jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Katarzyna Trzeciak | Ewelina Wielgus | Sławomir Kaźmierski | Tomasz Pawlak | Marek J. Potrzebowski
Source: Pharmaceutics (article, 2023-04-13)
Field: Chemistry — Spectroscopy

Amorphization of Ethenzamide and Ethenzamide Cocrystals—A Case Study of Single and Binary Systems Forming Low-Melting Eutectic Phases Loaded on/in Silica Gel The applicability of different solvent-free approaches leading to the amorphization of active pharmaceutical ingredients (APIs) was tested. Ethenzamide (ET), an analgesic and anti-inflammatory drug, and two ethenzamide cocrystals with glutaric acid (GLU) and ethyl malonic acid (EMA) as coformers were used as pharmaceutical models. Calcinated and thermally untreated silica gel was applied as an amorphous reagent. Three methods were used to prepare the samples: manual physical mixing, melting, and grinding in a ball mill. The ET:GLU and ET:EMA cocrystals forming low-melting eutectic phases were selected as the best candidates for testing amorphization by thermal treatment. The progress and degree of amorphousness were determined using instrumental techniques: solid-state NMR spectroscopy, powder X-ray diffraction, and differential scanning calorimetry. In each case, the API amorphization was complete and the process was irreversible. A comparative analysis of the dissolution profiles showed that the dissolution kinetics for each sample are significantly different. The nature and mechanism of this distinction are discussed. Differential scanning calorimetry ; Eutectic system ; Materials science ; Dissolution ; Reagent ; Chemical engineering ; Thermal analysis ; Amorphous solid ; Pharmaceutics ; Mechanochemistry ; Cocrystal ; Crystallography ; Organic chemistry ; Chemistry ; Thermodynamics ; Nanotechnology ; Thermal ; Molecule ; Microstructure ; Metallurgy ; Hydrogen bond Advanced NMR Techniques and Applications ; Crystallography and molecular interactions ; Drug Solubulity and Delivery Systems
Authors: Dinesh Bhalothia | Amisha Beniwal | Praveen Kumar Saravanan | Guo-Heng Huang | Mingxing Cheng | Ming-Wei Lin | Po‐Chun Chen | Tsan‐Yao Chen
Source: Materials Advances (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Facile surface restructure by one-step sub-millisecond laser exposure promotes the CO<sub>2</sub> methanation performance of cobalt oxide supported Pd nanoparticles with copper-oxide cluster decoration The schematic representation for the atomic structures of pristine CPCu, CPCu-1 and CPCu-10 nanocatalysts. Methanation ; Nanomaterial-based catalyst ; Oxide ; Cobalt ; Materials science ; Cobalt oxide ; Nanoparticle ; Schematic ; Cluster (spacecraft) ; Millisecond ; Copper ; Copper oxide ; Chemical engineering ; Nanotechnology ; Inorganic chemistry ; Catalysis ; Chemistry ; Metallurgy ; Computer science Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions ; Catalysts for Methane Reforming
Authors: J. Woods | Lucía Gallego | Amira Maisch | Dominik Renggli | Corrado Cuocci | Olivier Blacque | Gunther Steinfeld | Andres Kaech | Bernhard Spingler | Andreas Vargas Jentzsch | Michel Rickhaus
Source: ChemRxiv (preprint, 2023-04-12)
Field: Materials Science — Biomaterials

Saddles as rotational locks within shape-assisted self-assembled nanosheets Two-dimensional (2D) materials are a key target for many applications in the modern day. Self-assembly is one approach that can bring us closer to this goal, which usually relies upon strong, directional interactions instead of covalent bonds. Control over less directional forces is more challenging and usually does not result in as well-defined materials. Explicitly incorporating topography into the design as a guiding effect to enhance the interacting forces can help to form highly ordered structures. Herein, we show the process of shape-assisted self-assembly to be consistent across a range of derivatives that highlights the restriction of rotational motion. A shape governed angle distribution nurtures monomers into loose columns that then arrange to form 2D structures with long-range order observed in both crystalline and soft materials. These features strengthen the idea that shape becomes an important design principle leading towards precise molecular self-assembly and the inception of new materials. Self-assembly ; Rotation around a fixed axis ; Nanotechnology ; Process (computing) ; Range (aeronautics) ; Order (exchange) ; Motion (physics) ; Computer science ; Materials science ; Physics ; Classical mechanics Supramolecular Self-Assembly in Materials ; Advanced Materials and Mechanics ; Calcium Carbonate Crystallization and Inhibition
Authors: Pietro Mandracci | Paola Rivolo
Source: Preprints.org (preprint, 2023-05-05)
Field: Materials Science — Materials Chemistry

Recent Advances in the Plasma-Assisted Synthesis of Silicon-Based Thin-Films and Nanostructures Silicon-based thin-films and nanostructures are of paramount importance in a wide range of applications, including microelectronics, photovoltaics, large area sensors, as well as biomedicine. The wide accessibility of silicon and its relatively low cost have driven a continuous improvement of the technology based on this element. Plasma technology has been widely used for the synthesis of coatings and nanostructures based on silicon. Moreover, it has given a fundamental contribution for continuously improving the control of the physicochemical properties of silicon-based materials, and for allowing the synthesis of nanometric structures with well-defined shape and morphology. In this work, we have reviewed the most interesting developments of plasma-assisted processed for the synthesis of Si-based materials, both inorganic and organic, in the last five years. A special attention has been given to the new techniques, or modifications of already existing ones, that open new possibilities for the synthesis of materials with new properties, as well as nanostructures with novel characteristics. Microelectronics ; Silicon ; Nanotechnology ; Materials science ; Nanostructure ; Photovoltaics ; Plasma ; Photovoltaic system ; Optoelectronics ; Engineering ; Electrical engineering ; Physics Silicon Nanostructures and Photoluminescence ; Semiconductor materials and devices ; Diamond and Carbon-based Materials Research
Authors: Md Shakeel Ahmed | Ameena Parveen | Sriram Manjunath
Source: Mechanical Engineering Advances (article, 2023-12-15)
Field: Materials Science — Polymers and Plastics

Mechanical properties of polypyrrole/SnO2 nanocomposites and its LPG sensing application Polypyrrole/SnO2 nanocomposites were created using in-situ polymerization techniques. The nanocomposites were described using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and their thermal properties were studied using a Differential Scanning Calorimeter (DSC). The DC conductivity of the samples was measured as a function of temperature from 30 ℃ to 1900 ℃, and it was observed that increasing the concentration of tin oxide particles improves conductivity due to polaron hopping and composite chain length extension. The tensile strength of PPy nanocomposites doped in PVA thin film up to 6 wt% indicates 64.2 MPa, which may be related to the homogenous distribution of PPy nanocomposite in PVA. The study reveals that because 50 wt% of the nanocomposites have the highest conductivity and sensitivity, these nanocomposites may be useful in future applications. Nanocomposite ; Materials science ; Polypyrrole ; Scanning electron microscope ; Differential scanning calorimetry ; Ultimate tensile strength ; Composite material ; Conductivity ; Transmission electron microscopy ; Tin oxide ; Doping ; Polymerization ; Polymer ; Nanotechnology ; Chemistry Conducting polymers and applications ; Advanced Sensor and Energy Harvesting Materials ; Analytical Chemistry and Sensors
Authors: Tianyu Li | Luyao Ding | Yihong Kang | Xin‐Qi Hao | Yujing Guo | Linlin Shi | Mao‐Ping Song
Source: Chemical Synthesis (article, 2023-10-31)
Field: Chemistry — Spectroscopy

The synthesis, characterization and application of the binol-cages of R-/S-enantiomers In the past few years, significant efforts have been made to create and self-assemble covalent organic cages with increased complexity and functionality. However, although supramolecule cages have been widely recognized as probes to identify metal ions, the detection of mercury ions has not been fully developed. Here, we have designed and synthesized a pair of chiral cages with custom cavities based on the unique rigid structure of 1, 10-binaphthol (binol). Meanwhile, the supramolecular cage has excellent performance in high sensitivity and selectivity for detecting mercury ions. The UV titration results indicate that the binding ratio of the host to guest is 1:5. The titration curve conforms to the nonlinear fitting of the Hill function, which can obtain the binding constant K = 2.57 × 105 M-1 . Furthermore, the detection limit of 1.9 × 10-7 M can be obtained because the absorbance of cages exhibits a strong linear relationship with Hg2+ concentrations. This work provides a new method for selective recognition of ions by supramolecular cages. Supramolecular chemistry ; Absorbance ; Titration ; Metal ions in aqueous solution ; Detection limit ; Enantiomer ; Ion ; Selectivity ; Binding constant ; Covalent bond ; Chemistry ; Nonlinear optical ; Materials science ; Crystallography ; Nanotechnology ; Physical chemistry ; Stereochemistry ; Crystal structure ; Binding site ; Organic chemistry ; Chromatography ; Nonlinear system ; Physics Molecular Sensors and Ion Detection ; Supramolecular Chemistry and Complexes ; Porphyrin and Phthalocyanine Chemistry
Authors: Milena L. Czyz | Tyra H. Horngren | Andrew J. Kondopoulos | Liam J. Franov | José A. Forni | Le Nhan Pham | Michelle L. Coote | Anastasios Polyzos
Source: ChemRxiv (preprint, 2023-10-25)
Field: Chemistry — Organic Chemistry

Photocatalytic Generation of Alkyl Carbanions from Alkenes Organometallic reagents are routinely used as fundamental building blocks in organic chemistry to rapidly diversify molecular fragments via carbanion intermediates. However the catalytic generation of carbanion equivalents particularly from sp3-hybridized alkyl scaffolds, remains an underdeveloped goal in chemical synthesis. To align with the demands of modern synthetic protocols, a general method for the catalytic generation of alkyl carbanions must operate under benign reaction conditions and access commercially available feedstock chemicals. Alkenes constitute an attractive source of latent alkyl carbanion equivalents, however methods for the conversion of carbon-carbon bonds into carbanions is challenged by the need for precious metals and aggressive stoichiometric reductants. Here we disclose an approach for the controlled generation of 2-electron carbon nucleophiles via single electron reduction of aryl alkenes, facilitated by the highly reducing environment of multiphoton photoredox catalysts. We demonstrate that alkene radical anions engage in catalytic, metal free, intermolecular C-C bond-forming reactions with carbonyl derivatives, in a manner analogous to Grignard reagents. Under this reaction manifold, the alkene can be considered a dicarbanion synthon offering new opportunities for orthogonal diversification. This concept was illustrated by the development of four distinct C-C bond forming reactions with aromatic alkenes: hydroalkoxylation, hydroamidation, aminoalkylation and carboxyaminoalkylation, to generate a range of valuable and complex scaffolds. Carbanion ; Alkene ; Chemistry ; Photoredox catalysis ; Alkyl ; Synthon ; Catalysis ; Organic synthesis ; Nucleophile ; Combinatorial chemistry ; Organic chemistry ; Reagent ; Photochemistry ; Photocatalysis Catalytic C–H Functionalization Methods ; Radical Photochemical Reactions ; Sulfur-Based Synthesis Techniques
Authors: Maria‐Gabriela Alexandru | Diana Visinescu | Sergiu Shova | Joan Cano | Nicolás Moliner | Francesc Lloret | Miguel Julve
Source: Magnetochemistry (article, 2023-05-15)
Field: Materials Science — Electronic, Optical and Magnetic Materials

A Chain of Vertex-Sharing {CoIII2CoII2}n Squares with Single-Ion Magnet Behavior A new mixed-valence one-dimensional coordination polymer of formula {[CoII(MeOH)2][(μ-NC)2CoIII(dmphen)(CN)2]2}n·2nH2O (1) was obtained by reacting the Ph4P[CoII(dmphen)(CN)3] metalloligand (dmphen = 2,9-dimethyl-1,10-phenanthroline and Ph4P+ = tetraphenylphosphonium ion) with cobalt(II) acetate tetrahydrate. The structural analysis shows the formation of a neutral 4,2-ribbon-like chain of vertex-sharing cyanido-bridged {CoIII2CoII2} squares in which the metalloligand underwent an oxidation process and a reorganization to form {CoIII(dmphen)(CN)4}− linkers that coordinate to the [CoII(MeOH)2]2+ units through single cyanido ligands. Both cobalt(II) and Co(III) cations are six-coordinated in distorted octahedral environments. The shortest intrachain distance between the paramagnetic cobalt(II) ions is 7.36 Å, a value which is shorter than the shortest interchain one (10.36 Å). Variable-temperature (1.9–300 K) static (dc) magnetic measurements for 1 indicate the occurrence of magnetically isolated high-spin cobalt(II) ions with a D value of +67.0 cm−1. Dynamic alternating current (ac) magnetic measurements between 2.0–13 K reveal that 1 exhibits slow magnetic relaxation under non-zero applied dc fields, being thus a new example of field-induced SIM with easy-plane magnetic anisotropy. Theoretical calculations by CASSCF/NEVPT2 on 1 support the results from magnetometry. The relaxation of the magnetization occurs in the ground state under external dc fields through a two-phonon Raman process and one intra-Kramers mechanism. Chemistry ; Cobalt ; Crystallography ; Ion ; Magnetization ; Paramagnetism ; Valence (chemistry) ; Octahedron ; Magnetic anisotropy ; Magnetic field ; Condensed matter physics ; Crystal structure ; Inorganic chemistry ; Physics Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Organic and Molecular Conductors Research
Authors: Darío Puchán Sánchez | Pierre Josse | Monika Mutovska | Benjamin Siegler | Magali Allain | Korentin Morice | Philippe Blanchard | Frédéric Gohier | Tangui Le Bahers | Cyrille Monnereau | Yulian Zagranyarski | Dominik Lungerich | Clément Cabanetos
Source: ChemistryEurope (article, 2023-11-27)
Field: Chemistry — Organic Chemistry

Radical‐Formation Management: Towards Aza‐Analogues of the Benzothioxanthene Imide Abstract While benzothioxanthene imide ( BTI ) has shown promise in organic electronics and more recently in photodynamic therapy, its full potential remains yet undiscovered. In this context, this study repots the synthesis and characterization of aza derivatives in which the characteristic sulfur atom is replaced by an amino group. Adapted from the synthetic route of the BTI , a way was found to control the electronic structure of the radical intermediates, by means of a simple chemical modification. As a result, either the thermodynamically six‐membered or the kinetically favored five‐membered ring regioisomers can selectively be accessed. Photophysical rationalization of their structure‐property relationships confirmed the richness, versatility and tunability of this class of rylene imide‐based dyes. Imide ; Chemistry ; Context (archaeology) ; Combinatorial chemistry ; Stereochemistry ; Organic chemistry Radical Photochemical Reactions ; Sulfur-Based Synthesis Techniques ; Organic Light-Emitting Diodes Research
Authors: Hidetoshi Noda | Yasuko Asada | Masakatsu Shibasaki
Source: Frontiers in Chemistry (article, 2023-11-03)
Field: Chemistry — Organic Chemistry

Examining the effects of additives and precursors on the reactivity of rhodium alkyl nitrenes generated from substituted hydroxylamines In this study, the reactivity of the alkyl nitrenes, generated from the substituted hydroxylamine precursors, was determined using the same rhodium catalyst. The results revealed that in competitive C-H insertion experiments, the regioselectivity between benzylic and tertiary C-H bonds could be modulated by adding Brønsted acids or changing the substituents on oxygen. This study enhances our understanding of the metallonitrene structures and provides valuable insights for further development of selective N-heterocycle syntheses. Regioselectivity ; Nitrene ; Reactivity (psychology) ; Rhodium ; Alkyl ; Hydroxylamine ; Chemistry ; Catalysis ; Organic chemistry ; Medicinal chemistry ; Stereochemistry Synthesis and Catalytic Reactions ; Catalytic C–H Functionalization Methods ; Cyclopropane Reaction Mechanisms
Authors: Anshul Baral | Haiyan Zhu | Bradford A. Moffat | Santanu Chattopadhyay | Francesca Cavalieri | Muthupandian Ashokkumar
Source: Materials Advances (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

Ultrasound-driven fabrication of hybrid magnetic tryptophan nanoparticles A facile sonochemical method to fabricate magnetic tryptophan-iron oxide nanoparticles for biomedical applications. Nanoparticle ; Magnetic nanoparticles ; Tryptophan ; Nanotechnology ; Iron oxide nanoparticles ; Fabrication ; Iron oxide ; Materials science ; Ultrasound ; Chemistry ; Medicine ; Metallurgy ; Biochemistry Pickering emulsions and particle stabilization ; Hydrogels: synthesis, properties, applications ; Nanoparticle-Based Drug Delivery
Authors: Sung Ho Kim | Ate Visser | Noelle R. Catarineu | Aaron B. Bantug | Simon H. Pang | A. Garenne | Erik Oerter | Theodore F. Baumann | M. Heffner | S. Sangiorgio
Source: Microporous and Mesoporous Materials (article, 2023-11-28)
Field: Chemistry — Inorganic Chemistry

High yield, large-scale synthesis of calcium-based microporous metal-organic framework and examination of the long-term stability for xenon adsorption applications Yield (engineering) ; Microporous material ; Reagent ; Chemistry ; Adsorption ; Inorganic chemistry ; Materials science ; Organic chemistry ; Metallurgy Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Enhanced Oil Recovery Techniques
Authors: Debashis Dhara | Laurence A. Mulard | Marcel Hollenstein
Source: Carbohydrate Research (article, 2023-11-20)
Field: Chemistry — Organic Chemistry

Expedient synthesis of l-heptose derived septacidin building blocks from l-glucose Chemistry ; Alkene ; Azide ; Moiety ; Combinatorial chemistry ; Osmium ; Yield (engineering) ; Diol ; Stereochemistry ; Organic chemistry ; Catalysis ; Ruthenium Carbohydrate Chemistry and Synthesis ; Glycosylation and Glycoproteins Research ; Cancer therapeutics and mechanisms
Authors: Liecheng Guo | Huiping Zhang | Yongming Xia | Lele Gong | Lipeng Zhang | Feng Luo
Source: Science China Materials (article, 2023-05-29)
Field: Chemistry — Inorganic Chemistry

Employing metal-organic cage for selective capture of UO22+ and Sr2+ Uranyl ; Extraction (chemistry) ; Carboxylate ; Ion ; Octahedron ; Ligand (biochemistry) ; Adsorption ; Materials science ; Metal ; Selectivity ; Metal ions in aqueous solution ; Chemistry ; Inorganic chemistry ; Physical chemistry ; Chromatography ; Stereochemistry ; Organic chemistry ; Metallurgy Radioactive element chemistry and processing ; Chemical Synthesis and Characterization ; Lanthanide and Transition Metal Complexes
Authors: Joel Boaretto | R. C. D. Cruz | Felipe Vannucchi de Camargo | Guilherme Luís Cordeiro | Cristiano Fragassa | Carlos Pérez Bergmann
Source: Polymers (review, 2023-09-08)
Field: Materials Science — Polymers and Plastics

Using Thermomechanical Properties to Reassess Particles’ Dispersion in Nanostructured Polymers: Size vs. Content Nanoparticle-filled polymers (i.e., nanocomposites) can exhibit characteristics unattainable by the unfilled polymer, making them attractive to engineer structural composites. However, the transition of particulate fillers from the micron to the nanoscale requires a comprehensive understanding of how particle downsizing influences molecular interactions and organization across multiple length scales, ranging from chemical bonding to microstructural evolution. This work outlines the advancements described in the literature that have become relevant and have shaped today's understanding of the processing-structure-property relationships in polymer nanocomposites. The main inorganic and organic particles that have been incorporated into polymers are examined first. The commonly practiced methods for nanoparticle incorporation are then highlighted. The development in mechanical properties-such as tensile strength, storage modulus and glass transition temperature-in the selected epoxy matrix nanocomposites described in the literature was specifically reviewed and discussed. The significant effect of particle content, dispersion, size, and mean free path on thermomechanical properties, commonly expressed as a function of weight percentage (wt.%) of added particles, was found to be better explained as a function of particle crowding (number of particles and distance among them). From this work, it was possible to conclude that the dramatic effect of particle size for the same tiny amount of very small and well-dispersed particles brings evidence that particle size and the particle weight content should be downscaled together. Materials science ; Glass transition ; Composite material ; Particle size ; Polymer ; Nanocomposite ; Ultimate tensile strength ; Nanoparticle ; Particle (ecology) ; Dispersion (optics) ; Dynamic mechanical analysis ; Polymer nanocomposite ; Nanotechnology ; Chemical engineering Polymer Nanocomposites and Properties ; Nanotechnology research and applications ; Polymer crystallization and properties
Authors: Yvonne Lerchbammer-Kreith | Michaela Hejl | Nadine S. Sommerfeld | Xian Weng-Jiang | Uchechukwu Odunze | Ryan Mellor | David G. Workman | Michael A. Jakupec | Andreas G. Schätzlein | Ijeoma F. Uchegbu | M. Galanski | Bernhard K. Keppler
Source: Pharmaceuticals (article, 2023-07-19)
Field: Materials Science — Polymers and Plastics

Quaternary Ammonium Palmitoyl Glycol Chitosan (GCPQ) Loaded with Platinum-Based Anticancer Agents—A Novel Polymer Formulation for Anticancer Therapy Quaternary ammonium palmitoyl glycol chitosan (GCPQ) has already shown beneficial drug delivery properties and has been studied as a carrier for anticancer agents. Consequently, we synthesised cytotoxic platinum(IV) conjugates of cisplatin, carboplatin and oxaliplatin by coupling via amide bonds to five GCPQ polymers differing in their degree of palmitoylation and quaternisation. The conjugates were characterised by <sup>1</sup>H and <sup>195</sup>Pt NMR spectroscopy as well as inductively coupled plasma mass spectrometry (ICP-MS), the latter to determine the amount of platinum(IV) units per GCPQ polymer. Cytotoxicity was evaluated by the MTT assay in three human cancer cell lines (A549, non-small-cell lung carcinoma; CH1/PA-1, ovarian teratocarcinoma; SW480, colon adenocarcinoma). All conjugates displayed a high increase in their cytotoxic activity by factors of up to 286 times compared to their corresponding platinum(IV) complexes and mostly outperformed the respective platinum(II) counterparts by factors of up to 20 times, also taking into account the respective loading of platinum(IV) units per GCPQ polymer. Finally, a biodistribution experiment was performed with an oxaliplatin-based GCPQ conjugate in non-tumour-bearing BALB/c mice revealing an increased accumulation in lung tissue. These findings open promising opportunities for further tumouricidal activity studies especially focusing on lung tissue. Oxaliplatin ; Carboplatin ; Chemistry ; Conjugate ; Cisplatin ; Cytotoxicity ; MTT assay ; Platinum ; Combinatorial chemistry ; Nuclear chemistry ; Biochemistry ; Cell growth ; Cancer ; Chemotherapy ; Medicine ; Colorectal cancer ; In vitro Dendrimers and Hyperbranched Polymers ; Nanoparticle-Based Drug Delivery ; Polymer Surface Interaction Studies