城镇有机垃圾两相厌氧消化中有机物水解溶出试验

为了促进两相厌氧消化的水解酸化相中有机物的水解溶出,以生活垃圾中COD、VS溶出量为研究参数,试验研究了动态的喷淋和静态的浸泡对城市生活垃圾有机物水解溶出的影响,厌氧、厌氧与好氧交替作用、厌氧与兼氧交替作用、用UASB出水浸泡以及添加猪粪对有机物水解溶出的影响,试验结果表明采用浸泡方式的溶出效率优于采用喷淋的方式,用UASB出水浸泡具有最佳的溶出效率,有机垃圾和畜禽粪便的联合溶出规律与有机垃圾溶出规律基本一致。

污水污泥间壁热干燥实验研究

研究了污泥间壁热干燥的工艺过程，分析了其工艺参数、冷凝水水质和产生的污染气体，探讨了有机物水解机理．结果表明，污泥含水率与停留时间呈负指数函数相关．收集到的干燥冷凝水属高浓度有机废水，其总有机碳（TOC）、挥发性有机酸（VFA）和氨氮（NH3-N）浓度均很高，pH值保持在9—9．5．干燥冷凝水中挥发性有机酸和氨氮来源于2部分：低温110—130℃时，主要发生蛋白质的水解，生成有机酸和氨氮；高温140—150℃时，主要发生脂肪类的水解，生成有机酸．干燥温度低于150℃时，污泥间壁热干燥过程无污染气体产生．

纳米钡铁氧体制备技术的研究进展

综述了近年来在M型(磁铅石结构)钡铁氧体超微粉体合成领域的一些研究进展,包括低温化学法、喷雾热解法、化学共沉淀法、水热法、玻璃结晶化法、微乳液法、金属有机物水解法、有机树脂法、自蔓延高温合成法、溶胶-凝胶法等,并分析了上述制备方法的优缺点。

Preparation of Photocatalytic TiO_2 and TiO_2-SiO_2 Particles and Application to Degradation of Trace Organics in Aqueous Solution

TiO2 and TiO2-SiO2 photocatalysts were prepared by sol-gel and supercritical CO2 fluid drying method and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), etc. Their catalytic properties were tested through the photocatalytic degradation of phenol and aniline in wastewater. The results show that the developed fluidized photocatalytic reactor (FPR) and TiO2 catalyst had better performance in degrading pollutants as compared with slurry photocatalytic reactor (SPR) and commercial TiO2 catalyst. The composition and crystal form of TiO2-SiO2 composite oxide had obvious influence on catalytic effect and TiO2-SiO2 photocatalysts showed better catalytic activity and stability.

Relation of Mineralizable N to Organic N Components in Dark Loessial Soils

Mineralizable N and organic N components in different layers (0～15, 15～30,30～45, 45～60, 60～80 and 80～100 cm) of six soils with different fertilities sampled from YongshouCounty, Shaanxi Province, China, were determined by the aerobic incubation method and the Bremnerprocedure, respectively. Correlation, multiple regression and path analyses were performed to studythe relation of mineralizable N to organic N components. Results of correlation and regressionanalyses showed that the amounts of the N mineralized were parallel to, and significantly correlatedwith, the total acid hydrolyzable N, but was not so with the acid-insoluble N. Of the hydrolyzableN, the amino acid N and the ammonia N had a highly consistent significant correlation with themineralized N, and their partial regression coefficients were significant in the regressionequations, showing their importance in contribution to the mineralizable N. The amino sugar N, onthe other hand, had a relatively high correlation with the mineralized N, but their partialregression coefficients were not significant in the regression equations. In contrast, thehydrolyzable unknown N had no such relations. Path analysis further indicated that the amino acid Nand ammonia N made great direct contributions to the mineralized N, but the contributions of theamino sugar N were very low. These strongly suggested that the mineralized N in the soils tested wasmainly from the hydrolyzable N, particularly the amino acid N and ammonia N which are the majorsources for its production.

Dechlorination of Chlorinated Aliphatic Compounds by Micro-scale Al-Zn-Mg/Fe Powders as Advanced Zero-valent Iron

Micro-scale Al-Zn-Mg/Fe composite powders (MAF) with high reactivity and good storage properties were prepared by reducing iron onto the surface of Al-Zn-Mg alloy powders. Experimental results show that MAF as advanced zero-valent iron are highly effective for degradation of chlorinated organic compounds. The efficiency of degradation for carbon tetrachloride and perchloroethylene is higher than 99% within a period of 2 h. The efficiency of degradation for trichloroethylene by MAF after storing for one month is equivalent to that by freshly prepared nano-size zero-valent iron particles.

Treated results study on organic substance and ammonia from coke plant wastewater by SBR method in different operating mode and aeration time conditions

In this paper, a research was made on the treatment of distillation ammonia wastewater from Tai'an Coke-Plant by SBR(sequencing batch reactors). The feasibility and cost effectiveness was tested. Performance of SBR process treating organic substance and ammonia was presented for different operating pattern and aeration time. The mechanism of the simultaneous nitrification and denitrification from coke plant were analysed on SBR process.

Detection of tyrosine,trace metals and nutrients in cow dung:the environmental significance in soil and water environments

This study examined the dissolved organic matter(DOM) components of cow dung using a combination of fluorescence(excitation–emission matrix,EEM)spectroscopy and parallel factor(PARAFAC) modelling along with eleven trace metals using ICP-MS and nutrients(NH_4^+ and NO_3^-) using an AA3 auto analyser. EEM–PARAFAC analysis demonstrated that cow dung predominantly contained only one fluorescent DOM component with two fluorescence peaks(Ex/Em=275/311 nm and Ex/Em=220/311 nm),which could be denoted as tyrosine by comparison with its standard. Occurrence of tyrosine can be further confirmed by the FTIR spectra. Trace metals analysis revealed that Na,K and Mg were significantly higher than Ca,Fe,Mn,Zn Sr,Cu,Ni and Co. The NH_4^+ concentrations were substantially higher than NO_3^-.These results thus indicate that the dissolved components of the cow dung could be useful for better understanding its future uses in various important purposes.

Effects of extra-cellular polymeric substances on organic pollutants biodegradation kinetics for A-step of adsorption-biodegradation process

The features of organic pollutants degradation mainly characterized by bio-flocculation for step-A of adsorption-biodegredation（AB） process were studied. By investigating the relationship of extracellular polymeric substances（EPS） with bioflocculation and introducing kinetic model of organic pollutant degradation into EPS, the kinetic model of organic pollutant degradation for step-A hioflocculation was deducted. And through the experiments, the kinetic constants were calculated as follows： k1 =0. 005 3; kc1 =1 710.7 and vmax1=10 min^-1.

Chemical characterization and composition of dissolved organic matter in Jiaozhou Bay

Biologically utilizable dissolved organic compounds,including dissolved organic carbon (DOC),dissolved carbohydrates (DCHO) and dissolved free amino acids (DFAA) were analyzed in filtered surface seawater samples collected at 19 stations in Jiaozhou Bay,China,on June 3,2007.In these samples,concentrations of DOC,dissolved free carbohydrates (DFCHO),dissolved combined carbohydrates (DCCHO),total dissolved carbohydrates (TDCHO) and total dissolved free amino acids (TDFAA) ranged from 141.7 to 191.1 μmol C/L,1.98 to 18.18 μmol C/L,5.04 to 24.90 μmol C/L,14.52 to 30.36 μmol C/L,and 1.83 to 11.89 μmol C/L,respectively.As a major component of the dissolved carbohydrates,the concentrations of DCCHO were about three times higher than those of DFCHO.Three major constituents of the DFAA were threonine (23.0±5.7 mol%),glutamic acid (16.6±3.2 mol%) and arginine (9.1±3.3 mol%).Based on the composition of DFAA,a molar C:N ratio of 3.60±0.75 in DFAA was derived,indicating longer carbon chains in the amino acids.DCCHO (8.1%) was the most abundant fraction of DOM in most samples,followed by DFCHO (4.8%) and TDFAA (2.7%).These DOM concentrations displayed a decreasing trend from the coast to the central region.Significant correlations were found between the DCCHO and DFCHO concentrations (r=-0.724,n=19,P<0.001) and the DCCHO and TDCHO concentrations (r=0.506,n=19,P=0.027).

Thermal catalysis under dark ambient conditions in environmental remediation:Fundamental principles, development, and challenges

Thermal catalytic degradation of organic pollutants conducted in the dark at room temperature under atmospheric pressure without the need of external chemicals and energy sources has attracted a lot of attention over the last two decades. It provides unparalleled advantages over other advanced oxidation processes (AOPs) in treating domestic and industrial contaminated wastewater from the viewpoint of energy/chemical conservation and ease of operation. Rich knowledge has been accumulated in terms of the synthesis and application of thermal catalysts though controversies remain regarding their underlying mechanisms. This review sheds light on the proposed thermo- catalysis mechanism for the first time and presents the development of thermal catalysts under dark ambient conditions with a focus on catalyst materials, catalytic activity, and mechanism. The present review aims to provide mechanistic insights into the rational design of novel and efficient catalysts, and their underlying mechanisms as well as the emerging challenges and perspectives in thermo-catalysis under dark ambient conditions used for the practical and efficient treatment of contaminated wastewater.

Study on Water－Soluble Organic Reducing Substances：Ⅲ．Electrochemical Properties of Decomposition Products of Rice Straw and Their Interactions with Variable Charge Soils

Some electrochemical properties,such as PH,Eh,and voltammetric behavior,of the decomposition products of rice straw and the in eractions of these products with soils were studied.The PH,Eh,and amounts of organic reducing substances changed markedly during the 60-day anaerobic decomposition.pH decreased sharply to pH 5 on the tenth day and then increased gradually to 7 on the 45th day.The amouats of organic reducing substances increased almost synchronously with the fall of redox potential during the first 15 days.The differential pulse voltammetric(dpv) behavior changed not only in the peak current but also in the peak potential.The fractions with apparent molecular weights lower than 200 dations appeared to be active in dpv behavior.The electric charge of organic reducing substances was closely related to the decomposition stage.The 6th day of incubation was the crucial time before and after which the major part of the components was negatively charged and positively charged, respectively.The group with a low apparent molecular weight and a negative charge was the main components responsible for the lower anodic peak potentials.They were oxidized first during the interactions of the organic reducing substances with soils.

Spatiotemporal variation of dissolved carbohydrates and amino acids in Jiaozhou Bay,China

Surface seawater samples were collected from Jiaozhou Bay,China,during six cruises(MarchMay 2010,September-November 2010) to study the distribution of dissolved organic matter including dissolved organic carbon(DOC),total dissolved carbohydrates,namely monosaccharides(MCHO) and polysaccharides(PCHO) and total hydrolysable amino acids.These included dissolved free amino acids(DFAA) and combined amino acids(DCAA).The goal was to investigate possible relationships between these dissolved organic compounds and environmental parameters.During spring,the concentrations of MCHO and PCHO were 9.6(2.8-22.6) and 11.0(2.9-42.5) μmol C/L,respectively.In autumn,MCHO and PCHO were 9.1(2.6-27.0) and 10.8(2.4-25.6) μmol C/L,respectively.The spring concentrations of DFAA and DCAA were 1.7(1.1-4.1) and 7.6(1.1-31.0) μmol C/L,respectively,while in autumn,DFAA and DCAA were 2.3(1.1-8.0) and 3.3(0.6-7.2) μmol C/L,respectively.Among these compounds,the concentrations of PCHO were the highest,accounting for nearly a quarter of the DOC,followed by MCHO,DCAA and DFAA.The concentrations of the organic compounds exhibited a decreasing trend from the coastal to the central regions of the bay.A negative correlation between concentrations of DOC and salinity in each cruise suggested that riverine inputs around the bay have an important impact on the distribution of DOC in the surface water.A significant positive correlation was found between DOC and total bacteria count in spring and autumn,suggesting bacteria play an important role in the marine carbon cycle.

Nitrogen Forms of Maillard Polymers Derived from Xylose and ^(15)N-Labelled Glycine

Water-soluble, nondialyzable Maillard polymers were prepared by reacting D-xylose with 15N-glycine (and/or glycine) at 68 ℃ and pH 8.0 at equimolar concentrations of 1, 0.5 and 0.1 mol L-1, respectively,for 13 days and partitioned into acid-insoluble (MHA) and acid-soluble (MFA) fractions. The nitrogen forms in these polymers were studied by using the 15N cross polarization-magic angle spinning nuclear magnetic resonance (CPMAS NMR) technique in combination with chemical methods. The 15N nuclear magnetic resonance (NMR) data showed that while the yield, especially the MHA/MFA ratio, varied considerably with the concentrations of the reactants, the nitrogen distribution patterns of these polymers were quite similar.From 65% to 70% of nitrogen in them was in the secondary amide and/or indole form with 24%~25% present as aliphatic and/or aromatic ammes and 5% to 11% as pyrrole and/or pyrrole-like nitrogen. More than half (50%~77%) of the N in these polymers were nonhydrolyzable. The role of Maillard reaction in the formation of nonhydrolyzable nitrogen in soil organic matter is discussed.

Using Magnetic Technique to Increase Efficiency of Organic Pollutants Biodegradation in Wastewater

The intensity of Magnetic field by 200, 300 and 400 gaos were selective to study their impacts on bacteria Bacillus, Pseudomonas and yeasts Candida dubliniensis, Candida glabrata, lssatchenkia orientalis and Rhodotorula mucilaginosa growth and to reduce organic pollutants in wastewater by COD, TOC, TN and TP in concentrations of 180, 75, 52 and 84 ppm in pH 7.6 and treatment periods of 2, 4, 6 and 18 h in batch system. Results showed that magnetic field 300 gaos had higher ability to increase bacterial and yeasts growth by 400-600% in 18 h and reduced COD, TOC, TN and TP by 88, 85, 90 and 98.5% in same period treatment. While, the intensity of magnetic field 200 and 400 gaos have no effect on microorganisms growth and reducing organic pollutants. This study is first record for showing and explaining the positive effective of magnetic field on microorganisms growth.