不同EPS组成生物膜对Cu2+吸附的研究

采用自行设计的反应器,通过调节培养液的配比对载体进行挂膜,得到蛋白质和多糖含量比分别为7:1、5:1和10:1的3种生物膜作为吸附剂,用其对Cu2+进行吸附试验,同时对吸附机理进行探讨.结果表明,培养8d后,生物膜可挂膜成熟,在C/N=12时,生物膜上的菌落数较C/N=4和C/N=37条件下多.PN/PS值越小,生物膜对铜的吸附量越高,EPS3对Cu2+的吸附量分别高出EPS1 7.37 %, EPS2 7.62%.在生物膜吸附Cu2+后,溶液中Ca2+、Mg2+、K+含量明显升高,表明离子交换对生物膜吸附Cu2+起主要作用,且Cu2+更易与Ca2+和Mg2+产生离子交换作用.当KNO3浓度在0.1~0.6mol/L之间,随着离子强度的增加,生物膜吸附Cu2+的量迅速减少,当KNO3浓度大于0.6mol/L时,生物膜对Cu2+吸附量的变化趋于平缓,说明生物膜对Cu2+的吸附同时包括离子交换吸附和化学吸附.     

板坯火焰清理机烟气治理技术

介绍了国产板坯火焰清理机烟气的治理系统及湿式电除尘器的结构和技术特点.结果表明,该烟气治理系统及湿式电除尘器能够满足火焰清理机工况和烟气排放的环保要求,完全可以替代同类进口设备.     

工业废水对洹河有机污染的调查与分析

采用适当的样品前处理技术,利用GC/MS对洹河水及焦化厂、染料厂废水进行有机污染物的分析,确定了工业废水对洹河造成有机污染的主要化合物,从而为企业污水的处理和洹河治理提供依据.     

Low-temperature CO oxidation over Au-doped 13X-type zeolite catalysts: preparation and catalytic activity

Au-supported 13X-type zeolite (Au/13X) was synthesized using a common deposition–precipitation (DP) method with a solution of sodium carbonate as a precipitate agent. Further testing was conducted to test for catalytic oxidation of CO. A study was conducted on the effects of different preparation conditions (i.e., chloroauric acid concentration, solution temperature, pH of solution, and calcinations temperature) on Au/13X for CO oxidation. In respect to the catalytic activity, the relationship between different the preparation conditions and gold particles in 13X zeolite was analyzed using X-ray diffraction, TEM and XPS. The activity of Au/13X catalysts in CO oxidation was dependent on the chloroauric acid concentration. From XRD results, a higher chloroauric acid concentration induced larger gold nanoparticles, which resulted in lower catalytic activity. Results revealed that higher temperatures induced higher Au loading, homogeneous deposit, and smaller gold clusters on the support of 13X, resulting in higher CO activity. Furthermore, a pH of 5 or 6 generated greater amounts of Au loading and smaller Au particles on 13X than at a pH of 8 or 9. This may be a result of an effective exchange between Au(OH)2Cl2- and Au(OH)₃Cl^- on specific surface sites of zeolite under the pH’s 5 and 6. The sample calcined at 300°C showed the highest activity, which may be due to the sample’s calcined at 200°C inability to decompose completely to metallic gold while the sample calcined at 400°C had larger particles of gold deposited on the support. It can be concluded from this study that Au/13X prepared from a gold solution with an initial chloroauric acid solution concentration of 1.5 × 10^-3 mol·L^-1 gold solution pH of 6, solution temperature of around 90°C, and a calcination temperature of 300°C provides optimum catalytic activity for CO oxidation.     

Essential and nonessential elements in the red-crowned crane Grus japonensis of Zhalong Wetland,northeastern China

The concentrations of four essential (Ca, Mg, Zn, and Cu) and two nonessential elements (Pb and Cd) in feathers and kidneys, livers, gut walls, and muscles of eight carcasses of migratory red-crowned cranes (Grus japonensis) from Zhalong Wetland, northeastern China, were examined. The concentrations of Cd in the feathers were between 0.4 mg kg^?1 dry weight (dw) and 3.1 mg kg^?1 dw, in the livers between 0.4 and 4.4 mg kg^?1 dw, the maximum of which exceeded a level considered to be environmental exposure risk (i.e., 3 mg kg^?1 dw in the liver or kidney). High Pb levels (0.4–3.2 mg kg^?1 dw, with an average of 1.8 mg kg^?1) were also detected in livers, which exceeded a level considered toxicosis in birds (1.7 mg kg^?1 dw). Pb and Cd had the highest scores in principal component analysis. Relatively high Pb and Cd concentrations in the migratory cranes were thought to be associated with their habitat and prey.     

基于FTA的尿素热解脱硝系统可靠性分析

为提高尿素热解脱硝系统可靠性水平,通过分析系统组成和各种可能的失效情况,以尿素热解脱硝系统不能正常工作为顶事件建立了故障树,对其进行定性分析,求取了故障树的最小割集。同时在此基础上分析了各个基本事件的结构重要度,明确了导致尿素热解脱硝系统失效的主要影响因素,并对其相应的解决措施进行了探讨。     

Dynamic changes in radial oxygen loss and iron plaque formation and their effects on Cd and As accumulation in rice (Oryza sativa L.)

Temporal variations and correlations between radial oxygen loss (ROL), iron (Fe) plaque formation, cadmium (Cd) and arsenic (As) accumulation were investigated in two rice cultivars at four different growth stages based upon soil pot and deoxygenated solution experiments. The results showed that there were significant differences in ROL (1.1–16 μmol O₂ plant^?1 h^?1), Fe plaque formation (4,097–36,056 mg kg^?1), Cd and As in root tissues (Cd 77–162 mg kg^?1; As 49–199 mg kg^?1) and Fe plaque (Cd 0.4–24 mg kg^?1; As 185–1,396 mg kg^?1) between these growth stages. ROL and Fe plaque increased dramatically from tillering to ear emergence stages and then were much reduced at the grain-filling stage. Furthermore, significantly positive correlations were detected between ROL and concentrations of Fe, Cd and As in Fe plaque. Our study indicates that increased Fe plaque forms on rice roots at the ear emergence stage due to the increased ROL. This stage could therefore be an important period to limit the transfer and distribution of Cd and As in rice plants when growing in soils contaminated with these toxic elements.     

利用改进的SOS/umu方法检测水处理过程中污染物的遗传毒性效应

SOS/umu遗传毒性测试方法被广泛应用于化合物和复杂混合物遗传毒性的评价,但是目前已报道方法的实验周期长达17 h,给实验操作带来了不便,因此亟需对常规方法进行改进。建立了测试周期可小于8 h(2 h预培养,4.5 h暴露培养) 的SOS/umu快速测定方法之后,应用改进后的方法对5种典型遗传毒性物质, 4-硝基喹啉1-氧化物(4-NQO)、丝裂霉素C(MMC)、甲磺酸甲酯(MMS)、2-氨基蒽(2-AA)和苯并芘(BaP)进行测定,结果表明,改进后的SOS/umu方法对4-NQO、MMC、MMS、2-AA和BaP的检测限分别为0.013±0.0031、0.031±0.0028、229.18±60.51、2.29±1.22和1.28±0.0698 μmol·L^-1,优于或者相当于报道方法。采用经典方法和改进后的方法对全国两个地区6个环境水样的遗传毒性进行测定,结果表明,两种方法检测出的6个环境水样的遗传毒性强度无显著性差异。另外,将研究方法应用于北方某市甲乙两个水厂原水、出厂水和管网水的遗传毒性评价,结果表明,两个水厂的原水、出厂水和管网水均表现出一定的直接遗传毒性,对应的4-NQO当量浓度(TEQ4-NQO)在0.0012 μg·L^-1至0.0129 μg·L^-1之间;加入鼠肝微粒体酶系统(S9)后,仅有乙水厂的管网水检测出极其微弱的遗传毒性效应。以上研究结果表明,改进后的SOS/umu快速测定方法能够实现在短时间（8h）内完成环境化合物及环境样品的遗传毒性检测,为筛选和评价化合物和复杂环境样品的遗传毒性提供了更为快捷的手段。     

Degradation of bisphenol A by microorganisms immobilized on polyvinyl alcohol microspheres

In this study, microorganisms （named B111） were immobilized on polyvinyl alcohol microspheres prepared by the inverse suspension crosslinked method. The biodegradation of bisphenol A （BPA） and 4-hydro- xybenzaldehyde, a degradation product of BPA, by free and immobilized B lll was investigated. The BPA degradation studies were carried out at initial BPA concentrations ranging from 25 to 150 mg·L^-1. The affinity constant Ks and maximum degradation rate Rmax were 98.3 mg·L^-1 and 19.7mg·mg^-1VSS·d^-1 for free B111, as well as 87.2mg·L^-1 and 21.1mg·mg^-1VSS·d^-1 for immobilized B 111, respectively. 16S rDNA gene sequence analyses confirmed that the dominant genera were Pseudomonas and Brevundimonas for BPA biodegradation in microorganisms B 111.     

Co对腈纶废水厌氧处理效果的影响

利用厌氧反应装置,以腈纶废水为处理对象,通过2组试验,对比了微量金属(Co)投加前后废水中有机物降解情况、累积产气量、三维荧光光谱图以及微生物生长情况,研究了微量Co对腈纶废水厌氧处理效果的影响.结果表明:当Co的投加浓度〔以ρ(CoCl2)计〕为1.0 mg/L时,CODCr去除率达71.7%,累积产气量达到22.5 mL;当Co的投加浓度超过10 mg/L时,CODCr去除率为20%左右,累积产气量8.5 mL,未投加Co元素的空白对照组CODCr去除率为43.1%,累积产气量为10 mL.显示微量Co对腈纶废水厌氧生物降解具有一定的促进作用.