Experimental degradation of crude oil by marine bacteria

The ability of biodegradation for crude oil was examined for ten strains of marine bacteria. With regard to their degradation ability forn-alkanes the microorganisms tested could be divided into four groups, although the same result was not observed for microbial degradation of aromatic hydrocarbons obtained by the UV measurements.     

A micromechanical modeling of ductile behavior of a porous chalk: Formulation,identification, and validation

Porosity strongly affects the overall ductile behavior of cohesive geomaterials undergoing plastic deformation. In the present paper, we proposed an original micromechanical approach that suitably couples Drucker–Prager‐type plasticity, evolving porosity under general triaxial loadings. The resulting model has the advantage to be based on a single macroscopic yield function, which also plays the role of plastic potential. It is shown that this yield function is particularly appropriate to account for the pore collapse and plastic shearing mechanisms that govern the mechanical behavior of the studied Lixhe chalk. Finally, the new model is implemented and validated by comparison to triaxial tests data, covering a wide range of confining pressures. Copyright © 2011 John Wiley & Sons, Ltd.     

Mobilization and speciation of arsenic from hydrothermally altered rock containing calcite and pyrite under anoxic conditions

The effects of water residence time and anoxic conditions on the mobilization and speciation of As in a calcite- and pyrite-bearing altered rock excavated during a road-tunnel project has been evaluated using batch and column laboratory experiments. Higher infiltration rates (i.e., shorter water residence times) enhanced the leaching of As due to the higher pH values of the effluents and more rapid transport of dissolved As through the columns. The concentration of As in the effluent also increased under anoxic conditions regardless of the water residence time. This enhanced leaching of As under anoxic conditions could be attributed to a significant pH increase and decreased Fe oxyhydroxide/oxide precipitation compared to similar experiments done under ambient conditions. Processes that controlled the evolution of pH and the temporal release mechanisms of As under anoxic conditions were identical to those previously observed under ambient conditions: the dissolution of soluble phases, pyrite oxidation, co-precipitation and/or adsorption/desorption reactions. Speciation of As in the column experiments could partly be attributed to the pH-dependent adsorption of As species onto Fe oxyhydroxide/oxide precipitates. Moreover, apparent equilibrium of the total As and As[III] concentrations was delayed under anoxic conditions in both batch and column experiments.     

How do “numbers” construct social reality in disaster-stricken areas?: a case of the 2008 Wenchuan earthquake in Sichuan,China

This article focuses on the dynamics of using numbers to construct an image of social reality in disaster areas. Numbers are neither objective nor value-neutral but are rather generated, transmitted and shared with social signification. In other words, numbers can be thought of as simply socially constructed information. Statistics and other numbers usually work in positive ways. However, it is also possible that using numbers in the media can lead to unintended messages that could produce negative consequences. We conducted field studies in disaster-stricken areas of the 2008 Wenchuan earthquake in China and compared findings to the case of the 1995 Kobe earthquake in Japan in order to examine how numbers—in terms of the amount of donations, the timeline of reconstruction projects and casualty figures—construct social reality and cause a variety of social dysfunctions.     

Large-scale landslides in Toyama Prefecture,central Japan,and their probable relationship with earthquakes

Large-scale landslides along the Kubusu and Besso rivers in Toyama Prefecture are developed in the Miocene Iwaine Formation, which is composed of andesitic lava, tuff, and tuff breccia. In the middle member of this formation, the tuff is easily altered to montmorillonite-bearing rock, and subsequently plays an important role in the development of landslides events, which tend to be large-scale events, as the massive lava of the upper member forms a cap rock over the tuff. The Kiritani and Koinami basins, which are flat intermontane basins located along the Kubusu and Besso rivers, respectively, are interpreted as landslide-dammed lakes, later filled with sediment. Accelerator mass spectrometry ¹⁴C ages show that the landslides forming each dam occurred simultaneously, at approximately 2500 BP. These ages were measured from wood fragments embedded in the landslide material of Kiritani, and from an in situ stump drowned during the impoundment of Koinami. If the trigger of these landslides was an earthquake, it is most likely to have been the penultimate event along the Atotsugawa fault zone.     

A comparative micromechanical analysis of the effective properties of a geomaterial: Effect of mineralogical compositions

In order to provide a physical interpretation of the variation of the mechanical properties of Callovo-Oxfordian argillite with mineral composition, we implement three linear homogenization schemes. The argillite is modeled as a three phase material composed of a clay matrix and inclusions of quartz and calcite. It is shown that, unlike the dilute scheme and the self-consistent scheme, the Mori-Tanaka model describes the in situ experimental data well. The determined properties are finally used in a finite element computation. The aim is to evaluate the effect of mineral composition on the elastic response of the excavation of a vertical shaft in the context of the underground laboratory of Meuse/Haute Marne.     

The nature of megafaunal extinctions during the MIS 3–2 transition in Japan

The nature of late Quaternary megafaunal extinctions has been the subject of intense debate since the 1960s. Traditionally, scientists cite either climatic changes or human predation as the primary reason for worldwide megafaunal extinctions. In many island cases (e.g., Madagascar, New Zealand), scientists have had a tendency to lean toward humans as being the direct or indirect dominant cause for the relatively quick extirpation of indigenous megafaunas. This study evaluates the record for megafaunal (e.g., Palaeoloxodon, Mammuthus, Sinomegaceros) extinctions in the Japanese islands and draw the tentative conclusion that: (1) humans directly and/or indirectly influenced the extinction of some large herbivores; and (2) the megafaunal extinctions likely began earlier than originally proposed; during the marine isotope stage (“MIS”) 3–2 transition (～30–20 ka) rather than during the MIS 2–1 (～15–10 ka) shift that roughly coincides with the advent of the Jomon period in Japan. However, we temper our findings due to the current paucity of sites in Japan that have associated archaeology and vertebrate paleontological materials that date to the MIS 3–2 transition.     

D-INSAR技术在大范围滑坡监测中的应用

对大面积自然山区进行高精度的滑坡灾害监测一直是我国及其它地质灾害频发国家的一个重要课题,尚未得到很好解决。D-INSAR技术是近年来微波遥感发展的一个重要方向,理论上可以以厘米甚至更高的精度对连续大面积的微小地面活动进行监测,被认为是极具应用前景的滑坡灾害监测技术。为此以应用D-INSAR技术对大范围的自然滑坡进行监测和预警为目的,详细地推导了D-INSAR技术监测形变的原理公式并介绍了方法和数据处理流程,在全面回顾该技术在国内外滑坡监测中的应用现状和实例的基础上,分析了D-INSAR技术在滑坡监测中的优势及问题点,并结合最新技术进展提出了解决方案,认为应该综合利用先进地球探测及数字处理技术与D-INSAR技术相结合来克服D-INSAR技术中的问题点。具体介绍了永久散射体（PS）技术、小基线子集（SBAS）技术、GPS技术及基于地面的LISA技术等,并对这几种技术与D-INSAR技术的结合进行了探讨,使其达到对滑坡更有效的监测。     

Homogenization of saturated double porous media with Eshelby-like velocity field

In this paper, we focus on strength properties of double porous materials having a Drucker-Prager solid phase at microscale. The porosity consists in two populations of micropores and mesopores saturated with different pressures. To this end, we consider a hollow sphere subjected to a uniform strain rate boundary conditions. For the microscale to mesoscale transition, we take advantage of available results by Maghous et al. (2009), while the meso to macro upscaling is performed by implementing a kinematical limit analysis approach using Eshelby-like trial velocity fields. This two-step homogenization procedure delivers analytical expression of the macroscopic criterion for the considered class of saturated double porous media. This generalizes and improves previous results established by Shen et al. (2014). The results are discussed in terms of the existence or not of effective stresses. Some illustrations are provided.     

Gamma-ray observations from Hinotori

Some interesting results on gamma-ray line emission and its time profiles observed by Hinotori are presented. Possible explanations of gamma-ray line and hard X-ray emissions for the impulsive and gradual flares are discussed. Relationship between the gamma-ray line emission and acceleration and escape of the solar particles is also studied.