Transference Numbers of Alkali Chlorides and Characterization of Salt Bridges for Use in Methanol + Water Mixed Solvents

Chemical and structural similarities between poorly preserved charcoal and its contaminants, as well as low radiocarbon concentrations in old samples, complicate 14C age determinations. Here, we characterize 4 fossil charcoal samples from the late Middle Paleolithic and early Upper Paleolithic strata of Kebara Cave, Israel, with respect to the structural and chemical changes that occur when they are subjected to the acid-base-acid (ABA) treatment. Differential thermal analysis and TEM show that acid treatment disrupts the structure, whereas alkali treatment results in the reformation of molecular aggregates. The major changes are ascribed to the formation of salt bridges at high pH and the disruption of the graphite-like crystallites at low pH. Weight losses during the treatments are consistently greater for older samples, implying that they are less well preserved. Based on the changes observed in vitro due to pH fluctuations, various methods for removing contamination, as well as a mechanism for preferential preservation of charcoal in nature, are proposed.

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Determination of Primary and Secondary Standards for pH Measurements inN-Methylacetamide and Its 0.50 Mass Fraction in Admixture with Water, with Characterization of Appropriate Salt Bridges

Journal of Chemical & Engineering Data ◽

10.1021/je600581j ◽

2007 ◽

Vol 52 (5) ◽

pp. 1595-1602 ◽

Cited By ~ 3

Author(s):

Doru Dumitrel ◽

Luigi Falciola ◽

Manuela Liotto ◽

Patrizia R. Mussini ◽

Torquato Mussini ◽

...

Keyword(s):

Mass Fraction ◽

Salt Bridges ◽

Ph Measurements ◽

Primary And Secondary Standards

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Synthesis and Characterization of Luminescent Rod-Coil Poly[2,7-(9,9- Dihexylfluorene)] - Block-Poly(2-(Dimethylamino) Ethyl Methacrylate) by Atom Transfer Radical Polymerization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.642 ◽

2008 ◽

Vol 47-50 ◽

pp. 642-645

Author(s):

Yang Yen Yu ◽

Wen Chen Chien ◽

Chia Liang Tsai

Keyword(s):

Atom Transfer Radical Polymerization ◽

Radical Polymerization ◽

Photophysical Properties ◽

Mixed Solvents ◽

Solvent System ◽

Synthesis And Characterization ◽

Photoluminescence Properties ◽

Ethyl Methacrylate ◽

Large Compound

The synthesis, morphology, and photophysical properties of Poly[2,7-(9,9-dihexyl fluorene)]- block-poly(2-(Dimethylamino) ethyl methacrylate) (PF-b-PDMAEMA) copolymers in various mixed solvents, i.e., THF/MeOH, DMF/MeOH, and 1,4-Dioxane/MeOH, with methanol contents of 0, 10, 25, 50, 75, 90 vol.% were reported. TEM images showed that different aggregate morphologies of PF-b-PDMAEMA, including spherical and large compound micelles, cylinder, nanorods, long stick-like structure, could be prepared by introducing different amount of methanol into the copolymer/solvent system. The results indicated that aggregate morphologies of PF-b-PDMAEMA, which obtained from various coil lengths and mixed solvents, had a great influenced on the optical and photoluminescence properties of the prepared PF-b-PDMAEMA copolymers.

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Solvothermal synthesis and characterization of LaPO4 with hierarchical nanostructure in mixed solvents of ethanol and water

Materials Letters ◽

10.1016/j.matlet.2014.03.092 ◽

2014 ◽

Vol 124 ◽

pp. 173-176 ◽

Cited By ~ 8

Author(s):

Ming-Guo Ma ◽

Fu Deng ◽

Ke Yao

Keyword(s):

Solvothermal Synthesis ◽

Mixed Solvents ◽

Synthesis And Characterization ◽

Hierarchical Nanostructure

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Preparation and characterization of PVDF/TiO2composite ultrafiltration membranes using mixed solvents

Membrane Water Treatment ◽

10.12989/mwt.2016.7.5.377 ◽

2016 ◽

Vol 7 (5) ◽

pp. 377-401 ◽

Cited By ~ 1

Author(s):

Maryam Tavakolmoghadam ◽

Toraj Mohammadi ◽

Mahmood Hemmati

Keyword(s):

Mixed Solvents ◽

Ultrafiltration Membranes

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The solvothermal synthesis and characterization of quaternary arsenic chalcogenides CsTMAsQ3 (TM = Hg, Cd; Q = S, Se) using Cs+ as a structure directing agent: from 1D anionic chains to 2D anionic layers

RSC Advances ◽

10.1039/d0ra05058j ◽

2020 ◽

Vol 10 (57) ◽

pp. 34903-34909

Author(s):

Xin-Yu Tian ◽

Cui-Xia Du ◽

GeTu ZhaoRi ◽

MuGe SheLe ◽

Yongsheng Bao ◽

...

Keyword(s):

Solvothermal Synthesis ◽

Mixed Solvents ◽

Synthesis And Characterization ◽

Structure Directing Agent

Presented is a method involving TM–As–Q (TM = Hg, Cd; Q = S, Se) quaternary arsenic chalcogenides and different mixed solvents which has been used to synthesize four new quaternary chalcogenide compounds.

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