A LINEAR SHAPED CHARGE NEUTRON RADIOGRAPHY PRECISE DETECTION SCHEME
Neutron radiography was researched to detect the linear density of explosive in linear shaped charge (LSC), to determine its distribution uniformity and defective. The clear images of some samples were obtained by neutron radiography, and were processed to obtain the linear density of inner explosive. The defectives such as sparseness, discontinuity and cavity were shown clearly in the images. The method, with more intuitive and more reliable results, is more direct and simpler than existing quality testing methods for LSC, and most important, the method is a non-destructive one. This new method is of significance to the precise test of LSC and its application in precise blasting; in addition, it could be used in quality test of cord type explosive device.
Detection of Corrosion in aircraft aluminum alloys
Abstract This work shows the application of an aqueous solution of gadolinium nitrate as a contrast agent in samples of AA7075 aluminum alloy used in aircraft structures for neutron radiography (NR) detection of corrosion as the pitting and exfoliation, either hidden or not, by the same alloy. Besides this, inspection for detection of simulated corrosions of several dimensions inside a cylindrical block of aluminum alloy was carried out. The neutron radiographies were taken in the NR device of the external thermal column of the Argonaut reactor, Nuclear Engineering Institute, IEN/CNEN. An image detector was used, consisting of a gadolinium converter, 50 μm thick, and a double-coated Kodak Industrex M film.
Educating the Educators: Rethinking Subject Matter and Methods
gate? In addition to general requirements in their professional education such as psychological and social foundations and student teaching, what specifically do social studies teachers need to know and be able to do? What, in particular, do they need to study in the subject matters of the social sciences (defined here, for purposes of brevity, to include history and geography), and what should they learn about its effective direction to desired results, that is, method? Usually answers to the first question require reference to the liberal arts component of teacher education and the second to methods in the professional education component. As we shall see, this separation of subject matter and method in the education of social studies teachers, although conventional, poses problems.