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排序方式: 共有217条查询结果,搜索用时 31 毫秒
61.
研究了生物填料滤池对某石化废水产生的臭气的去除效果,并对滤料表面微生物群落结构进行了分析.结果表明,经过一个月左右的驯化,生物滤池对废气污染物的去除逐步提高,稳定阶段对硫化氢、氨氮及挥发性有机酸(VOCs)的平均去除率分别可达98%、91%和90%,并具有较好的抗冲击能力.填料表面生物膜的微生物培养计数表明,生物膜中异养细菌占绝对优势,真菌次之;分离培养得到的菌株中芽孢杆菌属占优势,占随机挑取菌株的62.5%,真菌中青霉属是优势类群.采用DNA单链构象多态性(SSCP)技术分析生物滤料表面微生物群落结构的结果表明,优势微生物种类大多为不可培养细菌,与纯培养分离所得到的微生物类群有很大不同,但优势种属为芽孢杆菌属,与纯培养得到的结果类似均是广泛存在于环境中的臭气污染物去除的主要微生物.滤池内微生物多样性及相似性随运行时间逐渐升高,说明生物填料上的微生物能够利用臭气污染物进行生长,并随运行时间逐渐趋于稳定,微生物群落的变化和系统功能变化相一致. 相似文献
62.
This work describes a new analytical procedure for trace vanadium by graphite furnace atomic absorption spectroscopy coupled
to cloud point extraction (CPE) as the separation-preconcentration method. The CPE behavior of vanadium using methylene blue
as complex agent and Triton X-100 as a surfactant was investigated systematically. Under the optimized conditions, the detection
limit was 0.7 ng · mL−1, and the relative standard deviation was 4.3% for vanadium (c = 50.0 ng · mL−1, n = 5). The recovery of vanadium was in the range of 98.9–102.8%. The method was applied to the analysis of vanadium in certified
reference materials and real samples. The results obtained were in good agreement with the certified values.
Correspondence: Xiashi Zhu, Key Laboratory of Environmental Material and Environmental Engineering of Jiangsu province/College
of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, P.R. China 相似文献
63.
水稻产量要素相关性状QTL定位 总被引:3,自引:0,他引:3
为了定位水稻产量及其要素相关性状QTL并揭示各性状间相关的遗传基础,本研究以来源于杂交组合Lemont/特青的F12重组自交系群体为材料,在大田直播条件下对水稻单株产量、每穗颖花数、每穗实粒数、结实率、千粒重、始穗期、成熟期7个相关性状进行了QTL分析.共检测到22个产量要素相关性状QTL,分布于8条水稻染色体上,单个QTL的贡献率为6%~24%,单个性状QTL位点数为1~5个.共有4个染色体区段的共位点(co-located)QTL能同时影响2~4个产量要素相关性状,并且每个共位点QTL对性状作用的加性效应方向相同,其中2个增效等位基因来自Lemont,另外2个增效等位基因来自特青,这为各性状间表型相关提供了一定的遗传解释. 相似文献
64.
Average life of oxygen vacancies of quartz in sediments is estimated by using the ESR (electron spin resonance) signals of E’ centers from the thermal activation technique. The experimental results show that the second-order kinetics equation is more applicable to the life estimation compared with the first order equation. The average life of oxygen vacancies of quartz from 4895 to 4908 deep sediments in the Tarim Basin is about 1018 a at 27°C. 相似文献
65.
Pan Fusu Zeng Yi Xie Hui Xiong Rui Yu Zuxing Tang Wufeng Shi Jing Mo Shaobo 《化学物理学报(中文版)》2005,18(5):793-797
The core-level X-ray photoelectron emission spectra of the quasi-one dimensional spin 1/2 antiferromagnetic system Sr14-xCaxCu24O41(x=0, 3.5, 6, 7, 8.4) were measured. The main peak of Cu2p3/2 was about 933.8 eV, and the full width of half maximum height was about 3.3 eV. Simulation of Cu2p3/2 by XPSPEAK41 shows that the percents of Cu2+ and Cu3+ in Sr14Cu24O41 are 92.13% and 7.87%, no obvious change to Cu2p core-level is observed by the partial substituting Ca for Sr, and the average valence of Cu in this system is estimated to be 2.08. The main peak of O1s is about 531.0 eV, and the weak shoulder toward the low binding energy direction can be considered as the contribution of Ca-O bond. The binding energies of Ca2p3/2 and Sr3d5/2 indicate that their valence in this system are both +2, without mixed valence. 相似文献
66.
67.
Yu Lu Yudao Ma Shaobo Yang Manyuan Ma Hongju Chu Chun Song 《Tetrahedron: Asymmetry》2013,24(18):1082-1088
Several novel [2.2]paracyclophane-based amino thioureas have been designed and synthesized. The [2.2]paracyclophane-based amino thioureas were used as bifunctional catalysts for organocatalytic enantioselective aldol reactions between ketones and isatins, affording the desired adducts containing a chiral tertiary alcohol in high yields (up to 92% yield) and with good enantioselectivity (up to 88% ee). This is a successful example of employing planar chiral [2.2]paracyclophane-based amino thioureas in asymmetric aldol reactions. 相似文献
68.
Shaobo Lin Feilong Cao Xiangyu Chang Zongben Xu 《Journal of Approximation Theory》2012,164(10):1402-1414
Geodetic and meteorological data, collected via satellites for example, are genuinely scattered and not confined to any special set of points. In order to learn geodetic and meteorological rules, one needs to use these scattered data only to construct an approximant or interpolant. In this paper, we introduce a general distance generated from the scattered data, and, using this, construct a general radial quasi-interpolation operator on the sphere, and we study the convergence rate of this operator. We also show some potential applications of the results obtained here in satellite geodesy. 相似文献
69.
Cai Shaobo Wang Gang Jiang Man Wang Hui 《Journal of Solid State Electrochemistry》2017,21(4):1129-1136
Journal of Solid State Electrochemistry - In this study, we develop a simple template-free strategy to fabricate uniform porous CuCo2O4 hollow spheres. The shells of the as-synthesized CuCo2O4... 相似文献
70.
Yan Wang Kehui Sun Shaobo He Huihai Wang 《The European physical journal. Special topics》2014,223(8):1591-1600
In this paper, dynamical behaviors of the fractional-order sinusoidally forced simplified Lorenz are investigated by employing the time-domain solution algorithm of fractional-order calculus. The system parameters and the fractional derivative orders q are treated as bifurcation parameters. The range of the bifurcation parameters in which the system generates chaos is determined by bifurcation, phase portrait, and Poincaré section, and different bifurcation motions are visualized by virtue of a systematic numerical analysis. We find that the lowest order of this system to yield chaos is 3.903. Based on fractional-order stability theory, synchronization is achieved by using nonlinear feedback control method. Simulation results show the scheme is effective and a chaotic secure communication scheme is present based on this synchronization. 相似文献