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Although large amounts of data have been collected at The Geysers, some reservoir parameters, such as initial liquid saturation, matrix permeability and the fracture network characteristics, are still poorly known. These parameters greatly affect results of resource evaluation and predictions of reservoir behavior. Several two-dimensional fractured porous medium models have been developed for The Geysers; these models differ in assumptions regarding the initial liquid saturation and matrix permeabilities. These models indicate that the permeability-thickness product (kH) of the fracture network ranges from 10 to 75 Dm (30,000 to 225,000 md{center dot}ft) and matrix permeability ranges from 1 to 3 {mu}Darcies ({mu}D). All three models yielded surprisingly similar predictions regarding the future generating capacities of different areas. 17 refs., 6 figs.

LBL-787~ d-- RECEIVE[) LAWHENCE f:lERI

The first series of experiments of the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] tested ignition Hohlraum “energetics,” a term described by four broad goals: (1) measurement of laser absorption by the Hohlraum; (2) measurement of the x-ray radiation flux (TRAD4) on the surrogate ignition capsule; (3) quantitative understanding of the laser absorption and resultant x-ray flux; and (4) determining whether initial Hohlraum performance is consistent with requirements for ignition. This paper summarizes the status of NIF Hohlraum energetics experiments. The Hohlraum targets and experimental design are described, as well as the results of the initial experiments. The data demonstrate low backscattered energy (<10%) for Hohlraums filled with helium gas. A discussion of our current understanding of NIF Hohlraum x-ray drive follows, including an overview of the computational tools, i.e., radiation-hydrodynamics codes that have been used to design the Hohlraums. The performance of the codes is compared to x-ray drive and capsule implosion data from the first NIF experiments. These results bode well for future NIF ignition Hohlraum experiments.

The cost of structural components in a large superconducting coil such as SMES may well exceed the coil and cryostat cost. As a result, the idea of constructing a system composed of two different coil types assembled in such a way that the forces balance and reduce the total structural requirement is often proposed. A suitable geometry has never been found for the fundamental reason that there can be no force-compensated solution. The general problem is presented, and an analysis of the energy stored and stresses produced in the structure is described in a fundamental way. Finally, relation between structural mass M and stored energy E that is valid for all magnetic systems is developed. >

Summary form only given, as follows. The Los Alamos foil implosion program has the goal of producing an intense high-energy density X-ray source by converting the energy of a magnetically imploded plasma into radiation and material energy. One of the methods for converting the kinetic energy of the plasma into thermal energy and radiation and utilizing it for experiments is called the "flying radiation case (FRC)." In this paper we shall model the FRC and provide a physical description of the processes involved.

Abstract In-situ electrical resistivity damage-rate measurements in the high voltage electron microscope have been used to study electron irradiation induced defect production in copper single crystals at T . Analysis of the directional and energy dependence yields a threshold energy surface that is significantly different from those of previous investigations: two pockets of low threshold energy centered at 〈100〉 and 〈110〉 surrounded by regions of much higher threshold energy. The corresponding damage function exhibits a plateau at 0.6 Frenkel pairs. The present results imply a Frenkel pair resistivity for Cu of (2.75 +0.6−0.2) × 10−4 Ω cm.

During acceptance testing of the Mirror Fusion Test Facility (MFTF), we measured these tests: liquid helium heat loads and flow rates in selected magnets. We used the data from these tests to estimate helium vapor quality in the magnets so that we could determine if adequate conductor cooling conditions had occurred. We compared the measured quality and flow with estimates from a theoretical model developed for the MFTF magnets. The comparison is reasonably good, considering influences that can greatly affect these values. This paper describes the methods employed in making the measurements and developing the theoretical estimates. It also describes the helium system that maintained the magnets at required operating conditions.

Combined data of photoelectron spectra and photoionization efficiency curves in the near threshold ionization region of isolated ion pairs from [emim][Tf(2)N], [emim][Pf(2)N], and [dmpim][Tf(2)N] ionic liquid vapors reveal small shifts in the ionization energies of ion-pair systems due to cation and anion substitutions. Shifts toward higher binding energy following anion substitution are attributed to increased electronegativity of the anion itself, whereas shifts toward lower binding energies following cation substitution are attributed to an increase in the cation-anion distance that causes a lower Coulombic binding potential. The predominant ionization mechanism in the near threshold photon energy region is identified as dissociative ionization, involving the dissociation of the ion pair and the production of intact cations as the positively charged products.