jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Achraf El Kasmi | Muhammad Waqas | Zhen‐Yu Tian
Source: Applications in Energy and Combustion Science (article, 2020-11-03)
Field: Materials Science — Materials Chemistry

Insights into the role of surface functional species in Cu-Mn-O thin film catalysts for N2O decomposition Efficient N2O decomposition using catalytic materials has been gaining attention for long time. Catalytic materials based on noble metals have proved good feasibility; however, their applications are restricted because of the high cost and limited resources. Herein, low-cost catalysts based on copper manganese oxides were synthesized by chemical vapor deposition technique for N2O decomposition. The obtained catalysts were characterized to identify the structure, morphology, composition and arrangement of formed species. The results showed that the particles are getting agglomerated when increasing Mn content, which could be due to the difference in growth and crystallization rates of Cu and Mn. XPS analysis exhibited the existence of several active species such as, Cu and Mn cations, hydroxides and metal carbonates. The ratio of Cu/Mn in bulk is found to be in correlation with the catalytic activity. The catalytic tests of N2O decomposition revealed good activity of all catalysts, and the quality and quantity of the formed surface species have dramatic effect on the activity of the catalysts. When doping by Mn to promote the catalytic activity, formed Cu(OH)2 species at catalysts’ surface appeared to be good promoters in the studied reaction of N2O decomposition by C3H6. However, the existence of Cu metal, as more reduced Cu state, at the surface of catalysts is appeared to decrease the catalytic activity, which may play an inhibitor role in this studied reaction. In addition, Cu auger peak identification revealed the existence of Cu cations with varied oxidation states, leading to establish a correlated sequence of Cu1+>Cu2+>Cu0 with the catalytic activity. This approach of fine-tuning the surface formed species could lead to enhance the performance of other catalysts in different applications. Catalysis ; Decomposition ; X-ray photoelectron spectroscopy ; Copper ; Metal ; Inorganic chemistry ; Manganese ; Chemistry ; Oxidation state ; Materials science ; Chemical engineering ; Organic chemistry Catalytic Processes in Materials Science ; Copper-based nanomaterials and applications ; Nanomaterials for catalytic reactions
Authors: Marine Le Goas | Tom Roussel | Maria Kalbazova | David Carrière | Elodie Barruet | Valérie Geertsen | Giulia C. Fadda | Fabienne Testard | Géraldine Carrot | Jean‐Philippe Renault
Source: Journal of Materials Chemistry B (article, 2020-01-01)
Field: Materials Science — Biomaterials

Combining surface chemistry modification and <i>in situ</i> small-angle scattering characterization to understand and optimize the biological behavior of nanomedicines Nanomedicines are considered as promising therapeutics for cancer treatment. However, clinical translation is still scarce, partly because their biological behavior is not well understood. Extracting general guidelines from the great variety of nanoparticles and conditions studied is indeed difficult, and relevant techniques are lacking to obtain in situ information. Here, both issues are solved by combining versatile model nanoparticles with in situ tools based on small-angle scattering techniques (SAS). The strategy was to develop a library of nanoparticles and perform systematic study of their interactions with biological systems. Considering the promising properties of gold nanoparticles as cancer therapeutics, polymethacrylate-grafted gold nanoparticles were chosen as models. Modulation of polymer chemistry was shown to change the surface properties while keeping the same structure for all nanoparticles. This unity allowed reliable comparison to extract general principles, while the synthesis versatility enabled to fine-tune the nanoparticles surface properties, especially through copolymerization, and thus to optimize their biological behavior. Two specific aspects were particularly examined: colloidal stability and cell uptake. Positive charges and hydrophobicity were identified as key parameters influencing toxicity and internalization. In situ SAS gave valuable information about nanoparticles evolution in biologically relevant environments. Good colloidal stability was thereby shown in cell culture media, while intracellular transformation and quantity of nanoparticles were monitored, highlighting the potential of these techniques for nanomedicines studies. In situ ; Characterization (materials science) ; Surface modification ; Surface (topology) ; Nanotechnology ; Materials science ; Small-angle X-ray scattering ; Scattering ; Small-angle scattering ; Chemical engineering ; Chemistry ; Engineering ; Physics ; Organic chemistry ; Optics ; Geometry ; Mathematics Nanoparticle-Based Drug Delivery ; Graphene and Nanomaterials Applications ; RNA Interference and Gene Delivery
Authors: Satoki Kodani | Nobuyoshi Koga
Source: Journal of Chemical Education (article, 2020-12-22)
Field: Chemistry — Physical and Theoretical Chemistry

Discovering the Chemical Mechanism of Common Heating Agents: A Stepwise Inquiry with Student-Designed Experiments in a High School Laboratory Course A newly developed laboratory learning program for high school chemistry courses is discussed, in which students discover the chemical mechanism governing exothermic phenomena during the reaction between a heating agent, namely, calcium oxide (CaO)–aluminum (Al) mixture, and water. Based on prior knowledge of simple heating agents such as CaO, the students were able to accurately identify the component chemical reactions in the CaO–Al mixture and water system using three pairs of comparable thermometric measurements arranged in a stepwise manner. In each step, the students designed the comparative experiments for each student group through logical thinking and argumentation to obtain relevant and reliable results. Active interpretation of the results enabled each student to learn the chemical phenomena inherent in the observed reactions, and their understanding was deepened through evidence-based argumentation and debate. Finally, students in each group proposed an overall chemical mechanism governing the reaction between the CaO–Al mixture and water by consolidating the knowledge acquired during the previous inquiry steps. The proposed chemical mechanism was fine-tuned through group presentations, followed by question and answer sessions. The 6-h evidence-driven activity provided numerous opportunities for experiencing the multifaceted aspects of the scientific inquiry process. Argumentation theory ; Exothermic reaction ; Chemistry ; Mechanism (biology) ; Mathematics education ; Interpretation (philosophy) ; Concept learning ; Computer science ; Psychology ; Organic chemistry ; Epistemology Various Chemistry Research Topics ; Chemistry and Chemical Engineering ; Thermal and Kinetic Analysis
Authors: А. П. Шайкин | I. R. Galiev | V E Epishkin
Source: IOP Conference Series Materials Science and Engineering (article, 2020-01-01)
Field: Materials Science — General Materials Science

Influence flame speed and flame thickness on completeness of combustion hythane Abstract The article is dedicated to experimental and theoretical studies characteristics of flame propagation in combustion chamber of internal combustion engine with spark ignition and their influence on completeness combustion. It is theoretically and experimentally proved that relationship of flame propagation characteristics with completeness of combustion composite fuel is complex, non-linear, and depends on chemical composition combustible mixture and temperature in combustion chamber. It was revealed that an increase thickness near-wall unburned fuel layer, size of slots in combustion chamber and surface area of combustion chamber contribute to a reduction combustion efficiency of the fuel. It is shown that an increase rate flame propagation and a decrease thickness flame front leads to an increase completeness combustion fuel. It was revealed that proposed formula, using fundamental characteristics of flame propagation, allows calculating completeness combustion composite fuel. This indicates feasibility of using this formula at the design stage and fine-tuning low-emission and energy-efficient combustion chambers of engines and power plants. Combustion ; Ignition system ; Combustion chamber ; Materials science ; Mechanics ; Completeness (order theory) ; Flame speed ; Homogeneous charge compression ignition ; Internal combustion engine ; Premixed flame ; Nuclear engineering ; Automotive engineering ; Chemistry ; Thermodynamics ; Engineering ; Physics ; Mathematics ; Organic chemistry Material Properties and Applications ; Aerospace, Electronics, Mathematical Modeling ; Advanced Combustion Engine Technologies
Authors: Shuai Chen | Jeremy H. Yune | Zhiqian Zhang | Zhigang Liu | N. Sridhar | Linda Y. L. Wu | Shuyun Chng | Jun Liu
Source: The Journal of Physical Chemistry C (article, 2020-04-10)
Field: Materials Science — Surfaces, Coatings and Films

Multiscale Modeling to Predict the Hydrophobicity of an Experimentally Designed Coating Fine-tuning surface energies of coatings through experimental trial and error can be very tedious and time-consuming. The use of a reliable theoretical model can provide useful guidelines for experimental and formulation design for surface hydrophobicity. In this work, we perform multiscale modeling with molecular dynamics (MD) simulations, theoretical models, and computational fluid dynamics (CFD) simulations to investigate the wetting and sliding behavior of a water droplet on experimentally fabricated coatings. The wetting behavior of a water droplet on untreated polydimethylsiloxane (PDMS) surface and PDMS surface functionalized with hydroxyl and fluoride groups is studied by MD simulations. MD simulation results show that water contact angle (WCA) increases with increasing length of fluorocarbon chains, and this is in good agreement with experimental measurement of PDMS surface functionalized with C8F17. A theoretical model using the results from the MD simulation and inputs from experimental measurements of surface morphology is further proposed to predict the WCA of functionalized microstructured PDMS surface. The validated theoretical model shows that, though increasing the filler concentration aids in enhancing surface hydrophobicity, the separation distance between neighboring features decreases, weakening the hydrophobicity property and indicating there is an optimal filler concentration for the most hydrophobic surface. To perform multiscale modeling to predict the hydrophobicity of coating, the CFD model is constructed to predict droplet sliding and bouncing on an inclined surface in the macroscopic scale by using the WCA from MD simulations and theoretical model as input. The sliding and bouncing behaviors in CFD simulations are well-matched with the experimental observations on different hydrophobic surfaces. This multiscale model presented here is useful in the formulation design for controlled surface hydrophobicity of PDMS surfaces, and it facilitates the applications of PDMS in various aqueous systems. Polydimethylsiloxane ; Wetting ; Materials science ; Contact angle ; Molecular dynamics ; Computational fluid dynamics ; Coating ; Superhydrophobic coating ; Surface (topology) ; Composite material ; Nanotechnology ; Mechanics ; Chemistry ; Computational chemistry Surface Modification and Superhydrophobicity ; Fluid Dynamics and Heat Transfer ; Fluid Dynamics and Thin Films
Authors: Parshuram M. Pisal | Ajay S. Sawant | Vinod T. Kamble | Ravi Varala | Syed Farooq Adil | Mujeeb Khan | Mohammed Rafiq H. Siddiqui
Source: Organic Communications (article, 2020-03-28)
Field: Chemistry — Organic Chemistry

ZrCl4-catalyzed one-pot multi-component synthesis of hexahydropyrano pyrimidinone derivatives In this study, zirconium tetrachloride is used as a highly efficient catalyst for the one-pot three component reaction of 3,4-dihydro(2H)-pyran, urea and benzaldehyde in ethanol, producing corresponding hexahydropyrano pyrimidinone derivatives in good yields, with excellent diastereoselectivity. This method has various benefits such as easy availability of starting materials, lower cost, higher yield and shorter reaction time. Component (thermodynamics) ; Catalysis ; Combinatorial chemistry ; Chemistry ; Organic chemistry ; Physics Multicomponent Synthesis of Heterocycles ; Synthesis and biological activity ; Synthesis of Organic Compounds
Authors: Rezaul Haque Ansary | Tomal Chandro Roy | Ali Asraf | Sabina Easmin
Source: American Journal of Nano Research and Applications (article, 2020-01-01)
Field: Materials Science — Biomaterials

Preparation, Characterization and Antifungal Activity Studies of AgNPs Loaded Silk Fibroin Hydrogels Silk fibroin hydrogels are promising materials for controlled drug delivery device due to their aqueous process ability, biocompatibility, and biodegradability. The research work is aimed to prepare silk fibroin (SF) hydrogels loaded with Ag nanoparticles and to evaluate its antifungal activities. The Silk fibroin hydrogels were formulated at 37°C using 2% (w/v) silk fibroin aqueous solution either by treating 50% (v/v) of ethanol, or 50% (v/v) of propanol, or 50% (v/v) of glycerol, respectively. Above these, the rate of gelation was sufficiently accelerated by addition of glycerol. The silk fibroin hydrogels and prepared silver nanoparticles (AgNPs) were characterized by using Scanning Electron Microscopy (SEM), Thermo Gravimetrical Analysis (TGA). The encapsulation efficiency and release profile of AgNPs were studied by UV-vis spectrometry. The particle size of AgNPs was measured by Malvern Zetasizer Nano and found 93±5 nm. The encapsulation efficiency and morphology of the hydrogels was affected by the formulation conditions. The <i>in vitro</i> release profile showed an initial burst release of AgNPs followed by controlled release for next 20 hours. The antifungal activity of AgNPs loaded SF hydrogels showed a positive response to <i>Aspergillus Niger</i> pathogen. Therefore, silk fibroin hydrogels might be an effective biopolymeric matrix for antifungal applications. Fibroin ; Self-healing hydrogels ; Biocompatibility ; Aqueous solution ; Controlled release ; Chemical engineering ; Silver nanoparticle ; SILK ; Chemistry ; Nuclear chemistry ; Materials science ; Nanoparticle ; Polymer chemistry ; Nanotechnology ; Organic chemistry ; Composite material Silk-based biomaterials and applications ; Biochemical and Structural Characterization ; Polymer Surface Interaction Studies
Authors: Leiming Zhu | Leonard Himmel | Jean Michél Merkes | Fabian Kießling | Magnus Rueping | Srinivas Banala
Source: Chemistry - A European Journal (article, 2020-01-15)
Field: Chemistry — Organic Chemistry

Atropisomers of <i>meso</i> Tetra(<i>N</i>‐Mesyl Pyrrol‐2‐yl) Porphyrins: Synthesis, Isolation and Characterization of All‐Pyrrolic Porphyrins Atropisomerism has been observed in a variety of biaryl compounds and meso-aryl substituted porphyrins. However, in porphyrins, this phenomenon had been shown only with o-substituted 6-membered aromatic groups at the meso-position. We show herein that a 5-membered heteroaromatic (N-mesyl-pyrrol-2-yl) group at the meso-position leads to atropisomerism. In addition, we report a 'one-pot' synthetic route for the synthesis of 'all-pyrrolic' porphyrin (APP) with several N-protection groups (Boc, Cbz, Ms and Ts). Among these groups, we found that only the Ms group gave four individually separable atropisomers of meso-tetra(N-Ms-pyrrol-2-yl) porphyrin. Furthermore, the reductive removal of Cbz- was achieved to obtain meso-tetra(pyrrol-2-yl) porphyrin. Thus, our synthetic procedure provides an easy access to a group of APPs and stable atropisomers, which is expected to expand the application of novel APP-based materials. Atropisomer ; Porphyrin ; Chemistry ; Tetra ; Aryl ; Stereochemistry ; Combinatorial chemistry ; Medicinal chemistry ; Organic chemistry Axial and Atropisomeric Chirality Synthesis ; Porphyrin and Phthalocyanine Chemistry ; Synthesis and Properties of Aromatic Compounds
Authors: Athira Suku | J. Ashtami | P.V. Mohanan | C De Nada | A Mirone | S Dhesi | P Bencok | N Brookes | I Marenne | P Rudolf | N Tagmatarchis | H Shinohara | T Dennis | S Singh | V Gupta | P Probst | F Goler | A Steiner | J Schubert | Y Brasse | T Konig | A Fery | I Iavicoli | V Leso | W Ricciardi | L Hodson | M Hoover | K Beumer | W Krtschmer | L Lamb | K Fostiropoulos | D Huffman | S Rousseva | H Besten | F Van Kooij | E Doting | N Doumon | E Douvogianni | Anton Koster | L Hummelen | J | H Kroto | J Heath | S ;''o'brien | R Curl | R Smalley | N Man | Y Nagano | T Kiyobayashi | M Sakiyama | S Athira | T Biby | P Mohanan | E Biby | L Becker | J Bada | R Winans | J Hunt | T Bunch | B French | L Dugan | E Lovett | K Quick | J Lotharius | T Lin | ' Malley | O' Malley | K Malley | J Ashtami | S Anju | N Prajitha | K Rajeev | D Sakthikumar | T Maekawa | A Tykhomyrov | V Nedzvetsky | V Klochkov | G Andrievsky | E Nakamura | H Isobe | A Isakovic | Z Markovic | B Todorovic-Markovic | N Nikolic | S Vranjes-Djuric | M Mirkovic | M Dramicanin | L Harhaji
Source: Letters in Applied NanoBioScience (article, 2020-08-19)
Field: Chemistry — Organic Chemistry

Glial Cell Colony Injured on Exposure to Fullerene Soot Nanoparticles An expansion in the field of nanotechnology and their applications in medicine and pharmaceuticals have revolutionized the 20th century. Principally it deals with particles exhibiting a size below 100nm at least in a single dimension. Various fields that gain application potentials of nanotechnology include health and medicine, electronics, energy and environment, space research, etc. Advancements in experimental techniques have to lead to the development of multi functionalized nanoparticles like fullerenes, which is one of the allotropic forms of carbon. Fullerene was initially fabricated by laser ablation of graphite in an inert atmosphere. The crude early form consists of a mixture of interlocked carbon cages in its impure version, referred to as fullerene soot. Nature gets exposed to fullerene soot from a cluster of sources, including vehicle, industrial, and other household exhausts. An increasing level of exposure requires toxicity evaluation of such materials in biological systems. Present study addresses in vitro toxicity studies of fullerene soot nanoparticles in C6 glial cells. The study particularly analyzes cell viability assays, morphological evaluations, organelle functionality analysis, live-dead assays, and nuclear integrity measurement. The study confirms the dose-dependent toxicity of the nanomaterials, which further recommends proper precautions to be taken during exposure occasions. Fullerene ; Soot ; Nanotechnology ; Nanoparticle ; Nanomaterials ; Graphite ; Materials science ; Carbon fibers ; Nanotoxicology ; Combustion ; Chemistry ; Organic chemistry ; Composite material ; Composite number Fullerene Chemistry and Applications ; Carbon Nanotubes in Composites ; Nanoparticles: synthesis and applications
Authors: Iman Adipurnama | Ming Yang | Tomasz Ciach | Beata Butruk Raszeja
Source: Jurnal Bahan Alam Terbarukan (review, 2020-06-16)
Field: Materials Science — Biomaterials

Surface Modification With Gelatin For Polyurethane Vascular Grafts: A Review The means for developing synthetic vascular grafts to replace blood vessels is increasing extensively because of the limited supply of autologous vessels. Synthetic polymers as the alternatives still suffer from restenosis and thrombus formation. Natural polymers, on the other hand, are commonly biocompatible and biodegradable, compliment the synthetic ones. Blending, grafting and coating of natural polymers have been proposed to improve surface properties of synthetic polymers. Gelatin is a promising candidate to help improving synthetic vascular grafts surface owing to its ability to promote cell adhesion without promoting platelet aggregation at its surface. In this review, several techniques to incorporate gelatin onto synthetic polymers, mainly polyurethane, for vascular grafts application are summarized, together with the recent updates and potential development in the future. Polyurethane ; Gelatin ; Materials science ; Synthetic polymer ; Polymer ; Surface modification ; Natural polymers ; Biocompatible material ; Coating ; Grafting ; Biomedical engineering ; Adhesion ; Nanotechnology ; Chemical engineering ; Composite material ; Chemistry ; Medicine ; Organic chemistry Electrospun Nanofibers in Biomedical Applications ; Infectious Aortic and Vascular Conditions ; Polymer Surface Interaction Studies
Authors: Ana-Mihaela Gavrilă | Tanta‐Verona Iordache | Catherine Branger | Hugues Brisset | Katri Laatikainen | Ana Lorena Ciurlică | Anamaria Zaharia | Anita Laura Radu | Alina Elena Coman | Simona Flor | Andrei Sârbu
Source: Materiale Plastice (article, 2020-04-17)
Field: Chemistry — Spectroscopy

The Effect of Monomers on the Recognition Properties of Molecularly Imprinted Beads for Proto-hypericin and Proto-pseudohypericin Molecularly imprinted polymer (MIP) beads for proto-hypericin recognition were prepared by suspension polymerization. In order to study the impact of monomers on the MIPs properties, various monomers such as acrylic acid (AA), hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA) and itaconic acid (IA) in their combinations were crosslinked with ethylene glycol dimethacrylate (EDMA) in the presence of a complex phyto-extract template derived from Hypericum perforatum L. The synthesized MIPs and corresponding non-imprinted polymers NIPs were characterized by infrared spectroscopy analysis, morphology and thermogravimetric analysis. High-performance liquid chromatography combined with UV-Visible spectroscopy, used to investigate the recognition properties of the MIPs for various naphthodianthrones, pointed out that the MIP IA-AA system seemed to be the most adequate for favoring quantitative rebinding of proto-hypericin and proto-pseudohypericin against competitors with similar structures, like hypericin and pseudo-hypericin, which are usually present in high quantities in the primary Hypericum perforatum L. phyto-extracts. Hypericin ; Molecularly imprinted polymer ; Hypericum perforatum ; Ethylene glycol dimethacrylate ; Methacrylic acid ; Polymerization ; Chemistry ; Monomer ; Polymer ; Methacrylate ; Chromatography ; Nuclear chemistry ; Organic chemistry ; Selectivity ; Traditional medicine Analytical Chemistry and Chromatography ; Analytical chemistry methods development ; Lichen and fungal ecology
Authors: Thomas Weinbender | Michael Knierbein | Lukas Bittorf | Christoph Held | Riko Siewert | Sergey P. Verevkin | Gabriele Sadowski | Oliver Reiser
Source: ChemPlusChem (article, 2020-06-01)
Field: Chemistry — Spectroscopy

High‐Pressure‐Mediated Thiourea‐Organocatalyzed Asymmetric Michael Addition to (Hetero)aromatic Nitroolefins: Prediction of Reaction Parameters by PCP‐SAFT Modelling Thiourea-organocatalyzed Michael additions of diethyl malonate to various heteroaromatic nitroolefins (13 examples) have been studied under high-pressure (up to 800 MPa) and ambient pressure conditions. High pressure was conducive to enhanced product yields by a factor of 2-12 at a given reaction time, high reaction rates (reaction times were decreased from 72-24 h down to 4-24 h) and high enantioselectivity. Elucidating the effects of solvents for maximizing reaction rates and yields has been carried out using the Perturbed-Chain Polar Statistical Associating Fluid Theory (PCP-SAFT), allowing for the first time a prediction of the kinetic profiles under high-hydrostatic-pressure conditions. Diethyl malonate ; Michael reaction ; Chemistry ; Thiourea ; High pressure ; Hydrostatic pressure ; Organic chemistry ; Thermodynamics ; Computational chemistry ; Catalysis Analytical Chemistry and Chromatography ; Ionic liquids properties and applications ; Crystallization and Solubility Studies