23,547 research outputs found

    A Primer for Monitoring Water Funds

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    This document is intended to assist people working on Water Funds to understand their information needs and become familiar with the strengths and weaknesses of various monitoring approaches. This primer is not intended to make people monitoring experts, but rather to help them become familiar with and conversant in the major issues so they can communicate effectively with experts to design a scientifically defensible monitoring program.The document highlights the critical information needs common to Water Fund projects and summarizes issues and steps to address in developing a Water Fund monitoring program. It explains key concepts and challenges; suggests monitoring parameters and an array of sampling designs to consider as a starting-point; and provides suggestions for further reading, links to helpful resources,and an annotated bibliography of studies on the impacts that result from activities commonly implemented in Water Fund projects

    Wave packet dynamics of potassium dimers attached to helium nanodroplets

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    The dynamics of vibrational wave packets excited in K2_2 dimers attached to superfluid helium nanodroplets is investigated by means of femtosecond pump-probe spectroscopy. The employed resonant three-photon-ionization scheme is studied in a wide wavelength range and different pathways leading to K2+^+_2-formation are identified. While the wave packet dynamics of the electronic ground state is not influenced by the helium environment, perturbations of the electronically excited states are observed. The latter reveal a strong time dependence on the timescale 3-8 ps which directly reflects the dynamics of desorption of K2_2 off the helium droplets

    Coolant passage heat transfer with rotation

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    The objective is to develop a heat transfer and pressure drop data base, computational fluid dynamic techniques, and correlations for multi-pass rotating coolant passages with and without flow turbulators. The experimental effort is focused on the simulation of configurations and conditions expected in the blades of advanced aircraft high pressure turbines. With the use of this data base, the effects of Coriolis and buoyancy forces on the coolant side flow can be included in the design of turbine blades

    Spectroscopy of Rb2_{2} dimers in solid 4^{4}He

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    We present experimental and theoretical studies of the absorption, emission and photodissociation spectra of Rb2_{2} molecules in solid helium. We have identified 11 absorption bands of Rb2_{2}. All laser-excited molecular states are quenched by the interaction with the He matrix. The quenching results in efficient population of a metastable (1)3Πu^{3}\Pi_{u} state, which emits fluorescence at 1042 nm. In order to explain the fluorescence at the forbidden transition and its time dependence we propose a new molecular exciplex Rb2(3Πu)_{2}(^{3}\Pi_{u})He2_{2}. We have also found evidence for the formation of diatomic bubble states following photodissociation of Rb2_{2}

    The International Veterinary Student Association (I.V.S.A.)

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    We don\u27t have to look very far in this world to see immense trouble and distress between peoples and races. In my own country, for example, we have the Northern Ireland situation - ever present however blind we pretend our eyes to be, This conflict is only one of a profoundly shattering list of clashes between sections of humanity. There is a trend of thought which dismisses such problems as human nature . Such believers feel that strife will always prevail whatever attempts are made to promote international harmony. I am no philosopher but I do not hold with this belief

    Metastable states of a flux line lattice studied by transport and Small Angle Neutron Scattering

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    Flux Lines Lattice (FLL) states have been studied using transport measurements and Small Angle Neutron Scattering in low Tc_c materials. In Pb-In, the bulk dislocations in the FLL do not influence the transport properties. In Fe doped NbSe2_{2}, transport properties can differ after a Field Cooling (FC) or a Zero Field Cooling (ZFC) procedure, as previously reported. The ZFC FLL is found ordered with narrow Bragg Peaks and is linked to a linear V(I) curve and to a superficial critical current. The FC FLL pattern exhibits two Bragg peaks and the corresponding V(I) curve shows a S-shape. This can be explained by the coexistence of two ordered FLL slightly tilted from the applied field direction by different superficial currents. These currents are wiped out when the transport current is increased.Comment: accepted for publication in Phys. Rev.
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