jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Valeria Castelletto | Charlotte J. C. Edwards‐Gayle | Ian W. Hamley | Juliane N. B. D. Pelin | Wendel A. Alves | Andrea M. Aguilar | Jani Seitsonen | Janne Ruokolainen
Source: ACS Applied Bio Materials (article, 2019-07-03)
Field: Materials Science — Biomaterials

Self-Assembly of a Catalytically Active Lipopeptide and Its Incorporation into Cubosomes The self-assembly and biocatalytic activity of the proline-functionalized lipopeptide PRW-NH-C<sub>16</sub> are examined and compared to that of the related PRW-O-C<sub>16</sub> lipopeptide, which differs in having an ester linker between the lipid chain and tripeptide headgroup instead of an amide linker. Lipopeptide PRW-NH-C<sub>16</sub> self-assembles into spherical micelles above a critical aggregation concentration, similar to the behavior of PRW-O-C<sub>16</sub> reported previously [B. M. Soares et al. <i>Phys. Chem. Chem. Phys.</i>, 2017, 19, 1181-1189]. However, PRW-NH-C<sub>16</sub> shows an improved catalytic activity in a model aldol reaction. In addition, we explore the incorporation of the biocatalytic lipopeptide into lipid cubosomes. SAXS shows that increasing lipopeptide concentration leads to an expansion of the monoolein cubosome lattice spacing and a loss of long-range cubic order as the lipopeptide is encapsulated in the cubosomes. At higher loadings of lipopeptide, reduced cubosome formation is observed at the expense of vesicle formation. Our results show that the peptide-lipid chain linker does not influence self-assembly but does impart an improved biocatalytic activity. Furthermore, we show that lipopeptides can be incorporated into lipid cubosomes, leading to restructuring into vesicles at high loadings. These findings point the way toward the future development of bioactive lipopeptide assemblies and slow release cubosome-based delivery systems. Lipopeptide ; Chemistry ; Linker ; Surfactin ; Combinatorial chemistry ; Stereochemistry ; Biophysics ; Bacillus subtilis ; Bacteria Supramolecular Self-Assembly in Materials ; Lipid Membrane Structure and Behavior ; RNA Interference and Gene Delivery
Authors: Zhaoqi Ye | Hongbin Zhang | Yahong Zhang | Yi Tang
Source: Frontiers of Chemical Science and Engineering (article, 2019-11-29)
Field: Chemistry — Inorganic Chemistry

Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms, and catalytic properties Zeolite ; Crystallization ; Template ; Catalysis ; Materials science ; Chemical engineering ; Function (biology) ; Nanotechnology ; Chemistry ; Organic chemistry ; Biology ; Engineering Zeolite Catalysis and Synthesis ; Covalent Organic Framework Applications ; Mesoporous Materials and Catalysis
Authors: Julian Chojnowski | Stanisław Słomkowski | Witold Fortuniak | Urszula Mizerska | Piotr Pośpiech
Source: Journal of Inorganic and Organometallic Polymers and Materials (article, 2019-10-25)
Field: Materials Science — Ceramics and Composites

Hydrophilic Polysiloxane Microspheres and Ceramic SiOC Microspheres Derived from Them Abstract In this overview article, the research on polysiloxane microspheres performed in the authors’ laboratory is briefly reviewed. These microspheres are prepared in water emulsion from polyhydromethylsiloxane (PHMS). This polymer is cross-linked in the emulsion process by hydrosilylation using various low molecular weight cross-linkers having at least two vinyl functions. The microspheres contain a large number of silanol groups which give them hydrophilicity and a broad possibility of functionalization by condensation with reactive silanes bearing a functional group in the organic radical. Further transformation of these functions leads to materials for practical use, such as catalysts and biocidal powders. The hydrophilic-hydrophobic properties of the microspheres may be fine-tuned by silylation or modification of the precursor PHMS polymer. Pristine microspheres are highly hydrophilic and well-dispersed in water. They do not adsorb proteins and hydrophobic organic substances. Macropores may be generated in these particles by a simple modification of the emulsion procedure. These microspheres are also very good precursors for ceramic silicon oxycarbide microsphers because they retain their shape in pyrolytic processes even at high temperatures; and they give a high yield of ceramic material. The polysiloxane microspheres heated at 600 °C give micro and mezo porous materials with specific surface above 500 m 2 /g. When pyrolysed at temperatures 1000–1400 °C, they form solid ceramic microspheres of high strength. They retain spherical shape at 1500 °C although cracks are formed at their surfaces. Etching them with HF(aq) solution gives porous microspheres with specific surface above 1000 m 2 /g that is almost devoid of SiO 2 . Materials science ; Silanol ; Surface modification ; Ceramic ; Chemical engineering ; Emulsion ; Polymer ; Hydrosilylation ; Methyltrimethoxysilane ; Silanization ; Adsorption ; Microsphere ; Polymer chemistry ; Silanes ; Composite material ; Organic chemistry ; Catalysis ; Silane ; Chemistry ; Coating Advanced ceramic materials synthesis ; Silicone and Siloxane Chemistry ; Electrospun Nanofibers in Biomedical Applications
Authors: Vincent Jalaber | Doriane Del Frari | Julien De Winter | Kahina Mehennaoui | Sébastien Planchon | Patrick Choquet | Christophe Detrembleur | Maryline Moreno‐Couranjou
Source: Frontiers in Chemistry (article, 2019-04-02)
Field: Materials Science — Surfaces, Coatings and Films

Atmospheric Aerosol Assisted Pulsed Plasma Polymerization: An Environmentally Friendly Technique for Tunable Catechol-Bearing Thin Films In this work, an atmospheric aerosol assisted pulsed plasma process is reported as an environmentally friendly technique for the preparation of tunable catechol-bearing thin films under solvent and catalyst free conditions. The approach relies on the direct injection of dopamine acrylamide dissolved in 2-hydroxyethylmethacrylate as comonomer into the plasma zone. By adjusting the pulsing of the electrical discharge, the reactive plasma process can be alternatively switch ON (t<sub>ON</sub>) and OFF (t<sub>OFF</sub>) during different periods of time, thus allowing a facile and fine tuning of the catechol density, morphology and deposition rate of the coating. An optimal t<sub>ON</sub>/t<sub>OFF</sub> ratio is established, that permits maximizing the catechol content in the deposited film. Finally, a diagram, based on the average energy input into the process, is proposed allowing for easy custom synthesis of layers with specific chemical and physical properties, thus highlighting the utility of the developed dry plasma route. Comonomer ; Catechol ; Environmentally friendly ; Plasma ; Materials science ; Chemical engineering ; Aerosol ; Polymerization ; Atmospheric-pressure plasma ; Coating ; Thin film ; Chemistry ; Nanotechnology ; Composite material ; Organic chemistry ; Polymer Surface Modification and Superhydrophobicity ; Diamond and Carbon-based Materials Research ; Graphene research and applications
Authors: Han Song | Gil Ju Lee | Dong Eun Yoo | Yeong Jae Kim | Young Jin Yoo | Dongwook Lee | Vantari Siva | Il‐Suk Kang | Young Min Song
Source: Scientific Reports (article, 2019-03-04)
Field: Materials Science — Surfaces, Coatings and Films

Reflective color filter with precise control of the color coordinate achieved by stacking silicon nanowire arrays onto ultrathin optical coatings The engineering of structural colors is currently a promising, rapidly emerging research field because structural colors of outstanding spatial resolution and durability can be generated using a sustainable production method. However, the restricted and saturated color range in micro/nano-fabricated structural 'pigments' has hindered the dissemination of structural color printing. Here, this article presents a spectral mixing color filter (SMCF), which is the concept of fine-tunable color systems, capable of addressing the current issues in structural color engineering, by stacking a vertical silicon nanowire array embedded in a transparent polymer onto ultrathin optical coating layers. These two photonic structures enable independent tuning the optical resonance of each structure, depending on geometrical parameters, such as the diameter of nanowires and thickness of absorbing medium. Hence, the SMCF facilitates the linear combination of two resonant spectra, thereby enabling fine-tuning and widening of the color gamut. Theoretical studies and experimental results reveal the detailed working mechanisms and extraordinary mechanical feature of the SMCF. Based on the analyses, the concept of flexible optical device, e.g., a reflective anti-counterfeiting sticker, is demonstrated. Successful characterization demonstrates that the proposed strategy can promote the color controllability/purity of structural color and the applicability as flexible optical device. Stacking ; Color gel ; Filter (signal processing) ; Materials science ; Optical filter ; Silicon ; Nanowire ; Silicon nanowires ; Optoelectronics ; Color filter array ; Optics ; Computer science ; Nanotechnology ; Layer (electronics) ; Computer vision ; Chemistry ; Physics Optical Coatings and Gratings ; Photonic Crystals and Applications ; Plasmonic and Surface Plasmon Research
Authors: Samrat Ghosh | Akinobu Nakada | Maximilian A. Springer | Takahiro Kawaguchi | Katsuaki Suzuki | Hironori Kaji | Igor A. Baburin | Agnieszka Kuc | Thomas Heine | Ryu Abe | Shu Seki
Source: ChemRxiv (preprint, 2019-07-22)
Field: Materials Science — Materials Chemistry

Identification of Prime Factors to Maximize the Photocatalytic Hydrogen Evolution of Covalent Organic Frameworks &lt;div&gt;Visible light driven hydrogen (H2) production from water is a promising strategy to convert and store solar energy as chemical energy. Covalent organic frameworks (COFs) are front runners among different classes of organic photocatalyst, owing to their tunable porosity, crystallinity, optical and electronic properties. Photocatalytic activity of COFs depends on numerous factors such as band gap, crystallinity, porosity, exciton migration, charge separation and transport, stability etc. However, it is challenging to fine tune all these factors simultaneously to enhance the photocatalytic activity. Hence, in this report, we have prioritized the key factors for efficient photocatalytic H2 production through structure–property–activity relationship combined with microwave spectroscopy and first–principles calculations. Careful molecular engineering allowed us to tune the light absorption (i.e. band gap), crystallinity, porosity, layer stacking and charge carrier generation and transport of a series of isoreticular COFs. We have assessed how these properties and the interplay between them impact photocatalytic activity of studied COFs. From the structure–property–activity relationship, we found that light absorption and charge carrier generation and transport are the prime factors, which influence the photocatalytic H2 production of COFs in much greater extent than other factors.&lt;/div&gt; Photocatalysis ; Crystallinity ; Materials science ; Hydrogen production ; Absorption (acoustics) ; Band gap ; Stacking ; Porosity ; Covalent bond ; Charge carrier ; Chemical engineering ; Nanotechnology ; Photochemistry ; Hydrogen ; Optoelectronics ; Chemistry ; Catalysis ; Composite material ; Organic chemistry Covalent Organic Framework Applications ; Advanced Photocatalysis Techniques ; Catalytic Processes in Materials Science
Authors: Qiaobei Dong | Zhuonan Song | Fanglei Zhou | Huazheng Li | Miao Yu
Source: Microporous and Mesoporous Materials (article, 2019-02-27)
Field: Materials Science — Materials Chemistry

Ultrathin, fine-tuned microporous coating modified 5A zeolite for propane/propylene adsorptive separation Propane ; Zeolite ; Microporous material ; Adsorption ; Chemical engineering ; Materials science ; Coating ; Molecular sieve ; Propene ; Chemistry ; Organic chemistry ; Catalysis ; Nanotechnology ; Composite material Catalytic Processes in Materials Science ; Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis
Authors: H L Pradeepa | Praloy Mondal | Aveek Bid | J. K. Basu
Source: ACS Applied Nano Materials (article, 2019-12-24)
Field: Materials Science — Materials Chemistry

Electrical and Chemical Tuning of Exciton Lifetime in Monolayer MoS<sub>2</sub> for Field-Effect Transistors We report the room temperature tuning of excitonic lifetime in pristine and hole-doped monolayer MoS2 based field effect transistor (FET) devices by systematically controlling the free carrier density. We observed that in pristine MoS2 devices, with intrinsic electron doping, an exciton dominant regime with an exciton lifetime of 3 ns exists, when doped electrostatically with holes. Interestingly we observe a sharp decrease in exciton lifetime and population with an increase of the electron density by electrostatic doping, with a corresponding increase in negative trion population. With increased hole doping by a chemical method, the exciton lifetime decreases, but it remains almost constant with electrostatic carrier density tuning. This decrease in lifetime, compared to that of the pristine case, might be due to the exciton–exciton annihilation mechanism which is proposed to be existent in a high exciton density regime. Further hole doping by a chemical method leads to a transition to a positive trion dominated regime, in which the exciton lifetime decreases further due to nonradiative energy transfer to the positive trions. We observe a slight increase in exciton lifetime due to partial neutralization of positive trions at high electrostatic electron doping and a corresponding increase in the probability of excitons. We suggest that when calculating the lifetime of excitons, the exciton-to-trions formation and exciton–exciton annihilation mechanisms should be considered. These fine-tunings of excitons in monolayer MoS2 can provide a platform for probing the excitonic physics and photonic applications. Trion ; Exciton ; Doping ; Biexciton ; Monolayer ; Condensed matter physics ; Electron ; Materials science ; Annihilation ; Population ; Physics ; Nanotechnology 2D Materials and Applications ; Perovskite Materials and Applications ; MXene and MAX Phase Materials
Authors: Assem Barakat | Fardous F. El‐Senduny | Zainab M. Almarhoon | Hessa H. Al‐Rasheed | Farid A. Badria | Abdullah Mohammed Al‐Majid | Hazem A. Ghabbour | Ayman El‐Faham
Source: Journal of Chemistry (article, 2019-04-30)
Field: Chemistry — Organic Chemistry

Synthesis, X-Ray Crystal Structures, and Preliminary Antiproliferative Activities of New s-Triazine-hydroxybenzylidene Hydrazone Derivatives We herein report a new small library of Schiff-base compounds that encompasses s-triazine and (2 or 4)-hydroxylbenzylidene derivatives. These compounds were synthesized through a hydrazone linkage connecting both the s-triazine and hydroxybenzylidene derivatives. The synthetic strategy adopted allowed the synthesis of the target compounds with excellent yields and purities as observed from their NMR ( 1 H and 13 C) and elemental analysis. Furthermore, 4f , 5b , and 5f were further confirmed by X-ray single crystal diffraction technique. The preliminary antiproliferative activities for the synthesized compounds were tested against two different cancer cell lines including breast cancer (MCF-7) and colon cancer (HCT-116). From the eighteen compounds, which have been examined, only two derivatives having piperidine moiety showed more selectivity against the two cell lines MCF-7 and HCT-116, while the others showed very weak activity. The position of the hydroxyl group in the benzylidine ring and the substituent on the s-triazine moiety has great effect on the activity of the prepared compounds. The IC 50 values for the two derivatives 4a and 5a evaluated against breast cancer cells, very close to those for the chemotherapeutic drug cisplatin, are 27 µ M (13.3 µ g/mL), 17 µ M (8.4 µ g/mL), and 20 µ M (6 µ g/mL) for 4a , 5a , and cisplatin, respectively. These results propose the preliminary antiproliferative activity of these two derivatives may deserve further consideration for development of new derivatives as potent anticancer agents. Chemistry ; Moiety ; Hydrazone ; Substituent ; Triazine ; Cisplatin ; Stereochemistry ; Schiff base ; Combinatorial chemistry ; Coumarin ; Piperidine ; Organic chemistry Synthesis and Characterization of Heterocyclic Compounds ; Synthesis of Tetrazole Derivatives ; Synthesis and biological activity
Authors: Venkata Deepthi Vemuri | Srinivas Lankalapalli
Source: Indian Journal of Pharmaceutical Education and Research (article, 2019-11-11)
Field: Materials Science — Materials Chemistry

Insight into Concept and Progress on Pharmaceutical Co-Crystals: An overview Pharmaceutical co-crystals have conferred significant recognition in recent past as a new solid form by virtue their capability to modulate physicochemical properties of Active Pharmaceutical Ingredient (API). Nevertheless, pharmaceutical progress of cocrystals could be provocation, the requirement for high-throughput screening methods and the techniques capable of co-crystal production in industrial scale still hamper the co-crystal used by industries. In this review, well ordered overview of pharmaceutical co-crystal is provided, with focus on role of supramolecular chemistry, co-crystal design strategies, preparation methods, physicochemical property studies, mechanism of solubility enhancement, evaluation techniques. In the present commentary, the impact of choosing appropriate process design and formulation on translational challenges has been discussed. Eventually, a short outline of applications and marketed drug products of pharmaceutical co-crystal drug substance is also described. Active ingredient ; Crystal engineering ; Pharmaceutical industry ; Crystallization ; Nanotechnology ; Biochemical engineering ; Crystal (programming language) ; Materials science ; Supramolecular chemistry ; Pharmaceutical drug ; Chemistry ; Drug ; Combinatorial chemistry ; Computer science ; Organic chemistry ; Crystal structure ; Pharmacology ; Medicine ; Engineering Crystallization and Solubility Studies ; Crystallography and molecular interactions ; Drug Solubulity and Delivery Systems
Authors: Andrea Porcheddu | Francesco Delogu | Lidia De Luca | Claudia Fattuoni | Evelina Colacino
Source: Beilstein Journal of Organic Chemistry (article, 2019-07-25)
Field: Chemistry — Organic Chemistry

Metal-free mechanochemical oxidations in Ertalyte<sup>®</sup> jars Aimed at eliminating or at least significantly reducing the use of solvents, sodium hypochlorite pentahydrate crystals (NaOCl·5H<sub>2</sub>O) in the presence of a catalytic amount of a nitrosyl radical (TEMPO or AZADO) have been successfully used to induce mechanochemical oxidative processes on several structurally different primary and secondary alcohols. The proposed redox process is safe, inexpensive and performing effectively, especially on the macroscale. Herein, an Ertalyte<sup>®</sup> jar has been successfully used, for the first time, in a mechanochemical process. Chemistry ; Sodium hypochlorite ; Mechanochemistry ; Catalysis ; Redox ; Metal ; Primary (astronomy) ; Chemical engineering ; Combinatorial chemistry ; Inorganic chemistry ; Organic chemistry ; Nuclear chemistry Oxidative Organic Chemistry Reactions ; Catalysis and Oxidation Reactions ; Mesoporous Materials and Catalysis
Authors: Albert Cabré | Elia Romagnoli | Pol Martínez-Balart | Xavier Verdaguer | Antoni Riéra
Source: Organic Letters (article, 2019-11-08)
Field: Chemistry — Inorganic Chemistry

Highly Enantioselective Iridium-Catalyzed Hydrogenation of 2-Aryl Allyl Phthalimides The iridium-catalyzed asymmetric hydrogenation of 2-aryl allyl phthalimides to afford enantioenriched β-aryl-β-methyl amines is presented. Recently developed Ir-MaxPHOX catalysts are used for this enantioselective transformation. The mild reaction conditions and the feasible removal of the phthalimido group makes this catalytic method easily scalable and of great interest to afford chiral amines. The importance of this new methodology is exemplified by the formal synthesis of (<i>R</i>)-Lorcaserin, OTS514, and enantiomerically enriched 3-methyl indolines. Phthalimides ; Iridium ; Enantioselective synthesis ; Chemistry ; Catalysis ; Aryl ; Combinatorial chemistry ; Organic chemistry ; Phthalimide ; Alkyl Asymmetric Hydrogenation and Catalysis ; Advanced Synthetic Organic Chemistry ; Asymmetric Synthesis and Catalysis
Authors: Hongyan Xu | Feng Han | Chengkai Xia | Siyan Wang | Ranish M. Ramachandran | Christophe Detavernier | Minsong Wei | Liwei Lin | Serge Zhuiykov
Source: Nanoscale Research Letters (article, 2019-05-14)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Wafer-Scale Fabrication of Sub-10 nm TiO2-Ga2O3 n-p Heterojunctions with Efficient Photocatalytic Activity by Atomic Layer Deposition Wafer-scale, conformal, two-dimensional (2D) TiO<sub>2</sub>-Ga<sub>2</sub>O<sub>3</sub> n-p heterostructures with a thickness of less than 10 nm were fabricated on the Si/SiO<sub>2</sub> substrates by the atomic layer deposition (ALD) technique for the first time with subsequent post-deposition annealing at a temperature of 250 °C. The best deposition parameters were established. The structure and morphology of 2D TiO<sub>2</sub>-Ga<sub>2</sub>O<sub>3</sub> n-p heterostructures were characterized by the scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), etc. 2D TiO<sub>2</sub>-Ga<sub>2</sub>O<sub>3</sub> n-p heterostructures demonstrated efficient photocatalytic activity towards methyl orange (MO) degradation at the UV light (λ = 254 nm) irradiation. The improvement of TiO<sub>2</sub>-Ga<sub>2</sub>O<sub>3</sub> n-p heterostructure capabilities is due to the development of the defects on Ga<sub>2</sub>O<sub>3</sub>-TiO<sub>2</sub> interface, which were able to trap electrons faster. Heterojunction ; X-ray photoelectron spectroscopy ; Materials science ; Atomic layer deposition ; Photocatalysis ; Wafer ; Methyl orange ; Dielectric spectroscopy ; Scanning electron microscope ; Annealing (glass) ; Nanotechnology ; Nanochemistry ; Layer (electronics) ; Optoelectronics ; Chemical engineering ; Analytical Chemistry (journal) ; Electrochemistry ; Chemistry ; Composite material ; Electrode ; Catalysis Ga2O3 and related materials ; Advanced Photocatalysis Techniques ; ZnO doping and properties