Colloidal molybdoantimonic acids as ion exchangers

1991 ◽  
Vol 69 (2) ◽  
pp. 293-299 ◽  
Author(s):  
M. Koné ◽  
P. Courtin ◽  
J. Lemerle
Keyword(s):  
Colloidal Particles ◽  
Polymerization Process ◽  
Exchange Reactions ◽  
Aqueous Dispersions ◽  
Normal Distributions ◽  
Mean Size ◽  
The Mean ◽  
Mo Content ◽  
The Stability ◽  
Log Normal

Colloidal particles with a c.c.p. structure were obtained from mixtures of antimonic and molybdic acids through a polymerization process. These particles were octahedral and their sizes fits the log-normal distributions. The mean size decreases and the polydispersity increases with increasing Mo content in the particles. The stability of the aqueous dispersions was due to the surface charge density of the particles which was enhanced when increasing the Mo content. Ion exchange reactions can occur with the dispersions. Two different routes lead to Ag+ fixation: substitution of core H+ without flocculation of the dispersion or cancellation of external charges with flocculation. Key words: inorganic exchangers, colloids, antimonic acid, molybdic acid.

586. Colour changes in heated and unheated milk: IV. the theoretical background to the reflectance changes in separated milk

1955 ◽  
Vol 22 (2) ◽  
pp. 200-204 ◽  
Author(s):  
H. Burton
Keyword(s):  
Soluble Protein ◽  
Colloidal Particles ◽  
Theoretical Background ◽  
General Level ◽  
Colloidal Solutions ◽  
Casein Micelles ◽  
Scattering Of Light ◽  
Colour Changes ◽  
Mean Size ◽  
The Mean

The theory of the scattering of light in colloidal solutions is considered. As a result it is suggested that the reflectance changes in milk which involve a rise or fall in the general level of reflectance are caused by an increase or decrease in the mean size of the colloidal particles. Whether the particles responsible are the casein micelles or the soluble protein depends on the phenomenon to be explained.The change in reflectance on the browning of milk, which is dependent on wavelength, is considered to have a more complex cause, involving the production of absorbing molecules.

scholarly journals On the stability of aqueous dispersions containing conducting colloidal particles

Soft Matter ◽  
2015 ◽  
Vol 11 (20) ◽  
pp. 4011-4021 ◽  
Author(s):  
Ryan Szparaga ◽  
Clifford E. Woodward ◽  
Jan Forsman
Keyword(s):  
Electrolyte Solution ◽  
Theoretical Approach ◽  
Colloidal Particles ◽  
Aqueous Dispersions ◽  
The Stability

We use a combination of simulations and a simple theoretical approach to investigate interactions between neutral conducting surfaces, immersed in an electrolyte solution.

Framboid Sizes

2021 ◽  
pp. 21-46
Author(s):  
David Rickard
Keyword(s):  
Water Column ◽  
Marine Sediments ◽  
Geometric Mean ◽  
Atomic Clusters ◽  
Normal Distributions ◽  
Nanoparticle Clusters ◽  
Mean Diameter ◽  
The Mean ◽  
Framboid Formation ◽  
Log Normal

Framboid size-frequency plots show log-normal distributions with a geometric mean diameter of 6.0 μ‎m and with 95% of framboids ranging between 2.9 and 12.3 μ‎m. The largest framboids may be 250 μ‎m in diameter, although spherical aggregates of framboids, known as polyframboids, may range up to 900 μ‎m in diameter. Various spherical clusters of nanoparticles have been described which are less than 0.2 μ‎m in diameter. These do not form a continuum with framboids. There is no evidence for any significant change in framboid diameters with geologic time, and the differences in mean sizes between hydrothermal and sedimentary framboids do not, at present, appear to be statistically significant. By contrast, it appears that the mean diameters of framboids from non-marine sediments are significantly larger (7.6 μ‎m) than marine framboids (5.7 μ‎m). There is some evidence that framboids formed in the water column are smaller than those formed in sediments, but the non-critical use of this possible difference as a proxy for paleoenvironmental reconstructions is not robust. So-called microframboids and nanoframboids are discrete entities which are distinct from framboids. They are nanoparticle clusters and are not produced by the same processes as those involved in framboid formation, nor do they behave in the same way. They are more akin to atomic clusters, which form similar constructs.

Uncertainty of Design Parameters From Viewpoint of Extreme Statistics

1992 ◽  
Vol 114 (2) ◽  
pp. 76-82 ◽  
Author(s):  
Y. Goda
Keyword(s):  
Distribution Function ◽  
Standard Deviation ◽  
Sample Size ◽  
Design Parameters ◽  
Empirical Formulas ◽  
Extreme Statistics ◽  
Normal Distributions ◽  
The Mean ◽  
Log Normal ◽  
Return Value

Statistical variability of a sample of extreme data has been examined by means of Monte Carlo simulations. The Fisher-Tippett types I and II, the Weibull, and the log-normal distributions were chosen for the examination. The sample size covered from 10 to 400, and 10,000 runs were carried out for each combination of sample size, censoring rate, and distribution function. Empirical formulas and tables are presented for the mean and the coefficient of variation of the standard deviation of a sample, the standard deviation of return value, and the confidence interval of return period.

The Stability Study of Nifeviroc-Loaded Microemulsions

2012 ◽  
Vol 528 ◽  
pp. 277-280
Author(s):  
Hong Jing Zhou ◽  
Fang Tian ◽  
Qiang Xia ◽  
Li Chen ◽  
Wei Hua Li ◽  
...  
Keyword(s):  
High Speed ◽  
Storage Stability ◽  
Retention Rate ◽  
Stability Study ◽  
Size Analysis ◽  
Loading Capacity ◽  
Before And After ◽  
Mean Size ◽  
The Mean ◽  
The Stability

The objective is to study the stability of Nifeviroc-loaded microemulsions (Nifeviroc-MEs). The dilution stability of Nifeviroc-MEs with different loading capacity ( 0.1%, 0.2%, 0.3%) was tested by change of mean size, pH and appearance. The centrifugal stability was evaluated by comparing the mean size of Nifeviroc-MEs and dilutions before and after high-speed centrifugation for 30, 60, 120 min at 10000 rpm. The storage stability was evaluated by the change of appearance, the mean size, PDI and the retention rate of Nifeviroc in the ME. The pH, appearance, size analysis and retention rate results showed the Nifeviroc-MEs had good dilution, centrifugal stability and good storage stability without light.

Injuries to the Coronoid Process of the Ulna with Involvement of the Lesser Sigmoid Notch

2020 ◽  
Author(s):  
Valentin Rausch ◽  
Sina Neugebauer ◽  
Tim Leschinger ◽  
Lars Müller ◽  
Kilian Wegmann ◽  
...  
Keyword(s):  
Fragment Size ◽  
Coronoid Process ◽  
Annular Ligament ◽  
Concomitant Injuries ◽  
Proximal Ulna ◽  
Sigmoid Notch ◽  
Coronoid Fractures ◽  
The Mean ◽  
The Stability ◽  
Arthritic Changes

Abstract Introduction This study aimed to describe the involvement of the lesser sigmoid notch in fractures to the coronoid process. We hypothesized that injuries to the lateral aspect of the coronoid process regularly involve the annular ligament insertion at the anterior lesser sigmoid notch. Material and Methods Patients treated for a coronoid process fracture at our institution between 06/2011 and 07/2018 were included. We excluded patients < 18 years, patients with arthritic changes or previous operative treatment to the elbow, and patients with concomitant injuries to the proximal ulna. In patients with involvement of the lesser sigmoid notch, the coronoid height and fragment size (anteroposterior, mediolateral, and craniocaudal) were measured. Results Seventy-two patients (mean age: 47 years ± 17.6) could be included in the study. Twenty-one patients (29.2%) had a fracture involving the lateral sigmoid notch. The mean anteroposterior fragment length was 7 ± 1.6 mm. The fragment affected a mean of 43 ± 10.8% of the coronoid height. The mean mediolateral size of the fragment was 10 ± 5.0 mm, and the mean cranio-caudal size was 7 ± 2.7 mm. Conclusion Coronoid fractures regularly include the lesser sigmoid notch. These injuries possibly affect the anterior annular ligament insertion which is important for the stability of the proximal radioulnar joint and varus stability of the elbow.

Instant 99mTc-Labelled Glucoheptonate Kit for Kidney Imaging

1983 ◽  
Vol 22 (05) ◽  
pp. 246-250 ◽  
Author(s):  
M. Al-Hilli ◽  
H. M. A. Karim ◽  
M. H. S. Al-Hissoni ◽  
M. N. Jassim ◽  
N. H. Agha
Keyword(s):  
Sodium Hydroxide Solution ◽  
Normal Subjects ◽  
Organ Distribution ◽  
Stable Complex ◽  
Scintillation Camera ◽  
Ph Adjustment ◽  
The Mean ◽  
The Stability ◽  
Kidney Imaging ◽  
Mean Concentration

Gelchromatography column scanning has been used to study the fractions of reduced hydrolyzed 99mTc, 99mTc-pertechnetate and 99mTc-chelate in a 99mTc-glucoheptonate (GH) preparation. A stable high labelling yield of 99mTc-GH complex in the radiopharmaceutical has been obtained with a concentration of 40-50 mg of glucoheptonic acid-calcium salt and not less than 0.45 mg of SnCl2 2 H2O at an optimal pH between 6.5 and 7.0. The stability of the complex has been found significantly affected when sodium hydroxide solution was used for the pH adjustment. However, an alternative procedure for final pH adjustment of the preparation has been investigated providing a stable complex for the usual period of time prior to the injection. The organ distribution and the blood clearance data of 99mTc-GH in rabbits were relatively similar to those reported earlier. The mean concentration of the radiopharmaceutical in both kidneys has been studied in normal subjects for one hour with a scintillation camera and the results were satisfactory.

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