Keywords: GSR SEM/EDX NAA Chemical ballistic Scientific Police of Algeria a b s t r a c tThis work is realized in view to determine appropriate techniques for the revelation of mineral gun shoot residues. Picked up from the crime scene, these indicial traces are used as material proofs for helping and guiding judicial investigations. As achievement of this process, two (02) technics were employed for mineral gun shoot residues, namely; Neutron Activation Analysis, and scanning electron microscopy/EDX. Samples of metallic powder residue were realized after several shoots by different kind of weapons with local and foreign ammunitions. So, this study was undertaken to develop chemical ballistic specialty in order to improve forensic investigations and drive benefit to Technical and ScientificPolice of Algeria to be use for judicial investigation.It turns out that the SEM/EDX method is more adequate to this type of investigation, despite the high sensitivity of the NAA. This is stated; NAA remains a complementary methods.

No abstract

No abstract

No abstract

Trace elements (TEs) constitute a major part of pollution, which can induce a detrimental impact on public health. A precise analysis of these elements in the environment is an important parameter in the evaluation of the population's quality of life. This work aims to quantify the concentration of some trace elments in enviromental samples using Istrumental Neutron Activation Analysis technique (INAA); also a comparative study between three sampling points (Draria, Baraki and Reghaia) were done. The Samples and standards were irradiated for 6 h at “NUR” research reactor with a thermal neutron flux of 1013 n cm−2 s−1, and analyzed by gamma ray spectrometry using HPGe detector. Seventeen elements were assessed: Ba, Br, Ce, Co, Cr, Hf, Fe, La, Nd, Rb, Sb, Sc, Se, Sm, Sr, Yb and Zn in this study. The accuracy of the method was evaluated by analyzing Certified Reference Materials (CRMs) and Standard Reference Materials (SRMs). The data obtained in this work may contribute to obtaining information about a possible rank of pollution and the different capabilities of elemental bioaccumulation by lichens.