jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Meng Li | Tao Cheng | Gongze Liu | He Huang | Keqiao Li | Li Yang | Jia‐Yue Yang | Baoling Huang
Source: arXiv (Cornell University) (preprint, 2023-12-15)
Field: Materials Science — Materials Chemistry

Infrared anomalies in ultrathin Ti3C2Tx MXene films Visible transparent but infrared reflective materials are ideal candidates for both transparent conductive films and low-emissivity glass, which are highly desired in a broad variety of areas such as touchscreens and displays, photovoltaics, smart windows, and antistatic coatings. Ultrathin Ti3C2Tx MXene films are emerging as promising low-emissivity transparent candidates. However, the fundamental IR properties of Ti3C2Tx has not been revealed experimentally due to daunting challenges in the preparation of continuous, large-area, and ultrathin films of optical quality on flat substrates. Herein, we proposed a tape-free transfer method that can help prepare centimeter-size and ultrathin (down to 8 nm) Ti3C2Tx films on diverse optical substrates. Benefitting from this method, the refractive index and permittivity for Ti3C2Tx were successfully measured. Ti3C2Tx films exhibit large in-plane permittivity in the IR region, yielding maximum IR reflectance of 88% for bulk films. Interestingly, three anomalies were found in ultrathin Ti3C2Tx films: strong dispersion in the permittivity, interlayer space-dependent optical properties, and abnormally high IR absorption for a 15-nm-thick film. These anomalies are important guidelines in the design of Ti3C2Tx-based low-emissivity transparent films and other related devices, and may inspire other intriguing applications such as ultrathin IR absorption coatings and tunable IR optical devices. Materials science ; Permittivity ; Emissivity ; Optoelectronics ; Infrared ; Absorption (acoustics) ; Refractive index ; Photovoltaics ; Low emissivity ; Optics ; Nanotechnology ; Composite material ; Dielectric ; Layer (electronics) ; Photovoltaic system MXene and MAX Phase Materials ; Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies
Authors: Taesu Choi | Dooyoul Lee
Source: Materials (article, 2023-07-28)
Field: Materials Science — Materials Chemistry

Physics-Informed, Data-Driven Model for Atmospheric Corrosion of Carbon Steel Using Bayesian Network Atmospheric corrosion is a significant challenge faced by the aviation industry as it considerably affects the structural integrity of an aircraft operated for long periods. Therefore, an appropriate corrosion deterioration model is required to predict corrosion problems. However, practical application of the deterioration model is challenging owing to the limited data available for the parameter estimation. Thus, a high uncertainty in prediction is unavoidable. To address these challenges, a method of integrating a physics-based model and the monitoring data on a Bayesian network (BN) is presented herein. Atmospheric corrosion is modeled using the simulation method, and a BN is constructed using GeNie. Moreover, model calibration is performed using the monitoring data collected from aircraft parking areas. The calibration approach is an improvement over existing models as it incorporates actual environmental data, making it more accurate and applicable to real-world scenarios. In conclusion, our research emphasizes the importance of precise corrosion models for predicting and managing atmospheric corrosion on carbon steel. The study results open new avenues for future research, such as the incorporation of additional data sources to further improve the accuracy of corrosion models. Corrosion ; Calibration ; Experimental data ; Bayesian network ; Aviation ; Bayesian probability ; Carbon steel ; Computer science ; Environmental science ; Data mining ; Engineering ; Materials science ; Machine learning ; Aerospace engineering ; Artificial intelligence ; Metallurgy ; Statistics ; Mathematics Corrosion Behavior and Inhibition ; Hydrogen embrittlement and corrosion behaviors in metals ; Non-Destructive Testing Techniques
Authors: O.B. Ovonramwen | E.I. Amoren
Source: Dutse Journal of Pure and Applied Sciences (article, 2023-07-16)
Field: Materials Science — Biomaterials

Extraction of Chitosan from &lt;i&gt;L. squarrosulus&lt;/i&gt; (Mushroom) and &lt;i&gt;C. africana&lt;/i&gt; (Shrimp) Based and Production of Film Polymer The deacetylated form of chitin presents enormous areas of application. The research work was aimed at the production of polymer film by the extraction of chitosan from Lentinus squarrosulus (mushroom) and Caridina africana (shrimp) using a chemical process involving deproteinisation, demineralisation, and deacetylation. The two samples were thoroughly washed with distilled water to remove impurities, then dried at room temperature for three days. The mushroom was grounded to powder, deproteinised at varying concentrations (1, 2, 3, and 4 M) and temperatures (60, 80, and 100 °C). The emanating products were now demineralised and deacetylated at 3 M and 60 °C. Biuret test analysis was carried out on 3 M, 60 °C and 4 M, 100 °C of L. squarrosulus chitosan and C. africana with the later showing a clearer positive result for the application. The physicochemical and mechanical properties of chitosan composite films of C. africana and gelatinous composition (CS30: G70, CS50: G50, and CS70: G30) plasticised with glycerol were studied. The chitosan composite films, L. squarrosulus (3 M, 60 °C), and C. africana were characterised by FT-IR. The FTIR spectra showed the functional groups associated with the various bands, intensities, and stretching established that the samples were chitosan. The results of the flexibility and refractive index analysis indicated that the higher chitosan films were more flexible and refractive, finding a much greater application in the manufacture of lenses of higher magnification. The FTIR spectra of the compact films of the homogeneous structure showed that there was a reaction in C. africana chitosan. The SEM analysis of chitosan in C. africana showed morphological differences of ×300, ×500, ×1000, and ×1500. Chitosan ; Mushroom ; Nuclear chemistry ; Shrimp ; Extraction (chemistry) ; Fourier transform infrared spectroscopy ; Chemistry ; Chitin ; Polymer ; Materials science ; Chemical engineering ; Food science ; Chromatography ; Organic chemistry ; Biology Nanocomposite Films for Food Packaging
Authors: Norie Momiyama | Tatsuaki Hori | Shuya Kakinuma | Naoya Ohtsuka | Takeshi Fujinami | Toshiyasu Suzuki
Source: Synlett (article, 2023-06-27)
Field: Chemistry — Organic Chemistry

Synthesis of Halogen-Bond-Donor-Site-Introduced Functional Monomers through Wittig Reaction of Perfluorohalogenated Benzaldehydes: Toward Digitalization as Reliable Strategy in Small-Molecule Synthesis Abstract The Wittig reaction of perfluoromonohalobenzaldehydes was systematically studied to synthesize 2,3,5,6-tetrafluoro-4-halostyrene (TFXSs) as functional monomers bearing halogen-bond donor sites. The reaction proceeded efficiently in tetrahydrofuran using 1,1,3,3-tetramethylguanidine as an organic base. Correlation analysis quantitatively identified three key factors required to obtain TFXSs in reasonable yields. The present approach not only contributes to the study of halogen-bond-based functional molecules, but also presents digitalization as a potential strategy in small-molecule synthesis. Chemistry ; Wittig reaction ; Halogen ; Tetrahydrofuran ; Halogen bond ; Monomer ; Molecule ; Combinatorial chemistry ; Base (topology) ; Organic chemistry ; Polymer Synthesis and Catalytic Reactions ; Organic Chemistry Cycloaddition Reactions ; Fluorine in Organic Chemistry
Authors: Ismael Krüger Pescke | Lívia de Oliveira Rozino | Karoline Silva Zenato | Tatiane Rocha Cardozo | Wladimir Hernández Flores | Vera Maria Ferrão Vargas
Source: Journal of Applied Toxicology (article, 2023-10-12)
Field: Materials Science — Materials Chemistry

Lowering the pH leads to the disaggregation of NiO and ZnO nanoparticles and modifies the mutagenic response In a changing environmental scenario, acid rain can have a significant impact on aquatic ecosystems. Acidification is known to produce corrosion in metals, hence increasing their harmful effects on the environment, organisms and human health. The prevalent use of metallic nanoparticles (NPs) in everyday products raises concerns regarding exposure and nanotoxicity even in these acidified conditions. We thus report on the cytotoxic and genotoxic potential of nickel oxide (NiO-NP) and zinc oxide (ZnO-NP) NPs when suspended in aqueous media in light of pH variations (7.5 and 5). A modified microsuspension method of the Salmonella/microsome assay was adopted, and strains (TA97a, TA98, TA100, TA102) were exposed to NPs (10-1280 μg/plate) with and without a metabolization fraction. The acidic condition favored disaggregation and caused a decrease in NPs size. Mutagenicity was observed in all samples and different strains, with greater DNA base pair substitution damage (TA100 and TA102), but extrinsic conditions (pH) suggest different action mechanisms of NiO-NP and ZnO-NP on genetic content. Mutagenic activity was found to increase upon metabolic activation (TA98, TA100, and TA102) demonstrating the bioactivity of NiO-NP and ZnO-NP in relation to metabolites generated by the mammalian p450 system in vitro. Modifications in the Salmonella assay methodology increased cell exposure time. The observed responses recommend this modified assay as one of the methodologies of choice for nanoecotoxicological evaluation. These findings emphasize the significance of incorporating the environmental context when evaluating the toxicity of metal-based NPs. Chemistry ; Nanotoxicology ; Context (archaeology) ; Environmental chemistry ; Toxicity ; DNA damage ; Non-blocking I/O ; Metal ; Nanoparticle ; Salmonella ; Cytotoxicity ; Biophysics ; Biochemistry ; DNA ; In vitro ; Nanotechnology ; Bacteria ; Organic chemistry ; Biology ; Genetics Nanoparticles: synthesis and applications ; Microplastics and Plastic Pollution ; Carcinogens and Genotoxicity Assessment
Authors: Maxim V. Zdorovets | G.Zh. Moldabayeva | Inesh Z. Zhumatayeva | Daryn B. Borgekov | R. I. Shakirzyanov | Аrtem L. Kozlovskiy
Source: ChemEngineering (article, 2023-11-01)
Field: Materials Science — Materials Chemistry

Study of the Effect of Adding Nb2O5 on Calcium Titanate-Based Ferroelectric Ceramics This paper considers the effect of adding niobium oxide (Nb2O5) to ferroelectric ceramics based on calcium titanate (CaTiO3), and establishes a connection between the observed alterations in strength and dielectric properties and the variation in the Nb2O5 dopant concentration in the ceramics’ composition. The method of mechanochemical solid-phase synthesis was used as the main method for obtaining the ceramics, followed by thermal sintering under specified conditions in order to form a stable phase composition of the ceramics, and to initialize phase transformations in the composition. Based on the assessment of the phase composition of the resulting ceramics, it was determined that a growth in the Nb2O5 dopant concentration beyond 0.10 mol results in the formation of an orthorhombic-phase CaNb2O4 of the Pbcm(57) spatial system, the weight contribution of which grows. A growth in the Nb2O5 additive concentration results in the formation of two-phase ceramics, the formation of which allows for an enhancement in the mechanical strength of ceramics and resistance to external influences. During the study of the dependence of the strength properties on the dopant concentration alteration, a three-stage change in hardness and crack resistance was established, regarding both structural ordering and phase transformations. The measurement of dielectric characteristics showed the direct dependence of dielectric losses and the dielectric constant on the phase composition of ceramics. Materials science ; Dopant ; Dielectric ; Ceramic ; Calcium titanate ; Orthorhombic crystal system ; Phase (matter) ; Ferroelectricity ; Sintering ; Mineralogy ; Niobium ; Composite material ; Analytical Chemistry (journal) ; Doping ; Metallurgy ; Crystal structure ; Crystallography ; Chemistry ; Optoelectronics ; Organic chemistry Ferroelectric and Piezoelectric Materials ; Material Science and Thermodynamics ; Advanced Energy Technologies and Civil Engineering Innovations
Authors: Kun Luan | Ming Chen | Xiaomeng Fang | Jianjun Liu
Source: Ceramics (article, 2023-10-05)
Field: Materials Science — Materials Chemistry

Frequency Characteristics of High Strain Rate Compressions of Cf-MWCNTs/SiC Composites The incorporation of ductile reinforcements into ceramics helps restrain crack deflection, which can enhance ceramics’ toughness and overcome the matrix’s brittleness. In this paper, we produced a ceramic composite reinforced by carbon fibers coated by multi-wall carbon nanotubes (shortened by Cf-MWCNT/SiC composites) for enhanced impact resistance at a high strain rate that commonly occurs in composite materials used in astronautics, marine, and other engineering fields. The fabrication process involves growing multi-wall carbon nanotubes (MWCNTs) on a carbon fiber woven fabric (Cf) to create the fibril/fabric hybrid reinforcement. It is then impregnated by polymer solution (precursor of the ceramics), forming composites after the pyrolysis process, known as the liquid polymer infiltration and pyrolysis (PIP) technique. To assess the impact resistance of the Cf-MWCNT/SiC under high-strain rate compressions, the split Hopkinson pressure bar (SHPB) technique is employed. Since the failure behavior of the Cf-MWCNT/SiC composites in the absence of the ductile phase is not well understood, the study employs the Hilbert–Huang transform (HHT) to analyze the stress–time curves obtained from the SHPB experiments. By applying the HHT, we obtained the frequency–time spectrum and the marginal Hilbert spectrum of the stress signals. These analyses reveal the frequency characteristics of the Cf-MWCNT/SiC composite and provide insights into the relationship between transformed signal frequency and fracture behavior. By understanding the dynamic fracture behavior and frequency response of the Cf-MWCNT/SiC, it becomes possible to enhance its impact resistance and tailor its performance for specific protective requirements. Therefore, the findings of this study can guide the future design and optimization of Cf-MWCNT/SiC structures for various protective applications, such as body armor, civil structures, and protections for vehicles and aircraft. Materials science ; Composite material ; Split-Hopkinson pressure bar ; Carbon nanotube ; Ceramic ; Composite number ; Ceramic matrix composite ; Fracture toughness ; Toughness ; Brittleness ; Strain rate High-Velocity Impact and Material Behavior ; Advanced ceramic materials synthesis
Authors: Raashiq Ishraaq | Tanmay Sarkar Akash | Arka Bera | Siddhartha Das
Source: ChemRxiv (preprint, 2023-11-29)
Field: Materials Science — Surfaces, Coatings and Films

Hydrophilic and Apolar Hydration in Densely Grafted Cationic Brushes and Counterions with Large Mobilities We employ all-atom MD simulation framework to unravel water microstructure and ion properties for cationic PMETAC or [Poly(2-(methacryloyloxy)ethyl trimethylammonium chloride] brushes with chloride ions as counterions. First, we identify locally separate water regions (with different structural properties) each around the {N(CH3)3}+ and the C=O functional groups of the PMETAC chain and one around the Cl- ion. These water regions or domains, which are effectively the first hydration shells around the respective moieties, overlap and the extent of the overlap depends on the nature of the species triggering it. Second, despite the overlap, the water molecules in these domains demonstrate disparate properties dictated by the properties of the atoms/groups around which they are located. For example, the N atom is present as the {N(CH3)3}+ group in the PMETAC chain and the presence of the methyl groups make the {N(CH3)3}+ group trigger apolar hydration as evidenced by the corresponding orientation of the dipole of the water molecules within the water domain formed around the {N(CH3)3}+ moiety. Further, we report that the water molecules constituting the apolar hydration layer around the N(CH3)3}+ group have enhanced tetrahedrality as compared to the water molecules constituting the hydration layer around the C=O group and the Cl- counterion. Our simulations also identify that there is an intervening water layer between the Cl- ion and {N(CH3)3}+ group: the stability of this water layer prevents the Cl- ion from coming very close to the {N(CH3)3}+ group, despite the strong electrostatic attraction between these oppositely charged species. As a consequence, there is a significantly large mobility of the Cl- ions inside the PMETAC brush layer. Furthermore, the C=O group of the PE chain, due to the partial negative charge on the oxygen atom and the specific structure of the system (namely the fact that the C=O group is a part of the PMETAC chains in brush-like configuration and are significantly away from other influencing moieties), demonstrates strongly hydrophilic behavior and enforces a specific dipole response of water molecules analogous to that experienced by water around anionic species of high charge density. In summary, our findings confirm that PMETAC brushes undergo hydrophilic hydration at one site, apolar hydration at another site, and ensures large mobility of the supported Cl- counterions. Counterion ; Cationic polymerization ; Chemistry ; Molecule ; Chloride ; Moiety ; Ion ; Group (periodic table) ; Crystallography ; Polymer chemistry ; Stereochemistry ; Organic chemistry Polymer Surface Interaction Studies ; Advanced Polymer Synthesis and Characterization ; Luminescence and Fluorescent Materials
Authors: Xinming Li
Source: Journal of Computer and Communications (article, 2023-01-01)
Field: Chemistry — Spectroscopy

Classification of B and Y Ions in Peptide MS/MS Spectra Based on Machine Learning In proteomics, b and y ions serve as the backbone ions for peptide sequencing in tandem mass spectrometry. Leveraging the existing ion recognition and separation methods, this article proposes a novel ion classification approach that combines machine learning with graph theory. By incorporating graph features, the method achieves higher accuracy and efficiency in ion type recognition, with the graph features playing a critical role in the classification process. Specifically, the method achieves a recall rate of nearly 90% for b and y ions, demonstrating its effectiveness in pre-processing de novo sequencing and improving its accuracy. The proposed method represents advancement in ion classification and has the potential to improve the accuracy and efficiency of de novo sequencing. Ion ; Computer science ; Graph ; Tandem mass spectrometry ; Mass spectrometry ; Artificial intelligence ; Recall ; Peptide ; Pattern recognition (psychology) ; Chemistry ; Chromatography ; Theoretical computer science ; Biochemistry ; Psychology Advanced Proteomics Techniques and Applications ; Mass Spectrometry Techniques and Applications ; Metabolomics and Mass Spectrometry Studies
Authors: Xi Yang | Zhirong Zhang | Shuang Yang | Pengshuai Sun | Bian Wu | Hua Xia | Runqing Yu
Source: Sensors (article, 2023-04-11)
Field: Chemistry — Spectroscopy

Development of a Rapid Measurement Method for Analysis of the NOx Conversion Process Based on Quantum Cascade Laser Absorption Spectroscopy In this study, a method for double-beam quantum cascade laser absorption spectroscopy (DB-QCLAS) was developed. Two mid-infrared distributed feedback quantum cascade laser beams were coupled in an optical cavity for the monitoring of NO and NO<sub>2</sub> (NO at 5.26 μm; NO<sub>2</sub> at 6.13 μm). Appropriate lines in the absorption spectra were selected, and the influence of common gases in the atmosphere, such as H<sub>2</sub>O and CO<sub>2</sub>, was avoided. By analyzing the spectral lines under different pressure conditions, the appropriate measurement pressure of 111 mbar was selected. Under this pressure, the interference between adjacent spectral lines could be effectively distinguished. The experimental results show that the standard deviations for NO and NO<sub>2</sub> were 1.57 ppm and 2.67 ppm, respectively. Moreover, in order to improve the feasibility of this technology for detecting chemical reactions between NO and O<sub>2</sub>, the standard gases of NO and O<sub>2</sub> were used to fill the cavity. A chemical reaction instantaneously began, and the concentrations of the two gases were immediately changed. Through this experiment, we hope to develop new ideas for the accurate and rapid analysis of the process of NOx conversion and to lay a foundation for a deeper understanding of the chemical changes in atmospheric environments. Quantum cascade laser ; NOx ; Absorption spectroscopy ; Cascade ; Spectroscopy ; Atmospheric pressure ; Absorption (acoustics) ; Laser ; Infrared spectroscopy ; Chemistry ; Spectral line ; Analytical Chemistry (journal) ; Interference (communication) ; Materials science ; Optics ; Physics ; Combustion ; Meteorology ; Physical chemistry ; Telecommunications ; Environmental chemistry Spectroscopy and Laser Applications ; Atmospheric and Environmental Gas Dynamics ; Atmospheric Ozone and Climate
Authors: L. Hehn | Peter Deglmann | Michael Kühn
Source: ChemRxiv (preprint, 2023-12-07)
Field: Chemistry — Inorganic Chemistry

Chelate Complexes of 3d Transition Metal Ions – A Challenge for Electronic-Structure Methods? Different electronic-structure methods were assessed for their ability to predict two important properties of the industrially relevant chelating agent nitrilotriacetic acid (NTA): its selectivity with respect to six different first-row transition metal ions and the spin-state energetics of its complex with Fe(III). The investigated methods encompassed density functional theory (DFT), the random phase approximation (RPA), coupled cluster (CC) theory, the auxiliary-field quantum Monte-Carlo (AFQMC) method, as well as the complete active space self-consistent field (CASSCF) method and the respective on-top methods second-order N-electron valence state perturbation theory (NEVPT2) and multiconfiguration pair-density functional theory (MC-PDFT). Different strategies for selecting active spaces were explored and the density matrix renormalization group (DMRG) approach was used to solve the largest active spaces. Despite somewhat ambiguous multi-reference diagnostics, most methods gave relatively good agreement with experimental data for the chemical reactions connected to the selectivity, which only involved transition-metal complexes in their high-spin state. CC methods yielded the highest accuracy followed by range-separated DFT and AFQMC. We discussed in detail that even higher accuracies can be obtained with NEVPT2, under the prerequisite that consistent active spaces along the entire chemical reaction can be selected, which was not the case for reactions involving Fe(III). A bigger challenge for electronic-structure methods was the prediction of the spin-state energetics, which additionally involved lower spin states that exhibited larger multi-reference diagnostics. Conceptually different, typically accurate methods ranging from CC theory via DMRG-NEVPT2 in combination with large active spaces to AFQMC agreed well that the high-spin state is energetically significantly favored over the other spin states. This was in contrast to most DFT functionals and RPA which yielded a smaller stabilization and some common DFT functionals and MC-PDFT even predicting the low-spin state to be energetically most favorable. Complete active space ; Nitrilotriacetic acid ; Density functional theory ; Chemistry ; Density matrix renormalization group ; Coupled cluster ; Valence (chemistry) ; Spin states ; Electronic structure ; Perturbation theory (quantum mechanics) ; Computational chemistry ; Quantum Monte Carlo ; Atomic physics ; Molecule ; Monte Carlo method ; Chelation ; Quantum mechanics ; Physics ; Renormalization group ; Mathematics ; Inorganic chemistry Radioactive element chemistry and processing ; Electrochemical Analysis and Applications ; Metal complexes synthesis and properties