Characterizing Manufactured Nanoparticles in the Environment: Multimethod Determination of Particle Sizes

2009 ◽  
Vol 43 (19) ◽  
pp. 7277-7284 ◽  
Author(s):  
Rute F. Domingos ◽  
Mohamed A. Baalousha ◽  
Yon Ju-Nam ◽  
M. Marcia Reid ◽  
Nathalie Tufenkji ◽  
...  
Keyword(s):  
Particle Sizes ◽  
Manufactured Nanoparticles

Effects of Particle Size and Method of Milling on Determination of Morphine in Papaver somniferum L. Straw

1982 ◽  
Vol 65 (3) ◽  
pp. 651-654
Author(s):  
Beatriz Ferreira Engelke ◽  
Phillip G Vincent
Keyword(s):  
Particle Size ◽  
High Pressure ◽  
Liquid Chromatography ◽  
High Pressure Liquid Chromatography ◽  
Reproducibility Of Results ◽  
Ball Mill ◽  
Papaver Somniferum ◽  
Particle Sizes ◽  
Morphine Content

Abstract Different particle sizes of blade- and ball-milled poppy straw were separated and analyzed for morphine by high pressure liquid chromatography. Morphine content varied up to 70% among the different size particles. This may account for discrepancies observed in percentages of morphine found among random aliquots. Homogenizing a carefully quartered sample of blade-milled straw by further pulverization in a percussion ball mill 2 min and taking a quartered aliquot for morphine analysis improved the reproducibility of results.

Modified Procedure for Determining Mercury in Coal by Cold Vapor Atomic Absorption Spectrophotometry

1973 ◽  
Vol 56 (6) ◽  
pp. 1509-1510
Author(s):  
Fa-Chun Lo ◽  
Brian Bush
Keyword(s):  
Atomic Absorption ◽  
Atomic Absorption Spectrophotometry ◽  
Particle Sizes ◽  
Cold Vapor ◽  
Absorption Spectrophotometry ◽  
Cold Vapor Atomic Absorption

Abstract The combustion procedure previously described for the determination of mercury in coal by cold vapor atomic absorption spectrophotometry has been modified to permit samples to be analyzed more rapidly and with better precision. A coefficient of 8.3% was obtained for the analysis of 7 samples containing 0.1 ppm mercury. In addition a greater variety of types and particle sizes of coal can be analyzed by the modified procedure.

scholarly journals Hairy Fluorescent Nanospheres Based on Polyelectrolyte Brush for Highly Sensitive Determination of Cu(II)

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 577 ◽  
Author(s):  
Qiaoling Wang ◽  
Kaimin Chen ◽  
Yi Qu ◽  
Kai Li ◽  
Ying Zhang ◽  
...  
Keyword(s):  
Metal Ions ◽  
Coupling Method ◽  
Carboxyl Groups ◽  
Particle Sizes ◽  
Carboxyl Content ◽  
High Brightness ◽  
Highly Sensitive ◽  
Sensitive Determination ◽  
Content Range

Currently, it is an ongoing challenge to develop fluorescent nanosphere detectors that are uniform, non-toxic, stable and bearing a large number of functional groups on the surface for further applications in a variety of fields. Here, we have synthesized hairy nanospheres (HNs) with different particle sizes and a content range of carboxyl groups from 4 mmol/g to 9 mmol/g. Based on this, hairy fluorescent nanospheres (HFNs) were prepared by the traditional coupling method (TCM) or adsorption-induced coupling method (ACM). By comparison, it was found that high brightness HFNs are fabricated based on HNs with poly (acrylic acid) brushes on the surface via ACM. The fluorescence intensity of hairy fluorescent nanospheres could be controlled by tuning the content of 5-aminofluorescein (5-AF) or the carboxyl groups of HNs easily. The carboxyl content of the HFNs could be as high as 8 mmol/g for further applications. The obtained HFNs are used for the detection of heavy metal ions in environmental pollution. Among various other metal ions, the response to Cu (II) is more obvious. We demonstrated that HFNs can serve as a selective probe and for the separation and determination of Cu(II) ions with a linear range of 0–0.5 μM and a low detection limit of 64 nM.

Dynamic Light Scattering at CdSe Nanocrystals and CdSe Cluster-Molecules

2000 ◽  
Vol 636 ◽  
Author(s):  
A. Eichhöfer ◽  
C.V. Hänisch ◽  
M. Jacobsohn ◽  
U. Banin
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
High Performance ◽  
Size Range ◽  
Blue Shift ◽  
Cdse Nanocrystals ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
X Ray

AbstractHigh performance dynamic light scattering (DLS) has been used to determine the hydrodynamic diameters of CdSe-nanocrystals as well as CdSe cluster molecules in a size range of 1 to 10 nm. The method enables the determination of the particle sizes including the ligand shells directly in solution. Consistent with the blue shift of the absorption onset by reducing the particle sizes the values for the hydrodynamic radii decrease. For the CdSe nanoparticles the measured sizes were compared with the diameters determined by TEM experiments; the sizes of the cluster molecules were on the other hand estimated from the space filling models of the single crystal X-ray structure determination. Regarding both types of compounds, DLS yield comparable values for the radii, indicating that it provides a potentially important tool in addition to other size determining techniques like TEM, which operates at more drastic conditions, and powder X-ray diffraction being difficult to interpret below 5 nm.

Sign in / Sign up

Export Citation Format

Share Document