Tube joint leak repair coupling

Tube joint leak repair coupling consists of 2 split seals, 1 male split nut, 1 female split nut, and two aligning pins. Each split nut consists of 2 half-shell sections which, when engaged, are held together by a dovetail joint and an aligning pin

Experimental determination of residual stress

Residual stresses in finished parts have often been regarded as factors contributing to premature part failure and geometric distortions. Currently, residual stresses in welded structures and railroad components are being investigated. High residual stresses formed in welded structures due primarily to the differential contractions of the weld material as it cools and solidifies can have a profound effect on the surface performance of the structure. In railroad wheels, repeated use of the brakes causes high residual stresses in the rims which may lead to wheel failure and possible derailment. The goals of the study were: (1) to develop strategies for using x-ray diffraction to measure residual stress; (2) to subject samples of Inconel 718 to various mechanical and heat treatments and to measure the resulting stress using x-ray diffraction; and (3) to measure residual stresses in ferromagnetic alloys using magnetoacoustics

Recessions and recoveries associated with asset-price movements: what do we know? : a speech at the Stanford Institute for Economic Policy Research, Stanford, California, January 12, 2005, and the Real Estate Roundtable, Washington, D.C., January 27, 2005

Asset pricing ; Recessions

Miniature sonar fish tag

Self-powered sonar device may be implanted in body of fish. It transmits signal that can be detected with portable tracking gear or by automatic detection-and-tracking system. Operating life of over 4000 hours may be expected. Device itself may be used almost indefinitely

General discussion : understanding the Greenspan standard

Greenspan, Alan ; Monetary policy ; Business cycles ; Economic conditions

Optically Thin Core Accretion: How Planets Get Their Gas in Nearly Gas-Free Disks

Models of core accretion assume that in the radiative zones of accreting gas envelopes, radiation diffuses. But super-Earths/sub-Neptunes (1-4$R_\oplus$, 2-20$M_\oplus$) point to formation conditions that are optically thin: their modest gas masses are accreted from short-lived and gas-poor nebulae reminiscent of the transparent cavities of transitional disks. Planetary atmospheres born in such environments can be optically thin to both incident starlight and internally generated thermal radiation. We construct time-dependent models of such atmospheres, showing that super-Earths/sub-Neptunes can accrete their $\sim$1%-by-mass gas envelopes, and super-puffs/sub-Saturns their $\sim$20%-by-mass envelopes, over a wide range of nebular depletion histories requiring no fine tuning. Although nascent atmospheres can exhibit stratospheric temperature inversions effected by atomic Fe and various oxides that absorb strongly at visible wavelengths, the rate of gas accretion remains controlled by the radiative-convective boundary (rcb) at much greater pressures. For dusty envelopes, the temperature at the rcb $T_{\rm rcb} \simeq 2500$ K is still set by ${\rm H}_2$ dissociation; for dust-depleted envelopes, $T_{\rm rcb}$ tracks the temperature of the visible or thermal photosphere, whichever is deeper, out to at least $\sim$5 AU. The rate of envelope growth remains largely unchanged between the old radiative diffusion models and the new optically thin models, reinforcing how robustly super-Earths form as part of the endgame chapter in disk evolution.Comment: accepted to MNRAS, new section 4.2 connects our formation scenario of super-Earths to atmospheric mass los

A (13)C NMR analysis of the effects of electron radiation on graphite/polyetherimide composites

Initial investigations have been made into the use of high resolution nuclear magnetic resonance (NMR) for the characterization of radiation effects in graphite and Kevlar fibers, polymers, and the fiber/matrix interface in graphite/polyetherimide composites. Sample preparation techniques were refined. Essential equipment has been procured. A new NMR probe was constructed to increase the proton signal-to-noise ratio. Problem areas have been identified and plans developed to resolve them

Understanding financial consolidation

Keynote address for a conference sponsored by the Federal Reserve Bank of New York entitled Financial Innovation and Monetary TransmissionFinancial modernization ; Bank mergers

Formal Context Generation using Dirichlet Distributions

We suggest an improved way to randomly generate formal contexts based on Dirichlet distributions. For this purpose we investigate the predominant way to generate formal contexts, a coin-tossing model, recapitulate some of its shortcomings and examine its stochastic model. Building up on this we propose our Dirichlet model and develop an algorithm employing this idea. By comparing our generation model to a coin-tossing model we show that our approach is a significant improvement with respect to the variety of contexts generated. Finally, we outline a possible application in null model generation for formal contexts.Comment: 16 pages, 7 figure