Abstract: A method and an apparatus are described to focus sharply a wide range of particle sizes for particles suspended in a relatively high flow rate of carrier gas. The particles are accelerated through a continuously converging ladder of smooth contractions, each designed such that: (i) the flow remains laminar at substantial Reynolds numbers; (ii) a certain band of particle sizes is focused in each contraction, without substantial defocusing of larger particle focused in one or several preceding contractions; (iii) the form, length, and ratio of entry to exit diameter of each contraction, as well as the number of consecutive contractions are chosen such that all particles within a given relatively wide range of sizes are focused at the end of the ladder of contraction steps into a relatively narrow focal region. The focusing apparatus coupled to a collector device constitutes a new type of virtual impactor, termed a focusing virtual impactor, which can also be used as a powerful particle concentrator.

Abstract: An apparatus and method for improving the performance of an Internet website includes a performance processor that identifies a plurality of critical performance factors that facilitate improved website performance and then tests in real time, by utilization of an application programming interface, the influence of individual ones of said plurality of performance factors by application of a fractional factorial design.

Abstract: In one embodiment, the present disclosure provides fail-safe mechanisms for final filters. The fail-safe mechanisms of the present disclosure include a prefilter that is essentially transparent or translucent to TOC contaminants and a microporous filter downstream from the prefilter that filters contaminants by means of size-exclusion, mechanical interception, coagulation, or a combination thereof, the filter being adapted to significantly reduce fluid flow and undergo blockage under a challenge by TOC contaminants.

Abstract: A filter and filter material for providing or treating potable water is provided. The filter includes a housing having an inlet and an outlet, a filter material disposed within the housing, the filter material formed at least in part from a mixture of a plurality of mesoporous and microporous activated carbon particles. Preferably, at least some of the mesoporous activated carbon filter particles are coated with a cationic polymer, and even more preferably, at least some of the particles are coated with a cationic polymer and silver or a silver containing material. Kits comprising filters and information relating to the reduction, killing or removal of bacteria, viruses, microbials, and TTHM are also provided.