bluuebunny/crossref_metadata_2025 huggingface dataset:
A gram-scale fabrication of core–shell copper nanoparticles for efficient hydrogenation of nitroarenes
Authors: Yun Ruirui , Zhang Wei , Zhang Zan , Zhang Xiaoxuan , Wang Zhaoxu , Luo Shizhong
Published: August 2022

Herein, a series of core–shell catalysts (defined as Cu@NC/PC) has been designed and synthesized for the first time using a functional polymer assistant strategy.
Vapor-phase synthesis of a reagent-free self-healing polymer film with rapid recovery of toughness at room temperature and under ambient conditions
Authors: Jeong Kihoon , Kwak Moo Jin , Kim Youson , Lee Youjin , Mun Hyeonwoo , Kim Min Ju , Cho Byung Jin , Choi Siyoung Q. , Im Sung Gap
Published: August 2022

A rapidly self-healable polymer was synthesized via iCVD process, and this polymer showed rapid recovery of mechanical properties in the ambient condition.
Fluid interface-assisted assembly of soft microgels: recent developments for structures beyond hexagonal packing
Authors: Feller Déborah , Karg Matthias
Published: August 2022

Microgels can be assembled into 2-dimensional monolayers featuring microstructures beyond hexagonal packing. We review recent assembly strategies – all involving adsorption to fluid interfaces with control over surface pressure.
Confinement catalysis of a single atomic vacancy assisted by aliovalent ion doping enabled efficient NO electroreduction to NH3
Authors: He Bingling , Lv Peng , Wu Donghai , Li Xue , Zhu Rui , Chu Ke , Ma Dongwei , Jia Yu
Published: August 2022

The confinement catalysis of a single atom vacancy (SAV) assisted by aliovalent ion doping is proposed for selective and direct electrocatalytic NO reduction to produce NH3.
Study of the doping effect on imperfect morphology at photovoltaic heterojunctions in bilayer organic solar cells
Authors: Chen Zhenyu , Zheng Hong , Ma Wei , Yan Han
Published: August 2022

The efficient doping of a donor–acceptor copolymer is controlled by the charge–quadrupole interaction between the dopant and the respective units to improve the photovoltaic performance by alleviating the energy barrier for charge separation.
Synthesis of ultra-high specific surface area aerogels with nitrogen-enriched Ti3C2Tx nanosheets as high-performance supercapacitor electrodes
Authors: Liu Xudong , Liu Yong , Dong Shangli , Zhang Xuefeng , Hou Shida
Published: August 2022

A novel combination method for nitrogen doping and 3D structure construction is explored to prepare nitrogen-doped Ti3C2Tx aerogels. The synergistic effects of nitrogen doping and 3D structure construction on Ti3C2Tx are analyzed.
Fabrication, material regulation, and healthcare applications of flexible photodetectors
Authors: Jiang Ya , Zhang Xiaoyuan , Wei Gang , Su Zhiqiang
Published: August 2022

We present the recent advances in the fabrication methods, materials for regulation, and applications of flexible photodetectors.
A nonlinear adaptive excitation controller design for two‐axis models of synchronous generators in multimachine power systems to augment the transient stability during severe faults
Authors: Roy Tushar Kanti , Mahmud Md Apel
Published: August 2022

This paper presents an excitation controller design process for multimachine power systems with synchronous generators using an adaptive backstepping approach to ensure robust performance against parametric uncertainties as well as to improve the transient stability during large disturbances. In this work, electrical dynamics of synchronous generators are described using two‐axis models while excitations systems are represented as the IEEE Type II exciter which mainly captures electrical dynamics while swing equations are used to capture mechanical dynamics. The proposed adaptive backstepping control approach is then employed to derive the excitation control law. The proposed adaptive backstepping scheme uses all nonlinearities, which are mainly due to the interconnections and rotations of rotors in synchronous generators, within the dynamical models to improve the transient stability during severe disturbances. Furthermore, this excitation control scheme uses estimated values of parameters appearing in the dynamical models of power system which are estimated using adaptation laws based on real‐time measurements and hence, it provides robustness against parametric uncertainties. The theoretical stability of the proposed scheme is assessed using the Lyapunov stability theory, that is, by checking the negative definiteness or semi‐definiteness of the derivative of control Lyapunov functions (CLFs). Rigorous simulations are conducted on an IEEE 39‐bus 10‐machine test power system for evaluating the performance of the proposed scheme under different operating conditions. Simulation results clearly demonstrate the superiority of the adaptive backstepping excitation controller over existing nonlinear controllers including an existing adaptive backstepping excitation controller that is designed using the classical model of synchronous generators.
The stable climate of KELT-9b
Authors: Jones K. , Morris B. M. , Demory B.-O. , Heng K. , Hooton M. J. , Billot N. , Ehrenreich D. , Hoyer S. , Simon A. E. , Lendl M. , Demangeon O. D. S. , Sousa S. G. , Bonfanti A. , Wilson T. G. , Salmon S. , Csizmadia Sz. , Parviainen H. , Bruno G. , Alibert Y. , Alonso R. , Anglada G. , Bárczy T. , Barrado D. , Barros S. C. C. , Baumjohann W. , Beck M. , Beck T. , Benz W. , Bonfils X. , Brandeker A. , Broeg C. , Cabrera J. , Charnoz S. , Collier Cameron A. , Davies M. B. , Deleuil M. , Deline A. , Delrez L. , Erikson A. , Fortier A. , Fossati L. , Fridlund M. , Gandolfi D. , Gillon M. , Güdel M. , Isaak K. G. , Kiss L. L. , Laskar J. , Lecavelier des Etangs A. , Lovis C. , Magrin D. , Maxted P. F. L. , Nascimbeni V. , Olofsson G. , Ottensamer R. , Pagano I. , Pallé E. , Peter G. , Piotto G. , Pollacco D. , Queloz D. , Ragazzoni R. , Rando N. , Ratti F. , Rauer H. , Reimers C. , Ribas I. , Santos N. C. , Scandariato G. , Ségransan D. , Smith A. M. S. , Steller M. , Szabó Gy. M. , Thomas N. , Udry S. , Van Grootel V. , Walter I. , Walton N. A. , Wang Jungo W.
Published: August 2022

Even among the most irradiated gas giants, so-called ultra-hot Jupiters, KELT-9b stands out as the hottest planet thus far discovered with a dayside temperature of over 4500 K. At these extreme irradiation levels, we expect an increase in heat redistribution efficiency and a low Bond albedo owed to an extended atmosphere with molecular hydrogen dissociation occurring on the planetary dayside. We present new photometric observations of the KELT-9 system throughout 4 full orbits and 9 separate occultations obtained by the 30 cm space telescope CHEOPS. The CHEOPS bandpass, located at optical wavelengths, captures the peak of the thermal emission spectrum of KELT-9b. In this work we simultaneously analyse CHEOPS phase curves along with public phase curves from TESS and Spitzer to infer joint constraints on the phase curve variation, gravity-darkened transits, and occultation depth in three bandpasses, as well as derive 2D temperature maps of the atmosphere at three different depths. We find a day-night heat redistribution efficiency of ~0.3 which confirms expectations of enhanced energy transfer to the planetary nightside due to dissociation and recombination of molecular hydrogen. We also calculate a Bond albedo consistent with zero. We find no evidence of variability of the brightness temperature of the planet, excluding variability greater than 1%
Le registre national des calpaïnopathies
Authors: Richard Isabelle , Simental Emmanuel , Malfatti Edoardo , Staelens Caroline , Eng Catherine
Published: August 2022

Les calpaïnopathies sont des maladies génétiques associées à des mutations autosomiques récessives (LGMD-R1), ou beaucoup plus rarement dominantes (LGMD-D4), du gène CAPN3 codant la calpaïne-3. Les patients souffrent d’une myopathie des ceintures lentement progressive. Sur la base d’une prévalence estimée de 10 à 70 par million d’habitants, il existerait en France entre 670 et 4 200 individus atteints de calpaïnopathie. Sous l’impulsion du groupe d’intérêt sur les calpaïnopathies de la filière nationale de santé FILNEMUS, et compte tenu de la planification des futurs essais cliniques dans cette pathologie, un registre national des calpainopathies a été créé grâce au soutien de l’AFM-Téléthon. L’objectif du registre est de colliger les données des patients, de décrire l’histoire naturelle de la maladie, d’optimiser le parcours de soin et d’accélérer la conception et le déroulement des essais cliniques.
The existence of path-factor uniform graphs with large connectivity
Authors: Zhou Sizhong , Bian Qiuxiang
Published: August 2022

A path-factor is a spanning subgraphFofGsuch that every component ofFis a path with at least two vertices. Letk ≥ 2 be an integer. AP≥k-factor ofGmeans a path factor in which each component is a path with at leastkvertices. A graphGis aP≥k-factor covered graph if for anye ∈ E(G),Ghas aP≥k-factor coveringe. A graphGis called aP≥k-factor uniform graph if for anye1, e2 ∈ E(G) withe1 ≠ e2,Ghas aP≥k-factor coveringe1and avoidinge2. In other words, a graphGis called aP≥k-factor uniform graph if for anye ∈ E(G),G − eis aP≥k-factor covered graph. In this paper, we present two sufficient conditions for graphs to beP≥3-factor uniform graphs depending on binding number and degree conditions. Furthermore, we show that two results are best possible in some sense.
Kutane Nebenwirkungen unter
Immun-Checkpoint-Inhibitor-Therapie
Authors: Grän Franziska , Schilling Bastian
Published: August 2022

Moderne Immuntherapeutika wie Nivolumab, Pembrolizumab oder Ipilimumab, die
sogenannte Immun-Checkpoints blockieren, haben die onkologische Therapie in den
letzten Jahren revolutioniert. Mit dem neuen Wirkmechanismus der Blockade
wichtiger Kontrollpunkte im Immunsystem zeigen sich jedoch auch eine Vielzahl an
unterschiedlichen Nebenwirkungen. Diese treten nicht selten an der Haut auf. Zu
den häufigsten dermalen Reaktionen unter Immuntherapie zählen
die Vitiligo, Exantheme, blasenbildende Reaktionen oder der Lichen planus.
Ausgeprägter Juckreiz kann Patienten stark beeinträchtigen. Der
Verlauf bei auf die Haut beschränkten Nebenwirkungen ist häufig
mild und gut zu behandeln oder selbstlimitierend. Hauterscheinungen
können jedoch auch als Symptom systemischer Reaktionen auftreten. Eine
frühe Diagnosestellung, die Einleitung einer adäquaten Therapie
sowie eine interdisziplinäre Betreuung bei komplexen Erkrankungen sind
entscheidend, um dauerhafte Einschränkungen für die Patienten zu
verhindern und eine sichere Behandlung der zugrundeliegenden Tumorerkrankung
gewährleisten zu können.
Entwicklung der universitären palliativmedizinischen Lehre in Österreich: ein Scoping Review
Authors: Toussaint Véronique , Elsner Frank , Paal Piret
Published: August 2022

Ziel der Studie Die Integration von Palliative Care in die universitäre Lehre ist ein wichtiger Schritt, um die Palliativversorgung in Österreich zu stärken. Ziel dieses Scoping Reviews ist die Identifikation und Darstellung der Literatur, die sich mit der palliativmedizinischen Lehre an österreichischen Universitäten beschäftigt.

Methodik Im Mai und November 2021 wurden nach den Guidelines von JBI und PRISMA-ScR mehrere Literaturrecherchen in den Datenbanken PubMed und Web of Science Core Collection durchgeführt. Um umfassendere Ergebnisse zu erzielen, wurden weitere relevante Artikel in zusätzlichen Quellen identifiziert.

Ergebnisse Es konnten 15 Artikel eingeschlossen werden. Sowohl zur Anzahl der österreichischen Universitäten mit einem palliativmedizinischen Lehrangebot als auch zur Qualität dieser Lehre konnten unterschiedliche Angaben herausgestellt werden.

Schlussfolgerung Derzeit ist die palliativmedizinische Lehre an österreichischen Universitäten nur unzureichend erfasst.
Premedication with simethicone for improving the quality of gastric mucosal visualization: a double-blind randomized controlled trial
Authors: Duez Leo , Gkolfakis Paraskevas , Bastide Marine , Vuckovic Clemence , Musala Carmen , Van Gossum Marc , Hoyois Alice , Mulkay Jean-Pierre , Eisendrath Pierre
Published: August 2022

Background and study aims Saliva, bubbles, or mucus can limit gastric mucosal visualization (GMV), increasing the risk of missed lesions such as gastric cancer. Several studies using endoscopy photodocumentation-based scores have reported increased quality of GMV when mucolytic and/or defoaming agents are administered. This single-center, prospective, double-blind, randomized, placebo-controlled trial aimed to evaluate whether simethicone administration could improve GMV.

Patients and methods Patients were randomly assigned (1:1) to receive either 200 mg of simethicone (Group A) or placebo (Group B). Two independent endoscopists reviewed the entire video recording from each examination to assess the quality of GMV. The primary outcome was the rate of adequate GMV, defined as the percentage of patients in each group with a video score scale < 7 based on gastric visualization of five gastric landmarks. Secondary outcomes included procedure duration, patient satisfaction, and side effects.

Results A total of 110 consecutive outpatients were randomly assigned to one of the two study groups (11 were excluded for various reasons). For the primary endpoint, 32 patients (61.5 %) in group A achieved adequate GMV compared to one of 47 (2.1 %) in group B (odds ratio [95 % confidence interval]: 73.6 [9.4–576.6]; P < 0.001). Median procedure time did not differ between the groups (P = 0.55), and no differences were detected in patient satisfaction (P = 0.18) or side effects (P = 0.58). No serious adverse events were documented.

Conclusions Premedication with simethicone before upper gastrointestinal endoscopy significantly improves the quality of GMV without affecting the duration of the examination, patient satisfaction, and the rate of side effects.
Introduction of endoscopic ultrasound-guided hepaticoenterostomy – experience from a general hospital in Japan
Authors: Kaneko Toru , Kida Mitshiro , Kitahara Gen , Uehara Kazuho , Koyama Shiori , Tachikawa Satsuki , Watanabe Masaaki , Kusano Chika
Published: August 2022

Background and study aims Endoscopic ultrasound-guided biliary drainage (EUS-BD) is a widely used alternative to endoscopic retrograde cholangiopancreatography (ERCP) when ERCP is unsuccessful or there are contraindications such as duodenal stenosis or postsurgical intestinal reconstruction. Therefore, we retrospectively investigated the therapeutic outcomes of EUS-BD in a medium-sized hospital.

Patients and methods We included 31 consecutive patients who underwent EUS-BD at the Kitasato University Medical Center between April 2018 and October 2021. Patient characteristics, technical and clinical success rates, stent patency, adverse events (AEs), and procedure time were analyzed.

Results Of the 31 patients included in this study, one underwent endoscopic ultrasound-guided choledochoduodenostomy (EUS-CDS) and 30 underwent endoscopic ultrasound-guided hepaticoenterostomy (EUS-HES). The technical success rates were 100 % for EUS-CDS and 96.8 % for EUS-HES because EUS-HES was unsuccessful in one patient who then underwent EUS-CDS as an alternative treatment. The clinical success rates were 100 % for EUS-CDS and 96.7% for EUS-HES. The median follow-up period was 84 days (range: 14–483 days). Zero and 5 (16.6 %) patients who underwent EUS-CDS and EUS, respectively had stent dysfunction. The median stent patency (stent dysfunction and death) for EUS-HES was 124 days. AEs were observed in only two patients (6.7 %) who underwent EUS-HES.

Conclusions EUS-BD is now more widely used than before, and advances in the devices used have enabled the procedure to be performed more safely. Our results suggest that this introduction in medium-sized hospitals can be conducted safely.
Intramuscular Microvascular Flow Sensing for Flap Monitoring in a Porcine Model of Arterial and Venous Occlusion
Authors: Lu Di , Moritz William , Arafa Hany M. , Yang Quansan , Jacobson Lauren , Ostojich Diana , Bai Wubin , Guo Hexia , Wu Changsheng , Li Shuo , Li Shupeng , Huang Yonggang , Xu Yameng , Yan Ying , Westman Amanda M. , MacEwan Matthew R. , Rogers John A. , Pet Mitchell A.
Published: August 2022

Background Commercially available near infrared spectroscopy devices for continuous free flap tissue oxygenation (StO2) monitoring can only be used on flaps with a cutaneous component. Additionally, differences in skin quality and pigmentation may alter StO2 measurements. Here, we present a novel implantable heat convection probe that measures microvascular blood flow for peripheral monitoring of free flaps, and is not subject to the same issues that limit the clinical utility of near-infrared spectroscopy.

Methods The intratissue microvascular flow-sensing device includes a resistive heater, 4 thermistors, a small battery, and a Bluetooth chip, which allows connection to a smart device. Convection of applied heat is measured and mathematically transformed into a measurement of blood flow velocity. This was tested alongside Vioptix T.Ox in a porcine rectus abdominis myocutaneous flap model of arterial and venous occlusion. After flap elevation, the thermal device was deployed intramuscularly, and the cutaneous T.Ox device was applied. Acland clamps were alternately applied to the flap artery and veins to achieve 15 minutes periods of flap ischemia and congestion with a 15 minutes intervening recovery period. In total, five devices were tested in three flaps in three separate pigs over 16 vaso-occlusive events.

Results Flow measurements were responsive to both ischemia and congestion, and returned to baseline during recovery periods. Flow measurements corresponded closely with measured StO2. Cross-correlation at zero lag showed agreement between these two sensing modalities. Two novel devices tested simultaneously on the same flap showed only minor variations in flow measurements.

Conclusion This novel probe is capable of detecting changes in tissue microcirculatory blood flow. This device performed well in a swine model of flap ischemia and congestion, and shows promise as a potentially useful clinical tool. Future studies will investigate performance in fasciocutaneous flaps and characterize longevity of the device over a period of several days.
Intraoperative Heparin Bolus and Postoperative Anticoagulation with Low Molecular Weight Heparin Increase Reliability of Microsurgical Free Flaps for Upper Extremity Reconstruction
Authors: Kallenberger Ann-Katrin , Xiong Lingyun , Gazyakan Emre , Ziegler Benjamin , Will Patrick , Kneser Ulrich , Hirche Christoph
Published: August 2022

Background Microsurgery is an indispensable tool of upper extremity reconstruction addressing defect coverage and the restoration of function. Perioperative anticoagulation and antiplatelet therapy are controversially discussed with impact on microsurgical outcome, but without clear evidence. This study aims to evaluate the impact of perioperative anticoagulation and antiplatelet therapy in microsurgical upper extremity reconstruction.

Methods All eligible patients treated with microsurgical upper extremity reconstruction between January 2000 and July 2014 were included in a comparative analysis to define a superior anticoagulation and antiplatelet regime in a retrospective study. Endpoints were all major complications (e.g., total flap loss, arterial and venous thrombosis) as well as minor complication.

Results A total of 183 eligible free flaps to the upper extremity were transferred in 169 patients. Altogether, 11 arterial (6.0%) and 9 venous (4.9%) thromboses, 11 total flap losses (6.0%), and 16 cases with hematoma (8.7%) were detected. In the subgroup analysis, patients who did not receive any heparin intraoperatively (n = 21; 11.5%) had a higher rate of major complications (p = 0.001), with total flap loss being the most frequent event (p = 0.004). A trend was shown for intraoperative bolus administration of 501 to 1,000 units unfractionated heparin (UFH) intravenously to have the lowest rate of major complications (p = 0.058). Intraoperative administration of acetylsalicylic acid (n = 13; 8.1%) did not have any influence on the rate of major complications. Postoperative anticoagulation with continuous UFH intravenously (n = 68; 37.2%) resulted in more frequent complications (p = 0.012), for example, an increased rate of total flap loss (p = 0.02) and arterial thrombosis (p = 0.02).

Conclusion The results of the present study favor administration of 501 to 1,000 units UFH intravenously as an intraoperative bolus (e.g., 750 units UFH intravenously). Postoperative low molecular weight heparin subcutaneous application in a prophylactic dose given once or twice a day was associated with less complications compared with continuous infusion of UFH, although continuously applied UFH may reflect an increased risk profile.
Phenomenological statistics of diluted charged solutions (Review Article)
Authors: Chikina I.
Published: August 2022

The consistent interpretation of the equilibrium and simplest transport properties of diluted liquid electrolytes, the normal and cryogenic ones, by analogy with the observed consequences of electron-hole statistics in crystalline semiconductors is proposed. The consideration is based on the micro characteristics of individual charged clusters, introduced phenomenologically, such as their energies, effective masses, etc. The possibilities of extracting these parameters from the available experimental data are discussed in detail. This is crucial for explaining the very possibility of the statistical consideration of what is unfolding in electrolytes. A deep analogy between the statistics of electrolytes and that of solid-state semiconductors is noted. Its presence is the basis of the phenomenology being developed.
X-ray diffraction imaging of the diamond anvils based on the microfocus x-ray source with a liquid anode
Authors: Barannikov Aleksandr , Troyan Ivan , Snigireva Irina , Snigirev Anatoly
Published: August 2022

This paper presents the results of using laboratory x-ray systems in the study of the crystal structure of anvil made from single-crystal diamond. The system is equipped with an Excillum MetalJet D2 + 70 kV high-brightness x-ray source with a liquid GaIn anode. The x-ray diffraction imaging (topography) technique with the use of a high-resolution x-ray Rigaku camera was applied to analyze crystal structure defects. Two-dimensional images were experimentally recorded using 400 and 111 reflections with a resolution of 1.5 and 5 μm, respectively. These topograms displayed various defects, such as growth striations and dislocations. Possible applications of the proposed laboratory-based optical scheme for high-pressure physics are discussed and future improvements to the setup are suggested.
Fluorescence-enhanced Si photodiodes for ultraviolet C rays (UVC) measurements
Authors: Katsumata Toru , Hitomi Ami , Narita Ryuhei , Nakamizo Akiho , Shirako Takahiro , Nakano Sae , Hosoya Sattawat , Yamazaki Manami , Aizawa Hiroaki
Published: August 2022

The ultraviolet C rays (UVC, wavelength λ = 100–280 nm) light generated by a Hg lamp (λ = 254 nm) and UVC light-emitting diodes (LEDs, λ = 265 and 275 nm) was detected using a fluorescence-enhanced silicon photodiode (FE-PD). Ce-doped yttrium aluminum garnet (YAG:Ce), YAG:Pr, YAG:Eu, YAG:Tb, YAG:Cr, Al2O3:Ti, Al2O3:Cr, MgAl2O4:Ti, MgAl2O4:Cr, MgAl2O4:Mn, and commercial fluorescent acrylic resins were tested as phosphor sources to enhance the output signal intensity of the FE-PD irradiated with UVC light. The resulting output signal intensity increased linearly with the UVC light strength, which was adjusted by raising the input current of the UVC LEDs from 0 to 40 mA. The sensitivity of the fabricated UVC detectors, assessed based on the calibration curve slope, varied depending on the phosphor materials. The phosphors effectively enhanced the output signal intensity of the FE-PD, which was up to six times greater than that of the visible and near infrared Si-PD without phosphors; the stronger output signal intensity was achieved using YAG:Tb, YAG:Cr, and a red fluorescent acrylic resin. The visible light emitted by phosphors under UVC irradiation is useful for detecting UVC light by the eye when using FE-PD.
Sub-millinewton thrust stand and wireless power coupler for microwave-powered small satellite thrusters
Authors: Wachs Benjamin N. , Jorns Benjamin A.
Published: August 2022

The design and performance of a thrust stand for characterizing low-power electric propulsion thrusters are presented. The thrust stand is capable of sub-millinewton resolution for devices on the order of 1 kg. The architecture is based on a counter-weighted hanging pendulum design, a variant of the standard hanging pendulum that employs a counterweight to increase force resolution. Thrust is measured in a displacement mode using the change in position of the pendulum arm as measured by an optical displacement sensor. Passive eddy-current damping is used to offset oscillations and decrease setting time. An in situ calibration rig using known masses is used to calculate thrust. The thrust stand features an adjustable counterweight for in-vacuum sensitivity adjustment. In addition, the design of a broadband (600–2490 MHz) wireless microwave power coupler is presented. The device eliminates stiffness and thermal drift introduced by coaxial cables—typically the leading source of error in testing low-power microwave and radio frequency-powered thrusters. The thrust stand and coupler were tested using an electron cyclotron resonance magnetic nozzle thruster operating with xenon at flow rates from 1 to 10 sccm and powers ranging from zero (cold gas thrust) to 40 W. The resulting measurements showed a force resolution of ∼10μN over a range of thrusts from ∼14 to 600 µN.
Heavy ion irradiation induced phase transitions and their impact on the switching behavior of ferroelectric hafnia
Authors: Lederer Maximilian , Vogel Tobias , Kämpfe Thomas , Kaiser Nico , Piros Eszter , Olivo Ricardo , Ali Tarek , Petzold Stefan , Lehninger David , Trautmann Christina , Alff Lambert , Seidel Konrad
Published: August 2022

The discovery of ferroelectric hafnium oxide enabled a variety of non-volatile memory devices, like ferroelectric tunnel junctions or field-effect transistors. Reliable application of hafnium oxide based electronics in space or other high-dose environments requires an understanding of how these devices respond to highly ionizing radiation. Here, the effect of 1.6 GeV Au ion irradiation on these devices is explored, revealing a reversible phase transition, as well as a grain fragmentation process. The collected data demonstrate that non-volatile memory devices based on ferroelectric hafnia layers are ideal for applications where excellent radiation hardness is mandatory.
Experimental investigation of combustion-induced starting hysteresis in the scramjet
Authors: Zhang Qifan , Chen Hao , Wu Zhenjie , Gao Zhanbiao , Luo Weihang , Gu Hongbin , Yue Lianjie
Published: August 2022

Understanding the hypersonic inlet starting characteristics is the prerequisite for avoiding the abnormal unstart state. To make the work close to the actual situation, an experimental study was performed on a scramjet model at a simulated freestream Mach number of 6.0 with pressure and thrust measurements. The inlet working status is determined by the heat release of the injected ethylene with reciprocating variations. The results show that the critical equivalence ratio of the restart state is lower than that of the unstart state, which means that the combustion weakens the inlet restart capability and raises the unstart/restart hysteresis phenomena. Specifically, two novel unstart/restart hysteresis phenomena are found: one may come from the dual-solution characteristics of the shock–combustion interaction and the other may come from the historical effect of reverse flow. Compared to the former type, the latter type requires greater downstream heat release and generates a larger hysteresis loop. In addition, the engine thrust characteristics of the whole unstart and restart processes are analyzed. The thrust increment in the shock–combustion interaction type exhibits nearly linearly. However, the thrust increment meets abrupt changes and strong oscillations in the reverse flow type, accompanied by the reverse flow's formation and disappearance, making the engine more difficult to restart.
Influence of the spacer filament on the flow and mass transfer in reverse osmosis seawater desalination membrane
Authors: Hu Xiao , Li Xinyu , Lin Peifeng , Zhu Zuchao , Lin Jianzhong
Published: August 2022

The influence of the spacer filament on the flow and mass transfer in reverse osmosis seawater desalination membrane is studied by the lattice Boltzmann method. The effects of Reynolds number (Re), blockage ratio (β), and osmotic pressure (ΔP) on the concentration polarization, permeate flux, the drag and lift forces on the spacer, and the shear stress on the membrane surface are studied, respectively. The results show that the spacer near the membrane surface at large Re can effectively prevent the formation of the concentration boundary layer. The vortices near the membrane surface bring the solutes into the bulk flow, then reducing the concentration polarization and improving the mass transfer efficiency. In addition, the changes of the flow pattern, the mean value of the drag coefficient (Cd), the lift coefficient (Cl), and the skin friction coefficient (fskin) are explored, respectively. The drag coefficient (Cd) increases with the increase in β and decreases with Re, the permeate flux across the membrane and the increasing of the osmotic pressure will slightly reduce the drag and lift coefficients.
Site fidelity and other attributes of infrequently trapped bats over two decades in a montane wet sclerophyll forest
Authors: Law B. , Brassil T. , Chidel M.
Published: August 2022

A long-term perspective on bat populations is lacking in most ecosystems. We describe fluctuations in capture rate, sex ratio, body condition, site fidelity and longevity of banded bats over two decades as part of an annual banding study in a montane forest. We focus on five species previously omitted from mark–recapture analyses because band returns were too low. Each species was infrequently trapped and/or retrapped, though this was often highly variable. A degree of site fidelity was recorded for all species, even those where trap success was low. We recorded maximum longevity (likely an underestimate) of at least 5 years for eastern falsistrelle Falsistrellus tasmaniensis and 7 years for Gould’s long-eared bat Nyctophilus gouldi and golden-tipped bat Phoniscus papuensis. Although N. gouldi was assumed to be highly detectable in harp traps, recaptures were few and none were retrapped more than once. No female greater-broad-nosed bat Scoteanax rueppellii were captured, a minor male bias was evident for F. tasmaniensis and sex ratios were close to parity for N. gouldi, P. papuensis and eastern horseshoe bat Rhinolophus megaphyllus. Body condition and mass were mostly stable over the study and were not related to periods of drought (except perhaps F. tasmaniensis in 2019) or higher rainfall. Although we recorded some degree of site fidelity among years, the extent of any seasonal or nomadic movements remains largely unknown.
Deformation responses of AZ31B magnesium alloy under combined shear-compression loading
Authors: Lin Hui , Lv Lin , Shao Lidong , Jin Tao
Published: August 2022

Combined shear-compression tests were conducted to AZ31B magnesium alloy through shear-compression specimen (SCS) and the deformation response process is captured by digital image correlation technology. The mechanical behaviours and deformation characteristics of SCS with different loading angles are analysed in detailed. Results show that the strain path of SCS is sensitive to the loading angle. The deformation behaviour at initial stage exhibits proportional loading and related to the tangent loading angle which reveals the designability of SCS for mechanical testing with specific requirements.
On a nonlinear model in domains with cavities arising from cardiac electrophysiology
Authors: Beretta Elena , Cerutti M Cristina , Pierotti Dario
Published: August 2022

In this paper we deal with the problem of determining perfectly insulating regions (cavities) from boundary measurements in a nonlinear elliptic equation arising from cardiac electrophysiology. With minimal regularity assumptions on the cavities, we first show well-posedness of the direct problem and then prove uniqueness for the inverse problem.
A comprehensive review of organic-inorganic composites based piezoelectric nanogenerators through material structure design
Authors: Lu Haowei , Zheng Haiwu
Published: August 2022

With the development and popularization of Internet of things, how to provide energy for distributed sensors, portable and embedded electronic devices have become a challenge. People’s requirements for power supply equipment are portable, sustainable and free maintenance. Therefore, organic–inorganic composites based on piezoelectric nanogenerator (PENG) is becoming one of promising solutions due to these advantages of low cost, excellent mechanical property and environmental adaptability, which can effectively harvest ubiquitous micro-nano mechanical high entropy energy and convert it into electricity to power electronics and nano-systems. In this study, the development of PENGs based on organic–inorganic composites have been reviewed and several strategies toward high output performance of PENGs, including various materials, piezoelectric fillers modification and structural design are summarized and discussed. The effects of different optimization methods on short circuit current (I
SC), open circuit voltage (V
OC) and output power of various PENGs as well as current difficulty for improving performance have been discussed. Meanwhile, some specific application scenarios in previous reports are also presented. Finally, we have proposed an outlook about future developments of flexible PENG and authors hope that this review can help researchers better understand this field and facilitate the improvement of flexible PENG to realize a broader application in self-powered system.
Effect of PbPc on electron structure and carrier dynamics of black phosphorus
Authors: Zhang Jianhua , Wang Shitan , Yang Baopeng , Niu Dongmei , Gao Yongli
Published: August 2022

Using lead phthalocyanine (PbPc) as surface doping material on black phosphorous (BP) we observe enhanced photo-excited carriers in the PbPc/BP heterostructure. The interfacial energy level alignment is investigated with ultra violet photoemission spectroscopy (UPS) and x-ray photoemission spectroscopy (XPS). The heterojunction is type I with gap of BP nested in that of PbPc, facilitating confinement of electrons and holes in BP. Ultrafast time-resolved two-photon photoemission (TR-2PPE) spectroscopy is used to study the influence of PbPc on the photo excited unoccupied electronic states and the dynamics of the relaxation processes. Monolayer PbPc can greatly increase the pump excited hot electrons and the 2 photon emission of BP. The enhanced population in the intermediate states is attributed to the straddling of the band alignment which benefits the photo excited electrons in PbPc transferring to BP. Density functional theory calculations supported the interface dipole and charge redistribution. Our results provide a fundamental understanding of the excellent opto-electrical response of PbPc/BP interface of promising application in the high efficient photo detectors.
Quantum quench of photoinduced semi-Dirac materials: Hall response
Authors: Aftab Tayyaba , Sabeeh Kashif
Published: August 2022

In this work, far from equilibrium Hall response of semi-Dirac materials is studied. This required preparing the system in non-equilibrium states through a quantum quench protocol. We show that in the non-equilibrium setting, there is non-zero Hall response even when instantaneous time reversal symmetry (TRS) is present and the Hall current persists for long times. This is in contrast to the equilibrium case where the system is required to break TRS for a Hall response. This highlights unique features of far from equilibrium response in semi-Dirac materials that are not present in the corresponding equilibrium state.
Quantum nonlocality and topological quantum phase transitions in the extended Ising chain
Authors: Dong Luzhao , Bao Jia , Guo Bin , Sun Zhaoyu
Published: August 2022

We use two-site quantum nonlocality to identify the topological quantum phase transitions (TQPTs) of the extended Ising model driven by varying system parameters. We investigate how the system parameters, including the anisotropies of the nearest-neighbor and the next-nearest-neighbor spin pairs, the transverse magnetic field, and the three-spin interaction, affect the quantum nonlocality. We show that the nonlocality cannot mark any TQPTs while its first derivative can perfectly characterize the TQPTs. By making the influences of the thermal fluctuations and the site distance of spin pairs on the critical behavior of the TQPTs analysis, we show that the sufficiently low temperature has a slight impact on the features of nonlocality and its first derivative while the site distance of spin pairs can significantly alter the properties of nonlocality and its first derivative. We further present the energy spectra and the trajectories of the winding vectors of the model to demonstrate that the quantum nonlocality can be employed to successfully signalize the TQPTs.
Deep neural networks based predictive-generative framework with data augmentation for designing composite materials
Authors: Ashank  , Chakravarty Soumen , Garg Pranshu , Kumar Ankit , Agnihotri Prabhat K , Agrawal Manish
Published: August 2022

Designing composite materials according to the need of applications is fundamentally a challenging and time-consuming task. A deep neural network-based computational framework is developed in this work to solve the forward (predictive) and the inverse (generative) composite design problem. The predictor model is based on the popular convolution neural network architecture and trained with the help of finite element simulations. Conventionally, a large amount of training data is required for accurate prediction from neural network models. A data augmentation strategy is proposed in this study which significantly saves computational resources in the training phase. It shown that the data augmentation approach is general and can be used in any setting involving periodic microstructures. We next use, the property predictor model as a feedback mechanism in the neural network-based generator model. The proposed predictive-generative model is used to obtain the composite microstructure for various requirements such as maximization of elastic properties, specified elastic constants, etc. The efficacy of the proposed predictive-generative model is demonstrated by solving certain class of problems. It is envisaged that the developed model coupled with data augmentation strategy will significantly reduce the cost and time associated with the composite material designing process for varying application requirements.
Selective area epitaxy of GaAs: the unintuitive role of feature size and pitch
Authors: Dede Didem , Glas Frank , Piazza Valerio , Morgan Nicholas , Friedl Martin , Güniat Lucas , Nur Dayi Elif , Balgarkashi Akshay , Dubrovskii Vladimir G , Fontcuberta i Morral Anna
Published: August 2022

Selective area epitaxy (SAE) provides the path for scalable fabrication of semiconductor nanostructures in a device-compatible configuration. In the current paradigm, SAE is understood as localized epitaxy, and is modelled by combining planar and self-assembled nanowire growth mechanisms. Here we use GaAs SAE as a model system to provide a different perspective. First, we provide evidence of the significant impact of the annealing stage in the calculation of the growth rates. Then, by elucidating the effect of geometrical constraints on the growth of the semiconductor crystal, we demonstrate the role of adatom desorption and resorption beyond the direct-impingement and diffusion-limited regime. Our theoretical model explains the effect of these constraints on the growth, and in particular why the SAE growth rate is highly sensitive to the pattern geometry. Finally, the disagreement of the model at the largest pitch points to non-negligible multiple adatom recycling between patterned features. Overall, our findings point out the importance of considering adatom diffusion, adsorption and desorption dynamics in designing the SAE pattern to create pre-determined nanoscale structures across a wafer. These results are fundamental for the SAE process to become viable in the semiconductor industry.
The art of building a smooth cosmic distance ladder in a perturbed universe
Authors: Umeh Obinna
Published: August 2022

How does a smooth cosmic distance ladder emerge from observations made from a single location in a lumpy Universe? Distances to the Type Ia supernova (SN1A) in the Hubble flow are anchored on local distance measurements to sources that are very nearby. We described how this configuration could be built in a perturbed universe where lumpiness is described as small perturbations on top of a flat Friedmann-Lemaıtre Robertson-Walker (FLRW) spacetime. We show that there is a non-negligible modification (about 11%) to the background FLRW area distance due to the presence of inhomogeneities in the immediate neighbourhood of an observer. We find that the modification is sourced by the electric part of the Weyl tensor indicating a tidal deformation of the local spacetime of the observer. We show in detail how it could impact the calibration of the SN1A absolute magnitude in the Hubble flow. We show that it could potentially resolve the SN1A absolute magnitude and Hubble tensions simultaneously without the need for early or late dark energy.
1 kHz, 12 MW, 300 ps microchip oscillator power amplifier system
Authors: Zhu Wentao , Yu Jun , He Huijun , Lin Qingdian , Guo Xiaoyang , Zhou Cangtao , Ruan Shuangchen
Published: August 2022

We report a diode-pumped passively Q-switched (PQS) sub-nanosecond master oscillator power amplifier system. The master oscillator is a PQS Nd:YAG/Cr:YAG monolithic microchip laser, yielding a pulse duration of ∼300 ps and pulse energy of 33 μJ at repetition frequency of 1 kHz. After passing two stages end pumped Nd:YVO4 amplifier, the pulse energy is boosted to 3.6 mJ and pulse peak power up to 12 MW with excellent stability (root mean square ∼ 0.14%) and high beam quality (M
2 < 1.22).
Design and Implementation of AGV Calling System Based on Android
Authors: Zhu Ouwen , Zhao Yuli
Published: August 2022

This paper designs and implements an AGV calling application based on Android. In the actual working environment, administrators need to call automatic guided vehicles to perform tasks and monitor them anytime and anywhere, so the AGV calling application based on Android came into being. Five business function modules of the system are realized: calling module, map monitoring module, task list module, node configuration module and communication configuration module. The application software is developed using Android Studio development tool, with the use of Vue framework and front-end HTML5+CSS+JavaScript technology to achieve interface rendering. TCP and HTTP protocols are used in the connection between the system and the central control system.
The Method for Automatic Adjustment of AGV’s PID Based on Deep Reinforcement Learning
Authors: Chen Yubin , Li Dancheng , Zhong Huagang , Zhao Ruihang
Published: August 2022

This paper proposes a method for automatic adjustment of PID(Proportion Integration Differentiation) based on deep reinforcement learning in order to solve the problem of smooth movement of AGV(Automated Guided Vehicle). First, based on reinforcement learning, the problem of AGV smooth operation is transformed into the solution of PID adjustment operation sequence. The action value model is constructed using the Deep Q-Learning Network(DQN) algorithm. Then, take the AGV adjustment PID as the research object. The goal is to achieve smooth movement of AGV. The specific design of AGV automatic PID adjustment method based on deep reinforcement learning is introduced. Finally, the simulation data is used to train the AGV action value network model. The method is validated in the ROS(Robot Operating System) simulation environment. Then compare with the actual environment. The results show that the automatic adjustment method of AGV’s PID based on deep reinforcement learning can adjust PID to the optimum without manual work. It can make AGV run smoothly. The feasibility and effectiveness of the method are illustrated and the problem of automatic PID determination in AGV movement control is solved.
Study of the IPOS DC/DC Converter for DC Offshore Wind Farm
Authors: Ding Huaxing , Zou Guibin , Ding Ning , Wang Chuanjie
Published: August 2022

With the development of the offshore wind farms, DC offshore wind farm topology is getting more attention due to its low loss and light weight, where the DC/DC converters with high voltage gain are key equipments. This paper studies the Input-Parallel-Output-Series(IPOS) converter based on Dual-Active-Bridge(DAB) topology, discusses the modulation and control method of the converter, and proposes a fault ride-through scheme. Simulation results validate the proposed topologies and control schemes.
Simulation Modeling of Switching over Current of Circuit Breaker in Intercity Train
Authors: Cao Weinan , Sun Ning , Wang Yong , Li Meng
Published: August 2022

The main interference source of axle counter is the over-current caused by the operation of circuit breaker by intercity train. This paper focuses on the simulation modeling technology of switching over-current of intercity train circuit breaker. Firstly, the mechanism of the interference when the circuit breaker is closed is studied by theoretical analysis; Then, the interference source model is established when the circuit breaker is closed, and the equivalent circuit model of interference path including vehicle body, vehicle body grounding system, traction network and high-voltage cable is obtained through calculation and analysis. The current of transformer primary grounding wire is measured on the actual vehicle, and the accuracy of the model is verified by comparing with the simulation model. Finally, the spectrum characteristics of the interference current in the rail are obtained by Fourier transform. In this paper, a simulation modeling method for analyzing the operating overcurrent of intercity vehicle circuit breaker is proposed, which can effectively evaluate the magnitude of the interference current generated by closing the circuit breaker into the rail, and provide a research basis for the follow-up study of the interference characteristics of the radiation field of rail current on the trackside axle counter.
Deep Supervised Cross-modal Hashing for Ship Image Retrieval
Authors: Guo Jiaen , Wang Haibin , Dan Bo , Lu Yu
Published: August 2022

The retrieval of multimodal ship images obtained by remote sensing satellites is an important content of remote sensing data analysis, which is of great significance to improve the ability of marine monitoring. In this paper, We propose a novel cross-modal ship image retrieval method, called Deep Supervised Cross-modal Hashing(DSCMH). It consists of a feature learning part and a hash learning part used for feature extraction and hash code generation separately, both two parts have modality-invariant constraints to keep the cross-modal invariability, and the label information is also brought to supervise the above process. Furthermore, we design a class attention module based on the cross-modal class center to strengthen class discrimination. The experiment results show that the proposed method can effectively improve the cross-modal retrieval accuracy of ship images and is better than several state-of-the-art methods.