation appears.
Impact of the capture time on power saturation of quantum-well diode lasers
Authors: Boni A , Wenzel H , Crump P 
Published: February 2023

Abstract
Injected electrons and holes are captured into quantum wells with a non-vanishing time. Simulation results are presented, showing that this results in a non-equilibrium of free and bound carriers in a diode laser. Analysis of an exemplary diode laser structure is used to show that if the capture time is too large, the carrier densities in regions adjacent to the quantum well rise strongly beyond their values at threshold at very high output power. This results in an increase of the free carrier absorption and the non-stimulated recombination, causing a reduction of the slope efficiency and a downwards-bending of the power-current characteristics (power saturation), consistent with experimental results. For the layer structure studied, the additional losses due to accumulation of holes in the n-doped region is predicted to be the dominant effect.
Shaft inflation in Randall-Sundrum model
Authors: Loc Ngo Phuc Duc 
Published: February 2023

Abstract
Shaft inflation is a model in which the inflaton potential approaches a plateau far from
the origin, while it mimics chaotic inflation near the origin. Meanwhile, the Randall-Sundrum type
II model (RSII) is an interesting extra-dimensional model to study cosmological phenomenology. In
this paper, we study shaft inflation in the RSII model. We find that the predictions are in
excellent agreement with observation. The fundamental five-dimensional Planck scale is found to be
M
5 ≃ 1016 GeV, which is consistent with the lower bound M
5 ≳ 109 GeV obtained
from experimental Newtonian gravitational bound. This is an important result that can be used to explore further the implications of extra dimension in other contexts.
Compensation temperature and hysteresis behaviors of a graphene-like bilayer: Monte Carlo Study
Authors: Li Bo-chen , Lv Dan , Wang Wei , Sun Lei , Hao Zi-Ming , Bao Jia 
Published: February 2023

Abstract
Using the Monte Carlo method, the compensation temperature and hysteresis loops of a ferrimagnetic mixed spin-3/2 and spin-5/2 Ising-type graphene-like bilayer are investigated induced by different physical parameters such as crystal field, exchange coupling, external magnetic field, and temperature. The variations of magnetization, magnetic susceptibility, specific heat, and internal energy with the change of temperature are discussed. In addition, we also plot the phase diagrams including transition temperature and compensation temperature. Finally, multiple hysteresis loops under certain parameters are given.