FireChat may catch on as a way to corral revelers, but that's just the beginning of its practical applications. For political organizers, it could become a critically important way to keep protesters and activists connected when their traditional forms of communicating get cut off.
Desiccators are sealable enclosures containing desiccants used for preserving moisture-sensitive items such as cobalt chloride paper for another use. A common use for desiccators is to protect chemicals which are hygroscopic or which react with water from humidity.
In electronics, a comparator is a device that compares two voltages or currents and outputs a digital signal indicating which is larger.It has two analog input terminals and and one binary digital output. The output is ideally. A comparator consists of a specialized high-gain differential amplifier.They are commonly used in devices that measure and digitize analog signals, such as analog-to-digital converters (ADCs), as well as relaxation oscillators.pecific rail-to-rail comparators with p-n-p input transistors, like the LM139 family, allow input potential to drop 0.3 volts below the negative supply rail, but do not allow it to rise above the positive rail.