Assessing the effect of pyrolysis temperature on the molecular properties and copper sorption capacity of a halophyte biochar

Biochar was derived from MgCl2 and MgO pretreated sawdust and corn husks at 300 °C and 600 °C, respectively, to investigate the effects of exogenous minerals on the stability and sorption performance of the resulting biochar. Impregnation with Mg decreased carbon concentration, increased yield and ash concentration, and increased the pH values at the point of zero charge (pHPZC) of the resulting biochar. The chemical stability of biochar oxidized by K2CrO7 was enhanced with increasing pyrolysis temperature and decreased with the pretreatment of MgCl2 and MgO. Mg-impregnation enhanced carbon loss of the resulting biochar and increased the sorption capacity of biochar for CR significantly, which is potentially caused by electrostatic interaction and surface complexation. This study indicates that magnesium-impregnation significantly enhances the sorption performance of anionic contaminants and the pyrolysis temperature has a greater effect on the stability of the resulting biochar than the magnesium-impregnation.

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Response Theory and Molecular Properties (A Tribute to Jan Linderberg and Poul Jørgensen)

10.1016/s0065-3276(05)x5000-6 ◽

2005 ◽

Keyword(s):

Molecular Properties ◽

Response Theory

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Theoretical study of C60O2 molecular properties

Journal of Molecular Structure THEOCHEM ◽

10.1016/s0166-1280(96)04855-5 ◽

1997 ◽

Vol 392 (1) ◽

pp. 217-221 ◽

Cited By ~ 1

Author(s):

S Zhenfeng

Keyword(s):

Theoretical Study ◽

Molecular Properties

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MOLECULAR PROPERTIES OF SOME NEMATIC LIQUIDS. I. MAGNETIC SUSCEPTIBILITY ANISOTROPY AND ORDER PARAMETER

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1979333 ◽

1979 ◽

Vol 40 (C3) ◽

pp. C3-164-C3-168 ◽

Cited By ~ 17

Author(s):

I. H. IBRAHIM ◽

W. HAASE

Keyword(s):

Magnetic Susceptibility ◽

Order Parameter ◽

Molecular Properties ◽

Magnetic Susceptibility Anisotropy

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The Influences of the Rank of Coal on Methane Sorption Capacity in Coals/Wpływ Rzędu Węgla Na Pojemność Sorpcyjną Metanu W Węglach

Archives of Mining Sciences ◽

10.2478/amsc-2014-0037 ◽

2014 ◽

Vol 59 (2) ◽

pp. 509-516

Author(s):

Andrzej Olajossy

Keyword(s):

Sorption Capacity ◽

Coalbed Methane ◽

Vitrinite Reflectance ◽

Sorption Isotherms ◽

Volatile Matter ◽

Low Rank ◽

Hard Coal ◽

Petrographic Composition ◽

Methane Sorption ◽

Indian Coals

Abstract Methane sorption capacity is of significance in the issues of coalbed methane (CBM) and depends on various parameters, including mainly, on rank of coal and the maceral content in coals. However, in some of the World coals basins the influences of those parameters on methane sorption capacity is various and sometimes complicated. Usually the rank of coal is expressed by its vitrinite reflectance Ro. Moreover, in coals for which there is a high correlation between vitrinite reflectance and volatile matter Vdaf the rank of coal may also be represented by Vdaf. The influence of the rank of coal on methane sorption capacity for Polish coals is not well understood, hence the examination in the presented paper was undertaken. For the purpose of analysis there were chosen fourteen samples of hard coal originating from the Upper Silesian Basin and Lower Silesian Basin. The scope of the sorption capacity is: 15-42 cm3/g and the scope of vitrinite reflectance: 0,6-2,2%. Majority of those coals were of low rank, high volatile matter (HV), some were of middle rank, middle volatile matter (MV) and among them there was a small number of high rank, low volatile matter (LV) coals. The analysis was conducted on the basis of available from the literature results of research of petrographic composition and methane sorption isotherms. Some of those samples were in the form (shape) of grains and others - as cut out plates of coal. The high pressure isotherms previously obtained in the cited studies were analyzed here for the purpose of establishing their sorption capacity on the basis of Langmuire equation. As a result of this paper, it turned out that for low rank, HV coals the Langmuire volume VL slightly decreases with the increase of rank, reaching its minimum for the middle rank (MV) coal and then increases with the rise of the rank (LV). From the graphic illustrations presented with respect to this relation follows the similarity to the Indian coals and partially to the Australian coals.

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A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

10.26434/chemrxiv.11320130.v1 ◽

2019 ◽

Cited By ~ 2

Author(s):

Tian Lu ◽

Qinxue Chen ◽

Zeyu Liu

Keyword(s):

Molecular Dynamics ◽

Excited States ◽

Electronic Excitation ◽

Ring Structure ◽

Molecular Properties ◽

Molecular Vibration ◽

Full Characterization ◽

Long Time ◽

Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., Science, 365, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

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A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

10.26434/chemrxiv.11320130 ◽

2019 ◽

Cited By ~ 2

Author(s):

Tian Lu ◽

Qinxue Chen ◽

Zeyu Liu

Keyword(s):

Molecular Dynamics ◽

Excited States ◽

Electronic Excitation ◽

Ring Structure ◽

Molecular Properties ◽

Molecular Vibration ◽

Full Characterization ◽

Long Time ◽

Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., Science, 365, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

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Accurate and Transferable Multitask Prediction of Chemical Properties with an Atoms-in-Molecule Neural Network

10.26434/chemrxiv.7151435.v2 ◽

2018 ◽

Author(s):

Roman Zubatyuk ◽

Justin S. Smith ◽

Jerzy Leszczynski ◽

Olexandr Isayev

Keyword(s):

Neural Network ◽

Molecular System ◽

Computational Cost ◽

Chemical Properties ◽

The State ◽

Molecular Properties ◽

Training Data ◽

Dft Methods ◽

Benchmark Datasets ◽

Quantum Phenomena

Atomic and molecular properties could be evaluated from the fundamental Schrodinger’s equation and therefore represent different modalities of the same quantum phenomena. Here we present AIMNet, a modular and chemically inspired deep neural network potential. We used AIMNet with multitarget training to learn multiple modalities of the state of the atom in a molecular system. The resulting model shows on several benchmark datasets the state-of-the-art accuracy, comparable to the results of orders of magnitude more expensive DFT methods. It can simultaneously predict several atomic and molecular properties without an increase in computational cost. With AIMNet we show a new dimension of transferability: the ability to learn new targets utilizing multimodal information from previous training. The model can learn implicit solvation energy (like SMD) utilizing only a fraction of original training data, and archive MAD error of 1.1 kcal/mol compared to experimental solvation free energies in MNSol database.

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