半衰期：衰变
参考

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↑  Gearbox Software. . PlayStation 2. 2001. Dual Access. Rosenberg: I've been talking with Harold, he seems to be under the impression you're planning on running the anti-mass spectrometer at greater than 90 percent. You realise there is a reason for the safety buffer. / Richard Keller: I understand your concern doctor, but the administrator was quite clear. / Rosenberg: The administrator is a bureaucrat, not a scientist! I did not design this equipment to be run at such high intensity! / Richard Keller: This is not your decision! Now if you want to stay and monitor the experiment, so be it, otherwise you can go back to your little labs by the trainyard.
↑  Gearbox Software. . PlayStation 2. 2001. Dual Access. Rosenberg: Well, we've got to get everyone out of here! Reach the surface, call for help, something! / Richard Keller: No! We've got the deal with the problem! We can't expect anyone else to understand the importance of resetting those dampening fields. Without those in place the dimensional gash could tear so wide it may never be repaired. / Rosenberg: Its too dangerous! If we fail, who will warn everyone else? We can have soldiers here in two hours to secure the facility and bring everyone to safety. Our concern must be for the people of Black Mesa. / Richard Keller: Perhaps you're right. Dr. Cross and Dr. Green may have survived, if so they can help us.
↑  Gearbox Software. . PlayStation 2. 2001. Domestic Violence. Richard Keller: The dimensional rift between here and the alien world must be sealed! We'll need to have a satellite in orbit in order to orchestrate a resonance reversal. The signal room for the satellite is nearby. Unfortunately the delivery rocket cannot launch without the all-clear codes. Now, any security guard in this dorm complex should have the codes we need. Go through the dorms and find a security guard, I'll take the tram around to the north side where we can pick you up.
↑  Gearbox Software. . PlayStation 2. 2001. Rift. Richard Keller: Gina? Colette? You'll be alright. You were caught for a moment in a harmonic reflux. Its one the swirling eddies in the space between two displacement event currents, although I can't imagine who was creating the other current. But it doesn't matter now! Rest my friends, we did it!
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《衰变》是半衰期系列中的唯一一个多人合作游戏，《衰变》默认运行于分屏模式。
Colette Green和Gina Cross于《衰变》中；《衰变》拥有半衰期系列中最高的模型质量和画质。