Search results for "Blood Stains"
showing 3 items of 13 documents
Bleach interference in forensic luminol tests on porous surfaces: more about the drying time effect.
2009
As criminals try to avoid leaving clues at the scene of a crime, bloodstains are often washed away, but fortunately for investigators, they are difficult to eliminate completely. Porous surfaces easily retain blood traces, which are sometimes invisible to the naked eye. The reagent of choice for detecting latent blood traces on all types of surfaces is luminol, but its main disadvantage is a high degree of sensitivity to oxidising contaminants in the blood sample. If household bleach is used to clean bloodstains, presumptive tests are invalidated. Hypochlorites, however, are known to be unstable and deteriorate over time, and this feature could be of help in preventing household bleach-indu…
�ber die Eignung spektralanalytischer Methoden zur Bestimmung des Blutfleckenalters
1977
The spectrophotometric methods of Kind et al. and Kleihauer et al. were checked by more than 900 experiments on 85 blood stains on different material (cotton, nyltest and paper) from native and citrate blood, aged at room temperature up to 5 years. As a result, the variation of values within one age-group exceeded the differences between the values of samples of different age. Therefore, both methods are thought to be unsuitable for the estimation of blood stain age in practical forensic medicine, although the general trend described by the above authors could be confirmed.
The challenges of analysing blood stains with hyperspectral imaging
2014
Hyperspectral imaging is a potential noninvasive technology for detecting, separating and identifying various substances. In the forensic and military medicine and other CBRNE related use it could be a potential method for analyzing blood and for scanning other human based fluids. For example, it would be valuable to easily detect whether some traces of blood are from one or more persons or if there are some irrelevant substances or anomalies in the blood. This article represents an experiment of separating four persons' blood stains on a white cotton fabric with a SWIR hyperspectral camera and FT-NIR spectrometer. Each tested sample includes standardized 75 _l of 100 % blood. The results s…