Oak Ridge National Laboratory

About: Oak Ridge National Laboratory is a facility organization based out in Oak Ridge, Tennessee, United States. It is known for research contribution in the topics: Neutron & Ion. The organization has 31868 authors who have published 73724 publications receiving 2633689 citations. The organization is also known as: ORNL.

“Lithium‐Free” Thin‐Film Battery with In Situ Plated Li Anode

Abstract: The "Li‐free" thin‐film battery with the cell configuration Li diffusion blocking overlayer/Cu/solid lithium electrolyte is activated by in situ plating of metallic Li at the Cu anode current collector during the initial charge. Electrochemical cycling between 4.2 and 3.0 V is demonstrated over 1000 cycles at or over 500 cycles at . As corroborated by scanning electron microscopy during electrochemical cycling, the overlayer is imperative for a high cycle stability; otherwise the plated Li rapidly develops a detrimental morphology, and the battery loses most of its capacity within a few cycles. The Li‐free thin‐film battery retains the high potential of a Li cell while permitting its fabrication in air without the complications of a metallic Li anode. Thus, the Li‐free thin‐film battery survives solder reflow conditions, simulated by a rapid heating to 250°C for 10 min in air followed by quenching to room temperature, without any signs of degradation. © 2000 The Electrochemical Society. All rights reserved.

Atmospheric Chemistry and Physics of Air Pollution

Abstract: This is a n ambitious book on a complex subject, written by an expert in the field. It is aimed at graduate students and above, perhaps including upper-level undergraduates, and subjects treated are accordingly many, diverse, and intricately interwoven. It could easily have failed on any one of a number of counts, and it is a distinct pleasure to report that, as far as this reviewer is concerned, it did not. The reader of this book gets a detailed, logically organized discussion of air pollution chemistry and physics, in which few concessions have been made to the real difficulties of the subject matter and none to clarity of presentation. The text material is divided into six parts: pollutants — sources and effects; air pollution chemistry; aerosols; air pollution-meteorology; atmospheric diffusion; and a special topics section in which the important subjects of air pollution statistics and acid rain are discussed.

Fluctuations and anomalous transport in tokamaks

Abstract: This is a review of what is known about fluctuations and anomalous transport processes in tokamaks. It mostly considers experimental results obtained after, and not included in, the reviews of Liewer [Nucl. Fusion 25, 543 (1985)], Robinson [in Turbulence and Anomalous Transport in Magnetized Plasmas (Ecole Polytechnique, Palaiseau, France, 1986), p. 21], and Surko [in Turbulence and Anomalous Transport in Magnetized Plasmas (Ecole Polytechnique, Palaiseau, France, 1986), p. 93]. Therefore much of the pioneering work in the field is not covered. Emphasis is placed on results where comparisons between fluctuations and transport properties have been attempted, particularly from the tokamak TEXT [Nucl. Technol./Fusion 1, 479 (1981)]. A brief comparison of experimentally measured total fluxes with the predictions of neoclassical theory demonstrates that transport is often anomalous; fluctuations are thought to be the cause.The measurements necessary to determine any such fluctuation‐driven fluxes are described. The diagnostics used to measure these quantities, together with some of the statistical techniques employed to analyze the data, are outlined. In the plasma edge detailed measurements of the quantities required to directly determine the fluctuation‐driven fluxes are available. The total and fluctuation‐driven fluxes are compared: the result emphasizes the importance of edge turbulence. No model adequately describes all the measured properties. In the confinement region experimental observations are presently restricted to measurements of density and potential fluctuations and their correlations. Various distinct turbulence features that have been observed are described, and their characteristics compared with the predictions of various models. Correlations observed between these fluctuations and plasma transport properties are summarized. A separate section on magnetic fluctuations shows there is very little information available inside the plasma, generally prohibiting quantified comparisons between fluctuation levels and transport. Both coherent and turbulent magnetic fluctuations are addressed, and the differences between low and high plasma pressure (low and high beta) are noted. The contributions of alternate confinement devices, such as stellarators and reversed field pinches, to understanding tokamak anomalous transport are discussed. Finally, future directions are proposed.

Fused filament fabrication of fiber-reinforced polymers: A review

Abstract: Recent advancements in the Additive Manufacturing (AM) Fused Filament Fabrication (FFF) approach are described with focus on the application to tooling and molds for composite materials and structures. A detailed summary of mechanical properties of printed parts for different composite material systems is presented and discussed. These material systems are comprised of discontinuous fiber-reinforced polymers characterized by fiber orientation dominantly parallel to the direction of the extrudate. An overview of the FFF process and its physical phenomena is given including the flow and resulting fiber orientation, the bond formation between adjacent beads and the thermomechanical solidification behavior of the deposited material. Based on reviewed research in these different phenomena, future research needs are discussed and desirable objectives are formulated.

Minimum Thermal Conductivity of Superlattices

Abstract: The phonon thermal conductivity of a multilayer is calculated for transport perpendicular to the layers. There is a crossover between particle transport for thick layers to wave transport for thin layers. The calculations show that the conductivity has a minimum value for a layer thickness somewhat smaller then the mean free path of the phonons.