bluuebunny/crossref_metadata_2025 huggingface dataset:
Exoskeleton ageing and its relation to longevity and fecundity in female Australian leaf insects (
Authors: Bonduriansky Russell , Creak Caitlin
Published: May 2022

Senescence is a decline in reproduction and survival rate with advancing age resulting from deterioration of somatic tissues and systems throughout the body. Age-related somatic changes (somatic ageing) have been studied extensively in vertebrates but are less well known in other animals, including insects. Since adult insects have very limited ability to repair their exoskeleton, somatic ageing could involve deterioration and discolouration of the cuticle. We investigated age-related changes in wing pigmentation and abdominal cuticle necrosis in females of the Australian leaf insect Phyllium monteithi. Adult females varied markedly in the extent and pattern of pigmentation on their bodies, and we found that pigment spots on the forewings increased in size with age in most individuals. As females aged, most individuals also exhibited increasing levels of abdominal cuticle necrosis, resulting in the loss of abdominal cuticle along the margin of the abdomen. Neither the extent of pigmentation nor cuticle loss were clearly associated with reduced fecundity or longevity in the protected laboratory environment, but it remains unknown whether these age-related changes have functional implications in the wild. Our results show that the P. monteithi exoskeleton undergoes complex changes with age, with potential implications for functional traits and fitness.
Mast cell infiltration of the choroid and protease release are early events in age-related macular degeneration associated with genetic risk at both chromosomes 1q32 and 10q26
Authors: Mcharg Selina , Booth Laura , Perveen Rahat , Riba Garcia Isabel , Brace Nicole , Bayatti Nadhim , Sergouniotis Panagiotis I. , Phillips Alexander M. , Day Anthony J. , Black Graeme C. M. , Clark Simon J. , Dowsey Andrew W. , Unwin Richard D. , Bishop Paul N.
Published: May 2022

Significance

Genome-wide association studies have identified two major risk loci for age-related macular degeneration (AMD) on chromosome (Chr) 1 and Chr10. Here, we use proteomics to analyze submacular stromal tissue punches from older eye donors without AMD, comparing tissue from donors who were homozygous for high-risk alleles at Chr1 or Chr10 with tissue from donors with low risk at these two loci. A common change found in Chr1/Chr10–risk eyes was increased mast cell proteases, and immunohistochemistry confirmed the presence of increased mast cell numbers. This study, therefore, provides a unifying mechanistic link between Chr1 and Chr10 risk and suggests that mast cell infiltration of the choroid and degranulation are early events in AMD pathogenesis.
Pseudomonas aeruginosa
distinguishes surfaces by stiffness using retraction of type IV pili
Authors: Koch Matthias D. , Black Matthew E. , Han Endao , Shaevitz Joshua W. , Gitai Zemer
Published: May 2022

Significance

While many bacteria can sense the presence of a surface, the mechanical properties of different surfaces vary tremendously and can be as rigid as bone or as soft as mucus. We show that the pathogen
Pseudomonas aeruginosa
distinguishes surfaces by stiffness and transcriptionally tunes its virulence to surface rigidity. This connection between pathogenicity and mechanical properties of the infection site presents an interesting potential for clinical applications. The mechanism behind stiffness sensing relies on the retraction of external appendages called type IV pili that deform the surface. While this mechanism has interesting parallels to stiffness sensing in mammalian cells, our results suggest that stiffness sensing in much smaller bacterial cells relies on temporal sensing instead of spatial sensing strategies.
Observable characteristics of the charged black hole surrounded by thin disk accretion in Rastall gravity
Authors: Guo Sen , Li Guan-Ru , Liang En-Wei
Published: May 2022

The observable characteristics of the charged black hole (BH) surrounded by a thin disk accretion are investigated in the Rastall gravity. We found that the radii of the direct emission, lensing ring, and photon ring dramatically increased as the radiation field parameter increased, but they only weakly depend on the BH charge. Three positions of the radiation accretion disk relative to the BH are considered, i.e. the innermost accretion disk is closed to the radii of the innermost stable circular orbit, the photon ring of the BH, and the event horizon of the BH. The observed images in three cases respectively are obtained. It is found that the total observed flux is dominated by the direct emission, the lensing ring provides a small contribution, and the photon ring is negligible. The lensing and photon rings could not be observed in the blurred image with the EHT resolution. Our results suggest that the observable characteristics of the charged BH surrounded by the thin disk accretion in the Rastall gravity depend on both the BH space-time structure and the position of the radiating accretion disk with respect to the BH. The research of these BH images may serve as a probe for the BH-disk structure in M87* like nearby active galactic nuclei.
Broadband and high-efficient reflective linear-to-circular polarizer with Wi-Fi shaped metasurface
Authors: Tian Feng , Wang Yuxiang , He Jiahao , Hao Han , Ma Xia , Huang Xiaojun
Published: May 2022

Arbitrarily manipulating the polarization states of electromagnetic waves has gained interest due to its wide application in modern wireless communication systems. However, conventional polarizers face major bottlenecks such as bulky size, low efficiency and narrow frequency band. This paper proposes a reflective linear-to-circular polarizer using Wi-Fi shaped metasurface, and the designed polarizer can efficiently convert the linearly polarized incident waves into nearly perfect circularly polarized reflected waves in wideband frequency region of 12.1–20 GHz. Based on simulations, the polarizer has an axial ratio of ⩽3 dB at 12.1–20 GHz and a relative bandwidth of 49.2%. The polarization conversion rate is over 97% in 12.1–20 GHz. The physical analysis of the polarization conversion is based on the surface current distributions. To validate the simulations, microwave tests are carried out, and the theory, simulations, and experiments all accord quite well.
Strain assisted magnetoelectric coupling in ordered nanomagnets of CoFe2O4/SrRuO3/(Pb(Mg1/3Nb2/3)O3–PbTiO3) heterostructures
Authors: Ahlawat Anju , Khan Azam Ali , Deshmukh Pratik , Bhartiya Sushmita , Satapathy S , Shirolkar Mandar M , Wang Haiqian , Choudhary R J
Published: May 2022

We have explored the electric field controlled magnetization in the nanodot CoFe2O4/SrRuO3/PMN-PT (CFO/SRO/PMN-PT) heterostructures. Ordered ferromagnetic CFO nanodots (∼300 nm lateral dimension) are developed on the PMN-PT substrate (ferroelectric as well as piezoelectric) using a nanostencil-mask pattering method during pulsed laser deposition. The nanostructures reveal electric field induced magnetization reversal in the single domain CFO nanodots through transfer of piezostrains from the piezoelectric PMN-PT substrate to the CFO. Further, electric field modulated spin structure of CFO nanomagnets is analyzed by using x-ray magnetic circular dichroism (XMCD). The XMCD analysis reveals cations (Fe3+/Co2+) redistribution on the octahedral and tetrahedral site in the electric field poled CFO nanodots, establishing the strain induced magneto-electric coupling effects. The CFO/SRO/PMN-PT nanodots structure demonstrate multilevel switching of ME coupling coefficient (α) by applying selective positive and negative electric fields in a non-volatile manner. The retention of two stable states of α is illustrated for ∼106 seconds, which can be employed to store the digital data in non-volatile memory devices. Thus the voltage controlled magnetization in the nanodot structures leads a path towards the invention of energy efficient high-density memory devices.
Pulsatile parallel flow of air and a viscoelastic fluid with multiple characteristic times. An application to mucus in the trachea and the frequency of cough
Authors: de la Guerra Pablo Alberto , Corvera Poiré E
Published: May 2022

We study the dynamics of a binary fluid, where the two fluids are flowing parallel to each other in a cylindrical geometry, and driven by a pulsatile pressure gradient. One of the fluids is a low viscosity Newtonian fluid, the other one is viscoelastic. In order to be able to apply the model to different biofluids, we consider that the viscoelastic fluid has several characteristic times. We characterize the dynamics of the fluids as generalized Darcy’s laws, with linear response functions to pulsatile pressure gradients, whose parameters are coupled for both fluids through the fluid–fluid boundary conditions. We apply our results to the dynamics of mucus and air in the trachea and find that the frequency that allows for a larger movement of the mucus, coincides with the experimental frequency of cough. This allows us to propose a plausible explanation for the frequency of cough in healthy individuals, a mechanical process to expel noxious substances from the respiratory system.
Practical application of international recommendations and safety standards in the systematic planning and implementation of remediation of sites or areas with residual radioactive material
Authors: Yankovich T L , Roberts M , Brown J , Mori Y , Williams G A , Charalambous F , Pepin S
Published: May 2022

The IAEA fundamental safety objective is ‘to protect people and the environment from harmful effects of ionizing radiation’ and this must be done ‘without unduly limiting the operation of facilities or the conduct of activities that give rise to radiation risks’, while ensuring that people and the environment, present and future are protected against radiation risks (IAEA 2006 Fundamental Safety Principles, Safety Fundamentals No. SF-1). In addition, ‘protective actions to reduce existing or unregulated radiation risks must be justified and optimized’ (IAEA 2006 Fundamental Safety Principles, Safety Fundamentals No. SF-1). An international system of radiological protection can be applied such that processes, such as remediation, can be systematically undertaken to address the wide range of ‘existing exposure situations’ present globally. In doing so, decisions made regarding actions undertaken can be demonstrated to be ‘justified’ and ‘optimized’ (i.e. balanced), such that the amount of effort should be commensurate with the risk (applying a ’graded approach’). In addition, protection of people and the environment can be demonstrated by comparing the actual exposure to appropriate criteria over the lifetime of remediation. This paper provides an overview of the current IAEA safety standards on remediation of sites or areas contaminated with residual radioactive material within the international system of radiological protection and provides practical examples of their application through case studies considered in IAEA international model validation programs.
Extensional study of optical-flow enhanced hybrid PIV method for dual-plane stereoscopic PIV measurement
Authors: Wang Sirui , Zheng Jianyi , Li Lei , Xia Xi , Han Xiao , Zhang Chi , Qi Fei , Yang Zifeng
Published: May 2022

High-speed dual-plane stereoscopic particle image velocimetry (DP-s-PIV) can capture time-resolved three-component velocity and vorticity vectors in the measurement region, but its spatial resolvability of tiny vortices is blocked by the intrinsic limitation of the cross-correlation evaluation. To overcome this limitation, we propose a scheme to extend the original two-component optical-flow enhanced hybrid PIV method to DP-s-PIV through 3D reconstruction, with its feasibility and resolvability validated through comparison with the cross-correlation evaluation used in DaVis 8.4. The comparisons suggest that the optical-flow enhanced hybrid PIV scheme can greatly improve the spatial resolvability of the velocity field for DP-s-PIV. Moreover, the hybrid scheme can also provide better visualization of vortical structures and enhanced precision in evaluating the vorticity distribution, allowing for further identification of vortex types in a stratified swirling jet flow through the combined criteria (vorticity component and Q criterion).
Tuning electronic, magnetic and catalytic behaviors of biphenylene network by atomic doping
Authors: Ren Kai , Shu Huabing , Huo Wenyi , Cui Zhen , Xu Yujing
Published: May 2022

Recently, a new two-dimensional allotrope of carbon named biphenylene has been experimentally synthesized. First-principles calculations are preformed to investigate the electronic properties of biphenylene and the doping effect is also considered to tune its electronic, magnetic, and catalytic properties. The metallic nature with an n-type Dirac cone is observed in the biphenylene. The magnetism can be induced by Fe, Cl, Cr, and Mn doping. More importantly, the doping position dependence of hydrogen evolution reaction (HER) performance of biphenylene is addressed, which can be significantly improved by atomic doping. In particular, the barrier for HER of Fe doping case is only −0.03 eV, denoting its great potential in HER catalysis.
Single β-Ga2O3 nanowire back-gate field-effect transistor
Authors: Qu Guangming , Xu Siyuan , Liu Lining , Tang Minglei , Wu Songhao , Jia Chunyang , Zhang Xingfei , Song Wurui , Lee Young Jin , Xu Jianlong , Wang Guodong , Ma Yuanxiao , Park Ji-Hyeon , Zhang Yiyun , Yi Xiaoyan , Wang Yeliang , Li Jinmin
Published: May 2022

In this work, a normally-on single-monocrystal β-Ga2O3 nanowire (NW) back-gate field-effect transistor (FET) has been demonstrated by transferring metal-organic chemical vapor deposition-grown β-Ga2O3 NWs on sapphire onto SiO2(300 nm)/p
+-Si substrate. When the gate voltage (V
G) exceeds −14 V, the device is pinched off, with an on/off ratio greater than 108 and a drain leakage current density as low as ∼7.34 fA. The maximum field-effect carrier mobility for these n-doped single β-Ga2O3 NW FETs reaches ∼62.2 cm2 (V s)−1. A prompt degradation in the on/off ratio for these β-Ga2O3 NW back-gate FETs is observed as the operation temperature increased up to 400 K. With strong evidence, the temperature-dependent degradation in the performance is determined by the activation of self-trapped holes and intrinsic vacancy-related defects, both of which would lead to a rapid increase in the channel leakage current at high temperatures.
Investigating the importance of strain-coupling in lead-free 2–2 relaxor/ferroelectric composites with digital image correlation
Authors: Martin Alexander , Maier Juliana G , Streich Friedemann , Kamlah Marc , Webber Kyle G
Published: May 2022

Ceramic–ceramic composite structures are a viable solution to improve the electromechanical response of lead-free ferroelectrics (FEs) through tuning of the local electrical and mechanical fields. The origin of the enhanced properties, however, remains unclear, as many of the possible effects, such as polarization and strain coupling (PSC) as well as interface diffusion, are interrelated and difficult to separate or directly investigate. In this study, we use a custom-built digital image correlation system to directly investigate the influence of strain coupling on 2–2 composites consisting of 0.90Na1/2Bi1/2TiO3–0.06BaTiO3–0.04K0.5Na0.5NbO3 (NBT–6BT–4KNN) and 0.94Na1/2Bi1/2TiO3–0.06BaTiO3 (NBT–6BT) by varying the mechanical interface contacts between end members. Specifically, two model cases were utilized to separate the relative contributions of the PSC mechanisms: (a) electrically connected and (b) mechanically and electrically connected. The local strain gradient was characterized through the thickness of the composite across different layers as well as the interface, where the macroscopic large signal longitudinal and transverse FE response was determined. Experimental results reveal an enhancement of the large signal piezoelectric coefficient

d

33

∗

by approximately 10% from 390 to 440 pm V−1 due to strain coupling.
Investigation of high-energy ultrasonication of RE2BaCuO5(RE = Y, Gd) on the growth and superconducting properties of REBa2Cu3O7−δtop-seeded melt textured bulks
Authors: Pavan Kumar Naik Sugali , Hagiwara Rikako , Ishibashi Shinnosuke , Asano Natsuki , Ogino Hiraku , Ishida Shigeyuki , Koblischka Michael Rudolf , Koblischka-Veneva Anjela , Tsuchiya Yoshinori , Kawashima Kenji , Eisaki Hiroshi , Nishio Taichiro
Published: May 2022

Recently, an improvement in the flux pinning performance ofREBa2Cu3O7−δ(REBCO) bulk was achieved employing high energy ultrasonic irradiation (up to 300 W and 60 min) prior to the infiltration-growth process. Here, we demonstrate that a higher ultrasonic power and shorter duration treatment (450 W for 30 min) of theRE2BaCuO5(RE211,RE= Y, Gd) powder produces individual, nanometer-sized and surface damagedRE211 particles (RE211Ultra). We study the growth of YBCO and GdBCO systems via the top-seeded melt-growth method, with the addition of 30 mol% ofRE211Ultra, which were pre-treated by high-energy ultrasonication and compared with the conventional method. Isothermal growth experiments clarified that the addition ofRE211Ultraparticles enables faster and more effective crystal growth via an improved peritectic reaction due to their size in the nanometer range and presence of sharp edges, which are crucial for growing large, single grain bulks ofREBCO. Microstructural investigations by scanning electron microscopy indicated the presence of two differently sizedRE211 inclusions within the bulk GdBCO and YBCO superconductors. All samples showed an onset of superconductivity at ∼92 K or above. Utilizing the effective growth temperature window and the addition ofRE211Ultra, single grain bulks of GdBCO and YBCO were fabricated by the slow-cooling method. The field dependent critical current density (Jc) of the bulk samples usingRE211Ultrawere found to exhibit superior performance over the standard GdBCO/YBCO samples due to significant changes of sample growth and of their microstructures. Here, we discuss various factors affecting the addition ofRE211Ultraon the development of the microstructure, growth of bulk, single grain materials and further, the superconducting properties of differentREBCO superconductors.
Three-dimensional accurate modeling of nematic liquid crystal based dipole unit for reconfigurable reflectarray at 100 GHz
Authors: Geng Jin-Ling , Song Lizhong
Published: May 2022

In this paper, a three-dimensional accurate modeling of nematic liquid crystal (LC) has been presented for the analysis of reconfigurable reflectarray cells based on LC. Both single-dipole and multiple-dipoles constructed on a LC substrate are designed as the reflectarray unit cell. Considering the inhomogeneous and anisotropic effects, the orientation of the LC molecules at each point of the LC layer involved in the unit cell under the external electrostatic field is obtained by the finite difference numerical modeling method. Utilizing the accurate modeling results of LC, the reflection constants of the reflectarray unit cells have been simulated and also have been compared with that of in the conventional model which usually assumes the LC is homogeneous and isotropic (HOMI). The error of phase range of the unit cell between the two models can exceed 45° in the single-resonant unit cell, and is more than 290° in the multi-resonant unit cell, which will seriously affect the practical application. The permittivity of LC in the unit cells under different applied voltages also has been calculated and given. Moreover, the gain radiation pattern of the reflectarray consisting of the proposed LC based double-dipoles unit cell is simulated in two models. The simulation results show that, in the accurate modeling, the gain and scanning angle range of the reflectarray obtained by the HOMI model change significantly because the phase-shift of the same unit cell for the incident wave is greatly different in the two models, which indicates that the HOMI model can no longer meet the needs of the design of LC based multi-dipoles reflectarray. Therefore, the accurate modeling method needs to be considered and cannot be ignored when studying and designing LC based devices.
Exchange-correlation effects in coupled quantum wire systems at finite temperature
Authors: Sharma Akariti , Garg Vinayak , Moudgil R K
Published: May 2022

We investigate the exchange-correlation effects in coupled quantum wire systems at finite-temperature within the self-consistent mean-field approximation of Singwi et al by assuming the charge carriers to be electrons in one wire and electrons or heavier holes in the other. Numerical results are presented for the intra- and inter-wire static structure factors, pair-correlation functions and the static charge density susceptibility over a wide range of system parameters (viz. temperature T, particle number density and inter-wire spacing) at equal and fixed transverse width of both the wires. We find for the first time that the coupled electron-hole (e-h) quantum wire system may favor a charge-density-wave (CDW) instability at sufficiently low T and carrier density in the close proximity of the wires, where as no such phase transition is observed in the electron-electron (e-e) quantum wire system at any non-zero T. The intra-wire contact pair-correlation functions of both the systems show a non-monotonous behavior with increasing (decreasing) T (carrier number density), and increase consistently with decrease in inter-wire spacing. On the other hand, the corresponding inter-wire contact pair-correlation functions show a non-monotonous T-dependence and consistent increase with decrease in carrier number density and/or inter-wire separation. Results of free exchange-correlation energy for both the e-h and e-e coupled systems are also reported which are found to have a noticeable dependence upon T. To highlight the effect of exchange-correlations, our results have been compared with the predictions of the random-phase approximation (RPA).
Surface plasmon polariton at the interface of dielectric and graphene medium using the Doppler broadening effect
Authors: Ahmad Faizan , Bakhtawar  , Haneef Muhammad , Khan Humayun , Abid Aqsa , Dahshan A
Published: May 2022

We theoretically investigate the control of surface plasmon polariton (SPP) generated at the interface of dielectric and graphene due to effective variation of dielectric functions. The input light pulse is controlled and modified in a Doppler broadening dielectric medium. The controlled and modified output, from Doppler broadening dielectric medium is used to excite SPPs at the interface of graphene and dielectric medium. It is noted that at high Doppler width the absorption/dispersion and propagation length of SPPs become saturated and significantly affected by strength of the control fields. The inverse Doppler effect enhances the group speed of SPPs but suddenly decreases at the region of SPPs hole burning. These results have potential applications in optical tweezers, nano-photonics, radiations guiding, plasmonster technology, photovoltaic devices, data storage devices, biosensor technology and solar cells.
Simulating the perceptual effects of electrode–retina distance in prosthetic vision
Authors: Avraham David , Yitzhaky Yitzhak
Published: May 2022

Objective. Retinal prostheses aim to restore some vision in retinitis pigmentosa and age-related macular degeneration blind patients. Many spatial and temporal aspects have been found to affect prosthetic vision. Our objective is to study the impact of the space-variant distance between the stimulating electrodes and the surface of the retina on prosthetic vision and how to mitigate this impact. Approach. A prosthetic vision simulation was built to demonstrate the perceptual effects of the electrode–retina distance (ERD) with different random spatial variations, such as size, brightness, shape, dropout, and spatial shifts. Three approaches for reducing the ERD effects are demonstrated: electrode grouping (quads), ERD-based input-image enhancement, and object scanning with and without phosphene persistence. A quantitative assessment for the first two approaches was done based on experiments with 20 subjects and three vision-based computational image similarity metrics. Main results. The effects of various ERDs on phosphenes’ size, brightness, and shape were simulated. Quads, chosen according to the ERDs, effectively elicit phosphenes without exceeding the safe charge density limit, whereas single electrodes with large ERD cannot do so. Input-image enhancement reduced the ERD effects effectively. These two approaches significantly improved ERD-affected prosthetic vision according to the experiment and image similarity metrics. A further reduction of the ERD effects was achieved by scanning an object while moving the head. Significance. ERD has multiple effects on perception with retinal prostheses. One of them is vision loss caused by the incapability of electrodes with large ERD to evoke phosphenes. The three approaches presented in this study can be used separately or together to mitigate the impact of ERD. A consideration of our approaches in reducing the perceptual effects of the ERD may help improve the perception with current prosthetic technology and influence the design of future prostheses.
Studies of energetic particle transport induced by multiple Alfvén eigenmodes using neutron and escaping energetic particle diagnostics in Large Helical Device deuterium plasmas
Authors: Ogawa K. , Isobe M. , Kamio S. , Nuga H. , Seki R. , Sangaroon S. , Yamaguchi H. , Fujiwara Y. , Takada E. , Murakami S. , Jo J. , Takemura Y. , Sakai H. , Tanaka K. , Tokuzawa T. , Yasuhara R. , Osakabe M.
Published: May 2022

Studies of energetic particle transport due to energetic-particle-driven Alfvénic instability have progressed using neutron and energetic particle diagnostics in Large Helical Device deuterium plasmas. Alfvénic instability excited by injecting an intensive neutral beam was observed by a magnetic probe and a far-infrared laser interferometer. The interferometer showed Alfvénic instability composed of three modes that existed from the core to the edge of the plasma. A comparison between the observed frequency and shear Alfvén spectra suggested that the mode activity was most likely classified as an Alfvénic avalanche. A neutron fluctuation detector and a fast ion loss detector indicated that Alfvénic instability induced transport and loss of co-going transit energetic ions. The dependence of the drop rate of the neutron signal on the Alfvénic instability amplitude showed that significant transport occurred. Significant transport might be induced by the large amplitude and radially extended multiple modes, as well as a large deviation of the energetic ion orbit from the flux surface.
Upgrade of a quasioptical code PARADE for fusion DEMO: introducing relativistic electron dynamics
Authors: Yanagihara K.
Published: May 2022

Here we report on the upgrade of the quasioptical code PAraxial RAy DEscription (2019 Phys. Plasmas
26 072112) to introduce the relativistic effect for electron cyclotron resonance heating and current drive on fusion DEMO reactors, e.g. JA-DEMO, where the electron temperature is sufficiently high (almost 35 keV). By fully considering the relativistic effect, it is found that the outside launch used in many tokamaks is not suitable for localized heating in JA-DEMOdue to the contamination of spatially widespread absorption at relativistically down-shifted higher-harmonic resonance. It is proposed to adopt a top launch to avoid this issue, and is shown that top launch can improve the localization of the heating without degrading the current drive efficiency.
CIC2: a radiation tolerant 65 nm data aggregation ASIC for the future CMS tracker
Authors: Viret S. , Bergamin G. , Caponetto L. , Caratelli A. , Ceresa D. , Galbit G. , Jain S. , Kloukinas K. , Nodari B. , Scarfi S.
Published: May 2022

The Concentrator Integrated Circuit (CIC) ASIC is a front-end chip for both Pixel-Strip (PS) and Strip-Strip (2S) modules of the future Phase-II CMS Outer Tracker upgrade at the High-Luminosity LHC (HL-LHC). This data aggregator, designed in 65 nm CMOS technology, will be a key element of the tracker front-end chain. A first prototype, CIC1, was tested successfully in early 2019 and was followed by the development of a final radiation tolerant version of the chip: the CIC2. CIC2 design, implementation, and complete test results, are presented.
Scintillator surface modification by glancing angle deposition of thin ZrO2 films
Authors: Azarov I.A. , Kuper K.E. , Lemzyakov A.G. , Porosev V.V. , Shklyaev A.A.
Published: May 2022

In this research, we evaluated the properties of ZrO2
films produced with the glancing angle deposition technique and
evaluated its effect on the detector properties. With using ZrO2,
we created films with a refraction index in the range of 1.3 to 2.0,
and produced a four layer graded-index (GRIN) antireflection
coating. A BGO scintillator sample with an applied GRIN coating
demonstrated up to ∼ 53% light output enhancement in comparison
with the reference ones. For LYSO scintillators, the observed
magnitude of the effect was less, ∼ 11%. Thus, this method is a
technologically applicable way to improve the characteristics of
existing and projected detector systems.
Adhesion behaviors of water droplets on bioinspired superhydrophobic surfaces
Authors: Xu Peng , Zhang Yurong , Li Lijun , Lin Zhen , Zhu Bo , Chen Wenhui , Li Gang , Liu Hongtao , Xiao Kangjian , Xiong Yunhe , Yang Sixing , Lei Yifeng , Xue Longjian
Published: May 2022

The adhesion behaviors of droplets on surfaces are attracting increasing attention due to their various applications. Many bioinspired superhydrophobic surfaces with different adhesion states have been constructed in order to mimic the functions of natural surfaces such as a lotus leaf, a rose petal, butterfly wings, etc. In this review, we first present a brief introduction to the fundamental theories of the adhesion behaviors of droplets on various surfaces, including low adhesion, high adhesion and anisotropic adhesion states. Then, different techniques to characterize droplet adhesion on these surfaces, including the rotating disk technique, the atomic force microscope cantilever technique, and capillary sensor-based techniques, are described. Wetting behaviors, and the switching between different adhesion states on bioinspired surfaces, are also summarized and discussed. Subsequently, the diverse applications of bioinspired surfaces, including water collection, liquid transport, drag reduction, and oil/water separation, are discussed. Finally, the challenges of using liquid adhesion behaviors on various surfaces, and future applications of these surfaces, are discussed.
Drivers of multi-decadal nitrate regime shifts in a large European catchment
Authors: Wachholz Alexander , Jawitz James W , Büttner Olaf , Jomaa Seifeddine , Merz Ralf , Yang Soohyun , Borchardt Dietrich
Published: May 2022

Long-term monitoring shows evidence of persistent changes in the magnitude and timing of the seasonal pattern of nitrate concentrations in streams, with possibly grave effects on aquatic ecosystems. Seasonal patterns of stream nutrient concentrations are determined by a complex interplay of inputs, transport, and turnover. Over multi-decadal periods, each of these factors may change due to socio-economic factors such as consumption patterns, governance regimes, or technological control measures. Here we test the hypothesis that observed multi-decadal changes in stream nitrate seasonality could be explained by changes in the relative importance of catchment nutrient sources over time. We analyze 66 years of shifting nitrate seasonality in a large, central-European river (Elbe) during a period of significant socio-political changes (1954–2019), with correspondingly significant changes in the sources of anthropogenic nitrate emissions. We develop a mixed-source succession model to test how the multi-decadal evolution of the composition of nitrate sources (point and diffuse) influences in-stream seasonality. We show that the in-stream nitrate seasonality of the River Elbe changed significantly from a weak seasonal pattern with peak concentrations during summer in the 1950s to a strong seasonal pattern with peak concentrations during winter in the 1990s. We link these shifts to a succession of technical and political developments which influence the contribution of point and diffuse sources over time. Such shifts in seasonal concentration patterns can significantly impact the macronutrient (carbon, nitrogen, phosphorus) ratios in rivers, which in turn highly affect the health of aquatic ecosystems.
The mean and variance of the distribution of shortest path lengths of random regular graphs
Authors: Tishby Ido , Biham Ofer , Kühn Reimer , Katzav Eytan
Published: May 2022

The distribution of shortest path lengths (DSPL) of random networks provides useful information on their large scale structure. In the special case of random regular graphs (RRGs), which consist of N nodes of degree c ⩾ 3, the DSPL, denoted by P(L = ℓ), follows a discrete Gompertz distribution. Using the discrete Laplace transform we derive a closed-form (CF) expression for the moment generating function of the DSPL of RRGs. From the moment generating function we obtain CF expressions for the mean and variance of the DSPL. More specifically, we find that the mean distance between pairs of distinct nodes is given by

⟨

L

⟩

=

ln

N

ln

(

c
−
1

)

+

1

2

−

ln

c
−
ln

(

c
−
2

)

+
γ

ln

(

c
−
1

)

+
O

ln

N

N

, where γ is the Euler–Mascheroni constant. While the leading term is known, this result includes a novel correction term, which yields very good agreement with the results obtained from direct numerical evaluation of ⟨L⟩ via the tail-sum formula and with the results obtained from computer simulations. However, it does not account for an oscillatory behavior of ⟨L⟩ as a function of c or N. These oscillations are negligible in sparse networks but detectable in dense networks. We also derive an expression for the variance Var(L) of the DSPL, which captures the overall dependence of the variance on c but does not account for the oscillations. The oscillations are due to the discrete nature of the shell structure around a random node. They reflect the profile of the filling of new shells as N is increased. The results for the mean and variance are compared to the corresponding results obtained in other types of random networks. The relation between the mean distance and the diameter is discussed.
Nucleation and growth of ellipsoidal crystals in a supercooled binary melt
Authors: Nikishina M A , Alexandrov D V
Published: May 2022

When considering the evolution of particulate assemblages in supercooled and supersaturated liquids, the shape of crystals often differs from spherical. Existing experiments show that evolved crystals often are ellipsoidal. Motivated by important applications in materials physics, chemistry, and biophysics, we develop here a growth theory of a polydisperse ensemble of ellipsoidal crystals in a binary supercooled melt. An integro-differential model of kinetic and balance equations supplemented by initial and boundary conditions that describe desupercooling dynamics and particle-volume distribution function with allowance for the ellipsoidal shape of growing crystals is formulated and solved analytically using the saddle-point technique for a Laplace-type integral. The distribution function increases up to the maximal volume of particles and shifts to larger crystal volumes with time. The solute concentration substantially changes the evolution of a particulate assemblage. The melt supercooling decays faster and the particle-volume distribution function is lower with increasing the initial solute concentration. The theory under consideration generalizes previously developed growth theories for spherical crystals in a binary melt (Alexandrov 2014 J. Phys. A: Math. Theor.
47 125102) and ellipsoidal crystals in a single-component melt (Nikishina and Alexandrov 2021 Phil. Trans. R. Soc. A
379 20200306).
Sliding wear response of ultrasonic-assisted stir-squeeze cast Al-Zn(-Mg) alloy/ZrO2p composite: wear mechanism and subsurface deformation
Authors: Singh Ashish Kumar , Soni Sanjay , Rana Ravindra Singh
Published: May 2022

The character of hard ZrO2p in dry sliding wear of Al-Zn(-Mg) alloy was investigated in the cast and heat-treated conditions using a pin-on-disc wear tester at fixed sliding speed (3.5 m s−1) and varying applied pressure (0.5–2.125 MPa), giving special accentuation on the response parameters such as seizure resistance, wear rate, and bulk temperature rise. Hardness behavior was also studied for the same concerning materials in accordance with ASTM standards. The composites exhibited enhanced hardness, wear and seizure resistance, and greater temperature rise over the alloy. Indeed, the wear rate at preliminary stages increased with increasing applied pressure up to a transition limit beyond which it upsurged abruptly to greater value at the seizure pressure. Heat treatment also significantly improved the hardness, and resistance to wear and seizure. Amongst, heat-treated composite embedded with 4% ZrO2p yielded the highest hardness of 180 HV and seizure pressure of 2.125 MPa, respectively. The deformation in the subsurface was examined in terms of microhardness variation along the depth perpendicular to the worn surface. It was detected that the presence of ZrO2p not only enhanced the seizure resistance but also effectively hampered the extent of subsurface deformation at the seizure. The wear mechanism was prevalently governed through the establishment of the mechanically mixed layer (MML), oxide layer, cracking, and deformed subsurface.
Electrically switchable giant Berry curvature dipole in silicene, germanene and stanene
Authors: Bandyopadhyay Arka , Joseph Nesta Benno , Narayan Awadhesh
Published: May 2022

The anomalous Hall effect in time-reversal symmetry broken systems is underpinned by the concept of Berry curvature in band theory. However, recent experiments reveal that the nonlinear Hall effect (NHE) can be observed in non-magnetic systems without applying an external magnetic field. The emergence of NHE under time-reversal symmetric conditions can be explained in terms of non-vanishing Berry curvature dipole (BCD) arising from inversion symmetry breaking. In this work, we availed realistic tight-binding models, first-principles calculations, and symmetry analyses to explore the combined effect of transverse electric field and strain, which leads to a giant BCD in the elemental buckled honeycomb lattices—silicene, germanene, and stanene. The external electric field breaks the inversion symmetry of these systems, while strain helps to attain an asymmetrical distribution of Berry curvature of a single valley. Furthermore, the topology of the electronic wavefunction switches from the band inverted quantum spin Hall state to normal insulating one at the gapless point. This band gap closing at the critical electric field strength is accompanied by an enhanced Berry curvature and concomitantly a giant BCD at the Fermi level. Our results predict the occurrence of an electrically switchable nonlinear electrical and thermal Hall effect in a new class of elemental systems that can be experimentally verified.
State of the art review on the sustainable dry machining of advanced materials for multifaceted engineering applications: progressive advancements and directions for future prospects
Authors: Singh Jasjeevan , Gill Simranpreet Singh , Dogra Manu , Singh Rupinder , Singh Malkeet , Sharma Shubham , Singh Gursharan , Li Changhe , Rajkumar S
Published: May 2022

In this article, the comprehensive review on the application, and indeed, a comparative analysis on dry machining of different types of materials (Inconel, steel, aluminum, cast iron, magnesium and advanced materials) used in machining (turning, drilling and milling operations) were carried out in the light of utmost works published in the literature. The work describes the scientific findings of the past twenty years, including sustainable methods (surface texture, solid lubricants, vibration-assisted machining, laser-assisted machining), tool coatings, and geometry of tools. Vibration-assisted machining is another direction that researchers have investigated without the use of cutting coolants, where the complete disposal of coolants is not possible. Various researchers have carried out rigorous experimental work on milling, drilling, and turning operations under dry conditions to machine numerous materials. A significant proportion of experimental data about tool wear, tool wear machining, surface quality, surface integrity, etc, has been analyzed under dry conditions. However, the critical analysis of dry machining for different conventional machining operations for a variety of industrial materials is still lacking for establishing dry machining as a sustainable process for industrial applications. Thus, the critical analysis of various machining parameters and their consequences on tool wear and the surface quality of machined work was carried out in this work. Finally, scientific recommendations based on critical findings were proposed for industrial implementation of dry machining.
Monodispersed ZnO nanoink and ultra-smooth large-area ZnO films for high performance and stable organic solar cells
Authors: Guo Jingbo , Han Yunfei , Xu Zihan , Zha Wusong , Fang Jin , Luo Qun , Liu Liqi , Ma Chang-Qi
Published: May 2022

In the organic solar cells (OSCs), zinc oxide nanoparticles (ZnO NPs) have been widely used to fabricate electron transporting layer (ETL). However, spontaneous aggregation of NPs and film surface defects are two issues that limit the application of ZnO NPs in the printed photovoltaics. To simultaneously solve the two problems, the ZnO nanoinks were modified with a 2-(2-methoxyethoxy) acetic acid (MEA) solution, in which a monodispersed nanoink was obtained, and no aggregation occurred after 18 months of storage at room temperature. Meanwhile, the ZnO:MEA ETL had fewer surface hydroxyl groups defects because of Lewis acid-base interactions. The monodispersibility and passivated surface defects ensured an ultra-smooth ZnO film, leading to an improved device performance, longer lifetime, and higher thickness tolerance. As a result, an efficiency of 15.84% was achieved for the 1 cm2 PM6:Y6 ZnO:MEA ETL-based OSCs, and the T
80 lifetime was also increased to 6600 h. The thickness of ZnO:MEA ETL could be increased to 225 nm with less performance degradation. ZnO:MEA NPs were dispersed well in alcohols with high boiling points, which ensured a high-quality slot-die coated film. The ZnO:MEA ETL also has a unique advantage in flexible organic OSCs, with enhanced bending resistance during 10000 times bending. These properties demonstrated the great potential of ZnO:MEA nanoinks in the printed electronics.
Predicting the thermal expansion of body-centred cubic (BCC) high entropy alloys in the Mo–Nb–Ta–Ti–W system
Authors: Wilson Jack A , Evitts Lee J , Fraile Alberto , Wilson Roy E , Rushton Michael J D , Goddard David T , Lee William E , Middleburgh Simon C
Published: May 2022

In this study, the thermal expansion behaviour of equiatomic alloys in the Mo–Nb–Ta–Ti–W system is studied to provide a predictive method to assess the behaviour of this and other high entropy alloy systems. The simulations used are based on first principles density functional perturbation theory and the quasi-harmonic approximation. Calculations have been used to predict the stability and phonon properties of increasingly complex alloys in the Mo–Nb–Ta–Ti–W system and their thermal expansion coefficients have been predicted. These are benchmarked against rule-of-mixtures predictions and experimental observations, where available. We have shown that atomic-scale modelling techniques can be used to reliably predict the thermal expansion of a range of body-centred cubic high entropy alloys and concentrated solid solutions.
Design of a low-cost welding machine controller with a novel control algorithm for an enhanced HF TIG welding process
Authors: Sahane Dnyaneshwar Vitthal , Ghate Pravin M , Paithane Ajay N
Published: May 2022

Automation plays an important role in event welding domain. This paper describes the problems associated with arc tungsten inert gas (TIG) welding for automated welding in oil and gas industry for pipe joints. Welding joints inside the offshore pipelines is a complex process and rework or repetitive work is very costly. Weld imperfections are the foremost anxiety in the pipe joint welding. Return out the entire weld machine to find the defect at the time of welding. This is one of the popular industry come with the problem statement to develop the application specific solution for inner pipe welding quality welding. However, this paper gives the solution. Moreover, factors like Joint crack, moisture, corrugated weld object, excessive gas flow, Lack of fusion in the root, Dirty base or filler metal are major problems in the welding process. Due to these issues weld quality is impacted. There are several problem areas in the existing welding control system i.e., poor topology selection, less efficiency, high power loss, more size, high cost, more maintenance, less effective control algorithm for welding control etc Due to all these factors the welding quality is hampered in traditional welding system. Many researchers have worked on the power electronics hardware section improvement but very less work done on the software section. This paper discusses on the software algorithm development and how the weld quality improved. Software welding algorithm development is the novelty of this paper. This paper proposed and developed low-cost welding machine controller using STM32F103 microcontroller with protection scheme. A welding algorithm is proposed and experimented to enhance arc TIG welding quality and automation. Welding algorithm is tested & practically verified using phase-shifted full bridge (PSFB) power converter topology with pulse width modulation (PWM) control technology. The results reveal that the proposed algorithm significantly improves the quality of automated welding.