Quantum adaptation of noisy channels

Probabilistic quantum filtering is proposed to properly adapt sequential independent quantum channels in order to stop sudden death of entanglement. In the adaptation, the quantum filtering does not distill or purify more entanglement, it rather properly prepares entangled state to the subsequent quantum channel. For example, the quantum adaptation probabilistically eliminates the sudden death of entanglement of two-qubit entangled state with isotropic noise injected into separate amplitude damping channels. The result has a direct application in quantum key distribution through noisy channels.Comment: 6 pages, 4 figure

Hawaiian Quaternary Paleoenvironments: A Review of Geological, Pedological, and Botanical Evidence.

Climates in Hawaii during glacial periods were relatively wetter and cooler than interglacial climates. Eolian deposits indicate that northeasterly trade winds predominated during glacial periods. Orographic rainfall patterns were probably similar to those of today except that they were shifted downward in response to lowered sea levels and a depressed inversion level. Botanical evidence indicates that some areas probably received more than double their current annual rainfall. Greater rainfall during glacial periods was probably responsible for the formation of highly weathered soils that are now in semiarid climates. More intense periglacial processes may have operated during glacial periods. Snowline on Mauna Kea was depressed about 900 m and glaciation may have occurred because of lower air temperature and greater cloudiness. Ocean temperature was probably also slightly cooler. At low elevations, interglacial climates were drier than glacial climates because of the influence higher sea levels had on orographic rainfall distribution. Trade winds still predominated but the inversion level was higher, which may have caused greater rainfall at high elevations. Pedological evidence indicates a highly erosive environment before the formation of the Kaena shoreline at about 650,000 yr ago. Climatic conditions at that time are not known. Subsequent environmental conditions have not been as conducive to erosion, and the past several hundred thousand years have witnessed relative landscape stability

ii Effects of Thermal Aging on Fracture Toughness and Charpy–Impact Strength of Stainless Steel Pipe Welds by

The degradation of fracture toughness, tensile, and Charpy–impact properties of Type 308 stainless steel (SS) pipe welds due to thermal aging has been characterized at room temperature and 290°C. Thermal aging of SS welds results in moderate decreases in Charpy–impact strength and fracture toughness. For the various welds in this study, upper–shelf energy decreased by 50–80 J/cm 2. The decrease in fracture toughness J–R curve or JIC is relatively small. Thermal aging had little or no effect on the tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second–phase particles. Failure occurs by the formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on the fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical–property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds

Effects of thermal aging on fracture toughness and Charpy-impact strength of stainless steel pipe welds

Degradation of fracture toughness, tensile, and Charpy-impact properties of Type 304 and 304/308 SS pipe welds due to thermal aging was studied at room temperature and 290 C. Thermal aging of SS welds results in moderate decreases in charpy-impact strength and fracture toughness. Upper-shelf energy decreased by 50-80 J/cm{sup 2}. Decrease in fracture toughness J-R curve or J{sub IC} is relatively small. Thermal aging had no or little effect on tensile strength of the welds. Fracture properties of SS welds are controlled by the distribution and morphology of second-phase particles. Failure occurs by formation and growth of microvoids near hard inclusions; such processes are relatively insensitive to thermal aging. The ferrite phase has little or no effect on fracture properties of the welds. Differences in fracture resistance of the welds arise from differences in the density and size of inclusions. Mechanical-property data from the present study are consistent with results from other investigations. The existing data have been used to establish minimum expected fracture properties for SS welds

Environmentally assisted cracking in Light Water Reactors: Semiannual report, October 1994--March 1995. Volume 20

This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRS) from October 1994 to March 1995. Topics that have been investigated include (a) fatigue of carbon and low-alloy steel used in reactor piping and pressure vessels, (b) EAC of Alloy 600 and 690, and (c) irradiation-assisted stress corrosion cracking (IASCC) of Type 304 SS. Fatigue tests were conducted on ferritic steels in water with several dissolvedoxygen (DO) concentrations to determine whether a slow strain rate applied during different portions of a tensile-loading cycle are equally effective in decreasing fatigue life. Tensile properties and microstructures of several heats of Alloy 600 and 690 were characterized for correlation with EAC of the alloys in simulated LWR environments. Effects of DO and electrochemical potential on susceptibility to intergranular cracking of high- and commercial-purity Type 304 SS specimens from control-blade absorber tubes and a control-blade sheath irradiated in boiling water reactors were determined in slow-strain-rate-tensile tests at 289{degrees}C. Microchemical changes in the specimens were studied by Auger electron spectroscopy and scanning electron microscopy to determine whether trace impurity elements may contribute to IASCC of these materials

Using terahertz spectroscopy for observing the kinetics of recrystallisation of polybutene-1

This paper deals with the use of terahertz spectroscopy for observing the kinetics of recrystallisation of polybutene-1 as a suitable material for manufacturing optical elements in the terahertz region of the electromagnetic spectrum. These materials were studied from the perspective of their optical properties - the refractive index and the absorption coefficient. The time dependencies of the refractive index and the absorption coefficient were measured, because polybutene-1 is a material which recrystallises for a number of days from the date of its manufacture. The coefficients describing the recrystallisation process were calculated from the fitting function derived from the Avrami equation. In this paper, the measurement results are presented and the possibilities of the use of the studied materials are discussed