罗得河积水区地表径流中铝形态的变化

美国东部地区的罗得河流域遭受严重的酸沉降侵蚀,对流域和内湖生态系统产生致毒影响。监测地表水和土壤水中的铝形态及浓度变化是问题关键。该文应用自行设计的改进ＭＩＮＱＬ微机模型对该地区地表径流中铝 动力学变化规律了分析,得出有价值的论述。     

模拟酸雨对酸性土壤铝溶出及其形态转化的影响

研究了我国南方酸沉降区主要土壤类型在模拟酸雨影响下,土壤中铝离子释放及铝形态转化的特点。结果表明,酸雨淋洗造成土壤中铝离子释放,酸雨pH值越低,铝离子释放量越大;酸雨淋洗还造成土壤中铝形态发生变化,酸雨pH越低,土壤中羟基态铝和腐殖质铝含量愈低,交换态铝含量越高,土壤中铝对植物和生态系统的危害性也越大。     

Surface applied water treatment residuals affect bioavailable phosphorus losses in Florida sands

Water treatment residuals (WTR) can reduce runoff P loss and surface co-application of P-sources and WTR is a practical way of land applying the residuals. In a rainfall simulation study, we evaluated the effects of surface co-applied P-sources and an Al-WTR on runoff and leacheate bioavailable P (BAP) losses from a Florida sand. Four P-sources, namely poultry manure, Boca Raton biosolids (high water-soluble P), Pompano biosolids (moderate water-soluble P), and triple super phosphate (TSP) were surface applied at 56 and 224kgPha(-1) (by weight) to represent low and high soil P loads typical of P- and N-based amendments rates. The treatments further received surface applied WTR at 0 or 10gWTRkg(-1) soil. BAP loss masses were greater in leachate (16.4-536mg) than in runoff (0.91-46mg), but were reduced in runoff and leachate by surface applied WTR. Masses of total BAP lost in the presence of surface applied WTR were less than approximately 75% of BAP losses in the absence of WTR. Total BAP losses from each of the organic sources applied at N-based rates were not greater than P loss from TSP applied at a P-based rate. The BAP loss at the N-based rate of moderate water-soluble P-source (Pompano biosolids) was not greater than BAP losses at the P-based rates of other organic sources tested. The hazards of excess P from applying organic P-sources at N-based rates are not greater than observed at P-based rates of mineral fertilizer. Results suggest that management of the environmental P hazards associated with N-based rates of organic materials in Florida sands is possible by either applying P-sources with WTR or using a moderate water-soluble P-source.     

等离子发射光谱法测定铝在驻马店市地表水铝含量调查中的应用

按照地表水监测技术规范(HJ/T91-2002),对驻马店市地表水体进行采样,用等离子体发射光谱法两条铝分析线,对所采各个断面水样中的铝浓度进行分析测定,分析得出了流域内地表水中铝含量的一般特征,为下一步地表水体环境质量标准中增设铝项目的管理提供技术支持。     

活性硅酸混凝剂在有机废水处理中的应用研究

以水玻璃,硫酸铝为主要原料制备一定比例铝离子的活性硅酸混凝剂(简称PSAA,以下同),试验其在处理一些典型的有机废水中的混凝特性及影响因素。实验结果表明,铝离子的添加量及溶液最终pH值对PSAA的混凝特性影响都很大.当SiO₂/Al3+(摩尔比)为1左右时,混凝效果最好;在pH4～10范围内,PSAA有着良好的混凝性能。      

PACS中铝的形态分布及其经验公式

利用AlCl₃·6H₂O,Na₂SO₄和NaOH为原料制备了一系列具有不同Al3+/SO2₄-摩尔比及碱化度的PACS样品,利用Al-Ferron逐时络合比色法就Al3+/SO2_４-摩尔比及碱化度对PACS中铝的形态分布影响进行了实验研究,得到了一系列实验结果,建立了PACS中铝的水解形态分布与Al3+/SO2₄-摩尔比和碱化度之间的数学模型,数据拟合结果与实验结果比较,证明二者基本吻合。      

饮用水水质安全性的探讨

阐明了目前我国城镇供水水质安全所存在的问题：主要从藻毒素、消毒副产物、内分泌干扰物、铝浓度超标、出厂水的二次污染等五个方面加以讨论,且分析了它们的危害及产生原因。     

Potential acute effects of suspended aluminum nitride (AlN) nanoparticles on soluble microbial products (SMP) of activated sludge

The study aims to identify the potential acute effects of suspended aluminum nitride (AlN)nanoparticles (NPs) on soluble microbial products (SMP) of activated sludge. Cultured activated sludge loaded with 1, 10, 50, 100, 150 and 200 mg/L of AlN NPs were carried out in this study. As results showed, AlN NPs had a highly inverse proportionality to bacterial dehydrogenase and OUR, indicating its direct toxicity to the activated sludge viability. The toxicity of AlN NPs was mainly due to the nano-scale of AlN NPs. In SMP, AlN NPs led to the decrease of polysaccharide and humic compounds, but had slight effects on protein. The decrease of tryptophan-like substances in SMP indicated the inhibition of AlN NPs on the bacterial metabolism. Additionally, AlN NPs reduced obviously the molecular weight of SMP, which might be due to the nano-scale of AlN.     

Novel synthesis of aluminum hydroxide gel-coated nano zero-valent iron and studies of its activity in flocculation-enhanced removal of tetracycline

A newly designed aluminum hydroxide gel-coated nanoscale zero-valent iron(AHG@NZVI)with enhanced activity and dispersibility of NZVI was successfully synthesized.The AHG@NZVI composite was synthesized via control of the surface AHG content.AHG@NZVI-1,AHG@NZVI-2 and AHG@NZVI-3 were prepared under centrifugal mixing speeds of 1000,2000 and 4000 r/min,respectively.The activity of AHG@NZVI was evaluated by its tetracycline(TC) removal efficiency.The effects of AHG content,pH value,reaction temperatu...     

Profiles of and variations in aluminum species in PAC-MC used for the removal of blooming microalgae

Polyaluminum chloride modified clay (PAC-MC) is a safe and efficient red tide control agent that has been studied and applied worldwide. Although it is well known that the distribution of hydrolytic aluminum species in PAC affects its flocculation, little is known about the influence of particulars aluminum species on the microalgae removal efficiency of PAC-MC; this lack of knowledge creates a bottleneck in the development of more efficient MCs based on aluminum salts. The ferron method was used in this study to quantitatively analyze the distributions of and variations in different hydrolytic aluminum species during the process of microalgae removal by PAC-MC. The results showed that Al_a, which made up 5%–20% of the total aluminum, and Al_p, which made up 15%–55% of the total aluminum, significantly affected microalgae removal, with Pearson's correlation coefficients of 0.83 and 0.89, respectively. Most of the aluminum in the PAC-MC sank rapidly into the sediments, but the rate and velocity of settlement were affected by the dose of modified clay. The optimal dose of PAC-MC for precipitating microalgae was determined based on its aluminum profile. These results provide guidance for the precise application of PAC-MC in the control of harmful algal blooms.