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In the process of fingerprint development Physical Developer has been largely the method of choice on porous surfaces after coming into contact with wet environments. It is only recently that a new technique has been identified which could replace this standard technique. This study aims to build on previous research and expand knowledge regarding the technique. The study built on previous research and compared Physical Developer to Oil Red O, testing both on four paper types, while being placed in three different water types and an accelerant for various amounts of time. Marks were placed with both heavily ‘loaded’ sebaceous fingers and ‘normal’ un-washed fingers. Results show that Oil Red O consistently produced clearer more detailed marks from the ‘loaded’ fingers, but neither technique proved to work better on the ‘normal’ marks. Neither technique developed any prints from the accelerant.

The fabrication of SERS substrates, which can offer the advantages of strong Raman signal enhancement with good reproducibility and low cost, is still a challenge for practical applications. In this work, a simple three-dimensional (3D) paper-based SERS substrate, which contains plasmonic silver-nanoparticles (AgNPs), has been developed by the silver mirror reaction. This paper strip was characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), etc. Pretreatment of the paper as well as the reaction time, temperature, and reagent concentrations for the silver mirror reaction were varied for further studies. With the optimized experimental parameters, the AgNPs synthesized and distributed in-situ on the paper strip could give more favorable SERS performance. The limit of detection (LOD) as low as 10(-11)M for Rhodamine 6G (R6G) and 10(-9)M for p-aminothiophenol (p-ATP) plus wide linear range for the log-log plot of Raman intensity versus analyte concentration were achieved. The detection of R6G in rain water was also carried out successfully. The merits of this protocol include low cost, easy operation, high sensitivity and acceptable stability, which make it ideal for the detection of environmental samples in trace amounts.

An examination of the relative breakdown rates of unused toilet paper, facial tissues and tampons was undertaken in nine different environments typical of Tasmanian natural areas. Bags of the paper products (toilet paper, facial tissues, tampons) were buried for periods of 6, 12 and 24 months at depths of 5 and 15 cm. A nutrient solution simulating human body wastes was added to half of the samples, to test the hypothesis that the addition of nutrients would enhance the breakdown of paper products buried in the soil. Mean annual rainfall was the most important measured variable determining mean breakdown in the nutrient addition treatment between sites, with high rainfall sites (mean annual rainfall of greater than 650 mm) recording less decayed products than the drier sites (mean annual rainfall of 500-650 mm). Temperature and soil organic content were important influences on the breakdown of the unfertilised products. Toilet paper and tissues decayed more readily than tampons. Nutrient addition enhanced decay for all products across all sites. Depth of burial was not important in determining the degree to which products decayed. In alpine environments, burial under rocks at the surface did not increase the speed of decay of any product. The Western Alpine site, typical of alpine sites in the Tasmanian Wilderness World Heritage Area, showed very little decay over the two-year period, even for nutrient enhanced products. Management prescriptions should be amended to dissuade people from depositing human toilet waste in the extreme (montane to alpine) environments in western Tasmania. Tampons should continue to be carried out as currently prescribed.

An extensive network of gummed paper collectors was used during the 1950s for routine monitoring of radioactive fallout from weapons testing. The experiments reported in this paper were designed to examine the collection efficiency of gummed paper for wet deposition of several types of soluble and insoluble radioactive contaminants under conditions similar to those found during natural rainstorms. The collection efficiencies for each substance were determined over a range of rainfall amounts and at two separate rainfall intensities. The collection efficiency of the gummed paper is highest for large insoluble particles and lowest for soluble ionic substances. The values for 7Be and 131I ranged from about 0.30 (30%) at 2.5 mm of rain to 0.04-0.06 (4%-6%) at 20 mm of rain. These values were negatively correlated with the amount of rain and were unaffected by rain intensity. This suggests that the collection efficiency of either ion is simply a matter of rapid saturation and runoff. Neither rain amount nor rain intensity has much effect on the collection efficiency of large insoluble particles. These particles seem to settle readily onto the surface of the gummed paper from which they are not easily removed by additional rain. Analysis of the collection efficiencies of the gummed paper included the activity of both the gummed paper and the standing water on the paper. A large portion of the activity for the ionic substances was found in the standing water. There was less activity by insoluble particles in standing water. This indicates that for estimates of deposition of soluble substances, considerable bias could be introduced into the results if the standing water is discarded prior to analysis.