Plain weave woven glass fabric reinforced epoxy (G-E) composite filled with two different types of fillers namely graphite, silicon carbide (each 5 and 10 wt%) was fabricated by hand lay-up method and compressed using...Plain weave woven glass fabric reinforced epoxy (G-E) composite filled with two different types of fillers namely graphite, silicon carbide (each 5 and 10 wt%) was fabricated by hand lay-up method and compressed using hot press. These composites were investigated for their static mechanical properties such as tensile, flexural properties and impact strength as well as mode-I fracture toughness as per ASTM standards. Experimental results on mechanical properties indicate that the strength and the modulus in tensile and flexural mode for G-E composite increase with increasing filler loading. The unfilled G-E composite has the tensile strength of 305 MPa and increased to 404.2 MPa for 10 wt% silicon carbide. However, in three-point bend mode, addition of graphite in G-E showed the highest flexural strength as well as modulus. Mode-I fracture toughness test results indicated that the graphite filler loading improved the toughness of G-E composite. Selected failed samples under tensile, bending and mode-I fracture were examined using scanning electron microscope to identify the fracture features.展开更多
Objective: This prospective cohort study was designed to assess the rule of myocardial performance (Tei) index and NT-Pro BNP serum levels in prediction of weaning failure in mechanically ventilated COPD patients. Met...Objective: This prospective cohort study was designed to assess the rule of myocardial performance (Tei) index and NT-Pro BNP serum levels in prediction of weaning failure in mechanically ventilated COPD patients. Methods: Forty patients with respiratory failure due to acute exacerbation of COPD were enrolled to this study. All patients underwent a comprehensive echocardiographic examination including tissue doppler imaging within first 12 hours of admission. NT-pro BNP serum levels were measured on admission. Patients were followed up for outcome of weaning failure. Results: Right ventricular Tei index was higher in patients with failed weaning in comparison to successfully weaned patients (mean 0.66 versus 0.36, P P = 0.007). There was no difference in serum NT-Pro BNP between successfully weaned patients and patients with weaning failure. Right ventricular Tei index showed higher accuracy in predicting weaning failure than the left ventricular Tei index (AUC 0.932 versus 0.754), while serum NT-Pro BNP showed no discrimination in predicting weaning failure (AUC 0.556). Conclusion: Tei index was superior to NT-ProBNP in prediction of weaning failure in COPD patients.展开更多
文摘Plain weave woven glass fabric reinforced epoxy (G-E) composite filled with two different types of fillers namely graphite, silicon carbide (each 5 and 10 wt%) was fabricated by hand lay-up method and compressed using hot press. These composites were investigated for their static mechanical properties such as tensile, flexural properties and impact strength as well as mode-I fracture toughness as per ASTM standards. Experimental results on mechanical properties indicate that the strength and the modulus in tensile and flexural mode for G-E composite increase with increasing filler loading. The unfilled G-E composite has the tensile strength of 305 MPa and increased to 404.2 MPa for 10 wt% silicon carbide. However, in three-point bend mode, addition of graphite in G-E showed the highest flexural strength as well as modulus. Mode-I fracture toughness test results indicated that the graphite filler loading improved the toughness of G-E composite. Selected failed samples under tensile, bending and mode-I fracture were examined using scanning electron microscope to identify the fracture features.
文摘Objective: This prospective cohort study was designed to assess the rule of myocardial performance (Tei) index and NT-Pro BNP serum levels in prediction of weaning failure in mechanically ventilated COPD patients. Methods: Forty patients with respiratory failure due to acute exacerbation of COPD were enrolled to this study. All patients underwent a comprehensive echocardiographic examination including tissue doppler imaging within first 12 hours of admission. NT-pro BNP serum levels were measured on admission. Patients were followed up for outcome of weaning failure. Results: Right ventricular Tei index was higher in patients with failed weaning in comparison to successfully weaned patients (mean 0.66 versus 0.36, P P = 0.007). There was no difference in serum NT-Pro BNP between successfully weaned patients and patients with weaning failure. Right ventricular Tei index showed higher accuracy in predicting weaning failure than the left ventricular Tei index (AUC 0.932 versus 0.754), while serum NT-Pro BNP showed no discrimination in predicting weaning failure (AUC 0.556). Conclusion: Tei index was superior to NT-ProBNP in prediction of weaning failure in COPD patients.