309 research outputs found
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Greenridge Multi-Pollutant Control Project Preliminary Public Design Report
The Greenidge Multi-Pollutant Control Project is being conducted as part of the U.S. Department of Energy's Power Plant Improvement Initiative to demonstrate an innovative combination of air pollution control technologies that can cost-effectively reduce emissions of SO{sub 2}, NO{sub x}, Hg, acid gases (SO{sub 3}, HCl, and HF), and particulate matter from smaller coal-fired electrical generating units (EGUs). The multi-pollutant control system includes a hybrid selective non-catalytic reduction (SNCR)/in-duct selective catalytic reduction (SCR) system to reduce NOx emissions by {ge}60%, followed by a Turbosorp{reg_sign} circulating fluidized bed dry scrubber system to reduce emissions of SO{sub 2}, SO{sub 3}, HCl, and HF by {ge}95%. Mercury removal of {ge}90% is also targeted via the co-benefits afforded by the in-duct SCR, dry scrubber, and baghouse and by injection of activated carbon upstream of the scrubber, as required. The technology is particularly well suited, because of its relatively low capital and maintenance costs and small space requirements, to meet the needs of coal-fired units with capacities of 50-300 MWe. There are about 440 such units in the United States that currently are not equipped with SCR, flue gas desulfurization (FGD), or mercury control systems. These smaller units are a valuable part of the nation's energy infrastructure, constituting about 60 GW of installed capacity. However, with the onset of the Clean Air Interstate Rule, Clean Air Mercury Rule, and various state environmental actions requiring deep reductions in emissions of SO{sub 2}, NO{sub x}, and mercury, the continued operation of these units increasingly depends upon the ability to identify viable air pollution control retrofit options for them. The large capital costs and sizable space requirements associated with conventional technologies such as SCR and wet FGD make these technologies unattractive for many smaller units. The Greenidge Project aims to confirm the commercial readiness of an emissions control system that is specifically designed to meet the environmental compliance requirements of these smaller coal-fired EGUs. The multi-pollutant control system is being installed and tested on the AES Greenidge Unit 4 (Boiler 6) by a team including CONSOL Energy Inc. as prime contractor, AES Greenidge LLC as host site owner, and Babcock Power Environmental Inc. as engineering, procurement, and construction contractor. All funding for the project is being provided by the U.S. Department of Energy, through its National Energy Technology Laboratory, and by AES Greenidge. AES Greenidge Unit 4 is a 107 MW{sub e} (net), 1950s vintage, tangentially-fired, reheat unit that is representative of many of the 440 smaller coal-fired units identified above. Following design and construction, the multi-pollutant control system will be demonstrated over an approximately 20-month period while the unit fires 2-4% sulfur eastern U.S. bituminous coal and co-fires up to 10% biomass. This Preliminary Public Design Report is the first in a series of two reports describing the design of the multi-pollutant control facility that is being demonstrated at AES Greenidge. Its purpose is to consolidate for public use all available nonproprietary design information on the Greenidge Multi-Pollutant Control Project. As such, the report includes a discussion of the process concept, design objectives, design considerations, and uncertainties associated with the multi-pollutant control system and also summarizes the design of major process components and balance of plant considerations for the AES Greenidge Unit 4 installation. The Final Public Design Report, the second report in the series, will update this Preliminary Public Design Report to reflect the final, as-built design of the facility and to incorporate data on capital costs and projected operating costs
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Addendum to Guarantee Testing Results from the Greenidge Multi-Pollutant Control Project: Additiona NH3, NOx, and CO Testing Results
On March 28-30 and May 1-4, 2007, CONSOL Energy Inc. Research & Development (CONSOL R&D) performed flue gas sampling at AES Greenidge to verify the performance of the multi-pollutant control system recently installed by Babcock Power Environmental Inc. (BPEI) on the 107-MW Unit 4 (Boiler 6). The multi-pollutant control system includes combustion modifications and a hybrid selective non-catalytic reduction (SNCR)/in-duct selective catalytic reduction (SCR) system to reduce NO{sub x} emissions, followed by a Turbosorp{reg_sign} circulating fluidized bed dry scrubber system and baghouse to reduce emissions of SO{sub 2}, SO{sub 3}, HCl, HF, and particulate matter. Mercury removal is provided via the co-benefits afforded by the in-duct SCR, dry scrubber, and baghouse and by injection of activated carbon upstream of the scrubber, as required. The testing in March and May demonstrated that the multi-pollutant control system attained its performance targets for NO{sub x} emissions, SO{sub 2} removal efficiency, acid gas (SO{sub 3}, HCl, and HF) removal efficiency, and mercury removal efficiency. However, the ammonia slip measured between the SCR outlet and air heater inlet was consistently greater than the guarantee of 2 ppmvd {at} 3% O{sub 2}. As a result, additional testing was performed on May 30-June 1 and on June 20-21, 2007, in conjunction with tuning of the hybrid NO{sub x} control system by BPEI, in an effort to achieve the performance target for ammonia slip. This additional testing occurred after the installation of a large particle ash (LPA) screen and removal system just above the SCR reactor and a fresh SCR catalyst layer in mid-May. This report describes the results of the additional tests. During the May 30-June 1 sampling period, CONSOL R&D and Clean Air Engineering (CAE) each measured flue gas ammonia concentrations at the air heater inlet, downstream of the in-duct SCR reactor. In addition, CONSOL R&D measured flue gas ammonia concentrations at the economizer outlet, upstream of the SCR reactor, and CAE measured flue gas NO{sub x} and CO concentrations at the sampling grids located at the inlet and outlet of the SCR reactor. During the June 20-21 sampling period, CONSOL R&D measured flue gas ammonia concentrations at the air heater inlet. All ammonia measurements were performed using a modified version of U.S. Environmental Protection Agency (EPA) Conditional Test Method (CTM) 027. The NO{sub x} and CO measurements were performed using U.S. EPA Methods 7E and 10, respectively
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Guarantee Testing Results from the Greenidge Mult-Pollutant Control Project
CONSOL Energy Inc. Research & Development (CONSOL R&D) performed flue gas sampling at AES Greenidge to verify the performance of the multi-pollutant control system recently installed by Babcock Power Environmental Inc. (BPEI) on the 107-megawatt (MW) Unit 4 (Boiler 6). The multi-pollutant control system includes combustion modifications and a hybrid selective non-catalytic reduction (SNCR)/induct selective catalytic reduction (SCR) system to reduce NO{sub x} emissions, followed by a Turbosorp{reg_sign} circulating fluidized bed dry scrubber system and baghouse to reduce emissions of SO{sub 2}, SO{sub 3}, HCl, HF, and particulate matter. Mercury removal is provided via the co-benefits afforded by the in-duct SCR, dry scrubber, and baghouse and by injection of activated carbon upstream of the scrubber, as required. Testing was conducted through ports located at the inlet and outlet of the SCR reactor to evaluate the performance of the hybrid NO{sub x} control system, as well as through ports located at the air heater outlet and baghouse outlet or stack to determine pollutant removal efficiencies across the Turbosorp{reg_sign} scrubber and baghouse. Data from the unit's stack continuous emission monitor (CEM) were also used for determining attainment of the performance targets for NO{sub x} emissions and SO{sub 2} removal efficiency
Development of a multivariable risk model integrating urinary cell DNA methylation and cell-free RNA data for the detection of significant prostate cancer
Background: Prostate cancer exhibits severe clinical heterogeneity and there is a critical need for clinically implementable tools able to precisely and noninvasively identify patients that can either be safely removed from treatment pathways or those requiring further follow up. Our objectives were to develop a multivariable risk prediction model through the integration of clinical, urine-derived cell-free messenger RNA (cf-RNA) and urine cell DNA methylation data capable of noninvasively detecting significant prostate cancer in biopsy naïve patients. Methods: Post-digital rectal examination urine samples previously analyzed separately for both cellular methylation and cf-RNA expression within the Movember GAP1 urine biomarker cohort were selected for a fully integrated analysis (n = 207). A robust feature selection framework, based on bootstrap resampling and permutation, was utilized to find the optimal combination of clinical and urinary markers in a random forest model, deemed ExoMeth. Out-of-bag predictions from ExoMeth were used for diagnostic evaluation in men with a clinical suspicion of prostate cancer (PSA ≥ 4 ng/mL, adverse digital rectal examination, age, or lower urinary tract symptoms). Results: As ExoMeth risk score (range, 0-1) increased, the likelihood of high-grade disease being detected on biopsy was significantly greater (odds ratio = 2.04 per 0.1 ExoMeth increase, 95% confidence interval [CI]: 1.78-2.35). On an initial TRUS biopsy, ExoMeth accurately predicted the presence of Gleason score ≥3 + 4, area under the receiver-operator characteristic curve (AUC) = 0.89 (95% CI: 0.84-0.93) and was additionally capable of detecting any cancer on biopsy, AUC = 0.91 (95% CI: 0.87-0.95). Application of ExoMeth provided a net benefit over current standards of care and has the potential to reduce unnecessary biopsies by 66% when a risk threshold of 0.25 is accepted. Conclusion: Integration of urinary biomarkers across multiple assay methods has greater diagnostic ability than either method in isolation, providing superior predictive ability of biopsy outcomes. ExoMeth represents a more holistic view of urinary biomarkers and has the potential to result in substantial changes to how patients suspected of harboring prostate cancer are diagnosed
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Convergence of Prognostic Gene Signatures Suggests Underlying Mechanisms of Human Prostate Cancer Progression.
The highly heterogeneous clinical course of human prostate cancer has prompted the development of multiple RNA biomarkers and diagnostic tools to predict outcome for individual patients. Biomarker discovery is often unstable with, for example, small changes in discovery dataset configuration resulting in large alterations in biomarker composition. Our hypothesis, which forms the basis of this current study, is that highly significant overlaps occurring between gene signatures obtained using entirely different approaches indicate genes fundamental for controlling cancer progression. For prostate cancer, we found two sets of signatures that had significant overlaps suggesting important genes (p < 10-34 for paired overlaps, hypergeometrical test). These overlapping signatures defined a core set of genes linking hormone signalling (HES6-AR), cell cycle progression (Prolaris) and a molecular subgroup of patients (PCS1) derived by Non Negative Matrix Factorization (NNMF) of control pathways, together designated as SIG-HES6. The second set (designated SIG-DESNT) consisted of the DESNT diagnostic signature and a second NNMF signature PCS3. Stratifications using SIG-HES6 (HES6, PCS1, Prolaris) and SIG-DESNT (DESNT) classifiers frequently detected the same individual high-risk cancers, indicating that the underlying mechanisms associated with SIG-HES6 and SIG-DESNT may act together to promote aggressive cancer development. We show that the use of combinations of a SIG-HES6 signature together with DESNT substantially increases the ability to predict poor outcome, and we propose a model for prostate cancer development involving co-operation between the SIG-HES6 and SIG-DESNT pathways that has implication for therapeutic design
Scaling of the F_2 structure function in nuclei and quark distributions at x>1
We present new data on electron scattering from a range of nuclei taken in
Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the
cross section for , which is sensitive to short range contributions to the
nuclear wave-function, and in deep inelastic scattering corresponds to probing
extremely high momentum quarks. This result agrees with higher energy muon
scattering measurements, but is in sharp contrast to neutrino scattering
measurements which suggested a dramatic enhancement in the distribution of the
`super-fast' quarks probed at x>1. The falloff at x>1 is noticeably stronger in
^2H and ^3He, but nearly identical for all heavier nuclei.Comment: 5 pages, 4 figures, to be submitted to physical revie
New measurements of high-momentum nucleons and short-range structures in nuclei
We present new measurements of electron scattering from high-momentum
nucleons in nuclei. These data allow an improved determination of the strength
of two-nucleon correlations for several nuclei, including light nuclei where
clustering effects can, for the first time, be examined. The data also include
the kinematic region where three-nucleon correlations are expected to dominate.Comment: 5 pages, 3 figures. Results from JLab E02-01
A controlled evaluation of an enhanced self-directed behavioural family intervention for parents of children with conduct problems in rural and remote areas.
Few studies have examined the impact of parenting interventions for families in rural and isolated areas who have children with conduct problems, where-access to professional services can be difficult. The present investigation compared the effects of three conditions, two levels of self-directed behavioral family intervention: an enhanced self-directed program that combined a self-help program using written materials and a weekly telephone consultation (ESD), a self-help program (SD) and a waitlist control group (WL). At postintervention the ESD group reported significantly lower levels of disruptive behaviour, and lower levels of dysfunctional parenting than the SD and WL controls, and higher levels of consumer satisfaction. At 6 months follow-up the main effects for the ESD group had been maintained. The SD group continued to evidence improvement from postintervention to follow-up such that 65% of children in the ESD condition and 57% of children in the SD condition showed clinical reliable change on measures of disruptive behaviour. Implications of findings and directions for future research are discussed
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Multi-ancestry study of blood lipid levels identifies four loci interacting with physical activity.
Many genetic loci affect circulating lipid levels, but it remains unknown whether lifestyle factors, such as physical activity, modify these genetic effects. To identify lipid loci interacting with physical activity, we performed genome-wide analyses of circulating HDL cholesterol, LDL cholesterol, and triglyceride levels in up to 120,979 individuals of European, African, Asian, Hispanic, and Brazilian ancestry, with follow-up of suggestive associations in an additional 131,012 individuals. We find four loci, in/near CLASP1, LHX1, SNTA1, and CNTNAP2, that are associated with circulating lipid levels through interaction with physical activity; higher levels of physical activity enhance the HDL cholesterol-increasing effects of the CLASP1, LHX1, and SNTA1 loci and attenuate the LDL cholesterol-increasing effect of the CNTNAP2 locus. The CLASP1, LHX1, and SNTA1 regions harbor genes linked to muscle function and lipid metabolism. Our results elucidate the role of physical activity interactions in the genetic contribution to blood lipid levels
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