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[en] A description is given of a radioactive source manipulator and stowage device comprising: a cylindrical body; a transversely disposed socket formed near one end of said cylindrical body for receiving a radioactive source; a cylindrical sleeve rotatably mounted on said cylindrical body; and an aperture formed in the wall of said sleeve whereby rotation of said sleeve to axially align said aperture with said socket will permit a radioactive source to be inserted into and removed from said socket and rotation of said sleeve to move said aperture out of alignment with said socket when the socket contains a radioactive source readies the device for manipulation and stowage
[en] This report evaluates a simplified technique for estimating methanol emission rates in auto exhaust. The technique, referred to as the FID Bubbled Method or FBM, is based in principle on the fact that, while hydrocarbons are not readily absorbed in water, methanol is. Hence, by using a heated flame ionization detector to measure the organic mass in samples before and after bubbling them in water, the quantity of methanol originally present can be estimated by taking the difference between the measurements. Evaluation of the method was done by comparing methanol measurements using the FBM with measurements made using an established reference method. Results showed poor to fair agreement between the two methods. The FBM appeared better at estimating methanol emission rates from evaporative tests than from exhaust tests and also exhibited better accuracy for samples containing higher levels of methanol
[en] Poor management of pig slurry can lead to the contamination of the soil, water and air, which is mostly of the result of sur-plus nutrients. Such environmental impact from pig farming are common in areas with intensive livestock farming. The projects primary objectives is to demonstrate at farm scale the application of the three main manure management technologies deployed within structured local schemes to minimize the environmental impact. (Author)
[en] Check valves are located in almost all safety and non-safety related fluid systems in a nuclear power plant. Malfunction or failure of these valves during plant operations, or in some cases under cold shutdown conditions, can seriously affect plant safety and result in costly, time-consuming maintenance. A major cause of check valve failure in the past has been excessive wear of internal components due to high disc flutter. Valve operation under conditions that cause the valve disc and hinge arm to oscillate or flutter can lead to degradations which, if undetected and not corrected, may result in malfunction or failure. Checkmate II, a portable, non-intrusive diagnostic system, has been developed to test various types of check valves using patented ultrasonic testing technology. The system comprises a computer, ultrasonic oscilloscope, transducers, and supporting hardware, and can identify many different phenomena, including: disc position and disc flutter; backstop and seat tapping; relative motion between hinge arm and disc; hinge pin wear and uneven hinge pin wear; disc stud wear and loosened stud nuts; combined stud and hinge pin wear, stuck and missing discs; broken springs. (author)
[en] Emissions from seven late-model popular V-6 and V-8 motor vehicles were characterized at three test temperatures. Six vehicles fueled by port fuel injection (PFI) and one vehicle with a carbureted fuel system were tested at temperatures of 75, 90, and 105F with unleaded regular summer grade gasoline. Tailpipe and evaporative emissions were determined at each test temperature. Measured emissions were the total hydrocarbons (THCs), speciated hydrocarbons, speciated aldehydes, carbon monoxide (CO), oxides of nitrogen (NOx), benzene, and 1,3-butadiene. In general, tailpipe emissions of THC, benzene, and 1,3-butadiene from the vehicles were not temperature sensitive, but the Co and NOx emissions showed some temperature sensitivity. Formaldehyde, acetaldehyde, and total aldehyde emissions from the PFI vehicles were also not temperature dependent, while formaldehyde emissions from the carbureted vehicle decreased slightly with increasing test temperature. Evaporative THC emissions generally increased with increasing test temperature. Hydrocarbon emissions saturated and broke through the evaporative carbon canister of one PFI vehicle during the 105F hot soak while the other six vehicles showed no hydrocarbon breakthrough
[en] Feedstock production for large scale development of the U.S. ethanol industry and introduction of cellulose-to-ethanol technology will require extensive changes in land use and field management. Hence, this production will likely have significant impact on water demand and quality. This study compares two 'what if' scenarios for attaining a 227.1 hm3 of ethanol by 2030 and 3.8 hm3 of biodiesel by 2012. In the first scenario cellulose-to-ethanol technology is introduced in 2012, while in the second scenario the technology is delayed until 2015. Results show that the timing of introduction of cellulose-to-ethanol technology will affect the water use and water quality related input use in primarily in the eastern part of the nation. Results also suggest policy emphasis on reduced and no-till practices needs to be complementary to increased crop residue use. (author)
[en] Willingness to pay (WTP) for E85 (automotive fuel blend of 85% ethanol and 15% gasoline) was estimated from a contingent choice exercise contained in a national survey of consumers. The choice exercise included E85 blends from three different feedstock sources (corn grain, switchgrass, and wood wastes) and an E10 blend (10% ethanol and 90% gasoline) with corn grain as the ethanol feedstock. Results from the study indicate willingness to pay a premium for E85 from switchgrass compared with E10 from corn. Concerns about land use for ''food versus fuel'' had a negative impact on WTP for E85 from corn grain, while greater concerns about fuel security relative to the environment had a positive impact. (author)
[en] Changes in environmental perception during an EIA process among the general population (the public) and employees of the Port of Koper were measured. The method of measurement addresses the statistical significance of the influence of the content, form, mode, providers of environmental information, institutional constraint and other factors. Opinions about environmental issues were collected in both groups prior to and after the provision of information in the EIA process. The difference formed the basis for an assessment of how environmental information provided during an EIA process contributes to environmental perception. The results show that difference in opinions about the impact of the Port between the two groups became smaller when comparing the first and second survey. In relation to the opinions of the employees, institutional constraint was recognised
[en] Highlights: • Perennial switchgrass can reduce nitrate loadings and improve water quality. • Multi-objective optimization is applied to spatial data for switchgrass supply. • Average grey water footprint of switchgrass ranges 132–146 L L−1 of ethanol. • Tradeoffs between biomass costs and water quality are driven by land use changes. • Cost of reducing grey water footprint in west Tennessee averages $0.94 m−3. - Abstract: Producing renewable fuel from dedicated energy crops, such as switchgrass, has the potential to generate localized environmental benefits. This study uses high-resolution spatial data for west Tennessee to quantify the effects of producing switchgrass for cellulosic ethanol on the grey water footprint (GWF), or the amount of freshwater needed to dilute nitrate leachate to a safe level, relative to existing agricultural production. In addition, the estimated cost and GWF are incorporated in a mixed-integer multi-objective optimization model to derive the efficient frontier of the feedstock supply chain and determine a switchgrass supply chain that achieves the greatest reduction in GWF at the lowest cost. Results suggest that background nitrate concentration in ambient water and the types of agricultural land converted to switchgrass production influence the extent of the GWF. The average GWF of switchgrass in the study area ranges between 131.8 L L−1 and 145.9 L L−1 of ethanol, which falls into the range of estimated GWF of other lignocellulosic biomass feedstock in the literature. Also, the average cost of reducing GWF from the feedstock supply chain identified by the compromise solution method is $0.94 m−3 in the region. A tradeoff between biofuel production costs and reduced nitrate loading in groundwater is driven by differences in the agricultural land converted to feedstock production. Our findings illustrate the energy-water-food nexus in the development of a local bioenergy sector and provide a management strategy associated with land use choices for the supply of energy crops. However, the water quality improvements associated with displacing crop with feedstock production in one region could be offset by expanded or more intensive agricultural production in other regions.
[en] Highlights: • Conventional fuel price uncertainty and policy uncertainty impact entry into the biofuel market. • Uncertainty associated with future RIN prices limits the effectiveness of the RIN program. • Tax incentives could counteract the effect of the volatile RIN prices for market entry but not exit. Uncertainty has been cited as one possible explanation for the lackluster performance of the Renewable Fuel Standard, which was enacted to encourage investment in the production of advanced biofuel. The unpredictability of conventional fuel markets makes the revenues and costs associated with biofuel production uncertain. In addition, policy uncertainty, in the form of annual revisions and adjustments to the program, make the cost of complying with the Renewable Fuel Standard uncertain. This paper is the first to decompose the aggregate uncertainty facing biofuel producers and isolate the effect of fuel market uncertainty and policy uncertainty on the decision to enter and exit the biofuel market. Results indicate that the uncertainty in the conventional fuel markets and the uncertainty in status of the Renewable Fuel Standard program influence incentives to enter and exit the biofuel market in different ways. Annual adjustments to the standard coupled with the unpredictable expiration and reinstatement of blender tax credits can work to discourage investment in biofuels and undermine effectiveness of the program.