Vacuum‐packed salmon was treated by electron beam irradiation preservation technology, to study the effects of electron‐beam irradiation on odor active compounds of salmon by two types of methods for extraction: headspace‐solid phase micro extraction (HS‐SPME) and solvent assisted flavor evaporation (SAFE). Volatile flavor compounds examined by gas chromatography‐mass spectrometry (GC‐MS) and gas chromatography‐olfactometry (GC‐O), combined with aroma extract dilution method (AEDA) and odor activity value (OAV) for identification of important odorants. In addition, the correlation between sensory attributes and volatile compounds of salmon irradiated at different doses was analyzed by partial least squares regression (PLSR). The results showed that after SPME and SAFE extraction, a total of 49 and 70 volatile flavor compounds were detected in salmon before and after electron beam irradiation. AEDA and OAV were further identified, among which 10 odorants were considered as important volatile flavor compounds and played an important role in the formation of aroma contours such as meaty, fatty, and grassy in salmon. In addition, methanethiol, 3‐methyl butyraldehyde, 3‐methyl propyl aldehyde, dimethyl disulfide, dimethyl trisulfide, and 2‐pentyl furan were identified as the important volatile flavor compounds in salmon irradiated with 4 kGy, and were also the unique compounds that constituted irradiation off‐odor. In general, salmon irradiated with 1 kGy showed the best aroma profile.Practical ApplicationSPME and SAFE were used as two types of extraction methods for volatile compounds of salmon, which complemented each other. Additionally, combined with AEDA and OAV, characteristic flavor compounds were identified. Furthermore, the odor fingerprint of salmon with E‐beam irradiation was established for the first time.

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The extraction and recycling of phenol from high concentration coal gasification wastewater has been studied using polypropylene (PP) hollow fiber membrane and polyvinylidene fluoride (PVDF) hollow fiber membrane as liquid membrane support, the mixture of tributyl phosphate (TBP) and kerosene as liquid membrane phase, and sodium hydroxide as stripping agent in the process of extraction. The experiments investigated the effect of the operating conditions of the hollow fiber supported liquid membrane, such as aqueous phase temperature and the connection forms of membrane modules, on the extraction efficiency of phenol from high concentration coal gasification wastewater. The conclusions obtained from lab scale experiments provided guidance for scale-up experiments. So, in the scale-up experiments, three membrane modules connected in parallel, then three membrane modules connected in series were used to increase the treatment capacity and improve the treatment effect, under the operating conditions of wastewater temperature 20 ˚C, PH 7.5~8.1, flow rate 100 L/h and the concentration of stripping phase 0.1 mol/L, stripping phase flow rate 50 L/h, the extraction efficiency of the PP-TBP supported liquid membrane system was 87.02% and the phenol concentration of effluent was 218.14mg/L. And the phenol concentration of effluent met the requirements of further biodegradation treatment.

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Polydimethylsiloxane (PDMS)/Polyvinylidene fluoride (PVDF) hollow fiber composite membrane was prepared by dynamic negative pressure method to treat coal to chemical wastewater containing high concentration of phenol, in which PVDF hollow fiber membrane acts as base membrane and PDMS as modified membrane. In the pilot scale experiment, the influence of aeration rate, temperature, flow rate, pressure under membrane on phenol removal efficiency were investigated and operating parameter optimized. At temperature 70 , flow rate of 150 L/h, pressure under membrane 5 KPa, gas-water ratio 0.3, 75 L coal to chemical wastewater containing phenol fluctuated between 1600 and 1800 mg/L was treated for 6h, and phenol removal efficiency reached 72%. The system ran stably for 120 h and performed well, phenol removal efficiency being kept more than 60%.