James on "how do i concatenate the string to allow for the site name to be completed dynam"

For my client sites i have a little developer plugin i have created, giving clients contact details etc, and cleaning up a few other WordPress things.... with this i'm trying to add a button to the WP Admin bar for clients to raise support requests, and struggling to add the `bloginfo(name)' to the email subject field (highlighted in bold below).... how do i concatenate the string to allow for the site name to be completed dynamically?

$wp_admin_bar->add_menu( array(
        'id' => 'support-request',                // an unique id (required)
        'parent' => 'custom-support-menu',           // false for a top level menu
        'title' => 'Raise Support Request',     // title/menu text to display
        'href' => 'mailto:support@emailaccount.com?subject=<strong>Client%20Site</strong>%20Support%20Request',
        'meta' => array( 'target'=>'_blank' ),  // target for link
    ) );

Advice and explanation very much appreciated