Coagulation Efficiency and Residual Aluminum Content of Polyaluminum Silicate Chloride in Water Treatment     

Baoyu Gao  Qinyan Yue  Bingjian Wang 《洁净——土壤、空气、水》2004,32(2):125-130

A series of polyaluminum silicate chlorides (PASC), which have different OH^—/Al and Al/Si molar ratios, has been prepared by a copolymerization technique and a composite technique, after which the coagulation efficiency and the residual aluminum content of PASC for water treatment were compared with polyaluminum chloride (PAC) by jar test. The experimental results show that PASC has better coagulation efficiency and lower residual aluminum content than PAC, and the PASC prepared by the copolymerization technique gives a better coagulating effect than that prepared by the composite technique. In addition, the OH^—/Al and Al/Si molar ratios have some effect on the coagulation effect and residual aluminum content of PASC in treated water. With increasing OH^—/Al molar ratio and decreasing Al/Si molar ratio, the residual turbidity and residual aluminum content in treated water diminishes. The pH of the water sample also affects the residual aluminum content of the water and there is a lower residual aluminum content in the neutral pH range.  相似文献   

Application of Hydrophobic Interaction Chromatography (HIC) in Water Analysis Anwendung der Hydrophobizitätschromatographie (HIC) in der Wasseranalytik     

F. Fuchs  A. Heidt 《洁净——土壤、空气、水》1994,22(3):121-129

Dissolved high molecular weight organic substances, like humic substances, can be characterized with regard to their molecular weight distribution using gel filtration chromatography (GFC). In addition, the adsorption properties, for example on activated carbon, can be described, if the substances are separated by hydrophobic interaction chromatography (HIC) in different fractions using a chromatographic column with a hydrophobic matrix. The retention time (Rt) of single chemical substances in this column can be used to characterize the hydrophobicity or hydrophility of each compound as well as of the high molecular weight organic matter. The hydrophobic interaction between the matrix of the column and the dissolved chemical compounds also depends on the hydrophobicity of the gel and the composition of the eluent. Relations between retention times, log P-coefficients (octanol/water partition) and K-values of isotherms on activated carbon (Freundlich equation) were found.  相似文献   

Determination of Partition Coefficients for Selected PAHs between Water and Dissolved Organic Matter     

Su‐Jin Kim  Jung‐Hwan Kwon 《洁净——土壤、空气、水》2010,38(9):797-802

The fate and transport of highly hydrophobic chemicals are affected by the partitioning between water and dissolved organic carbon. Large variation in the partition coefficient (K_DOCw) is often found, due to the selection of model organic matter or potential experimental artifacts. To investigate the roles of the type of organic matter on the partitioning of highly hydrophobic compounds, the partition coefficients of eight selected polycyclic aromatic hydrocarbons (PAHs), with 3–6 aromatic rings, were determined using a passive dosing/extraction method between water and model dissolved organic matter (humic acid, fulvic acid, sodium dodecyl sulfate micelle (SDS), and 2‐hydroxypropyl‐β‐cyclodextrin). Although the K_DOCw values for 3–4 ring PAHs in this study were close to those reported in the literature, experimental K_DOCw values between Aldrich humic acid (AHA) and water were higher than values reported in the literature for 5–6 ring PAHs. The K_DOCw values were highest for AHA, followed by SDS and Suwannee river fulvic acid (SFA). The slopes of the linear regression between log K_DOCw and log K_ow were 1.23 (± 0.13), 0.82 (± 0.09), and 0.59 (± 0.13) for AHA, SDS, and SFA, respectively. The differences in the K_DOCw values between AHA and the other organic matter (SDS, SFA, and CD) increased with increasing hydrophobicity of the PAHs, showing that the sorption of highly hydrophobic chemicals to the humic acid fraction may be important in the presence of mixed organic matter.  相似文献   

Behavior of Aluminum Adsorption in Different Compost‐Derived Humic Acids     

Yong‐Hong Lin  Po‐Hsin Su 《洁净——土壤、空气、水》2010,38(10):916-920

Humic acid plays an important role in the distribution of heavy metals in the environment. The aims of this study were conducted to evaluate the spectroscopic characteristics and aluminum (Al) adsorption of humic acids which were extracted from four composts. The functional groups were determined by Fourier transform infrared spectroscopy (FTIR) and solid‐state ¹³C nuclear magnetic resonance spectroscopy (¹³C‐NMR). The results showed that the aromatic groups were all found in the humic acids of the four composts, and the surface of humic acids included carboxylic group, hydroxylic group, and amino group. The experiment of Al adsorption was described by Freundlich equation. It showed that the adsorption of Al by humic acid from compost of cattle manure was higher, but that from the compost of pig manure, lemon manure, tea manure in equal preparation was lower. The adsorptive behavior was different due to the interaction by functional groups ( OH and  COOH) with Al. These results can describe the fate and transportation of Al in the soil of different organic fertilizer.  相似文献   

Acid Rain and Natural Organic Matter (NOM)     

E. T. Gjessing  G. Riise  E. Lydersen 《洁净——土壤、空气、水》1998,26(3):131-136

Twentyfive years of research on the effects of acid rain on rivers and lakes has, to a very small extent, documented changes in the nature and properties of natural organic matter (NOM). In Western Norway, a "whole-watershed-artificial-acidification-experiment" took place in the period 1988–1996. The goals of this long-term experiment were to study the role of NOM in acidification of surface water and the effects of acid precipitation on the quality and properties of NOM. In the HUMEX project (Humic Lake Acidification Experiment) one half of a lake and the corresponding catchment was artificially acidified with H₂SO₄ and NH₄NO₃ over a period of 5 years. The other half of the lake and catchment served as a control. In addition to monitoring of the general chemical composition of the water from the two lake halves, a number of other chemical and biological characteristics were studied. Here, we report the results related to changes in the nature and chemical properties of NOM. During the first few years of acidification, a significantly lower concentration of NOM was recorded in the acidified half of the catchment, compared with the control. However, statistical analyses of all data (covering a 2-years pre-treatment period and 5 years of treatment) related to the concentration of NOM (TOC, colour, and UV absorbance) did not suggest any significant effect on the quantity of NOM. This apparent discrepancy between the initial decrease in the concentration of NOM and no effect when the whole 5-years period is considered, may be due to the results of two different simultaneous processes. The results suggest that there first was a reduction of TOC and colour, as a consequence of the acidification, followed by an increase, perhaps owing to increased fertilisation (nitrogen) and in addition to a general temperature increase during the period. In addition, short-term studies of the aquatic surface microlayers, lipophilicity of the NOM, content of organic sulfur, and molecular size indicate differences in the quality of the NOM between the two lake halves, which could affect light absorption.  相似文献   

Combined Effects of Molecular Size and Electroendosmotic Flow on the Capillary Electrophoretic Behaviour of Humic Substances     

M. De Nobili  G. Bragato  A. Mori 《洁净——土壤、空气、水》1998,26(3):186-190

The electroendosmotic flow (EOF), generated by the migration of solvated ions near the charged capillary surface, is an important factor in determining the capillary electrophoretic behaviour of humic substances (HS). We investigated the electrophoretic mobilities of HS fractions of reduced molecular-weight polydispersity extracted from peat and from a spodosol either in the presence or after suppression of the EOF. When the EOF was not suppressed, HS migrated to the cathode in spite of their negative charge. Fractionation of HS according to molecular size was achieved in polyacrylamide-coated capillaries filled with 0.05 M tris-phosphate buffer. In uncoated capillaries filled with the same buffer, all fractions had very close mobilities. Addition of polyethylene glycol MW 4000 at concentrations above its entanglement threshold caused the migration times of larger molecules to increase more than those of smaller molecules. The separation was a linear function of molecular size up to 75000 g mol^–1 for peat HS and to 50000 g mol^–1 for HS extracted from the spodosol.  相似文献   

Degradation and Transformation of Aquatic Humic Substances by Laccase-producing Fungi Cladosporium cladosporioides and Polyporus versicolor     

H. Claus  Z. Filip 《洁净——土壤、空气、水》1998,26(3):180-185

A phenoloxidase-producing fungus – Cladosporium cladosporioides – was isolated from water of a bog lake. At high concentrations of carbon (333 mM) and nitrogen (12 mM), the fungus demonstrated the formation of a laccase and a high ligninolytic activity. After addition of riverine or groundwater humic substances into culture media (ca. 1 mg mL^–1), the fungus showed the ability of degrading (utilizing) of about 60% of these substances. However, the exact quantification of the degree of degradation was difficult because of adsorption of humic matter on fungal mycelium. Reisolated humic substances were lower in aromatic and higher in aliphatic structures. A crude enzyme from the C. cladosporioides culture showed only low activity in decolorizing humic substances, whereas decolorization up to 50% was observed when using a laccase preparation from Polyporus versicolor, and especially in the presence of a redox mediator.  相似文献   

Spectroscopic Characterization of Fulvic Acid Fractions of a Contaminated Groundwater     

M. U. Kumke  C. Zwiener  G. Abbt-Braun  F. H. Frimmel 《洁净——土壤、空气、水》1999,27(6):409-415

Two fulvic acid (FA) samples taken from a former gas production facility in the Southwest of Germany were characterized using advanced fluorescence techniques. Steady-state fluorescence (fluorescence excitation, synchronous fluorescence) as well as time-resolved fluorescence were applied. Distinct differences between the sample B22 FA taken within the contamination plume and the sample B53 FA taken downstream were found. Comparison with a model compound for metabolites and humic substances revealed that due to the downstream passage the characteristics of the dissolved organic matter became more humic-like. The assignment of single classes of compounds in the sample B22 FA is discussed in terms of their synchronous fluorescence spectra and fluorescence decay time distribution.  相似文献   

日本鬼魀蜇伤与P物质和生长抑素的关系及其粗毒对免疫细胞活性影响     

张克凌  刘晓萍  杜卫  于业军  孙衍增  王海青  秦士德 《海洋与湖沼》2000,31(4)

1997年 6月在山东省日照市岚山头附近海域收集日本鬼 ,采用放射免疫学方法检测了注射毒腺粗提物大鼠局部肌肉组织、血浆、脊髓、延髓、中脑、下丘脑及免疫器官内P物质和生长抑素含量变化 ;用MTT法检测了毒腺粗提物在整体和离体条件下对免疫细胞活性的影响 ;用生化方法检测了毒腺组织中透明质酸酶活性。结果表明 ,与对照组大鼠相比 ,实验组大鼠局部肌肉及延髓、中脑、胸腺和脾脏中P物质含量增加 ,而下丘脑中P物质含量下降。生长抑素在中脑、延髓、脊髓、胸腺中显著增高。毒腺粗提物对胸腺细胞和脾细胞的活性具有显著的抑制作用。提示日本鬼蜇伤造成局部症状及其伴随的恶心、呕吐、心慌、胸闷等全身症状和继发感染可能与P物质和生长抑素含量变化有关。  相似文献   

Ageing of Dissolved Halogenated Humic Substances and the Microbiological Influence on this Process     

K. G. Heumann  G. Rdlinger  M. Erbes  I. Heiber  U. Obst  Z. Filip  H. Claus 《洁净——土壤、空气、水》2000,28(4):193-201

The distribution of halogens in various fractions of humic substances (HS), separated by their molecular weight, was found to be different for the different halogens. This was demonstrated for chlorine, bromine, and iodine in sewage and brown water samples by applying inductively coupled plasma mass spectrometry coupled with size‐exclusion chromatography. Quantification of the different fractions of iodinated humic substances was obtained by quadrupole mass spectrometry in connection with the isotope dilution technique using an ¹²⁹I‐enriched spike solution. Quantitative analysis was not possible for the corresponding chlorine and bromine species because of spectrometric interferences in the quadrupole instrument. The ageing of HS/halogen species was followed with respect to possible transformations of these species in a ground and sewage water sample up to eight weeks. Even if a distinct structural variation of the humic substance was observed with time by measuring the UV absorption, chlorine remained in the same molecular weight fraction and only a small change was found for the HS/bromine species after eight weeks. In contrast to these findings a substantial transformation of HS/iodine compounds took place, which demonstrated that the transfer probability of halogens from one to another HS fraction is increased with decreasing strength of the halogen bond to carbon. By comparing the results of an original sewage water sample with a filtered one and with another one which was enriched by microorganisms cultivated from the same original sample, a strong microbiological influence on the transformation of HS/iodine species was found. A quantitative balance of the corresponding HS/iodine fractions was calculated for an ageing period of eight weeks showing that iodine was preferably transferred to newly formed UV active HS substances of high molecular weight. In total, no iodine was released from the humic substances.  相似文献