Other unconventional liquid hydrocarbons include production from oil sands, ultra-heavy oils, gas-to-liquids technologies, coal-to-liquids technologies, biofuel technologies, and shale oil.Unconventional natural gas can be of several types.ther unconventional liquid hydrocarbons include production from oil sands, ultra-heavy oils, gas-to-liquids technologies, coal-to-liquids technologies, biofuel technologies, and shale oil.
Unlike standard headphones, which use relatively large drivers (speakers) and fit on top of or around your ears, or earbuds, which use fairly small drivers and sit loosely in your outer ears, in-ear-canal headphones use very small drivers and actually fit inside your ear canals (thus the name canalphones).
Photo: My trusty Etymotic ER-6 noise-isolating earbud headphones. These work by passive noise cancelling: each earpiece has a pair of (washable) plastic suction cups that make a tight seal in your ear canal to stop noise getting in and music leaking out. If you prefer, you can pull off the plastic cups and use disposable, soft foam ones instead.