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Building on evidence starting from 1966, X-ray observations have once again confirmed the association of quasars with low redshift galaxies. Enough examples of quasar-like objects ejected in opposite directions from nearby, active galaxies have accumulated so that an empirical evolutionary sequence can be outlined. The quasars start out with low luminosity and high (z > 2) redshift. As they travel away from their galaxy of origin they grow in size and decay in redshift. The redshifts drop in steps and near the quantized values of z = 0.6, 0.3, and 0.06 the quasars become particularly active, ejecting or breaking up into many objects which evolve finally into groups and clusters of galaxies. The observations massively violate the assumptions of the Big Bang and require continuous, episodic creation in a non expanding universe of indefinitely large size and age.  相似文献   
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A Kalman filter-based method combining the energy of both L1 C/A and L2C GPS signals in a combined tracking loop method to enhance performance under adverse conditions is developed. Standard tracking methods and the ionospheric effect on GPS signals are reviewed and compared to a new Kalman filter that simultaneously estimates delay, phase and total electron content by combining L1 C/A and L2C code and phase discriminator outputs. The new filter is tested and compared to standard methods for tracking L1 C/A and L2C using both simulated and real data. The new method is found to have improved sensitivity of 3 dB compared to standard L1 tracking and 4.5 dB compared to standard L2C tracking while at the same time providing an accurate estimate of the total electron content along the signal path.  相似文献   
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This article summarizes trends in total Hg concentrations (THg) in fungal fruiting bodies (basidiomata) and their underlying soil substrates in the absence and presence of surrounding moss layers. Three forest locations across south-western New Brunswick spanning from a central mainland location to Grand Manan Island in the Bay of Fundy were chosen for the study. Geographic location had an effect on THg in the soil layers and in the basidiomata (THg on island > THg along the mainland coast > THg mainland) but this effect was weak and probably obscured by the large THg variations within the basidiomata and their soil and moss substrates at each location. Within the soil, THg increased with increasing total organic S (TS) and C (TC) concentrations, and depended on type of moss cover if present. Within the mosses, THg varied by species, by moss-internal TS, and by THg and TS within the underlying soil. Basidiomatal THg also varied strongly by species, and was further affected by: (i) developmental stage, from emergence to senescence, (ii) cap versus stalk, (iii) basidiomatal TS, and (iv) soil THg, TS and TC. These variations and their interdependencies were explored and quantified by way of multiple regression analyses. Basidiomatal bioconcentration of soil THg (F layer) varied strongly by species as well. Basidiomatal Hg extraction from the soil was estimated to be small in terms of reducing the accumulated Hg loads within the soil, but represents a re-entry point of Hg into the local food chain.  相似文献   
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We have carried out a series of in situ experiments to investigate the formation of a CO2 hydrate (CO2:5.75 H2O) for the purpose of evaluating scenarios for ocean fossil fuel CO2 disposal with a solid hydrate as the sequestered form. The experiments were carried out with a remotely operated vehicle in Monterey Bay at a depth of 619 m. pH measurements made in close proximity to the hydrate–seawater interface showed a wide range of values, depending upon the method of injection and the surface area of the hydrate formed. Rapid injection of liquid CO2 into an inverted beaker to form a flocculant mass of hydrate resulted in pH initially as low as 4.5 within a few centimeters of the interface, decaying slowly over 1–2 h towards normal seawater values as dense CO2 rich brine drained from the hydrate mass. In a second experiment, slower injection of the liquid CO2 to produce a simple two-layer system with a near planar interface of liquid CO2 with a thin hydrate film yielded pH values indistinguishable from the in situ ocean background level of 7.6. Both field and laboratory results now show that the dissolution rate of a mass of CO2 hydrate in seawater is slow but finite.  相似文献   
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Image processing performed on a series of photographs of the superluminal Seyfert galaxy, 3C 120, shows the outer optical disc to consist of fragmented segments generally pointing toward the centre. One long arm of peculiar, separated knots comes off to the W and SW. A peculiar companion is seen along the line of the NW radio jet. In the interior, optical jets are detected which are aligned along the direction of the outer radio jets. A region of the sky 45 ×; 25 degrees around 3C120 is investigated. It is found that:
  1. A nebulous filament about 3/4 degree in length points to 3C 120.
  2. Hydrogen clouds of redshiftz = ?130 and ?210 km s?1 are situated at 3 and 1 degrees on either side of 3C 120.
  3. Eleven low-surface-brightness galaxies with 4500 <z < 5300 km s?1 fall within a radius of 8 degrees.
  4. Seven quasars withz ? 1.35 and radio fluxesS b ? 0.3 fall within a radius of 10 degrees.
It is concluded that the concentration of these objects in the vicinity of this unique, active galaxy has a negligible chance of being accidental and that all those objects of diverse redshift are at the same nearby distance. This smaller distance reduces the supposed superluminal motions in 3C 120 to quite precedented ejection velocities.  相似文献   
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