A survey of gas-side fouling in industrial heat-transfer equipment

Gas-side fouling and corrosion problems occur in all of the energy intensive industries including the chemical, petroleum, primary metals, pulp and paper, glass, cement, foodstuffs, and textile industries. Topics of major interest include: (1) heat exchanger design procedures for gas-side fouling service; (2) gas-side fouling factors which are presently available; (3) startup and shutdown procedures used to minimize the effects of gas-side fouling; (4) gas-side fouling prevention, mitigation, and accommodation techniques; (5) economic impact of gas-side fouling on capital costs, maintenance costs, loss of production, and energy losses; and (6) miscellaneous considerations related to gas-side fouling. The present state-of-the-art for industrial gas-side fouling is summarized by a list of recommendations for further work in this area

Oxygen production using solid-state zirconia electrolyte technology

High purity oxygen is required for a number of scientific, medical, and industrial applications. Traditionally, these needs have been met by cryogenic distillation or pressure swing adsorption systems designed to separate oxygen from air. Oxygen separation from air via solid-state zirconia electrolyte technology offers an alternative to these methods. The technology has several advantages over the traditional methods, including reliability, compactness, quiet operation, high purity output, and low power consumption

Apparatus in the form of a disk for the separation of oxygen from other gases and/or for the pumping of oxygen and the method of removing the oxygen

An apparatus in the form of a disk for the separation of oxygen from gases, or for the pumping of oxygen, uses a substantially circular disk geometry for the solid electrolyte with radial flow of gas from the outside edge of the disk to the center of the disk. The reduction in available surface area as the gas flows toward the center of the disk reduces the oxygen removal area proportionally to provide for a more uniform removal of oxygen

Development of a Regional Fence Model with Implications for Wildlife Management

Barbed and woven wire fence are ubiquitous features across much of western North America, yet their effects on wildlife have received less attention than those of other anthropogenic features. At this time, no geospatial fencing data is available at broad level scales; potentially making wildlife modeling of vagile species less accurate and conservation planning less reliable at various scales. Here, we model fence density across 13 counties in Montana’s Hi-Line region, based on publicly available GIS data and assumptions created from local, expert knowledge. The resulting fence location and density GIS layers are based on assumptions about where fence locations occur in association to different types of land tenure, land cover and roads. Locations of fences were collected via GPS along random 3.2 km long road transects (n = 738) to assess overall model accuracy. Using a confusion matrix to determine variation between field and modeled fence locations, the total accuracy of the model was 73% and Kappa was .40. Although we found inaccuracies associated with large parcels (>3 contiguous sections) of cultivated agriculture, our model is a promising step towards delineating fencing across the west. These general rules may be used and refined in the other areas based on the regional historical context. This new data may advance both wildlife research and management/mitigation activities. Using the relative density of fences across a region can prioritize conservation efforts at this broad scale. In addition, modeled fence locations provide useful and accurate information at a local scale

Method of producing ceramic distribution members for solid state electrolyte cells

A solid state electrolyte cells apparatus and method of producing is disclosed. The apparatus can be used for separating oxygen from an oxygen-containing feedstock or as a fuel cell for reacting fluids. Cells can be stacked so that fluids can be introduced and removed from the apparatus through ceramic distribution members having ports designed for distributing the fluids in parallel flow to and from each cell. The distribution members can also serve as electrodes to membranes or as membrane members between electrodes, The distribution member design does not contain any horizontal internal ports which allows the member to be thin. A method of tape casting in combination with an embossing method allows intricate radial ribs and bosses to be formed on each distribution member. The bosses serve as seals for the ports and allow the distribution members to be made without any horizontal internal ports

Ceramic distribution members for solid state electrolyte cells and method of producing

A solid state electrolyte cells apparatus and method of producing is disclosed. The apparatus can be used for separating oxygen from an oxygen-containing feedstock or as a fuel cell for reacting fluids. Cells can be stacked so that fluids can be introduced and removed from the apparatus through ceramic distribution members having ports designed for distributing the fluids in parallel flow to and from each cell. The distribution members can also serve as electrodes to membranes or as membrane members between electrodes. The distribution member design does not contain any horizontal internal ports which allows the member to be thin. A method of tape casting in combination with an embossing method allows intricate radial ribs and bosses to be formed on each distribution member. The bosses serve as seals for the ports and allow the distribution members to be made without any horizontal internal ports

Caribou and reindeer migrations in the changing Arctic

Caribou and reindeer, Rangifer tarandus, are the most numerous and socio-ecologically important terrestrial species in the Arctic. Their migrations are directly and indirectly affected by the seasonal nature of the northernmost regions, human development and population size; all of which are impacted by climate change. We review the most critical drivers of Rangifer migration and how a rapidly changing Arctic may affect them. In order to conserve large Rangifer populations, they must be allowed free passage along their migratory routes to reach seasonal ranges. We also provide some pragmatic ideas to help conserve Rangifer migrations into the future. Barrier effect, Climate change, Connectivity, Conservation, Development, Mitigation, RangiferpublishedVersio

Variability in the Selection Patterns of Pronghorn: Are they Really Native Prairie Obligates?

In Canada, pronghorn (Antilocapra americana) are primarily considered a native prairie obligate because of their reliance on open grassland vegetation communities, although an assessment of local ecological knowledge suggests that pronghorn in Alberta select a variety of habitat from native prairie to cultivated lands. The primary objective of our study was to assess whether pronghorn in Alberta and Saskatchewan are native prairie obligates. Specifically, we addressed the following questions: 1) do individual pronghorn show similar selection patterns for native prairie and, therefore, support the notion that they are prairie obligates; 2) do pronghorn show consistent resource selection patterns at multiple scales (landscape and within-seasonal range); and 3) to what extent are selection patterns of pronghorn influenced by highways and roads. Within Alberta, we captured, collared, and monitored for one year individual female pronghorn in December 2003 (n = 24), March 2005 (n = 25), and March 2006 (n = 25). A detrended correspondence analysis of patterns of habitat selection revealed three distinct groups of pronghorn (r2 = 0.96, n = 55) that we labeled native, cultivated, and mixed, referring to the dominant land cover in their parturition ranges. We used logistic regression to model resource selection patterns of the three groups of pronghorn during the parturition and winter periods at the landscape and within-seasonal range scales. At the landscape scale, each group of pronghorn had top models consisting of the variables land cover, landform, distance to express highways, distance to arterial roads, and distance to collector roads for both periods. The native and mixed groups were less likely to use annual and perennial cropland than native prairie habitats, whereas the cultivated group was more likely to use annual and perennial cropland. At the within-seasonal range scale, the top models for each group in both seasons consisted of one or more road variables, but the top models exhibited poor model fit. Our results do not show a clear association for native prairie, which we would have expected if pronghorn were native prairie obligates, suggestive of plasticity in behavior. We acknowledge that patterns of habitat selection do not indicate habitat quality or fitness; therefore, to understand the individual- and population-level consequences of selecting sub-optimal habitats, such as agricultural landscapes, further research is needed

Prodigal Children: Why Older Mothers Favor Their Once-Deviant Adult Children

Objectives Past research suggests that adult children who reform their deviant behaviors (i.e., problems with drugs/alcohol or the law) are more likely to become favored by their mothers, yet the reasons underlying this phenomenon are unclear. This study employs a longitudinal, qualitative approach to explore why adult children’s behavioral reforms shape changes in maternal favoritism. Methods Analyses are based on qualitative interview data collected at two points seven years apart from older mothers regarding their adult children in 20 families. Each of these families had a “prodigal child”—a child for whom desistance from deviant behaviors between the two waves was accompanied by newfound maternal favoritism. Results Findings revealed two conditions under which mothers came to favor reformed deviants over their siblings. First, this occurred when adult children’s behavioral reformations were accompanied by mothers’ perceptions of these children as having grown more family-oriented. Second, this occurred when mothers came to see reformed deviants as exhibiting a stronger need and appreciation for maternal support, relative to their siblings. Discussion Mothers’ perceptions of children’s behavioral reformations as being accompanied by greater dedication to family or reflecting a need for their mothers’ support offer two explanations for why previously deviant adult children may become mothers’ favored offspring. These findings contribute to a growing body of scholarship on the complexity of intergenerational relations by shedding new light on changing patterns of favoritism in families with a history of parental disappointment, conflict, and strain

Redressing Inequity in Parent Care Among Siblings

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72515/1/j.1741-3737.2003.00201.x.pd