3,326 research outputs found
Dynamic Geotechnical Comparative Testing Capability
A concept and preliminary design are presented for a special testing capability to be added to an existing large laboratory geotechnical testing chamber. The modified chamber is intended to allow, through comparative testing, the reasonably rigorous evaluation of methods for providing detailed information, for soil deposits, on in situ undegraded nonlinear inelastic shear stress vs strain characteristics needed for dynamic geotechnical earthquake engineering analyses. Basically, the added capability is to be a large resonant column-like torsional testing system that tests the entire chamber sample and allows access to the center of the sample for the testing of the method to be evaluated. The main features of the modified test chamber are meant to be that 1) tests of methods to be evaluated and comparative tests are to be conducted on the same sample and 2) the comparative testing method is to provide the information of interest
In Situ Torsional Cylindrical Shear Test-Laboratory Results
We present results from cyclic tests conducted in the laboratory using a prototype in situ cyclic torsional cylindrical shear geotechnical testing system. The system is intended to advance our ability to design critical systems to resist earthquakes by improving our ability to analytically predict the behavior of soil-structure-equipment systems during earthquakes. It is to do so by providing, more reliably than we feel is now possible, estimates of the in situ cyclic shear stress vs strain characteristics needed by refined earthquake analyses. These characteristics include 1) resistances to initial liquefaction, cyclic degradation, and large cyclic deformations, and 2) undegraded, nonlinear, inelastic characteristics. The testing system was found to be effective under representative controlled laboratory conditions and promising for field use. Test results were found to be reasonable and consistent with published results of laboratory tests of a high quality. Additionally, we did not observe major limitations or encounter abnormal difficulties
Charged particle tracks in polymers number 6 - A method for charge determination of heavy, multicharged cosmic ray particles
Charge determination of heavy, multicharged cosmic ray particles from particle tracks in cellulose nitrate nuclear emulsion stack
Chemistry and environmental implications of thio-red and 2,4,6-trimercaptotriazine compounds
Many compounds, including Thio-Red® and 2,4,6-trimercaptotriazine, trisodium salt (TMT-55), have been marketed to precipitate mercury and other heavy metals from water, including contaminated ground waters. For the products to be effective, information is needed on the chemistry of the products, how they precipitate metals from aqueous solutions, and the chemistries and stabilities of the precipitates.
CS32-, HS-, and S2- are the dominant sulfur species in Thio-Red®. They precipitate heavy metals from water as sulfides (e.g., HgS, PbS, and ZnS). Thio-Red® also contains traces of poisonous carbon disulfide (CS2). Additional CS2 could form from reactions between dissolved heavy metals and CS32-. Large volumes of undiluted Thio-Red® should not be injected into low oxygen environments for in situ restoration until studies eliminate the possibility of contamination from CS2 or H2S.
TMT-55 is Na3C3N3S3•9H20. The crystallographic data at 25°C are R3, Z = 6, a= 17.600(1) A, c = 9.720(2) A, V= 2607.5(5) A3, and a density of 1.55 g/cm3•
The precipitation of divalent mercury with TMT-55 may produce one or more mercury 2,4,6-trimercaptotriazine (HgTMT) compounds, including white, greenish yellow to greenish brown, gray, or yellow varieties. The white variety probably contains mercury(I). White HgTMT is monoclinic with a= 5.904(3) A, b = 6.966(1) A, c = 4.572(1) A, /3= 104.85(2)0, and V= 181.79 A3. Within three months, white HgTMT may decompose in air or aerated water to the yellow or gray varieties. In batch leachates with distilled and deionized water, white HgTMT may release more than 3 milligrams/liter of mercury. Mercury concentrations in water leachates of gray and bright yellow samples are relatively low (3.3 - 53 micrograms/liter). The gray, yellow and greenish varieties still require extensive chemical analyses and leaching studies to identify any leachable organic compounds. TMT-55 should not be used in the in situ restoration of mercury contaminated sites until the resulting precipitates are known to be stable.
Studies ofBalC3N3S3) 2•8H20 and BaHiC3N3S3) 2•4.5H20 (BaTMT compounds) were initiated to determine ifTMT-55 could be used to remove barium from water. However, the aqueous solubilities of both compounds are probably too high (around 5 grams/liter) for effective barium removal.
The results of powder XRD analyses show that B(C3N3S3) 2•8H20 is either hexagonal or orthorhombic. The results of a single crystal analysis of BaHiC3N3S3) 2•4.5H20 at 25°C state that the compound is monoclinic (P2/c) with Z = 4, calculated density= 2.077 g/cm3, a= 8.5576(4) A, b = 21.028(1) A, c = 20.276(1) A, /J= 96.440(1)0, and V= 3625.6(3) A3
Archean metamorphism in northwestern Ontario and southeastern Manitoba
Four areas are considered in this study. In Ontario, north-south traverses were made along Highway 599 between Savant Lake and Central Patricia, along the Vermilion River road (40 kilometers northeast of Sioux Lookout) and along Highway 105 between Vermilion Bay and Ear Falls (Fig. 3). The fourth area is centered at Bird River, northeast of Lac du Bonnet, Manitoba. The study areas are located in the Uchi, English River and Wabigoon Subprovinces.
The traverse along Highway 599 between Savant Lake and Central Patricia crosses the three subprovinces (Fig. 3). Pelites in the eastern Lake St. Joseph area (Uchi Sub province) and Wabigoon Subprovince indicate that metamorphic conditions were 2-4 kb and 425-600°C (Fig. 3).
The Vermilion River logging road crosses the English River Subprovince and has four lithologies that are useful in determining metamorphic conditions: hypersthene ± clinopyroxene granulites, biotite, biotite-garnet, and biotite-garnet-cordierite paragneisses (Fig. 3). Garnet cordierite geobarometry yielded pressures of 3.8-6.S kb. The metamorphic temperatures increased slightly for the four lithologies: biotite gneisses (\u3c610-650°C), biotite-garnet gneisses (610-670°C), and granulites and biotite-garnet cordierite gneisses (650-750°C) .
The Red Lake road traverse crosses 3-4 km of the extreme northern Wabigoon Subprovince and approximately 90 km of the English River Subprovince (Fig. 3). The rocks of the North and South Domains of the English River Sub province were probably metamorphosed at 650-750°C and 5-7.5 kb.
The Bird River greenstone belt is located approximately 200 km northeast of Winnipeg in the English River Subprovince (Fig. 3, 34). Metamorphic temperatures were usually 450-600°C and were estimated from metamorphic assemblages. The common occurrence of andalusite in the pelites suggests that metamorphic pressures did not exceed 4 kb in most of the belt. Carbonate-rich rnetabasites at the Bird River Bridge may have had Xco2 values that exceeded 0.15.
Two tectonic models for the formation of the Uchi, English River, and Wabigoon subprovinces were derived from the pressure and temperature data, along with geophysical and structural information from other studies. A non subduction model assumes that Archean plates were too thin and hot to be subducted (Fig. 43-47). The plate tectonics model includes subducting plates and is based on the work of Langford and Morin (1976) (Fig. 49)
Repairing Infrastructures
An investigation of the causes and consequences of the strange, ambivalent, and increasingly central role of infrastructure repair in modern life. Infrastructures—communication, food, transportation, energy, and information—are all around us, and their enduring function and influence depend on the constant work of repair. In this book, Christopher Henke and Benjamin Sims explore the causes and consequences of the strange, ambivalent, and increasingly central role of infrastructure repair in modern life. Henke and Sims offer examples, from local to global, to investigate not only the role of repair in maintaining infrastructures themselves but also the social and political orders that are created and sustained through them. Repair can encompass not only the kind of work we most commonly associate with the term but also any set of practices aimed at restoring a sense of normalcy or credibility to the places and institutions we inhabit in everyday life. From cases as diverse as the repair of building systems on a university campus, a conflict over retrofitting a bridge while protecting murals painted on it, and the global challenge posed by climate change, Henke and Sims assemble a range of examples to illustrate key conceptual points about the role of repair. They show that repair is an essential if often overlooked aspect of understanding the broader impact and politics of infrastructures. Understanding repair helps us better understand infrastructures and the scope of their influence on our lives
DEVELOPMENT OF VIRTUAL EVENT MARKETING
In the last few years the Pichia pastoris expression system has been gaining more and more interest for the expression of recombinant proteins. Many groups have employed fermentation technology in their investigations because the system is fairly easy to scale up and suitable for the production in the milligram to gram range. A large number of heterologous proteins from different sources has been expressed, but the fermentation process technology has been investigated to a lesser extent. A large number of fermentations are carried out in standard bioreactors that may be insufficiently equipped to meet the demands of high-cell-density fermentations of methylotrophic yeasts. In particular, the lack of on-line methanol analysis leads to fermentation protocols that may impair the optimal expression of the desired products. We have used a commercially available methanol sensor to investigate in detail the effects of supplementary glycerol feeding while maintaining a constant methanol concentration during the induction of a Mut+ strain of Pichia pastoris. Specific glycerol feed rates in the range of 38-4.2 mg × g(exp -1) × h(exp -1) (mg glycerol per gram fresh weight per hour) were investigated. Expression of the recombinant scFv antibody fragment was only observed at specific feed rates below 6 mg × g(exp -1) × h(exp -1). At low specific feed rates, growth was even lower than with methanol as the sole carbon source and the harvest expression level of the scFv was only half of that found in the control fermentation. These results show that glycerol inhibits expression driven by the AOX1 promoter even at extremely limited availability and demonstrate the benefits of on-line methanol control in Pichia fermentation research
L-1011 testing with relaxed static stability
Wind tunnel and flight tests indicate that fuel savings of 2 percent can be achieved by center of gravity (C.G.) management for an L-1011 with the current wing configuration. The normal c.b. location is at 25 percent mean aerodynamic center (MAC). The maximum fuel saving occurs for a C.G. location of 35 percent MAC. However, flight at 35 percent requires that the C.G. range be extended aft of the 35-percent point. Flight at C.G. locations aft or 35 percent requires a pitch active control system (PACS) so that handling qualities are not significantly degraded. The development of this PACS is discussed
Charged particle tracks in polymers - No. 3 - Range and energy loss tables
Range and energy loss for ions tabulated from charged particle tracks in polymer
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