jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Masayoshi Tanaka | Mirei Hayashi | Lucien Roach | Yuka Kiriki | Tetsuya Kadonosono | Takahiro Nomoto | Nobuhiro Nishiyama | Jonghoon Choi | Kevin Critchley | Stephen D. Evans | Mina Okochi
Source: Acta Biomaterialia (article, 2021-06-15)
Field: Materials Science — Biomaterials

Synthesis of near-infrared absorbing triangular Au nanoplates using biomineralisation peptides Materials science ; Infrared ; Nanotechnology ; Chemical engineering ; Composite material ; Optics ; Engineering Diatoms and Algae Research ; Bone Tissue Engineering Materials ; Supramolecular Self-Assembly in Materials
Authors: Hamidreza Daghigh Shirazi | Yujiao Dong | Jukka Niskanen | Chiara Fedele | Arri Priimägi | Ville Jokinen | Jaana Vapaavuori
Source: ACS Applied Materials & Interfaces (article, 2021-03-23)
Field: Materials Science — Surfaces, Coatings and Films

Multiscale Hierarchical Surface Patterns by Coupling Optical Patterning and Thermal Shrinkage Herein, a simple hierarchical surface patterning method is presented by effectively combining buckling instability and azopolymer-based surface relief grating inscription. In this technique, submicron patterns are achieved using azopolymers, whereas the microscale patterns are fabricated by subsequent thermal shrinkage. The wetting characterization of various topographically patterned surfaces confirms that the method permits tuning of contact angles and choosing between isotropic and anisotropic wetting. Altogether, this method allows efficient fabrication of hierarchical surfaces over several length scales in relatively large areas, overcoming some limitations of fabricating multiscale roughness in lithography and also methods of creating merely random patterns, such as black silicon processing or wet etching of metals. The demonstrated fine-tuning of the surface patterns may be useful in optimizing surface-related material properties, such as wetting and adhesion, producing substrates that are of potential interest in mechanobiology and tissue engineering. Materials science ; Microscale chemistry ; Wetting ; Fabrication ; Isotropy ; Nanotechnology ; Nanoimprint lithography ; Isotropic etching ; Surface roughness ; Photolithography ; Lithography ; Surface finish ; Shrinkage ; Etching (microfabrication) ; Composite material ; Optoelectronics ; Optics ; Layer (electronics) Surface Modification and Superhydrophobicity ; Advanced Materials and Mechanics ; Adhesion, Friction, and Surface Interactions
Authors: Chunnan Wang | Ruomei Shao | Guiqiang Wang | Jingru Zhao | Zhou Sha | Shuqing Sun
Source: Surface and Coatings Technology (article, 2021-02-27)
Field: Materials Science — Materials Chemistry

Controllable wet etching of porous anodic alumina toward highly ordered hierarchical interfaces Materials science ; Porosity ; Etching (microfabrication) ; Anode ; Nanotechnology ; Chemical engineering ; Composite material ; Chemistry ; Layer (electronics) ; Electrode ; Physical chemistry ; Engineering Anodic Oxide Films and Nanostructures ; Smart Materials for Construction ; Semiconductor materials and devices
Authors: Dragan Miscevic | Ju‐Yi Mao | Bradley Mozell | Kajan Srirangan | Daryoush Abedi | Murray Moo‐Young | C. Perry Chou
Source: Applied Microbiology and Biotechnology (article, 2021-01-23)
Field: Materials Science — Biomaterials

Bio-based production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with modulated monomeric fraction in Escherichia coli Escherichia coli ; Metabolic engineering ; Biosynthesis ; Biochemistry ; Operon ; Polyhydroxyalkanoates ; Monomer ; Chemistry ; Biology ; Bacteria ; Enzyme ; Organic chemistry ; Gene biodegradable polymer synthesis and properties ; Microbial Metabolic Engineering and Bioproduction ; Biofuel production and bioconversion
Authors: Jianyu Wei | Peter L. Rodríguez‐Kessler | Jean‐François Halet | Samia Kahlal | Jean‐Yves Saillard | Alvaro Muñoz‐Castro
Source: Inorganic Chemistry (article, 2021-05-25)
Field: Materials Science — Materials Chemistry

On Heteronuclear Isoelectronic Alternatives to [Au<sub>13</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>]<sup>3+</sup>: Electronic and Optical Properties of the 18-Electron Os@[Au<sub>12</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>] Cluster from Relativistic Density Functional Theory Computations The development of well-defined atomically precise heteronuclear nanoclusters passivated by protecting ligands is presently a booming area, owing to the fact that doping well-known homonuclear nanostructures allows fine-tuning of their properties. Here, we explore by means of density functional theory calculations the possibility of doping the central gold atom in the classical [Au<sub>13</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>]<sup>3+</sup>cluster (<b>1</b>) by Os. Although both [Au<sub>13</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>]<sup>3+</sup> and [Os@Au<sub>12</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>] have the same total number of electrons, we show that they are not isoelectronic within the formalism of the superatom model, being respectively an 8- and an 18-electron species. It results that they exhibit similar structures but present significantly different optical behaviors (ultraviolet/visible and circular dichroism). Similar results are obtained for the Ru and Fe relatives. Emission properties indicate some redshift of the T<sub>1</sub>→S<sub>1</sub> decay with respect to [Au<sub>13</sub>(dppe)<sub>5</sub>Cl<sub>2</sub>]<sup>3+</sup>, involving an equatorial distortion of the Au<sub>12</sub>Cl<sub>2</sub> core in the T<sub>1</sub> state, rather than the axial distortion afforded by <b>1</b>. The sizable highest occupied molecular orbital-lowest unoccupied molecular orbital gaps found for the three doped species suggest that further experimental exploration of different stable doped species derived from the ligand-protected Au<sub>12</sub>Cl<sub>2</sub> core should be encouraged. Chemistry ; Heteronuclear molecule ; Superatom ; Homonuclear molecule ; Nanoclusters ; Crystallography ; Magnetic circular dichroism ; Delocalized electron ; Electron ; Density functional theory ; Electronic structure ; Gold cluster ; Atomic physics ; Molecular physics ; Molecule ; Computational chemistry ; Stereochemistry ; Spectral line ; Nuclear magnetic resonance spectroscopy ; Physics Nanocluster Synthesis and Applications ; Advanced Nanomaterials in Catalysis ; Pharmacological Effects and Toxicity Studies
Authors: Rabiu Salihu | M.N.M. Ansari | Saiful Izwan Abd Razak | Nurliyana Ahmad Zawawi | Shafinaz Shahir | Mohd Helmi Sani | Muhammad Hanif Ramlee | Mohammed Ahmad Wsoo | Abdul Halim Mohd Yusof | Nadirul Hasraf Mat Nayan | Ahmad Mohammed Gumel
Source: Polymers (article, 2021-08-31)
Field: Materials Science — Biomaterials

Catalyst-Free Crosslinking Modification of Nata-de-Coco-Based Bacterial Cellulose Nanofibres Using Citric Acid for Biomedical Applications Bacterial cellulose (BC) has gained attention among researchers in materials science and bio-medicine due to its fascinating properties. However, BC's fibre collapse phenomenon (i.e., its inability to reabsorb water after dehydration) is one of the drawbacks that limit its potential. To overcome this, a catalyst-free thermal crosslinking reaction was employed to modify BC using citric acid (CA) without compromising its biocompatibility. FTIR, XRD, SEM/EDX, TGA, and tensile analysis were carried out to evaluate the properties of the modified BC (MBC). The results confirm the fibre crosslinking phenomenon and the improvement of some properties that could be advantageous for various applications. The modified nanofibre displayed an improved crystallinity and thermal stability with increased water absorption/swelling and tensile modulus. The MBC reported here can be used for wound dressings and tissue scaffolding. Bacterial cellulose ; Crystallinity ; Biocompatibility ; Materials science ; Thermal stability ; Citric acid ; Ultimate tensile strength ; Cellulose ; Coco ; Absorption of water ; Catalysis ; Swelling ; Chemical engineering ; Fourier transform infrared spectroscopy ; Thermogravimetric analysis ; Carboxymethyl cellulose ; Composite material ; Nuclear chemistry ; Chemistry ; Organic chemistry ; Metallurgy Advanced Cellulose Research Studies ; Electrospun Nanofibers in Biomedical Applications ; Nanocomposite Films for Food Packaging
Authors: Emese Gál | Csaba L. Nagy
Source: Symmetry (article, 2021-12-02)
Field: Materials Science — Materials Chemistry

Photophysical Properties and Electronic Structure of Symmetrical Curcumin Analogues and Their BF2 Complexes, Including a Phenothiazine Substituted Derivative Symmetrically substituted curcumin analogue compounds possess electron donor moieties at both ends of the conjugated systems; their difluoroboron complexes were synthesized, and their structures were fully characterized. A novel compound with enhanced photophysical properties bearing phenothiazine moieties is reported. The introduction of BF2 into the molecular structures resulted in bathochromic shifts both in the absorption and emission spectra, indicating that the π-conjugation was more extended than the one in the initial compounds. The solvatochromic effects were studied, which in case of the phenothiazinyl-curcumin BF2 complex was the most notable. Theoretical study of the investigated compounds was carried out using DFT and TD-DFT methods to evaluate the ground state geometries and vertical excitation energies. Bathochromic shift ; Solvatochromism ; Phenothiazine ; Conjugated system ; Photochemistry ; Chemistry ; Curcumin ; Fluorescence ; Absorption spectroscopy ; Absorption (acoustics) ; Electronic structure ; Materials science ; Molecule ; Computational chemistry ; Organic chemistry ; Polymer Porphyrin and Phthalocyanine Chemistry ; Photochromic and Fluorescence Chemistry ; Luminescence and Fluorescent Materials
Authors: Nicolò Manfredini | Marco Tomasoni | Mattia Sponchioni | Davide Moscatelli
Source: Polymers (article, 2021-03-26)
Field: Chemistry — Organic Chemistry

Influence of the Polymer Microstructure over the Phase Separation of Thermo-Responsive Nanoparticles Thermo-responsive nanoparticles (NPs), i.e., colloids with a sharp and often reversible phase separation in response to thermal stimuli, are coming to the forefront due to their dynamic behavior, useful in applications ranging from biomedicine to advanced separations and smart optics. What is guiding the macroscopic behavior of these systems above their critical temperature is mainly the microstructure of the polymer chains of which these NPs are comprised. Therefore, a comprehensive understanding of the influence of the polymer properties over the thermal response is highly required to reproducibly target a specific behavior. In this study, we synthesized thermo-responsive NPs with different size, polymeric microstructure and hydrophilic-lipophilic balance (HLB) and investigated the role of these properties over their phase separation. We first synthesized four different thermo-responsive oligomers via Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization of poly(ethylene glycol)methyl ether methacrylate. Then, exploiting the RAFT living character, we chain-extended these oligomers with butyl methacrylate obtaining a library of NPs. Finally, we investigated the NP thermo-responsive behavior, their physical state above the cloud point (Tcp) as well as their reversibility once the stimulus is removed. We concluded that the solid content plays a minor role compared to the relative length of the two blocks forming the polymer chains. In particular, the longer the stabilizer, the more favored the formation of a gel. At the same time, the reversibility is mainly achieved at high HLB, independently from the absolute lengths of the block copolymers. Raft ; Materials science ; Polymer ; Chain transfer ; Chemical engineering ; Microstructure ; Lower critical solution temperature ; Methacrylate ; Nanoparticle ; Copolymer ; Polymerization ; Ethylene glycol ; Polymer chemistry ; Phase (matter) ; Nanotechnology ; Radical polymerization ; Chemistry ; Organic chemistry ; Composite material Advanced Polymer Synthesis and Characterization ; Innovative Microfluidic and Catalytic Techniques Innovation ; Nanoparticle-Based Drug Delivery
Authors: Nicholas M. Hein | Gregory A. MacNeil | Tim Storr
Source: Inorganic Chemistry (article, 2021-11-01)
Field: Materials Science — Materials Chemistry

Elaboration on the Electronics of Salen Manganese Nitrides: Investigations into Alkoxy-Substituted Ligand Scaffolds The ligand electronics of salen manganese nitride complexes directly influence the locus of oxidation and, thus, the reactivity of the resulting oxidized species. This work investigates the influence of <i>tert</i>-butoxy, isopropoxy, and methoxy substituents on the electronics of salen manganese nitride species and includes the first documentation of the para Hammett value for the <i>tert</i>-butoxy substituent (σ<sub>para</sub> = -0.13 ± 0.03). Each alkoxy-substituted complex undergoes metal-based oxidation to form manganese(VI), and the kinetics of bimolecular homocoupling to form N<sub>2</sub> were assessed by cyclic voltammetry. Bis-oxidation of the manganese complexes was investigated at low temperature using cyclic voltammery and UV-vis-near-IR spectroscopy, and in combination with theoretical calculations, plausible electronic structures of the dications are provided. Chemistry ; Manganese ; Alkoxy group ; Cyclic voltammetry ; Substituent ; Ligand (biochemistry) ; Metal ; Photochemistry ; Reactivity (psychology) ; Nitride ; Inorganic chemistry ; Electrochemistry ; Medicinal chemistry ; Organic chemistry ; Electrode ; Physical chemistry Porphyrin and Phthalocyanine Chemistry ; Oxidative Organic Chemistry Reactions ; Metal-Catalyzed Oxygenation Mechanisms
Authors: Álvaro Martínez‐Camarena | Matteo Savastano | Salvador Blasco | Estefanía Delgado‐Pinar | Claudia Giorgi | Antonio Bianchi | Enrique García‐España | Carla Bazzicalupi
Source: Inorganic Chemistry (article, 2021-12-22)
Field: Chemistry — Organic Chemistry

Assembly of Polyiodide Networks with Cu(II) Complexes of Pyridinol-Based Tetraaza Macrocycles Polyiodide networks are currently of great practical interest for the preparation of new electronic materials. The participation of metals in the formation of these networks is believed to improve their mechanical performance and thermal stability. Here we report the results on the construction of polyiodide networks obtained using Cu(II) complexes of a series of pyridinol-based tetraazacyclophanes as countercations. The assembly of these crystalline polyiodides takes place from aqueous solutions on the basis of similar structural elements, the [CuL]<sup>2+</sup> and [Cu(H<sub>-1</sub>L)]<sup>+</sup> (L = <b>L2</b>, <b>L2-Me</b>, <b>L2-Me</b><sub><b>3</b></sub>) complex cations, so that the peculiarities induced by the increase of N-methylation of ligands, the structural variable of ligands, can be highlighted. First, solution equilibria involving ligands and complexes were analyzed (potentiometry, NMR, UV-vis, ITC). Then, the appropriate conditions could be selected to prepare polyiodides based on the above complex cations. Single-crystal XRD analysis showed that the coordination of pyridinol units to two metal ions is a prime feature of these ligands, leading to polymeric coordination chains of general formula {[Cu(H<sub>-1</sub>L)]}<sub><i>n</i></sub><sup><i>n</i>+</sup> (L = <b>L2-Me</b>, <b>L2-Me</b><sub><b>3</b></sub>). In the presence of the I<sup>-</sup>/I<sub>2</sub> couple, the polymerization tendency stops with the formation of [(CuL)(CuH<sub>-1</sub>L)]<sup>3+</sup> (L = <b>L2-Me</b>, <b>L2-Me</b><sub><b>3</b></sub>) dimers which are surrounded by polyiodide networks. Moreover, coordination of the pyridinol group to two metal ions transforms the surface charge of the ring from negative to markedly positive, generating a suitable environment for the assembly of polyiodide anions, while N-methylation shifts the directional control of the assembly from H-bonds to I···I interactions. In fact, an extended concatenation of iodine atoms occurs around the complex dimeric cations, the supramolecular I···I interactions become shorter and shorter, fading into stronger forces dominated by the orbital overlap, which is promising for effective electronic materials. Chemistry ; Metal ; Crystallography ; Polymerization ; Aqueous solution ; Crystal structure ; Stereochemistry ; Physical chemistry ; Organic chemistry ; Polymer Supramolecular Chemistry and Complexes ; Lanthanide and Transition Metal Complexes ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Nathan D. Jacobson | Jude O. Iroh
Source: International Journal of Polymer Science (article, 2021-06-29)
Field: Materials Science — Polymers and Plastics

Shape Memory Corrosion-Resistant Polymeric Materials Shape memory alloys, materials capable of being deformed and maintaining the deformation and additionally capable of returning to the initial position, are valued for a range of applications from actuators to flexible microdevices. Maintaining the properties that make them useful, their ability to deform and reform, requires that shape memory alloys must be protected against corrosion, in which the integration of shape memory polymers can act as a means of protection. Thus, this review is to highlight the utility of self-healing shape memory polymers as a means of corrosion inhibition. Therefore, this review discusses the benefits of utilizing self-healing shape memory polymers for the protection of shape memory, several types of self-healing polymers that could be used, means of improving or tailoring the polymers towards specific usages, and future prospects in designing a shape memory polymer for use in corrosion inhibition. Shape-memory alloy ; Shape-memory polymer ; Materials science ; Corrosion ; Polymer ; Actuator ; Deformation (meteorology) ; Nanotechnology ; Composite material ; Computer science ; Artificial intelligence Polymer composites and self-healing ; Marine Sponges and Natural Products ; Synthetic Organic Chemistry Methods
Authors: Jared S. Cobb | Alexandra Engel | Maria Seale | Amol V. Janorkar
Source: Scientific Reports (article, 2021-03-18)
Field: Materials Science — Biomaterials

Machine learning to determine optimal conditions for controlling the size of elastin-based particles This paper evaluates the aggregation behavior of a potential drug and gene delivery system that combines branched polyethyleneimine (PEI), a positively-charged polyelectrolyte, and elastin-like polypeptide (ELP), a recombinant polymer that exhibits lower critical solution temperature (LCST). The LCST behavior of ELP has been extensively studied, but there are no quantitative ways to control the size of aggregates formed after the phase transition. The aggregate size cannot be maintained when the temperature is lowered below the LCST, unless the system exhibits hysteresis and forms irreversible aggregates. This study shows that conjugation of ELP with PEI preserves the aggregation behavior that occurs above the LCST and achieves precise aggregate radii when the solution conditions of pH (3, 7, 10), polymer concentration (0.1, 0.15, 0.3 mg/mL), and salt concentration (none, 0.2, 1 M) are carefully controlled. K-means cluster analyses showed that salt concentration was the most critical factor controlling the hydrodynamic radius and LCST. Conjugating ELP to PEI allowed crosslinking the aggregates and achieved stable particles that maintained their size below LCST, even after removal of the harsh (high salt or pH) conditions used to create them. Taken together, the ability to control aggregate sizes and use of crosslinking to maintain stability holds excellent potential for use in biological delivery systems. Elastin ; Computer science ; Biology ; Genetics Nanoparticle-Based Drug Delivery ; Connective tissue disorders research ; Characterization and Applications of Magnetic Nanoparticles
Authors: Ruhollah Khajavian | Vida Jodaian | Fatemeh Taghipour | Joel T. Mague | Masoud Mirzaei
Source: Molecules (review, 2021-10-02)
Field: Materials Science — Materials Chemistry

Roles of Organic Fragments in Redirecting Crystal/Molecular Structures of Inorganic–Organic Hybrids Based on Lacunary Keggin-Type Polyoxometalates Lacunary polyoxometalates (LPOMs) are key precursors for the synthesis of functional POMs. To date, reviews dedicated to behavioral studies of LPOMs often comprise the role of metal ions, including transition metal (TM) and rare earth (RE) ions, in extending and stability of high-nuclearity clusters. In contrast, the role of organic ligands in the structures and properties of lacunary-based hybrids has remained less explored. In this review, we focus on the role of organic fragments in the self-assembling process of POM-based architectures and discuss relationships between the nature and structure of organic ligand and properties such as the topology of hybrid inorganic-organic material in RE and TM-RE heterometallic derivatives of lacunary Keggin-type POMs. The effects of organic fragment in mixed ligand hybrids are also briefly reviewed. Lacunary function ; Ligand (biochemistry) ; Polyoxometalate ; Lanthanide ; Chemistry ; Crystallography ; Metal ; Ion ; Materials science ; Mathematics ; Organic chemistry ; Receptor ; Catalysis ; Pure mathematics Polyoxometalates: Synthesis and Applications ; Vanadium and Halogenation Chemistry ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Chun‐Chien Chiu | Yao‐Wen Chang | Yu‐Cheng Shao | Yuchen Liu | Jenn-Min Lee | Shih‐Wen Huang | Wanli Yang | Jinghua Guo | Frank M. F. de Groot | Jan‐Chi Yang | Yi‐De Chuang
Source: Scientific Reports (article, 2021-03-04)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Spectroscopic characterization of electronic structures of ultra-thin single crystal La0.7Sr0.3MnO3 We have successfully fabricated high quality single crystalline La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> (LSMO) film in the freestanding form that can be transferred onto silicon wafer and copper mesh support. Using soft x-ray absorption (XAS) and resonant inelastic x-ray scattering (RIXS) spectroscopy in transmission and reflection geometries, we demonstrate that the x-ray emission from Mn 3s-2p core-to-core transition (3sPFY) seen in the RIXS maps can represent the bulk-like absorption signal with minimal self-absorption effect around the Mn L<sub>3</sub>-edge. Similar measurements were also performed on a reference LSMO film grown on the SrTiO<sub>3</sub> substrate and the agreement between measurements substantiates the claim that the bulk electronic structures can be preserved even after the freestanding treatment process. The 3sPFY spectrum obtained from analyzing the RIXS maps offers a powerful way to probe the bulk electronic structures in thin films and heterostructures when recording the XAS spectra in the transmission mode is not available. X-ray absorption spectroscopy ; Heterojunction ; Materials science ; Absorption spectroscopy ; Thin film ; Scattering ; Substrate (aquarium) ; Wafer ; Electronic structure ; Spectroscopy ; Absorption (acoustics) ; Single crystal ; Optoelectronics ; Condensed matter physics ; Optics ; Crystallography ; Nanotechnology ; Chemistry ; Physics Magnetic and transport properties of perovskites and related materials ; Advanced Condensed Matter Physics ; High-pressure geophysics and materials