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51.
电除尘器气流分布试验研究和数值计算   总被引:1,自引:1,他引:0  
结合660 WM机组电除尘器的设计要求,对电除尘器内气流流动进行了数值模拟与试验研究.计算中选择SIMPLE方法求解三维雷诺平均方程和κ-ε两方程湍流模型.研究结果表明,无论电除尘器两室流量分配还是第一电场进口断面气流分布,计算结果与试验吻合较好,数值计算结果可以指导电除尘器设计与模型试验研究.  相似文献   
52.
污泥果肥利用中重金属迁移特征研究   总被引:1,自引:0,他引:1  
为了厦门城市污泥的安全利用,将石渭头污水处理厂污泥经过好氧堆肥后施用于柚子树,对重金属元素在土壤、树叶及果肉中的迁移特征进行了研究。结果表明:Cd在土壤中的富集能力强;重金属元素从土壤向树叶迁移累积能力比向果肉的大得多,污泥肥料不能用于叶类食用植物的施用;Cr向树叶、Ni向果肉的迁移累积能力强;泥肥的施用加重了土壤中Cd的污染,提高了Cr向树叶、Ni向果肉的迁移能力;污泥果肥利用需降低Ni的浓度,对污泥中含量较高的Cu、Zn、Ni、Cr和Cd需进行跟踪检测。  相似文献   
53.
林业生物灾害的监测调查技术研究进展   总被引:1,自引:1,他引:0  
介绍了航天遥感、航空遥感、地面调查等技术在林业生物灾害监测中的应用现状与发展历程,在分析上述三项技术优缺点的基础上,提出了在我国建立树木、林分、景观等尺度综合监测技术体系,开展林业生物灾害监测与调查的方法及相关建议.  相似文献   
54.
地震现场数据共享标准化研究及其标准起草   总被引:5,自引:0,他引:5  
标准化被普遍认为是保证信息更有效处理、交换、管理以及消除技术壁垒的最有效手段.信息共享标准是为规范信息共享的行为而制订的,是实现信息共享的"软"环境.通过对地震现场信息共享标准化研究,概述了这一标准制定的过程、总体内容框架安排的一些考虑以及存在问题,讨论了地震现场信息共享标准分类与编码体系、数据交换格式、元数据、数据字典及数据质量控制等与信息共享标准相关的一些问题.  相似文献   
55.
Zhang C  Zeng G  Yuan L  Yu J  Li J  Huang G  Xi B  Liu H 《Chemosphere》2007,68(1):181-190
A novel bacterium designated strain B-16 was isolated from the compost leachate of the municipal solid waste (MSW) in a laboratory reactor. This strain was identified as a gram-negative bacterium, Achromobacter xylosoxidans that could grow on bisphenol A (BPA, a representative endocrine disruptor) as a sole carbon source under aerobic condition. BPA-degrading characteristics of strain B-16 were investigated in liquid cultures. The results show that BPA degradation was influenced by several factors (e.g. inoculum size, substrate concentration, temperature and pH, etc). The half-lives, optimum temperature and pH were found to be 0.58-3.1d, 35 degrees C and 7.0, respectively. BPA-degrading activity and cell growth were inhibited at high substrate concentration. Metabolic intermediates detected during the degradation process were identified as p-hydroxybenzaldehyde, p-hydroxybenzoic acid and p-hydroquinone, respectively. Metabolic pathway of BPA degradation was proposed in this study.  相似文献   
56.
Fu F  Zeng H  Cai Q  Qiu R  Yu J  Xiong Y 《Chemosphere》2007,69(11):1783-1789
A new dithiocarbamate-type heavy metal precipitant, sodium 1,3,5-hexahydrotriazinedithiocarbamate (HTDC), was prepared and used to remove coordinated copper from wastewater. In the reported dithiocarbamate-type precipitants, HTDC possesses the highest percentage of the effective functional groups. It could effectively precipitate copper to less than 0.5 mg l−1 from both synthetic and actual industrial wastewater containing CuEDTA in the range of pH 3–9. UV–vis spectral investigation and elemental analysis suggested that the precipitate was a kind of coordination supramolecular compound, [Cu3(HTDC)2]n. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) indicated that the supramolecular precipitate was non-hazardous and stable in weak acid and alkaline conditions. Tests of an anion exchange resin D231 provided a clue to simultaneously remove excess HTDC and residual CuEDTA in practical process of wastewater treatment.  相似文献   
57.
Chen D  Zeng X  Sheng Y  Bi X  Gui H  Sheng G  Fu J 《Chemosphere》2007,66(2):252-258
Polycyclic musks [cashmeran (DPMI), celestolide (ADBI), phantolide (AHMI), traseolide (ATII), tonalide (AHTN) and galaxolide (HHCB)] in the air, wastewater, sludge samples of a typical cosmetic plant were analyzed. DPMI, ADBI, HHCB and AHTN were found in all samples, and ATII was not found in any sample. HHCB and AHTN were the major components in all samples. The polycyclic musk concentrations were very high in the air of the cosmetic plant, and polycyclic musks were mostly contained in the gas phase at the percentage of 86.35-97.70%. Average polycyclic musk concentrations in effluent were high, and ranged from 0.62 to 32.06 microgl-1. The removal efficiency during the active sludge wastewater treatment was also high, resulting from the adsorption of those compounds into the sludge. So the polycyclic musk concentrations were very high in the primary sludge and second sludge, and ranged from 1.78 to 92.45 mgkg-1 (dry), and from 2.87 to 65.67 mgkg-1 (dry), respectively. Results suggested that the sludge needed to be further treated to make polycyclic musks less influence to the environment.  相似文献   
58.
在选择最佳测定条件的基础上,对比了模拟酶蛋白结合物和HEMIN对过氧化物的测定效果。结果表明,HEMIN-BSA效果最好,其对过氧化物的荧光响应信号约是HEMIN的2倍,该物质在不改变激发和发射光谱的前提下可增强反应活性,提高反应灵敏度,使方法检测限降低至使用HEMIN时的1/3左右,最低线性值降至原来的1/5左右,同时,精度亦有所提高。  相似文献   
59.
离子色谱法测定大气中的甲磺酸   总被引:7,自引:0,他引:7  
胡敏  陆昀  曾立民 《环境化学》2000,19(6):572-576
建立了以玻璃纤维膜-KB120气溶胶采样器采集大气中甲磺酸的采样方法;以0.1mmol·l-1H3BO3/0.1mmol·l-1 Na2B4O7为淋洗液的甲磺酸离子色谱分析方法.分析方法的精密度和准确度分别为5%和4%.并实测了青岛冬季大气气溶胶中MSA,SO2-4和NO-3的平均浓度分别为0.10μg·m-3,30.40μg·m -3和17.98μg·m-3.  相似文献   
60.
Analysis of satellite-telemetry data mostly occurs long after it has been collected, due to the time and effort needed to collate and interpret such material. Delayed reporting reduces the usefulness of such data for nature conservation where timely information about animal movements is required. To counter this problem, we present a novel approach which combines automated analysis of satellite-telemetry data with rapid communication of insights derived from such data. A relatively simple algorithm (based on radial and angular velocity calculated from fixes) allowed instantaneous detection of excursions away from settlement areas and automated calculation of home ranges on the remaining data. Automating the detection of both excursions and home-range calculations enabled us to disseminate ecological insights from satellite-tag data instantaneously through a dedicated web portal. The automated analysis, interpretation, and communication of satellite-tag and other ecological data offer clear benefits to nature conservation research and practice.  相似文献   
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