bluuebunny/crossref_metadata_2025 huggingface dataset:
Updated characterization of long-period single companion by combining radial velocity, relative astrometry, and absolute astrometry
Authors: Philipot F. , Lagrange A.-M. , Rubini P. , Kiefer F. , Chomez A.
Published: January 2023

Context. Thanks to more than 20 yr of monitoring, the radial velocity (RV) method has detected long-period companions (P > 10 yr) around several dozens of stars. Yet, the true nature of these companions remains unclear because of the uncertainty as to the inclination of the companion orbital plane.

Aims. We wish to constrain the orbital inclination and the true mass of long-period single companions.

Methods. We used a Markov chain Monte Carlo (MCMC) fitting algorithm to combine RV measurements with absolute astrometry and, when available, relative astrometry data.

Results. We have lifted the sin(i) indetermination for seven long-period companions. We find true masses in the planetary mass range for the candidate planets detected in the following systems: Epsilon Indi A, HD 13931, HD 115954, and HD 222155. The mass of HD 219077 b is close to the deuterium-burning limit and its nature is uncertain because of the imprecise mass of the host star. Using additional RV measurements, we refine the orbital parameters of HIP 70849 b and find a mass in the planetary range. By combining RV data with absolute and relative astrometry, we significantly improve the characterization of HD 211847 B and properly determine its mass, which appears to be in the low-mass star range. This work illustrates how Gaia and HIPPARCOS allow for the orbital properties and masses of long-period RV companions to be further constrained.
General relativistic effects and the near-infrared and X-ray variability of Sgr A* I
Authors: von Fellenberg S. D. , Witzel G. , Bauböck M. , Chung H.-H. , Aimar N. , Bordoni M. , Drescher A. , Eisenhauer F. , Genzel R. , Gillessen S. , Marchili N. , Paumard T. , Perrin G. , Ott T. , Ribeiro D. C. , Ros E. , Vincent F. , Widmann F. , Willner S. P. , Anton Zensus J.
Published: January 2023

The near-infrared (NIR) and X-ray emission of Sagittarius A* shows occasional bright flares that are assumed to originate from the innermost region of the accretion flow. We identified 25 4.5 μm and 24 X-ray flares in archival data obtained with the Spitzer and Chandra observatories. With the help of general relativistic ray-tracing code, we modeled trajectories of “hot spots” and studied the light curves of the flares for signs of the effects of general relativity. Despite their apparent diversity in shape, all flares share a common, exponential impulse response, a characteristic shape that is the building block of the variability. This shape is symmetric, that is, the rise and fall times are the same. Furthermore, the impulse responses in the NIR and X-ray are identical within uncertainties, with an exponential time constant τ ∼ 15 m. The observed characteristic flare shape is inconsistent with hot-spot orbits viewed edge-on. Individually modeling the light curves of the flares, we derived constraints on the inclination of the orbital plane of the hot spots with respect to the observer (i ∼ 30° , < 75°) and on the characteristic timescale of the intrinsic variability (a few tens of minutes).
Microstructure, interfacial characteristics and wear properties of AZ31 surface selective laser cladding AlSi10Mg coatings
Authors: Li Yanling , Cai Zhihui , Ma Lifeng , Li Qihang , Zhao Zhanyong , Li Huodong
Published: January 2023

Aluminum-magnesium alloy dissimilar materials connected to make a composite structure, which can effectively make up for the shortcomings of magnesium alloy itself such as low hardness, and poor resistance to wear. The AlSi10Mg coating was successfully prepared on the surface of the AZ31 substrate by adding a transition zone using selective laser melting, which provides a new method for the composite of Mg-Al heterogeneous materials. The transition zone defects, coating microstructure, interfacial properties, and wear properties were studied. The results show that the formation of defects was mainly related to the unfused powder and oxide, and the transition layer thickness increases defects show a non-uniform increasing trend. Group A2 does not show defects and was the best parameter. It was well bonded with the substrate, and the hardness as a whole maintains a stable and high hardness value. Compared with the substrate, the wear resistance of the coating was improved, and its wear mechanism was mainly three-body wear, and the Si particles on the surface of the coating reduce the contact area of the friction pairs during sliding, which effectively improves the wear performance of the coating.
Study on the positive segregation in columnar-to-equiaxed transition zone
Authors: Wang Yadong , Zhang Lifeng
Published: January 2023

Laboratory experiments of steel ingots under three cooling modes and industrial trials of continuous casting (CC) blooms and billets were conducted, respectively. Corresponding results of the macrosegregation and the solidification structure were investigated. The mechanism of the positive segregation in the columnar-to-equiaxed transition (CET) zone was proposed. For laboratory experiments of ingots under three cooling modes, including water cooling, water cooling for 15 s followed by air cooling, and air cooling, obvious positive segregation was generated in the CET zone, and the degree of segregation was 1.024, 1.025, and 1.015, respectively. For industrial trials of three kinds of steel, CC bloom, round bloom, and billet, positive segregation was formed in the CET zone, and the degree of segregation was 1.06, 1.04, and 1.06, respectively. With the growth of columnar dendrites, solute elements were rejected on the liquid–solid interface. The downward flow near the columnar tip region and the upward flow in the center melt can carry the solute-rich melt to the molten pool. When the CET occurred, equiaxed grains accumulated around the columnar dendrite tips, and the solid network became less permeable. The liquid flow in the network was significantly suppressed, and thereby the solute-enriched liquid was ‘arrested’ locally. Solute-enrich liquid would be further sucked into the interdendritic region owing to the solidification shrinkage. As the sample was fully solidified, the obvious positive segregation was found at the CET zone.
Die Bedeutung des sozioökonomischen Status für das
Auftreten von psychischen Auffälligkeiten bei 11-bis 17-
jährigen Mädchen und Jungen in Deutschland. Ergebnisse der
KiGGS-Welle 2 (2014–2017)
Authors: Fendt Maren , Hölling Heike , Lampert Thomas , Waldhauer Julia
Published: January 2023

Ziel der Studie Ziel der Studie ist es, die Verteilungsunterschiede von
psychischen Auffälligkeiten (Emotionale Probleme,
Verhaltensauffälligkeiten, Probleme mit Gleichaltrigen,
Hyperaktivität) bei 11- bis 17-jährigen Mädchen und
Jungen zwischen sozioökonomischen Statusgruppen zu untersuchen.

MethodikDatenbasis bildete die Querschnittserhebung der „Studie
zur Gesundheit von Kindern und Jugendlichen in Deutschland“ –
KiGGS Welle 2 (2014–2017, n=15.023). Es wurden Daten von 11- bis
17-jährigen Jugendlichen (n=6599) insgesamt und getrennt nach
zwei Altersgruppen analysiert. Als abhängige Variable fungierten die
Elternangaben zum „Strengths and Difficulties Questionnaire“
(SDQ). Als unabhängige Variable diente ein mehrdimensionaler Indexwert,
der den sozioökonomischen Status (SES) der Familie
repräsentiert. Prävalenzen und auf binären logistischen
Regressionen basierende Odds Ratios (OR) werden ausgewiesen.

ErgebnisseEtwa 15,7% der 11- bis 17-Jährigen wiesen
psychische Auffälligkeiten auf. Mädchen zeigten häufiger
internalisierende und Jungen eher externalisierende Auffälligkeiten.
Psychische Auffälligkeiten waren bei Jugendlichen aus Familien mit
niedrigem SES im Vergleich zu denen mit hohem SES mehr als 2-fach erhöht
(aOR: 2,32; 95%-KI: 1,81–2,97; p<0,001). Mädchen
aus Familien mit niedrigem SES wiesen im Gegensatz zu Mädchen mit hohem
SES deutlich häufiger Auffälligkeiten in den Subdimensionen wie
„Emotionale Probleme“ auf (aOR: 2,06; 95%-KI:
1,49–2,98; p<0,001). Bei Jungen fanden sich geringfügige
Verteilungsunterschiede nach SES.

SchlussfolgerungPsychische Auffälligkeiten sind bei Jugendlichen
nach SES ungleich verteilt. 11-bis 17- jährige Jungen sind
unabhängig vom SES häufiger von psychischen
Auffälligkeiten betroffen, während bei Mädchen die
Verteilungsunterschiede nach SES stärker ausgeprägt sind.
AMIC am oberen Sprunggelenk
Authors: Hagenbrock Indra
Published: January 2023

Um Knorpeldefekte zu beheben, eignet sich die autologe matrixinduzierte Chondrogenese (kurz: AMIC®) in Kombination mit Chondro-Gide®, einer porzinen Kollagenmembran. Wie das Verfahren am oberen Sprunggelenk umgesetzt wird, lesen Sie im OP-Ablauf.
Wie lassen sich Wartezeiten für Patienten vor Operationen optimieren?
Authors: Son Stefanie , Morgenstern Ulrike
Published: January 2023

Wenn Patientinnen und Patienten vor einer Operation warten müssen, kann sie das so sehr belasten, dass die Ergebnisqualität des Behandlungsprozesses schlechter ausfällt. Positiv beeinflussen lässt sich das Warteerleben von Patienten maßgeblich durch eine gute Zusammenarbeit der verschiedenen Berufsgruppen. Wir stellen Ihnen die Optimierungspotenziale vor.
Ethische Fallmoderation
Authors: Stolecki Dietmar
Published: January 2023

Wenn zwischen dem Behandlungsteam, dem Patienten und den Angehörigen kein Konsens über die weitere Behandlung hergestellt werden kann, empfiehlt sich eine ethische Fallmoderation. Sie sorgt für Klarheit bezüglich der weiteren Versorgung und reduziert Konflikte im Team sowie zu den Angehörigen.
Longitudinal In Vivo Monitoring of Atheroprogression in Hypercholesterolemic Mice Using Photoacoustic Imaging
Authors: Ferraro Bartolo , Giustetto Pierangela , Schengel Olga , Weckbach Ludwig T. , Maegdefessel Lars , Soehnlein Oliver
Published: January 2023

Background and Aim The ability to recognize and monitor atherosclerotic lesion development using noninvasive imaging is crucial in preventive cardiology. The aim of the present study was to establish a protocol for longitudinal monitoring of plaque lipid, collagen, and macrophage burden as well as of endothelial permeability.

Methods and Results Photoacoustic signals derived from endogenous or exogenous dyes assessed in vivo, in plaques of albino Apoe
−/− mice, correlated with lesion characteristics obtained after histomorphometric and immunofluorescence analyses, thus supporting the validity of our protocol. Using models of atheroprogression and regression, we could apply our imaging protocol to the longitudinal observation of atherosclerotic lesion characteristics in mice.

Conclusions The present study shows an innovative approach to assess arterial inflammation in a non-invasive fashion, applicable to longitudinal analyses of changes of atherosclerotic lesion composition. Such approach could prove important in the preclinical testing of therapeutic interventions in mice carrying pre-established lesions.
The RhinoCEROS Guidelines: A Practical Tool for Reporting Nasal Anatomy on Computed Tomography Pertaining to Rhinoplasty
Authors: McIntosh Cameron , Stutterheim James , Prinsloo Hendrick , Randall Michael , Toman Julia , Pisapia Francesco
Published: January 2023

Cone-beam computed tomography (CT) is gaining popularity worldwide due to an increasingly diffuse and affordable in-office availability. It is becoming more commonplace for rhinoplasty surgeons to utilize this imaging as tool for preoperative assessment; however, there is inconsistency among radiologists commenting on specific structures of the nose or nasal cavity as there is currently no standardized reporting protocol. The goal of this article is to present clear guidelines for radiologists to report relevant nasal anatomy in the context of preoperative rhinoplasty evaluation. We have proposed the RhinoCEROS Guidelines, which stands for: Rhinoplasty Cephalometric Evaluation for Radiologic pre-Operative Systematization. This guideline highlights the primary aspects of nasal anatomy on CT that affect rhinoplasty outcomes and will provide radiologists with a straightforward template for reporting this increasingly popular use for CT scan.
Rare Diseases in Hospital Information Systems—An Interoperable Methodology for Distributed Data Quality Assessments
Authors: Tahar Kais , Martin Tamara , Mou Yongli , Verbuecheln Raphael , Graessner Holm , Krefting Dagmar
Published: January 2023

Background Multisite research networks such as the project “Collaboration on Rare Diseases” connect various hospitals to obtain sufficient data for clinical research. However, data quality (DQ) remains a challenge for the secondary use of data recorded in different health information systems. High levels of DQ as well as appropriate quality assessment methods are needed to support the reuse of such distributed data.

Objectives The aim of this work is the development of an interoperable methodology for assessing the quality of data recorded in heterogeneous sources to improve the quality of rare disease (RD) documentation and support clinical research.

Methods We first developed a conceptual framework for DQ assessment. Using this theoretical guidance, we implemented a software framework that provides appropriate tools for calculating DQ metrics and for generating local as well as cross-institutional reports. We further applied our methodology on synthetic data distributed across multiple hospitals using Personal Health Train. Finally, we used precision and recall as metrics to validate our implementation.

Results Four DQ dimensions were defined and represented as disjunct ontological categories. Based on these top dimensions, 9 DQ concepts, 10 DQ indicators, and 25 DQ parameters were developed and applied to different data sets. Randomly introduced DQ issues were all identified and reported automatically. The generated reports show the resulting DQ indicators and detected DQ issues.

Conclusion We have shown that our approach yields promising results, which can be used for local and cross-institutional DQ assessments. The developed frameworks provide useful methods for interoperable and privacy-preserving assessments of DQ that meet the specified requirements. This study has demonstrated that our methodology is capable of detecting DQ issues such as ambiguity or implausibility of coded diagnoses. It can be used for DQ benchmarking to improve the quality of RD documentation and to support clinical research on distributed data.
Consistency as a Data Quality Measure for German Corona Consensus Items Mapped from National Pandemic Cohort Network Data Collections
Authors: Yusuf Khalid O. , Miljukov Olga , Schoneberg Anne , Hanß Sabine , Wiesenfeldt Martin , Stecher Melanie , Mitrov Lazar , Hopff Sina Marie , Steinbrecher Sarah , Kurth Florian , Bahmer Thomas , Schreiber Stefan , Pape Daniel , Hofmann Anna-Lena , Kohls Mirjam , Störk Stefan , Stubbe Hans Christian , Tebbe Johannes J. , Hellmuth Johannes C. , Erber Johanna , Krist Lilian , Rieg Siegbert , Pilgram Lisa , Vehreschild Jörg J. , Reese Jens-Peter , Krefting Dagmar
Published: January 2023

Background As a national effort to better understand the current pandemic, three cohorts collect sociodemographic and clinical data from coronavirus disease 2019 (COVID-19) patients from different target populations within the German National Pandemic Cohort Network (NAPKON). Furthermore, the German Corona Consensus Dataset (GECCO) was introduced as a harmonized basic information model for COVID-19 patients in clinical routine. To compare the cohort data with other GECCO-based studies, data items are mapped to GECCO. As mapping from one information model to another is complex, an additional consistency evaluation of the mapped items is recommended to detect possible mapping issues or source data inconsistencies.

Objectives The goal of this work is to assure high consistency of research data mapped to the GECCO data model. In particular, it aims at identifying contradictions within interdependent GECCO data items of the German national COVID-19 cohorts to allow investigation of possible reasons for identified contradictions. We furthermore aim at enabling other researchers to easily perform data quality evaluation on GECCO-based datasets and adapt to similar data models.

Methods All suitable data items from each of the three NAPKON cohorts are mapped to the GECCO items. A consistency assessment tool (dqGecco) is implemented, following the design of an existing quality assessment framework, retaining their-defined consistency taxonomies, including logical and empirical contradictions. Results of the assessment are verified independently on the primary data source.

Results Our consistency assessment tool helped in correcting the mapping procedure and reveals remaining contradictory value combinations within COVID-19 symptoms, vital signs, and COVID-19 severity. Consistency rates differ between the different indicators and cohorts ranging from 95.84% up to 100%.

Conclusion An efficient and portable tool capable of discovering inconsistencies in the COVID-19 domain has been developed and applied to three different cohorts. As the GECCO dataset is employed in different platforms and studies, the tool can be directly applied there or adapted to similar information models.
Electrochemical Synthesis of trans-Olefins from Buta-1,3-dienes and Alkyl Halides
Authors: Yang Chao , Xia Wujiong , Zhang Haoxiang , Guo Lin
Published: January 2023

A facile electrochemical alkylation reaction of buta-1,3-diene derivatives with alkyl halides has been developed, generating highly selective trans-olefins as major products. This method exhibits significant advantages, including simple operation, mild conditions, and convenience of scale-up, and provides a novel route for the synthesis of trans-olefins.
Synthesis of Pyrrolizinone and Pyrrolizino[1,2-a]pyrrolizin-5-one Skeletons Starting From Pyrrole through a Single-Step and Catalyst-Free Approach
Authors: Menges Nurettin , Amudi Karina , Kuzu Burak , Kolak Seda , Genç Hasan
Published: January 2023

1H-Pyrrole reacted with lactone-type 2,3-furandione derivatives in anhydrous diethyl ether at room temperature to give a series of derivatives of pyrrolizinone (which is among the most important alkaloid skeletons) in a single step without a catalyst. Pyrrolizinone derivatives with a variety of substituents, such as phenyl, substituted phenyl, thienyl, trifluoromethyl, naphthyl, biphenylyl, ester, or oxalate, were obtained. The reaction of an equimolar amount of pyrrole gave pyrrolizinones, whereas an excess of pyrrole gave pyrrolizino[1,2-a]pyrrolizin-5-ones containing a skeleton that had not previously been reported. The purified molecules were obtained in yields of up to 91%. One cyclization process was carried out on a gram scale, yielding 0.952 g (71%) of the corresponding product.
The Heath of The Peri-Implant Phenotype after Immediate Insertion and Loading of One-Piece and Two-Piece Dental Implants in the Anterior Region. A Clinical and Cone-Beam Computed Tomographic Study
Authors: Assadawy Mohamed Ismail , Rifaie Ahamed Osama
Published: January 2023

Objective This study aimed to provide an inclusive comparison between the peri-implant phenotype of immediately placed in fresh extraction socket one-piece and two-piece implants with immediate loading in the anterior region.

Materials and Methods Twenty-two patients with a mean age of 36 ± 4.6 (4 males and 18 females)) were randomly allocated to the one-piece and the two-piece groups. Each patient had one immediate implant placement with immediate loading by provisional restorations. Gingival Index, Peri-implant Probing depth, Papilla Presence Index, and, Implant Quality Score were recorded at 3, 6, 9 months, and 18 months. Cone beam computerized tomography is utilized to assess peri-implant bone for 1 year.

Statistical analysis A two-sample t-test was used to compare the two groups.

Results Both groups showed similar clinical presentations. For group two, Gingival Index, Papilla Presence Index, Peri-implant Index, Implant Quality Score, and eri-implant bone level showed statistically significant improvement. Group one showed a non-significant increase in bone density.

Conclusions The peri-implant phenotype showed more predictable treatment outcomes in the context of health and esthetics in two-pieces than in one-piece.
Feedback lock-in: A versatile multi-terminal measurement system for electrical transport devices
Authors: Barnard Arthur W. , Mikheev Evgeny , Finney Joe , Hiller Han S. , Goldhaber-Gordon David
Published: January 2023

We present the design and implementation of a measurement system that enables parallel drive and detection of small currents and voltages at numerous electrical contacts to a multi-terminal electrical device. This system, which we term a feedback lock-in, combines digital control-loop feedback with software-defined lock-in measurements to dynamically source currents and measure small, pre-amplified potentials. The effective input impedance of each current/voltage probe can be set via software, permitting any given contact to behave as an open-circuit voltage lead or as a virtually grounded current source/sink. This enables programmatic switching of measurement configurations and permits measurement of currents at multiple drain contacts without the use of current preamplifiers. Our 32-channel implementation relies on commercially available digital input/output boards, home-built voltage preamplifiers, and custom open-source software. With our feedback lock-in, we demonstrate differential measurement sensitivity comparable to a widely used commercially available lock-in amplifier and perform efficient multi-terminal electrical transport measurements on twisted bilayer graphene and SrTiO3 quantum point contacts. The feedback lock-in also enables a new style of measurement using multiple current probes, which we demonstrate on a ballistic graphene device.
Realization of high-dynamic-range broadband magnetic-field sensing with ensemble nitrogen-vacancy centers in diamond
Authors: Wang Cao , Liu Qihui , Hu Yuqiang , Xie Fei , Krishna Krishangi , Wang Nan , Wang Lihao , Wang Yang , Toussaint Kimani C. , Cheng Jiangong , Chen Hao , Wu Zhenyu
Published: January 2023

We present a new magnetometry method integrating an ensemble of nitrogen-vacancy (NV) centers in a single-crystal diamond with an extended dynamic range for monitoring a fast changing magnetic-field. The NV-center spin resonance frequency is tracked using a closed-loop frequency locked technique with fast frequency hopping to achieve a 10 kHz measurement bandwidth, thus allowing for the detection of fast changing magnetic signals up to 0.723 T/s. This technique exhibits an extended dynamic range subjected to the working bandwidth of the microwave source. This extended dynamic range can reach up to 4.3 mT, which is 86 times broader than the intrinsic dynamic range. The essential components for NV spin control and signal processing, such as signal generation, microwave frequency control, data processing, and readout, are integrated in a board-level system. With this platform, we demonstrate a broadband magnetometry with an optimized sensitivity of 4.2 nT Hz−1/2. This magnetometry method has the potential to be implemented in a multichannel frequency locked vector magnetometer suitable for a wide range of practical applications, such as magnetocardiography and high-precision current sensors.
Transient liquid phase bonding technique for ultrahigh-vacuum compatible bimorph mirrors used in soft x-ray beamlines
Authors: Yuan Debo , Liu Zhengkun , Xiong Ying , Zhou Zhiyong , Zhang Guobin
Published: January 2023

Bimorph mirrors place stringent requirements on the welding technology of silicon substrates and piezoelectric ceramics to ensure their ultrahigh-vacuum compatibility. Conventional welding techniques usually require high temperature and pressure, which have a high impact on the welding substrate, while the use of organic adhesives for bonding does not guarantee their stability in ultrahigh vacuum. Here, the transient liquid phase bonding technology based on an Au–In metal system was studied to meet the requirement for ultrahigh-vacuum application. The microstructure, chemical composition, and related mechanical properties of the bonding at different welding conditions were investigated. Meanwhile, the piezo ceramics and the bond were baked at 150 °C to test the stability. The results show that a stable bonding was achieved between centimeter-scaled single crystal silicon and lead zirconate titanate ceramics at 200 °C temperature and 2.5 MPa pressure, and the piezo ceramics and the bond are not damaged by baking to 150 °C for 48 h.
Exploring wave–particle behaviors of entangled Bragg diffracted neutral atoms
Authors: Qureshi Izma , Abbas Tasawar , Imran Muhammad , Islam Rameez-ul
Published: January 2023

In this paper, we theoretically study the concept of the wave–particle duality of two entangled neutral Bragg diffracted atoms. This is an extension of a recent study where the same idea was proposed in the photonic setup [Man et al., Sci. Rep. 7, 42539 (2017)] using two independent Mach–Zehnder interferometers. Now, we propose a similar scheme using the cavity-QED based setup, which comprises two independent atomic de Broglie Mach–Zehnder–Bragg interferometers, a source cavity that generates two external momenta state entangled atoms. Once the atoms pass through the source cavity initially prepared in the superposition of zero and one photon, they emerge out of the cavity in entangled momenta state such that if one atom is transmitted to the upper interferometer, then the second atom must traverse the lower interferometer, and vice versa. The final atomic de Broglie beam splitter at the top interferometer is prepared in the superposition of zero and one photon and facilitates observing the wave or particle aspect in a single setting. This entire setup functions in off-resonant Bragg diffraction and the proposed schematics are shown to be experimentally feasible under contemporary research scenarios.
Combined binary and gasifier-based power generation from biomass and biowaste in Malaysia
Authors: Hossain Md. Zahir , Illias Hazlee Azil
Published: January 2023

Growing environmental concerns due to emission of greenhouse gas from the use of nonrenewable resources can be reduced with the aid of renewable resources, which are considered as an alternative fuel in the absence of fossil fuel in the future. Biomass, one of the renewable resources, is supposed to play an important role in energy sectors because it is the second cheapest energy source among the renewable resources. Apart from generating electricity by using the current biomass technology, such as combustion, gasification, or pyrolysis, a combination of binary and gasification can be one of the effective ways to harvest energy from biomass and to secure the energy production. In term of biomass, Malaysia is blessed with a plenty of renewable energy resources including solar, biomass, and hydro. Hence, a combined binary and biomass power generation can be a promising source of energy generation. In this work, a techno-economic feasibility study on a binary and gasifier-based power generation system from biomass and municipal waste is conducted. The study is conducted to determine the suitability of the system development in Malaysia based on the current resources available. From the results obtained, it is found that the estimated amount of electricity generated from palm empty fruit bunch and municipal waste is 369.65 GWh/yr and 21 262.327 84 GWh/yr, respectively, using combined binary and gasifier-based power generation. Thus, a combined binary and gasifier-based power generation from biomass and biowaste is feasible to be developed in Malaysia.
Nonstationary feature extraction based on stochastic resonance and its application in rolling bearing fault diagnosis under strong noise background
Authors: Wang Zhile , Yang Jianhua , Guo Yu , Gong Tao , Shan Zhen
Published: January 2023

When the load and speed of rotating machinery change, the vibration signal of rolling bearing presents an obvious nonstationary characteristic. Stochastic resonance (SR) mainly is convenient to analyze the stationary feature of vibration signals with high signal-to-noise ratio. However, it is difficult for SR to extract the nonstationary feature of rolling bearings under strong noise background. For one thing, the frequency change of nonstationary signals makes the occurrence of SR very difficult. For another, the features of rolling bearings are large parameters and further prevent the SR method from performing well. Therefore, combined with order analysis (OA), adaptive frequency-shift SR is presented in this paper. To solve the problem of frequency change, OA is used to convert the nonstationary feature into stationary feature, which resamples the nonstationary signal in the time domain to stationary signal in the angular domain. To solve the other problem, the frequency-shift method based on Fourier transform is adopted to move the fault feature frequency to low frequency, and thus SR is more likely to occur under small parameter conditions. The simulated and experimental results indicate that not only the amplitude of fault feature but also the signal-to-noise ratio is significantly improved. These demonstrate that the fault features of rolling bearing in variable speed conditions are extracted successfully.
Cinematic reflectometry using QIKR, the quite intense kinetics reflectometer
Authors: Ankner J. F. , Ashkar R. , Browning J. F. , Charlton T. R. , Doucet M. , Halbert C. E. , Islam F. , Karim A. , Kharlampieva E. , Kilbey S. M. , Lin J. Y. Y. , Phan M. D. , Smith G. S. , Sukhishvili S. A. , Thermer R. , Veith G. M. , Watkins E. B. , Wilson D.
Published: January 2023

The Quite Intense Kinetics Reflectometer (QIKR) will be a general-purpose, horizontal-sample-surface neutron reflectometer. Reflectometers measure the proportion of an incident probe beam reflected from a surface as a function of wavevector (momentum) transfer to infer the distribution and composition of matter near an interface. The unique scattering properties of neutrons make this technique especially useful in the study of soft matter, biomaterials, and materials used in energy storage. Exploiting the increased brilliance of the Spallation Neutron Source Second Target Station, QIKR will collect specular and off-specular reflectivity data faster than the best existing such machines. It will often be possible to collect complete specular reflectivity curves using a single instrument setting, enabling “cinematic” operation, wherein the user turns on the instrument and “films” the sample. Samples in time-dependent environments (e.g., temperature, electrochemical, or undergoing chemical alteration) will be observed in real time, in favorable cases with frame rates as fast as 1 Hz. Cinematic data acquisition promises to make time-dependent measurements routine, with time resolution specified during post-experiment data analysis. This capability will be deployed to observe such processes as in situ polymer diffusion, battery electrode charge–discharge cycles, hysteresis loops, and membrane protein insertion into lipid layers.
Abrasive slurry jet machining system using polyurethane@silica core–shell particles for internal surfaces of axisymmetric x-ray mirrors
Authors: Yokomae Shunya , Takeo Yoko , Shimamura Takenori , Senba Yasunori , Kishimoto Hikaru , Ohashi Haruhiko , Mimura Hidekazu
Published: January 2023

Abrasive machining has been used for inner surface processing of various hollow components. In this study, we applied an in-air fluid jet as a precision machining method for the inner surface of an axisymmetric x-ray mirror whose inner diameter was less than 10 mm. We employed an abrasive with a polyurethane@silica core–shell structure, which has a low density of about 1.2 g/cm3 and a relatively large particle size of about 15 µm. By using this abrasive, a practical removal rate and a smooth machined surface were simultaneously obtained. We performed figure corrections for an axisymmetric mirror and improved the circumferential figure accuracy to a sub-10 nm root mean square level. To evaluate the machining performance in the longitudinal direction of the ellipsoidal surface, we also performed periodic figure fabrication on the inner surface of a 114 mm-long nickel ellipsoidal mirror. X-ray ptychography, an optical phase retrieval method, was also employed as a three-dimensional figure measurement technique of the mirror. The wavefield of the x-ray beam focused by the processed ellipsoidal mirror was observed with the ptychographic system at SPring-8, a synchrotron radiation facility. The retrieval calculations for the wavefront error confirmed that a sinusoidal waveform with a period of 12 mm was fabricated on the mirror surface. These experimental results suggest that a nanoscale figure fabrication cycle for the inner surface consisting of jet machining and wavefront measurement has been successfully constructed. We expect this technique to be utilized in the fabrication of error-free optical mirrors and various parts having hollow shapes.
Three-degree-of-freedom autocollimation angle measurement method based on crosshair displacement and rotation
Authors: Guo Yan , Cheng Haobo , Liu Gang
Published: January 2023

The classic autocollimation method manages to measure the two-degree-of-freedom (2-DOF) angles, namely pitch and yaw, but fails to measure the roll angle. This paper proposes an autocollimation method that enables the simultaneous measurement of 3-DOF angles in which a carefully designed cooperated reflector (CR) splits the collimated beam into two returning beams parallel to the optical axis. The 3-DOF angles of the CR can be obtained by detecting the displacement and rotation of the crosshair images received by two photodetectors. The measurement principle is dissected, and the experimental results reveal that the constructed system achieves an accuracy of better than ±1.54 arcsec in the range of ±1000 arcsec. In addition, it is demonstrated that the system can be applied to the 3-DOF angle measurement of long-distance targets.
Spontaneous symmetry breaking and ghost states supported by the fractional PT-symmetric saturable nonlinear Schrödinger equation
Authors: Zhong Ming , Wang Li , Li Pengfei , Yan Zhenya
Published: January 2023

We report a novel spontaneous symmetry breaking phenomenon and ghost states existed in the framework of the fractional nonlinear Schrödinger equation with focusing saturable nonlinearity and PT-symmetric potential. The continuous asymmetric soliton branch bifurcates from the fundamental symmetric one as the power exceeds some critical value. Intriguingly, the symmetry of fundamental solitons is broken into two branches of asymmetry solitons (alias ghost states) with complex conjugate propagation constants, which is solely in fractional media. Besides, the dipole and tripole solitons (i.e., first and second excited states) are also studied numerically. Moreover, we analyze the influences of fractional Lévy index (α) and saturable nonlinear parameters (S) on the symmetry breaking of solitons in detail. The stability of fundamental symmetric soliton, asymmetric, dipole, and tripole solitons is explored via the linear stability analysis and direct propagations. Moreover, we explore the elastic/semi-elastic collision phenomena between symmetric and asymmetric solitons. Meanwhile, we find the stable excitations from the fractional diffraction with saturation nonlinearity to integer-order diffraction with Kerr nonlinearity via the adiabatic excitations of parameters. These results will provide some theoretical basis for the study of spontaneous symmetry breaking phenomena and related physical experiments in the fractional media with PT-symmetric potentials.
Phase detection of electron vortex beams on structured charge distribution
Authors: Wang Yan , Wang Xuan , Jia Chenglong
Published: January 2023

Recent advances in the production of so-called twisted electron (electron vortex) beams with sub-nanometer spot size offer unique opportunities to explore the role of orbital angular momentum (OAM) on electromagnetic microstructures. We address here the interaction between the OAM and an external electric field based on the Aharonov–Casher effect. Taking an inhomogeneous electric field generated by a point charge as an example, we show that the deformation of twisted electron's wavefront is very sensitive to the location and orientation of point charges and can be clearly visualized by interference patterns with a spherical wave. This phase shifting detection provides a high resolution representation for the structure and distribution of charged nanoparticles.
On the different regimes of positive DC corona discharges as a function of electrical and geometrical parameters
Authors: Yan Huijie , Benard Nicolas , Moreau Eric
Published: January 2023

This experimental study aims to better understand the electrical and optical properties of a positive DC corona discharge and to highlight the influence of applied voltage and electrode gap on the discharge regime. When the high voltage is increased, three successive regimes have been observed, including one that has never been reported in the literature to the best of our knowledge. This is certainly due to the fact that the tungsten needle used in these experiments is a commercial needle, with a tip of perfect surface finish. In fact, after the ignition voltage, the mean current slowly increases, and it perfectly follows the theoretical Townsend's law; this is the glow regime. When the voltage reaches a first threshold, a few small current pulses appear. However, this is not the breakdown streamer regime because photographs and intensified camera visualizations highlight that the propagation of streamers toward the grounded plate is limited to half of the gap. In this regime, the time-averaged current becomes higher than that of Townsend's law. Each current pulse is composed of only one bump, and the pulse frequency is higher (approximately 20 kHz) than that of the breakdown streamers. When the voltage reaches a second threshold, the magnitude of current pulses suddenly increases, but their frequency decreases (a few kHz); this is the transition toward the breakdown streamer regime. In this regime, each current pulse is composed of two bumps: the first one corresponds to the arrival of a primary streamer at the plate and the second one corresponds to a secondary streamer. Finally, we investigated the effects of the electrode gap. The magnitude and frequency of the current pulses increase when the gap decreases. Consequently, the offset between Townsend's curve and the experimental I–V characteristics increases when the gap decreases, because the pulse component of the total discharge current increases.
Machine learning empowered thin film acoustic wave sensing
Authors: Tan Kaitao , Ji Zhangbin , Zhou Jian , Deng Zijing , Zhang Songsong , Gu Yuandong , Guo Yihao , Zhuo Fengling , Duan Huigao , Fu YongQing
Published: January 2023

Thin film-based surface acoustic wave (SAW) technology has been extensively explored for physical, chemical, and biological sensors. However, these sensors often show inferior performance for a specific sensing in complex environments, as they are affected by multiple influencing parameters and their coupling interferences. To solve these critical issues, we propose a methodology to extract critical information from the scattering parameter and combine the machine learning method to achieve multi-parameter decoupling. We used the AlScN film-based SAW device as an example in which the highly c-axis orientated and low stress AlScN film was deposited on silicon substrate. The AlScN/Si SAW device showed a Bode quality factor value of 228 and an electromechanical coupling coefficient of ∼2.3%. Two sensing parameters (i.e., ultraviolet or UV and temperature) were chosen for demonstration, and the proposed machine learning method was used to distinguish their influences. Highly precision UV sensing and temperature sensing were independently achieved without their mutual interferences. This work provides an effective solution for decoupling of multi-parameter influences and achieving anti-interference effects in thin film-based SAW sensing.
Cavitation erosion risk assessment for a marine propeller behind a Ro–Ro container vessel
Authors: Melissaris Themistoklis , Schenke Sören , van Terwisga Tom J. C.
Published: January 2023

A novel cavitation erosion risk model, developed by Schenke et al. [“On the relevance of kinematics for cavitation implosion loads,” Phys. Fluids 31, 052102 (2019)], is applied to compute the cavitation implosion loads. The instantaneous energy balance during the collapse of cavitating structures is considered, where the initial potential energy is first converted into collapse-induced kinetic energy, before it is radiated to the surrounding surface at the final stage of the collapse. In this study, we focus on assessing the cavitation development and the risk of erosion on the blades of propellers operating behind a Ro–Ro container vessel. The presence of the hull contributes to the non-uniformity of the inflow. The consequent variation in velocities and angles of attack leads to the amplification of the cavitation dynamics, especially when the blade passes through the top position. Two designs are investigated that experience cavitation erosion on the pressure side. A statistical filter is used to attenuate low-amplitude implosion loads and identify the extreme events on the blade. The results show a very good correlation with the position of the actual erosion damage on the real propeller blades.
The influence of temperature on the electrical conductivity of GaN piezoelectric semiconductors
Authors: Qiao YanPeng , Zhao MingHao , Qin GuoShuai , Lu Chunsheng , Fan CuiYing
Published: January 2023

GaN is an excellent material choice for power devices due to its excellent properties such as super wide bandgap width and high electron mobility. However, the problem of temperature affects the thermo reliability and hinders the potential of GaN devices. In this paper, the electrical properties of GaN under temperature have been studied by the combination of numerical simulation and experimental research. The electric current change and electrical resistivity of polarized and depolarized GaN semiconductor samples were tested in an environment-test cabinet. Based on the influence of temperature, the expression of the resistivity curve vs temperature was established for polarized and depolarized GaN samples. It is shown that the resistivity model predictions are consistent with experimental results. The I–V characteristic curves under different temperatures were also measured. Thus, such a model is instructive to the reliable design of GaN high-temperature devices. The findings will be instructive to the optimal design of GaN electronic components.
Effective electronic band structure of monoclinic β−(AlxGa1−x)2O3 alloy semiconductor
Authors: Sharma Ankit , Singisetti Uttam
Published: January 2023

In this article, the electronic band structure of a β−(AlxGa1−x)2O3 alloy system is calculated, with β−Ga2O3 as the bulk crystal. The technique of band unfolding is implemented to obtain an effective band structure for aluminum fractions varying between 12.5% and 62.5% with respect to gallium atoms. A 160-atom supercell is used to model the disordered system that is generated using the technique of special quasi-random structures, which mimics the site correlation of a truly random alloy by reducing the number of candidate structures that arise due to the large number of permutations possible for alloy occupation sites. The impact of the disorder is then evaluated on the electron effective mass and bandgap, which is calculated under the generalized gradient approximation.
Evidence of defect-induced broadband light emission from 2D Ag–Bi double perovskites grown at liquid–liquid interfaces
Authors: Rury Aaron S. , Sanni Adedayo M. , Konadu Destiny , Danielson Tyler
Published: January 2023

Controlling the light emission spectra of low-dimensional hybrid organic–inorganic materials remains an important goal toward the implementation of these materials into real-world optoelectronic devices. In this study, we present evidence that the self-assembly of two-dimensional (2D) silver bismuth iodide double perovskite derivatives at the interface of aqueous and organic solutions leads to the formation of defects capable of modulating the light emission spectra of these materials. Through an analysis of the structural parameters used to explain the photoluminescence (PL) spectra of 2D perovskites, we show the light spectra emitted by (4-ammonium methyl)piperidinium (4-AMP) and (3-ammonium methyl)pyridinium (3-AMPy)-spaced AgBiI8 double perovskites formed through interfacial solution-phase chemistry differ qualitatively and quantitatively from thin film samples. We use previous results to propose the differences observed in the PL spectra of different material morphologies stem from equatorial iodide vacancy formation driven by the kinetics of self-assembly at the liquid–liquid interface. These results show the generality of these chemical physics principles in the formation of defect sites in solution-processed semiconducting nanomaterials, which could help enable their broad use in optoelectronic technologies.
Review of Scientific Instruments New Products
Authors: Mandelis Andreas
Published: January 2023

In order to supplement manufacturers’ information, this department will welcome the submission by our readers of brief communications reporting measurements on the physical properties of materials that supersede earlier data or suggest new research applications.
Hadamard states on spherically symmetric characteristic surfaces, the semi-classical Einstein equations and the Hawking effect
Authors: Janssen Daan W , Verch Rainer
Published: January 2023

We investigate quasi-free Hadamard states defined via characteristic initial data on null cones centred at the axis of symmetry in spherically symmetric space-times. We characterize the necessary singular behaviour of null boundary two-point functions such that one can define non-linear observables at this null boundary and give formulas for the calculation of these observables. These results extend earlier characterizations of null boundary states defining Hadamard states in the bulk of the null cone. As an application of our derived formulas, we consider their implications for the semi-classical Einstein equations and calculate the vacuum polarization associated with Hawking radiation near a collapsing body.
Probing system size dependence at high baryon density by systematic comparison of Ag+Ag and Au+Au reactions at 1.23A GeV
Authors: Reichert Tom , Kittiratpattana Apiwit , Li Pengcheng , Steinheimer Jan , Bleicher Marcus
Published: January 2023

We present UrQMD predictions for the comparison of the recently measured Ag+Ag and Au+Au runs at a beam energy of E
lab = 1.23A GeV explored by the HADES experiment. To this aim, different centrality definitions are investigated: We suggest that in the case of particle production, both systems should be compared at the same number of participating nucleons, while for a comparison of the (elliptic) flow, a selection on the initial state eccentricity—as in high energy reactions—is better suited. Generally, we find good agreement between both systems, if these centrality criteria are used. Specifically, the deuteron yields per participant and the pion to proton ratios are shown to scale with A
part except for very central Ag+Ag reactions due to stronger stopping in such reactions. The elliptic flow in both systems follows initial state eccentricity scaling, albeit with the opposite sign as compared to high energies, suggesting a strong relation between final flows and the initial state also at the low energies explored here. The observation of this scaling might then allow to obtain further information on the expansion properties (and the EoS) of matter at high baryon densities.