中国南部四背景地区春季大气碳质气溶胶特征与来源

春季分别同时在中国南方4个背景地区(海南尖峰岭、香港鹤嘴、浙江临安和云南腾冲)进行大气加密观测实验,并分析其大气中PM2.5质量浓度及其碳质颗粒组分(有机碳(OC)、元素碳(EC)和左旋葡聚糖).结果表明,各区域背景站点由于受不同污染源及传输过程影响而呈现出不同的特征:西南部腾冲站点与东部临安站点由于分别受到生物质燃烧和化石燃料燃烧等一次污染源的主导影响,而形成高OC、EC水平特征,且经受体示踪物方法估算腾冲站点受生物质燃烧对其OC的贡献均值可达到73%;尖峰岭站点由于二次污染及活跃的生物活动的共同作用,表现了高OC/EC比值及低碳质颗粒物浓度的特征,而鹤嘴站点则主要受海洋气团影响呈现出低碳质颗粒浓度与两两呈高度相关的特点,反映了其所在区域春季的背景特征.     

Bio-removal of mixture of benzene, toluene, ethylbenzene, and xylenes/total petroleum hydrocarbons/trichloroethylene from contaminated water

Four pure cultures were isolated from soil samples potentially contaminated with gasoline compounds either at a construction site near a gas station in Fai Chi Kei, Macau SAR or in the northern parts of China (Beijing, and Hebei and Shandong). The e ects of di erent concentrations of benzene, toluene, ethylbenzene, and three isomers (ortho-, meta-, and para-) of xylene (BTEX), total petroleum hydrocarbons (TPH), and trichloroethylene (TCE), when they were present in mixtures, on the bio-removal e ciencies of microbial isolates were investigated, together with their interactions during the bio-removal process. When the isolates were tested for the BTEX (50–350 mg/L)/TPH (2000 mg/L) mixture, BTEoX in BTEoX/TPH mixture was shown with higher bio-removal e ciencies, while BTEmX in BTEmX/TPH mixture was shown with the lowest, regardless of isolates. The TPH in BTEmX/TPH mixture, on the other hand, were generally shown with higher bio-removal e ciencies compared to when TPH mixed with BTEoX and BTEpX. When these BTEX mixtures (at 350 mg/L) were present with TCE (5–50 mg/L), the stimulatory e ect of TCE toward BTEoX bio-removal was observed for BTEoX/TCE mixture, while the inhibitory e ect of TCE toward BTEmX for BTEmX/TCE mixture. The bio-removal e ciency for TPH was shown lower in TPH (2000 mg/L)/TCE (5–50 mg/L) mixtures compared to TPH present alone, implying the inhibitory e ect of TCE toward TPH bio-removal. For the mixture of BTEX (417 mg/L), TPH (2000 mg/L) along with TCE (5– 50 mg/L), TCE was shown co-metabolically removed more e ciently at 15 mg/L, probably utilizing BTEX and/or TPH as primary substrates.     

病死猪厌氧发酵特性研究

为提高病死猪厌氧发酵甲烷转化率和挥发性固体降解率,实现病死猪的无害化处理向资源化利用方向转变,选择温度和接种比例2个关键因素进行厌氧发酵试验。温度选择35℃和55℃,接种比例按照接种物与底物的挥发性固体质量比分别确定为0∶10、1∶9、2∶8、3∶7、4∶6、5∶5、6∶4、7∶3、8∶2、9∶1、10∶0,采用序批式发酵。研究发现,发酵试验至不同水平,试验都进入停止产气期,此时测定发酵液相代谢产物成分,以优化工艺参数。试验结果表明,病死猪厌氧发酵最佳工艺条件为接种物与底物的挥发性固体质量比为5∶5,温度为35℃,该最佳工艺条件下挥发性固体甲烷产率为271 m L/g,挥发性固体降解率为63.4%。     

UASB-SBR工艺处理高浓度有机农药废水中试研究

介绍了UASB-SBR组合新工艺处理高浓度难降解有机农药废水技术。针对湖北沙隆达农药公司清污分流后的浓污水COD浓度高,可生化性差,运行费用高的情况,先采用UASB处理技术,COD去除率平均达到58.3%,可生化性系数由0.26左右提高到0.34左右,色度去除率平均为70%;接着采用SBR技术做接口试验,COD去除率平均达到84.5%。废水处理成本由行业3~5元/kgCOD降低为1元/kgCOD。     

产蛋白酶中度嗜盐菌Thalassobacillus sp. SY-7的分离、鉴定及发酵条件优化

为促进嗜盐微生物及其所产蛋白酶的工业应用,采用脱脂奶粉培养基从我国天津近海盐田富集筛选得到产蛋白酶中度嗜盐菌株SY-7.通过对其形态特征、生理生化、16S rRNA基因序列及系统进化树进分析,确定菌株的分类.利用Plackett-Burman(PB)设计和响应面优化法(Response surface methodology)优化其发酵条件.结果表明:菌株SY-7为革兰氏阳性菌,最适生长温度为30℃、最适生长pH 7.5,最适NaCl为10%.16S rRNA基因序列分析显示,菌株SY-7与Thalassobacillus devorans亲缘性最近,16S rRNA基因序列相似性为98.88%.利用PB设计从众多影响因素中筛选出影响较大的3个因素:葡萄糖含量、接种量和装液量;再利用响应面法中的杂合设计进优化,通过拟合得到响应曲面函数,获得了最佳的产酶条件.在该实验条件下酶活从870 U/mL提高到1 390 U/mL,实际酶活力达到理论预测值的98.3%,优化效果较好.