bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tuning the thermal conductivity of silicon nanowires by surface passivation
Authors: Ruscher Céline , Cortes-Huerto Robinson , Hannebauer Robert , Mukherji Debashish , Nojeh Alireza , Srikantha Phani A 
Published: August 2024

Abstract
Using large scale molecular dynamics simulations, we study the thermal conductivity of bare and surface passivated silicon nanowires (SiNWs). For the cross–sectional widths

w
⩽
2

nm, SiNWs become unstable because of the surface amorphization and also due to the evaporation of a certain fraction of Si atoms. The observed surface (in–)stability is related to a large excess energy Δ of the surface Si atoms with respect to the bulk Si, resulting from the surface atoms being less coordinated and having dangling bonds. We first propose a practically relevant method that uses Δ as a guiding tool to passivate these dangling bonds with hydrogen or oxygen, stabilizing the SiNWs. These passivated SiNWs are used to calculate the thermal conductivity coefficient κ. While the expected trend of

κ
∝
w

is observed for all SiNWs, surface passivation provides an added flexibility of tuning κ with the surface coverage concentration c of passivated atoms. Indeed, with respect to the bulk κ, passivation of SiNW reduces κ by 75%–80% for

c
→
50
%

and increases it by 50% for the fully passivated samples. Analyzing the phonon band structures via spectral energy density, we discuss separate contributions from the surface and the core to κ. Our results also reveal that surface passivation increases SiNW stiffness, contributing to the tunability in κ.
Evaluation of plasma process-induced mechanical property change in SiN films using a cyclic nanoindentation technique
Authors: Goya Takahiro , Urabe Keiichiro , Eriguchi Koji 
Published: August 2024

Abstract
Recently, plasma process-induced damage (PID) has garnered significant interest in the design of thin dielectric films implemented in semiconductor devices. Silicon nitride (SiN) films, a material of interest in strain engineering, are found to suffer from PID because they are exposed to various plasmas during device manufacturing processes. Only a limited amount of experimental evidence is available at present regarding plasma-induced mechanical property changes of SiN films. In this study, we investigated the mechanical property change in SiN and SiO2 films using a cyclic nanoindentation technique. We focused on the contact stiffness (S) as the principal mechanical property parameter. Firstly, a single loading/unloading test confirmed an increase in S after Ar and He plasma exposures. Subsequently, we examined the time-dependent features of damaged SiN and SiO2 films under cyclic loading/unloading. From the cyclic test, an increase in S was seen with the number of loading/unloading cycles (N) for both SiN and SiO2 films. A larger increase in S was observed for the damaged SiN, while no significant increase was seen for the damaged SiO2 films. The observed increase in S and its time dependence are attributed to the strain developed by the created defects (e.g. interstitial species) and the reconstruction and stabilization of plasma-damaged Si–N networks with created defects, respectively. The time-dependent S analysis under cyclic loading/unloading is useful for evaluating the effects of PID on the mechanical properties of thin films.
Reversed self-steepening in Si3N4-organic hybrid slot waveguides with engineered nonlinearity
Authors: Zhai Yuke , Xu Lijuan , Ren Kexin , Zhang Lin 
Published: August 2024

Abstract
Dispersion of nonlinearity greatly influences both temporal and spectral evolutions for ultrashort pulses, although difficult to be tailored in a wide spectral range. Here, we show the hardly observable reversed self-steepening in an on-chip Si3N4-organic hybrid slot waveguide with sophisticated dispersion and an increased nonlinear coefficient with wavelength. An octave-spanning supercontinuum with significant red-shift spectral broadening and a rectangle-shaped pulse waveform with a sharp rising edge of 13 fs can be generated. We study the robustness of reversed self-steepening under different operating conditions and reveal its nonlinear dynamics. This deepens the understanding on the dispersion of nonlinearity and helps develop novel nonlinearity-engineered devices for on-chip optical shock formation, pulse shaping, and signal processing in the future.
EM optimization of microwave filter based on long short-term memory–feedforward neural network and transfer functions
Authors: Zhang Xin , Wu Jian , Chai Yong-Qiang , Liu Shui , Peng Yuan 
Published: August 2024

Abstract
An electromagnetic optimization technique based on a long short-term memory–feedforward neural network (LSTM-FNN) and transfer functions is proposed for microwave filter design. The proposed optimization method addresses the situation where a neuro-transfer function model repeatedly trains at each optimization iteration process. The proposed surrogate model combines the LSTM-FNN and polynomial model to map nonlinear relationships between geometric variables and transfer functions. Firstly, by combining the gate mechanism of LSTM with the high generalization ability of an FNN, the proposed LSTM-FNN effectively learns nonlinear relationships between geometric variables and frequency responses at specific frequencies. Secondly, the transfer functions can be accurately approximated via polynomial fitting. Frequency responses at any interesting frequency range can be accurately expressed using the transfer functions. Finally, the trained surrogate model, exploiting the trust-region algorithm, can accurately and efficiently achieve optimization convergence. An example of a low-pass filter (LPF) is adopted to validate the proposed optimization method.
Light-induced fading effects on TL and OSL signals and feasibility of dose re-assessment with PTTL signals in BeO dosimeters
Authors: Aşlar Engin 
Published: August 2024

Abstract
This study aims to investigate both light-induced fading effects on thermoluminescence (TL) and optically stimulated luminescence (OSL) signals under three different light sources (fluorescent, UV-254 and daylight) and dose reassessment with phototransferred TL (PTTL) signals in Beryllium oxide dosimeters. TL and OSL signals were deconvoluted for each light source. Accordingly, variations in the maximum peak temperature, activation energy, peak area value for the TL signal, and intensity and lifetime values for the OSL signal were monitored. Each peak, OSL component, and total area value exhibited different behaviors depending on the light source. Considering the total area condition, the TL intensity decreased by ∼90%, ∼80%, and ∼70% in UV-254, daylight, and fluorescent light exposure, respectively, at the end of the 120 min. On the other hand, the OSL total area intensity faded quickly for both UV-254 and daylight, while it decreased by ∼45% for fluorescent light. According to these results, regardless of TL and OSL measurements, the dosimeters should be kept primarily away from daylight and fluorescent light after irradiation, instead of UV-254, which is rarely encountered in daily life. The feasibility of dose reassessment using PTTL signals under UV-254 light was investigated within a wide dose range from 0.1 to 128 Gy. It is feasible to reassess doses between 0.5 and 32 Gy considering the total area intensity of PTTL signals. In conclusion, PTTL signals can be easily used in fields of the order of Gy, such as in reevaluating doses in radiotherapy applications.
Flavor identification based on olfactory-taste synesthesia model and hybrid convolutional neural network-random forest
Authors: Zheng Wenbo , Pan Guangyuan , Zhu Fengzeng , Zhang Ancai 
Published: August 2024

Abstract
The bionic-based electronic nose (e-nose) and electronic tongue (e-tongue) show satisfactory performance in flavor analysis. Traditional flavor analysis of the e-nose and e-tongue systems focuses on data fusion, and the effects of the bionic characteristics on the flavor analysis performance are rarely studied. Motivated by this, a method, including an olfactory-taste synesthesia model (OTSM) and a convolutional neural network-random forest (CNN-RF), is proposed for the effective identification of flavor substances. The OTSM is developed for human nerve conduction mechanisms to enhance the bionic characteristics of the e-nose and e-tongue systems and is combined with a CNN-RF model for flavor identification. The results show that, first, when stimulated by e-nose and e-tongue data, physiological 1/f characteristics and synchronization are shown using the OTSM. The enhancement effects on the bionic characteristics of the fusion system are validated using the 1/f characteristics and synchronization. Second, the fully connected layer for the CNN is replaced by RF to improve the identification performance of flavor substances. Finally, CNN-RF is evaluated in comparison with other flavor recognition models and ablation studies to confirm its effectiveness. By comparison, the best recognition performance, including the accuracies of 96.67%, 96.67%, and 95.00%, the F1-scores of 96.65%, 96.66%, and 94.95%, and the kappa coefficients of 96.03%, 96.10%, and 93.44%, for five beers, five apples, and four mixed solutions, respectively, is obtained by CNN-RF. In conclusion, excellent flavor identification for the fusion system is achieved using the OTSM and CNN-RF models.
DFT analysis of Re-modified WSe2 monolayers for adsorption of CO, C2H2, and C2H4
Authors: Sarkar Suman , Debnath Papiya , De Debashis , Chanda Manash 
Published: August 2024

Abstract
The sensing performances of the Rhenium (Re) doped Tungsten Diselenide (WSe2) monolayer for detecting small gas molecules such as carbon monoxide (CO), acetylene (C2H2), and ethylene (C2H4) have been analyzed in this paper. Density functional theory and non-equilibrium Green’s function have been used to examine the electrical and geometric structures of re-adorned WSe2 monolayer when subjected to dissolved gas analysis gases in the transformer oil. Hence, the electrochemical characteristics like Band diagram and density of states are detailed. Adsorption systems’ recovery capabilities, Mulliken population, and adsorption energy have been examined to determine their stability. Studies also show that Re-doped WSe2 monolayer exerts deformation and as a result, the band gap narrowed down. At ambient temperature (273 K–300 K), the Re-doped WSe2 exhibits better adsorption of C2H4 over C2H2 and CO as the C2H4 has higher adsorption energy compared to the C2H2 and CO. Besides, V–I characteristics of the Re doped WSe2 layer after adsorption of the CO, C2H2, and C2H4 are detailed which signifies the efficacy of the Re doped WSe2 monolayer.
A coupled crystal inelasticity-phase field model for crack growth in polycrystalline nitinol microstructures
Authors: Maloth Thirupathi , Appel Pheobe , Erlebacher Jonah , Ghosh Somnath 
Published: August 2024

Abstract
This paper introduces a comprehensive computational framework, comprising a finite deformation crystal inelasticity constitutive model and phase field model, for modeling crack growth in superelastic nitinol polycrystalline microstructures. The crystal inelasticity model represents crystal stretching and lattice rotation from elastic mechanisms, as well as local inelastic deformation due to austenite-martensite phase transformation. The phase field formulation decomposes the Helmholtz free energy density into stored elastic energy, phase transformation energy, and crack surface energy components. The elastic energy accounts for tension-compression asymmetry with the formation of the crack through a spectral decomposition. Kinetic Monte Carlo simulations generate equilibrium area fractions of different surface orientations, which serve as weights for the surface energy. An adaptive wavelet-enhanced hierarchical finite element (FE) model is introduced to alleviate high computational overhead in phase field crack simulations. Simulations with the coupled inelasticity phase field model are conducted under various loading conditions including Mode-I tension, a quasi-static Kalthoff experiment, and cyclic loading of polycrystalline microstructures. Crack propagation is effectively predicted by this model, providing valuable insights into the material mechanical behavior with growing cracks.
Tensile strength prediction of steel sheets: an insight into data-driven models, dimensionality reduction, and feature importance
Authors: Millner Gerfried , Mücke Manfred , Romaner Lorenz , Scheiber Daniel 
Published: August 2024

Abstract
In this work we apply data-driven models for predicting tensile strength of steel coils from chemical composition and process parameters. The data originates from steel production and includes a full chemical analysis, as well as many process parameters and the resulting strength properties from tensile tests. We establish a data pre-processing pipeline, where we apply data cleaning and feature engineering to create a machine-readable dataset suitable for various modeling tasks. We compare prediction quality, complexity and interpretability of pure machine learning (ML) models, either with the full feature set or a reduced one. Dimensionality reduction methods are used to reduce the number of features and therefore reduce complexity, either with a smart selection method or feature encoding, where features are combined and the included information is preserved. In order to determine key features of our models, we are investigating feature importance ratings, which can be used as a feature selection criteria. Furthermore, we are highlighting methods to explain predictions and determine the impact of every feature in every observation applicable for any ML model.
Dark-field microscopy studies of single silicon nanoparticles fabricated by e-beam evaporation technique: effect of thermal annealing, polarization of light and deposition parameters
Authors: Sahoo Sibanisankar , Naik Aadesh M , Laha Ranjit , Dantham Venkata R 
Published: August 2024

Abstract
Herein, we report the dark-field microscopy studies on single silicon nanoparticles (SiNPs) fabricated using different deposition parameters in the electron beam evaporation technique. The morphology of the fabricated SiNPs is studied using the Atomic Force Microscope. Later, for the first time, the effect of thermal annealing and deposition parameters (i.e. beam current and deposition time) on the far-field scattering images and spectra of single SiNPs is studied using a transmission-mode dark-field optical microscope to estimate the wavelength locations and full-width at half maxima of the optical resonances of single SiNPs. Finally, the role of polarization of incident light on the optical resonances of single SiNPs is also studied by recording their scattering images and spectra.
Nanoengineered pure Fe in a citrate matrix (Fe–CIT) with significant and tunable magnetic properties
Authors: Getahun Yohannes , Das Debabrata , Ramana C V , El-Gendy Ahmed A 
Published: August 2024

Abstract
This work demonstrates the synthesis and characterization of Fe nanoparticles surrounded by a citrate (CIT) matrix prepared at various temperatures and concentrations of metal, capping agent and reducing agent at standard conditions. We study the effect of reactant ratio and reaction temperature on the magnetization of the produced nanoparticles and their crystal structure. We found that for optimal metal concentrations, magnetic saturation increases with increase in the concentration of capping and reducing agents but decreases as the temperature of the reaction increases. Synthesis conditions were tailored to reveal nucleation of particles with average sizes ranging from 24 to 105 nm and a spherical shape. The ultra-high saturation magnetization of 228 emu g−1 obtained for samples prepared at a metal precursor concentration of 27.8 mol l−1 was attributed to the formation of small magnetic domains. Energy band gap measurements revealed a band gap energy for the Fe nanoparticles in the CIT matrix which is associated with CIT concentration and/or possible formation of a few thin layers of iron oxide shell and does not have a significant effect on the magnetic properties of the samples. Herein, we demonstrate that the synthesis parameters are crucial for the nucleation of Fe-CIT nanoparticles tailoring their magnetizatic properties as well as their potential for different applications.
Nucleic acid-functionalized gold nanoparticles as intelligent photothermal therapy agents for precise cancer treatment
Authors: Tang Hongmei , Zhang Xuetao , Bao Yuyan , Shen Huazhen , Fan Minglan , Wang Yangchen , Xiang Siyun , Ran Xiang 
Published: August 2024

Abstract
We present an intelligent photothermal therapy agents by functionalizing gold nanoparticles with specific nucleic acid sequences. Hairpin nucleic acids are modified to the nanoparticles, forming AuNPs-1 and AuNPs-2. Upon infiltrating cancer cells, these nanoparticles undergo catalytic hairpin assembly in the presence of target miRNA, leading to aggregation and subsequent photothermal conversion. Under near-infrared laser irradiation, aggregated gold nanoparticles exhibit efficient photothermal conversion, selectively damaging cancer cells. This approach offers heightened selectivity, as nanoparticles only aggregate in environments with cancer biomarkers present, sparing normal cells. Cytotoxicity assays confirm minimal toxicity to normal cells. In vivo studies on mice bearing solid tumors validate the system’s efficacy in tumor regression. Overall, this study highlights the potential of nucleic acid-functionalized gold nanoparticles in intelligent and selective cancer photothermal therapy, offering insights for targeted diagnosis and treatment development.
Construction of CDs@β-CD@CCM ratiometric fluorescence probe for FRET-based ClO–-sensing
Authors: Xu Ruoqian , Hu Zhongfei , Dong Xuemei , Xiao Xuan , Ding Yujie 
Published: August 2024

Abstract
β-Cyclodextrin (β-CD)—functionalized carbon quantum dots (CDs) loaded with curcumin (CCM) were used for ClO– sensing with high sensitivity and selectivity. This fluorescence resonance energy transfer (FRET)-based sensor was created through attaching CCM to the CDs via β-CD linker. CCM could get into the interior of β-CD triggering the FRET from CDs to CCM, providing an ‘off’ state of the CDs. However, the effect of FRET was weakened by the ClO–, because the o-methoxyphenol structure from CCM was oxidized to be benzoquinone. The fluorescence intensity of CDs@β-CD@CCM at 440 nm can be heightened and 520 nm from CCM can decrease along with the increased ClO–. Therefore, a ratiometric fluorescence probe for ClO– sensing is successfully constructed. It conforms to a polynomial curve equation which is I440/I520 = −0.0268 + 0.0315 CClO
–+ 0.0055[CClO
–]2 (R
2 = 0.9958) between 0 and 18.4 μM ClO–. Furthermore, we also obtain excellent results using this spectrophotometric method for ClO–-sensing in pure water and commercial disinfectants, which afford potential in the environment monitoring area. We expect this sensing platform could be helpful in other analogous probes in relevant fields.
Scatter estimation and correction using time-of-flight and deconvolution in x-ray medical imaging
Authors: Rossignol Julien , Bélanger Gabriel , Fromont Maëlle , C Therrien Audrey , Fontaine Réjean , Bérubé-Lauzière Yves 
Published: August 2024

Abstract

Objective. Time-of-flight (TOF) scatter rejection requires a total timing jitter, including the detector timing jitter and the x-ray source’s pulses width, of 50 ps or less to mitigate most of the effects of scattered photons in radiography and CT imaging. However, since the total contribution of the source and detector to the timing jitter can be retrieved during an acquisition with nothing between the source and detector, it can be demonstrated that this contribution may be partially removed to improve the image quality. Approach. A scatter correction method using iterative deconvolution of the measured time point-spread function estimates the number of scattered photons detected in each pixel. To evaluate the quality of the estimation, GATE was used to simulate the radiography of a water cylinder with bone inserts, and a head and torso in a system with total timing jitters from 100 ps up to 500 ps full-width-at-half-maximum (FWHM). Main results. With a total timing jitter of 200 ps FWHM, 89% of the contrast degradation caused by scattered photons was recovered in a head and torso radiography, compared to 28% with a simple time threshold method. Corrected images using the estimation have a percent root-mean square error between 2% and 14% in both phantoms with timing jitters from 100 to 500 ps FWHM which is lower than the error achieved with scatter rejection alone at 100 ps FWHM. Significance. TOF x-ray imaging has the potential to mitigate the effects of the scattering contribution and offers an alternative to anti-scatter grids that avoids loss of primary photons. Compare to simple TOF scatter rejection using only a threshold, the deconvolution estimation approach has lower requirements on both the source and detector. These requirements are now within reach of state-of-the-art systems.
Gain enhancement of mm-wave antenna using graded index lens integrated frequency selective surface for 5G NR FR2 applications
Authors: Babu K Vasu , Sree Gorre Naga Jyothi , Das Sudipta , Ali Wael , Altameem Torki , El-Shafai Walid 
Published: August 2024

Abstract
In this study, the gain of a printed antenna is boosted for utilization in 5G systems by employing a phase-oriented graded index-type lens system. In the prescribed design, various metamaterial unit cells are arranged as arrays with radial phases for the graded meta lens to optimize transmission characteristics. The suggested arrangement creates a meta lens with spatially varying surface impedance and locally varying refractive index, allowing the conversion of spherical wavefronts into planar wavefronts for beam collimation in the 5G band. The focal length-to-diameter ratio (f/d) is fixed at 0.38 in this prescribed design. The integration of the FSS structure with the patch antenna enhances the efficiency above 98% and increases gain by 2.635dBi owing to the focusing effect of the properly placed lens. The prescribed planar lens is easy to realize during manufacturing compared to 3D lenses. The meta lens integrated patch yields a gain of around 8.936dBi at 29 GHz. The performance of the lens antenna is evaluated through simulation studies and then validation of results is performed with experimental arrangement to ensure accuracy and reliability of the suggested methodology for gain enhancement of the functioning antenna at FR2 5G spectrum.
Lattice stick number 15 is unattainable for non-splittable links
Authors: Huh Youngsik , No Sungjong , Oh Seungsang 
Published: August 2024

Abstract
In this paper, we explore mathematical links, defined as closed curves embedded in 3D space. Knot theory studies these structures, which also occur in real-world biopolymers like DNA. Lattice links are links in the cubic lattice. For scientific simulations or statistical studies, links are simplified to lattice links. The lattice stick number, denoted as s

L
(K), is the minimum number of lattice sticks needed to represent a link K in the cubic lattice. In previous study, it was shown that only two non-trivial knots and six non-splittable links have s

L
≤ 14: specifically,

s

L

(

2

1

2

)
=
8

,

s

L

(

3

1

)
=

s

L

(

2

1

2

♯

2

1

2

)

=

s

L

(

6

2

3

)

=

s

L

(

6

3

3

)
=
12

,

s

L

(

4

1

2

)
=
13

, and

s

L

(

4

1

)
=

s

L

(

5

1

2

)
=
14

. Recent study has further revealed that no knot can have s

L
= 15. In this paper, we prove that lattice stick number 15 is not attainable for non-splittable links. As a corollary, eleven non-splittable links with s

L
=16 are presented.