jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ben A. Johnson | Sascha Ott
Source: Chemical Science (article, 2020-01-01)
Field: Chemistry — Inorganic Chemistry

Diagnosing surface <i>versus</i> bulk reactivity for molecular catalysis within metal–organic frameworks using a quantitative kinetic model Metal-organic frameworks (MOFs) are becoming increasingly popular as heterogenous support matrices for molecular catalysts. Given that reactants, or potentially holes/electrons, need to diffuse into the porous framework as the reaction proceeds, the reaction can possibly take place within the bulk of the particle or be confined to a thin layer at the surface due to transport limitations. Herein, a simple steady-state reaction-diffusion kinetic model is developed to diagnose these two mutually exclusive behaviors in MOF-based systems. The oxygen evolution reaction (OER) driven by a chemical oxidant is presented as an example mechanism. Quantitative metrics for assigning either bulk or surface reactivity are delineated over a wide variety of conditions, and numerical simulations are employed to verify these results. For each case, expressions for the turnover frequency (TOF) are outlined, and it is shown that surface reactivity can influence measured TOFs. Importantly, this report shows how to transition from surface to bulk reactivity and thus identifies which experimental parameters to target for optimizing the efficiency of MOF-based molecular catalyst systems. Catalysis ; Limiting ; Reactivity (psychology) ; Kinetic energy ; Chemistry ; Mass transport ; Metal-organic framework ; Chemical physics ; Computational chemistry ; Nanotechnology ; Materials science ; Physical chemistry ; Biochemical engineering ; Organic chemistry ; Physics ; Engineering Metal-Organic Frameworks: Synthesis and Applications ; Machine Learning in Materials Science ; Catalytic Processes in Materials Science
Authors: Ștefania Racoviță | Nicolae Baranov | Ana‐Maria Macsim | Cătălina Lionte | Corina Cheptea | Valeriu Şunel | Marcel Popa | Silvia Vasiliu | Jacques Desbrières
Source: Molecules (article, 2020-11-20)
Field: Materials Science — Biomaterials

New Grafted Copolymers Carrying Betaine Units Based on Gellan and N-Vinylimidazole as Precursors for Design of Drug Delivery Systems New grafted copolymers possessing structural units of 1-vinyl-3-(1-carboxymethyl) imidazolium betaine were obtained by graft copolymerization of <i>N</i>-vinylimidazole onto gellan gum followed by the polymer-analogous reactions on grafted polymer with the highest grafting percentage using sodium chloroacetate as the betainization agent. The grafted copolymers were prepared using ammonium persulfate/<i>N</i>,<i>N</i>,<i>N</i>',<i>N</i>' tetramethylethylenediamine in a nitrogen atmosphere. The grafting reaction conditions were optimized by changing one of the following reaction parameters: initiator concentration, monomer concentration, polymer concentration, reaction time or temperature, while the other parameters remained constant. The highest grafting yield was obtained under the following reaction conditions: c<sub>i</sub> = 0.08 mol/L, c<sub>m</sub> = 0.8 mol/L, c<sub>p</sub> = 8 g/L, t<sub>r</sub> = 4 h and T = 50 °C. The kinetics of the graft copolymerization of <i>N</i>-vinylimidazole onto gellan was discussed and a suitable reaction mechanism was proposed. The evidence of the grafting reaction was confirmed through FTIR spectroscopy, X-ray diffraction, <sup>1</sup>H-NMR spectroscopy and scanning electron microscopy. The grafted copolymer with betaine structure was obtained by a nucleophilic substitution reaction where the betainization agent was sodium chloroacetate. Preliminary results prove the ability of the grafted copolymers to bind amphoteric drugs (cefotaxime) and, therefore, the possibility of developing the new sustained drug release systems. Copolymer ; Betaine ; Polymer chemistry ; Chemistry ; Grafting ; Monomer ; Fourier transform infrared spectroscopy ; Ammonium persulfate ; Polymer ; Styrene ; Nuclear chemistry ; Organic chemistry ; Chemical engineering biodegradable polymer synthesis and properties ; Hydrogels: synthesis, properties, applications ; Electrospun Nanofibers in Biomedical Applications
Authors: Ying Tang | Zhaoyi Li | Zhongying Xu | Jie Zhang | Chengtun Qu | Zhifang Zhang
Source: RSC Advances (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Synthesis of hierarchical MgO based on a cotton template and its adsorption properties for efficient treatment of oilfield wastewater A biomorphic MgO nanomaterial was fabricated <i>via</i> a facile and low-cost immersion method using cotton as the template. The obtained materials were characterized <i>via</i> X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and N<sub>2</sub> adsorption-desorption analysis. The as-prepared MgO retained the structure of cotton, with a porous hierarchical structure and a high specific surface area, which endowed it with great potential due to its excellent adsorption properties for the adsorption of additives in oil field wastewater. It also exhibited the maximum adsorption capacity of 391.36 mg g<sup>-1</sup> for sulfonated lignite. The adsorption process of sulfonated lignite on biomorphic MgO was systematically investigated and was found to obey the pseudo-second-order rate equation and the Langmuir adsorption model. The negative values of Gibbs free energy change (Δ<i>G</i>) showed that the adsorption process was feasible and spontaneous. The endothermic process was depicted with a positive value for Δ<i>H</i>. Adsorption ; Nanomaterials ; Wastewater ; Materials science ; Chemical engineering ; Nanotechnology ; Pulp and paper industry ; Chemistry ; Environmental science ; Organic chemistry ; Environmental engineering ; Engineering Magnesium Oxide Properties and Applications ; Calcium Carbonate Crystallization and Inhibition
Authors: Mohammad Hadi Nafar Sefiddashti | Brian J. Edwards | Bamin Khomami
Source: Physical Review Research (article, 2020-01-10)
Field: Materials Science — Polymers and Plastics

Flow-induced crystallization of a polyethylene liquid above the melting temperature and its nonequilibrium phase diagram Virtual experimentation involving atomistic simulation of a polyethylene melt undergoing elongational flow reveals a biphasic flow profile exhibiting a phase transition from an oriented liquid to a semicrystalline solid at high field strength. This flow-induced crystalline phase occurs at temperatures high above the quiescent melting point and appears to be reversible. A nonequilibrium phase diagram can be constructed exhibiting multiple stable and metastable states corresponding to coiled and stretched liquid states and semicrystalline solid phases with varying degrees of crystallinity and morphologies Crystallinity ; Phase diagram ; Metastability ; Materials science ; Polyethylene ; Crystallization ; Non-equilibrium thermodynamics ; Thermodynamics ; Melting point ; Phase (matter) ; Crystallization of polymers ; Flow (mathematics) ; Phase transition ; Mechanics ; Composite material ; Chemistry ; Organic chemistry ; Physics Polymer crystallization and properties ; Rheology and Fluid Dynamics Studies ; Material Dynamics and Properties
Authors: Mingming Gu | Aman Satija | Robert P. Lucht
Source: Proceedings of the Combustion Institute (article, 2020-08-15)
Field: Chemistry — Spectroscopy

CO2 chirped-probe-pulse femtosecond CARS thermometry Femtosecond ; Materials science ; Laser ; Raman scattering ; Pulse (music) ; Temperature measurement ; Optics ; Raman spectroscopy ; Physics ; Detector Spectroscopy and Laser Applications ; Combustion and flame dynamics ; Spectroscopy Techniques in Biomedical and Chemical Research
Authors: Raju Bathula | Shobha Rani Satla | Ramadevi Kyatham | Kiran Gangarapu
Source: Asian Pacific Journal of Cancer Prevention (article, 2020-02-01)
Field: Chemistry — Organic Chemistry

Design, One Pot Synthesis and Molecular Docking Studies of Substituted-1H-Pyrido[2,1-b] Quinazolines as Apoptosis-Inducing Anticancer Agents Overall, these findings could suggest that the compound 4i would be an ideal lead as an anticancer agent. Quinazoline ; Chemistry ; Ethidium bromide ; A549 cell ; Apoptosis ; Acridine orange ; Stereochemistry ; Quinazolinone ; Cell culture ; Pharmacophore ; Cytotoxicity ; Clonogenic assay ; Cancer cell ; In vitro ; Biochemistry ; Biology ; Cancer Quinazolinone synthesis and applications ; Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Gurdeep | Phool Chandra | Neetu Sachan
Source: International Journal of Pharmaceutical Sciences Review and Research (review, 2020-11-15)
Field: Chemistry — Organic Chemistry

Chemistry and Pharmacological Activities of Pyrazole and Pyrazole Derivatives: A Review At the heart of current research is the battle for more efficient and less toxic treatment approaches for diseases. Pyrazole and its derivatives have emerged as an influential scaffold that has drawn the attention of researchers in the field of medicinal chemistry due to its appreciable diversity in biological activities. Pyrazole derivatives have found numerous applications in fluorescent substances, dyes, and agrochemicals. Pyrazole is a multifunction lead compound for efficient biologically active molecules generated by researchers. They have shown a widespread biological and pharmacological activity such as antitumor, analgesic, antiinflammatory, antimicrobial, antitubercular, antileishmanial activity, ACE inhibitors, antidiabetic, antiparkinsonian and neuroprotective properties. This rational diversity in the pattern of physiological reaction has led many scientists, with far more successful pharmacological intervention, to refine and create new structural alternatives. This Review is important for previous studies and initiatives to explore in the near future the various activities of compounds associated with pyrazole and pyrazole derivatives. Pyrazole ; Chemistry ; Combinatorial chemistry ; Medicinal chemistry Synthesis and biological activity ; Multicomponent Synthesis of Heterocycles ; Computational Drug Discovery Methods
Authors: Bastiaan D. Ippel | Muhabbat I. Komil | Paul A. A. Bartels | Serge H. M. Söntjens | Roy J. E. A. Boonen | Maarten M. J. Smulders | Patricia Y. W. Dankers
Source: Macromolecules (article, 2020-05-26)
Field: Materials Science — Surfaces, Coatings and Films

Supramolecular Additive-Initiated Controlled Atom Transfer Radical Polymerization of Zwitterionic Polymers on Ureido-pyrimidinone-Based Biomaterial Surfaces Surface-initiated controlled radical polymerization is a popular technique for the modification of biomaterials with, for example, antifouling polymers. Here, we report on the functionalization of a supramolecular biomaterial with zwitterionic poly(sulfobetaine methacrylate) via atom transfer radical polymerization from a macroinitiator additive, which is embedded in the hard phase of the ureido-pyrimidinone-based material. Poly(sulfobetaine methacrylate) was successfully polymerized from these surfaces, and the polymerized sulfobetaine content, with corresponding antifouling properties, depended on both the macroinitiator additive concentration and polymerization time. Furthermore, the polymerization from the macroinitiator additive was successfully translated to functional electrospun scaffolds, showing the potential for this functionalization strategy in supramolecular material systems. Atom-transfer radical-polymerization ; Polymerization ; Polymer chemistry ; Radical polymerization ; Surface modification ; Reversible addition−fragmentation chain-transfer polymerization ; Methacrylate ; Chemistry ; Polymer ; Supramolecular chemistry ; Biomaterial ; Supramolecular polymers ; Materials science ; Chain transfer ; Organic chemistry ; Molecule ; Physical chemistry Polymer Surface Interaction Studies ; Marine Biology and Environmental Chemistry ; Advanced Polymer Synthesis and Characterization
Authors: Maryam Sheybanifard | Nataliia Beztsinna | Mahsa Bagheri | Eva Miriam Buhl | Jaleesa Bresseleers | Aida Varela-Moreira | Yang Shi | Cornelus F. van Nostrum | Gabri van der Pluijm | Gert Storm | Wim E. Hennink | Twan Lammers | Josbert M. Metselaar
Source: International Journal of Pharmaceutics (article, 2020-05-07)
Field: Materials Science — Biomaterials

Systematic evaluation of design features enables efficient selection of Π electron-stabilized polymeric micelles Paclitaxel ; Ethylene glycol ; Polymer ; In vivo ; Methacrylamide ; Micelle ; Chemistry ; Copolymer ; Materials science ; Organic chemistry ; Aqueous solution Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; Lanthanide and Transition Metal Complexes
Authors: Liu, X. | Meijer, G. | Pérez-Ríos, J.
Source: MPG.PuRe (Max Planck Society) (article, 2020-11-14)
Field: Materials Science — Materials Chemistry

A data-driven approach to determine dipole moments of diatomic molecules We present a data-driven approach for the prediction of the electric dipole moment of diatomic molecules, which is one of the most relevant molecular properties. In particular, we apply Gaussian process regression to a novel dataset to show that dipole moments of diatomic molecules can be learned, and hence predicted, with a relative error ≲5%. The dataset contains the dipole moment of 162 diatomic molecules, the most exhaustive and unbiased dataset of dipole moments up to date. Our findings show that the dipole moment of diatomic molecules depends on atomic properties of the constituents atoms: electron affinity and ionization potential, as well as on (a feature related to) the first derivative of the electronic kinetic energy at the equilibrium distance. Diatomic molecule ; Dipole ; Bond dipole moment ; Moment (physics) ; Electric dipole moment ; Transition dipole moment ; Chemistry ; Atomic physics ; Gaussian ; Molecule ; Physics ; Computational chemistry ; Quantum mechanics Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Protein Structure and Dynamics
Authors: Eamonn F. Healy | Glenn Blade
Source: Journal of Chemical Education (article, 2020-07-31)
Field: Chemistry — Physical and Theoretical Chemistry

Tips and Tools for Teaching Organic Synthesis Online While synthesis projects are not uncommon in the undergraduate organic curriculum, the problems posed are usually not representative of what chemists actually do. The sudden dislocation to online learning precipitated by the COVID-19 pandemic provided both a need and an opportunity to develop an organic synthesis project with greater relevance to both the times and the discipline. Utilizing a state-of-the-art artificial intelligence model accessible to the undergraduate through a fully interactive platform, a project was designed involving molecules of both pharmaceutical relevance and topical interest, and suitable for online instruction. Technological and pedagogical issues posed by the online delivery of this content are discussed, as are issues related to student engagement. Relevance (law) ; Coronavirus disease 2019 (COVID-19) ; Curriculum ; 2019-20 coronavirus outbreak ; Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ; Computer science ; Engineering ethics ; Psychology ; Engineering ; Pedagogy ; Political science ; Medicine Various Chemistry Research Topics ; Innovative Teaching Methods ; Problem and Project Based Learning
Authors: Erkan Konca
Source: Metals (article, 2020-03-28)
Field: Materials Science — Materials Chemistry

A Comparison of the Ballistic Performances of Various Microstructures in MIL-A-12560 Armor Steel Due to their advantageous properties, there is a growing interest in developing armor steels containing fully or partially bainitic microstructures. In this study, bainitic and martensitic microstructures were obtained in rolled homogeneous armor (RHA) steel samples and their ballistic protection performances were investigated. RHA (MIL-A-12560) steel samples were subjected to isothermal heat treatments at three different temperatures, where one temperature (360 °C) was above the martensite formation start (Ms) temperature of 336 °C while the other two (320 °C and 270 °C) were below. For the assessment of the ballistic protection performance, the kinetic energy losses of the 12.7 mm bullets fired at the test samples were determined. The promising nature of the bainite microstructure was confirmed as the sample isothermally treated at 360 °C provided approximately 10% higher ballistic protection as compared to the regular RHA sample of tempered martensite microstructure. However, the ballistic performances of the isothermally treated samples decreased as the treatment temperature went below the Ms temperature. Following the ballistic tests, hardness measurements, impact tests at −40 °C, and macro- and microstructural examinations of the samples were performed. No correlation was found between the hardness and impact energies of the samples and their ballistic performances. Microstructure ; Martensite ; Materials science ; Bainite ; Isothermal process ; Armour ; Metallurgy ; Composite material ; Homogeneous ; Layer (electronics) ; Thermodynamics High-Velocity Impact and Material Behavior ; Microstructure and Mechanical Properties of Steels ; High-pressure geophysics and materials
Authors: Ali Ayadi | Mélanie Auffan | Jérôme Rose
Source: Procedia Computer Science (article, 2020-01-01)
Field: Chemistry — Physical and Theoretical Chemistry

Ontology-based NLP information extraction to enrich nanomaterial environmental exposure database In recent years, nanotechnologies have led to undeniable progress in any domains, such as electronics, materials and medicine. Despite the benefits of such a technology, a careful assessment of the potential risks for Human and Environmental health have to be studied. Assessing exposure and hazard to nanomaterials is a major challenge in the field of environmental sciences. This task requires to gather a large amount of meaningful experimental data usually generated by laboratory experiments. A first database of environmental exposure to nanomaterials (EXPOSED database) has been developed to gather data generated during mesocosm experiments. The challenge is now to enrich this database with more data from scientific articles in related fields. Herein, we present an ontology-based Natural Language Processing (NLP) approach to automatically extract and transfer data from text sources to database. This approach combines the use of NLP techniques and a domain ontology to automatically extract environmental exposure and hazards information. This approach was tested to enrich the EXPOSED database and indicators of quality highlight that this approach is effective and promising. Computer science ; Ontology ; Data science ; Field (mathematics) ; Information extraction ; Information retrieval ; Database History and advancements in chemistry ; Biomedical Text Mining and Ontologies ; Data Quality and Management
Authors: Ahmed Abdi Hassan | Ismail Abdulazeez | Omobayo A. Salawu | Abdul‐Rahman Al‐Betar
Source: SN Applied Sciences (article, 2020-06-20)
Field: Materials Science — Polymers and Plastics

Electrochemical deposition and characterization of polyaniline-grafted graphene oxide on a glassy carbon electrode Polyaniline ; Graphene ; Materials science ; Oxide ; Polyaniline nanofibers ; Glassy carbon ; Chemical engineering ; Electrochemistry ; Graphene oxide paper ; Fourier transform infrared spectroscopy ; Raman spectroscopy ; Electrode ; Nanotechnology ; Cyclic voltammetry ; Chemistry ; Composite material ; Polymer ; Metallurgy ; Polymerization Conducting polymers and applications ; Electrochemical sensors and biosensors ; Analytical Chemistry and Sensors
Authors: Rahul Rao | Jennifer Carpena‐Núñez | Nicholas T. Dee | Dmitri N. Zakharov | J. Anibal Boscoboinik | Eric A. Stach | A. John Hart | Benji Maruyama
Source: Carbon (article, 2020-04-23)
Field: Materials Science — Materials Chemistry

Maximization of carbon nanotube yield by solid carbon-assisted dewetting of iron catalyst films Dewetting ; Carbon nanotube ; Materials science ; Catalysis ; Chemical engineering ; Carbon fibers ; Yield (engineering) ; Chemical vapor deposition ; Raman spectroscopy ; Nanotechnology ; Nucleation ; Chemistry ; Composite material ; Thin film ; Organic chemistry ; Composite number Carbon Nanotubes in Composites ; Chemical and Physical Properties of Materials ; nanoparticles nucleation surface interactions
Authors: Manabu Nakaya | Ryo Ohtani | Shinya Hayami
Source: European Journal of Inorganic Chemistry (article, 2020-08-30)
Field: Chemistry — Inorganic Chemistry

Guest Modulated Spin States of Metal Complex Assemblies Recently, “host–guest chemistry” aspects of material science have received much attention, particularly in relation to moderating the functions of materials. In particular, magnetic properties involving the “magnetic ordering” and “spin crossover” of host–guest metal complex systems have been actively investigated in terms of their host–guest chemistry. That is, systems in which the magnetic properties are sensitive to perturbation by the uptake of guests (which thus act as chemical stimuli). Such guests (solvents, gases and organic molecules) very often influence the structures of both discrete metallosupramolecular assemblies as well as those of coordination polymers/metal‐organic frameworks (CPs/MOFs), providing a means for fine‐tuning their magnetic behavior, including the switching of their spin states. In this minireview, we report recent progress in the development and investigation of magnetic materials of both the CP and MOF categories as well as of discrete complexes whose properties are modulated by guests. Chemistry ; Spin crossover ; Metal-organic framework ; Polymer ; Nanotechnology ; Coordination complex ; Metal ; Chemical physics ; Supramolecular chemistry ; Molecule ; Inorganic chemistry ; Physical chemistry ; Organic chemistry ; Materials science Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes
Authors: Fábio M. F. Santos | Zoe Domínguez | João Pedro Fernandes | Cátia Parente Carvalho | Daniel Collado | Ezequiel Pérez‐Inestrosa | Maria V. Pinto | Adelaide Fernandes | Jesús F. Arteaga | Uwe Pischel | Pedro M. P. Góis
Source: Chemistry - A European Journal (article, 2020-05-25)
Field: Materials Science — Materials Chemistry

Cyanine‐Like Boronic Acid‐Derived Salicylidenehydrazone Complexes (Cy‐BASHY) for Bioimaging Applications Boronic acid-derived salicylidenehydrazone complex (BASHY) dyes with a polymethine backbone were designed to yield efficient red-emitting and two-photon absorbing fluorophores that can be used as markers for astrocytes. The dyes are chemically stable in aqueous solution and do not undergo photodecomposition. Their photophysical properties can be electronically fine-tuned and thereby adapted to potentially different imaging situations and requirements. Cyanine ; Boronic acid ; Aqueous solution ; Yield (engineering) ; Chemistry ; Photochemistry ; Combinatorial chemistry ; Aqueous medium ; Organic chemistry ; Materials science ; Fluorescence ; Optics Luminescence and Fluorescent Materials ; Nanoplatforms for cancer theranostics ; Molecular Sensors and Ion Detection