jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Zahra Amiri Rigi Mansoor Kazemimoghadam
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2022-12-20)
Field: Chemistry — Inorganic Chemistry

Synthesis, Evaluation, Modeling and Simulation of Nano-Pore NAA Zeolite Membranes Zeolite membranes have uniform and molecular-sized pores that separate molecules based on the differences in the molecules’ adsorption and diffusion properties. Strong electrostatic interaction between ionic sites and water molecules (due to its highly polar nature) makes the zeolite NaA membrane very hydrophilic. Zeolite NaA membranes are thus well suited for the separation of liquid-phase mixtures by pervaporation. In this study, experiments were conducted with various Ethanol–water mixtures (1–20 wt. %) at 25 °C. Total flux for Ethanol–water mixtures was found to vary from 0.331 to 0.229 kg/m2 .h with increasing Ethanol concentration from 1 to 20 wt.%. Ionic sites of the NaA zeolite matrix play a very important role in water transport through the membrane. These sites act both as water sorption and transport sites. Surface diffusion of water occurs in an activated fashion through these sites Zeolite ; Membrane ; Nano- ; Chemical engineering ; Materials science ; Chemistry ; Engineering ; Organic chemistry ; Biochemistry Zeolite Catalysis and Synthesis ; Quantum-Dot Cellular Automata
Authors: Maâzou SIRAGI D. B. | Halidou I. HIMA | Grégory PLOEGAERTS | Ousmaila SANDA MAMANE | Vincent DUBOIS | Ibrahim Natatou
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2022-09-30)
Field: Chemistry — Organic Chemistry

Modelling of the kinetics adsorption of gold (I) cyanide complex ion by active carbons prepared from Parinari macrophylla shells Nowadays, one of the sectors to valorization of waste is their transformation in nobler materials rather than in energy. This study is about the valorization of agricultural waste (<em>Parinari Macrophylla </em>shells) for the development of active carbons, the characterization of porous materials gotten and the kinetic study for adsorption of gold (I) cyanide complex ion. The development is made by impregnation in KOH followed of a pyrolysis under flux of N<sub>2 </sub>or CO<sub>2</sub>. The characteristics determined for adsorption are iodine index, methylene blue index, pH to point of zero charge (pH<sub>PZC</sub>) as well as the textures characteristics gotten by adsorption of nitrogen at 77 K. For adsorption of gold (I) cyanide complex ion , the kinetics model’s pseudo-order 1, pseudo-order 2, the model of Elovich and those diffusions of Boyd and Weber-Morris are studied. The results of the characterization showed that samples are basic (pH<sub>PZC</sub> &gt; 7), present the specific surfaces of 1008 m<sup>2</sup>/g and 1063 m<sup>2</sup>/g with percentages in microporous surface more than 78% and for microporous volume more than 71%. The kinetics of adsorption of gold (I) cyanide complex ion (Au(CN)<sub>2</sub><sup>-</sup>) obeys more to pseudo-order 2 model and a multi-linearity of the models of Elovich and diffusions during adsorption. Adsorption ; Cyanide ; Chemistry ; Kinetics ; Ion ; Active carbon ; Inorganic chemistry ; Nuclear chemistry ; Chemical engineering ; Organic chemistry ; Waste management ; Physics ; Engineering Inorganic and Organometallic Chemistry
Authors: Chinmayee Choudhury | Vivek Kumar
Source: ChemRxiv (preprint, 2022-04-13)
Field: Chemistry — Organic Chemistry

smProdrugs: A repository of small molecule prodrugs In modern drug discovery and development, the prodrug approach has become a crucial strategy for enhancing the pharmacokinetic profiles of drugs. A prodrug is a chemical compound, which gets metabolized into a pharmacologically active form (drug) inside the body after its administration. In the current work, we report ‘smProdrugs’, which is one of the first exclusive databases on small molecule prodrugs, which stores the structures, physicochemical properties and experimental ADMET data manually curated from literature. SmProdrugs lists 626 small molecule prodrugs and their active compounds with the above mentioned experimental data from 1808 research articles and 61 patents have been stored. The information page of each record gives the structures and properties of the prodrug and the active drug side by side which makes it easy for the user to instantly compare them. The structural modifications in the prodrug/active drugs are highlighted in a different colour for easy comparison. Experimental data has been curated from the downloaded PubMed and patent articles and were catalogued in a tabular form with more than 25 fields under sub-sections i) name and structures of the prodrugs and their active compounds, ii) mode of activation of the prodrug and enzyme/biocatalyst involved in the conversion, iii) indications/disease, iv) pharmacological target, v) experimental pharmacokinetic properties such as solubility, absorption, volume of distribution, half-life, clearance etc. and vi) information on the purpose/gain from the prodrug strategies. Considering the ever expanding utility of the prodrug approach smProdrugs will be of great use to the scientific community working on rational design of small molecule prodrugs. Prodrug ; Small molecule ; Drug ; Chemistry ; Drug discovery ; Rational design ; Combinatorial chemistry ; Active compound ; Pharmacokinetics ; Pharmacology ; Computational biology ; Computer science ; Nanotechnology ; Medicine ; Biochemistry ; Materials science ; Biology Click Chemistry and Applications ; Cyclopropane Reaction Mechanisms ; Biochemical Acid Research Studies
Authors: Weicheng Cao | Zhenfeng Pang | Xiaoqi Zhou | Zhenming Cao | Jiachen Li | Qi Wang | Xiaogang Peng | Xueqian Kong
Source: ChemRxiv (preprint, 2022-06-13)
Field: Chemistry — Spectroscopy

Calibrate Ligand-ligand Interaction on Nanocrystals via the Dynamic Volume of Chain Segments The intermolecular ligand-ligand interaction is crucial for the surface chemistry, solution properties, and self-assembly processes of colloidal nanocrystals (NCs). The studies on the ligand-ligand interaction are hampered by the disordered and dynamic nature of the surface, the low electron contrast of organic moieties, and the non-characteristic weak intermolecular forces. Solid-state nuclear magnetic resonance (NMR) can provide site-specific information on organic ligands and especially the motional behavior of chain segments. In this work, we develop an advanced solid-state NMR measurement and modelling strategy to quantify the “dynamic volume” of chain segments. The dynamic volume depicts the accessible space of a chain segment under the confinement of neighboring molecules, and is inversely proportional to the intermolecular interaction energy. The ligand-ligand interaction energies have been obtained for NCs with alkanoate ligands of different lengths. We show that the calculated ligand-ligand interaction energy determines solution dispersity and the melting transitions of NCs. This dynamic volume concept can be extended beyond experimental NMR measurements and offer semi-empirical predictions of the interaction energies for arbitrary selections of alkanoate ligands. Our study not only advances the quantitative understanding of ligand-ligand interaction on NCs but also establishes novel tactics to calibrate weak intermolecular interactions. Ligand (biochemistry) ; Intermolecular force ; Chemical physics ; Chemistry ; Interaction energy ; Molecule ; Dispersity ; Resonance (particle physics) ; Crystallography ; Computational chemistry ; Physics ; Atomic physics ; Organic chemistry Advanced NMR Techniques and Applications ; NMR spectroscopy and applications ; Advanced Neuroimaging Techniques and Applications
Authors: Weicheng Cao | Zhenfeng Pang | Xiaoqi Zhou | Zhenming Cao | Jiachen Li | Qi Wang | Xiaogang Peng | Xueqian Kong
Source: ChemRxiv (preprint, 2022-04-26)
Field: Chemistry — Spectroscopy

Calibrate Ligand-ligand Interaction on Nanocrystals via the Dynamic Volume of Chain Segments The intermolecular ligand-ligand interaction is crucial for the surface chemistry, solution properties, and self-assembly processes of colloidal nanocrystals (NCs). The studies on the ligand-ligand interaction are hampered by the disordered and dynamic nature of the surface, the low electron contrast of organic moieties, and the non-characteristic weak intermolecular forces. Solid-state nuclear magnetic resonance (NMR) can provide site-specific information on organic ligands and especially the motional behavior of chain segments. In this work, we develop an advanced solid-state NMR measurement and modelling strategy to quantify the “dynamic volume” of chain segments. The dynamic volume depicts the accessible space of a chain segment under the confinement of neighboring molecules, and is inversely proportional to the intermolecular interaction energy. The ligand-ligand interaction energies have been obtained for NCs with alkanoate ligands of different lengths. We show that the calculated ligand-ligand interaction energy determines solution dispersity and the melting transitions of NCs. This dynamic volume concept can be extended beyond experimental NMR measurements and offer semi-empirical predictions of the interaction energies for arbitrary selections of alkanoate ligands. Our study not only advances the quantitative understanding of ligand-ligand interaction on NCs but also establishes novel tactics to calibrate weak intermolecular interactions. Ligand (biochemistry) ; Intermolecular force ; Chemistry ; Chemical physics ; Interaction energy ; Dispersity ; Molecule ; Resonance (particle physics) ; Crystallography ; Computational chemistry ; Physics ; Atomic physics ; Polymer chemistry ; Organic chemistry Advanced NMR Techniques and Applications ; NMR spectroscopy and applications ; Advanced Neuroimaging Techniques and Applications
Authors: Weicheng Cao | Zhenfeng Pang | Xiaoqi Zhou | Zhenming Cao | Jiachen Li | Qi Wang | Xiaogang Peng | Xueqian Kong
Source: ChemRxiv (preprint, 2022-04-26)
Field: Chemistry — Spectroscopy

Calibrate Ligand-ligand Interaction on Nanocrystals via the Dynamic Volume of Chain Segments The intermolecular ligand-ligand interaction is crucial for the surface chemistry, solution properties, and self-assembly processes of colloidal nanocrystals (NCs). The studies on the ligand-ligand interaction are hampered by the disordered and dynamic nature of the surface, the low electron contrast of organic moieties, and the non-characteristic weak intermolecular forces. Solid-state nuclear magnetic resonance (NMR) can provide site-specific information on organic ligands and especially the motional behavior of chain segments. In this work, we develop an advanced solid-state NMR measurement and modelling strategy to quantify the “dynamic volume” of chain segments. The dynamic volume depicts the accessible space of a chain segment under the confinement of neighboring molecules, and is inversely proportional to the intermolecular interaction energy. The ligand-ligand interaction energies have been obtained for NCs with alkanoate ligands of different lengths. We show that the calculated ligand-ligand interaction energy determines solution dispersity and the melting transitions of NCs. This dynamic volume concept can be extended beyond experimental NMR measurements and offer semi-empirical predictions of the interaction energies for arbitrary selections of alkanoate ligands. Our study not only advances the quantitative understanding of ligand-ligand interaction on NCs but also establishes novel tactics to calibrate weak intermolecular interactions. Ligand (biochemistry) ; Intermolecular force ; Chemical physics ; Chemistry ; Interaction energy ; Dispersity ; Molecule ; Resonance (particle physics) ; Crystallography ; Computational chemistry ; Physics ; Atomic physics ; Organic chemistry Advanced NMR Techniques and Applications ; NMR spectroscopy and applications ; Advanced Neuroimaging Techniques and Applications
Authors: Xiaonuan Wang | Yajie Qian | Hong Chen | Xiang Li | Ai Zhang | Changyu Chen | Yueling He | Gang Xue
Source: Research Square (preprint, 2022-09-02)
Field: Chemistry — Organic Chemistry

Hydrothermal converting quinonimine dye into pyrrolic-N for sustainable activated carbon regeneration Adsorption ; Methylene blue ; Hydrothermal circulation ; Carbon fibers ; Activated carbon ; Desorption ; Thermal desorption ; Chemistry ; Regeneration (biology) ; Dyeing ; Chemical engineering ; Materials science ; Nuclear chemistry ; Organic chemistry ; Catalysis ; Photocatalysis ; Composite number ; Composite material Nanomaterials for catalytic reactions ; Adsorption and biosorption for pollutant removal ; Advanced Photocatalysis Techniques
Authors: Shengqian Ruan | Shikun Chen | Yajun Zhang | Dongming Yan | Yi Liu | Xiaofeng Liu | Hideo Hosono
Source: Research Square (preprint, 2022-08-16)
Field: Materials Science — Materials Chemistry

Molecular level hybridized hydrophobic ceramics for corrosion protection Corrosion ; Ceramic ; Materials science ; Business ; Nanotechnology ; Metallurgy Magnesium Oxide Properties and Applications ; Concrete and Cement Materials Research ; Chemical Synthesis and Characterization
Authors: Matteo Orfano | Jacopo Perego | Francesca Cova | Charl X. Bezuidenhout | Sergio Piva | Christophe Dujardin | Benoît Sabot | Sylvier Pierre | Pavlo Mai | Christophe Daniel | Silvia Bracco | A. Vedda | Angiolina Comotti | Angelo Monguzzi
Source: ChemRxiv (preprint, 2022-12-06)
Field: Chemistry — Inorganic Chemistry

Efficient radioactive gas detectionby porous metal-organic framework scintillating nanocrystals. Natural radioactive gases and anthropogenic radionuclides such as radon, xenon, hydrogen and krypton isotopes, need to be carefully monitored to be properly managed as pathogenic agents, radioactive diagnostic agents or indicators of nuclear activity. State-of-the-art gas detectors based on liquid scintillators suffer from many drawbacks such as lengthy sample preparation procedures and limited solubility of gaseous radionuclides, which produces a detrimental effect on measurement sensitivity. A potential breakthrough solution to this problem is using solid porous scintillators that act as gas concentrators and, therefore, could increase detection sensitivity. Highly porous scintillating metal-organic frameworks (MOFs) stand out as relevant materials for the realization of these devices. We demonstrate the capability of porous hafnium-based MOF nanocrystals exploiting dicarboxy-9,10-diphenylanthracene (DPA) as a scintillating conjugated ligand to detect gas radionuclides. The nanocrystals show fast scintillation properties in the nanosecond domain, a fluorescence quantum yield of ~40% and an accessible porosity suitable to host noble gas atoms and ions. The adsorption and detection of radionuclides such as 85Kr, 222Rn and 3H have been explored for these MOFs utilising a newly developed device based on a time coincidence technique. MOF nanocrystals demonstrate an improved sensitivity for these radionuclides compared to a reference detector, showing an excellent linear response down to an activity value lower than 1 kBq·m-3 that outperforms commercial devices. These results strongly support the possible use of scintillating porous MOF nanocrystals as the building block of ultrasensitive sensors for detecting natural and anthropogenic radioactive gases. Krypton ; Scintillation ; Porosity ; Nanocrystal ; Materials science ; Radionuclide ; Radioluminescence ; Xenon ; Scintillator ; Radiochemistry ; Nanotechnology ; Detector ; Chemistry ; Nuclear physics ; Physics ; Optics Metal-Organic Frameworks: Synthesis and Applications ; Radiation Detection and Scintillator Technologies ; Catalysis and Oxidation Reactions
Authors: Hao Song | Jiangmin Guo | Shaojun Liu | Yu Zhang | Weihong Wu | Chenghang Zheng | Xiang Gao
Source: Frontiers in Energy Research (article, 2022-03-28)
Field: Materials Science — Materials Chemistry

Effect of Dimethyl Formamide (DMF) on Vanadium Reloading Over V-Ti SCR Catalyst Active components reloading is critical process for the catalyst regeneration, which is limited by the low adsorption capacity and unwilling distribution of desired components to the catalyst surface. Herein we demonstrated that with dimethyl formamide(DMF) modification and sequentially reloading of vanadium, the traditional V-Ti SCR catalyst, which uses vanadium as the active components and titanium as the carrier, showed the significantly improved DeNOx performance, owing to the increased adsorption capacity and desired distribution of vanadium. When the DMF concentration was 6%, the adsorption capacity of the promoted catalyst was 3.58 and 6.57 mg/g under vanadyl ion concentrations of 1.5 and 3 g/L, respectively, 135 and 147% higher than that of the original catalyst. Adsorption kinetics demonstrated that the pseudo-second-order kinetic model better describes the process by which vanadyl ions adsorb onto the catalyst. In addition, the adsorption equilibrium indicated that Langmuir model was a closer fit for the vanadyl ion adsorption to the promoted catalyst. After DMF modification, the vanadyl ions were first adsorbed onto the functional groups on the catalyst surface, substantially increasing the vanadium loading on the catalyst surface while limiting the increase in vanadium content within the interior of catalyst, which was conducive to enhancing the DeNOx activity and reducing the increase in the SO 2 /SO 3 conversion. When the vanadium adsorption capacity was 3.5 mg/g, the increase in the DeNOx activity of the promoted catalyst was 68.1% higher than that of the original catalyst, whereas the increase in SO 2 /SO 3 conversion was 28.9% lower than that of the original catalyst. Thus, in the regeneration of SCR catalysts vanadium initial concentration and loading could be reduced. Vanadium ; Catalysis ; Adsorption ; Formamide ; Inorganic chemistry ; Chemistry ; Organic chemistry Catalytic Processes in Materials Science ; Metal Extraction and Bioleaching ; Catalysis and Oxidation Reactions
Authors: Honghong Wang | Zhixin Xiong | Yunchao Hu | Zhijian Liu | Ying Wang | Haoran Huang | Long Liang
Source: Research Square (preprint, 2022-10-20)
Field: Chemistry — Analytical Chemistry

Application of SWSRA-DS Algorithm in Improving the Model Transfer for Near Infrared Analysis of Pulpwood Holocellulose Abstract The SWSRA-DS combined algorithm was proposed with the goal of sharing the NIR analysis model of the holocellulose content of pulpwood on three different types of spectroscopic instruments. That was, the Screening wavelengths based on spectrum ratio analysis (SWSRA) algorithm was used to select the wavelengths with good stability and consistency. These important wavelength variables, which were insensitive to the measured sample parameters, can reduce the differences in sample information response by different instruments or measurement conditions. Then the systematic errors that still existed after the SWSRA method calibration were further calibrated using the Direct Standardization (DS) method on the basis of these wavelengths. This combined algorithm can improve the generalizability of the master model, reduce the spectrum matrix dimension, and make the model transfer more stabilized and simply. The results show that the SWSRA-DS combined algorithm was able to reduce the RMSEP of the master model to predict the holocellulose content of samples measured on the target 1 and target 2 instruments from 2.0114 and 9.4518 to 0.9641 and 1.0798, respectively. This result was compared with the calibration results of SWSRA and DS alone and the commonly used PDS and S/B model transfer algorithms to transfer performance was significantly improved, which provides a new idea for the sharing of NIR analysis models among different types of spectroscopic instruments. Calibration ; Algorithm ; Wavelength ; Computer science ; Consistency (knowledge bases) ; Repeatability ; Near-infrared spectroscopy ; Mathematics ; Optics ; Artificial intelligence ; Physics ; Statistics Spectroscopy and Chemometric Analyses ; Remote Sensing in Agriculture ; Wood and Agarwood Research
Authors: Shubham Sukumar Awate | Brendan Mostek | Shalini Kumari | Chengye Dong | Joshua A. Robinson | Ke Xu | Susan K. Fullerton‐Shirey
Source: ChemRxiv (preprint, 2022-11-18)
Field: Materials Science — Materials Chemistry

Impact of Large Gate Voltages and Ultra-thin Polymer Electrolytes on Carrier Density in Electric-double-layer-gated Two-dimensional Crystal Transistors Electric double layer (EDL) gating can induce large capacitance densities (∼1−10 μF/cm^2) in two-dimensional (2D) semiconductors; however, several properties of the electrolyte limit performance. One property is the electrochemical activity which limits the gate voltage (VG) that can be applied and therefore the maximum extent to which carriers can be modulated. A second property is electrolyte thickness, which sets the response speed of the EDL gate, and therefore the timescale over which the channel can be doped. Typical thicknesses are on the order of microns, but thinner electrolytes (nanometers) are needed for very-large-scale-integration (VLSI) both in terms of physical thickness and the speed that accompanies scaling. In this study, finite element modeling of an EDL-gated field-effect transistor (FET) is used to self-consistently couple ion transport in the electrolyte to carrier transport in the semiconductor, in which density of states, and therefore, quantum capacitance is included. The model reveals that 50 to 65% of the applied potential drops across the semiconductor, leaving 35 to 50% to drop across the two EDLs. Accounting for the potential drop in the channel suggests that higher carrier densities can be achieved at larger applied VG without concern for inducing electrochemical reactions. This insight is tested experimentally via Hall measurements of graphene FETs for which VG is extended from ±3 to ±6 V. Doubling the gate voltage increases the sheet carrier density by an additional 2.3×10^13 cm^−2 for electrons and 1.4×10^13 cm^−2 for holes without inducing electrochemistry. To address the need for thickness scaling, the thickness of the solid polymer electrolyte, polyethylene oxide (PEO):CsClO_4, is decreased from 1 μm to 10 nm and used to EDL- gate graphene FETs. Sheet carrier density measurements on graphene Hall bars prove that the carrier densities remain constant throughout the measured thickness range (10 nm−1 μm). The results indicate promise for overcoming the physical and electrical limitations to VLSI while taking advantage of the ultrahigh carrier densities induced by EDL gating. Materials science ; Transistor ; Electrolyte ; Quantum capacitance ; Semiconductor ; Optoelectronics ; Voltage drop ; Capacitance ; Electric field ; Voltage ; Electron mobility ; Nanotechnology ; Electrical engineering ; Chemistry ; Physics ; Electrode Graphene research and applications ; Nanowire Synthesis and Applications ; Semiconductor materials and devices