The effect of humic acid on the stability and aggregation kinetics of WO3 nanoparticles

The aggregation kinetics of C60 nanoparticles have been investigated over a wide range of monovalent and divalent electrolyte concentrations by employing time-resolved dynamic light scattering (DLS). The results showed that the presence of electrolyte made a dramatic decrease in the surface zeta potential and increase in the particle size. The aggregation kinetics of C60 nanoparticles exhibited reaction-limited and diffusion-limited regimes, which was found to be consistent with the classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal stability. The critical coagulation concentration (CCC) values of C60 nanoparticles were estimated as 321mM Na+, 295mM K+, 9.6mM Ca2+and 6.7mM Mg2+, which were far higher than the electrolyte concentrations in natural water. The enhanced C60 stability in the presence of humic acid was attributable to steric repulsion. Therefore C60 nanoparticles can be relatively stable in typical aquatic environments.

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Aggregation Kinetics of Humic Acid: Effects of Ca2+ Concentration

Functions of Natural Organic Matter in Changing Environment ◽

10.1007/978-94-007-5634-2_61 ◽

2012 ◽

pp. 335-339 ◽

Cited By ~ 2

Author(s):

N. S. Kloster ◽

M. Brigante ◽

G. Zanini ◽

M. J. Avena

Keyword(s):

Humic Acid ◽

Aggregation Kinetics ◽

Kinetics Of

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Influence of humic acid on the aggregation kinetics of fullerene (C60) nanoparticles in monovalent and divalent electrolyte solutions

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2007.01.074 ◽

2007 ◽

Vol 309 (1) ◽

pp. 126-134 ◽

Cited By ~ 459

Author(s):

Kai Loon Chen ◽

Menachem Elimelech

Keyword(s):

Humic Acid ◽

Electrolyte Solutions ◽

Fullerene C60 ◽

Aggregation Kinetics ◽

Kinetics Of

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Aggregation kinetics of fragmental PET nanoplastics in aqueous environment: Complex roles of electrolytes, pH and humic acid

Environmental Pollution ◽

10.1016/j.envpol.2020.115828 ◽

2021 ◽

Vol 268 ◽

pp. 115828

Author(s):

Shunan Dong ◽

Wangwei Cai ◽

Jihong Xia ◽

Liting Sheng ◽

Weimu Wang ◽

...

Keyword(s):

Humic Acid ◽

Aggregation Kinetics ◽

Aqueous Environment ◽

Kinetics Of

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Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

Nuklearmedizin ◽

10.1055/s-0037-1620623 ◽

1977 ◽

Vol 16 (04) ◽

pp. 157-162 ◽

Cited By ~ 1

Author(s):

C. Schümichen ◽

B. Mackenbrock ◽

G. Hoffmann

Keyword(s):

Normal Saline ◽

Half Life ◽

Compound A ◽

Short Half Life ◽

Low Concentrations ◽

The Stability ◽

Kinetics Of ◽

In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

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Functional Fractionation of Platelets: Aggregation Kinetics and Glycoprotein Labeling of Differing Platelet Populations

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657259 ◽

1982 ◽

Vol 48 (02) ◽

pp. 211-216 ◽

Cited By ~ 12

Author(s):

V M Haver ◽

A R L Gear

Keyword(s):

Galactose Oxidase ◽

Aggregation Kinetics ◽

Maximal Rate ◽

Membrane Glycoproteins ◽

Whole Cells ◽

Reversible Aggregation ◽

Significant Difference ◽

Small Doses ◽

Major Loss ◽

Kinetics Of

SummaryPlatelet heterogeneity has been studied with a technique called functional fractionation which employs gentle centrifugation to yield subpopulations (“reactive” and “less-reactive” platelets) after exposure to small doses of aggregating agent. Aggregation kinetics of the different platelet populations were investigated by quenched-flow aggregometry. The large, “reactive” platelets were more sensitive to ADP (Ka = 1.74 μM) than the smaller “less-reactive” platelets (Ka = 4.08 μM). However, their maximal rate of aggregation (Vmax, % of platelets aggregating per sec) of 23.3 was significantly lower than the “less-reactive” platelets (Vmax = 34.7). The “reactive” platelets had a 2.2 fold higher level of cyclic AMP.Platelet glycoproteins were labeled using the neuraminidase-galactose oxidase – [H3]-NaBH4 technique. When platelets were labeled after reversible aggregation, the “reactive” platelets showed a two-fold decrease in labeling efficiency (versus control platelets). However, examination of whole cells or membrane preparations from reversibly aggregated platelets revealed no significant difference in Coomassie or PAS (Schiff) staining.These results suggest that the large, “reactive” platelets are more sensitive to ADP but are not hyperaggregable in a kinetic sense. Reversible aggregation may cause a re-orientation of membrane glycoproteins that is apparently not characterized by a major loss of glycoprotein material.

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