jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Vahid Jamebozorgi | Karsten Rasim | Christian Schröder
Source: Corrosion Science (article, 2024-06-19)
Field: Materials Science — Metals and Alloys

Computational chemistry analysis of passive layer formation and breakdown mechanisms in ferritic stainless steels Despite extensive research and proposed theories on formation and breakdown of passive layers, several questions remain unanswered. These include the reasons behind the bi-layer nature of the passive layer, the decrease in hydrogen and oxygen diffusivity upon entering the passive layer, and the influence of microstructure on passive layer formation and function in stainless steels. In this study, we employed ReaxFF molecular dynamics simulations to investigate passivation and depassivation of ferritic stainless steels in a polycrystalline structure. Through static and dynamic calculations, we elucidated the underlying mechanisms of passive layer formation, which were primarily governed by clustering. Our analysis also highlighted the significant role of hydrogen diffusion and its reaction with metallic compounds in the depassivation process. We have identified several physical phenomena involved in the processes of passivation and depassivation, which can provide explanations for the questions posed above. Passivation ; Materials science ; Corrosion ; Layer (electronics) ; Metallurgy ; Carbide ; ReaxFF ; Microstructure ; Hydrogen ; Crystallite ; Chemical physics ; Molecular dynamics ; Chemistry ; Composite material ; Computational chemistry Hydrogen embrittlement and corrosion behaviors in metals ; Fusion materials and technologies ; Ion-surface interactions and analysis
Authors: Mohd Shoeb | Fouzia Mashkoor | Mohmmad Naved Khan | Changyoon Jeong
Source: Molecules (article, 2024-10-31)
Field: Chemistry — Organic Chemistry

A Facile Synthesis of RGO-Ag2MoO4 Nanocomposites for Efficient Lead Removal from Aqueous Solution Efficiently treating wastewater, particularly the elimination of heavy metal ions from water systems, continues to be one of the most pressing and complex challenges in modern environmental management. In this work, reduced graphene oxide coupled silver molybdate binary nanocomposites (RGO-Ag<sub>2</sub>MoO<sub>4</sub> NCs) have been prepared via hydrothermal method. The crystalline nature and surface properties of the developed RGO-Ag<sub>2</sub>MoO<sub>4</sub> NCs were proved by XRD, FTIR, SEM, and EDS techniques. Adsorption experiments demonstrated that the nanocomposites (NCs) effectively removed Pb(II) ions within 120 min, achieving a maximum removal efficiency ranging from 94.96% to 86.37% for Pb(II) concentrations between 20 and 100 mg/L at pH 6. Kinetic studies showed that the adsorption process followed a pseudo-second order model. Isotherm analysis presented that the Langmuir model provided the greatest fit for the equilibrium data, with a monolayer adsorption capacity of 128.94 mg/g. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. The results of this study highlight RGO-Ag<sub>2</sub>MoO<sub>4</sub> NCs as a highly promising and eco-friendly material for the effective elimination of Pb(II) ions from wastewater. Their strong adsorption capacity, coupled with sustainable properties, makes them an efficient solution for addressing lead contamination, offering significant potential for practical applications in water treatment systems. Aqueous solution ; Lead (geology) ; Nanocomposite ; Chemistry ; Chemical engineering ; Nanotechnology ; Materials science ; Organic chemistry ; Engineering ; Geology Nanomaterials for catalytic reactions ; Gas Sensing Nanomaterials and Sensors ; Adsorption and biosorption for pollutant removal
Authors: Alexandra Jourdain | Christine Taviot‐Guého | Ulla Gro Nielsen | Vanessa Prévot | Claude Forano
Source: Dalton Transactions (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

In-depth characterization of phosphate intercalated Mg Al Layered double hydroxides and study of the PO<sub>4</sub> release properties Slow-release fertilizers (SRFs) form the core of innovative strategies in sustainable agriculture. Layered Double Hydroxides (LDH), known for their high capacity to sequester plant nutrients, especially phosphate, are emerging as promising candidates for SRF synthesis. The phosphate release properties of MgAl LDH (with a targeted Mg/Al ratio of 2.0) intercalated with HPO<sub>4</sub><sup>2-</sup> anions were assessed in various aqueous environments. A comprehensive analysis, including in-depth chemical and structural characterizations (ICP-OES, XRD, PDF, <sup>27</sup>Al NMR, <sup>31</sup>P NMR, FTIR, SEM) of the as-prepared phase unveiled a more intricate composition than anticipated for a pure or ideal Mg<sub>2</sub>Al-HPO<sub>4</sub> LDH, encompassing an excess of intercalated phosphate in conjunction with K<sup>+</sup>. Beyond the intercalated phosphate, solid state <sup>31</sup>P NMR speciation identified multiple H<sub>x</sub>PO<sub>4</sub><sup>(-3+<i>x</i>)</sup> environments, indicating a portion of the phosphate reacting with intralayer Mg<sup>2+</sup> to form K-struvite. Additionally, some phosphates were adsorbed onto the surface of amorphous aluminum hydroxide, a side phase formed during MgAl coprecipitation. The phosphate release demonstrated rapid kinetics, occurring within 6 days. Moreover, the released phosphate increased significantly when reducing the Solid/Liquid (S/L) ratio (58%) and further increasing in the presence of carbonate ions (90%). The released phosphate varied from 12% to 90% under different release conditions, transitioning from water to a 3.33 mM NaHCO<sub>3</sub> aqueous solution at a low S/L ratio (from 20 mg LDH per mL to 0.02 mg LDH per mL). The simultaneous release of K<sup>+</sup>, Mg<sup>2+</sup>, Al<sup>3+</sup> indicated the complete dissolution of the K-struvite and partial dissolution of phosphate intercalated MgAl LDH. These results enhanced our understanding of the mechanism governing phosphate release from MgAl LDH, paving the way for potential phosphate recovery by LDH or for the development of LDH-based SRFs. Layered double hydroxides ; Phosphate ; Characterization (materials science) ; Intercalation (chemistry) ; Chemistry ; Materials science ; Chemical engineering ; Inorganic chemistry ; Nuclear chemistry ; Nanotechnology ; Organic chemistry ; Hydroxide Layered Double Hydroxides Synthesis and Applications ; Magnesium Oxide Properties and Applications ; Microwave Dielectric Ceramics Synthesis
Authors: Safaa R. Fouda | Salah A. Hassan
Source: Scientific Reports (article, 2024-05-21)
Field: Chemistry — Organic Chemistry

Impact of LaZnFe2O4 supported NiWO4@D400-MMT@CMS/MMA nanocomposites as a catalytic system in remediation of dyes from wastewater Herein, a novel nanocomposite based on lanthanum zinc ferrite and nickel tungstate was created by incorporation between (MMT-jeffamine-400) nanoparticles (NPs), chloromethyl styrene as a binder and polymethyl methacrylate monomer using solution polymerization. The as-designed nanocomposites were employed to confiscate xylenol orange "X.O" as an acidic dye and rhodamine B "RhB" as "an amphoteric dye" from colored wastewater. The impact of several parameters such as solution pH, initial dye concentration, the effect of time, and the effect of temperature was explored. The consequences indicated that the pure organoclay had negligible adsorption while that composed of organoclay with PMMA@CMS-polymer incorporated with LaZnFe<sub>2</sub>O<sub>4</sub>@NiWO<sub>4</sub> particles detached more than 90% for xylenol orange (XO) and 93% for "rhodamine B" molecules. Electrostatic interactions are the predominant factor in the adsorption of cationic and amphoteric adsorbates, as proven by zeta-potential measurement. Additionally, the adsorbent may be regenerate and utilized up to five times with good adsorption capabilities by adding sodium hydroxide. As a result, the removal can be effectively accomplished using the nanocomposite as an adsorbent. The actual and theoretical adsorption capacity values for both dyes at all doses were closely matched, which supported the adsorption kinetics data that fit the pseudo-first order rate model well. The adsorption data's correlation values (0.995 for XO and 0.98 for RhB) indicated that both dyes' Langmuir adsorption would perform well. Furthermore, the adsorption of XO and RhB dyes on the adsorbent is confirmed to be a viable reaction by the negative values of ΔGo. The enhanced adsorbent material for the removal of amphoteric and anionic dyes from waste water is the synthesized LaZnFe2O4 supported NiWO4@D400-MMT@CMS/MMA nanocomposites, which exhibits a reusability affinity of up to five cycles. Environmental remediation ; Nanocomposite ; Wastewater ; Catalysis ; Environmental chemistry ; Chemical engineering ; Waste management ; Materials science ; Chemistry ; Environmental science ; Pulp and paper industry ; Organic chemistry ; Nanotechnology ; Contamination ; Environmental engineering ; Ecology ; Engineering Nanomaterials for catalytic reactions ; Advanced Photocatalysis Techniques ; Adsorption and biosorption for pollutant removal
Authors: Antoine Roueff | J. Pety | Maryvonne Gérin | Léontine Ségal | J. R. Goicoechea | H. S. Liszt | P. Gratier | Ivana Bešlić | Lucas Einig | Mathilde Gaudel | Jan H. Orkisz | Pierre Palud | Miriam G. Santa-Maria | Victor de Souza Magalhães | Antoine Zakardjian | Sébastien Bardeau | Émeric Bron | Pierre Chainais | Simon Coudé | Karine Demyk | Viviana Guzman Veloso | Annie Hughes | David Languignon | François Levrier | D. C. Lis | J. Le Bourlot | Franck Le Petit | N. Peretto | E. Roueff | A. Sievers | Pierre-Antoine Thouvenin
Source: Astronomy and Astrophysics (preprint, 2024-04-02)
Field: Chemistry — Spectroscopy

Bias versus variance when fitting multi-species molecular lines with a non-LTE radiative transfer model Context . Robust radiative transfer techniques are requisite for efficiently extracting the physical and chemical information from molecular rotational lines. Aims . We study several hypotheses that enable robust estimations of the column densities and physical conditions when fitting one or two transitions per molecular species. We study the extent to which simplifying assumptions aimed at reducing the complexity of the problem introduce estimation biases and how to detect them. Methods . We focus on the CO and HCO + isotopologues and analyze maps of a 50 square arcminutes field. We used the RADEX escape probability model to solve the statistical equilibrium equations and compute the emerging line profiles, assuming that all species coexist. Depending on the considered set of species, we also fixed the abundance ratio between some species and explored different values. We proposed a maximum likelihood estimator to infer the physical conditions and considered the effect of both the thermal noise and calibration uncertainty. We analyzed any potential biases induced by model misspecifications by comparing the results on the actual data for several sets of species and confirmed with Monte Carlo simulations. The variance of the estimations and the efficiency of the estimator were studied based on the Cramér-Rao lower bound. Results . Column densities can be estimated with 30% accuracy, while the best estimations of the volume density are found to be within a factor of two. Under the chosen model framework, the peak 12 CO (1 – 0) is useful for constraining the kinetic temperature. The thermal pressure is better and more robustly estimated than the volume density and kinetic temperature separately. Analyzing CO and HCO + isotopologues and fitting the full line profile are recommended practices with respect to detecting possible biases. Conclusions . Combining a non-local thermodynamic equilibrium model with a rigorous analysis of the accuracy allows us to obtain an efficient estimator and identify where the model is misspecified. We note that other combinations of molecular lines could be studied in the future. Isotopologue ; Estimator ; Radiative transfer ; Monte Carlo method ; Variance (accounting) ; Statistical physics ; Calibration ; Statistics ; Mathematics ; Physics ; Spectral line ; Optics Spectroscopy and Laser Applications ; Atmospheric and Environmental Gas Dynamics ; Atmospheric Ozone and Climate
Authors: Benjamin W. Caplins | Thomas J. Kolibaba | Uwe Arp | C. Cameron Miller | Yuqin Zong | Dianne L. Poster | Callie I. Higgins | Jason P. Killgore
Source: Additive manufacturing (article, 2024-04-01)
Field: Chemistry — Organic Chemistry

Influence of spectral bandwidth on the working curve in vat photopolymerization Materials science ; Photopolymer ; Bandwidth (computing) ; Optics ; Composite material ; Telecommunications ; Polymer ; Computer science ; Physics ; Polymerization Photopolymerization techniques and applications ; Additive Manufacturing and 3D Printing Technologies ; Interactive and Immersive Displays
Authors: P. Molinié
Source: Journal of Electrostatics (review, 2024-05-25)
Field: Materials Science — Materials Chemistry

How fast does a static charge decay? An updated review on a classical problem Charge (physics) ; Physics ; Quantum electrodynamics ; Theoretical physics ; Computer science ; Atomic physics ; Quantum mechanics High voltage insulation and dielectric phenomena ; Earthquake Detection and Analysis ; Mechanical and Optical Resonators
Authors: Sujeong Kim | Hyeongwoo Lee | Seonhye Eom | Gangseon Ji | Soo Ho Choi | Huitae Joo | Jin‐Hyuk Bae | Ki Kang Kim | Hyeong‐Ryeol Park | Kyoung‐Duck Park
Source: Science Advances (article, 2024-11-15)
Field: Materials Science — Materials Chemistry

Dynamical control of nanoscale electron density in atomically thin n-type semiconductors via nano-electric pulse generator Controlling electron density in two-dimensional semiconductors is crucial for both comprehensive understanding of fundamental material properties and their technological applications. However, conventional electrostatic doping methods exhibit limitations, particularly in addressing electric field-induced drift and subsequent diffusion of electrons, which restrict nanoscale doping. Here, we present a tip-induced nanospectroscopic electric pulse modulator to dynamically control nanoscale electron density, thereby facilitating precise measurement of nano-optoelectronic behaviors within a MoS<sub>2</sub> monolayer. The tip-induced electric pulse enables nanoscale modulation of electron distribution as a function of electric pulse width. We simultaneously investigate spatially altering photoluminescence quantum yield at the nanoscale region. We model the extent of electron depletion region, confirming a minimum doping region with a radius of ∼265 nanometers for a 30-nanosecond pulse width. Our approach paves the way for engineering local electron density and in situ nano-optical characterization in two-dimensional materials, enabling an in-depth understanding of doping-dependent nano-optoelectronic phenomena. Materials science ; Electric field ; Semiconductor ; Doping ; Nanoscopic scale ; Electron ; Optoelectronics ; Electron density ; Nanotechnology ; Nano- ; Physics 2D Materials and Applications ; Nanowire Synthesis and Applications ; Semiconductor Quantum Structures and Devices
Authors: Khasim Saheb Bayikadi | Safdar Imam | Wei-Shen Tee | S. Kavirajan | Chun-Lin Chang | Amr Sabbah | Fang‐Yu Fu | Ting‐Ran Liu | Ching‐Yu Chiang | D. K. Shukla | Chien‐Ting Wu | Li–Chyong Chen | M. Y. Chou | Kuei‐Hsien Chen | R. Sankar
Source: Journal of Materials Chemistry A (article, 2024-01-01)
Field: Materials Science — Materials Chemistry

Ultra-low lattice thermal conductivity driven high thermoelectric figure of merit in Sb/W co-doped GeTe Phonon scattering processes to κ lat of Ge 0.85 Sb 0.1 W 0.05 Te: Umklapp, boundary, point-defect, stacking faults, resonant scattering, nanoprecipitates &amp; microstructural effects. (b) κ lat reduction (inset: ZT enhancement). Figure of merit ; Materials science ; Thermoelectric effect ; Thermal conductivity ; Doping ; Condensed matter physics ; Thermoelectric materials ; Lattice (music) ; Optoelectronics ; Composite material ; Physics ; Thermodynamics Advanced Thermoelectric Materials and Devices ; Phase-change materials and chalcogenides ; Chalcogenide Semiconductor Thin Films
Authors: Ama tul Zahra | Aamir Shahzad | Alina Manzoor | Jamoliddin Razzokov | Qurat ul Ain Asif | Kun Luo | Guogang Ren
Source: PLoS ONE (article, 2024-02-09)
Field: Materials Science — Materials Chemistry

Structural and thermal analyses in semiconducting and metallic zigzag single-walled carbon nanotubes using molecular dynamics simulations Equilibrium molecular dynamics (EMD) simulations have been performed to investigate the structural analysis and thermal conductivity (λ) of semiconducting (8,0) and metallic (12,0) zigzag single-walled carbon nanotubes (SWCNTs) for varying ±γ(%) strains. For the first time, the present outcomes provide valuable insights into the relationship between the structural properties of zigzag SWCNTs and corresponding thermal behavior, which is essential for the development of high-performance nanocomposites. The radial distribution function (RDF) has been employed to assess the buckling and deformation understandings of the (8,0) and (12,0) SWCNTs for a wide range of temperature T(K) and varying ±γ(%) strains. The visualization of SWCNTs shows that the earlier buckling and deformation processes are observed for semiconducting SWCNTs as compared to metallic SWCNTs for high T(K) and it also evident through an abrupt increase in RDF peaks. The RDF and visualization analyses demonstrate that the (8,0) SWCNTs can more tunable under compressive than tensile strains, however, the (12,0) zigzag SWCNTs indicate an opposite trend and may tolerate more tensile than compressive strains. Investigations show that the tunable domain of ±γ(%) strains decreases from (-10%≤ γ ≤+19%) to (-5%≤ γ ≤+10%) for (8,0) SWCNTs and the buckling process shifts to lower ±γ(%) for (12,0) SWCNTs with increasing T(K). For intermediate-high T(K), the λ(T) of (12,0) SWCNTs is high but the (8,0) SWCNTs show certainly high λ(T) for low T(K). The present λ(T, ±γ) data are in reasonable agreement with parts of previous NEMD, GK-HNEMD data and experimental investigations with simulation results generally under predicting the λ(T, ±γ) by the ∼1% to ∼20%, regardless of the ±γ(%) strains, depending on T(K). Our simulation data significantly expand the strain range to -10% ≤ γ ≤ +19% for both zigzag SWCNTs, depending on temperature T(K). This extension of the range aims to establish a tunable regime and delve into the intrinsic characteristics of zigzag SWCNTs, building upon previous work. Zigzag ; Carbon nanotube ; Materials science ; Molecular dynamics ; Ultimate tensile strength ; Buckling ; Metal ; Nanocomposite ; Deformation (meteorology) ; Thermal conductivity ; Nanotechnology ; Composite material ; Computational chemistry ; Chemistry ; Metallurgy ; Geometry Carbon Nanotubes in Composites ; Thermal properties of materials ; Boron and Carbon Nanomaterials Research
Authors: Pratap S. Dabhade | Manjushri P. Dabhade | Lala S. Rathod | Sachin A. Dhawale | Shweta A. More | Somdatta Y. Chaudhari | Santosh N. Mokale
Source: Chemistry & Biodiversity (article, 2024-05-06)
Field: Chemistry — Organic Chemistry

Novel Pyrazole‐Chalcone Hybrids: Synthesis and Computational Insights Against Breast Cancer More women die of breast cancer than of any other malignancy. The resistance and toxicity of traditional hormone therapy created an urgent need for potential molecules for treating breast cancer effectively. Novel biphenyl-substituted pyrazole chalcones linked to a pyrrolidine ring were designed by using a hybridization approach. The hybrids were assessed against MCF-7 and MDA-MB-231 cells by NRU assay. Among them, 8 k, 8 d, 8 m, 8 h, and 8 f showed significantly potent IC<sub>50</sub> values: 0.17, 5.48, 8.13, 20.51, and 23.61 μM) respectively, on MCF-7 cells compared to the positive control Raloxifene and Tamoxifen. Furthermore, most active compound 8 k [3-(3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)-1-(2-(2-(pyrrolidin-1-yl)-ethoxy)-phenyl)-chalcone] showed cell death induced through apoptosis, cell cycle arrest at the G2/M phase, and demonstrated decrease of ER-α protein in western blotting study. Docking studies of 8 k and 8 d established adequate interactions with estrogen receptor-α as required for SERM binding. The active hybrids exhibited good pharmacokinetic properties for oral bioavailability and drug-likeness. Whereas, RMSD, RMSF, and Rg values from Molecular dynamics studies stipulated stability of the complex formed between compound 8 k and receptor. All of these findings strongly indicate the antiproliferative potential of pyrazole-chalcone hybrids for the treatment of breast cancer. Chalcone ; Pyrazole ; Chemistry ; Breast cancer ; Hybrid ; Cancer ; Cancer research ; Malignancy ; Stereochemistry ; Pharmacology ; Internal medicine ; Combinatorial chemistry ; Medicine ; Biology ; Botany Synthesis and biological activity ; Synthesis and Biological Evaluation ; Cancer therapeutics and mechanisms
Authors: Wenlong Xia | Hengzhi Liu | Yufang Chen | Xingqiao Wu | Yuchao Du | Keyang Fu | Manfang Chen | Xiukang Yang | Xianyou Wang | Hongbo Shu
Source: Small (article, 2024-12-31)
Field: Materials Science — Materials Chemistry

Linking D‐Band Center Modulation with Rapid Reversible Sulfur Conversion Kinetics via Structural Engineering of VS₂ The rapid catalytic conversion toward polysulfides is considered to be an advantageous approach to boost the reaction kinetics and inhibit the shuttle effect in lithium-sulfur (Li─S) batteries. However, the prediction of high catalytic activity Li─S catalysts has become challenging given the carelessness in the relationship between important electronic characteristics of catalysts and catalytic activity. Herein, the relationships between the D-band regulation of catalysts with reaction kinetics toward polysulfides are described. Through the combination of experimental and theoretical analysis, the opportune upward shift of the D-band center results in a favorable interaction with polysulfides, controlling the adsorption behavior of polysulfides. In addition, the electron regulation achieved by moderately moving up the D-band center further reduces the reaction energy barrier through hybridization with polysulfides. Based on this, a composite catalyst Mo doped VS<sub>2</sub>/rGO as a host material is proposed, which provides impressive long-term cycling stability and superior rate performance. This fundamental knowledge of the inherent connection between the D-band center of the catalyst and the reaction Kinetics of polysulfides offers a rationale for the development of the Li─S catalyst and the modification of its activity. Kinetics ; Modulation (music) ; Center (category theory) ; Materials science ; Sulfur ; Chemical engineering ; Nanotechnology ; Chemistry ; Crystallography ; Physics ; Engineering ; Metallurgy Solid-state spectroscopy and crystallography ; Thermal and Kinetic Analysis ; Thermal Expansion and Ionic Conductivity