Note 10 - Segment Information - Summary of Segment Information (Details) - USD ($)	12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue	$ 2,965,406	$ 3,676,785
Segment operating income	(819,896)	30,335
Total assets	2,138,728	3,089,825
Chemical [Member]
Revenue	1,101,016	1,258,890
Segment operating income	(407,230)	(49,966)
Total assets	791,329	1,050,541
Electronics [Member]
Revenue	1,512,692	1,883,251
Segment operating income	(371,103)	(65,271)
Total assets	1,090,751	1,575,811
Engineering [Member]
Revenue	351,698	534,644
Segment operating income	(41,563)	145,572
Total assets	$ 256,648	$ 463,473