jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Ping Wang | Yu‐Jong Wu | Hong Si Wu
Source: Journal of Student Research (article, 2023-02-28)
Field: Materials Science — Materials Chemistry

Spectroscopic Investigation on Liquid-exfoliated Hexagonal Boron Nitride Nano Particles Although hexagonal boron nitride and graphene in two-dimensional materials have similar structures, there are great differences in their electronic structures. hBN has a huge energy gap (~ 6 eV) and can be regarded as a semiconductor or insulator, while graphene can be used as a conductor because of its zero-energy gap. Because of their high degree of lattice matching, they often overlap each other and are used as conductive layer and insulating layer in the material process of electronic components. In this study, we tried to prepare nano-sized hexagonal boron nitride particles by a relatively simple method "liquid-assisted ball milling and ultrasonic exfoliating" to solve the high-cost problem of the industrialization of hBN. We prepared hBN nanoparticles using zirconium milling balls, water-proof sonication and ultrasonic crusher, then studied the essential changes to their electronic structures and sizes through Atomic Force Microscope and various spectroscopic methods such as PL, PLE, absorption and Raman spectrum. It helps us to find ways to control the electronic structure and energy gap of hBN, which would help the development of advanced semiconductor manufacturing applications and advanced quantum light sources. Materials science ; Boron nitride ; Semiconductor ; Raman spectroscopy ; Band gap ; Graphene ; Nanotechnology ; Nano- ; Optoelectronics ; Composite material ; Optics Graphene research and applications ; Diamond and Carbon-based Materials Research ; Boron and Carbon Nanomaterials Research
Authors: E.A. Ryabkova | L.A. Sokura | A.Yu. Ivanov | I.M. Sosnin | A.V. Kremleva | M. V. Dorogov
Source: Reviews on advanced materials and technologies (article, 2023-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Effect of Solution Composition on the Morphology of Synthesized β-Ga2O3 Particles Micro- and nanoparticles of β-Ga2O3 are synthesized as a result of chemical reaction of an aqueous solution of gallium nitrate and various alkalis: ammonia, sodium, potassium, and lithium hydroxides. It is shown that particles morphology depends on the type and concentration of alkali. The use of microwave treatment of ammonia containing solutions made it possible to change the shape of particles from ellipsoidal to parallelepiped while maintaining their size. In contrast to the synthesis with ammonia, for other alkalis dispersed particles were obtained only at a ratio of alkali to gallium nitrate equal to 3, and these particles did not belong to the gallium oxide β-phase. Alkali metal ; Gallium ; Inorganic chemistry ; Ammonia ; Aqueous solution ; Particle size ; Potassium nitrate ; Morphology (biology) ; Potassium ; Chemistry ; Lithium (medication) ; Particle (ecology) ; Chemical engineering ; Materials science ; Organic chemistry ; Physical chemistry Ga2O3 and related materials ; Advanced Photocatalysis Techniques ; ZnO doping and properties
Authors: Sally Howells-Wyllie | Mike Andrews | Michelle Canning | Emily Cuffin-Munday | Eva Balentova | Susannah Davies | Debora Giovanelli | Helen Lunn | Samuel Oldknow | Kate Tustain | Daphne Houston | Huw Hedges | Jeanne Andres | Jean-Franois Grard | Yutaka Amao | Annie Castonguay | Alexander Cobb | Vera Constantino | Catharine Esterhuysen | Yannick Guari | Suman Jain | Peter Junk | Venkata Krishnan | Karine Philippot | Luca Prodi | Akhila Sahoo | Jianji Wang | Gregory Welch | Kazunari Yoshizawa | Odile Eisenstein | Miaohui Yu | Tingting Fu | Wenzhai Li | Yan Zhang | Huayan Wen | Min Zheng | Moran Shi | Caiyun Liu | Meng Jin | Kechun Liu | Lei Cai | Baocun Zhu | Wenlong Sheng | Cobalt Coordinated | Qianhui Ma | Shuang Zheng | Jiajie Wang | Chenghang You | Xianghui Wang | Qingqing Wang | Weiping Wang | Fengxiao Li | Jiaqi Fan | Shuo Gan | Jiaming Zhang | Qikun Jiang | Tianhong Zhang | Tao Liu | Tingting Jiang | Jinqi Zhu | Tingwei Rui | Shourong Zheng | Zhixin Hu | Purashri Basyach | Siddhartha Purkayastha | Ankur Guha | Parasa Hazarika | * | Lakshi Saikia ; Yuan Pan | Haixin Song | Hui Jiang | * Yujing Guo | Linlin Shi | Lingling Guo | Aihong Wu | Chuanlai | Jinsong Gong | Xiaobin Li | Shaoping Li | Man Xu | Wubin Dai | ; Liu | Hao Sun | Yuhai Li | Xueshi Xu | Peng Zhang
Source: New Journal of Chemistry (article, 2023-01-01)
Field: Chemistry — Inorganic Chemistry

Contents list Permissions Request permissions Contents list New J. Chem., 2023, 47, 22021 DOI: 10.1039/D3NJ90187D This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given. Read more about how to correctly acknowledge RSC content. Chemistry ; Acknowledgement ; Chromatin structure remodeling (RSC) complex ; Attribution ; Library science ; World Wide Web ; Computer security ; Computer science ; Psychology Radioactive element chemistry and processing
Authors: Subhajit Saha | Sudipta Khamurai | Rajib Moi | Anakuthil Anoop | Владимир В. Чернышев | Debamalya Banerjee | Kumar Biradha
Source: ChemRxiv (preprint, 2023-05-08)
Field: Materials Science — Materials Chemistry

Photochromism and Photomagnetism in 1,4-bis(4,5-diphenyl-imidazolyl)benzene Chromophores: Water Assisted π-stacks for the Generation of Stable Free Radicals in Solid State Photochromism and photomagnetism are two important features for the generation of smart materials that are of utility for optical switches and memory devices. Very few materials that exhibit both the features at room temperature are known to date, the reported ones mostly contain metal-ions to assist the electron transfer with photo stimuli. Herein, we report a new class of organic materials that show photochromism and photomagnetism at room temperature due to the generation of free radicals in the solid-state. 1,4-bis(4,5-diphenyl-1H-imidazol-2-yl)benzene (BDPI) was found to acts as organic photomagnet without use of any traditional photochromic couplers or radical containing moieties. Solvent molecules (eg. water and DMSO) form hydrogen bonds with the imidazole rings which act as binding glue in stacking of 1,4-bis(imidazolyl)benzene moieties via π···π interactions. These interactions found to play a significant role in promoting strong spin-spin interaction in the solid-state which can be inferred from the appearance of broad EPR signal, whereas a sharp signal appeared only after irradiation. The sharp signal indicates formation of paramagnetic free radicals which influence antiferromagnetic exchange interactions with weakening of the magnetic susceptibility significantly. This work provides a new direction in the ongoing research of photochromic and photomagnetic materials, where a simple 1,4- bis(imidazolyl)benzene system changes its color, radical activity and magnetic behavior with photoirradiation. Photochromism ; Radical ; Photochemistry ; Chromophore ; Electron paramagnetic resonance ; Antiferromagnetism ; Stacking ; Chemistry ; Benzene ; Hydrogen bond ; Molecule ; Organic chemistry ; Nuclear magnetic resonance Photochromic and Fluorescence Chemistry ; Radical Photochemical Reactions ; Luminescence and Fluorescent Materials
Authors: Denis Karpov | Р. В. Борисов | Maxim Likhatski | С. В. Сайкова
Source:  (article, 2023-01-01)
Field: Materials Science — Materials Chemistry

X-RAY STRUCTURAL STUDIES OF SYNTHETIC VALLERIITES USING SYNCHROTRON RADIATION Valleriite is a rare mineral of the hydroxysulfide group, that structure and physicochemical properties are atypical for sulfides. The first attempts to identify the structure of valleriite led to false conclusion of its purely sulfide nature, while the magnesium and aluminum present in the samples were attributed to the contamination of natural samples with associated minerals (brucite, lizardite and others). Nevertheless, through the number of works of domestic and foreign authors, the structure of natural valleriite was determined, as well as of a number of new minerals of the valleriite group - tochilinite, haapalaite, yushkinite and others. Brucite ; Mineral ; Synchrotron radiation ; Magnesium ; Natural mineral ; Materials science ; Mineralogy ; Chemistry ; Metallurgy ; Physics ; Optics Thermal and Kinetic Analysis ; X-ray Diffraction in Crystallography ; Metal Extraction and Bioleaching
Authors: Kahkasha Parveen | Srimanta Pakhira
Source: arXiv (Cornell University) (preprint, 2023-07-10)
Field: Chemistry — Inorganic Chemistry

Designing of Organic Bridging Linkers of Metal-Organic Frameworks for Enhanced Carbon Dioxide Adsorption The global rate of anthropogenic CO2 emission is rising, which urges the development of efficient carbon capture and storage (CCS) technologies. Among the various CO2 capture methods, adsorption by the linkers of the Metal-Organic Frameworks (MOFs) materials has received more interest as excellent CO2 adsorbents because of their important role in understanding the interaction mechanism for CO2 adsorption. Here, we investigate the adsorption of CO2 molecules at the center and side positions of several MOF-linkers using molecular cluster models. The interaction between CO2 and the linkers is approximated by computing the binding enthalpy (ΔH) through the first principles-based Density Functional Theory with Grimmes dispersion correction (i.e., B3LYP-D3) and second-order Moller Plesset Theory (MP2). The computed values of ΔH indicate the weak nature of CO2 adsorption on the pristine linkers, hence the strategy of lithium decoration is used to see its impact on the binding strength. Among the various linkers tested, CO2 adsorbing at the side position of the DFBDC-2 linker has strong adsorption with ΔH value of about -35.32 kJ/mol computed by the B3LYP-D3 method. The Energy Decomposition Analysis (EDA) study reveals that among all the energy terms, the contribution of electrostatic and polarization energy terms to the ΔH value are the most dominant one. Furthermore, the results of Frontier Molecular Orbital Analysis (FMO) revealed that all the linkers remained stable even after Li-decoration. The results of our investigations will direct towards the development and synthesis of novel adsorbents with enhanced CO2 adsorption. Adsorption ; Density functional theory ; Binding energy ; Dendrimer ; Metal-organic framework ; Molecule ; Materials science ; Computational chemistry ; Linker ; Chemistry ; Chemical physics ; Physical chemistry ; Nanotechnology ; Organic chemistry ; Polymer chemistry ; Physics ; Computer science ; Atomic physics Metal-Organic Frameworks: Synthesis and Applications ; Carbon Dioxide Capture Technologies ; Phase Equilibria and Thermodynamics
Authors: Dasrao A. Patil | Sanjay K. Bais | Ajit Gorakh Chaudhari
Source: International Journal of Advanced Research in Science Communication and Technology (article, 2023-01-27)
Field: Chemistry — Analytical Chemistry

Modern Herbal Technology People are growing more interested in herbal medicines today because of their numerous advantages. Herbal formulations are now widely recognised as successful therapies for a variety of diseases. More than 80% of people throughout the world utilise herbal items and drugs to maintain a healthy lifestyle, even though the majority of these applications are unusual. A number of product abuses and adulterations have also been brought on by the rising use of herbal products, disappointing consumers and manufacturers and, in some cases, having disastrous outcomes. The development of trustworthy analytical methods that can quantitatively analyse marker/bioactive compounds, other essential elements, and accurately profile the phytochemical composition is extremely challenging for scientists. Standardization is a key step in creating a uniform biological activity, consistent chemical profile, or even merely a quality assurance programme for the production and manufacturing of herbal medicines. The current review article describes various conventional methods as well as more recent developments. In fields including DNA fingerprinting, metabolomics, differential pulse polarography, chemometrics, X-ray diffraction, and others, recent advancements have been noticed. The standardisation of herbal remedies benefits from chromatographic and capillary electrophoresis techniques are also described. Objective: 1. Recognize the origin of herbal drugs in their raw materials, from their cultivation to their finished products. 2. Be familiar with the WHO and ICH guidelines for evaluating herbal medications. 3. Understand natural sweeteners, nutraceuticals, and herbal cosmetics 4. Value GMP and the patenting of herbal remedies Nutraceutical ; Traditional medicine ; Medicine ; Cosmetics ; Standardization ; Risk analysis (engineering) ; Business ; Biotechnology ; Computer science ; Biology Heavy Metals in Plants ; Analytical Chemistry and Chromatography ; Analytical Methods in Pharmaceuticals
Authors: Daniel Rozsar | Alistair J. M. Farley | Iain McLauchlan | Benjamin D. A. Shennan | Ken Yamazaki | Darren J. Dixon
Source: Angewandte Chemie (article, 2023-03-16)
Field: Chemistry — Organic Chemistry

Bifunctional Iminophosphorane‐Catalyzed Enantioselective Nitroalkane Addition to Unactivated α,β‐Unsaturated Esters** Abstract Herein we describe the enantioselective intermolecular conjugate addition of nitroalkanes to unactivated α,β‐unsaturated esters, catalyzed by a bifunctional iminophosphorane (BIMP) superbase. The transformation provides the most direct access to pharmaceutically relevant enantioenriched γ‐nitroesters, utilizing feedstock chemicals, with unprecedented selectivity. The methodology exhibits a broad substrate scope, including β‐(fluoro)alkyl, aryl and heteroaryl substituted electrophiles, and was successfully applied on a gram scale with reduced catalyst loading, and, additionally, catalyst recovery was carried out. The formal synthesis of a range of drug molecules, and an enantioselective synthesis of ( S )‐rolipram were achieved. Additionally, computational studies revealed key reaction intermediates and transition state structures, and provided rationale for high enantioselectivities, in good agreement with experimental results. Enantioselective synthesis ; Bifunctional ; Chemistry ; Electrophile ; Catalysis ; Aryl ; Combinatorial chemistry ; Organocatalysis ; Substrate (aquarium) ; Organic chemistry ; Alkyl ; Bifunctional catalyst Asymmetric Synthesis and Catalysis ; Asymmetric Hydrogenation and Catalysis ; Synthesis and Catalytic Reactions
Authors: Liujia Min | Aigen Li | Xianghong Chen | Yonghui Li
Source: arXiv (Cornell University) (preprint, 2023-10-28)
Field: Chemistry — Organic Chemistry

Simulations of the Visible, Infrared and Terahertz Properties of Doped Cyclo[18]carbon Molecules Using Tuned Exchange-Correlation Potential Cyclocarbon molecules are critical in understanding the carbon structure formation and the nature of the interaction between carbon atoms. In cyclocarbons, light elements such as H, O and N may interplay with rings to form doped cyclocarbon molecules. Such molecules show unique optical properties that have never been reported before. In this study, density functional theory with a tuned PBE functional (39% HF exchange) is employed to study the ground and excited states of a cyclo[18] carbon molecule (C18) and its doped variants C18M (M = H, Be, B, N, and O). The doping is shown to either make the UV-Vis spectra of C18 blue- or red-shifted depending on the spin brought by the dopant. Furthermore, introducing extra-atoms is found to cause the emergence of a new set of infrared modes in the structure under investigation. Finally, applying the molecular dynamic simulations enables one to observe the terahertz characteristics of C18M with frequencies up to 1.5 THz due to the propagation of a particular pattern along the carbon ring. Terahertz radiation ; Molecule ; Doping ; Infrared ; Carbon fibers ; Excited state ; Density functional theory ; Dopant ; Materials science ; Ring (chemistry) ; Infrared spectroscopy ; Molecular physics ; Chemical physics ; Chemistry ; Computational chemistry ; Atomic physics ; Optoelectronics ; Physics ; Optics ; Organic chemistry Synthesis and Properties of Aromatic Compounds ; Advanced Chemical Physics Studies ; Molecular Junctions and Nanostructures
Authors: Zuzanna M. Jedlinska | Robert A. Riggleman
Source: arXiv (Cornell University) (preprint, 2023-12-14)
Field: Materials Science — Materials Chemistry

The effects of dynamic binding on the phase behaviour and properties of polymer blends undergoing complex coacervation Associative polymer networks have shown a major promise in fabrication of self-healing and responsive materials. The can also serve as simple models to study more complex biological systems where transient interactions play an important role. In this work we investigate the properties of charged polymer blends whose constituents are capable of creating dynamic bonds. We model dynamic bonds as harmonic springs with additional bond formation energy, $\varepsilon_a$, which can be adjusted to influence the reaction rates for binding and unbinding. We show that varying the number of binding sites on the chains and $\varepsilon_a$ has a major effect on the resulting phase diagram. We further investigate the diffusive behaviour of the coacervates. We also study, how the network structure changes with varying number of active site, and increasing $\varepsilon_a$, and identify the values which result in the network percolation. Lastly, we explore the possibility of inducing orthogonal phase separation by by introducing a second type of binding site, which cannot interact with the first kind. Coacervate ; Phase diagram ; Percolation (cognitive psychology) ; Polymer ; Chemical physics ; Phase (matter) ; Work (physics) ; Materials science ; Binding energy ; Transient (computer programming) ; Statistical physics ; Biological system ; Chemistry ; Thermodynamics ; Physics ; Computer science ; Organic chemistry ; Composite material ; Chromatography ; Quantum mechanics Pickering emulsions and particle stabilization ; Proteins in Food Systems ; Material Dynamics and Properties
Authors: Hiroki Muraoka | Satoshi Ogawa
Source: Heterocycles (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

1,3,5-Triazine-Cored Star-Shaped (D-π)3-A Molecules Based on 2,4,6-Tris(5-arylthiophen-2-yl)-1,3,5-triazine Star-shaped (D-)3-A molecules consist of three parts: an electron-accepting core (A), -conjugated bridges (), and electron-donating terminals (D).These molecules are commonly designed using a (thiophene)3-A (1,3,5-triazine) segment composed of 2,4,6-tri(thiophen-2-yl)-1,3,5-triazine (TTT), which offers geometric and electronic structural advantages.By structurally and electronically modifying TTT with different types of electron-donating aryl terminals, we systematically construct TTT-based star-shaped (D-)3-A molecules with controlled molecular properties attributed to a special structure in which the star-shaped and D--A structures are hybridized.This review summarizes our researches on the synthesis, optical and electronic characterization, and application of a series of 2,4,6-tris(5-arylthiophen-2-yl)-1,3,5-triazines based on our concept.CONTENTS 1. Introduction 2. Synthesis, characterization, and application of a series of 2,4,6-tris(5-arylthiophen-2-yl)-1,3,5-triazines (TATTs) 2-1.Systematic synthesis of TATTs 2-2.Optical and electronic properties of TATTs 2-3.Optical sensing responses of TATTs to solvent polarity 2-4.Optical sensing responses of TATTs to protons 2-5.Optical sensing responses of TATTs to metal ions 3. Conclusion 1. Triazine ; Molecule ; Chemistry ; Thiophene ; Tris ; Star (game theory) ; Characterization (materials science) ; Crystallography ; Polymer chemistry ; Nanotechnology ; Materials science ; Organic chemistry ; Physics Synthesis and Characterization of Heterocyclic Compounds ; Luminescence and Fluorescent Materials ; Porphyrin and Phthalocyanine Chemistry
Authors: Harley Quinn | Wenlu Wang | Jörg G. Werner | Keith A. Brown
Source: arXiv (Cornell University) (preprint, 2023-03-27)
Field: Chemistry — Electrochemistry

Screening for electrically conductive defects in thin functional films using electrochemiluminescence Multifunctional thin films in energy-related devices often must be electrically insulating where a single nanoscale defect can result in complete device-scale failure. Locating and characterizing such defects presents a fundamental problem where high-resolution imaging methods are needed to find defects, but imaging with high spatial resolution limits the field of view and thus the measurement throughput. Here, we present a novel high-throughput method for detecting sub-micron defects in insulating thin films by leveraging the electrochemiluminescence (ECL) of luminol. Through a systematic study of reagent concentrations, buffers, voltage, and excitation time, we identify optimized conditions at which it is possible to detect features with areas ~500 times smaller than the area interrogated by a single pixel of the camera, showing high-throughput detection of sub-micron defects. In particular, we estimate the minimum detectable features to be lines as narrow as 2.5 nm in width and pinholes as small as 35 nm in radius. We further explore this method by using it to characterize a nominally insulating phenol film and find conductive defects that are cross-correlated with high-resolution atomic force microscopy to provide feedback to synthesis. Given the inherent parallelizability and scalability of this assay, it is expected to have a major impact on the automated discovery of multifunctional films. Electrochemiluminescence ; Materials science ; Throughput ; Nanoscopic scale ; Thin film ; Optoelectronics ; Electrical conductor ; Resolution (logic) ; Image resolution ; Scalability ; Conductive atomic force microscopy ; Nanotechnology ; Voltage ; Pixel ; Electrode ; Computer science ; Atomic force microscopy ; Electrical engineering ; Wireless ; Composite material ; Physics ; Artificial intelligence Electrochemical Analysis and Applications ; Advanced biosensing and bioanalysis techniques ; Force Microscopy Techniques and Applications
Authors: Mehmet Pişkin | Zafer Odabaş | Mahmut Durmuş
Source: Afyon Kocatepe University Journal of Sciences and Engineering (article, 2023-06-22)
Field: Materials Science — Materials Chemistry

Synthesis and Spectroscopic Properties of Newly Tetrapyrazinoporphyrazine Containing Gadolinium(III) Acetate A new tetrakis-(2-methylpyrazino)porphyrazinato gadolinium(III) acetate complex was synthesized. Elemental analysis, Fourier-Transform Infrared, Ultraviolet-visible, and fluorescence spectroscopy techniques clarified its structure. It can dissolve very well without aggregation in both Dimethyl sulfoxide and N, N-Dimethylformamide, which have high dielectric constant and high dipole moment from polar aprotic solvent type. Its aggregation property was also investigated in dimethyl sulfoxide at different concentrations, and it was determined to contain monomeric species. In addition, its fluorescence properties were investigated in Dimethyl sulfoxide and the effect of gadolinium(III) acetate metal ion as a heavy rare earth element was determined. According to the findings in this study, it may be used as an electronic and optical material and in various technological applications such as photocatalytic applications. In addition, these findings may be useful for systems that include changes in pyrazinoporphyrazine-like forms. Dimethyl sulfoxide ; Dimethylformamide ; Chemistry ; Fluorescence ; Sulfoxide ; Solvent ; Monomer ; Fourier transform infrared spectroscopy ; Photochemistry ; Nuclear chemistry ; Polymer chemistry ; Organic chemistry ; Polymer Porphyrin and Phthalocyanine Chemistry ; Photodynamic Therapy Research Studies ; Analytical Chemistry and Sensors