bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermal conductivity evaluation of ion irradiated Si3N4 and ZrN ceramics using spatial domain thermoreflectance
Authors: Terricabras Adrien J. , Ferrigno Joshua , Wang Ling , Khafizov Marat , Nelson Andrew T. , Zinkle Steven J.
Published: August 2022

Nitride ceramics have been investigated for different applications in the nuclear industry, such as space nuclear power, fusion reactor diagnostics and plasma heating, inert matrix fuels, and accident tolerant fuels. Although thermal conductivity remains one of the most important properties to track following irradiation, traditional techniques such as laser flash and xenon flash are limited to bulk sample characterization, which requires lengthy and cost-consuming neutron irradiation. This work used spatial domain thermoreflectance (SDTR) for the micrometer-scale measurement of thermal conductivity in 15 MeV Ni ion-irradiated silicon nitride and zirconium nitride from 1 to 50 dpa and 300 to 700 °C. The SDTR-measured unirradiated thermal conductivity was found to be consistent with the published data on bulk samples. Electrically conductive ZrN exhibits modest reduction after irradiation which is minimal at the highest irradiation temperatures. In electrically insulating Si3N4, the reduction is more significant and unlike ZrN, the reduction remains significant even at a higher irradiation temperature. The thermal resistance evolution following irradiation was compared with lattice swelling, which was determined using grazing incidence x-ray diffraction, and radiation-induced defects were observed using transmission electron microscopy. A saturation value was observed between 15 and 50 dpa for thermal conductivity degradation in both nitride ceramics and a direct correlation with high-temperature defect recombination was observed, as well as the potential presence of additional carrier scattering mechanisms.
High-yield magnetic recoil neutron spectrometer on the National Ignition Facility for operation up to 60 MJ
Authors: Gatu Johnson M. , Johnson T. M. , Lahmann B. J. , Séguin F. H. , Sperry B. , Bhandarkar N. , Bionta R. M. , Casco E. , Casey D. T. , Mackinnon A. J. , Masters N. , Moore A. , Nikroo A. , Hoppe M. , Mohammed R. , Sweet W. , Freeman C. , Picciotto V. , Roumell J. , Frenje J. A.
Published: August 2022

Recent progress at the National Ignition Facility (NIF), with neutron yields of order 1 × 1017, places new constraints on diagnostics used to characterize implosion performance. The Magnetic Recoil neutron Spectrometer (MRS), which is routinely used to measure yield, ion temperature (Tion), and down-scatter ratio (dsr), has been adapted to allow measurements of dsr up to 5 × 1017, and yield and Tion up to 2 × 1018 in the near term with new data processing techniques and conversion foil solutions. This paper presents a solution for extending MRS operation up to a yield of 2 × 1019 (60 MJ) by moving the spectrometer outside of the NIF shield wall. This will not only enhance the upper yield limit by 10× but also improve signal-to-background by 5×.
Eliminating white noise in spectra: A generalized maximum-entropy approach
Authors: Le L. V. , Kim Y. D. , Aspnes D. E.
Published: August 2022

In linear filtering, high-frequency (white) noise is reduced by apodization, which is the attenuation or elimination of high-order Fourier coefficients followed by an inverse transformation. Unfortunately, apodization requires compromises to be made among noise leakage, information loss, and Gibbs oscillations. These shortcomings are avoided with the corrected maximum-entropy (CME) procedure, but this procedure applies only to Lorentzian or approximately Lorentzian features. We develop a generalized maximum-entropy method based on partial Hilbert transforms that allows CME to be applied to any spectrum, thereby eliminating white-noise completely with no deleterious side effects. As Hilbert transforms are exact Kramers–Kronig replicas of the original endpoint-discontinuity-corrected segment, new spectral processing opportunities are also realized.
Neural network interaction potentials for para-hydrogen with flexible molecules
Authors: Durán Caballero Laura , Schran Christoph , Brieuc Fabien , Marx Dominik
Published: August 2022

The study of molecular impurities in para-hydrogen (pH2) clusters is key to push forward our understanding of intra- and intermolecular interactions, including their impact on the superfluid response of this bosonic quantum solvent. This includes tagging with only one or very few pH2, the microsolvation regime for intermediate particle numbers, and matrix isolation with many solvent molecules. However, the fundamental coupling between the bosonic pH2 environment and the (ro-)vibrational motion of molecular impurities remains poorly understood. Quantum simulations can, in principle, provide the necessary atomistic insight, but they require very accurate descriptions of the involved interactions. Here, we present a data-driven approach for the generation of impurity⋯pH2 interaction potentials based on machine learning techniques, which retain the full flexibility of the dopant species. We employ the well-established adiabatic hindered rotor (AHR) averaging technique to include the impact of the nuclear spin statistics on the symmetry-allowed rotational quantum numbers of pH2. Embedding this averaging procedure within the high-dimensional neural network potential (NNP) framework enables the generation of highly accurate AHR-averaged NNPs at coupled cluster accuracy, namely, explicitly correlated coupled cluster single, double, and scaled perturbative triples, CCSD(T*)-F12a/aVTZcp, in an automated manner. We apply this methodology to the water and protonated water molecules as representative cases for quasi-rigid and highly flexible molecules, respectively, and obtain AHR-averaged NNPs that reliably describe the corresponding H2O⋯pH2 and H3O+⋯pH2 interactions. Using path integral simulations, we show for the hydronium cation, H3O+, that umbrella-like tunneling inversion has a strong impact on the first and second pH2 microsolvation shells. The automated and data-driven nature of our protocol opens the door to the study of bosonic pH2 quantum solvation for a wide range of embedded impurities.
Enhancement of valley polarization in CVD grown monolayer MoS2 films
Authors: Chakrabarti Poulab , Mujeeb Faiha , Dhar Subhabrata
Published: August 2022

The development of future valley based electronics or valleytronics requires a high degree of valley polarization (VP) in large area monolayer (1L)-MoS2. Though it is possible to synthesize 1L-MoS2 films with large area coverage, VP property of as-grown films is found to be very poor. Here, we investigate the role of physisorbed air molecules and strain on the luminescence and the VP characteristics of large area monolayer MoS2 grown on various substrates by a microcavity based chemical vapor deposition (CVD) technique. The study shows that the removal of adsorbates from sulfur vacancy (VS) sites not only suppresses the broad sub-bandgap luminescence feature that typically dominates low temperature photoluminescence (PL) spectra of these films but also significantly enhances VP. Post-growth transfer of the 1L-MoS2 film from sapphire to a SiO2/Si substrate by a polystyrene assisted process is found to be highly effective in improving the polarization characteristic (∼80%) of K-valleys through relaxation of the biaxial tensile strain and the removal of physisorbed air molecules from the VS sites. The process is also found to provide long lasting protection for MoS2 films from air. The finding, thus, creates much needed opportunity to use CVD grown large area 1L-MoS2 for realization of valleytronics of the future.
Strain engineering of quantum confinement in WSe2 on nano-roughness glass substrates
Authors: de Brito Caique Serati , Rabahi Cesar Ricardo , Teodoro Marcio Daldin , Franco Douglas F. , Nalin Marcelo , Barcelos Ingrid D. , Gobato Yara Galvão
Published: August 2022

Strain engineering is a powerful tool for generating single-photon emitters in monolayer (ML) transition metal dichalcogenides. Here, we report on a simple method for generating sharp emission lines (linewidths ≈ 150–500 μeV) in a monolayer (ML) WSe2 on nano-roughness regions of Tb3+-borogermanate glasses. We performed a polarization-resolved magneto-luminescence study in WSe2/glass at low temperature. Remarkably, we observed several stable and linearly polarized doublet emission peaks in strained regions that are associated with a fine structure splitting due to the anisotropic electron–hole exchange interaction with g-factors of ∼8.4–9.8. Our results indicate that strain engineering on glass substrates is a promising tool for generating quantum dot-like emitters in ML WSe2 for possible integration with photonics systems for quantum information technology.
Comments on mechanisms for self-E → H and inverse H → E mode transitions in radio frequency inductively coupled plasmas
Authors: Zhao Y. , Ding Z. F.
Published: August 2022

The previously observed self-E → H and inverse H→E mode transitions were explained by unrelated mechanisms. The argument in this Brief Communication finds that both mode transitions can be interpreted via wall-heating that affects electron density by changing neutral density. In the self-E → H mode transition, the shift of the preset E-mode discharge to the E → H mode-transition point is caused by the increasing neutral density in the cooling down process of the chamber wall overheated in the preceding high-power H-mode discharge. The requirement for the inverse H →E mode transitions is a small-sized cylindrical radio frequency (RF) inductively coupled plasma source powered by multi-turn coil under which the strong wall-heating in the ramping-up phase of RF power or RF coil current leads to a reduction of neutral density in the subsequent ramping-down phase. The wall-heating can affect all processes in gas discharges but is most remarkable near a mode transition. The wall-heating effect on discharge mode transition has not been intensively investigated but was only suggested to explain the unknown mode transition in an electron cyclotron resonance plasma source [Jarnyk et al., Appl. Phys. Lett. 62, 2039 (1993)].
A hybrid prediction model for transitional separated flows over rough walls
Authors: Qiao Lei , Li Yi , Zhang Yang , Xu Jiakuan , Bai Junqiang
Published: August 2022

It is known that boundary layer transition and turbulent separation flow after transition can be influenced significantly by surface roughness. Because the traditional hybrid Reynolds-averaged-Navier–Stokes (RANS)/large eddy simulation method cannot predict the boundary layer transition, and the RANS-based transition model cannot accurately simulate the massively separated flow, the present study sought to build an effective modeling strategy for the laminar, roughness-induced-transition and attached turbulence/massively separated flows that couple the very-large-eddy-simulation model and a transition model considering roughness effects. This new hybrid model was examined in the cases of the separated flat plate and the rough cylinder. Our analysis shows that the new hybrid model operates in these transitional separated flows over smooth and rough walls. Compared with the results of other classical methods, the present results are more consistent with the measured data. Furthermore, the “drag crisis” phenomenon of the cylinder is accurately simulated by the present model.
Cryptochrome 1 as a state variable of the circadian clockwork of the suprachiasmatic nucleus: Evidence from translational switching
Authors: McManus David , Polidarova Lenka , Smyllie Nicola J. , Patton Andrew P. , Chesham Johanna E. , Maywood Elizabeth S. , Chin Jason W. , Hastings Michael H.
Published: August 2022

The suprachiasmatic nucleus (SCN) of the hypothalamus is the principal clock driving circadian rhythms of physiology and behavior that adapt mammals to environmental cycles. Disruption of SCN-dependent rhythms compromises health, and so understanding SCN time keeping will inform management of diseases associated with modern lifestyles. SCN time keeping is a self-sustaining transcriptional/translational delayed feedback loop (TTFL), whereby negative regulators inhibit their own transcription. Formally, the SCN clock is viewed as a limit-cycle oscillator, the simplest being a trajectory of successive phases that progresses through two-dimensional space defined by two state variables mapped along their respective axes. The TTFL motif is readily compatible with limit-cycle models, and in
Neurospora
and
Drosophila
the negative regulators Frequency (FRQ) and Period (Per) have been identified as state variables of their respective TTFLs. The identity of state variables of the SCN oscillator is, however, less clear. Experimental identification of state variables requires reversible and temporally specific control over their abundance. Translational switching (ts) provides this, the expression of a protein of interest relying on the provision of a noncanonical amino acid. We show that the negative regulator Cryptochrome 1 (CRY1) fulfills criteria defining a state variable: ts-CRY1 dose-dependently and reversibly suppresses the baseline, amplitude, and period of SCN rhythms, and its acute withdrawal releases the TTFL to oscillate from a defined phase. Its effect also depends on its temporal pattern of expression, although constitutive ts-CRY1 sustained (albeit less stable) oscillations. We conclude that CRY1 has properties of a state variable, but may operate among several state variables within a multidimensional limit cycle.
Comment on ‘Maxwell’s equations and Lorentz transformations’
Authors: Redžić D V
Published: August 2022

Aguirregabiria et al (2022 Eur. J. Phys. 43 035603) obtain the Lorentz transformations and the transformation equations for the electric and magnetic fields, and charge and current density, by restricting the principle of relativity to Maxwell’s equations in vacuum. We rectify and simplify their argument.
Electromicrofluidic device with integrated PDMS microchannel and laser-induced graphene electrodes for electrochemical detection of cardiac biomarker in a point-of-care platform
Authors: Dudala Sohan , Dubey Satish Kumar , Javed Arshad , Ganguly Anasuya , Goel Sanket
Published: August 2022

By providing a facile and scalable alternative to otherwise complex and resource-intensive synthesis of graphene, laser-induced graphene (LIG) is spearheading the translation of graphene-based propositions to deployable technologies for societal benefit. LIG is a versatile and economical synthesis approach which is being used on a variety of substrates and in a multitude of applications—including miniaturized sensing systems. One aspect that has not been addressed thoroughly in LIG-based miniaturized sensing systems is its successful integration with microfluidics and its possible use in point-of-care settings. To further diversify the applications of LIG with integrated microfluidics, this work reports on the development of an integrated flexible microfluidics-LIG based electrochemical biosensor. The work describes the methodology to develop a polydimethylsiloxane-LIG scribed polyamide microfluidic device in a leakage-free flexible application. In view of the excellent electrical and electrochemical properties of LIG, such device has been employed for electrochemical biosensing. The biosensing capabilities of the microfluidic device were validated via sensing of cardiac troponin I—a gold standard cardiac biomarker for early identification of acute myocardial infarction (AMI). The developed biosensor demonstrated a detection and quantification limit of 45.33 pg ml−1 and 151.10 pg ml−1 respectively, which are in clinically significant ranges for diagnosis of AMI. The µ-fluidic biosensor was also analyzed for stability and interference with other cardiac biomarkers. The developed integrated µ-fluidic electrochemical biosensor was evaluated for possible point-of-source applications in conjunction with a custom 3D printed peristaltic pump and smartphone-enabled miniaturized potentiostat.
Dislocations in 4H silicon carbide
Authors: Li Jiajun , Yang Guang , Liu Xiaoshuang , Luo Hao , Xu Lingbo , Zhang Yiqiang , Cui Can , Pi Xiaodong , Yang Deren , Wang Rong
Published: August 2022

Owing to the superior properties of the wide bandgap, high carrier mobility, high thermal conductivity and high stability, 4H silicon carbide (4H-SiC) holds great promise for applications in electrical vehicles, 5G communications, and new-energy systems. Although the industrialization of 150 mm 4H-SiC substrates and epitaxial layers has been successfully achieved, the existence of a high density of dislocations is one of the most severe bottlenecks for advancing the performance and reliability of 4H-SiC based high-power and high-frequency electronics. In this topical review, the classification and basic properties of dislocations in 4H-SiC are introduced. The generation, evolution, and annihilation of dislocations during the single-crystal growth of 4H-SiC boules, the processing of 4H-SiC wafers, as well as the homoepitaxy of 4H-SiC layers are systematically reviewed. The characterization and discrimination of dislocations in 4H-SiC are presented. The effect of dislocations on the electronic and optical properties of 4H-SiC wafers and epitaxial layers, as well as the role of dislocations on the performance and reliability of 4H-SiC based power devices are finally presented. This topical review provides insight into the fundamentals and evolution of dislocations in 4H-SiC, and is expected to provide inspiration for further control of dislocations in 4H-SiC.
Transparent and broadband switchable absorber/reflector based on structured water medium
Authors: Li Huangyan , Feng Youyi , Yuan Hang , Zhao Minxin , Wang Yi , Cao Qunsheng , Costa Filippo
Published: August 2022

A reconfigurable absorber/reflector, which has optical transparency and broadband switching function, is developed based on structured water medium. The conductive indium tin oxide coating is deposited on a thin polyethylene terephthalate film to act as the reflective backplane. Pure water is encapsulated by polydimethylsiloxane materials to construct structured water. The average optical transmittance is about 61.88%/56.44% in the visible spectrum of 380–760 nm with/without pure water. Based on the combination of the stacking technique and the super-element configuration, an obvious switching function from broadband absorption (12.47–28.43 GHz) to broadband reflection (12–30 GHz) can be attained under normal incidence through the injection and discharge of pure water. Besides, the broadband switchable characteristics of the proposed structure remain effective for transverse electric (TE) and transverse magnetic (TM) modes when illuminated by oblique incident waves up to 45°. Moreover, the proposed switchable absorber/reflector shows good temperature stability and can work under different liquid temperatures. Furthermore, the excellent performance of the proposed design is demonstrated by both simulated and experimental results, exhibiting great potential as transparent smart windows in large-scale ground-based stealth systems.
Single transition metal atom stabilized on double metal carbide MXenes for hydrogen evolution reaction: a density functional theory study
Authors: Jin Di , Hou Pengfei , Liu Xiaochun , Tian Yumiao , Xie Yu , Du Fei , Meng Xing
Published: August 2022

Double metal carbide MXenes have received considerable attention for use in renewable energy storage technologies in recent years. Here, density functional theory calculations were performed to investigate the hydrogen evolution reaction (HER) performances of double metal carbide MXenes (Cr2TiC2O2 and the Mo2TiC2O2 monolayer (ML) modified by a single transition metal (TM) atom (Co, Ni, Cu, Zn, Rh, Pd, Ag, Cd, Ir, Pt, Au, or Hg)). The thermodynamic stabilities of TM adatoms on pristine Cr2TiC2O2 and Mo2TiC2O2 MLs and defective Cr2TiC2O2 and Mo2TiC2O2 MLs with oxygen vacancies (denoted as TM-M′2TiC2O2−δ
, where M′ = Cr or Mo) were calculated, and the results indicated that the introduction of oxygen vacancies can increase the stabilities of TM adatoms. The TM modification on the MXenes surface tuned the Gibbs free energy of hydrogen adsorption

Δ

G
H, and the

Δ

G
H values of Au-, Co-Cr2TiC2O2−δ
, and Ni-Mo2TiC2O2−δ
closed to zero values (0.07, −0.07, and 0.02 eV, respectively). The presence of TM adatoms also changed the reaction mechanism of H2 desorption and reduced the activation barrier for H2 production to improve the catalytic efficiency. Nine TM-M′2TiC2O2−δ
systems were found to have both HER activity and a lower H2 desorption reaction barrier than the pristine MXenes. Systematic electronic structure analyses showed that charge rearrangement through TM modification could tune the number of electrons gained by the surface O atom and have an impact on the hydrogen adsorption strength. These results indicated that TM surface modification is an effective method for improving the HER catalytic activity of double TM carbides.
Carbon-based nanostructures as a versatile platform for tunable π-magnetism
Authors: de Oteyza Dimas G , Frederiksen Thomas
Published: August 2022

Emergence of π-magnetism in open-shell nanographenes has been theoretically predicted decades ago but their experimental characterization was elusive due to the strong chemical reactivity that makes their synthesis and stabilization difficult. In recent years, on-surface synthesis under vacuum conditions has provided unprecedented opportunities for atomically precise engineering of nanographenes, which in combination with scanning probe techniques have led to a substantial progress in our capabilities to realize localized electron spin states and to control electron spin interactions at the atomic scale. Here we review the essential concepts and the remarkable advances in the last few years, and outline the versatility of carbon-based π-magnetic materials as an interesting platform for applications in spintronics and quantum technologies.
Dipole-exchange spin waves in two-dimensional van der Waals ferromagnetic films and stripes
Authors: Hussain Bushra , Cottam Michael G
Published: August 2022

A spin-wave (SW) theory that includes the long-range dipole–dipole interactions is presented for monolayers of van der Waals (vdW) ferromagnets for which the magnetic ions lie on a two-dimensional honeycomb lattice. The dipolar interactions provide an additional anisotropy in these materials, along with the Ising exchange interaction and/or single-ion anisotropies that typically stabilize the two-dimensional magnetic ordering. Analytical results for the linearized SW energies are obtained for the ferromagnets in two geometries: complete films and finite-width stripes (or ribbons). In both cases it is found that the inclusion of the dipole–dipole interactions leads to a shift and sometimes a splitting of the magnetic modes in the vdW structure. Also, in the latter case, where the edges are assumed to be along the zigzag lattice directions, the dipole–dipole interactions are found to play a role, as well as the exchange interactions, in modifying the localized edge SWs. Numerical examples are given, including applications to the ferromagnet CrI3.
The young generation in radiation protection (IRPA YGN) in social media and online learning: ‘Brave New World’ or ‘Online Nightmare’?
Authors: Andresz Sylvain , Papp Cinthia , Clarijs Tom , Sakoda Akihiro , Sáez-Muñoz Marina , Qiu Rui
Published: August 2022

While online working seems to have become more common since the start of the Covid-19 pandemic, social media has the potential to offer greater interactivity and networking capacities. Thus it seems relevant for the IRPA Young Generation Network to investigate the use of social media by members of the young generation in radiation protection (RP) through an online survey. It was also the opportunity to collect early feedback about on-line learning. The survey received 89 answers from 15 countries. The most commonly used social media platforms were first Facebook, then LinkedIn and Twitter, but other social media were reported. The respondents have a multi-objectives approach while on social media, using it for different purposes (chiefly for sharing news and RP related information/educational material) and different audiences (e.g. public, professional). Yet, they are making a very moderate use based on the frequencies of publication and consultation and the challenges they see in social media. The survey also collected the view of the young generation about their practical experience in learning in a virtual setting and its advantages and disadvantages vs. in-person learning. Most participants expressed mixed-feelings about on-line learning. The results show that the young generation can play a role in supporting the extra- and intra-communication activities of the RP community.
Multi-channel data fusion and intelligent fault diagnosis based on deep learning
Authors: Guo Yiming , Hu Tao , Zhou Yifan , Zhao Kunkun , Zhang Zhisheng
Published: August 2022

In complex manufacturing systems, multi-channel sensor data are usually recorded for fault detection and diagnosis. Most existing multi-channel data processing methods adopt tensor analysis technology, which cannot effectively describe the temporal and spatial structures of the multi-channel data. The obstacles in multi-channel data analysis are the temporal correlation between the time-series data of the single-channel and the spatial correlation between different channels. In this paper, a novel deep convolutional neural network model is proposed for multi-channel data fusion and intelligent fault diagnosis. First, features of the multi-channel data are extracted from two scales. The extracted features are then fused through a multi-layer neural network. Finally, a classifier of fault modes is established by using the improved Softmax function. The fault diagnosis performance of the proposed model is evaluated and compared with other common methods in both the simulation studies and real-world case studies. Results show that the proposed methodology has superior fault diagnosis performance for multi-channel data.
Real-time observation of delayed excited-state dynamics in InGaN/GaN quantum-wells by femtosecond transient absorption spectroscopy
Authors: Udai Ankit , Ganguly Swaroop , Bhattacharya Pallab , Saha Dipankar
Published: August 2022

This work employs femtosecond transient absorption spectroscopy to investigate the ultrafast carrier dynamics of bound states in In0.14Ga0.86N/GaN quantum wells. The ground state (GS) dynamics usually dominate these characteristics, appearing as a prominent peak in the absorption spectra. It is observed that the excited state also contributes to the overall dynamics, with its signature showing up later. The contributions of both the ground and excited states in the absorption spectra and time-resolved dynamics are decoupled in this work. The carrier density in the GS first increases and then decays with time. The carriers populate the excited state only at a delayed time. The dynamics are studied considering the Quantum-Confined Stark Effect-induced wavelength shift in the absorption. The relevant microscopic optoelectronic processes are understood phenomenologically, and their time constants are extracted. An accurate study of these dynamics provides fundamentally essential insights into the time-resolved dynamics in quantum-confined heterostructures and can facilitate the development of efficient light sources using GaN heterostructures.
Interfacial engineering of 1D/2D heterostructured photoanode for efficient photoelectrochemical water splitting
Authors: Wang Ziyu , Qin Yimo , Wu Xin , He Kui , Li Xiaolong , Wang Juan
Published: August 2022

Solar-driven photoelectrochemical (PEC) water splitting for hydrogen generation is regarded as a sustainable strategy to relieve fossil resource issue. However, its PEC conversion efficiency still suffers from the low light absorption and high electron–hole recombination. Herein, we report 1D/2D hierarchical heterostructured photoelectrode constructed by ordered ZnO nanorod array and intimately attached ultra-thin Hematene (thickness of monolayer: 1–2 nm) for effective PEC water oxidation with visible light irradiation. The onset potential of Hematene/ZnO NRs photoanode (0.28 V versus RHE) for PEC water oxidation has an obvious negative shift compared with that of ZnO NRs (0.32 V versus RHE) indicating the enhanced PEC kinetics. Furthermore, reduced charge transport resistance (18.82 KΩ cm−2), a high carrier density of 9.03 × 1018 cm−3 and the resulting significantly enhanced incident photon-to-current efficiency enhancement compared with ZnO NRs photoanode were obtained for Hematene/ZnO NRs photoanode. All these were ascribed to the formation of large built-in electric field which was arising from the charge redistribution at the ZnO and Hematene interface, and the band alignment engineering between the components. In summary, such interfacial engineering may inspire the future development of 1D/2D hierarchical heterostructured photoanodes in the field of PEC water splitting.
Self-powered ultraviolet/visible photodetector based on graphene-oxide via triboelectric nanogenerators performing by finger tapping
Authors: Ejehi Faezeh , Shooshtari Leyla , Mohammadpour Raheleh , Asadian Elham , Sasanpour Pezhman
Published: August 2022

Self-sufficient power sources provide a promising application of abundant electronic devices utilized in detection of ambient properties. Recently, triboelectric nanogenerators (TENGs) have been widely investigated to broaden the self-powered systems by converting the ambient mechanical agitations into electrical voltage and current. Graphene oxide (GO), not only for sensing applications but also as a brilliant energy-related nanomaterial, provides a wide range of controllable bandgap energies, as well as facile synthesis route. In this study, GO-based self-powered photodetectors have been fabricated by conflating the photosensitivity and triboelectric characteristics of freestanding GO paper. In this regard, photodetection via TENGs has been investigated in two forms of active and passive circuits for ultraviolet (UV) and visible illumination. The photodetector responsivity upon UV enhanced from 0.011 mA W−1 for conventional GO-photoresistors up to 13.41 mA W−1 by active photodetection setup. Moreover, applying the active-TENG improved the efficiency from 0.25% (in passive TENG) to 4.21%. Our findings demonstrate that active TENGs might enable materials with insignificant optical response to represent considerably higher light-sensitivity by means of synergizing the effect of TENG output changes with opto-electronical properties of desired layers.
Relation between constituent material fraction in multifilamentary MgB2 wires and requirements for MRI magnets
Authors: Kodama Motomune , Kotaki Hiroshi , Suzuki Takaaki , Tanaka Hideki
Published: August 2022

Magnetic resonance imaging (MRI) occupies the largest segment of the commercial applications of superconductivity. The NbTi wire is typically applied to MRI magnets and fulfils their strict requirements. On the other hand, the dramatically large energy margin in the MgB2 wire is attractive for liquid helium-saving MRI magnets. However, there are many types of cross-sections in the MgB2 wires. This makes it difficult to analyse the applicability of the MgB2 wires to the MRI magnets systematically. This paper focuses on the in situ MgB2 wires with an iron matrix and a Monel reinforced member. Multiple evaluations are conducted for several types of MgB2 wires, and their applicability to the MRI magnets is discussed. Because the critical current density of the superconducting filaments does not largely depend on the cross-section of the wires, the engineering critical current density (J
e) is roughly proportional to the superconducting fraction (λ
sc). The acceptable bending strain of the heat-treated wires increases with the Monel fraction and is in the range of 0.3%–0.65%, which is larger than the value required for coil winding of the MRI magnets. Two types of protection approaches of the magnet are considered. One is an active protection. This approach requires a large fraction of the copper stabilizer in the cross-section of the wire and relatively reduces λ
sc and J
e. The other is the avoidance of quenches over the product lifetime using quick ramp-down of the magnet for unfortunate events, such as cooling system failure and emergency rundown. This approach requires no copper stabilizer and increases λ
sc and J
e thus widens the acceptable operational temperature range. The cross-section of the MgB2 wire can be designed with a certain level of freedom depending on its functional requirements.
Emergent dynamics of light-induced active colloids probed by XPCS
Authors: Zinn Thomas , Narayanan Theyencheri , Kottapalli Sai Nikhilesh , Sachs Johannes , Sottmann Thomas , Fischer Peer
Published: August 2022

Self-propelled particulate systems manifest certain collective behavior of living matter, which have been the subject of intense research over the past decades. One of the elegant methods for realizing such active motions is by means of custom synthesized Janus particles suspended in a catalytic medium that can be triggered upon illumination by ultraviolet light. In this work, the evolution of the particle dynamics from passive diffusive to active ballistic behavior upon light illumination was probed by multispeckle x-ray photon correlation spectroscopy (XPCS). This technique enables not only studying the emergence of active motions in three dimensions (3D) but also deciphering different contributions to the overall dynamics. Using a combination of homodyne and heterodyne analysis, the ensemble averaged mean velocity, velocity fluctuations and diffusion coefficient of particles were determined in the thermodynamic limit. Results revealed a gradual transition from diffusive to ballistic dynamics with systematic increase of the catalytic activity. At the intermediate region, the dynamics is dominated by Gaussian velocity fluctuations and an enhanced relaxation rate with a weaker wave vector dependence similar to superdiffusive behavior. For the highest activity, the dynamics became purely ballistic with Lorentzian-like distribution of velocity fluctuations. Presented results demonstrate that different aspects of active dynamics can be investigated in 3D over a broad range of Péclet numbers and other control parameters by means of multispeckle XPCS.
Unified approach to the nonlinear Rabi models
Authors: Duan Liwei
Published: August 2022

An analytical approach is proposed to study the two-photon, two-mode and intensity-dependent Rabi models. By virtue of the su(1, 1) Lie algebra, all of them can be unified to the same Hamiltonian with

Z

2

symmetry. There exist exact isolated solutions, which are located at the level crossings between different parities and correspond to eigenstates with finite dimension. Beyond the exact isolated solutions, the regular spectrum can be achieved by finding the roots of the G-function. The corresponding eigenstates are of infinite dimension. It is noteworthy that the expansion coefficients of the eigenstates present an exponential decay behavior. The decay rate decreases with increasing coupling strength. When the coupling strength tends to the spectral collapse point g → ω/2, the decay rate tends to zero which prevents the convergence of the wave functions. This work paves a way for the analysis of novel physics in nonlinear quantum optics.
Recompilation-enhanced simulation of electron–phonon dynamics on IBM quantum computers
Authors: Jaderberg Benjamin , Eisfeld Alexander , Jaksch Dieter , Mostame Sarah
Published: August 2022

Simulating quantum systems is believed to be one of the first applications for which quantum computers may demonstrate a useful advantage. For many problems in physics, we are interested in studying the evolution of the electron–phonon Hamiltonian, for which efficient digital quantum computing schemes exist. Yet to date, no accurate simulation of this system has been produced on real quantum hardware. In this work, we consider the absolute resource cost for gate-based quantum simulation of small electron–phonon systems as dictated by the number of Trotter steps and bosonic energy levels necessary for the convergence of dynamics. We then apply these findings to perform experiments on IBM quantum hardware for both weak and strong electron–phonon coupling. Despite significant device noise, through the use of approximate circuit recompilation we obtain electron–phonon dynamics on current quantum computers comparable to exact diagonalisation. Our results represent a significant step in utilising near term quantum computers for simulation of quantum dynamics and highlight the novelty of approximate circuit recompilation as a tool for reducing noise.
Introduction of unsaturated soil mechanics in Indonesia to improve the understanding on geotechnical engineering-related infrastructure problems
Authors: Krisnanto S , Susila E , Sahadewa A , Nawir H , Rismantojo E , Apriadi D
Published: August 2022

Several geotechnical engineering-related infrastructure problems cannot be quantified comprehensively using classical soil mechanics for saturated soils. This emphasizes the need of analysis using the framework of unsaturated soil mechanics (USM). The graduate course on soil mechanics for unsaturated soils is provided in Bandung Institute of Technology (ITB) to answer these challenges. The understanding on geotechnical engineering-related infrastructure problems in Indonesia is improved in the course. The understanding on the basic topics in USM is emphasized throughout the course. The balance between the eagerness for innovative design and the carefulness in the design is conveyed using the course. The laboratory testing apparatuses are being developed as a part of the course as well as a part towards the implementation of USM in Indonesia. An option of stages in introduction of USM in Indonesia is proposed.
Effects of Dammar as the partial substitution of bitumen in HMA AC-WC containing Buton Asphalt
Authors: Ngii E , One L , Nasrul N , Udo M I
Published: August 2022

Petroleum asphalt is the residue of fossil fuel distillation. The flexible pavement material generally uses petroleum asphalt. The world’s need for bitumen increases from year to year to pavement materials. Meanwhile, the availability of bitumen as a non-renewable resource is limited. To meet the world’s need for bitumen in the future, the utilization of natural polymers, such as a dammar, can be the best solution. This study aims to analyze the influence of dammar on the Marshall stability of HMA AC-WC containing Buton Granular Asphalt (BGA). This study was carried by using Marshall testing on the Asphalt Concrete Wearing Courses (AC-WC) containing Buton asphalt of 10%. Bitumen content is in all specimens amount 6,3%, bitumen content of BGA 50/30 is 22,48%, and the variation of dammar content is as the substitution of bitumen of 2.5-10%. Before mixing all material, it was first conducted the mixing of dammar and penetration at the temperature of 90°C to get a modified asphalt. The use of 10% dammar in asphalt mixtures meets the requirements of Bina Marga specifications. Utilization of Dammar content of 10% with BGA content of 10% can substitute petroleum asphalt by 45.68%.
Numerical modeling: the effect of land subsidence on hydrodynamic conditions and coastal morphology in Pekalongan
Authors: Muhammad I F , Yuanita N , Nugroho E O , Wijaya F S , Martin R J , Yola  , Fauzi N
Published: August 2022

This study examines the effect of land subsidence on hydrodynamic conditions and coastal morphology through numerical modeling using MIKE21 with 30-day simulation time. Land subsidence is assumed to be 10 cm/year, which affects bathymetry. There are 2 modeling scenarios, scenario 1 before (2016) and scenario 2 after land subsidence (2021). River discharge is assumed to be constant at 10 m3/s. The model calibration result on water level elevation and current velocity of the model simulation output and field data comparison based on the variation of Chezy Number, the smallest error was obtained at Chezy Number 50 m0.5/s. The sediment transport model sensitivity test was conducted on parameters of model type, sediment grain size, and river discharge. The result of sensitivity test demonstrated that the sediment grain size is the most sensitive parameter. By comparing the two model scenario results show that the current velocity in scenario 1 is greater than scenario 2 by 20%, significant wave height in scenario 1 is smaller than scenario 2 up to 0.1 m, and sedimentation in Mangrove Park increases up to ± 0.01m. Land subsidence reduces the current velocity, increases the significant wave height and sedimentation.
Sustainability Analysis of The Upper Citarum Watershed Based on Water quality, Water quantity, and Landuse Indicators
Authors: Marselina M , Putri N M
Published: August 2022

River is one of the surface water resources used to meet people’s need for daily clean water. Along with the population growth, problems related to waste produced are also increasing and causing environmental pollution, including river water pollution. River sustainability is one of the issues that has attracted the attention of various institutions, one of which is the Citarum River which is one of the sources of raw water for people in West Java. In this study, analysis of the sustainability condition from the upstream of the Citarum watershed was carried out in terms of three indicators, namely water quality, water quantity, and land use. The study was conducted using water quality data at four monitoring points, river water discharge, and land use maps around the upstream of the Citarum watershed. The three types of data were processed separately where water quality data were used to determine the status of water quality using the CCME WQI method, river water discharge data were used to calculate the River Regime Coefficient (RRC) value, and land use data were used to calculate the Land Cover Index (LCI). The index values obtained from each calculation were then analyzed and combined into one value for the Upper Citarum Sustainability Index (UCSI) using the composite index method. The results of this study found that the values of UCSI in the period of April – September 2014 are 0.442; 0.419; 0.415; and 0.403. All these values are categorized in the sub-sustainability class with the interpretation that some of the river functions are slightly damaged. The UCSI value also tends to decrease from time to time towards the un-sustainability class with water quality being the indicator that plays the most role in decreasing the UCSI value in this study.
Study of Temporal and Spatial changes in the Estuarine Area of the Mayangan River, West Java – Indonesia
Authors: Achiari Hendra , Rajin  , Gurusu
Published: August 2022

The estuarine of the Mayangan River is an area confluence the Mayangan River with the Java Sea. Pondok Bali beach which is about a half kilometer from River mouth of the Mayangan River has undergone a severe abrasion process since 2006. Pondok Bali’s coastline changes are expected to affect the estuary area. It caused flooding and changes in water quality on the Mayangan water river area. This research was studied the factors that cause of river level rise and changes in water quality of the Mayangan River whether it has an impact of coastline geometry change. The results of hydrodynamic and water quality model simulations showed river water discharge and increase Sea level is a more influential factor compared to the change in coastline geometry or bathymetry of the river mouth. The increase in salinity at some observation points of the Mayangan River from 2006 to 2014 was only 0.2 ppt, from 2011 to 2014 the salinity increase was only 0.1 ppt, and from 2014 to 2020 only 0.03 ppt.
Disaster and Resilient Infrastructures at Musi Riverside Settlement in Palembang
Authors: Wicaksono Bambang , Siswanto Ari , Fransiska Widya , Kusdiwanggo Susilo
Published: August 2022

The Settlement of the Musi Riverside in Palembang City is the strongest attraction for the community to build settlements. These settlement of the Musi Riverside, which have been inhabited for generations, has architectural and cultural aspects that reflect traditions that still survive. However, the community’s need for housing and riverside infrastructure that extends to cover river catchment areas actually causes changes in land topography, changes in water management, and even river widths that cause urban flooding. The purpose of this study is to reconstruct the resilience of residential infrastructure on the banks of the Musi River, Palembang in the face of urban flooding. This study uses a quantitative method with descriptive analysis, which is made in cross tabulation and based on a geographic information system (GIS). The results showed that the resilience of riverbank infrastructure in the settlements of 5 Ulu and 7 Ulu in dry land was in the form of road expansion, while in wetlands it was in the form of expansion of concrete roads. The direction in reconstructing the disaster resilience of riverside settlements based on exogenous and endogenous aspects is to plan infrastructure criteria for good riverside land.
The adaptor protein chaperone AAGAB stabilizes AP-4 complex subunits
Authors: Mattera Rafael , De Pace Raffaella , Bonifacino Juan S.
Published: August 2022

We show that the chaperone AAGAB binds the adaptor protein 4 (AP-4) ε and σ4 subunits, stabilizing them for assembly of the AP-4 complex. In the absence of AAGAB, AP-4 subunits are degraded by the proteasome, levels of the AP-4 complex are reduced, and the AP-4-cargo protein ATG9A accumulates at the TGN, all phenotypes resembling AP-4 deficiency.
Underprescribing of statin therapy in people with HIV at risk for atherosclerotic cardiovascular disease
Authors: Gallegos Aragon Kelsea , Ray Gretchen , Conklin Jessica , Stever Erin , Marquez Carlos , Magallanes Adan , Anderson Joe , Jakeman Bernadette
Published: August 2022

Purpose

People with HIV (PWH) are at increased risk for developing atherosclerotic cardiovascular disease (ASCVD). The primary objective of this study was to evaluate adherence to guideline recommendations on statin use in PWH for both primary and secondary ASCVD prevention in a single healthcare institution.

Methods

A retrospective chart review was performed to evaluate statin use for cardiovascular risk reduction in PWH 40 to 75 years of age at an HIV clinic over a 1-year evaluation period. The study included patients who met one of the 4 criteria for statin therapy defined in the “ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults.” Patient demographics were collected and a 10-year ASCVD risk score was calculated.

Results

A total of 432 PWH were evaluated for statin therapy; 205 patients (47.5%) met criteria for statin therapy. The majority of patients were male, the average age was 58 years, and the average time since HIV diagnosis was 19 years. The mean ASCVD risk score was 14.2%. Only 79 patients (38.5%) who met criteria were prescribed statin therapy, and only 45 (56.9%) were prescribed statin therapy of appropriate intensity. Use of ART pharmacokinetic enhancer was low and did not affect statin prescribing. Multivariable analysis found that age, diabetes, clinical ASCVD, and an appointment with a pharmacist clinician prescriber predicted statin utilization. A high ASCVD risk score (>20%) did not predict statin treatment.

Conclusion

Statin prescribing is low in PWH, who are at increased risk for ASCVD. Future research in PWH should focus on improving ASCVD risk assessment and exploring causes for statin underprescribing.