Tantalum radiography of the respiratory tract in dogs.
ALTHOUGH radiography of the respiratory tract was suggested by Chevalier Jackson in 1918 1 the full potential of this diagnostic aid has never been realized. The major drawbacks of the three radiopaque materials thus far employed in radiography of the airway 1-4 have been that:
DISPLACEMENT IRRIGATION OF NASAL SINUSES: A NEW PROCEDURE IN DIAGNOSIS AND CONSERVATIVE TREATMENT
The procedure here presented is a simple method of introducing fluids into the sphenoid and posterior ethmoid sinuses. Heretofore, the irrigation of these sinuses has been rendered difficult by their positions and the inaccessibility of their ostia. Only occasionally can the normal opening of the sphenoid be used for the introduction of a cannula, while in the case of the posterior ethmoid cells it is practically impossible. Perforating the sinus walls, for the purpose of instilling fluids, is dangerous; it is not always accurate, and it produces inflammatory reactions which defeat the essential purpose of the treatment. It occurred to me that those very mechanical obstacles which prevent the proper drainage of the posterior cells might be turned to account in similarly retaining therapeutic solutions in contact with the lining membrane. My problem, therefore, was the introduction of such solutions into the sinuses without producing trauma, and the
Failure analysis for poor solderability of Au surface of PCB
Nonwetting is one of the common problems and is always rejected in electronic assemblies. ENIG pads of a PCBA exhibited nonwetting after lead-free reflow soldering. With the aid of stereomicroscope, SEM&EDS and XRF, a series of analysis was performed. And after visual inspection, surface and cross section analysis, thickness measurement and solderability test, it can be inferred that oxidation of plating surface was the main reason for nonwetting, and corrosion in Ni plating caused an adverse impact on solderalibity.