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971.
Polycyclic aromatic hydrocarbons(PAHs) and their nitrated derivatives(NPAHs) attract continuous attention due to their outstanding carcinogenicity and mutagenicity. In order to investigate the diurnal variations, sources, formation mechanism, and health risk assessment of them in heating season, particulate matter(PM) were collected in Beijing urban area from December 26, 2017 to January 17, 2018. PAHs and NPAHs in PM were quantitatively analyzed via gas chromatography-mass spectrometry(GC-MS). ...  相似文献   
972.
Food and Environmental Virology - Norovirus is a major cause of foodborne-associated acute gastroenteritis (AGE) outbreaks worldwide. Usually, food products are contaminated either during...  相似文献   
973.
Food and Environmental Virology - Enteric viruses have been described as important contaminants in fresh and ready-to-eat foods such as sandwiches, deli meat and dairy products. This is a...  相似文献   
974.
Herein, Na+ and Ca2+ are introduced to MnO2 through cation-exchange method. The presence of Na+ and Ca2+ significantly enhance the catalytic activity of MnO2 in toluene oxidation. Among them, the Ca-MnO2 catalyst exhibits the best catalytic activity (T50 = 194°C, T90 = 215°C, Ea = 57.2 kJ/mol, reaction rate 8.40 × 10?10 mol/(sec?m2) at 210°C. T50 and T90: the temperature of 50% and 90% toluene conversion; Ea: apparent activation energy) and possess high tolerance against 2.0 vol.% water vapor. Results reveal that the increased acidic sites of the MnO2 sample can enhance the adsorption of gaseous toluene, and the mobility of oxygen species and the content of reactive oxygen species in the catalyst are significantly improved due to the formed oxygen vacancy. Thus these two factors result in excellent catalytic performance for toluene oxidation combining with the weak CO2 adsorption ability.  相似文献   
975.
Experimental results from an isothermal laminar flow reactor at atmospheric pressure are presented on the chemical composition in the post-oxidative region of two sooting fuel-rich pre-mixed mixtures diluted in nitrogen. A base case composed of n-heptane and O2 in N2 at 1425 K with a C/O of 2.85 was perturbed by substituting 10% of the carbon in n-heptane with carbon as CH4. While these changes would intuitively reduce aromatics and soot formation by increasing H2 and decreasing C2H2 concentrations, we observe the opposite. The concentrations of individual aromatic species are observed to actually increase by up to 50% and the soot yield increases by 80%.  相似文献   
976.
Organic contaminants [polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenylethers (PBDEs), nonylphenols], organotin compounds and trace metals (cadmium, chromium, mercury and zinc) were determined in flounder (Platichthys flesus) liver and sediment from the Amsterdam harbour (North Sea Canal) and Rotterdam harbour (Euromonding) and off the Dutch coast between the Amsterdam and Rotterdam harbour mouths in order to assess the level of contamination in these harbours and to study contamination gradients.  相似文献   
977.
Journal of Material Cycles and Waste Management - Biofilters have been recognized as a key technology in the mitigation of greenhouse gases (GHG) emitted by landfills. This study aimed to evaluate...  相似文献   
978.
Journal of Polymers and the Environment - Polymers used as raw materials for synthetic packaging, i.e., those obtained from petroleum-derived sources, are resistant to degradation. Because of this,...  相似文献   
979.
Journal of Polymers and the Environment - Bioactive biodegradable films are emerging biomaterials in the food packaging field. This study aims to investigate the effect of different Cenostigma...  相似文献   
980.
Heart rot is a common soil-borne disease in the pineapple industry, but the situation can be alleviated by the application of bio-fertilizers with beneficial microbiomes. Clarifying the controlling mechanism of bio-organic fertilizer on the high incidence of heart rot is critical in monocultural pineapple cropping patterns. In our study, the soil of continuous cropping pineapple orchards was collected. Three types of carriers (rapeseed cake, peat soil, and coconut bran), biocontrol strains (Bacillus subtilis HL2 and Streptomyces strain HL3), and organic fertilizer (YJ) were composted into different bio-fertilizers (KC, KN, KY, LC, LN, and LY), which were used in pot experiments. The controlling effect of the bio-fertilizer was determined based on the response of pineapple heart rot and bacterial communities to different fertilizing methods. Our results revealed that the incidence of heart rot in bio-fertilizer KC was the lowest, which decreased by 20% and 13.3%, respectively, compared to HF (chemical fertilizer, 16-16-16) and YJ (organic fertilizer). The richness and diversity of soil bacterial communities in all biofertilized treatments (KC, KN, KY, LC, LN, and LY) were significantly higher than those in HF. However, the α-diversity indices of the bio-fertilizers (KC, KN, and KY) were higher than those of LC, LN, and LY, and the bacterial community composition was significantly different. The bacteria GP4, GP6, Bacillus, and Azohydromonas were enriched in KC, KN, and KY, while the relative abundance of Streptomyces increased significantly in LC, LN, and LY. Furthermore, Spearman correlation analysis showed that the relative abundance of these bacterial groups was significantly negatively correlated with the incidence of pineapple heart rot. In summary, the application of bio-organic fertilizers can decrease the incidence of pineapple heart rot by altering the soil bacterial community structure and stimulating beneficial soil microorganisms, which is important for reconstructing the ecological balance in continuous pineapple orchards. © 2022 Authors. All rights reserved.  相似文献   
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