jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Weian Yan | Hassen Riahi | Karim Benzarti | Robert Chlela | Laurence Curtil | David Bigaud
Source: Mathematical Problems in Engineering (article, 2021-02-09)
Field: Materials Science — Polymers and Plastics

Durability and Reliability Estimation of Flax Fiber Reinforced Composites Using Tweedie Exponential Dispersion Degradation Process Flax fiber reinforced composites are demonstrating promising outcomes which make them potential candidates to replace synthetic composites in various industrial applications. However, there is limited information regarding their long-term performance, and it is usually acknowledged that natural fibers are less resistant than their synthetic counterparts. In this context, it is crucial to study their durability before considering their use for structural rehabilitation and strengthening in construction. This research aims to study and predict the performance of flax fiber reinforced polymer (FFRP) composites with a biobased epoxy matrix. The test program consists in exposing FFRP laminates and FFRP strengthened concrete slabs to different accelerated ageing conditions over a total period of two years. In the present study, not a single stress variable but various combinations and coupling of two environmental stress variables, temperature (T) and relative humidity (RH), are considered, thereby distinguishing this study from most of the works reported in the literature. Then, a series of mechanical destructive tests are performed periodically on aged samples to evaluate property evolutions over ageing time. The collected experimental data are analyzed to develop a performance evolution model and to evaluate the service lifetime performance of this new biobased FFRP composite. For that, the potential of the Tweedie exponential dispersion (TED) process model, which takes some famous stochastic processes (Wiener process, Gamma process, and inverse Gaussian process) as special cases, is investigated. The TED process modeling, particularly interesting in the cases of complicated degradation mechanisms, is written here for destructive tests and, finally, a reliability analysis based on the TED process model determined is carried out in order to update the FRP design equations provided by international codes in the specific case of FFRP. Durability ; Materials science ; Composite material ; Reliability (semiconductor) ; Context (archaeology) ; Thermosetting polymer Natural Fiber Reinforced Composites ; Structural Behavior of Reinforced Concrete ; Mechanical Behavior of Composites
Authors: Sheau‐Fung Thai | Carlton P. Jones | Brian L. Robinette | Hongzu Ren | Beena Vallanat | Anna Fisher | Kirk T. Kitchin
Source: Journal of Nanoscience and Nanotechnology (article, 2021-05-13)
Field: Materials Science — Materials Chemistry

Effects of Silver Nanoparticles and Silver Nitrate on mRNA and microRNA Expression in Human Hepatocellular Carcinoma Cells (HepG2) In order to understand toxicity of nano silver, human hepatocellular carcinoma (HepG2) cells were treated either with silver nitrate (AgNO₃) or with nano silver capped with glutathione (Ag-S) at various concentration. Differentially expressed genelists for mRNA and microRNA were obtained through Illumina RNA sequencing and DEseq data analyses. Both treatments showed non-linear dose response relationships for mRNA and microRNA. Gene expression analysis showed signaling pathways common to both nano Ag-S and AgNO₃, such as cell cycle regulation, DNA damage response and cancer related pathways. But, nano Ag-S caused signaling pathway changes that were not altered by AgNO₃ such as NRF2-mediated oxidative stress response inflammation, cell membrane signaling, and cell proliferation. Nano Ag-S also affected p53 signaling, survival, apoptosis, tissue repair, lipid synthesis, angiogenesis, liver fibrosis and tumor development. Several of the pathways affected by nano Ag-S are hypothesized as major contributors to nanotoxicity. MicroRNA target filter analysis revealed additional affected pathways that were not reflected in the mRNA expression response alone, including DNA damage signaling, genomic stability, ROS, cell cycle, ubiquitination, DNA methylation, cell proliferation and fibrosis for AgNO₃; and cell cycle regulation, P53 signaling, cell proliferation, survival, apoptosis, tissue repair and so on for nano Ag-S. These pathways may be mediated by microRNA repression of protein translation.Our study clearly showed that the addition of microRNA profiling increased the numbers of signaling pathways discovered that affected by the treatments on HepG2 cells and gave US a better picture of the effects of these reagents in the cells. Biology ; Cell cycle ; microRNA ; Signal transduction ; Cell growth ; Cell biology ; Biological pathway ; Angiogenesis ; Apoptosis ; Molecular biology ; Gene expression ; Cancer research ; Biochemistry ; Gene Nanoparticles: synthesis and applications ; MicroRNA in disease regulation ; Advanced Nanomaterials in Catalysis
Authors: Ge Meng | Yanzhi Wang | Francesco Carraro | Weibin Liang | Morteza Roostaeinia | Samira Siahrostami | Davide Μ. Proserpio | Christian J. Doonan | Paolo Falcaro | Haoquan Zheng | Xiaodong Zou | Zhehao Huang
Source: Angewandte Chemie (article, 2021-03-08)
Field: Chemistry — Inorganic Chemistry

High‐Throughput Electron Diffraction Reveals a Hidden Novel Metal–Organic Framework for Electrocatalysis Abstract Metal‐organic frameworks (MOFs) are known for their versatile combination of inorganic building units and organic linkers, which offers immense opportunities in a wide range of applications. However, many MOFs are typically synthesized as multiphasic polycrystalline powders, which are challenging for studies by X‐ray diffraction. Therefore, developing new structural characterization techniques is highly desired in order to accelerate discoveries of new materials. Here, we report a high‐throughput approach for structural analysis of MOF nano‐ and sub‐microcrystals by three‐dimensional electron diffraction (3DED). A new zeolitic‐imidazolate framework (ZIF), denoted ZIF‐EC1, was first discovered in a trace amount during the study of a known ZIF‐CO 3 ‐1 material by 3DED. The structures of both ZIFs were solved and refined using 3DED data. ZIF‐EC1 has a dense 3D framework structure, which is built by linking mono‐ and bi‐nuclear Zn clusters and 2‐methylimidazolates (mIm − ). With a composition of Zn 3 (mIm) 5 (OH), ZIF‐EC1 exhibits high N and Zn densities. We show that the N‐doped carbon material derived from ZIF‐EC1 is a promising electrocatalyst for oxygen reduction reaction (ORR). The discovery of this new MOF and its conversion to an efficient electrocatalyst highlights the power of 3DED in developing new materials and their applications. Electrocatalyst ; Zeolitic imidazolate framework ; Metal-organic framework ; Imidazolate ; Materials science ; Nanotechnology ; Chemical engineering ; Chemistry ; Inorganic chemistry ; Electrode ; Electrochemistry ; Physical chemistry ; Adsorption Metal-Organic Frameworks: Synthesis and Applications ; Machine Learning in Materials Science ; X-ray Diffraction in Crystallography
Authors: Marisol Ji | Andrea Jagodar | Eva Kovačević | Lazhar Benyahia | Fabienne Poncin‐Epaillard
Source: Materials Chemistry and Physics (article, 2021-04-21)
Field: Materials Science — Materials Chemistry

Characterization of functionalized coatings prepared from pulsed plasma polymerization Materials science ; Elastomer ; X-ray photoelectron spectroscopy ; Plasma polymerization ; Adhesive ; Polymer ; Plasma ; Chemical engineering ; Fourier transform infrared spectroscopy ; Polymerization ; Natural rubber ; Surface modification ; Polymer chemistry ; Composite material ; Layer (electronics) Diamond and Carbon-based Materials Research ; Metal and Thin Film Mechanics ; Surface Modification and Superhydrophobicity
Authors: Natalia I. Borzdun | Ruslan R. Ramazanov | Artyom D. Glova | Sergey V. Larin | Sergey V. Lyulin
Source: Energy & Fuels (article, 2021-04-12)
Field: Chemistry — Analytical Chemistry

Model Carboxyl-Containing Asphaltenes as Potential Acceptor Materials for Bulk Heterojunction Solar Cells We put forward chemically modified asphaltenes, polycyclic aromatic byproducts of deep oil refining, for use as novel low-cost acceptor materials for bulk heterojunction (BHJ) solar cells. The electronic properties of asphaltenes with varying chemical structures are studied by density functional theory (DFT), while the morphology of DFT-selected carboxyl-containing asphaltenes mixed with poly(3-hexylthiophene) (P3HT) as a model polymer-donor is investigated by means of all-atom molecular dynamics (MD) simulations. DFT calculations show that the chemical modification of asphaltenes with carboxyl groups enables their energy levels to be fine-tuned, thereby obtaining the desirable energy difference between the lowest unoccupied molecular orbitals of the acceptor and donor materials for efficient charge transfer. MD simulations reveal the heterophase morphology of the P3HT/asphaltene mixture, as well as the formation of extended stacks of asphaltenes via π–π stacking between their polyaromatic cores. Overall, from both the electronic and morphological standpoints, carboxyl-containing asphaltenes do indeed represent a potential low-cost acceptor for BHJ solar cells. Asphaltene ; Acceptor ; Polymer solar cell ; Density functional theory ; Stacking ; Organic solar cell ; Heterojunction ; Chemical physics ; Materials science ; Chemistry ; Chemical engineering ; Computational chemistry ; Polymer ; Organic chemistry ; Optoelectronics Petroleum Processing and Analysis ; Organic Electronics and Photovoltaics ; Photochemistry and Electron Transfer Studies
Authors: D. Sundhari | N. R. Dhineshbabu | S. Sutha | M.E. Raja Saravanan
Source: Materials Today Proceedings (article, 2021-01-01)
Field: Materials Science — Biomaterials

Encapsulation of bioactive agent (Curcumin, Moringa) in electrospun nanofibers – Some insights into recent research trends Electrospinning ; Nanofiber ; Materials science ; Nanotechnology ; Textile ; Curcumin ; Coronavirus disease 2019 (COVID-19) ; Composite material ; Polymer ; Chemistry ; Medicine ; Infectious disease (medical specialty) ; Disease Electrospun Nanofibers in Biomedical Applications ; Membrane Separation Technologies ; Polymer Nanocomposite Synthesis and Irradiation
Authors: Hung V. Nguyen | Alain Ibanez | Mathieu Salaün | Stéphanie Kodjikian | Philippe Trens | Xavier Cattoën
Source: Microporous and Mesoporous Materials (article, 2021-02-24)
Field: Materials Science — Materials Chemistry

Synthesis and properties of porous ester-silica nanoparticles Tetraethyl orthosilicate ; Zeta potential ; Hydrolysis ; Nanoparticle ; Chemical engineering ; Rhodamine B ; Porosity ; Chemistry ; Adsorption ; Hydrophobic silica ; Lipophilicity ; Mesoporous silica ; Organic chemistry ; Mesoporous material ; Catalysis Mesoporous Materials and Catalysis ; Analytical Chemistry and Chromatography ; Catalytic Processes in Materials Science
Authors: Dan Zhao | Lijun Song | Linxi Hou
Source: ACS Omega (article, 2021-09-20)
Field: Materials Science — Materials Chemistry

Efficient Persistent Luminescence Tuning Using a Cyclodextrin Inclusion Complex as Efficient Light Conversion Materials Developing an appropriate method to broaden the color of long persistent luminescence materials has important scientific significance and practical value but remains a great challenge. Herein, we have developed a unique strategy to fine-tune the persistent luminescence using the inclusion complex of rhodamine 6G with (2-hydroxypropyl)-β-cyclodextrin as efficient light conversion materials. The emitting color of the novel persistent luminescence material could be tuned from green to orange by changing the concentration of the light conversion agent. Furthermore, afterglow decay measurements showed that the initial afterglow brightness is 9.65 cd/m<sup>2</sup>, and the initial afterglow brightness gradually decreased as the cyclodextrin inclusion compound coating increased. This design concept introduces a new perspective for broadening the luminescence color of afterglow phosphors, which may open up new opportunities for persistent luminescence materials toward many emerging applications. Afterglow ; Luminescence ; Phosphor ; Brightness ; Persistent luminescence ; Materials science ; Cyclodextrin ; Optoelectronics ; Photochemistry ; Nanotechnology ; Optics ; Chemistry ; Physics ; Organic chemistry Luminescence and Fluorescent Materials ; Luminescence Properties of Advanced Materials ; Lanthanide and Transition Metal Complexes
Authors: Mayank Mayank | Jayant Sindhu | Ashutosh Singh | Namyashree Nayak | Neha Garg | Navneet Kaur | Narinder Singh
Source: ACS Applied Bio Materials (article, 2021-10-06)
Field: Chemistry — Spectroscopy

Excited-State Intramolecular Hydrogen-Bonding-Assisted Restricted Rotation: A Mechanism for Monitoring Intracellular Viscosity and Distinguishing Malignant, Differentiating, and Apoptotic Cancer Cells We have successfully developed a sensor (<b>IP1</b>) that utilizes a confocal-based live-cell imaging technique for distinguishing malignant, differentiating, and under-apoptosis cancer cells. The intracellular viscosity (IVis) is minimum in the cancer cell, intermediate in differentiating cells, and maximum in the apoptotic cells. Therefore, we have developed a molecular rotor (<b>IP1</b>) that can sense the changes in intracellular viscosity. <b>IP1</b> works on the viscosity-assisted restricted-rotation mechanism and is facilitated by the excited-state intramolecular hydrogen-bonding phenomenon (ESIHB). The use of ESIHB has fine-tuned the viscosity-sensing properties of <b>IP1</b>, which in turn has greatly helped in our quest of distinguishing the malignant, differentiating, and apoptotic cancer cells by the <b>IP1</b> probe. It was very effective in monitoring apoptosis by increased fluorescence intensity by the confocal live-cell imaging technique. The noncytotoxic behavior, even at 10 μg/mL concentration, is a charming feature of the developed probe. To the best of our knowledge, this is the first report for the ESIHB-based fluorescence probe that can distinguish malignant, differentiating, and apoptotic cancer cells by the use of live-cell imaging techniques. Intracellular ; Cancer cell ; Apoptosis ; Cell ; Biophysics ; Cancer ; Chemistry ; Materials science ; Biology ; Biochemistry ; Genetics Molecular Sensors and Ion Detection ; Metal complexes synthesis and properties ; Lanthanide and Transition Metal Complexes
Authors: S. Chahib | D. Fasquelle | G. Leroy
Source: Materials Science in Semiconductor Processing (article, 2021-09-27)
Field: Materials Science — Materials Chemistry

Density functional theory study of structural, electronic and optical properties of cobalt-doped BaSnO3 Density functional theory ; Materials science ; Band gap ; Dopant ; Doping ; Lattice constant ; Electronic band structure ; WIEN2k ; Direct and indirect band gaps ; Brillouin zone ; Condensed matter physics ; Optoelectronics ; Local-density approximation ; Computational chemistry ; Optics ; Diffraction ; Chemistry Electronic and Structural Properties of Oxides ; Ferroelectric and Negative Capacitance Devices ; Magnetic and transport properties of perovskites and related materials
Authors: Mara Klarner | Patricia Blach | Haiko Wittkämper | Niels de Jonge | Christian Papp | Rhett Kempe
Source: ChemCatChem (article, 2021-05-08)
Field: Chemistry — Inorganic Chemistry

Key Parameters for the Synthesis of Active and Selective Nanostructured 3d Metal Catalysts Starting from Coordination Compounds – Case Study: Nickel Mediated Reductive Amination Abstract The design of nanostructured catalysts based on earth‐abundant metals that mediate important reactions efficiently, selectively and with a broad scope is highly desirable. Unfortunately, the synthesis of such catalysts is poorly understood. We report here on highly active Ni catalysts for the reductive amination of ketones by ammonia employing hydrogen as a reducing agent. The key functions of the Ni‐salen precursor complex during catalyst synthesis have been identified: (1) Ni‐salen complexes sublime during catalyst synthesis, which allows molecular dispersion of the metal precursor on the support material. (2) The salen ligand forms a nitrogen‐doped carbon shell by decomposition, which embeds and stabilizes the Ni nanoparticles on the γ‐Al 2 O 3 support. (3) Parameters, such as flow rate of the pyrolysis gas, determine the carbon supply for the embedding process of Ni nanoparticles. Catalysis ; Reductive amination ; Nickel ; Metal salen complexes ; Nanoparticle ; Chemistry ; Ligand (biochemistry) ; Combinatorial chemistry ; Pyrolysis ; Amination ; Materials science ; Inorganic chemistry ; Organic chemistry ; Nanotechnology Asymmetric Hydrogenation and Catalysis ; Nanomaterials for catalytic reactions ; Ammonia Synthesis and Nitrogen Reduction
Authors: Ateeq Rahman | Viswanadha Srirama Rajasekhar Pullabhotla
Source: BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS (article, 2021-11-26)
Field: Materials Science — Materials Chemistry

Layered Double Hydroxide Catalysts Preparation, Characterization and Applications for Process Development: An Environmentally Green Approach The adage of new generation of fine chemicals process is the best process applied in the absence of conventional methods. However, many methods use different reaction parameters, such as basic and acidic catalysts, for example oxidation, reduction, bromination, water splitting, cyanohydrin, ethoxylation, syngas, aldol condensation, Michael addition, asymmetric ring opening of epoxides, epoxidation, Wittig and Heck reaction, asymmetric ester epoxidation of fatty acids, combustion of methane, NOx reduction, biodiesel synthesis, propylene oxide polymerization. Layered Double Hydroxides (LDHs) have received considerable attention due their potential applications in flame retardant and has excellent medicinal property for reducing acidity. These catalysts are characterized using analytical techniques, such as: X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), Raman spectroscopy, Thermogravimetric-Differential Thermal Analyzer (TG-DTA), Scanning electron microscope (SEM), Transmission electron microscopes (TEM), Brunauer-Emmett-Teller (BET) surface area, N2 Adsorption-desorption, Temperature programmed reduction (TPR), X-ray photoelectrons spectroscopy (XPS), which gives its overall picture of its structure, porosity, morphology, thermal stability, reusability, and activity of catalysts. LDHs catalysts have proven to be economic and environmentally friendly. The above discussed applications make these catalysts unique from Green Chemistry point of view since they are reusable, and eco-friendly catalysts. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). Catalysis ; Thermogravimetric analysis ; Layered double hydroxides ; Environmentally friendly ; Chemical engineering ; Chemistry ; Materials science ; Organic chemistry Layered Double Hydroxides Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Catalytic Processes in Materials Science
Authors: Małgorzata Czichy | Patryk Janasik | Paweł Wagner | David L. Officer | Mieczysław Łapkowski
Source: Materials (article, 2021-04-23)
Field: Materials Science — Polymers and Plastics

Electrochemical and Spectroelectrochemical Studies on the Reactivity of Perimidine–Carbazole–Thiophene Monomers towards the Formation of Multidimensional Macromolecules versus Stable π-Dimeric States During research on cross-linked conducting polymers, double-functionalized monomers were synthesized. Two subunits potentially able to undergo oxidative coupling were used-perimidine and, respectively, carbazole, 3,6-di(hexylthiophene)carbazole or 3,6-di(decyloxythiophene)carbazole; alkyl and alkoxy chains as groups supporting molecular ordering and 14<i>H</i>-benzo[4,5]isoquinone[2,1-a]perimidin-14-one segment promoting CH⋯O interactions and π-π stacking. Electrochemical, spectroelectrochemical, and density functional theory (DFT) studies have shown that potential-controlled oxidation enables polarization of a specific monomer subunit, thus allowing for simultaneous coupling via perimidine and/or carbazole, but mainly leading to dimer formation. The reason for this was the considerable stability of the dicationic and tetracationic π-dimers over covalent bonding. In the case of perimidine-3,6-di(hexylthiophene)carbazole, the polymer was not obtained due to the steric hindrance of the alkyl substituents preventing the coupling of the monomer radical cations. The only linear π-conjugated polymer was obtained through di(decyloxythiophene)carbazole segment from perimidine-di(decyloxythiophene)-carbazole precursor. Due to the significant difference in potentials between subsequent oxidation states of monomer, it was impossible to polarize the entire molecule, so that both directions of coupling could be equally favored. Subsequent oxidation of this polymer to polarize the side perimidine groups did not allow further crosslinking, because rather the π-π interactions between these perimidine segments dominate in the solid product. Carbazole ; Monomer ; Alkyl ; Polymerization ; Steric effects ; Thiophene ; Alkoxy group ; Dimer ; Polymer ; Polymer chemistry ; Chemistry ; Conjugated system ; Electrochemistry ; Materials science ; Photochemistry ; Organic chemistry ; Physical chemistry Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Synthesis and properties of polymers
Authors: Luca M. Cavinato | Giorgio Volpi | Elisa Fresta | Claudio Garino | Andréa Fin | Claudia Barolo
Source: Chemistry (article, 2021-07-06)
Field: Chemistry — Organic Chemistry

Microwave-Assisted Synthesis, Optical and Theoretical Characterization of Novel 2-(imidazo[1,5-a]pyridine-1-yl)pyridinium Salts In the last few years, imidazo[1,5-a]pyridine scaffolds and derivatives have attracted growing attention due to their unique chemical structure and optical behaviors. In this work, a series of pyridylimidazo[1,5-a]pyridine derivatives and their corresponding pyridinium salts were synthesized and their optical properties investigated to evaluate the effect of the quaternization on the optical features both in solution and polymeric matrix. A critical analysis based on the spectroscopic data, chemical structures along with density functional theory calculation is reported to address the best strategies to prevent aggregation and optimize the photophysical properties. The obtained results describe the relationship between chemical structure and optical behaviors, highlighting the role of pendant pyridine. Finally, the presence of a positive charge is fundamental to avoid any possible aggregation process in polymeric films. Pyridinium ; Pyridine ; Chemistry ; Density functional theory ; Characterization (materials science) ; Microwave ; Combinatorial chemistry ; Chemical structure ; Computational chemistry ; Organic chemistry ; Polymer chemistry ; Materials science ; Nanotechnology ; Computer science Synthesis and Reactivity of Heterocycles ; Synthesis and biological activity ; Multicomponent Synthesis of Heterocycles