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971.
从本公司生物曝气池中筛选分离到了5株能高效降解对苯二甲酸(PTA)的菌株,编号为T1,T3,T5,T6,T7.利用16S rDNA测序后进行序列比对分析结果表明其分别为不动杆菌(Acinetobacter sp),不动杆菌(Acinetobacter sp),松鼠葡萄球菌(Staphylococcus sciuri),松鼠葡萄球菌(Staphylococcus sciuri),恶臭假单胞菌(Pseudomonas putida).在30度,pH7.5,1%接种量的条件下,培养72 h,PTA的降解率可达97%以上.对实际的印染废水中的PTA也有较好的降解效果,培养48 h后降解率最高可达65.6%.其中T1,T3有一定的实际应用价值.  相似文献   
972.
To understand the short-term effects of forest gap by human harvesting on soil available nutrient in Pinus massoniana plantations, the variations of soil ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3-N) concentrations in the gap center and gap edge during growing season were observed in seven gaps of different size (Gl: 100 m2; G2:225 m2; G3:400 m2; G4:625 m2; G5:900 m2; G6:1225 m2; G7:1600 m2) and pure understory of a 39-year-old masson pine plantation in a hilly area of the upper reaches of Yangtze River. The results showed that in the early stage of gap formation, the gap size had significant effect on NH4+-N, the season changes on NP3--N, and the interaction effect of gap size and seasonal variation on NH4+-N and NO3--N. The difference of NH4+-N and NO3--N between the gap center and gap edge was not significant. (I) The NH4+-N content was 4.30-11.99 mg kg-1, and NO3--N content was 2.57-10.81 mg kg-1. There was no obvious difference in NH4+-N and N03--N among gaps of different size in early or late growing seasons, when both increased first and decreased afterwards in the middle of growing season. The gaps of 100∼400 m2 area had a higher content of available nitrogen. (2) The seasonal dynamic differed between NH4+-N and NO3--N, with the former lower in middle growing season whereas the latter higher in the middle growing season but lower in the end of growing season. The soil NH4+-N was higher than NO3- -N in the early and late periods, but lower in the middle period. (3) The soil NH4+-N and NO3--N in parts of gaps were lower than understory in the early and late growing season. (4) Correlation analyses showed that NH4+-N had significant positive correlation with microbial biomass nitrogen (MBN), and NO3--N with soil temperature, MBN and organic matter. But the impact of soil water content on available nitrogen was not significant. These results suggested that soil temperature and microbial activity variation caused by gap harvesting are the main factors affecting soil available nitrogen content of Pinus massoniana plantations.  相似文献   
973.
Emotional labor (expressing emotions as part of one's job duties, as in “service with a smile”) can be beneficial for employees, organizations, and customers. Meta‐analytical summaries reveal that deep acting (summoning up the appropriate feelings one wants to display) generally has positive outcomes. Unlike surface acting (faking emotions), deep acting does not harm employee well‐being, and deep acting is positively related with job satisfaction, organizational commitment, job performance, and customer satisfaction. Emerging research also suggests that a third form of emotional labor, natural and genuine emotional labor, is a frequently used emotional labor strategy that has positive effects for both employees and customers. We examine how identity processes shape how employees experience emotional labor, and we maintain that when employees identify with their roles, emotional labor augments and affirms their identity. Person‐job fit is an important moderator that influences whether emotional labor enhances or hinders employee well‐being. Emotional labor may also have positive outcomes when organizations grant more autonomy and adopt positive display rules that call for the expression of positive emotions. Recent research also indicates that emotional labor strategies may improve leadership effectiveness. Research opportunities on the bright side of emotional labor are abundant. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
974.
露天矿山运输系统事故原因涉及人、机、环、管等多个环节。基于运输系统复杂、高事故率这一实际情况,以人为因素作为风险因素的分析中心,在总结传统人为风险因素辨识模型存在不足的基础上,提出基于工作分解结构(WBS)与R-SHEL相结合的风险因素辨识模型。将模型具体应用在国内某大型铝土矿山运输系统风险因素研究中,确定5个一级因素指标、13个二级因素指标及40个三级因素指标,采用三级标度IAHP与模糊(fuzzy)相结合的方法实现指标体系中风险因素的综合评判,得出综合评判结果与现场实际情况基本相符。  相似文献   
975.
本文提出将聚类算法引入到ERT监测系统中,采用K均值(K-means)聚类、模糊C均值算法(FCM)以及混合高斯模型(GMM)3种常用聚类算法对ERT检测结果进行污染区域识别,通过一个数值模型分析了3种算法的识别效果.研究结果表明当污染区域与背景土壤的电阻率区分度较大时(电阻率差异性大于30%),采用3种聚类算法都可以识别出污染区域,K-means和FCM的识别效果优于GMM算法.最后,给出一个实际场地调查的应用案例.  相似文献   
976.
Measurements of low-level radioactivity often give results of the order of the detection limit. For many applications, interest is not only in estimating activity concentrations of a single radioactive isotope, but focuses on multi-isotope analyses, which often enable inference on the source of the activity detected (e.g. from activity ratios). Obviously, such conclusions become questionable if the measurement merely gives a detection limit for a specific isotope. This is particularly relevant if the presence of an isotope, which shows a low signal only (e.g. due to a short half-life or a small transition probability), is crucial for gaining the information of interest.  相似文献   
977.
邻苯二甲酸二丁酯的酶促降解性的研究   总被引:3,自引:0,他引:3  
测定了Pseudomonas fluorescens FS1的邻苯二甲酸酯降解酶对邻苯二甲酸二丁酯的降解特性;提出了邻苯二甲酸二丁酯酶促降解的途径,Pseudomonas fluorescens FS1细胞中的颗粒部分、溶液部分对邻苯二甲酸二丁酯都具有降解作用,Pseudomonas fluorescens FS1的邻苯二甲酸酯降解酶尾胞内酶;Pseudomonas fluorescens FS1  相似文献   
978.
玉米种子的DNA指纹计算机化鉴定   总被引:11,自引:0,他引:11  
对12个优良玉米自效系的DNA进行了RAPD分析,共筛选了250个Operon引物,其中12个引物共扩增出59个多态性产物,根据这59个多态性RAPD产物,对12个自交系进行了聚类分析,把它们分为3个群,结果与根据系谱法的聚类结果一致。经过优选,用OPN-11扩增出的11种DNA带,建立了这12个自交系的RAPD-DNA指纹图谱。在该图谱呼弱个自交系都具有特异的DNA指纹,可以与其它自效纱相区别。  相似文献   
979.
土地利用规划的生态满意度评价与环境影响分析   总被引:1,自引:0,他引:1  
摘 要: 土地利用总体规划的环境影响包括对传统环境影响评价要素的影响及对区域人-地系统的影响。土地利用总体规划中的刚性方案与弹性方案的环境影响有着不同的表现形式,它们使得土地利用规划的环境影响评价变得更为复杂。鉴于土地利用总体规划这一环境影响评价对象的特殊性,提出了土地利用总体规划环境影响分析与生态满意度评价的方法。根据仙桃市土地利用总体规划方案,识别了各种污染源。在MAPGIS支持下进行了面域分析与空间统计处理,预测了规划实施后主要环境指标的变化;根据预测的规划实施后的生态指标变化,进行生态满意度评价。结果表明:规划区预测生态满意度值为7485,生态环境总体处于良好水平,但水污染还比较严重,应该加强治理,固体废物无害化处理也应该得到重视。土地利用总体规划环境影响评价存在着诸多不确定性,评价过程中应根据规划内容与区域差异选择合适的指标建构生态满意度评价体系。  相似文献   
980.
一株高效脱硫菌的分离鉴定和脱硫特性研究   总被引:3,自引:0,他引:3  
从污水净化厂二沉池回流污泥中分离到一株硫杆菌菌株dj-5,该菌株是一种兼性厌氧菌,通过生理生化特性鉴定,并结合16S rDNA序列分析及鉴定,该菌株可以确定为脱氮硫杆菌(Thiobacillus denitrificans)。该菌株的生长曲线表明菌体生长迅速,延滞期约为8 h,然后细菌进入对数生长期,这一阶段持续时间大约20~24 h,稳定期较短,细菌很快进入衰亡期。通过脱硫工艺实验考察了pH值、温度和搅拌速度对脱硫率和菌体生长的影响,结果表明,在进气量180 L/h、pH=6~8、温度为25~35℃和搅拌速度为270 r/min时,该菌株能正常生长,对进气浓度高达2 500 mg/m3的硫化氢脱除率在91%以上。  相似文献   
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