飞机草提取物对小菜蛾产卵驱避活性的研究

以干扰作用控制指数作为评价指标,测定了飞机草提取物和乙醇提取物的不同萃取物对小菜蛾产卵驱避作用活性。结果表明,飞机草乙醇提取物及其氯仿萃取物对小菜蛾具有较强的驱避作用,驱避效果达80％以上,对小菜蛾起驱避作用的活性成分主要存在于氯仿萃取物中。     

自动固相萃取-高效液相色谱测定炼化废水中多环芳烃的方法研究

通过实验研究建立了自动固相萃取-高效液相色谱测定炼化废水中16种多环芳烃(PAHs)的方法。研究结果表明,利用Agilent Eclipse XDB-C18色谱分离柱,以乙腈和水为流动相,采用梯度淋洗和变化波长的紫外、荧光程序可测定炼化废水中痕量的16种PAHs。最优固相萃取条件为:15mL甲醇改进剂、10mL萃取柱活化溶剂、5mL/min的萃取流速、分3次共计15mL洗脱溶剂、0.5mL/min洗脱速率。在此优化条件下,方法检出限低于HJ 478—2009《水质多环芳烃的测定液液萃取和固相萃取高效液相色谱法》,精密度相对标准偏差(RSD)小于10%,标准曲线线性系数r≥0.999。     

土壤中石油类的监测方法

研究了测定土壤中石油类含量的方法,采用直接用CCl4从土壤中萃取石油类的方法,再借用HJ637—2012《水质石油类和动植物油类的测定红外分光光度法》测定萃取液CCl4中石油类的含量。该分析方法在土壤分析样品为10g时,确定了最佳的萃取剂体积50mL、萃取时间6h、萃取温度55℃等影响测量结果的因素。该方法不仅操作简单、经济、省时、省力,而且测定结果也较为接近真实数值,填补了企业环境保护管理工作中判定土壤污染严重程度时缺少监测分析方法的空白。     

超临界萃取葡萄籽原花青素的研究

葡萄籽中含有葡萄籽油和植物多酚类化合物——原花青素。研究了常温下以超临界萃取方式从葡萄籽中提取原花青素的方法，实验中甲醇或乙醇作为夹带剂可增加原花青素的萃取率。此外，对原花青素的测定方法进行了比较和实验。     

固相微萃取涂层的研究进展

固相微萃取是一种新型的样品前处理技术.萃取头涂层是固相微萃取的核心,涂层的性质对萃取的选择性和灵敏度起着决定性作用,综述了固相微萃取涂层的发展及其应用.     

搅拌棒吸附萃取技术在环境样品分析中的应用

搅拌棒吸附萃取(SBSE)是继固相微萃取(SPME)之后的又一种无溶剂的用于痕量有机物分离和浓缩的技术,其萃取涂层体积大,具有灵敏度高、检出限低、重现性好、不使用有机溶剂等优点。适用于环境样品中挥发性及半挥发性有机物的痕量分析。本文综述了SBSE在环境样品分析中的应用,以及该技术的应用展望。     

紫外分光光度法测定水中石油类物质的有关问题探讨

对紫外分光光度法测定水中石油类物质中，有关萃取剂、萃取技术、标准曲线斜率的稳定性等进行了初步探讨。     

萃取法处理含油污泥技术研究

采用萃取法处理新疆油田含油污泥,通过萃取剂的筛选,萃取温度、萃取剂与含油污泥质量比等因素对除油率的影响,以及萃取液放置时间对萃取剂回收率的影响等进行了实验,结果表明:自主研发的萃取剂ZZEG具有较好的除油率与回收率;较低温度时,萃取温度对除油率影响较大;除油率随萃取剂与含油污泥质量比的增加而提高;萃取液的放置时间对萃取剂的回收率无明显的影响,萃取剂回收率随分馏温度的提高而增加,分馏温度以200℃较为适宜。     

油菜籽粕中蛋白质的提取与分离研究

油菜籽粕中含有丰富的蛋白质，提取的方法也多种多样。比较了不同萃取剂以及同一萃取剂在不同条件下对油菜籽粕中蛋白质萃取率的影响，得出其最佳提取条件是：pH值为11．5、料液比为1：30、温度45℃、提取时间为2h。     

新标在气田回注水石油类测定中的应用探讨

针对现行HJ 637—2012《水质石油类和动植物油类的测定红外分光光度法》在气田回注水石油类测定过程中存在的空白值高、试剂有毒、萃取率低等问题,探讨四氯化碳选取、萃取分层静置时间、萃取剂替代、是否经硅酸镁吸附等试样制备和数据测定影响因素,在保证测定结果准确度的前提下,对石油类测定的操作技术进行了一些改进。     

Comparative analysis of partial structures of a peat humic and fulvic acid using one- and two-dimensional nuclear magnetic resonance spectroscopy

Nuclear magnetic resonance (NMR) resonance integrals obtained from one-dimensional NMR spectra provide semiquantitative contents of humic constituents with limited resolution in structural detail. When supplemented by connectivity information available from homo- and heteronuclear two-dimensional NMR spectra a more reliable assignment of humic substructures becomes available. This is demonstrated with a comparative one- and two-dimensional NMR analysis of a fulvic and a humic acid obtained from Eriophorum peat. An example of a detailed analysis of the proton chemical shift region normally attributed to carbohydrates shows substantial contributions from amino acids, amino and desoxy sugars, and highly oxidized aliphatic chains of intermediate length. The very good resolution of structural detail by a combined analysis of all NMR spectra shows that the effect of the fractionation procedure on the composition and chemical structure of humic materials is very significant. The comparison of the partial structures comprising humic acid (HA) and fulvic acid (FA) of the peat humic materials studied indicates that FA is diagenetically downstream of HA, favoring the biopolymer degradation (BD) model of humification.     

Enzymatic transformation and binding of labeled 2,4,6-trinitrotoluene to humic substances during an anaerobic/aerobic incubation

Organic pollutants are degraded in soil and simultaneously nonextractable residues are formed. However, proof is lacking that this fixation has a detoxifying effect. We investigated the transformation and binding of 2,4,6-trinitrotoluene (TNT) with catechol or soil humic acid as cosubstrates. Carbon-14-labeled TNT and its reaction products were quantified by radiocounting; extractable compounds were identified by high performance liquid chromatography (HPLC). Bound and extractable residues of 15N-labeled TNT and metabolites were studied by 15N nuclear magnetic resonance spectroscopy (15N NMR). Since TNT is not easily transformed under oxidizing conditions an anaerobic/aerobic treatment was used. Anaerobic microorganisms from cow manure were used to reduce TNT during the anaerobic phase and subsequently, a laccase from Trametes villosa was used in the aerobic phase to oxidatively couple the metabolites to humic matter. Seventy-four percent of TNT was immobilized with catechol as cosubstrate, but only 25% with humic acid. With catechol the main extractable component was TNT, while with humic acid it was mostly the metabolite 4-aminodinitrotoluene. For both co-substrates, the spectra of immobilized metabolites obtained by solid-state 15N-cross polarization magic angle spinning (CPMAS) NMR spectroscopy showed signals in the chemical shift region for protonated aromatic amino compounds. However, in the presence of catechol, an additional signal from nonextractable nitro groups was found, which could represent sequestered TNT. The partially reduced metabolites of TNT that formed nonextractable residues in humic acid are not likely to be remobilized easily and are thus regarded as detoxified.     

QUALITY OF RUNOFF FROM MINNESOTA PEATLANDS: I. A CHARACTERIZATION1

ABSTRACT The likelihood of expanded use of Minnesota's 3 million hectares of peatlands prompted the state to initiate a hydrologic study to characterize these groundwater-linked systems. Determining the quality of streamflow from these peatlands was an integral part of the study. Peatlands could be differentiated either on the basis of streamflow quality or on soil-vegetation characteristics. The quality of streamflow from 45 undisturbed peatlands was characterized by collecting samples five times in 1979-80 and analyzing them for 27 water quality characteristics. Runoff pH, specific conductance, alkalinity, calcium, and magnesium were used to classify the peatlands as bog, transition, or fen. Bog runoff was lower (α= 0.05) in pH, calcium, sodium, manganese, and ammonia nitrogen than fen runoff, but was higher in acidity, color, aluminum, humic and fulvic acid, and chemical oxygen demand than fen runoff. Bogs had more fibric peat of a lower pH than fens; fens exhibited tall woody shrubs which were virtually absent on bogs.     

Kinetic effect of humic acid on alachlor degradation by anodic Fenton treatment

Contamination of water often results from the heavy use of agricultural chemicals, and the disposal of aqueous pesticide waste is a concern. Anodic Fenton treatment (AFT) has been shown to be a successful remediation method for pesticides in solution, but the effect of soil on the degradation kinetics of pesticides using this method has not been determined. The purpose of this study was to study the effect of humic acid, as a soil surrogate, on the degradation kinetics of alachlor [2-chloro-N-(2,6-diethylphenyl-N-(methoxymethyl) acetamide], a heavily used herbicide that has been studied in pure aqueous solution by AFT. The AFT consists of a controlled constant delivery of Fenton reagents, using an electrochemical half-cell to deliver ferrous iron. Alachlor was quickly degraded by AFT, and the kinetics were found to obey the previously developed AFT model well. Degradation of alachlor by AFT in humic acid slurry showed that when the amount of humic acid was increased, alachlor degradation was significantly slowed down and the degradation kinetics were shifted from the AFT model to a first-order model. Further experimentation indicated that humic acid not only competes with alachlor for hydroxyl radicals, reducing the degradation rate of the target compound, but also buffers the slurry at near neutral pH, blocking regeneration of ferrous ion from ferric ion and subsequently shifting the kinetics to first order. Degradation of several other pesticides in humic acid slurry also followed first-order kinetics. These results imply that higher concentrations of Fenton reagents will be required for soil remediation.     

风化煤腐植酸增效尿素红外光谱分析

采用碱性混合活化剂处理风化煤,研制腐植酸添加剂,按不同比例添加到尿素熔融液中,采用模拟喷浆造粒的方法,制备3类增效尿素。通过风化煤与添加剂、尿素与增效尿素红外光谱特征对比发现：风化煤经过活化后,碳单键数量降低,碳链缩短,活性腐植酸HA类提取物出现活性官能团,FR类除单键数量减少和碳链缩短外,生成部分胺、酰胺结构;增效剂与尿素在反应过程中,出现了三键和累积双键破坏、稳定性复合物形成、碳链缩短、双键结构增加等变化,但不同类型增效剂对产品红外光谱特征影响存在差异。     

Effect of organic amendment and plant roots on the solubility and mobilization of lead in soils at a shooting range

Lead (Pb) dissolving gradually from spent pellets constitutes a serious environmental risk in and near shooting ranges, and remediation measures are necessary to prevent its movement to deeper soil layers and ground water. In this study, the effectiveness of organic amendment and plant roots in stabilizing Pb was assessed in a microcosm experiment. Planted (Scots pine, Pinus sylvestris L.) and unplanted microcosms consisting of coarse-textured mineral soil covered with Pb-contaminated humic topsoil were coated with uncontaminated peat layers of 1 to 3 cm and incubated for 77 d. In a percolation test, the microcosms were washed with ultra pure water to simulate heavy rain so as to rinse water-soluble lead (Pbw) from the topsoil layer. Although Pbw remained below detection limits in the mineral soils in all test units, acid-soluble lead (Pba) increased. Peat amendment diminished Pba in the mineral soil layer, this effect being more pronounced in planted soils, indicating that Pb was taken up by the plants. The percolation test showed that the effect of Scots pine seedlings on Pb movement was minor when peat was added. A long-term dissolution test revealed that considerably more Pb was released from old pellets into soil extracts than from new ones, whereas only traces of Pb, if any, were dissolved in sterilized pure water.     

A PRELIMINARY STUDY OF THE EFFECTS OF DRAINAGE AND HARVESTING ON WATER QUALITY IN OMBROTROPHIC BOGS NEAR SEPT-ILES,QUEBEC1

ABSTRACT: Runoff and ground-water samples were collected from four ombrotrophic bogs, representing undisturbed and drained/harvested conditions, at two-week intervals during the summer of 1984. Analyses of samples for water quality parameters revealed significant (P < 0.05 level) increases in specific conductance, NH4⁺-N, total dissolved P, Mg, K, and Na and a decrease in the E₄:E₆ ratio (suggesting increased proportions of humic acid) associated with drainage. There were no significant changes in dissolved organic carbon, Ca concentrations, or pH. Comparison of samples collected before, during, and after ditching showed increases in the dissolved organic carbon, NH₄⁺-N, total dissolved P, K, and Na and a decrease in the E₄:E₆ ratio, but these changes were short lived; water quality returned to preditching values after about a week. The observed changes in water quality are small, probably because the peat is very acid (pH 3.0 to 4.5).     

Sorption of apolar aromatic compounds to soil humic acid particles affected by aluminum(III) ion Cross-Linking

Sorption of hydrophobic compounds in soils often shows nonlinearity, competition, and hysteresis. Since such behaviors have been associated with organic polymers in glassy state, it has been postulated that some forms of soil humic substances are glassy. The glassy state is favored by properties that decrease the flexibility of macromolecules, such as cross-linking, presence of unsaturated bonds, and high molecular weight. Polyvalent metal ions, which are abundant in soils, may cross-link humic substances by coordinating to multiple functional groups on different strands. Accordingly, we prepared an Al(3+)-cross-linked humic acid (Al-HA) from the H(+) form (H-HA) of a soil humic acid by a flocculation technique that leaves Al ions bound to organic groups. Sorption of naphthalene and 1,2,4-trichlorobenzene (TCB) on H-HA was nonlinear, competitive, and slightly hysteretic, in agreement with previous studies showing glass transition temperatures of humic acids that lie above room temperature. Nonlinearity, competition, and hysteresis were all enhanced in Al-HA, validating the hypothesis that metal ion cross-linking enhances nonideal sorption. Application of a glassy polymer sorption model reveals that cross-linking increases the affinity of solutes for the hole domain relative to the dissolution domain. The results (i) indicate that isolated, purified soil humic acid behaves like a glassy solid, (ii) indicate that metal-ion cross-linking creates a more rigid-chain structure and supports a link between nonideal sorption and the glassy character of soil organic matter, and (iii) underscore the importance of metal ions on humic structure in relation to sorption of hydrophobic organic compounds.     

The role of condensed organic matter in the nonlinear sorption of hydrophobic organic contaminants by a peat and sediments

This study examines the effect of soil organic matter heterogeneity on equilibrium sorption and desorption of phenanthrene, naphthalene, 1,3,5-trichlorobenzene (1,3,5-TCB), and 1,2-dichlorobenzene (1,2-DCB) by soils and sediments. Two estuary sediments, a Pahokee peat (PP; Euic, hyperthermic Lithic Haplosaprist), and two subsamples (base- and acid-treated peat [TP] and acid-treated peat [FP]) of the peat were used as the sorbents. The contents of black carbon particles were quantified with a chemical extraction method. Petrographical examinations revealed the presence of the condensed soil and sediment organic matter (SOM) in Pahokee peat. The Freundlich isotherm model in two different forms was used to fit both sorption and desorption data. The results show that the sorption and desorption isotherms are generally nonlinear and that the apparent sorption-desorption hysteresis is present for phenanthrene and TCB. Detailed analysis of sorption data for the tested sorbent-sorbate systems indicates that black carbon is probably responsible for sorption isotherm nonlinearity for the two sediments, whereas the humic substances and kerogen may play the dominant role in nonlinear sorption by the peat. This investigation suggests that the microporosity of SOM is important for the hydrophobic organic contaminant (HOC) sorption capacity on the peat.     

ESTABLISHING PRIORITIES IN MINE DRAINAGE REDUCTION A COST-EFFECTIVENESS APPROACH1

ABSTRACT Twenty-seven watersheds in the Susquehanna River Basin are severely degraded by acid mine drainage pollution. Approximately 620 miles of significant tributaries as well as 230 miles of principal rivers are either sterile or intermittently degraded by acid slugs. As a result of the acid discharges, many uses of the streams, such as water supply and recreation, are precluded. In the past, acid mine drainage abatement programs did not look beyond the immediate problem area. No considerations were given to the blending effect of natural alkalinity in other streams. Since the abatement of acid mine drainage pollution is extremely costly, a method of minimizing these costs was needed. The systematic, cost-effectiveness approach, discussed in this paper presents such a method. This system allows the water resources planners to control the allocation of funds for maximizing the abatement of acid mine drainage.