jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Johan Augusto Bocanegra | Federico Scarpa | Luca A. Tagliafico
Source: International Journal of Refrigeration (article, 2023-07-26)
Field: Materials Science — Electronic, Optical and Magnetic Materials

The role of external heat exchangers in the performance of active magnetic refrigerator The static performance of an Active Magnetic Regenerator Refrigerator (AMRR) can be evaluated using various indicators, such as the refrigeration capacity, coefficient of performance, and efficiency, for a given temperature span (that is, the hot-to-cold heat source temperature difference). The two main control parameters (cycle frequency and fluid mass flow rate) must be adjusted according to the imposed temperature span to achieve optimum performance. However, in real-world operations, heat exchangers at both ends of the regenerator thermally connect the device to the surroundings, and the hot and cold temperatures are no more imposed quantities. Under these heat transfer constraints, the device performance, in terms of refrigeration capacity, could be suboptimal, even after adjusting the two control parameters. Indeed, to provide optimal performance, heat exchangers must have precise values of the overall heat transfer coefficient, depending on the desired operating temperature difference. So, if a single pair of heat exchangers are used, it is impossible to characterize the performance of the magnetic refrigerator at different temperature spans. This work contrasts the systematic procedure for evaluating the performance of a magnetic refrigeration device with heat exchangers at the cold and hot ends to the procedure with an imposed temperature span. Both procedures can be used to obtain the optimal AMRR performance curves. However, this work highlights the necessity to use different (or variable heat transfer coefficient) heat exchangers when the first procedure is adopted. The needed overall heat transfer characteristic of both heat exchangers will be lower for a higher temperature span. Regenerative heat exchanger ; NTU method ; Refrigeration ; Refrigerator car ; Coefficient of performance ; Heat exchanger ; Heat transfer coefficient ; Heat transfer ; Work (physics) ; Plate fin heat exchanger ; Cooling capacity ; Thermodynamics ; Plate heat exchanger ; Micro heat exchanger ; Nuclear engineering ; Mechanics ; Materials science ; Mechanical engineering ; Engineering ; Heat pump ; Physics Magnetic and transport properties of perovskites and related materials ; Optical properties and cooling technologies in crystalline materials ; Advanced Thermodynamics and Statistical Mechanics
Authors: Aleksandr S. Tanichev | Д. В. Петров
Source: Molecules (article, 2023-04-11)
Field: Chemistry — Spectroscopy

Broadening of the ν2 Raman Band of CH4 by C3H8 and C4H10 Raman spectroscopy is a promising method for the analysis of natural gas. It is necessary to account for the broadening effects on spectral lines to improve measurement accuracy. In this study, the broadening coefficients for methane lines in the region of the ν<sub>2</sub> band perturbed by propane, n-butane, and isobutane at room temperature were measured. We estimated the measurement errors of the concentration of oxygen and carbon dioxide in the case of neglecting the broadening effects on the methane spectrum by the pressure of C<sub>2</sub>-C<sub>6</sub> alkanes. The obtained data are suited for the correct simulation of the methane spectrum in the hydrocarbon-bearing gases and can be used to improve the accuracy of the analysis of natural gas by Raman spectroscopy. Raman spectroscopy ; Propane ; Chemistry ; Materials science ; Computational chemistry ; Nuclear magnetic resonance ; Physics ; Optics ; Organic chemistry Spectroscopy and Laser Applications ; Molecular Spectroscopy and Structure ; Atmospheric Ozone and Climate
Authors: María Simón-Portela | José Ramón Villar-García | Desirée Rodríguez-Robles | Pablo Vidal-López
Source: Applied Sciences (article, 2023-05-06)
Field: Materials Science — Polymers and Plastics

Optimization of Glulam Regular Double-Tapered Beams for Agroforestry Constructions This paper addresses the lack of attention paid by the scientific community to the optimization of timber structures, specifically in the context of large-span agro-industrial constructions. The study focuses on the optimization of a three-dimensional roof composed of GL32h glulam regular double-tapered beams and purlins. Firstly, MATLAB was employed to develop a calculation software and then run the proposed optimization model based on genetic algorithms, in order to optimize the different geometries of the construction elements based on cost, as well as the optimum arrangement of the purlins and the number of beams. Moreover, statistical analyses were carried out on more than 200 optimization data points to uncover the influence of different variables in the optimization process. It was found that the snow load and span have a significant influence on the prediction of the height and width of beams and purlins, as well as the purlin spacing; while, as expected, the roof length also influences the optimal number of beams. All these findings could promote the use of timber structures; thus, achieving more sustainable and efficient construction practices. Structural engineering ; Roof ; MATLAB ; Computer science ; Genetic algorithm ; Span (engineering) ; Mathematical optimization ; Mathematics ; Engineering Textile materials and evaluations ; Tree Root and Stability Studies ; Forest Biomass Utilization and Management
Authors: Liu Shu | An-Tsun Wei | Hui Wang | David H. Van Winkle | Steven Lenhert
Source: Soft Matter (article, 2023-01-01)
Field: Chemistry — Spectroscopy

Combinatorial mixtures of organic solutes for improved liquid/liquid extraction of ions Biological systems routinely extract and organize ions in complex yet highly ordered and active systems. Much of this function is attributed to proteins, although recent evidence indicates aggregates of lipids are also capable of molecular recognition. Here we tested the hypothesis that combinatorial mixtures of organic solutes might lead to enhanced liquid/liquid extraction. We started with liquid oleic acid as an organic phase extracting copper ions from water and added a library of additives. By using Bayesian optimization to autonomously direct the combinatorial formulation, we discovered mixtures that enhanced the extraction performance. The main additive that improved the system was octylphosphonic acid. Interestingly, the optimal mixture has a significant improvement compared to this additive alone. This suggests that the combinations of organic solutes are better than using pure components in liquid/liquid extraction. Furthermore, we found that precipitation occurs in the samples showing better extraction efficiency, which has interesting material properties and potential for new types of supramolecular biosensors. Extraction (chemistry) ; Supramolecular chemistry ; Chemistry ; Ion ; Precipitation ; Chromatography ; Organic chemistry ; Molecule Mass Spectrometry Techniques and Applications ; Analytical Chemistry and Chromatography ; Molecular Junctions and Nanostructures
Authors: Zonglin Li | Pan Wang | Hongyu Zhao | Chengcheng Ao
Source: Thermal Science and Engineering Progress (article, 2023-09-01)
Field: Materials Science — Materials Chemistry

Multi-objective optimization study of hydrothermal aging on NOx-assisted soot catalytic combustion and secondary pollution emission in regeneration of CeO2 catalytic diesel particulate filter Soot ; NOx ; Diesel particulate filter ; Catalysis ; Diesel exhaust ; Combustion ; Chemical engineering ; Diesel fuel ; Catalytic combustion ; Hydrothermal circulation ; Chemistry ; Materials science ; Waste management ; Organic chemistry Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions ; Advanced Combustion Engine Technologies
Authors: Akimitsu Ishii | Akiyasu Yamamoto | Akinori Yamanaka
Source: Science and Technology of Advanced Materials Methods (article, 2023-07-20)
Field: Materials Science — Materials Chemistry

DMC-TPE: tree-structured Parzen estimator-based efficient data assimilation method for phase-field simulation of solid-state sintering In phase-field simulations, accurate material parameters are required to quantitatively predict microstructural evolutions. Non-sequential data assimilations enable the estimation of unknown material parameters by minimizing a cost function that represents the misfit between numerical simulation results and time-series observation data. In this study, a new non-sequential Data assimilation method Minimizing the Cost function using tree-structured Parzen estimator (TPE), namely DMC-TPE, with higher estimation accuracy than that of a conventional method (DMC-Bayesian optimization (BO)) is developed. The estimation accuracy of DMC-TPE is compared with that of DMC-BO via numerical experiments, where these methods are applied to a phase-field simulation of solid-state sintering. The comparison results demonstrate that the estimation accuracy of DMC-TPE is higher than that of DMC-BO, specifically in cases where numerous parameters have to be estimated, because TPE can continuously minimize the cost function by increasing the number of iterative minimization calculations. Furthermore, DMC-TPE provides less scatter in the estimation results than that in the case of DMC-BO. The DMC-TPE developed herein leads to highly accurate PF simulations of microstructural evolution by simultaneously estimating the states and many unknown material parameters with high accuracies based on experimental data. Estimator ; Data assimilation ; Algorithm ; Computer science ; Field (mathematics) ; Function (biology) ; Mathematical optimization ; Materials science ; Mathematics ; Statistics ; Physics Solidification and crystal growth phenomena ; Aluminum Alloy Microstructure Properties ; Metallurgical Processes and Thermodynamics
Authors: Donggeun Park | Jiyoung Jung | Seunghwa Ryu
Source: Composite Structures (article, 2023-05-11)
Field: Materials Science — Materials Chemistry

Double generative network (DGNet) pipeline for structure-property relation of digital composites Deep learning's fast and accurate inference between material configurations and properties has been used to design digital composites with superior mechanical properties. However, initial training sets cannot explore a vast design space with astronomical numbers of possible combinations, and most DL methods cannot guarantee predictive power in unobserved domains that may contain optimal configurations. Active learning-based gradual DNN model update schemes were implemented, but this increased computational costs. We propose a single-shot training pipeline to predict stress/strain distribution and stiffness over configuration space far from the initial training set. Predicting a composite's load response requires predicting its stress/strain field. Two autoencoders and a cGAN predict high-resolution stress/strain fields from grid-averaged local fields inferred from binary digital composite configurations. Our pipeline accurately predicts the high-resolution stress/strain field distribution in the unseen volume fraction (VF) domain or for composites with configurations very different from the initial training set. The framework can predict high-resolution fields in many physical phenomena and design composite materials for engineering applications . Pipeline (software) ; Computer science ; Stiffness ; Field (mathematics) ; Displacement field ; Structural engineering ; Artificial intelligence ; Mathematics ; Engineering ; Finite element method Machine Learning in Materials Science ; Composite Material Mechanics ; Injection Molding Process and Properties
Authors: Hilmiye Deniz Ertuğrul Uygun | Münire Nalan Demir
Source: Journal of the Turkish Chemical Society Section A Chemistry (article, 2023-11-11)
Field: Chemistry — Analytical Chemistry

The Role of Molecularly Imprinted Polymers In Sensor Technology: Electrochemical, Optical and Piezoelectric Sensor Applications With the help of molecular imprinting technology, artificial receptors can be made and used for identification. This technique's limitless application increases polymer technology and makes it adaptable to other technologies. In this study, examples of sensor applications are used to explain molecular imprinting technology (MIT) and its brief history. MIT can be used to create polymer-based artificial receptors with remarkable selectivity and affinity to detect any target molecules that can be imprinted on a polymer. A monomer is synthesized around a template molecule to create a selective cavity that serves as an artificial receptor. Molecularly imprinted polymers (MIP) offer a wide range of uses and have recently garnered much attention. These polymers' production methods, production kinds, and molecular imprinting techniques are all thoroughly detailed. The outstanding properties of MIPs make a crucial contribution to sensor applications offering selective, fast, easy, and cost-effective analysis, which became very popular after Clark published his first biosensor study. Apart from the biological recognition receptors, MIPs have the advantage that they are not affected by physical conditions of the environment, such as temperature, pH, and ion strength. To overcome the biological recognition receptors' disadvantages, molecularly imprinted polymers can be used for sensor development. From the point of view of the review, the combination of MIPs and sensors was explained and proposed as an informative paper. Molecularly imprinted polymer ; Molecular imprinting ; Molecular recognition ; Nanotechnology ; Polymer ; Materials science ; Biosensor ; Computer science ; Molecule ; Selectivity ; Chemistry ; Organic chemistry ; Catalysis Analytical chemistry methods development ; Advanced Chemical Sensor Technologies ; Electrochemical Analysis and Applications
Authors: Vitaly Gaydachuk | Andrii Kondratiev | А. М. Потапов
Source: Mechanics of Composite Materials (article, 2023-04-20)
Field: Materials Science — General Materials Science

Weight Optimization of Design Structural Parameters of Sandwich Composite Shells Shell (structure) ; Composite number ; Solid mechanics ; Specific strength ; Materials science ; Structural engineering ; Honeycomb ; Reinforcement ; Bearing capacity ; Computer science ; Composite material ; Engineering Material Properties and Applications ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry ; Structural mechanics and materials
Authors: Axel Groß
Source: ChemRxiv (preprint, 2023-05-19)
Field: Chemistry — Electrochemistry

Challenges for ab initio molecular dynamics simulations of electrochemical interfaces The modelling of electrochemical interfaces between a liquid electrolyte and an electrode from a quantum chemical perspective is typically done by performing ab initio molecular dynamics simulations. Thus the statistically nature of the electrolyte structure can be taken into account by performing the proper averages. However, in order to obtain reliable results for such electrochemical interfaces, the simulations should be performed for sufficiently large systems and sufficiently long times under potential control. These requirements lead to significant challenges for running such simulations which will be addressed in this contribution, together with possible approaches to address these challenges. Molecular dynamics ; Electrolyte ; Perspective (graphical) ; Ab initio ; Electrochemistry ; Chemical physics ; Electrode ; Computer science ; Statistical physics ; Quantum ; Computational chemistry ; Materials science ; Chemistry ; Physics ; Physical chemistry ; Quantum mechanics ; Artificial intelligence Electrochemical Analysis and Applications ; Spectroscopy and Quantum Chemical Studies ; Analytical Chemistry and Sensors
Authors: Hasnae Chfii | Amal Bouich | Andreu Andrio | Joeluis Cerutti Torres | Bernabé Marí Soucase | Pablo Palacios | Mohammed Abd Lefdil | Vicente Compañ
Source: Nanomaterials (article, 2023-08-11)
Field: Materials Science — Materials Chemistry

The Structural and Electrochemical Properties of CuCoO2 Crystalline Nanopowders and Thin Films: Conductivity Experimental Analysis and Insights from Density Functional Theory Calculations A novel manufacturing process is presented for producing nanopowders and thin films of CuCoO<sub>2</sub> (CCO) material. This process utilizes three cost-effective synthesis methods: hydrothermal, sol-gel, and solid-state reactions. The resulting delafossite CuCoO<sub>2</sub> samples were deposited onto transparent substrates through spray pyrolysis, forming innovative thin films with a nanocrystal powder structure. Prior to the transformation into thin films, CuCoO<sub>2</sub> powder was first produced using a low-cost approach. The precursors for both powders and thin films were deposited onto glass surfaces using a spray pyrolysis process, and their characteristics were examined through X-ray diffraction, scanning electron microscopy, HR-TEM, UV-visible spectrophotometry, and electrochemical impedance spectroscopy (EIS) analyses were conducted to determine the conductivity in the transversal direction of this groundbreaking material for solar cell applications. On the other hand, the sheet resistance of the samples was investigated using the four-probe method to obtain the sheet resistivity and then calculate the in-plane conductivity of the samples. We also investigated the aging characteristics of different precursors with varying durations. The functional properties of CuCoO<sub>2</sub> samples were explored by studying chelating agent and precursor solution aging periods using Density Functional Theory calculations (DFT). A complementary Density Functional Theory study was also performed in order to evaluate the electronic structure of this compound. Resuming, this study thoroughly discusses the synthesis of delafossite powders and their conversion into thin films, which hold potential as hole transport layers in transparent optoelectronic devices. Materials science ; Delafossite ; Thin film ; Dielectric spectroscopy ; Density functional theory ; Conductivity ; Chemical engineering ; Scanning electron microscope ; Nanotechnology ; Electrochemistry ; Composite material ; Oxide ; Metallurgy ; Physical chemistry ; Electrode ; Chemistry Copper-based nanomaterials and applications ; ZnO doping and properties ; Electronic and Structural Properties of Oxides
Authors: Xin Guo | Li Liu | Naixiu Ding | Guangye Liu
Source: Polymers (article, 2023-05-17)
Field: Materials Science — Materials Chemistry

Transformation from Electromagnetic Inflection to Absorption of Silicone Rubber and Accordion-Shaped Ti3C2MXene Composites by Highly Electric Conductive Multi-Walled Carbon Nanotubes Electromagnetic (EM) pollution becomes more penetrating in daily life and work due to more convenience provided by multi-electrical devices, as does secondary pollution caused by electromagnetic reflection. EM wave absorption material with less reflection is a good solution to absorb unavoidable EM radiation or reduce it from the source. Filled with two-dimensional Ti<sub>3</sub>SiC<sub>2</sub>MXenes, silicone rubber (SR)composite demonstrated a good electromagnetic shielding effectiveness of 20 dB in the X band by melt-mixing processes for good conductivity of more than 10<sup>-3</sup> S/cm and displayed dielectric properties and a low magnetic permeability; however, the reflection loss was only -4 dB. By the combination of one-dimensional highly electric conductive multi-walled carbon nanotubes (HEMWCNTs) and MXenes, the composites achieved the transformation from electromagnetic inflection to an excellent absorbing performance to reach a minimum reflection loss of -30.19 dB due to electric conductivity of above 10<sup>-4</sup> S/cm, a higher dielectric constant, and more loss in both dielectric and magnetic properties. Ni-added multi-walled carbon nanotubes were not able to achieve the transformation. The as-prepared SR/HEMWCNT/MXene composites have potential application prospects in protective layers, which can be used for electromagnetic wave absorption, electromagnetic interference suppression of devices, and stealth of the equipment. Composite material ; Materials science ; Silicone rubber ; Carbon nanotube ; Electrical conductor ; Carbon nanotube actuators ; Mechanical properties of carbon nanotubes ; Nanotube MXene and MAX Phase Materials ; 2D Materials and Applications ; Advanced Memory and Neural Computing
Authors: Dandan Guo | Muhammad Nadeem | Shuxin Yu | Jinhui Wang | Shaohua Huang | Yan Zhu
Source: Polymers (article, 2023-08-18)
Field: Chemistry — Inorganic Chemistry

Polyamidoamine Dendrimers Functionalized Water-Stable Metal–Organic Frameworks for Sensitive Fluorescent Detection of Heavy Metal Ions in Aqueous Solution In this work, polyamidoamine (PAMAM)-functionalized water-stable Al-based metal-organic frameworks (MIL-53(Al)-NH<sub>2</sub>) were proposed with enhanced fluorescence intensity, and used for the sensitive detection of heavy metal ions in aqueous solution. The size and morphology of MIL-53(Al)-NH<sub>2</sub> were effectively optimized by regulating the component of the reaction solvents. PAMAM dendrimers were subsequently grafted onto the surface with glutaraldehyde as a cross-linking agent. It was found that the size and morphology of MIL-53(Al)-NH<sub>2</sub> have great influence on their fluorescence properties, and PAMAM grafting could distinctly further improve their fluorescence intensity. With higher fluorescence intensity, the PAMAM-grafted MIL-53(Al)-NH<sub>2</sub> showed good linearity (R<sup>2</sup> = 0.9925-0.9990) and satisfactory sensitivity (LOD = 1.1-8.6 μmol) in heavy metal ions determination. Fluorescence enhancement and heavy metal ions detection mechanisms were discussed following the experimental results. Furthermore, analogous water-stable Materials of Institute Lavoisier (MIL) metal-organic frameworks such as MIL-53(Fe)-NH<sub>2</sub> were also proved to have similar fluorescence enhancement performance after PAMAM modification, which demonstrates the universality of the method and the great application prospects in the design of PAMAM-functionalized high-sensitivity fluorescence sensors. Fluorescence ; Metal ions in aqueous solution ; Dendrimer ; Aqueous solution ; Metal ; Materials science ; Glutaraldehyde ; Metal-organic framework ; Surface modification ; Inorganic chemistry ; Chemical engineering ; Chemistry ; Adsorption ; Polymer chemistry ; Organic chemistry ; Physical chemistry Metal-Organic Frameworks: Synthesis and Applications ; Dendrimers and Hyperbranched Polymers ; Molecular Sensors and Ion Detection