Abstract: Methods for producing economical antimicrobial and antifungal nanoparticle composites are presented. The method includes converting chitosan or derivative thereof to nanoparticles by ionotropic gelation process and the nanoparticle composite in the presence of a process solution without any separation process to isolate the nanoparticles prior to application. The composition containing chitosan nanoparticles, ionotropic gelation agent, a nonionic surfactant, and an active halogen provides improved disinfectant and fungicidal properties against bacterial, viral and fungal contaminants along with prolonged residual effects. Methods and systems for decontamination, wound healing and plant growth enhancements are also presented.

Abstract: A water treatment system is described in which an inlet is in fluid communication with an outlet. A first region including a halogen release system is located downstream from the inlet and upstream from the outlet. A second region including chitosan or a chitosan derivative is located downstream from the first region and upstream from the outlet. A filter including a housing containing the water treatment system is also described. A method for treating water in which water flows through the water treatment system is also described.

Abstract: Methods for producing or regenerating an iodinated anion exchange resin are presented. The methods include treating an iodide loaded anionic resin with an aqueous solution comprising an in situ formed I2 to produce the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to resins produced by conventional methods. Methods and systems for purifying water are also presented.

Abstract: A filter to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, a filter material comprising chitosan or a derivative thereof intermediate the halogen release system and the outlet, and a scavenger barrier intermediate the filter material and the outlet. The filter material may comprise a chitosan-halogen complex. The filter material is capable of regeneration during periods of stagnation. The filter may have a Log reduction value for viruses of at least 4 and a Log reduction value for bacteria of at least 6.

Abstract: Methods for producing or regenerating an iodinated anion exchange resin are presented. The methods include treating an iodide loaded anionic resin with an aqueous solution comprising an in situ formed I2 to produce the iodinated resin. The iodinated resins show reduced and stable levels of iodine elution compared to resins produced by conventional methods. Methods and systems for purifying water are also presented.

Abstract: A water treatment system may generally comprise a generally cylindrical halogenated resin bed comprising an empty bed contact time greater than 1 second, an aspect ratio less than 0.8, and a fluid velocity less than 0.5 cm/s, wherein the aspect ratio is the ratio of the length of the halogenated resin bed to the diameter of the halogenated resin bed; and wherein the fluid velocity is the quotient of the volumetric flow rate of the water treatment system and the cross-sectional area of the halogenated resin bed; and wherein the halogenated resin bed improves the removal of contaminates relative to a corresponding water treatment system having an aspect ratio greater than 0.8.

Abstract: The water treatment systems may generally comprise multiple halogens and chitosan or derivatives thereof as well as methods of making and using the same. A water treatment system to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, and a halogenated chitosan intermediate the halogen release system and the outlet. The system may comprise a scavenger barrier intermediate the halogenated chitosan and the outlet. The halogen release system may comprise a first halogen having a first oxidizing potential. The halogenated chitosan may comprise a second halogen having a second oxidizing potential. The second oxidizing potential is greater than the first oxidizing potential.

Abstract: A filter to provide potable water may generally comprise an inlet in fluid communication with an outlet, a halogen release system intermediate the inlet and the outlet, a filter material comprising chitosan or a derivative thereof intermediate the halogen release system and the outlet, and a scavenger barrier intermediate the filter material and the outlet. The filter material may comprise a chitosan-halogen complex. The filter material is capable of regeneration during periods of stagnation. The filter may have a Log reduction value for viruses of at least 4 and a Log reduction value for bacteria of at least 6.

Abstract: A filter having a flow path for a filtrate may generally comprise an iodinated resin, wherein the iodinated resin releases iodine into the filtrate, and an ion exchange column downstream from the iodinated resin, the ion exchange column comprising at least one ion exchange resin, wherein the at least one ion exchange resin progressively changes color as iodine is absorbed from the filtrate, and an indicator to indicate when the amount of iodine in the iodinated resin reaches a predetermined lower threshold. Other embodiments include methods of using embodiments of the filter described herein.

Abstract: A water treatment system may generally comprise a generally cylindrical halogenated resin bed comprising an empty bed contact time greater than 1 second, an aspect ratio less than 0.8, and a fluid velocity less than 0.5 cm/s, wherein the aspect ratio is the ratio of the length of the halogenated resin bed to the diameter of the halogenated resin bed; and wherein the fluid velocity is the quotient of the volumetric flow rate of the water treatment system and the cross-sectional area of the halogenated resin bed; and wherein the halogenated resin bed improves the removal of contaminates relative to a corresponding water treatment system having an aspect ratio greater than 0.8.

Abstract: A circuit and method for signalling between chips implements signal transter through a power supply line. Parallel data bits are serialized into a serial data stream and sent from a source semiconductor device through the power supply line to a destination semiconductor device. The destination semiconductor device receives the serial data stream and, using a high pass filter, selects the high-frequency component of the power supply line, and deserializes the serial data stream into parallel bits. A low pass filter interconnecting the power supply line and the chip provides a steady power supply potential to operate the functional elements of the chip.

Abstract: A Doppler shift detector for determining the Doppler shift between a transmit signal and a receive signal uses clocked delay lines. The clocked delay lines count the number of edges in an applied signal thereto (e.g. the receive signal) at various positions in the delay line in accordance with a clock signal. Period detection logic ascertains the mean position of counted edges and thence the period of the applied signal. The Doppler shift is then calculated from the measured periods of the transmit signal and receive signal. The delay line for the receive signal is clocked by either the receive signal itself or the transmit signal.

Abstract: A self calibrated time delay circuit including a plurality of serially connected unit delay cells each having an output tap which is selectable, a registration means for simultaneously determining the status of each output node of each of the unit delay cells, combinatorial and sequential logic units for analyzing said registration means and sending error correction commands to an up/down controller, said up down controller providing a command code for controlling the delay of each said unit delay by selecting which tap is output from said unit delay cell.

Abstract: Apparatus for formation of a two-phase shift register bit that preserves noise margins, allows use of reduced standby power, requires only two clock phase signals to drive the system, and requires relatively few transistors for implementation. In one embodiment, the apparatus uses two modules that are substantially identical, each module using four transistors and requiring only a single clock phase signal for operation.

Abstract: A programmable computer shift register or other time delay means of variable length that provides time delays that are integral multiples of a predetermined time delay unit .DELTA.t, that uses relatively few switches, that controls time delays introduced by passage of signals through multiple-state switches that are in different states.

Abstract: A circuit is provided which modifies a digital drive signal to produce a time variant drive signal for application to a gate of a bus driver transistor. The circuit's purpose is to reduce the amplitude of ringing on a bus, due to rapid discharging of current from the bus, in order to prevent unintentional triggering of devices connected to the bus. A P-channel MOS transistor and N-channel MOS transistor are connected so that the digital drive signal is simultaneously applied to the source of the P-channel MOS transistor and to the drain of the N-channel MOS transistor. The gate of the driver transistor is connected to the drain of the P-channel MOS transistor and the source of the N-channel transistor.

Abstract: An on-board integrated circuit chip signal source which allows operation of the chip from previously incompatible and excessively high amplitude signal sources, and as well powers the chip from such sources as the input signal, a clock, etc. The invention utilizes a 3 plate capacitor, with the bottom plate formed of a heavily doped region of the silicon substrate. Signal is applied between the outside plates of the capacitor and a proportion of the signal is received between the center plate and one of the outside plates. A diode clamp connected between the center plate and a reference potential fixes the derived peak and average signal levels.