Charles S. Barrett - Böcker

The 37th Annual Denver Conference on Applications of X-Ray Analysis was held August 1-5, 1988, at the Sheraton Steamboat Resort and Conference Center, Steamboat Springs, Colorado. As usual, alternating with x-ray diffraction, the emphasis this year was x-ray fluorescence, but as has been the pattern for several occasions over the last few years, the Plenary Session did not deal with that subject, specifically. In an attempt to introduce the audience to one of the new developments in x-ray analysis, the title of the session was "High Brilliance Sources/Applications," and dealt exclusively with synchrotron radiation, a topic which has made a very large impact on the x-ray community over the last decade. As the organizer and co-chairman of the Plenary Session (with Paul Predecki), it is my responsibility to report on that session here. The Conference had the privilege of obtaining the services of some of the preeminent practitioners of research using this remarkable x-ray source; they presented the audience with unusually lucid descriptions of the work which has been accomplished in the development and application of the continuous, high intensity, tunable, polarized and collimated x-rays available from no facility other than these specialized storage rings. The opening lecture (and I use that term intentionally) was an enthusiastic description of "What is Synchrotron Radiation?" by Professor Boris Batterman of Cornell University and the Cornell High Energy Synchrotron Sourc(! (CHESS).

The continuing success of the Denver X-Ray Conference is, it seems to me, the consequence of three equally important facets of each meeting. These are: 1) the collegial atmosphere and workshops at which experts and novices mix, talk, and informally share information at many levels; 2) the plenary session at which information is presented that intentionally brings new ideas to attendees to broaden the scope of the field; and 3) the traditional sessions in which interesting reports on current research and applications are presented in a timely and professional way. The first and last of these are discussed separately by Paul Predecki and are organized (no small task!) by the entire advisory board. This requires much more than deciding whether yet another workshop on specimen preparation is needed and whom to prevail upon to organize and present it. In fact, few attendees at these workshops ever appreciate the level of effort that Paul and his staff expend to make sure everything comes off smoothly, even when hundreds of copies of handouts need to be whipped off at the last moment, travel problems arise, or unusual audio­ visual aids are suddenly needed. But my topic here is the second of the three facets listed above - the plenary session. Organizing this falls to a single individual, on the theory that one person can then approach enough others as speakers to put together a unified and yet diverse program of related and interesting review papers.

The 35th Annual Denver Conference on Applications of X-Ray Analysis was held August 4-8, 1986, on the campus of the University of Denver. Since the previous year's conference had emphasized x-ray diffraction, this year the Plenary Session spotlighted x-ray fluorescence, with the title "Trends in XRF: A World Perspective," featuring renowned speakers from three major areas. XRF IN NORTH AMERICA, by Prof. D. E. Leydon, from Colorado State University, dealt specifically with developments in the fields of instrumentation, data treatment and applications in that part of the world. Prof. H. Ebel, from the Technical University of Vienna, discussed XRF IN EUROPE, concentrating on subjects including total reflection, improved fundamental parameters, quantitation without standards and imaging techniques. Tomoya Arai, of the Rigaku Industrial Corporation in Japan, in considering XRF IN THE FAR EAST, described the scientific activity in XRF and the applications thereof, primarily in Japan and China. These plenary lectures were interspersed with short discussions of PERSONAL OBSERVATIONS on the subject by the co-chairmen of the SeSSion, Ron Jenkins and myself. The intent of this session was to bring the audience up-to-date on the status of the field in various parts of the world, and to give some feeling concerning where it is likely to go in the immediate future. Hopefully, the publication of the written versions of those presentations in this volume will make the authors' thoughts available to many who could not be present at the conference.

The 33rd Annual Denver Conference on Applications of X-Ray Analysis was held July 30-August 3. 1984. on the campus of the University of Denver. Following the recent tradition of alternating plenary lecture topics between X-ray diffraction and X-ray fluorescence at the confer­ ence. the plenary sessions dealt with topics of X-ray fluorescence. Prof. H. Aiginger presented a plenary lect~re on TOTAL REFLECTANCE X-RAY SPECTROMETRY which admirably described this relatively new technique. J. C. Russ discussed XRF AND OTHER SURFACE ANALYTICAL TECHNIQUES which gave an excellent overview of the role XRF plays in a modern analytical laboratory. J. E. Taggart. Jr. described THE ROLE OF XRF IN A MODERN GEOCHEMICAL LABORATORY and presented many case histories of the configura­ tion of analytical equipment in several geochemical laboratories. The plenary lectures demonstrated both the dynamic nature of research in X-ray fluorescence. and the important role X-ray spectrom­ etry plays in the arsenal of analytical methods found in modern labora­ tories. Total reflectance X-ray spectrometry takes advantage of con­ sideration of the geometry of the X-ray optics. Potentially. new sample types may be considered as X-ray fluorescence specimens using this technique.

The 38th Annual Denver Conference on Applications of X-Ray Analysis was held July 31 - August 4, 1989, at the Sheraton Denver Technical Center, Denver, Colorado. The conference alternates emphasis between x-ray diffraction and x-ray fluorescence, and this being an odd year the emphasis was on diffraction. Thus the Plenary Session was slanted toward diffraction in general and thin film analysis in particular. The Plenary Session on x-ray analysis of thin films did not just happen this year but really began four years ago with Paul Predecki suggesting a special session devoted to thin film techniques. The session generated a great deal of interest, so Paul suggested that a workshop on thin films should be slated for the 1987 conference. A full day was devoted to the workshop, which was split into a half day on epitaxial thin films and the other half day on polycrystalline thin films. The workshop attendance indicated a great deal of interest in this topic, leading to this year's Plenary Session. The first two speakers of the Plenary Session (B. Tanner and K. Bowen) have been key throughout the thin film activities. They were invited speakers for the 1985 special session on thin films and instructors for the 1987 workshop on epitaxial thin films.

The University of Denver and its staff members deserve much credit for organizing and operating this Denver X-ray Conference year after year, for there seems to be no doubt that it and the yolumes that result from it are filling a need. The interests covered by the papers at one of these conferences vary from year to year and as a whole cover a wide spread of topics. This is as it should be. Old problems that have been with us for many years are being attacked again with new and more effective tools, new problems are continually arising, and new methods of great power are being developed. These developments are occurring in each of the fields covered, as may readily be seen by a glance at this twelfth volume and other recent volumes of this series. It seems clear that the policy of having these conferences and these volumes cover a wide field rather than a single one such as, for example, structure determination, or fluorescence analysis, is a policy that meets with general approval and should be continued. I understand there is every intention to do so. C. S. Barrett It is customary to acknowledge in each volume the invited session chairmen of the three-day meeting. They and the sessions at which they presided (21-23 August 1968) were as follows: CRYSTALLOGRAPHY AND DIFFRACTION. C. S. Barrett, University of Chicago, Chicago, Illinois. METHODS AND THEIR APPLICATIONS. B. C. Giessen, Massachusetts Institute of Technology, Cambridge, Massachusetts.