Time-resolved optical techniques (spectrograph, high-speed camera, photodiode) were used for scrutinizing the initial stages of the microwave discharge (2.45 GHz, 200–500 W) achieved in liquid alkanes (C_nH_2n + 2). Petroleum solvent Nefras S2 80/120 (a mixture of light hydrocarbons with boiling temperatures ranging between 33°C and 205°C) was considered to be representative of alkanes. The discharge was ignited in the liquid, at the end of a molybdenum antenna located under ambient conditions above the liquid. The discharge displaced sequences of light pulses of different shapes and amplitudes, randomly distributed in time. The minimum pulse duration is 0.5 ms. At times close to 1 ms, the spectrum comprises emission bands of the C₂ molecule, lines of hydrogen, and the C⁺ ion, but there is no continuum associated with the emission of the formed solid carbon-containing particles. In a number of cases, an anomalous spectrum of the C₂ molecule was recorded, with no such sequences having been observed before.

中文翻译：

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液态烃中微波放电在其发展初期的光发射

时间分辨光学技术（光谱仪、高速相机、光电二极管）用于检查在液态烷烃（C _n H _{2 n  + 2}）中实现的微波放电（2.45 GHz，200-500 W）的初始阶段。石油溶剂 Nefras S2 80/120（一种沸点在 33°C 到 205°C 之间的轻烃混合物）被认为是烷烃的代表。放电在液体中点燃，在位于液体上方环境条件下的钼天线末端。放电取代了不同形状和幅度的光脉冲序列，随机分布在时间上。最小脉冲持续时间为 0.5 ms。在接近 1 ms 的时间，光谱包括 C _{2 的}发射带分子、氢线和 C ⁺离子，但没有与形成的固体含碳粒子的发射相关的连续谱。在许多情况下，记录了 C ₂分子的异常光谱，以前没有观察到这样的序列。