27 research outputs found
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Ceramic vane demonstration in an industrial turbine
A DOE program with Allison Engine Co. will demonstrate ceramic vanes in an industrial turbine. First-stage ceramic vanes and metallic mounts are to be designed, fabricated, and operated in a short-term engine test (up to 50 hr). The vanes and mounts will then be retrofitted into an existing turbine for operation at a commercial site for up to 8000 hr. They have been designed. Thermal and stress analyses of the vanes have calculated acceptable fast fracture stress levels and probabilities of survival > 99.99% for turbine continuous power and emergency shutdown (thermal shock) conditions. Max calculated steady-state stress is 169 MPa at 1182 C, so currently available ceramics appear to provide acceptable fast fracture strengths for use in industrial turbines. Long-term materials test will evaluate the lifetimes and retained strength of ceramics at stress and temperature levels in the range calculated from the ceramic vane analyses. Results of these tests will support on which vane material will be used in the long duration turbine demonstration. A successful demonstration could provide a basis for incorporating first-stage ceramic vanes into current generation industrial turbines and also the introduction of ceramic airfoils into downstream rows of future high temperature Advanced Turbine System (ATS) engines
Ceramic Vane Demonstration in an Industrial Turbine
A DOE program with Allison Engine Co. will demonstrate ceramic vanes in an industrial turbine. First-stage ceramic vanes and metallic mounts are to be designed, fabricated, and operated in a short-term engine test (up to 50 hr). The vanes and mounts will then be retrofitted into an existing turbine for operation at a commercial site for up to 8000 hr. They have been designed. Thermal and stress analyses of the vanes have calculated acceptable fast fracture stress levels and probabilities of survival > 99.99% for turbine continuous power and emergency shutdown (thermal shock) conditions. Max calculated steady-state stress is 169 MPa at 1182 C, so currently available ceramics appear to provide acceptable fast fracture strengths for use in industrial turbines. Long-term materials test will evaluate the lifetimes and retained strength of ceramics at stress and temperature levels in the range calculated from the ceramic vane analyses. Results of these tests will support on which vane material will be used in the long duration turbine demonstration. A successful demonstration could provide a basis for incorporating first-stage ceramic vanes into current generation industrial turbines and also the introduction of ceramic airfoils into downstream rows of future high temperature Advanced Turbine System (ATS) engines
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DOE/Allison ceramic vane effort
This report describes the activities to be accomplished and the expected results from the program to develop ultra-high efficiency gas turbine systems. The topics of the report include the objectives, the approach, project description including design/analysis of ceramic vanes and mounting hardware; procurement of ceramic vanes; thermal shock proof tests; vane/mount proof test in engine; ceramic vane field demonstration, and expected results
Saree cancer: A diagnosis!
Saree cancer is a type of skin cancer that occurs along the waistline of Indian women wearing the traditional costume of ′saree′. The incidence of malignancy in scar tissues is 0.1-2.5%. Highly hypopigmented and thickened scars are more likely to progress into malignant lesions. Khanolkar and Suryabai described a new type of skin cancer - ′dhoti cancer′ in 1945. Persistent and long term use results in chronic friction/irritation in the region of waist which in term leads to waist-dermatosis
Optimal observable analysis for the decay b → s plus missing energy
Abstract The decay b → s ν ν ¯ has received comparatively less attention than the semileptonic decay b → s ℓ + ℓ - , because neutrinos pass undetected and hence the process offers lesser number of observables. We show how the decay b → s + invisible(s) can shed light, even with a limited number of observables, on possible new physics beyond the Standard Model and also show, quantitatively, the reach of future B factories like SuperBelle to uncover such new physics. Depending on the operator structure of new physics, different channels may act as the best possible probe. We show, using the optimal observable technique, how almost the entire parameter space allowed till now can successfully be probed at a high-luminosity B factory
Non-tuberculous mycobacterial soft tissue swelling in an immunocompetent patient
Non-tuberculosis mycobacteria (NTM) include those mycobacterium species that are not members of the Mycobacterium tuberculosis complex. They assumed significance with the growing pandemic of the acquired immune deficiency syndrome (AIDS) since the 1980s, when Mycobacterium avium infections were found to be associated with AIDS. However, the epidemiology of NTM disease among patients without Human immunodeficiency virus infections is not well documented. We report a case of NTM soft tissue swelling in an immunocompetent 18-year-old male who responded well to local excision and antitubercular treatment
Role of topical use of insulin in healing of chronic ulcer
Background : Chronic wounds, especially non-healing types, are one of the most common surgical conditions a surgeon comes across. The peculiarity of a chronic wound is that, whatever management you give, they refuse to heal, especially the pressure ulcers or bed sores. Many therapeutic methods are available to effect wound healing such as topical application of insulin, growth factors, negative pressure-assisted wound closure, oxidized regenerated cellulose/collagen, hyaluronic acid conjugated with glycidyl methacrylate or gelatin dressings. A less clinically and economically complicated approach to healing chronic wounds seems necessary.
Objectives: To study the efficacy of topical use of insulin in wound healing in following terms:-(1) rate of wound healing; (2) safety evaluation; (3) hospital stay. Materials and Methods: This was a prospective study carried out in a tertiary health centre from July 2010 to September 2012 in 50 patients after taking an informed and written consent of the patients having chronic ulcer. All the patients who were satisfying inclusion/exclusion criteria patient were randomized into two groups, Group A and Group B. Each group was again sub-divided into 1 and 2 i.e. sub-group A1, A2 and sub-group B1, B2. Patients with diabetes were grouped as A1 and B1 and non-diabetic patients were grouped as A2 and B2. Group A patients were treated with insulin dressings and Group B patient′s ulcers were treated with normal saline dressings. Ulcer size and healing was recorded on weekly basis. Strict glycemic control was maintained in all diabetic patients. Results were compared at complete healing or at the end of 12 weeks which ever was earlier. Results: Our study included both diabetic and non-diabetic patients. There was no significant change in BSL(R) values after use of insulin on wounds. The number of days required for wound healing in Group A patients in both subgroups (A1 and A2) was significantly less as compared to Group B (B1 and B2). The mean rate of healing of wounds was much faster in Group A as compared to Group B. The hospital stay in Group A patients was significantly less than Group B. Conclusion: The use of topical Insulin strongly suggests accelerated wound healing in chronic ulcer. Topical insulin in chronic ulcer is safe and effective without any systemic side effect. Topical insulin significantly reduces the hospital stay of patients with chronic ulcers. Early return to work decreased economical load
Early Enteral feeding within 24 hours of gastrointestinal surgery versus Nil by mouth: A prospective study
A prospective study on early enteral feeding v/s Nil by mouth was done on 74 patients in two groups. The study mainly focused on incidence of surgical site infection, post-operative complications, such as pulmonary complications, anastomotic leakage, abdominal distension, vomiting, and cost of treatment in both groups. It was observed that maximum patients in our study were in the age group of 31-40 years with male preponderance having an average of 12 gm % hemoglobin levels and average BMI of 23, which were divided in two groups. In our study, early enteral feeding has less incidence of surgical site infection with most infection by Klebsiella pneumonia in both groups, clinically less complications and less cost incurred. The incidence of vomiting was increased in early enteral fed group but did not lead to cessation of feeding. Early mobilization of patient and early establishment of bowel sounds are the other factors noticed in patients of early enteral fed groups in our study. Cost of treatment is emphasized in our study. Myth of patients keeping nil by mouth after surgery is to be discouraged. Early enteral feeding enhances recovery and can be safely given after all major gastrointestinal surgeries