ON THE INTERNAL STRUCTURE OF Cu- AND Pt-SAPPHIRE INTERFACES

La structure interne d'interfaces saphir à orientation (0001) - métal à réseau cubique faces centrées, constituées par liaison état solide non réactive, a été étudiée au microscope électronique à transmission. Il a été constaté que les métaux étaient orientés (111), parallèlement à (0001).The internal structure of (0001) oriented sapphire/fcc-metal interfaces formed in non-reactive solid-state bonding has been studied by means of transmission electron microscopy (TEM). The metals were found to be oriented (111) parallel to (0001)

Strong metal-ceramic joints

In this paper the technology for joining metals to ceramics is reviewed. The technologies of metal powder sintering, liquid phase joining with activated brazing alloys and with ceramic frit, solid-state joining, friction welding and mechanical fixation are described. In order to put some perspective on the mechanical data given in the literature, some evaluating remarks on mechanical testing are made

Strong metal-ceramic joints

In this paper the technology for joining metals to ceramics is reviewed. The technologies of metal powder sintering, liquid phase joining with activated brazing alloys and with ceramic frit, solid-state joining, friction welding and mechanical fixation are described. In order to put some perspective on the mechanical data given in the literature, some evaluating remarks on mechanical testing are made

ALUMINIUM NITRIDE CERAMIC-METAL REACTIONS

Cet article étudie les réactions entre le nitrure d'Aluminium (AlN) céramique, et les métaux et alliages appartenant au système cubique face centrée : Platine, Palladium. Palladium-Nickel e t Palladium-Argent, dans une gamme de températures comprises entre 1000 et 1500K, sous atmosphère contrôlée Azote-Hydrogène. En plus des réactions en phases solides avec le nitrure lui-même, on doit prendre en considération celles qui mettent en jeu l'oxyde Al2O3 présent à la surface de l'AlN, et thermodynamiquement plus stable que celui-ci. On constate que le comportement d'une poudre frittée à la surface de la céramique diffère de celui d'un feuillard, métallique, ce que l'on attribue à la faible mobilité de l'Azote dans AlN. Les réactions, conformément aux calculs thermodynamiques, se produisent au point triple céramique-métal-gaz entraînant la formation de composés intermétalliques et de solutions solides métalliquesReactions between AlN-ceramic and the fcc metals Pt, Pd, and Pd-Ni or Pd-Ag alloys, initiated in the solid-state between 1000 and 1500K. in a controlled H2-N2 atmosphere, are described. Apart from the reaction with AlN-ceramic, the reactions of the metals with Al2O3 are considered because the surface of AlN-ceramic consists of Al2O3 which is thermodynamically more stable than AlN. The reaction behaviour of the sintering of metal powder particles on the AlN-ceramic differs from that of solid state bonding of large area metal foils to the ceramic. This is ascribed to the low mobility of the nitrogen in the ceramic. Reactions, as predicted from thermodynamic calculations, occur a t the ceramic-metal-gas triple point where intermetallic components and metal solid-solutions form

Management of large mediastinal masses: surgical and anesthesiological considerations

Large mediastinal masses are rare, and encompass a wide variety of diseases. Regardless of the diagnosis, all large mediastinal masses may cause compression or invasion of vital structures, resulting in respiratory insufficiency or hemodynamic decompensation. Detailed preoperative preparation is a prerequisite for favorable surgical outcomes and should include preoperative multimodality imaging, with emphasis on vascular anatomy and invasive characteristics of the tumor. A multidisciplinary team should decide whether neoadjuvant therapy can be beneficial. Furthermore, the anesthesiologist has to evaluate the risk of intraoperative mediastinal mass syndrome (MMS). With adequate preoperative team planning, a safe anesthesiological and surgical strategy can be accomplished

Prenatal screening for congenital anomalies: exploring midwives' perceptions of counseling clients with religious backgrounds

Background: In the Netherlands, prenatal screening follows an opting in system and comprises two non-invasive tests: the combined test to screen for trisomy 21 at 12 weeks of gestation and the fetal anomaly scan to detect structural anomalies at 20 weeks. Midwives counsel about prenatal screening tests for congenital anomalies and they are increasingly having to counsel women from religious backgrounds beyond their experience. This study assessed midwives' perceptions and practices regarding taking client's religious backgrounds into account during counseling. As Islam is the commonest non-western religion, we were particularly interested in midwives' knowledge of whether pregnancy termination is allowed in Islam.Methods: This exploratory study is part of the DELIVER study, which evaluated primary care midwifery in the Netherlands between September 2009 and January 2011. A questionnaire was sent to all 108 midwives of the twenty practices participating in the study.Results: Of 98 respondents (response rate 92%), 68 (69%) said they took account of the client's religion. The two main reasons for not doing so were that religion was considered irrelevant in the decision-making process and that it should be up to clients to initiate such discussions. Midwives' own religious backgrounds were independent of whether they paid attention to the clients' religious backgrounds. Eighty midwives (82%) said they did not counsel Muslim women differently from other women. Although midwives with relatively many Muslim clients had more knowledge of Islamic attitudes to terminating pregnancy in general than midwives with relatively fewer Muslim clients, the specific knowledge of termination regarding trisomy 21 and other congenital anomalies was limited in both groups.Conclusion: While many midwives took client's religion into account, few knew much about Islamic beliefs on prenatal screening for congenital anomalies. Midwives identified a need for additional education. To meet the needs of the changing client population, counselors need more knowledge of religious opinions about the termination of pregnancy and the skills to approach religious issues with clients. © 2014 Gitsels-van der Wal et al