91,492 research outputs found
Effect of refining variables on the properties and composition of JP-5
Potential future problem areas that could arise from changes in the composition, properties, and potential availability of JP-5 produced in the near future are identified. Potential fuel problems concerning thermal stability, lubricity, low temperature flow, combustion, and the effect of the use of specific additives on fuel properties and performance are discussed. An assessment of available crudes and refinery capabilities is given
Non-local 2D Generalized Yang-Mills theories on arbitrary surfaces with boundary
The non-local generalized two dimensional Yang Mills theories on an arbitrary
orientable and non-orientable surfaces with boundaries is studied. We obtain
the effective action of these theories for the case which the gauge group is
near the identity, . Furthermore, by obtaining the effective action
at the large-N limit, it is shown that the phase structure of these theories is
the same as that obtain for these theories on orientable and non-orientable
surface without boundaries. It is seen that the model of these
theories on an arbitrary orientable and non-orientable surfaces with boundaries
have third order phase transition only on and surfaces, with
modified area for orientable and
for non-orientable surfaces respectivly.Comment: 10 pages, no figures, late
Fluoroether modified epoxy composites
Addition of controlled amounts of perfluorinated alkyl ether diacyl fluoride to epoxy resin systems prior to cure results in a formulation which, exhibits improved energy absorbing properties
Optimizing Dual Interdependent Products from a Single Crop
The objective of the research is to determine the optimal grazing termination date that maximizes expected net returns from dual-purpose winter wheat production. Preliminary results indicate that grazing should be terminated at or before first hollow stem to generate the highest expected net returns in a dual-purpose winter wheat production enterprise.Crop Production/Industries,
Australian Growth: A California Perspective
Examination of special cases assists understanding of the mechanics of long-run economic growth more generally. Australia and California are two economies having the rare distinction of achieving 150 years of sustained high and rising living standards for rapidly expanding populations. They are suitable comparators since in some respects they are quite similar, especially in their initial conditions in the mid-nineteenth century, their legal and cultural inheritances, and with respect to some long-term performance indicators. However, their growth trajectories have differed markedly in some sub-periods, and over the longer term with respect to the growth in the size of their economies. Most important, the comparison of an economy that remained a region in a much larger national economy with one that evolved into an independent political unit helps identify the role of several key policies. California had no independent monetary policy, or exchange rate, or controls over immigration or capital movements, or trade policy. Australia did, and after 1900 pursued an increasingly interventionist and inward-oriented development strategy until the 1970s. What difference did this make to long-run growth? And what other factors, exogenous and endogenous, account for the differences that have emerged between two economies that shared such similar initial conditions?
Demonstration of the feasibility of automated silicon solar cell fabrication
A study effort was undertaken to determine the process, steps and design requirements of an automated silicon solar cell production facility. Identification of the key process steps was made and a laboratory model was conceptually designed to demonstrate the feasibility of automating the silicon solar cell fabrication process. A detailed laboratory model was designed to demonstrate those functions most critical to the question of solar cell fabrication process automating feasibility. The study and conceptual design have established the technical feasibility of automating the solar cell manufacturing process to produce low cost solar cells with improved performance. Estimates predict an automated process throughput of 21,973 kilograms of silicon a year on a three shift 49-week basis, producing 4,747,000 hexagonal cells (38mm/side), a total of 3,373 kilowatts at an estimated manufacturing cost of 1.22 per watt
Central role for the XRCC1 BRCT I domain in mammalian DNA single-strand break repair
The DNA single-strand break repair (SSBR) protein XRCC1 is required for genetic stability and for embryonic viability. XRCC1 possesses two BRCA1 carboxyl-terminal (BRCT) protein interaction domains, denoted BRCT I and II. BRCT II is required for SSBR during G1 but is dispensable for this process during S/G2 and consequently for cell survival following DNA alkylation. Little is known about BRCT I, but this domain has attracted considerable interest because it is the site of a genetic polymorphism that epidemiological studies have associated with altered cancer risk. We report that the BRCT I domain comprises the evolutionarily conserved core of XRCC1 and that this domain is required for efficient SSBR during both G1 and S/G2 cell cycle phases and for cell survival following treatment with methyl methanesulfonate. However, the naturally occurring human polymorphism in BRCT I supported XRCC1-dependent SSBR and cell survival after DNA alkylation equally well. We conclude that while the BRCT I domain is critical for XRCC1 to maintain genetic integrity and cell survival, the polymorphism does not impact significantly on this function and therefore is unlikely to impact significantly on susceptibility to cancer
A modified Newton-Raphson analysis of flight measurements of the trailing vortices of a heavy jet transport
A modified Newton-Raphson method has been used to determine the parameters in equations describing the vortex flow to obtain a best match with flight measurements of the flow behind the C-5A airplane. The flight measurements were made using a specially instrumented T-33 airplane which passed as closely as possible to the centers of the trailing vortices at several distances behind the C-5A airplane. The flight measurements were transformed to flow velocity relative to an inertial frame of reference. The assumed form of the flow consisted of the superposition of two counterrotating, finite core vortices. The positions of the vortex centers, their total circulation, the effective eddy viscosity and measurement bias were the parameters adjusted. The assumed form of vortex flow fit well the measured velocities for the numerous sets of data, both flaps up and down for the C-5A airplane. The resulting values of total circulation, however, were about two-thirds that expected of a wing with an elliptical loading. A partial explanation of the less than expected circulation is a dip in the spanwise lift distribution at the airplane's center line. The distance between the trailing vortices at the smallest times encountered is somewhat less than that expected for an elliptical wing loading
- …