再生聚丙烯的洁净化和高质化应用

聚丙烯以其优异的机械性能、高的性价比和多重改性方式成为重要的通用树脂之一,这些产品废弃后产生了种类繁多和数量巨大的再生聚丙烯.通过将再生聚丙烯根据性能和来源进行分类,然后分类阐述各再生聚丙烯物料特点,结合再生聚丙烯改性方式,为高质化应用提出方向.     

崇明东滩湿地沉积物重金属污染的磁诊断

对取自崇明东滩的高潮滩、中潮滩和低潮滩的沉积物柱样进行了磁学、粒度、重金属含量等指标的分析、比较与综合研究. 结果表明:在以粉砂为主的崇明东滩,通过污染负荷指数法进行评价,除低潮滩无污染外,中潮滩和高潮滩均有中度的重金属污染. 选取中度重金属污染的高潮滩沉积物柱样进行粒度、重金属含量以及磁性参数的相关性分析显示,χ_fd,χ_ARM/SIRM与重金属含量和粘土(粒径<4 μm)之间有较高的相关性,并以此建立了磁诊断线性回归模型;χ_fd和χ_ARM/SIRM可作为重金属含量的替代指标.      

对羟基苯甘氨酸生产废水的处理工艺研究

对羟基苯甘氨酸废水属于高浓度难处理有机废水,针对生产工艺的特点,采取了废水分类处理的新路线.试验结果表明,高浓度废水经过物化处理后,苯酚的回收率达到95%,每日回收硫酸铵约6t;低浓度废水采取水解酸化-接触氧化-沉淀-活性炭吸附工艺是可行的,COD、BOD5、NH3-N及挥发酚的总去除率分别为95.6%、94.6%、93.7%和99%.     

好氧-缺氧一体化高效分离生物流化复合反应器

鉴于污水处理中对氮、磷去除率的要求和内循环三相生物流化床反应器存在的一些不足,为此,设计开发了一种好氧-缺氧一体化高效分离生物流化复合反应器。该反应器对好氧循环流化区采用了独特的分格结构,当反应器处理规模增大时,在不增加反应器总体高度的基础上,保证了循环流化区的高径比。循环流化反应器与高效气浮分离反应器的耦合,克服了循环流化床以沉淀原理为基础的固液分离效果不佳的状况,既可以保证出水水质,又可以实现反应器的一体化。通过气体提升方式实现了好氧出水回流,使该种反应器能够实现脱氮和部分除磷的目的。该反应器处理生活污水的初步试验结果表明它具有很好的抗冲击负荷和去除有机物的性能。     

复合式膜生物反应器处理高浓度氨氮废水可行性试验

试验结果表明,以甲壳素为载体的复合式膜生物反应器,在进水氨氮浓度为2100mg/L,氨氮容积负荷为2.19kg/(m3.d)时,氨氮去除率接近100%,系统运行稳定。载体投加量为2.778g/L时,膜通量可维持在87%左右。     

新型单级A/O程序无回流复合膜生物反应器处理氨氮废水的试验

采用单级A/O程序复合膜生物反应器(HSMBR)处理高氨氮废水,研究在低DO浓度下系统对有机物、氨氮和总氮的去除效率。研究结果表明:在低DO浓度下,CODCr、氨氮的平均去除率分别为94.4%和92.8%。由于进水CODCr/TN值仅为2.01,则使得总氮平均去除率仅为69.4%,但是当系统亚硝化累积率从60.5%～67.1%提高到83.5%～86.4%时,系统总氮去除率提高了17.7%。另外,维持低DO浓度可以实现亚硝酸型同时硝化反硝化反应。     

不同墩高下连续刚构桥抗震性能分析

以某大跨连续高墩刚构桥为依托,采用Midas/civil软件建立仿真模型,通过时程分析方法研究双肢薄壁墩参数在地震响应下对高墩连续刚构桥抗震性能的影响.以桥墩高度为主要参数,以模型阵型频率、桥墩墩顶、墩底位移及内力变化三个方面对其抗震性能进行评价.研究结果表明,随着其中一个桥墩高度的增加,桥梁频率不断减小,矮墩墩底及矮...     

高土石坝震害与抗震措施评述

目前,我国西部地区正建或拟建一大批高土石坝,这些高坝都位于地震高烈度区,做好抗震设计非常重要。本文总结了地震荷载作用下土石坝常见的几种破坏形式,包括地震永久变形、滑坡失稳、液化、防渗体破坏、次生破坏;针对这些破坏形式,总结了地震高烈度区高土石坝的抗震措施,包括预留超高、坡脚压重、坝顶加固、抗液化措施、防渗体处理等;提出了现阶段高土石坝抗震的计算方法和抗震措施存在的缺点和不足,并对我国今后的高土石坝抗震稳定研究提出了建议。     

Immunotoxicity of bisphenol a to Carassius auratus Lymphocytes and macrophages following in vitro exposure

Bisphenol A （BPA） is the monomer component of polycarbonate plastics and classified as an endocrine disrupting chemical （EDC）. The reproductive toxicity of BPA has been extensively studied in mammals; however, relatively little information is available on the immunotoxic responses of fish to BPA. In this study, we investigated the effects of BPA on the immune functions of lymphocytes and macrophages in Carassius auratus. The effects of BPA were compared with those of two natural steroid hormones, estradiol and hydrocortisone. Proliferation of the two types of cells in response to PHA was measured using colorimetric MTT assay. Macrophage respiratory burst stimulated by Con A was measured using chemiluminescence assay. Results showed that BPA （0.054-5.4 mg/L）, estradiol （0.0002-2.0 mg/L） and hydrocortisone （5-50 mg/L） significantly induced Carassius auratus lymphocyte proliferation while higher doses of hydrocortisone （500-5000 mg/L） appeared to be inhibitory. BPA （0.005-50 mg/L）, estradiol （0.005-800 mg/L） and hydrocortisone （0.005-500 mg/L） markedly enhanced macrophage proliferation, whereas higher doses of BPA （500-1000 mg/L） appeared to inhibit cell proliferation. Furthermore, higher dosage of BPA （50 mg/L） and hydrocortisone （50 and 500 mg/L） suppressed the macrophages respiratory burst while estradiol is stimulative all the doses tested （0.05-500 mg/L）. In conclusion, BPA could have immunotoxicity to Carassius auratus and functional changes of lymphocyte and macrophage in Carassius auratus may be different between low and high dosages.     

Biological control experiment of excess propagation of Cyclops for drinking water security

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m^3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish （10 g）, and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.