[Pollution Characteristic and Control Factor Analysis of Atmospheric Ozone During Summer Typical Periods in Linyi, Shandong].

In June 2020, an observation experiment of O3 and its precursors was carried out in Linyi City, Shandong Province. Based on the observation data and MCM photochemical model simulation, the formation mechanism and control mechanism of an ozone pollution case in mid-June were analyzed. The study found that, despite the high precipitation during the observation period, ozone concentrations rapidly accumulated and exceeded the limits once the weather cleared, with the 1-h average and 8-h φ (O3) exceeding the national ambient air quality standards on 10 days (32% in frequency)and 14 days (45%), respectively. The diurnal variation in O3 concentration was unimodal and accompanied by the afternoon peak at 16:00. MCM simulation results showed that the daily net reaction rate of O3 was 20×10-9 h-1, and HO2·+NO and RO2·(except CH3O2·)+NO contributed 49.0%-51.1% and 37.3%-40.2% of O3 generation, respectively. The contribution of the·OH+NO2 reaction to the total consumption of O3 was 35.1%-57.4%. The results of VOCs reactivity, relative incremental reactivity (RIR), and the EKMA curve method showed that the generation of O3 was more sensitive to alkenes (mainly trans-2-pentene and trans-2-butene)and aromatics (mainly m/p-xylene and toluene)but was negatively sensitive to NOx. In other words, the reduction in VOCs concentration would lead to the decrease in O3 concentration, whereas the reduction in NOx concentration would lead to the increase in O3 concentration. PMF source analysis results showed that volatile sources used by solvents and vehicle exhaust emissions contributed significantly to the above key precursor VOC species. Considering the titration effect of NO from vehicle exhaust emissions on ozone, controlling the use of volatile sources of solvents can realize the control of O3 pollution accurately and efficiently.

Lentinan dose dependence between immunoprophylaxis and promotion of the murine liver cancer.

Lentinan could exhibit significant biological activity favorable for human health and disease control such as the recovery of patients with liver cancer. In order to investigate the effect of lentinan dose dependence between immunoprophylaxis and promotion of cancer cell proliferation of the murine liver cancer, different concentrations of lentinan were prepared for the test in vitro (MTT assay) and in vivo (cumulative survival assay, spleen lymphocyte proliferation tests and peritoneal macrophage phagocytosis assays). New emerging proteins of the H22 cell incubated with lentinan was demonstrated by MS analysis and protein database searching. Lentinan was non-toxic for HL7702 cells but inhibited H22 cells proliferation obviously in a dose-dependent manner. In vivo, the proliferation of H22 hepatocarcinoma cells was inhibited by lentinan 0.4mg/kg body weight (L2, survival rate, 20%, PPP<0.01). Six proteins 60Sacidic ribosomal protein P2, Peroxiredoxin-2, Annexin A5, PDZ and LIM domain protein 1, Src substrate cortactin and Moesin were found as emerging proteins of the H22 cell incubated with high dose lentinan which related to cancer promotion closely. In conclusion, Thelentinan was relatively safe and could inhibit the proliferation of H22 cancer cells through immunity improvement when it's intake was in proper quantity.