jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Thomas Harter | Alexander Wagner | A. Wolfbauer | Ingo Bernt | Andreas Mautner | Monika Kriechbaum | Andreas Nevosad | Ulrich Hirn
Source: Cellulose (article, 2023-12-30)
Field: Materials Science — Polymers and Plastics

The influence of viscose fibre properties on the absorbency of feminine hygiene tampons: the pivotal role of cross-sectional geometry Abstract Feminine hygiene products, used by millions of women worldwide on a daily basis, come in various forms. Among them, tampons are a prominent type that aims to absorb menstrual blood directly in the vagina. However, the underlying mechanisms governing liquid absorption in tampons have received limited research attention and remain poorly understood. This study aims to investigate these mechanisms by examining the two main types of viscose fibres used in tampons and their effects when employed in tampon production. The sole distinction between the fibre types lies in their geometric shape—round or trilobal—while all other fibre parameters remain constant. To explore these mechanisms, tampon proxies made from these fibres were created and subjected to tests measuring liquid absorption. In addition, a novel method employing infrared thermography was utilized to infer the stored energy within the compressed tampon. Furthermore, individual fibres were characterised for chemical composition, surface properties, fine structure, liquid interaction, mechanical parameters, and friction behaviour. The results revealed that trilobal fibres exhibited higher tampon absorbency compared to their round counterparts, despite sharing similar chemical composition and comparable mechanical characteristics. This disparity can be attributed to the greater specific surface area of trilobal fibres, leading to enhanced liquid uptake through fibre swelling. However, single fibre swelling only accounted for a minor fraction of the total liquid absorbency of a tampon. The most influential fibre parameter was the geometric shape, as trilobal fibres facilitated the construction and maintenance of a bulkier network with increased available volume for liquid absorption. Graphic abstract Viscose ; Materials science ; Composite material ; Absorption (acoustics) ; Absorption of water ; Swelling Textile materials and evaluations ; Natural Fiber Reinforced Composites ; Electrospun Nanofibers in Biomedical Applications
Authors: Hongxing Zheng | Haiyang Hu | Thomas Weber | Juan Wang | Nan Lin | Bingsuo Zou | Stefan A. Maier | Andreas Tittl
Source: arXiv (Cornell University) (preprint, 2023-11-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

All-Dielectric Structural Coloration Empowered by Bound States in the Continuum The technological requirements of low-power and high-fidelity color displays have been instrumental in driving research into advanced coloration technologies. At the forefront of these developments is the implementation of dye-free coloration techniques, which overcome previous constraints related to insufficient resolution and color fading. In this context, resonant dielectric nanostructures have emerged as a promising paradigm, showing great potential for high efficiency, remarkably high color saturation, wide gamut palette, and realistic image reproduction. However, they still face limitations related to color accuracy, purity, and simultaneous brightness tunability. Here, we demonstrate an all-dielectric metasurface empowered by photonic bound states in the continuum (BICs), which supports sharp resonances throughout the visible spectral range, ideally suited for producing a wide range of structural colors. The metasurface design consists of titanium dioxide (TiO2) ellipses with carefully controlled sizes and geometrical asymmetry, allowing versatile and on-demand variation of the brightness and hue of the output colors, respectively. Gamut ; Structural coloration ; Brightness ; Dielectric ; Optics ; Hue ; Photonics ; Materials science ; RGB color model ; Palette (painting) ; Fidelity ; Optoelectronics ; Computer science ; Photonic crystal ; Artificial intelligence ; Physics ; Telecommunications Metamaterials and Metasurfaces Applications ; Polydiacetylene-based materials and applications ; Advanced Antenna and Metasurface Technologies
Authors: Emmanuel Picheau | Ferdinand Hof | Sara Amar | Alain Derré | Alain Pénicaud
Source: Angewandte Chemie International Edition (article, 2023-04-06)
Field: Materials Science — Materials Chemistry

Burning Graphite Faster than Carbon Black: A Case of Diffusion Control Abstract External diffusion may be exploited as a tool to purify materials in a way thought to be inaccessible from a chemical reactivity point of view. A mixture of two carbonaceous materials, graphite and carbon black, are thermally oxidized in either i) outside total diffusion‐limited regime or ii) total diffusion‐limited regime. Depending on the treatment applied it is possible to purify either graphite, a trivial task, or carbon black, a task thought impossible. Introducing geometrical selectivity, controlled total diffusion‐limited chemistry exceeds by far the field of carbon materials and can be used as an engineering tool for many materials purification, original synthesis, or to introduce asymmetry in a system. Several examples for direct applications of the findings are mentioned. Graphite ; Carbon black ; Diffusion ; Carbon fibers ; Reactivity (psychology) ; Nanotechnology ; Chemistry ; Chemical engineering ; Materials science ; Organic chemistry ; Physics ; Thermodynamics ; Composite material ; Engineering ; Natural rubber Carbon Nanotubes in Composites ; Zeolite Catalysis and Synthesis ; Graphene research and applications
Authors: Volodymyr V. Semeno | Vadym O. Vasylchenko | Ihor M. Fesun | Liudmyla Yu. Ruzhylo | Mykhailo O. Kipriianov | Kostiantyn P. Melnykov | Artem Skreminskyi | Rustam T. Iminov | Bohdan V. Vashchenko | Oleksandr O. Grygorenko
Source: ChemRxiv (preprint, 2023-11-14)
Field: Chemistry — Organic Chemistry

Bicyclo[m.n.k]alkane Building Blocks as Promising Benzene and Cycloalkane Isosteres: Multigram Synthesis, Physicochemical and Structural Characterization Electrophilic double bond functionalization – intramolecular enolate alkylation sequence was used to obtain a series of bridged and fused bicyclo[m.n.k]alkane derivatives (i.e., bicyclo[4.1.1]octanes, bicyclo[2.2.1]heptanes, bicyclo[3.2.1]octanes, bicyclo[3.1.0]hexanes, and bicyclo[4.2.0]heptanes). The scope and limitations of the method were established, and applicability to the multigram synthesis of target bicyclic compounds was illustrated. Using the developed protocols, over 50 mono- and bifunctional building blocks relevant to medicinal chemistry were prepared. The synthesized compounds are promising isosteres of benzene and cycloalkane rings, which is confirmed by their physicochemical and structural characterization (pKa, LogP, and exit vector parameters (EVP)). Rules of thumb for the upcoming isosteric replacement studies were proposed. Bicyclic molecule ; Cycloalkane ; Chemistry ; Intramolecular force ; Alkane ; Alkylation ; Halogenation ; Combinatorial chemistry ; Organic chemistry ; Stereochemistry ; Hydrocarbon ; Catalysis Organic Chemistry Cycloaddition Reactions ; Chemistry and Chemical Engineering ; Chemical Reaction Mechanisms
Authors: Naoto Inai | Shigehiro Yamaguchi | Takeshi Yanai
Source: ChemRxiv (preprint, 2023-07-31)
Field: Chemistry — Physical and Theoretical Chemistry

Theoretical Insight into the Effect of Phosphorus Oxygenation on Nonradiative Decays: Comparative Analysis of P-Bridged Stilbene Analogs Incorporation of phosphorus element into a 𝜋-conjugated skeleton offers valuable prospects for adjusting the electronic structure of the resulting functional 𝜋-electron systems. The trivalent phosphorus has the potential to decrease the LUMO level through the 𝜎∗-𝜋∗ interaction, which is further enhanced by its oxygenation to the pentavalent P center. This study shows that utilizing our computational analysis to examine excited-state dynamics based on radiative/nonradiative rate constants and fluorescence quantum yield (ΦF) is effective for analyzing the photophysical properties of P-containing organic dyes. We theoretically investigate how the trivalent phosphanyl group and pentavalent phosphine oxide moiety affect radiative and nonradiative decay processes. We evaluate four variations of P-bridged stilbene analogs. Our analysis reveals that the primary decay pathway for photo-excited bis-phosphanyl-bridged stil- bene is the intersystem crossing (ISC) to the triplet state and nonradiative. The oxidation of the phosphine moiety, however, suppresses the ISC due to the relative destabilization of the triplet states. The calculated rate constants match an increase in experimental ΦF from 0.07 to 0.98, as simulated from 0.23 to 0.94. The reduced HOMO–LUMO gap supports a red shift in the fluorescence spectra relative to the phosphine analog. The thiophene-fused variant with the non-oxidized trivalent P cen- ter exhibits intense emission with a high ΦF, 0.95. Our prediction indicates that the ISC transfer is obstructed owing to relatively destabilized triplet state induced by the thiophene substitution. Conversely, the thiophene-fused analog with the phosphine ox- ide moieties triggers a high-rate internal conversion mediated by conical intersection, leading to a decreased ΦF. Intersystem crossing ; Thiophene ; Chemistry ; Photochemistry ; Moiety ; HOMO/LUMO ; Excited state ; Reaction rate constant ; Phosphine ; Quantum yield ; Fluorescence ; Stereochemistry ; Molecule ; Singlet state ; Organic chemistry ; Kinetics Photochemistry and Electron Transfer Studies ; Porphyrin and Phthalocyanine Chemistry ; Organic Light-Emitting Diodes Research
Authors: Joëlle Mérgola-Greef | Bruce F. Milne
Source: Physical Chemistry Chemical Physics (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

First-principles study of electronic and optical properties in 1-dimensional oligomeric derivatives of telomestatin Real-space self-interaction corrected (time-dependent) density functional theory has been used to investigate the ground-state electronic structure and optical absorption profiles of a series of linear oligomers inspired by the natural product telomestatin. Length-dependent development of plasmonic excitations in the UV region is seen in the neutral species which is augmented by polaron-type absorption with tunable wavelengths in the IR when the chains are doped with an additional electron/hole. Combined with a lack of absorption in the visible region this suggests these oligomers as good candidates for applications such as transparent antennae in dye-sensitised solar energy collection materials. Due to strong longitudinal polarisation in their absorption spectra, these compounds are also indicated for use in nano-structured devices displaying orientation-sensitive optical responses. Density functional theory ; Absorption (acoustics) ; Absorption spectroscopy ; Polaron ; Electronic structure ; Doping ; Materials science ; Chemistry ; Optoelectronics ; Atomic electron transition ; Molecular physics ; Chemical physics ; Spectral line ; Electron ; Optics ; Physics ; Computational chemistry Quantum Dots Synthesis And Properties ; Gold and Silver Nanoparticles Synthesis and Applications ; Molecular Junctions and Nanostructures
Authors: Smitaroopa Kahali | Sujit Das | Ravinder Kumar | Kunika Gupta | Rajasree Kundu | Baivabi Bhattacharya | Arnab Nath | Ravindra Venkatramani | Ankona Datta
Source: ChemRxiv (preprint, 2023-12-28)
Field: Chemistry — Spectroscopy

A Water-soluble, Cell-permeable Mn(II) Sensor Enables Visualization of Manganese Dynamics in Live Mammalian Cells Central roles of Mn2+ ions in immunity, brain function, and photosynthesis, necessitate probes for tracking this essential metal ion in living systems. However, developing a cell-permeable, fluorescent sensor for selective imaging of Mn2+ ions in the aqueous cellular milieu has remained a challenge. This is because Mn2+ is a weak binder to ligand scaffolds when compared to other physiological metal ions, in water. Further, Mn2+ ions quench fluorescent dyes leading to turn-off sensors that are not applicable for in vivo imaging. Hence, the few existing small molecule-based sensors are not exclusively Mn2+ ion selective and suffer from low aqueous solubility. The only reported protein and DNA-based probes are cell-impermeable and show either sub-optimal selectivity or low sensitivity. Here we report a novel, completely water-soluble, reversible, fluorescent turn-on, Mn2+ selective sensor with a Kd of 1.4 µM for Mn2+ ions. The probe enters cells within 15 min of direct incubation and was applied to image Mn2+ ions in living mammalian cells in both confocal fluorescence intensity and lifetime-based set-ups. In a key experiment, we show that the probe was able to visualize Mn2+ dynamics in live cells revealing differential Mn2+ localization and uptake dynamics in disease model cells replicating conditions of Mn-transporter defect induced Parkinsonism when compared to normal cells. The computationally-designed sensor with a 620 nM limit-of-detection for Mn2+ in water, distinctly overcomes selectivity, sensitivity, and cell-permeability issues associated with the few reported Mn2+ probes, thus opening floodgates to elucidate the hitherto intractable mammalian Mn2+ homeostasis. Fluorescence ; Metal ions in aqueous solution ; Ion ; Biophysics ; Live cell imaging ; Chemistry ; Aqueous solution ; Fluorescence-lifetime imaging microscopy ; Selectivity ; Membrane permeability ; Manganese ; Membrane ; Cell membrane ; Molecule ; Photochemistry ; Cell ; Biochemistry ; Biology ; Physics Molecular Sensors and Ion Detection ; Advanced biosensing and bioanalysis techniques ; Trace Elements in Health
Authors: Thomas Pretto | Marina Franca | Veronica Zani | Silvia Gross | Danilo Pedron | Roberto Pilot | Raffaella Signorini
Source: Proceedings of the World Congress on Recent Advances in Nanotechnology (article, 2023-03-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Anatase Nanoparticles for Raman Nanothermometry The determination of the local temperature is an interesting and intriguing topic in the nanotechnology and nanomedicine world, in terms of tuning the best noninvasive measurement protocol and identification of the more versatile and performing material.In this paper, the Raman technique and titania NPs have been exploited for the realization of a new optical nanotermometer.Biocompatible titania NPs have been properly synthesized, following a combination of sol-gel and solvothermal green synthesis approaches, with the aim of obtaining samples of pure anatase, characterized by crystallite dimensions defined and good control over the final morphology and dispersibility.Powder XRD measurements and room temperature Raman measurements confirmed that the synthesized samples are single-phase anatase.The SEM images clearly showed the nanometric dimension of NPs.Stokes and anti-Stokes Raman measurements, collected with the excitation laser at 514.5 nm (CW Ar/Kr ion laser), substantiate the possibility of evaluating the local temperature, which has been tested in the range of 298 -313 K, a range of interest for biological applications.The power of the laser has been carefully chosen in order to avoid eventual heating due to the laser irradiation.The data show that TiO2 NPs possess a high sensitivity and low uncertainty in the range of a few degrees as Raman nanothermometer material. Raman spectroscopy ; Anatase ; Nanoparticle ; Materials science ; Computer science ; Nanotechnology ; Chemistry ; Physics ; Optics ; Photocatalysis Gold and Silver Nanoparticles Synthesis and Applications ; Quantum Dots Synthesis And Properties ; Advanced Nanomaterials in Catalysis
Authors: Xuelian Chen | Qigu Huang
Source: Gels (article, 2023-12-31)
Field: Materials Science — Polymers and Plastics

Model Simulation and Rheological Research on Crosslinking Behavior of Polyethylene Resin The crosslinking behavior of polyethylene (PE) determines its exceptional performance and application. In this study, we investigated the crosslinking behaviors of different PE resins through model simulation and rheological methods. Specifically, the mathematical equation of "S" model was established for PE resin. According to this equation, the optimal maximum gel content for high-density polyethylene (HDPE) was found to be around 85%. Moreover, the maximum crosslinking degrees for different PE resins depended largely on their density and molecular weight. The melt viscosities before crosslinking in PE resins were highly influenced by their melt index. The higher melt indexes resulted in the lower storage moduli, improving melt processability during processing. In addition, the crosslinking rates of PE resins were strongly influenced by peroxide concentration, independent of PE resin structures. For high molecular weight and low-density PE resins, they exhibited decreased ti values, increased A<sub>0</sub> values, and decreased k6 values. However, there were no noticeable variations in the values of k2 and phi among different PE resins. All simulated modeling outcomes showed remarkable consistency with the experimental rheological data. These findings are of strong significance in the industrial manufacture of PE resin. Rheology ; High-density polyethylene ; Materials science ; Polyethylene ; Composite material ; Peroxide ; Low-density polyethylene ; Polymer chemistry ; Organic chemistry ; Chemistry Polymer crystallization and properties ; Mechanical Behavior of Composites ; Natural Fiber Reinforced Composites
Authors: Jagirdar Sikandar Zoolquernain Farooq | Furquan Nazimuddin Khan
Source: International Journal of experimental research and review (article, 2023-12-30)
Field: Chemistry — Analytical Chemistry

QbD-Driven Development and Validation of a Bioanalytical LC–MS Method for Quantification of Paliperidone in Human Plasma This paper discusses how a Quality by Design (QbD) strategy was used to develop and test an HPLC-MS bioanalytical method for detecting plasma Paliperidone concentration. A C18 column and an isocratic mobile phase of organic solvents and water were improved for chromatographic separation. To optimise method performance, Box-Behnken design was used to study column temperature, mobile phase composition, and flow rate. The research used a logical QbD methodology to build an optimised HPLC-MS technology that meets US-FDA standards. Validation studies evaluated selectivity, sensitivity, carryover effects, matrix factor determination, linearity, accuracy and precision testing, recovery, dilution veracity, ruggedness, stability, and reinjection reproducibility, with supporting documentation. The validation studies showed the method's suitability and met acceptance requirements. The QbD framework was successfully used to build and validate an HPLC-MS bioanalytical technique for Paliperidone measurement in human plasma. This method improves chromatographic performance and Paliperidone quantification in clinical and pharmacokinetic studies. Bioanalysis ; Quality by Design ; Chromatography ; Reproducibility ; Human plasma ; Chemistry ; Computer science ; Particle size Analytical Methods in Pharmaceuticals ; Pesticide Residue Analysis and Safety ; Antibiotics Pharmacokinetics and Efficacy
Authors: Hao Hu | K. Ullakko
Source: Diffusion and defect data, solid state data. Part B, Solid state phenomena/Solid state phenomena (article, 2023-06-06)
Field: Materials Science — Materials Chemistry

Selective Etch for Micromachining Process in Manufacturing Hybrid Microdevices composed of Ni-Mn-Ga and Silicon Layers The goal of this study is to make selective etch possible for the next generation of MEMS(microelectromechanical systems) devices that are composed Ni-Mn-Ga and silicon layers. Due tothe large magnetic-field-induced strains of Ni-Mn-Ga, sensing and actuating components can be fab-ricated in the Ni-Mn-Ga layers. Other functional components can be manufactured in the silicon layer.Single crystalline Ni-Mn-Ga alloys that are grown by using the Bridgman vertical growth techniquehave so far obtained the largest magnetic field-induced strain (MFIS), a magnetic shape memory(MSM) effect. Similar to silicon wafers, Ni-Mn-Ga wafers are also sliced from crystal-oriented singlecrystalline ingots. To fabricate hybrid MEMS devices such as micromanipulators and robots, lab-on-chip containing micropump manifolds and valves, or vibration energy harvesters, the fabricationprocesses used for MEMS devices will be also used to fabricate components in the Ni-Mn-Ga layer ofthe hybrid MEMS devices. One of the most important processes for MEMS fabrication is the structur-ing of materials by chemical etching. The main goal of this study is to obtain evidence that the etchantetches silicon but not Ni-Mn-Ga and to identify an etchant that etches Ni-Mn-Ga but not silicon. Thepresent paper reports on a novel experiment in dissolving Ni-Mn-Ga alloys. An etchant compositionof 69% HNO3, 98% H2SO4, and CuSO4•5H2O is proposed for dissolving Ni-Mn-Ga alloys and thevariation in the dissolution rate by adjusting the concentrations of HNO3 and ultrapure water (UPW)is demonstrated. This etchant was demonstrated to etch Ni-Mn-Ga but not silicon. The HF+HNO3acidic solution commonly used for etching silicon does not dissolve Ni-Mn-Ga alloys. Materials science ; Microelectromechanical systems ; Wafer ; Silicon ; Dissolution ; Etching (microfabrication) ; Bulk micromachining ; Fabrication ; Optoelectronics ; Layer (electronics) ; Surface micromachining ; Ultrapure water ; Metallurgy ; Nanotechnology ; Chemical engineering Shape Memory Alloy Transformations ; Magnetic and transport properties of perovskites and related materials ; Aeroelasticity and Vibration Control
Authors: C.C. Koch | Anke-Susanne Müller | Martin Kahlmeyer | Tino Riske | Inga Melnyk | Lars Dähne | Dennis Kaden | Michael Baitinger | Andreas Fery | Stefan Böhm
Source: Smart Materials and Structures (article, 2023-07-03)
Field: Materials Science — Polymers and Plastics

Mechanically induced dye-release from polyurea microcapsules in a rubbery adhesive Abstract Especially in the building industry the demand for in situ monitoring concepts of adhesive joints persists. In a new approach, microcapsules filled with special dyes, are added into a rubbery adhesive. Certain stress levels within the adhesive lead to a breakage of the capsules, which release their liquid cores. This results in a detectable colour change and thus, enables non-destructive condition monitoring of the bond. Dye-filled polyurea microcapsules were produced by interfacial polymerization by varying synthesis parameters while their influence on capsule morphology and wall thickness was determined. The morphology and thermal properties of the microcapsules were characterized by scanning electron microscopy and dynamic differential calorimetry, respectively. Subsequently, the method of nanoindentation was used to study the deformation and fracture behaviour of the microcapsules. Finally, it was analysed to what extent the microcapsules break within a polymer matrix, e.g. by critical stress levels or deformations. This development is a new quality assurance method for glass façades. Polyurea ; Materials science ; Adhesive ; Composite material ; Differential scanning calorimetry ; Polymer ; Polyurethane ; Nanoindentation ; Polymerization ; Deformation (meteorology) ; Morphology (biology) Polymer composites and self-healing ; Building materials and conservation ; Silicone and Siloxane Chemistry