Abstract: A liquid treatment method includes mixing a liquid with an agent to form a mixture, aging the mixture to obtain to a predetermined condition in at least one of the liquid and the agent, and dispensing the aged mixture. An interaction between the liquid and the agent causes the predetermined condition to occur. Also, a majority of the aging occurs while the mixture is in a dynamic state. A related system includes a mixer receiving a liquid and a drag reducing agent and an aging module connected to the mixer. The mixer disperses the drag reducing agent in the liquid to form a mixture and the aging module has a flow path along which the mixture flows. The flow path has a distance sufficient for a majority of the aging to occur while the mixture is in a dynamic state, wherein the aging changes the drag reducing agent to a predetermined condition.

Abstract: A liquid treatment method includes mixing a liquid with an agent to form a mixture, aging the mixture to obtain to a predetermined condition in at least one of the liquid and the agent, and dispensing the aged mixture. An interaction between the liquid and the agent causes the predetermined condition to occur. Also, a majority of the aging occurs while the mixture is in a dynamic state. A related system includes a mixer receiving a liquid and a drag reducing agent and an aging module connected to the mixer. The mixer disperses the drag reducing agent in the liquid to form a mixture and the aging module has a flow path along which the mixture flows. The flow path has a distance sufficient for a majority of the aging to occur while the mixture is in a dynamic state, wherein the aging changes the drag reducing agent to a predetermined condition.

Abstract: A point-of-sale (POS) module and associated methods are described for performing a transaction involving a check. The POS module interacts with one or more add-in modules. Each add-in module is associated with a particular method for processing a payment using a check. Accordingly, the POS module can accommodate multiple different workflows by plugging in appropriate add-in modules.

Abstract: A point-of-sale (POS) module and associated methods are described for performing a transaction involving a check. The POS module interacts with one or more add-in modules. Each add-in module is associated with a particular method for processing a payment using a check. Accordingly, the POS module can accommodate multiple different workflows by plugging in appropriate add-in modules.

Abstract: This invention is a self-contained NO.sub.x sensor assembly. It may be used to detect NO.sub.x levels in a flowing gas stream such as might be found in an exhaust gas from a combustion process and to produce a measurable electrical output related to the content of NO.sub.x measured. The NO.sub.x sensor assembly is of a configuration that may be detached from a mounting and replaced. The sensor assembly comprises two sensor elements one of which is made up of a catalyst on a temperature measuring device. The other is a gas stream ambient temperature measuring device. The catalyst is selected and configured so that it selectively reduces NO.sub.x and the resulting heat of the reaction raises the temperature of the allied temperature measuring device. The sensor assembly also contains a NO.sub.x reductant source. The sensor assembly may be placed in a moving vehicle for measuring NO.sub.x levels in its exhaust gas.

Abstract: This invention is a process for detecting low levels of nitrogen oxides (NO.sub.x) in a flowing gas stream (typically an exhaust gas stream) and a catalytic NO.sub.x sensor which may be used in that process.