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Early and on-site detection of environmental contaminations and physicochemical parameters of seawater is increasingly preferred to guarantee hazard minimization in many settings. In this paper, we describe a combination of microfluidic paper-based sensors (µPADs) and an Android-based smartphone application (App) for simultaneous on-site quantification of phosphate (PO

Experiments were conducted to investigate the effectiveness of a range of fingermark visualisation processes on brand new, uncirculated, £5 polymer banknotes (and their test note predecessors), as produced by the Bank of England (BoE). In the main study of this paper, a total of 14 individual processes were investigated on BoE £5 polymer banknotes, which included both ‘Category A’ processes (as recommended in the Home Office Fingermark Visualisation Manual) as well as recently developed processes, including fp Natural ® 2 powder (cuprorivaite) from Foster + Freeman and a vacuum metal deposition sequence that evaporates silver followed by zinc. Results from this preliminary investigation indicate that fp Natural ® 2, multimetal deposition, Wet Powder ™ Black, iron oxide powder suspension and black magnetic powder are the most effective processes on these uncirculated £5 BoE polymer banknotes, when viewed under “primary viewing” conditions (white light or fluorescence). Additional fingermarks were visualised on the polymer banknotes following the subsequent use of reflected infrared imaging and lifting techniques, and with the benefit of these techniques taken into consideration, the aforementioned processes remained amongst the most effective overall. This work provides initial insight into fingermark visualisation strategies for BoE £5 polymer banknotes, and the need for further studies in order to generate mature operational guidance is emphasised.

Introduction The purpose of this study was to evaluate the effects of intraradicular moisture conditions on the push-out bond strength of root canal sealers. Methods Eighty root canals were prepared using rotary instruments and, thereafter, were assigned to 4 groups with respect to the moisture condition tested: (1) ethanol (dry): excess distilled water was removed with paper points followed by dehydration with 95% ethanol, (2) paper points: the canals were blot dried with paper points with the last one appearing dry, (3) moist: the canals were dried with low vacuum by using a Luer adapter for 5 seconds followed by 1 paper point for 1 second, and (4) wet: the canals remained totally flooded. The roots were further divided into 4 subgroups according to the sealer used: (1) AH Plus (Dentsply-Tulsa Dental, Tulsa, OK), (2) iRoot SP (Innovative BioCeramix Inc, Vancouver, Canada), (3) MTA Fillapex (Angelus Industria de Produtos Odontologicos S/A, Londrina, Brasil), and (4) Epiphany (Pentron Clinical Technologies, Wallingford, CT). Five 1-mm-thick slices were obtained from each root sample (n = 25 slices/group). Bond strengths of the test materials to root canal dentin were measured using a push-out test setup at a cross-head speed of 1 mm/min. The data were analyzed statistically by two-way analysis of variance and Tukey tests at P = .05. Results Irrespective of the moisture conditions, iRoot SP displayed the highest bond strength to root dentin. Statistical ranking of bond strength values was as follows: iRoot SP > AH Plus > Epiphany ≥ MTA Fillapex. The sealers displayed their highest and lowest bond strengths under moist (3) and wet (4) conditions, respectively. Conclusions The degree of residual moisture significantly affects the adhesion of root canal sealers to radicular dentin. For the tested sealers, it may be advantageous to leave canals slightly moist before filling.

The objective of this study was to investigate the synthesis of zeolites from paper sludge ash, and to evaluate their applications for water purification to simultaneously remove NH4+ and PO43- in aqueous solution. Paper sludge ash had a low abundance of Si and a significant Ca content, due to the presence of calcite that was used as paper filler. Na2SiO3 was added to the NaOH solution to increase Si content in order to synthesize zeolites with high cation exchange capacity. The original ash without addition of Si yielded hydroxysodalite with a cation exchange capacity of ca. 50 cmol/kg. Addition of Si to the solution yielded Na-P1 (zeolite-P) with a higher cation exchange capacity (ca. 120 cmol/kg). The observed concentrations of Si and Al in the solution during the reaction explain crystallizations of these two phases. The product with Na-P1 could simultaneously remove NH4+ and PO43- from the solution between pH 4 and 9.

Metal pollution of soils is a great environmental problem. The major risks due to metal pollution of soil consist of leaching to groundwater and potential toxicity to plants and/or animals. The objective of this study is to evaluate by means of chemical and ecotoxicological approach the effects of paper mill sludge addition on the mobile metal fraction of polluted metal soils. The study was carried out on acidic soil derived from mining activities and thus polluted with heavy metals, and on two paper mill sludges having different chemical features. The results obtained by leaching experiments showed that the addition of a paper mill sludge, consisting mainly of carbonates, silicates and organic matter, to a heavy-metal polluted soil produces a decrease of available metal forms. The carbonate content seems to play a key role in the chemical stabilisation of metals and consequently in a decrease of toxicity of soil. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover a lasting effect.

Soluble silicates, commercially known as waterglass, are among the largest volume synthetic chemicals in the world. Silicon from waterglass is rapidly transformed to the biologically active orthosilicic acid (referred to as dissolved silicate). This paper aims to assess the impact of waterglass on the aquatic environment in Western Europe. The emission to surface waters from the four most relevant application areas, household detergents, pulp and paper production, water and wastewater treatment, and soil stabilization, is estimated to be ca. 88-121 kton of SiO2 per year. This is a small fraction (