Atomistic modelling insight into the structure of lignite-based activated carbon and benzene sorption behavior

RSC Advances ◽  
2016 ◽  
Vol 6 (61) ◽  
pp. 56623-56637 ◽  
Author(s):  
Yang Huang ◽  
Fred S. Cannon ◽  
Jinsong Guo ◽  
Justin K. Watson ◽  
Jonathan P. Mathews
Keyword(s):  
Activated Carbon ◽  
Large Scale ◽  
Structural Models ◽  
Sorption Behavior ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Atomistic Modelling ◽  
Insight Into

Improved structure–property relationships for activated carbon were obtained by devising realistic, large-scale, structural models.

Quantitative structure property relationships for the adsorption of pharmaceuticals onto activated carbon

2010 ◽  
Vol 62 (10) ◽  
pp. 2270-2276 ◽  
Author(s):  
E. R. V. Dickenson ◽  
J. E. Drewes
Keyword(s):  
Activated Carbon ◽  
Pure Water ◽  
Freundlich Isotherm ◽  
Sorption Behavior ◽  
Quantitative Structure ◽  
Structure Property ◽  
Hydrogen Bond Donor ◽  
Structure Property Relationships ◽  
Quantitative Structure Property Relationships ◽  
Energy Relationships

Isotherms were determined for the adsorption of five pharmaceutical residues, primidone, carbamazepine, ibuprofen, naproxen and diclofenac, to Calgon Filtrasorb 300 powdered activated carbon (PAC). The sorption behavior was examined in ultra-pure and wastewater effluent organic matter (EfOM) matrices, where more sorption was observed in the ultra-pure water for PAC doses greater than 10 mg/L suggesting the presence of EfOM hinders the sorption of the pharmaceuticals to the PAC. Adsorption behaviors were described by the Freundlich isotherm model. Quantitative structure property relationships (QSPRs) in the form of polyparameter linear solvation energy relationships were developed for simulating the Freundlich adsorption capacity in both ultra-pure and EfOM matrices. The significant 3D-based descriptors for the QSPRs were the molar volume, polarizability and hydrogen-bond donor parameters.

Structure/Property Relationships of Seashells

2004 ◽  
Vol 844 ◽  
Author(s):  
David J. Scurr ◽  
Stephen J. Eichhorn
Keyword(s):  
Raman Band ◽  
Surface Damage ◽  
Structure Property ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Property Relationships ◽  
Energy Variable ◽  
Insight Into ◽  
Characterisation Techniques ◽  
Scanning Electron

ABSTRACTThis study uses various characterisation techniques on the razor shell (Ensis siliqua), to relate the shell's microstructure to its mechanical properties. Scanning electron microscopy (SEM) has shown that the outer and inner regions of the shell are composed of simple and complex crossed lamellar microstructures respectively. These layers are interspersed by prismatic layers of a completely different crystallographic orientation. Nanoindentation and microhardness measurements have shown that the structure is anisotropic, and Raman band shifts have been observed within these indented/deformed areas of shell, showing that the microstructure deforms rather than generating surface damage. The use of energy variable synchrotron X-ray diffraction has shown that the calcium carbonate crystals of the shell are preferentially orientated as a function of depth and that opposing residual stresses exist at the outer and inner regions of the shell. This study has analysed several microstructural features of the shell and provided an insight into how they prevent failure of the material.

Crystal and electronic structure of the new ternary phosphide Ho5Pd19P12

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Olha Zhak ◽  
Oksana Karychort ◽  
Volodymyr Babizhetskyy ◽  
Chong Zheng
Keyword(s):  
Crystal Structure ◽  
Electronic Structure ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Structure Property ◽  
X Ray Diffraction ◽  
Structure Property Relationships ◽  
Metallic Bonding ◽  
Crystal And Electronic Structure ◽  
Insight Into

Abstract The title compound was prepared from the pure elements by sintering. The crystal structure was investigated by means of powder X-ray diffraction data. Ho5Pd19P12 exhibits the hexagonal Ho5Ni19P12-type structure with space group P 6 ‾ 2 m $P‾{6}2m$ , a = 13.1342(2), c = 3.9839(1) Å, R I = 0.060, R p = 0.080. The crystal structure can be described as a combination of two types of the structural units, [HoPd6P3] and [Ho3Pd10P6], respectively, mutually displaced by 1/2 along the crystallographic c axis. Quantum chemical calculations have been performed to analyze the electronic structure and provide deeper insight into the structure-property relationships. The results of the quantum chemical calculations indicate that the material features metallic bonding between Ho and Pd and covalent bonding between Pd and P.

Efficiently mapping structure–property relationships of gas adsorption in porous materials: application to Xe adsorption

2017 ◽  
Vol 201 ◽  
pp. 221-232 ◽  
Author(s):  
A. R. Kaija ◽  
C. E. Wilmer
Keyword(s):  
Porous Materials ◽  
Void Fraction ◽  
Large Scale ◽  
Gas Adsorption ◽  
Structural Characteristics ◽  
Gas Storage ◽  
Computational Method ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Computational Screening

Designing better porous materials for gas storage or separations applications frequently leverages known structure–property relationships. Reliable structure–property relationships, however, only reveal themselves when adsorption data on many porous materials are aggregated and compared. Gathering enough data experimentally is prohibitively time consuming, and even approaches based on large-scale computer simulations face challenges. Brute force computational screening approaches that do not efficiently sample the space of porous materials may be ineffective when the number of possible materials is too large. Here we describe a general and efficient computational method for mapping structure–property spaces of porous materials that can be useful for adsorption related applications. We describe an algorithm that generates random porous “pseudomaterials”, for which we calculate structural characteristics (e.g., surface area, pore size and void fraction) and also gas adsorption properties via molecular simulations. Here we chose to focus on void fraction and Xe adsorption at 1 bar, 5 bar, and 10 bar. The algorithm then identifies pseudomaterials with rare combinations of void fraction and Xe adsorption and mutates them to generate new pseudomaterials, thereby selectively adding data only to those parts of the structure–property map that are the least explored. Use of this method can help guide the design of new porous materials for gas storage and separations applications in the future.

Influence of Structural Organization On Optical and Transport Properties in Organic Materials

1999 ◽  
Vol 598 ◽  
Author(s):  
J. Cornil ◽  
J.Ph. Calbert ◽  
D. Beljonne ◽  
D.A. Dos Santos ◽  
J.L. Bredas
Keyword(s):  
Transport Properties ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Structural Organization ◽  
Conjugated Oligomers ◽  
Structure Property ◽  
Chain Packing ◽  
Crystalline Phases ◽  
Structure Property Relationships ◽  
Insight Into

ABSTRACTCorrelated quantum-chemical calculations performed on supermolecular structures, i.e., on clusters made of several oligomer chains in interaction, provide insight into structure-property relationships in well-organized molecular films. This supermolecular approach is applied to crystalline phases of two prototypical conjugated oligomers and shows that variations in chain packing can lead to dramatically different optical (Davydov) splittings and carrier mobilities. Optimal chain organizations for various types of devices are discussed.

scholarly journals Towards low-energy-light-driven bistable photoswitches: ortho-fluoroaminoazobenzenes

2021 ◽  
Author(s):  
Kim Kuntze ◽  
Jani Viljakka ◽  
Evgenii Titov ◽  
Zafar Ahmed ◽  
Elina Kalenius ◽  
...  
Keyword(s):  
Visible Light ◽  
Excited States ◽  
Quantum Chemical ◽  
Low Energy ◽  
Living Systems ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Thermal Stability Of ◽  
Insight Into ◽  
Cis Isomer

Abstract Thermally stable photoswitches that are driven with low-energy light are rare, yet crucial for extending the applicability of photoresponsive molecules and materials towards, e.g., living systems. Combined ortho-fluorination and -amination couples high visible-light absorptivity of o-aminoazobenzenes with the extraordinary bistability of o-fluoroazobenzenes. Herein, we report a library of easily accessible o-aminofluoroazobenzenes and establish structure–property relationships regarding spectral qualities, visible light isomerization efficiency and thermal stability of the cis-isomer with respect to the degree of o-substitution and choice of amino substituent. We rationalize the experimental results with quantum chemical calculations, revealing the nature of low-lying excited states and providing insight into thermal isomerization. The synthesized azobenzenes absorb at up to 600 nm and their thermal cis-lifetimes range from milliseconds to months. The most unique example can be driven from trans to cis with any wavelength from UV up to 595 nm, while still exhibiting a thermal cis-lifetime of 81 days.

When Current Does Not Follow Bonds: Current Density in Saturated Molecules

2019 ◽  
Author(s):  
Anders Jensen ◽  
Marc Hamilton Garner ◽  
Gemma C. Solomon
Keyword(s):  
Spatial Distribution ◽  
Current Density ◽  
Current Flow ◽  
Structure Property ◽  
Conjugated Molecules ◽  
Structure Property Relationships ◽  
Electron Transport Properties ◽  
Current Flows ◽  
Molecular Conductance ◽  
Insight Into

<div> <div> <div> <p>The tools commonly used to understand structure-property relationships in molecular conductance, inter-atomic currents and conductance eigenchannels, generally give us a sense of familiarity, with the chemical bonding framework and molecular orbitals reflected in the current. Here we show that while this picture is true for conjugated molecules, it breaks down in saturated systems. We investigate the current density in saturated chains of alkanes, silanes and germanes and show that the current density does not follow the bonds, but rather the nuclei define the diameter of a pipe through which the current flows. We discuss how this picture of current density can be used to understand details about the electron transport properties of these molecules. Understanding the spatial distribution of current through molecules, rather than simply the magnitude, provides a powerful tool for chemical insight into physical properties of molecules that are related to current flow. </p> </div> </div> </div>

scholarly journals GaAs Nanowires Grown by Catalyst Epitaxy for High Performance Photovoltaics

Crystals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 347 ◽  
Author(s):  
Ying Wang ◽  
Xinyuan Zhou ◽  
Zaixing Yang ◽  
Fengyun Wang ◽  
Ning Han ◽  
...  
Keyword(s):  
Light Absorption ◽  
High Performance ◽  
Large Scale ◽  
Low Cost ◽  
Absorption Efficiency ◽  
Device Fabrication ◽  
Structure Property ◽  
Structure Property Relationships ◽  
Solar Energy Harvesting ◽  
Gaas Nanowire

Photovoltaics (PVs) based on nanostructured III/V semiconductors can potentially reduce the material usage and increase the light-to-electricity conversion efficiency, which are anticipated to make a significant impact on the next-generation solar cells. In particular, GaAs nanowire (NW) is one of the most promising III/V nanomaterials for PVs due to its ideal bandgap and excellent light absorption efficiency. In order to achieve large-scale practical PV applications, further controllability in the NW growth and device fabrication is still needed for the efficiency improvement. This article reviews the recent development in GaAs NW-based PVs with an emphasis on cost-effectively synthesis of GaAs NWs, device design and corresponding performance measurement. We first discuss the available manipulated growth methods of GaAs NWs, such as the catalytic vapor-liquid-solid (VLS) and vapor-solid-solid (VSS) epitaxial growth, followed by the catalyst-controlled engineering process, and typical crystal structure and orientation of resulted NWs. The structure-property relationships are also discussed for achieving the optimal PV performance. At the same time, important device issues are as well summarized, including the light absorption, tunnel junctions and contact configuration. Towards the end, we survey the reported performance data and make some remarks on the challenges for current nanostructured PVs. These results not only lay the ground to considerably achieve the higher efficiencies in GaAs NW-based PVs but also open up great opportunities for the future low-cost smart solar energy harvesting devices.

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