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Motivated by the need to prepare for the next generation of fingerprint spoofing, we applied the "proactive forensic science" strategy to the biometric field. The working concept, already successful in a few fields, aimed at adopting the sophisticated criminals' way of thinking, predicting their next move so that the crime‐fighting authorities can be one step ahead of them and take preventive measures, against biometric spoofing in this instance. This strategy involved the design, production, and characterization of innovative polymeric materials that could possibly serve in advanced fingerprint spoofs. Special attention was given to materials capable of fooling fingerprint readers equipped with spoof‐detecting abilities, known as "Presentation Attack Detection" (PAD) systems and often referred to as liveness detection. A series of direct cast fake fingerprints was produced from known commercially available spoofing materials, and was functionally tested to compare their performance with that of spoofs produced from the new polymers. The novel materials thus prepared were hydrogels based on polyethylene glycols (PEGs) that were chain‐extended. They showed good performance in deceiving security systems, considerably better than that of spoofs produced from commercial materials, and are, therefore, good spoofing candidates that law‐enforcement authorities should be aware of. [ABSTRACT FROM AUTHOR]

A study was conducted to characterize the synthesis of indandiones based on the oxygen-transfer agent, HOF.CH3CN. 1H and 13C nuclear magnetic resonance spectra were determined using a 200 MHz spectrometer while trimethylsilyl enol ethers were dissolved in chloroform. Results indicated that the oxidation of alcohols with HOF.CH3CN was associated with the abstraction of the hydrogen terminal to the hydroxy group.

X-Ray crystallography and electronic structure calculations using the correlation-consistent polarized valence double-xi (cc-pVDZ) basis set at the density functional theory (DFT) B3LYP were used to study the explosive properties of triacetone triperoxide (TATP) and diacetone diperoxide (DADP). The calculations predict that the explosion of TATP is not a thermochemically highly favored event and involves entropy burst.

Fingerprints have been detected and photographed by fluorescence for four decades. The technique has required the use of a barrier filter, in most cases orange, to block the light source reflection and isolate fluorescence. In some cases, however, the substrate also exhibits fluorescence, which can partially or totally obscure the fingerprint. A new narrow bandpass filter, used in combination with the standard barrier filter, can add significantly to both the extent and clarity of inherently and chemically treated fluorescing fingerprints. Moreover, in certain borderline cases, the chemical solution alone may be insufficient, but tailored optics can save the situation by converting an otherwise useless stain to an identifiable impression. [ABSTRACT FROM AUTHOR]

The title compound, [Cs(CH3COO)(C28H16O8)(C2H5OH)]·C2H5OH, is the product of the complexation between one vasarene analogue [1], bis ninhydrin naphthalene-1,3-diol and CsF, where the F- ion has reacted with residual acetic acid (AcOH), to form a [1]·CsOAc complex. The inter?molecular inter?actions with the multiple oxygen-containing functional groups of the ligand, as well as O-H⋯O hydrogen bonds involving the ethanol solvent mol?ecules, stabilize the complex, forming a chain along [100]. Additional parallel-displaced [π]-[π] stacking, with an inter?planar distance of 3.669 (1) Å, connect several unit cells in a three-dimensional supra?molecular structure, though, the larger size of AcO- (1.60 Å) compared to F- (1.33 Å) prevents the tight packing that was once achieved with other vasarene complexes of CsF. [ABSTRACT FROM AUTHOR]

The reaction between bis-ninhydrin resorcinol and benzyltrimethylammonium fluoride in ethanol has produced the title compound, 2C10H16N+·2C24H13O8-·-1.5H2O, which contains a unique centrosymmetric supramolecular dimeric entity, where two deprotonated ligands are held together via two strong and short [O···O = 2.4395 (13) Å] [O-H-O]- bonds of the type negative charge-assisted hydrogen bonds (-CAHB). The central aromatic rings of the ligands create parallel-displaced π-π stacking at an interplanar distance of 3.381 (1) Å, which helps stabilize the dimer. In the crystal, two symmetry-related solvent water molecules with a site occupancy of 0.75 are attached to the carbonyl groups of the dimer by weaker O-H···O hydrogen bonds, forming chains along [101]. [ABSTRACT FROM AUTHOR]