bluuebunny/crossref_metadata_2025_split huggingface dataset:
Most general isotropic charged fluid solution for Buchdahl model in ℱ(𝒬) gravity
Authors: Chaudhary Sourav , Maurya Sunil Kumar , Kumar Jitendra , Mustafa Ghulam 
Published: September 2024

Abstract
In this work, we investigated a most general isotropic charged fluid solution for the Buchdahl model via a two-step method in ℱ(𝒬)-gravity framework for the first time. In this context, a linear function of the form ℱ(𝒬) = ζ
1
𝒬 + ζ
2 and a particular transformation is used to solve the Einstein-Maxwell Equations (EMEs) employing the Buchdahl ansatz: e
Υ(r) = μ(1+λ r
2)/μ+λ r
2, where ζ
1, ζ
2, λ and μ are constant parameters. The Schwarzschild de Sitter (AdS) exterior solution is joined to the interior solution at the boundary to determine the constant parameters. It should be emphasized that, for a given transformation, the Buchdahl ansatz only offers a mathematically feasible solution in the context of electric charge, where pressure and density are maximum at the center and decrease monotonically towards the boundary when 0 < μ < 1. We taken into account the compact star EX01785-248 with M = (1.3±0.2)M
⊙; Radius = 12.02+0.55
-0.55 km for graphical analysis.
The physical acceptability of the model in the context of ℱ(𝒬) gravity has been evaluated by looking at the necessary physical properties, including energy conditions, causality condition, hydrostatic equilibrium, pressure-density ratio, etc. Additionally, we predicted the maximum mass limit of different compact objects for various parameter values along with the mass-radius relation. The maximum masses range (1.927 - 2.321) M
⊙ are obtained for our solution. It can be observed that when the coupling parameter ζ
1 for ℱ(𝒬 gravity is smaller, then our solution yields massive stars. The present investigation provides novel insights and realistic implications regarding the formation of compact astrophysical objects.
Spherical-like spectra for the description of the normal states of 108-120Cd in the SU3-IBM and the
anomaly*
Authors: Wang 王 Tao 涛 , Chen 陈 Xin 鑫 , Zhang 张 Yu 宇 
Published: September 2024

Abstract
The Cd puzzle implies that the phonon excitation of a spherical nucleus should be questioned and refuted. To understand the newly and experimentally discovered spherical-like γ-soft mode, the SU3-IBM was recently proposed. In this study, the evolutions of the normal states in

Cd are investigated and compared with the experimental results. To better explain the nearly zero B(E2) values between the

and

states, SU(3) higher-order interactions except for the SU(3) second-order and third-order Casimir operators are also considered in detail. We find that the results of theoretical fitting and experimental data agree well with simple parameter selection, and the spherical-like spectra truly exist. The deficiency may arise from the lack of configuration mixing. The realistic spectra characteristics of the spherical-like spectra are found for

Cd, and the electric quadrupole moments of the

state are predicted. The

anomaly in

Cd is also discussed.
High Speed Tracking of the Helicopter Ditching
Authors: Faiella Edoardo , Grizzi Silvano , Passacantilli Fabio , Santic Ivan , Sellini Massimiliano 
Published: September 2024

Abstract
This paper presents the tracking method and results of the model tests of helicopter ditching, aimed at the study and certification of a helicopter for marine missions. The experiment, realized by Institute of Marine Engineering (CNR-INM), requires the design of a specific set-up to guarantee free ditching according to specific parameters and assuring the repeatability, required accuracy of the measurements and scalability of the results. Such kind of experiment is not a standard task of a hydrodynamic model testing institution, so it brings an innovation in the testing methodology. Tests were performed both in calm water both in regular wave conditions, main aim of the set-up is to synchronize the model free-fall with wave phase to ensure the correct water entry in specific wave positions. The paper presents the details of the test stand and the model itself, design of the experiment, as well as an overview of the results. The following figures shows some preliminary results of a wave-ditching parameters obtained with high-speed image tracking technique.
Non-invasive inspection methods for the defect analysis of filament wound composite cylinders and the process optimization
Authors: Chiominto Luciano , D’Emilia Giulio , Natale Emanuela , Stamopoulos Antonios 
Published: September 2024

Abstract
Filament winding is a manufacturing process used to produce cylindrical shapes pieces like pipes or pressure vessels for pressurized fluids, where high strength and stiffness are required. However, the manufacturing process often make the products susceptible to many defects, such as delaminations, voids, cracks, or fibre misalignments. The identification of these defects by non-destructive inspection methods is essential, also in the preliminary process optimization phase. This paper assesses some metrological characteristics of an ultrasonic inspection technique applied to composite filament wound cylinders. In particular, the ultrasonic technology is used to measure the thickness and determine the presence and the depth of gaps between layers, before and after a compression test. Interesting aspects about the uniformity of the fabrication are also looked at, useful for the production process optimization.
Characterisation of hydrophobic surfaces by droplet impact
Authors: Amoresano Amedeo , Roscioli Silvia 
Published: September 2024

Abstract
The paint industry constitutes a fundamental part of the entire industrial landscape. The primary role of paint is to preserve and protect a product from external sources such as weathering, vegetation, and rust. The maritime sector is particularly sensitive to this issue, as fouling on the hull can lead to a 40% increase in resistance, resulting in higher fuel consumption and the potential transportation of invasive species from one ecosystem to another. Paints used for ships have the characteristic of releasing biocides, primarily represented by copper and zinc, inhibiting life forms from adhering to the hull but at the same time causing a gradual “poisoning” of the ecosystem. For these reasons, new types of paints that exploit the principle of anti-adhesion rather than the release of biocides are being studied. This paper presents and characterizes epoxy-based surfaces with EPO-TQ, HDTMS, and PFOTES through experimental tests. Laboratory tests have highlighted the hydrophobicity level of each surface by evaluating the recovery time of a droplet impacting it and the final wetting angle. It has been demonstrated that among the three, the PFTOS surface exhibits the best performance and has the potential to be used as a surface/paint for naval vessels.
Flow field and acoustic assessment of twin rotors in hover conditions
Authors: De Gregorio F , Candeloro P , Ceglia G , Pagliaroli T 
Published: September 2024

Abstract
The paper presents part of the experimental activities in the GARTEUR Action Group RC/AG-26 framework to study the acoustic and aerodynamic characteristics of small rotors, including the influence of the rotor-rotor interactions. Two rotors with three-bladed propellers with a diameter D=393.7 mm were tested at a constant rotational speed of 5200 RPM, for different rotating verses and geometry configurations. Two rotor configurations were assessed in hover, i.e., either a baseline comprised of one isolated rotor, or two rotors arranged side-by-side. The aerodynamic loads, flow field velocity and acoustics emissions, were investigated using a six-component load cell, Particle Image Velocimetry and microphone array measurements, respectively. The aerodynamic characterisation of the isolated rotor was performed for a variety of rotating speeds. The interference between the slipstreams due to the side-by-side rotors was studied for co-rotating and counter-rotating verses at distances between the rotor axes of d=1.02D, d=1.1D, and 1.2D. The results showed that the slipstreams of the side-by-side rotors deflect and vary with the inter-axial distance. The rotor-rotor interaction, which is found to be related to the rotor distance, affects also the acoustic emissions. A remarkable loss of thrust is observed for the closest distance d=1.02D. Regarding acoustic emissions, the overall sound pressure level increases as the rotors run in counter-rotating verses compared to the co-rotating.
A review of source-sink association for enhancing yield of fruit vegetables
Authors: Tsan F Y , Reeza A A , Daud M F , Jaafar M Z , Nik Adli N M , Nur A’zam N N 
Published: September 2024

Abstract
Fruit vegetables are a component in a healthy diet. The dry weight gain and fruit production in fruit vegetables, being dependent on their photosynthetic activities, have been studied, and strategies that enhance fruit development have been discussed based on their source-sink associations. The efficiencies of the photosynthetic leaves and green colour herbaceous stems as the source capacity are critical in influencing the fruit load as fruits and seeds within them are plant parts that demand the photosynthetic product. This review paper discusses light intensity and quality, mineral metabolism, notably nitrogen balance, and leaf-to-fruit rationing that affect the leaf area index and net assimilation rate in crops. Manual leaf removal is among the husbandry practices that reduce the shaded leaves enabling the crops to utilize the resources in their environment more effectively. However, the studies on the source-sink relationship have been focused on a limited number of fruit vegetables, namely tomato and capsicum. This paper aims to gather some useful insights on source-sink manipulation on crops for future studies on many other fruit vegetables like cucurbits, okra etc. This paper also mentions the application of source-sink interaction models as a potential tool in predicting the economic yield of the fruit crops.
Economic efficiency of beef cattle farms in Peninsular Malaysia
Authors: Radzil R H M 
Published: September 2024

Abstract
Numbers of beef cattle farmers in Peninsular Malaysia were decreasing from 2016 to 2018 but there were increasing number of beef cattle farms on the years. Beef cattle farming is a costly business to operate locally because of its low performance, strong competitions with other high value agricultural activities, especially palm oil, cheaper prices of imported beef, and price elasticity that leads consumers towards other protein sources substitutes such as fish, poultry, mutton, and pork. The objective of the study is to measure the economic efficiency of beef cattle farms and identifying its determinants. Farm level data from 334 of beef cattle farmers collected in year 2020 were being analysed by Data Envelopment Analysis (DEA) for economic efficiency scoring. The determinants of the efficiency discovered using Tobit Model regression. The results show only 9.28 percent of the farms operate in the full economic efficiency while 44.31 percent of the firms were at the lowest range of economic efficiency score. The economic efficient farms depend on its financial aid, online networking, veterinary networking, job status, and the farm system. Government support by empowerment of smallholders through entrepreneurship skills were one of the suggestions for the industry to sustain economically. The research had justified the economic efficiency of beef cattle farms in Peninsular Malaysia with its determinants.
Using digital image correlation to evaluate fracture toughness and crack propagation in the mode I testing of concretes involving fly ash and synthetic nano-SiO2
Authors: Golewski Grzegorz Ludwik 
Published: September 2024

Abstract
This paper presents the experimental results and deep discussion on the simultaneous effect of fly ash (FA) and synthetic nano-SiO2 on the main strength parameters and fracture toughness expressed by critical stress intensity factor,

K

Ic

S

of a new concrete based on ternary blended cements (TC). Four series of concretes were made, one of which was the control concrete and the remaining three were TC. The effect of constant content of 5% nano-SiO2 and various FA contents such, i.e.: 0, 15 and 25% wt. as partial replacement of cement were studied. During the studies the DIC technique was applied to determine the deformation of the concrete beams in the propagation area of the modelled initial crack. Based on the studies it was found that the addition of 5% nano-SiO2 without FA increases the strength and fracture toughness of concrete by approx. 20%. On the other hand supplementing the composition of the binder with 5% nano-SiO2 in combination with the 15% FA additive causes an increase in all mechanical parameters by another approx. 20%. However, an increase in the FA content in the concrete mix by another 10% causes a smaller increase in the all analysed factors, i.e. by approx. 10% compared to composite with the addition of nano-SiO2 modifier only. In addition, based on the studies using DIC technique it was observed that in concrete including only nano-SiO2 the crack paths were almost perfectly rectilinear in shape, with a significant width of opening. However, in concrete containing 5% nano-SiO2 + 15% FA the crack paths were curvilinear with characteristic additional microcracks in the vicinity of the main crack, whereas in concrete with the addition of 5% nano-SiO2 + 25% FA the crack paths were very strongly curved and had pronounced branching and numerous additional microcracks in the vicinity of the main crack. From an application point of view, concretes involving FA and nano-SiO2 can be used in the execution of specific types of concrete and reinforced concrete structures that require a material with reduced brittleness and at the same time increased fracture toughness.
Fabrication, characterization, and in vitro studies of Selenium-substituted hydroxyapatite coatings
Authors: Zhang Chennan , Bai Yu , Li Ting , Li Jie , Gao Yuanming , Ma Wen 
Published: September 2024

Abstract
The increasing demand for hydroxyapatite (HA) coatings with enhanced functionality have led to novel materials with compositions that are more closely resembling those of natural bone apatites. In the present study, selenium-substituted (Se–HA) powders with various Se quantities were prepared by chemical precipitation. By applying suspension plasma spray (SPS), the surface of Ti substrates was coated with corresponding Se-HA coatings. The microstructural and physicochemical properties of the powders and the coatings were studied. Analysis by x-ray diffraction indicates that SeO3
2− replaced the PO4
3− groups, affecting the crystal structure and crystallinity of HA. As the extent of Se substitution increases, the lattice volume expands and the crystallinity decreases. The synthesized Se-HA powders were confirmed to be calcium-deficient apatite through energy-dispersive x-ray spectroscopy. However, the high temperature of SPS accelerated volatilization of P, increasing the Ca/(P + Se) ratio of the coatings, whereas the chemical valence state of Se remained unchanged. The Se–HA coating exhibited a high bonding strength of >33 MPa, fully meeting the requirement of 15 MPa as coating implant materials. Dissolution behavior tests indicate that the Se–HA coatings had high solubility in comparison to the HA coating. As the substitution degree of Se increased, the dissolution rate also increased, which greatly enhanced the capacity to generate a bone-like apatite layer. In vitro cell experiments indicate that the Se–HA coatings exhibited excellent biocompatibility, and facilitated adhesion and proliferation of osteoblast MC3T3-E1, even in the presence of fluorine. Furthermore, antibacterial properties of Se–HA coatings were also indicated by inhibition of Staphylococcus aureus, which is the main cause of most infections after orthopedic surgeries. Thus, the Se–HA coatings have potential as implant coating materials for orthopedic applications.
Green synthesis of Titanium dioxide nanoparticle using combination of plants and its antimicrobial study with their characterization
Authors: Ali Huma , Dixit Savita , Alarifi Saud 
Published: September 2024

Abstract
The characteristics and biological qualities of the nanomaterial rely heavily on how it was made. Green nanoparticle production has been developed to minimize pollution, cut expenses, and enhance safety for both human health and the environment by reducing metal ions using plant extracts as opposed to industrial chemical agents. The goal of the current work is to synthesize titanium dioxide nanoparticles in an environmentally friendly manner by using an extract from the combined shells of Stone apples (Aegle marmelos) and Wood apples (Limonia acidissima). Titanium dioxide nanoparticle formation was verified using various characterization techniques. Well diffusion was used to measure the antimicrobial activity. The fungal strains that were employed were Aspergillus Niger, Candida Albicans, and Aspergillus Flavus. All fungul strains were successfully inhibited by both the crudely prepared extract and the biosynthesized titanium dioxide nanoparticles; however, the biosynthesized titanium dioxide nanoparticles exhibited a high zone of inhibition ranging from 25 to 30 mm, while the crudely prepared extract had a low zone of inhibition ranging from 13 to 19 mm. A moderately sized zone of inhibition was observed in both the crude produced extract and the biosynthesized Titanium dioxide nanoparticles at a dilution of 100 μg ml−1. Lower dilutions demonstrated less noticeable inhibition. Overall, these results showed that treatment with biosynthesized titanium dioxide nanoparticles significantly slowed the growth of many microorganisms.
Effect of nanoparticles reinforcement of silicon dioxide derived from prosopis juliflora on Silver-Grey magnesium nanocomposite: utilization of silicon dioxide mechanical and tribological properties
Authors: Arundeep M , Suresh V , Srinivasnaik M , Yuvaraj K P 
Published: September 2024

Abstract
The automotive and aviation industries require lightweight materials to enhance working efficiency. Composites combine materials such as aluminium, magnesium, titanium, steel, and copper with various forms of reinforcements to offer lightweight alternatives for a range of applications. The present investigation aims to fabricate a Silver-Grey Magnesium (Mg-25%Si) alloy-based nanocomposite with silicon dioxide (SiO2) nano reinforcement at weight % of 0, 3.25, 6.5 and 9.75 utilizing the two step stir casting method. Prosopis juliflora is utilized in the production of different weight percentages of SiO2 nano reinforcements. The microhardness, tensile, wear, and impact tests are performed on the Silver-Grey Magnesium nanocomposites (Mg-25%Si/SiO2) utilizing a computerized tensometer testing machine, a Vicker’s hardness tester, a pin-on-disc tribometer, and an Izod impact, respectively. The x-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), and Energy-dispersive x-ray spectroscopy (EDAX) with elemental mapping microstructure were employed to scrutinize the tensile specimen fracture, EDAX, elemental mapping microstructure, wear, CoF, and worn surface characterization and impact strength analysis. When compared to the Silver-Grey Magnesium (Mg-25%Si) base alloy, the results of the Mg-25%Si/SiO2 nanocomposites demonstrated an increase in SiO2 nano reinforcements that significantly increased microhardness, tensile strength, wear resistance, and impact strength. The corresponding values are 113.36 VHN, yield and ultimate tensile strength of 603.25 MPa and 665.84 MPa, 0.00478 mm3 m−1, CoF of 0.38421 and 400 J m−1.
Life cycle assessment of electricity from wind, photovoltaic and biogas from maize in combination with area-specific energy yields – a case study for Germany
Authors: Böhm Jonas , Holzheid Fabian Michael , Schäfer Malte , Krexner Theresa 
Published: September 2024

Abstract
Due to the massive expansion of renewable energy-based production capacity, the benefits and drawbacks of wind turbines, ground-mounted photovoltaic (PV) and biogas plants are currently being discussed in Germany and elsewhere. The expansion of renewable energy-based plants is competing with other uses for land area. In addition to area-specific energy yields, the environmental impact of renewables is increasingly gaining awareness. Existing research on the area-specific energy yields and environmental impact for wind, PV and biogas lacks comparability due to factors including time, location, and scale. This study addresses this research gap by combining life cycle assessment (LCA) to compare potential environmental impacts with an area-specific energy yield assessment of wind, ground-mounted PV and biogas from maize in Germany. The LCA includes an assessment of eleven midpoint and three endpoint impact indicators, while the area-specific energy yield is assessed on the basis of both gross and net area-specific energy yield. The LCA results indicate the lowest impact for wind, followed by PV and biogas. This ranking is consistent across all three endpoint and nine out of eleven midpoint categories. The same ranking also applies to the area-specific energy yield, with wind producing the most and biogas the least gross and net energy per area. These results indicate that the current political support in Germany for biogas from maize for electricity generation should be thoroughly re-evaluated in view of the more favourable alternatives, wind and PV. The findings also provide relevant insights for other regions with similar boundary conditions.
Urban trees left high and dry – Modelling urban trees water supply and evapotranspiration under drought
Authors: Kluge Björn , Kirmaier Margit 
Published: September 2024

Abstract
Long-lasting extreme weather conditions are expected to occur more frequently in the future owing to climate change, as demonstrated by the recent heat waves. In particular, the decrease in precipitation during the summer months had a significant impact on urban tree water availability. Therefore, it is imperative to develop methodologies for determining the available water supply and evapotranspiration rates for urban trees. We mapped data from 49 urban small-leaved linden trees with varying characteristics including groundwater levels, shading situations, tree pit sizes, pavement materials, and sealing ratios. By combining these data with an adapted Penman-Monteith method to calculate evapotranspiration, we simulated the soil water storage and evapotranspiration rates of these trees during the very dry year of 2018 as an example. Model validations were performed using lysimeter and sap-flow studies on Tilia cordata trees in 2022. During the growing season, most trees experienced water stress on > 85% of the days because of weak precipitation events that failed to refill soil water storage. In contrast, trees with additional water supply through capillary rise reached water stress approximately 45 days later. The model results suggest that many trees will require additional water supply during predicted droughts in the future, which could have significant implications for urban forestry management. This model approach can be used to test and refine future water supply management strategies, making it a useful planning tool for improving the water efficiency of trees in urban areas and blue-green infrastructure.