258 research outputs found
Operational reliability assessment of the GEOS A spacecraft
Decision theory application to GEOS A spacecraft operational reliability assessmen
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Chemically modified coal macerals. Separation, density and surface area variations
Two Argonne Premium Coals were O-alkylated and O-acylated using a variety of different reagents, and then separated using density gradient centrifugation (ADGC). The separation data suggested that the hydroxyl groups are fairly evenly distributed in the maceral particles. However, several reagents produced results counter to this generalization, and exhibited enhanced maceral separation. Comparison of ADGC densities and He densities of the modified coals showed several reactivity families that appear to be based on wettability differences. Surface areas were also measured; areas as high as 200 m{sup 2}/g were obtained for some modified coals. The data suggest that there is an optimum molecular size for the added group that leads to the large areas
Quantum resonances in selective rotational excitation of molecules with a sequence of ultrashort laser pulses
We investigate experimentally the effect of quantum resonance in the
rotational excitation of the simplest quantum rotor - a diatomic molecule. By
using the techniques of high-resolution femtosecond pulse shaping and
rotational state-resolved detection, we measure directly the amount of energy
absorbed by molecules interacting with a periodic train of laser pulses, and
study its dependence on the train period. We show that the energy transfer is
significantly enhanced at quantum resonance, and use this effect for
demonstrating selective rotational excitation of two nitrogen isotopologues, and . Moreover, by tuning the period of the pulse train in
the vicinity of a fractional quantum resonance, we achieve spin-selective
rotational excitation of para- and ortho-isomers of .Comment: 5 pages, 4 figure
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Geothermal direct use engineering and design guidebook
The Geothermal Direct Use Engineering and Design Guidebook is designed to be a comprehensive, thoroughly practical reference guide for engineers and designers of direct heat projects. These projects could include the conversion of geothermal energy into space heating cooling of buildings, district heating, greenhouse heating, aquaculture and industrial processing. The Guidebook is directed at understanding the nature of geothermal resources and the exploration of these resources, fluid sampling techniques, drilling, and completion of geothermal wells through well testing, and reservoir evaluation. It presents information useful to engineers on the specification of equipment including well pumps, piping, heat exchangers, space heating equipment, heat pumps and absorption refrigeration. A compilation of current information about greenhouse, aquaculture and industrial applications is included together with a discussion of engineering cost analysis, regulation requirements, and environmental considerations. The purpose of the Guidebook is to provide an integrated view for the development of direct use projects for which there is a very potential in the United States
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Determination of sulfur compounds in coal by mass spectrometry, correlated with XANES and XPS
The objective of this study is to identify important organic sulfur-containing compounds in the Argonne Premium Coals and in selected, separated coal macerals. In-source, desorption/pyrolysis high resolution mass spectrometry is being used to characterize the volatile species of whole coals, macerals, and their extracts. To examine the possibility of secondary reactions and undesirable selectivity, the MS data is compared to data from direct techniques, XANES and XPS. The MS results con-elate very well which supports the suggestion that the species seen are indigenous to the original sample. Therefore, specific structural assignments to the sulfur species can be made. Quantitative speciation of organic sulfur in coals has been accomplished by both XANES and XPS with what appears to be good reliability. Mass spectrometry approaches provide more detailed molecular information, but suffer from problems with sampling. In the past we have found it difficult to isolate aliphatic sulfur compounds by thermal desorption or pyrolysis due to their thermal transformation to aromatic species. However, recently we have found that with in-source pyrolysis the occurrence of secondary reactions is reduced significantly. Results from both a selected setof the Argonne Premium Coal Samples and a set of three macerals from the Listen-Stockton coal (APCS 7) are discussed
Understanding Face and Shame: A Servant-Leadership and Face Management Model
Clergy can have a negative impact on churches and other individuals when they knowingly or unknowingly attempt to save face, that is, try to protect their standing or reputation. The desire to gain face and the fear of losing face and feeling ashamed will likely permeate clergy’s decision-making processes without even being noticed. This study explores the essence of face and face management and the relationship between face management and two characteristics of servant-leadership—awareness and healing—in both Chinese and American churches through the methodology of hermeneutic phenomenology. Prior to this study, to my knowledge, no hermeneutic phenomenological research of face management has been conducted in a church setting. Through a review of the literature, four areas are explored: face and shame, face management, servant-leadership, and face, shame, and face management within the church. This study obtained approval from the Institutional Review Board and informed consent from the participants. Three Chinese and three American Christian ministers were chosen to complete a question sheet and participate in two semi-structured interview sessions. A first cycle of open coding and second cycle of pattern coding were used during data analysis. Face experiences are discussed in light of eight major themes: body, triggers, becoming, face concepts, strategies, emotions, servant-leadership, and the church. Findings from the study help build a servant-leadership and face management model, which can offer an anchored approach for clergy and pastoral counselors to address face and shame and to develop therapeutic interventions
3D Airway changes using cone beam computed tomography in patients following mandibular advancement surgery with and without constriction
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149306/1/ocr12292.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149306/2/ocr12292_am.pd
The Probability of a Gene Tree Topology within a Phylogenetic Network with Applications to Hybridization Detection
Gene tree topologies have proven a powerful data source for various tasks, including species tree inference and species delimitation. Consequently, methods for computing probabilities of gene trees within species trees have been developed and widely used in probabilistic inference frameworks. All these methods assume an underlying multispecies coalescent model. However, when reticulate evolutionary events such as hybridization occur, these methods are inadequate, as they do not account for such events. Methods that account for both hybridization and deep coalescence in computing the probability of a gene tree topology currently exist for very limited cases. However, no such methods exist for general cases, owing primarily to the fact that it is currently unknown how to compute the probability of a gene tree topology within the branches of a phylogenetic network. Here we present a novel method for computing the probability of gene tree topologies on phylogenetic networks and demonstrate its application to the inference of hybridization in the presence of incomplete lineage sorting. We reanalyze a Saccharomyces species data set for which multiple analyses had converged on a species tree candidate. Using our method, though, we show that an evolutionary hypothesis involving hybridization in this group has better support than one of strict divergence. A similar reanalysis on a group of three Drosophila species shows that the data is consistent with hybridization. Further, using extensive simulation studies, we demonstrate the power of gene tree topologies at obtaining accurate estimates of branch lengths and hybridization probabilities of a given phylogenetic network. Finally, we discuss identifiability issues with detecting hybridization, particularly in cases that involve extinction or incomplete sampling of taxa
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