Dry Gas Seal (DGS) Separation Seal Failure

Case StudiesThis case study presents the failures experienced on separation seals installed on several compressors. The failures resulted in oil migration to the dry gas seals. Segmented contact-type carbon ring bushing separation seals were installed in multiple compressors in an ethylene plant. It was observed that the secondary drain was collecting oil after a few months of operation in spite of maintaining the optimum N2 supply pressure for the separation seals. Subsequent inspection of the dry gas seals confirmed oil ingress into the secondary seals which led to contact between seal faces. Excessive wear on the separation seal carbon bushings was also observed. Failure analysis was performed and root cause identified. Various solutions were studied and some preliminary design changes were implemented in the seals. However these changes did not improve the oil migration issue. Further site evaluation combined with OEM support resulted in implementation of two design changes which have effectively mitigated the oil migration. This case study will present the problems encountered, root causes analyzed, solutions implemented, learnings and the results after 4 years of operation

Study of the immediate short term clinical and radiological outcome of intertrochanteric neck of femur fractures treated with primary bipolar hemiarthroplasty in geriatric population in a tertiary care centre

Background: Intertrochanteric fracture in elderly patient is a frequent problem and is becoming more common as the proportion of elderly people in the population increases. Unstable intertrochanteric fracture in the elderly patient is associated with a high rate of mortality as much as 20 percent during the first postoperative year. The treatment of such unstable intertrochanteric fracture is still controversial. So as to allow for earlier postoperative weight-bearing, primary hemiarthroplasty was proposed by some authors. The purpose of this study is to evaluate the functional and clinical outcomes of cemented bipolar arthroplasty as a primary treatment for unstable intertrochanteric fracture in the elderly patient.Methods: It was an observational retrospective plus prospective study design over a period of 18 months in a tertiary care setting with a sample size of 41. Patients fulfilling the inclusion criteria were assessed clinically using Harris hip score and radiologically were operated for bipolar hemiarthroplasty. They were assessed intraoperatively, immediate postoperatively and after 4 weeks for functional outcome using Harris hip score and assessed radiologically. Patients were also be evaluated for intraoperative and postoperative complications if any. The outcome was analysed statistically to comment on functional outcome of bipolar hemiarthroplasty.Results: In our study majority of the patients 70% (29) had excellent and good outcomes at the end of 1 month. Out of the rest 22% more had fair outcome at the end of month. Thus 93% patients had favorable outcomes at the end of 1 month while 7% (3 cases) had poor outcome when measured using Harris hip score.Conclusions: Primary cemented bipolar hemiarthroplasty is a viable option that leads to good functional outcomes and allows early mobilization and weight bearing

An Automated Method for Rapid Identification of Putative Gene Family Members in Plants

BACKGROUND: Gene duplication events have played a significant role in genome evolution, particularly in plants. Exhaustive searches for all members of a known gene family as well as the identification of new gene families has become increasingly important. Subfunctionalization via changes in regulatory sequences following duplication (adaptive selection) appears to be a common mechanism of evolution in plants and can be accompanied by purifying selection on the coding region. Such negative selection can be detected by a bias toward synonymous over nonsynonymous substitutions. However, the process of identifying this bias requires many steps usually employing several different software programs. We have simplified the process and significantly shortened the time required by condensing many steps into a few scripts or programs to rapidly identify putative gene family members beginning with a single query sequence. RESULTS: In this report we 1) describe the software tools (SimESTs, PCAT, and SCAT) developed to automate the gene family identification, 2) demonstrate the validity of the method by correctly identifying 3 of 4 PAL gene family members from Arabidopsis using EST data alone, 3) identify 2 to 6 CAD gene family members from Glycine max (previously unidentified), and 4) identify 2 members of a putative Glycine max gene family previously unidentified in any plant species. CONCLUSION: Gene families in plants, particularly that subset where purifying selection has occurred in the coding region, can be identified quickly and easily by integrating our software tools and commonly available contig assembly and ORF identification programs

An automated method for rapid identification of putative gene family members in plants

This study has simplified the gene family identification process by automating the various steps and developing the applications SimESTs, PCAT, SCAT, and has significantly reduced the time taken for identifying gene families from ESTs. One can quickly identify the gene families in plants that exhibit a purifying selection between members. In addition, the applications have been used to test the quality of the clusters produced by existing clustering algorithms such as Unigene --Abstract, page iii

BIOSYNTHESIS OF GOLD NANOPARTICLES FROM FUNGI

All selected five fungi Colletotrichum fulcatum, Trichoderma atroviride, Aspergillus paraciticus. Aspergillus carbonarius and Penicillium citrinum are used for the biosynthesis of gold nanoparticles fresh cell-free filtrate was used for the synthesis of gold nanoparticles. chloroauric acid was the reductant agent mixed with cell-free filtrate of fungi. During the visible analysis, Aspergillus paraciticus biomass was changed from pale yellow to purple color, in Aspergillus carbonarius biomass was changed from black color to Purple and Penicillium citrinum pale brown color to brown color and UV-Visible spectroscopic analysis. In UV-visible spectrum, no peak formation was observed in cell-free extract Colletotrichum fulcatum, Trichoderma atroviride, Aspergillus paraciticus, Aspergillus carbonarius, and Penicillium citrinum before immersion of HAuCl4 in series 3 and 4, while as strong surface plasmon resonance (SPR) peak of the cell-free extract with HAuCl4 was observed at 450 and 550 nm

DESIGN AND FABRICATION OF DUAL AXIS SOLAR TRACKER FOR MAXIMUM ENERGY HARVESTING

Now-a-days we are using static solar panels but this system does not give maximum harvesting of solar energy. In this project, we are presenting the hardware design and implementation of Dual Axis Solar Tracking System that ensures a perpendicular profile of the solar panel with the sun in order to extract maximum energy falling on it. The LDRs do the job of sensing the change in the position of the sun which is dealt by the respective change in the solar panel’s position by switching on and off the DC geared motor. With the implementation of the proposed system the additional energy generated is greater than conventional system with very less consumption by the system itself

Visible-Solar-Light-Driven Photocatalytic Degradation of Phenol with Dye-Sensitized TiO2: Parametric and Kinetic Study

Phenol degradation with TiO2 photocatalyst under UV light is known to be an effective method. Under solar radiation, however, this approach does not receive adequate photons for catalyst activation, as the solar spectrum comprises mostly visible light (46%). In this study, we applied the dye-sensitization technique to prepare visible-light-active catalyst and used it under visible solar light generated from a solar simulator with a UV cutoff filter (λ \u3e 420 nm) for phenol degradation. Eosin Y dye was used as a sensitizer for the TiO2 catalyst with a very low level of platinum as a cocatalyst. Triethanolamine was used as a sacrificial electron donor. Parametric studies were performed for the catalyst loading, initial triethnolamine concentration, initial phenol concentration, platinum content on TiO2, solution pH, and visible light intensity. About 93% degradation of 40 ppm phenol solution was achieved within 90 min using Eosin Y−TiO2/Pt photocatalyst under optimum conditions (pH 7.0, catalyst loading of 0.8 g/L, triethnolamine concentration of 0.2 M, 0.5% Pt loading on TiO2, visible solar light intensity of 100 mW/cm2). The kinetic rate constant and adsorption equilibrium constant were determined, and a Langmuir−Hinshelwood-type equation was proposed to describe phenol degradation on TiO2 at different visible light intensities. The model equation was found to predict the experimental results quite well