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291.
多氯代二苯并-对-二噁的微生物降解 总被引:6,自引:0,他引:6
从多氯代二苯并-对-二噁(PCDDs)污染的土壤和含氧沉积物中分离筛选出8株降解PCDDs的菌株,均能以一氯代和二氯代二为单一碳源和能源生长并使其降解,多数几乎不能降解三氯代二噁.但是,用邻二氯苯作为初级营养共代谢物,可以增强菌株对较高氯代二噁(如三氯代和四氯代二噁)的降解能力.利用所筛选菌株中的1株,经鉴定为假单胞菌EE41(Pseudomonas sp.EE41).降解试验结果表明,1,2,3-TrCDD在浓度为1.2mg/L时3周内可降解33%,2,3,7,8-TCDD在0.1 mg/L时3周内最多可降解37.8%.试验的高氯代二噁(pCDD,H6-CDD,H7-CDD和OCDD)则只被菌体强烈吸收并积累,却不能被降解. 相似文献
292.
Occupational Safety and Health in Finland 总被引:1,自引:0,他引:1
In Finland, occupational safety is the responsibility of the employer, while the occupational safety and health laws are enforced by the Labour Inspection Service, an organization of the state. The Labour Inspection is divided in 11 administrative districts, and it employs 360 professionals. They are mandated to carry out site visits without prearranged appointments to inspect safe work situations, working hours, construction safety, or any aspect of accident risks. The inspectors are also mandated to verify the existence of sufficient occupational health services as prescribed by the Occupational Health Services Act for all employees. The occupational health services are typically provided by enterprise-owned medical departments, by mutually owned health care centers, by private practitioners, or by municipal health care centers. The latter are required by law to provide all services as prescribed by the legislation to anyone who comes to the facility. This situation is prevalent in the countryside, where there are very few private caregiving centers. Declaring occupational accidents and disease cases is mandatory, and the Inspection districts examine all accidents to establish causes and consequences, and to initiate prosecution in case of criminal negligence. Labour Inspection Districts are also notified of the new occupational disease cases as they are declared to insurance companies. Insurance for occupational disease, accidents, and death is an obligation of the employer, although they can choose the insurance company. The medical confidentiality between the workers and their occupational health care providers is very strict. Official statistics are maintained by the state Statistics Finland organization, and they may be used, for example, for research purposes by scientific institutes like the Finnish Institute of Occupational Health. Construction industry accounts for 25% of all fatal accidents (120 cases per 1 million working hours), followed by mechanical, wood, metal, machinery, and pulp and paper industry (10% each of fatal accidents) with rates ranging from 100–160 cases per 1 million working hours. There are some 5,000 occupational disease cases per year (rate 22/10,000 employed). The major disease categories include repetitive strain injuries (1,300 cases), respiratory allergies (600 cases), occupational skin diseases (1,000 cases), and 900 cases of noise-caused hearing loss. In 1998, 589 cases of asbestos-related diseases were reported. 相似文献
293.
皂素工业废水CODCr排放限值的研究 总被引:1,自引:1,他引:0
皂素工业是近几年来迅速发展的一个重要生物医药化工行业,我国皂素主产区位于南水北调中线工程水源汉江上游,其排放的大量高浓度含酸有机废水给水源保护带来严重威胁,急需制定我国的皂素工业水污染物排放标准.采用三段式两相厌氧为核心的二级生化组合工艺技术从实验室试验、现场工业性试验和示范工程三方面对皂素工业废水CODCr排放限值进行了研究,皂素废水二级生化处理出水中残留CODCr总量(以质量浓度计)约为400~500 mg/L,其中溶解性微生物代谢产物(SMP)质量浓度约为240~280 mg/L.综合考虑技术可达性和经济可行性,将现有企业CODCr排放限值规定为400 mg/L;为引导企业对废液综合利用,推进皂素行业清洁生产,规定新建企业和现有企业的第二时段的限值为300 mg/L.提出了丹江库区相应的CODCr总量指标及皂素规模限额.执行该标准后,全国每年可削减CODCr 71 400 t,其中南水北调中线工程水源汉江上游至少可削减60 690 t,可以满足中线调水水源区的环境保护要求. 相似文献
294.
295.
Ram Kailash P. Yadav Efimia M. Papatheodorou Katerina Karamanoli Helen-Isis A. Constantinidou Despoina Vokou 《Chemoecology》2008,18(4):217-226
Summary. We studied the epiphytic bacterial communities of the summer leaves of eight perennial species naturally occurring in a Mediterranean
ecosystem. The species differ in essential-oil content (from rich in essential oil to non-producers) and composition, and
also in life form (from herbaceous species to tall shrubs). We compared the epiphytic bacterial communities on the basis of
(i) their abundance, (ii) their metabolic profile (derived by use of the BIOLOG Ecoplate system) and (iii) richness and diversity
of substrates that they use, as a measure of functional diversity. Among all species, the aromatic Melissa officinalis was the most abundantly colonized. The bacterial communities on the leaves of the aromatic Myrtus communis, Calamintha nepeta and Melissa officinalis, and also of Cistus incanus catabolized all 31 substrates offered; those on the evergreen-sclerophyllous species, Arbutus unedo and Quercus coccifera, catabolized only 14 and 17 substrates, respectively. Carbohydrates were consistently used abundantly by all communities,
whereas carboxylic acids were most variably used. On average, the group of aromatic plants scored higher regarding bacterial
abundance, and richness and diversity of substrates used by the bacterial communities on their leaves; the lowest values for
both substrate-use indices were recorded in A. unedo. Bacterial abundance or richness or diversity of substrates used did not vary with leaf oil content. Abundance was positively
correlated with both substrate-use indices. Results support claims that the antimicrobial effects of essential oils are not
exerted so much under natural conditions as reports based on biassays with pathogens usually show. Although essential oils
play a part in the microbial colonization of the phyllosphere, it is not likely that inhibition of phyllosphere bacteria is
essential oils’ primary role, at least in the Mediterranean environment. 相似文献
296.
不同环境条件下偶氮染料酸性大红GR的生物降解性能 总被引:1,自引:0,他引:1
为了考察不同环境条件下偶氮染料酸性大红GR生物降解性能,采用已驯化的混合菌群作为接种液进行偶氮染料酸性大红GR脱色试验。结果表明,微氧条件下(静置敞口培养),偶氮染料酸性大红GR脱色效果最佳,染料脱色主要发生在菌体的对数生长期。混合菌群对pH、温度适应范围较广,pH为3.32~9.18,温度在20℃~37℃范围内均可以获得较好脱色效果,脱色率均在80%以上。微氧条件下酸性大红GR降解历程表明,偶氮基整个共轭系统被破坏,生成了一种新的结构,使原有的某些精细结构在二阶导数光谱中得以表现,由此探讨其生物降解机理。 相似文献
297.
对武汉东湖3个采样点柱状沉积物中总氮、总磷、总有机碳及微生物量的垂向分布进行了测定,并对生源要素与微生物量之间垂向分布的相关性进行了研究.结果表明,东湖柱状沉积物中总有机碳与总氮之间存在明显的同步变化趋势,其含量随着沉积物深度的增加而不断降低,处于纳污区的1号点的各种营养盐含量均显著高于其它各点.沉积物中的有机质有着明显的双重来源,1号点含有较高的陆源有机质成分,而远离排污口部分的2号和3号点的有机质来源则以水生生物为主.微生物量在沉积物表层最高,随着沉积物深度的增加而不断下降.微生物量与有机质含量之间存在极显著的相关性,但是受有机质来源不同的影响,微生物量与总氮、总磷之间仅在远离排污口部分存在极显著相关性. 相似文献
298.
Changes in soil microbial community structure associated with two types of genetically engineered plants analyzing by PLFA 总被引:3,自引:0,他引:3
With the rapid expansion of GEPs(genetically engineered plants), people are more and more concerned about the ecological risks brought by their release. Assessing the effect of GEPs on soil microbial ecology is indispensable to study their ecological risks. In our study, the phospholipids fatty acid(PLFA) method was used to analyze the microbial community of soil samples collected from fields with two types of GEPs-Bt transgenic com and PVY( potato virus Y) cell protein gene transgenic potato. The principal components analysis(PCA) showed all controls were on the right of related GEPs samples along the PC1 (the first principal component) axis, which means a decrease of fungi in soils with genetically engineered crop since most of PLFAs that are strongly positively correlated with PC1 represent fungi. For samples collected from Bt transgenic cornfield, the ratios of gram-positive to gram-negative bacteria were less than those of controls. For samples of transgenic potato field, these ratios were lower than those of controls when soils were collected from deep layer(20-40 cm), but were higher when soils collected from surface layer(0-20 cm). For soils collected from 0-20 cm, the ratios of fungi to bacteria for all GEPs samples were at the same level. So were such rations for all controls. Changes of soil microbial community in two types of GEPs fields were detected in our study, but the causes and more information still needs further study. 相似文献
299.
300.
生物还原-化学沉淀去除烟气SO2中Na2 SO3和硫化物的研究 总被引:1,自引:0,他引:1
利用硫酸盐还原菌(SRB)和金属离子沉淀剂对烟气SO2进行生物还原-化学沉淀去除,考察了碳源类型、乙酸(碳源)浓度、沉淀剂投加量和反应时间对SO3^2-去除的影响,研究表明,沉淀剂的加入导致SRB转化产生的S^2-能很快生成硫化物沉淀,其它副反应被抑制.乙酸C原子/SO3^2-的浓度比为1时,SO3^2-去除最大.随着沉淀剂投加量的增加,SO3^2-去除率增大.ZnCl2生化反应培养14d后,SO3^2-去除趋于完全.FeCl2生化反应培养7d后,SO3^2-去除趋于完全. 相似文献