Eliminating Oil Leaks By Optimizing Bearing Case Oil Labryinths.

LecturePg. 93-100Many pieces of rotating equipment experience oil leaks. Any piece of equipment with oil fed bearings, such as turbines, motors, gearboxes, and compressors, are susceptible to oil leaks from the bearing case seals. Usually these seals are of the labyrinth type and their designs have remained unchanged for years. Examination of this seal, the bearing case design, and the lube system can point to possible causes for leaks. Once it has been determined that system and installation problems have been addressed, it is time to evaluate the seal design. This paper presents an introduction to the causes of oil leaks and some items to consider with the lube system. Seal installation is covered, along with possible intermediate fixes and other topics. A more thorough discussion of the labyrinth oil seal is then included, covering existing design deficiencies and optimized seal design parameters. Case histories are presented, illustrating the points covered

A Development Evaluation Study of a Professional Development Initiative to Strengthen Organizational Conditions in Early Education Settings

High quality instruction is essential to producing developmental gains for young children and can mitigate risk factors such as family poverty and low parental education. Even in programs with highly qualified teachers, teacher-child interactions often do not provide the level of instructional support that children need to be well-prepared for success in kindergarten. In order to improve instructional quality, an emerging focus on early childhood professional development involves supporting leaders in creating a web of supports for teacher learning and child growth. The purpose of the 3-year evaluation study was to assess the effectiveness of an Early Childhood Education Professional Development Initiative (ECE PDI) in advancing the knowledge, skills, and dispositions of community-based early childhood leaders and teachers in relation to creating the conditions for superior developmental outcomes for low-income students served by these community-based centers. Findings from the implementation and impact studies are reported

Litter Controls Earthworm-Mediated Carbon and Nitrogen Transformations in Soil from Temperate Riparian Buffers

Nutrient cycling in riparian buffers is partly influenced by decomposition of crop, grass, and native tree species litter. Nonnative earthworms in riparian soils in southern Quebec are expected to speed the processes of litter decomposition and nitrogen (N) mineralization, increasing carbon (C) and N losses in gaseous forms or via leachate. A 5-month microcosm experiment evaluated the effect of Aporrectodea turgida on the decomposition of 3 litter types (deciduous leaves, reed canarygrass, and soybean stem residue). Earthworms increased CO2 and N2O losses from microcosms with soybean residue, by 112% and 670%, respectively, but reduced CO2 and N2O fluxes from microcosms with reed canarygrass by 120% and 220%, respectively. Litter type controlled the CO2 flux (soybean ≥ deciduous-mix litter = reed canarygrass > no litter) and the N2O flux (soybean ≥ no litter ≥ reed canarygrass > deciduous-mix litter). However, in the presence of earthworms, there was a slight increase in C and N gaseous losses of C and N relative to their losses via leachate, across litter treatments. We conclude that litter type determines the earthworm-mediated decomposition effect, highlighting the importance of vegetation management in controlling C and N losses from riparian buffers to the environment

Vermicompost as a fertilizer for urban and peri-urban farms: Perceptions of farmers in Accra, Ghana

Vermicompost is considered a valuable organic fertilizer in many tropical regions, but has rarely been used in sub-Saharan Africa. A study in Accra, Ghana, assessed urban and peri-urban (UP) farmers’ fertilizer and pesticide use, knowledge of earthworms, fertilizer performance criteria, and attitudes toward vermicompost as a fertilizer. Twenty-six farmers involved in irrigated vegetable farming and three subsistence farmers were interviewed. Farmers were aware that earthworm activity was associated with soil fertility, and some associated insecticide applications to reduced earthworm populations. Farmers used the greenness of leaves, crop emergence, stand and yield as indicators of fertilizer performance. Farmers resisted making statements about vermicompost before testing it, and advised that its fertilizer value be tested during the dry season. Farmers involved in irrigated vegetable farming had insufficient space and time for on-farm vermicomposting, while subsistence farmers lacked a reliable access to water necessary for on-farm vermicomposting; but both types of farmers were interested in adopting vermicompost if it improved crop performance. Such lack of farm resources suggest that a commercial facility would be best suited to produce vermicompost from organic waste, which would then be sold to farmers