bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of bi-doped on MAPb(IxBr1–x)3 mixed halide perovskite films
Authors: Pengpad Atip , Rattanachata Arunothai , Rattanasuporn Surachet , Jenpiyapong Watcharapon , Nakajima Hideki , Kumnorkaew Pisist , Jarernboon Wirat , Amornkitbamrung Vittaya
Published: April 2024

Perovskite solar cells have attracted considerable attention from researchers owing to their cost-effective manufacturing processes, facilitating their suitability for commercialization. Halide perovskite such as methylammonium lead iodide (MAPbI3), methylammonium lead bromide (MAPbBr3) and other mixed halide perovskite are intensively studied as light absorber for solar cells. In order to adjust the properties of the perovskite, doping with heterovalent metal ions such as bismuth iodide, BiI3, has demonstrated notable impact on both crystal structure and optical properties. Traditionally, Bi3+ doping has been conducted primarily in single halide perovskite. However, our study explored the possibility of Bi3+ doping at a concentrations of 5% in mixed halide perovskite, specifically the mixed iodide-bromide perovskite, MAPb(IxBr1–x)3 at x = 0.2, 0.4, 0.6 and 0.8. The XRD results revealed a decrease in lattice constant upon Bi3+ doping which likely attributed to the smaller ionic radius of Bi3+ compared to Pb2+. The light absorption spectra of Bi3+ doping perovskites exhibited a significant red shift compared to the undoped samples. The presences of the key elements are confirmed by photoemission spectroscopy results. Moreover, our investigation found no notable effect on the valence band maximum upon doping. The observed red-shift presents a potential advantage for precisely adjusting the absorption edge in tandem solar cells, particularly when specific energy gaps are required.
Detection performance of flower-like hydrothermally synthesized ZnO in silicon-type photodetector
Authors: Eden Cigdem , Kocyigit Adem , Aydogan Sakir , Cirak Cagri , Yilmaz Mehmet
Published: April 2024

Zinc oxide (ZnO) is a versatile compound or metal oxide with a wide range of applications across various industries such as electronics, optoelectronics, and gas sensors, etc. A simple hydrothermal method was used to synthesize ZnO flower-like structures in this study. The synthesized ZnO structures were analyzed by x-ray diffractometer (XRD) and scanning electron microscope (SEM). We used ZnO structures as an interfacial layer for a Schottky-type silicon-based photodetector. While Au and Al metals were employed as metallic and ohmic contacts, respectively, p-Si was utilized as a semiconductor and substrate. Thus, Au/ZnO/p-Si sandwich was successfully fabricated and tested by current–voltage (I–V) measurements under dark and various light power illumination densities from 10 mW cm−2 to 150 mW cm−2 as well as the various wavelengths in the case of same power. The I–V characteristics were used to determine the diode and photodetection parameters. The fabricated heterostructure exhibited 77.51 mA W−1 responsivity, 1.30 × 1010 Jones specific detectivity, and 26.33% external quantum efficiency (EQE) values.
Laser-beam powder bed fusion of magnetostrictive Fe81Ga19 alloys: parameter optimization, microstructural evolution and magnetostrictive properties
Authors: Yao Xiong , Deng Woding , Wang Liyuan , Gao Chengde , Shuai Cijun
Published: April 2024

Magnetostrictive Fe-Ga alloys, featuring with good machinability, high Curie temperature, and high permeability, have received increasing attention in fields such as actuators, implants, and energy harvesting. Unfortunately, bulk polycrystalline Fe-Ga alloys usually suffer poor magnetostrictive strains compromised by the randomness of grain structure and the intricate phase constitution. The current study was centered on the fabrication of bulk polycrystalline Fe81Ga19 alloys with tailored grain morphology and phase arrangement utilizing laser-beam powder bed fusion (LPBF) technology. Particular emphasis was laid on investigating the repercussions of LPBF process parameters on the microstructure and magnetostrictive performance. The findings illustrated a non-linear interplay between laser power and the relative density of laser powder bed fusion-fabricated (LPBFed) Fe81Ga19 alloys, marked by an initial augmentation followed by a subsequent decrement. Similarly, a consistent trend was observed for the LPBFed alloys at varying scan speeds. In particular, the LPBFed Fe81Ga19 alloys exhibited a highest density at optimized process parameters (laser power set at 120 W paired with a scan speed of 100 mm s−1) due to suitable laser energy input during LPBF process. It was experimentally shown that elongated columnar grains and disorder A2 phase structures were obtained within the alloys attibutes to the high temperature gradient and rapid cooling kinetics intrinsic to LPBF, contributing to a desirable magnetostrictive strain of ∼87 ppm for bulk polycrystalline Fe81Ga19 alloys. Moreover, a good dynamic magnetostrictive response of the LPBFed alloys was confirmed by the near-synchronous variations between magnetostrictive behavior and alternating magnetic fields. It can be derived from these findings that LPBF process may be a promising method to prepare bulk magnetostrictive Fe-Ga alloys for versatile applications.
Electronic structure and magnetic properties of Si doped AlFe2Ge full-Heusler
Authors: Kadim G , Masrour R
Published: April 2024

Using spin-polarized GGA combined with TB-mBJ approach and Monte Carlo simulation, we systematically explore the electronic and magnetic properties of cubic Al1-xSixFe2Ge (x = 0, 0.25, 0.50, 0.75, and 1) compounds. Structural optimization in the ferromagnetic and ferrimagnetic state proves that the AlFe2Ge alloy is ferrimagnetic with an enhanced lattice constant of 3.6075 Å. Elastic constants and related mechanical quantities such as bulk modulus B, Zener anisotropy factor A and Cauchy pressure Cp were calculated. The calculated total magnetic moments decrease with increasing Si concentration. The total magnetic moments of AlFe2Ge and SiFe2Ge compounds are fully compatible with the Slater-Pauling rule. The results show that the studied compound has remarkable properties such as high magnetic entropy at low temperature 40 J.kg−1.K−1, metallicity and ferrimagnetism. Noting that ferrimagnetic compound is more suitable for spintronic devices than the ferromagnetic compound due to its lower leakage fields and favorable robustness of magnetism.
Optical soliton solutions of the perturbed fourth-order nonlinear Schrödinger-Hirota equation with parabolic law nonlinearity of self-phase modulation
Authors: Altun Selvi , Secer Aydin , Ozisik Muslum , Bayram Mustafa
Published: April 2024

This article introduces an examination of optical soliton solutions for the perturbed fourth-order nonlinear Schrödinger-Hirota equation, which plays a crucial role in optics. For the first time, it utilizes a novel approach by applying the extended auxiliary equation method. This equation models the propagation of optical pulses through nonlinear media, such as optical fibers, and has been the subject of many studies. Our goal extends beyond merely acquiring a significant number of soliton solutions using the method described in this article; we also aim to investigate the impact of the coefficients of group velocity dispersion, parabolic law, and fourth-order dispersion terms on soliton propagation in the problem examined. The 2D, 3D, and contour plots of the acquired dark and bright solitons, which represent the most fundamental soliton types, are presented. Additionally, all other calculations are performed using symbolic algebraic software. The results provide us with valuable insights, confirming that the introduced model can be analyzed from a physical perspective. It is demonstrated that the proposed technique is not only important but also efficient in analyzing various nonlinear scientific problems.
Research on the Optimal Design of the High-stability Optical System for Atmospheric Spectra in Transit Observation
Authors: Wang Fang
Published: April 2024

Capturing the characteristics of exoplanetary atmospheres (CEA) through transit spectroscopy (TS) holds profound implications for our understanding of planetary formation and evolution. However, TS, the method employed for detecting CEA, indirectly extracts these characteristics from the subtle variations in stellar spectra during the transit process, necessitating a high level of observational stability in optical instrumentation. To mitigate observational errors in spectral energy within the optical system, this dissertation delves into the optimal design of a high-stability optical system tailored for atmospheric spectra in transit observations. Initially, a theoretical model of transit signal-to-noise ratios (S/Ns) catered to the EAC retrievals is formulated based on transit observation strategies. Subsequently, the optimal parameters and design approach for the optical system are explored through an analysis of the optical factors influencing S/N. Leveraging an observation simulator for optical instruments, the detection feasibility of the optimized optical system for capturing CEA is validated.
Critical behavior and Joule-Thomson expansion of charged AdS black holes surrounded by exotic fluid with modified Chaplygin equation of state*
Authors: Zhang 张 Meng-Yao 梦瑶 , Chen 陈 Hao 浩 , Hassanabad Hassan , Long 隆 Zheng-Wen 正文 , Yang 杨 Hui 辉
Published: April 2024

By considering the concept of a unified single fluid model, referred to as modified Chaplygin gas (MCG), which amalgamates dark energy and dark matter, we explore the thermodynamic characteristics of charged anti-de Sitter (AdS) black holes existing in an unconventional fluid accompanied by MCG. To accomplish this objective, we derive the equations of state by regarding the charge

as a thermodynamic variable. The effects of MCG parameters on the critical thermodynamic quantities (

,

,

) are examined, followed by a detailed analysis of the

diagram. To provide a clearer explanation of the phase transition, we present an analysis of the Gibbs free energy. It is important to note that if the Hawking temperature exceeds the critical temperature, a distinct pattern is observed known as swallowtail behavior. This indicates that the system undergoes a first-order phase transition from a smaller black hole to a larger one. The critical exponent of the system is found to be in complete agreement with that of the van der Waals fluid system. Furthermore, we investigate the impact of MCG parameters and black hole charge on Joule-Thomson (J-T) expansion in the extended phase space. The J-T coefficient is examined to pinpoint the exact region experiencing cooling or heating, and the observation reveals that the presence of negative heat capacity results in the occurrence of a cooling process. The impact of MCG on the inversion curve of charged black holes exhibits a striking resemblance to that observed in most multi-dimensional black hole systems. In addition, it is worth noting that certain parameters exert a significant influence on the ratio

. For specific values of the MCG parameters, the ratio is consistent with the charged AdS black hole. The parameters γ and β have a non-negligible effect on the isenthalpic curve.
Analysis of strong decays of SU(3) partners of Ω(2012) baryon
Authors: Aliev T. M. , Bilmis S. , Savci M.
Published: April 2024

We estimate the coupling constants and decay widths of the

partners of the

hyperon, as discovered by the BELLE Collaboration, using the distribution amplitudes of the octet baryons within the light cone sum rules method. Our study includes a comparison of the obtained results for the relevant decay widths with those derived within the framework of the flavor

analysis. We observe a good agreement between the predictions of both approaches. Moreover, our result on the decay width of

is compatible with the existing experimental result within the uncertainties of the model predictions. These results can provide helpful insights for determining the nature of the

partners of the

baryon.
Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr
Authors: El jariri Y. , Sefyani F.L. , Benhida A. , Benkhaldoun Z. , Kolenberg K. , Chafouai K. , Habib A. , Sabil M.
Published: April 2024

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating stars. In this article, we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 yr. We based ourselves, on the one hand, on 1268 spectra (41 nights of observation) recorded between the years 1994 and 1997 at the Observatory of Haute Provence (OHP, France) previously observed by Chadid and Gillet, and on the other hand on 1569 spectra (46 nights of observation) recorded at our Oukaimeden Observatory (Morocco) between 2015 and 2016. Through this study, we have detected information on atmospheric dynamics that had not previously been detected. Indeed, the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases. A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as well. For the first time, we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of Fe ii (λ4923.921 Å) increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko cycle. Furthermore, we found that the Van Hoof effect is also modulated by the Blazhko effect. Thus, toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle, this effect is minimal. We also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper atmosphere. When observed over a long time, we can interpret it as a function of the Blazhko phases.
The First Ground-based White Light Lunar Polarization Imaging: A New Kind of FeO Observation on the Near Side of the Moon
Authors: Wang Wei-Nan , Ping Jin-Song , Wang Ming-Yuan , Zhang Wen-Zhao , Ye Han-Lin , Han Xing-Wei , Kou Song-Feng
Published: April 2024

Lunar optical polarization is a fascinating phenomenon that occurs when sunlight reflects off the surface of the Moon and becomes polarized. This study employs a novel split-focus plane polarimetric camera to conduct the initial white light polarimetric observations on the near side of the Moon. We obtained the linear degree of polarization (DOP) parameters of white light by observation from the eastern and western hemispheres of the Moon. The findings indicate that the white light polarization is lower in the lunar highland than in the lunar maria overall. Combining the analysis of lunar soil samples, we noticed and determined that the DOP parameters of white light demonstrate high consistency with iron oxide on the Moon. This study may serve as a new diagnostic tool for the Moon.
Repeated mining accounts for the majority of artisanal and small-scale gold mining activity in Southeastern Peru
Authors: Engstrand Rachel C , Espejo Jorge Caballero , Silman Miles R , Asner Gregory P
Published: April 2024

Artisanal and small-scale gold mining (ASGM) is considered a leading cause of environmental degradation in the Amazon. Previous studies have only used deforestation to quantify total ASGM activity and have not considered that mining may occur multiple times in the same area. However, miners often revisit previously mined sites to extract additional gold, though the frequency and extent of this occurrence remains unquantified. This study is the first to quantify repeat ASGM in Madre de Dios, Peru, and to identify which factors best predict revisitation. We found that nearly two-thirds of total ASGM activity in this region is repeat mining. When repeat mining activity is accounted for, we found that 249 488 ha were mined from 1984–2021, which is 265% more than activity estimates based on deforestation due to initial ASGM alone. Random Forest modeling showed that the designation, region, size, and type of a mine were the most important predictors of repeat mining. We suggest that repeat mining must be considered for a more comprehensive view of ASGM activity and its environmental impacts.
Exploring the spectral variation hypothesis for α- and β-diversity: a comparison of open vegetation and forests
Authors: Wallis Christine I B , Kothari Shan , Jantzen Johanna R , Crofts Anna L , St-Jean Sabine , Inamdar Deep , Pablo Arroyo-Mora J , Kalacska Margaret , Bruneau Anne , Coops Nicholas C , Laliberté Etienne , Vellend Mark
Published: April 2024

Airborne hyperspectral imaging holds great promise for estimating plant diversity and composition, given its unprecedented combination of aerial coverage, spatial resolution, and spectral detail. Recently, there has been renewed attention toward the spectral variation hypothesis (SVH), which predicts that higher spectral variation is correlated with greater plant diversity. While several studies have highlighted methodological challenges involved with the SVH, there is little consensus about when it yields strong predictions of taxonomic, functional, and phylogenetic diversity. In part, this may be because prior studies have not explicitly considered how underlying environmental gradients drive changes in spectral and species composition. In this study, we tested the SVH separately in open vegetation (i.e. grasses and shrubs) and in forests at five sites across Canada. Generalized additive models revealed that spectral diversity was a better predictor of functional α-diversity than of taxonomic or phylogenetic α-diversity in both vegetation types. Mantel tests and Procrustes analyses revealed weak to moderate associations between spectral and plant β-diversity and composition in open vegetation, and moderate associations in forests. The better fit in forests appeared to be influenced by the presence of an elevational gradient and associated species turnover (from deciduous to coniferous trees); we observed weaker relationships when examining only a subset of this gradient. We suggest that the high variability in the strength of associations between plant and spectral diversity reported to date might be affected by the presence of environmental gradients. Finally, we found that different wavelength bands contributed to spectral α-diversity in open vegetation vs. forests, suggesting different spectral features are important for different vegetation types. In conclusion, spectral diversity is a potentially powerful tool for biodiversity assessment, but it requires a context-specific approach.
Revealing neglected hotspots for China’s quality-induced water scarcity
Authors: Liu Shuman , Liu Junguo , Zhao Dandan , Cao Wenfang
Published: April 2024

A dependable assessment of quality-induced water scarcity (QualWS) is essential for tackling the issue and achieving sustainable development goals. The conventional Emission-based grey water footprint (GWF) may over- or under-estimate QualWS, as it solely focuses on local pollutant emissions while disregarding other influential factors, such as water body self-purification capacity, transboundary water flows and the potential under- or over-estimation of water pollution emissions. To address this limitation, we propose the State-based GWF to reflect the quality status of local water resources accurately. The indicator is applied in annual and monthly QualWS assessments at the provincial scale in China. In 2021, 19 provinces were identified as QualWS hotspots, comprising seven moderate and 12 slight hotspots for at least one pollutant. Notably, the State-based assessment revealed eight previously overlooked hotspots undetected by conventional methods. Furthermore, total phosphorus emerged as the most critical water pollutant, followed by total nitrogen and chemical oxygen demand. Our assessment presents an innovative perspective for understanding QualWS and establishes a scientific basis for effective aquatic environment management.
Association between hydrometeorological conditions and infectious diarrhea in mainland China: a spatiotemporal modeling study
Authors: Yu Wenhao , Zhuang Mengwei , Geng Mengjie , Hu Kejia , Zhao Qi , Yan Jie
Published: April 2024

Infectious diarrhea imposes substantial disease burden in China, with local climate identified as a key risk factor. In this study, we aimed to explore the association between hydrometeorological conditions and the incidence of infectious diarrhea, and investigate the modification effect of urbanization, which remained unclear previously. Monthly data were collected from 1 January 2021 to 31 December 2022 from each city of mainland China on cases of infectious diarrhea other than cholera, dysentery, typhoid and paratyphoid (i.e. other infectious diarrhea, OID), temperature and precipitation. We used Palmer drought severity index (PDSI) to represent local hydrometeorological conditions (dry and wet). A spatiotemporal Bayesian hierarchical model combined with distributed lag nonlinear model was specified to explore the association between PDSI and the relative risk of OID. The effect size of hydrometeorological conditions at different urbanization levels were quantified through a linear interaction term. A total of 1999 947 OID cases were included. There was a N-shaped cumulative association between PDSI and OID incidence over a maximum lag of 4 months. The effect of extreme dry conditions persisted over lag 1–3 months and peaked at the 2-month lag (RR = 2.67, 95%CI: 2.44–2.91). By contrast, the relative risk of OID increased immediately under extreme wet conditions (RR = 1.97, 95%CI: 1.68–2.32 at lag 0 month). Children and the older population were particularly susceptible to extreme dry and wet conditions, respectively. Areas with lower urbanization rate, healthcare resources and economic levels, and higher population density showed a higher risk of OID related to extreme dry conditions. While the modification effects of these urbanization characteristics were limited for extreme wet conditions. There was a nonlinear and lagged association between hydrometeorological conditions and the incidence of OID in mainland China, which may be modified in diverse patterns by urbanization indicators. Our findings will provide valuable reference for better prevention and control of OID.
Freddy: breaking record for tropical cyclone precipitation?
Authors: Scoccimarro Enrico , Lanteri Paolo , Cavicchia Leone
Published: April 2024

Depending on the location on the Earth, the amount of precipitation associated with tropical cyclones (TCs) can reach 20% of the total yearly precipitation over land and up to 40% over some ocean regions. TC induced freshwater flooding has been suggested to be the largest threat to human lives due to TCs. Therefore, a reliable quantification of the precipitation amount associated with each past TC is important for a better definition of the TC fingerprint on the climate. The temporal and horizontal resolution of state-of-the-art observational datasets and atmospheric reanalysis gives the possibility to quantify precipitation associated with TCs globally following the observed TC tracks. In this work we compare the TC-related precipitation in various observational and reanalysis datasets. A particular focus is given to the record-breaking TC Freddy (Southern Indian Ocean, 2023). Here we show that the time-varying bias in TC associated precipitation, due to the positive trend in assimilated observations, makes it difficult to assess long-term trend investigation based on reanalysis. To this aim we need to build on state-of-the-art general circulation models, free to evolve under historical radiative forcing.
What is still at stake in the Gran Chaco? Social-ecological impacts of alternative land-system futures in a global deforestation hotspot
Authors: Levers Christian , Piquer-Rodríguez María , Gollnow Florian , Baumann Matthias , Camino Micaela , Gasparri Nestor Ignacio , Gavier-Pizarro Gregorio Ignacio , le Polain de Waroux Yann , Müller Daniel , Nori Javier , Pötzschner Florian , Romero-Muñoz Alfredo , Kuemmerle Tobias
Published: April 2024

Commodity agriculture continues to spread into tropical dry forests globally, eroding their social-ecological integrity. Understanding where deforestation frontiers expand, and which impacts this process triggers, is thus important for sustainability planning. We reconstructed past land-system change (1985–2015) and simulated alternative land-system futures (2015–2045) for the Gran Chaco, a 1.1 million km2 global deforestation hotspot with high biological and cultural diversity. We co-developed nine plausible future land-system scenarios, consisting of three contrasting policy narratives (Agribusiness, Ecomodernism, and Integration) and three agricultural expansion rates (high, medium, and low). We assessed the social-ecological impacts of our scenarios by comparing them with current biodiversity, carbon density, and areas used by forest-dependent people. Our analyses revealed four major insights. First, intensified agriculture and mosaics of agriculture and remaining natural vegetation have replaced large swaths of woodland since 1985. Second, simulated land-system futures until 2045 revealed potential hotspots of natural vegetation loss (e.g. western and southern Argentinian Chaco, western Paraguayan Chaco), both due to the continued expansion of existing agricultural frontiers and the emergence of new ones. Third, the strongest social-ecological impacts were consistently connected to the Agribusiness scenarios, while impacts were lower for the Ecomodernism and Integration scenarios. Scenarios based on our Integration narrative led to lower social impacts, while Ecomodernism had lower ecological impacts. Fourth, comparing recent land change with our simulations showed that 10% of the Chaco is on a pathway consistent with our Agribusiness narrative, associated with adverse social-ecological impacts. Our results highlight that much is still at stake in the Chaco. Stricter land-use and conservation planning are urgently needed to avoid adverse social-ecological outcomes, and our results charting the option space of plausible land-system futures can support such planning.
High Q chiroptical responses with maximum chirality in all-dielectric metasurfaces driven by quasi-bound states in the continuum
Authors: Ma Tian , Tian Jiangkun , Sang Wei , Wang Doudou , Li Jun
Published: April 2024

Chiral metasurfaces have attracted considerable attention because of their immense potential for diverse applications requiring chiral light-matter interactions. Recently, boosted by a mechanism based on the concept of bound states in the continuum (BICs), high Q factor chiroptical resonances have been exhibited by breaking the inversion symmetries of planar metasurfaces. However, the optical chirality of these chiral metasurfaces is generally intolerable with respect to the structural geometries, especially the geometric asymmetry. Here, we present a novel chiral quasi-BIC with strong optical chirality in an all-dielectric metasurface. By simultaneously breaking the in-plane

C
2

rotational and mirror symmetries, the chiral metasurface shows enhanced chiroptical resonances with near-unity CD (∼0.996) and high Q factors (∼2274) at terahertz frequencies. Further analyses based on numerical simulations reveal that the CD of the chiroptical resonance depicts exceptional remarkable tolerableness to the geometry asymmetry

δ

when

δ

are present in a broad range, while the corresponding Q factor is modulated accordingly. The results may develop a novel approach to manipulating the advanced optical chirality for potential applications requiring strong CD with enhanced light-matter interactions.
Online nonlinearity elimination for fringe projection profilometry using slope intensity coding
Authors: Wan Yingying , Tang Tao , Li Jinlong , Yang Kai , Zhang Yu , Peng Jianping
Published: April 2024

The nonlinearity effect in the system of fringe projection profilometry can cause the non-sinusoidal deviation of the fringe patterns, inducing ripple-like phase errors and further affecting measurement accuracy. This paper presents an online nonlinearity elimination method based on slope intensity coding. Two sequences of sinusoidal phase-shifting fringe patterns with different frequencies, and one slope intensity pattern with one uniform intensity pattern are projected. The equations for the nonlinearity response are established using the defined mean and modulation parameters, the captured uniform intensity and two extracted background intensities. The nonlinearity response coefficients determined by solving the equations are used for pixel-wise nonlinearity correction on the captured images, which are employed for computing the wrapped phase, and further obtaining continuous phase by the multi-frequency phase unwrapping method. Experimental results demonstrate that the proposed method can eliminate the nonlinearity-induced phase error online by using fewer images and maintain the reliability of phase unwrapping in the measurement of isolated objects with complex surfaces.
One-step hydrothermal preparation of corrosion-resistant coatings with microsphere structure
Authors: Chen Shengli , Zhu Jiyuan
Published: April 2024

Rapid corrosion rate is limiting the engineering application of magnesium alloys. In this paper, an attempt was made to produce a corrosion resistant coating on the surface of AZ91D magnesium alloy using hydrothermal method. The coating surface is covered with microspheres and has a dense structure, which effectively isolates the contact between the outside world and the substrate. The corrosion potential(E) raised from −1.57 V to −0.45 V compared to the bare sample. The corrosion current density and corrosion rate of the coating can be reduced by 6 orders of magnitude, and the polarization resistance raised by 6 orders of magnitude. The thickness of the coating is 45.4 μm at the moment, with a minimum of defects on the surface, resulting in excellent corrosion resistance in the immersion test. The coating also has good adhesion strength at 4B, which can expand the application range of magnesium alloy in corrosive environments.
Comparative assessment of supervised machine learning algorithms for predicting geometric characteristics of laser cladded inconel 718
Authors: Yang Hao , Geng Heran , Alfano Marco , Yuan Junfeng
Published: April 2024

Laser cladding, an innovative surface modification and coating preparation process, has emerged as a research hotspot in material surface modification and green remanufacturing domains. In the laser cladding process, the interaction between laser light, powder particles, and the substrate results in a complicated mapping connection between process parameters and clad layer quality. This work aims to shed light on this mapping using fast evolving machine learning algorithms. A full factorial experimental design was employed to clad Inconel 718 powder on an A286 substrate comprising 64 groups. Analysis of variance, contour plots, and surface plots were used to explore the effects of laser power, powder feeding rate, and scanning speed on the width, height, and dilution rate of the cladding. The performance of the predictive models was evaluated using the index of merit (IM), which includes mean square error (MSE), mean absolute error (MAE), and coefficient of determination (R2). By comparing the performance of the models, it was found that the Extra Trees, Random forest regression, Decision tree regression, and XGBoost algorithms exhibited the highest predictive accuracy. Specifically, the Extra Trees algorithm outperformed other machine learning models in predicting the cladding width, while the RFR algorithm excelled in predicting the associated height. The DTR algorithm demonstrated the best performance in predicting the cladding dilution rate. The R2 values for width, height, and dilution rate were found to be 0.949, 0.954, and 0.912, respectively, for these three models.
Mixture ratio optimization of basalt fiber recycled aggregate concrete based on RSM
Authors: Li Xiang , Sun Xiaomeng
Published: April 2024

In this paper, the effects of W/B ratio, recycled aggregate (RA) content and basalt fiber (BF) dosage on the compressive strength, splitting tensile strength and slump of concrete were investigated and a regression model was developed for analysis and prediction, and the regression model was validated using ANOVA and confidence analysis. Statistical analysis revealed that W/B ratio, RA content and BF dosage had significant effects on all properties of concrete. The established regression model fits the experimental data well and can accurately predict the properties of concrete. It was also found that there was a significant interaction between W/B ratio and BF dosage, as well as RA content and BF dosage, which suggests that the combination of these factors should be considered in the design of concrete mixture ratio to achieve optimum performance. The predicted values of compressive strength, split tensile strength and slump of concrete under optimum proportioning were in good agreement with the experimental values. Therefore, optimizing the concrete proportion by response surface methodology can improve the testing efficiency and obtain basalt fiber recycled aggregate concrete that meets the design requirements and has better overall performance.
Impact of digital economy on urban land green use efficiency: evidence from Chinese cities
Authors: Wen Rou , Li Hongyi
Published: April 2024

Improving urban land green use efficiency (ULGUE) is essential for achieving the sustainable use of land resources and the high-quality economic development of cities. The digital economy has overcome spatial and locational constraints, blurred the boundaries between industries, and created a collaborative and open economic model, inevitably affecting urban land utilization. However, whether the digital economy will affect ULGUE and how such an effect would take place are still unclear. This study evaluates the digital economy and ULGUE of Chinese cities from 2011 to 2019 and systematically analyzes both the direct and indirect impact mechanisms through which the digital economy affects ULGUE. The results show that the digital economy can significantly enhance ULGUE, and these results prove to be reliable, as shown by various endogeneity treatments and robustness tests. The digital economy enhances ULGUE by optimizing the industrial structure (structural effect), increasing green technology innovation (technical effect), and agglomerating digital talent (scale effect). Moreover, land finance dependency plays an adverse moderating role in the relationship between the digital economy and ULGUE. Further heterogeneity analysis shows that the promoting effect of the digital economy on ULGUE takes full effect in the eastern cities, larger cities, and cities with high levels of digital economy development and land marketization. This paper presents recommendations for supporting the balanced and integrated development of the digital economy across regions and provides differentiated development strategies to enhance ULGUE in the context of digitization.
Machine learned environment-dependent corrections for a
spds∗
empirical tight-binding basis
Authors: Soccodato Daniele , Penazzi Gabriele , Pecchia Alessandro , Phan Anh-Luan , Auf der Maur Matthias
Published: April 2024

Empirical tight-binding (ETB) methods have become a common choice to simulate electronic and transport properties for systems composed of thousands of atoms. However, their performance is profoundly dependent on the way the empirical parameters were fitted, and the found parametrizations often exhibit poor transferability. In order to mitigate some of the the criticalities of this method, we introduce a novel Δ-learning scheme, called MLΔTB. After being trained on a custom data set composed of ab-initio band structures, the framework is able to correlate the local atomistic environment to a correction on the on-site ETB parameters, for each atom in the system. The converged algorithm is applied to simulate the electronic properties of random GaAsSb alloys, and displays remarkable agreement both with experimental and ab-initio test data. Some noteworthy characteristics of MLΔTB include the ability to be trained on few instances, to be applied on 3D supercells of arbitrary size, to be rotationally invariant, and to predict physical properties that are not exhibited by the training set.
The role of the basic state in the climate response to future Arctic sea ice loss
Authors: Sigmond M , Sun L
Published: April 2024

There is great uncertainty in the atmospheric circulation response to future Arctic sea ice loss, with some models predicting a shift towards the negative phase of the North Atlantic Oscillation (NAO), while others predicting a more neutral NAO response. We investigate the potential role of systematic model biases in the spread of these responses by modifying the unperturbed (or ‘control’) climate (hereafter referred to as the ‘basic state’) of the Canadian Earth system model version 5 (CanESM5) in sea ice loss experiments based on the protocol of the Polar Amplification Model Intercomparison Project. We show that the presence or absence of the stratospheric pathway in response to sea ice loss depends on the basic state, and that only the CanESM5 version that shows a weakening of the stratospheric polar vortex features a strong negative NAO response. We propose a mechanism that explains this dependency, with a key role played by the vertical structure of the winds in the region between the subtropical jet and the stratospheric polar vortex (‘the neck region winds’), which determines the extent to which anomalous planetary wave activity in response to sea ice loss propagates away from the polar vortex. Our results suggest that differences in the models’ basic states could significantly contribute to model spread in the simulated atmospheric circulation response to sea ice loss, which may inform efforts to narrow the uncertainties regarding the impact of diminishing sea ice on mid-latitude climate.
Headlining mental health in a changing climate: a systematic analysis of climate change and mental health news coverage from Canada and the United States
Authors: Aylward Breanne , Cunsolo Ashlee , Vriezen Rachael , Bayne Hannah L , King Nia , Harper Sherilee
Published: April 2024

Climate change exerts a profound and far-reaching toll on mental health, resulting in mental illness, diminished wellbeing, and strained social relations, with the severity of these impacts anticipated to intensify under future climate change. News coverage of climate-mental health issues can shape public perceptions and responses, and therefore understanding this coverage is vital for creating and implementing strategies to lessen climate-mental health risks. We systematically examined the extent, nature, and range of news articles from Canada and the United States that covered climate-mental health impacts. Five electronic databases were searched. Articles were included if they were print or online news stories that covered climate-mental health impacts and were published in English or French by sources in Canada or the United States between 2016 and 2020. A total of 1085 articles (642 unique stories) met the inclusion criteria and underwent data extraction and analysis using descriptive statistics and thematic analysis. Coverage of climate-mental health outcomes increased in both Canada and the United States from 2016 to 2019. There was, however, a substantial decrease in coverage by Canadian news outlets from 2019 to 2020. Further, although 468 different news outlets published at least one story on the topic, repeat coverage by any one news outlet was infrequent. Most opinion pieces presented climate-mental health impacts as legitimate or expressed support for people experiencing these issues. Roughly half of the included stories identified populations that are vulnerable to climate-mental health impacts, particularly children and young people. Additionally, approximately half of the included stories identified potential interventions or coping strategies to protect mental health, most often involving changes to individual lifestyles or behavior. More sustained coverage that focuses on protective factors, interventions, and coping strategies is needed, as this could help foster public understanding and drive action to reduce climate-mental health risks.
A systematic review of urban green and blue spaces and cognitive function including discussion of mechanistic pathways
Authors: Glover Sophie , Cleland Claire L , Trott Mike , Hunter Ruth F
Published: April 2024

Urban green and blue spaces (UGBSs) have been found to have health-enhancing properties (e.g. promotion of physical activity, improved social connectedness, and stress reduction). We examined the associations between UGBSs and cognitive function and aimed to identify any mechanistic pathways involving UGBSs and cognitive function. The initial search of four databases (MEDLINE, Embase, PSYCHInfo, and Web of Science) yielded 4838 studies when duplicates were removed to undergo abstract screening. Following abstract and full text screening, the included studies were classified as ‘observational’ (proximity to UGBSs, n = 28/35) or ‘interventional’ (n = 7/35). Of the included studies, 71.4% (n = 24/28) of ‘observational’ studies and 57.1% (n = 4/7) of ‘interventional’ studies found positive associations indicating that UGBSs are beneficial for cognitive function (i.e. enhance cognitive function, lower risk of cognitive impairment, or protect cognitive function). Overall, 71.4% (n = 20/35) of studies included within this review were considered to have a medium risk of bias. Current studies have identified relationships between UGBSs and cognitive function; however, further work is required globally to broaden our understanding and provide a reliable evidence base. Current literature has elucidated numerous mechanistic pathways by which UGBSs have the capacity to operate, including attention restoration theory and stress reduction theory. Advancing the evidence for the mechanistic pathways between UGBSs and cognitive function is required. This may advise future UGBS policies to improve the health and well-being of both the environment and the globally ageing population.
Depoliticization and State Authority
Authors: Schupmann Benjamin A
Published: April 2024

This chapter analyses the legitimacy of the state’s defence of its constitutional identity against internal challenges such as politicization, enemies, and legal revolution, using Carl Schmitt’s state and constitutional theory. Building on Thomas Hobbes’ state theory, Schmitt argues that the state possesses the right to defend its political identity through methods of constitutional entrenchment. Although formulated before the term ‘militant democracy’ emerged, Schmitt’s theory anticipated its principal mechanisms, including the unamendability of constitutional essentials and political rights restrictions. The chapter concludes by highlighting that while Schmitt’s thought provides the militant dimension of a liberal normative theory of militant democracy, it fails to provide any significant democratic aspects. Therefore, to fully realize a liberal normative theory of militant democracy, Schmitt’s formal arguments must be supplemented with substantive democracy theory.
Conclusion
Authors: Schupmann Benjamin A
Published: April 2024

The conclusion of this book underscores how ‘militant democracy’ is vital for entrenching democratic constitutional essentials against legal revolutionary threats. It argues for the use of proactive defensive measures to safeguard the political identity of democracy against its internal enemies. While emphasizing the importance of constitutional design in safeguarding democracy, the conclusion recognizes that militant democracy should be integrated into a broader defensive strategy. It argues that militant democracy’s focus on constitutional entrenchment should be paired with more proactive and longer-term solutions, such as improved social democracy and civic education. It concludes that a multifaceted defence is the best guarantee against the cannibalization of democracy.
Rapid examination of lung tissues by nonlinear microscopy
Authors: Sun Yue , Weber Timothy D , Fujimoto James G , Rosen Seymour , VanderLaan Paul A
Published: April 2024

Objectives

Traditional histopathology is a time-intensive and labor-intensive process involving tissue formalin fixation, paraffin embedding, and microtoming into thin sections for H&E staining. Frozen section analysis is a modality used during surgery to quickly evaluate tissue, but it has limitations, such as the size and number of the specimens that can be analyzed as well as difficulties with fatty and bony tissues. Our objective was to investigate the performance of nonlinear microscopy, a fluorescence microscopy technique, for the rapid examination of resected lung tumors.

Methods

In this proof-of-principle study, nonlinear microscopy imaging of resected lung tissue was performed on a total of 73 tissue specimens collected from 13 patients who underwent lobectomy, segmentectomy, or wedge resection for pulmonary nodules.

Results

Two pathologists reviewed the digital nonlinear microscopy images in comparison to the corresponding histopathologic H&E slides from a variety of pulmonary pathologies.

Conclusions

This study demonstrated that nonlinear microscopy readily replicates traditional H&E staining for both lung tumors and nonneoplastic pulmonary structures. Nonlinear microscopy provides many advantages over frozen section analysis and is an optical imaging platform that has the potential to augment rapid pathologic evaluation of resected tissues in the age of digital pathology.
How I diagnose systemic mastocytosis
Authors: Rets Anton V , George Tracy I
Published: April 2024

Objectives

Systemic mastocytosis (SM) is a neoplasm of mast cells (MCs) characterized by their proliferation in extracutaneous organs. Systemic mastocytosis includes several entities with different clinical courses and prognoses. The rarity of this disease and the diversity of clinical and morphologic presentation make the diagnosis of SM very challenging. The aim of this review is to share our approach to the diagnosis of SM.

Methods

We present 4 cases that highlight the spectrum of clinical and laboratory features of SM and outline the diagnostic process with an emphasis on morphology.

Results

Pathology and laboratory medicine play a key role in investigation of SM, as correct diagnosis requires integration of morphologic, molecular, and serologic findings. In addition to awareness of microscopic findings in SM, a pathologist must keep abreast with an expanding menu of ancillary studies, particularly molecular testing.

Conclusions

Systemic mastocytosis is a challenging diagnosis that requires not only a demonstration of a clonal proliferation of MCs but also a correct subclassification based on the recently updated criteria.