Cambridge Electronic Industries Plc believed it has won environmental control equipment maker Tace Plc with an increased offer of eight new shares for every five Tace, valuing the latter at 306 pence a share, just under UKP30m: Cambridge is claiming irrevocable acceptances for 50.5% of the shares, but rival bidder Thermo Electron Inc, offering 255 pence cash a share is not so sure that irrevocable really means what it says in this case.