盐酸洛美沙星输入方式对水中反硝化过程的影响     

杨美萍  何江涛  邹华  邓璐  张金刚 《地球科学与环境学报》2022,(1):78-90

为探究环境中抗生素输入方式对反硝化过程的影响,选择盐酸洛美沙星(LOM)为代表抗生素,以纳米乳化油为碳源,开展了LOM浓度(200 ng·L-1和2 mg·L-1)与输入方式(一次输入和两次输入)不同组合条件下的反硝化模拟实验.结果表明:相同输入方式下,高浓度体系对NO-3-N还原的抑制率比低浓度体系高;相同浓度不同输...  相似文献   

生物活性元素Fe来源及其溶解度影响因素研究综述     

杜志恒  效存德  李向应 《地球科学进展》2013,28(5):597-607

具有生物活性的元素Fe被认为限制了海洋生物生产力,其在海洋生态系统中的生物地球化学循环对全球碳循环起到调节作用,全球40％～50％的海洋因“高叶绿素低营养盐”(HNLC)“缺Fe”而初级生产力较低.然而,关于生物活性元素Fe的研究不仅涉及海洋科学,还与大气科学、环境科学、地球科学等学科紧密联系.近些年,围绕生物活性元素“Fe”开展的研究不仅是地球科学领域的前沿问题,还是海洋学家与环境学家共同关注的热点问题.目前,尽管对于生物活性元素Fe的研究已取得很大的进展,但模型、室内实验及野外观测之间仍存在很大的挑战与不确定性.系统地总结了生物活性元素Fe最重要的自然来源方式,详细介绍了影响生物活性元素Fe溶解度的主要因素,最后,对将来的工作提出建议,为我国未来开展类似的研究提供参考.  相似文献   

Purification and photodynamic bioactivity of phycoerythrin and phycocyanin from Porphyra yezoensis Ueda     

Chuner Cai  Yuan Wang  Chunxia Li  Ziye Guo  Rui Jia  Weining Wu  Yan Hu  Peimin He 《中国海洋大学学报(英文版)》2014,13(3):479-484

Phycoerythrin and phycocyanin were purified from Porphyra yezoensis Ueda with their bioactivity determined in this study. Continuous precipitation with ammonium sulfate at different concentrations （10%, 20%, 40%and 50%） increased the purity （A564：A280） of phycoerythrin to 1.49, 3.92 fold of the raw extract （0.38） and the purity （A615：A280） of phycocyanin to 0.70, 3.33 fold of the raw extract （0.21）. Two more times of chromatography with hydroxylapatites finally made the purity of phycoerythrin and phy-cocyanin reach 5.50, 14.47 fold of the raw extract, and 5.10, 24.29 fold of the raw extract, respectviely. The yield of high purity phycoerythrin and phycocyanin were 0.21%and 0.09%of dried P. yezoensis blade, respectively. The photodynamic cytotoxic ex-periment showed that both phycoerythrin and phycocyanin inhibited the growth of liver tumor cells significantly. It was found that 250 mg L-1 purified phycoerythrin and phycocyanin inhibited the growth of hepatocellular carcinoma cells 24 h after laser-irradiation by 80%and 59%, respectively, and 100 mg L-1 purified phycoerythrin and phycocyanin induced the apoptosis of 31.54%and 32.54%of the cells, respectively, 8 h after photodynamic therapy. Oue findings demonstrated that P. yezoensis can serve as photosensitizer （phycoerythrin and phycocyanin） producer.  相似文献   

青岛沿海生物气溶胶中微生物活性的粒径分布特征     

谢佳敏  祁建华  高冬梅 《中国海洋大学学报(自然科学版)》2020,50(8)

为了解生物气溶胶中微生物活性的粒径分布特征,于2017年3月～2018年2月在青岛地区连续采集了生物气溶胶分级样品,运用荧光素二乙酸脂(FDA)水解法测定了样品中的微生物活性。结果表明,大于7μm粒子中的微生物活性有明显的季节变化(P0.05),表现为夏季最高,春、秋季次之,冬季最低。除5月外其余月份不同粒径段粒子中的微生物活性存在显著差异(P0.05),尤其是粗粒径段(大于2.1μm),可能与温度、湿度等影响有关。微生物活性比例呈现随粒径增加而增大的偏态分布,在大于7μm粒径范围内所占比例最高,平均为40.15%。气团来源对微生物活性的粒径分布具有影响,中部气团来源样品在3.3～4.7μm粒径范围内微生物活性所占比例较南方和北方气团来源样品明显降低。相关性分析显示,采样期间大于4.7μm粒子中的微生物活性与温度呈正相关(P0.01),2.1～3.3μm粒子中的活性与O_3浓度呈正相关(P0.05),微生物活性与其他气象因子和污染物因子无显著相关(P0.05)。  相似文献   

Inhibitory activity of an extract from a marine bacterium Halomonas sp. HSB07 against the red-tide microalga Gymnodinium sp. （Pyrrophyta）     

刘娟  李富超  刘玲  姜鹏  刘兆普 《中国海洋湖沼学报》2013,31(6):1241-1247

In recent years, red tides occurred frequently in coastal areas worldwide. Various methods based on the use of clay, copper sulfate, and bacteria have been successful in controlling red tides to some extent. As a new defensive agent, marine microorganisms are important sources of compounds with potent inhibitory bioactivities against red-tide microalgae, such as Gymnodinium sp. （Pyrrophyta）. In this study, we isolated a marine bacterium, HSB07, from seawater collected from Hongsha Bay, Sanya, South China Sea. Based on its 16S rRNA gene sequence and biochemical characteristics, the isolated strain HSB07 was identified as a member of the genus Halomonas. A crude ethyl acetate extract of strain HSB07 showed moderate inhibition activity against Gymnodinium sp. in a bioactive prescreening experiment. The extract was further separated into fractions A, B, and C by silica gel column chromatography. Fractions B and C showed strong inhibition activities against Gymnodinium. This is the first report of inhibitory activity of secondary metabolites of a Halomonas bacterium against a red-tide-causing microalga.  相似文献   

菱铁矿催化过氧化氢过硫酸钠修复地下水中TCE时对微生物的影响     

刘雅莉  刘菲  黄伟英 《地学前缘》2014,21(4):186-190

地下水中存在着一定量的土著微生物,为了了解类芬顿氧化去除地下水中三氯乙烯(trichloroethylene, TCE)时对微生物的影响,实验利用某污水处理厂好氧段活性污泥和水的混合物作为供试微生物,选择菱铁矿催化过氧化氢过硫酸钠的氧化体系,通过监测微生物的FDA(Fluorescein Diacetate,简称FDA)活性、TCE的浓度等指标,揭示该氧化体系对微生物的影响及存在TCE时微生物与TCE的相互影响。研究结果表明,该氧化体系会导致微生物的酶活性丧失,氧化剂体积与含微生物污水体积的比值(V氧∶V污)越大,对微生物的致死率越高。当V氧∶V污=1.2∶1时,即过氧化氢和过硫酸钠的浓度分别为0.1 mol/L和0.004 2 mol/L时,致死率为50%。当存在TCE时,也会导致微生物酶活性的丧失,随着TCE浓度的增加,对微生物的致死率越高。反之,微生物存在时,对该体系修复TCE几乎没有影响。  相似文献   

垃圾渗滤液污染场地NO_3~-、PO_4~(3-)和SO_4~(2-)对微生物活性的影响     

董军  许超  孙艳  孙玥  孙惠森 《吉林大学学报(地球科学版)》2009,39(6)

通过实验研究垃圾渗滤液污染场地N、S、P和湿度等因素对微生物活性的影响.结果表明：同时添加N和P后,土壤和细砂中微生物活性分别在第7 天和第14 天达到最大值0.685和0.588,有机质质量分数分别降低了10.97%和22.1%,平均降解速率分别为0.405和0.190 mg/(kg·d);添加NO_3~-后,土壤和细砂中有机质质量分数分别减少了10.3%和28.9%;添加SO_4~(2-)后,土壤和细砂中有机质质量分数分别减少了8.87%和28.4%;另外,湿度为50%和60%时,土壤中微生物活性的最大值分别为0.259和0.266,有机质平均分解速率分别为0.195和0.305 mg/(kg·d).因此,N、S、P和湿度对地下环境中微生物的活性有重要影响.  相似文献   

沙区植被恢复对土壤微生物量及活性的影响   总被引：3，自引：3，他引：0  

石万里  王辉  马维伟 《中国沙漠》2017,37(3):507-513

土壤微生物是生态系统功能及养分循环的关键影响因素,对土壤质量变化有重要的指示意义。研究了干旱沙区植被恢复过程中土壤微生物量及微生物活性的变化特征及其季节动态。结果表明：固沙植被区土壤微生物量碳氮和土壤基础呼吸显著大于流动沙丘,总体上表现为同一土层土壤微生物量碳氮和基础呼吸速率随植被恢复年限的延长而增加,而同一年代植被区则随土层深度的增加而减小。土壤微生物代谢熵随固沙年限的延长呈下降趋势,随土层深度的增加而增大。土壤微生物量和基础呼吸呈现出明显的季节变化,表现为夏季 >秋季 >春季 >冬季,且随着恢复年限的延长其变化幅度增大;微生物代谢熵不存在明显的季节变化。土壤微生物属性能够较好地反映沙区植被恢复引发的土壤质量变化。  相似文献   

纤蛇纹石在纳米材料及环境科学中的意义   总被引：7，自引：1，他引：7       下载免费PDF全文

王长秋王丽娟  鲁安怀 《岩石矿物学杂志》2003,22(4):409-412

传统工业矿物——纤蛇纹石，是一种具有独特卷管状构造的一维纳米管材料，具有机械强度好、耐热、绝缘等优良性能，同时具有高表面化学活性和生物活性。其活性主要源自表面不饱和键、纳米晶体巨大的比表面积所带来的高表面能以及卷曲构造导致的晶格弯曲而引起的附加内能和表面能。优良的物理和化学性能使其在纳米新材料中具有广阔的应用前景；高表面活性使其可被用来治理环境污染，但也可对人体造成致命威胁，导致石棉肺并引发癌症。因此，积极开展纤蛇纹石污染和致病机理的深入研究，有针对性的对其进行表面改性，降低或消除其毒性，同时加强采、选及加工企业粉尘污染的监测、改善人员防护，纤蛇纹石可以发挥优良性能，实现物尽其用。  相似文献   

Yellowstone＇s acid waters： A plethora of chemical and biological activity     

D. Kirk Nordstrom 《中国地球化学学报》2006,25(B08):232-233

Yellowstone National Park contains numerous thermal and non-thermal acid waters with pH=1.23-5.0. These acid-sulfate waters are produced from the microbial oxidation of elemental sulfur which is formed from abiotic oxidation of hydrogen sulfide. Metal concentrations are usually very low in these waters so that H^＋ is often the major cation and greater in concentration than Al or Fe.Concentrations of Cu, Zn, Cd, Pb, Co, Ni, and Cr are frequently at or below detection limits. Many of these waters closely approximate pure sulfuric acid solutions. Thermal acid waters have been sampled in Norris Geyser Basin, Gibbon Geyser Basin, Lemonade Creek, and Washburn Springs. Non-thermal acid waters frequently contain high arsenic concentrations. Acid-sulfate waters life： numerous Bacteria, Archaea, and Eukarya. Chemoautotrophs, have been sampled in Brimstone Basin. The thermal acid waters contain an abundance of microbial life from all three domains of phototrophs, and heterotrophs are also common in these waters. Several of these microbes are responsible for the rapid oxidation of iron and arsenic in thermal spring overflows and within large pools. Measured oxidation rates are faster by many orders of magnitude than the abioitic oxidation rates. Common archaea in acid waters include Sulfolobus and Thermoplasma. Common bacteria include Acidithiobacillus, Acidimicrobium, Hydrogenobaculum, and Thiomonas. Common eukarya are algae such as Cyanidium, Euglena, Chlorella, Chlamydomonas, Ulothrix, and Zygogonium. Although aquatic life in acid-sulfate waters is dominated by microbes, insect larvae are also found.  相似文献