Characterization of eco-cement paste produced from waste sludges

In this study, marble sludge, sewage sludge, drinking water treatment plant sludge, and basic oxygen furnace sludge were used as replacements for limestone, sand, clay, and iron slag, respectively, as the raw materials for the production of cement in order to produce eco-cement. It was found that it is feasible to use marble sludge to replace up to 50% of the limestone and also that other materials can serve as total replacements for the raw materials typically used in the production of cement. The major components of Portland cement were all found in eco-cement clinkers. The eco-cement was confirmed to produce calcium hydroxide and calcium silicate hydrates during the hydration process, increasing densification with the curing age. The compressive strength (S_c) and microstructural evaluations conducted at 28 d revealed the usefulness of eco-cement. It was observed that the S_c data correlated linearly with the pore volume (P) data at 28 d. The proposed model equation could be represented as S_c = 178-461P (correlation coefficient, R² = 0.96). Two parameters, the large capillary pore volume and the medium capillary pore volume, were evaluated using multiple regression analysis.     

新型混凝剂在印染废水处理中的应用

主要对用于印染废水处理的天然高分子型混凝剂、生产废物型混凝剂和微生物混凝剂的研究现状进行综述,分析了各类混凝剂的特点,并对混凝剂的发展趋势进行了展望。     

豆腐柴叶胶冻形成条件及保鲜护色研究

从促凝剂、复配促凝剂、高温漂烫叶片、冷藏冷冻叶片4个方面对豆腐柴叶胶冻的形成条件做了探讨。结果表明,对豆腐柴叶汁的促凝效果最佳单一试剂为CaCO3,效果最佳的复配试剂为CaCO3-CaCl2,经95℃高温漂烫10s叶片或叶片汁液冷冻3个月后均能形成黄绿色的胶冻。     

不确定背景环境下车道检测技术的研究

针对不确定背景的交通环境,提出一种新的车道检测算法。确定道路路面的色彩范围,提取车道标线的色彩信息,消除光照强度变化对车道标线信息提取过程的影响;通过对比车辆与车道标线在大小、形状和运动模式3方面的差异排除车道中车辆对车道线检测的干扰;单帧图像的车道检测结果存储于车道一致性确认模块中,运用车道标志线一致性确认提高车道检测结果的准确性。试验结果表明,该方法能够有效地检测各种天气条件下车道区域以及解决车道遮挡问题。     

Mapping giant salvinia with satellite imagery and image analysis

QuickBird multispectral satellite imagery was evaluated for distinguishing giant salvinia (Salvinia molesta Mitchell) in a large reservoir in east Texas. The imagery had four bands (blue, green, red, and near-infrared) and contained 11-bit data. Color-infrared (green, red, and near-infrared bands), normal color (blue, green and red bands), and four-band composite (blue, green, red, and near-infrared bands) images were studied. Unsupervised image analysis was used to classify the imagery. Accuracy assessments performed on the classification maps of the three composite images had producer’s and user’s accuracies for giant salvinia ranging from 87.8 to 93.5%. Color-infrared, normal color, and four-band satellite imagery were excellent for distinguishing giant salvinia in a complex field habitat.     

大体积进样与分流/不分流进样气相色谱/质谱测定二噁英的对比

选取传统分流／不分流进样技术与大体积进样技术,结合气相色谱／质谱测定条件,对二者的测定效果和不同进样量的色谱图进行了分析对比。结果表明,使用大体积的进样测定二噁英,在不影响色谱分离度的同时可以大幅度提高仪器分析的灵敏度,可以代替传统分流／不分流进样。     

基于三波长透射率的水体色度检测标准

为了推动有关分光光度法测量水体色度的国家标准的建立,对美国和台湾地区的水体色度标准检测方法进行了研究,提出了新的基于三波长透射率测量水体色度的方法。根据现行国家标准中的色度学相关数据,选择在595、555和445 nm 3个波长处的光谱透射率计算水样的三刺激值,依照国标推荐的色差公式建立了测量水样色度的标准检量线。利用所提出的新的水体色度测量方法对5个水样的色度值进行了实际测量,结果表明,新的测量方法所得到的水体色度值与铂钴比色法一致。     

混凝+芬顿法对中晚期垃圾渗滤液色度去除

垃圾渗滤液经一般生化处理后色度很大。对混凝和芬顿法结合深度处理垃圾渗滤液对色度去除进行了研究。混凝段通过中心复合设计(简称CCD)和响应面方法(简称RSM)分析了混凝的色度去除率的响应特征,建立了实际因素的最终方程模型:Y(色度去除率,%)=-553.40+73.74A+229.06B+0.38AB-34.16A2-22.67B2,(Y、A、B分别代表色度去除率、投加量和pH)并对絮凝条件进行优化,得到混凝反应的最佳优化条件:投加量1.11 g/L,pH 5.06,及在此条件下的去除率67.2%。在芬顿段,将芬顿反应对水中亲水性有机物相对含量(UV254)与对色度的去除特征相结合进行了研究,证明色度的去除跟该类有机物的去除有关,色度去除率最优值条件选择为H2O2/COD=1.0,Fe2+/H2O2=0.35∶1,而初始pH=2.5时对色度的去除达到99%以上。整个工艺出水可达到达标排放标(GB16889-2008)。     

共价键型有机硅铝复合絮凝剂的混凝效果

利用正硅酸乙酯(TEOS)、二乙氧基二甲基硅烷(DEDMS)和γ-氨丙基二乙氧基甲基硅烷(APDES)3种硅烷偶联剂作为有机硅源,制备了共价键型有机硅铝复合絮凝剂,研究了共价键型有机硅铝复合絮凝剂处理浊度水、色度水、含油废水以及垃圾渗滤液膜浓缩液的效果。结果表明,3种共价键型有机硅铝复合絮凝剂具有优良的除浊脱色性能,其除油效果远远优于无机高分子絮凝剂。对于垃圾渗滤液膜浓缩液,共价键型有机硅铝复合絮凝剂可以去除常规絮凝剂无法去除的物质,显著降低出水COD。3种共价键型絮凝剂中,以TEOS为硅源的共价键型絮凝剂除浊效果最佳,以APDES为硅源的共价键型絮凝剂除油和去除COD效果最佳。共价键型有机硅铝复合絮凝剂在含油废水和高浓度有机废水的深度处理方面有很好的应用前景。     

采用Design-Expert软件优化高频气力分选机风量配合设计

采用Design-Expert 7.1.3软件对高频气力分选机的3个风量进行试验方案设计和结果分析.结果表明:在其他操作条件一定的前提下,3个风量对分选效率的影响均为显著;采用Design-Expert 7.1.3软件对3个风量进行正交试验设计,可以有效分析3个风量对高频气力分选机分选效率的影响,并通过试验结果分析建立数学模型,最终得到满足试验要求的风量配合比,最优风量配合比为55∶60∶80.