bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamic model of the coupled valence and spin state transition in cobaltates
Authors: Hardy V , Bréard Y , Guillou F 
Published: November 2020

Abstract
A class of cobalt-based oxides exhibits a peculiar type of transition, entangling valence and spin state degrees of freedom of 4f and 3d elements. It constitutes one of the most spectacular illustrations of the interplay between charge, spin and lattice degrees of freedom in strongly correlated materials. In this work, we present a thermodynamic model capable to reproduce the main features of this transition. Our approach is based on the minimization of a free energy combining the contributions of two sublattices and the interaction between them. The coupling energies introduced in the model are related to well-known chemical pressure effects in the perovskite structure. The results of this model are compared to experimental data derived from x-ray absorption spectroscopy.
Numerical investigation of the effect of rate-sensitivity, non-octahedral slip and grain shape on texture evolution during hot rolling of aluminum alloys
Authors: Falkinger Georg , Mitsche Stefan 
Published: November 2020

Abstract
Based on texture simulations with a viscoplastic self-consistent polycrystal algorithm, this contribution presents a comprehensive investigation of the effect of the rate-sensitivity exponent, the relative strength of non-octahedral slip modes as well as the grain shape on texture evolution. The simulations are validated with texture measurements of samples from the industrial hot rolling process at different rolling reductions. Simulated textures at different hot rolling temperatures are compared with experimental findings from the literature. The present investigation indicates, that texture simulations must include three non-octahedral slip systems, use temperature dependent rate-sensitivity exponents and account for the evolution of grain shape.
Thermodynamic dislocation theory: application to bcc-crystals
Authors: Le K C , Dang S L , Luu H T , Gunkelmann N 
Published: November 2020

Abstract
This paper presents the thermodynamic dislocation theory containing several modifications over its first version which was originally proposed by Langer, Bouchbinder, and Lookman [5]. Employing a small set of physics-based material parameters identified by the large scale least squares analysis, we show that the theory can fit the stress–strain curves of bcc crystals niobium, tantalum, tungsten, and vanadium over a wide range of temperatures and strain rates.
Field-assisted growth of one-dimensional ZnO nanostructures with high defect density
Authors: Phuah Xin Li , Cho Jaehun , Akriti  , Dou Letian , Rheinheimer Wolfgang , García R Edwin , Zhang Xinghang , Wang Haiyan 
Published: November 2020

Abstract
One-dimensional ZnO nanostructures have shown great potential in electronics, optoelectronics and electromechanical devices owing to their unique physical and chemical properties. Most of these nanostructures were grown by equilibrium processes where the defects density is controlled by thermodynamic equilibrium. In this work, flash sintering, a non-equilibrium field-assisted processing method, has been used to synthesize ZnO nanostructures. By applying a high electric field and limiting a low current flow, ZnO nanorods grew uniformly by a vapor–liquid–solid mechanism due to the extreme temperatures achieved near the hot spot. High density basal stacking faults in the nanorods along with ultraviolet excitonic emission and a red emission under room temperature demonstrate the potential of defect engineering in nanostructures via the field-assisted growth method.
Thermoelectric properties of antimony selenide hexagonal nanotubes
Authors: Hernandez Jose A , Fonseca Luis F , Pettes Michael T , Jose-Yacaman Miguel 
Published: November 2020

Abstract
Antimony selenide (Sb2Se3) is a material widely used in photodetectors and relatively new as a possible material for thermoelectric applications. Taking advantage of the new properties after nanoscale fabrication, this material shows great potential for the development of efficient low temperature thermoelectric devices. Here we study the synthesis, the crystal properties and the thermal and thermoelectric transport response of Sb2Se3 hexagonal nanotubes (HNT) in the temperature range between 120 and 370 K. HNT have a moderate electrical conductivity ∼102 S m−1 while maintaining a reasonable Seebeck coefficient ∼430 μV K−1 at 370 K. The electrical conductivity in Sb2Se3 HNT is about 5 orders of magnitude larger and its thermal conductivity one half of what is found in bulk. Moreover, the calculated figure of merit (ZT) at room temperature is the largest value reported in antimony selenide 1D structures.
Investigation of electron transfer between single plasmon and graphene by dark field spectroscopy
Authors: Du Qian , Dou Zheng , Zhang Wenjia , Krüger Katja , Zhao Shuang , Yue Zhao , Liu Guohua 
Published: November 2020

Abstract
We investigated the electron transfer time between single plasmonic gold nanoparticles and graphene with our home-build spectral imaging dark-field microscope. The process of electron transfer is supposed to be shuttling of hot electrons on the nanoparticle-graphene interface, resulting in a slight broadening of the scattering spectrum. For detecting the minor spectrum broadening, we firstly characterized our setup systematically and then calibrated its intrinsic error. We found the mechanism of a common but normally neglected setup error, scattering spectrum broadening, which is caused by the bandwidth of the incident light and could exist in most fast dark-field microscopy setups. We corrected the linewidth of plasmon scattering spectra theoretically by both numerical and analytical solution, and then realized it experimentally by tuning the bandwidth of the incident light. After calibration, we revisited scattering spectra of 700 small aspect ratio nanorods on glass and monolayer graphene revealing a typical 14.3 meV linewidth broadening. Furthermore, we measured four other kinds of gold nanoparticles on glass, mono- and bilayer graphene for deeper understanding of the electron transfer. A common linewidth broadening is found for each kind of particle agreeing well with previous theory. However, an unconventional linewidth narrowing is also discovered for big particles whose resonance wavelength is close to the near infrared region. It implies a competitive mechanism in the electron transfer process which could not only increase the damping of small particles, causing a linewidth broadening, but also simplify the electric field pattern for big particles, leading to a linewidth narrowing, according to our Mie theory simulation.
Implementation of oxide vertical channel TFTs with sub-150 nm channel length using atomic-layer deposited IGZO active and HfO2 gate insulator
Authors: Ryoo Hyun-Joo , Seong Nak-Jin , Choi Kyu-Jeong , Yoon Sung-Min 
Published: November 2020

Abstract
We fabricated vertical channel thin film transistors (VTFTs) with a channel length of 130 nm using an ALD In–Ga–Zn–O (IGZO) active channel and high-k HfO2 gate insulator layers. Solution-processed SiO2 thin film, which exhibited an etch selectivity as high as 4.2 to drain electrode of indium-tin oxide, was introduced as a spacer material. For the formation of near-vertical sidewalls of the spacer patterns, the drain and spacer were successively patterned by means of two-step plasma etching technique using Ar/Cl2 and Ar/CF4 etch gas species, respectively. The SiO2 spacer showed smooth surface morphology (R
q = 0.45 nm) and low leakage current component of 10–6 A cm−2 at 1 MV cm−1, which were suggested to be appropriate for working as spacer and back-channel. The fabricated VTFT showed sound transfer characteristics and negligible shifts in threshold voltage against the bias stresses of +5 and −5 V for 104 s, even though there was abnormal increase in off-currents under the positive-bias stress due to the interactions between hydrogen-related defects and carriers. Despite the technical limitations of patterning process, our fabricated prototype IGZO VTFTs showed good operation stability even with an ultra-short channel length of 130 nm, demonstrating the potential of ALD IGZO thin film as an alternative channel for highly-scaled electronic devices.
Molten salt-confined pyrolysis towards carbon nanotube-backboned microporous carbon for high-energy-density and durable supercapacitor electrodes
Authors: Liu Siliang , Feng Qichun , Zhang Chao , Liu Tianxi 
Published: November 2020

Abstract
The development of a green and scalable construction of a three-dimensional (3D) hierarchically porous carbon as an electrode material for supercapacitors is promising but challenging. Herein, a carbon nanotube-backboned microporous carbon (CNT-MPC) was prepared by molten salt-confined pyrolysis, during which the salt eutectics simultaneously acted as a high-temperature reaction solvent and reusable template. Among the CNT-MPC, the CNT backbone provided a 3D conductive framework, whereas the MPC sheath possessed integrated mesopores and micropores as an efficient ion reservoir. As a result, the as-obtained CNT-MPC exhibited a high specific capacitance of 305.6 F g−1 at 1 A g−1, high energy density of 20.5 W h kg−1 and excellent cyclic stability with no capacitance losses after 50 000 cycles. The molten-salt confined pyrolysis strategy therefore provides a low-cost, environmentally-friendly and readily industrialized route to develop a hierarchically porous carbon that is highly required for high-energy-density and durable supercapacitors.
Out-of-field doses for scanning proton radiotherapy of shallowly located paediatric tumours—a comparison of range shifter and 3D printed compensator
Authors: Wochnik A , Stolarczyk L , Ambrožová I , Davídková M , De Saint-Hubert M , Domański S , Domingo C , Knežević Ž , Kopeć R , Kuć M , Majer M , Mojżeszek N , Mares V , Martínez-Rovira I , Caballero-Pacheco M Á , Pyszka E , Swakoń J , Trinkl S , Tisi M , Harrison R , Olko P 
Published: November 2020

Abstract
The lowest possible energy of proton scanning beam in cyclotron proton therapy facilities is typically between 60 and 100 MeV. Treatment of superficial lesions requires a pre-absorber to deliver doses to shallower volumes. In most of the cases a range shifter (RS) is used, but as an alternative solution, a patient-specific 3D printed proton beam compensator (BC) can be applied. A BC enables further reduction of the air gap and consequently reduction of beam scattering. Such pre-absorbers are additional sources of secondary radiation. The aim of this work was the comparison of RS and BC with respect to out-of-field doses for a simulated treatment of superficial paediatric brain tumours. EURADOS WG9 performed comparative measurements of scattered radiation in the Proteus C-235 IBA facility (Cyclotron Centre Bronowice at the Institute of Nuclear Physics, CCB IFJ PAN, Kraków, Poland) using two anthropomorphic phantoms—5 and 10 yr old—for a superficial target in the brain. Both active detectors located inside the therapy room, and passive detectors placed inside the phantoms were used. Measurements were supplemented by Monte Carlo simulation of the radiation transport. For the applied 3D printed pre-absorbers, out-of-field doses from both secondary photons and neutrons were lower than for RS. Measurements with active environmental dosimeters at five positions inside the therapy room indicated that the RS/BC ratio of the out-of-field dose was also higher than one, with a maximum of 1.7. Photon dose inside phantoms leads to higher out-of-field doses for RS than BC to almost all organs with the highest RS/BC ratio 12.5 and 13.2 for breasts for 5 and 10 yr old phantoms, respectively. For organs closest to the isocentre such as the thyroid, neutron doses were lower for BC than RS due to neutrons moderation in the target volume, but for more distant organs like bladder—conversely—lower doses for RS than BC were observed. The use of 3D printed BC as the pre-absorber placed in the near vicinity of patient in the treatment of superficial tumours does not result in the increase of secondary radiation compared to the treatment with RS, placed far from the patient.
A digital phoswich detector using time-over-threshold for depth of interaction in PET
Authors: Prout David L , Gu Zheng , Shustef Max , Chatziioannou Arion F 
Published: November 2020

Abstract
We present the performance of a digital phoswich positron emission tomography (PET) detector, composed by layers of pixilated scintillator arrays, read out by solid state light detectors and an application specific integrated circuit (ASIC). We investigated the use of integrated charge from the scintillation pulses along with time-over-threshold (ToT) to determine the layer of interaction (DOI) in the scintillator. Simulations were performed to assess the effectiveness of the ToT measurements for separating the scintillator events and identifying cross-layer-crystal-scatter (CLCS) events. These simulations indicate that ToT and charge integration from such a detector provide sufficient information to determine the layer of interaction. To demonstrate this in practice, we used a pair of prototype LYSO/BGO detectors. One detector consisted of a 19 × 19 array of 7 mm long LYSO crystals (1.36 mm pitch) coupled to a 16 × 16 array of 8 mm long BGO crystals (1.63 mm pitch). The other detector was similar except the LYSO crystal pitch was 1.63 mm. These detectors were coupled to an 8 × 8 multi-pixel photon counter mounted on a PETsys TOFPET2 ASIC. This high performance ASIC provided digital readout of the integrated charge and ToT from these detectors. We present a method to separate the events from the two scintillator layers using the ToT, and also investigate the performance of this detector. All the crystals within the proposed detector were clearly resolved, and the peak to valley ratio was 11.8 ± 4.0 and 10.1 ± 2.9 for the LYSO and BGO flood images. The measured energy resolution was 9.9% ± 1.3% and 28.5% ± 5.0% respectively for the LYSO and BGO crystals in the phoswich layers. The timing resolution between the LYSO–LYSO, LYSO–BGO and BGO–BGO coincidences was 468 ps, 1.33 ns and 2.14 ns respectively. Results show ToT can be used to identify the crystal layer where events occurred and also identify and reject the majority of CLCS events between layers.
Inferring the flow properties of epithelial tissues from their geometry
Authors: Popović Marko , Druelle Valentin , Dye Natalie A , Jülicher Frank , Wyart Matthieu 
Published: November 2020

Abstract
Amorphous materials exhibit complex material properties with strongly nonlinear behaviors. Below a yield stress they behave as plastic solids, while they start to yield above a critical stress Σc. A key quantity controlling plasticity which is, however, hard to measure is the density P(x) of weak spots, where x is the additional stress required for local plastic failure. In the thermodynamic limit P(x) ∼ x

θ
is singular at x = 0 in the solid phase below the yield stress Σc. This singularity is related to the presence of system spanning avalanches of plastic events. Here we address the question if the density of weak spots and the flow properties of a material can be determined from the geometry of an amorphous structure alone. We show that a vertex model for cell packings in tissues exhibits the phenomenology of plastic amorphous systems. As the yield stress is approached from above, the strain rate vanishes and the avalanches size S and their duration τ diverge. We then show that in general, in materials where the energy functional depends on topology, the value x is proportional to the length L of a bond that vanishes in a plastic event. For this class of models P(x) is therefore readily measurable from geometry alone. Applying this approach to a quantification of the cell packing geometry in the developing wing epithelium of the fruit fly, we find that in this tissue P(L) exhibits a power law with exponents similar to those found numerically for a vertex model in its solid phase. This suggests that this tissue exhibits plasticity and non-linear material properties that emerge from collective cell behaviors and that these material properties govern developmental processes. Our approach based on the relation between topology and energetics suggests a new route to outstanding questions associated with the yielding transition.
Efficient implementation of complete and nondestructive Bell-state measurement for trapped ions with reverse engineering
Authors: Ning Yu , Kang Yi-Hao , Shi Zhi-Cheng , Song Jie , Xia Yan 
Published: November 2020

Abstract
In this paper, we put forward a protocol for the complete and nondestructive Bell-state measurement of trapped ions. We show that the four different Bell states of two information carriers can be distinguished using two auxiliary ions with the initial Bell states unchanged after the procedures. The parameter selections are discussed based on the experimentally available parameters, and the robustness against the errors and decoherence are analyzed. The results show that the protocol works well with the selected parameters, and possesses robustness against errors and decoherence. Since the laser pulses to drive the transitions of ions in the procedures are designed via reverse engineering, the control parameters can be flexibly selected under certain boundary conditions, which provides the possibility to find corrective parameters to compensate the errors caused by the decoherence. We hope the protocol can be useful for the Bell-state based quantum information tasks.
Boosting template-based SSVEP decoding by cross-domain transfer learning
Authors: Chiang Kuan-Jung , Wei Chun-Shu , Nakanishi Masaki , Jung Tzyy-Ping 
Published: November 2020

Abstract

Objective. This study aims to establish a generalized transfer-learning framework for boosting the performance of steady-state visual evoked potential (SSVEP)-based brain–computer interfaces (BCIs) by leveraging cross-domain data transferring. Approach. We enhanced the state-of-the-art template-based SSVEP decoding through incorporating a least-squares transformation (LST)-based transfer learning to leverage calibration data across multiple domains (sessions, subjects, and electroencephalogram montages). Main results. Study results verified the efficacy of LST in obviating the variability of SSVEPs when transferring existing data across domains. Furthermore, the LST-based method achieved significantly higher SSVEP-decoding accuracy than the standard task-related component analysis (TRCA)-based method and the non-LST naive transfer-learning method. Significance. This study demonstrated the capability of the LST-based transfer learning to leverage existing data across subjects and/or devices with an in-depth investigation of its rationale and behavior in various circumstances. The proposed framework significantly improved the SSVEP decoding accuracy over the standard TRCA approach when calibration data are limited. Its performance in calibration reduction could facilitate plug-and-play SSVEP-based BCIs and further practical applications.
Influence of pollen source in some qualitative characteristics of date palm fruits propagated by offshoots and tissue culture techniques
Authors: Ameer Abeed Nada Abdel , Taain Dhia Ahmed , Hamza Hamza Abbas 
Published: November 2020

Abstract
The current study was carried out in the private orchard in Kitiabn region in Basrah governorate to study the effect of two male cultivars ( Ghanamy akhdar, Khikri adi) and two methods of date palm propagation (offshoots and tissue culture techniques) on physico-chemical characteristics of date palm fruits during the developing stages (Habbabuk, Kimri and Khalal). Twelve trees of the Barhi cultivar were selected as similar as possible in age (5 years), growth and had the same agricultural practices. Six flower clusters (spadix) were selected from each tree and removed the rest. An experiment was designed according to Randomized Block Design (RCBD) with three replicates and the mean differences were compared by using the least significant difference (L.S.D) test at the probability level of 0.05. Results showed that Barhi date palm pollinated with Khikri adi pollen grains and propagated by offshoots were superior in the most studied characteristics at habbabuk stage. At Kimri stage, the date palms propagated by offshoots and pollinated with Ghanamy akhdar was the best in the most studied characteristics, while at Khalal stage results indicated to the superiority of Ghanamy akhdar pollen grains and tissue culture techniques method in most of the physico-chemical characteristics.
Antimicrobial activity of liquid residues of Cymbopogon citratus oil extracts
Authors: Mohammed Taghreed K , Aqel Nahla , Al-Dujaili Emad A S 
Published: November 2020

Abstract
Cymbopogon citratus (Lemongrass) is a type of medicinal herb that widely used in Asia. This study aims to investigate the antimicrobial activity of liquid residues of ethanolic and aqueous Cymbopogon citratus oil extracts. Residues of ethanolic and aqueous Cymbopogon citratus oil extracts were used to study their antimicrobial activities for Staphylococcus aureus; Staphylococcus epidermidis; Pseudomonas aeruginosa and Candida albicans which were isolated from burned skin of patients suffering from burns at Medical City Hospital/Specialist burns Unit/Baghdad. Minimum inhibitory concentration and minimum bactericidal concentration were measured for all microorganisms using microtitre plates and Resazurin dye by a spectrophotometer at 517 nm. The components of liquid residues were detected by phytochemical tests; and the concentrations of Iodine were determined by Ion Chromatography. The antioxidant activity was measured by using DPPH method. The liquid residues of ethanolic and aqueous extracts of Lemongrass showed antimicrobial effect against all the test microorganisms including Pseudomonas aeruginosa. The ethanolic extraction of Cymbopogon citratus contain Alkaloids, Flavonoids, Glycosides, Phenols, Saponins, Terpenes, Tannins, Fatty acids and Couarins, but no Seroids, volatile oil and Emodins. The Minimum Inhibitory Concentrations of ethanolic extract for Staphylococcus aureus; Staphylococcus epidermidis; Pseudomonas aeruginosa and Candida albicans were 12.5, 12.5, 12.5 and 25µl/mL respectively. The extracts of lemongrass residues due to their phytochemical contents and pharmacological activity seem to be highly effective against some pathogenic microorganisms in the inflamed skin. It can be suggested that these extracts may be used for skin treatment in burned patients infected with pathogenic microorganisms.