1st Generation Pesticides: 1  2500 BC- farmers began using the toxic chemical sulfur to kill off pests from their crops. 2  15th century AD -a variety of chemicals such as, arsenic, hydrogen cyanide, mercury and lead were put to use. 17th century -nicotine sulfate, derived from tobacco leaves was discovered as an effective pesticide and ants were controlled with mixtures of honey and arsenic.
Cell phones communicate with nearby cell towers mainly through radiofrequency (RF) waves, a form of energy in the electromagnetic spectrum between FM radio waves and microwaves. Like FM radio waves, microwaves, visible light, and heat, they are forms of non-ionizing radiation.
There are many data communication technologies that use low power radio waves to transmit data, including: * CDMA (used in most cell phones)* FM (used in Family Radio Service â¦ walkie talkie)* frequency-hopping spread spectrum (FHSS) (used in Bluetooth)* direct-sequence spread spectrum (DSSS), used in IEEE 802.15.4, which in turn is used by ZigBee, MiWi, 6LoWPAN, etc.* amateur radio operators often try QRP operation (very low power) with many different communication technologies: CW ...