核磁小白，看到一篇原位固体核磁测反应动力学的文献，感觉对我很有用，想用他的方法，但是对他的实验不是很明白，实验部分如下：

The solid acid catalyst was H-USY zeolite (Si/Al = 11; 4.33 mmol H/g)characterized and used in a previous study.
2-methyl propane-2¹³C(iC4-¹³CH) and 2-methyl propane-2d (iC4-CD) were synthesized in thelaboratory.
A 50/50 mixture of the two gases was prepared for all in situ MASNMR experiments, which showed a final composition iC4-¹³CH/iC4-CD/iC4-CH of 42:53:5 according to NMR analyses.
A specific homemade device was used to activate the catalyst, load the gazeous starting material, and seal the 4 mm NMR rotor without exposure to ambient atmosphere prior to each experiment.
Around 50 mg of H-USY zeolite (0.216 mmol H) was first treated at 250 °C/54h and subsequently outgassed at room temperature for 3 h (<10-⁷mbar),and then, 0.5 mL of the gaseous mixture iC4-13CH/iC4-CD (0.4 mmol iC4/g)was introduced.
Time resolved 1H and 13C{1H} MAS were performed on a 500 MHzBruker NMR spectrometer equipped with a conventional 4 mm MAS probehead withinthe 297-327 K temperature range.
我看我们的4mm的转子容积很小，好像上面写的是90μL，请问这0.5ml气体是怎么装进去的啊