550 research outputs found

    El cançoner popular català (1841-1936)

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    New Reports of Exotic and Native Ambrosia and Bark Beetle Species (Coleoptera: Curculionidae: Scolytinae) From Ohio

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    In a 2007 survey of ambrosia and bark beetles (Coleoptera: Curculionidae: Scolytinae) along a transect in northeastern Ohio, we collected six exotic and three native species not previously reported from the state. These species include the exotic ambrosia beetles Ambrosiodmus rubricollis (Eichhoff), Dryoxylon onoharaensum (Murayama), Euwallacea validus (Eichhoff), Xyleborus californicus Wood, Xyleborus pelliculosusEichhoff, and Xylosandrus crassiusculus (Motschulsky). The native ambrosia beetle Corthylus columbianus Hopkins, and the native bark beetles Dryocoetes autographus (Ratzeburg) and Hylastes tenuis Eichhoff are also reported from Ohio for the first time. Our study suggests a northward range expansion for five of the six exotic species including, X. crassiusculus, which is an important pest of nursery and orchard crops in the southeastern United States

    Groundwater characterization of a heterogeneous granitic rock massif for shallow tunneling

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    Shallow tunneling may encounter a number of problems, the most important of which is high water inflows in transmissive areas that are often associated with fractures or discontinuities. Moreover, research into shallow tunneling may be limited by the duration and cost of the civil engineering works. Two important aspects that are often overlooked are: variable groundwater behavior of faults (conduit, barrier, conduit-barrier), and role of groundwater connectivity between fractures that cross the tunnel and the rest of the rock massif. These two aspects should be taken into account in the geological and groundwater characterization to correct the tunnel design and minimize hazards. A geological study and a preliminary hydrogeological characterization (including a prior steady state investigation and cross bore-hole tests) were carried out in a granitic sector during the construction of Line 9 of the Barcelona subway (B-20 area). The hydrogeological conceptual model was constructed using a quasi-3D numerical model, and different scenarios were calibrated. Faults and dikes show a conduit-barrier behavior, which partially compartmentalized the groundwater flow. The barrier behavior, which is the most marked effect, is more prominent in faults, whereas conduit behavior is more notable in dikes. The characterization of groundwater media entailed a dewatering plan and changes in the tunnel course. This enabled us to construct the tunnel without any problems

    Significació etnomusicològica del professor Josep Crivillé i Bargalló (*1947; †2012). (Rellegir alguns dels seus textos des del record)

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    From different significant lectures of the Prof. Josep Crivillé i Bargalló, the author proposes his professional and personal profile in the subject of Ethnomusicology.A través de diferentes textos significativos del prof. Josep Crivillé i Bargalló, el autor pone de relieve la trayectoria profesional y personal de dicho profesor en el terreno de la Etnomusicología. [ca] Mitjançant diversos textos significatius del prof. Josep Crivillé i Bargalló, l’autor posa de relleu la trajectòria professional i personal de l’esmentat professor en l’àmbit de la Etnomusicologia

    La comarca del Bages i l'obra del Cançoner Popular de Catalunya

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    Induced seismicity in pressurised single fractures: a numerical approach

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    The exploration and exploitation of deep geothermal reservoirs has significantly increased during the last years. These reservoirs use heat exchange to produce heat or electricity. The so-called Enhanced Geothermal Systems (EGS) are characterized by a stimulation phase that aims to increase fluid flow and heat transfer between wells by increasing the permeability and transitivity of the reservoir. This is achieved by injecting high-pressure fluids (normally water) in order to increase the apertures of existing fractures, enhancing their sliding and/or generating new ones. However, this technique induces low-magnitude seismicity that occasionally results in damage at the Earth's surface. Numerical simulations able to reproduce the hydro-thermo-mechanical behaviour of geological reservoirs are an essential tool for the evaluation and forecasting of induced seismicity in such systems. In this study, the numerical code CFRAC is used to systematically evaluate how the orientation of faults with respect to the stress field influences seismicity, the injection rate and the fracture sliding behaviour
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