bluuebunny/crossref_metadata_2025 huggingface dataset:
Sub-10 nm metal nanogaps with high SERS performance via a novel conformal coating process
Authors: Wang Yasi , Huang Shengchao , He Jianbo , Zhu Xupeng , Shi HuiMin
Published: March 2023

Metallic nanogaps enables inducing the strong coupling between neighboring metal structures, resulting in a great field enhancement in the gap. Therefore, it is crucial fundamental building blocks for nanoelectronics and nanophotonics. Moreover, the electromagnetic field enhancement of the tiny gap increases rapidly with the decrease of gaps size. Naturally, enables better device performance with higher field enhancements. However, as the size of nanogaps reduced to the sub-10 nm scale, the fabrication of metallic nanogaps faced with great challenges, including the decrease in uniformity, repeatability and stability of the fabricating process due to various manufacturing and physical constraints. Thus, how to further reduce the size of metal nanogaps for higher device performance has become a key issue in this field. In this work, we propose and demonstrate a novel approach to fabricate sub-10 nm metal nanogaps by coating a conformal ultrathin oxide film via atomic-layer deposition. The method can fabricate sub-10 nm gap in dense metal-nanostructure arrays with high stability, reliability and uniformity, which provides a reliable technical for the fabrication and application of high-performed metallic nanogap structures and devices.
Chiral-coupling-assisted refrigeration in trapped ions
Authors: Chen Chi-Chih , Wang Yi-Cheng , Wang Chun-Che , Jen H H
Published: March 2023

Trapped ions can be cooled close to their motional ground state, which is imperative in implementing quantum computation and quantum simulation. Here, we theoretically investigate the capability of light-mediated chiral couplings between ions to enable a superior cooling scheme exceeding the single-ion limit of sideband cooling. Under asymmetric driving, the target ion manifests the chiral-coupling-assisted refrigeration at the price of heating others, where its steady-state phonon occupation outperforms the lower bound set by a single ion. We further explore the optimal operation conditions for the refrigeration where a faster rate of cooling can still be sustained. Under an additional nonguided decay channel, a broader parameter regime emerges to support the superior cooling and carries over into the reciprocal coupling, suppressing the heating effect instead. Our results present a tunable resource of collective chiral couplings which can help surpass the bottleneck of the cooling procedure and open up new possibilities in applications of trapped-ion-based quantum computation and simulation.
Insights into selected 2D piezo Rashba semiconductors for self-powered flexible piezo spintronics: material to contact properties
Authors: IS Fathima , Mohanta Manish Kumar , Sarkar Abir De
Published: March 2023

The new paradigm in electronics consists in realizing the seamless integration of many properties latent in nanomaterials, such as mechanical flexibility, strong spin–orbit coupling (Rashba spin splitting—RSS), and piezoelectricity. Taking cues from the pointers given on 1D ZnO nanowires (ACS Nano 2018 12 1811–20), the concept can be extended to multifunctional two-dimensional (2D) materials, which can serve as an ideal platform in next-generation electronics such as self-powered flexible piezo-spintronic device. However, a microscopically clear understanding reachable from the state-of-the-art density functional theory-based approaches is a prerequisite to advancing this research domain. Atomic-scale insights gained from meticulously performed scientific computations can firmly anchor the growth of this important research field, and that is of undeniable relevance from scientific and technological outlooks. This article reviews the scientific advance in understanding 2D materials hosting all the essential properties, i.e. flexibility, piezoelectricity, and RSS. Important 2D semiconducting monolayers that deserve a special mention, include monolayers of buckled MgX (X = S, Se, Te), CdTe, ZnTe, Janus structures of transition metal trichalcogenides, Janus tellurene and 2D perovskites. van Der Waals multilayers are also built to design multifunctional materials via modulation of the stacking sequence and interlayer coupling between the constituent layers. External electric field, strain engineering and charge doping are perturbations mainly used to tune the spintronic properties. Finally, the contact properties of these monolayers are also crucial for their actual implementation in electronic devices. The nature of the contacts, Schottky/Ohmic, needs to be carefully examined first as it controls the device’s performance. In this regard, the rare occurrence of Ohmic contact in graphene/MgS van der Waals hetero bilayer has been presented in this review article.
The spin polarization of palladium on magneto-electric Cr2O3
Authors: Komesu Takashi , Echtenkamp Will , Binek Christian , Dowben Peter A
Published: March 2023

While induced spin polarization of a palladium (Pd) overlayer on antiferromagnetic and magneto-electric Cr2O3(0001) is possible because of the boundary polarization at the Cr2O3(0001), in the single domain state, the Pd thin film appears to be ferromagnetic on its own, likely as a result of strain. In the conduction band, we find the experimental evidence of ferromagnetic spin polarized in Pd thin films on a Cr2O3(0001) single crystal, especially in the thin limit, Pd thickness of around 1–4 nm. Indeed there is significant spin polarization in 10 Å thick Pd films on Cr2O3(0001) at 310 K, i.e. above the Néel temperature of bulk Cr2O3. While Cr2O3(0001) has surface moments that tend to align along the surface normal, for Pd on Cr2O3, the spin polarization contains an in-plane component. Strain in the Pd adlayer on Cr2O3(0001) appears correlated to the spin polarization measured in spin polarized inverse photoemission spectroscopy. Further evidence for magnetization of Pd on Cr2O3 is provided by measurement of the exchange bias fields in Cr2O3/Pd(buffer)/[Co/Pd]
n
exchange bias systems. The magnitude of the exchange bias field is, over a wide temperature range, virtually unaffected by the Pd thickness variation between 1 and 2 nm.
Imaging of intracerebral hemorrhage with adaptive genetic algorithm in brain electrical impedance tomography
Authors: Shi Yanyan , Liu Zhenkun , Fu Feng , Wang Meng , Lou Yajun , Zheng Shuo
Published: March 2023

Intracerebral hemorrhage refers to bleeding caused by the spontaneous rupture of blood vessels. Accurate diagnosis of hemorrhage is vital in the treatment of a patient. As a new medical imaging technique, electrical impedance tomography (EIT) is able to offer images of conductivity distribution variation caused by pathological change. However, image reconstruction of EIT suffers from the problem of serious ill-posedness. In particular, in brain imaging, irregular and multi-layered head structure together with the low conductivity of the skull further aggravate the problem. In order to address this problem, a new image-reconstruction method is proposed for imaging of hemorrhage in this work. With current solutions solving by a Tikhonov regularization method for the original conductivity distribution, the proposed method enhances the reconstruction quality by introducing an adaptive genetic algorithm. To test the performance of the proposed method, simulation work is conducted. A three-layer head model is established and an inclusion, which simulates hemorrhage, is placed at six different locations in the brain layer. Images reconstructed by the Tikhonov method, Newton–Raphson method and the traditional genetic algorithm are used for comparisons. Quantitative evaluation is also performed. The anti-noise performance of the proposed method is estimated by considering noise with differing signal-to-noise ratios. In addition to simulation, phantom experiments are carried out to further verify the performance of the proposed method. The results show that the proposed method performs well in the reconstruction of simulated intracerebral hemorrhage. With the proposed method, the inclusion can be more accurately reconstructed and the background is much clearer than the other three traditional methods.
A probabilistic deep learning model of inter-fraction anatomical variations in radiotherapy
Authors: Pastor-Serrano Oscar , Habraken Steven , Hoogeman Mischa , Lathouwers Danny , Schaart Dennis , Nomura Yusuke , Xing Lei , Perkó Zoltán
Published: March 2023

Objective. In radiotherapy, the internal movement of organs between treatment sessions causes errors in the final radiation dose delivery. To assess the need for adaptation, motion models can be used to simulate dominant motion patterns and assess anatomical robustness before delivery. Traditionally, such models are based on principal component analysis (PCA) and are either patient-specific (requiring several scans per patient) or population-based, applying the same set of deformations to all patients. We present a hybrid approach which, based on population data, allows to predict patient-specific inter-fraction variations for an individual patient. Approach. We propose a deep learning probabilistic framework that generates deformation vector fields warping a patient's planning computed tomography (CT) into possible patient-specific anatomies. This daily anatomy model (DAM) uses few random variables capturing groups of correlated movements. Given a new planning CT, DAM estimates the joint distribution over the variables, with each sample from the distribution corresponding to a different deformation. We train our model using dataset of 312 CT pairs with prostate, bladder, and rectum delineations from 38 prostate cancer patients. For 2 additional patients (22 CTs), we compute the contour overlap between real and generated images, and compare the sampled and ‘ground truth’ distributions of volume and center of mass changes. Results. With a DICE score of 0.86 ± 0.05 and a distance between prostate contours of 1.09 ± 0.93 mm, DAM matches and improves upon previously published PCA-based models, using as few as 8 latent variables. The overlap between distributions further indicates that DAM’s sampled movements match the range and frequency of clinically observed daily changes on repeat CTs. Significance. Conditioned only on planning CT values and organ contours of a new patient without any pre-processing, DAM can accurately deformations seen during following treatment sessions, enabling anatomically robust treatment planning and robustness evaluation against inter-fraction anatomical changes.
An artificial intelligence-based model for cell killing prediction: development, validation and explainability analysis of the ANAKIN model
Authors: Cordoni Francesco G , Missiaggia Marta , Scifoni Emanuele , La Tessa Chiara
Published: March 2023

The present work develops ANAKIN: an Artificial iNtelligence bAsed model for (radiation-induced) cell KIlliNg prediction. ANAKIN is trained and tested over 513 cell survival experiments with different types of radiation contained in the publicly available PIDE database. We show how ANAKIN accurately predicts several relevant biological endpoints over a wide broad range on ion beams and for a high number of cell-lines. We compare the prediction of ANAKIN to the only two radiobiological models for Relative Biological Effectiveness prediction used in clinics, that is the Microdosimetric Kinetic Model and the Local Effect Model (LEM version III), showing how ANAKIN has higher accuracy over the all considered cell survival fractions. At last, via modern techniques of Explainable Artificial Intelligence (XAI), we show how ANAKIN predictions can be understood and explained, highlighting how ANAKIN is in fact able to reproduce relevant well-known biological patterns, such as the overkilling effect.
Inter-fraction deformable image registration using unsupervised deep learning for CBCT-guided abdominal radiotherapy
Authors: Xie Huiqiao , Lei Yang , Fu Yabo , Wang Tonghe , Roper Justin , Bradley Jeffrey D , Patel Pretesh , Liu Tian , Yang Xiaofeng
Published: March 2023

Objective. CBCTs in image-guided radiotherapy provide crucial anatomy information for patient setup and plan evaluation. Longitudinal CBCT image registration could quantify the inter-fractional anatomic changes, e.g. tumor shrinkage, and daily OAR variation throughout the course of treatment. The purpose of this study is to propose an unsupervised deep learning-based CBCT-CBCT deformable image registration which enables quantitative anatomic variation analysis. Approach. The proposed deformable registration workflow consists of training and inference stages that share the same feed-forward path through a spatial transformation-based network (STN). The STN consists of a global generative adversarial network (GlobalGAN) and a local GAN (LocalGAN) to predict the coarse- and fine-scale motions, respectively. The network was trained by minimizing the image similarity loss and the deformable vector field (DVF) regularization loss without the supervision of ground truth DVFs. During the inference stage, patches of local DVF were predicted by the trained LocalGAN and fused to form a whole-image DVF. The local whole-image DVF was subsequently combined with the GlobalGAN generated DVF to obtain the final DVF. The proposed method was evaluated using 100 fractional CBCTs from 20 abdominal cancer patients in the experiments and 105 fractional CBCTs from a cohort of 21 different abdominal cancer patients in a holdout test. Main Results. Qualitatively, the registration results show good alignment between the deformed CBCT images and the target CBCT image. Quantitatively, the average target registration error calculated on the fiducial markers and manually identified landmarks was 1.91 ± 1.18 mm. The average mean absolute error, normalized cross correlation between the deformed CBCT and target CBCT were 33.42 ± 7.48 HU, 0.94 ± 0.04, respectively. Significance. In summary, an unsupervised deep learning-based CBCT-CBCT registration method is proposed and its feasibility and performance in fractionated image-guided radiotherapy is investigated. This promising registration method could provide fast and accurate longitudinal CBCT alignment to facilitate inter-fractional anatomic changes analysis and prediction.
Design of a generic method for single dual-tracer PET imaging acquisition in clinical routine
Authors: Taheri Nasrin , Le Crom Benjamin , Bouillot Caroline , Chérel Michel , Costes Nicolas , Gouard Sébastien , Marionneau-Lambot Séverine , Merlin Thibault , Visvikis Dimitris , Stute Simon , Carlier Thomas
Published: March 2023

Using different tracers in positron emission tomography (PET) imaging can bring complementary information on tumor heterogeneities. Ideally, PET images of different tracers should be acquired simultaneously to avoid the bias induced by movement and physiological changes between sequential acquisitions. Previous studies have demonstrated the feasibility of recovering separated PET signals or parameters of two or more tracers injected (quasi-)simultaneously in a single acquisition. In this study, a generic framework in the context of dual-tracer PET acquisition is proposed where no strong kinetic assumptions nor specific tuning of parameters are required. The performances of the framework were assessed through simulations involving the combination of [18F]FCH and [18F]FDG injections, two protocols (90 and 60 min acquisition durations) and various activity ratios between the two injections. Preclinical experiments with the same radiotracers were also conducted. Results demonstrate the ability of the method both to extract separated arterial input functions (AIF) from noisy image-derived input function and to separate the dynamic signals and further estimate kinetic parameters. The compromise between bias and variance associated with the estimation of net influx rate K

i
shows that it is preferable to use the second injected radiotracer with twice the activity of the first for both 90 min [18F]FCH+[18F]FDG and 60 min [18F]FDG+[18F]FCH protocols. In these optimal settings, the weighted mean-squared-error of the estimated AIF was always less than 7%. The K

i
bias was similar to the one of single-tracer acquisitions; below 5%. Compared to single-tracer results, the variance of K

i
was twice more for 90 min dual-tracer scenario and four times more for the 60 min scenario. The generic design of the method makes it easy to use for other pairs of radiotracers and even for more than two tracers. The absence of strong kinetic assumptions and tuning parameters makes it suitable for a possible use in clinical routine.
Charge transfer and ionization cross-sections in collisions of singly charged lithium ions with helium and nitrogen atoms
Authors: Al-Ajaleen M , Taoutioui A , Tőkési K
Published: March 2023

We present a non-perturbative classical treatment of the charge transfer and ionization processes in collisions between singly charged lithium ions with helium and nitrogen atomic targets. Single capture and single ionization total cross sections are calculated using a three-body classical trajectory Monte Carlo (CTMC) method in which the interaction between the collision partners is described by a Garvey-type model potential. The cross sections are evaluated for collision energies between 20 keV and 100 MeV. In particular, we found excellent agreement between our results and the available experimental data for the case of the single capture of He(1s) by Li+ ions. In addition, our CTMC results are in a reasonable agreement with the experimental results for collision energies higher than 200 keV for single capture of N(2p) atoms by Li+. Furthermore, we present single ionization cross sections for both collision systems.
Excitation of toroidal Alfvén eigenmode by barely circulating energetic electrons in low density plasmas
Authors: Wang Tao , Zhu Xiang , Zeng Long , Briguglio Sergio , Vlad Gregorio , Zonca Fulvio , Qiu Zhiyong
Published: March 2023

Toroidal Alfvén eigenmodes (TAEs) associated with runaway electrons are observed in low density EAST Ohmic discharges (Zhu et al 2022 Phys. Plasmas
29 062504), which motivate the present work to explore the possible destabilization mechanism using simplified hybrid MHD-kinetic simulations. We show that the barely circulating energetic electrons can satisfy the resonance condition with the TAE, mainly due to vanishing transit frequency near the phase space circulating/trapped separatrix. In addition, the nonlinear saturation study suggests that the phase space resonance structure plays an important role in the eventual saturation amplitude, where a low toroidal mode number is favored in this scenario.
Three-dimensional analysis of RF-biased ion optics with misalignments of apertures
Authors: Li Yifei , Wang Weizong , Liu Wei , Dong Yicheng , Fu Chencong
Published: March 2023

Accelerator grid hole shift is a critical reason for erosion failure of optic systems in ion thrusters, which may also cause an unexpected roll torque about the ion beam axis. A three-dimensional (3D) model of ion optics is developed based on a particle-in-cell Monte Carlo collision method to investigate the plasma dynamics and performance of radio frequency (RF) grid systems with misalignments of apertures, which are compared with those in the direct current (DC) grid system. For the benchmark case, the 3D model gives a better agreement with the experiments in the ion energy distribution function (IEDF) compared with the two-dimensional model from a previous publication, with 36.4% and 47.9% relative error reduction of the peak position and full width at half maximum (FWHM), respectively, indicating the effectiveness of the developed 3D model. Simulations show that in the RF grid system the ion beamlet is deflected in the direction opposite to the shift of the accelerator grid hole, while electrons move first in the hole shift direction, and then deflect in the opposite direction. The average ion beamlet deflection angle calculated is consistent with the predictions from linear optical theory in both the RF and DC grid system. The amplitude of beamlet deflection angle fluctuation with time decreases with the increase of RF frequency. When the grid holes shift, the ion beamlet will deflect with the divergence angle almost unchanged in the DC grid system, while the beamlet divergence angle increases in the RF grid system. When RF frequency is low, the big vortex-like structure in the electron velocity phase diagram breaks into small vortices, showing a reduced oscillation intensity. The hole shift also causes high-frequency oscillation in the shift direction. In terms of performance, the RF grid system is more sensitive to grid hole shift than the DC grid system.
Power concentration determined by thermodynamic properties in complex gas mixtures: the case of plasma-based dry reforming of methane
Authors: Biondo Omar , Hughes Ashley , van de Steeg Alex , Maerivoet Stein , Loenders Björn , van Rooij Gerard , Bogaerts Annemie
Published: March 2023

We investigate discharge contraction in a microwave plasma at sub-atmospheric pressure, operating in CO2 and CO2/CH4 mixtures. The rise of the electron number density with plasma contraction intensifies the gas heating in the core of the plasma. This, in turn, initiates fast core-periphery transport and defines the rate of thermal chemistry over plasma chemistry. In this context, power concentration describes the overall mechanism including plasma contraction and chemical kinetics. In a complex chemistry such as dry reforming of methane, transport of reactive species is essential to define the performance of the reactor and achieve the desired outputs. Thus, we couple experimental observations and thermodynamic calculations for model validation and understanding of reactor performance. Adding CH4 alters the thermodynamic properties of the mixture, especially the reactive component of the heat conductivity. The increase in reactive heat conductivity increases the pressure at which plasma contraction occurs, because higher rates of gas heating are required to reach the same temperature. In addition, we suggest that the predominance of heat conduction over convection is a key condition to observe the effect of heat conductivity on gas temperature.
A piezoelectric energy harvester with inner beam adapting to low and high wind speeds: modeling, simulation and experiment
Authors: Jia Jinda , Shan Xiaobiao , Xie Tao
Published: March 2023

Traditional vortex-induced vibration energy harvesters could transform wind or water energy into electricity at low flowing speeds. However, it has the disadvantage of narrow working speed band, which limits wide application in velocity-changing environments. A piezoelectric harvester with an inner beam for harvesting wind energy at both low and high wind speed regions is presented. A comprehensive nonlinear distributed fluid–solid–electric governing equations for vortex-induced vibration piezoelectric energy harvesting are derived and the theoretical results show that dimensions of outer beam and diameter of attached cylinder can affect optimal wind speed and maximum power output at both low and high wind speeds. In contrast, the dimensions of the inner beam and mass block only have impacts at high wind speeds. The equivalent circuit modeling method is utilized to analyze energy harvesting output characteristics. Analogies between mechanical and electrical domains are built, and the governing equations are converted to circuit equations. Then the circuit equations are settled in electrical software for time-varying analysis. The electrical circuit simulation results show that the optimal load resistance is 400 kΩ at low wind speed and 500 kΩ at low wind speed, which is consistent with theoretical results. The prototypes were fabricated and experiments were carried out in a wind tunnel. Experimental results indicate that energy harvester could generate power at both low and high speeds. Mass block has great impact on optical speed and working wind speed band. The energy harvester with 7.06 g mass block could output 127.36 μW at 2.65 m s−1 and 63.63 μW at 4.4 m s−1. Numerical and circuit simulation results are consistent with experimental results on optical load resistances and optical wind speeds. This design provides a feasible method for broadening wind speed region for energy harvesting.
Tunneling and entropy analysis of parameterized black hole with rotating case
Authors: Asgher Muhammad , Karamat Anosha , Babar Rimsha , Ali Riasat
Published: March 2023

In this work, we study the parameterized black hole solution by applying the Newman-Janis approach and also examine the Hawking temperature. We consider a Lagrangian field equation associated with the generalized uncertainty principle to study the motion of boson particles. By using semi-classical phenomenon, we analyze the modified Hawking temperature and graphically check the effects of deformation, rotation and correction parameter on black hole geometry. Furthermore, we investigate the logarithmic corrected entropy and also analyze the graphical behavior of deformation and quantum gravity parameter on the logarithmic corrected entropy of black hole.
To investigate the structural, electronic, optical and magnetic properties of Sr-doped KNbO3 for perovskite solar cell applications: A DFT study
Authors: Jameel Muhammad Hasnain , Rehman Azka , bin Roslan Muhammad Sufi , Agam Mohd Arif Bin
Published: March 2023

A First-principles research based on density functional theory is used to explore the various properties of pure and Sr-doped-KNbO3-perovskites compounds such as structural, electronic, magnetic, and optical characteristics. The Sr impact on structural, optical, electronic, and magnetic properties of Sr-doped-KNbO3 are investigated using ultra-soft pseudo-potential. The band gap of Sr-doped-KNbO3 is found to be remarkably increased from 1.50 eV to 1.83 eV after the doping of Strontium (Sr) with various percentages (0%, 12.5%, 25%, 37.5%). Under the DFT study, strontium(Sr) is appropriate material for increasing the band gap of KNbO3. Owing to the difference in ionic radii of Mo and Sr volume of crystal cells also decreased from 82.68 to 42.89 A3 after the doping of Strontium (Sr). The bandgap nature is found indirect furthermore bandgap showed that the material is a prominent semiconductor. A significant increment is obtained in the optical conductivity and also bandgap. After the doping of strontium (Sr) impurities, the energy absorption peaks are amplified. It is also observed that due to Sr substitution optical conductivity shifted toward higher energies. Sr-doped-KNbO3 has enhanced optical conductivity, energy absorption, and refractive index, making it an appropriate material for perovskite solar cell applications.
Light-induced switch based on edge modes in irradiated thin topological insulators
Authors: Askarpour Zahra , Cheraghchi Hosein
Published: March 2023

We investigate transport properties through the nano-ribbons of thin topological insulators irradiated by circularly polarized light in a high-frequency regime. It is demonstrated that pseudo-spin polarized edge modes appearing in the bulk band gap are responsible for the current flowing through this nano-junction whose localization on the top and bottom edges depend strongly on the polarization of light. Based on these edge modes, one can design a light-induced switch with a desirable on/off ratio of the current whose off-state is engineered by dividing the scattering region into two parts. Each part is irradiated by the light with opposite polarization in respect to the other one. This off-state arises from the quantum blocking of transition between two edge modes with opposite pseudo-spin polarization induced by irradiation. The local current on each bond shows how the current passes through the edges and jumps to the opposite edge. Furthermore, some other nano-junctions are proposed as a light-induced switch which are designed based on the gap opening induced by the perpendicular magnetization or structural inversion asymmetry.
Trap sensitivity of splitted source Z Shape horizontal pocket and hetero stack TFETs: a simulation study
Authors: Tiwari Shreyas , Saha Rajesh
Published: March 2023

This paper reports the trap sensitivity analysis of split source horizontal pocket Z shape tunnel field effect transistor (ZHP-TFET) and hetero stack TFET (HS-TFET) using technology computer aided design (TCAD) simulator. The sensitivity analysis elaborates the significance of ideal trap charges at the interface of oxide and semiconductor material for both acceptor and donor like traps. The trap sensitivity analysis is highlighted for variation in trap-concentrations, temperature, gate-metal work function, and peak energy position, for both the TFETs. Furthermore, we have implemented digital inverter on taking into account the interface trap charges effect. Result reveals that tarp sensitivity on various electrical parameter of HS-TFET is significantly higher than ZHP-TFET. It is seen that ZHP-TFET provides sensitivity around 11 and 33 under acceptor and donor impurities, respectively, whereas, for HS-TFET sensitivity is around 22 and 60 for acceptor and donor impurities, respectively, for wide variation in trap concentration. The voltage transfer characteristic and voltage gain of digital inverter are improved by observable amount in ZHP-TFET than HS-TFET for both donor and acceptor like trap. The noise margin of ZHP-TFET based resistive inverter comes 0.75 V, 0.73 V, and 0.77 V, while in case of HS-TFET these value noted as 0.32 V, 0.13 V and 0.37 V under consideration for no trap, acceptor trap, and donor trap, respectively.
The research of vasoconstriction effect on the solitary waves in stenotic arterial vessel
Authors: Sang Xue , Zhang Zongguo , Yang Hong-Wei , Fu Lei
Published: March 2023

Vascular stenosis is a common cardiovascular disease, and the in-depth study of its biomechanical mechanism will help to explore the occurrence mechanism and law of the disease, which is of great significance in the prevention and diagnosis of cardiovascular disease. Different from previous studies, radial and axial motions are considered in the realistic configuration of the wall, and the wall equation of the stenotic artery is established. On the basis of the wall equation and fluid equation, the KdV-Burgers equation is obtained by scale analysis and perturbation expansion. The effects of axial displacement and wall initial conditions on the propagation of solitary waves in stenotic arteries are discussed. It is shown that with the increase of the axial and radial tension ratios, the amplitude and width of the solitary wave increase, and the solitary wave becomes steeper and more sharp. The results of this study provide a theoretical value for detecting the shape change of solitary wave in blood vessel to predict vascular stenosis.
Surface stability and H adsorption and diffusion near surfaces of W borides: a first-principles study
Authors: Yang L. , Wirth B.D.
Published: March 2023

Understanding the behavior of tungsten boride (W
x
B
y
) surfaces in a fusion reactor environment is an important topic since boronization is a common wall conditioning method used in fusion Tokamaks. We report the results of density functional theory calculations that investigate the surface stability of W
x
B
y
(tetragonal I41/amd-WB, hexagonal P63/mmc-WB2 and tetragonal I4/m-W2B) with low-index orientations, as well as hydrogen (H) energetics near W
x
B
y
surfaces. For single element terminated W
x
B
y
surfaces, B terminated surfaces are more energetically stable than W terminated as a result of significant reconstruction of B. The H surface adsorption energy and activation energy of H diffusion penetration below W
x
B
y
surfaces are mainly related to the outer termination. Specifically, the WB(001) surface terminated with two B layers, referred to as WB(001)-TBB, has higher H adsorption affinity and lower H diffusivity on this surface than other terminations, which is controlled by the significant charge transfer from B to H. However, B atoms on the WB2(0001)-TBB surface decrease both H adsorption and diffusivity on the surface, but enhance H diffusion below the surface in comparison to W terminated WB2(0001) surface. H would be trapped and diffuse within atomic surface gaps on the WB2(

2

1
ˉ

1
ˉ

0

) surface, while H below the surface layer would jump along the [0001] direction rather than diffuse into bulk. The surface diffusion activation energy of H on the W2B(001) surface slightly varies with terminations. Once H crosses the surface layer of W2B(001) with either termination, it prefers to diffuse into the bulk, or back towards the surface, rather than move parallel to the surface. Interestingly, WB2(0001) and WB2(

2

1
ˉ

1
ˉ

0

) surfaces will have relatively higher H retention than the other W
x
B
y
surfaces evaluated in this work.
Penrose-like tilings from projection of affine A
4 to affine H
2
Authors: Koca Nazife O
Published: March 2023

The present work offers a different perspective for the 5-fold symmetric quasicrystallography by employing affine H
2 as a subgroup of affine A
4. It is shown that the projection of the Voronoi cell of the root lattice A
4 can be dissociated as identical five decagons up to a rotation tiled by thick and thin rhombuses. Projection of the Voronoi cell of the weight lattice onto the Coxeter plane tessellates the plane with four different tiles: thick and thin rhombuses with different edge lengths and two types of hexagons. Structure of the local dihedral symmetry H
2 fixing a particular point on the Coxeter plane is determined.
Multimagnon-mediated Raman scattering in two-dimensional quasiperiodic Heisenberg antiferromagnets
Authors: Yamamoto Shoji , Ohara Jun
Published: March 2023

We demonstrate configuration-interaction and Green’s function approaches to the Shastry-Shraiman fourth-order magnetic Raman response of Heisenberg antiferromagnets on the two-dimensional C5v Penrose and C8v Ammann-Beenker lattices. Beyond the Loudon-Fleury second-order perturbation scheme, two more symmetry species A1 and A2 become Raman-active to break the depolarized Loudon-Fleury Raman response of E2 symmetry. The A1 and A2 modes are activated by dynamic ring exchange and chiral spin fluctuations, respectively, the former of which owes much to multimagnon scatterings in a complicated manner, while the latter of which owes much to aperiodic arrangements of different rhombuses.
First-principles study of the initial stage of Pentacene adsorption on the twofold surface of the Ag-In-Yb quasicrystal
Authors: Sato M. , Hiroto T. , Matsushita Y. , Nozawa K.
Published: March 2023

The adsorption of the pentacene (Pn) molecule on the twofold surface of icosahedral (i)-Ag-In-Yb Quasicrystal (QC) have been studied by means of density functional theory (DFT) calculations. We calculate the adsorption energy of Pn at various positions with the molecular axis parallel to the surface and aligned along the fivefold or twofold symmetry axes directions. Pn is stabilised on a Yb trapezoid site from the acute rhombohedron units located between the rhombic triacontahedral clusters. The calculated adsorption energies for different molecular orientations can explain a recent experimental observation.
A new concept for carbon dioxide elimination from combustion plants flue gases
Authors: Panayotov V T , Panayotova M I
Published: March 2023

The production of energy from thermal power plants by burning fossil fuels is expected to remain a major part of the global energy mix for a significant period of time. The issue of pollutant emissions remains on the agenda, especially carbon dioxide (CO2) due to its large quantities released. The article proposes a new concept for the elimination of carbon dioxide and other gaseous pollutants from the waste gases of combustion plants. Based on the assessment of the thermodynamic feasibility of the processes, metals and alloys were selected and initial tests were performed for the transformation of model waste gases from thermal power plants into solid products that could be further utilized by hydrometallurgical technologies. Removals achieved at small scale laboratory experiments were >89 % CO2, > 71 % CO, > 96 % NOx and > 60 % SO2.
Development of the environmental market in Ukraine in the strategic perspective
Authors: Skorokhod I , Rodchenko V , Karlova O , Horbach L , Skorokhod D
Published: March 2023

The article reveals the features of organizational and economic support for the development of the environmental market in Ukraine. It shows the analysis of development of the environmentally friendly products market and services in Ukraine. Here we built a multiple-regression model of organic consumption in Ukraine, and the analysis is based on the following factors: the number of certified producers of organic products; the volume of consumption of organic products on the domestic market; the area of agricultural land allocated for organic production and the capacity of the organic market in Ukraine. It is proved that in order to intensify the organizational and economic support of the environmental market in Ukraine, it is necessary to determine the main socio-ecological and economic tools for creating a system of environmental goods production, including the adoption of new legislation; the implementation of the Ukraine-EU Association Agreement; informatization of the economy, formation of online services; the dissemination of environmental audit activities; the environmental insurance services in the agro-industrial complex; the digitalization of production cycles from production, logistics to preservation of quality and terms of realization and delivery of ecological production. We offered a number of strategic directions for ecological market development in Ukraine.
Approaches for assessing the public administration activities in the field of ensuring sustainability
Authors: Strelcow W , Padafet Iu , Ulyanchenko Yu
Published: March 2023

Paper has tried to find a balance between the traditional role of public administration (transparency, efficiency, information symmetry and other values of common European administrative space) and the new role since the European Green Deal (2020) and public procurement reform (2014) as a policy tool for promoting green growth. It has been argued that Green Public Governance Efficiency can be assessed according to inputs and outputs. The information can be organised into several categories: Investment in Environmental governance, public institution energy consumption and green public procurement. Some variables can be waged as outputs: sustainable development growth index (SDGI), consumer engagement in green governance and the achievement of Green Public Procurement (GPP) criteria. It is difficult to arrive at conclusions about a need for appropriate instrumental variables. Despite the limitations, these are valuable in light of how Public Administration can contribute to environmental protection and long-term growth.
Determination of the competitiveness of cities and districts of the Odessa region
Authors: Azhaman I , Petryshchenko N , Oklander T , Pandas A
Published: March 2023

The development of regions, their features and the possibility of a balanced growth of the economy of the regions are relevant for all countries. The ability to evenly and steadily develop the region and use the available resources is the basis of any management strategy. The choice of management model in the development of the region is influenced by a number of factors, among which are the limited resources, the level of development of the region and its general condition, scientific and technological progress, labor resources, transport links and other factors. The purpose of the study is to identify the most progressive and promising for investment areas of the Odessa region and depressive ones, which will allow implementing the region’s development strategy more efficiently and taking into account the needs of depressed regions.
Formulating silver nanoparticles from Syzygium Samagense flower buds extract
Authors: Nguyen Trong Q , Doan Trinh N D , Hong Quy L , Do Tri M , Nguyen Nguyen H
Published: March 2023

The study was to investigate the possibility of synthesizing silver nanoparticles by chemical reduction method using Syzygium Samagense flower bud extract as a green reducing agent. Various reaction conditions affecting the synthesis of silver nanoparticles were investigated including AgNO3 concentration (2 mM; 5 mM; 10 mM), volume ratio Vextract/VAgNO3 (2:30; 3:30; 4:30; 5:30), reaction temperature (50 – 80 °C), reaction time (15 - 60 mins). The presence of silver nanoparticles was detected by the combination of spectroscopy and X-ray diffraction (XRD) technology while the size of silver nanoparticles was determined by scanning electron microscopy (FE-SEM). The results showed that silver nanoparticles (owning an average size in the range of 20 - 35 nm) were successfully formulated with the highest yield when mixing the flower bud extract and AgNO3 solution (5 mM) with a ratio of 4:30 at 70 °C for 45 mins.
Nematode Community as a Tool to Monitor Ecosystem Health of Kembangkuning Mangrove Forest, Indonesia
Authors: Maharning A R , Ardli E R , Prabowo R E
Published: March 2023

Previous studies show that nematode community structure is an efficient bio-tool to detect environmental changes and pollution impacts. Despite their presence and function in an ecosystem, the nematode community is never used to monitor the Kembangkuning mangrove, Segara Anakan. Thus, we intended to collect nematode functional trait data as a baseline to monitor the mangrove ecosystem health. The mangrove is a naturally growing forest dominated by Rhizophora apiculata and Aegiceras corniculatum, surrounded by settlements and industries. We extracted nematodes from mangrove sediment using the Baermann funnel method. The nematode functional traits were recorded as the baseline data for monitoring purposes. To further examine the nematode community variations, we correlated the nematode functional traits and composition to specific environmental variables. Canonical correspondence analysis revealed a 25.32% accumulated variance with four prominent variables associated with the trait distribution (potassium r = 0.56, water content r = -0.56, salinity r = 0.75, organic carbon r = 0.68). Comparison with published data indicates that the three most abundant nematodes, the non-selective deposit and epistrate feeders of our study site, are also observed in anthropogenically disturbed areas. This finding suggests that our study site requires continual health monitoring to maintain a relatively healthy forest ecosystem.
Microencapsulation of agarwood (Aquilaria crassna) essential oil by spray drying
Authors: Thao Vy Truong , Truong Vinh
Published: March 2023

Agarwood essential oil is the essential oil extracted from the heartwood of agarwood trees (Aquilaria sp.) after inoculation or natural infection of one of several fungal species. The essential oil is proved to carry antioxidant, antimicrobial and anti-stress activities. Microencapsulation of essential oil included emulsification of oil into maltodextrin solution and spray drying of emulsion at different levels of inlet temperature and compressed air pressure. Microencapsulation process was qualified based on following parameters including process’s microencapsulation yield, moisture content of powder, powder particle size, encapsulated oil’s composition, oil recovery and drying yield. Microencapsulation yield was affected by inlet temperature whereas drying yield changed as air pressure varied from 1.5 to 2.5 kgf/cm2. Other parameters were impacted by both variables. Besides, oil composition changed at an acceptable degree after microencapsulation process, in which there were an increase in percentage and the presence of some components but the main components still remained in the encapsulated oil. Finally, the drying air temperature of 150 °C and air pressure of 2.5 kgf/cm2 were the best parameters to obtain both microencapsulation yield of 89.12% and drying yield of 79.00%.
Structural, optical properties and photocatalytic activity of spin-coated CuO thin films
Authors: Komaraiah Durgam , Sayanna Rodda
Published: March 2023

The semiconductor metal oxide CuO films have been fabricated using spin coating techniques. The prepared CuO thin films were annealed at different temperatures and characterized by an x-ray diffractometer, scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDS), FTIR, UV–vis, and fluorescence spectrometer. X-Ray diffraction (XRD) patterns revealed the polycrystalline nature of CuO with the monoclinic crystal structure. SEM analysis of CuO films endorsed the particle-like spherical shape structure. The CuO thin films have shown high optical absorption with a narrow bandgap. The band gap values were evaluated from Tauc’s plots and these values were found to be in the range of 1.63 to 1.72 eV. At an excitation of 325 nm, the CuO films display characteristic photoluminescence (PL) emission in the UV and visible regions. Furthermore, the CuO thin films show enhanced photocatalytic performance towards the degradation of organic dyes under visible light.
Dual emission and its λ-ratiometric detection in analytical fluorimetry Pt. II. Exploration in sensing and imaging
Authors: Demchenko Alexander P
Published: March 2023

The wavelength-ratiometric techniques demonstrate strong advantages in fluorescence sensing and imaging over techniques employing variations of intensity at single wavelength. We present different possibilities for realization of these advantages in different simplified, miniaturized and multiplexing devices. They include the smartphone-based detection systems and strips, in which the color changes are observed with naked eye. The array-based techniques and different immunoassays with λ-ratiometric detection demonstrate strongly increased stability and sensitivity. The application areas extend from on-site monitoring of environment and point-of-care diagnostics to testing in personal need. Selected examples of sensing different analytes in chemical and biological systems demonstrate multiple possibilities of coupling the analyte-sensor interaction with the generation of λ-ratiometric output signal. Among them, simultaneous detection of several analytes and performing logical operations that can be useful in analysis. Finally, the benefits of multicolor ratiometric fluorescence imaging are demonstrated by visualization the functionally important parameters of biological membranes.