jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Donghwi Kim | Youngjae Ryu | Ju-Heon Lee | Sung Woon
Source: Polymers (article, 2021-08-30)
Field: Materials Science — Polymers and Plastics

Effect of Aluminum Flakes on Mechanical and Optical Properties of Foam Injection Molded Parts Injection research using aluminum flakes has been conducted to realize metallic textures on the surface of plastic products. Several studies have focused on the effect of the orientation and quality of the flakes when using conventional injection molding methods; however, limited studies have focused on the foam injection molding method. In this study, we examined the orientation of aluminum flakes through foam injection with an inert gas and observed the changes in texture using a spectrophotometer and a gloss meter. The mechanical properties were also studied because the rigidity of the product, which is affected by the weight reduction that occurs during foaming, is an important factor. The results demonstrate that under foam injection molding, reflectance and gloss increased by 6% and 7 GU, respectively, compared to those obtained using conventional injection molding; furthermore, impact strength and flexural modulus increased by 62% and 15%, respectively. The results of this research can be applied to incorporate esthetic improvements to products and to develop functional parts. Gloss (optics) ; Materials science ; Composite material ; Molding (decorative) ; Inert ; Flexural rigidity ; Blowing agent ; Izod impact strength test ; Injection moulding ; Flexural strength ; Polyurethane ; Ultimate tensile strength ; Coating Polymer Foaming and Composites ; Injection Molding Process and Properties ; Additive Manufacturing and 3D Printing Technologies
Authors: Oluwaseyi Ayodele Ajibade | Johnson Olumuyiwa Agunsoye | Sunday Ayoola Oke
Source: Journal of Applied Science & Process Engineering (article, 2021-04-30)
Field: Materials Science — Polymers and Plastics

Taguchi Method and Taguchi-Pareto Scheme to Evaluate Diffusivity during the Development of Orange Peel Epoxy Composites The diffusion parameters of orange peel epoxy composites are important elements in composite structure in that they explain how fast water and other fluids can diffuse through the composites as a sign of integrity test. In this article, we defined the optimal parametric settings for diffusivity parameters of orange peel epoxy composites. The Taguchi optimisation method used obtained an optimal parametric setting of P4Q4R1 in experiments conducted for three and seven days, respectively. The analysis of variance revealed significant contributions made by the initial and final weights, while the thickness parameter was found to be less significant. A variant of the Taguchi method called Taguchi-Pareto was introduced, which also underscores the thickness parameter as not economical to optimality. The specifications and dimensions obtained by Taguchi method or its variant may be useful design engineers when contemplating on how to reduce diffusivity and water uptake of composites. Taguchi methods ; Epoxy ; Materials science ; Orthogonal array ; Composite material ; Composite number ; Thermal diffusivity ; Parametric statistics ; Pareto principle ; Computer science ; Mathematics ; Mathematical optimization ; Statistics ; Thermodynamics ; Physics Natural Fiber Reinforced Composites ; Textile materials and evaluations ; Acoustic Wave Phenomena Research
Authors: K. A. Nekrasov | А. Е. Галашев | D. D. Seitov | Sanjeev K. Gupta
Source: Chimica Techno Acta (article, 2021-03-31)
Field: Materials Science — Materials Chemistry

Diffusion of oxygen in hypostoichiometric uranium dioxide nanocrystals. A molecular dynamics simulation A molecular dynamic simulation of diffusion of intrinsic oxygen anions in the bulk of hypostoichiometric UO2-x nanocrystals with a free surface was carried out. The main diffusion mechanism turned out to be the migration of oxygen by the anionic vacancies. It is shown that in the range of values of the non-stoichiometry parameter 0.05 £x £ 0.275 the oxygen diffusion coefficient D is weakly dependent on temperature, despite the uniform distribution of the vacancies over the model crystallite. The reliable D values calculated for the temperature T = 923 K are in the range from 3×10-9 to 7×10-8 cm2/s, in quantitative agreement with the experimental data. The corresponding diffusion activation energy is in the range from 0.57 eV to 0.65 eV, depending on the interaction potentials used for the calculations. Diffusion ; Molecular dynamics ; Oxygen ; Uranium dioxide ; Stoichiometry ; Nanocrystal ; Crystallite ; Activation energy ; Chemical physics ; Atmospheric temperature range ; Materials science ; Self-diffusion ; Effective diffusion coefficient ; Range (aeronautics) ; Chemistry ; Analytical Chemistry (journal) ; Physical chemistry ; Thermodynamics ; Crystallography ; Nanotechnology ; Uranium ; Computational chemistry ; Physics Nuclear Materials and Properties ; Molten salt chemistry and electrochemical processes ; Radioactive element chemistry and processing
Authors: Dinh-Trinh Tran | Thi-My-Trinh Ha | Thi-An-Hang Nguyen | Viet-Cuong Dang | Van‐Duong Dao
Source: Research Square (preprint, 2021-10-01)
Field: Materials Science — Materials Chemistry

Facile Techniques to Synthesize Reduced Graphene Oxide for Removing Tetracycline From Water: Kinetics and Thermodynamics Studies Graphene ; Kinetics ; Oxide ; Thermodynamics ; Materials science ; Chemistry ; Tetracycline ; Nanotechnology ; Physics ; Organic chemistry ; Biochemistry ; Antibiotics Graphene research and applications ; Nanomaterials for catalytic reactions ; Graphene and Nanomaterials Applications
Authors: Lauren T. W. Fey | Anne Marie Z. Tan | Thomas D. Swinburne | Danny Pérez | Dallas R. Trinkle
Source: Physical Review Materials (article, 2021-08-09)
Field: Materials Science — Materials Chemistry

Accelerated molecular dynamics simulations of dislocation climb in nickel The mechanical behavior of materials operating under high temperatures is strongly influenced by creep mechanisms such as dislocation climb, which is controlled by the diffusion of vacancies. However, atomistic simulations of these mechanisms have traditionally been impractical due to the long time scales required. To overcome these time scale challenges, we use Parallel Trajectory Splicing (ParSplice), an accelerated molecular dynamics method, to simulate dislocation climb in nickel. We focus on modeling the activity of a vacancy near a jog on an edge dislocation in order to observe vacancy pipe diffusion and vacancy absorption at the jog. From rigorously constructed trajectories encompassing more than 2000 vacancy absorption events over a simulation time of more than $4\phantom{\rule{0.222222em}{0ex}}\ensuremath{\mu}\mathrm{s}$ at 900 K, a comprehensive sampling of available atomistic mechanisms is collated and analyzed further with molecular statics calculations. We estimate average rates for pipe diffusion and vacancy absorption into the jog using data from the dynamic and static calculations, finding very good agreement. Our results strongly suggest that the dominant mechanism for vacancy absorption by jogs is via biased diffusion to the dislocation core followed by fast pipe diffusion to the jog. Climb ; Vacancy defect ; Dislocation ; Materials science ; Diffusion ; Molecular dynamics ; Condensed matter physics ; Absorption (acoustics) ; Crystallography ; Physics ; Thermodynamics ; Computational chemistry ; Chemistry ; Composite material Microstructure and mechanical properties ; High Temperature Alloys and Creep ; Advanced Materials Characterization Techniques
Authors: Chao Liu | Xin Wang | Ge Zhou | Feng Li | Siqian Zhang | Haoyu Zhang | Lijia Chen | Haijian Liu
Source: Frontiers in Materials (article, 2021-01-14)
Field: Materials Science — Materials Chemistry

Dislocation-Controlled Low-Temperature Superplastic Deformation of Ti-6Al-4V Alloy The superplastic tension and deformation mechanism of Ti-6Al-4V alloy at 923 K and a tensile speed of 10 −3 , 5 × 10 −3 , or 5 × 10 −2 s −1 was studied on an AG 250KNE electronic tension tester. Through theoretical modeling, the unit dislocation count of this alloy during superplastic deformation was introduced into the Ruano–Wadsworth–Sherby (R-W-S) deformation mechanism map, and a new deformation mechanism map involving dislocation count was plotted. Thereby, the mechanism underling the low-temperature superplastic deformation of this alloy was predicted. It was found the superplastic tension of Ti-6Al-4V at the tested temperature was controlled by dislocation movement, and with an increase in strain rate, the deformation transited from the dislocation-controlled mechanism with a stress index of 4 to the dislocation glide mechanism with a stress index of 5 or 7. At the strain rate of 10 −3 s −1 , this alloy reached the largest tension rate of 790% and strain rate sensitivity index of 0.52 and had excellent low-temperature superplastic properties. Superplasticity ; Materials science ; Deformation mechanism ; Deformation (meteorology) ; Dislocation ; Strain rate ; Alloy ; Metallurgy ; Dislocation creep ; Composite material ; Stress (linguistics) ; Tension (geology) ; Ultimate tensile strength ; Microstructure Titanium Alloys Microstructure and Properties ; Microstructure and mechanical properties ; Advanced materials and composites
Authors: Fuxing Yin | Ming Ming Su | Fa Ji | Qingchao Tian | Bai Yaguan | Jianhang Feng | Zhixia Xiao
Source: China Foundry (article, 2021-05-01)
Field: Materials Science — Materials Chemistry

Effect of melting rate on microsegregation and primary MC carbides in M2 high-speed steel during electroslag remelting Large-size primary MC carbides can significantly reduce the performance of M2 high-speed steel. To better control the morphology and size of primary MC carbides, the effect of melting rate on microsegregation and primary MC carbides of M2 steel during electroslag remelting was investigated. When the melting rate is decreased from 2 kg·min−1 to 0.8 kg·min−1, the columnar dendrites are gradually coarsened, and the extent of segregation of Mo and V is alleviated, while the segregation of Cr becomes severe. At 2 kg·min−1, the number of primary MC carbides per unit area with the sizes in the range of 2 µm to 6 µm accounts for about 75% of all MC carbides, while the carbides are mainly concentrated on the size larger than 8 µm at 0.8 kg·min−1. Thermodynamic calculations based on the Clyne-Kurz (simplified to C-K) model shows that MC carbide can be precipitated in the final solidification stage and a smaller secondary dendrite arm spacing caused by higher melting rate (2 kg·min−1 in this experiment) facilitates the refinement of primary MC carbides. Carbide ; Materials science ; Metallurgy ; Dendrite (mathematics) ; Melting temperature ; High-speed steel ; Composite material ; Geometry Metal Alloys Wear and Properties ; Advanced materials and composites ; Microstructure and Mechanical Properties of Steels
Authors: Matthew R. Stites
Source: Digital Commons - USU (Utah State University) (article, 2021-09-30)
Field: Chemistry — Analytical Chemistry

Assessing and Enabling Independent Component Analysis As A Hyperspectral Unmixing Approach As a result of its capacity for material discrimination, hyperspectral imaging has been utilized for applications ranging from mining to agriculture to planetary exploration. One of the most common methods of exploiting hyperspectral images is spectral unmixing, which is used to discriminate and locate the various types of materials that are present in the scene. When this processing is done without the aid of a reference library of material spectra, the problem is called blind or unsupervised spectral unmixing. Independent component analysis (ICA) is a blind source separation approach that operates by finding outputs, called independent components, that are statistically independent. ICA has been applied to the unsupervised spectral unmixing problem, producing intriguing, if somewhat unsatisfying results. This dissatisfaction stems from the fact that independent components are subject to a scale ambiguity which must be resolved before they can be used effectively in the context of the spectral unmixing problem. In this dissertation, ICA is explored as a spectral unmixing approach. Various processing steps that are common in many ICA algorithms are examined to assess their impact on spectral unmixing results. Synthetically-generated but physically-realistic data are used to allow the assessment to be quantitative rather than qualitative only. Additionally, two algorithms, class-based abundance rescaling (CBAR) and extended class-based abundance rescaling (CBAR-X), are introduced to enable accurate rescaling of independent components. Experimental results demonstrate the improved rescaling accuracy provided by the CBAR and CBAR-X algorithms, as well as the general viability of ICA as a spectral unmixing approach. Hyperspectral imaging ; Component (thermodynamics) ; Independent component analysis ; Computer science ; Remote sensing ; Environmental science ; Artificial intelligence ; Geography Spectroscopy and Chemometric Analyses ; Remote-Sensing Image Classification ; Geochemistry and Geologic Mapping
Authors: Vilija Kederienė | Indrė Jaglinskaitė | Paulina Voznikaitė | Jolanta Rousseau | Patrick Rollin | Algirdas Šačkus | Arnaud Tatibouët
Source: Molecules (article, 2021-11-11)
Field: Chemistry — Organic Chemistry

Mild Copper-Catalyzed, l-Proline-Promoted Cross-Coupling of Methyl 3-Amino-1-benzothiophene-2-carboxylate Cu-catalyzed <i>N</i>-arylation is a useful tool for the chemical modification of aromatic heterocycles. Herein, an efficient carbon-nitrogen cross-coupling of methyl 3-amino-1-benzothiophene-2-carboxylate with a range of (hetero)aryl iodides using CuI, l-proline and Cs<sub>2</sub>CO<sub>3</sub> in dioxane at moderate temperature is described. The procedure is an extremely general, relatively cheap, and experimentally simple way to afford the <i>N</i>-substituted products in moderate to high yields. The structures of the new heterocyclic compounds were confirmed by NMR spectroscopy and HRMS investigation. Benzothiophene ; Chemistry ; Catalysis ; Proline ; Aryl ; Carboxylate ; Organic chemistry ; Copper ; Nuclear magnetic resonance spectroscopy ; Nitrogen ; Combinatorial chemistry ; Amino acid Catalytic Cross-Coupling Reactions ; Catalytic C–H Functionalization Methods ; Nanomaterials for catalytic reactions
Authors: Jianguo Liu | Mingyue Zhang | Longlong Ma
Source: Catalysts (article, 2021-02-22)
Field: Materials Science — Materials Chemistry

Facile Synthesis of COF-Supported Reduced Pd-Based Catalyst for One-Pot Reductive Amination of Aldehydes Dibenzylamine motifs are an important class of crucial organic compounds and are widely used in fine chemical and pharmaceutical industries. The development of the efficient, economical, and environmentally friendly synthesis of amines using transition metal-based heterogeneous catalysts remains both desirable and challenging. Herein, we prepared the covalent organic framework (COF)-supported heterogeneous reduced COF-supported Pd-based catalyst and used it for the one-pot reductive amination of aldehydes. There are both Pd metallic state and oxidated Pdσ+ in the catalysts. Furthermore, in the presence of the reduced COF-supported Pd-based catalyst, many aromatic, aliphatic, and heterocyclic aldehydes with various functional groups substituted were converted to their corresponding amines products in good to excellent selectivity (up to 91%) under mild reaction conditions (70 °C, 2 h, NH3, 20 bar H2). This work expands the covalent organic frameworks for the material family and its support catalyst, opening up new catalytic applications in the economical, practical, and effective synthesis of secondary amines. Catalysis ; Reductive amination ; Amination ; Chemistry ; Environmentally friendly ; Covalent bond ; Organic chemistry ; Transition metal ; Covalent organic framework ; Combinatorial chemistry Covalent Organic Framework Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Asymmetric Hydrogenation and Catalysis
Authors: Shengquan Hu | Jing Liu | Sikang Chen | Jian Gao | Yubo Zhou | Tao Liu | Xiaowu Dong
Source: Biological and Pharmaceutical Bulletin (article, 2021-11-30)
Field: Chemistry — Organic Chemistry

Discover Novel Covalent Inhibitors Targeting FLT3 through Hybrid Virtual Screening Strategy FMS-like tyrosine kinase 3 (FLT3) plays a very important role in regulating the proliferation, differentiation and survival of normal hematopoietic stem cells. Internal tandem duplications of the FLT3 gene (FLT3-ITD) mutations are present in 25% of all acute myeloid leukemia (AML) patients and are frequently associated with adverse clinical outcomes. Therefore, FLT3-ITD is a promising target for the treatment of AML. The use of covalent virtual screenings has shown that efficient rational approaches for the rapid discovery of new drugs scaffold. Herein, we report a hybrid virtual screening strategy that led to the discovery of FLT3 inhibitors. Using the combination of non-covalent docking and covalent docking, 8 compounds were found to inhibit FLT3, and G856-8335, S346-0154 are also effective against mutant FLT3. These two compounds also show selectivity to receptor tyrosine kinase (C-KIT), which has the potential for optimization. And this work can be extended to the screening of other covalent inhibitors. Virtual screening ; Myeloid leukemia ; Docking (animal) ; Covalent bond ; Haematopoiesis ; Tyrosine kinase ; Fms-Like Tyrosine Kinase 3 ; Receptor tyrosine kinase ; Chemistry ; Drug discovery ; Pharmacology ; Kinase ; Cancer research ; Stem cell ; Biochemistry ; Receptor ; Gene ; Biology ; Medicine ; Cell biology ; Mutation Click Chemistry and Applications ; Advanced biosensing and bioanalysis techniques ; Protein Degradation and Inhibitors
Authors: Nazariy T. Pokhodylo | Yurii Slyvka | Volodymyr Pavlyuk
Source: Acta Crystallographica Section E Crystallographic Communications (article, 2021-09-28)
Field: Chemistry — Organic Chemistry

Synthesis, crystal structure and Hirshfeld surface analysis of 5-cyclopropyl-<i>N</i>-(2-hydroxyethyl)-1-(4-methylphenyl)-1<i>H</i>-1,2,3-triazole-4-carboxamide The title compound, C 15 H 18 N 4 O 2 , was obtained via a two-step synthesis (Dimroth reaction and amidation) for anticancer activity screening and was selected from a 1 H -1,2,3-triazole-4-carboxamide library. The cyclopropyl ring is oriented almost perpendicular to the benzene ring [dihedral angle = 87.9 (1)°], while the dihedral angle between the mean plane of the cyclopropyl ring and that of the triazole ring is 55.6 (1)°. In the crystal, the molecules are linked by O—H...O and C—H...N interactions into infinite ribbons propagating in the [001] direction, which are interconnected by weak C—H...O interactions into layers. The intermolecular interactions were characterized via Hirshfeld surface analysis, which indicated that the largest fingerprint contact percentages are H...H (55.5%), N...H/H...N (15.4%), C...H/H...C (13.2%) and O...H/H...O (12.9%). Chemistry ; Carboxamide ; Crystal structure ; Crystallography ; 1,2,4-Triazole ; Stereochemistry ; Medicinal chemistry Synthesis and Biological Evaluation ; Chemical Synthesis and Analysis ; Synthesis of heterocyclic compounds
Authors: Jorge Juan Vicedo | Emilio Laguna Lumbreras | Segundo Ríos | José Luis Casas
Source: Nereis Interdisciplinary Ibero-American Journal of Methods Modelling and Simulation (article, 2021-11-15)
Field: Chemistry — Organic Chemistry

Ornamental potential of the coastal plant Lapiedra martinezii Lag. (Amaryllidaceae): the role of its revalorization in xero-gardening and ex-situ conservation Lapiedra martinezii Lag. (Amaryllidaceae) is an autumn-flowering geophyte that grows in coastal and sublittoral environments. The interests on this species has come out during the last decades due to its content in bioactive alkaloids and its conservational status. The aim of this work was to review the available information on L. martinezii and to assess whether it could be introduced as ornamental plant in xero-gardening. Therefore, the aesthetic traits were analyzed and compared to other cultivated and wild plants. Also, information on its ecological and propagation requirements were checked to discern whether it could be adapted under different production systems and culture conditions. In addition, other aspects were also analyzed to identify strengths and limitations of this species for its further revalorization as ornamental plant. The results obtained suggest that L. martinezii could be a good choice as foliage plant to grow it on gardens as an alpine bulb or pot plant. Moreover, it might be quite well adapted under different production and culture conditions in dry and semi-arid regions. The horticultural traits related to its germination and in vitro multiplication are interesting strengths to bear in mind for its industrial propagation and early domestication. Finally considered, the introduction in xero-gardening could also help in its ex-situ conservation. However, a more-in-depth research would be needed to finally introduce it in the ornamental plants’ market. Ornamental plant ; Biology ; Amaryllidaceae ; Domestication ; Arid ; Germination ; Ecology ; Botany Chemical synthesis and alkaloids ; Mycorrhizal Fungi and Plant Interactions ; Botanical Research and Applications