jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Kai Yang | Cheng Zhou | Zhenhuan Yang | Yu Lan | Ming Cai | Changqing Wu | Peilong Sun
Source: Food Science & Nutrition (article, 2019-05-15)
Field: Chemistry — Spectroscopy

Establishing a method of HPLC involving precolumn derivatization by 2,2′‐dithiobis (5‐nitropyridine) to determine the sulfites in shrimps in comparison with ion chromatography Although sulfites are widely used in shrimp processing, the contents of residual sulfite need to be strictly controlled due to their potential toxicity. In this paper, a novel method was developed for determination of the free and total sulfites in shrimps. Major procedures of the method includes separation of free and total sulfites with ultrasound-assisted extraction and pH adjustment for 20 min, then a precolumn derivatization was conducted by 2,2'-Dithiobis (5-nitropyridine) and verified by LC-MS, and finally HPLC coupled with an ultraviolet (UV) detector was carried out. Results indicated that the UV absorption wavelength shifted from 213 (sulfites) to 320 nm (new disulfide compounds), significantly reducing the interference of natural occurring compounds and solvents in the matrix. The standard curves exhibited a good linear range of 3.2-51.2 mg/L (<i>R</i> <sup>2</sup> = 0.9996). The limit of detection (LOD) and limit of quantification (LOQ) were 0.3 and 1.0 mg/L, respectively. The contents of free and total sulfite in frozen shrimps were 26.58 ± 0.48 and 31.44 ± 0.83 mg/kg calculated by SO<sub>2</sub>, respectively. These were similar (<i>p</i> > 0.05) to the data obtained by the method of ion chromatography. In conclusion, the new developed method has been proved to be a reliable and economic method for effective determination of free and total sulfites in the shrimps, and the method could be expanded in determination of the sulfites in other food products. Sulfite ; Chemistry ; Chromatography ; Detection limit ; Derivatization ; High-performance liquid chromatography ; Shrimp ; Ion chromatography ; Extraction (chemistry) ; Organic chemistry ; Fishery Analytical Chemistry and Chromatography ; Analytical chemistry methods development ; Advanced Chemical Sensor Technologies
Authors: Mao‐Mao Zhang | Guangjie Zhao | Juan Guo | Бо Лю | Xiaomei Jiang | Yafang Yin
Source: Molecules (article, 2019-02-22)
Field: Chemistry — Organic Chemistry

A GC-MS Protocol for Separating Endangered and Non-endangered Pterocarpus Wood Species <i>Pterocarpus santalinus</i> and <i>Pterocarpus tincorius</i> are commonly used traded timber species of the genus <i>Pterocarpus</i>. <i>P. santalinus</i> has been listed in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). As a non-CITES species, <i>P. tincorius</i> is also indiscriminately labeled as <i>P. santalinus</i> due to the similar macroscopic and microscopic features with <i>P. santalinus.</i> In order to understand the molecular discrimination between these easily confused species, xylarium heartwoods of these two species were extracted by three different kinds of solvents and analyzed using gas chromatography⁻mass spectrometry (GC-MS). Multivariate analyses were also applied for the selection of marker compounds that are distinctive between <i>P. santalinus</i> and <i>P. tincorius</i>. A total of twenty volatile compounds were detected and tentatively identified in three kinds of extracts, and these compounds included alcohols, stilbenoids, esters, aromatic hydrocarbons, ketones, miscellaneous, phenols, and flavonoids. GC-MS analyses also revealed that extraction solvents including ethanol and water (EW), ethyl acetate (EA), and benzene⁻ethanol (BE) gave the best chemotaxonomical discrimination in the chemical components and relative contents of the two <i>Pterocarpus</i> species. After chemometric analyses, EW displayed higher predictive accuracy (100%) than those of EA extract (83.33%) and BE extract (83.33%). Furthermore, spathulenol (17.58 min) and pterostilbene (23.65 min) were elucidated as the critical compounds for the separation of the EW extracts of <i>P. santalinus</i> and <i>P. tinctorius</i>. Thus, a protocol of GC-MS and multivariate analyses was developed to use for successfully distinguishing <i>P. santalinus</i> from <i>P. tinctorius</i>. Endangered species ; Ethyl acetate ; Biology ; Chromatography ; Botany ; Chemistry ; Ecology ; Habitat Wood and Agarwood Research ; Cultural Heritage Materials Analysis ; Biological Stains and Phytochemicals
Authors: Abdelmotaleb Elokil | Tharwat A. Imbabi | Hany I. Mohamed | Khaled Abouelezz | Omar A. Ahmed‐Farid | Shishay Girmay | Islam Ibrahim Sabike | Huazhen Liu
Source: Animals (article, 2019-12-12)
Field: Chemistry — Organic Chemistry

Zinc and Copper with New Triazine Hydrazone Ligand: Two Novel Organic Complexes Enhanced Expression of Peptide Growth Factors and Cytokine Genes in Weaned V-Line Rabbit Two novel transitional organic Zn/Cu complexes based on a new biocompatible bidentate triazine-hydrazone ligand (Thz) was designed, synthesized, and evaluated in this study. This study evaluated the effects of injecting 60 mg of Zn and 40 mg of Cu in three different forms, twice per week, for eight weeks on growth performance, expression of growth factors and cytokine genes, carcass yield, blood biochemicals, and intestinal morphology in weaned rabbits. The tested complexes were sulfate (Cu/ZnSO<sub>4</sub>), montmorillonite (Cu/Zn-Mnt), and triazine hydrazone (Cu/Zn-Thz). A total of 60 V-line weaned rabbits at four weeks of age were assigned to four treatments (<i>n</i> = 15), which were intramuscularly injected with 0.5 mL of either (1) saline (control) or saline containing (2) Cu/ZnSO<sub>4</sub>, (3) Cu/Zn-Mnt, or (4) Cu/Zn-Thz. Compared to the controls, the rabbits injected with Cu/Zn-Thz showed a higher (<i>p</i> < 0.01) growth rate, carcass yield (<i>p</i> < 0.05), and liver expression of insulin like growth factor-1 (<i>IGF-1</i>), growth hormone receptor (<i>GHR</i>), fibroblast growth factor-1 (<i>FGF1</i>), and transforming growth factor beta-1 (<i>TGFB1</i>) (<i>p</i> < 0.05), as well as better jejunum morphometric variables (<i>p</i> < 0.05). On the other hand, mRNA of <i>FGF1</i>, <i>TGF1, TCIRG1</i>, and adenosine deaminase (<i>ADA</i>) were higher expressed (<i>p</i> < 0.05) in the spleen tissues of Cu/Zn-Mnt group. Collectively, the results indicated that our novel synthesized organic complexes of Zn/Cu-Thz proved to be a suitable feed supplement, as it increased rabbit productive performance through enhancing expression of peptide growth factors and cytokine genes. Triazine ; Chemistry ; Zinc ; Hydrazone ; Copper ; Peptide ; Cytokine ; Gene ; Ligand (biochemistry) ; Molecular biology ; Biology ; Stereochemistry ; Biochemistry ; Receptor ; Polymer chemistry ; Genetics ; Organic chemistry Synthesis and Characterization of Heterocyclic Compounds ; RNA Interference and Gene Delivery ; DNA and Nucleic Acid Chemistry
Authors: Zhihua Wang | Yunfei Xu | Yi Zhao | Zhimin Li | Yang Liu | Jiajun Hong
Source: Energies (article, 2019-11-13)
Field: Chemistry — Analytical Chemistry

Role of Shearing Dispersion and Stripping in Wax Deposition in Crude Oil Pipelines Wax deposition during crude oil transmission can cause a series of negative effects and lead to problems associated with pipeline safety. A considerable number of previous works have investigated the wax deposition mechanism, inhibition technology, and remediation methods. However, studies on the shearing mechanism of wax deposition have focused largely on the characterization of this phenomena. The role of the shearing mechanism on wax deposition has not been completely clarified. This mechanism can be divided into the shearing dispersion effect caused by radial migration of wax particles and the shearing stripping effect caused by hydrodynamic scouring. From the perspective of energy analysis, a novel wax deposition model was proposed that considered the flow parameters of waxy crude oil in pipelines instead of its rheological parameters. Considering the two effects of shearing dispersion and shearing stripping coexist, with either one of them being the dominant mechanism, a shearing dispersion flux model and a shearing stripping model were established. Furthermore, a quantitative method to distinguish between the roles of shearing dispersion and shearing stripping in wax deposition was developed. The results indicated that the shearing mechanism can contribute an average of approximately 10% and a maximum of nearly 30% to the wax deposition process. With an increase in the oil flow rate, the effect of the shearing mechanism on wax deposition is enhanced, and its contribution was demonstrated to be negative; shear stripping was observed to be the dominant mechanism. A critical flow rate was observed when the dominant effect changes. When the oil flow rate is lower than the critical flow rate, the shearing dispersion effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. When the oil flow rate is higher than the critical flow rate, the shearing stripping effect is the dominant effect; its contribution rate increases with an increase in the oil flow temperature. This understanding can be used to design operational parameters of the actual crude oil pipelines and address the potential flow assurance problems. The results of this study are of great significance for understanding the wax deposition theory of crude oil and accelerating the development of petroleum industry pipelines. Wax ; Shearing (physics) ; Materials science ; Deposition (geology) ; Volumetric flow rate ; Petroleum engineering ; Composite material ; Geology ; Mechanics ; Physics Petroleum Processing and Analysis ; Enhanced Oil Recovery Techniques ; Hydrocarbon exploration and reservoir analysis
Authors: Cameron Mura | Stella Veretnik | Philip E. Bourne
Source: Protein Science (article, 2019-10-09)
Field: Materials Science — Materials Chemistry

The <i>Urfold</i> : Structural similarity just above the superfold level? We suspect that there is a level of granularity of protein structure intermediate between the classical levels of "architecture" and "topology," as reflected in such phenomena as extensive three-dimensional structural similarity above the level of (super)folds. Here, we examine this notion of architectural identity despite topological variability, starting with a concept that we call the "Urfold." We believe that this model could offer a new conceptual approach for protein structural analysis and classification: indeed, the Urfold concept may help reconcile various phenomena that have been frequently recognized or debated for years, such as the precise meaning of "significant" structural overlap and the degree of continuity of fold space. More broadly, the role of structural similarity in sequence↔structure↔function evolution has been studied via many models over the years; by addressing a conceptual gap that we believe exists between the architecture and topology levels of structural classification schemes, the Urfold eventually may help synthesize these models into a generalized, consistent framework. Here, we begin by qualitatively introducing the concept. Granularity ; Similarity (geometry) ; Topology (electrical circuits) ; Structural similarity ; Sequence (biology) ; Computer science ; Function (biology) ; Meaning (existential) ; Space (punctuation) ; Theoretical computer science ; Mathematics ; Artificial intelligence ; Epistemology ; Evolutionary biology ; Combinatorics ; Biology Enzyme Structure and Function ; Genomics and Phylogenetic Studies ; Protein Structure and Dynamics
Authors: Bao-Lin Xiao | Yan-Na Ning | Nan‐Nan Niu | Di Li | Ali Akbar Moosavi‐Movahedi | Nader Sheibani | Jun Hong
Source: Scientific Reports (article, 2019-03-13)
Field: Chemistry — Inorganic Chemistry

Steered molecular dynamic simulations of conformational lock of Cu, Zn-superoxide dismutase The conformational lock was a bio-thermodynamic theory to explain the characteristics of interfaces in oligomeric enzymes and their effects on catalytic activity. The previous studies on superoxide dismutases (Cu, Zn-SODs) showed that the dimeric structure contributed to the high catalytic efficiency and the stability. In this study, steered molecular dynamics simulations were used firstly to study the main interactions between two subunits of Cu, Zn-SODs. The decomposition process study showed that there were not only four pairs of hydrogen bonds but also twenty-five residue pairs participating hydrophobic interactions between A and B chains of SOD, and van der Waals interactions occupied a dominant position among these residue pairs. Moreover, the residue pairs of hydrogen bonds played a major role in maintaining the protein conformation. The analysis of the energy and conformational changes in the SMD simulation showed that there were two groups (two conformational locks) between A and B chains of SOD. The first group consisted of one hydrogen-bond residues pair and seven hydrophobic interactions residues pairs with a total average energy of -30.10 KJ/mol, and the second group of three hydrogen-bond residues pair and eighteen hydrophobic interactions residues pairs formed with a total average energy of -115.23 KJ/mol. Hydrogen bond ; Residue (chemistry) ; van der Waals force ; Chemistry ; Molecular dynamics ; Crystallography ; Hydrophobic effect ; Catalysis ; Computational chemistry ; Molecule ; Biochemistry ; Organic chemistry Metal-Catalyzed Oxygenation Mechanisms ; Metal complexes synthesis and properties ; Protein Structure and Dynamics
Authors: Jiaming Zou | Kaifa Liao | Li Xiang | Mouwu Liu | Fan Xie | Xinlin Liu | Jianglai Yu | Xiaonan An | Yanfei Wang
Source: Journal of Inorganic and Organometallic Polymers and Materials (article, 2019-06-29)
Field: Materials Science — Polymers and Plastics

Synthesis of Poly(cyclotriphosphazene-co-4,4′-diaminodiphenysulfone) Microspheres and Their Adsorption Properties for Cationic Dyes (Methylene Blue) Cationic polymerization ; Adsorption ; Methylene blue ; Materials science ; Chemical engineering ; Polymer chemistry ; Polymerization ; Precipitation polymerization ; Polymer ; Chemistry ; Nuclear chemistry ; Organic chemistry ; Catalysis ; Radical polymerization ; Photocatalysis ; Composite material Flame retardant materials and properties ; Conducting polymers and applications ; Synthesis of Tetrazole Derivatives
Authors: Wei Huang | Shuai Pan | Qingmei Yu | Xiao Liu | Yanghua Liu | Ruijiang Liu
Source: Journal of Inorganic and Organometallic Polymers and Materials (article, 2019-03-19)
Field: Chemistry — Organic Chemistry

Adsorption Performance of Methyl Blue onto Magnetic Ni(1−x−y)CuyZnxFe2O4 Nanoparticles Prepared by A Novel Alcohol-Assisted Combustion Method Adsorption ; Calcination ; Materials science ; Langmuir adsorption model ; Nanoparticle ; Methyl blue ; Chemical engineering ; Diffusion ; Magnetic nanoparticles ; Kinetics ; Nuclear chemistry ; Chemistry ; Organic chemistry ; Nanotechnology ; Catalysis ; Thermodynamics ; Photocatalysis Nanomaterials for catalytic reactions ; Adsorption and biosorption for pollutant removal ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Shreenath Krishnamurthy | Richard Blom | Maria‐Chiara Ferrari | Stefano Brandani
Source: Adsorption (article, 2019-08-29)
Field: Chemistry — Inorganic Chemistry

Adsorption and diffusion of CO2 in CPO-27–Ni beads The present work involves the scale-up and characterization of CPO-27–Ni metal organic framework using a range of experimental techniques aimed at determining equilibrium and kinetic parameters to assess its potential for post-combustion carbon capture. CPO-27–Ni was prepared from its precursors by molecular gastronomy methods in kilogram scale. Adsorption of isotherms of pure CO2 and N2 were obtained for different temperatures on these beads, using a volumetric apparatus and the isotherms were fitted to a dual-site Langmuir model. A series of experiments were then carried out in the volumetric apparatus by dosing a known volume of CO2 and the pressure was monitored with time. The diffusional time constants were then extracted by fitting the series of curves to an isothermal diffusion model. From the time constants, the values of the diffusivities were obtained and compared with the values obtained from first principles correlations, which employed the pore size, and the porosity values from independent mercury porosimetry experiments. The results from the analysis showed that the transport of CO2 in the beads was well described by a combination of Knudsen and viscous diffusion mechanisms. Experiments were also carried out using a zero-length column (ZLC) apparatus by preparing a 10% CO2–He and 10% CO2–N2 mixture. The analysis of the ZLC curves showed that the two different carrier gases had an effect of the long-time slope, indicating the presence of a macropore-controlled diffusion mechanism. Porosimetry ; Adsorption ; Diffusion ; Isothermal process ; Chemistry ; Thermodynamics ; Analytical Chemistry (journal) ; Langmuir ; Knudsen diffusion ; Porosity ; Materials science ; Chromatography ; Porous medium ; Physical chemistry ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Covalent Organic Framework Applications ; Carbon Dioxide Capture Technologies
Authors: Carlos E. Hernandez‐Tamargo | Alexander J. O’Malley | Ian P. Silverwood | Nora H. de Leeuw
Source: Catalysis Science & Technology (article, 2019-01-01)
Field: Chemistry — Inorganic Chemistry

Molecular behaviour of phenol in zeolite Beta catalysts as a function of acid site presence: a quasielastic neutron scattering and molecular dynamics simulation study The dynamic behaviour of phenol in zeolite Beta is strongly influenced by the presence of Brønsted acid sites. Zeolite ; Catalysis ; Quasielastic neutron scattering ; Phenol ; Molecular dynamics ; Neutron scattering ; BETA (programming language) ; Chemistry ; Brønsted–Lowry acid–base theory ; Function (biology) ; Physical chemistry ; Neutron ; Inelastic neutron scattering ; Organic chemistry ; Computational chemistry ; Physics ; Nuclear physics ; Biology Zeolite Catalysis and Synthesis ; Catalysis and Oxidation Reactions ; Spectroscopy and Quantum Chemical Studies
Authors: Sajjad Khezrianjoo | Jechan Lee | Ki‐Hyun Kim | Vanish Kumar
Source: Catalysts (article, 2019-10-21)
Field: Materials Science — Materials Chemistry

Eco-Toxicological and Kinetic Evaluation of TiO2 and ZnO Nanophotocatalysts in Degradation of Organic Dye In this study, the photocatalytic degradation of azo dye “Food Black 1” (FB1) was investigated using TiO2 and ZnO nanoparticles under ultraviolet (UV) light. The performances of the two photocatalysts were evaluated in terms of key parameters (e.g., decolorization, dearomatization, mineralization, and detoxification of dye) in relation to variables including pre-adsorption period, pH, and temperature. Under acidic conditions (pH 5), the ZnO catalyst underwent photocorrosion to increase the concentration of zinc ions in the system, thereby increasing the toxic properties of the treated effluent. In contrast, TiO2 efficiently catalyzed the degradation of the dye at pH 5 following the Langmuir–Hinshelwood (L–H) kinetic model. The overall results of this study indicate that the decolorization rate of TiO2 on the target dye was far superior to ZnO (i.e., by 1.5 times) at optimum catalyst loading under UV light. Degradation (telecommunications) ; Chemistry ; Catalysis ; Adsorption ; Mineralization (soil science) ; Zinc ; Effluent ; Photochemistry ; Photocatalysis ; Nuclear chemistry ; Chemical engineering ; Inorganic chemistry ; Organic chemistry ; Environmental engineering Nanoparticles: synthesis and applications ; TiO2 Photocatalysis and Solar Cells ; Nanomaterials for catalytic reactions
Authors: Masashi Kishimoto | Hironori Onaka | Hiroshi Iwai | Motohiro Saito | Hideo Yoshida
Source: Journal of Power Sources (article, 2019-05-21)
Field: Materials Science — Materials Chemistry

Physicochemical impedance modeling of solid oxide fuel cell anode as an alternative tool for equivalent circuit fitting Anode ; Electrical impedance ; Capacitance ; Equivalent circuit ; Solid oxide fuel cell ; Materials science ; Dielectric spectroscopy ; Oxide ; Current density ; Analytical Chemistry (journal) ; Ion ; Electrochemistry ; Chemistry ; Electrode ; Voltage ; Electrical engineering ; Physics ; Metallurgy ; Engineering ; Physical chemistry ; Chromatography Advancements in Solid Oxide Fuel Cells ; Electronic and Structural Properties of Oxides ; Fuel Cells and Related Materials
Authors: Xiao Xing | Jiayu Zhou | Shouxin Zhang | Hao Zhang | Zili Li | Zhenjun Li
Source: Materials (article, 2019-02-15)
Field: Materials Science — Metals and Alloys

Quantification of Temperature Dependence of Hydrogen Embrittlement in Pipeline Steel The effects of temperature on bulk hydrogen concentration and diffusion have been tested with the Devanathan⁻-Stachurski method. Thus, a model based on hydrogen potential, diffusivity, loading frequency, and hydrostatic stress distribution around crack tips was applied in order to quantify the temperature's effect. The theoretical model was verified experimentally and confirmed a temperature threshold of 320 K to maximize the crack growth. The model suggests a nanoscale embrittlement mechanism, which is generated by hydrogen atom delivery to the crack tip under fatigue loading, and rationalized the Δ<i>K</i> dependence of traditional models. Hence, this work could be applied to optimize operations that will prolong the life of the pipeline. Hydrogen embrittlement ; Embrittlement ; Materials science ; Pipeline (software) ; Hydrogen ; Metallurgy ; Corrosion ; Engineering ; Chemistry ; Mechanical engineering Hydrogen embrittlement and corrosion behaviors in metals ; Material Properties and Failure Mechanisms ; Corrosion Behavior and Inhibition
Authors: Dong Liu | Kai Guo | Fawei Tang | Fei Mao | Xuemei Liu | Chao Hou | Haibin Wang | Hao Lü | Xiaoyan Song
Source: Chemistry of Materials (article, 2019-11-27)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Selecting Doping Elements by Data Mining for Advanced Magnets Compared with other material performances, magnetic properties are more closely related to the electronic structure and sensitive to the material composition. To date, no unified approach has been reported to understand the complicated influence of composition on a material’s magnetic properties. As one of the two most representative permanent magnetic systems, Sm-Co-based materials have been developed in terms of composition design mainly by empirical exploration. Taking advantage of a unique home-built Materials Genome Initiative database of Sm-Co systems, this work reports a data-driven material development that aims at high saturation magnetization, along with excellent comprehensive magnetic performance. A novel method using a unified “indicator” capable of precisely evaluating effects of doping elements on saturation magnetization was developed, and the priority of possible elements was predicted by extending the screening of elements to the periodic table, from which some elements that have never been tried in magnetic materials are discovered. By this approach, a top level of saturation magnetization was achieved in a series of prepared stoichiometric Sm-Co-based alloys, which also have high coercivity and high remanence in the same system. The strategy proposed here will be applicable on doping element selections for a large variety of material property modulations. Remanence ; Coercivity ; Magnet ; Materials science ; Magnetization ; Doping ; Saturation (graph theory) ; Characterization (materials science) ; Computer science ; Condensed matter physics ; Nanotechnology ; Magnetic field ; Mechanical engineering ; Optoelectronics ; Physics ; Engineering ; Mathematics Magnetic Properties of Alloys ; Magnetic Properties and Applications ; Magnetic properties of thin films