jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Xiaoli Liu | Andres Ortega‐Guerrero | Nency P. Domingues | Miriam Pougin | Berend Smit | Leticia Hosta‐Rigau | Chris Oostenbrink
Source: Langmuir (article, 2024-10-12)
Field: Chemistry — Inorganic Chemistry

Stability Assessment in Aqueous and Organic Solvents of Metal–Organic Framework PCN 333 Nanoparticles through a Combination of Physicochemical Characterization and Computational Simulations Mesoporous metal-organic frameworks (MOFs) have been recognized as powerful platforms for drug delivery, especially for biomolecules. Unfortunately, the application of MOFs is restricted due to their relatively poor stability in aqueous media, which is crucial for drug delivery applications. An exception is the porous coordination network (PCN)-series (e.g., PCN-333 and PCN-332), a series of MOFs with outstanding stability in aqueous media at the pH range from 3 to 9. In this study, we fabricate PCN-333 nanoparticles (nPCN) and investigate their stability in different solvents, including water, ethanol, and methanol. Surprisingly, the experimental characterizations in terms of X-ray diffraction, Brunauer-Emmett-Teller (BET), and scanning electron microscopy demonstrated that nPCN is not as stable in water as previously reported. Specifically, the crystalline structure of nPCN lost its typical octahedral shape and even decomposed into an irregular amorphous form when exposed to water for only 2 h, but not when ethanol and methanol were used. Meanwhile, the porosity of nPCN substantially diminished while being exposed to water, as demonstrated by the BET measurement. With the assistance of computational simulations, the mechanism behind the collapse of PCN-333 is illuminated. By molecular dynamics simulation and umbrella sampling, we elucidate that the degradation of PCN-333 occurs by hydrolysis, wherein polar solvent molecules initiate the attack and subsequent breakage of the metal-ligand reversible coordination bonds. Aqueous solution ; Chemistry ; Metal-organic framework ; Mesoporous material ; Nanoparticle ; Chemical engineering ; Amorphous solid ; Solvent ; Molecule ; Nanotechnology ; Inorganic chemistry ; Materials science ; Organic chemistry ; Catalysis Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; X-ray Diffraction in Crystallography
Authors: Chao Tan | Jian Shang | Zhen Li
Source: Physics of Fluids (article, 2024-04-01)
Field: Materials Science — Materials Chemistry

Simulation of cavitation erosion damage and structural evolution caused by nano-bubbles for iron In this work, the dynamic behavior of nano-bubbles near the surface of single crystal iron (Fe) was investigated using molecular dynamics simulations. The cavitation erosion behavior of single crystal Fe and the structural evolution of its eroded surface was examined at different bubble diameters. The results show that nano-bubble diameter is inversely correlated with impact pressure and diameter is positively correlated with nanojet energy. The volume, surface area, and depth of cavitation pits are nearly directly proportional to the bubble diameter with correlation linear fitting coefficients of R2 = 0.9837, R2 = 0.9922, and R2 = 0.9799, respectively. Additionally, cavitation erosion induces the structural evolution of iron atoms from bcc to fcc and hcp structures. The percentage of new phase transformed is related to the bubble diameter and the type of transformed structure, the percentage of fcc and hcp structures of Fe atoms exhibits an increasing trend with the increase in the bubble diameter, and the Fe atoms of fcc structures occur an obvious increase beyond a bubble diameter of 12 nm. Cavitation ; Cavitation erosion ; Erosion ; Nano- ; Geology ; Materials science ; Forensic engineering ; Geotechnical engineering ; Mechanics ; Engineering ; Composite material ; Geomorphology ; Physics Ultrasound and Cavitation Phenomena ; Cavitation Phenomena in Pumps ; Erosion and Abrasive Machining
Authors: P.J. Canfield | Jeffrey R. Reimers | Maxwell J. Crossley
Source: ACS Organic & Inorganic Au (review, 2024-03-27)
Field: Chemistry — Spectroscopy

“Polytopal Rearrangement Model of Stereoisomerization” and Its Potential as the Basis for a Systematic Model of All Stereoisomerism The term "polytopal rearrangement" describes any shape changing process operating on a coordination "polyhedron"-the solid figure defined by the positions of the ligand atoms directly attached to the central atom of a coordination entity. Developed in the latter third of the last century, the polytopal rearrangement model of stereoisomerization is a general mathematical approach for analyzing and accommodating the complexity of such processes for any coordination number. The motivation for the model was principally to deal with the complexity, such as Berry pseudorotation in pentavalent phosphorus species, arising from rearrangements in inorganic coordination complexes of higher coordination numbers. The model is also applicable to lower coordination centers, for example, thermal "inversion" at nitrogen in NH<sub>3</sub> and amines. We present the history of the model focusing on its essential features, and review some of the more subtle aspects addressed in recent literature. We then introduce a more detailed and rigorous modern approach for describing such processes using an assembly of existing concepts, with the addition of formally described terminology and representations. In our outlook, we contend that the rigorous and exhaustive application of the principles of the polytopal rearrangement model, when combined with torsional isomerism, will provide a basis for a mathematically complete, general, and systematic classification for all stereoisomerism and stereoisomerization. This is essential for comprehensively mapping chemical structure and reaction spaces. Basis (linear algebra) ; Computational biology ; Biology ; Mathematics Molecular spectroscopy and chirality ; Chemical Synthesis and Analysis ; Enzyme Catalysis and Immobilization
Authors: Saliha Belhouchat | Samira Zeroual | Noura Benbellat | Oussama Khaoua | Saad Bouchekioua | Rafik Menacer | Henry Chermette
Source: ChemistrySelect (article, 2024-01-07)
Field: Materials Science — Electronic, Optical and Magnetic Materials

DFT and Docking Calculations of the Structural, Electronic, Biological and Conductivity Properties of the Synthetic Complex [Cu(hfac) <sub>2</sub> (L) <sub>2</sub> ][PF <sub>6</sub> ] <sub>2</sub> Abstract In the present research, we report a theoretical study of Cu II complex based on TTF ligand [Cu(hfac) 2 (L) 2 ][PF 6 ] 2 (in neutral and oxidized states +1 and +2, of biological interest and various applications in magnetic conducting materials. It is an organic/inorganic hybrid material involving a coordination between a paramagnetic transition metal and a nitrogenous aromatic TTF linked through a covalent transition conjugate bridge. The optimized structures of neutral and oxidized metal transition complexes obtained using the Density Functional Theory (DFT) method are consistent with the experimental results. Several properties including geometrical parameters, Hirshfeld atomic charges, energies of Frontier Molecular Orbitals (FMOs), and energy gap (ΔEgap) between the Highest Occupied Molecular Orbital (HOMO), and the Lowest Unoccupied Molecular Orbital (LUMO) are calculated for optimized complexes. The results reveal that oxidation leads to more stable aromatic systems and reduces the energy gap. The analysis of the charges as well as the distribution of the spin density in the frontier orbitals shows that the oxidation takes place at the ligand level. More precisely the ylidene C3=C4 bond is the most sensitive molecular part to oxidation. A significant degeneracy of molecular orbitals is also observed. No metallic contribution in the HOMO of Cu complex reveals a strong electronic localization at the end of the chain, and, at the same time a delocalization along the chain, this is also in favor of a good conductivity and excellent catalytic activity of this compounds. Molecular orbital ; HOMO/LUMO ; Delocalized electron ; Density functional theory ; Chemistry ; Atomic orbital ; Covalent bond ; Transition metal ; Computational chemistry ; Molecular orbital diagram ; Chemical physics ; Crystallography ; Basis set ; Molecule ; Catalysis ; Physics ; Electron ; Linear combination of atomic orbitals Magnetism in coordination complexes ; Organic and Molecular Conductors Research ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Yuce Li | Jing He | Jixiu Liu | Wooram Um | Jianxun Ding
Source: Nanomedicine (review, 2024-10-09)
Field: Materials Science — Biomaterials

Challenges and opportunities of poly(amino acid) nanomedicines in cancer therapy Poly(amino acid) nanomedicines hold significant promise for cancer therapy. However, their clinical translation has not matched the extensive efforts of scientists or the burgeoning body of research. The therapeutic outcomes with most nanomedicines often fall short of the promising results observed in animal experiments. This review explores the challenges faced in cancer therapy using poly(amino acid) nanomedicines, particularly addressing the controversies surrounding the enhanced permeability and retention effect and the lack of methods for controlled and reproducible mass production of poly(amino acid) nanomedicines. Furthermore, this review examines the opportunities emerging in this field due to the rapid advancements in artificial intelligence. Cancer therapy ; Cancer ; Nanotechnology ; Amino acid ; Nanomedicine ; Medicine ; Materials science ; Chemistry ; Nanoparticle ; Internal medicine ; Biochemistry Nanoparticle-Based Drug Delivery ; RNA Interference and Gene Delivery ; Dendrimers and Hyperbranched Polymers
Authors: Wael Z. Tawfik | Mohamed Sh. Abdel-wahab | June Key Lee | Abdullah M. Al‐Enizi | Rasha Y Youssef
Source: Physica Scripta (article, 2024-05-20)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Modeling specific capacitance of carbon nanotube-based supercapacitor electrodes by machine learning algorithms Abstract Carbon nanotubes (CNTs) have emerged as promising materials for supercapacitors (SCs) due to their unique properties and exceptional electrical conductivity. These cylindrical structures composed of carbon atoms offer several advantages for SC electrode applications. The electrochemical performance of CNT-based electrodes is strongly influenced by factors such as surface area, pore structure, and I D /I G ratio. However, the lack of a credible physical model capable of accurately predicting the performance of SCs based on these physicochemical properties of CNTs poses a challenge. In this study, we propose the utilization of a data-driven approach employing various models including a gradient boosting regression (GBR), Bayesian regression (BR), ridge regression (RR), and stochastic gradient descent (SGD) model to predict the performance of SCs with CNT electrodes based on the microstructural properties of the electrode material and electrochemical operational parameters. The developed GBR model demonstrates its feasibility by achieving a low root mean square error (RMSE) value of approximately 36.31 for the prediction of specific capacitance for test split. Additionally, a sensitivity analysis was conducted to investigate the influence of independent input parameters on a single output parameter, specifically the specific capacitance. This analysis provides insights into the relative importance and impact of various input parameters on the specific capacitance of CNT-based SCs. Supercapacitor ; Capacitance ; Carbon nanotube ; Materials science ; Electrode ; Nanotechnology ; Computer science ; Physics Supercapacitor Materials and Fabrication ; Fuel Cells and Related Materials
Authors: Marta A. Teixeira | Mariana P. Barreiros | Helena P. Felgueiras | Raúl Fangueiro | Diana P. Ferreira
Source: Cellulose (article, 2024-11-25)
Field: Materials Science — Biomaterials

Unlocking the potential of nanocellulose from textile waste: a pathway to nanocomposite applications Abstract Global textile consumption has increased significantly in the last decades and, consequently, millions of tons of textile waste have been discarded every year. Landfills and incinerators are their main fates, causing several and significant environmental problems. Cotton, second to polyester, is the most widely used fibre in the textile industry. Therefore, the recovery of this fibre from wastes is an imperative waste management strategy to mitigate the environmental impacts related with their disposable as well as its farming. Various approaches have been employed to reuse these waste cotton textiles. The extraction of cellulose nanomaterials, such as cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs) from these solid wastes has shown to be a promising methodology. Owing to its outstanding and natural properties, nanocellulose applications have gained high attraction in different areas. In this review, the potential of using waste cotton textiles to extract nanocellulose instead of other cellulosic resources is highlighted and discussed. The concept of nanocellulose and the differences between types is well clarified. A background on the typically applied extraction methods is presented, giving special relevance to those already employed to extract nanocellulose from textile wastes, in particular those containing cotton. In addition, limitations to these methodologies are also examined, as well as possible applications of the extracted nanocellulose on high value-added products. Nanocellulose ; Textile ; Nanocomposite ; Materials science ; Pulp and paper industry ; Composite material ; Polymer science ; Cellulose ; Chemical engineering ; Engineering Advanced Cellulose Research Studies ; Nanocomposite Films for Food Packaging
Authors: Jacob M. Wozniak | Weichao Li | Christopher G. Parker
Source: Trends in Pharmacological Sciences (review, 2024-10-14)
Field: Chemistry — Organic Chemistry

Chemical proteomic mapping of reversible small molecule binding sites in native systems Small molecule ; Chemistry ; Computational biology ; Molecule ; Biophysics ; Biology ; Biochemistry ; Organic chemistry Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Monoclonal and Polyclonal Antibodies Research
Authors: Sanjun Fan | Brian T. Scarpitti | Zhewen Luo | Abigail E. Smith | Jian Ye | Zachary D. Schultz
Source: Nano Research (article, 2024-07-02)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Facile synthesis of intra-nanogap enhanced Raman tags with different shapes Hot spot engineering in plasmonic nanostructures plays a significant role in surface enhanced Raman scattering for bioanalysis and cell imaging. However, creating stable, reproducible, and strong SERS signals remains challenging due to the potential interference from surrounding chemicals and locating SERS-active analytes into hot-spot regions. Herein, we developed a straightforward approach to synthesize intra-gap nanoparticles encapsulating 4-nitrobenzenethiol (4-NBT) as a reporter molecule within these gaps to avoid outside interference. We made three kinds of intra-gap nanoparticles using nanorods, bipyramids, and nanospheres as cores, in which the nanorod based intra-gap nanoparticles exhibit the highest SERS activity. The advantage of our method is the ease of preparation of high-yield and stable intra-gap nanoparticles characterized by a short incubation time (10 mins) with 4-NBT and quick synthesis without requiring an additional step to centrifuge for the purification of core nanoparticles. The intense localized field in the synthesized hot spots of these plasmonic gap nanostructures holds great promise as a SERS substrate for a broad range of quantitative optical applications. Raman spectroscopy ; Materials science ; Nanotechnology ; Optics ; Physics Gold and Silver Nanoparticles Synthesis and Applications ; Plasmonic and Surface Plasmon Research ; Near-Field Optical Microscopy
Authors: Mariana Sardo | Tiago Morais | Márcio Soares | Ricardo Vieira | Marina Ilkaeva | Mirtha A. O. Lourenço | Ildefonso Marín-Montesinos | Luís Mafra
Source: Chemical Communications (article, 2024-01-01)
Field: Chemistry — Spectroscopy

Unravelling the structure of CO<sub>2</sub> in silica adsorbents: an NMR and computational perspective This comprehensive review describes recent advancements in the use of solid-state NMR-assisted methods and computational modeling strategies to unravel gas adsorption mechanisms and CO<sub>2</sub> speciation in porous CO<sub>2</sub>-adsorbent silica materials at the atomic scale. This work provides new perspectives for the innovative modifications of these materials rendering them more amenable to the use of advanced NMR methods. Adsorption ; Solid-state ; Solid-state nuclear magnetic resonance ; Genetic algorithm ; Porosity ; Perspective (graphical) ; Materials science ; Chemistry ; Nanotechnology ; Physical chemistry ; Computer science ; Organic chemistry ; Physics ; Nuclear magnetic resonance Advanced NMR Techniques and Applications ; Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis
Authors: Yoichi Hoshimoto | Mahiro Sakuraba
Source: Synthesis (article, 2024-08-19)
Field: Chemistry — Organic Chemistry

Recent Trends in Triarylborane Chemistry: Diversification of Structures and Reactivity via meta-Substitution of the Aryl Groups Abstract This Short Review summarizes the synthesis and applications of triarylboranes (BAr3), including both homoleptic and heteroleptic species, with a focus on the modification of their electronic and structural properties via the introduction of meta-substituents with respect to the B atoms to their Ar groups. This approach constitutes a complementary alternative to conventional strategies for the design of BAr3, which are usually based on a modification of their ortho- and/or para-substituents. An initial analysis revealed that CH3 and F are the most common meta-substituents in hitherto reported BAr3 (apart from the H atom). Thus, an extensive exploration of other substituents, e.g., heavier halogens, longer or functionalized alkyl groups, and aryl groups, will increase our knowledge of the structure and reactivity of BAr3 and eventually lead to a range of new applications. 1 Introduction 2 Scope of this Review 2.1 The Electronic and Steric Influence of meta-Substituents 2.2 Molecular Transformations Mediated by meta-Substituted Boranes 2.3 Other Examples of meta-Functionalization of BAr3 3 Conclusions and Perspectives Chemistry ; Aryl ; Substitution (logic) ; Reactivity (psychology) ; Diversification (marketing strategy) ; Substitution reaction ; Organic chemistry ; Medicinal chemistry ; Alkyl Organoboron and organosilicon chemistry ; Boron Compounds in Chemistry ; Sulfur-Based Synthesis Techniques
Authors: Tannaz Alamfard | Tommy Lorenz | Cornelia Breitkopf
Source: Polymers (article, 2024-01-30)
Field: Materials Science — Polymers and Plastics

Glass Transition Temperatures and Thermal Conductivities of Polybutadiene Crosslinked with Randomly Distributed Sulfur Chains Using Molecular Dynamic Simulation The thermal conductivities and glass transition temperatures of polybutadiene crosslinked with randomly distributed sulfur chains having different lengths from mono-sulfur (S1) to octa-sulfur (S8) were investigated. The thermal conductivities of the related models as a function of the heat flux autocorrelation function, applying an equilibrium molecular dynamic (EMD) simulation and the Green-Kubo method, were studied for a wide range of temperatures. The influence of the length of sulfur chains, degree of crosslinking, and molar mass of the crosslinker on the glass transition temperature and final values of thermal conductivities were studied. First, the degree of crosslinking is considered constant for the eight simulation models, from mono-sulfur (S1) to octa-sulfur (S8), while the molar mass of the sulfur is increases. The results show that the thermal conductivities of the crosslinked structure decrease with increasing temperature for each model. Moreover, by increasing the lengths of the sulfur chains and the molar weight of the crosslinker, thermal conductivity increases at a constant temperature. The MD simulation demonstrates that the glass transition temperature and density of the crosslinked structure enhance as the length of the sulfur chains and molar mass of the sulfur increase. Second, the molar weight of sulfur is considered constant in these eight models; therefore, the degree of crosslinking decreases with the increase in the lengths of the sulfur chains. The results show that the thermal conductivities of the crosslinked structure decrease with the increase in the temperature for each model. Moreover, by increasing the lengths of sulfur chains and thus decreasing the degree of crosslinking, the trend in changes in thermal conductivities are almost the same for all of these models, so thermal conductivity is constant for a specific temperature. In addition, the glass transition temperature and density of the crosslinked structure decrease. Polybutadiene ; Glass transition ; Materials science ; Sulfur ; Thermal ; Thermal conductivity ; Polymer chemistry ; Polymer ; Chemical engineering ; Composite material ; Thermodynamics ; Copolymer ; Physics Polymer crystallization and properties ; Organic Electronics and Photovoltaics ; Thermal properties of materials
Authors: Matthew G. Boebinger | Dündar E. Yılmaz | Ayana Ghosh | Sudhajit Misra | Tyler S. Mathis | Sergei V. Kalinin | Stephen Jesse | Yury Gogotsi | Adri C. T. van Duin | Raymond R. Unocic
Source: Small Methods (article, 2024-05-28)
Field: Materials Science — Materials Chemistry

Direct Fabrication of Atomically Defined Pores in MXenes Using Feedback‐Driven STEM Controlled fabrication of nanopores in 2D materials offer the means to create robust membranes needed for ion transport and nanofiltration. Techniques for creating nanopores have relied upon either plasma etching or direct irradiation; however, aberration-corrected scanning transmission electron microscopy (STEM) offers the advantage of combining a sub-Å sized electron beam for atomic manipulation along with atomic resolution imaging. Here, a method for automated nanopore fabrication is utilized with real-time atomic visualization to enhance the mechanistic understanding of beam-induced transformations. Additionally, an electron beam simulation technique, Electron-Beam Simulator (E-BeamSim) is developed to observe the atomic movements and interactions resulting from electron beam irradiation. Using the MXene Ti<sub>3</sub>C<sub>2</sub>T<sub>x</sub>, the influence of temperature on nanopore fabrication is explored by tracking atomic transformations and find that at room temperature the electron beam irradiation induces random displacement and results in titanium pileups at the nanopore edge, which is confirmed by E-BeamSim. At elevated temperatures, after removal of the surface functional groups and with the increased mobility of atoms results in atomic transformations that lead to the selective removal of atoms layer by layer. This work can lead to the development of defect engineering techniques within functionalized MXene layers and other 2D materials. Nanopore ; Fabrication ; Materials science ; Nanotechnology ; Etching (microfabrication) ; MXenes ; Transmission electron microscopy ; Electron beam processing ; Scanning electron microscope ; Cathode ray ; Focused ion beam ; Scanning transmission electron microscopy ; Electron ; Layer (electronics) ; Ion ; Chemistry ; Composite material MXene and MAX Phase Materials ; Advanced biosensing and bioanalysis techniques ; Graphene research and applications