jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ülküye Dudu Gül | Zeynep Mine Şenol | Burcu Ertit Taştan
Source: Water Science & Technology (article, 2021-12-09)
Field: Chemistry — Analytical Chemistry

Treatment of the Allura Red food colorant contaminated water by a novel cyanobacterium <i>Desertifilum tharense</i> Abstract The biosorption properties of a newly isolated and identified cyanobacterium called Desertifilum tharense were investigated in the current study. Following morphological and molecular identification (16S rRNA sequencing analysis), the food colorant removal potential of this new isolate was determined. Moreover, the isotherm, kinetic, and thermodynamic studies were performed, and also the biosorbent characterization was studied after and before colorant biosorption with Fourier transform infrared and scanning electron microscopy analysis. Additionally, the changes in chlorophyll content of the biosorbent were examined after and before colorant treatment. The newly isolated cyanobacterial biosorbent removed 97% of Allura Red food colorant/dye at 1,500 mg L−1 initial dye concentration successfully at optimal conditions. Langmuir isotherm and pseudo-second-order kinetic models were fitted with the biosorption of the dye. The D-R model showed that the biosorption process occurred physically. The chlorophyll-a content of the biosorbent was negatively affected by the biosorption. The newly isolated and identified cyanobacterium seems to be a successful candidate for use to treat highly dye concentrated wastewaters. Biosorption ; Chemistry ; Langmuir adsorption model ; Nuclear chemistry ; Fourier transform infrared spectroscopy ; Chlorophyll a ; Adsorption ; Chromatography ; Environmental chemistry ; Environmental engineering ; Chemical engineering ; Organic chemistry ; Biochemistry ; Environmental science Dye analysis and toxicity ; Enzyme-mediated dye degradation ; Adsorption and biosorption for pollutant removal
Authors: Qin Yu | P. Alex Greaney | T. Matthew Evans | Jamie J. Kruzic
Source: International Journal of Plasticity (article, 2021-07-14)
Field: Materials Science — Materials Chemistry

A critical dislocation velocity for serration mechanism transition in a nickel-chromium solid solution alloy Serration ; Materials science ; Strain rate ; Dislocation ; Dynamic strain aging ; Plasticity ; Portevin–Le Chatelier effect ; Strain (injury) ; Crystallography ; Deformation (meteorology) ; Alloy ; Composite material ; Metallurgy ; Chemistry Microstructure and mechanical properties ; High Temperature Alloys and Creep ; Advanced materials and composites
Authors: Dina Farinha | Michael T. Migawa | Ana Bela Sarmento‐Ribeiro | Henrique Faneca
Source: International Journal of Nanomedicine (article, 2021-05-01)
Field: Materials Science — Biomaterials

A Combined Antitumor Strategy Mediated by a New Targeted Nanosystem to Hepatocellular Carcinoma The developed formulation resulted in a high and synergistic antitumor effect, revealing a translational potential to improve therapeutic approaches against HCC. Flow cytometry ; Cancer research ; Programmed cell death ; Cancer cell ; Nanocarriers ; Apoptosis ; Viability assay ; Context (archaeology) ; Drug delivery ; Materials science ; Chemistry ; Biophysics ; Cancer ; Biology ; Molecular biology ; Nanotechnology ; Biochemistry Nanoparticle-Based Drug Delivery ; Computational Drug Discovery Methods ; Nanoplatforms for cancer theranostics
Authors: Irene Rodrı́guez | Ester Saavedra | Henoc del Rosario | Juan Perdomo | José Quintana | Filippo Prencipe | Paola Oliva | Romeo Romagnoli | Francisco Estévez
Source: International Journal of Molecular Sciences (article, 2021-12-15)
Field: Chemistry — Organic Chemistry

Apoptosis Pathways Triggered by a Potent Antiproliferative Hybrid Chalcone on Human Melanoma Cells The World Health Organization reported that approximately 324,000 new cases of melanoma skin cancer were diagnosed worldwide in 2020. The incidence of melanoma has been increasing over the past decades. Targeting apoptotic pathways is a potential therapeutic strategy in the transition to preclinical models and clinical trials. Some naturally occurring products and synthetic derivatives are apoptosis inducers and may represent a realistic option in the fight against the disease. Thus, chalcones have received considerable attention due to their potential cytotoxicity against cancer cells. We have previously reported a chalcone containing an indole and a pyridine heterocyclic rings and an α-bromoacryloylamido radical which displays potent antiproliferative activity against several tumor cell lines. In this study, we report that this chalcone is a potent apoptotic inducer for human melanoma cell lines SK-MEL-1 and MEL-HO. Cell death was associated with mitochondrial cytochrome <i>c</i> release and poly(ADP-ribose) polymerase cleavage and was prevented by a non-specific caspase inhibitor. Using SK-MEL-1 as a model, we found that the mechanism of cell death involves (i) the generation of reactive oxygen species, (ii) activation of the extrinsic and intrinsic apoptotic and mitogen-activated protein kinase pathways, (iii) upregulation of TRAIL, DR4 and DR5, (iv) downregulation of p21<sup>Cip1/WAF1</sup> and, inhibition of the NF-κB pathway. Chalcone ; Apoptosis ; Programmed cell death ; Melanoma ; Downregulation and upregulation ; Cancer research ; Cytochrome c ; Chemistry ; Cancer cell ; Poly ADP ribose polymerase ; Cell growth ; Cell cycle ; Biology ; Cancer ; Biochemistry ; Stereochemistry ; Polymerase Synthesis and biological activity ; Genomics, phytochemicals, and oxidative stress ; Redox biology and oxidative stress
Authors: Olga Cruz‐López | Matilde Ner | Francho Nerín-Fonz | Yaiza Jiménez-Martínez | David Alencar Araripe | Juan Antonio Marchal | Houría Boulaiz | Hugo Gutiérrez‐de‐Terán | Joaquín M. Campos Rosa | Ana Conejo‐García
Source: Journal of Enzyme Inhibition and Medicinal Chemistry (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

Design, synthesis, HER2 inhibition and anticancer evaluation of new substituted 1,5-dihydro-4,1-benzoxazepines A series of 11 new substituted 1,5-dihydro-4,1-benzoxazepine derivatives was synthesised to study the influence of the methyl group in the 1-(benzenesulphonyl) moiety, the replacement of the purine by the benzotriazole bioisosteric analogue, and the introduction of a bulky substituent at position 6 of the purine, on the biological effects. Their inhibition against isolated HER2 was studied and the structure-activity relationships have been confirmed by molecular modelling studies. The most potent compound against isolated HER2 is <b>9a</b> with an IC<sub>50</sub> of 7.31 µM. We have investigated the effects of the target compounds on cell proliferation. The most active compound (<b>7c</b>) against all the tumour cell lines studied (IC<sub>50</sub> 0.42-0.86 µM) does not produce any modification in the expression of pro-caspase 3, but increases the caspase 1 expression, and promotes pyroptosis. Chemistry ; Stereochemistry ; Pharmacology ; Medicine Synthesis and biological activity ; Cancer therapeutics and mechanisms ; Synthesis and Biological Evaluation
Authors: Tânia M. F. Alves | Guilherme A. M. Jardim | Marco A. B. Ferreira
Source: RSC Advances (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

A green metal-free “one-pot” microwave assisted synthesis of 1,4-dihydrochromene triazoles The synthesis of several 4-aryl-1,4-dihydrochromene-triazoles was achieved <i>via</i> a metal-free "one-pot" procedure using PEG400 as the sole solvent in an eco-friendly process. Using microwave irradiation, the triazole derivatives were obtained in good yields and short reaction times starting from readily accessible building blocks. Environmentally friendly ; Microwave irradiation ; Microwave ; Aryl ; Metal ; Solvent ; Combinatorial chemistry ; Green chemistry ; Chemistry ; Organic chemistry ; Materials science ; Computer science ; Reaction mechanism ; Catalysis Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Synthesis and Biological Evaluation
Authors: Illia Lenko | Alexander Mamontov | C. Alayrac | Rémi Legay | B. Witulski
Source: Angewandte Chemie International Edition (article, 2021-08-19)
Field: Chemistry — Organic Chemistry

Media‐Driven Pd‐Catalyzed Reaction Cascades with 1,3‐Diynamides Leading Selectively to Either Indoles or Quinolines Divergent Pd-catalyzed reaction cascades with various 1,3-diynamides yielding either 2-amino-3-alkynylindoles or 2-amino-4-alkenylquinolines were established. Omitting or adding TBAF (tetrabutylammonium fluoride) to the reaction of N,N-(2-iodophenyl)(4-toluenesulfonyl)-1,3-diynamides with secondary or primary amines in the presence of KOH in THF and catalytic amounts of Pd(PPh<sub>3</sub> )<sub>4</sub> completely changed the outcome of the reaction. In the absence of TBAF, 2-amino-3-alkynylindoles were the sole products, while the presence of TBAF switched the product formation to 2-amino-4-alkenylquinolines. Deuterium labeling proceeded selectively at the C3 and C11 positions of the 2-amino-4-alkenylquinoline products and this suggests the unprecedented formation of [4]cumulenimines from 1,3-diynamides as reactive key intermediates. Chemistry ; Catalysis ; Tetrabutylammonium fluoride ; Medicinal chemistry ; Deuterium ; Combinatorial chemistry ; Organic chemistry Catalytic Alkyne Reactions ; Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions
Authors: Hany S. Mansour | Hend A. A. Abd El-wahab | Ahmed M. Ali | Tarek Aboul‐Fadl
Source: RSC Advances (article, 2021-01-01)
Field: Chemistry — Organic Chemistry

Inversion kinetics of some <i>E</i>/<i>Z</i> 3-(benzylidene)-2-oxo-indoline derivatives and their <i>in silico</i> CDK2 docking studies The structure-based design of some CDK2 inhibitors with a 3-(benzylidene)indolin-2-one scaffold as potential anticancer agents was realized. Target compounds were obtained as <i>E</i>/<i>Z</i> mixtures and were resolved to corresponding <i>E</i>- and <i>Z</i>-diastereomers. <i>In silico</i> studies using MOE 2019.01 software revealed better docking on the targeted enzyme for the <i>Z</i>-diastereomer compared to the <i>E</i>-one. A time-dependent kinetic isomerization study was carried out for the inversion of <i>E</i>/<i>Z</i> diastereomers in DMSO-d<sub>6</sub> at room temperature, and were found to obey the first order kinetic reactions. Furthermore, a determination of the kinetic inter-conversion rate order by graphical analysis method and calculation of the rate constant and half-life of this kinetic process were carried out. For the prediction of the stability of the diastereomer(s), a good multiple regression equation was generated between the reaction rates of isomerization and some QM parameters with significant <i>p</i> value. Kinetics ; Indoline ; Isomerization ; Chemistry ; Stereochemistry ; Organic chemistry ; Physics ; Catalysis Synthesis of Indole Derivatives ; Catalytic Cross-Coupling Reactions ; Synthesis of Organic Compounds
Authors: Jiaqi Zu | Zhengjun Yao | Ruiyang Tan | Liqiang Jin | Li Wan | Jinsen Hou | Pïng Chen | Jintang Zhou
Source: Journal of Magnetism and Magnetic Materials (article, 2021-09-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Optimizing the electromagnetic parameters and microwave absorption of corrosion-resistant FCIP@EP by data-driven discovery Materials science ; Microwave ; Corrosion ; Epoxy ; Composite number ; Composite material ; Percolation threshold ; Absorption (acoustics) ; Computer science ; Telecommunications ; Electrical resistivity and conductivity Electromagnetic wave absorption materials ; Natural Fiber Reinforced Composites ; Fiber-reinforced polymer composites
Authors: Bao Meng | Y.Z. Liu | Min Wan | M.W. Fu
Source: International Journal of Mechanical Sciences (article, 2021-05-11)
Field: Materials Science — Materials Chemistry

A multiscale constitutive model coupled with martensitic transformation kinetics for micro-scaled plastic deformation of metastable metal foils Materials science ; Diffusionless transformation ; Metastability ; Hardening (computing) ; Martensite ; Austenite ; Work hardening ; Composite material ; FOIL method ; Grain size ; Constitutive equation ; Strain hardening exponent ; Austenitic stainless steel ; Deformation (meteorology) ; Metallurgy ; Thermodynamics ; Finite element method ; Microstructure ; Layer (electronics) ; Physics Microstructure and mechanical properties ; Microstructure and Mechanical Properties of Steels ; Metallurgy and Material Forming
Authors: Abotaleb Abdelazim | Mahmoud Abu El Ela | Ahmed H. El-Banbi | Helmy Sayyouh
Source: Journal of Petroleum Exploration and Production Technology (article, 2021-10-23)
Field: Chemistry — Analytical Chemistry

Successful approach to mitigate the asphaltenes precipitation problems in ESP oil wells Abstract This study introduces a comprehensive and cost-effective approach to diagnose and treat the asphaltenes precipitation problems in different downhole conditions. The proposed approach has been successfully applied in two oil wells (Well-I, and Well-II) located in the Western Desert of Egypt. The two wells produce oil of moderate to high oil gravity with low asphaltenes content using Electrical Submersible Pumps (ESP). In such operating conditions, solid deposits caused blockage at the pump intake and within the pumping stages in the two wells. This blockage led to a sharp decrease in oil production rate and a significant increase in the operating cost. The existing failure analysis procedure was not able to accurately identify the reasons for the blockage; accordingly, the treatment operations were unsuccessful. On the contrary, applying the proposed approach accurately (1) identified the type of the solid deposits, (2) solved the problem using proper treatment option with minimum cost, and (3) improved the oil production rate. The laboratory tests of the fluid and solid deposits showed that (1) the asphaltenes were unstable in the crude oil and acted as a glue for other minerals, and (2) the blockage was successfully diagnosed to confirm that the two wells had asphaltenes precipitation problem. The laboratory tests were extended to select optimum asphaltene dispersant for wells treatments. The field application results showed a significant increase in the oil production rate from 700 to 1600 STB/D in Well-I and from 470 to 1500 STB/D in Well-II. Moreover, the operating cost decreased considerably from 2.01 to 0.43 $/STB in Well-I, and from 4.37 to 0.52 $/STB in Well-II after applying the proposed approach. Asphaltene ; Petroleum engineering ; Precipitation ; Dispersant ; Oil well ; Crude oil ; Offshore geotechnical engineering ; Environmental science ; Oil field ; API gravity ; Petroleum ; Geology ; Oil production ; Geotechnical engineering ; Meteorology ; Dispersion (optics) Petroleum Processing and Analysis ; Oil and Gas Production Techniques ; Enhanced Oil Recovery Techniques
Authors: Filip Vuković | Tiffany R. Walsh
Source: Composites Science and Technology (article, 2021-09-23)
Field: Materials Science — Materials Chemistry

Practical atomistic models of carbon fiber surfaces with tuneable topology and topography Materials science ; Molecular dynamics ; Fiber ; Topology (electrical circuits) ; Surface (topology) ; Nanotechnology ; Composite material ; Geometry ; Computational chemistry ; Mathematics ; Chemistry Graphene research and applications ; Fiber-reinforced polymer composites ; Carbon Nanotubes in Composites
Authors: Scott K. Bur | William C. K. Pomerantz | Morgan L. Bade | Clifford T. Gee
Source: Journal of Chemical Education (article, 2021-05-11)
Field: Chemistry — Physical and Theoretical Chemistry

Fragment-Based Ligand Discovery Using Protein-Observed <sup>19</sup>F NMR: A Second Semester Organic Chemistry CURE Project Curriculum-based undergraduate research experiences (CUREs) have been shown to increase student retention in STEM fields and are starting to become more widely adopted in chemistry curricula. Here we describe a 10-week CURE that is suitable for a second-semester organic chemistry laboratory course. Students synthesize small molecules and use protein-observed <sup>19</sup>F (PrOF) NMR to assess the small molecule's binding affinity to a target protein. The research project introduced students to multistep organic synthesis, structure-activity relationship studies, quantitative biophysical measurements (measuring <i>K</i><sub>d</sub> from PrOF NMR experiments), and scientific literacy. Docking experiments could be added to help students understand how changes in a ligand structure may affect binding to a protein. Assessment using the CURE survey indicates self-perceived skill gains from the course that exceed gains measured in a traditional and an inquiry-based laboratory experience. Given the speed of the binding experiment and the alignment of the synthetic methods with a second-semester organic chemistry laboratory course, a PrOF NMR fragment-based ligand discovery lab can be readily implemented in the undergraduate chemistry curriculum. Chemistry ; Curriculum ; Ligand (biochemistry) ; Molecule ; Organic molecules ; Mathematics education ; Organic chemistry ; Psychology ; Biochemistry ; Pedagogy Various Chemistry Research Topics ; Chemical Safety and Risk Management ; Innovative Teaching Methods
Authors: Amartya Bhattacharjee | Anindya Bhaduri | Ryan Hurley | Lori Graham‐Brady
Source: Journal of Applied Mechanics (article, 2021-01-19)
Field: Materials Science — Materials Chemistry

Failure Modeling and Sensitivity Analysis of Ceramics Under Impact Abstract A micromechanical multi-physics model for ceramics has been recalibrated and used to simulate impact experiments with boron carbide in abaqus. The dominant physical mechanisms in boron carbide have been identified and simulated in the framework of an integrated constitutive model that combines crack growth, amorphization, and granular flow. The integrative model is able to accurately reproduce some of the key cracking patterns of Sphere Indentation experiments and Edge On Impact experiments. Based on this integrative model, linear regression has been used to study the sensitivity of sphere indentation model predictions to the input parameters. The sensitivities are connected to physical mechanisms, and trends in model outputs have been intuitively explored. These results help suggest material modifications that might improve material performance, prioritize calibration experiments for materials-by-design iterations, and identify model parameters that require more in-depth understanding. Boron carbide ; Sensitivity (control systems) ; Indentation ; Ceramic ; Materials science ; Constitutive equation ; Calibration ; Silicon carbide ; Cracking ; Mechanics ; Computer science ; Structural engineering ; Composite material ; Finite element method ; Physics ; Engineering High-Velocity Impact and Material Behavior ; Advanced ceramic materials synthesis ; Advanced Surface Polishing Techniques
Authors: Nico Symma | Marek Bütergerds | Jandirk Sendker | Frank Petereit | Alexander Hake | Martina Düfer | Andreas Hensel
Source: Planta Medica (article, 2021-01-12)
Field: Chemistry — Organic Chemistry

Novel Piperidine and 3,4-dihydro-2H-pyrrole Alkaloids from Tilia platyphyllos and Tilia cordata Flowers Lime flowers, traditionally used for medical purposes for the treatment of symptoms of the common cold and mental stress, consist of the dried inflorescences including the floral bracts of <i>Tilia cordata, Tilia platyphyllos, Tilia × vulgaris</i>, or mixtures thereof. During phytochemical investigations, 6 different alkaloids - not described until now - were detected in <i>T. cordata</i> and <i>T. platyphyllos</i> flowers. They have been isolated and characterized as alkaloids with a dihydro-pyrrole and a piperidine substructure, respectively. Compounds 1A: and 1B: (tiliines A and B) are characterized as 2 diastereomers containing a 2-methyl-3,4-dihydro-2<i>H</i>-pyrrol-3-ol, connected via a C-10 alkyl chain to a <i>O</i>-glucosylated hydroquinone moiety. Compounds 2A: and 2B: (tiliamines A and B) are diastereomers of a 2-methyl-substituted piperidin-3-ol, coupled via a C-9 alkyl chain again to an <i>O</i>-glucosylated hydroquinone moiety. Compounds 3A: and 3B: (tilacetines A and B) are 3-<i>O</i>-acetylated derivatives of tiliamines. Quantification of the 6 alkaloids by HPLC-ESI-qTOF analysis indicated the presence of all alkaloids in <i>T. cordata</i> flowers and <i>T. platyphyllos</i> flowers, bracts, and leaves, with tiliines A and B and tilacetines A and B being the major compounds. Acetone/water turned out be the best extraction solvent for the alkaloids, but ethanol and ethanol/water mixtures also can be used for effective extraction. Furthermore, the alkaloids are found in hot water extracts, which are typically used in the traditional medicine. Bract ; Tilia ; Piperidine ; Botany ; Chemistry ; Phytochemical ; Organic chemistry ; Traditional medicine ; Inflorescence ; Biology Chemical synthesis and alkaloids ; Plant chemical constituents analysis ; Biochemical Analysis and Sensing Techniques
Authors: Yi Qian | Jinying Zheng | Long Li | Peng Qiao | Ying Li | Yinghui Duan | Guozhang Chang
Source: RSC Advances (article, 2021-01-01)
Field: Materials Science — Polymers and Plastics

Application of the synergistic flame retardant europium hydrotalcite/graphene oxide hybrid material and zinc borate to thermoplastic polyurethane In this paper, a certain amount of rare earth (europium) was doped into magnesium aluminum salt solution and assembled with graphene oxide (GO) by electrostatic interaction under alkaline conditions. Then, the EuMgAl-LDH/GO hybrid material was synthesized by a hydrothermal method. Its microstructure was analyzed and tested by X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR), the results indicated that the EuMgAl-LDH/GO hybrid material had been successfully prepared. Next, it was mixed with zinc borate and added to a thermoplastic polyurethane (TPU) (thermoplastic polyurethane) matrix by melting blending. The flame retardant and smoke suppression effect of the composite was tested by conical calorimetry. The results showed that, compared with simple TPU, the PHRR (peak heat release rate), THR (total heat release), PSPR (peak smoke production rate) and TSP (total smoke production) value of the composite material decreased by 65.6%, 16.2%, 61% and 37.1%, respectively. Finally, through analysis of the carbon residue after combustion of the TPU composite material, we found that the formed carbon layer is denser and the char yield is greatly improved. Materials science ; Thermoplastic polyurethane ; Zinc borate ; Fire retardant ; Fourier transform infrared spectroscopy ; Graphene ; Zinc ; Hydrotalcite ; Composite material ; Chemical engineering ; Polyurethane ; Char ; Composite number ; Combustion ; Chemistry ; Metallurgy ; Organic chemistry ; Elastomer Flame retardant materials and properties ; Layered Double Hydroxides Synthesis and Applications ; Magnesium Oxide Properties and Applications