2,675 research outputs found
Feed-thru conduit minimizes heat pickup
Insulated feed-thru conduit minimizes heat pickup by a cryogenic fluid passing through the walls of a double high-vacuum chamber, and is capable of expansion and contraction with the walls of the chamber. It uses a bellows and rigid cylinder to provide a low-loss feed-thru for the cryogenic liquid
Feed-thru flange is useful in vacuum applications to cryogenic temperatures
Feed-thru flange seals inner and outer walls of high vacuum test chambers. It is used in vacuum applications at both cryogenic and higher than cryogenic temperatures. A damaged flange can still be used for partial vacuum, noncryogenic applications in conjunction with an appropriate rubber seal
Combination double door high-vacuum valve provides access to vacuum chamber
Double door provides an extreme high vacuum seal as well as access to a vacuum chamber for insertion of test devices into the vacuum environment. This arrangement is applicable to any vacuum chamber and could be of value in cryopumping or mechanically pumped chambers
Piping arrangement through a double chamber structure
Low thermal loss piping arrangement for moving cryogenic media through double chamber structur
Ultra-high molecular sink vacuum chamber
Double-wall vacuum chamber can be separated from the remainder of the system and pumped by ultra-clean techniques. Ultrahigh vacuum is maintained by the cryogenic effect of a cold wall and titanium chemisorption
Adaptive defuzzification for fuzzy systems modeling
We propose a new parameterized method for the defuzzification process based on the simple M-SLIDE transformation. We develop a computationally efficient algorithm for learning the relevant parameter as well as providing a computationally simple scheme for doing the defuzzification step in the fuzzy logic controllers. The M-SLIDE method results in a particularly simple linear form of the algorithm for learning the parameter which can be used both off- and on-line
Elastic precursor of the transformation from glycolipid-nanotube to -vesicle
By the combination of optical tweezer manipulation and digital video
microscopy, the flexural rigidity of single glycolipid "nano" tubes has been
measured below the transition temperature at which the lipid tubules are
transformed into vesicles. Consequently, we have found a clear reduction of the
rigidity obviously before the transition as temperature increasing. Further
experiments of infrared spectroscopy (FT-IR) and differential scanning
calorimetry (DSC) have suggested a microscopic change of the tube walls,
synchronizing with the precursory softening of the nanotubes.Comment: 9 pages, 6 figure
Nitrogen Transport in a Shallow Outwash Aquifer at Olean, Cattaraugus County, New York
Groundwater beneath an industrial park at Olean, New York, contained nitrogen compounds in concentrations that in 1983 ranged from 10 to 1,280 mg/L as nitrogen, mainly in the form of ammonium. Continuous pumping from an industrial well field creates a cone of depression that prevents the nitrogen compounds from migrating to municipal-supply wells, 7,000 ft away. A two-dimensional solute transport model was used to simulate changes in nitrogen concentrations that would result from a permanent shutdown of the well field. The model assumed the nitrogen source decayed at an exponential rate with a decay constant of 0.3/year to account for nitrogen removed from the aquifer by pumping during 1978-84. The source of contamination was found to be sensitive to the volume of pumpage at the industrial well field, which altered the rate of groundwater flow through the contaminated area. Simulations of a permanent shutdown of the well field, assuming nitrogen migrates as a conservative solute, indicated that nitrogen-bearing groundwater would reach the municipal well field within 5 years and the peak concentrations at the municipal well field would range from 2 to 5 mg/L. Simulations of Langmuir adsorption of the dissolved ammonium with a one-dimensional model indicated that the arrival of the solute front at the municipal well field would be retarded by a factor of three. (USGS
Geohydrologic Conditions at the Nuclear-fuels Reprocessing Plant and Waste-management Facilities at the Western New York Nuclear Service Center, Cattaraugus County, New York
A nuclear-fuel reprocessing plant, a high-level radioactive liquid-waste tank complex, and related waste facilities occupy 100 hectares (ha) within the Western New York Nuclear Service Center near West Valley, N.Y. The facilities are underlain by glacial and postglacial deposits that fill an ancestrial bedrock valley. The main plant facilities are on an elevated plateau referred to as the north plateau. Groundwater on the north plateau moves laterally within a surficial sand and gravel from the main plant building to areas northeast, east, and southeast of the facilities. The sand and gravel ranges from 1 to 10 m thick and has a hydraulic conductivity ranging from 0.1 to 7.9 m/day. Two separate burial grounds, a 4-ha area for low-level radioactive waste disposal and a 2.9-ha area for disposal of higher-level waste are excavated into a clay-rich till that ranges from 22 to 28 m thick. Migration of an organic solvent from the area of higher level waste at shallow depth in the till suggests that a shallow, fractured, oxidized, and weathered till is a significant pathway for lateral movement of groundwater. Below this zone, groundwater moves vertically downward through the till to recharge a lacustrine silt and fine sand. Within the saturated parts of the lacustrine unit, groundwater moves laterally to the northeast toward Buttermilk Creek. Hydraulic conductivity of the till, based on field and laboratory analyses , ranges from 0.000018 to 0.000086 m/day. (USGS
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Plasma proteome correlates of lipid and lipoprotein: biomarkers of metabolic diversity and inflammation in children of rural Nepal.
Proteins involved in lipoprotein metabolism can modulate cardiovascular health. While often measured to assess adult metabolic diseases, little is known about the proteomes of lipoproteins and their relation to metabolic dysregulation and underlying inflammation in undernourished child populations. The objective of this population study was to globally characterize plasma proteins systemically associated with HDL, LDL, and triglycerides in 500 Nepalese children. Abnormal lipid profiles characterized by elevated plasma triglycerides and low HDL-cholesterol (HDL-C) concentrations were common, especially in children with subclinical inflammation. Among 982 proteins analyzed, the relative abundance of 11, 12, and 52 plasma proteins was correlated with LDL-cholesterol (r = -0.43∼0.70), triglycerides (r = -0.39∼0.53), and HDL-C (r = -0.49∼0.79) concentrations, respectively. These proteins included apolipoproteins and numerous unexpected intracellular and extracellular matrix binding proteins, likely originating in hepatic and peripheral tissues. Relative abundance of two-thirds of the HDL proteome varied with inflammation, with acute phase reactants higher by 4∼40%, and proteins involved in HDL biosynthesis, cholesterol efflux, vitamin transport, angiogenesis, and tissue repair lower by 3∼20%. Untargeted plasma proteomics detects comprehensive sets of both known and novel lipoprotein-associated proteins likely reflecting systemic regulation of lipoprotein metabolism and vascular homeostasis. Inflammation-altered distributions of the HDL proteome may be predisposing undernourished populations to early chronic disease
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