jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: T. Prabhakaran | Ramalinga Viswanathan Mangalaraja | Marcus Vinícius‐Araújo | Andris F. Bakuzis | Fanny Béron | Arun Thirumurugan | Juliano C. Denardin | J.A. Jiménez | Ali Akbari‐Fakhrabadi
Source: Journal of the American Ceramic Society (article, 2020-04-20)
Field: Materials Science — Materials Chemistry

Single‐phase and binary phase nanogranular ferrites for magnetic hyperthermia application Abstract The study demonstrates the performance of heating efficiency in single‐phase and binary phase spinel ferrite nanosystems. Ferrimagnetic cobalt ferrite (CoFe 2 O 4 ) (CFO) and superparamagnetic copper ferrite/copper oxide (CuFe 2 O 4 /CuO) (CuF) nanosystems of different particle sizes were synthesized through a microwave‐assisted coprecipitation method. The heating behavior was observed in range of both field amplitudes (8‐24 kA/m at 516 kHz) and frequencies (325‐973 kHz at 12 kA/m). The heating efficiency was analyzed and compared by means of particle size, magnetization, effective anisotropy constant, and Néel relaxation mechanism. Indeed, the heating rate was maximized in larger ferrite particles with low effective anisotropy constant. Moreover, though the magnetization and effective anisotropy constant of single‐phase CoFe 2 O 4 nanoparticles were higher, the binary phase CuFe 2 O 4 /CuO nanosystems of similar crystallite size (28 nm) exhibited superior heating efficiency (4.21°C/s). For a field amplitude and frequency of 24 kA/m and 516 kHz, the heating rate of CuF and CFO ferrites with different crystallite sizes decreased in the order of 4.21 &gt; 2.14 &gt; 0.58 &gt; 0.52 °C/s for 29 nm &gt; 25 nm &gt; 12 nm &gt; 15 nm , respectively. The results emphasize that binary phase ferrite nanoparticles are better thermoseeds than the single‐phase ferrites for the magnetic hyperthermia application. Materials science ; Ferrimagnetism ; Superparamagnetism ; Ferrite (magnet) ; Crystallite ; Coprecipitation ; Phase (matter) ; Spinel ; Anisotropy ; Analytical Chemistry (journal) ; Remanence ; Nuclear magnetic resonance ; Magnetization ; Condensed matter physics ; Composite material ; Magnetic field ; Metallurgy ; Chemistry ; Optics ; Inorganic chemistry Magnetic Properties and Synthesis of Ferrites ; ZnO doping and properties ; Multiferroics and related materials
Authors: Andrea Pinto | Giulia Spigolon | Raquel Gavara | Cristiano Zonta | Giulia Licini | Laura Rodrı́guez
Source: Dalton Transactions (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Tripodal gold(<scp>i</scp>) polypyridyl complexes and their Cu<sup>+</sup>and Zn<sup>2+</sup>heterometallic derivatives. Effects on luminescence Three gold(i) tripodal complexes containing the tris(2-pyridylmethyl)amine (TPA) ligand coordinated to Au-PR<sub>3</sub> moieties (PR<sub>3</sub> = 1,3,5-triaza-7-phosphatricyclo[3.3.1.13.7]decane, PTA (1), 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane, DAPTA (2) and triphenylphosphane (3)) were prepared together with a cage-like structure containing triphosphane 1,1,1-tris(diphenylphosphinomethyl)ethane (4). The luminescence of these complexes has been studied and they show a red shift upon the formation of heterometallic complexes by reaction with Zn(NO<sub>3</sub>)<sub>2</sub>, CuCl and [Cu(CH<sub>3</sub>CN)<sub>4</sub>]BF<sub>4</sub>. The different coordination motifs of the Zn<sup>2+</sup> and Cu<sup>+</sup> heterometallic species and the resulting changes in the recorded absorption, emission and NMR spectra were analysed and supported by TD-DFT calculations. Luminescence ; Chemistry ; Nonane ; Tris ; Ligand (biochemistry) ; Amine gas treating ; Tripodal ligand ; Crystallography ; Decane ; Absorption spectroscopy ; Stereochemistry ; Medicinal chemistry ; Crystal structure ; Materials science ; Organic chemistry Organometallic Complex Synthesis and Catalysis ; Metal complexes synthesis and properties ; Nanocluster Synthesis and Applications
Authors: Jack Ward Thomas | Adam Polak | Gerald M. Bonner | David Logie | Malcolm H. Dunn | Jonathan C. F. Matthews | David J. M. Stothard
Source: Optics Express (article, 2020-01-18)
Field: Chemistry — Spectroscopy

Widely-tunable mid-infrared ring cavity pump-enhanced OPO and application in photo-thermal interferometric trace ethane detection The development of a broadly and accurately tunable single-frequency mid-infrared laser source and its application to a sensitive laser absorption detection method are described. Photo-thermal interferometric spectroscopy is employed as a phase-sensitive method to detect the minute refractive index change caused by the heating of a gas under laser radiation. A separate probe beam allows for the spectrally-interesting mid-infrared region to be examined whilst utilizing low cost, high detectivity photodetectors in the visible/near-infrared region. We also describe the implementation of a Sagnac interferometer to minimize the effects of environmental perturbation and provide inherent passive stability. A continuous-wave ring-cavity pump-enhanced OPO has been developed to provide excitation light from 3-4 µm at 140 mW with the ability to mode-hop tune continuously over 90 cm<sup>-1</sup> in 0.07 cm<sup>-1</sup> steps. Complementary use of both detection apparatus and excitation source has allowed for presence of ethane to be detected down to 200 parts per billion. Optics ; Materials science ; Interferometry ; Infrared ; Optoelectronics ; Thermal ; Physics Spectroscopy and Laser Applications ; Laser Design and Applications ; Advanced Fiber Laser Technologies
Authors: Fahimeh Sepehripour | Parisa Karimi | Amin Khavasi
Source: IET Optoelectronics (article, 2020-04-16)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Wideband and polarisation‐independent antireflection coating using metamaterials Here, the authors propose a new approach for realising wideband and polarisation‐independent antireflection coating, based on a metamaterial composed of a subwavelength array of metallic pillars with a square cross‐section. The effective impedance of the array can be duly adjusted by the size and distance of the pillars. As such, the authors design the effective impedance of the antireflection coating to be the geometrical mean of the impedance of upper and lower media and choose its height to be quarter of operating wavelength. Doing so, the reflection vanishes at the desired frequency and fractional bandwidth of 56% is achieved with a criterion of 10% reflectance (the refractive index of the substrate is assumed to be 4). Importantly, the proposed structure is symmetric in both directions. Thus, in contrast to prior arts, it is not sensitive to the polarisation of the incident wave at normal incidence. In addition to that, it is designed based on a multilayer Chebyshev matching transformer of transmission line theory, which potentially increases the bandwidth of the antireflection up to 107%, albeit at the expense of pass‐band ripples. This structure can be used from very low frequencies up to the infrared regime by appropriate scaling. Wideband ; Metamaterial ; Materials science ; Coating ; Tunable metamaterials ; Optoelectronics ; Optics ; Physics ; Composite material Metamaterials and Metasurfaces Applications ; Advanced Antenna and Metasurface Technologies ; Antenna Design and Analysis
Authors: Leandro Trupp | Andrea C. Bruttomesso | Mariana Vardé | Svetlana V. Eliseeva | Javier A. Ramírez | Stéphane Pètoud | Beatriz C. Barja
Source: Chemistry - A European Journal (article, 2020-09-22)
Field: Materials Science — Materials Chemistry

Innovative Multipodal Ligands Derived from Tröger's Bases for the Sensitization of Lanthanide(III) Luminescence Herein, the synthesis and characterization of the first family of multipodal ligands with a Tröger's base framework designed for the preparation of luminescent lanthanide(III) complexes are reported. Eight ligands were designed and synthesized using different strategies, including alkylation reactions, amide couplings, and Ugi multicomponent reactions. All the ligands bear carboxylate groups for the coordination of the lanthanide(III) ions, with the lanthanide(III)-sensitizing units consisting of the Tröger's base framework itself or attached benzamides. Upon irradiation of the chromophoric ligands, green terbium(III) emission was efficiently generated, whereas europium(III) emission was negligible. The geometry and substitution pattern of the ligands allow control of the stoichiometry of the species formed and the Tb<sup>III</sup> luminescence sensitization efficiency, showing that para-substitution patterns are more efficient than meta substitution for the formation of coordination compounds with lower Tb<sup>III</sup> /ligand ratio. We propose that the species formed are self-assembled 2:2 or 2:4 metallosupramolecular structures. Lanthanide ; Terbium ; Luminescence ; Chemistry ; Ligand (biochemistry) ; Europium ; Amide ; Carboxylate ; Stoichiometry ; Stereochemistry ; Combinatorial chemistry ; Ion ; Photochemistry ; Materials science ; Organic chemistry Lanthanide and Transition Metal Complexes ; Advanced NMR Techniques and Applications ; Magnetism in coordination complexes
Authors: Ireneusz Bugański | Janusz Wolny | Hiroyuki Takakura
Source: Acta Crystallographica Section A Foundations and Advances (article, 2020-02-11)
Field: Materials Science — Materials Chemistry

The atomic structure of the Bergman-type icosahedral quasicrystal based on the Ammann–Kramer–Neri tiling In this study, the atomic structure of the ternary icosahedral ZnMgTm quasicrystal (QC) is investigated by means of single-crystal X-ray diffraction. The structure is found to be a member of the Bergman QC family, frequently found in Zn-Mg-rare-earth systems. The ab initio structure solution was obtained by the use of the Superflip software. The infinite structure model was founded on the atomic decoration of two golden rhombohedra, with an edge length of 21.7 Å, constituting the Ammann-Kramer-Neri tiling. The refined structure converged well with the experimental diffraction diagram, with the crystallographic R factor equal to 9.8%. The Bergman clusters were found to be bonded by four possible linkages. Only two linkages, b and c, are detected in approximant crystals and are employed to model the icosahedral QCs in the cluster approach known for the CdYb Tsai-type QC. Additional short b and a linkages are found in this study. Short interatomic distances are not generated by those linkages due to the systematic absence of atoms and the formation of split atomic positions. The presence of four linkages allows the structure to be pictured as a complete covering by rhombic triacontahedral clusters and consequently there is no need to define the interstitial part of the structure (i.e. that outside the cluster). The 6D embedding of the solved structure is discussed for the final verification of the model. Quasicrystal ; Icosahedral symmetry ; Crystallography ; Cluster (spacecraft) ; Ternary operation ; Ab initio ; Crystal structure ; Type (biology) ; Diffraction ; Materials science ; Condensed matter physics ; Geometry ; Chemistry ; Physics ; Mathematics ; Quantum mechanics ; Computer science Quasicrystal Structures and Properties ; Mineralogy and Gemology Studies ; Archaeology and Rock Art Studies
Authors: A. Gorel | Marie Luise Grünbein | Richard Bean | Johan Bielecki | M. Hilpert | Michele Cascella | Jacques‐Philippe Colletier | Hans Fangohr | L. Foucar | Elisabeth Hartmann | Mark Hunter | Henry Kirkwood | Marco Kloos | Romain Letrun | Thomas Michelat | Robert L. Shoeman | J. Sztuk-Dambietz | Guillaume Tetreau | H. Zimmermann | Adrian P. Mancuso⋈ | Thomas R. M. Barends | R. Bruce Doak | Claudiu A. Stan | Ilme Schlichting
Source: Crystals (article, 2020-12-16)
Field: Materials Science — Materials Chemistry

Shock Damage Analysis in Serial Femtosecond Crystallography Data Collected at MHz X-ray Free-Electron Lasers Serial femtosecond crystallography (SFX) data were recorded at the European X-ray free-electron laser facility (EuXFEL) with protein microcrystals delivered via a microscopic liquid jet. An XFEL beam striking such a jet may launch supersonic shock waves up the jet, compromising the oncoming sample. To investigate this efficiently, we employed a novel XFEL pulse pattern to nominally expose the sample to between zero and four shock waves before being probed. Analyzing hit rate, indexing rate, and resolution for diffraction data recorded at MHz pulse rates, we found no evidence of damage. Notably, however, this conclusion could only be drawn after careful identification and assimilation of numerous interrelated experimental factors, which we describe in detail. Failure to do so would have led to an erroneous conclusion. Femtosecond photography of the sample-carrying jet revealed critically different jet behavior from that of all homogeneous liquid jets studied to date in this manner. Femtosecond ; Laser ; Optics ; Shock (circulatory) ; Shock wave ; Jet (fluid) ; Diffraction ; Materials science ; Supersonic speed ; Physics Enzyme Structure and Function ; Advanced X-ray Imaging Techniques ; Advanced Electron Microscopy Techniques and Applications
Authors: Marcus D. Hanwell | Chris Harris | Alessandro Genova | Mojtaba Haghighatlari | Muammar El Khatib | Patrick Avery | Johannes Hachmann | Wibe A. de Jong
Source:  (preprint, 2020-08-26)
Field: Materials Science — Materials Chemistry

Open Chemistry, JupyterLab, REST, and Quantum Chemistry Quantum chemistry must evolve if it wants to fully leverage the benefits of the internet age, where the world wide web offers a vast tapestry of tools that enable users to communicate and interact with complex data at the speed and convenience of a button press. The Open Chemistry project has developed an open source framework that offers an end-to-end solution for producing, sharing, and visualizing quantum chemical data interactively on the web using an array of modern tools and approaches. These tools build on some of the best open source community projects such as Jupyter for interactive online notebooks, coupled with 3D accelerated visualization, state-of-the-art computational chemistry codes including NWChem and Psi4 and emerging machine learning and data mining tools such as ChemML and ANI. They offer flexible formats to import and export data, along with approaches to compare computational and experimental data. Leverage (statistics) ; Computer science ; World Wide Web ; Visualization ; The Internet ; Open source ; Chemistry ; Data science ; Data mining ; Software ; Artificial intelligence Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Scientific Computing and Data Management
Authors: Aziza Hussien
Source: Egyptian Journal of Chemistry (article, 2020-05-15)
Field: Materials Science — Polymers and Plastics

Flame Resistance of Cotton Fabrics and Their Natural Dyeing Using Plant Waste of Banana Pseudostem (BPS) The present study has demonstrated the flame retardancy effect of Banana pseudostem (BPS) as plant wastes at different concentrations on bleached and mercerized Egyptian cotton fabric made of Giza 90. Alkaline method was used to produce the extract BPS. The cotton fabric after the treatment was found to produce stable natural semi kaki color. Flame retardant properties of both the untreated and the treated cotton fabrics were analyzed in terms of limiting oxygen index (LOI), horizontal and vertical flammability. The control and the treated cotton fabrics were examined using FTIR, thermo-gravimetric analysis, mechanical properties, and color components analysis. The results revealed that, the treated cotton fabrics were found to have good flame retardant property of LOI at BPS concentration 10% compared to the control fabrics. In the vertical flammability test, the treated fabric showed flame for a few seconds and then got extinguished. In the horizontal flammability test, the treated fabric showed no flame, but was burning with a propagation rate of 7.5 mm/min, which was almost 10 times lower than that noted with the control fabric. The results revealed that, there was no significant degradation in mechanical strengths. Based on the results, the mechanisms of formation of natural color on the cotton fabrics using the proposed BPS treatments have been postulated. Dyeing ; Pulp and paper industry ; Waste management ; Materials science ; Horticulture ; Environmental science ; Composite material ; Engineering ; Biology Flame retardant materials and properties ; Natural Fiber Reinforced Composites ; Dyeing and Modifying Textile Fibers
Authors: Zhaoliang Xing | Chong Zhang | Mingsheng Fan | Pengfei Wu | Xin Chen | Zhonglei Li
Source: IEEE Access (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Trap Level Characteristics and DC Breakdown Performance of Isotactic/Syndiotactic/Atactic Polypropylene Blend Insulation Polypropylene (PP) material as a DC cable insulation material has great prospects as a recyclable alternative to cross-linked polyethylene. This paper aims at investigate the effect of PP blends crystallinity morphology and trap energy level distribution on DC breakdown strength. Five different ratios iPP/sPP/aPP blends samples are prepared by melt-blending method. Polarizing optical microscope (POM) experiments are conducted to characterize the crystallinity morphology of five iPP/sPP/aPP blends and isothermal surface potential decay (ISPD) methods are employed to measure the trap levels distribution in composite dielectric. The DC breakdown strength is tested by ball-plate electrodes equipment, and the result of DC breakdown experiment indicates that sPP30 exhibits the highest breakdown field strength, which is 29.2% higher than sPP0. The addition of sPP can act as a nucleus to help the crystallization behavior of iPP, and the distribution of spherulites in sPP30 is the most uniform and dense among the five iPP/sPP/aPP blends samples, which can improve the trap characteristics of polymers. The ISPD results show that the decay rate of the sPP30 sample is the slowest at 50 °C, 70 °C and 90 °C, indicating that sPP30 is more conducive to suppressing the dissipation process of carriers during the depolarization process. Moreover, sPP30 has higher deep trap density and lower shallow trap density and exhibits superior breakdown performance. It is deduced that the addition of sPP can effectively regulate the crystallinity morphology of iPP, and then effectively improve the trap energy level distribution of iPP/sPP/aPP blends, and it shows the improvement of DC breakdown performance macroscopically. Materials science ; Crystallinity ; Composite material ; Polypropylene ; Tacticity ; Polyethylene ; Crystallization ; Isothermal process ; Dielectric ; Polymer ; Chemical engineering ; Polymerization ; Optoelectronics High voltage insulation and dielectric phenomena ; Dielectric materials and actuators ; Electrostatic Discharge in Electronics
Authors: Abdelrahman Said | Amira G. Nawar | Elsayed Alaa Eldesoky | Samir Kamel | Mousa A. Abd‐Allah
Source: American Journal of Polymer Science and Technology (article, 2020-01-01)
Field: Materials Science — Materials Chemistry

Enhancing the High Voltage XLPE Cable Insulation Characteristics Using Functionalized TiO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; Nanoparticles The current research aims to study the influence of loading Titanium Dioxide (TiO<sub>2</sub>) nanoparticles on the dielectric, thermal and mechanical properties of the commercial Cross-Linked Polyethylene (XLPE) used as the main insulation in power cables. Using the concept of composite, XLPE/TiO<sub>2</sub> nanocomposites samples were prepared by the melt blending method with different ratios of nanoparticles (0.5, 2, 3.5 and 5% wt/wt). The surface treatment of TiO<sub>2</sub> nanoparticles was carried out to reduce the agglomeration of TiO<sub>2</sub> nanoparticles inside the XLPE. The morphology of the prepared samples was studied by X-ray Diffraction (XRD) and the dispersion of nanoparticles in the XLPE polymer matrix is checked using Field Emission Scanning Electron Microscopy (FE-SEM). Thermal analysis test for all samples have been investigated. The dielectric properties, such as dielectric constant (ε<sub>r</sub>) and loss tangent (tan δ) for XLPE/TiO<sub>2</sub> nanocomposites were measured under frequencies ranging from 1 Hz to 1 MHz. AC Breakdown Voltage (AC-BDV) was also measured using a controlled high voltage testing transformer (50 Hz) under sphere-to-sphere field. The mechanical properties were evaluated by performing the tensile test and tensile strength and elongation values were measured. It was found that nanocomposites with functionalized TiO<sub>2</sub> exhibited better dielectric, thermal and mechanical properties compared to nanocomposites with nonfunctionalized TiO<sub>2</sub>. Materials science ; Dielectric ; Composite material ; Nanocomposite ; Ultimate tensile strength ; Dissipation factor ; Nanoparticle ; Polyethylene ; Scanning electron microscope ; Dielectric loss ; Polymer ; Nanotechnology High voltage insulation and dielectric phenomena ; Thermal Analysis in Power Transmission ; Life Cycle Costing Analysis
Authors: Eduard Massaguer | A. Massaguer | Eudald Balló | I.R. Cózar | Toni Pujol | L. Montoro | M. Comamala
Source: Energies (article, 2020-07-02)
Field: Materials Science — Materials Chemistry

Electrical Generation of a Ground-Level Solar Thermoelectric Generator: Experimental Tests and One-Year Cycle Simulation Solar thermoelectric generators (STEGs) are a promising technology to harvest energy for off-grid applications. A wide variety of STEG designs have been proposed with the aim of providing non-intermittent electrical generation. Here, we designed and tested a STEG 0.5 m long formed by nine commercial thermoelectric generator modules and located at ground level. Data were used to validate a numerical model that was employed to simulate a one-year cycle. Results confirmed the very high variability of energy generation during daylight time due to weather conditions. By contrast, energy generation during night was almost independent of atmospheric conditions. Annual variations of nighttime energy generation followed the trend of the daily averaged soil temperature at the bottom of the device. Nighttime electrical energy generation was 5.4 times smaller than the diurnal one in yearly averaged values. Mean energy generation values per day were 587 J d−1 (daylight time) and 110 J d−1 (nighttime). Total annual energy generation was 255 kJ. Mean electrical output power values during daylight and nighttime were 13.4 mW and 2.5 mW, respectively. Annual mean output power was 7.9 mW with a peak value of 79.8 mW. Electricity generation ; Environmental science ; Daylight ; Thermoelectric generator ; Electric potential energy ; Meteorology ; Thermoelectric effect ; Electric power ; Solar energy ; Atmospheric sciences ; Daytime ; Energy (signal processing) ; Power (physics) ; Electrical engineering ; Engineering ; Physics ; Mathematics ; Statistics ; Optics Advanced Thermoelectric Materials and Devices ; Thermal Radiation and Cooling Technologies ; Innovative Energy Harvesting Technologies