bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptive tensegrity foot design for quadruped robots in unstructured terrains
Authors: Dong Hui , Gan Jiahao , Xia Rongbiao , Lu Zongxing , Chen Bingxing , Chen Muhao 
Published: December 2024

Abstract
Traditional quadruped robots are known for their agile movement and versatility across varied terrains. However, their foot structures struggle to navigate unstructured terrains such as pipes, slopes, and protrusions. This paper proposes a novel tensegrity foot structure consisting of a tensegrity ankle joint and an X-shaped adaptive tensegrity footpad, which enhances the terrain adaptability of legged robots. The equilibrium equation of the ankle joint is established, and the relationship between the translational stiffness of the ankle joint and the spring stiffness is derived. Additionally, a mathematical model for the number of X-shaped tensegrity footpad units and their relationship with the deformation height and length of the tensegrity footpad is established. A physical prototype of the tensegrity foot was fabricated using 3D printing. Experiments are conducted to validate the adaptability of both the ankle joint and the tensegrity footpad. The results indicate that the proposed adaptive tensegrity foot structure exhibits good adaptability on unstructured terrains with varying radii, slopes, steps, S-curves, and spherical surfaces. The tensegrity foot structure can enhance the environmental adaptability of quadruped robots and has excellent impact resistance effects.
Detailed varied-parameter characterization of the GaAs/AlxGa1–xAs super-multiperiod superlattices by photoreflectance spectroscopy
Authors: Khakhulin S A , Zakharchenko M V , Dashkov A S , Glinskii G F , Komkov O S , Pirogov E V , Sobolev M S , Goray L I , Bouravleuv A D 
Published: December 2024

Abstract
A room-temperature study of the optical transitions in GaAs/AlxGa1–xAs super-multiperiod superlattices (SMP-SLs) grown by molecular beam epitaxy was performed by photoreflectance spectroscopy. The development of devices based on high quality semiconductor SMP-SLs requires a comprehensive understanding of the energy miniband formation in the grown samples. Existing theoretical approaches to modeling the energy spectrum of SMP-SLs do not always correctly describe one in real structures due to the lack of correct information about the energy spectrum. The combination of the results of photoreflectance spectroscopy with the data obtained within the framework of the 8-band Kane theoretical model allows us to get a detailed interpretation of all optical transitions, that was confirmed by the results of the detailed study of GaAs/AlxGa1–xAs SMP-SL samples with different quantum wells and barriers widths.
Structure evolution, thermal stability and diffusion behaviors in Cu-Ta amorphous alloys studied by ab initio molecular dynamics simulation
Authors: Hao Ziyan , Wang Pengfei , Wu Yifan , Li Jianfeng , Zhang Pingxiang , Wang Yaocen , Cao Chongde 
Published: December 2024

Abstract
Cu-based materials consisting of immiscible elements have been paid much attention due to their high strength and high conductivity. The amorphous layers between Cu and strengthening phases formed through severe deformation play a crucial role in the improvement of properties. In this study, structure evolution, thermal stability of Cu100-xTax (x = 10, 30, 50, and 70 at.%) amorphous alloys and diffusion behaviors of alloys were studied by ab initio molecular dynamics (AIMD) simulations. With the Ta concentration rising, the number increase of Cu-Ta and Ta-Ta bonds results in the increase of volume for Cu-Ta amorphous alloys. Ta tends to be soluble in Cu clusters for Cu-rich amorphous alloys while Cu tends to be soluble in Ta clusters for relatively Ta-rich ones. According to energy evolution, the thermal stability of amorphous alloys decreases and then increases as Ta concentration increases. Compared with Cu element, the diffusion of Ta is significantly limited. The differences in thermal stability between Cu-Ta amorphous alloys and diffusion of Cu and Ta elements result in the formation of Ta-rich amorphous alloys after non-equilibrium fabricating. These results could substantively contribute to the development of Cu-based materials and understanding of the interface characteristic of immiscible alloys.
The effect of state preparation on the probe-bath parameters estimation
Authors: Mirza Ali Raza , Al-Khalili Jim 
Published: December 2024

Abstract
Projective measurement is a popular method of initial state preparation, which always prepares a pure state. However, in various physical situations of interest, this selective measurement becomes unrealistic. In this paper, we investigate the role of pulsed measurement (a unitary operation) on the estimation of system-environment parameters and compare the estimation results obtained via projective measurement with the results obtained via unitary operation. We argue that in typical situations, parameters can be estimated with higher accuracy if the initial state is prepared with the unitary operator (a pulse). We consider the spin-spin model in which a central two-level system (probe) interacts with a collection of two-level systems (bath). The probe interacts with the bath and attains thermal equilibrium. Then, via unitary operation, the initial state is prepared which evolves unitarily. The properties of the bath are imprinted on the reduced dynamics. Due to the initial probe-bath correlations present in the thermal equilibrium state, an additional factor arises in the dynamics, which has an important role in the parameter estimation. In this paper, we study the estimation of bath temperature and probe-bath coupling strength which is quantified by the quantum Fisher information. Our results are promising as one can improve the precision of the estimates by orders of magnitude (especially in the coupling strength case) via unitary operation and by incorporating the effect of initial correlations.
Silica modified by SiO2/silicone fluoroethylene acrylate emulsion superhydrophobic coating for electromagnetic wire study on the properties of the composite insulating layer
Authors: Xie Li , Peng Bo , Li Jun 
Published: December 2024

Abstract
In this paper, a silicone-containing fluoroethylene acrylate emulsion was synthesized through emulsion polymerization, and a superhydrophobic coating was prepared by compounding it with modified SiO2 particles. The micromorphology, composition, and hydrophobic properties of the coating surface were analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy, and water contact angle tests. The results revealed the presence of numerous micro-nanostructures on the coating surface, with a water contact angle of 161 ± 0.5°, indicating the characteristics of a superhydrophobic coating. A superhydrophobic composite insulating layer was created by modifying the quartz fiber insulating layer of electromagnetic wire with the superhydrophobic coating. The quartz fiber-insulated electromagnetic wire, treated with moisture, was evaluated for its insulation and breakdown voltage performance. The findings demonstrate that the superhydrophobic coating significantly reduces moisture absorption in quartz fiber, and the electromagnetic wire, even after moisture treatment, maintains excellent insulation and high breakdown strength, indicating promising applications in the field of electromagnetic wire insulation materials.
Observation and characterization of grain boundaries in monolayer MoSe2
Authors: Ma Hongliang , He Chang , Guo Zihao , Gao Qiang , Wang Xiaojing , Huang Yuan , Ding Jie , Zhang Wendong , Fan Xuge 
Published: December 2024

Abstract
Grain boundaries of MoSe2 impact their electrical, optoelectronic, and mechanical properties. The simple, efficient and rapid method to visualize the large-area grains and grain boundaries in MoSe2 is highly demanded but still lacking. Here, we show a simple, efficient, and rapid method for visualization of large-area grain boundaries in continuous CVD monolayer MoSe2 films that were transferred on a SiO2 substrate. As the monolayer MoSe2 was exposed to vapor hydrofluoric acid (VHF), the VHF diffused through grain boundary-based defects in the MoSe2 films and resulted in differential etching of the SiO2 at the MoSe2 grain boundaries and the SiO2 underneath the MoSe2 grains. The positions of the grain boundaries were prominent owing to the height difference of SiO2 and can be observed using optical microscopy, scanning electron microscopy, or Raman spectroscopy. This method would contribute to optimizing the growth process of MoSe2 and its device application.
2D MoS2 for detection of COVID-19 biomarkers – a first-principles study
Authors: Senthilkumar Surya Nagarathinam , Panjulingam Nandhini , Lakshmipathi Senthilkumar 
Published: December 2024

Abstract
This study investigates specific compounds in the breath that can indicate COVID-19 and lung cancer. Heptanal (C7H14O), acetone (C3H6O), propanol-1 (CH3CH2CH2OH), butanal (C3H7CHO), isopropanol (CH3CHOHCH3), acetaldehyde (CH3CHO), 2,4-octadiene (C8H14), and ethyl butyrate (C6H12O2) were studied. We analyze how these compounds interact using two-dimensional (2D) 2H and SV-MoS2 monolayers through first-principles calculations. Van der Waals forces bind all VOCs on the MoS2 surface in vacuum and humid conditions. The decrease in the band gap of the MoS2-VOC complex in these environments enhances sensitivity. The complexes of 2,4-octadiene, propanol-1, and ethyl butanoate are more conductive because their work function is lower, and their V(z) shift is more significant. The adsorption isotherm demonstrates the potential for surface reuse in sensing applications. The study confirms high sensitivity (>85%) and fast recovery time (up to 70 femtoseconds) for detecting in visible (VL) and ultraviolet (UV) regions. Mainly, 2,4-octadiene exhibits high sensitivity and selectivity. In conclusion, the 2H and SV MoS2 monolayers effectively detect COVID-19 and lung cancer markers in vacuum and humid conditions.
Effects of N/Ne impurity seeding on the divertor asymmetry in HL-2A tokamak
Authors: Tan Qingyi , Ye Haoran , Gong Xueyu , Zhong Yijun , Huang Qianhong , Wang Zhe , Cao Chengzhi , Wang Zhanhui , Fu Cailong , Xu Min , Yang Tao 
Published: December 2024

Abstract
Divertor asymmetry is a major challenge in achieving high-power, long-pulse discharges in future fusion reactors. Impurity seeding is the most common method for achieving divertor detachment in fusion devices. In this study, the SOLPS-ITER code is used to investigate the impact mechanisms of nitrogen (N) and neon (Ne) impurity seeding on the asymmetry between the inner and outer divertor in HL-2A under the attached and detached divertor conditions. Results indicate that N and Ne impurity seeding can increase asymmetry of energy and particle flux between the inner and outer targets. The trend in the energy flux ratio between the inner and outer targets is consistent with that of the particle flux ratio. Research indicates that under the attached divertor condition, the increase in energy flux asymmetry due to impurity seeding is primarily influenced by the electron temperatures between the inner and outer targets. However, when under the detached divertor condition, the increased asymmetry in energy and particle flux is primarily attributed to impurity seeding, which narrows the ion source generation in the inner divertor while broadening the ion sink region compared to the outer divertor.
Effects of white and red thyme oils against biofilm isolated from mineral plaster
Authors: Kobetičová K , Fišer A , Burianová I , Fraňková A 
Published: December 2024

Abstract
This study compared the effects of white and red thyme oil against natural biofilm. Thyme oil contains various volatile biologically active substances that can affect the growth of biofilm (algae, cyanobacteria, bacteria). In the first step, white thyme oil was therefore tested in flasks using a plastic lid (air-tight) or a cotton plug (air-permeable). The aim was to determine whether the method of closing the test containers affects the amount of biomass obtained. This was measured using a spectrometer at a wavelength of 750 nm. The results showed a clear positive effect of the cotton plug on the growth of the biofilm without a significant effect on the inhibition rate of the tested oil concentration. In the next step, the algicidal effectiveness of white and red thyme oil (10 mg/L and 100 mg/L) against biofilm was compared. The results showed a higher efficiency of red oil. Therefore, red thyme oil was selected for further research.
Cylindrical model of heat transfer in honeycomb structures with microencapsulated phase change material
Authors: Mihálka P , Slávik R , Čurpek J , Čekon M , Matiašovský P 
Published: December 2024

Abstract
The efficiency of a photovoltaic cell decreases with increased temperature. Excessive overheating caused by the absorption of incident solar radiation reduces the production of electricity. One of the ways to keep the panel cooler is to dissipate the heat from its backside. An aluminium honeycomb structure filled with microencapsulated phase change material (PCM) can dissipate enough heat to reduce overheating and improve the efficiency of the solar cell. Designing of Building’s Integrated Photovoltaic systems with PCM requires complex calculations considering wide variety of conditions. Finite element method (FEM) provides a robust tool, but this approach requires a very complex mesh domain due to the thin aluminium wall of the honeycomb structure, as well as iterative calculation process of boundary conditions accounting for complex convective and radiative heat transfer. Both require extensive computation time and FEM are not effective. The paper presents simplified cylindrical heat transfer model, which allows for faster computing with similar results. Comparison of compliance and computation times are included.
The use of light and scanning electron microscopy for the analysis of historical plasters
Authors: Böhm M , Krejsová J , Šál J , Javorský D , Všianský D 
Published: December 2024

Abstract
This paper presents the possibilities of using light microscopy (LM), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) to characterize historical lime-based plasters from the first half of the 20th century. The paper compares these methods and evaluates the advantages and limitations of each technique. The experiments carried out showed that, in addition to determining the elemental composition in specific layers and phases of the plaster, other important information can be analyzed by electron microscopy. It is also possible to identify admixtures or detect cracks, which is necessary to assess the effect of aging on the plaster and ensure its proper renovation.
Kaolin-based glass-ceramic glaze for cordierite based high-voltage insulators
Authors: Csáki Š , Žilinec M , Vozár L , Trník A 
Published: December 2024

Abstract
With the increase in the demand for electricity the improvement of the distribution system also starts to get special attention. Electricity is transferred over long distances; thus, the distribution related losses should be minimized. Conventional high-voltage alumina insulators have proven their efficiency over the past decades. To prevent the build-up of a conductive surface layer from dust and humidity, glazes are applied to these insulators. These glazes are amorphous, colored, and provide protection to the insulator body. The preparation glass-ceramic glazes requires mixing of initial laboratory grade materials and subsequent melting. However, kaolin contains several of the precursors needed for a preparation of cordierite glass-ceramics. Laboratory grade precursors were added to kaolin to obtain a composition close to that of cordierite. The mixtures prepared in the frame of the present paper exhibited good melting behavior (<1350°C), making them promising candidates to produce glass-ceramic glaze for high-voltage insulators.
Observation furnace for the monitoring of the melting process of glass-ceramic precursors
Authors: Žilinec M , Csáki Š , Ondruška J 
Published: December 2024

Abstract
Glass-ceramic glazes achieve better mechanical and electrical properties compared to the traditional glazes. Nevertheless, they have not been employed for the surface treatment of high-voltage insulators so far. For the production of glass-ceramic glaze, it is necessary to melt the precursor mixture, and then quickly cool it to form the so-called frits. Afterwards, the glass-ceramic glaze is prepared from the as-prepared frits. Therefore, it is important, that the chemical composition of frits is consistent with the chemical composition of the future glass-ceramic glaze. Moreover, in order to minimize the energy needed for the preparation of the frits, the melting of the raw materials needs to be studied and adjusted. A melting temperature not exceeding 1400 °C is desirable, as the firing temperature of the ceramic insulators is ∼1350 °C. This paper presents and describes the equipment used for the observation of the melting progress of ceramic samples during the thermal treatment.
The Characterization of Properties of Hard Historical Renders
Authors: Pokorný J , Fořt J , Šál J , Javorský D 
Published: December 2024

Abstract
Rendering materials combine two fundamental functions – create protective layers on a substrate and provide decorative and architectural appear of a building’s facade. In particular, many historical buildings are unique with their facades due to the incorporation of different decorative elements, such as plinths, lining cronies, reliefs etc. The composition of mortars used for renders contained many different components in view of binders and filler materials in the past. This fact in combination with conditions which are facades exhibited (weathering, increased moisture and others) effect their appear and overall durability. This paper is focused on the collection procedure of historical renders from two buildings located in the South bohemian region, and further the description and discussion of physical and mechanical properties of rendering materials samples are provided. These pilot data showed that one of examined buildings to some repairs were subjected historically, and for the second one partially different materials from the point of in their quality were used, although the outer facade layer (stucco) was uniform. The mapping of historical renders properties is essential for obtaining important data set for formulation of compatible composites intended for renovation interventions and local repairs.
A formula for the moisture diffusivity from a pore model
Authors: Medveď I , Černý R. 
Published: December 2024

Abstract
We derive an explicit formula for the moisture diffusivity of building porous materials using a general pore model that we proposed in a previous study. Since the model is applicable to a general pore curve, we apply it here to a pore curve that can be approximated by error function modified by an initial linear decrease. This is an extension of a case in which the linear decrease is neglected. To demonstrate the application of the results, we apply them to a simple unimodal pore curve measured for a fired ceramic brick.
The potential of using artificial intelligence in the processing of data measured by TDR for mass moisture conversion of porous building materials
Authors: Mikušová D , Suchorab Z , Trník A , Paśnikowska-Łukaszuk M 
Published: December 2024

Abstract
Accurate determination of moisture in buildings helps to prevent many problems, structural or health and hygiene. The Time Domain Reflectometry (TDR) technique can be used to determine moisture in buildings. This technique offers the possibility to perform measurements directly in the field without major destruction of the measured buildings. This technique is an indirect measurement technique, where the apparent permittivity of the environment is measured. To convert apparent permittivity into moisture content (volumetric or mass), empirical or physical models are used. Empirical models are developed specifically for the measured material and show greater accuracy than physical models. A prerequisite for the correct determination of moisture is a model with the greatest possible accuracy. This paper presents the possibility of using Machine Learning in the processing of data measured by TDR for volumetric water content. Machine Learning as a subdomain of Artificial Intelligence creates a mathematical model for predicting new data based on input and output data. This potential is precisely due to the model’s ability to learn from training data.
Controlling the fineness of synthesized tricalcium aluminate for cement addition
Authors: Scheinherrová L , Černá D , Šteffek M , Beneš M , Krejsová J 
Published: December 2024

Abstract
This paper presents a study on the laboratory synthesis of tricalcium aluminate (C3A) at temperatures ranging from 1300 to 1450 °C. The resulting C3A product exhibited variations in morphology, mineral composition, and hardness depending on the synthesis temperature. The primary objective of this research is to demonstrate methods for controlling the fineness of the synthesized C3A. Several approaches were employed and systematically compared. Additionally, a novel functional technique is proposed to achieve optimal particle size distribution curves, ensuring the suitability of C3A for cement applications.
The influence of 3D printing temperature on the impact strength of polylactide
Authors: Paśnikowska-Łukaszuk M , Urzędowski A , Szulżyk-Cieplak J , Wlazło M , Zaburko J 
Published: December 2024

Abstract
3D printing is one of the most developing technologies currently. There are many materials present on the market that allow you to get quite good and durable prints. One of the most commonly used materials is polylactide. The article presents the results of research on the influence of 3D stamping temperature on the impact strength of PLA filament using the Charpy test method. The paper presents the results of the impact strength of PLA samples as a function of printing temperature. In the paper compare samples printed at temperatures of 185 °C, 200 °C, and 210 °C. The highest moment of force was obtained for the 5th sample printed at a temperature of 185 °C, and the lowest for the 5th sample printed at a temperature of 200 °C, however, the values between subsequent measurements differ by a maximum of 0.11 [kpm].
Overview on the environmental impact of used engine oil
Authors: Armioni D M , Raţiu S A , Benea M L , Puţan V 
Published: December 2024

Abstract
The environmental impact of used engine oil encompasses multifaceted repercussions on soil, water, and air quality, constituting a significant concern in contemporary environmental discourse. This article provides a comprehensive overview of the harmful effects deriving from the improper disposal and leakage of used engine oil. Soil contamination occurs when toxic substances like heavy metals, polycyclic aromatic hydrocarbons (PAHs) and other hazardous substances are introduced into the soil, disrupting microbial communities, soil structure, and nutrient cycles. Concurrently, water bodies face contamination through runoff and direct discharge, leading to aquatic ecosystem disruption, bioaccumulation in aquatic organisms, and potential harm to human health. Furthermore, volatilization and incomplete combustion of used engine oil contribute to air pollution, releasing harmful gases and particulate matter, exacerbating respiratory ailments and contributing to global climate change. Mitigation strategies, including proper recycling, disposal protocols, and adoption of cleaner technologies, are imperative to alleviate the environmental burden posed by used engine oil. By synthesizing current research findings and highlighting the interconnectedness of soil, water, and air pollution, this article underscores the urgency for holistic approaches in addressing the environmental impact of used engine oil, emphasizing the imperative of sustainable practices to safeguard ecosystems and public health.