Development And Testing Of A Very High Speed Oil Lubricated End Face Mechanical Seal.

Case StudySix large radial inflow turbines were designed to expand isobutane for two electric power plants in Nevada which use heat from the earth (geothermal energy) as the energy source. Double end face mechanical seals lubricated by oil were selected to stop the isobutane from leaking out of the closed loop system and into the atmosphere. Two of the largest providers of mechanical seals in the world provided reference lists showing that this application was pushing the tip speed limits for existing liquid end face mechanical seals. A vendor was selected and the seals were purchased. The first run of the seals on the test stand seemed successful, until the disassembly of the unit revealed the faces were severely overheated and heat checked. The face design was changed and the second test was successful. A major concern was to maintain a low seal leakage rate, so this was measured and was within the specified range. However, the third test resulted in a catastrophic failure of the rotating faces and collateral damage to the entire seal cartridge. Detailed investigation of the failure revealed several interesting problem areas. All of these were addressed in a new design which was implemented, built, and shipped in only one week! The fourth test was successful, but still showed a problem in which the very high velocity oil in the seal chamber was able to dislodge the stationary face retaining ring. A solution to this final problem was implemented and tested successfully. At the time of this abstract, the seals appear to be successful. Both plants (all six machines) have been placed on line successfully. Two seals experienced damage in the field due to problems with the lube oil filter housings. These problems will be discussed during the presentation

The Grizzly, April 15, 1988

Greek Week\u27s Coming! • Sorority Songfest Sunday • Letters: Visser to Goofley: Kiss Dirt!; Code: Honor; Billing Miffs Student; Professor Nagy Responds to Tiryak Forum; Red Cross Congratulates UC Donators • Mid East Forum Scheduled • Take Women\u27s Studies! • 1988-89 RAs Announced • Men\u27s Track Races to 5-0 • LAX Hopes to Lift Level of Play Against West Chester • Women\u27s Outdoor Places Fourth • Baseball Hopes to Turn Season Around vs. Widener • Race-rafters Rollick • Underclassmen Pitching Power Carrying Softballers • Hallinger Takes Third • Strong Sailing for U.C. • The Grizzly\u27s Senior Sports Spotlight Salutes Kris Carr • Women Students Rule • Tommy Conwell in Concert Rumbles Ursinus • Portrait of an Artist • STAR Ambassadors Shinehttps://digitalcommons.ursinus.edu/grizzlynews/1211/thumbnail.jp

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Quantifying the impact of deprivation on preterm births:a retrospective cohort study

Background: Social deprivation is associated with higher rates of preterm birth and subsequent infant mortality. Our objective was to identify risk factors for preterm birth in the UK's largest maternity unit, with a particular focus on social deprivation, and related factors. Methodology/Principal Findings: Retrospective cohort study of 39,873 women in Liverpool, UK, from 2002-2008. Singleton pregnancies were stratified into uncomplicated low risk pregnancies and a high risk group complicated by medical problems. Multiple logistic regression, and generalized additive models were used to explore the effect of covariates including area deprivation, smoking status, BMI, parity and ethnicity on the risk of preterm birth (34(+0) weeks). In the low risk group, preterm birth rates increased with deprivation, reaching 1.6% (CI95 1.4 to 1.8) in the most deprived quintile; the unadjusted odds ratio comparing an individual in the most deprived quintile, to one in the least deprived quintile was 1.5 (CI95 1.2 to 1.9). Being underweight and smoking were both independently associated with preterm birth in the low risk group, and adjusting for these factors explained the association between deprivation and preterm birth. Preterm birth was five times more likely in the high risk group (RR 4.8 CI95 4.3 to 5.4), and there was no significant relationship with deprivation. Conclusions: Deprivation has significant impact on preterm birth rates in low risk women. The relationship between low socio-economic status and preterm births appears to be related to low maternal weight and smoking in more deprived groups

Proportion of PTB in low and high risk groups stratified by deprivation quintile.

<p>Proportion of PTB in low and high risk groups stratified by deprivation quintile.</p

Generalized additive model assessing the relationship between risk of preterm delivery<34 and deprivation score.

<p>Generalized additive model assessing the relationship between risk of preterm delivery<34 and deprivation score.</p

Prevalence of risk factors and outcomes in low and high risk cohorts.

<p>Prevalence of risk factors and outcomes in low and high risk cohorts.</p

Multivariate logistic regression models assessing independent association between covariates and PTB in low risk group.

<p>Multivariate logistic regression models assessing independent association between covariates and PTB in low risk group.</p

Pregnancies by deprivation quintile for LWH study sample 2002–2008 and all pregnancies in England 2004.

<p>Pregnancies by deprivation quintile for LWH study sample 2002–2008 and all pregnancies in England 2004.</p