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1. Incorporation of Rare Earths and Yttrium in Calcite: A Critical Re-evaluation

Author:
Möller, Peter; De Lucia, Marco
Source:
Aquatic geochemistry 2020 v.26 no.2 pp. 89-117
ISSN:
1380-6165
Subject:
partition coefficients,   etc   ; calcite; calcium; carbonates; geochemistry; magnesium; seawater; yttrium;     Show all 8 Subjects
Abstract:
... The reported partition coefficients of REE with calcite are reviewed and critically discussed. In some of the reported experimental sets, REE concentrations are found to be supersaturated with respect to individual REE₂(CO₃)₃ but never to REE(OH)₃. Although the solutions are unsaturated with respect to individual REY carbonates, REY including Y are incorporated in calcite surfaces, where they are ...
DOI:
10.1007/s10498-020-09369-9

2. The magmatic and magmatic-hydrothermal evolution of felsic igneous rocks as seen through Nb-Ta geochemical fractionation, with implications for the origins of rare-metal mineralizations

Author:
Ballouard, Christophe; Massuyeau, Malcolm; Elburg, Marlina A.; Tappe, Sebastian; Viljoen, Fanus; Brandenburg, Jean-Tristan
Source:
Earth-science reviews 2020 v.203 pp. 103115
ISSN:
0012-8252
Subject:
partition coefficients,   etc   ; biotite; crystallization; fractionation; igneous rocks; mineralization; regression analysis;     Show all 7 Subjects
Abstract:
... Despite Nb and Ta being considered as ‘geochemical twins’, most Ta mineral deposits are associated with muscovite-bearing peraluminous granites and related pegmatites (MPG), whereas significant Nb deposits are related to peralkaline to metaluminous A1-type granites and syenites as well as nepheline syenites. Metaluminous to peraluminous A2-type granites and syenites have a lower potential for rare ...
DOI:
10.1016/j.earscirev.2020.103115

3. Adsorption of nitrogen-containing compounds on hydroxylated α-quartz surfaces

Author:
Tsendra, Oksana; Boese, A. Daniel; Isayev, Olexandr; Gorb, Leonid; Scott, Andrea Michalkova; Hill, Frances C.; Ilchenko, Mykola M.; Lobanov, Victor; Leszczynska, Danuta; Leszczynski, Jerzy
Source:
RSC advances 2019 v.9 no.62 pp. 36066-36074
ISSN:
2046-2069
Subject:
partition coefficients,   etc   ; adsorption; hydroxylation; trinitrotoluene;     Show all 4 Subjects
Abstract:
... Adsorption energies of various nitrogen-containing compounds (specifically, 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), 2,4-dinitroanisole (DNAn), and 3-nitro-1,2,4-triazole-5-one (NTO)) on the hydroxylated (001) and (100) α-quartz surfaces are computed. Different density functionals are utilized and both periodic as well as cluster approaches are applied. From the adsorption energies, ...
DOI:
10.1039/c9ra07130j

4. Lipophilicity assessment of some isoniazid derivatives active against Mycobacterium tuberculosis

Author:
Santos, M. Soledade C.S.; Matos, Ana Marta; Reis, Marina; Martins, Filomena
Source:
Colloids and surfaces 2020 v.599 pp. 124820
ISSN:
0927-7757
Subject:
partition coefficients,   etc   ; Mycobacterium tuberculosis; bioactive properties; culture flasks; hydrophobicity; ionic strength; isoniazid; lipophilicity; pH; spectroscopy;     Show all 10 Subjects
Abstract:
... Micelle-water partition coefficients, log Kₚ₍NₐDS/w₎, and octanol-water partition coefficients,log Pₒ/w, for 9 isoniazid derivatives, previously assessed as active against Mycobacterium tuberculosis, were determined using derivative spectrophotometry and the shake flask method in buffer systems at adequate pH values and ionic strength (0.1 M).Most of the compounds conform to a linear dependence be ...
DOI:
10.1016/j.colsurfa.2020.124820

5. Computational fluid dynamics prediction of formaldehyde emission and sorption processes in a small test chamber with mixing fan and vents

Author:
Mu, Yu-Tong; Li, Zi-Ai; Gu, Zhao-Lin; Tao, Wen-Quan
Source:
Atmospheric environment 2020 v.229 pp. 117455
ISSN:
1352-2310
Subject:
partition coefficients,   etc   ; adsorption; atmospheric chemistry; desorption; diffusivity; formaldehyde; mass transfer; mixing; particleboards; prediction;     Show all 10 Subjects
Abstract:
... Characterizing the emission performance of formaldehyde is critical for control strategies. Most previous emission models assume that formaldehyde concentrations are well-mixed. In this study, a computational fluid dynamics-based model is developed for simulating the mass transfer and adsorption/desorption processes of formaldehyde from particleboards in a chamber with a mixing fan. Numerical inve ...
DOI:
10.1016/j.atmosenv.2020.117455

6. A general linear free energy relationship for predicting partition coefficients of neutral organic compounds

Author:
Chen, Deliang; Wang, Qingyun; Li, Yibao; Li, Yongdong; Zhou, Hui; Fan, Yulan
Source:
Chemosphere 2020 v.247 pp. 125869
ISSN:
0045-6535
Subject:
partition coefficients,   etc   ; Gibbs free energy; environmental science; human health; models; organic compounds; prediction; solutes; solvents;     Show all 9 Subjects
Abstract:
... Predicting the effects of organic compounds on environments and biological systems is an important objective for environmental chemistry and human health. The logarithm (to base 10) of the n-octanoll–water partition coefficient has been widely used to predict the mentioned properties. However, the suitability of this parameter for the purpose has been questioned, since the environments relating to ...
DOI:
10.1016/j.chemosphere.2020.125869

7. Classification of biphasic solvent systems according to Abraham descriptors for countercurrent chromatography

Author:
Marlot, Léa; Batteau, Magali; Faure, Karine
Source:
Journal of chromatography 2020 v.1617 pp. 460820
ISSN:
0021-9673
Subject:
partition coefficients,   etc   ; countercurrent chromatography; ethyl acetate; heptane; methanol; models; prediction; solutes; solvation; solvents;     Show all 10 Subjects
Abstract:
... The method development of liquid-liquid chromatography, either countercurrent chromatography or centrifugal partition chromatography, is slowed down by the selection of the biphasic solvent system that constitutes its column. This paper introduces a classification of 19 solvent systems, including the most popular systems based on heptane/ethyl acetate/methanol/water, some non-aqueous systems and s ...
DOI:
10.1016/j.chroma.2019.460820

8. QSPR versus fragment-based methods to predict octanol-air partition coefficients: Revisiting a recent comparison of both approaches

Author:
Mathieu, Didier
Source:
Chemosphere 2020 v.245 pp. 125584
ISSN:
0045-6535
Subject:
partition coefficients,   etc   ; models; organic compounds; quantitative structure-activity relationships; quantum mechanics; solvation; temperature;     Show all 7 Subjects
Abstract:
... The octanol-air partition coefficient (KOA) is useful to assess the fate of organic chemicals in the environment. Very recently, an interesting comparison of current methods to predict this property (Chemosphere 148 (2016) 118–125) highlighted a newly introduced Quantitative Structure−Property Relationship (QSPR), as a group-contribution (GC) method and a quantum chemical solvation model were repo ...
DOI:
10.1016/j.chemosphere.2019.125584

9. Effects of suspended sediment on POCIS sampling rates

Author:
Djomte, Valerie Toteu; Chen, Sunmao; Chambliss, C. Kevin
Source:
Chemosphere 2020 v.241 pp. 124972
ISSN:
0045-6535
Subject:
partition coefficients,   etc   ; chemical species; pesticides; samplers; sediments; sorbents; suspended sediment; temperature; total suspended solids;     Show all 9 Subjects
Abstract:
... Effects of chemical uptake onto polar organic chemical integrative samplers (POCIS) exposed to total suspended solid (TSS) sediment concentrations of 0 and 3600 ppm were investigated for 12 pesticides at constant concentration, temperature, and flow velocity. The effects of sediment exposure on POCIS uptake were negligible for compounds with polyethersulfone-water partition coefficients greater th ...
DOI:
10.1016/j.chemosphere.2019.124972

10. Evidence for a kinetically controlled burying mechanism for growth of high viscosity secondary organic aerosol

Author:
Vander Wall, Allison C.; Perraud, Véronique; Wingen, Lisa M.; Finlayson-Pitts, Barbara J.
Source:
Environmental science 2020 v.22 no.1 pp. 66-83
ISSN:
2050-7895
Subject:
partition coefficients,   etc   ; Fourier transform infrared spectroscopy; aerosols; alpha-pinene; climate; nitrates; ozonolysis; prediction; reflectance; viscosity;     Show all 10 Subjects
Abstract:
... Secondary organic aerosol (SOA) particles are ubiquitous in air and understanding the mechanism by which they grow is critical for predicting their effects on visibility and climate. The uptake of three organic nitrates into semi-solid SOA particles formed by α-pinene ozonolysis either with or without an OH scavenger was investigated. Four types of experiments are presented here. In Series A, upta ...
DOI:
10.1039/c9em00379g

11. Predicting Partition Coefficients of Neutral and Charged Solutes in the Mixed SLES–Fatty Acid Micellar System

Author:
Turchi, Mattia; Kognole, Abhishek A.; Kumar, Anmol; Cai, Qiong; Lian, Guoping; MacKerell, Alexander D.
Source:
TheJournal of physical chemistry 2020 v.124 no.9 pp. 1653-1664
ISSN:
1520-5207
Subject:
partition coefficients,   etc   ; cosmetics; fatty acids; ingredients; micelles; molecular dynamics; prediction; sodium; solutes; sulfates;     Show all 10 Subjects
Abstract:
... Sodium laureth sulfate (SLES) and fatty acids are common ingredients in many cosmetic products. Understanding how neutral and charged fatty acid compounds partition between micellar and water phases is crucial to achieve the optimal design of the product formulation. In this paper, we first study the formation of mixed SLES and fatty acid micelles using molecular dynamics (MD) simulations. Micelle ...
DOI:
10.1021/acs.jpcb.9b11199
PubMed:
31955574
PubMed Central:
PMC7060100

12. Correction: Brønsted acid mediated covalent organic framework membranes for efficient molecular separation

Author:
Wang, Hongjian; Chen, Long; Yang, Hao; Wang, Meidi; Yang, Leixin; Du, Haiyan; Cao, Chenliang; Ren, Yanxiong; Wu, Yingzhen; Pan, Fusheng; Jiang, Zhongyi
Source:
Journal of materials chemistry A 2019 v.7 no.47 pp. 27186
ISSN:
2050-7496
Subject:
partition coefficients,   etc   ; Bronsted acids; chemical bonding; polymerization;     Show all 4 Subjects
Abstract:
... Correction for ‘Brønsted acid mediated covalent organic framework membranes for efficient molecular separation’ by Hongjian Wang et al., J. Mater. Chem. A, 2019, 7, 20317–20324. ...
DOI:
10.1039/c9ta90281c

13. Modeling of closed-loop recycling dual-mode counter-current chromatography based on non-ideal recycling model

Author:
Kostanyan, Artak E.; Galieva, Zhanetta N.
Source:
Journal of chromatography 2019 v.1603 pp. 240-250
ISSN:
0021-9673
Subject:
partition coefficients,   etc   ; countercurrent chromatography; equations; models; solutes;     Show all 5 Subjects
Abstract:
... Closed-loop recycling dual-mode counter-current chromatography (CLR DM CCC) includes two separation stages: 1 – closed-loop recycling separation of solutes with mobile x-phase (CLR CCC); 2 – separation of solutes with the mobile y-phase in the opposite flow direction. Previous analysis of CLR DM CCC separations has been limited to the ideal recycling model, which neglects extra-column dispersion. ...
DOI:
10.1016/j.chroma.2019.06.024

14. Salt-containing aqueous two-phase system shows predictable partition of proteins with surface amino acids residues

Author:
Shibata, Chika; Iwashita, Kazuki; Shiraki, Kentaro
Source:
International journal of biological macromolecules 2019 v.133 pp. 1182-1186
ISSN:
0141-8130
Subject:
partition coefficients,   etc   ; amino acids; ions; proteins; salts;     Show all 5 Subjects
Abstract:
... Aqueous two-phase system (ATPS) containing salts has been used for protein purification and enrichment. However, it is unclear how proteins are partitioned in the top or bottom phases of the system. In this study, we demonstrate that the partition of proteins in salt-containing ATPS (SATPS) depends only on the relation between the protein-surface amino acids and the type of salt using SATPS. The p ...
DOI:
10.1016/j.ijbiomac.2019.04.185

15. Closed-loop recycling dual-mode counter-current chromatography. A theoretical study

Author:
Kostanyan, Artak E.; Belova, Vera V.
Source:
Journal of chromatography 2019 v.1588 pp. 174-179
ISSN:
0021-9673
Subject:
partition coefficients,   etc   ; countercurrent chromatography; equations; recycling; solutes;     Show all 5 Subjects
Abstract:
... Closed-loop recycling dual-mode counter-current chromatography (CLR DM CCC) processes consist of two successive separation stages: separation of solutes in the recycling closed-loop with mobile x-phase and separation of solutes in the counter-current mode with mobile y-phase. Several variants of the implementation of this separation method can be developed: the closed-loop recycling stage may cons ...
DOI:
10.1016/j.chroma.2019.01.018

16. Bioaccumulation of short-chain chlorinated paraffins in chicken (Gallus domesticus): Comparison to fish

Author:
Sun, Runxia; Chen, Jiemin; Shao, Haiyang; Tang, Liang; Zheng, Xiaobo; Li, Qing X.; Wang, Yangyang; Luo, Xiaojun; Mai, Bixian
Source:
Journal of hazardous materials 2020 v.396 pp. 122590
ISSN:
0304-3894
Subject:
partition coefficients,   etc   ; adults; alkanes; bioaccumulation; chickens; dietary nutrient sources; fish; lipids; liver; models; muscles; pollutants; tissue distribution; topsoil;     Show all 14 Subjects
Abstract:
... Short chain chlorinated paraffins (SCCPs) are a complex group of chlorinated organic pollutants that have raised an increasing public attention. However, limited information is currently available on the bioaccumulation of SCCPs in terrestrial birds which are abundant and widely distributed around the world. In the present study, chicken (Gallus domesticus) was used as a model organism to provide ...
DOI:
10.1016/j.jhazmat.2020.122590

17. Does phase ratio in reversed phase high performance liquid chromatography vary with temperature?

Author:
Soare, Andreia-Cristina; David, Victor; Moldoveanu, Serban C.
Source:
Journal of chromatography 2020 v.1620 pp. 461023
ISSN:
0021-9673
Subject:
partition coefficients,   etc   ; acetonitrile; enthalpy; entropy; hydrocarbons; hydrophobicity; octanol; phase transition; reversed-phase high performance liquid chromatography; temperature;     Show all 10 Subjects
Abstract:
... Phase ratio Φ for an high performance liquid chromatography (HPLC) column is a parameter defined as the ratio between the volume of the stationary phase Vₛ and the void volume of the column Vₘ. Together with the equilibrium constant K of the separation process, phase ratio is part of the retention factor k (k = KΦ). Although a considerable number of studies have been dedicated to the evaluation of ...
DOI:
10.1016/j.chroma.2020.461023

18. Partitioning of polymers between bulk and porous media: Monte Carlo study of the effect of pore size distribution

Author:
Wang, Xiu; Procházka, Karel; Limpouchová, Zuzana
Source:
Journal of colloid and interface science 2020 v.567 pp. 103-112
ISSN:
0021-9797
Subject:
partition coefficients,   etc   ; Monte Carlo method; adsorption; entropy; gel chromatography; hydrodynamics; molecular weight; polymers; porosity; porous media; solvents;     Show all 11 Subjects
Abstract:
... In this paper we investigated the partitioning of polymer chains between bulk solvent and porous stationary phase under conditions appropriate for the chromatography under critical conditions (LCCC) close to the critical adsorption point (CAP). We addressed the concentration effect and the thermodynamic effect of pore-size dispersity (PSD) and their impacts on chromatography, i.e., the topics whic ...
DOI:
10.1016/j.jcis.2020.01.119

19. Occurrence and mass loads of biocides in plastic debris from the Pearl River system, South China

Author:
Jia, Yu-Wei; Huang, Zheng; Hu, Li-Xin; Liu, Shan; Li, Heng-Xiang; Li, Jin-Ling; Chen, Chang-Er; Xu, Xiang-Rong; Zhao, Jian-Liang; Ying, Guang-Guo
Source:
Chemosphere 2020 v.246 pp. 125771
ISSN:
0045-6535
Subject:
partition coefficients,   etc   ; biocides; branches; deet; leaves; methylparaben; microplastics; pollutants; rivers; surface water; trees; triclosan; water pollution; China;     Show all 14 Subjects
Abstract:
... Chemical pollution in the plastic debris is an increasing global concern as most pollutants might transfer from the environment to living organisms via plastic debris. In this study, biocides in the plastic debris floating on the surface water of the Pearl River system were investigated. The abundances of large plastic debris and microplastics in the surface water were 0.07 ± 0.13 and 0.94 ± 1.87 ...
DOI:
10.1016/j.chemosphere.2019.125771

20. A framework to model exposure to per- and polyfluoroalkyl substances in indoor environments

Author:
Eichler, Clara M. A.; Little, John C.
Source:
Environmental science 2020 v.22 no.3 pp. 500-511
ISSN:
2050-7895
Subject:
partition coefficients,   etc   ; coatings; dust; environmental health; exposure models; human health; per- and polyfluoroalkyl substances; products and commodities; volatile organic compounds;     Show all 9 Subjects
Abstract:
... Per- and polyfluoroalkyl substances (PFAS) include a wide range of halogenated chemicals, which have been used as water- and stain-resistant coatings for consumer products and industrial purposes. PFAS are persistent in the environment and several are bioaccumulative, and thus relevant for human and environmental health. Given their pervasiveness, we need to understand how we are exposed to PFAS, ...
DOI:
10.1039/c9em00556k