jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Molly Lightowler | Shuting Li | Xiao Ou | Jungyoun Cho | Binbin Liu | Ao Li | Gerhard Höfer | Jiaoyan Xu | Taimin Yang | Xiaodong Zou | Ming Lü | Hongyi Xu
Source: Angewandte Chemie International Edition (article, 2024-02-21)
Field: Materials Science — Materials Chemistry

Phase Identification and Discovery of an Elusive Polymorph of Drug‐Polymer Inclusion Complex Using Automated 3D Electron Diffraction 3D electron diffraction (3D ED) has shown great potential in crystal structure determination in materials, small organic molecules, and macromolecules. In this work, an automated, low-dose and low-bias 3D ED protocol has been implemented to identify six phases from a multiple-phase melt-crystallisation product of an active pharmaceutical ingredient, griseofulvin (GSF). Batch data collection under low-dose conditions using a widely available commercial software was combined with automated data analysis to collect and process over 230 datasets in three days. Accurate unit cell parameters obtained from 3D ED data allowed direct phase identification of GSF Forms III, I and the known GSF inclusion complex (IC) with polyethylene glycol (PEG) (GSF-PEG IC-I), as well as three minor phases, namely GSF Forms II, V and an elusive new phase, GSF-PEG IC-II. Their structures were then directly determined by 3D ED. Furthermore, we reveal how the stabilities of the two GSF-PEG IC polymorphs are closely related to their crystal structures. These results demonstrate the power of automated 3D ED for accurate phase identification and direct structure determination of complex, beam-sensitive crystallisation products, which is significant for drug development where solid form screening is crucial for the overall efficacy of the drug product. Drug discovery ; Inclusion (mineral) ; Identification (biology) ; Electron diffraction ; Drug ; Crystallography ; Polymer ; Computational biology ; Diffraction ; Materials science ; Chemistry ; Bioinformatics ; Biology ; Physics ; Organic chemistry ; Mineralogy ; Pharmacology ; Optics X-ray Diffraction in Crystallography ; Crystallography and molecular interactions ; Crystallization and Solubility Studies
Authors: Nataliia Staroselska | Mykola Korchak | Tetiana Ovsiannikova | Tetiana Falalieieva | Oleksandr Ternovyi | Валерій Крайнов | Valentyna Mohutova | Л. П. Морозова | Р. А. Чудак | Roman Mylostyvyi
Source: Eastern-European Journal of Enterprise Technologies (article, 2024-02-28)
Field: Chemistry — Analytical Chemistry

Improving the technology of oxidative stabilization of rapeseed oil The object of the research is the oxidation process of rapeseed oil. Rapeseed oil is used for technical purposes, in the chemical and food industries, in particular, in the production of ecological fuel. Vegetable oils are subjected to oxidative deterioration processes, which are intensified under the conditions of access to oxygen, elevated temperatures, etc. Oxidation products worsen the technological properties and complicate the use of oils in chemical reactions. An important task is to improve the technology of oxidative stabilization of rapeseed oil, which is of great industrial importance. The oxidation process of refined deodorized rapeseed oil according to DSTU 8175 (CAS Number 120962-03-0) at a temperature of 110 °C was studied by the method of differential scanning calorimetry. The influence of different ratios of antioxidants (tocopherol, butylhydroxyanisole and butylhydroxytoluene) in the mixture on the oil induction period was determined. The total concentration of the antioxidant mixture in each experiment was 0.02 %. The induction period of the initial oil is 408.48 min. The rational ratios of the components of the antioxidant mixture were determined: tocopherol: butylhydroxyanisole (75:25) %; tocopherol: butylhydroxyanisole: butylhydroxytoluene (66.67:16.67:16.67) %. The corresponding oil induction periods were 579.75 min. and 561.55 min. The physico-chemical indicators of rapeseed oil after 12 months of storage at a temperature of (20±2) °C in its original form and with the addition of the developed antioxidant mixtures were determined. The peroxide value of the oil was 12.5, 4.59, 6.45 ½ O mmol/kg, respectively. The research results allow improving the technology of oxidative stabilization of rapeseed oil at elevated and standard temperatures. This will help to extend the oil shelf life, more efficiently and rationally use the oil in various areas Rapeseed ; Oxidative phosphorylation ; Chemistry ; Business ; Environmental science ; Food science ; Biochemistry Spectroscopy and Chemometric Analyses ; Advanced Scientific Research Methods ; Water Quality Monitoring and Analysis
Authors: Júlia Wilhelm | Klaas M. Pos
Source: Microbiology (article, 2024-02-15)
Field: Chemistry — Organic Chemistry

Molecular insights into the determinants of substrate specificity and efflux inhibition of the RND efflux pumps AcrB and AdeB Gram-negative bacterial members of the Resistance Nodulation and cell Division (RND) superfamily form tripartite efflux pump systems that span the cell envelope. One of the intriguing features of the multiple drug efflux members of this superfamily is their ability to recognize different classes of antibiotics, dyes, solvents, bile salts, and detergents. This review provides an overview of the molecular mechanisms of multiple drug efflux catalysed by the tripartite RND efflux system AcrAB-TolC from <i>Eschericha coli</i>. The determinants for sequential or simultaneous multiple substrate binding and efflux pump inhibitor binding are discussed. A comparison is made with the determinants for substrate binding of AdeB from <i>Acinetobacter baumannii</i>, which acts within the AdeABC multidrug efflux system. There is an apparent general similarity between the structures of AcrB and AdeB and their substrate specificity. However, the presence of distinct conformational states and different drug efflux capacities as revealed by single-particle cryo-EM and mutational analysis suggest that the drug binding and transport features exhibited by AcrB may not be directly extrapolated to the homolog AdeB efflux pump. Efflux ; Substrate (aquarium) ; Substrate specificity ; Chemistry ; Biology ; Computational biology ; Biochemistry ; Ecology ; Enzyme Synthesis and Biological Evaluation ; Viral Infections and Immunology Research ; Veterinary medicine and infectious diseases
Authors: Soumya Sarkar | Zirun Han | Maheera Abdul Ghani | Nives Strkalj | Jung Ho Kim | Yan Wang | Deep Jariwala | Manish Chhowalla
Source: Nano Letters (article, 2024-10-09)
Field: Materials Science — Materials Chemistry

Multistate Ferroelectric Diodes with High Electroresistance Based on van der Waals Heterostructures Some van der Waals (vdW) materials exhibit ferroelectricity, making them promising for novel nonvolatile memories (NVMs) such as ferroelectric diodes (FeDs). CuInP<sub>2</sub>S<sub>6</sub> (CIPS) is a well-known vdW ferroelectric that has been integrated with graphene for memory devices. Here we demonstrate FeDs with self-rectifying, hysteretic current-voltage characteristics based on vertical heterostructures of 10 nm thick CIPS and graphene. By using vdW indium-cobalt top electrodes and graphene bottom electrodes, we achieve a high electroresistance (on- and off-state resistance ratios) of ∼10<sup>6</sup>, an on-state rectification ratio of 2500 for read/write voltages of 2 V/0.5 V, and a maximum output current density of 100 A/cm<sup>2</sup>. These metrics compare favorably with state-of-the-art FeDs. Piezoresponse force microscopy measurements show that stabilization of intermediate net polarization states in CIPS leads to stable multibit data retention at room temperature. The combination of two-terminal design, multibit memory, and low-power operation in CIPS-based FeDs is potentially interesting for compute-in-memory and neuromorphic computing applications. Ferroelectricity ; Heterojunction ; van der Waals force ; Materials science ; Diode ; Optoelectronics ; Nanotechnology ; Dielectric ; Physics ; Quantum mechanics ; Molecule Ferroelectric and Piezoelectric Materials ; Electronic and Structural Properties of Oxides ; Inorganic Chemistry and Materials
Authors: Lan Wang | Jun Yan Dai | Ke Seng Ding | Hongxin Zeng | Qiang Cheng | Zi Qiang Yang | Yaxin Zhang | Tie Jun Cui
Source: Science Advances (article, 2024-11-22)
Field: Materials Science — Electronic, Optical and Magnetic Materials

High-order direct modulation terahertz communications with a wideband time-coding metachip modulator Terahertz communication technology based on on-off keying (OOK) direct modulation is vital for sixth-generation communication systems, especially in short-distance and high-rate applications. However, low-order OOK modulation often leads to suboptimal anti-interference capabilities and a heightened demodulation threshold. Here, we propose a high-order direct modulation terahertz communication framework using a wideband time-coding metachip modulator. The modulator leverages the electromagnetic resonance properties within the metaunit structure, with control enabled by gallium arsenide Schottky diodes. By manipulating the timing of voltage pulses applied to these diodes, the equivalent electromagnetic resonance distributions can be precisely regulated in the time domain. This enables independent and accurate control over the amplitude and phase of terahertz harmonics. Leveraging this technique, three high-order modulation schemes-quadrature phase-shift keying, 16-phase-shift keying, and 16-quadrature amplitude modulation- are achieved in a direct modulation and direct detection system, demonstrating the real-time image transmission. The proposed method offers an important way to develop integrated and low-complexity terahertz wireless communication systems. Quadrature amplitude modulation ; Amplitude modulation ; Keying ; Modulation (music) ; Pulse-amplitude modulation ; Electronic engineering ; Phase-shift keying ; Phase modulation ; Terahertz radiation ; Computer science ; Physics ; Telecommunications ; Optoelectronics ; Frequency modulation ; Radio frequency ; Engineering ; Bit error rate ; Phase noise ; Detector ; Decoding methods ; Acoustics Metamaterials and Metasurfaces Applications ; Terahertz technology and applications ; Energy Harvesting in Wireless Networks
Authors: Jichao Fu | Mengting Jiang | Zeng Wang | Yi Fan Chen | Yuanda Liu | Qing Yang Steve Wu | Ai Jia Sim | Jiang Wang | Mingxi Chen | Ziyu Wang | Jie Deng | Xiao Song Eric Tang | Kun Huang | Hong Liu | Jinghua Teng
Source: Opto-Electronic Science (article, 2024-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Supercritical metalens at h-line for high-resolution direct laser writing Supercritical lens (SCL) can break the diffraction limit in the far field and has been demonstrated for high-resolution scanning confocal imaging. Its capability in sharper focusing and needle-like long focal depth should allow high-resolution lithography at violet or ultraviolet (UV) wavelength, however, this has never been experimentally demonstrated. As a proof of concept, in this paper SCLs operating at 405 nm (h-line) wavelength with smaller full-width-at-half-maximum focal spot and longer depth of focus than conventional Fresnel zone lens while maintaining controlled side lobes are designed for direct laser writing (DLW) lithography. Aluminum nitride (AlN) with a high refractive index and low loss in UV-visible range is used to fabricate nanopillar-based metasurfaces structure for the metalens. Grating arrays with improved pitch resolution are fabricated using the SCLs with sub-diffraction-limit focusing capability. The AlN-based metasurface for SCLs at short wavelength for DLW could extend further to UV or deep UV lithography and might be of great interest to both the research and industry applications. Materials science ; Optics ; Lithography ; Extreme ultraviolet lithography ; Numerical aperture ; Lens (geology) ; Laser ; Wavelength ; Optoelectronics ; Focal length ; Diffraction ; Photolithography ; Resolution (logic) ; Nanopillar ; Photonics ; Nanotechnology ; Physics ; Nanostructure Metamaterials and Metasurfaces Applications ; Photonic Crystals and Applications ; Optical Coatings and Gratings
Authors: Mahmoud Hussein Hadwan | Abdulsamie H. Alta’ee | Rawa M. Mohammed | Asad M. Hadwan | Hawraa Saad Al‐Kawaz | Zainab Abbas Al Talebi
Source: Bulletin of the National Research Centre/Bulletin of the National Research Center (article, 2024-03-22)
Field: Chemistry — Analytical Chemistry

An efficient protocol for quantifying catalase activity in biological samples Abstract Background Catalase is an important enzyme that helps protect cells against oxidative stress. The current protocol presents a reliable method for measuring catalase (CAT) enzyme activity in biological systems using the CUPRAC-CAT method. Methods In the CUPRAC-CAT method, the component of the enzymatic reaction was incubated before adding the Cu(Nc) 2 2+ reagent. The unreacted substrates reduced the Cu(II)-the neocuproine complex, resulting in the highly colored Cu(I)-neocuproine product, which could be detected spectrophotometrically at 450 nm. The negative correlation between catalase activity and the absorbance of the Cu(I)-neocuproine complex was examined. To assess the optimization of Cu(I)-neocuproine complex production, response surface methodology (RSM) was employed, specifically utilizing the Box–Behnken design (BBD). Additionally, the reliability of the newly developed protocol was confirmed through Bland–Altman analysis of catalase activity in paired samples, employing the peroxovanadate method. Results The novel method is just as accurate as the established standard; the correlation between the two methods was 0.99. The CUPRAC-CAT method is stable, sensitive, linear, reproducible, accurate, and selective and can be used for quantifying oxidative stress while measuring catalase activity in liver tissue homogenates. Conclusions This study has demonstrated a straightforward and dependable protocol for evaluating catalase activity. The protocol is free from interference and can be easily employed in scientific research, ensuring a high level of accuracy and precision. The CUPRAC-CAT method is an effective technique to monitor bacterial contamination. This method provides quick and reliable results that can help ensure food safety and prevent or address bacterial contamination. Graphical abstract Catalase ; Protocol (science) ; Chemistry ; Computational biology ; Biology ; Computer science ; Biochemistry ; Enzyme ; Medicine Dye analysis and toxicity ; Protein Interaction Studies and Fluorescence Analysis ; Electrochemical sensors and biosensors
Authors: Keisuke Kanayama | Hisashi Nakamura | Kaoru Maruta | András Bödi | Patrick Hemberger
Source: Chemistry - A European Journal (article, 2024-06-15)
Field: Chemistry — Organic Chemistry

The Unimolecular Decomposition Mechanism of Trimethyl Phosphate Trimethyl phosphate (TMP), an organophosphorus compound (OPC), is a promising fire-retardant candidate for lithium-ion battery (LIB) electrolytes to mitigate fire spread. This study aims to understand the mechanism of TMP unimolecular thermal decomposition to support the integration of a TMP chemical kinetic model into a LIB electrolyte surrogate model. Reactive intermediates and products of TMP thermal decomposition were experimentally detected using vacuum ultraviolet (VUV) synchrotron radiation and double imaging photoelectron photoion coincidence (i<sup>2</sup>PEPICO) spectroscopy. Phosphorus-containing intermediates such as PO, HPO and HPO<sub>2</sub> were identified. Sampling effects could successfully be obviated thanks to photoion imaging, which also showed evidence for isomerization reactions upon wall collisions in the ionization chamber. Quantum chemical calculations performed for the unimolecular decomposition of TMP revealed for the first time that isomerization channels via hydrogen and methyl transfer (barrier heights of 65.9 and 72.6 kcal/mol, respectively) are the lowest-energy primary steps of TMP decomposition followed by CH<sub>3</sub>OH/CH<sub>3</sub>/CH<sub>2</sub>O or dimethyl ether (DME) production, respectively. We found an analogous DME production channel in the unimolecular decomposition of dimethyl methylphosphonate (DMMP), another important OPC fire-retardant additive with a similar molecular structure to TMP, which are not included in currently available chemical kinetic models. Decomposition ; Mechanism (biology) ; Chemistry ; Phosphate ; Organic chemistry ; Philosophy ; Epistemology Chemical Thermodynamics and Molecular Structure ; Chemical Reaction Mechanisms ; Free Radicals and Antioxidants
Authors: Geon‐Tae Park | Jae‐Hyun Kim | Seunghun Lee | Dong In Kim | Ki‐Seok An | Eungkyu Lee | Soonmin Yim‬ | Sun‐Kyung Kim
Source: Advanced Optical Materials (article, 2024-06-25)
Field: Materials Science — Surfaces, Coatings and Films

Conformal Antireflective Multilayers for High‐Numerical‐Aperture Deep‐Ultraviolet Lenses Abstract Precise surface reflectance control at specific deep‐ultraviolet (DUV) wavelengths across wide angles is crucial for semiconductor inspection and lithography tools. The inherent challenges in designing DUV antireflective multilayers stem from limited transparent materials and the resultant fabrication complexity owing to numerous interfaces. Here, wide‐angle antireflective multilayers finely tuned to 248 nm designed using an active learning scheme is presented. The active learning scheme employing factorization machines (FM) identifies the optimal configurations for binary‐material‐based multilayers (AlF 3 /LaF 3 , AlF 3 /MgF 2 , and AlF 3 /Al 2 O 3 ) with varying index contrasts, achieving minimal figure‐of‐merit (i.e., average angular reflectance) values at predetermined total thicknesses. High‐index‐contrast AlF 3 /Al 2 O 3 multilayers are fabricated via atomic layer deposition, thus enabling the conformal coating of high‐numerical‐aperture (NA) lenses with atomic precision. An optimized AlF 3 /Al 2 O 3 tri‐layer with a total thickness of 180 nm results in an average (0°–45°) reflectance of 0.4% on a CaF 2 planar substrate and 0.6% on a CaF 2 convex lens (NA = 0.47), similar to the performance of an ideal single‐layer coating requiring a practically unavailable refractive index. Phasor analysis, which considers only first‐order reflections between adjacent layers, supports the benefits of high‐index‐contrast binary materials and the use of the FM‐based active learning scheme in antireflective multilayer design. Anti-reflective coating ; Materials science ; Ultraviolet ; Optics ; Conformal map ; Numerical aperture ; Optoelectronics ; Nanotechnology ; Wavelength ; Physics ; Geometry Optical Coatings and Gratings ; Advanced optical system design ; Photonic and Optical Devices
Authors: Aditi Mahajan | Sandeep Gairola | Inderdeep Singh | Navneet Arora
Source: Polymer Composites (article, 2024-04-30)
Field: Materials Science — Polymers and Plastics

Optimized random forest model for predicting flexural properties of sustainable composites Abstract In an era of technological advancements, the quest for sustainable products has taken a center stage. The utilization of natural fiber reinforced polymer composites has become crucial in the manufacturing of eco‐friendly products due to their low cost, renewability, biodegradability, and comparable properties to synthetic composites. Coir‐based composites have been utilized in roofing, composite panels, furniture, and bio‐based insulation applications, providing enhanced strength and sustainability. In the current investigation, an exploratory data analysis (EDA) was conducted to understand the relationship between the various input variables and the flexural properties of short coir polymer composites (SCPCs). The data analysis revealed that manufacturing process had a significant impact on the flexural properties of SCPCs. Based on the insights gained from the EDA, an optimized Random Forest prediction model was developed to predict the flexural properties. Genetic algorithm approach for hyperparameter optimization led to lower objective loss in contrast to Bayesian optimized Random Forest model. The model's performance was subsequently evaluated through holdout validation, and the outcome demonstrated the model's proficiency in accurately predicting the properties. The developed model can be used as a tool for optimizing the design of SCPCs for specific applications, by predicting the flexural properties of the composites. Highlights Flexural behavior of short coir polymer composites was analyzed and modeled. Manufacturing process has the highest impact on the flexural properties. Random forest model predicted the flexural properties with high accuracy. Genetic algorithm optimized model further enhanced the model performance. The developed framework provides insights into designing biocomposites. Flexural strength ; Materials science ; Composite material ; Random forest ; Coir ; Computer science ; Machine learning Natural Fiber Reinforced Composites ; Mechanical Behavior of Composites ; Additive Manufacturing and 3D Printing Technologies
Authors: Oğuzhan Akin | Qing He | Parviz Yazdani | Yihan Wang | Robin John Varghese | Hilde Poelman | Paul Van Steenberge | Kevin M. Van Geem
Source: Journal of Analytical and Applied Pyrolysis (article, 2024-06-19)
Field: Chemistry — Inorganic Chemistry

Tailored HZSM-5 catalyst modification via phosphorus impregnation and mesopore introduction for selective catalytic conversion of polypropylene into light olefins Catalysis ; Mesoporous material ; Polypropylene ; Pyrolysis ; Phosphorus ; Chemical engineering ; Materials science ; Chemistry ; Organic chemistry Zeolite Catalysis and Synthesis ; Chemical Synthesis and Characterization ; Catalysis and Hydrodesulfurization Studies
Authors: Enzo Isnard | Sébastien Héron | Stéphane Lanteri | Mahmoud Elsawy
Source: Scientific Reports (article, 2024-01-18)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Advancing wavefront shaping with resonant nonlocal metasurfaces: beyond the limitations of lookup tables Resonant metasurfaces are of paramount importance in addressing the growing demand for reduced thickness and complexity, while ensuring high optical efficiency. This becomes particularly crucial in overcoming fabrication challenges associated with high aspect ratio structures, thereby enabling seamless integration of metasurfaces with electronic components at an advanced level. However, traditional design approaches relying on lookup tables and local field approximations often fail to achieve optimal performance, especially for nonlocal resonant metasurfaces. In this study, we investigate the use of statistical learning optimization techniques for nonlocal resonant metasurfaces, with a specific emphasis on the role of near-field coupling in wavefront shaping beyond single unit cell simulations. Our study achieves significant advancements in the design theoretical conception of resonant metasurfaces. For transmission-based metasurfaces, a beam steering design outperforms the classical design by achieving an impressive efficiency of 80% compared to the previous 23%. Additionally, our optimized extended depth-of-focus (EDOF) metalens yields a remarkable five-fold increase in focal depth, a four-fold enhancement in focusing power compared to conventional designs and an optical resolution superior to 600 cycle/mm across the focus region. Moreover, our study demonstrates remarkable performance with a wavelength-selected beam steering metagrating in reflection, achieving exceptional efficiency surpassing 85%. This far outperforms classical gradient phase distribution approaches, emphasizing the immense potential for groundbreaking applications in the field of resonant metasurfaces. Wavefront ; Lookup table ; Computer science ; Physics ; Optics Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies ; Antenna Design and Analysis