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Catalytic combustion systems represent a potentially significant technology development in low-NOx gas turbine technology. The challenges associated with the implementation of catalytic combustion in a gas turbine include the need to present both a uniform fuel/air mixture as well as a uniform approach velocity to the catalyst within a minimal volume. The effort described herein addresses the design of catalytic combustor premixer for use on a small frame industrial (5 MW) stationary gas turbine. The general requirements for the premixer were to provide velocity and fuel air mixture uniformity at the exit plane of ±10% of the mean and ±3% of the mean respectively at nominal idle and full load conditions while maintaining a pressure drop of 4% maximum. The target turbine's packaging and air-flow path presented an additional challenge requiring the flow to make a 180 degree flow reversal immediately upstream of the combustor. Computational fluid dynamics modeling was. utilized to iterate the mixer design. A unique solution was obtained utilizing an involute shaped contraction/throat/expansion scheme. The most promising design was fabricated and tested at atmospheric conditions. As compared to a "baseline" mixer, the final involute design improved upon the flow mixing and velocity uniformity. The novel premixer design also eliminated the use of fuel injection spokes and static mixers, relying upon fuel injection from the wall and a high turbulent kinetic energy (TKE) throat section to provide the mixing, thereby simplify manufacturing. To test both scaling issues in the mixer and to provide an opportunity to test the design at high pressure, a 25% scale (approximate) reduced size mixer was designed and fabricated. Subsequent atmospheric and elevated pressure (11 atm, 1110 kPa) testing confirmed that the mixture uniformity was maintained and the general concept was applicable at both a reduced scale and at elevated pressures. Finally the premixer was integrated with a catalyst and fueled to confirm the overall system performance. The emissions of NOx were

A comprehensive field data collection campaign is reported on in which operational data are being obtained from microturbine generators located in the South Coast Air Quality Management District (AQMD). The data obtained are archived in a SQL database, which provides the ability to look at various performance aspects as a function of many parameters interactively on the Internet. An overview of the program is provided along with details regarding the data collection and archiving strategies. To provide a framework relative to optimal operation of these systems in the region, economics associated with various operational schedules as a function of various rate structures in Southern California are provided. In addition to quantitative operational characteristics and performance results, some general end-user impressions of the technology and of the overall installation process are also documented. Details from three representative sites are presented.

Soot samples were extracted from a swirl-stabilized, liquid-fuel fired laboratorycombustor to (i) assess the validity of the ASTM smoke point test in predicting thesooting characteristics of fuels in complex combustion systems and (ii) assess theeffect of fuel molecular structure and smoke suppressant additives on the physicaland chemical properties of soot. Fuels utilized were shale JP-8, iso-octane, andblends of iso-octane with either decalin, toluene, tetralin, or 1-methylnaphthalenesuch that smoke points similar to JP-8 were achieved. Each fuel was separatelyblended with 0.05 percent (by weight) ferrocene smoke suppressant. The resultsindicate that the ASTM test can be misleading, increased fuel molecular complexityincreases soot content of higher molecular weight polycyclic aromatics, andferrocene additive reduces small particle number density but not necessarily the sootmass loading. © 1984 by ASME.

In-flame measurements of soot particulate using conventional extractive and nonintrusive optical probes are compared for a swirl-stabilized combustor. Except for large (approximately 5 mu m) particulate present in the extracted samples, the soot particle size compares favorably with optically measured values, and the soot particle morphology reflects that formed in gas turbine combustors. Two, nonflame sources for the large particulate are suggested by the optical data: particles formed or elongated during transport subsequent to extraction, and particles attrited from upstream carbon deposits on a solid surface. The extractive probe produces a change in the local particle number density which varies from little change to a 70-fold suppression in reacting flow and a 200-fold increase in cold seeded flow depending on the location within the combustor of the optical sampling volume, the location of the extractive probe relative to the optical sampling volume, and the combustor operating conditions.

Alcohol use disorder (AUD) is defined as the impaired ability to stop or control alcohol use despite adverse social, occupational, or health consequences and still represents one of the biggest challenges for society regarding health conditions, social consequences, and financial costs, including the high relapse rates after traditional alcohol rehabilitation treatment. Especially, the deficient emotional competence in AUD is said to play a key role in the development of AUD and hinders the interruption of substance compulsion, often leading to a viscous circle of relapse. Although the empirical evidence of a neurophysiological basis of AUD is solid and increases even further, clinical interventions based on neurophysiology are still rare for individuals with AUD. This randomized controlled trial investigates changes in emotional competences, alcohol-related cognitions, and drinking behavior before and after an established alcohol rehabilitation treatment (control group: nCG = 29) compared to before and after an optimized, add-on neurofeedback (NF) training (experimental group: nEG = 27). Improvements on the clinical-psychological level, i.e. increases in emotional competences as well as life satisfaction, were found after the experimental electroencephalography (EEG) NF training. Neurophysiological measurements via resting-state EEG indicate decreases in low beta frequency band, while alpha and theta bands remained unaffected., (© The Author(s) 2024. Published by Oxford University Press.)

Evidence has accumulated that emotion recognition performance varies with menstrual cycle phase. However, according to some empathy models, facial affect recognition constitutes only one component of empathic behavior, besides emotional perspective taking and affective responsiveness. It remains unclear whether menstrual cycle phase and thus estradiol and progesterone levels are also associated with the two other empathy constructs. Therefore, we investigated 40 healthy right-handed females, 20 during their follicular phase and 20 during their midluteal phase and compared their performance in three tasks tapping the empathic components as well as self-report data. Salivary hormone levels were obtained and correlated with performance parameters. Subjects were matched for age and education and did not differ in neuropsychological function. Analysis of empathy performance revealed a significant effect of phase in emotion recognition, showing higher accuracy in the follicular group. Regarding affective responsiveness, we observed a significant difference in reaction times, with faster responses for sad and angry stimuli in the midluteal group. No significant group difference emerged for emotional perspective taking. Furthermore, significant correlations between progesterone levels and emotion recognition accuracy and affective responsiveness emerged only in the luteal group. However, groups did not differ in self-reported empathy. Our results indicate that menstrual cycle phase and thus ovarian hormone concentration are differentially related to empathic behavior, particularly emotion recognition and responsiveness to negative situations, with progesterone covarying with both in the luteal phase., (Copyright © 2012 Elsevier Inc. All rights reserved.)