An elastoviscoplastic constitutive model for geomaterials: Application to hydromechanical modelling of claystone response to drift excavation

An isotropic elastoviscoplastic constitutive model based on a generalized Hoek-Brown criterion is proposed. The plastic mechanism is characterized by a positive and a negative hardening, and a specific non-associated flow rule allows to take into account the evolution of the dilatancy. Several hydromechanical finite element simulations corresponding to realistic configurations of drift excavations in the underground research laboratory of Bure are presented. Regularization techniques are required to avoid localization phenomena due to softening. A second gradient formulation has been used as it is well suited for dilatant materials such as claystone. Numerical results are discussed and compared with experimental measurements.     

PPGIS及其在加拿大安大略省核废料处理选址项目中的应用

介绍了公众参与地理信息系统，给出了一个应用项目——加拿大安大略省核废料处理设施选址公众参与地理信息系统。     

直接寻找油气田的土壤综合物性勘探方法技术

主要论述了用于直接寻找油气田的土壤综合物性勘探的机理和方法技术,包括土壤磁性（磁化率、天然剩磁、原生剩磁）、电性（电导率、氧化还原电位）、放射性等综合参数的利用。该方法成本低廉、野外施工简单、快捷,物性参数可在野外和实验室测定,属无源和非破坏性的勘探技术,为直接寻找油气田提供了一种新的思路和新的方法技术。     

Deterministic sensitivity analysis for a model for flow in porous media

A deterministic method for sensitivity analysis is developed and applied to a mathematical model for the simulation of flow in porous media. The method is based on the singular value decomposition (SVD) of the Jacobian matrix of the model. It is a local approach to sensitivity analysis providing a hierarchical classification of the directions in both the input space and of those in the output space reflecting the degree of sensitiveness of the latter to the former. Its low computational cost, in comparison with that of statistical approaches, allows the study of the variability of the results of the sensitivity analysis due to the variations of the input parameters of the model, and thus it can provide a quality criterion for the validity of more classical probabilistic global approaches. For the example treated here, however, this variability is weak, and deterministic and statistical methods yield similar sensitivity results.     

高放废物地质处置北山预选区旧井和新场花岗岩填隙方解石同位素地球化学

为了探讨高放废物地质处置甘肃北山预选区旧井和新场预选地段的古地下流体来源、成因、化学演化历史以及水-岩相互作用,文章系统研究了该地段花岗岩填隙方解石的产出特征及其碳、氧、锶同位素的组成特征。测试结果表明,旧井和新场方解石的δ13 C组成均较稳定且为负值(分别为-11.6‰~-5.7‰和-9.9‰~-5.1‰);δ18 O分别为-0.7‰~19.7‰和10.9‰~21.9‰,旧井方解石具有更宽的δ18 O取值范围。87 Sr/86 Sr也略有差异,旧井为0.708584~0.718749,新场为0.708838~0.732967,二者随深度增加而呈明显的降低趋势。研究表明,北山预选区地下流体来源及成因较复杂,浅部地下水受大气降水的影响较大,深部流体则主要源于地下咸水,为低温流体蚀变成因。花岗岩裂隙中的水-岩反应强度总体较弱,地下水环境相对稳定。相比较而言,新场岩体深部的地球化学环境更稳定,更有利于高放废物的长期处置。     

From “cartoneros” to “recolectores urbanos”. The changing rhetoric and urban waste management policies in neoliberal Buenos Aires

This study contributes to the existent literature on neoliberal urban governance examining the process-based character of this formation. I maintain that neoliberal governance is a fluid and evolving formation which is continuously being constructed and reconstructed beneath a rhetorical veneer of inevitable emergence and permanence. In this context, this work examines the interconnections between neoliberal urban ascendancy, changing rhetoric and urban waste management policies, and waste pickers (cartoneros), in a case study setting, Buenos Aires. Since 2002, the neoliberal urban governance in Buenos Aires (its institutions, programs and policies) has mobilized different rhetoric and policies to negotiate the waste pickers’ “disturbing” and “dirty” presence in the streets. In that process, the waste pickers, originally marginalized and stigmatized by the neoliberal discourse, have been regulated and disciplined into legal and “well behaved” workers. I would argue that, regulating this activity does not entail giving the waste pickers an opportunity to become central actors in the future of urban waste management in the city. Rather, it is compatible with the logic of the local neoliberal urban projects, focused on disciplining the city’s physical and social landscape as new opportunities for growth and development continue to emerge.     

放射性勘探探寻油气藏的试验效果

对应用放射性直接探寻油气藏勘探试验所取得已知油藏区的资料进行了综合分析。总结了油气藏上方放射性异常的规律;探讨了放射性异常与油气藏的关系。对放射性异常的数据处理方法及应用放射性方法探寻油气藏的应用效果进行了剖析。指出:在实际应用中,氡浓度测量在勘查油气藏方面比伽玛能谱总量和伽玛能谱具有较好的应用效果。     

The Seashell Wastes as Biosorbent for Reactive Dye Removal from Textile Effluents

This study investigates structural and adsorption properties of the powdered waste shells of Rapana gastropod and their use as a new cheap adsorbent to remove reactive dye Brilliant Red HE‐3B from aqueous solutions under batch conditions. For the powder shells characterization, solubility tests in acidic solutions and X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), Fourier transform IR spectroscopy (FT‐IR) and thermogravimetric analyses were performed. The results revealed that the adsorbent surface is heterogeneous consisting mainly from calcium carbonate layers (either calcite or aragonite) and a small amount of organic macromolecules (proteins and polysaccharides). The dye adsorptive potential of gastropod shells powder was evaluated as function of initial solution pH (1–5), adsorbent dose (6–40 g L^?1), dye concentration (50–300 mg L^?1), temperature (5–60°C), and contact time (0–24 h). It was observed that the maximum values of dye percentage removal were obtained at the initial pH of solution 1.2, shells dose of 40 g L^?1, dye initial concentration of 50–50 mg L^?1 and higher temperatures; the equilibrium time decreases with increasing of dye concentration. It is proved that the waste seashell powder can be used as low cost bioinorganic adsorbent for dyes removal from textile wastewaters.     

城市固体废弃物填埋场的岩土工程问题

论述了国内外城市卫生填埋场相关的岩土工程问题及其研究现状,包括卫生填埋场填埋体物理力学性质、卫生填埋场的防渗系统和边坡稳定等一系列岩土工程问题,在此基础上初步探讨了我国城市卫生填埋场相关岩土工程问题的发展前景。