<p> Bloodstain evidence can be obscured and lost when deposited on dark surfaces where there is no contrast between the bloodstain and the surface. This can also occur when criminals attempt to conceal bloodstains by painting over them. This research investigated the detection and visualization of bloodstains deposited on dark surfaces and concealed under paint with the use of an infrared (IR) alternate light source produced by the Foster and Freeman company under the name Crime-lite^&reg; 82S Infrared. </p><p> The results show that the Crime-lite^&reg; 82S Infrared in conjunction with an IR sensitive camera can aid in the detection and visualization of bloodstains best on porous surfaces such as indoor carpets and most clothing as well as on and under red-tinged paints with the more flat or matte finishes. The results also suggest the component within blood responsible for absorbing IR light is hemoglobin present in red blood cells. Further, the findings indicate that when hemoglobin is present in too low of a quantity, it falls below the detection threshold to absorb IR light and bloodstains will not be visualized. Given its ease-of-use and portability, combined with the support of the findings from this collaborative study with the Los Angeles Police Department (LAPD) Field Investigation Unit (FIU), the Crime-lite^&reg; 82S Infrared and camera is recommended as an additional tool in the search for bloodstain evidence that may otherwise go undetected.</p>

<p> Thin films (~100 nm) have been prepared of the prototypical spin-crossover complex Fe(phen)₂(NCS)₂ (phen = 1,10-phenanthroline). Initial attempts to prepare these films by direct vapor deposition yielded films of a different material. Through extensive FT-IR, Raman, UV-Vis, and x-ray photoelectron spectroscopy it is shown that these as-deposited films are the ferroin-based tris complex [Fe(phen)₃](SCN)₂. Structural characterization by AFM and powder XRD reveals them to be smooth and amorphous. When heated, the [Fe(phen)₃](SCN)₂ films are converted first to Fe(phen)₂(SCN)₂ and then to a third species postulated to be Fe(phen)(NCS)₂ which is likely a one-dimensional coordination polymer. On the other hand, deposition from Fe(phen)₂(NCS)₂ onto heated substrates produces a mixture of these three materials. The identity of the Fe(phen)₂(NCS)₂ films is proved by additional spectroscopic, structural, and magnetic characterization. Magnetometry reveals them to remain spin-crossover active albeit with a more gradual and incomplete spin-transition than the bulk material. The films are found to be granular in nature and deep crevices were observed at the grain boundaries. Within the optical microscope, the coloring of the grains is seen to be dependent upon sample orientation. Powder XRD indicates texturing of crystalline domains where the crystallographic c-axis is parallel to the surface normal. This represents a new process for production of Fe(phen)₂(NCS)₂ films.</p><p> With the aim of realizing the potential for spin-crossover materials to modulate electrical conduction and vise versa, electrical characterization has been performed as a function of temperature on vertical junction devices incorporating the prepared Fe(phen)₂(NCS)₂ films. In order to prevent penetration of the top electrode through the cracks and crevices in the organometallic layer, a multiple sequential deposition and annealing process was developed to produce films with a continuous surface topography. A small change in the weak electrical conductivity of these devices appears at the spin transition temperature, demonstrating for the first time in this important material a coupling of the electrical conductivity and magnetic spin state. Here, the HS state has a higher electrical conductivity. Incorporation of LiF interfacial layers between the Fe(phen)₂(NCS)₂ and the metal electrodes improves conduction slightly but tunneling still appears to be the current-limiting mechanism. Electrical measurements were also performed on devices made with the related complex [Fe(phen)₃](SCN)₂. Such films were much more conductive&mdash;as good as other typical organic semiconductor materials. All together, this work establishes the potential for this family of complexes to be incorporated into thin-film based electrical devices whose operation is based on the spin-crossover effect or otherwise.</p>

<p>Research concerning lignin has increased during the last years due to its renewability and ready availability in black liquor at pulp mills. Today, the kraft lignin found in black liquor is used as a fuel to gain energy in the recovery boiler at the mill. However, a new isolation concept, LignoBoost®, has enabled isolation of part of the lignin while allowing the use of black liquor as a fuel. This isolated lignin can be utilised as a fuel in, for example, thermal power stations or further upgraded to more value-added products. In this context, the most interesting value-added product is carbon fibre. The demand for carbon fibre has increased, but the biggest obstacle for a more extended use is the high production cost. About half of the production cost is related to the raw material.</p><p>In this work, the possibility of using kraft lignin as a precursor for carbon fibre production has been investigated through fundamental studies. Kraft lignins originating from birch, <em>Eucalyptus globulus</em>, softwoods and softwoods from liner production have been studied. By separating the lignin while still in solution in the black liquor, unwanted large particles such as carbohydrates can easily be removed. After isolation according to the LignoBoost process and purification with the use of an ion-exchanger, the lignins have been both chemically and thermally characterised. Identification of the released compounds at different temperatures has been performed because only 40% of carbon relative to original lignin remains, down from theoretical 60% after thermal treatment up to 1000°C. The main released compounds were phenols, as revealed by pyrolysis-GC/MS. Additionally, a pre-oxidation was done in order to try to stabilise the lignins. It was shown that an oxidation prior to the thermal treatment increases the yield by more than 10% and that the main release of compounds takes place between 400°C and 600°C. Fractionated lignin is better qualified as raw material for carbon fibre production because it is purer and its softening temperature can be detected. Fractionated kraft lignins from all investigated wood sources have high possibilities to act as precursors for the manufacture of carbon fibre.</p>

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