Alyonka Larionov is the host of Barclays Center TV, the in-house channel that will be featured on the 700 HDTV monitors that are everywhere around the Brooklyn arena. But she’s more than that. She will also be the face of the Nets social media offerings, particularly Social Cam, the mobile-friendly video app that the team is using to push out short pieces on the team and arena. Tuesday, she was in Fort Greene for Brook Lopez’s ceremonial shearing and has posted short videos from the “back stage” at the YES Network’s photo shoot and the opening of the Nets Shop. And for her Russian viewers, there was a tour of Brighton Beach.