Reactive air wetting and brazing of Al2O3 ceramics using Ag–Nb2O5 filler: Performance and interfacial behavior

We firstly performed the reactive air wetting and brazing of Al2O3 ceramics using Ag–(0.5‒12)Nb2O5 fillers, where Nb2O5 can react with liquid Ag and O2 from air to generate AgNbO3. The contact angle of the Ag–Nb2O5/Al2O3 system almost linearly decreases from ~71.6° to 32.5° with the Nb2O5 content increasing, and the joint shear strength reaches the maximum of ~65.1 MPa while employing the Ag–4Nb2O5 filler, which are mainly related to the formation and distribution of the AgNbO3 phase at the interface. Moreover, the interfacial bonding and electronic properties of related interfaces were investigated by first-principles calculations. The calculated works of adhesion (Wa) of Ag(111)/Ag–O–AgNbO3(001) and AgNbO3(001)/Al2O3(100) interfaces are higher than that of the Ag(111)/Al2O3(110) interface, indicating good reliability of the Ag/AgNbO3/Al2O3 structure. The relatively large interfacial charge transfer indicates the formation of Ag–Ag, Al–O, and Ag–O bonds in the Ag/AgNbO3/Al2O3 structure, which can contribute to the interfacial bonding

Additional file 1: of Rotating shift work and menstrual characteristics in a cohort of Chinese nurses

Questionnaire. (DOC 154 kb

Challenges and successes of recruitment in the angiotensin-converting enzyme inhibition in infants with single ventricle trial of the Pediatric Heart Network.

OBJECTIVES: Identify trends of enrolment and key challenges when recruiting infants with complex cardiac diseases into a multi-centre, randomised, placebo-controlled drug trial and assess the impact of efforts to share successful strategies on enrolment of subjects. METHODS: Rates of screening, eligibility, consent, and randomisation were determined for three consecutive periods of time. Sites collectively addressed barriers to recruitment and shared successful strategies resulting in the Inventory of Best Recruiting Practices. Study teams detailed institutional practices of recruitment in post-trial surveys that were compared with strategies of enrolment initially proposed in the Inventory. RESULTS: The number of screened patients increased by 30% between the Initial Period and the Intermediate Period (p = 0.007), whereas eligibility decreased slightly by 7%. Of those eligible for entry into the study, the rate of consent increased by 42% (p = 0.025) and randomisation increased by 71% (p = 0.10). During the Final Period, after launch of a competing trial, fewer patients were screened (−14%, p = 0.06), consented (−19%, p = 0.12), and randomised (−34%, p = 0.012). Practices of recruitment in the post-trial survey closely mirrored those in the Inventory. CONCLUSIONS: Early identification and sharing of best strategies of recruitment among all recruiting sites can be effective in increasing recruitment of critically ill infants with congenital cardiac disease and possibly other populations. Strategies of recruitment should focus on those that build relationships with families and create partnerships with the medical providers who care for them. Competing studies pose challenges for enrolment in trials, but fostering trusting relationships with families can result in successful enrolment into multiple studies