Alex says that the secretary will disseminate the participant list to everyone.
"To disseminate" means to distribute, or to circulate, to give something to many different people.
For example, if you want to disseminate information about your party, you might put up posters, signs, send emails, or make telephone calls to let people know about your party.
To give information out to people is to disseminate the information.
The secretary is going to disseminate, or send, the list of the people who were at the meeting; we call this the "participant list."
A "participant" (participant) is someone who is part of something, someone who "participates" in something.
Alex officially ends the meeting by saying, "For now, I'm adjourning this meeting."
"To adjourn" (adjourn) is a formal verb that means to end or stop something, usually a meeting.
After someone adjourns a meeting, you might stay in the room for a while, talking to other people who are there, but when the meeting is adjourned, it is over - it is officially finished.
Alex says, "We will see each other again next Tuesday," reminding people of that the next meeting will be on Tuesday.
Finally, he thanks everyone for their participation.