Hydration and Ion Pairing in Aqueous Sodium Oxalate Solutions

ChemPhysChem ◽  
2003 ◽  
Vol 4 (4) ◽  
pp. 373-378 ◽  
Author(s):  
Richard Buchner ◽  
Faradj Samani ◽  
Peter M. May ◽  
Peter Sturm ◽  
Glenn Hefter
Keyword(s):  
Ion Pairing ◽  
Sodium Oxalate ◽  
Aqueous Sodium

EUROPIUM OXALATE ION ASSOCIATION IN WATER

1966 ◽  
Vol 44 (24) ◽  
pp. 3057-3062 ◽  
Author(s):  
P. G. Manning
Keyword(s):  
Acetic Acid ◽  
Ionic Strength ◽  
Stability Constant ◽  
Stability Constants ◽  
Aqueous Phase ◽  
Sodium Acetate ◽  
Ion Association ◽  
Sodium Oxalate ◽  
Aqueous Sodium ◽  
Oxalate Ion

The partitioning of radiotracer 152/151Eu between aqueous sodium oxalate (Na2L) solutions and toluene solutions of thenoyltrifluoroacetone (HTTA) has been studied as a function of the oxalate concentration. The pH of the aqueous phase was controlled by means of sodium acetate – acetic acid mixtures and the ionic strength (I) by NaCl or NaClO4.At low ionic strengths (~0.05) and [L] ~10−4 M EuL+ formed, but at I = 0.95 and [L] ~10−3 M EuL2− also formed. Stability constants for the 1:1 and 1:2 (metal:ligand) complexes are reported.The magnitudes of the stepwise stability constant ratios are discussed.

scholarly journals Anodisation of Aluminium in Aqueous Sodium Oxalate and Sodium Sulphate Media

2013 ◽  
Vol 38 ◽  
pp. 9-16
Author(s):  
CM Mustafa ◽  
MA Habib ◽  
MS Islam
Keyword(s):  
Reference Electrode ◽  
Visual Observation ◽  
Sodium Sulphate ◽  
Sodium Oxalate ◽  
Aqueous Sodium ◽  
Surface Breakdown ◽  
Constant Potential ◽  
Sulphate Media ◽  
Concentration Graphs ◽  
Current Potential

An investigation was conducted on the anodisation of commercial grade aluminium in aqueous sodium sulphate and sodium oxalate solutions. The parameters investigated were anodisation potential and electrolyte composition. Degree of anodisation was evaluated by visual observation of the anodised surface, analyses of current-concentration graphs at constant potential and current-potential characteristics, and measurement of corrosion rate of the anodised surface. Anodisation potential played an important role on the degree of anodisation. The optimum potential was 400 mV and 800 mV wrt saturated Ag/AgCl (SSE) reference electrode for sodium sulphate and sodium oxalate solutions respectively. Below and above the optimum potential poor anodisation was due to insufficient production of Al3+ to form anodic film and surface breakdown respectively. Anodisation increased with the increase of oxalate concentration. Sulphate concentration was less effective on the degree of anodisation. Between the two electrolytes sodium oxalate was more suitable than sodium sulphate for aluminium anodisation. DOI: http://dx.doi.org/10.3329/rujs.v38i0.16544 Rajshahi University J. of Sci. 38, 09-16 (2010)

scholarly journals Strong enrichment of atmospherically relevant organic ions at the aqueous interface: the role of ion pairing and cooperative effects

2018 ◽  
Vol 20 (42) ◽  
pp. 27185-27191 ◽  
Author(s):  
Victor Ekholm ◽  
Carl Caleman ◽  
Nicklas Bjärnhall Prytz ◽  
Marie-Madeleine Walz ◽  
Josephina Werner ◽  
...  
Keyword(s):  
Ion Pairing ◽  
Aqueous Sodium ◽  
Cooperative Effects ◽  
Organic Ions ◽  
Atmospherically Relevant

Surface affinity, orientation and ion pairing are investigated in mixed and single solute systems of aqueous sodium hexanoate and hexylammonium chloride.

scholarly journals RECOVERY OF METALS FROM ELECTROACTIVE COMPONENTS OF SPENT Ni-MH BATTERIES AFTER LEACHING WITH FORMIC ACID

Detritus ◽  
2021 ◽  
pp. 68-77
Author(s):  
Pedro Rosário Gismonti ◽  
Jéssica Frontino Paulino ◽  
Julio Afonso
Keyword(s):  
Aqueous Solution ◽  
Formic Acid ◽  
Sodium Formate ◽  
Sodium Oxalate ◽  
Slow Evaporation ◽  
Nickel Metal ◽  
Nickel Metal Hydride ◽  
Aqueous Sodium ◽  
Nickel Cobalt ◽  
Cobalt Iron

this work describes a route for recovering nickel, cobalt, iron, zinc and lanthanides from spent nickel-metal hydride batteries. Formic acid was used as leachant. Experiments were run at 25-50°C for 1-4 h. Under the best conditions leaching yields surpassed 99 wt.%, except for iron. The insoluble matter contains almost solely iron as iron(III) basic formate. The leachate went through six separation procedures, combining solvent extraction with D2EHPA as extractant, and precipitation reactions. Fe2+ and Zn2+ were extracted together (> 99 wt.%) from the original leachate (pH ~1.5). Yttrium and lanthanides were precipitated as oxalates directly from the raffinate (> 99.9 wt.%) upon addition of sodium oxalate. In the next steps, Mn2+ and Co2+ were extracted with D2EHPA at buffered pH (3 and ~4.8, respectively), after adding NaOHaq. About 10 wt.% of leached Ni2+ was coextracted with Co2+. The remaining Ni2+ was precipitated from the raffinate after addition of aqueous sodium oxalate at pH 6. After precipitation of Al3+ upon addition of NaOHaq. until pH ~8, sodium formate was recovered after slow evaporation of the final aqueous solution at 60oC. It contains ~90 wt.% of the formate present in the leachant.

Changes Occurring During Coagulation in Glass. I. Normal Human Blood

1960 ◽  
Vol 4 (01) ◽  
pp. 001-016
Author(s):  
Jessica H. Lewis ◽  
Paul Didisheim ◽  
John H. Ferguson ◽  
Kenichi Hattori
Keyword(s):  
Coagulation Factors ◽  
Factor Ix ◽  
Factor Vii ◽  
Sodium Oxalate ◽  
Factor V ◽  
Rapid Rise ◽  
Rapid Fall ◽  
Glass Tubes ◽  
Normal Human ◽  
The Individual

SummaryNormal whole blood was allowed to stand in glass tubes at 37° C, and the clotting process stopped at various intervals by the addition of sodium oxalate. During the first 15 minutes a marked acceleration of clotting activity was found. Study of the individual coagulation factors showed the following changes: a sustained and rapid fall in platelet count, a sustained and rapid rise in PTC (factor IX), a steady fall in fibrinogen, a more gradual fall in AHF (factor VIII), a rapid rise and subsequent fall in proaccelerin (factor V) activity, a somewhat lesser and slower rise and fall in proconvertin (factor VII) activity, and a slow fall in prothrombin concentration. No changes were noted in Hageman factor or PTA activities.

Экологическая и сортовая изменчивость морфометрических параметров семян моркови

2019 ◽  
Author(s):  
A.F. Bukharov ◽  
D.N. Baleev ◽  
E.V. Kashnova ◽  
G.V. Kasaeva ◽  
M.I. Ivanova ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Morphometric Parameters ◽  
Sodium Hypochlorite Solution ◽  
The West ◽  
Seed Length ◽  
Hypochlorite Solution ◽  
Aqueous Sodium ◽  
Altai Region ◽  
Experimental Station ◽  
Embryo Length

Цель исследований: изучение влияния сортового и экологического факторов на изменчивость морфометрических (длина семени, эндосперма и зародыша) параметров семян моркови в системе двухфакторного опыта. Объекты для изучения – оригинальные семена сортов Шантенэ 2461 и Боярыня. Опыты были заложены в 2015–2017 годах на Западно-Сибирской овощной опытной станции ФГБНУ ВНИИО в южной части Первомайского района Алтайского края. Преобладающие почвы – черноземы выщелоченные и обыкновенные. Повторность опыта трехкратная, в каждой повторности не менее 20 семян. Измерение длины семени и эндосперма проводили штангенциркулем (ГОСТ 166-89), длину зародыша определяли с использованием микроскопа Микромед и видеоокуляра DCM 300 MD. Семена замачивали в 14%-ном водном растворе гипохлорита натрия в течение 1 ч, после чего измеряли длину семени, эндосперма и зародыша и рассчитывали соотношение длины зародыша (E) к длине эндосперма (S). Семена двух сортов моркови, за годы исследования существенно различались по длине семян (Р < 0,001). Длина эндосперма сорта Боярыня в среднем за годы исследований была меньше (Р < 0,001) по сравнению с Шантенэ 2461. Длина зародыша также существенно отличалась (Р < 0,001) в зависимости от сорта. Экологический фактор значительно влиял на длину семени (Р=0,005) и эндосперма (Р=0,003). На длину зародыша основное влияние оказывал фактор сорта (Р < 0,001). На отношение длины зародыша к длине эндосперма также в значительной степени влиял фактор сорта (Р = 0,006). Исследования показали, что изменчивость морфометрических параметров семян обусловлена как влиянием сорта, так и влиянием условий года репродукции. Длина зародыша по сравнению с другими элементами семени варьирует сильнее и в большей степени зависит от влияния наследственного фактора. Это позволяет сделать вывод о возможности селекционного изменения линейных, а также относительных размеров морфологических элементов семени.The article is devoted to the study of the effect of varietal and environmental factors on the variability of morphometric (seed length, endosperm and germ) parameters of carrot seeds. The objects for the study were the original seeds of different varieties grown in 2015, 2016 and 2017. Seeds obtained from two varieties of carrots over the years of research differed significantly in the length of the seeds (P <0.001). The length of the endosperm varieties Boyarynya on average over the years of research was less (P <0.001) compared with Shantane 2461. The experiments were conducted in 2015-2017 at the West Siberian Vegetable Experimental Station in the southern part of the Pervomaisky district of the Altai region. The prevailing soils are leached and ordinary chernozems. Experiment replication is 3, each repeatability consists at least 20 seeds. The measurement of the length of the seed and the endosperm was carried out with Vernier caliper (GOST 166-89), the length of the embryo was determined using microscope Mikromed and video-ocular DCM 300 MD. Seeds were soaked in 14% aqueous sodium hypochlorite solution for 1 h, and then measured the length of the seed, the endosperm and the embryo, and calculated the ratio of the length of the embryo (E) to the length of the endosperm (S). Embryo length was also significantly different (P <0.001) depending on the variety. The environmental factor had a significant impact on the length of the seed (P = 0.005) and endosperm (P = 0.003). The length of the embryo was mainly affected by the factor of the variety (P <0.001). The ratio of the embryo length to the endosperm length was largely influenced by the factor of the variety (P = 0.006). Our studies have shown that the variability of the morphometric parameters of seeds is due to both the influence of the variety and the conditions of the year of reproduction. In comparison with other elements of the seed, the embryo length varies more and depends more on the influence of the hereditary factor. This allows us to conclude about the possibility of a selection change in linear as well as relative sizes of the morphological elements of the seed.

Ion Pairing and Dielectric Decrement in Glycosaminoglycan Brushes

2020 ◽  
Author(s):  
James Sterling ◽  
Wenjuan Jiang ◽  
Wesley M. Botello-Smith ◽  
Yun L. Luo
Keyword(s):  
Molecular Dynamics ◽  
Ion Pairs ◽  
Mean Field ◽  
Salt Bridge ◽  
Ion Pairing ◽  
Donnan Potential ◽  
Mean Field Models ◽  
Ion Exclusion ◽  
Dynamics Simulations ◽  
Contact Ion Pairs

Molecular dynamics simulations of hyaluronic acid and heparin brushes are presented that show important effects of ion-pairing, water dielectric decrease, and co-ion exclusion. Results show equilibria with electroneutrality attained through screening and pairing of brush anionic charges by cations. Most surprising is the reversal of the Donnan potential that would be expected based on electrostatic Boltzmann partitioning alone. Water dielectric decrement within the brush domain is also associated with Born hydration-driven cation exclusion from the brush. We observe that the primary partition energy attracting cations to attain brush electroneutrality is the ion-pairing or salt-bridge energy associated with cation-sulfate and cation-carboxylate solvent-separated and contact ion pairs. Potassium and sodium pairing to glycosaminoglycan carboxylates and sulfates consistently show similar abundance of contact-pairing and solvent-separated pairing. In these crowded macromolecular brushes, ion-pairing, Born-hydration, and electrostatic potential energies all contribute to attain electroneutrality and should therefore contribute in mean-field models to accurately represent brush electrostatics.

Sign in / Sign up

Export Citation Format

Share Document