jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Sergio da Cunha | Nataliya Shcherbakova | Vincent Gerbaud | Patrice Bacchin
Source: Journal of Fluid Mechanics (article, 2023-02-14)
Field: Chemistry — Physical and Theoretical Chemistry

Characterisation of fully developed and equilibrium states of non-electrolyte diffusiophoretic systems via numerical simulations Diffusiophoresis takes place when a particle in solution moves due to the presence of a solute concentration gradient. This phenomenon is often studied under some simplifying assumptions, such as negligible diffusive layer thickness or infinite diffusion coefficient. In this work we simulate diffusiophoresis without these simplifications. The goal of this numerical study is to investigate equilibrium and fully developed states of non-electrolyte phoretic systems. Simulation results show that equilibrium states depend on solute diffusivity and on a reference solute concentration far from the particle. An expression is regressed that gives the (equilibrium) diffusiophoretic velocity as a function of solute concentration gradient, solute diffusion coefficient and the reference solute concentration far from the particle. A different set of results reveals that the state of phoretic systems does not depend on the initial conditions when time goes to infinity. This motivates the definition of fully developed states, designating those systems whose properties no longer depend on initial conditions. Apart from these findings, this work also depicts the effect of solute–interface interactions on diffusiophoresis. Simulation results for two solid particles with different interaction potentials are used to illustrate particle separation via diffusiophoresis. Finally, values of particle mobility are calculated for different solute–interface attraction strengths. These results are compared with another work in the literature, which studies polymer diffusiophoresis via molecular simulations (Ramírez-Hinestrosa et al. , J. Chem. Phys. , vol. 152, 2020, p. 164901). Work (physics) ; Diffusion ; Particle (ecology) ; Electrolyte ; Thermal diffusivity ; Thermodynamics ; Concentration gradient ; Statistical physics ; Thermodynamic equilibrium ; Physics ; Mechanics ; Chemical physics ; Materials science ; Chemistry ; Chromatography ; Geology Electrostatics and Colloid Interactions ; Microfluidic and Bio-sensing Technologies ; Nanopore and Nanochannel Transport Studies
Authors: Jairo Eduardo Márquez Díaz
Source: Journal of pharmacology & clinical research (article, 2023-11-22)
Field: Materials Science — Biomaterials

Nanotechnology in Pharmacology: Advances and Applications in Drug Delivery Nanotechnology has transformed pharmacology by allowing the development of more efficient drug delivery systems with fewer side effects.The present review aims to present an overview of the recent advances and applications of nanotechnology in drug delivery, highlighting its potential to improve the diagnosis and treatment of diseases.Different applications of nanoparticles and nanocarriers are analyzed for the treatment of various diseases, where technology is combined with medicine to explore advanced delivery systems and understand at the molecular level the mechanisms that govern cells.Nanotechnology has allowed the development of more efficient drug delivery systems with fewer side effects.Nanomedicine uses nanotechnology to improve drug delivery to specific organs, allowing doctors to achieve the best possible effectiveness and safety of the medications they administer.Nanoparticles are one of the most used tools in nanotechnology for the delivery of drugs and advanced treatments.These nanoparticles, due to their size, shape and surface chemistry affect all aspects of the interaction between the body and the drug. Drug delivery ; Nanotechnology ; Drug ; Pharmacology ; Medicine ; Engineering ethics ; Engineering ; Materials science Nanoparticle-Based Drug Delivery
Authors: Bettina Baumgartner | P. Tim Prins | Jaap N. Louwen | Matteo Monai | Bert M. Weckhuysen
Source: ChemRxiv (preprint, 2023-01-19)
Field: Chemistry — Inorganic Chemistry

The Role of Water in Carbon Dioxide Adsorption in Porphyrinic Metal-Organic Frameworks Capturing and converting CO2 in photoactive, porous materials to mimic photosynthesis is not only an appealing but also an important approach to combat increasing CO2 concentrations. Porphyrinic Zr-based metal-organic frameworks (MOFs) incorporate a photoactive dye in a porous material and are therefore promising candidates for artificial photosynthesis. The photochemical conversion of CO2 relies on the interactions between CO2, the proton source H2O, and the photoactive sites in the MOF pores. However, our understanding of these interactions and the photoreaction mechanism is still rather limited. Here, we studied the initial step of the artificial photosynthesis: CO2 sorption and activation in the presence of water. We have developed a combined vibrational and visible spectroscopic setup to simultaneously monitor the adsorption of CO2 into porphyrinic Zr-MOFs, namely PCN-222 and PCN-223, and the photophysical changes in the porphyrin linker as function of water concentration. Computational simulations further corroborate the experimentally obtained adsorption enthalpies. We found a shift of CO2 sorption site from the Zr-cluster to the center of the porphyrin macrocycle when PCN-MOFs were brought in contact with humidity greater than the water pore condensation concentration. The shift in sorption site was accompanied by a bending of the porphyrin macrocycle, which induced a change in color and, thus, a change in spectral overlap with light. Furthermore, CO2/H2O competition experiments revealed that the exchange of CO2 by H2O is pore-size-dependent. Therefore, both humidity and pore-size allow to tune the CO2 sorption site, CO2 capacity, and light harvesting in porphyrinic MOFs, which are key factors for CO2 photoreduction. Sorption ; Porphyrin ; Adsorption ; Metal-organic framework ; Photochemistry ; Chemistry ; Chemical engineering ; Schumann resonances ; Materials science ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Catalytic Processes in Materials Science ; Covalent Organic Framework Applications
Authors: S. Kovacevic | W. Ali | E. Martínez-Pañeda | J. LLorca
Source: arXiv (Cornell University) (preprint, 2023-04-08)
Field: Materials Science — Biomaterials

Phase-field modeling of pitting and mechanically-assisted corrosion of Mg alloys for biomedical applications A phase-field model is developed to simulate the corrosion of Mg alloys in body fluids. The model incorporates both Mg dissolution and the transport of Mg ions in solution, naturally predicting the transition from activation-controlled to diffusion-controlled bio-corrosion. In addition to uniform corrosion, the presented framework captures pitting corrosion and accounts for the synergistic effect of aggressive environments and mechanical loading in accelerating corrosion kinetics. The model applies to arbitrary 2D and 3D geometries with no special treatment for the evolution of the corrosion front, which is described using a diffuse interface approach. Experiments are conducted to validate the model and a good agreement is attained against in vitro measurements on Mg wires. The potential of the model to capture mechano-chemical effects during corrosion is demonstrated in case studies considering Mg wires in tension and bioabsorbable coronary Mg stents subjected to mechanical loading. The proposed methodology can be used to assess the in vitro and in vivo service life of Mg-based biomedical devices and optimize the design taking into account the effect of mechanical deformation on the corrosion rate. The model has the potential to advocate further development of Mg alloys as a biodegradable implant material for biomedical applications. Corrosion ; Materials science ; Pitting corrosion ; Dissolution ; Diffusion ; Phase (matter) ; Metallurgy ; Service life ; Composite material ; Chemical engineering ; Chemistry ; Thermodynamics ; Engineering Magnesium Alloys: Properties and Applications ; Aluminum Alloy Microstructure Properties ; Aluminum Alloys Composites Properties
Authors: Dil Nawaz | TARIQ PERVEZ | Muhammad Aqib Shabbir
Source: Pakistan Postgraduate Medical Journal (article, 2023-09-30)
Field: Chemistry — Organic Chemistry

COMPARATIVE EVALUATION OF PROTEIN AND LIGAND-BASED DOCKING PROTOCOLS THROUGH PROTEIN PHOSPHATASE SLINGSHOT HOMOLOG 2 COMPLEX A molecular docking study is used to investigate the interactions between the two molecules. These interactions may be covalent, hydrogen, or Van der Waals forces. Various web-based and stand-alone tools have been discovered for molecular docking analysis. In this study, we performed a comparison between web-based and stand-alone docking tools to evaluate the accuracy. Five web-based tools i) Dockthor, ii) Patchdock, iii) RPBA Web, iv) Swissdock, v) Patinum and two stand-alone tools1) Autodock Vina &amp; 2) Hex were selected for the evaluation of the tool`s accuracy in term of best conformations with minimum binding energies. Protein phosphatase Slingshot homolog 2, SSH2 (PDBID: 2NT2) and four of its related proteins were used as the key proteins in this study. Ligands and Proteins interacting with SSH2 in the Novel signalling pathway were investigated through above mentioned tools.&#x0D; Docking (animal) ; AutoDock ; van der Waals force ; Chemistry ; Phosphatase ; Computational biology ; Protein–ligand docking ; Molecular dynamics ; Biochemistry ; Computational chemistry ; Molecule ; Enzyme ; Biology ; In silico ; Virtual screening ; Gene Synthesis and biological activity ; Enzyme function and inhibition ; Computational Drug Discovery Methods
Authors: Guadalupe Pérez | Héctor M. Poggi‐Varaldo
Source: Tendencias en energías renovables y sustentabilidad . (article, 2023-11-23)
Field: Materials Science — Biomaterials

Producción de ácido hialurónico con residuos orgánicos como un producto de valor agregado para integrar una biorrefinería tipo HMZS que procesa residuos sólidos urbanos Las biorrefinerías (BRF) que procesan residuos sólidos urbanos con una configuración “HMZS” tienen las etapas de producción: Biohidrógeno (H), Metano (M), enzimas de interés industrial (Z) y licores sacarificados (S), en esta última etapa se propone el aprovechamiento los licores sacarificados como sustrato para la producción de ácido hialurónico (AH). En este trabajo se elaboró una revisión crítica del perfil de producción microbiana de AH y la utilización de residuos orgánicos como sustrato para identificar el proceso de producción de AH que pueda adaptarse en laetapa S de la BRF-HMZS. En la producción microbiana de AH se utilizan cepas de Streptococcus zooepidemicus que naturalmente producen AH y alcanza concentraciones de 6.9 g/L, sin embargo, debido a la patogenicidad de dichas bacterias se han desarrollado bacterias y hongos recombinantes que son inocuos y mediante transformación genética alcanzan concentraciones de 28.7 g/L. Hasta ahora la información sobre residuos orgánicos como sustrato en la producción de AH es muy escasa y se ha reportado el uso de estos sustratos para Streptococcus zooepidemicus únicamente. Los tipos de residuos orgánicos que se han explorado son savia de palma, melazas de caña, licor de maíz fermentado y almidón como la fuente de carbono (C). Este último ha mostrado la concentración de AH de 6.7 g/L mientras que para proveer la fuente de nitrógeno (N) se ha explorado la proteína de soya, residuos de pescado y lana de oveja que han alcanzado concentraciones de 4.0 g/L. Finalmente, la evaluación económica ha mostrado menores costos de producción de AH cuando se utilizan los residuos orgánicos como fuentes de C y/o N en comparación con las fuentes de C y N convencionales. La producción microbiana de AH aprovechando los licores sacarificados proveería de un producto de alto valor agregado para dar sostenibilidad ambiental y económica a las BRF-HMZS. Chemistry Electrospun Nanofibers in Biomedical Applications ; Biofuel production and bioconversion ; Enzyme Catalysis and Immobilization
Authors: Debopriya Dutta | Subhrajit Mukherjee | Michael Uzhansky | Pranab Kumar Mohapatra | Ariel Ismach | Elad Koren
Source: arXiv (Cornell University) (preprint, 2023-01-02)
Field: Materials Science — Materials Chemistry

Edge-based 2D alpha-In2Se3-MoS2 ferroelectric field effect device Heterostructures based on two dimensional (2D) materials offer the possibility to achieve synergistic functionalities which otherwise remain secluded by their individual counterparts. Herein ferroelectric polarization switching in alpha-In2Se3 has been utilized to engineer multilevel non-volatile conduction states in partially overlapping alpha-In2Se3-MoS2 based ferroelectric semiconducting field effect device. In particular, we demonstrate how the intercoupled ferroelectric nature of alpha-In2Se3 allows to non-volatilely switch between n-i and n-i-n type junction configurations based on a novel edge state actuation mechanism, paving the way for sub-nanometric scale non-volatile device miniaturization. Furthermore the induced asymmetric polarization enables enhanced photogenerated carriers separation resulting in extremely high photoresponse of 1275 AW-1 in the visible range and strong non-volatile modulation of the bright A- and B- excitonic emission channels in the overlaying MoS2 monolayer. Our results show significant potential to harness the switchable polarization in partially overlapping alpha-In2Se3-MoS2 based FeFETs to engineer multimodal non-volatile nanoscale electronic and optoelectronic devices. Ferroelectricity ; Heterojunction ; Monolayer ; Optoelectronics ; Polarization (electrochemistry) ; Materials science ; Nanotechnology ; Nanoscopic scale ; Miniaturization ; Dielectric ; Chemistry 2D Materials and Applications ; Perovskite Materials and Applications ; Advanced Sensor and Energy Harvesting Materials
Authors: S Poongothai | R Srinivasan | M Rama
Source: International Journal of Pharmaceutical Quality Assurance (article, 2023-09-25)
Field: Chemistry — Spectroscopy

A Correlative Dissolution Study of Oral Drug Delivery Systems through Reverse Phase-HPLC Analysis Oral drug administration is essential for treating diverse diseases due to its acceptable route, non-invasiveness, minimal off-target side effects, versatility, and painless patient delivery. However, multiple drug accessibility is increasing currently but there is often a deficiency of indication in developing procedures with assessment of two diverse medicinal formulations. Oral administration of a novel antiepileptic drug, levetiracetam in grouping with either L-dopa unaccompanied or L-dopa/Ropinirole treatments was associated with dyskinesia. Altered shooting patterns of neurons relating to a compulsive harmonization process may back to the origin of dyskinesia. The current study aims to develop a dissolution technique and validate the antiparkinsonian drug-ropinirole and antiepileptic drug-levetiracetam tablets by RP-HPLC, which plays a major part in pharmaceutical formulations. The optimal dissolution conditions were experienced for the products respective to the pharmaceutical formulation and applied to assess the dissolution profiles. Ideal settings for the dissolution method were 500 mL of pH of 4.0 citrate buffer, 50 rpm and 250 nm for ropinirole tablets and 900 mL of distilled water, the rotation speed of paddle 50 rpm and 217 nm for levetiracetam tablets, then 3.84 and 3.87 minutes were set as the retention time of ropinirole and levetiracetam tablets, respectively. Technique optimization and validation process helps to reduce the bioequivalence of both dosage forms. The current study ensues detailed information on the drug release, even if there is a change in pH medium, filter, rpm, instrumentation, etc. Focusing on current pharmaceutical sciences, the proposed correlative dissolution study coupled with RP-HPLC analysis could offer a holistic insight into the performance of future oral drug delivery systems Ropinirole ; Levetiracetam ; Pharmacology ; Bioequivalence ; Drug ; Dosage form ; Dissolution testing ; Medicine ; Immediate release ; Pharmaceutical formulation ; Bioavailability ; Biopharmaceutics Classification System ; Epilepsy ; Internal medicine ; Levodopa Analytical Chemistry and Chromatography ; Drug Solubulity and Delivery Systems ; Analytical Methods in Pharmaceuticals
Authors: Subhajit Ghosh | Sergey Rumyantsev | Alexander A. Balandin
Source: arXiv (Cornell University) (preprint, 2023-12-26)
Field: Materials Science — Electronic, Optical and Magnetic Materials

The Noise of the Charge Density Waves in NbSe$_3$ Nanowires -- Contributions of Electrons and Quantum Condensate Low-frequency electronic noise in charge-density-wave van der Waals materials has been an important characteristic, providing information about the material quality, phase transitions, and collective current transport. However, the noise sources and mechanisms have not been completely understood, particularly for the materials with a non-fully gapped Fermi surface where the electrical current includes components from individual electrons and the sliding charge-density wave. We investigated noise in nanowires of quasi-one-dimensional NbSe$_3$, focusing on a temperature range near the Pearls transition ~ 145 K. The data analysis allowed us to separate the noise produced by the individual conduction electrons and the quantum condensate of the charge density waves before and after the onset of sliding. The noise as a function of temperature and electric bias reveals several intriguing peaks. We explained the observed features by the depinning threshold field, the creep and sliding of the charge density waves, and the possible existence of the hidden phases. It was found that the charge density wave condensate is particularly noisy at the moment of depinning. The noise of the collective current reduces with the increasing bias voltage in contrast to the noise of the individual electrons. Our results shed light on the behavior of the charge density wave quantum condensate and demonstrate the potential of noise spectroscopy for investigating the properties of low-dimensional quantum materials. Condensed matter physics ; Noise (video) ; Charge density wave ; Physics ; Electron ; Quantum noise ; Charge density ; Quantum ; Quantum mechanics ; Superconductivity Organic and Molecular Conductors Research ; Mechanical and Optical Resonators ; Cold Atom Physics and Bose-Einstein Condensates
Authors: Saufa Taslima | Awan Pelawi | Putra Raja P P Sitohang
Source: Jurnal Ilmiah METADATA (article, 2023-09-01)
Field: Materials Science — Materials Chemistry

APPLICATION OF BASIC PHYSICS CONCEPTS TO THE INTERACTION OF RADIATION WITH MATERIALS IN RADIOLOGICAL EXAMINATIONS This study quantitatively evaluates the application of fundamental physics concepts, namely the attenuation and scattering of ionizing radiation, in diagnostic radiology examinations, with the aim of validating predictions of radiation (X-ray) interactions with various types of biological tissues and phantom materials. Based on the Beer-Lambert theory and scattering model, this study tests the hypothesis that the physical properties of matter (atomic number, density) significantly influence the attenuation and scattering coefficients, which correlate with image quality and dose profiles. Using a quantitative experimental design with 30 phantom and biological samples, radiation intensity measurements were performed with a calibrated detector under controlled acquisition parameters, as well as digital image quality evaluation. The results show a strong correlation between radiation attenuation and atomic number and density of the material (e.g., bone attenuation is 2.5x higher than soft tissue, p &lt; 0.001, d = 1.8), as well as the dominance of Compton scattering which is directly proportional to material thickness and scattering angle. A positive correlation was also found between the scattering/transmission ratio and image artifacts such as beam hardening. In conclusion, an understanding of fundamental physics is crucial for predicting radiation interactions, providing theoretical contributions to accurate simulation models, and providing practical implications for optimizing acquisition parameters, image reconstruction algorithms, and radiation dose management to improve diagnostic quality. Imaging phantom ; Attenuation ; Scattering ; Compton scattering ; Image quality ; Ionizing radiation ; Radiation ; Detector ; Dosimetry Graphite, nuclear technology, radiation studies ; Nuclear Physics and Applications ; Radioactivity and Radon Measurements
Authors: Khagani Farzulla Mammadov
Source: ScienceRise (article, 2023-12-29)
Field: Materials Science — Materials Chemistry

Adsorption’s regularities of radionuclides on adsorbents from solutions The object of research: The object of research is the uranium isotopes were found in the soil of the locations of numerous thermal and cold springs in the Kalbajar region of Azerbaijan in the same proportions as in natural uranium deposits.&#x0D; Investigated problem: Uranium isotopes were transferred from soil samples to solutions. İnvestigated problem of scientific work is study of regularities of adsorption of uranium isotopes from solutions on the surfaces of various adsorbents.&#x0D; The main scientific results: It is defined high adsorption properties of DOWEX HCR granular elastomer, activated carbon and expanded clay on the result of researches. The activation’s energy of desorption of uranium isotopes from the surface of adsorbents were determined. Relatively low values (22.1–26.3 kJ/mol) of the activation’s energy of desorption of uranium isotopes from the surface of adsorbents indicate the absence of the chemical nature of sorption and the presence of only weak van der Waals forces between the absorbed isotopes and the surface of the adsorbents.&#x0D; The area of practical use of the research results: The regularities of adsorption of uran isotopes on adsorbent masses from aqueous solutions can be used as an original cleaning method of the drain water of the physical stage of crude oil refining or other radiochemical processes to the norms for waste water.&#x0D; Innovative technological product: It was determined based on the research, that the concentration of radon in the waters of most springs of the “Istisu” deposit is below the regulatory permissible value (60 Bq/l), which indicates the suitability of these spring waters for use in medical treatment procedures.&#x0D; Scope of the innovative technological product: It is planned to resume (prevented more than 40 years ago due to global regional problems) the production of the original trademark – “Istisu” medicinal water, with the concentration of radon below the standard value. Considering the two-fold decrease in radon concentration in water over four days, the waters of the individual sources examined, with a 100-fold high radon content, after a certain time (several months) can also be used for use in medical procedures, which allows their transportation to large distances Adsorption ; Radionuclide ; Chemistry ; Radiochemistry ; Environmental chemistry ; Chemical engineering ; Physics ; Physical chemistry ; Nuclear physics ; Engineering Graphite, nuclear technology, radiation studies ; Advanced Data Processing Techniques ; Field-Flow Fractionation Techniques