jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Chiara Groppi | Federico Maspero | Andrea Rovelli | M. Asa | Gerardo Malavena | Christian Monzio Compagnoni | Edoardo Albisetti | S. Vangelista | Miguel Badillo | R. Bertacco
Source: Materials Science in Semiconductor Processing (article, 2023-02-28)
Field: Materials Science — Materials Chemistry

Electrode-dependent asymmetric conduction mechanisms in K0.5Na0.5NbO3 micro-capacitors The ultimate performance of devices employing lead-free piezoelectrics is determined not only by the intrinsic properties of the piezo, but also by processes and materials employed to create the electric contacts. In this paper, we investigate the impact of different metallic electrodes with increasing chemical reactivity (Pt, Ni, Ti, Cr), on the asymmetric behavior of the leakage current in M/K0.5Na0.5NbO3/Pt(111) micro-capacitors, where M stands for the top metallic electrode. For all electrodes we found a marked leakage asymmetry that we ascribed to the presence of a Schottky-like rectifying junction at the M/K0·5Na0·5NbO3/Pt(111) bottom interface, while the corresponding junction at the top interface is deeply affected by the creation of oxygen vacancies due to oxygen scavenging during the growth of the top metallic electrodes, leading to an almost ohmic top contact. The leakage increases with the reactivity of the electrodes, while the asymmetry decreases, thus suggesting that the creation of the top metal/K0·5Na0·5NbO3 interface generates oxygen vacancies diffusing down to the bottom interface and impacting on the rectifying behavior of the Schottky-like junction. Noteworthy, this asymmetric conduction can reflect in an asymmetric piezoelectric and ferroelectric behavior, as a sizable portion of the applied voltage drops across the rectifying junction in reverse bias, thus hampering symmetric bipolar operation, especially in leaky materials. Materials science ; Electrode ; Capacitor ; Ohmic contact ; Schottky barrier ; Ferroelectricity ; Schottky diode ; Thermal conduction ; Leakage (economics) ; Optoelectronics ; Piezoelectricity ; Asymmetry ; Voltage ; Nanotechnology ; Composite material ; Electrical engineering ; Dielectric ; Chemistry Ferroelectric and Piezoelectric Materials ; Advanced Memory and Neural Computing ; Electronic and Structural Properties of Oxides
Authors: John F. Barry | Matthew Steinecker | Scott T. Alsid | Jonah A. Majumder | Linh Pham | Michael F. O'Keefe | Danielle Braje
Source: arXiv (Cornell University) (preprint, 2023-05-10)
Field: Materials Science — Materials Chemistry

Sensitive AC and DC Magnetometry with Nitrogen-Vacancy Center Ensembles in Diamond Quantum sensing with solid-state spins offers the promise of high spatial resolution, bandwidth, and dynamic range at sensitivities comparable to more mature quantum sensing technologies, such as atomic vapor cells and superconducting devices. However, despite comparable theoretical sensitivity limits, the performance of bulk solid-state quantum sensors has so far lagged behind these more mature alternatives. A recent review~\cite{barry2020sensitivity} suggests several paths to improve performance of magnetometers employing nitrogen-vacancy defects in diamond, the most-studied solid-state quantum sensing platform. Implementing several suggested techniques, we demonstrate the most sensitive nitrogen-vacancy-based bulk magnetometer reported to date. Our approach combines tailored diamond growth to achieve low strain and long intrinsic dephasing times, the use of double-quantum Ramsey and Hahn echo magnetometry sequences for broadband and narrowband magnetometry respectively, and P1 driving to further extend dephasing time. Notably, the device does not include a flux concentrator, preserving the fixed response of the NVs to magnetic field. The magnetometer realizes a broadband \textcolor{mhsnew}{near-}DC sensitivity $\sim 460$~fT$\cdot$s$^{1/2}$ and a narrowband AC sensitivity $\sim 210$~fT$\cdot$s$^{1/2}$. We describe the experimental setup in detail and highlight potential paths for future improvement. Magnetometer ; Dephasing ; Narrowband ; Diamond ; Quantum sensor ; Physics ; Spins ; Vacancy defect ; Broadband ; Condensed matter physics ; Sensitivity (control systems) ; Quantum ; Magnetic field ; Materials science ; Optoelectronics ; Quantum computer ; Optics ; Quantum simulator ; Electronic engineering ; Quantum mechanics ; Engineering Diamond and Carbon-based Materials Research ; High-pressure geophysics and materials ; Electronic and Structural Properties of Oxides
Authors: Paul A. Johnson
Source: arXiv (Cornell University) (preprint, 2023-12-14)
Field: Chemistry — Spectroscopy

Richardson-Gaudin States This chapter gives an overview of Richardson-Gaudin states which represent weakly correlated pairs of electrons. They are parametrized by sets of numbers obtained from non-linear equations. The best method to solve these equations is presented in a straightforward manner with enough detail to implement the method computationally. Optimal expressions for the density matrix elements are discussed. A simple description of 1-dimensional hydrogen chains is presented in terms of Richardson-Gaudin states. Richardson-Gaudin states are placed in the larger context of integrable models and geminal wavefunctions of quantum chemistry. Geminal ; Wave function ; Simple (philosophy) ; Context (archaeology) ; Integrable system ; Matrix (chemical analysis) ; Physics ; Mathematical physics ; Quantum mechanics ; Theoretical physics ; Statistical physics ; Chemistry ; Stereochemistry ; Geology ; Philosophy Molecular spectroscopy and chirality
Authors: Eduard Muslimov | Damir Akhmetov | Danila Kharitonov | E. G. Ibatullin | N. K. Pavlycheva | V. Sasyuk | Sergey Golovkin
Source: Photonics (article, 2023-03-31)
Field: Materials Science — Surfaces, Coatings and Films

Optical Design of a Slitless Astronomical Spectrograph with a Composite Holographic Grism In the present work, we consider an optical design of a slitless spectrograph for an existing 0.5 m-class telescope. This design concept has a number of advantages such as compact size, simplicity, and simultaneous coverage of a large field of view. A challenge with this design is correcting aberrations caused by placing a dispersing element in a converging beam. To overcome this issue, we propose to use a composite grism, which represents a combination of a prism and a volume-phase holographic grating, the latter which is split into zones with independently optimized parameters. We demonstrate two designs of such a grism. In both designs, the spectrograph operates in the range of 450–950 nm in an F/6.8 beam and covers a field of view of 35.6′ × 7.2′. Through advanced modeling, it is shown that a composite grism having four rectangular zones with different thickness and index modulation depth of the hologram and recorded with an auxiliary deformable mirror decreases the astigmatic elongation by a factor of 85, increases the spectral resolving power by 4.4 times, and reaches R1389 while increasing the average diffraction efficiency by a factor of 1.31. If we reduce the number of zones to only two, replace the deformable mirror with two static corrector plates, and fix the hologram thickness, the corresponding performance gains still remain high: the astigmatism is reduced by a factor of 61, the spectral resolving power is up to 1.7 times higher, reaching R1067, and the efficiency is increased by a factor of 1.27. This shows that the proposed design allows the construction of a simple and compact instrument, providing high performance over the entire field of view and spectral range. Grism ; Optics ; Spectrograph ; Holography ; Grating ; Physics ; Diffraction efficiency ; Prism ; Telescope ; Reflector (photography) ; Galaxy ; Astrophysics ; Redshift ; Spectral line Optical Coatings and Gratings ; Adaptive optics and wavefront sensing ; Advanced optical system design
Authors: P. Anithakumari | S. Indhuja | M. Shareefa
Source: Journal of Plantation Crops (article, 2023-11-30)
Field: Chemistry — Inorganic Chemistry

Community farm school approach for coconut seedlings/juveniles through collaborative social actions Three Grama Panchayats in Kerala's Alappuzha district undertook community-level participatory action research in 2019–2021. A total of 90 coconut farmers participated in the adoption of ICAR-CPCRI technology to produce West Coast Tall (WCT) coconut seedlings that are resistant/tolerant to the root (wilt) disease at the community level. Partners included extension agents, coconut producers' societies (CPS) and clusters, women self-help groups (WSHGs), and agricultural labor organizations. The characteristics of technologies that are suggested for adoption in root (wilt) disease-aﬀected tracts, such as the scientific management of young coconut trees and the production of high-quality seedlings through community nurseries, challenge the idea of adoption. There are a lot of variances in the homestead gardens' marginal holdings, including expertise, the use of technology, and access to advisory services. Government agencies provided the majority of the seedlings and extension advisory services, emphasizing the necessity for FPO-based or private extension in the coconut growing industry. The coconut farmers' understanding has significantly improved as a result of the participatory interventions for managing seedlings. The participatory demonstration and community farm school (CFS) strategy is discussed in the paper as a way for homesteads to manage juvenile coconuts while integrating new ideas and fostering cross and reciprocal learning. Refining the current extension approach requires integrating new knowledge about the characteristics of seedling growth, future economic performance, and social evaluation of choices of technological, individual, and skill-oriented interventions in risk-prone areas with debilitating root (wilt) disease. Business ; Government (linguistics) ; Agricultural extension ; Citizen journalism ; Psychological intervention ; Agriculture ; Biology ; Political science ; Ecology ; Medicine Coconut Research and Applications
Authors: Yujie Zhu | Xinhua Dong | Shangshi Huang | Chuanyang Li | Rui Wang | Mingcong Yang | Shaojie Wang | Manxi Li | Zuodong Liang | Juan Li | Yaru Zhang | Qi Zhang | Hao Yuan | Qi Li | Jinliang He
Source: Applied Physics Letters (article, 2023-05-22)
Field: Materials Science — Polymers and Plastics

Prediction of mechanical properties for a grafted polypropylene system via transfer learning with a small database The increasing demand for polymer dielectrics in different scenarios, such as electrical insulation cable, requires elevated electrical and mechanical properties. In order to understand the relationship between mechanical properties and the structure of grafted monomers in a grafted polypropylene (PP) system, a design framework based on the transfer-learning method has been proposed for designing grafted side chain structure in PP system. 22 samples of polypropylene-grafted polymer are synthesized. Through a well-trained multi-layer perceptron model for predicting glass transition temperature (Tg), mechanical properties of the grafted PP have been well predicted by the transfer-learning method. Meanwhile, the grafting group structures are divided into nine substructures. By assembling these substructures, the chemical space is established for prediction. Moreover, candidates with satisfied deep traps and flexible mechanical properties are screened out for reference. This work turns qualitative understanding into a quantitative analysis based on mathematical models and broadens the application of polymer materials design with a small dataset. Polypropylene ; Materials science ; Polymer ; Perceptron ; Grafting ; Composite material ; Work (physics) ; Glass transition ; Computer science ; Mechanical engineering ; Artificial intelligence ; Artificial neural network ; Engineering Conducting polymers and applications ; Polymer Nanocomposites and Properties ; Polymer crystallization and properties
Authors: Aleena Rayamajhi | Md Sultan Mahmud
Source:  (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Detection and Segmentation of Anthracnose Leaf Spots in Flowering Dogwood Using Deep Learning for Site-Specific Management <b><sc>Abstract.</sc></b> Anthracnose is a serious fungal disease of dogwoods that reduces the aesthetic value of trees and causes crop loss in severe conditions. Chemical treatments and pruning are widely accepted management practices to mitigate anthracnose disease spread and minimize crop loss. This study aimed to develop an anthracnose disease detection and segmentation model to identify infected canopies in nurseries for site-specific management. A total of 262 RGB images acquired from anthracnose disease-infected trees were pre-processed; dataset was increased to 700 by augmentation, and annotation was performed using an annotation tool. A total of 500 annotated images were used to train a Mask R-CNN model that used transfer learning to develop the model's prediction capability. The validation was done using 100 annotated images, and testing was done using the remaining 100 unannotated images. The detection model results showed a precision value of 99.82%, a recall value of 92.21%, an F-1 score of 95.86% and had the potential to improve performance with a large dataset. This project establishes a baseline to develop a site-specific management system for dogwood to remove disease-infected canopies. Pruning ; Segmentation ; Annotation ; Artificial intelligence ; Spots ; Computer science ; Transfer of learning ; Precision and recall ; Canopy ; Deep learning ; RGB color model ; Pattern recognition (psychology) ; Machine learning ; Biology ; Horticulture ; Botany Wood and Agarwood Research ; Remote Sensing and LiDAR Applications ; Plant and Fungal Interactions Research
Authors: Ahmed S. Al‐Fatesh | Ahmed A. Ibrahim | Ahmed I. Osman | Fahad Albaqi | Rasheed Arasheed | F. Frusteri | Serena Todaro | Khalid Anojaidi | Mahmud S. Lanre | Ahmed E. Abasaeed | Anis H. Fakeeha | Abdulaziz Bentalib | Abdulaziz Bagabas
Source: Energy Science & Engineering (article, 2023-03-01)
Field: Materials Science — Materials Chemistry

Optimizing barium promoter for nickel catalyst supported on yttria‐stabilized zirconia in dry reforming of methane Abstract Barium doping effect on the activity and stability of nickel‐based catalysts, supported on yttria‐stabilized zirconia (Ni‐YZr), was investigated in dry reforming of methane. Catalysts were characterized by several techniques (nitrogen sorption, X‐ray diffraction [XRD], scanning electron microscopy with energy dispersive X‐ray, transmission electron microscopy [TEM], thermogravimetric analysis [TGA], temperature programmed oxidation, CO 2 ‐TPD, H 2 ‐TPR) and were tested in a fixed‐bed reactor at 800°C and 42,000 mL/h g cat . Barium played a crucial role in enhancing catalyst reducibility and CO 2 adsorption at high temperatures, as indicated by the activity and stability of the Ni‐YZr catalyst. The addition of 4.0 wt% of barium appeared to be the optimal loading, allowing for CH 4 conversion of 82%, which remained constant for 7 h of reaction, compared with 72% of barium‐unpromoted Ni‐YZr at 800°C. TEM images of the spent catalysts revealed the formation of multiwalled carbon nanotubes on all samples. The TGA analysis showed, however, that an increase in baria loading significantly reduced the coke formation amount, indicating the inhibition of coke formation and the enhancement of the catalytic activity. Such improvement in activity and stability was attributed to the incorporation of barium into YZr support, as revealed by XRD analysis, which inhibited the sintering of the catalysts support. Catalysis ; Thermogravimetric analysis ; Barium ; Cubic zirconia ; Materials science ; Coke ; Carbon dioxide reforming ; Sintering ; Scanning electron microscope ; Nickel ; Chemical engineering ; Yttria-stabilized zirconia ; Nuclear chemistry ; Inorganic chemistry ; Syngas ; Chemistry ; Metallurgy ; Ceramic ; Organic chemistry ; Composite material Catalytic Processes in Materials Science ; Catalysts for Methane Reforming ; Catalysis and Oxidation Reactions
Authors: Juan Du | Jialin Li | Chuan Wu | Qihang Zhang | Wen Pan | Jun Tang | Tianyu Zhao | Pinghuai Wang | Xiang Liu | Jiming Chen
Source: Crystals (article, 2023-06-07)
Field: Materials Science — Materials Chemistry

The Microstructural and Hardness Changes of Tungsten Fiber after Au2+ Irradiation Tungsten fiber-reinforced tungsten composite (Wf/W) material is considered a plasma-facing material (PFM) with good application prospects. Commercial tungsten wire (fiber) prepared through forging and drawing processes has excellent mechanical properties, as well as a very high recrystallization temperature due to the unique texture of it grain structure. Commercial tungsten fiber is the most proper reinforcement for Wf/W. The change in the properties of tungsten fiber because of neutron irradiation makes it inevitable for Wf/W to be used as PFMs. However, there is very little research on the change in the properties of tungsten fiber caused by neutron irradiation. In this work, we used heavy ion irradiation to simulate the displacement damage generated by neutron irradiation to explore the alteration of the properties of a commercial tungsten fiber caused by neutron irradiation. The investigated subject was tungsten fiber with a diameter of 300 μm. The irradiation source was 7.5 MeV Au2+, which generated a maximum displacement damage of 60 dpa at a depth of 400 nm, and the irradiation influenced depth was 1000 nm. Because of the irradiation, significant lattice distortion occurred within the tungsten fiber, resulting in the transition from (110) texture to (100) texture at the fiber’s cross-section. The results of the Schmidt factor and Taylor factor analysis indicate a decrease in the plasticity of the tungsten fiber after irradiation, but it did not completely lose its plasticity. The results of the nanoindentation test confirmed the radiation hardening. After irradiation, the hardness of the tungsten fiber increased by approximately 0.33 GPa, but this increase was relatively small compared to other tungsten-based materials. This indicates that commercial tungsten fiber is a low-cost and highly reliable reinforcement material for Wf/W composite materials. Tungsten ; Materials science ; Irradiation ; Composite material ; Fiber ; Nanoindentation ; Metallurgy ; Nuclear physics Fusion materials and technologies ; Advanced materials and composites ; Nuclear Materials and Properties
Authors: René García‐Contreras | Diego J. Celentano | Tengfei Luo | Zeyu Liu | J. O. Morales-Ferreiro
Source: Nanomaterials (article, 2023-01-12)
Field: Materials Science — Materials Chemistry

Phonon Dominated Thermal Transport in Metallic Niobium Diselenide from First Principles Calculations Niobium diselenide (NbSe<sub>2</sub>) is a layered transition metal dichalcogenide material which possesses unique electrical and superconducting properties for future nanodevices. While the superconducting, electrical, and bulk thermal transport properties of NbSe<sub>2</sub> have been widely studied, the in-plane thermal transport property of NbSe<sub>2</sub>, which is important for potential thermoelectric applications, has not been thoroughly investigated. In this report, we study the lattice in-plane thermal transport of 2D NbSe<sub>2</sub> by solving the phonon Boltzmann transport equation with the help of the first principles calculation. The thermal conductivity obtained at room temperature is 12.3 W/mK. A detailed analysis shows that the transverse acoustic phonon dominates the lattice thermal transport, and an anomalously small portion of electron contribution to the total thermal conductivity is observed for this metallic phase. The results agree well with experimental measurements and provide detailed mode-by-mode thermal conductivity contribution from different phonon modes. This study can provide useful information for integrating NbSe<sub>2</sub> in nanodevices where both electrical and thermal properties are critical, showing great potential for integrating monolayer NbSe<sub>2</sub> to thermoelectric devices. Phonon ; Thermal conductivity ; Condensed matter physics ; Materials science ; Superconductivity ; Thermoelectric effect ; Niobium ; Thermoelectric materials ; Boltzmann equation ; Seebeck coefficient ; Thermal ; Thermodynamics ; Physics ; Composite material Thermal properties of materials ; Advanced Thermoelectric Materials and Devices ; 2D Materials and Applications
Authors: Abdul Shakoor | Azhar Ul-Haq | Taosif Iqbal
Source:  (article, 2023-09-08)
Field: Materials Science — Electronic, Optical and Magnetic Materials

The Development and Evaluation of a High-Frequency Toroidal Transformer for Solid-State Transformer Applications The performance and efficiency of high-frequency transformers (HFTs) are significantly influenced by leakage inductance. To improve the efficiency of HFTs, it is crucial to consider the effects of leakage inductance during the design and analysis processes. This research study aims to investigate a high-frequency toroidal transformer by examining different magnetic materials (Ferrite, Amorphas, and Iron-Powdered Alloy), winding configurations (solid, twisted, and LITZ wire), and operating frequencies (10 kHz and 50 kHz). To validate the effectiveness of parametric optimization in enhancing the system efficiency, the designed toroidal HFT was constructed and tested in a 600/300 V 3 kW dual active bridge (DAB) converter. The leakage inductances were measured using a frequency sweeping LCR meter. Leakage inductance ; Transformer ; Inductance ; Toroid ; Electrical engineering ; Materials science ; Ferrite (magnet) ; Linear variable differential transformer ; Inductor ; Transformer types ; Energy efficient transformer ; Electromagnetic coil ; Electronic engineering ; Distribution transformer ; Engineering ; Physics ; Voltage ; Plasma Magnetic Properties and Applications ; Magnetic Field Sensors Techniques ; Magneto-Optical Properties and Applications
Authors: Biao Yang | Feiyun Peng | Ziqi Zhang | Zhaogang Wu | Hongbin Huang | Yuyi Shi | Zemin Han
Source: High Temperature Materials and Processes (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Multi-source microwave heating temperature uniformity study based on adaptive dynamic programming Abstract In view of the multi-physical field coupling and time-varying characteristics of the microwave heating medium process, how to dynamically plan the state characteristics of multiple microwave sources and optimize the material temperature uniformity becomes the focus of this article. To this end, first, algebraic graph theory is used to construct the multiple microwave sources as a multi-agent system, and a perfect communication topology is established to ensure the transfer and sharing of information. Second, according to the real-time temperature distribution of the material, an event-triggered adaptive dynamic planning algorithm is used to co-operate with the power input of the multiple microwave sources to ensure that no new hot spots are generated during the optimization of the temperature distribution using the self-organizing properties of the medium. Finally, a numerical calculation model for optimizing a mixture of integer and continuous variables is solved using the finite-element method. The experimental and numerical results show that this article improves the temperature uniformity by 32.4–73.5% and the heating efficiency by 14.3–39.4% compared to the generic heating model, and the feasibility of the method is verified by the different shapes of the heated material. Microwave ; Materials science ; Computer science ; Coupling (piping) ; Finite element method ; Heat transfer ; Process (computing) ; Topology (electrical circuits) ; Field (mathematics) ; Mathematical optimization ; Algorithm ; Process engineering ; Mechanical engineering ; Mechanics ; Structural engineering ; Mathematics Microwave-Assisted Synthesis and Applications