bluuebunny/crossref_metadata_2025 huggingface dataset:
The reducibility and oxidation states of oxide-supported rhenium: experimental and theoretical investigations
Authors: Ting Kah Wei , Mine Shinya , Ait El Fakir Abdellah , Du Pengfei , Li Lingcong , Siddiki S. M. A. Hakim , Toyao Takashi , Shimizu Ken-ichi
Published: November 2022

The dependence of the Re L3- and L1-edge XANES spectra on the Re size was investigated, which revealed that the L3-edge was more sensitive than the L1-edge to the size of the Re clusters.
Fluorometric detection of a chemical warfare agent mimic (DCP) using a simple hydroxybenzothiazole–diaminomaleonitrile based chemodosimeter
Authors: Das Manas Kumar , Mishra Tanushree , Guria Subhajit , Das Debojyoti , Sadhukhan Juheli , Sarker Sushmita , Dutta Koushik , Adhikary Arghya , Chattopadhyay Dipankar , Adhikari Susanta Sekhar
Published: November 2022

Diethyl chlorophosphate (DCP) has a similar reactivity to sarin, which is widely known as a nerve agent that is often used in terrorist attacks.
Synthesis of a multi-functionalized NiCo2O4 spinel heterostructure via the hydrothermal route for high-performance photo-electrocatalytic, anti-bacterial and eco-toxicity applications
Authors: Sakthivel Chandrasekar , Nivetha Ambikapathi , Thiruppathi Govindhan , Sundararaj Palanisamy , Prabha Inbaraj
Published: November 2022

Simple, cost-effective, and abundant metal precursors are exhibited as multifunctional resources for improving structural changes and availability of rich Ni2+ and Co3+ spinels lead to superior performances for photo/electrocatalytic applications.
Ultrabroad spectral response and excellent SERS performance of PbS-assisted Au/PbS/Au nanostars
Authors: Feng Jing-Ru , Zhao Zhi-Rui , Xiong Zhong-Long , Kang Hao-Sen , Ding Si-Jing , Ma Liang , Zhou Li
Published: November 2022

We successfully prepared Au/PbS/Au nanostars with adjustable spine length. The SERS results show that the Au/PbS/Au nanostars (long) have the strongest Raman signal.
Playing catch and release with single molecules: mechanistic insights into plasmon-controlled nanogaps
Authors: Domke Katrin F. , Aragonès Albert C.
Published: November 2022

Here we present a mechanistic study of optically induced single-molecule capture and release processes in an interelectrode nanogap. Using unsupervised machine learning, the capture and release kinetics and free-energy profiles have been revealed.
Torsion effect of the imide ring on the performance of transparent polyimide films with methyl-substituted phenylenediamine
Authors: Lei Huanyu , Bao Feng , Peng Weifeng , Qiu Luhao , Zou Bingyu , Huang Mingjun
Published: November 2022

The torsion effects of imide rings play a critical role in the performance of aromatic CPI films.
Role of solution concentration in formation kinetics of bromide perovskite thin films during spin-coating monitored by optical in situ metrology
Authors: Rehermann C. , Schröder V. , Flatken M. , Ünlü F. , Shargaieva O. , Hoell A. , Merdasa A. , Mathies F. , Mathur S. , Unger E. L.
Published: November 2022

The solution chemistry of the precursor ink defines the formation kinetics of metal halide perovskites. Thus, rationalizing the formation process from solution via the deposition paves the way for high-quality thin films for optoelectronic devices.
Bromide ion promoted practical synthesis of phosphinothioates of sulfinic acid derivatives and H-phosphine oxides
Authors: Li Haoyuan , Yan Wenjie , Ren Peipei , Hu Huimin , Sun Runbo , Liu Meixia , Fu Zhengjiang , Guo Shengmei , Cai Hu
Published: November 2022

Herein, a method for the practical synthesis of thiophosphinates under metal free and open flask conditions is reported.
Metal-free visible-light-induced hydroxy-perfluoroalkylation of conjugated olefins using enamine catalyst
Authors: Tagami Koto , Ofuji Yu , Kanbara Tadashi , Yajima Tomoko
Published: November 2022

A sustainable, visible-light-induced hydroxy-perfluoroalkylation of electron-deficient olefins and styrenes catalyzed by ena mine were successfully developed.
Connecting the dots for fundamental understanding of structure–photophysics–property relationships of COFs, MOFs, and perovskites using a Multiparticle Holstein Formalism
Authors: Ghosh Raja , Paesani Francesco
Published: November 2022

The Multiparticle Holstein Formalism is a promising theoretical framework that efficiently bridges the gap between theory and experiments.
Robust singlet fission process in strong absorption π-expanded diketopyrrolopyrroles
Authors: Wang Long , Jiang Wenlin , Guo Shaoting , Wang Senhao , Zhang Mengfan , Liu Zuyuan , Wang Guoliang , Miao Yanqin , Yan Lingpeng , Shao Jiang-Yang , Zhong Yu-Wu , Liu Zitong , Zhang Deqing , Fu Hongbing , Yao Jiannian
Published: November 2022

Via π-expanded design strategy, a new robust SF system, Ex-DPP, has been successfully developed with high extinction coefficient, good molecular rigidity and excellent SF properties.
Energy harvesting of fully-flexible magnetoelectric composites using a piezoelectric P(VDF-TrFE) and magnetostrictive CoFe2O4 nanofiber
Authors: Nam Chaeyoung , Na Yujin , Park Sung Cheol , Kim Hyunseung , Jeong Chang Kyu , Hwang Geon-Tae , Park Kwi-Il
Published: November 2022

A fully-flexible magnetoelectric (ME) composite with 2-2 type structure is developed by adopting CoFe2O4 nanofiber-based magnetostrictive film and piezoelectric P(VDF-TrFE) and using simple electrospinning and spin-coating process.
Dynamic and mechanically robust and ultrafast healable ionogel for nerve fiber-inspired signal transmitter
Authors: Liu Ping , Pei Danfeng , Wu Yongpeng , Li Mingjie , Zhao Xihui , Li Chaoxu
Published: November 2022

A dynamic, robust, ultrafast healable and 3D shaped PUSeIL was synthesized and used as a self-weldable and recyclable conductor. When serving as the artificial nerve fiber, it could offer a communication unit for message and energy delivery.
Region-dependent volumetric oscillation of self-oscillating gels with gradient transducers
Authors: Lee Won Seok , Enomoto Takafumi , Akimoto Aya Mizutani , Yoshida Ryo
Published: November 2022

Gradient self-oscillating gels with a Ru(bpy)3 concentration gradient transducer exhibit autonomous, periodical and controlled region-dependent anisotropic volumetric oscillatory behavior (i.e., the amplitude) like the heart.
A thermo-responsive hydrogel loaded with an ionic liquid microemulsion for transdermal delivery of methotrexate
Authors: Shu Yang , Xue Rong , Gao Yiru , Zhang Wenxin , Wang Jianhua
Published: November 2022

A thermally responsive hydrogel loading ionic liquid microemulsion (IL-ME) facilitates transdermal delivery of methotrexate (MTX). The loading of the MTX-containing IL-ME on the Gel led to a significant increase in MTX permeation.
Ni2+-activated MgTi2O5 with broadband emission beyond 1200 nm for NIR-II light source applications
Authors: Tang Chuan-Jun , Liu Bo-Mei , Huang Lin , Wang Jing , Tang Qiang
Published: November 2022

An information restoration system, which can recover the secret information covered by ink with the aid of NIR-II spectroscopy technology.
Interaction between double nonspherical bubbles in compressible liquid under the coupling effect of ultrasound and electrostatic field
Authors: Deng Jin-Jie , Yu Ming , Yang Ri-Fu
Published: November 2022

A dynamic model for a double-bubble system in compressible liquid under the coupling effect of ultrasound and electrostatic field was developed here. In this study, we mainly discussed the effect of the interaction on the investigated bubble using the numerical solutions to the theoretic model. The variable parameters are the distance between bubble centers and the initial radius of the adjacent bubble. In addition, we applied approximate equations to analyse variations of the internal gas pressure and temperature of a bubble. We found that, the oscillation amplitude of a bubble with an adjacent bubble significantly reduces, compared to that of an isolated bubble.
Trajectory Tracking of COVID-19 Epidemic Risk Using Self-organizing Feature Map
Authors: Chen Ning , Chen An , Yao Xiaohui
Published: November 2022

The ongoing COVID-19 has become a worldwide pandemic with increasing confirmed cases and deaths across the globe. By July 2022, the number of cumulative confirmed cases reported to the World Health Organization (WHO) has risen to 550 million, with more than 6 million deaths in total. The analysis of its epidemic risk remains the focus of attention all over the world for a long time. The Self-organizing feature map (SOM), a vector quantization method, offers a data mapping approach to tracking the response of time series data on a well-trained map. This study aims at a trajectory tracking of COVID-19 epidemic risk in 237 countries measured by the number of new confirmed cases and deaths per day for over one year. A hybrid clustering method uses SOM and K-means to generate a risk map and then displays the trajectory of daily risk on the map. The experimental results demonstrate the promising functionality of SOM for trajectory tracking and give experts insights into the dynamic changes of COVID-19 risk.
The Relationship between Occupational Stress and Diet Quality with Productivity Loss in Islamic School Teachers in Medan: A Cross-sectional Study
Authors: Rosmiati Risti , Reswari Haryana Nila , Firmansyah Hardi , Purba Rasita , Rahman Nurfazriah Latifah , Edwin Fransiari Muhammad
Published: November 2022

Occupational stress and poor dietary practices have become a global health concern. Workers with poor dietary practices may be less productive and present at work. This study examined the relationship between occupational stress and diet quality on productivity loss among Islamic school teachers in Medan. This cross-sectional study was conducted on 50 Islamic school teachers in Medan. They were aged 19-64 years old and recruited using purposive sampling. Their occupational stress and diet quality were evaluated using the perceived stress scale (PSS) and the balanced diet index (BDI). Productivity loss was assessed based on the number of primary working days missed (absenteeism) due to poor health during six months. Negative binomial regression was used to examine the association between occupational stress and diet quality with productivity loss. The mean occupational stress, diet quality, and absenteeism were 44.89, 34.87, and 0.86 days, respectively. After controlling sociodemographic characteristics, the regression model indicated that productivity loss was positively associated with occupational stress (p=0.006). Consuming a high-quality diet was negatively associated with productivity loss (p=0.010). It concluded that occupational stress and diet quality were associated with teachers’ productivity loss. The study highlights the importance of occupational health promotion policies for teachers.
Beinschmerz – dermatologische Ursachen
Authors: Kahle Birgit
Published: November 2022

Einleitung Als Grund für akute oder chronische Beinschmerzen werden oft vaskuläre Erkrankungen vermutet. Es stellt sich die Frage, ob auch dermatologische Krankheiten mit Beinschmerzen einhergehen.

Methode Dermatologische Krankheitsbilder werden hinsichtlich einer begleitenden oder kausalen Schmerzhaftigkeit systematisch dargestellt.

Ergebnisse Bei Infektionserkrankungen der Haut steht der Schmerz im Vordergrund, allergische oder toxische Kontaktdermatitiden, Juckreizerkrankungen sowie kutane Autoimmunerkrankungen gehen mit Schmerzen einher.

Zusammenfassung Bei unklaren Beinschmerzen sollte auch an eine zugrundeliegende dermatologische Erkrankung gedacht werden. Der Schmerz kann als Prodromalsymptom bei Herpes zoster auftreten.
Der Geburtsbeginn in der Geburtsvorbereitung
Authors: König Christina
Published: November 2022

Viele Frauen erleben die Latenzphase als Beginn der Geburt, auch wenn dies laut
geburtshilflicher Definition noch nicht der Fall ist. Diese Differenz sowie das
– überwiegend systembedingte – Betreuungsdefizit in der
Latenzphase können das Geburtserlebnis der Frauen negativ beeinflussen.
Dieser Artikel zeigt, wie ein stärkerer Fokus der Geburtsvorbereitung
auf die Stärkung der Eigenkompetenz der Schwangeren das subjektive und
objektive geburtshilfliche Outcome verbessern und gleichzeitig den
Betreuungsaufwand in dieser Phase senken kann.
Betreuung von Schwangeren in der Latenzphase am Vinzenz Pallotti
Hospital in Bensberg
Authors: Campbell Katrina
Published: November 2022

Die Latenzphase der Geburt wird von Schwangeren sehr unterschiedlich
wahrgenommen. Obwohl es in dieser Phase noch nicht so richtig losgeht,
wünschen sich viele eine Betreuung im Krankenhaus. Dieses Beispiel aus
der Praxis zeigt, wie Hebammen gemeinsam mit den Frauen entscheiden, wie und wo
die Schwangeren die Latenzphase verbringen.
Übelkeit und Erbrechen in der Schwangerschaft – ein
Update zu Ursachen, Diagnostik und Therapie
Authors: Luhmann Linda
Published: November 2022

Ein Großteil aller Schwangeren leidet zu Beginn der Schwangerschaft an
Übelkeit und Erbrechen, manche von ihnen an einer besonders schweren
Form, der Hyperemesis gravidarum. Ursachen, Folgen und Therapieoptionen der
Erkrankung werden kontinuierlich erforscht. Ein neuer Definitionsansatz soll
nun für mehr Vergleichbarkeit der Studienergebnisse sorgen.
Incomplete resection of colorectal polyps of 4–20 mm in size when using a cold snare, and its associated factors
Authors: von Renteln Daniel , Djinbachian Roupen , Benard Florence , Barkun Alan N. , Bouin Mickael , Bouchard Simon , Deslandres Érik , Panzini Benoit , Sidani Sacha , Leduc Raymond , Jobse Bruce C. , Pohl Heiko
Published: November 2022

Background Cold snare polypectomy (CSP) is increasingly used for polypectomy and is recommended as the first-line modality for small (< 10 mm) polyps. This study aimed to evaluate incomplete resection rates (IRRs) when using CSP for colorectal polyps of 4–20 mm.

Methods Adults (45–80 years) undergoing screening, surveillance, or diagnostic colonoscopy and CSP by one of nine endoscopists were included. The primary outcome was the IRR for colorectal polyps of 4–20 mm, defined as the presence of polyp tissue in marginal biopsies after resection of serrated polyps or adenomas. Secondary outcomes included the IRR for serrated polyps, ease of resection, and complications.

Results 413 patients were included (mean age 63; 48 % women) and 182 polyps sized 4–20 mm were detected and removed by CSP. CSP required conversion to hot snare resection in < 1 % of polyps of < 10 mm and 44 % of polyps sized 10–20 mm. The IRRs for polyps < 10 mm and ≥ 10 mm were 18 % and 21 %. The IRR was higher for serrated polyps (26 %) compared with adenomas (16 %). The IRR was higher for flat (IIa) polyps (odds ratio [OR] 2.9, 95 %CI 1.1–7.4); and when resection was judged as difficult (OR 4.2, 95 %CI 1.5–12.1), piecemeal resection was performed (OR 6.6, 95 %CI 2.0–22.0), or visible residual polyp was present after the initial resection (OR 5.4, 95 %CI 2.0–14.9). Polyp location, use of a dedicated cold snare, and submucosal injection were not associated with incomplete resection. Intraprocedural bleeding requiring endoscopic intervention occurred in 4.7 %.

Conclusions CSP for polyps of 4–9 mm is safe and feasible; however, for lesions ≥ 10 mm, CSP failure occurs frequently, and the IRR remains high even after technical success. Incomplete resection was associated with flat polyps, visual residual polyp, piecemeal resection, and difficult polypectomies.
An Intelligent Medical Isolation Observation Management System Based on the Internet of Things
Authors: Sun Wensheng , Wang Chunmei , Sun Jimin , Miao Ziping , Ling Feng , Wu Guangsong
Published: November 2022

Background Since COVID-19 (coronavirus disease 2019) was discovered in December 2019, it has spread worldwide. Early isolation and medical observation management of cases and their close contacts are the key to controlling the spread of the epidemic. However, traditional medical observation requires medical staff to measure body temperature and other vital signs face to face and record them manually. There is a general shortage of human and personal protective equipment and a high risk of occupational exposure, which seriously threaten the safety of medical staff.

Methods We designed an intelligent crowd isolation medical observation management system framework based on the Internet of Things using wireless telemetry and big data cloud platform remote management technology. Through a smart wearable device with built-in sensors, vital sign data and geographical locations of medical observation subjects are collected and automatically uploaded to the big data monitoring platform on demand. According to the comprehensive analysis of the set threshold parameters, abnormal subjects are screened out, and activity tracking and health status monitoring for medical observation and management objectives are performed through monitoring and early warning management and post-event data traceability. In the trial of this system, the subjects wore the wristwatches designed in this study and real-time monitoring was conducted throughout the whole process. Additionally, for comparison, the traditional method was also used for these people. Medical staff came to measure their temperature twice a day. The subjects were 1,128 returned overseas Chinese from Europe.

Results Compared with the traditional vital sign detection method, the system designed in this study has the advantages of a fast response, low error, stability, and good endurance. It can monitor the temperature, pulse, blood pressure, and heart rate of the monitored subject in real time. The system designed in this study and the traditional vital sign detection method were both used to monitor 1,128 close contacts with COVID-19. There were six cases of abnormal body temperature that were missed by traditional manual temperature measurement in the morning and evening, and these six cases (0.53%) were sent to the hospital for further diagnosis. The abnormal body temperature of these six cases was not found in time when the medical staff came to check the temperature on a twice-a-day basis. The system designed in this study, however, can detect the abnormal body temperature of all these six people. The sensitivity and specificity of our system were both 100%.

Conclusion The system designed in this study can monitor the body temperature, blood oxygen, blood pressure, heart rate, and geographical location of the monitoring subject in real time. It can be extended to COVID-19 medical observation isolation points, shelter hospitals, infectious disease wards, and nursing homes.
Uterine Artery Embolization after Internal Iliac Artery Ligation
Authors: Al-Dhawi Abeer F. , Almetlag Mohammed H. , Almutairi Laila , Alobaidi Hatim , Garad Fares
Published: November 2022

Uterine artery embolization (UAE) is one of the primary therapies to treat symptomatic uterine fibroids. Even if the patient underwent internal iliac artery ligation during a massive pelvic hemorrhage or peripartum bleeding previously, UAE can be done through the collaterals for any other reasons. We report a 44-year-old woman who underwent UAE for symptomatic multiple uterine fibroids after internal iliac artery ligation with collaterals originating from the left external iliac artery. We briefly present the case's details and review collaterals pathways after left internal iliac artery ligation that might be encountered during UAE.
Photopyroelectric spectroscopy and calorimetry
Authors: Dadarlat D. , Tripon C. , White Iain R. , Korte Dorota
Published: November 2022

In this Tutorial, we present an overview of the development of the photopyroelectric (PPE) technique from its beginning in 1984 to the present day. The Tutorial is organized into five sections, which explore both theoretical and experimental aspects of PPE detection as well as some important spectroscopic and calorimetric applications. In the “Introduction” section, we present the fundamental basics of photothermal phenomena and the state-of-the-art of photopyroelectric technique. In the “Theoretical aspects” section, we describe some specific cases of experimental interest, with examples in both back and front detection configurations. Several mathematical expressions for the PPE signal in specific detection modes (combined back–front configurations and PPE–thermography methods) are also deduced. The “Instrumentation and experiment” section contains two subsections. The first describes several examples of setups used for both room temperature and temperature-controlled experiments. The second subsection is dedicated to the configuration of detection cells and to the various sensor/sample assemblies that are currently used in spectroscopic and calorimetric experiments for both liquid and solid samples. The “Applications” section is in fact a collection of experimental results dedicated to the thermal characterization of a wide range of solid and liquid samples. At the end of this section, we present some examples that have been selected to convey that the PPE technique is not only useful in the investigation of optical and thermal properties of a variety of condensed matter samples, but also to study physical and chemical processes such as molecular associations, food adulteration, or phase transitions. In “Concluding remarks,” we summarize the advantages of this technique in spectroscopic and calorimetric applications.
X-ray imaging and radiation transport effects on cylindrical implosions
Authors: Pérez-Callejo G. , Bailly-Grandvaux M. , Florido R. , Walsh C. A. , Gigosos M. A. , Beg F. N. , McGuffey C. , Mancini R. C. , Suzuki-Vidal F. , Vlachos C. , Bradford P. , Santos J. J.
Published: November 2022

Magnetization of inertial confinement implosions is a promising means of improving their performance, owing to the potential reduction of energy losses within the target and mitigation of hydrodynamic instabilities. In particular, cylindrical implosions are useful for studying the influence of a magnetic field, thanks to their axial symmetry. Here, we present experimental results from cylindrical implosions on the OMEGA-60 laser using a 40-beam, 14.5 kJ, 1.5 ns drive and an initial seed magnetic field of B0 = 30 T along the axes of the targets, compared with reference results without an imposed B-field. Implosions were characterized using time-resolved x-ray imaging from two orthogonal lines of sight. We found that the data agree well with magnetohydrodynamic simulations, once radiation transport within the imploding plasma is considered. We show that for a correct interpretation of the data in these types of experiments, explicit radiation transport must be taken into account.
Anomalous wavefront control via nonlinear acoustic metasurface through second-harmonic tailoring and demultiplexing
Authors: Lin Zhenkun , Zhang Yuning , Wang K. W. , Tol Serife
Published: November 2022

We propose a nonlinear acoustic metasurface concept by exploiting the nonlinearity of locally resonant unit cells formed by curved beams. The analytical model is established to explore the nonlinear phenomenon, specifically the second-harmonic generation (SHG) of the nonlinear unit cell, and validated through numerical and experimental studies. By tailoring the phase gradient of the unit cells, nonlinear acoustic metasurfaces are developed to demultiplex different frequency components and achieve anomalous wavefront control of SHG in the transmitted region. To this end, we numerically demonstrate wave steering, wave focusing, and self-bending propagation. Our results show that the proposed nonlinear metasurface provides an effective and efficient platform to achieve significant SHG and separate different harmonic components for wavefront control of individual harmonics. Overall, this study offers an outlook to harness nonlinear effects for acoustic wavefront tailoring and develops potential toward advanced technologies to manipulate acoustic waves.
Mg-implanted vertical GaN junction barrier Schottky rectifiers with low on resistance, low turn-on voltage, and nearly ideal nondestructive breakdown voltage
Authors: Matys Maciej , Kitagawa Kazuki , Narita Tetsuo , Uesugi Tsutomu , Suda Jun , Kachi Tetsu
Published: November 2022

Vertical GaN junction barrier Schottky (JBS) diodes with superior electrical characteristics and nondestructive breakdown were realized using selective-area p-type doping via Mg ion implantation and subsequent ultra-high-pressure annealing. Mg-ion implantation was performed into a 10 μm thick Si-doped GaN drift layer grown on a free-standing n-type GaN substrate. We fabricated the JBS diodes with different n-type GaN channel widths Ln = 1 and 1.5 μm. The JBS diodes, depending on Ln, exhibited on-resistance (RON) between 0.57 and 0.67 mΩ cm2, which is a record low value for vertical GaN Schottky barrier diodes (SBDs) and high breakdown (BV) between 660 and 675 V (84.4% of the ideal parallel plane BV). The obtained low RON of JBS diodes can be well explained in terms of the RON model, which includes n-type GaN channel resistance, spreading current effect, and substrate resistance. The reverse leakage current in JBS diodes was relatively low 103–104 times lower than in GaN SBDs. In addition, the JBS diode with lower Ln exhibited the leakage current significantly smaller (up to reverse bias 300 V) than in the JBS diode with large Ln, which was explained in terms of the reduced electric field near the Schottky interface. Furthermore, the JBS diodes showed a very high current density of 5.5 kA/cm2, a low turn-on voltage of 0.74 V, and no destruction against the rapid increase in the reverse current approximately by two orders of magnitude. This work demonstrated that GaN JBS diodes can be strong candidates for low loss power switching applications.
The measurement of photocathode transverse energy distribution curves (TEDCs) using the transverse energy spread spectrometer (TESS) experimental system
Authors: Jones L. B. , Juarez-Lopez D. P. , Scheibler H. E. , Terekhov A. S. , Militsyn B. L. , Welsch C. P. , Noakes T. C. Q.
Published: November 2022

The minimum achievable particle beam emittance in an electron accelerator depends strongly on the intrinsic emittance of the photocathode electron source. This is measurable as the mean longitudinal and transverse energy spreads in the photoemitted electron beam (MLE and MTE respectively); consequently, MLE and MTE are notable figures of merit for photocathodes used as electron sources in particle accelerators. The overall energy spread is defined by the sum of the MTE and the MLE, and the minimization of MTE is crucial to reduce emittance and thus generate a high-brightness electron beam. Reducing the electron beam emittance in an accelerator that drives a Free-Electron Laser (FEL) delivers a significant reduction in the saturation length for an x-ray FEL, thus reducing the machine’s construction footprint and operating costs while increasing the x-ray beam brightness. The ability to measure the transverse energy distribution curve of photoelectrons emitted from a photocathode is a key enabler in photocathode research and development that has prompted the Accelerator Science and Technology Centre (ASTeC) at the STFC Daresbury Laboratory to develop the Transverse Energy Spread Spectrometer to make these crucial measurements. We present details of the design for the upgraded TESS instrument with measured data for copper (100), (110), and (111) single-crystal photocathodes illuminated at UV wavelengths around 266 nm.
Comprehensive performance exploration of a novel pumped-hydro based compressed air energy storage system with high energy storage density
Authors: Yao Erren , Zhong Like , Zhang Yuan , Li Ruixiong , Wang Huanran , Xi Guang
Published: November 2022

A compressed air energy storage system is the key issue to facilitating the transformation of intermittent and fluctuant renewable energy sources into stable and high-quality power. The improvement of compression/expansion efficiency during operation processes is the first challenge faced by the compressed air energy storage system. Therefore, a novel pumped-hydro based compressed air energy storage system characterized by the advantages of high energy storage density and utilization efficiency is proposed in this study. To perform a comprehensive investigation on the system, the locations and magnitudes of irreversible sources within the system are estimated through the conventional exergy method, and the interactions among components and realistic potential for system performance improvement are identified by the advanced exergy method. The results indicate that the interactions among components are complex but not very significant since the endogenous exergy destruction is larger than the exogenous exergy destruction for all components within the system. Furthermore, the conventional exergy analysis reveals that the expander, compressor1, and pump are the most important components, accounting for 25.99%, 22.55%, and 15.34% of the total exergy destruction, respectively. Nevertheless, advanced exergy analysis recommends that the hydraulic turbine, pump, and expander have the optimization priorities since they share 28.61%, 27.72%, and 10.07% of the total endogenous avoidable exergy destruction. Finally, the overall system exergetic efficiency achieves a higher value of 18.49% under unavoidable conditions than that under real conditions.
TiO2 particle agglomeration impacts on radiative cooling films with a thickness of 50 μm
Authors: Wang Cun-Hai , Liu Ming-Xiang , Jiang Ze-Yi
Published: November 2022

The random micro-particle-embedded thin film is an inexpensive and scalable structure for radiative cooling (RC). However, current investigations on evaluating the performance of such films assume that the embedded particles are perfectly separated from each other. The particle agglomeration effects on the spectral characteristics of the film are dismissed. In this work, by comparing the spectral reflectivity and emissivity of a film composed of perfectly separated TiO2 particles, three-particle aggregations, five-particle aggregations, and ten-particle aggregations, we studied the particle agglomeration impacts on the performance of a disordered radiative cooling film with a thickness of 50 μm. The results show that the agglomeration suppresses the solar reflectivity of the particle-embedded film and harms the temperature drop and cooling power in RC applications. Therefore, particle agglomeration is intended to be industriously eliminated in the preparation of a random particle-embedded thin film for radiative cooling. The results in this paper provide a further explanation of the difference between the theoretical calculations and experimental measurements of the cooling performance of a particle-embedded RC film.
From lab to lamp: Understanding downconverter degradation in LED packages
Authors: Hariyani Shruti , Brgoch Jakoah , Garcia-Santamaria Florencio , Sista Srinivas P. , Murphy James E. , Setlur Anant A.
Published: November 2022

Downconverters, primarily inorganic phosphors, are critical components in white solid-state LED-based lighting and liquid crystal display backlights. Research efforts have led to a fundamental understanding of a downconverter's absorption, photoluminescence, and efficiency as a function of composition, structure, and processing conditions. However, considerably less work has focused on the reliability of phosphors once they are incorporated into LED packages. Solving these issues is often the final step before the commercialization of new materials, but the significant resources and time required to evaluate and mitigate materials failure are rarely discussed in the literature. In this Perspective, we discuss the need for conducting downconverter reliability testing and the potential of accelerating, screening, and understanding downconverter failure modes. Our focus highlights the mechanisms of failure and discusses how this influences materials selection and the design of different LED packages. We also stress the potential for accelerated reliability testing protocols and note the potential role first-principles calculations and data-driven models could play in establishing the compositional-processing trends for different aspects of downconverter reliability. We close with possible research directions that could improve downconverter reliability and emphasize the importance of assessing a material's (chemical) stability where multiple manufacturing and processing steps can dictate system performance.
Different roles of elongation and triangularity in the H-mode pedestal height enhancement through strong plasma shaping
Authors: Kim J. Y. , Han H. S. , Kim S. K.
Published: November 2022

While the peeling–ballooning mode is known to be stabilized by strong plasma shaping in a high-confinement mode (H-mode), a significant difference is found in the roles of elongation and triangularity. The elongation mainly stabilizes the high-n ballooning branch, while the triangularity of the low-n peeling one with some destabilization of the high-n ballooning one, where n is the toroidal mode number. This difference is conjectured mainly due to the magnetic shear effect which is substantially enhanced in a high triangularity regime, giving a destabilization on the ballooning branch, while a stabilization on the peeling one. An important consequence of these different roles of the two shape parameters is that they should work together to stabilize simultaneously both branches of the PBM, implying the necessity of synergy between them for the large pedestal height enhancement.
Low threshold amplified spontaneous emission and lasing from single crystals and polymer microspheres based on a blue aggregation-enhanced emission molecule
Authors: Li Yuanzhao , Han Pengbo , Zhang Xiaowei , Qiao Xianfeng , Yang Dezhi , Qin Anjun , Tang Ben Zhong , Peng Junbiao , Ma Dongge
Published: November 2022

Organic semiconductors as a gain medium have attracted much attention in organic lasers due to their unique properties, i.e., large stimulated emission cross section, widely tunable spectrum region, and mechanical flexibility. Aggregation-caused quenching broadly exists in amorphous solid films and single crystals, which result in high threshold. Here, we studied amplified spontaneous emission (ASE) and lasing properties of an aggregation-enhanced emission (AEE) molecule, namely, 2PB-AC, who owns high photoluminescence quantum efficiency in a solid film and a single crystal. The grown long rod-like single crystals exhibited very good ASE characteristics with a threshold of 48 μJ cm−2 and a full width at half-maximum (FWHM) of 8.4 nm. Furthermore, when forming polymer microspheres by a surface tension-induced self-assembly method, a low lasing threshold of 0.32 mJ cm−2 and a FWHM of 0.41 nm were also obtained well, and their lasing modes could be modulated by changing the diameter of the microspheres. The investigations on transient photoluminescence dynamics and femtosecond transient absorption analysis demonstrated that the high radiative decay rate and the well separation between a stimulated emission band and an excited state absorption band are the main reasons of good lasing performance, indicating that AEE molecules are promising lasing materials.
Joule heating induced non-melting phase transition and multi-level conductance in MoTe2 based phase change memory
Authors: Yang Zhe , Zhang Dayou , Cai Jingwei , Gong Chuantao , He Qiang , Xu Ming , Tong Hao , Miao Xiangshui
Published: November 2022

Phase change memory (PCM) is considered as a leading candidate for next generation data storage as well as emerging computing device, but the advancement has been hampered by high switching energy due to the melting process and amorphous relaxation induced large resistance drift. Polymorphic crystal-crystal transition without amorphization in metal dichalcogenides (TMDs) could be employed to solve these issues. Yet, the mechanism is still controversy. A melting-free PCM made of two dimensional (2D) MoTe2, which exhibits unipolar resistive switching (RS) and multi-level states with substantially reduced resistance drift via joule heating, is reported in this work. The device is first prepared based on the temperature dependence of Raman spectrum and electrical transport investigations on MoTe2 films. Significantly improved device performances on energy efficiency, switching speed, and memory window are further achieved by electrode size scaling down, indicating the key role of localized heating. Then, device scale transmission electron microscopy images reveal that the resistive switching stems from the transition between semiconducting 2H phase and metallic 1T′ phase. An entropy induced Te vacancies model is proposed to explain the reversible phase change mechanism in the MoTe2 based device. This study paves the way for further development of PCM based on atomically thin 2D TMDs, aiming for high density storage-class memory and high-precision neuromorphic computing.
Polyatomic time crystals of the brain neuron extracted microtubule are projected like a hologram meters away
Authors: Saxena Komal , Singh Pushpendra , Sarkar Jhimli , Sahoo Pathik , Ghosh Subrata , Krishnananda Soami Daya , Bandyopadhyay Anirban
Published: November 2022

When a perturbed periodic oscillation dephases, the system edits it to retrieve the original clock. The inherent clock born during retrieval is the time crystal. Time crystals have been explored for five decades, and only one inherent clock was detected in biological and artificial systems. Only one type of atom is used in those time crystals, but two or more atom types would lead to multi-functional and programmable time crystals. No such concept was ever conceived. Here, we demonstrate a multi-clock time crystal or a polyatomic time crystal in the brain neuron-extracted microtubule nanowire using dielectric resonance and quantum optics experiments. Earlier, one used to artificially reset the phase of an inherent clock to find a time crystal. Instead, we map how a biomaterial spontaneously generates distinct new clocks at many time domains at a time. We observe multiple time-symmetry-breaking events at a time. Moreover, unlike conventional time crystal research, we searched for polyatomic time crystals at least 103 orders lower than the excitation frequency region. Conventional time crystals could be rejected, arguing that inherent clocks born after the breaking of time symmetry are harmonics of the external input, and such an argument will not hold for us. Moreover, quantum experiments revealed a method to synthesize and fuse distinct clocks in one hologram as a polyatomic time crystal and project it like an antenna meters away. The discovery of material-like holographic engineering of polyatomic time crystals would make them useful.
Novel thin polymeric magnetic membranes study for applications in the future biomedical devices
Authors: Manzo Maurizio , Bakaraju Megha
Published: November 2022

Biomedical devices such as pumping/mixing fluids, cell-culturing, and drug delivery often use different actuation methods. Magnetic actuation using magnetic particles that are embedded in thin flexible polymeric sheets (membranes) is convenient to use, especially for medical implantable devices such as micropumps, due to the fact they do not require board batteries and exhibit better performances than other actuation methods. The fabrication process of these membranes uses a random distribution of particles. In this work, membranes with a local distribution of magnetic particles are investigated and compared to membranes with randomly distributed magnetic particles, which in turn may enhance the actuation performance for certain applications. Iron oxide particles are embedded into polydimethylsiloxane, and micromagnets are used to localize the position of the magnetic particles within the polymeric mixture during the fabrication process. Three different concentrations are investigated: low (7.5 w/v%), medium (10 w/v%), and high (12.5 w/v%). Static and dynamic measurements of membrane’s maximum deflection values are compared for both types of membranes with a random and a local distribution of magnetic particles. The maximum deflection location is shifted due to the presence of the localized magnetic field for a membrane with a local distribution of magnetic particles. From the experimental results, it is evident that the deflection performance result is much higher for the local distribution of the magnetic particles’ membrane during a static magnetic load and slightly lower during a dynamic (sinewave input) magnetic load at frequencies of 1 and 5 Hz.
Queering gender in Indonesian Instagram
Authors: Subekti Mega , Priyatna Aquarini , Adipurwawidjana Ari J.
Published: November 2022

The popularity of Mimi Peri as a queer micro-celebrity on Instagram shows a paradox in the Indonesian digital society, widely known for being very heteronormative towards gender and sexual identities. Despite the controversy over their queer performance and identity, Mimi Peri’s positive image as a “kind-hearted” and funny micro-celebrity managed to attract the attention of 1.9 million followers on Instagram. By using a virtual ethnographic paradigm within the framework of queer studies, this research examines how queer performativity in the @mimi.peri Instagram account during the periode between 2017 and 2018 presented and related to the Camp strategy. Switching their virtual identity, playing a role as a “female fairy”, parodying, and representing it as a comic figure have been identified as Mimi Peri’s practice and strategy to effectively gain the attention and acceptance of their followers. While there are established assumptions of queer subjects as fun and funny, we also argue that the strategy to commodify their comical performance can be seen as a form of negotiation to the predominant gender norms on Instagram.
Unimodular gravity vs general relativity: a status report
Authors: Carballo-Rubio Raúl , Garay Luis J , García-Moreno Gerardo
Published: November 2022

Unimodular gravity (UG) is an alternative to general relativity (GR) which, however, is so closely related to the latter that one can wonder to what extent they are different. The different behaviour of the cosmological constant in the semiclassical regimes of both frameworks suggests the possible existence of additional contrasting features. UG and GR are based on two different gauge symmetries: UG is based on transverse diffeomorphisms and Weyl rescalings (WTDiff transformations), whereas GR is based on the full group of diffeomorphisms. This difference is related to the existence of a fiduciary background structure, a fixed volume form, in UG theories. In this work we present an overview as complete as possible of situations and regimes in which one might suspect that some differences between these two theories might arise. This overview contains analyses in the classical, semiclassical, and quantum regimes. When a particular situation is well known we make just a brief description of its status. For situations less analysed in the literature we provide here more complete analyses. Whereas some of these analyses are sparse through the literature, many of them are new. Apart from the completely different treatment they provide for the cosmological constant problem, our results uncover no further differences between them. We conclude that, to the extent that the technical naturalness of the cosmological constant is regarded as a fundamental open issue in modern physics, UG is preferred over GR since the cosmological constant is technically natural in the former.
Stacking order effects on the electronic and optical properties of GaS/XMoY (X/Y = S, Se, Te) Van der Waals heterostructures: a first-principles study
Authors: Li Jialin , Li Mingming , Long Mengqiu , Fang Guozhao , Liu Min
Published: November 2022

Two-dimensional (2D) heterostructures formed by van der Waals (vdW) interactions have attracted considerable attention in the fields of electronics and optoelectronics. The stacking order is not only an important method for regulating interlayer interactions, but also an intrinsic property specific to 2D vdW heterostructures. Herein, the GaS/XMoY (X/Y = S, Se, Te) vdW heterostructures are proposed by first-principles calculations. The effects of stacking order (namely, GaS/SMoSe, GaS/SeMoS, GaS/SeMoTe and GaS/TeMoSe) on the electronic properties, light absorption, and photocatalysis of the heterostructures are discussed in detail. We identify stacking order as a dominant pathway for interlayer interactions, and surmise that stacking order effectively regulates dipole moment, mechanical flexibility, carrier mobility, optical absorption coefficient, and photocatalytic water-splitting of GaS/XMoY heterostructures. The in-plane biaxial strain can make the energy gap of each stacking order reach a maximum value, and their photocatalytic performance can also be improved to different degrees. This work analyzes the modulation effect of stacking order on the material properties of GaS/XMoY heterostructures, which provides theoretical clues for the design of efficient and stable optoelectronic devices and photocatalytic water-splitting.
Spatial light modulator-based maskless laser lithography using Fourier filtering and focal shift
Authors: Ulm Andreas , Ahmed Mirza Tareq , Schmitt Robert
Published: November 2022

We propose an optical setup based on a spatial light modulator (SLM) to facilitate rapid micro structuring such as laser lithography. The beam shaping of the system was addressed and we were able to minimize the effect of common issues of SLMs by adjusting our optical setup. We separated the zero-order focal plane from the first image plane via a focus shift to improve the image quality. This causes a Fourier filtering which is theoretically analyzed. This work explains challenges in filtering the zero-order beam and validates the achievable resolution of ∼11 μm of the proposed setup. The speed of maskless structuring can be improved by this approach while maintaining the resolution. We demonstrated the use of the setup for SLM-based maskless laser lithography.
Fabrication of nanostructure on Au nano-film by nanosecond laser coupled with cantilevered scanning near-field optical microscopy probe
Authors: Wang Xuewen , Cui Jianlei , Yin Hailong , Wang Zhijun , He Xiaoqiao , Mei Xuesong
Published: November 2022

Diffraction limit has been the constraint of the nanostructure fabrication. Because the scanning near-field optical microscopy (SNOM) can work in the evanescent near-field region, its application in nano-processing has received extensive attention from researchers globally. In this paper, we combined nanosecond laser with cantilevered SNOM probe. Utilizing the high precision of the confinement and enhancement effect of probe tip and the high instantaneous energy of the laser, we realized nanostructure fabrication and in situ detection on Au nano-film. Feature sizes down to 47 nm full width at half maximum were fabricated. We investigated the laser propagation through the SNOM tip aperture and the light field intensity distribution on the surface of substrate theoretically. The calculation results demonstrate that the laser is highly restricted within the SNOM aperture and enhanced on the exit plane at the rim of aperture. After the transmission, the light field intensity distribution on the surface of the Au nano-film was enhanced due to the localized surface plasmon resonance. The thermal distribution on the surface of Au nano-film indicates that the peak of the temperature distribution appeared at the surface right underneath the center of the aperture. It is proved that the simulation results are consistent with the experimental results.