Avco Lycoming emission and flight test results

The Avco Lycoming flight test program for reduced emissions was conducted to determine and document the lean fuel schedule limits for current production aircraft based on flight safety. Based on analysis of the emissions profile, Avco Lycoming proposed to evaluate the effect of leaner schedules in the idle/taxi, climb, and approach modes. These modes were selected as areas where it was felt that possible improvements could be made with the greatest improvement in cyclic emissions reduction. The fuel systems to produce these leaner stepped fuel schedules were tailored specifically for the flight test

Salinity in Water Markets : An ExperimentalInvestigation of the Sunraysia Salinity Levy, Victoria

Irrigation can have a significant negative impact on the environment. Irrigation impacts contribute a significant portion to the estimated forty six million dollar cost per annum of salinity in the Murray River, Australia. Policies available to regulators include externality taxes and levies. In 2002 the Victorian Government introduced a system of salinity levies in the irrigation regions of Sunraysia, northern Victoria. These levies differ from typical taxes because they also introduce trade barriers between certain locations. These trade barriers may increase the cost of reducing salinity. We use experiments to compare the salinity levy with trade barriers to an alternative salinity tax which removes the trade barriers and replaces them with a ‘large’ tax relative to other geographic zones. Our results show that the salinity tax reduces the cost of salinity interception by the government by twenty five percent as compared to the salinity levy. We observe water prices do not increase when regulation is introduced, this may be because the introduction of taxes and levies encourages buyers to act more aggressively preventing sellers from extracting surplus on trades. Further, the introduction of regulation does not increase variability in average outcomes for these markets.Externality Taxes, Experiments, Double Auction, Environmental Policy, Salinity.

Avco Lycoming/NASA contract status

The standards promulgated by the Environmental Protection Agency (EPA) for carbon monoxide (CO), unburned hydrocarbon (HC), and oxides-of-nitrogen (NOx) emissions were the basis in a study of ways to reduce emissions from aircraft piston engines. A variable valve timing system, ultrasonic fuel atomization, and ignition system changes were postulated

General aviation piston-engine exhaust emission reduction

To support the promulgation of aircraft regulations, two airports were examined, Van Nuys and Tamiami. It was determined that the carbon monoxide (CO) emissions from piston-engine aircraft have a significant influence on the CO levels in the ambient air in and around airports, where workers and travelers would be exposed. Emissions standards were set up for control of emissions from aircraft piston engines manufactured after December 31, 1979. The standards selected were based on a technologically feasible and economically reasonable control of carbon monoxide. It was concluded that substantial CO reductions could be realized if the range of typical fuel-air ratios could be narrowed. Thus, improvements in fuel management were determined as reasonable controls

Report of the Terrestrial Bodies Science Working Group. Volume 4: The moon

A rationale for furture exploration of the moon is given. Topics discussed include the objectives of the lunar polar orbiter mission, the mission profile, and general characteristics of the spacraft to be used

High selectivity microporous silica membranes for lactic acid dehydration

Lactic acid (LA) has significant market potential for many industries including food, cosmetics, pharmaceuticals, medical and biodegradable materials. Production of LA usually begins with the fermentation of glucose but subsequent stages for the enrichment of lactic acid are complex and energy intensive and could be minimised using water selective membrane technology. In this work, we trialled a highly selective hydrostable carbonised template molecular sieve silica (CTMSS) membrane for the dehydration of a 15 vol% aqueous lactic acid solution with 0.1 vol% glucose. CTMSS membrane films were developed by dip-coating ceramic substrates with silica sols made using the acid catalysed sol-gel process. Permeation was performed by feeding LA/glucose solution to the membrane cell at 18°C in a standard pervaporation setup. The membrane showed selective transport of water from the aqueous feed to the permeate while glucose was not detected. CTMSS membrane permeate flux stabilised at 0.2 kg.m-2.hr-1 in 3.9 hours, and reduced LA to lower than 0.2 vol%. Flux through the CTMSS micropores was activated, displaying increased initial flux to 1.58 kg.m-2.hr-1 at 60°C. To enrich a 1 l.min-1 stream to 85% LA in a single stage, a minimum membrane area of 324 m2 would be required at 18°C. Increased operating temperature to 80°C significantly reduced this area to 24 m2 but LA levels in the permeate stream increased to 0.5 vol%. The highly selective CTMSS membrane technology is an ideal candidate for LA purification. CTMSS membrane systems operate stably in aqueous systems leading to potential cost reductions in LA processing for future markets

Report of the Terrestrial Bodies Science Working Group. Volume 5: Mars

Present knowledge of the global properties and surface characteraretics of Mars and the composition and dynamics of its atmosphere are reviewed. The objectives of proposed missions, the exploration strategy, and supporting research and technology required are delineated

A Matrix Approach to Numerical Solution of the DGLAP Evolution Equations

A matrix-based approach to numerical integration of the DGLAP evolution equations is presented. The method arises naturally on discretisation of the Bjorken x variable, a necessary procedure for numerical integration. Owing to peculiar properties of the matrices involved, the resulting equations take on a particularly simple form and may be solved in closed analytical form in the variable t=ln(alpha_0/alpha). Such an approach affords parametrisation via data x bins, rather than fixed functional forms. Thus, with the aid of the full correlation matrix, appraisal of the behaviour in different x regions is rendered more transparent and free of pollution from unphysical cross-correlations inherent to functional parametrisations. Computationally, the entire programme results in greater speed and stability; the matrix representation developed is extremely compact. Moreover, since the parameter dependence is linear, fitting is very stable and may be performed analytically in a single pass over the data values.Comment: 13 pages, no figures, typeset with revtex4 and uses packages: acromake, amssym

Transmission of a Symmetric Light Pulse through a Wide QW

The reflection, transmission and absorption of a symmetric electromagnetic pulse, which carrying frequency is close to the frequency of an interband transition in a QW (QW), are obtained. The energy levels of a QW are assumed discrete, one exited level is taken into account. The case of a wide QW is considered when a length of the pulse wave, appropriate to the carrying frequency, is comparable to the QW's width. In figures the time dependencies of the dimensionless reflection, absorption are transmission are represented. It is shown, that the spatial dispersion and a distinction in refraction indexes influence stronger reflection.Comment: 8 pages,8 figures with caption