Method for selectively detecting multiple groups and/or molecules simultaneously by preparing multiple nuclear spin singlet and/or singlet orders

A pulse sequence method for realizing selective detection of multiple groups and/or molecules by simultaneously preparing nuclear spin singlets and/or singlet orders of the multiple groups and/or molecules, wherein, said method realizes precise excitation of multi-frequency magnetic resonance signals by utilizing optimization control methods, realizes the simultaneous selective detection of magnetic resonance signals of the multiple groups and/or molecules by simultaneously preparing the nuclear spin singlets and/or singlet orders of the multiple groups and/or the molecules, said method comprises the following core steps:

• Step i:
• simultaneously converting multiple groups and/or molecules from a thermal equilibrium state into a singlet and/or singlet orders through the pulses;
• Step ii:
• eliminating the non-singlet and/or non-singlet orders signals in the system by applying the gradient field;
• Step iii:
• simultaneously converting the nuclear spin singlets and/or singlet orders of the multiple groups and/or molecules into the observable states and collecting the magnetic resonance signals, and realizing simultaneous selective observation of multiple groups and/or molecules.