bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct growth of highly oriented GaN thin films on silicon by remote plasma CVD
Authors: Watrin Lise , Silva François , Jadaud Cyril , Bulkin Pavel , Vanel Jean-Charles , Muller Dominique , Johnson Erik V , Ouaras Karim , Roca I Cabarrocas Pere 
Published: April 2024

Abstract
We report on low-temperature (500 °C) and low-pressure (0.3 mbar) direct growth of GaN thin films on silicon (100) substrates using remote plasma chemical vapour deposition (RP-CVD). In the custom-designed reactor, an RF inductively coupled plasma is generated remotely from the substrate’s area to facilitate the decomposition of group-V precursor, N2 with added H2, while group-III precursor trimethylgallium (TMGa), is directly injected into the growth chamber mixed with H2 carrier gas. Growth parameters such as RF power, process pressure and gas flow rates have been optimized to achieve a film growth rate of about 0.6 µm h−1. Several characterization techniques were used to investigate the plasma and the properties of the grown thin films in terms of their crystallinity, morphology, topography, and composition. The films are highly textured with a preferential orientation along the c-axis of the wurtzite structure. They present a small roughness in the nanometer range and a columnar microstructure with a grain size of one hundred nanometer, and a gallium polarity (+c plane oriented). Rutherford backscattering spectrometry and nuclear reaction analysis show that the chemical composition is homogeneous through the depth of the layer, with a III/V ratio close to 1, a very low content of oxygen (below the detection limit ∼1%) and a carbon content up to 11%. It was shown that the increase of plasma power helps to reduce this carbon contamination down to 8%. This research paves the way for a growth method compatible with cost reduction of III–V thin film production achieved through reduced gas consumption facilitated by RP-CVD operation at low pressure.
Stimuli-responsive photoluminescent and structural properties of MIL-53(Al) MOF for sensing applications
Authors: Rehman T Ul , Agnello S , Gelardi F M , Calvino M M , Buscarino G , Cannas M 
Published: April 2024

Abstract
Metal–organic frameworks (MOFs) are an intriguing group of porous materials due to their potential influence on the development of indispensable technologies like luminescent sensors and solid-state light devices, luminescent multifunctional nanomaterials. In this research work we explored MIL-53(Al), an exceptional class of MOF that, along with guest adsorption, undergoes structural transitions exhibiting breathing behavior between narrow pore and large pore under temperature and mechanical stress. Therefore, we opted for the time resolved luminescence and FT-Raman spectroscopy to investigate the mechanochromic and thermochromic response of this material under external stimuli. Intriguingly, when subjected to temperature changes, MIL-53(Al) exhibited a ratiometric fluorescence behavior related to the reversible relationship of photoluminescence emission intensity with respect to temperature. Moreover, under higher mechanical stress MIL-53(Al) displayed turn-on behavior in emission intensity, hence offering a thrilling avenue for the application in mechanically deformed-based luminescent sensors and ratiometric fluorescence temperature sensors.
Precise refractive index measurement of fused silica optics
Authors: Jagroop  , Tillo Dakshin , Narayanamurthy C S , Sam Dayala Dev D 
Published: April 2024

Abstract
We have developed an experimental platform that non-destructively and precisely measures the Refractive Index (RI) and dispersion of ultra-polished fused silica optics. Using Total Internal Reflection Digital Holographic Microscopy (TIRDHM), we exploit the phase change of reflected light in Total Internal Reflection (TIR) mode. This phase change depends on the incident angle at the TIR interface and the refractive indices of the involved media. We have optimized a combination of higher TIR phase sensitivity, considerable penetration depth, and minimized phase measurement inaccuracies through simulations to design our experiment. Key features include a custom-made precision Right-Angle Prism (RAP) of Astrositall material, a seamless interface with fused silica optics on TIR interface through optical contact, and single-shot measurement. We have demonstrated the accuracy of measuring fused silica optics through proof of concept and experimental results. Our measurements on two different samples show accuracy better than ±3 × 10−4 compared to those obtained using a commercially available critical angle Refractometer (Metricon). Importantly, the setup offers the advantage of spatially mapping the refractive index, unlike point measurements by available Refractometers.
Prediction of mechanical properties of LPBF built part based on process monitoring and Gaussian process regression
Authors: Yuan Zhenghui , Peng Xiaojun , Ma ChenGuang , Zhang Aoming , Chen Zhangdong , Jiang Zimeng , Zhang Yingjie 
Published: April 2024

Abstract
As a highly promising technology in additive manufacturing, the laser powder bed fusion has only limited application due to its low reproducibility. In this study, the image information of the 316L specimen after laser scanning and powder paving of each layer was acquired by a complementary metal–oxide–semiconductor industrial camera. The important features were selected, extracted and quantificated by analyzing the tensile test results. Finally, combined with the laser power, the quantified features were as input of a Gaussian process regression model based on optimization algorithm of grid search to predict the tensile strength of 316L specimen. The results show that the quantized image features have a significant improvement on the regression effect, and the coefficient of determination (R
2) is improved from 63% to 90.57% compared to using only the laser power as input.
Two-dimensional LSTM soft sensor using noisy process data
Authors: Liu Qiao , Jia Mingwei , Guo Xiaowei , Liu Yi , Gao Zengliang , Xu Liangfeng 
Published: April 2024

Abstract
Establishing a reliable data-based soft sensor still faces a series of challenges, particularly the presence of outliers and different kinds of noise which are non-negligible in process data. To address these challenges, a correntropy-based two-dimensional long short-term memory (TLSTM) model is developed to handle noisy process data. First, the multidimensional time series samples are reconstructed into numerous two-dimensional input matrices in the feature and time directions. Then, the convolution and pooling operations are used to extract useful information in the process variables related to the quality variable. Meanwhile, a gating mechanism is employed to learn the internal representation of time series. Finally, a correntropy-based strategy is utilized to assign relatively small weights to outliers automatically, enabling reliable prediction. Two cases illustrate the reliability and advantages of TLSTM in effectively extracting quality-related features for prediction.
OSLD nanoDot characterization for carbon radiotherapy dosimetry
Authors: Taylor Paige A , Hartzell Shannon , Mirandola Alfredo , Ciocca Mario , Magro Giuseppe , Alvarez Paola , Peterson Christine B , Peeler Christopher R , Koay Eugene J , Howell Rebecca M , Kry Stephen F 
Published: April 2024

Abstract

Objective. This study characterized optically-stimulated luminescent dosimeter (OSLD) nanoDots for use in a therapeutic carbon beam using the Imaging and Radiation Oncology Core (IROC) framework for remote output verification. Approach. The absorbed dose correction factors for OSLD (fading, linearity, beam quality, angularity, and depletion), as defined by AAPM TG 191, were characterized for carbon beams. For the various correction factors, the effect of linear energy transfer (LET) was examined by characterizing in both a low and high LET setting. Main results. Fading was not statistically different between reference photons and carbon, nor between low and high LET beams; thus, the standard IROC-defined exponential function could be used to characterize fading. Dose linearity was characterized with a linear fit; while low and high LET carbon linearity was different, these differences were small and could be rolled into the uncertainty budget if using a single linearity correction. A linear fit between beam quality and dose-averaged LET was determined. The OSLD response at various angles of incidence was not statistically different, thus a correction factor need not be applied. There was a difference in depletion between low and high LET irradiations in a primary carbon beam, but this difference was small over the standard five readings. The largest uncertainty associated with the use of OSLDs in carbon was because of the k
Q correction factor, with an uncertainty of 6.0%. The overall uncertainty budget was 6.3% for standard irradiation conditions. Significance. OSLD nanoDot response was characterized in a therapeutic carbon beam. The uncertainty was larger than for traditional photon applications. These findings enable the use of OSLDs for carbon absorbed dose measurements, but with less accuracy than conventional OSLD audit programs.
Effect of SiC nanoparticles on mechanical and damping properties of epoxy/polysulfide rubber blend composite
Authors: AlHumairee Salwan Hasan , Hunain Mustafa Baqir , Mahmood Ibtihal A 
Published: April 2024

Abstract
Blend polymer matrix composite material are becoming more and more popular due to their promising mechanical properties. In this research, blend polymer mixture was make from epoxy resin (EP) blended with different weight percentages of polysulfide rubber (PSR) (0, 3, 6, 10, 15, and 20%). Then tensile, impact, bending strength and damping ratio were evaluated to get the high quality of mechanical properties for the blend matrix. Due to the requirements to enhance the mechanical properties of this blend; a various weight fraction of carbide silica (SiC) nanoparticle was used as a reinforcement in the ratios of (0, 1, 3, and 5%) by weight to the best ratio of the blended matrix. Tensile, impact, bending and damping ratio tests were also conducted to get the best mechanical properties for the blend materials. Experimental results for the blend matrix showed that adding polysulfide rubber to epoxy resin resulted in a decrease in Young’s modulus, tensile strength, and bending strength; however damping ratio and the impact strength increased. It is found that the weight fraction of 6% of PSR is the Better case, which gave the better mechanical characteristics properties for mixture. Utility of this mixture; it has intermediates between flexible properties of a mixture at the highest rate of PSR and brittle mechanical properties for EP resin. Mechanical and damping properties showed an increasing when the carbide silica (SiC) with a weight fraction of 3% added, then it decreased slightly.
Amplifying the capacity of quantum super dense coding by non-Hermitian operations under phase decoherence source
Authors: Wang Qiong , He Zhi 
Published: April 2024

Abstract
We study the dynamic behavior of quantum super dense coding between two uncoupled qubits, which are immersed in a common Ohmic environment. We examine the validity of local non-Hermitian operations in the amplification of quantum super dense coding. In particular, using analytical and numerical investigations, we show explicitly that the capacity of quantum super dense coding can be greatly amplified with the assistance of a local non-Hermitian operation, i.e. a parity-time symmetric operation. This sheds new light on the protection of quantum super density.
p-wave resonances in the exponential cosine screened Coulomb potential*
Authors: Wang Yuan-Cheng , Jiao Li Guang , Liu Aihua , Ho Yew Kam , Fritzsche Stephan 
Published: April 2024

Abstract
We perform benchmark calculations of the p-wave resonances in the exponentially cosine screened Coulomb potential using the uniform complex-scaling generalized pseudo-spectral method. The present results show significant improvement in calculation accuracy compared to previous predictions and correct the misidentification of resonance electron configuration in previous works. It is found that the resonance states approximately follow an n
2-scaling law which is similar to the bound counterparts. The birth of a new resonance would distort the trajectory of an adjacent higher-lying resonance.
Influence of liquid film shape on evaporation performance of agitated thin film evaporator
Authors: Gu 顾 Xin-Qiang 鑫强 , Huang 黄 Yao 瑶 , Zou 邹 Kun 鲲 , Peng 彭 Yi-Tian 倚天 
Published: April 2024

Abstract
The agitated thin film evaporator (ATFE), which is known for its high efficiency, force the material to form a film through the scraping process of a scraper, followed by evaporation and purification. The complex shape of the liquid film inside the evaporator can significantly affect its evaporation capability. This work explores how change in shape of the liquid films affect the evaporation of the materials with non-Newtonian characteristics, achieved by changing the structure of the scraper. Examining the distribution of circumferential temperature, viscosity, and mass transfer of the flat liquid film shows that the film evaporates rapidly in shear-thinning region. Various wavy liquid films are developed by using shear-thinning theory, emphasizing the flow condition in the thinning area and the factors contributing to the exceptional evaporation capability. Further exploration is conducted on the spread patterns of the wavy liquid film and flat liquid film on the evaporation wall throughout the process. It is noted that breaking the wavy liquid film on the evaporating wall during evaporation is challenging due to its film-forming condition. For which the fundamental causes are demonstrated by acquiring the data regarding the flow rate and temperature of the liquid film. The definitive findings of the analysis reveal a significant improvement in the evaporation capability of the wavy liquid film. This enhancement is attributed to increasing the shear-thinning areas and maintaining the overall shape of the film throughout the entire evaporation process.
Light-emitting devices based on atomically thin MoSe2
Authors: Zhang Xinyu , Zhang Xuewen , Hu Hanwei , Zhang Vanessa Li , Xiao Weidong , Shi Guangchao , Qiao Jingyuan , Huang Nan , Yu Ting , Shang Jingzhi 
Published: April 2024

Abstract
Atomically thin MoSe2 layers, as a core member of the transition metal dichalcogenides (TMDs) family, benefit from their appealing properties, including tunable band gaps, high exciton binding energies, and giant oscillator strengths, thus providing an intriguing platform for optoelectronic applications of light-emitting diodes (LEDs), field-effect transistors (FETs), single-photon emitters (SPEs), and coherent light sources (CLSs). Moreover, these MoSe2 layers can realize strong excitonic emission in the near-infrared wavelengths, which can be combined with the silicon-based integration technologies and further encourage the development of the new generation technologies of on-chip optical interconnection, quantum computing, and quantum information processing. Herein, we overview the state-of-the-art applications of light-emitting devices based on two-dimensional MoSe2 layers. Firstly, we introduce recent developments in excitonic emission features from atomically thin MoSe2 and their dependences on typical physical fields. Next, we focus on the exciton-polaritons and plasmon-exciton polaritons in MoSe2 coupled to the diverse forms of optical microcavities. Then, we highlight the promising applications of LEDs, SPEs, and CLSs based on MoSe2 and their heterostructures. Finally, we summarize the challenges and opportunities for high-quality emission of MoSe2 and high-performance light-emitting devices.
Hybrid bonding of GaAs and Si wafers at low temperature by Ar plasma activation
Authors: Huang Rui , Wang Zhiyong , Wu Kai , Xu Hao , Wang Qing , Guo Yecai 
Published: April 2024

Abstract
High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology. The influence of Ar plasma activation on surface morphology is discussed. When the annealing temperature is 300 ℃, the bonding strength reaches a maximum of 6.2 MPa. In addition, a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different temperatures. The shape variation of the wafer is directly proportional to the annealing temperature. At an annealing temperature of 400 ℃, the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 mm. The interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron microscope. The characterization of interface elements by X-ray energy dispersion spectroscopy indicates that the elements at the interface undergo mutual diffusion, which is beneficial for improving the bonding strength of the interface. There is an amorphous transition layer with a thickness of about 5 nm at the bonding interface. The preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits, improve the performance of materials and devices, and promote the development of microelectronics technology.
Shoulder viscoelasticity in a raptor-inspired model alleviates instability and enhances passive gust rejection
Authors: Stanton Samuel C 
Published: April 2024

Abstract
Recent experiments with gliding raptors reveal a perplexing dichotomy: remarkably resilient gust rejection, but, at the same time, an exceptionally high degree of longitudinal instability. To resolve this incompatibility, a multiple degree of freedom model is developed with minimal requisite complexity to examine the hypothesis that the bird shoulder joint may embed essential stabilizing and preflexive mechanisms for rejecting rapid perturbations while simplifying and reducing control effort. Thus, the formulation herein is centrally premised upon distinct wing pitch and body pitch angles coupled via a Kelvin–Voigt viscoelastic shoulder joint. The model accurately exhibits empirical gust response of an unstable gliding raptor, generates biologically plausible equilibrium configurations, and the viscoelastic shoulder coupling is shown to drastically alleviate the high degree of instability predicted by conventional linear flight dynamics models. In fact, stability analysis of the model predicts a critical system timescale (the time to double amplitude of a pitch divergence mode) that is commensurate with in vivo measured latency of barn owls (Tyto alba). Active gust mitigation is studied by presupposing the owl behaves as an optimal controller. The system is under-actuated and the feedback control law is resolved in the controllable subspace using a Kalman decomposition. Importantly, control-theoretic analysis precisely identifies what discrete gust frequencies may be rapidly and passively rejected versus disturbances requiring feedback control intervention.
The use of δ
13C in CO to determine removal of CH4 by Cl radicals in the atmosphere
*
Authors: Röckmann Thomas , van Herpen Maarten , Brashear Chloe , van der Veen Carina , Gromov Sergey , Li Qinyi , Saiz-Lopez Alfonso , Meidan Daphne , Barreto Africa , Prats Natalia , Mármol Ignacio , Ramos Ramón , Baños Isabel , Arrieta Jesús M , Zaehnle Sönke , Jordan Armin , Moossen Heiko , Timas Helder , Young Dickon , Sperlich Peter , Moss Rowena , Johnson Matthew S 
Published: April 2024

Abstract
The reaction of CH4 with chlorine (Cl) radicals in the atmosphere is associated with an extraordinarily strong isotopic fractionation, where 12CH4 reacts about 70 ‰ faster with Cl than 13CH4. Therefore, although the Cl-based sink of CH4 constitutes only a small contribution to its total removal rate, the uncertainty in this small sink has been identified as one of the two largest uncertainties of isotope-based CH4 source apportionment at the global scale. The uncertainty arises from the fact that Cl levels in the atmosphere are so low that they cannot be detected directly. One very sensitive indirect method to identify and quantify the CH4 + Cl reaction in the atmosphere is the detection of the extremely 13C-depleted reaction product carbon monoxide (CO) from this reaction. This article reviews the concept of this approach, its successful application in the atmosphere, its challenges and opportunities for identifying and quantifying Cl-based removal of CH4 at the regional and global scale and its potential to detect and evaluate possible attempts to enhance CH4 removal from the atmosphere.
Linking physical climate risk with mandatory business risk disclosure requirements
Authors: Pitman A J , Saribatir E , Greenhill C , Green S , Pitman S J , Fiedler T 
Published: April 2024

Abstract
Mandatory disclosure of physical climate risks to businesses is planned or being implemented in many countries. This raises the question, how viable is it to link increasing physical climate risk, expressed as extreme events, to an individual business. We demonstrate how the characteristics of increasing frequency, magnitude and duration of extreme events impact a hypothetical business supply chain using the analogy of a spider’s web, where an extreme event impacting a strand of the web (supply/market line) impacts the efficiency of the web (supply chain). We demonstrate that our hypothetical business, located in the centre of the web, can be unaffected by a very large number of extreme events, or be severely impacted by a small number of events, depending on exactly where the event occurs and the properties of the event. This implies that a business cannot assess physical climate risk based on a change in the frequency of events; the business needs to know the precise location of the events, as well as the magnitude and duration of each event. This information is not available and is unlikely to ever be available from climate model projections. Therefore, individual businesses required to disclose future physical climate risk are very unlikely to be able to provide useful quantitative assessments. We recommend that a business-specific storyline approach to future risk is used where multiple lines of evidence are woven into a risk assessment, including climate projections. Generic top–down prescriptions of future scenarios are very likely to lead to misrepresentation of risk and very poor outcomes for business, investors or financial regulators seeking to build resilience to future climate change.