Comparison of hydrocarbon compositions in a sequence of humic coals, cannel coals and oil shales from the Pictou Coalfield, Nova Scotia

Thirty oil shale, cannel coal and humic coal samples from die Pennsylvanian Stellarton Group, Nova Scotia, Canada have been investigated in this study by means of organic geochemical methods including gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Hydrocarbon compositions of the solvent extracts were found to vary significantly with lithology and facies. Analysis of the saturated hydrocarbon fractions revealed that the relative amounts of long-chain alkanes (>C20) compared to those of short-chain alkanes (<C20) are higher in the humic coal than in the cannel coal and oil shale samples. Moreover, the humic coal is characterized by the presence of homodrimane as the dominant bicyclic alkane. In the oil shale and cannel coal samples, on the other hand, C15-bicyclancs are present as major sesquiterpenoid hydrocarbons. Compounds such as biphenyl, dibenzofuran, fluorene and their mono-mediylated and di-metfiylated homologues were shown to occur almost exclusively in the aromatic hydrocarbon fractions of the humic coal samples. Presumably, these compounds are products of die degradation of lignin during diagenesis. The bitumen compositions of cannel coal and oil shale samples are quite similar. RÉSUMÉ Trente échantillons de schiste bitumineux, de charbon de spores et pollens, et de charbon humique provenant du Groupe de Stellarton (Pennsylvanien de la Nouvelle-Écosse, Canada) ont été analysés dans cette étude à l'aide de méthodes de géochimie organique comprenant la chromatographic en phase gazeuse (GC) et le couplage chromatographic en phase gazeuse -spectrométrie de masse (GC/MS). On constata que les compositions d'hydrocarbures des extraits en solvent varient fortement selon la lithologie et le faciès. Une analyse des fractions à hydrocarbures satures révèla que la proportion des alcanes à longue chaine (>C20) par rapport aux alcanes à chaine courte (<C20) est plus élevée dans le charbon humique que dans les échantillons de charbon de spores et pollens et de schiste bitumineux. De plus, le charbon humique est caractérisé par la présence d'homodrimane comme alcane bicyclique principal. Par centre, dans les échantillons de schiste bitumineux et de charbon de spores et pollens, on note la présence de C15j-bicyclanes comme hydrocarbures sesquiterpénoiides majeurs. Certains composes, tels le biphényle, le dibenzofurane, le fluorène el leurs homologues mono- et diméthylés, se retrouvent presqu'exclusivement dans les fractions à hydrocarbures aromatiques des échantillons de charbon humique. Ces composés serai ent leproduit de la dégradation de la lignine durant ladiagenèse. Les compositions bituminiques des échantillons de charbon de spores et pollens et des schiste bitumineux se ressemblent beaucoup. [Traduit par le journal

Коррозионная защита магистральных трубопроводов в грунтах с различной коррозионной активностью

Для написания своей выпускной квалификационной дипломной работы я выбрал тему антикоррозионной защиты магистральных газонефтепроводов, поскольку коррозия одна из важнейших проблем как нефтяной так и газовой промышленности. В данной работе мною были рассмотрены и изучены виды коррозии, способы защиты стальных сооружений от коррозии, так же была изучена катодная, протекторная, электродренажная защита магистральных газонефтепроводов. В процессе работы я изучил изоляционные покрытия, назначение и конструкции изоляционных покрытий, а так же я провел расчет оптимальных параметров катодной защиты магистального трубопровода.To write my final qualification thesis, I chose the topic of anticorrosive protection of gas and oil pipelines, since corrosion is one of the most important problems of both the oil and gas industry. In this work, I examined and studied the types of corrosion, methods of protecting steel structures from corrosion, and also studied the cathodic, tread, and drainage protection of gas and oil pipelines. In the process, I studied the insulation coatings, the purpose and design of the insulation coatings, and I also calculated the optimal parameters of the cathodic protection of the main pipeline

Разработка многопользовательского игрового приложения в жанре «пошаговая стратегия»

Объектом разработки является трехмерное многопользовательское игровое приложение в жанре пошаговая стратегия. Цель работы – создание программного обеспечения для расширения рынка игровой индустрии и популяризации жанра пошаговая стратегия. В результате исследования данная система спроектирована и реализована в полном объёме.The object of development is a three-dimensional multiplayer game application in the genre of turn-based strategy. The purpose of the work is to create software for expanding the market of the gaming industry and popularizing the genre of turn-based strategy. As a result of the research, this system was designed and implemented in full

Эколого-геохимическая оценка территории города Владивосток по данным изучения листьев тополя (Приморский край)

Работа посвящена изучению элементного состава листьев тополя, как биогеохимического индикатора состояния окружающей среды урбанизированных территорий. Исследование проведено на примере города Владивосток.The work is devoted to the study of the elemental composition of the leaves of poplar, as a biogeochemical indicator of the state of the environment of urbanized territories. The study was conducted on the example of Vladivostok

Cohomogeneity one manifolds and selfmaps of nontrivial degree

We construct natural selfmaps of compact cohomgeneity one manifolds with finite Weyl group and compute their degrees and Lefschetz numbers. On manifolds with simple cohomology rings this yields in certain cases relations between the order of the Weyl group and the Euler characteristic of a principal orbit. We apply our construction to the compact Lie group SU(3) where we extend identity and transposition to an infinite family of selfmaps of every odd degree. The compositions of these selfmaps with the power maps realize all possible degrees of selfmaps of SU(3).Comment: v2, v3: minor improvement

Derivation of determinantal structures for random matrix ensembles in a new way

There are several methods to treat ensembles of random matrices in symmetric spaces, circular matrices, chiral matrices and others. Orthogonal polynomials and the supersymmetry method are particular powerful techniques. Here, we present a new approach to calculate averages over ratios of characteristic polynomials. At first sight paradoxically, one can coin our approach "supersymmetry without supersymmetry" because we use structures from supersymmetry without actually mapping onto superspaces. We address two kinds of integrals which cover a wide range of applications for random matrix ensembles. For probability densities factorizing in the eigenvalues we find determinantal structures in a unifying way. As a new application we derive an expression for the k-point correlation function of an arbitrary rotation invariant probability density over the Hermitian matrices in the presence of an external field.Comment: 36 pages; 2 table

Occurrence and temporal variations of TMDD in the river Rhine, Germany

Background, aim, and scope: The chemical substance 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) is a non-ionic surfactant used as an industrial defoaming agent and in various other applications. Its commercial name is Surynol 104® and the related ethoxylates are also available as Surfynol® 420, 440, 465 and 485 which are characterized by different grades of ethoxylation of TMDD at both hydroxyl functional groups. TMDD and its ethoxylates offer several advantages in waterborne industrial applications in coatings, inks, adhesives as well as in paper industries. TMDD and its ethoxylates can be expected to reach the aquatic environment due its widespread use and its physico-chemical properties. TMDD has previously been detected in several rivers of Germany with concentrations up to 2.5 µg/L. In the United States, TMDD was also detected in drinking water. However, detailed studies about its presence and distribution in the aquatic environment have not been carried out so far. The aim of the present study was the analysis of the spatial and temporal concentration variations of TMDD in the river Rhine at the Rheingütestation Worms (443.3 km). Moreover, the transported load in the Rhine was investigated during two entire days and 7 weeks between November 2007 and January 2008. Materials and methods: The sampling was carried out at three different sampling points across the river. Sampling point MWL1 is located in the left part of the river, MWL2 in the middle part, and MWL4 in the right part. One more sampling site (MWL3) was run by the monitoring station until the end of 2006, but was put out of service due to financial constrains. The water at the left side of the river Rhine (MWL1) is influenced by sewage from a big chemical plant in Ludwigshafen and by the sewage water from this city. The water at the right side of the river Rhine (MWL4) is largely composed of the water inflow from river Neckar, discharging into Rhine 14.9 km upstream from the sampling point and of communal and industrial wastewater from the city Mannheim. The water from the middle of the river (MWL2) is largely composed of water from the upper Rhine. Water samples were collected in 1-L bottles by an automatic sampler. The water samples were concentrated by use of solid-phase extraction (SPE) using Bond Elut PPL cartridges and quantified by use of gas chromatography-mass spectrometry (GC-MS). The quantification was carried out with the internal standard method. Based on these results, concentration variations were determined for the day profiles and week profiles. The total number of analyzed samples was 219. Results: The results of this study provide information on the temporal concentration variability of TMDD in river Rhine in a cross section at one particular sampling point (443.3 km). TMDD was detected in all analyzed water samples at high concentrations. The mean concentrations during the 2 days were 314 ng/L in MWL1, 246 ng/L in MWL2, and 286 ng/L in MWL4. The variation of concentrations was low in the day profiles. In the week profiles, a trend of increasing TMDD concentrations was detected particularly in January 2008, when TMDD concentrations reached values up to 1,330 ng/L in MWL1. The mean TMDD concentrations during the week profiles were 540 ng/L in MWL1, 484 ng/L in MWL2, and 576 ng/L in MWL4. The loads of TMDD were also determined and revealed to be comparable in all three sections of the river. The chemical plant located at the left side of the Rhine is not contributing additional TMDD to the river. The load of TMDD has been determined to be 62.8 kg/d on average during the entire period. By extrapolation of data obtained from seven week profiles the annual load was calculated to 23 t/a. Discussion: The permanent high TMDD concentrations during the investigation period indicate an almost constant discharge of TMDD into the river. This observation argues for effluents of municipal wastewater treatment plants as the most likely source of TMDD in the river. Another possible source might be the degradation of ethoxylates of TMDD (Surfynol® series 400), in the WWTPs under formation of TMDD followed by discharge into the river. TMDD has to be considered as a high-production-volume (HPV) chemical based on the high concentrations found in this study. In the United States, TMDD is already in the list of HPV chemicals from the Environmental Protection Agency (EPA). However, the amount of TMDD production in Europe is unknown so far and also the biodegradation rates of TMDD in WWTPs have not been investigated. Conclusions: TMDD was found in high concentrations during the entire sampling period in the Rhine river at the three sampling points. During the sampling period, TMDD concentrations remained constant in each part of the river. These results show that TMDD is uniformly distributed in the water collected at three sampling points located across the river. ‘Waves’ of exceptionally high concentrations of TMDD could not be detected during the sampling period. These results indicate that the effluents of WWTPs have to be considered as the most important sources of TMDD in river Rhine. Recommendations and perspectives: Based also on the occurrence of TMDD in different surface waters of Germany with concentrations up to 2,500 ng/L and its presence in drinking water in the USA, more detailed investigations regarding its sources and distribution in the aquatic environment are required. Moreover, the knowledge with respect to its ecotoxicity and its biodegradation pathway is scarce and has to be gained in more detail. Further research is necessary to investigate the rate of elimination of TMDD in municipal and industrial wastewater treatment plants in order to clarify the degradation rate of TMDD and to determine to which extent effluents of WWTPs contribute to the input of TMDD into surface waters. Supplementary studies are needed to clarify whether the ethoxylates of TMDD (known as Surfynol 400® series) are hydrolyzed in the aquatic environment resulting in formation of TMDD similar to the well known cleavage of nonylphenol ethoxylates into nonylphenols. The stability of TMDD under anaerobic conditions in groundwater is also unknown and should be studied