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We investigate the possibility of a spontaneous collapse of the nuclei constituting the water molecule. We show that, due to a practically exact agreement of the energy of the p + p + 16O threshold and a resonance state of the 18Ne nucleus, the probability of nuclear fusion involving p + p + 16O → 18Ne*(4.522, 1-) in the rotationally excited H2O molecule is significantly enhanced. The calculation of the fusion probability is performed using a scheme analogous to the linear combination of atomic orbitals (LCAO), well known in the theory of molecules. [ABSTRACT FROM AUTHOR]

Morphological and genetic data for the Iberian golden-striped salamander, Chioglossa lusitanica, demonstrate the existence of two groups with southern and northern ranges, connected by a zone of intergradation in central Portugal. Because reproductive isolation between them is incomplete we consider the groups to be subspecies. The type locality of C. lusitanica (Buçaco near Lousã) is situated inside the mixed zone. This necessitates identification of the nominotypical subspecies. We sequenced a fragment of mitochondrial DNA from one of the species' syntypes and we determined what position over a latitudinal transect maximizes the morphological discrimination between the groups. Both approaches indicate that C. lusitanica from Buçaco represents the southern subspecies. A new subspecies of C. lusitanica is described from a northern locality (Valongo near Porto in north-western Portugal). A lectotype is designated for Chioglossa lusitanica. [ABSTRACT FROM AUTHOR]

This activity allows students to visualize the electrolysis of water in a microfluidic device in under 1 min. Instructional materials are provided to demonstrate how the activity meets West Virginia content standards and objectives. Electrolysis of water is a standard chemistry experiment, but the typical laboratory apparatus (e.g., Hoffman cell) is best suited for group presentations. With microfluidics, the cell volume is reduced from 100 mL to 100 µL, making the electrolysis safer and easier to view by an individual. A single device is reusable and assembled for $5. This report describes the development of a microfluidic learning module that was implemented and assessed in the eighth-grade chemistry classroom. [ABSTRACT FROM AUTHOR]

Abstract: Measurements at appropriate spatial and temporal scales are essential for understanding and monitoring spatially heterogeneous environments with complex and highly variable emission sources, such as in urban areas. However, the costs and complexity of conventional air quality measurement methods means that measurement networks are generally extremely sparse. In this paper we show that miniature, low-cost electrochemical gas sensors, traditionally used for sensing at parts-per-million (ppm) mixing ratios can, when suitably configured and operated, be used for parts-per-billion (ppb) level studies for gases relevant to urban air quality. Sensor nodes, in this case consisting of multiple individual electrochemical sensors, can be low-cost and highly portable, thus allowing the deployment of scalable high-density air quality sensor networks at fine spatial and temporal scales, and in both static and mobile configurations. In this paper we provide evidence for the performance of electrochemical sensors at the parts-per-billion level, and then outline results obtained from deployments of networks of sensor nodes in both an autonomous, high-density, static network in the wider Cambridge (UK) area, and as mobile networks for quantification of personal exposure. Examples are presented of measurements obtained with both highly portable devices held by pedestrians and cyclists, and static devices attached to street furniture. The widely varying mixing ratios reported by this study confirm that the urban environment cannot be fully characterised using sparse, static networks, and that measurement networks with higher resolution (both spatially and temporally) are required to quantify air quality at the scales which are present in the urban environment. We conclude that the instruments described here, and the low-cost/high-density measurement philosophy which underpins it, have the potential to provide a far more complete assessment of the high-granularity air quality structure generally observed in the urban environment, and could ultimately be used for quantification of human exposure as well as for monitoring and legislative purposes. [Copyright &y& Elsevier]