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Fast-Track Remedial Design of Full-Scale ISCO Application Using Pilot Scale Testing and Field Screening Parameters
As a result of drum re-finishing operations, soil and groundwater at the Ottati and Goss Superfund Site in Kingston, NH are contaminated with chlorinated volatile organic compounds (VOCs); benzene, toluene, ethylbenzene, and xylene (BTEX); and 1,4-dioxane. After re-evaluation of the selected remedy for groundwater, pump and treat, EPA changed the remediation approach to in-situ chemical oxidation (ISCO) through an Amended Record of Decision in September 2007. At that time, EPA established a goal for the site to attain construction complete status within one year, by September 30, 2008.
Activated persulfate was selected as the chemical oxidant for its capability to oxidize 1,4-dioxane, in addition to the other VOC contaminants of concern. Bench-scale and field pilot scale test were completed in three source areas to collect site-specific information to evaluate persulfate\u27s ability to destroy the contaminants of concern and to optimize full-scale remediation design in three discrete source areas at the site. Base-activated persulfate was injected in Areas A and B in December 2007, and pilot test injection was completed in Area C in early February 2008, after vertical profiling was completed throughout Area C. Groundwater sampling for laboratory analysis was planned for 6 and 12 weeks after injection in each area; however, it was known during pilot test planning that the full-scale design would need to be completed by the end of March 2008, before all laboratory results would be available. In order to complete the design, an intensive evaluation of field geochemistry parameters and field screening chemical analysis was performed to assess radius of influence, oxidant persistence, and aquifer behavior. Field screening analyses included residual persulfate via a permanganate titration, sulfate via colorimetry, and sodium via an ion-selective electrode. The field screening and field geochemistry results were used heavily in completing the full-scale ISCO design. The laboratory analytical results noted significant decreases in concentrations of chemicals of concern in wells where geochemistry and field parameters were observed to change. This article discusses pilot test planning, performance monitoring, and full-scale design using data collected from the pilot test for this fast-track remediation. The full-scale application was completed between July and September 2008, and was the third largest single-site application of persulfate performed to date
Whole body active warm up and inspiratory muscle warm up do not improve running performance when carrying thoracic loads
Whole body active warm ups (AWU) and inspiratory muscle warm up (IMW) prior to exercise improves performance on some endurance exercise tasks. This study investigated the effects of AWU with and without IMW upon 2.4 km running time-trial performance while carrying a 25 kg backpack, a common task and backpack load in physically demanding occupations. Participants (n = 9) performed five 2.4 km running time-trials with a 25 kg thoracic load preceded in random order by 1) IMW comprising 2 x 30 inspiratory efforts against a pressure-threshold load of 40 % maximal inspiratory pressure (PImax), 2) 10 min unloaded running (AWU) at lactate turnpoint (10.33 ± 1.58 km·h-1), 3) placebo IMW (PLA) comprising five min breathing using a sham device, 4) AWU+IMW and 5) AWU+PLA. Pooled baseline PImax was similar between trials and increased by 7% and 6% following IMW and AWU+IMW (P0.05). Time-trial performance was not different between any trials. Whole body AWU and IMW performed alone or combination have no ergogenic effect upon high intensity, short duration performance when carrying a 25 kg load in a backpack.N/
Board 417: Understanding Capstone Design Activity Engagement in Mechanical Engineering
This paper summarizes the initial findings of our ongoing work studying design activity engagement for engineering students and professionals. With this introductory study, we aim to gain a better understanding of how engineering students engage in capstone design activities, and their motivations for doing so. This paper presents the initial findings from semi-structured interviews with three engineering students and will constitute the base for further research focusing on student and professional engagement in design activity across different engineering fields
Some Biological Effects of Certain Nitrogen Fertilizers
Numerous investigations in the past have shown that nitrogen fertilizers may exert a rather pronounced stimulative effect upon certain biological soil processes. The results of such a stimulation may prove distinctly beneficial to crop growth and the effects of the treatment may, therefore, be of economic significance
Machine vision in conjunction with a knowledge-based system for semi-automatic control of a gravure printing process
This paper describes the work carried out to produce an automated print inspection system, which was developed on a gravure printing press within the wall-covering printing industry. The project aim was to produce a system that could continuously monitor the gravure printing process, by examining printed material using machine vision, and then by using a fuzzy knowledgebased system to interpret the machine vision system output and to make recommendations to an operator as to how to correct the process with simple text-based suggestions, avoiding printing of scrap material
Prognostic value of electrical impedance spectroscopy (EIS) when used as an adjunct to colposcopy – a longitudinal study
Objective
Colposcopy can be used with Electrical Impedance Spectroscopy (EIS) as an adjunct, to assess the presence of High Grade Cervical Intra-epithelial Neoplasia (CIN2+). This analysis of longitudinal data has used the results from women with a negative colposcopy, in order to see if the initial (index) EIS results were able to predict the women who subsequently developed CIN2+. A further objective was to investigate what tissue structural changes might be reflected in the electrical impedance spectra.
Methods
847 patients were referred with low grade cytologly. EIS measurements were made around the transformation zone of the cervix during colposcopy. Every EIS spectrum was matched to a template representing CIN2+ and the result was positive if the match exceeded a probability index threshold. The colposcopic impression was also recorded. All the women who developed biopsy proven CIN2+ within three years of the index colposcopy were identified.
Results
The median follow-up was 30.5 months. Where both CI and EIS were initially positive, there was an increased prevalence (8.13%) of CIN2+ developing as opposed to 3.45% in the remaining patients (p=0.0159). In addition, if three or more EIS spectra were positive there was a higher prevalence (9.62% as opposed to 3.56% p=0.0132) of CIN2+ at three years. The index spectra recorded from the women who developed CIN2+ showed EIS changes consistent with increases in the extracellular volume and in cell size inhomogeneity.
Conclusion
EIS does offer prognostic information on the risk of CIN2+ developing over the three-year period following the EIS measurements. The changes in EIS spectra are consistent with an increase in cell size diversity as pre-malignancy develops. These changes may be a consequence of increased genetic diversity as neoplasia develops
Relationship Between Tissue Zinc Levels and Maturity Period of Field Beans
Most bean varieties (Phaseolus vulgaris) are susceptible
to zinc deficiency and, if grown where
zinc deficiency occurs, are invariably listed among
those crops with the greatest need for zinc fertilization
(1, 2, 3, 4). Bean plants with mild to moderate zinc deficiency
symptoms early in the growing season may
recover and produce essentially a normal yield. However,
as several individuals have observed (1, 2, 3)
this early-season zinc deficiency invariably results in
delayed maturity. This is a critical factor in geographical
areas where beans may be damaged by fall
rains or early frost.
The research reported here establishes quantitative
relationships between the zinc level in bean tissues
and the number of days required for maturation. The
results support previous observations of delayed maturity
when bean plants have inadequate zinc during
early growth
Evaluation of changes in microbial populations on beef carcasses resulting from steam pasteurization
The steam pasteurization process (SPS
400) developed by Frigoscandia Food Process Systems (Bellevue, WA) was effective in reducing
bacterial populations in both laboratory and commercial settings. The objective
of steam pasteurization and other meat decontamination
measures is to extend product
shelf life and improve safety by inhibiting or
inactivating pathogens, while at the same time
maintaining acceptable meat quality characteristics.
The effects of steam pasteurization
on beef carcass bacterial populations
were evaluated at two large commercial beef
processing facilities. A shelf-life study also
was conducted to determine the microbial
profiles of vacuum packaged beef loins from
pasteurized and non-pasteurized carcasses.
Steam pasteurization greatly reduced total
beef carcass bacterial populations and was
most effective in reducing gram negative
organisms, including potential enteric pathogens
of fecal origin. Thus, the relative percentage of gram positive microflora on beef carcass surfaces, especially Bacillus spp. and
Staphylococcus spp., increased
Magnetisation switching in a ferromagnetic Heisenberg nanoparticle with uniaxial anisotropy: A Monte Carlo investigation
We investigate the thermal activated magnetisation reversal in a single
ferromagnetic nanoparticle with uniaxial anisotropy using Monte Carlo
simulations. The aim of this work is to reproduce the reversal magnetisation by
uniform rotation at very low temperature in the high energy barrier hypothesis,
that is to realize the N\'eel-Brown model. For this purpose we have considered
a simple cubic nanoparticle where each site is occupied by a classical
Heisenberg spin. The Hamiltonian is the sum of an exchange interaction term, a
single-ion anisotropy term and a Zeeman interaction term. Our numerical data of
the thermal variation of the switching field are compared to an approximated
expression and previous experimental results on Co nanoparticles
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