Many synthetic chemical fertilizers are said to increase yield for few years [benefit] but are said to make the land infertile or barren [loss] soon. This is apparent dual nature of technology.

Dual-use research refers to scientific research that can be used for both beneficial purposes, such as advancements in medicine or technology, and potentially harmful purposes, such as the creation of biological weapons. Scientists conducting dual-use research must carefully consider the ethical implications and potential risks associated with their work.

Dual channel process can use

Armitage Shanks is a manufacturer of bathroom fixtures such as sinks and toilets that use dual flush technology. In addition to this they manufacture plumbing supplies.

Yes - especially through the use of virtual machine technology. Otherwise, you can configure the laptop as a dual-boot machine.