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The use of a new technique, Fourier transform infrared (FTIR) chemical imaging, has been demonstrated for the enhancement of latent fingermarks on a number of surfaces. Images of untreated fingermarks on glass backgrounds with excellent ridge detail were acquired using infrared chemical imaging. High quality fingermarks on glass backgrounds were also developed using ethyl cyanoacrylate (super glue) fuming and subsequent infrared chemical imaging. This new method allows the collection of images from backgrounds that traditionally pose problems for current fingermark detection methods. The background may, for example, be highly colored, have a complex pattern, or possess other pattern or image characteristics that make it difficult to separate fingermark ridges using traditional optical or luminescent visualization. One background that has proven to be a challenging surface for the development of latent fingermarks is the Australian polymer banknote. To demonstrate the power and applicability of infrared chemical imaging, fingermarks fumed with ethyl cyanoacrylate were successfully imaged from Australian polymer banknotes.

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Chemical imaging technology is a rapid examination technique that combines molecular spectroscopy and digital imaging, providing information on morphology, composition, structure, and concentration of a material. Among many other applications, chemical imaging offers an array of novel analytical testing methods, which limits sample preparation and provides high-quality imaging data essential in the detection of latent fingerprints. Luminescence chemical imaging and visible absorbance chemical imaging have been successfully applied to ninhydrin, DFO, cyanoacrylate, and luminescent dye-treated latent fingerprints, demonstrating the potential of this technology to aid forensic investigations. In addition, visible absorption chemical imaging has been applied successfully to visualize untreated latent fingerprints

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This paper examines the potential of infrared chemical (hyperspectral) imaging as a technique for the forensic analysis of automotive paint chips in particular, and multicomponent (e.g., layered) samples in general. Improved sample preparation procedures for the infrared analysis of paint chips are detailed, with the recommendation that where mounting resins are chemically incompatible with the sample, it is better to mount and section the sample in a soft wax from which the sections can be removed and pressed into a KBr disk for transmission analysis. Infrared chemical images of multilayered paint chips have been successfully obtained, with the chief advantage over conventional infrared analysis being that thousands of infrared spectra are collected in a few minutes across the whole sample, at a spatial resolution of around 5 µm. As with conventional infrared spectroscopy, chemical species can be identified from their spectra, but the wealth of information available can be also extracted in a number of different ways that make multicomponent spectral (and hence chemical) comparisons between two samples easy to visualize and understand. In one approach, the infrared chemical images of two paint chips being compared side-by-side can be viewed as a “movie,” in which each frame is an intensity map of the two samples at a given wavenumber (frequency) value. In another approach, the spectra (pixels) in the image files are classified into chemically similar groups, resulting in a “cluster” image that makes it possible to simultaneously compare all of the layers in two paint chips. These methods are applicable to other multicomponent samples, and also to other chemical imaging techniques

A dual Banach space X is Kadec-Klee in the weak * topology if weak * and norm convergence of sequences coincide in the unit sphere of X. We shall consider a stronger, uniform version of this property. A dual Banach space X is uniformly Kadec-Klee in the weak * topology (UKK*) if for each e > 0 we can find a ó in (0, 1) such that every weak '-compact, convex subset C of the unit ball of X whose measure of norm compactness exceeds e must meet the (1-<5)-ball of X. We show in this paper that Cx(ß7), the space of trace class operators on an arbitrary infinite-dimensional Hilbert space %? is UKK*. Consequently Cx(ßf) has weak "-normal structure. This answers affirmatively a question of A. T. Lau and P. F. Mah. From this it follows that C, (ßf) has the weak '-fixed point property.

Nanoparticles (NPs) have been used in numerous fields such as medicine, imaging, and electronics to cite just a few. In forensic science, NPs have been researched specifically for the detection of fingermarks. Their small size, surface functionalization ability, and luminescence properties can potentially lead to better resolution, increased sensitivity, and selectivity. This paper offers an extensive review of the various NP types investigated over the past three decades. NPs are sorted into seven categories, namely metal, metal oxide, quantum dots (QDs), carbon dots (C‐dots), silica (SiO2), and upconverters NPs (UCNPs) as well as a miscellaneous section. Each type is discussed in details from a critical viewpoint. The most promising NP types are also identified. This article is categorized under: Forensic Chemistry and Trace Evidence > Fingermarks and Other Marks