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41.
Gel ink pens have become a common writing instrument in the United States. Questioned document examiners often attempt to optically differentiate gel inks from each other and from other non-ballpoint ink writings (e.g., those from roller-ball pens). Since early formulations were primarily pigment-based, they do not elute when analyzed by thin-layer chromatography. However, recent gel ink formulations (i.e., within the past five years) include dye-based inks that can be easily separated. This study differentiates black gel inks using optical and chemical techniques. The techniques include: microscopy, visible and near infrared reflectance, near infrared luminescence, thin-layer chromatography (TLC), spot tests, and gas chromatography/mass spectrometry (GC/MS). As a result of this study a flow chart has been developed allowing for a systematic determination of a questioned ink. In addition, an analysis of volatile compounds found in gel inks revealed that there are some unique ingredients that may be found in gel inks that are not typically found in other non-ballpoint inks. 相似文献
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Kerley KR Copes H 《International journal of offender therapy and comparative criminology》2004,48(1):65-84
Criminologists increasingly have studied the effects of criminal justice contact on a broad range of offenders' adult outcomes. However, virtually all of this research focuses exclusively on street-level offenders. With the use of a unique data set that includes street-level and white-collar offenders, we investigated the odds of regaining steady employment following criminal justice contact by offender type. Specifically, we investigated the effects of age of onset, number of prior arrests, total time sentenced, timing of first arrest, and timing of first incarceration on employment stability for both types of offenders, while controlling for family background factors, race, educational attainment, and age. Overall, we found that white-collar offenders are better able to rebound following contact with the criminal justice system. However, when the accrue multiple arrests and are arrested or incarcerated before the age of 24, white-collar offenders face the same obstacles to employment stability as their street-level counterparts. 相似文献
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LaPorte GM Wilson JD Mancke SA Payne JA Ramotowski RS Fortunato SL 《Journal of forensic sciences》2003,48(5):1163-1171
Thermal transfer printing refers to printing processes that utilize heat to produce an image by either physical or chemical means or by a combination of both. As the technology has improved and the supplies have become less expensive, the use of thermal printing in the personal and business markets has increased significantly. Specifically, dye diffusion thermal transfer and thermal mass transfer have become predominant in the production of counterfeit credit cards, drivers' licenses, and other types of documents produced on plastic media. Chemical analysis by means of thin layer chromatography (TLC) has proven to be useful in characterizing various types of inks (e.g., writing and inkjet inks). In this study, the authors examined 81 different samples that included a total of 54 printer samples (43 photographic prints on paper and eleven plastic card samples) and 27 printer ribbons. A new TLC method was developed and tested utilizing a solvent system (80% n-hexane, 3% methyl ethyl ketone, and 17% ethyl acetate) that is capable of producing excellent resolution. 相似文献
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Weaver RK 《Social security bulletin》2003,65(4):38-56
Sweden's new multipillar pension system includes a system of mandatory fully funded individual accounts. The Swedish system offers contributors more than 600 fund options from a variety of private-sector fund managers. However, in the most recent rounds of fund choice, more than 90 percent of new labor market entrants have not made an active choice of funds and thus have ended up in a government-sponsored default fund. The Swedish system offers a number of lessons about implementing a mandatory individual account tier. Centralized administration keeps administrative costs down but requires considerable lead time. A very large number of fund options are likely to be offered unless strong entry barriers are in place. Engaging new labor market entrants in fund choice is likely to be difficult. A significant percentage of those making an active fund choice may choose funds that are very specialized and risky. Finally, special care must be devoted to designing a default fund and continual consumer communication. 相似文献
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For the first time, the UK Criminal Justice Act (1991) allowed the videotaped evidence of a child to be substituted for the child's evidence-in-chief in a criminal court. The present study is an evaluation of that legislation. One hundred and fifty children were observed testifying in a criminal court in the UK. The use of the videotaped evidence and subsequent cross-examination of the child witness (usually via the closed circuit television system) was also observed. The data base from the Lord Chancellor's Department of all trials involving child witnesses in England and Wales was also analysed. The results showed that the introduction of the video technology into the criminal courts reduced the levels of stress of child witnesses but did not increase the conviction rates. 相似文献
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