Laboratory Evaluation of Microsurfacing Bond Strength

Author(s):  
Sk. Abu Talha ◽  
Ahmad Al-Hosainat ◽  
Munir D. Nazzal ◽  
Sang Soo Kim ◽  
Ala Abbas ◽  
...  
2010 ◽  
Vol 148-149 ◽  
pp. 449-452
Author(s):  
Jun Gu ◽  
Xin Hong Li ◽  
Hao Ya Liu ◽  
Yu Tang Gao

In order to solve the interlayer channeling in the process of oil and gas production, the forming agent of agglomerated cake and mud cake modifier based on Mud Cake to Agglomerated Cake (MTA) method are developed. The evaluation results in laboratory show that the bond strength of cement-formation interface (BSCFI) with the new materials increases significantly with curing time by comparison with those without new materials. The analysis shows that the mechanism of new materials includes three steps. Firstly, the forming agent of agglomerated cake modifies and treats the surface of mud cake and it reacts primarily with the mud cake modifier. Secondly, the cement generates in agglomerated cake. Lastly, the compact agglomerated cake forms. Field applications show that the high quality rate and qualified rate of well cementing with the new materials increased by 13.01 percent points and 1.15 percent points respectively, and the proportion of isolation section length whose Bond Index is greater or equal to 0.8 with the new materials increased by 15.92 percent points compared with other wells in the same block.


2010 ◽  
Vol 30 (03) ◽  
pp. 156-161 ◽  
Author(s):  
R. Gheisari ◽  
B. Bomke ◽  
T. Hoffmann ◽  
R. E. Scharf

SummaryWe have performed a monocenter study on 29 consecutive patients with acquired haemophilia A who were referred for diagnosis and treatment to the Düsseldorf Haemophilia Comprehensive Care Center between March 2001 and February 2010. Patients, methods: 18 men (age: 44–86 years) and 11 women (age: 20–83 years). For laboratory evaluation, a standardized staged protocol of aPTT, FVIII : C activity and concentration, mixing studies with patient and normal plasma, and quantification of inhibitor titers (Bethesda assay) was used. Diagnostic work-up included elaborate examinations for any underlying disease. Results: In 18 (62%) of the 29 patients with acquired haemophilia A, an underlying disorder was identified, including 9 patients with respiratory diseases (31%), 7 patients with autoimmune disorders (24%), one with malignancy, and one with postpartum state, while in 11 patients (38%) acquired haemophilia A remained idiopathic. Haemotherapy of bleeding, suppression or elimination of the inhibitor, and induction of immunotolerance to endogenous FVIII:C were performed according to a treatment algorithm. Predefined clinical endpoints were control of bleeding, eradication of the inhibitor, complete or partial remission (CR, PR), relapse, or early death (≤30 days). Of the 29 patients in total, 22 individuals achieved CR (76%), three had PR, one relapsed, and three died within 30 days (one of acute myocardial infarction while on anti-haemorrhagic treatment, one of sepsis while on immunosuppression due to active acquired haemophilia A, one of lung bleeding in association with pre-existing pulmonary sarcoidosis). Conclusion: This monocenter study demonstrates that control of life-threatening bleeding, eradication of the inhibitor, and induction of tolerance to endogenous FVIII have significantly improved the clinical outcome of acquired haemophilia A. Our data also suggest a shift in underlying disorders associated with acquired haemophilia A, whereby, in comparison to published studies, a relative increase in the proportion of patients with respiratory diseases is present.


1997 ◽  
Vol 77 (03) ◽  
pp. 444-451 ◽  
Author(s):  
José Mateo ◽  
Artur Oliver ◽  
Montserrat Borrell ◽  
Núria Sala ◽  
Jordi Fontcuberta ◽  
...  

SummaryPrevious studies on the prevalence of biological abnormalities causing venous thrombosis and the clinical characteristics of thrombotic patients are conflicting. We conducted a prospective study on 2,132 consecutive evaluable patients with venous thromboembolism to determine the prevalence of biological causes. Antithrombin, protein C, protein S, plasminogen and heparin cofactor-II deficiencies, dysfibrinoge-nemia, lupus anticoagulant and antiphospholipid antibodies were investigated. The risk of any of these alterations in patients with familial, recurrent, spontaneous or juvenile venous thrombosis was assessed. The overall prevalence of protein deficiencies was 12.85% (274/2,132) and antiphospholipid antibodies were found in 4.08% (87/2,132). Ten patients (0.47%) had antithrombin deficiency, 68 (3.19%) protein C deficiency, 155 (7.27%) protein S deficiency, 16 (0.75%) plasminogen deficiency, 8 (0.38%) heparin cofactor-II deficiency and 1 had dysfib-rinogenemia. Combined deficiencies were found in 16 cases (0.75%). A protein deficiency was found in 69 of 303 (22.8%) patients with a family history of thrombosis and in 205/1,829 (11.2%) without a history (crude odds ratio 2.34, 95% Cl 1.72-3.17); in 119/665 (17.9%) patients with thrombosis before the age of 45 and in 153/1,425 (10.7%) after the age of 45 (crude odds ratio 1.81, 95% Cl 1.40-2.35); in 103/616 (16.7%) with spontaneous thrombosis and in 171/1,516 (11.3%) with secondary thrombosis (crude odds ratio 1.58, 95% Cl 1.21-2.06); in 68/358 (19.0%) with recurrent thrombosis and in 206/1,774 (11.6%) with a single episode (crude odds ratio 1.78,95% Cl 1.32-2.41). Patients with combined clinical factors had a higher risk of carrying some deficiency. Biological causes of venous thrombosis can be identified in 16.93% of unselected patients. Family history of thrombosis, juvenile, spontaneous and recurrent thrombosis are the main clinical factors which enhance the risk of a deficiency. Laboratory evaluation of thrombotic patients is advisable, especially if some of these clinical factors are present.


Author(s):  
Shubham N. Dadgal ◽  
Shrikant Solanke

In modern days for structures in coastal areas it has been observed that the premature structural failures are occurs due to corrosion of the reinforcements of the designed structural member. The corrosion causes the structural damage which in turn leads to reduction in the bearing capacity of the concerned structural members. The aim of this study was to study the effect of partial replacement of fly ash to minimize the corrosion effect. Beams were designed and corroded by using artificial method known accelerated corrosion method. The beams were then tested for flexural and bond strength. Also the weight loss of the reinforced bars was been determined using electrical resistivity method. The fly ash will replace by 10% and 15%.The strength will calculate at varying percentage of corrosion at 10% and 15%. Beams will cast at M25 grade concrete. The flexural strength will test by using UTM and the bond strength will calculate using pullout test.


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