Assessment of the uncertainty of trace metal and nitrogen concentrations in mosses due to sampling, sample preparation and chemical analysis based on the French contribution to ICP-Vegetation

The partitioning of Zn, Mn, Cd and Se within mesozooplankton, mainly calanoid copepods, is reported for two geographically close but biogeochemically distinct water masses (subtropical (ST) and subantarctic (SA) waters) during a transect east of New Zealand in austral spring 1997. Particular attention was paid to avoiding sample contamination during collection, handling and chemical analysis by using trace metal clean techniques. Mesozooplankton underwent a sequential chemical leaching scheme to determine the degree and type of elemental associations within labile and refractory tissues. All four elements showed a positive correlation with the phosphorus content of each fraction indicating a consistent relationship to the amount of tissue dissolved in each fraction. Ratios of Cd : P and Zn : P in samples from SA waters were over twice those in ST waters. However, no significant differences were found between Mn : P and Se : P ratios for samples from the two water masses.

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Levitated Drop Microreactors for Biochemical Kinetics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.560-561.395 ◽

2012 ◽

Vol 560-561 ◽

pp. 395-400

Author(s):

Alexander Scheeline ◽

Woo Hyuck Choi ◽

Edward T. Chainani ◽

Khan T. Ngo

Keyword(s):

Free Radicals ◽

Chemical Analysis ◽

Sample Preparation ◽

Chemical Processes ◽

Materials Processing ◽

Biochemical Reactions ◽

Biochemical Kinetics ◽

Catalyzed Reactions ◽

Enzyme Catalyzed Reactions ◽

Kinetics Of

Ultrasonically-levitated drops have been widely studied for materials processing and for sample preparation for chemical analysis. We report on the development of such drops for study of kinetics of enzyme-catalyzed reactions and other chemical processes. We review how to simply and reliably levitate drops, discuss why such drops are desirable for studying biochemical reactions, especially those generating or consuming free radicals, and report progress towards routine kinetics measurements in microliter drops.

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Sample preparation for the chemical analysis of debris in suspect arson cases

Analytica Chimica Acta ◽

10.1016/s0003-2670(00)83312-7 ◽

1990 ◽

Vol 236 ◽

pp. 183-195 ◽

Cited By ~ 27

Author(s):

W. Bertsch ◽

Qi-Wei Zhang

Keyword(s):

Chemical Analysis ◽

Sample Preparation

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Modern Sample Preparation Methods in Chemical Analysis

Microchimica Acta ◽

10.1007/s006040170054 ◽

2001 ◽

Vol 136 (3-4) ◽

pp. 199-204 ◽

Cited By ~ 17

Author(s):

Georgis Theodoridis ◽

I. N. Papadoyannis

Keyword(s):

Chemical Analysis ◽

Sample Preparation ◽

Preparation Methods ◽

Modern Sample ◽

Sample Preparation Methods

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Forensic Uses of Deflection (Y) Modulation and X-Ray Dot Mapping

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100119387 ◽

1985 ◽

Vol 43 ◽

pp. 512-513

Author(s):

S. Basu

Keyword(s):

Signal Processing ◽

Electron Microscope ◽

Chemical Analysis ◽

Scanning Electron Microscope ◽

Sample Preparation ◽

Secondary Electron ◽

Energy Dispersive ◽

X Ray ◽

Image Forensic ◽

Scanning Electron

The imaging capabilities of the scanning electron microscope in conjunction with an energy dispersive x-ray spectrometer (SEM-EDX) allow both topographical and compositional displays that can be readily interpreted. Illustrative evidence of this type would be valuable in forensic determinations, since the associated techniques of image formation, chemical analysis and sample preparation are well understood and documented. Various methods of signal processing are also available, which allow intuitive, stylistic and synthetic interpretation of the image. Forensic applications of two such methods will be stressed in this report using a AMR 1000 SEM. These are deflection modulation (DM) or “Y-modulation” of secondary electron signal^ and x-ray dot mapping.

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