jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ruben Feringa | Harmke S. Siebe | W. J. Niels Klement | Jorn D. Steen | Wesley R. Browne
Source: Materials Advances (article, 2021-10-28)
Field: Materials Science — Materials Chemistry

Single wavelength colour tuning of spiropyran and dithienylethene based photochromic coatings Controlling the transmission of thin films with external stimuli is an important goal in functional optical materials and devices. Tuning is especially challenging where both broad band (neutral density filtering) and spectrally varied (colour) transmission are required. The external control provided by photochemically driven switching, between transmission levels and colours, is functionally simple from a device perspective. The limits due to the spectral ranges of individual photochromic compounds can be overcome by combining several photochromes within one material or device. Here we show that a combination of photochromic molecular switches immobilised in a PMMA polymer matrix enables tuning of colour and transparency. We show that only a single excitation wavelength is required through the use of the primary inner filter effect and the layered construction of the films in which the photochromes nitrospiropyran (NSP), and nitrothiospiropyran (TSP) or 1,2-bis-terthienyl-hexafluorocyclopentene (<b>DTE</b>) are separated spatially. The approach taken circumvents the need to match photochemical quantum yields and thermal reactivity of the component photochromes. The photochemical switching of the films was characterised by UV/vis absorption spectroscopy and shows that switching rates and photostationary states are limited by inner filter effects rather than the intrinsic properties of photochromes, such as photochemical quantum yields and thermal stability. The photochemical behaviour and stability of the photochromes in solution and in the PMMA films were compared and the concentration range over which self-inhibition of photochemical switching occurs was established. The rate of photochemical switching and the difference in transmission between the spiropyran and merocyanine forms in solution enable prediction of the performance in the films and enable rational design of colour tuning ranges and responsivity in thin film filters. Photochromism ; Spiropyran ; Wavelength ; Materials science ; Coating ; Optoelectronics ; Visible spectrum ; Optics ; Transmission (telecommunications) ; Layer (electronics) ; Nanotechnology ; Computer science ; Physics ; Telecommunications Photochromic and Fluorescence Chemistry ; Photoreceptor and optogenetics research ; Polydiacetylene-based materials and applications
Authors: Gizem Cihanoğlu | Özgenç Ebil
Source: Journal of Materials Science (article, 2021-04-12)
Field: Materials Science — Materials Chemistry

Robust fluorinated siloxane copolymers via initiated chemical vapor deposition for corrosion protection Materials science ; Corrosion ; Copolymer ; Tafel equation ; Polymer ; Zinc ; Methacrylate ; Chemical vapor deposition ; Siloxane ; Fluoropolymer ; Chemical engineering ; Dielectric spectroscopy ; Polymer chemistry ; Electrochemistry ; Composite material ; Metallurgy ; Nanotechnology ; Chemistry ; Physical chemistry ; Electrode Corrosion Behavior and Inhibition ; Marine Biology and Environmental Chemistry ; Lubricants and Their Additives
Authors: Jiuxing Li | Yingfu Li
Source: Analytical and Bioanalytical Chemistry (article, 2021-03-18)
Field: Materials Science — Materials Chemistry

One-pot high-yield synthesis of Pd nanocubes for Pd-Ir nanocube-based immunoassay of nucleocapsid protein from SARS-CoV-2 Yield (engineering) ; Horseradish peroxidase ; Immunoassay ; Combinatorial chemistry ; Nanotechnology ; Peroxidase ; Catalysis ; One-pot synthesis ; Materials science ; Palladium ; Chemistry ; Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ; Coronavirus disease 2019 (COVID-19) ; Enzyme ; Organic chemistry ; Metallurgy Advanced Nanomaterials in Catalysis ; Advanced biosensing and bioanalysis techniques ; Electrochemical sensors and biosensors
Authors: Camila Campos-Escamilla | Dritan Siliqi | Luis A. González-Ramírez | Carmen López‐Sánchez | Jose Antonio Gavira | Abel Moreno
Source: International Journal of Molecular Sciences (article, 2021-12-13)
Field: Materials Science — Materials Chemistry

X-ray Characterization of Conformational Changes of Human Apo- and Holo-Transferrin Human serum transferrin (Tf) is a bilobed glycoprotein whose function is to transport iron through receptor-mediated endocytosis. The mechanism for iron release is pH-dependent and involves conformational changes in the protein, thus making it an attractive system for possible biomedical applications. In this contribution, two powerful X-ray techniques, namely Macromolecular X-ray Crystallography (MX) and Small Angle X-ray Scattering (SAXS), were used to study the conformational changes of iron-free (apo) and iron-loaded (holo) transferrin in crystal and solution states, respectively, at three different pH values of physiological relevance. A crystallographic model of glycosylated apo-Tf was obtained at 3.0 Å resolution, which did not resolve further despite many efforts to improve crystal quality. In the solution, apo-Tf remained mostly globular in all the pH conditions tested; however, the co-existence of closed, partially open, and open conformations was observed for holo-Tf, which showed a more elongated and flexible shape overall. Transferrin ; Small-angle X-ray scattering ; Chemistry ; Endocytosis ; Crystallography ; Conformational change ; Macromolecule ; Resolution (logic) ; Function (biology) ; Biophysics ; Biochemistry ; Scattering ; Receptor ; Biology ; Cell biology ; Physics Enzyme Structure and Function ; Iron Metabolism and Disorders ; Porphyrin Metabolism and Disorders
Authors: Hassanein Shaban | Shih-Chun Yen | Mon‐Juan Lee | Wei Lee
Source: Biosensors (article, 2021-03-13)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Signal Amplification in an Optical and Dielectric Biosensor Employing Liquid Crystal-Photopolymer Composite as the Sensing Medium An optical and dielectric biosensor based on a liquid crystal (LC)-photopolymer composite was established in this study for the detection and quantitation of bovine serum albumin (BSA). When the nematic LC E7 was doped with 4-wt.% NOA65, a photo-curable prepolymer, and photopolymerized by UV irradiation at 20 mW/cm<sup>2</sup> for 300 s, the limit of detection determined by image analysis of the LC optical texture and dielectric spectroscopic measurements was 3400 and 88 pg/mL for BSA, respectively, which were lower than those detected with E7 alone (10 μg/mL BSA). The photopolymerized NOA65, but not the prepolymer prior to UV exposure, contributed to the enhanced optical signal, and UV irradiation of pristine E7 in the absence of NOA65 had no effect on the optical texture. The effective tilt angle <i>θ</i>, calculated from the real-part dielectric constant <i>ε</i>', decreased with increasing BSA concentration, providing strong evidence for the correlation of photopolymerized NOA65 to the intensified disruption in the vertically oriented LC molecules to enhance the optical and dielectric signals of BSA. The optical and dielectric anisotropy of LCs and the photo-curable dopant facilitate novel quantitative and signal amplification approaches to potential development of LC-based biosensors. Liquid crystal ; Dielectric ; Materials science ; Dopant ; Photopolymer ; Biosensor ; Prepolymer ; Texture (cosmology) ; Bovine serum albumin ; Irradiation ; Composite number ; Analytical Chemistry (journal) ; Doping ; Polymer ; Optoelectronics ; Polymerization ; Chemistry ; Nanotechnology ; Chromatography ; Composite material Liquid Crystal Research Advancements ; Photonic and Optical Devices ; Advanced Fiber Optic Sensors
Authors: Alessandro Landi | Francesco F. Summa | Guglielmo Monaco
Source: Chemistry (article, 2021-09-02)
Field: Chemistry — Organic Chemistry

Magnetic Aromaticity of Cycloporphyrin Nanorings The ascertainment of magnetic aromaticity is not necessarily straightforward, especially for large and bent systems, such as the cycloporphyrin nanorings recently synthesized by the group of Anderson. Six of these cycloporphyrin nanorings were studied here computationally. Indirect methods, based on nuclear shielding and magnetizabilities, and direct methods, based on standard quantum mechanics, were both used effectively to determine their magnetically induced current strength, which mostly confirmed Anderson’s classification. However, in the case of hexanions, and in particular for cyclohexaporphyrin hexacations, a significant cancellation of delocalized diatropic and paratropic flow occurred, showing that the resultant faint aromatic character was a result of competing aromatic and antiaromatic contributions, as also evidenced by the ipsocentric method. A warning is renewed on the use of isotropic shielding to determine the tropicity of the magnetically induced current. Aromaticity ; Antiaromaticity ; Delocalized electron ; Electromagnetic shielding ; Isotropy ; Bent molecular geometry ; Character (mathematics) ; Current (fluid) ; Quantum ; Physics ; Computational chemistry ; Chemical physics ; Materials science ; Chemistry ; Quantum mechanics ; Mathematics ; Thermodynamics ; Molecule Synthesis and Properties of Aromatic Compounds ; Porphyrin and Phthalocyanine Chemistry ; Advanced Chemical Physics Studies
Authors: Т. М. Полетика | С. Л. Гирсова | А. И. Лотков | Andrej N. Kudryachov | Н. В. Гирсова
Source: Metals (article, 2021-08-10)
Field: Materials Science — Materials Chemistry

Structure and Multistage Martensite Transformation in Nanocrystalline Ti-50.9Ni Alloy An electron microscopic study of the evolution of the size, morphology, and spatial distribution of coherent Ti3Ni4 particles with a change in the aging temperature in a nanocrystalline (NC) Ti-50.9 at % Ni alloy with an inhomogeneous grain–subgrain B2-austenitic nanostructure has been carried out. It was found that with an increase in the aging temperature, along with a change in the size and shape of Ti3Ni4 nanoparticles, their spatial distribution changes from location at dislocations to precipitates at subboundaries. Research has shown that the presence of different types of internal interfaces in the nanostructure contributes to the heterogeneous distribution of coherent Ti3Ni4 nanoparticles in the volume of the B2 matrix, which is associated with the precipitation of particles in the region of low-angle subboundaries and the suppression of the Ti3Ni4 precipitation in nanograins with high-angle boundaries. The difference in the structural-phase state of nanograins and subgrains regions is the main reason for the implementation of the anomalous R-phase transformation effect in the sequence of multistage martensitic transformations B2↔R↔B19′. Nanocrystalline material ; Materials science ; Nanostructure ; Precipitation ; Austenite ; Martensite ; Alloy ; Phase (matter) ; Grain size ; Diffusionless transformation ; Shape-memory alloy ; Metallurgy ; Grain boundary ; Condensed matter physics ; Crystallography ; Microstructure ; Nanotechnology ; Chemistry Shape Memory Alloy Transformations ; Titanium Alloys Microstructure and Properties ; Intermetallics and Advanced Alloy Properties
Authors: Kathleen D. Cusick | Ane Iturbide | Pratima Gautam | Amelia Price | Shawn W. Polson | Madolyn L. MacDonald | Ivan Erill
Source: PLoS ONE (article, 2021-09-28)
Field: Materials Science — Materials Chemistry

Enhanced copper-resistance gene repertoire in Alteromonas macleodii strains isolated from copper-treated marine coatings Copper is prevalent in coastal ecosystems due to its use as an algaecide and as an anti-fouling agent on ship hulls. Alteromonas spp. have previously been shown to be some of the early colonizers of copper-based anti-fouling paint but little is known about the mechanisms they use to overcome this initial copper challenge. The main models of copper resistance include the Escherichia coli chromosome-based Cue and Cus systems; the plasmid-based E. coli Pco system; and the plasmid-based Pseudomonas syringae Cop system. These were all elucidated from strains isolated from copper-rich environments of agricultural and/or enteric origin. In this work, copper resistance assays demonstrated the ability of Alteromonas macleodii strains CUKW and KCC02 to grow at levels lethal to other marine bacterial species. A custom database of Hidden Markov Models was designed based on proteins from the Cue, Cus, and Cop/Pco systems and used to identify potential copper resistance genes in CUKW and KCC02. Comparative genomic analyses with marine bacterial species and bacterial species isolated from copper-rich environments demonstrated that CUKW and KCC02 possess genetic elements of all systems, oftentimes with multiple copies, distributed throughout the chromosome and mega-plasmids. In particular, two copies of copA (the key player in cytoplasmic detoxification), each with its own apparent MerR-like transcriptional regulator, occur on a mega-plasmid, along with multiple copies of Pco homologs. Genes from both systems were induced upon exposure to elevated copper levels (100 μM- 3 mM). Genomic analysis identified one of the merR-copA clusters occurs on a genomic island (GI) within the plasmid, and comparative genomic analysis found that either of the merR-copA clusters, which also includes genes coding for a cupredoxin domain-containing protein and an isoprenylcysteine methyltransferase, occurs on a GI across diverse bacterial species. These genomic findings combined with the ability of CUKW and KCC02 to grow in copper-challenged conditions are couched within the context of the genome flexibility of the Alteromonas genus. Alteromonas ; Plasmid ; Biology ; Escherichia coli ; Genomic island ; Microbiology ; Copper ; Genetics ; Gene ; Pseudomonas syringae ; Bacteria ; Chemistry Corrosion Behavior and Inhibition ; Marine Biology and Environmental Chemistry ; Metal Extraction and Bioleaching
Authors: Cris Kostmann | Thomas Lisec | Mani Teja Bodduluri | Olaf Andersen
Source: Micromachines (article, 2021-09-29)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Automated Filling of Dry Micron-Sized Particles into Micro Mold Pattern within Planar Substrates for the Fabrication of Powder-Based 3D Microstructures Powder-based techniques are gaining increasing interest for the fabrication of microstructures on planar substrates. A typical approach comprises the filling of a mold pattern with micron-sized particles of the desired material, and their fixation there. Commonly powder-loaded pastes or inks are filled into the molds. To meet the smallest dimensions and highest filling factors, the utilization of dry powder as the raw material is more beneficial. However, an appropriate automated technique for filling a micro mold pattern with dry micron-sized particles is missing up to now. This paper presents a corresponding approach based on the superimposition of high- and low-frequency oscillations for particle mobilization. Rubber balls are utilized to achieve dense packing. For verification, micromagnets are created from 5 µm NdFeB powder on 8" Si substrates, using the novel automated mold filling technique, as well as an existing manual one. Subsequent atomic layer deposition is utilized to agglomerate the loose NdFeB particles into rigid microstructures. The magnetic properties and inner structure of the NdFeB micromagnets are investigated. It is shown that the novel automated technique outperforms the manual one in major terms. Materials science ; Fabrication ; Agglomerate ; Microstructure ; Mold ; Neodymium magnet ; Composite material ; Planar ; Particle (ecology) ; LIGA ; Magnet ; Mechanical engineering ; Computer science Magnetic Properties of Alloys ; Metallic Glasses and Amorphous Alloys ; Additive Manufacturing and 3D Printing Technologies
Authors: Jason Hattrick‐Simpers | Brian DeCost | A. Gilad Kusne | Howie Joress | W. Wong‐Ng | Debra L. Kaiser | Andriy Zakutayev | Caleb Phillips | Shijing Sun | Janak Thapa | Heshan Yu | Ichiro Takeuchi | Tonio Buonassisi
Source: Integrating materials and manufacturing innovation (article, 2021-06-01)
Field: Materials Science — Materials Chemistry

An Open Combinatorial Diffraction Dataset Including Consensus Human and Machine Learning Labels with Quantified Uncertainty for Training New Machine Learning Models Machine learning ; Computer science ; Artificial intelligence ; Subject-matter expert ; Test set ; Test data ; Data mining ; Benchmark (surveying) ; Expert system Machine Learning in Materials Science ; Transition Metal Oxide Nanomaterials ; Advanced Memory and Neural Computing
Authors: Abdulelah S. Alshehri | Fengqi You
Source: Frontiers in Chemical Engineering (article, 2021-06-08)
Field: Materials Science — Materials Chemistry

Paradigm Shift: The Promise of Deep Learning in Molecular Systems Engineering and Design The application of deep learning to a diverse array of research problems has accelerated progress across many fields, bringing conventional paradigms to a new intelligent era. Just as the roles of instrumentation in the old chemical revolutions, we reinforce the necessity for integrating deep learning in molecular systems engineering and design as a transformative catalyst towards the next chemical revolution. To meet such research needs, we summarize advances and progress across several key elements of molecular systems: molecular representation, property estimation, representation learning, and synthesis planning. We further spotlight recent advances and promising directions for several deep learning architectures, methods, and optimization platforms. Our perspective is of interest to both computational and experimental researchers as it aims to chart a path forward for cross-disciplinary collaborations on synthesizing knowledge from available chemical data and guiding experimental efforts. Transformative learning ; Deep learning ; Computer science ; Data science ; Artificial intelligence ; Representation (politics) ; Management science ; Systems engineering ; Engineering Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Process Optimization and Integration
Authors: Vikram More | Supriya Kadam | Satish B. Shelke | Pravin Gaikwad | R.H. Kadam | S. T. Alone | K Rady | M Shams | S Nithiyanantham | S Viviliya | S Anadhan | S Mahalakshmi | S Wadgane | S Alone | A Karim | G Vats | S Shirsath | R Kadam | Y Kumar | V Vashistha | D Das | A Birajdar | S Patange | D Mane | A Shitre | M Mane | A Ghasemi | Y Yasukawa | X Liu | A Morisako | N Abu-Elsaad | S Mazen | A Nawara | K Saija | N Vasoya | S Modi | U Meshiya | K Jani | P Raval | K Modi | K Desai | V Shinde | M Hashim | R Borade | K Batoo | Structural | R El-Shater | H El Shimy | S Assar | S Kumar | C Lee | M Ali | M Khan | M Hossain | F Chowdhury | R Rashid | M Hakim | S Hoque | M Uddin | S Choudhari | S Shelke | S Adil | A Kadam | A Imran | M Hadi | E Raslan | S Satpute | S Kadam | P Akhtar | M Akhtar | M Baqir | A Ahmad | M Khallidoon | M Farhan | N Rezlescu | E Rezlescu | C Pasnicu | M Craus | K Desai; R. Mane
Source: Biointerface Research in Applied Chemistry (article, 2021-10-17)
Field: Materials Science — Materials Chemistry

Modified Structural and Magnetic Properties of Ni-Mn-Zn Ferrite Nanoparticles Doped with Ce3+Ions Polycrystalline Ni-Mn-Zn nano-ferrites doped by the fractional amount of Ce3+ ions were fabricated using the sol-gel method. Characterizations of the as-prepared samples were performed by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), vibrating sample magnetometer (VSM), and dielectric measurements. Rietveld refined XRD patterns revealed the single-phase cubic spinel structure of the samples corresponds to the space group Fd-3m. Minor shifting of peak positions towards lower diffraction angles increases lattice parameter from 8.4105 to 8.4193 Å with the addition of Ce3+ ions. , The surface morphology and homogeneity of the samples were investigated by using SEM and EDAX spectra. Grain size obtained from SEM analysis is found in the range 29 nm to 33 nm with negligible agglomeration. Analysis of EDAX spectra confirms the stoichiometric proportion of the constituents. Substitution of Ce3+ ions shows typical ferromagnetic curves with enhanced saturation magnetization and magneton number from 54 to 63 emu/gm and 2.71 to 3.09 B respectively. Dielectric measurements of the entire samples show the typical behavior of spinel ferrite. The results predict that the samples are best suitable for high-frequency region applications. Materials science ; Analytical Chemistry (journal) ; Spinel ; Rietveld refinement ; Crystallite ; Ferrite (magnet) ; Scanning electron microscope ; Dielectric ; Ion ; Lattice constant ; Nanocrystalline material ; Diffraction ; Crystal structure ; Crystallography ; Chemistry ; Nanotechnology ; Metallurgy ; Optics Magnetic Properties and Synthesis of Ferrites ; Electromagnetic wave absorption materials ; Iron oxide chemistry and applications
Authors: Mohammed Mahmood Katun | Rudo K. Sithole | Nosipho Moloto | Cuthbert Nyamupangedengu | Chandima Gomes
Source: Energies (article, 2021-11-29)
Field: Materials Science — Biomaterials

Improving Thermal Stability and Hydrophobicity of Rutile-TiO2 Nanoparticles for Oil-Impregnated Paper Application Thermal stress and moisture absorption can cause a synergetic negative impact on kraft paper. Among various approaches for improving the dielectric properties of kraft paper, nanotechnology has had promising results. However, the hydrophilicity of most metal oxide nanoparticles renders nanomodified kraft paper more vulnerable to thermal stress and moisture, thereby inducing degradation. In nanomodified kraft paper research, the use of TiO2 nanoparticles has yielded the most promising results. The major shortfall, however, is the hydrophilicity of TiO2. This work investigated surface modifications of rutile-TiO2 nanoparticles (NPs) for improved hydrophobicity and thermal stability. Rutile-TiO2 NPs is a nontoxic metal oxide that can withstand high temperature and is stable in chemical reactions. Two cases of surfactants were used—alkyl ketene dimer (AKD) and alkenyl succinic anhydride (ASA). The intention was to increase heat resistance and reduce the surface free energy of the rutile-TiO2 NPs. The impacts of the surface modifiers on the rutile-TiO2 NPs were characterised using FT-IR, muffle furnace, analytical weight balance, and TGA. It was discovered that new functional groups were formed on the modified NPs examined through FT-IR spectra. This indicates new chemical bonds, introduced through the surface modification. The unmodified rutile-TiO2 NPs absorbed moisture, increasing their mass by 3.88%, compared with the modified nanoparticles, which released moisture instead. TGA analysis revealed that AKD- and ASA-modified rutile-TiO2 needed higher temperatures than the unmodified rutile-TiO2 to markedly decompose. AKD, however, gave better performance than ASA in that regard. As an example, those modified with 5% AKD sustained a 45% higher temperature than the pure TiO2 nanoparticles. Furthermore, in both cases of the surfactants, the higher the percent of surfactant content was, the more thermally stable the nanoparticles became. This work demonstrates the possibility of fabricating rutile-TiO2 NPs to give improved hydrophobicity and thermal stability for possible dielectric applications such as in kraft paper for power transformer insulation. Rutile ; Chemical engineering ; Materials science ; Nanoparticle ; Thermal stability ; Moisture ; Titanium dioxide ; Composite material ; Nanotechnology Advanced Cellulose Research Studies ; Electrospun Nanofibers in Biomedical Applications ; Nanocomposite Films for Food Packaging