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The generation of runaway electrons (REs) is observed during the low-density helium ohmic plasma discharge in the Experimental Advanced Superconducting Tokamak (EAST). The growth rate of hard x-ray (HXR) is inversely proportional to the line-average density. Besides, the RE generation in helium plasma is higher than deuterium plasma at the same density, which is obtained by comparing the growth rate of HXR with the same discharge conditions. The potential reason is the higher electron temperature of helium plasma in the same current and electron density plateau. Furthermore, two Alfvén eigenmodes driven by REs have been observed. The frequency evolution of the mode is not fully satisfied with the Alfvén scaling and when extension of the Alfvén frequency is towards 0, the high frequency branch is ~50 kHz. The different spatial position of the two modes and the evolution of the helium concentration could be used to understand deviation between theoretical and experimental observation.

Prediction of lithology distribution is critical for development of oilfield and is also one of the basic tasks of geological modeling. Stochastic simulation has been proved to be an effective method for simulation the distribution of lithology. While stochastic simulation technique is theoretically a mathematical method, the result of simulation will be strongly affected by many factors, such as the quantity, quality, and distribution of well data, and so on. In the area or oilfield with limited wells and insufficient data, the uncertainty of simulation result will be very high, and the reliability of the result will be very low. This result with high uncertainty and low reliability will lead to very poor prediction of sand and shale. Further, the reliability of the result of petrophysical modeling will be low. This article introduces a new method by using constraint condition with high quality to improve the simulation result of lithology distribution and decrease the uncertainty of simulation result. Stratigraphic forward modeling is an effective approach to simulate the process of deposition, and this approach can characterize the geometry and distribution of complex sedimentation. But the resolution of the simulation result of this approach is lower than the requirement of development stage of oilfield. Seismic inversion has been proved to be an effective way with high resolution to describe the distribution of lithology by using high-quality seismic data, while seismic inversion is difficult to reflect the geological process and pattern. The combination of these two methods can provide good constraint condition for stochastic simulation. By using the results of stratigraphic forward modeling and seismic inversion, we can build the trend models for different lithology. The trend models can be used in stochastic simulation, and the trend models can improve the result of stochastic simulation. This paper took A oilfield in Oriente Basin in Ecuador as an example to show the process of this method. We built the stratigraphic forward modeling model based on the geological understanding and completed the research of seismic inversion of M1 layer of Napo Formation. The result of serigraphic forward modeling and seismic inversion was resampled into the geological model. Based on these two results, the trend models of sand and shale of M1 layer have been completed. The trend models have been used to constrain the stochastic simulation of lithology with sequential indicator simulation algorithm. This method can effectively decrease the uncertainty of simulation result caused by insufficient well data and improve the reliability of lithological model which further improves the result of petrophysical modeling.

The Napo Formation of the Oriente Basin plays an important role in the hydrocarbon exploration and production of the Ecuador. This study is based on the data of T block which is located in the eastern part of Ecuador. Evolution sequence is divided through seismic and logging data; facies is determined by core description for each sequence; and finally, the sediment evolution of the Napo Formation can be delineated clearly. The Napo Formation is a transgressive system, where five sequences were formed with the changing sea level. Superimposed retrogradational facies is typical in these sequences. Facies analysis indicates that “T,” “U,” and “M1” units are tide-dominated estuarine deposits involving tidal channel, tidal bar, sand flat, and marsh. In addition, residual delta sandstones were found in the lower part of the “M1” unit, but which is distributed in restricted zones and is hard to identify. Those delta sandstones may indicate that there is a delta before the tide-dominated estuarine deposits. Sedimentary facies changed to shallow-marine shelf in the upper parts of the sequences due to the rising sea level, and marlstone deposited. Based on the facies and sequence study, the sedimentary system and sediments evolution can be known in the Napo Formation. This is helpful to understand the sedimentary conditions of the Napo Formation in the slope belt of the Oriente Basin.

A yellow-pigmented, Gram-negative, rod-shaped, non-spore-forming bacterium, strain CC-TPE-1T, was isolated from oil-contaminated soil near an oil refinery located in Kaohsiung County, Taiwan. 16S rRNA gene sequence analysis of strain CC-TPE-1T showed highest sequence similarity to Novosphingobium naphthalenivorans TUT562T (98.1 %), N. panipatense SM16T (97.9 %) and N. mathurense SM117T (97.6 %) and lower (Novosphingobium species. DNA–DNA hybridizations of strain CC-TPE-1T with N. naphthalenivorans DSM 18518T, N. panipatense SM16T and N. mathurense SM117T showed low relatedness of 30 % (reciprocal 35 %), 29.1 % (reciprocal 30.6 %) and 35 % (reciprocal 23.6 %), respectively. The major respiratory quinone was ubiquinone Q-10, the predominant fatty acid was C18 : 1 ω7c (49.9 %) and three 2-hydroxy fatty acids, C14 : 0 2-OH (8.2 %), C15 : 0 2-OH (2.45 %) and C16 : 0 2-OH (1.05 %), were detected. Polar lipids consisted mainly of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, phosphatidyldimethylethanolamine, two sphingoglycolipids, phosphatidylmonomethylethanolamine and several unidentified lipids, and a yellow pigment was also detected. The polyamine pattern contained the single major compound spermidine. Characterization by 16S rRNA gene sequence analysis, physiological parameters, pigment analysis and polyamine, ubiquinone, polar lipid and fatty acid compositions revealed that strain CC-TPE-1T represents a novel species of the genus Novosphingobium, for which we propose the name Novosphingobium soli sp. nov., with the type strain CC-TPE-1T (=DSM 22821T =CCM 7706T =CCUG 58493T).

The statistical analysis of heating effect and the cross-correlation analysis of both electron temperature and loop voltage have been done during electron cyclotron resonance heating (ECRH). The behavior of runaway electrons in the flat-top phase during ECRH are analyzed using experimental data. It is shown that the runaway population is indeed suppressed or even quenched when the toroidal electric field ET is reduced below the threshold electric field Eth by high-power and long-duration ECRH. The physical mechanism of runaway suppression is explored by the resonant interaction between the electron cyclotron waves and the energetic runaway electrons.

A motile, Gram-negative, pinkish red-pigmented bacterium (strain CC-Hsuan-617(T)) was isolated from an oil-contaminated soil near an oil refinery located in Kaohsiung County, Taiwan. 16S rRNA gene sequence analysis showed that strain CC-Hsuan-617(T) clustered with Algoriphagus mannitolivorans (97.5 % sequence similarity), Algoriphagus aquatilis (98.0 %) and Algoriphagus boritolerans (97.5 %), followed by Algoriphagus ornithinivorans (97.1 %) and Algoriphagus alkaliphilus (97.1 %). The fatty acid profile of the novel strain was slightly different from those reported for recognized Algoriphagus species. The quinone system contained menaquinone MK-7 as the predominant component. The major polar lipids were phosphatidylethanolamine, an unknown polar lipid, an unknown phospholipid and an unknown aminophospholipid. The main cell polyamine was sym-homospermidine; lesser amounts of spermine and spermidine were also found. The results of DNA-DNA hybridization, and physiological and biochemical tests allowed the genotypic and phenotypic differentiation of strain CC-Hsuan-617(T) from recognized Algoriphagus species. Strain CC-Hsuan-617(T) is thus considered to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus olei sp. nov. is proposed. The type strain is CC-Hsuan-617(T) (=BCRC 17886(T)=CCUG 57471(T)).

A polyphasic taxonomic study was performed on a pink-coloured unknown bacterium isolated from discarded road tar. Comparative analysis of the 16S rRNA gene sequence demonstrated that the isolate belongs phylogenetically to the genus Azospirillum with Azospirillum lipoferum, A. melinis and A. rugosum as its closest phylogenetic relatives (96.7, 96.6 and 96.6 % similarity to the respective type strains). The generic assignment was confirmed on the basis of chemotaxonomic data, which revealed a fatty acid profile characteristic for the genus Azospirillum, consisting of straight-chain saturated and unsaturated fatty acids, with C(18 : 1)omega7c as the major unsaturated non-hydroxylated fatty acid, and C(16 : 0) 3-OH as the major hydroxylated fatty acid, and a ubiquinone with ten isoprene units (Q-10) as the predominant respiratory quinone. On the basis of both the phenotypic and molecular genetic evidence, it is proposed that the unknown isolate should be classified within a novel species of the genus Azospirillum, for which the name Azospirillum picis sp. nov. is proposed. The type strain is IMMIB TAR-3(T) (=CCUG 55431(T) =DSM 19922(T)).

Three diesel-degrading bacterial strains, Alcaligenes piechaudii CC-ESB2, Gordonia hirsuta CC-GH1 and Rhodococcus ruber CC-RR1, isolated from an oil contaminated site were tested for their hydrocarbon degrading potential. Various traits include oxygen requirement, salinity tolerance, floating activity, cell surface hydrophobicity, emulsification activity, surface tension reduction and hydrocarbon utilization were tested for the exploration of oil degrading candidates. These parameters were assessed in this study which served as indicators for the bioremediation of contaminated soils, groundwater and marine environments.