污泥内层和外层胞外聚合物的三维荧光光谱特性研究

运用三维荧光光谱技术对污泥LB-EPS和TB-EPS的荧光特性进行了研究.实验结果表明,在污泥LB-EPS和TB-EPS中都有三个明显的荧光峰,分别为Peak B(λex/λem=270～280 nm/345～360 nm),Peak C(λex/λem=330～340 nm/410～430 am)和Peak D(λex/λem=390 nm/450～470 nm).其中Peak B为类蛋白荧光(Protein-like)、Peak C为可见区类富里酸荧光(Visible fulvic-like)、Peak D为类腐殖酸荧光(Humic-like).从各荧光峰的荧光强度来分析,LB-EPS和TB-EPS中的主要成分都为类蛋白,然后依次为富里酸和腐殖酸.浓度和pH值对污泥LB-EPS和TB-EPS的三维荧光特性都有很大的影响,但影响程度略有区别,表明作为外层的胞外聚合物,LB-EPS表现出与TB-EPS不全相同的化学结构.     

A comparative study of solvent extraction of total petroleum hydrocarbons in soil

Three non-specific methods for the extraction of total petroleum hydrocarbons (TPH) from soil into organic solvent were compared. The techniques used for sample preparation were Soxhlet extraction, closed-vessel microwave-assisted extraction, and CEN shake extraction. The total concentrations of extracted compounds in the boiling point range of C10–C40 were determined by gas chromatography with flame ionization detection. The best recovery (99%) and repeatability (±3%) from standard oil mixtures were obtained with microwave-assisted extraction. However, the different extraction methods exhibited different behaviour when spiked soil samples were extracted. The best repeatability was obtained with CEN shake extraction (±6%) but the repeatability values for Soxhlet and microwave-assisted methods were quite high (>20%). However, the larger uncertainties of the latter extraction methods does not necessarily limit the applicability of these methods to the determination of petroleum hydrocarbons in soil, as in the assessment of soil contamination the expanded uncertainty of the result is usually not limited by analytical uncertainty, but rather by the uncertainty of the primary sampling stage. However, distinctive variation found in the chromatographic profiles illustrates that discretion should be obeyed when chromatograms obtained after application of different extraction methods on petroleum contaminated samples are to be used in the fingerprinting or age dating studies. Otherwise, misleading conclusions concerning the age of spillage could be drawn.     

The structure of diluted binary solutions of amides according to the heat capacity data

The specific heat capacities of hexamethylphosphoric triamide, diethylpropionamide, their aqueous solutions, and mixtures of hexamethylphosphoric triamide with formamide were measured in the temperature range from 288.15 to 318.15 K. The dependences of the partial molar heat capacity of aqueous solutions of amides on the composition of the mixture have maxima in the region of 0.02–0.04 molar fractions of amide. The maximum on a similar dependence for solutions of hexamethylphosphoric triamide corresponds to the concentration of 0.01 molar fractions. The conclusion on the formation of solvates (hydrates) in the systems studied was made. The heat capacity coefficients of pair and triple interactions were calculated in terms of the McMillan-Mayer theory. A change in the heat capacity characteristics with the temperature change was analyzed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2479–2483, December, 1998.     

杨村烟煤与石油渣油共处理反应特性的研究

用共振搅拌反应器研究了山东兖州杨村的烟煤与北京燕山石化公司的石油渣油共处理液化的反应过程，考察了反应温度和反应时间对煤液化转化率及产物中前涸青烯，苯可溶组分的影响。     

石油焦活化机理的研究

研究了石油焦在高温、碱性条件下的活化机理。扫描电镜和低温N2吸附法测定孔结构结果表明，石油焦在750 ℃～800 ℃下活化得到的产品，比表面达2 900 m2/g，微孔率到90%，吸附甲烷的体积比为115∶1，是较理想的活化反应温度范围。气相色谱分析结果证明，在活化过程中产生的气体为H2，CO2，CO，CH4。X射线衍射结果表明，吸附剂产物属于部分石墨化的无定形体。     

氟甲砜霉素注射液含量及其有关物质的HPLC测定

为建立测定氟甲砜霉素注射液含量的方法,采用高效液相色谱法,选用Agilent EclipseXDB-C8柱(4.6 mm×250 mm,5μm),Lab Alliance C8保护柱(4.6 mm×10 mm,5μm),流动相为(V乙腈) V(水)=35 65,流量1.0 mL.min-1,检测波长224 nm,进量样20μL,柱温为室温。结果表明,方法的线性范围为10.0～400μg.mL-1(r=0.999 6),最低检测限2.0 ng。回收率98.7%～101.2%,RSD 0.30%～1.22%(n=5)。方法简便灵敏,结果准确可靠,可用于氟甲砜霉素注射液的质量控制。     

Intracellular fate of hydrocarbons

In previous work, purification procedures and zymogram analysis conducted with supernatants of crude extracts from aerobic mycelium of the YR-1 strain of Mucor circinelloides isolated from petroleum-contaminated soils indicated the existence of only one soluble alcohol oxidase (sAO) activity. In the present work enzymatic activity of alcohol oxidase (AO) was also detected in the mixed membrane fraction (MMF) of a high-speed centrifugation procedure after drastic ballistic cellular homogenization to break the mycelium from strain YR-1. When mycelial cells were gently broken by freezing the mycelium with liquid nitrogen, smashing in a mortar, and submitting the samples to an isopycnic sucrose gradients (10–60% sucrose), AO activity was detected in particular and discrete fractions of the gradient, showing specific density values quite different from the density of peroxisomes. The results suggest that there could be a different intracellular pattern of distribution of the microsomal fraction in aerobically grown mycelium depending on the carbon source used in the culture media, including alcohols and hydrocarbons, but not in glucose. In working with particulate fractions, we found two AO activities: a new membrane alcohol oxidase (mAO) activity and the sAO. Both activities appear to be located in the inner of the cells in specific compartments different from the peroxisomes, so mAO could be in the membrane of these compartments and sAO in the lumen of the vesicles. We also assayed other enzymatic activities involved in hydrocarbon biodegradation to establish its intracellular location and other enzymatic activities such as peroxidase to use them as intracellular markers of different organelles. In the case of monooxygenase, the first enzymatic step in the hydrocarbon biodegradation pathway, its location was in the same fractions where AOs were located, suggesting the existance of a specific organelle that contains the enzymatic activities involved in hydrocarbon biodegradation.     

Compehensive two-dimensional gas chromatography (GC×GC) and its applicability to the characterization of complex (petrochemical) mixtures

In general, petrochemical products contain only a limited number of chemical classes of compounds (sample dimensionality). The enormous number of individual components within these classes, however, soon puts limitations upon a single chromatographic technique when it comes to adequate characterization of these products. Comprehensive two-dimensional gas chromatography (GC×GC) clearly opens the possibility of estimating the composition of hydrocarbon mixtures in a far more detailed fashion than hitherto possible. Although the emphasis of papers of GCxGC thus far almost exclusively applies to the unsurpassed peak-capacity, in the oil industry there is a need for characterization, rather than for analyzing all the individual compounds. In principle a GCxGC system can provide an almost perfect match between its intrinsic properties and the dimensionality of oil samples. To establish the applicability of GCxGC towards petrochemical analytical challenges, a commercially aavailable prototype instrument was subjected to an exhaustive characterization of a typical hydrocarbon precess stream and a fast characterization of a light gas oil. Although there are no fundamental limitations towards the quantitative aspects of a GCxGC system, this paper confines itself to qualitative results only. Quantitative aspects of GCxGC will be published in a forthcoming paper.     

O-Alkylation of a lignite humic acid by phase-transfer catalysis

A mild phase-transfer catalytic reaction has been conducted to O-alkylate the acidic functions of a lignite humic acid (HA), using tetrabutylammonium hydroxide as the phase-transfer catalyst. The HA acidic functional groups were made to react, in tetrahydrofuran, by nucleophilic substitution with several alkyl halides—methyl iodide, and ethyl, propyl, and butyl, and benzyl bromide. The occurrence of the O-alkylation reaction was assessed by elemental analysis and ¹H NMR, CPMAS ¹³C NMR, and FTIR spectroscopy. Bonding of alkyl groups increased the carbon and hydrogen content and the H/C ratios of all the humic reaction products. Increased nitrogen in the reaction products suggested incomplete removal of the phase-transfer catalyst after purification of the alkylated HA. ¹H NMR and CPMAS ¹³C NMR spectra of alkylated products provided evidence of the successful occurrence of the alkylation reactions. Infrared spectra confirmed the NMR results, revealing the characteristic absorption of newly formed alkyl and aryl ethers and esters in the alkylated products and C–H stretching in the aromatic ring of the benzylated derivative. These findings indicate that humic matter can be successfully alkylated with several different alkylating groups by catalysed phase-transfer reaction. This O-alkylation reaction has the advantage of being mild, versatile, and high-yielding compared with traditional methylation reactions applied to HA. The possibility of introducing different alkyl groups into the HA by a mild phase-transfer reaction may become useful by enabling improved fractionation of humic supramolecular associations and further understanding of the molecular nature of humic substances.     

石油焦与煤混合燃料热重分析研究

石油焦与煤混合燃烧是高效处理石油焦的有效方法，作者对选用的石油焦和煤不同配比的混合燃料进行了热重分析研究。使用常压高温热天平研究、分析了各配比混合燃料的热解特性和燃烧特性。并根据化学动力学方法计算了各过程的化学动力学参数，即活化能E和频率因子A0。结果表明，各混合燃料热解起始温度大致相同，随煤焦比减小，挥发分析出速率变缓，最大释放速度所对应的温度升高，最终失重率减小，挥发分释放特性指数减小；随煤焦比增大，混合燃料着火温度和燃尽温度逐渐降低，最大燃烧速率所对应的温度降低，燃烧特性指数增大；随煤焦比减小，活化能和频率因子增大。