jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Mukkath Joseph Josline | Eui‐Tae Kim | Jae‐Hyun Lee
Source: Applied Science and Convergence Technology (article, 2022-05-30)
Field: Materials Science — Materials Chemistry

Recent Advances in the Low-Temperature Chemical Vapor Deposition Growth of Graphene Since the realization of the prospect of synthesizing graphene via mechanical exfoliation, graphene has garnered considerable attention owing to its remarkable chemical, electrical, material, and various other properties, which makes it an ideal contender for electronic and optoelectronic applications. Many top-down and bottom-up strategies have been researched to fabricate graphene films, notably chemical vapor deposition (CVD), which has been proven to deliver large-area, high-quality graphene films with the additional advantage of being economical. However, graphene production utilizing gaseous predecessors, such as methane, typically requires high temperatures, which increases the production cost due to the high thermal budget. Recently, the prospect of employing low-temperature conditions for graphene growth has been explored, using various hydrocarbon precursors and alternative energy sources. This review discusses the low-temperature CVD growth of graphene and recent improvements in this area with a brief introduction to applications based on these graphene specimens. Graphene ; Chemical vapor deposition ; Materials science ; Nanotechnology ; Deposition (geology) ; Chemical engineering ; Chemistry ; Biology ; Engineering Graphene research and applications ; Carbon Nanotubes in Composites ; Thermal properties of materials
Authors: Naomi M. Hamelmann | Sjoerd Uijttewaal | Sry D. Hujaya | Jos M. J. Paulusse
Source: Biomacromolecules (article, 2022-11-16)
Field: Materials Science — Biomaterials

Enhancing Cellular Internalization of Single-Chain Polymer Nanoparticles via Polyplex Formation Intracellular delivery of nanoparticles is crucial in nanomedicine to reach optimal delivery of therapeutics and imaging agents. Single-chain polymer nanoparticles (SCNPs) are an interesting class of nanoparticles due to their unique site range of 5-20 nm. The intracellular delivery of SCNPs can be enhanced by using delivery agents. Here, a positive polymer is used to form polyplexes with SCNPs, similar to the strategy of protein and gene delivery. The size and surface charge of the polyplexes were evaluated. The cellular uptake showed rapid uptake of SCNPs via polyplex formation, and the cytosolic delivery of the SCNPs was presented by confocal microscopy. The ability of SCNPs to act as nanocarriers was further explored by conjugation of doxorubicin. Nanocarriers ; Internalization ; Nanoparticle ; Nanomedicine ; Chemistry ; Intracellular ; Biophysics ; Drug delivery ; Nanotechnology ; Polymer ; Confocal microscopy ; Gene delivery ; Materials science ; Cell biology ; Biochemistry ; Transfection ; Cell ; Organic chemistry Nanoparticle-Based Drug Delivery ; RNA Interference and Gene Delivery ; Advanced Polymer Synthesis and Characterization
Authors: Fabiana M. Pennisi | Anna Lucia Pellegrino | Nadia Licciardello | Claudia Mezzalira | Massimo Sgarzi | Adolfo Speghini | Graziella Malandrino | Gianaurelio Cuniberti
Source: Scientific Reports (article, 2022-08-12)
Field: Materials Science — Materials Chemistry

Synthesis, characterization and photocatalytic properties of nanostructured lanthanide doped β-NaYF4/TiO2 composite films The photocatalytic approach is known to be one of the most promising advanced oxidation processes for the tertiary treatment of polluted water. In this paper, β-NaYF<sub>4</sub>/TiO<sub>2</sub> composite films have been synthetized through a novel sol-gel/spin-coating approach using a mixture of β-diketonate complexes of Na and Y, and Yb<sup>3+</sup>, Tm<sup>3+</sup>, Gd<sup>3+</sup>, Eu<sup>3+</sup> as doping ions, together with the TiO<sub>2</sub> P25 nanoparticles. The herein pioneering approach represents an easy, straightforward and industrially appealing method for the fabrication of doped β-NaYF<sub>4</sub>/TiO<sub>2</sub> composites. The effect of the doped β-NaYF<sub>4</sub> phase on the photocatalytic activity of TiO<sub>2</sub> for the degradation of methylene blue (MB) has been deeply investigated. In particular, the upconverting TiO<sub>2</sub>/β-NaYF<sub>4</sub>: 20%Yb, 2% Gd, x% Tm (x = 0.5 and 1%) and the downshifting TiO<sub>2</sub>/β-NaYF<sub>4</sub>: 10% Eu composite films have been tested on MB degradation both under UV and visible light irradiation. An improvement up to 42.4% in the degradation of MB has been observed for the TiO<sub>2</sub>/β-NaYF<sub>4</sub>: 10% Eu system after 240 min of UV irradiation. Photocatalysis ; Materials science ; Degradation (telecommunications) ; Doping ; Composite number ; Irradiation ; Lanthanide ; Methylene blue ; Chemical engineering ; Nanoparticle ; Coating ; Spin coating ; Visible spectrum ; Phase (matter) ; Nanotechnology ; Nuclear chemistry ; Photochemistry ; Ion ; Composite material ; Chemistry ; Catalysis ; Optoelectronics ; Organic chemistry ; Computer science Luminescence Properties of Advanced Materials ; Advanced Photocatalysis Techniques ; Inorganic Fluorides and Related Compounds
Authors: Sai Shradha Reddy Kommidi | Bradley D. Smith
Source: Molecules (article, 2022-08-25)
Field: Chemistry — Organic Chemistry

Cucurbit[7]uril Complexation of Near-Infrared Fluorescent Azobenzene-Cyanine Conjugates Two new azobenzene heptamethine cyanine conjugates exist as dispersed monomeric molecules in methanol solution and exhibit near-infrared (NIR) cyanine absorption and fluorescence. Both conjugates form non-emissive cyanine H-aggregates in water, but the addition of cucurbit[7]uril (CB7) induces dye deaggregation and a large increase in cyanine NIR fluorescence emission intensity. CB7 encapsulates the protonated azonium tautomer of the 4-(<i>N</i>,<i>N</i>-dimethylamino)azobenzene component of each azobenzene-cyanine conjugate and produces a distinctive new absorption band at 534 nm. The complex is quite hydrophilic, which suggests that CB7 can be used as a supramolecular additive to solubilize this new family of NIR azobenzene-cyanine conjugates for future biomedical applications. Since many azobenzene compounds are themselves potential drug candidates or theranostic agents, it should be possible to formulate many of them as CB7 inclusion complexes with improved solubility, stability, and pharmaceutical profile. Cyanine ; Azobenzene ; Chemistry ; Photochemistry ; Fluorescence ; Tautomer ; Protonation ; Conjugate ; Monomer ; Supramolecular chemistry ; Solubility ; Absorption (acoustics) ; Molecule ; Combinatorial chemistry ; Organic chemistry ; Polymer ; Materials science Supramolecular Chemistry and Complexes ; Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection
Authors: Agnideep Das | Jules Schleinitz | Lydia Karmazin | Bruno Vincent | Nolwenn Le Breton | Guillaume Rogez | Aurélie Guénet | Sylvie Choua | Laurence Grimaud | Marine Desage‐El Murr
Source: Chemistry - A European Journal (article, 2022-04-05)
Field: Chemistry — Organic Chemistry

A Single Bioinspired Hexameric Nickel Catechol–Alloxazine Catalyst Combines Metal and Radical Mechanisms for Alkene Hydrosilylation Mechanisms combining organic radicals and metallic intermediates hold strong potential in homogeneous catalysis. Such activation modes require careful optimization of two interconnected processes: one for the generation of radicals and one for their productive integration towards the final product. We report that a bioinspired polymetallic nickel complex can combine ligand- and metal-centered reactivities to perform fast hydrosilylation of alkenes under mild conditions through an unusual dual radical- and metal-based mechanism. This earth-abundant polymetallic complex incorporating a catechol-alloxazine motif as redox-active ligand operates at low catalyst loading (0.25 mol%) and generates silyl radicals and a nickel-hydride intermediate through a hydrogen atom transfer (HAT) step. Evidence of an isomerization sequence enabling terminal hydrosilylation of internal alkenes points towards the involvement of the nickel-hydride species in chain walking. This single catalyst promotes a hybrid pathway by combining synergistically ligand and metal participation in both inner- and outer- sphere processes. Hydrosilylation ; Chemistry ; Catalysis ; Nickel ; Hydride ; Radical ; Alkene ; Isomerization ; Photochemistry ; Ligand (biochemistry) ; Reductive elimination ; Metal ; Combinatorial chemistry ; Organic chemistry Radical Photochemical Reactions ; Catalytic C–H Functionalization Methods ; Sulfur-Based Synthesis Techniques
Authors: Satabdi Roy | Michael Böhme | Sudhir Lima | Monalisa Mohanty | Atanu Banerjee | Axel Buchholz | Winfried Plass | Sharan Shanmuga Vuppaladadium Rathnam | Indranil Banerjee | Werner Kaminsky | Rupam Dinda
Source: European Journal of Inorganic Chemistry (article, 2022-06-09)
Field: Chemistry — Inorganic Chemistry

Methoxido‐Bridged Lacunary Heterocubane Oxidovanadium(IV) Cluster with Azo Ligands: Synthesis, X‐ray Structure, Magnetic Properties, and Antiproliferative Activity Abstract The new μ 3 ‐methoxido bridged trinuclear vanadium(IV) complexes [V IV 3 O 3 (μ 3 ‐OMe)(μ 2 ‐OMe) 3 (L 1,2 ) 2 ] ( 1 and 2 ) have been synthesized using the azo ligands 1‐(2‐(thiazol‐2‐yl)diazenyl)naphthalene‐2‐ol (HL 1 ) and 2‐(2‐(thiazol‐2‐yl)diazenyl)‐4‐methylphenol (HL 2 ). X‐ray crystallography revealed a trinuclear structure with a lacunary heterocubane {(VO) 3 (μ 3 ‐OMe)(μ 2 ‐OMe) 3 } 2+ core unit for complex 1 , which contains a central μ 3 ‐methoxido bridge. All three vanadium centers are in a slightly distorted octahedral coordination environment. Magnetic and theoretical studies reveal an antiferromagnetic coupling between the three vanadium(IV) centers within the triangular arrangement in 1 . The complexes were also screened for in vitro cytotoxicity study against HeLa and HT‐29 cancer cell lines. The results indicated that both the complexes are cytotoxic but possess varying specificity towards different cell types. Lacunary function ; Chemistry ; Vanadium ; Octahedron ; Crystallography ; HeLa ; Stereochemistry ; 8-Hydroxyquinoline ; Antiferromagnetism ; Cytotoxicity ; Crystal structure ; In vitro ; Inorganic chemistry Vanadium and Halogenation Chemistry ; Magnetism in coordination complexes ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Joshua Nicks | Jonathan A. Foster
Source: Nanoscale (article, 2022-01-01)
Field: Chemistry — Inorganic Chemistry

Post-exfoliation functionalisation of metal–organic framework nanosheets <i>via</i> click chemistry The liquid exfoliation of layered metal-organic frameworks (MOFs) to form nanosheets (MONs) exposes buried functional groups making them useful in a range of sensing and catalytic applications. Here we show how high yielding click reactions can be used post-exfoliation to systematically modify the surface chemistry of MONs allowing for tuning of their surface properties and their use in new applications. A layered amino-functionalised framework is converted through conventional post-synthetic functionalisation of the bulk MOF to form azide functionalised frameworks of up to >99% yield. Ultrasonic liquid exfoliation is then used to form few-layer nanosheets, which are further functionalised through post exfoliation functionalisation using Cu(I)-catalysed azide-alkyne cycloaddition reactions. Here we demonstrate the advantages of post-exfoliation functionalisation in enabling: (1) a range of functional groups to be incorporated in high yields; (2) tuning of nanosheet surface properties without the need for extensive recharacterisation; (3) the addition of fluorescent functional groups to enable their use in the sensing of hazardous nitrobenzene. We anticipate that the versatility of different functional groups that can be introduced through high yielding click reactions will lead to advances in the use of MONs and other 2D materials for a variety of applications. Exfoliation joint ; Click chemistry ; Nanosheet ; Metal-organic framework ; Materials science ; Cycloaddition ; Nitrobenzene ; Nanotechnology ; Azide ; Nanoreactor ; Combinatorial chemistry ; Graphene ; Catalysis ; Chemistry ; Organic chemistry ; Polymer chemistry ; Nanoparticle Metal-Organic Frameworks: Synthesis and Applications ; 2D Materials and Applications ; Graphene research and applications
Authors: Janitha Jeewantha | Jayantha Epaarachchi‎ | Elizabeth Forster | Md Mainul Islam | Leng Jinsong
Source: eXPRESS Polymer Letters (article, 2022-01-01)
Field: Materials Science — Polymers and Plastics

Early research of shape memory polymer vascular stents Shape memory polymers (SMPs) are smart materials that can alter their shape from a temporary shape to a permanent shape upon external stimuli. This unique property of SMP has shown enormous potential and breakthrough discoveries in biomedical engineering. A significant number of SMP based research publications in the recent past have demonstrated the researchers' thirst to introduce SMP based devices to the biomedical fields. SMPs favour minimally invasive surgeries and showed enormous potential in vascular stents. However, SMP-based vascular stents have not been realised to date, indicating a lack of high-quality research outputs. Most studies either repeat or provide only minor extensions to ongoing research. This article reviews SMP materials used for vascular stent development and briefly introduces SMP, architecture, and history. Followed by SMP vascular stent fabrication methods, responsive physical behaviour, the performance of the vascular stents, limitations, and vitro and vivo clinical results. Finally, challenges and future directions of SMP vascular stents are identified and highlighted. Materials science ; Shape-memory polymer ; Polymer ; Polymer science ; Composite material Polymer composites and self-healing ; Marine Sponges and Natural Products ; Oxidative Organic Chemistry Reactions
Authors: Salomão Dos Santos Costa | Juliana Pereira da Silva | Matheus Moraes Biondo | Edgar Aparecido Sanches | Marcos Marques da Silva Paula | Francisco Xavier Nobre | José Anglada Rivera | Yohandys A. Zulueta | M. S. Torikachvili | D.V. Sampaio | Marcos Vinicius Dias Vermelho | Ştefan Ţălu | Lianet Aguilera Dominguez | Y. Leyet
Source: Molecules (article, 2022-09-06)
Field: Materials Science — Polymers and Plastics

Temperature Dependence of the Electrical Properties of Na2Ti3O7/Na2Ti6O13/POMA Composites The temperature dependence of the electrical properties of composites formed by biphasic sodium titanate and poly(<i>o</i>-methoxyaniline) (Na<sub>2</sub>Ti<sub>3</sub>O<sub>7</sub>/Na<sub>2</sub>Ti<sub>6</sub>O<sub>13</sub>/POMA) with different concentrations of POMA (0%, 1%, 10%, 15%, 35% and 50%) in the ceramic matrix was determined from measurements of complex impedance. The structural details were studied by means of X-ray diffraction, confirming the formation of the Na<sub>2</sub>Ti<sub>3</sub>O<sub>7</sub>/Na<sub>2</sub>Ti<sub>6</sub>O<sub>13</sub>/POMA composites. The displacement of the (200) reflection from 2θ = 10.45° to 11.15° in the composites with 10 and 15% of POMA suggested the partial replacement of H<sup>+</sup> for Na<sup>+</sup> in the Na<sub>2</sub>Ti<sub>3</sub>O<sub>7</sub> structure. The thermal properties were investigated by Thermogravimetry and Differential Thermal Analysis. The Thermogravimetry curves of the composites with POMA content of 1, 10 and 15% presented profiles similar to that of pure sodium titanate sample. The composites with 35 and 50% of POMA showed a process at temperatures around 60-70 °C, which was associated with water absorbed by the polymer. The analysis of the complex impedance spectroscopy measurements revealed that the electrical resistivity of the composites in the range from 0 to 35% increased by two orders of magnitude, with different values for each concentration. This positive temperature coefficient of resistivity was less noticeable in the composite with highest POMA mass content (50%). The rapid increase in resistivity caused an increase in the relaxation time calculated from the time domain. The electrical response of the 50% of POMA compound changes in relation to what was observed in the other compounds, which suggests that there is a saturation limit in the increase in resistivity with POMA content. Thermogravimetry ; Materials science ; Electrical resistivity and conductivity ; Composite material ; Composite number ; Titanate ; Ceramic ; Atmospheric temperature range ; Temperature coefficient ; Analytical Chemistry (journal) ; Chemistry ; Thermodynamics ; Organic chemistry Conducting polymers and applications ; Advanced Battery Materials and Technologies ; Dielectric materials and actuators
Authors: Chaima Bouyahya | Rafael Patrício | Ana Paço | Mafalda S. Lima | Ana C. Fonseca | Teresa Rocha‐Santos | Mustapha Majdoub | Armando J. D. Silvestre | Andreia F. Sousa
Source: Polymers (article, 2022-09-15)
Field: Materials Science — Biomaterials

Isosorbide and 2,5-Furandicarboxylic Acid Based (Co)Polyesters: Synthesis, Characterization, and Environmental Degradation Poly(2,5-furandicarboxylate)s incorporating aliphatic moieties represent a promising family of polyesters, typically entirely based on renewable resources and with tailored properties, notably degradability. This study aims to go beyond by developing poly(isosorbide 2,5-furandicarboxylate-<i>co</i>-dodecanedioate) copolyesters derived from isosorbide (Is), 2,5-furandicarboxylic acid (FDCA), and 1,12-dodecanedioic acid (DDA), and studying their degradation under environmental conditions, often overlooked, namely seawater conditions. These novel polyesters have been characterized in-depth using ATR-FTIR, <sup>1</sup>H, and <sup>13</sup>C NMR and XRD spectroscopies and thermal analysis (TGA and DSC). They showed enhanced thermal stability (up to 330 °C), and the glass transition temperature increased with the content of FDCA from ca. 9 to 60 °C. Regarding their (bio)degradation, the enzymatic conditions lead to the highest weight loss compared to simulated seawater conditions, with values matching 27% vs. 3% weight loss after 63 days of incubation, respectively. Copolymerization of biobased FDCA, Is, and DDA represents an optimal approach for shaping the thermal/(bio)degradation behaviors of these novel polyesters. Polyester ; Isosorbide ; Degradation (telecommunications) ; Thermal stability ; Glass transition ; Materials science ; Organic chemistry ; Polymer chemistry ; Chemistry ; Nuclear chemistry ; Polymer biodegradable polymer synthesis and properties ; Catalysis for Biomass Conversion ; Supercapacitor Materials and Fabrication
Authors: Kun‐You Chung | Kathleen N. Halwachs | Pengtao Lu | Kaihong Sun | Hope A. Silva | Adrianne M. Rosales | Zachariah A. Page
Source: Cell Reports Physical Science (article, 2022-12-01)
Field: Materials Science — Materials Chemistry

Rapid hydrogel formation via tandem visible light photouncaging and bioorthogonal ligation The formation of benign polymer scaffolds in water using green-light-reactive photocages is described. These efforts pave an avenue toward the fabrication of synthetic scaffolds that can facilitate the study of cellular events for disease diagnosis and treatment. First, a series of boron dipyrromethene (BODIPY) photocages with nitrogen-containing nucleophiles were examined to determine structure-reactivity relationships, which resulted in a >1,000× increase in uncaging yield. Subsequently, photoinduced hydrogel formation in 90 wt % water was accomplished via biorthogonal carbonyl condensation using hydrophilic polymer scaffolds separately containing BODIPY photocages and ortho-phthalaldehyde (OPA) moieties. Spatiotemporal control is demonstrated with light on/off experiments to modulate gel stiffness and masking to provide <100 μm features. Biocompatability of the method was shown through pre-/post-crosslinking cell viability studies. Short term, these studies are anticipated to guide translation to emergent additive manufacturing technology, which, longer term, will enable the development of 3D cell cultures for tissue engineering applications. BODIPY ; Polymer ; Bioorthogonal chemistry ; Chemistry ; Viability assay ; Nanotechnology ; Combinatorial chemistry ; Photochemistry ; Materials science ; Fluorescence ; Click chemistry ; Organic chemistry ; Cell ; Biochemistry Photochromic and Fluorescence Chemistry ; Nanoplatforms for cancer theranostics ; 3D Printing in Biomedical Research
Authors: Robin Heckershoff | Lukas Eberle | Garrett May | Petra Krämer | Frank Röminger | Matthias Rudolph | A. Stephen K. Hashmi
Source: Advanced Synthesis & Catalysis (article, 2022-09-06)
Field: Chemistry — Organic Chemistry

Gold‐Catalyzed Bidirectional Access to Planar Heptacyclic Benzobispyrido[1,2‐<i>a</i>]indoles and Benzobispyrrolo[1,2‐<i>a</i>]Quinolines for Materials Science Abstract Our recently developed gold‐catalyzed synthesis of indolo[1,2‐ a ]quinolines was successfully expanded towards bidirectional approaches, enabling access to two heptacyclic structural motifs. In the case of benzobispyrido[1,2‐ a ]indoles, previously inaccessible modifications of the only known representative were made possible. In addition, the synthesis of a new class of nitrogen‐containing heptacycles – namely benzobispyrrolo[1,2‐ a ]quinolines – was achieved by applying alkynylated benzodipyrrole derivatives as starting materials. All new compounds alongside with their corresponding precursors were fully characterized and their properties were investigated by X‐ray crystallography, photophysical measurements and computational methods. The study revealed important structure‐effect relationships between the solid‐state structures and the observed photophysical properties, e. g. aggregation‐induced emission and solid‐state fluorescence. magnified image Chemistry ; Catalysis ; Fluorescence ; Solid-state ; Combinatorial chemistry ; Aggregation-induced emission ; Photochemistry ; Organic chemistry ; Physical chemistry Catalytic Alkyne Reactions ; Catalytic C–H Functionalization Methods ; Cyclopropane Reaction Mechanisms