主题：【求助】样品检测方法问题！谢谢。

这个方法是做顶空的吗？
各位老师，帮帮忙，小弟是新手。

这是整个气相方法：
TESTS
pH (2.2.3): 6.5 to 7.5.
Dissolve 0.20 g in carbon dioxide-free water R and dilute to
10 mL with the same solvent.
Impurity C. Gas chromatography (2.2.28).
Silylation solution. To 2 mL of N,O-bis(trimethylsilyl)tri-
fluoroacetamide R add 0.04 mL of chlorotrimethylsilane R
and mix.
Test solution.Dissolve50.0mgofthesubstancetobeexamined
in 3 mL of water R and add 0.5 mL of hydrochloric acid R.
Extract with 2 quantities, each of 5 mL, of methylenechlorideR.
Evaporate the combined methylene chloride extracts to dryness
in a vial with a screw cap and add 0.5 mL of the silylation
solution.Sealthevialandheatat70±5°Cfor20min.
Reference solution (a).Dissolve5.0mgof sodium
phenylbutyrate impurity C CRS in methylenechlorideR and
dilute to 10.0 mL with the same solvent.
Reference solution (b). Dilute 1.0 mL of reference solution (a)
to 10.0 mL with methylenechlorideR.Place1.0mLofthis
solution in a vial with a screw cap, evaporate to dryness and
add 0.5 mL of the silylation solution. Seal the vial and heat at
70±5°Cfor20min.
Reference solution (c). Dissolve 10 mg of the substance to be
examined in 25 mL of water R. To 3 mL of this solution add
0.1 mL of hydrochloric acid R. Extract with 2 quantities, each
of 5 mL, of methylene chloride R. Combine the methylene
chloride extracts in a vial with a screw cap and add 2 mL of
reference solution (a). Evaporate to dryness and add 0.5 mL of
the silylation solution. Seal the vial and heat at 70 ± 5 °C for
20 min.
Column:
— material :fusedsilica;
— size: l =25m,?=0.25mm;
— stationary phase: poly(dimethyl)(diphenyl)siloxane R (film
thickness 1.0 μm).
Carrier gas : helium for chromatography R.
Flow rate:0.9mL/min.
Split ratio: 1:100.
Temperature:
                        Time(min)        Temperature(°C)
Column              0-5                50
                          5 - 27              50 → 270
                        27 – 32            270
Injection port                            270
Detector                                    270
Detection:flameionisation.
Injection:1 μL.
Relative retention with reference to phenylbutyrate (retention
time = about 20 min) : impurity C = about 0.98.
System suitability: reference solution (c) :
— resolution: minimum 3.0 between the peaks due to
impurity C and phenylbutyrate.
Limit :
— impurity C:notmorethantheareaofthecorresponding
peak in the chromatogram obtained with reference
solution (b) (0.1 per cent).
Related substances. Liquid chromatography (2.2.29). 

气相这个方法是不是顶空方法，如果是的话，里面怎么没有顶空条件？难道是硅烷化反应的条件就包含了顶空条件（Seal the vial and heat at 70 ± 5 °C for 20 min.）还是说顶空条件要自己摸索？