jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Sayantani Nair Nair | Ajith Nair | Arijit Bag | Pradip Kumar Ghorai | Raja Shunmugam
Source: MOJ Current Research & Reviews (article, 2019-06-04)
Field: Materials Science — Biomaterials

Engineering photo cross-linked porous network for efficient and selective removal of toxicants from wastewater This article delineates the UV curable synthesis of an organogel based on thiol-norbornene click chemistry. Characterisations of the material are accomplished by standard analytical and spectroscopic techniques. Rheological measurements suggest the presence of elasticity, which is one of the characteristic features of a gel system. The organogel is found to be mechanically and thermally stable. In particular, the gel shows excellent efficiency towards the removal of cationic dyes from aqueous phase. Additionally, the adsorption results fit with pseudo second order kinetics as well as Langmuir adsorption isotherm model with good correlation. DFT calculations suggest the favourable interaction energy between the dyes and the gel as the defining parameter for the selective uptake of cationic dyes by the gel. To the best of our knowledge, this is the first report unfolding the excellent efficiency of norbornene based photo cross-linked network towards removal of toxic dyes that are regularly discharged from textile and paint industries. Further, minimum water uptake during dye removal process keeps maximum amount of water available for future usage thereby making it an inexpensive material that has potential applications in toxic organic dye containing wastewater treatment. Wastewater ; Porosity ; Environmental science ; Waste management ; Chemistry ; Environmental engineering ; Engineering ; Organic chemistry Supramolecular Self-Assembly in Materials ; Photochromic and Fluorescence Chemistry ; Polydiacetylene-based materials and applications
Authors: Shuqin Bai | Jue Han | Cong Du | Wei Ding
Source: Journal of Water Reuse and Desalination (article, 2019-07-26)
Field: Materials Science — Materials Chemistry

Selective removal of silicic acid by a gallic-acid modified resin Abstract To remove silicic acid from aqueous solutions, a novel gallic acid-type resin (GA-type resin) was prepared by a grafting method. The effects of the adsorption capacity, pH and presence of NaCl, NaNO3, Na2SO4, and NaCO3 salts on the silicic acid removal were studied. The GA-type resin adsorbs monosilicic acid, silicate ions, and polymeric silicic acid. The adsorption capacity of 4.64–4.94 mg/g was achieved in a short adsorption time (Qm of 8.99 mg/g) and is 30–40 times larger than that of the OH-type resin. The silicic acid removal efficiency was almost unaffected by the pH and common anions when the common anion and silicic acid contents were similar, proving the GA-type resin exhibits an excellent performance for selective adsorption of silicic acid. The Temkin isotherm model can well describe the adsorption process, which is chemical adsorption, and indicates that the adsorption heat decreases with the increasing adsorption amount. The adsorption mechanism of silicic acid on the GA-type resin involves dehydration condensation reactions of the hydroxyl groups in silicic acid and gallic acid. The GA-type resin can be efficiently regenerated and reused after treatment with an HCl solution. Silicic acid ; Adsorption ; Chemistry ; Gallic acid ; Silicic ; Inorganic chemistry ; Nuclear chemistry ; Organic chemistry Mesoporous Materials and Catalysis ; Adsorption and biosorption for pollutant removal ; Extraction and Separation Processes
Authors: Manish Wasnik | Tanner C. Livingston | Krista Carlson | Michael F. Simpson
Source: Industrial & Engineering Chemistry Research (article, 2019-07-26)
Field: Chemistry — Inorganic Chemistry

Kinetics of Dechlorination of Molten Chloride Salt Using Protonated Ultrastable Y Zeolite Investigation of the kinetics of the ion exchange between protonated ultrastable Y-type (USHY) and surrogate electrorefiner (ER) waste salt was performed to optimize the dechlorination process. The kinetics of the ion exchange reaction was investigated by measuring the amount of unreacted Cl. In theory, the kinetics of the ion exchange reaction in porous media will be limited by diffusion- or reaction-controlled mechanisms. Therefore, second order kinetics and diffusion-limited rate models have been derived and compared to experimental data to elucidate the rate-limiting step and develop a predictive model for the apparent rate of reaction. Ion exchange experiments were performed with varying zeolite particle sizes (up to 600 μm) at 625 °C. The experiments were performed with both unfluidized and continuously fluidized zeolite particles in static and rotating tube furnaces. It was concluded that the process is limited by reaction kinetics inside the zeolite crystals, and a second order kinetic model best fits the experimental data. Given that the zeolite is not stable at higher temperatures, further increase in the extent of dechlorination for a given batch reaction time requires an increase of the zeolite-to-salt ratio, which has the undesirable effect of increasing the volume of generated waste per amount of salt. Zeolite ; Kinetics ; Chemistry ; Ion exchange ; Chemical kinetics ; Diffusion ; Reaction rate ; Chemical engineering ; Order of reaction ; Salt (chemistry) ; Inorganic chemistry ; Ion ; Catalysis ; Thermodynamics ; Reaction rate constant ; Physical chemistry ; Organic chemistry Zeolite Catalysis and Synthesis ; Iron and Steelmaking Processes ; Molten salt chemistry and electrochemical processes
Authors: Maksym Chylii | T. Malyi | I. Rovetskyi | T. Demkiv | V. Vistovskyy | П. А. Родный | A. Gektin | А. Н. Васильев | A. Voloshinovskiĭ
Source: Optical Materials (article, 2019-03-20)
Field: Materials Science — Materials Chemistry

Diffusion of 5p-holes in BaF2 nanoparticles Luminescence ; Nanoparticle ; Quenching (fluorescence) ; Materials science ; Synchrotron radiation ; Diffusion ; Valence (chemistry) ; Excitation ; Activation energy ; Molecular physics ; Core (optical fiber) ; Analytical Chemistry (journal) ; Chemical physics ; Atomic physics ; Chemistry ; Nanotechnology ; Fluorescence ; Optics ; Physical chemistry ; Optoelectronics ; Thermodynamics ; Physics Luminescence Properties of Advanced Materials ; Radiation Detection and Scintillator Technologies ; Inorganic Fluorides and Related Compounds
Authors: Matthias Bernhard Lierenfeld | Xin Zhong | Éric Reusser | Karsten Kunze | Benita Putlitz | Peter Ulmer
Source: Contributions to Mineralogy and Petrology (article, 2019-05-01)
Field: Materials Science — Biomaterials

Species diffusion in clinopyroxene solid solution in the diopside–anorthite system The coupled multicomponent diffusion of the species Ca2Si2O6, CaAl2SiO6 and Mg2Si2O6 was determined in diopside crystals in the diopside/anorthite (Di/An) system at temperatures (T) of 1110–1260 °C and oxygen fugacities (fO2) between 1.0 log unit below and above the fayalite–magnetite–quartz equilibrium (FMQ ± 1). Diffusion couples were prepared by the seed overgrowth technique. Element concentration profiles were measured perpendicular to the rim/core interface by step-scanning profiling with a field emission gun scanning electron microscope (FEG-SEM). The multicomponent diffusion matrix was solved by fitting its eigenvalues (λ) and eigenvectors (v) to the measured concentration profiles. The full diffusion matrix D can be recovered by using the formula $$D = P\varLambda P^{ - 1}$$ resulting in the following equation: $$D_{\text{Di/An}} = \left[ {\begin{array}{*{20}c} {1.00} & { - 0.67} \\ { - 0.38} & {1.00} \\ \end{array} } \right]\left[ {\begin{array}{*{20}c} {\lambda 1\left( T \right)} & 0 \\ 0 & {\lambda 2\left( T \right)} \\ \end{array} } \right]\left[ {\begin{array}{*{20}c} {1.00} & { - 0.67} \\ { - 0.38} & {1.00} \\ \end{array} } \right]^{ - 1} .$$ The eigenvalues (λ1 and λ2) represent upper limit values and are described by the following Arrhenius-type equations: $$\lambda 1 \left( {\text{Di/An}} \right) = 10^{ - 15.98 \pm 1.17} \times \exp \left[ {\frac{{ - 114.4 \pm 32.8 {\text{kJ/mol}}}}{RT}} \right],$$ $$\lambda 2 \left( {\text{Di/An}} \right) = 10^{ - 16.23 \pm 1.17} \times { \exp }\left[ {\frac{{ - 114.4 \pm 32.8 {\text{kJ/mol}}}}{RT}} \right],$$ where λ1 and λ2 are the first and second eigenvalue of the diffusion matrix in m2 s−1, R is the gas constant and T is the temperature in K. The dominant eigenvalue (λ1) is one quarter order of magnitude larger than the second eigenvalue (λ2). The eigenvectors are constant for all experiments inferring that the entire D matrix can be described with the eigenvalues as the only T-dependent parameter. Additionally, the derived diffusion data and modeling approach were applied to constrain the duration of magmatic processes recorded in zoned clinopyroxene (cpx) phenocrysts from a basaltic, post-plutonic dyke of the Tertiary Adamello batholiths (N-Italy). The results reveal residence times of the overgrown cpx prior to final emplacement in the range of 0.25–1.7 years (lower limit values) testifying that the data and method can be applied to model cpx diffusion profiles in complex natural cpx. Anorthite ; Diopside ; Analytical Chemistry (journal) ; Mineralogy ; Arrhenius equation ; Diffusion ; Lambda ; Crystallography ; Chemistry ; Materials science ; Physics ; Activation energy ; Thermodynamics ; Physical chemistry ; Optics Clay minerals and soil interactions ; Glass properties and applications ; Concrete and Cement Materials Research
Authors: Asuka Inoue | Hiroshi Sugimoto | Minoru Fujii
Source: RSC Advances (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

Silver nanoparticles stabilized with a silicon nanocrystal shell and their antimicrobial activity The antimicrobial activity of a hybrid nanoparticle (NP) composed of a silver (Ag) NP core decorated with silicon (Si) nanocrystals (NCs) on the exterior (Ag/Si NPs) is evaluated. The shell of Si NCs effectively protects the surface of Ag NPs, thus the particles are more stable in water and in air compared to conventional organic-capped Ag NPs. The bacterial growth kinetic analysis reveals that the Si NC shell does not suppress the release of Ag ions from the Ag NP surface due probably to the porous structure. For the antimicrobial coating application, a thin film of the hybrid Ag/Si NPs is produced by drop coating the solution on a cover glass. Thanks to the Si NC shell, agglomeration of Ag NPs in the film is prevented and the film shows a very similar optical absorption spectrum to that of the solution. The film exhibits a larger zone of inhibition in an agar diffusion assay of <i>Escherichia coli</i> compared to a film produced from organic-capped Ag NPs. Nanocrystal ; Antimicrobial ; Shell (structure) ; Nanoparticle ; Nanotechnology ; Materials science ; Silicon ; Silver nanoparticle ; Chemistry ; Chemical engineering ; Optoelectronics ; Organic chemistry ; Composite material Nanoparticles: synthesis and applications ; Laser-Ablation Synthesis of Nanoparticles ; Graphene and Nanomaterials Applications
Authors: Aneta Buczek | Dawid Siodłak | M. Bujak | Maciej Makowski | Teobald Kupka | Małgorzata A. Broda
Source: Structural Chemistry (article, 2019-07-18)
Field: Chemistry — Spectroscopy

Impact of the ΔPhe configuration on the Boc-Gly-ΔPhe-NHMe conformation: experiment and theory Conformational propensities of N-t-butoxycarbonyl-glycine-(E/Z)-dehydrophenylalanine N′-methylamides (Boc-Gly-(E/Z)-ΔPhe-NHMe) in chloroform were investigated by NMR and IR techniques. The low-temperature crystal structure of the E isomer was determined by single crystal X-ray diffraction and the experimental data were elaborated by theoretical calculations using DFT (B3LYP, M06-2X) and MP2 approaches. The β-turn tendencies for both isomers were determined in the gas phase and in the presence of solvent. The obtained results reveal that the configuration of ΔPhe residue significantly affects the conformations of the studied dehydropeptides. The tendency to adopt β-turn conformations is significantly lower for the E isomer (Boc-Gly-(E)-ΔPhe-NHMe), both in gas phase and in chloroform solution. Chemistry ; Chloroform ; Residue (chemistry) ; Gas phase ; Solvent ; Single crystal ; Crystallography ; Crystal structure ; Glycine ; Turn (biochemistry) ; Stereochemistry ; Computational chemistry ; Amino acid ; Physical chemistry ; Organic chemistry Mass Spectrometry Techniques and Applications ; Chemical Synthesis and Analysis ; Protein Structure and Dynamics
Authors: Lereze Marais | Anél Petzer | Jacobus P. Petzer | Lesetja J. Legoabe
Source: Molecular Diversity (article, 2019-05-21)
Field: Chemistry — Organic Chemistry

The monoamine oxidase inhibition properties of C6- and N1-substituted 3-methyl-3,4-dihydroquinazolin-2(1H)-one derivatives Quinazolinone ; Monoamine oxidase ; Potency ; Chemistry ; IC50 ; Stereochemistry ; In vitro ; Combinatorial chemistry ; Enzyme ; Biochemistry Quinazolinone synthesis and applications ; Synthesis and Biological Evaluation ; Adenosine and Purinergic Signaling
Authors: Bogdan Dereka | Ina Fureraj | Arnulf Rosspeintner | Eric Vauthey
Source: Molecules (article, 2019-11-29)
Field: Chemistry — Physical and Theoretical Chemistry

Halogen-Bond Assisted Photoinduced Electron Transfer The formation of a halogen-bond (XB) complex in the excited state was recently reported with a quadrupolar acceptor-donor-acceptor dye in two iodine-based liquids (<i>J. Phys. Chem. Lett.</i> <b>2017</b>, <i>8</i>, 3927-3932). The ultrafast decay of this excited complex to the ground state was ascribed to an electron transfer quenching by the XB donors. We examined the mechanism of this process by investigating the quenching dynamics of the dye in the S<sub>1</sub> state using the same two iodo-compounds diluted in inert solvents. The results were compared with those obtained with a non-halogenated electron acceptor, fumaronitrile. Whereas quenching by fumaronitrile was found to be diffusion controlled, that by the two XB compounds is slower, despite a larger driving force for electron transfer. A Smoluchowski-Collins-Kimball analysis of the excited-state population decays reveals that both the intrinsic quenching rate constant and the quenching radius are significantly smaller with the XB compounds. These results point to much stronger orientational constraint for quenching with the XB compounds, indicating that electron transfer occurs upon formation of the halogen bond. Photochemistry ; Excited state ; Chemistry ; Quenching (fluorescence) ; Electron transfer ; Electron acceptor ; Acceptor ; Photoinduced electron transfer ; Halogen ; Population ; Electron donor ; Chemical physics ; Fluorescence ; Atomic physics ; Organic chemistry ; Catalysis Photochemistry and Electron Transfer Studies ; Radical Photochemical Reactions ; Spectroscopy and Quantum Chemical Studies
Authors: Nail S. Akhmadiev | Albina Midkhatovna Galimova | В. Р. Ахметова | В. Р. Хайруллина | Р. А. Галимова | Eduard F. Agletdinov | А. Г. Ибрагимов | Valery Alekseevich Kataev
Source: Advanced Pharmaceutical Bulletin (article, 2019-06-08)
Field: Chemistry — Organic Chemistry

Molecular Docking and Preclinical Study of Five-MemberedS,S-Palladaheterocycle as Hepatoprotective Agent <i><b>Purpose:</b></i> In order to investigate mechanisms underlying the hepatoprotective action of S,Spalladaheterocycle, inhibition of cytochromes P450 has been modeled by molecular docking of four palladaheterocycle stereoisomers to the active sites of an enzymatic oxidase system. To obtain a deeper insight into biochemical aspects providing a basis for the therapeutic effects of five-membered palladacycles (as mixture of stereoisomers), a number of preclinical trials has been conducted <i><b>Methods:</b></i> 2D and 3D structures of palladaheterocycle stereoisomers were obtained via converting into SDF files by means of software MarvinSketch. Binding of palladaheterocycle at the active sites of cytochromes P450 2E1 and P450 2C9 has been studied by molecular docking using LeadIT 2.3.2. Hepatoprotective activity of palladaheterocycle at 2.5, 25 and 250 mg/kg doses has been studied based on a model of acute intoxication by CCl<sub>4</sub> using <i>in vivo</i> methods. <i><b>Results:</b></i> By molecular docking it was identify amino acid fragments responsible for binding with palladacyclic isomers. The tested compound is comparable, in terms of its activity to the hepatoprotective drug SAM according to the <i>in vivo</i> and <i>in vitro</i> experiments such as animal survival data, the efficiency of correction of the cytolytic syndrome, the liver excretory function, carbohydrate, protein and lipid metabolism, and the correction efficiency of the liver antitoxic function (the latter has been determined based on the results of a hexobarbital control experiment). <i><b>Conclusion:</b></i> Taking into account results obtained <i>in vivo, in vitro</i> and in silico, it can be concluded that the five-membered S,S-palladaheterocycle effectively protect the liver against acute damage caused by CCl<sub>4</sub> , via activation of catalase and glucuronyltransferase, as well as via inhibition of the oxidative stress enzymes. Docking (animal) ; Pharmacology ; Chemistry ; Traditional medicine ; Medicine ; Computational biology ; Biology ; Veterinary medicine Sulfur-Based Synthesis Techniques ; Sulfur Compounds in Biology ; Organoselenium and organotellurium chemistry
Authors: Lisette M.J. Sprakel | Boelo Schuur
Source: Journal of Molecular Liquids (article, 2019-03-16)
Field: Chemistry — Physical and Theoretical Chemistry

Molecular design and engineering for affinity separation processes using isothermal titration calorimetry (ITC) and molecular modeling (MM) Isothermal titration calorimetry ; Chemistry ; Enthalpy ; Calorimetry ; Solvent ; Alkyl ; Isothermal process ; Thermodynamics ; Titration ; Physical chemistry ; Organic chemistry thermodynamics and calorimetric analyses ; Analytical Chemistry and Chromatography ; Chemical Thermodynamics and Molecular Structure
Authors: Marc Riera | Eric Yeh | Francesco Paesani
Source: ChemRxiv (preprint, 2019-12-05)
Field: Materials Science — Materials Chemistry

Data-Driven Many-Body Models for Molecular Fluids: CO2/H2O Mixtures as a Case Study In this study, we extend the scope of the many-body TTM-nrg and MB-nrg potential energy functions (PEFs), originally introduced for halide ion–water and alkali-metal ion–water interactions, to the modeling of carbon dioxide (CO2) and water (H2O) mixtures as prototypical examples of molecular fluids. Both TTM-nrg and MB-nrg PEFs are derived entirely from electronic structure data obtained at the coupled cluster level of theory and are, by construction, compatible with MB-pol, a many-body PEF that has been shown to accurately reproduce the properties of water. Although both TTM-nrg and MB-nrg PEFs adopt the same functional forms for describing permanent electrostatics, polarization, and dispersion, they differ in the representation of short-range contributions, with the TTM-nrg PEFs relying on conventional Born-Mayer expressions and the MB-nrg PEFs employing multidimensional permutationally invariant polynomials. By providing a physically correct description of many-body effects at both short and long ranges, the MB-nrg PEFs are shown to quantitatively represent the global potential energy surfaces of the CO2–CO2 and CO2–H2O dimers and the energetics of small clusters as well as to correctly reproduce various properties in both gas and liquid phases. Building upon previous studies of aqueous systems, our analysis provides further evidence for the accuracy and efficiency of the MB-nrg framework in representing molecular interactions in fluid mixtures at different temperature and pressure conditions. Chemistry ; London dispersion force ; Chemical physics ; Molecular dynamics ; Statistical physics ; Thermodynamics ; Physics ; Computational chemistry ; Molecule ; van der Waals force Machine Learning in Materials Science ; Protein Structure and Dynamics ; Phase Equilibria and Thermodynamics
Authors: Huijie Tian | Christopher Rzepa | Ronak Upadhyay | Srinivas Rangarajan
Source: AIChE Journal (article, 2019-10-16)
Field: Materials Science — Materials Chemistry

Estimating vibrational and thermodynamic properties of adsorbates with uncertainty using data driven surrogates Abstract In this work, we propose a strategy to develop data driven local surrogate models of ab initio potential energy functions describing the interaction of adsorbates on heterogeneous catalytic materials. We show that these multivariable surrogate models, based on orthogonal polynomial expansion and trained on sampled ab‐initio energies/forces, can be used to compute harmonic vibrational frequencies and the entropy of adsorbates. Further, we show that the errors in our surrogate model can be estimated and propagated to calculate the uncertainty in the computed properties. We show proof‐of‐concept illustrations of our method to calculate the vibrational frequencies of ethene on 1D edges of molybdenum sulfide (MoS 2 ), (b) 2D surfaces of Pt(111), and (c) 3D micropores of a HZSM‐5 zeolite; the entropy of ethane adsorbed on Pt(111); and the associated uncertainties in all the cases. Ab initio ; Thermodynamics ; Chemistry ; Entropy (arrow of time) ; Zeolite ; Statistical physics ; Polynomial ; Computational chemistry ; Catalysis ; Physics ; Mathematics ; Mathematical analysis ; Organic chemistry Machine Learning in Materials Science ; Advanced Chemical Physics Studies ; Zeolite Catalysis and Synthesis
Authors: D.P. Michael Mingos
Source: CHIMIA International Journal for Chemistry (article, 2019-03-20)
Field: Chemistry — Physical and Theoretical Chemistry

Development of Bonding Models Based on the Periodic Table Kossel and Lewis' description of the chemical bonding in ionic and covalent compounds in 1916 made an important contribution, which connected the Periodic Table to modern valence theory. In a 1919 paper Langmuir made the perceptive observation that neutral molecules, which had the same number of electrons, e.g. N₂ and CO and N₂O and CO₂, had remarkably similar physico-chemical properties. Inorganic chemists have used this isoelectronic principle to interconnect a wide range of compounds and thereby explore the implications of the Periodic Table. Periodic table ; Ionic bonding ; Covalent bond ; Chemical bond ; Table (database) ; Molecule ; Valence electron ; Chemical physics ; Valence (chemistry) ; Electron ; Valence bond theory ; Range (aeronautics) ; Interconnection ; Computational chemistry ; Chemistry ; Atomic physics ; Nanotechnology ; Crystallography ; Materials science ; Physics ; Computer science ; Ion ; Organic chemistry ; Quantum mechanics ; Molecular orbital History and advancements in chemistry ; Chemistry and Chemical Engineering ; Computational Drug Discovery Methods