jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Márkó Grabarics | Maike Lettow | Ansgar T. Kirk | Gert von Helden | Tim Causon | Kevin Pagel
Source: Journal of Separation Science (article, 2021-05-04)
Field: Chemistry — Spectroscopy

Plate‐height model of ion mobility‐mass spectrometry: Part 2—Peak‐to‐peak resolution and peak capacity In a previous work, we explored zone broadening and the achievable plate numbers in linear drift tube ion mobility-mass spectrometry through developing a plate-height model [1]. On the basis of these findings, the present theoretical study extends the model by exploring peak-to-peak resolution and peak capacity in ion mobility separations. The first part provides a critical overview of chromatography-influenced resolution equations, including refinement of existing formulae. Furthermore, we present exact resolution equations for drift tube ion mobility spectrometry based on first principles. Upon implementing simple modifications, these exact formulae could be readily extended to traveling wave ion mobility separations and to cases when ion mobility spectrometry is coupled to mass spectrometry. The second part focuses on peak capacity. The well-known assumptions of constant plate number and constant peak width form the basis of existing approximate solutions. To overcome their limitations, an exact peak capacity equation is derived for drift tube ion mobility spectrometry. This exact solution is rooted in a suitable physical model of peak broadening, accounting for the finite injection pulse and subsequent diffusional spreading. By borrowing concepts from the theoretical toolbox of chromatography, we believe that the present study will help in integrating ion mobility spectrometry into the unified language of separation science. Ion-mobility spectrometry ; Mass spectrometry ; Ion ; Resolution (logic) ; Drift tube ; Chemistry ; Constant (computer programming) ; Basis (linear algebra) ; Analytical Chemistry (journal) ; Computational physics ; Chromatography ; Physics ; Mathematics ; Geometry ; Computer science Mass Spectrometry Techniques and Applications ; Analytical Chemistry and Chromatography ; Metabolomics and Mass Spectrometry Studies
Authors: Ke Wang | Mobin Salasi | Sam Bakhtiari | Mariano Iannuzzi
Source: Journal of The Electrochemical Society (article, 2021-06-01)
Field: Materials Science — Metals and Alloys

On the Critical Factors for Estimating the Pit Stability Product under a Salt Film The pit stability product of 316L stainless steel (SS) under a salt film was examined by experimental techniques, analytical methods, and numerical modeling. Both analytical and numerical results suggested that electromigration had a measurable contribution to the dissolution current during stable pit growth under a salt film, preventing the use of the 1D Fick’s law of diffusion to obtain the pit stability product under such conditions. Moreover, the numerical results indicated that migration contributed to almost ⅔ of the mass transport limiting current. Although the diffusion coefficient of metal cations decreased with an increasing concentration inside the pit, it could be replaced by a constant diffusion coefficient, defined as an equivalent diffusion coefficient. When the complexation reaction was cconsidered, the modeling results agreed with the experimental data, indicating that a 4.2 M FeCl 2 could be used as a simplified pit-like electrolyte to estimate the pit stability product under a salt film for 316L SS. Electromigration ; Diffusion ; Limiting current ; Dissolution ; Salt (chemistry) ; Electrolyte ; Limiting ; Thermodynamics ; Materials science ; Analytical Chemistry (journal) ; Stability (learning theory) ; Metal ; Chemistry ; Effective diffusion coefficient ; Metallurgy ; Composite material ; Electrochemistry ; Chromatography ; Electrode ; Physics ; Physical chemistry Hydrogen embrittlement and corrosion behaviors in metals ; Corrosion Behavior and Inhibition ; Concrete Corrosion and Durability
Authors: B. Rabindran Jermy | Dana Almohazey | Widyan Alamoudi | R M Palanivel | Nora AlSudairi | Hatim Dafalla | Ali Awad Almofleh | Tahani M. Alfareed | Vijaya Ravinayagam
Source: Cancer Nanotechnology (article, 2021-11-27)
Field: Materials Science — Biomaterials

Synergistic action of curcumin and cisplatin on spinel ferrite/hierarchical MCM-41 nanocomposite against MCF-7, HeLa and HCT 116 cancer cell line Abstract Background Platinum-based drugs are widely used in cancer therapy, but are known for toxic side effects and resistance. Combinational drug delivery represents an effective chemotherapeutic strategy, but often leads to an increased toxicity. Aim of this study is to test the co-delivery of cisplatin with natural antioxidants on hierarchial porous large surface area hexagonal nanocarriers for synergistic action. Results A series of structured mesoporous materials were impregnated with magnetic spinel ferrite (30% CuFe 2 O 4 ) and then coated with curcumin (25% wt/wt). Mesosilicalite and MCM-41 with high curcumin release abilities were functionalized with cisplatin (5% wt/wt) for synergistic effect of combinational drugs. The cytotoxic efficiency of our nanocomposites was tested on cell viability of MCF7 (human breast cancer), human cervical cancer (HeLa), colorectal cancer (HCT116), and HFF (human foreskin fibroblasts) cell lines using the MTT cell viability assay. At a concentration of 0.1 mg/ml, CuFe 2 O 4 /mesosilicalite/curcumin/cisplatin resulted in 89.53% reduction in viability in MCF7, 94.03% in HeLa, 64% in HCT116 and 87% in HFF; whereas, CuFe 2 O 4 /MCM-41/curcumin/cisplatin resulted in 76% reduction in viability in MCF7, 64.46% in HeLa, 64% in HCT116 and 24% in HFF. The EC 50 for CuFe 2 O 4 /mesosilicalite/curcumin/cisplatin was 81.23 µg/ml in MCF7, 47.55 µg/ml in HeLa, 48.96 µg/ml in HCT116 and 76.83 µg/ml in HFF. The EC 50 for CuFe 2 O 4 /MCM-41/curcumin/cisplatin was 72.51 µg/ml in MCF7, 58.6 µg/ml in HeLa, 62.58 µg/ml in HCT116 and 154.2 µg/ml in HFF. Furthermore, cells treated with both nanocomposites had a high number of cleaved Caspase 3-positive cells suggesting that the reduction in cell viability was triggered by activating the apoptotic signaling pathway. Conclusion Our results show that CuFe 2 O 4 /MCM-41/curcumin/cisplatin is a better candidate for combinational drug therapy due to its lowest EC 50 value and the wider difference in EC 50 (a fold change) between cancerous and non-cancerous cell line. HeLa ; Curcumin ; Cisplatin ; Viability assay ; MTT assay ; Chemistry ; Pharmacology ; Nuclear chemistry ; Cancer research ; Cancer cell ; Nanocarriers ; Materials science ; Drug delivery ; Cancer ; Cell ; Medicine ; Nanotechnology ; Biochemistry ; Chemotherapy ; Internal medicine Nanoparticle-Based Drug Delivery ; Graphene and Nanomaterials Applications ; Curcumin's Biomedical Applications
Authors: Wenjin Chen | Weiqiang Jia | Cuiying Wu | Lihua Chen | Kai Sun | Ji Wang | Boyun Ding | Ning Liu | Ruxiang Xu
Source: Frontiers in Oncology (article, 2021-06-18)
Field: Chemistry — Spectroscopy

The Neurogenic Compound P7C3 Regulates the Aerobic Glycolysis by Targeting Phosphoglycerate Kinase 1 in Glioma This study revealed that P7C3 suppresses glioma by regulating aerobic glycolysis <i>via</i> directly targeting PGK1. Furthermore, we identified the P7C3 target proteins for the first time which is expected to provide scientific clues for future studies. Phosphoglycerate kinase ; Glycolysis ; Biology ; Chemistry ; Glioma ; Blot ; Biochemistry ; Cell biology ; Molecular biology ; Cancer research ; Metabolism Advanced Proteomics Techniques and Applications ; RNA Research and Splicing ; Glioma Diagnosis and Treatment
Authors: Michael Mauksch | Svetlana B. Tsogoeva
Source: Chemistry - A European Journal (article, 2021-08-10)
Field: Chemistry — Organic Chemistry

Disclosure of Ground‐State Zimmerman‐Möbius Aromaticity in the Radical Anion of [6]Helicene and Evidence for 4π Periodic Aromatic Ring Currents in a Molecular “Metallic” Möbius Strip In 1966, Zimmerman proposed a type of Möbius aromaticity that involves through-space electron delocalization; it has since been widely applied to explain reactivity in pericyclic reactions, but is considered to be limited to transition-state structures. Although the easily accessible hexahelicene radical anion has been known for more than half a century, it was overlooked that it exhibits a ground-state minimum and robust Zimmerman-Möbius aromaticity in its central noose-like opening, becoming, hence, the oldest existing Möbius aromatic system and with smallest Möbius cycle known. Despite its overall aromatic stabilization energy of 13.6 kcal mol<sup>-1</sup> (at B3LYP/6-311+G**), the radical also features a strong, globally induced paramagnetic ring current along its outer edge. Exclusive global paramagnetic currents can also be found in other fully delocalized radical anions of 4N+2 π-electron aromatic polycyclic benzenoid hydrocarbons (PAH), thus questioning the established magnetic criterion of antiaromaticity. As an example of a PAH with nontrivial topology, we studied a novel Möbius[16]cyclacene that has a non-orientable surface manifold and a stable closed-shell singlet ground state at several density functional theory levels. Its metallic monoanion radical (0.0095 eV band gap at HSE06/6-31G* level) is also wave-function stable and displays an unusual 4π-periodic, magnetically induced ring current (reminiscent of the transformation behaviour of spinors under spatial rotation), thus indicating the existence of a new, Hückel-rule-evading type of aromaticity. Helicene ; Aromaticity ; Ring (chemistry) ; Metal ; Ground state ; Chemistry ; Crystallography ; Stereochemistry ; Molecule ; Physics ; Organic chemistry ; Atomic physics Synthesis and Properties of Aromatic Compounds ; Fullerene Chemistry and Applications ; Graph theory and applications
Authors: Javier Ramos‐Soriano | Alfonso Pérez‐Sánchez | Sergio Ramírez‐Barroso | Beatriz M. Illescas | Khalid Azmani | Antonio Rodríguez‐Fortea | Josep M. Poblet | Cormac Hally | Santi Nonell | David García‐Fresnadillo | Javier Rojo | Nazario Martı́n
Source: Angewandte Chemie International Edition (article, 2021-05-13)
Field: Chemistry — Organic Chemistry

An Ultra‐Long‐Lived Triplet Excited State in Water at Room Temperature: Insights on the Molecular Design of Tridecafullerenes Abstract Suitably engineered molecular systems exhibiting triplet excited states with very long lifetimes are important for high‐end applications in nonlinear optics, photocatalysis, or biomedicine. We report the finding of an ultra‐long‐lived triplet state with a mean lifetime of 93 ms in an aqueous phase at room temperature, measured for a globular tridecafullerene with a highly compact glycodendrimeric structure. A series of three tridecafullerenes bearing different glycodendrons and spacers to the C 60 units have been synthesized and characterized. UV/Vis spectra and DLS experiments confirm their aggregation in water. Steady‐state and time‐resolved fluorescence experiments suggest a different degree of inner solvation of the multifullerenes depending on their molecular design. Efficient quenching of the triplet states by O 2 but not by waterborne azide anions has been observed. Molecular modelling reveals dissimilar access of the aqueous phase to the internal structure of the tridecafullerenes, differently shielded by the glycodendrimeric shell. Excited state ; Solvation ; Quenching (fluorescence) ; Triplet state ; Aqueous solution ; Chemical physics ; Photochemistry ; Chemistry ; Materials science ; Fluorescence ; Molecule ; Physical chemistry ; Atomic physics ; Optics ; Physics ; Organic chemistry Fullerene Chemistry and Applications ; Synthesis and Properties of Aromatic Compounds ; Carbon Nanotubes in Composites
Authors: F. Calvo | Aude Simon | P. Parneix | Cyril Falvo | Clément Dubosq
Source: The Journal of Physical Chemistry A (article, 2021-06-17)
Field: Materials Science — Materials Chemistry

Infrared Spectroscopy of Chemically Diverse Carbon Clusters: A Data-Driven Approach Carbon clusters exhibit a broad diversity of topologies and shapes, encompassing fullerene-like cages, graphene-like flakes, and more disordered pretzel-like and branched structures. Here, we examine computationally their infrared spectra in relation with these structures from a statistical perspective. Individual spectra for broad samples of isomers were determined by means of the self-consistent charge density functional-based tight-binding method, and an interpolation scheme is designed to reproduce the spectral features by regression on a much smaller subset of the sample. This interpolation proceeds by encoding the structures using appropriate descriptors and selecting them through principal component analysis, Gaussian regression or inverse distance weighting providing the nonlinear weighting functions. Metric learning is employed to reduce the global error on a preselected testing set. The interpolated spectra satisfactorily reproduce the specific spectral features and their dependence on the size and shape, enabling quantitative prediction away from the testing set. Finally, the classification of structures within the four proposed families is critically discussed through a statistical analysis of the sample based on iterative label spreading. Infrared spectroscopy ; Spectroscopy ; Infrared ; Carbon fibers ; Materials science ; Chemistry ; Nanotechnology ; Physics ; Organic chemistry ; Optics Machine Learning in Materials Science ; X-ray Diffraction in Crystallography ; Boron and Carbon Nanomaterials Research
Authors: Xintong Zhao | Jane Greenberg | Scott McClellan | Yong‐Jie Hu | Steven A. Lopez | Semion K. Saikin | Xiaohua Hu | Yuan An
Source: 2021 IEEE International Conference on Big Data (Big Data) (article, 2021-12-15)
Field: Materials Science — Materials Chemistry

Knowledge Graph-Empowered Materials Discovery In this position paper, we describe research on knowledge graph-empowered materials science prediction and discovery. The research consists of several key components including ontology mapping, materials data annotation, and information extraction from unstructured scholarly articles. We argue that although big data generated by simulations and experiments have motivated and accelerated the data-driven science, the distribution and heterogeneity of materials science-related big data hinders major advancements in the field. Knowledge graphs, as semantic hubs, integrate disparate data and provide a feasible solution to addressing this challenge. We design a knowledge-graph based approach for data discovery, extraction, and integration in materials science. Knowledge graph ; Computer science ; Data science ; Knowledge extraction ; Big data ; Ontology ; Graph ; Field (mathematics) ; Annotation ; Information retrieval ; Key (lock) ; Data mining ; Theoretical computer science ; Artificial intelligence Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Advanced Graph Neural Networks
Authors: Н. Н. Орлова | А. V. Тimonina | N. N. Kolesnikov | E. V. Deviatov
Source: Europhysics Letters (EPL) (article, 2021-08-01)
Field: Materials Science — Materials Chemistry

Switching ferroelectricity in SnSe across phase transition We experimentally investigate transport properties of a hybrid structure, which consists of a thin single crystal SnSe flake on a top of 5~$\mu$m spaced Au leads. The structure initially is in highly-conductive state, while it can be switched to low-conductive one at high currents due to the Joule heating of the sample, which should be identified as $\alpha$-$Pnma$ -- $\beta$-$Cmcm$ diffusionless martensitic phase transition in SnSe. For highly-conductive state, there is significant hysteresis in $dI/dV(V)$ curves at low biases, so the sample conductance depends on the sign of the applied bias change. This hysteretic behavior reflects slow relaxation due to additional polarization current in the ferroelectric SnSe phase, which we confirm by direct measurement of time-dependent relaxation curves. In contrast, we observe no noticeable relaxation or low-bias hysteresis for the quenched $\beta$-$Cmcm$ low-conductive phase. Thus, ferroelectric behavior can be switched on or off in transport through hybrid SnSe structure by controllable $\alpha$-$Pnma$ -- $\beta$-$Cmcm$ phase transition. This result can also be important for nonvolatile memory development, e.g. phase change memory for neuromorphic computations or other applications in artificial intelligence and modern electronics. Ferroelectricity ; Condensed matter physics ; Materials science ; Hysteresis ; Electrical conductor ; Phase transition ; Phase (matter) ; Conductance ; Relaxation (psychology) ; Joule heating ; Nanotechnology ; Optoelectronics ; Physics ; Composite material 2D Materials and Applications ; Perovskite Materials and Applications ; Advanced Thermoelectric Materials and Devices
Authors: Pei Dai | Ziyang Zhang | Xianfei Hou | Lei Ouyang | Li Zhu
Source: Talanta (article, 2021-06-25)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Rapid SERS inspection of carcinogenic aromatic amines in textiles by using liquid interfacial assembled Au array Chemistry ; Reproducibility ; Benzidine ; Textile ; Reagent ; Chromatography ; Organic chemistry ; Materials science Gold and Silver Nanoparticles Synthesis and Applications ; Spectroscopy Techniques in Biomedical and Chemical Research ; Biosensors and Analytical Detection
Authors: Yu Chen | Christopher J. Bartel | Maxim Avdeev | Yaqian Zhang | Jue Liu | Peichen Zhong | Guobo Zeng | Zijian Cai | Haegyeom Kim | Huiwen Ji | Gerbrand Ceder
Source: Chemistry of Materials (article, 2021-12-23)
Field: Materials Science — Materials Chemistry

Solid-State Calcium-Ion Diffusion in Ca<sub>1.5</sub>Ba<sub>0.5</sub>Si<sub>5</sub>O<sub>3</sub>N<sub>6</sub> Rechargeable batteries based on multivalent working ions are promising candidates for next-generation high-energy-density batteries. Development of these technologies, however, is largely limited by the low diffusion rate of multivalent ions in solid-state materials, thereby necessitating a better understanding of the design principles that control multivalent-ion mobility. Here, we report Ca1.5Ba0.5Si5O3N6 as a potential calcium solid-state conductor and investigate its Ca migration mechanism by means of ab initio computations and neutron diffraction. This compound contains partially occupied Ca sites in close proximity to each other, providing a unique mechanism for Ca migration. Nuclear density maps obtained with the maximum entropy method from neutron powder diffraction data provide strong evidence for low-energy percolating one-dimensional pathways for Ca-ion migration. Ab initio molecular dynamics simulations further support a low Ca-ion migration barrier of ∼400 meV when Ca vacancies are present and reveal a unique “vacancy-adjacent” concerted ion migration mechanism. This work provides a new understanding of solid-state Ca-ion diffusion and insights into the future design of novel cation configurations that utilize the interactions between mobile ions to enable fast multivalent-ion conduction in solid-state materials. Ion ; Calcium ; Diffusion ; Materials science ; Solid-state ; Crystallography ; Analytical Chemistry (journal) ; Mineralogy ; Chemistry ; Physical chemistry ; Thermodynamics ; Physics ; Metallurgy Ferroelectric and Piezoelectric Materials ; Inorganic Chemistry and Materials ; Nuclear materials and radiation effects
Authors: Wendimagegn Tagesse
Source: Oriental Journal Of Chemistry (article, 2021-04-30)
Field: Materials Science — Materials Chemistry

Adsorptive Removal of Chromium (VI) Using Silver Nanoparticles Synthesized Via Green Approach with the Extract of Moringastenopetala In the current study, the potential sorption of Cr (VI) ions through a zero-valent silver nanoparticle synthesized by a green approach has been studied. The objective of this research was to remove Cr (VI) from aqueous solution using zero-valent silver nanoparticles synthesized from Moringa stenopetala leaves extract. The synthesized silver nanoparticles were characterized using X-ray diffractometer and UV-visible spectrophotometer. The grain size of nanoparticles was found to be 19.5 nm confirming the crystalline structure of the mesosphere and showed the maximum absorption at 419 nm. In order to determine parameters that influence the adsorption mechanism, batch adsorption experiments have been conducted. Results obtained for removal of Cr (VI) ions showed that efficiency of removal improved as adsorbent dosage increased until the equilibrium point reached at 50 minutes. However, as the pH of the solution increased from 1 to 8, and as the Preliminary concentration of Cr increased, removal efficiency decreased. Adsorption isotherms were investigated by applying the models of Langmuir and Freundlich. The Freundlich isotherm can better explain the removal of Cr (VI) ions, offering correlation coefficient values greater than the Langmuir isotherm model. Adsorption kinetics regression results studied by the pseudo-first and second-order models moreover proved that a pseudo-first-order was further accurately represented by the adsorption kinetics. In order to alleviate wastewater problems, the implementation of this approach is able to cost-effective, eco-friendly and publicly viable. To improve its removal effectiveness and compare it with other adsorbents, additional study on surface modification of this adsorbent is required. Adsorption ; Freundlich equation ; Chemistry ; Sorption ; Aqueous solution ; Langmuir ; Silver nanoparticle ; Chromium ; Langmuir adsorption model ; Nuclear chemistry ; Zerovalent iron ; Nanoparticle ; Inorganic chemistry ; Chemical engineering ; Materials science ; Nanotechnology ; Organic chemistry Nanoparticles: synthesis and applications
Authors: Kristopher Brown | Yasheng Maimaiti | Kai Trepte | Thomas Bligaard | Johannes Voss
Source: Journal of Computational Chemistry (article, 2021-08-18)
Field: Materials Science — Materials Chemistry

<scp>MCML</scp>: Combining physical constraints with experimental data for a multi‐purpose meta‐generalized gradient approximation The predictive power of density functional theory for materials properties can be improved without increasing the overall computational complexity by extending the generalized gradient approximation (GGA) for electronic exchange and correlation to density functionals depending on the electronic kinetic energy density in addition to the charge density and its gradient, resulting in a meta-GGA. Here, we propose an empirical meta-GGA model that is based both on physical constraints and on experimental and quantum chemistry reference data. The resulting optimized meta-GGA MCML yields improved surface and gas phase reaction energetics without sacrificing the accuracy of bulk property predictions of existing meta-GGA approaches. Kinetic energy ; Density functional theory ; Local-density approximation ; Statistical physics ; Quantum ; Materials science ; Applied mathematics ; Physics ; Computational physics ; Computer science ; Computational chemistry ; Chemistry ; Mathematics ; Quantum mechanics Machine Learning in Materials Science ; Advanced Chemical Physics Studies ; Boron and Carbon Nanomaterials Research