detector(A mechanical, electrical, or chemical device that automatically identifies and records or registers a stimulus, such as an environmental change in pressure or temperature, an electrical signal, or radiation from a radioactive material)
detergent(A surface-active agent used for removing dirt and grease from a variety of surfaces and materials. Early detergents contained alkyl sulphonates, which proved resistant to bacterial decomposition, causing foaming in rivers and difficulties in sewage treatment plants. These hard detergents were replaced during the 1960s with soft biodegradable detergents. Apprehension continues to be expressed about the use of phosphates in detergents, helping to promote the process of eutrophication. No satisfactory substitute has yet emerged)