No abstract

Figure 1. Part of the NH-CJH region of the 300-MHz NOESY spec-trum (2K X 2K data matrix) of the decapeptide LHRH. The two framed regions 1 and 2 showing severe overlaps are also plotted on expanded scales. The corresponding regions from the NOESY TR spectrum (700 f, samples zero filled to 2K X 2K) exhibiting homonuclear decoupling in the uq dimension are shown in the frames V and 2'. No undesired cross peaks (see text) appeared in the NH-CJH region so suppression10 was unnecessary. N = 4 (see text) was sufficient in this experiment since the Ca protons can have at maximum three coupling partners, leading to the seven-step cycle ¡0°;0.

A new approach to detecting a weak photoacoustic signal in a gas medium is described. Instead of a gas-filled resonant acoustic cavity, the sound energy is accumulated in a high- Q crystal element. Feasibility experiments utilizing a quartz-watch tuning fork demonstrate a sensitivity of 1.2x10(-7) cm(-1) W/ radicalHz . Potential further developments and applications of this technique are discussed.

No abstract

No abstract