Unit Instruments Inc. shares surged 39% after the maker of parts for semiconductor manufacturing equipment said it's in talks to be acquired. Yorba Linda-based Unit Instruments didn't identify the buyer or disclose other details on the proposed transaction. Its shares rose $2.56 to close at $9.13 in Nasdaq trading. Earlier, the stock hit $10.75, its biggest gain since changing its name from Autoclave Engineers Inc. on Nov. 17, 1995. Any sale would need approval from shareholders.