jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Huiping Fu | Ning Ding | Dan Ma | Qing Xu | Bingyong Lin | Bin Qiu | Zhenyu Lin | Longhua Guo
Source: Biosensors (article, 2022-12-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Green Synthesis of Three-Dimensional Au Nanorods@TiO2 Nanocomposites as Self-Cleaning SERS Substrate for Sensitive, Recyclable, and In Situ Sensing Environmental Pollutants In this work, a simple, low-cost, green, and mild method for the preparation of three-dimensional nanocomposite materials of gold nanorods (Au NRs)@TiO<sub>2</sub> is reported. The surface of Au NRs was coated with TiO<sub>2</sub> in situ reduction at room temperature without a complicated operation. The synthetic Au NRs@TiO<sub>2</sub> nanocomposites were used as surface-enhanced Raman spectroscopy (SERS) active substrates for the reusable and sensitive detection of environmental pollutants. The results showed that the pollutants on Au NRs@TiO<sub>2</sub> nanocomposites have higher SERS activity and reproducibility than those on the Au NR substrate without the presence of TiO<sub>2</sub>. Moreover, the SERS substrate can be readily recycled by UV-assisted self-cleaning to remove residual analyte molecules. Malachite green (MG) and crystal violet (CV) were used as examples to demonstrate the feasibility of the proposed sensor for the sensitive detection of environmental pollutants. The results showed that the limit of detections (LODs) were 0.75 μg/L and 0.50 μg/L for MG and CV, respectively, with the recoveries ranging from 86.67% to 91.20% and 83.70% to 89.00%. Meanwhile, the SERS substrate can be easily regenerated by UV light irradiation. Our investigation revealed that within three cycles, the Au NRs@TiO<sub>2</sub> substrates still maintained the high SERS enhancement effect that they showed when first used for SERS detection. These results indicated that the method can be used to detect MG and CV in really complex samples. Due to the high sensitivity, reusability, and portability and the rapid detection property of the proposed sensor, it can have potential applications in the on-site detection of environmental pollutants in a complex sample matrix. Malachite green ; Nanocomposite ; Nanorod ; Crystal violet ; Substrate (aquarium) ; Detection limit ; Surface-enhanced Raman spectroscopy ; Materials science ; Raman spectroscopy ; Pollutant ; Analyte ; Nanotechnology ; Nuclear chemistry ; Chemical engineering ; Chemistry ; Chromatography ; Raman scattering ; Adsorption ; Organic chemistry Gold and Silver Nanoparticles Synthesis and Applications ; Biosensors and Analytical Detection ; Electrochemical Analysis and Applications
Authors: D. Kumaravel | V.K. Bupesh Raja | Kabasker Balthaser | A. Jayaganthan | S. Sahas | S. Muralidharan | Tariku Achamyeleh
Source: Advances in Materials Science and Engineering (article, 2022-10-08)
Field: Materials Science — Metals and Alloys

Investigation on Wear and Corrosion Behavior of Cu, Zn, and Ni Coated Corten Steel Corten steel is a low-carbon alloy steel. It is widely used in architecture, the transport sector, and industrial applications, where the steel is exposed to harsh environments. It is very much sought after due to its auto protection from corrosive environments through the formation of patina (rust). The specialty of patina formed on the corten steel is that it can self-heal itself and stop the spreading of corrosion. Generally, steels are given protective coatings to enhance resistance to corrosion, wear, abrasion, etc. One of the popular protective coating techniques is electroplating. In this study, the effect of electroplating of copper (Cu), zinc (Zn), and nickel (Ni) on the wear and corrosion behavior of Corten ASTM A242 grade steel is investigated. It was observed that the Cu coating yielded poor corrosion and wear protection performance. The Zn coating exhibited a moderate improvement. The Ni electroplating produced excellent results and, the wear and corrosion resistance was improved in the corten steel. Thus, when compared with Cu, Zn, and Ni coatings, the Ni-coated corten steel is an ideal candidate in applications where there is a need for good resistance to wear, abrasion, and corrosion. Materials science ; Corrosion ; Metallurgy ; Electroplating ; Coating ; Abrasion (mechanical) ; Carbon steel ; Alloy ; Rust (programming language) ; Copper ; Zinc ; Wear resistance ; Layer (electronics) ; Composite material Hydrogen embrittlement and corrosion behaviors in metals ; Corrosion Behavior and Inhibition ; Microstructure and Mechanical Properties of Steels
Authors: Yu Harabuchi | Satoshi Maeda
Source: ChemRxiv (preprint, 2022-11-22)
Field: Chemistry — Organic Chemistry

Theoretical chemical reaction database construction based on quantum chemistry-aided retrosynthetic analysis A theoretical database comprising experimentally accessible and inaccessible chemical reactions could complement the existing experimental databases and contribute significantly to data-driven chemical reaction discovery. Quantum chemistry-aided retrosynthetic analysis (QCaRA) can generate a network of elementary steps called a reaction-path network and predict hundreds or more of chemical reactions along with their theoretical yields. In contrast to ordinary simulations, QCaRA traces back the reaction paths from the target product to various reactant candidates while solving the kinetic equations. In this study, we propose theoretical reaction database construction based on QCaRA. Seven reaction-path networks containing 13,190 reactions, 108,754 reaction paths, and 2,552,652 geometries have been identified and discussed as examples. In addition to well-known reactions (i.e., synthesis of fluoroglycine, Wöhler’s urea synthesis, base-catalysed aldol reaction, Lewis-acid-catalysed ene reaction, cobalt-catalysed hydroformylation, Strecker reaction, and Passerini reaction), numerous unexplored reactions with high, medium, low, near-zero, or zero yields have been identified. We anticipate that such a QCaRA-based theoretical reaction database will provide information on hitherto unexplored reactivities, especially those that are experimentally inaccessible. Retrosynthetic analysis ; Chemistry ; Aldol reaction ; Elementary reaction ; Chemical reaction ; Computational chemistry ; Database ; Reaction mechanism ; Combinatorial chemistry ; Computer science ; Organic chemistry ; Catalysis ; Total synthesis ; Physics ; Kinetics Radical Photochemical Reactions ; Computational Drug Discovery Methods ; Machine Learning in Materials Science
Authors: Pavel Nikitin | Ilya Zhukov | Dmitrii Tkachev | Yurii Abzaev | Екатерина Марченко | Alexander Vorozhtsov
Source: Materials (article, 2022-11-27)
Field: Materials Science — Materials Chemistry

Experimental and Theoretical Study of Ultra-Hard AlMgB14-TiB2 Composites: Structure, Hardness and Self-Lubricity It is known that the presence of oxygen phases in hard materials leads to an undesirable decrease in the mechanical properties. In materials based on AlMgB<sub>14</sub>, the main oxygen impurity is spinel MgAl<sub>2</sub>O<sub>4</sub>; it significantly reduces the hardness of AlMgB<sub>14</sub> and its formation during sintering is inevitable. In this work, the ultra-hard spark plasma sintered (SPSed) AlMgB<sub>14</sub>-TiB<sub>2</sub> composite material was fabricated from the AlMgB<sub>14</sub>-TiB<sub>2</sub> precursor obtained by self-propagating high-temperature synthesis (SHS). Due to the high synthesis temperatures, the main oxygen phase in the obtained composite was Al<sub>4</sub>B<sub>2</sub>O<sub>9</sub> instead of spinel MgAl<sub>2</sub>O<sub>4</sub>. It was found that the obtained composite has excellent mechanical properties. The maximum hardness of the sample is 44.1 GPa. The presence of oxygen in the form of the Al<sub>4</sub>B<sub>2</sub>O<sub>9</sub> phase led to unexpected results: the friction coefficient of the obtained AlMgB<sub>14</sub>-TiB<sub>2</sub> composite under dry conditions against the Al<sub>2</sub>O<sub>3</sub> counter-specimen is approximately four times lower than the friction coefficient of pure ceramic AlMgB<sub>14</sub> (0.18 against 0.7, respectively). Based on the observed results, it was found that the Al<sub>4</sub>B<sub>2</sub>O<sub>9</sub> particles formed during the SHS are responsible for the low friction coefficient. The quantum chemical calculations showed that the elastic moduli of Al<sub>4</sub>B<sub>2</sub>O<sub>9</sub> are significantly smaller than the elastic moduli of AlMgB<sub>14</sub> and TiB<sub>2</sub>. Thus, during sliding, Al<sub>4</sub>B<sub>2</sub>O<sub>9</sub> particles are squeezed out onto the composite surface, form the lubricating layer and reduce the friction coefficient. Materials science ; Spark plasma sintering ; Composite material ; Composite number ; Graphite ; Ceramic ; Phase (matter) ; Lubricity ; Elastic modulus Boron and Carbon Nanomaterials Research ; Metal and Thin Film Mechanics ; Advanced materials and composites
Authors: Manoj Kumar | Vijay Kumar | Vikramjeet Singh | Samridhi Thakral
Source: BMC Chemistry (article, 2022-11-24)
Field: Chemistry — Organic Chemistry

Synthesis, in silico studies and biological screening of (E)-2-(3-(substitutedstyryl)-5-(substitutedphenyl)-4,5-dihydropyrazol-1-yl)benzo[d]thiazole derivatives as an anti-oxidant, anti-inflammatory and antimicrobial agents A new series of (E)-2-(3-(substitutedstyryl)-5-(substitutedphenyl)-4,5-dihydropyrazol-1-yl)benzo[d]thiazole derivatives was synthesized and the chemical structures of synthesized compounds were deduced by IR and NMR spectral tools. These compounds were synthesized via aldol condensation reaction of substituted benzaldehydes and acetone in alkaline ethanolic solution and their in vitro anti-oxidant, anti-inflammatory and antimicrobial activities were investigated. All the synthesized compounds displayed anti-oxidant potential with IC<sub>50</sub> values ranging from 0.13 to 8.43 µmol/ml. The compound Z13 exhibited potent anti-inflammatory activity with IC<sub>50</sub> value of 0.03 µmol/ml compared with the standard ibuprofen, which showed IC<sub>50</sub> value of 0.11 µmol/ml. On the other hand, most of the compounds had a certain antibacterial potential particularly against P. aeruginosa and among these derivatives, compound Z2 exhibited the highest potential against P. aeruginosa with MIC value of 0.0069 µmol/ml. The analysis of docking results demonstrated the binding affinity and hydrogen bond, electrostatic and hydrophobic interactions of all the synthesized compounds with their respective targets. In silico ADMET studies were carried out for the synthesized compounds and most of the compounds exhibited good ADMET profile. Thiazole ; Chemistry ; Antimicrobial ; Ibuprofen ; Benzimidazole ; Docking (animal) ; Stereochemistry ; Combinatorial chemistry ; Proton NMR ; In vitro ; Aldol condensation ; Hydrogen bond ; Medicinal chemistry ; Nuclear chemistry ; Organic chemistry ; Molecule ; Biochemistry ; Catalysis Synthesis and biological activity ; Multicomponent Synthesis of Heterocycles ; Synthesis and Biological Evaluation
Authors: Deng Ying | Prasanna Pasam | Srinivas Addimulam | Vineel Mouli Natakam
Source: ABC Journal of Advanced Research (article, 2022-12-31)
Field: Materials Science — Polymers and Plastics

The Role of Polymer Blends in Enhancing the Properties of Recycled Rubber This research investigates the impact of polymer blends on strengthening the characteristics of recycled rubber, with a specific emphasis on enhancing mechanical strength, thermal stability, processability, and durability. The main goals are to assess the influence of different polymer blends on recycled rubber's performance and determine the advantages and drawbacks of these improvements. The study used a secondary data review process to evaluate enhancements in performance indicators such as tensile strength, elasticity, and heat resistance by analyzing previous research and case studies. The main discoveries indicate that combining polymers dramatically enhances mechanical characteristics, heat tolerance, and processing effectiveness, resulting in improved longevity and broader possibilities for using recycled rubber. Higher production costs and quality must be addressed. Environmental issues surround polymer additives. Policy implications include research and development, cost-effective and sustainable polymer production incentives, and regulatory frameworks to standardize processes and ensure environmental safety. Polymer mixing improves performance and sustainability, according to a study. These issues must be addressed by supporting legislation and encouraging the innovative use of recycled rubber. Natural rubber ; Materials science ; Polymer science ; Composite material ; Polymer blend ; Polymer ; Copolymer Natural Fiber Reinforced Composites ; Innovations in Concrete and Construction Materials ; Innovative concrete reinforcement materials
Authors: Kamil Wierzchowski | Mateusz Kawka | Michał Wrzecionek | Julia Urbanek | Agnieszka Pietrosiuk | Katarzyna Sykłowska-Baranek | Agnieszka Gadomska‐Gajadhur | Maciej Pilarek
Source: Plants (article, 2022-12-10)
Field: Materials Science — Biomaterials

Stress-Induced Intensification of Deoxyshikonin Production in Rindera graeca Hairy Root Cultures with Ester-Based Scaffolds In vitro plant cell and tissue culture systems allow for controlling a wide range of culture environmental factors selectively influencing biomass growth and the yield of secondary metabolites. Among the most efficient methods, complex supplementation of the culture medium with elicitors, precursors, and other functional substances may significantly enhance valuable metabolite productivity through a stress induction mechanism. In the search for novel techniques in plant experimental biotechnology, the goal of the study was to evaluate stress-inducing properties of novel biodegradable ester-based scaffolds made of poly(glycerol sebacate) (PGS) and poly(lactic acid) (PLA) influencing on the growth and deoxyshikonin productivity of <i>Rindera graeca</i> hairy roots immobilized on the experimental constructs. <i>Rindera graeca</i> hairy roots were maintained under the dark condition for 28 days in three independent systems, i.e., (i) non-immobilized biomass (a reference system), (ii) biomass immobilized on PGS scaffolds, and (iii) biomass immobilized on PLA scaffolds. The stress-inducing properties of the applied polymerized esters selectively impacted <i>R. graeca</i> hairy roots. The PGS scaffolds caused the production of deoxyshikonin, which does not occur in other culture systems, and PLA promoted biomass proliferation by doubling its increase compared to the reference system. Biomass (ecology) ; Chemistry ; Metabolite ; Secondary metabolite ; Glycerol ; Hairy root culture ; In vitro ; Cell culture ; Productivity ; Food science ; Biochemistry ; Biology ; Agrobacterium ; Agronomy biodegradable polymer synthesis and properties ; Graphene and Nanomaterials Applications ; Plant tissue culture and regeneration
Authors: Manoj Kumar Yadav | Mostafa H. Sliem | Aboubakr M. Abdullah | Khaled Youssef | Noora Al‐Qahtani
Source: Sustainability (article, 2022-06-30)
Field: Materials Science — Metals and Alloys

Impact of Prolonged Exposure to Sour Service on the Mechanical Properties and Corrosion Mechanism of NACE Carbon Steel Material Used in Wet Sour Gas Multiphase Pipeline The oil and gas industry is involved with severe corrosive/sour environmental conditions due to H2S, CO2, and moisture content. The National Association of Corrosion Engineers (NACE) has developed standards to enable users to select suitable materials for given sour conditions which utilize laboratory testing. A failed piping sample (API-5L-X65) was removed from a pipeline after 15 years of service. Optical microscopy was used to compare the microstructure of the corroded sample near the exposed surface to both the service environment, and further away from it. Moreover, pitted samples were analyzed using a scanning electron microscope coupled with energy dispersive X-ray (SEM/EDS) to understand the deposits’ morphology. Furthermore, XPS analysis proves the presence of a significant content of sulfur compound. Additionally, the mechanical properties of both corroded and non-corroded samples were evaluated and compared. Micro-hardness was carried out on the cross-section of the removed sample to understand any evident hardness variation from the inner diameter (ID) to the outer diameter (OD) of the piping. All the results suggest that prolonged service exposure has resulted in the development of micro defects, resulting in the reduction of strength and impact toughness, and the reduction in the hardness at the exposed surface of the corroded piping. Understanding the corrosion mechanism of pipelines exposed to sour media in the long-term helps in repair/replacement planning and extending the usable design life of the material, and paving the way for the oil and gas industry to develop additional ways to monitor the changes in the critical materials’ properties when exposed to sour service. Sour gas ; Corrosion ; Piping ; Metallurgy ; Materials science ; Service life ; Toughness ; Microstructure ; Scanning electron microscope ; Pipeline transport ; Welding ; Environmental science ; Composite material ; Natural gas ; Engineering ; Waste management ; Environmental engineering Hydrogen embrittlement and corrosion behaviors in metals ; Corrosion Behavior and Inhibition ; Material Properties and Failure Mechanisms
Authors: Jari Järvi | Milica Todorović | Patrick Rinke
Source: Physical review. B./Physical review. B (article, 2022-05-09)
Field: Materials Science — Materials Chemistry

Efficient modeling of organic adsorbates on oxygen-intercalated graphene on Ir(111) Organic charge transfer complexes (CTCs) can be grown as thin films on intercalated graphene (Gr). Deciphering their precise film morphologies requires global ab initio structure search, where configurational sampling is computationally intractable unless we reconsider the model for the complex substrate. In this study, we employ charged freestanding Gr to approximate an intercalated Gr/O/Ir(111) substrate, without altering the adsoption properties of deposited molecules. We compare different methods of charging Gr and select the most appropriate substitute model for Gr/O/Ir(111) that maintains the adsorption properties of fluorinated tetracyanoquinodimethane (${\mathrm{F}}_{4}\mathrm{TCNQ}$) and tetrathiafulvalene (TTF), prototypical electron acceptor/donor molecules in CTCs. Next, we apply our model in the Bayesian optimization structure search method and density-functional theory to identify the stable structures of ${\mathrm{F}}_{4}\mathrm{TCNQ}$ and TTF on supported Gr. We find that both molecules physisorb to Gr in various configurations. The narrow range of adsorption energies indicates that the molecules may diffuse easily on the surface and molecule-molecule interactions likely have a central role in film formation. Our study shows that complex intercalated substrates may be approximated with charged freestanding Gr, which can facilitate exhaustive structure search of CTCs. Tetrathiafulvalene ; Molecule ; Graphene ; Materials science ; Tetracyanoquinodimethane ; Adsorption ; Chemical physics ; Ab initio ; Density functional theory ; Acceptor ; Substrate (aquarium) ; Electron acceptor ; Computational chemistry ; Nanotechnology ; Physical chemistry ; Physics ; Chemistry ; Condensed matter physics ; Quantum mechanics ; Photochemistry Graphene research and applications ; Molecular Junctions and Nanostructures ; Quantum and electron transport phenomena
Authors: Wanli Li | Yue Luan | Qingyou Zhang | João Aires‐de‐Sousa
Source: Molecular Informatics (article, 2022-09-28)
Field: Materials Science — Materials Chemistry

Machine Learning to Predict Homolytic Dissociation Energies of C−H Bonds: Calibration of DFT‐based Models with Experimental Data Random Forest (RF) QSPR models were developed with a data set of homolytic bond dissociation energies (BDE) previously calculated by B3LYP/6-311++G(d,p)//DFTB for 2263 sp3C-H covalent bonds. The best set of attributes consisted in 114 descriptors of the carbon atom (counts of atom types in 5 spheres around the kernel atom and ring descriptors). The optimized model predicted the DFT-calculated BDE of an independent test set of 224 bonds with MAE=2.86 kcal/mol. A new data set of 409 bonds from the iBonD database (http://ibond.nankai.edu.cn) was predicted by the RF with a modest MAE (5.36 kcal/mol) but a relatively high R<sup>2</sup> (0.75) against experimental energies. A prediction scheme was explored that corrects the RF prediction with the average deviation observed for the k nearest neighbours (KNN) in an additional memory of experimental data. The corrected predictions achieved MAE=2.22 kcal/mol for an independent test set of 145 bonds and the corresponding experimental bond energies. Homolysis ; Dissociation (chemistry) ; Bond-dissociation energy ; Computational chemistry ; Calibration ; Chemistry ; Computer science ; Physical chemistry ; Physics ; Radical ; Organic chemistry ; Quantum mechanics Machine Learning in Materials Science ; Advanced Chemical Physics Studies ; Advanced NMR Techniques and Applications
Authors: Adam Olszewski | Paulina Kosmela | Adam Piasecki | Mateusz Barczewski | Aleksander Hejna
Source: Polymers (article, 2022-12-19)
Field: Materials Science — Polymers and Plastics

The Impact of Isocyanate Index and Filler Functionalities on the Performance of Flexible Foamed Polyurethane/Ground Tire Rubber Composites The structure and performance of polyurethane (PU) foams are strongly driven by the stoichiometry of the polyaddition reaction, quantitatively described by the isocyanate index. It determines the balance between isocyanate and hydroxyl groups in the reacting system and is affected by the introduction of additional functionalities originated, e.g., from applied fillers. Nevertheless, this issue is hardly taken into account in research works. Herein, the structure and performance of PU/ground tire rubber (GTR) composites differing in their isocyanate index (from 0.8 to 1.2) and prepared with and without considering the GTR functionalities in formulation development were investigated. Incorporating GTR into the PU matrix led to a reduction in average cell diameter (from 2 to 30% depending on the isocyanate index) compared to unfilled foams. However, formulation adjustments did not show a significant impact on cellular structure. The only decrease in open cell content was noted, from 10% for the 0.9 index to 40% for 1.2. Such changes were related to the increasing strength of the PU cellular structure able to maintain inside the increasing amount of carbon dioxide. On the other hand, considering hydroxyl values of GTR noticeably affected the thermomechanical performance of composites. The shift of glass transition temperature (T<sub>g</sub>), even by 10 °C for 1.2 isocyanate index, enhanced the performance of materials, which was expressed in an 8-62% drop in the composite performance factor, pointing to the enhanced reinforcing effect resulting from filler incorporation. The stiffening of foams, related to the variations in PU segmental structure, also caused minor changes in the course of thermal degradation of PU/GTR composites due to the inferior thermal stability of hard segments. The obtained results provide important insights into the development of formulations of PU composites filled with materials containing reactive functional groups able to disrupt the stoichiometric balance of the polyaddition reaction. Isocyanate ; Polyurethane ; Materials science ; Composite material ; Natural rubber ; Composite number ; Filler (materials) Polymer composites and self-healing ; Carbon dioxide utilization in catalysis ; biodegradable polymer synthesis and properties