Analysis of Indian blue ballpoint pen inks tagged with rare-earth thenoyltrifluoroacetonates by inductively coupled plasma-mass spectrometry and instrumental neutron activation analysis

Characterization and assessment of inks on sensitive documents for absolute/relative age determination is the challenging forensic problem in spite of practical difficulties. Tagging of ballpoint pen ink with suitable taggant(s) is a unique method to come out with definitive inferences on the detection of forgery in documents written with ballpoint pens. Selection of a proper taggant primarily depends on sensitivity of analytical determination and their absence in normal varieties of ink used for document writing. Rare-earth elements, from all technical considerations can be potential taggant(s) for inks. To ensure more compatibility with ink, 13 rare-earth thenoyltrifluoroacetonate chelates were prepared and characterized. The ballpoint pen inks were tagged with rare-earth thenoyltrifluoroacetonate chelates individually at about 1-100 ppm level depending on sensitivity of element under suitable optimized experimental conditions and instrumental sensitivity. Aliquots of such tagged ink having varying amounts of taggants were analyzed by ICP-MS and INAA. Satisfactory recoveries and a good linear relationship of intensity (signal) against concentrations/amounts were observed. Under the optimized experimental conditions, the detection limits were worked out. This study of tagging metal ions in combination with ICP-MS and NAA as an analytical tool can allow to draw various combination options based on different rare-earth chelates as suitable materials for tagging of ballpoint pen inks for absolute/relative age determination to aid in document related crime examination. The advantages and limitations of proposed analytical techniques are discussed.     

The Gender Gap in Educational Attainment in India: How Much Can Be Explained?

Differential treatment of sons and daughters by parents is a potential explanation of the gender gap in education in developing countries. This study empirically tests this explanation for India using household survey data collected in urban Uttar Pradesh in 1995. We estimate educational enrolment functions and selectivity-corrected educational attainment functions, conditional on enrolment. The gender difference in educational attainment is decomposed into the part that is explained by men and women's differential characteristics and the part that is not so explained (the conventional 'discrimination' component). The analysis suggests that girls face significantly different treatment in the intra-household allocation of education - there is a large unexplained component in the gender gap in schooling attainment. A detailed decomposition exercise attempts to discover the individual factors most responsible for the differential treatment.