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    We can express thoughts and feelings and send sounds and pictures on our smart phones today. We also communicate by using programs like Skype and Face Time. We can't send tastes, smells or touch, of course. But scientists in Britain are trying to develop a way for smart phones to do just that.

    Adrian David Cheok is a professor at City University in London. He wants people to experience communication using all of their senses. He said "In the real world, we can open up the glass, open the window. We can touch, we can taste, we can smell in the real world."

    To give users a sense of taste, researchers designed two electrodes (电极）that are placed on the tongue. A chemical process creates different tastes through molecules (微粒)on the surface of the tongue. This chemical process sends electrical signals that convince the brain that a person is tasting something. They have already created sour, salty, sweet and bitter tastes.

    "You put these two silver electrodes in your mouth, you put your tongue in between and then it stimulates electrically your tongue and you get a virtual taste perception in your brain."

    A device(设备）called "Scentee" permits users to have the sense of smell. Scentee plugs into a smart phone and can spray tiny clouds of fragrances, including flowers, fruits and coffee. Professor Cheok says the person speaking can activate the device.

    Scentee holds a container with about 100 different smells. The container must be replaced when all the scents（pleasant smells) run out.