The father of instrumental microanalysis, Raymond Castaing, died on April 10, 1998. With him, we lost one of the outstanding figures in modern materials characterization. He was creative and innovative in physical research, in invention of instruments, in teaching, and in science management. At a time when science tends toward an inexorable division into smaller and more specialized provinces, an investigator of truly wide-ranging interests and capabilities, in the best traditions of renaissance curiosity, has left us.

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As Si(Li) detector technology has matured, many of the fundamental problems have been addressed in the competition among manufacturers and there is now an expectation, implied by many textbooks, that all energy-dispersive X-ray (EDX) detectors are made and will perform in the same way. Although there has been some convergence in Si(Li) systems and these are still the most common, manufacturing recipes still differ and there are many alternative EDX devices, such as microcalorimeters and room temperature detectors, that have both advantages and disadvantages over Si(Li). Rather than emphasizing differences in technologies, performance measures should reveal benefits relevant to the intended application. The instrument is inevitably going to be a “black box” of integrated components; this article reviews some of the methods that have been applied and introduces some new techniques that can be used to assess performance without resorting to complex software or sophisticated mathematical algorithms. Sensitivity, resolution, artefacts, and stability are discussed with particular application to compositional analysis using electron beam excitation of X-rays in the 100-eV to 10-keV energy region.

Cryogenic energy-dispersive X-ray detectors are being developed because of their superior energy resolution (10 eV FWHM for keV X-rays) compared to that achieved in semiconductor energy-dispersive spectrometry (EDS) systems. So far, their range of application is limited because of their comparably small size and low count rate. We present data on the development of superconducting tunnel junction (STJ) detector arrays to address both of these issues. A single STJ detector has a resolution of around 10 eV below 1 keV and can be operated at count rates of the order 10,000 counts/sec. We show that the simultaneous operation of several STJ detectors does not dimish their energy resolution significantly, and it increases the detector area and the maximum count rate by a factor given by the total number of independent channels.

Microscopy continues to be a rapidly evolving field. Advances in instrumentation and image processing/analysis in traditional areas of TEM, SEM, and micro-analysis have taken place in tandem with developments in force-based microscopy and light microscopic imaging systems. MSA, through its programs and publications, has been evolving as well to meet the challenges and opportunities these advances provide for investigators in both the biological and physical sciences.

The processes of melting and freezing of aluminum (Al) particles have been observed directly in a transmission electron microscope. The liquid phase nucleated preferentially at the surface of an Al particle, surrounding the crystalline solid at the onset of melting. The liquid phase then propagated inside the Al particle at the expense of the solid.

In 1995, we presented the initial design and demonstrated operation of the Tele-Presence Microscopy (TPM) Collaboratory at ANL. At that time the primary interaction mode for the Collaboratory was passive operation where the user was given a fixed interaction space with the system. Since then a number of changes have been implemented in both the system and its configuration. While the TPM Site is still accessed using browser based technology (URL = http://tpm.amc.anl.gov) the decisions which have been made at ANL since then, have necessitated that restrictions to the nature of the client browser software. Due to the requirement that TPM provide both a platform independent persistent electronic space as well as real time imaging, we have chosen to implement server push technology. This means that only those browsers which are fully compliant with Netscape Version 2.0 or greater now have full access to the TPM Site (MS Internet Explorer is not compatible with this technology).

In this issue is an article about Albert Pre-bus, one of the pioneers in electron microscopy who recently passed away. John Watson has written much more than an obituary for this man, almost a biography. This kind of article enriches our understanding of the roots of microscopy and commemorates the contributions of an individual very important to the development of microscopy. It is my hope that this will be the first of such articles about individuals who've made major contributions to technical developments or disciplines upon which our exploration and understanding of structural and/or chemical characterization rests. If you are interested in writing an a-rticle about such an historical figure please contact me or if you have a suggestion of a name of someone you think would be desirable to have profiled, please send me that suggestion as well.

Following is a list of microscopy-related meetings and courses. The editors would greatly appreciate input to this list via the electronic submission form found in the MSA World-Wide Web page at http:// www.msa.microscopy.com/. We will gladly add hypertext links to the notice on the Web and insert a listing of the meeting in the next issue of the Journal. Send comments and questions to Barbara Reine, [email protected] or Nestor Zaluzec, [email protected].

Joint meeting of the Microscopy Society of America (57th) and the Microbeam Analysis Society (33rd).

The Local Arrangment Committee (LAC) welcomes attendees to Portland and has put together several social events for the Microscopy & Microanalysis '99 meeting that we hope registrants and their families will enjoy. A list of those events and other happenings in the greater Portland area can be obtained on our web page at: http:// www.ohsu.edu/core. Briefly, for those of you arriving on Saturday and who would like the opportunity to have a taste of the region's award-winning lagers, porters, and stouts that evening, there will be a brew bus tour of several of the local pubs. On Sunday morning, for the golf enthusiast, we are sponsoring the annual golf tournament at the spectacular Skamania Lodge in the heart of the Columbia River Gorge. The course is located right off the Columbia River, in Washington, not far from Portland.

One of the primary research components of the DOE2000 Materials Microcharacterization Collaboratory involves studies of catalyst materials for reduction of NOx emissions from diesel engine exhausts. A series of experimental catalysts is currently under investigation with colleagues from Ford Research Laboratory. The major thrust of this research is the study of catalyst reactions to determine the progressive changes in the structure and morphology of the catalytic materials with temperature and time under conditions simulating diesel exhaust exposures. Because the High Temperature Materials Laboratory (HTML) provides an ex-situ reactor system that permits TEM samples to be examined after sequential reactions without intermediate atmospheric exposures, the research was undertaken on a collaboratory basis, with microscopy sessions conducted remotely via telepresence. This permits Ford scientists to interact with HTML (and/or other collaboratory) scientists during the TEM sessions, but does not require their time and involvement during the actual reactor runs. The first of these telepresence sessions was held recently, as described below.

One of the two men who first brought the electron microscope to the North American continent in 1938 died on December 16, 1997, at his home in Columbus, Ohio. This description of Dr. Albert Prebus' life is not so much an obituary as it is a recognition of a quiet, modest, unassuming scientist, whose pioneering work in electron microscopy contributed directly to the great explosion of scientific knowledge, which has been characteristic of the last half of the twentieth century.

As the new President of the Microscopical Society of Canada, I am aware that it is going to be difficult to follow in the footsteps of our past Presidents. A major concern, as with many societies, is the decline in membership; the MSC/SMC is no different.

Originally designed as position-sensitive detectors for particle tracking, silicon drift detectors (SDDs) are now used for high-count rate X-ray spectroscopy, operating close to room temperature. Their low-capacitance read-node concept places them among the fastest high-resolution detector systems. They have been used in a new spectrum of experiments in the wide field of X-ray spectroscopy: fluorescent analysis, diffrac-tometry, materials analysis, and synchrotron experiments such as X-ray holography and element imaging in scanning electron microscopes. The fact that the detector system can be used at room temperature with good spectroscopic performance and at −10°C with excellent energy resolution, avoiding liquid nitrogen for cooling and high-quality vacuum, guarantees a large variety of new applications, independent of the laboratory environment. A brief description of the device principles is followed by basics on low noise amplification. The performance results of a complete detector system are presented as well as some dedicated applications already realized, including use in a surface mapping instrument and use of a “mini-spectrometer” for the analysis of works of art. Fully depleted pn-charge-coupled devices (pn-CCDs) have been fabricated for the European X-ray Multi-Mirror mission (XMM) and the German X-ray satellite ABRIXAS, enabling high-speed, low-noise, position-resolving X-ray spectroscopy. The detector was designed and fabricated with a homogeneously sensitive area of 36 cm2. At −70°C it has a noise of 4 e- rms, with a readout time of the total focal plane array of 4 msec. The maximum count rate for single photon counting was 105 cps under flat field conditions. In the integration mode, more than 109 cps can be detected at 6 keV. Its position resolution is on the order of 100 μm. The quantum efficiency is higher than 90%, ranging from carbon K X-rays (277 eV) up to 10 keV.

In this work, the high-temperature behavior of nanocrystalline TiO2 is studied using in situ transmission electron microscopy (TEM). These nanoparticles are made using wet chemical techniques that generate the anatase phase of TiO2 with average grain sizes of 6 nm. X-ray diffraction studies of nanophase TiO2 indicate the material undergoes a solid-solid phase transformation to the stable rutile phase between 600° and 900°C. This phase transition is not observed in the TEM samples, which remain anatase up to temperatures as high as 1000°C. Above 1000°C, nanoparticles become mobile on the amorphous carbon grid and by 1300°C, all anatase diffraction is lost and larger (50 nm) single crystals of a new phase are present. This new phase is identified as TiC both from high-resolution electron microscopy after heat treatment and electron diffraction collected during in situ heating experiments. Video images of the particle motion in situ show the nanoparticles diffusing and interacting with the underlying grid material as the reaction from TiO2 to TiC proceeds.

One of the missions of the NIST Manufacturing Engineering Laboratory (MEL) is to improve and advance length metrology in aid of U.S. Industry. This responsibility is found within the Precision Engineering Division (PED). The successful development of a “Collaboratory” for TelePresence Microscopy provides an important new tool to promote technology transfer in the area of length metrology and measurement technology. NIST and Texas Instruments, under the auspices of the National Advanced Manufacturing Testbed (NAMT) and in collaboration with the University of Illinois are developing a microscopy collaboratory testbed. This facility is designed to demonstrate the value of telepresence microscopy within a large distributed manufacturing facility such as Texas Instruments and between organizations such as NIST, Texas Instruments and Universities.

Telepresence Microscopy is an application of the state-of-the-art Internet based technology to long-distance scientific endeavors.