UNC Resources Inc., a Falls Church manufacturer of nuclear and aerospace parts and machine tools, reported profits of $1.1 million (7 cents per share) for the quarter ended Sept. 30, compared with a net loss of $118,000 (1 cent) for the same quarter of 1983.

Revenue from continuing operations was $44.4 million, compared with $47 million a year earlier. The company, which also has interests in the minerals industry, gave much of the credit for the results to continuing strong performances by its UNC Naval Products, UNC Technical Products and UNC Nuclear Industries units.

For the nine months ended Sept. 30, the company had profits of $12.7 million (81 cents), compared with a net loss of $1.2 million (10 cents) in 1983. Revenue was $131.9 million, down from $168.4 a year before.

*NS&T Bankshares Inc., the parent company of NS&T Bank of the District, reported net income of $1.7 million ($1.21) for the third quarter, compared with $1.3 million (96 cents) a year before. The company said earnings were $4.698 million ($3.42) for the first nine months of 1984, compared with $4.2 million ($3.10) for the same period of 1983.

Total assets as of Sept. 30 were $859 million. Total loans were $493 million, and deposits were $615 million.

*First American Bank N.A. reported net income of $1.8 million (81 cents) for the third quarter of 1984, up from $1.2 million (54 cents) a year earlier. Profits for the first nine months were $5.1 million ($2.24), compared with $3.9 million ($1.71) in the comparable 1983 period.