We have observed that a slight crystal tilt away from the zone axis paradoxically decreases the dynamical extinction length, as if the electron-crystal interaction increases. This effect disappears at larger tilt angles. Using the simplified channeling theory, this behavior is explained.

This study describes the use of transmission electron holography to determine the mean inner potential of polystyrene. Spherical nanoparticles of amorphous polystyrene are studied so that the effect of specimen thickness on the phase shift of an incident electron wave can be separated from the intrinsic refractive properties of the specimen. A recursive four-parameter χ-squared minimization routine is developed to determine the sphere center, radius, and mean inner potential (Φ0) at each pixel in the phase image. Because of the large number of pixels involved, the statistics associated with determining a single Φ0 value characteristic of a given sphere are quite good. Simulated holograms show that the holographic reconstruction procedure and the χ-squared analysis method are robust. Averaging the Φ0 data derived from ten phase images from ten different polystyrene spheres gives a value of Φ0PS = 8.5 V (σ) = 0.7 V). Specimen charging and electron-beam damage, if present, affect the measurement at a level below the current precision of the experiment.

Three-dimensional image formation in an interference confocal scanning microscope under ultra-short pulsed beam illumination is investigated in this study. The novelty of this new image system is that it keeps advantages in femtosecond interferometry but also provides a femtosecond-resolved three-dimensional image without necessarily using an ultrafast detector. For a 5-fs pulsed beam illumination, spatial resolution in the axial and transverse directions in this system is improved by approximately 45% and 15%, respectively, compared with that in the case of continuous wave illumination. However, strong chromatic aberration caused by an ultrashort pulsed beam can result in a degradation of spatial and temporal resolution, whereas weak chromatic aberration may lead to an improvement in transverse resolution.

This study discusses the use of in situ high-resolution transmission electron microscropy (HRTEM) techniques to determine the structure, composition, and interphase boundary dynamics during phase transformations at the atomic level. Three main in situ HRTEM techniques are described: (1) in situ HRTEM dynamic studies that are performed on the same precipitate plates from different viewing directions to determine the three-dimensional structure of the interfaces; (2) in situ compositional mapping of precipitate interfaces obtained by energy-filtering TEM experiments at temperature in a HRTEM, and (3) real-time HRTEM image simulations that are being created for comparison with and interpretation of experimental in situ HRTEM dynamic observations. The results from these studies demonstrate that it is possible to understand the mechanisms and kinetics of interphase boundary motion at the atomic level.

Electron beam X-ray microanalysis with semiconductor energy-dispersive spectrometry (EDS) performed with standards and calculated matrix corrections can yield quantitative results with a distribution such that 95% of analyses fall within ±5% relative for major and minor constituents. Standardless methods substitute calculations for the standard intensities, based either on physical models of X-ray generation and propagation (first principles) or on mathematical fits to remotely measured standards (fitted standards). Error distributions have been measured for three different standardless analysis procedures with a suite of microanalysis standards including metal alloys, glasses, minerals, ceramics, and stoichiometric compounds. For the first-principles standardless procedure, the error distribution placed 95% of analyses within ±50% relative, whereas for two commercial fitted standards procedures, the error distributions placed 95% of analyses within ±25% relative. The implication of these error distributions for the accuracy of analytical results is considered, and recommendations for the use of standardless analysis are given.

Our original “Telemicroscopy” project has now been expanded into a project in which we aim to provide a “Collaboratory for Microscopic Digital Anatomy” (CMDA) Tools being developed will provide a researcher at a remote site distributed interaction with unique instrumentation for data acquisition, as well as significantly enhanced capabilities to derive and analyze 3D data by accessing high performance computers. Initial focus is on the collection and analysis of data from a unique IVEM located at the National Center for Microscopy and Imaging Research (NCMIR). The NCMIR instrument is one of a few IVEMs in the USA made available to the biological research community by the National Center for Research Resources of the National Institutes of Health. This particular instrument was specially designed to obtain images from thick specimens containing substantial 3D structure. Because of the characteristics of the EM, images acquired represent two dimensional projections of the 3D structure within the specimen.

In many cases in experimental science, the instrument interface becomes a limiting factor in the efficacy of carrying out unusual experiments or prevents the complete understanding of the acquired data. We have developed an advanced interface for scanning probe microscopy (SPM) that allows intuitive rendering of data sets and natural instrument control, all in real time. The interface, called the nanoManipulator, combines a high-performance graphics engine for real-time data rendering with a haptic interface that places the human operator directly into the feedback loop that controls surface manipulations. Using a hand-held stylus, the operator moves the stylus laterally, directing the movement of the SPM tip across the sample. The haptic interface enables the user to “feel” the surface by forcing the stylus to move up and down in response to the surface topography. In this way the user understands the immediate location of the tip on the sample and can quickly and precisely maneuver nanometer-scale objects. We have applied this interface to studies of the mechanical properties of nanotubes and to substrate-nanotube interactions. The mechanical properties of carbon nanotubes have been demonstrated to be extraordinary. They have an elastic modulus rivaling that of the stiffest material known, diamond, while maintaining a remarkable resistance to fracture. We have used atomic-force microscopy (AFM) to manipulate the nanotubes through a series of configuration that reveal buckling behavior and high-strain resilience. Nanotubes also serve as test objects for nanometer-scale contact mechanics. We have found that nanotubes will roll under certain conditions. This has been determined through changes in the images and through the acquisition of lateral force during manipulation. The lateral force data show periodic stick-slip behavior with a periodicity matching the perimeter of the nanotube.

We describe here a simple and inexpensive solution for marking film negatives with identification numbers before film development. This technique avoids the purchase of expensive camera-magazines with data-backs, and it reduces the risk of misidentifying film negatives.

X-ray counting statistics plays a key role in establishing confidence limits in composition determination by X-ray microanalysis. The process starts with measurements of intensity on one or more samples and standards as well as related background determinations. Since each individual measurement is subject to variability associated with counting statistics, it is necessary to combine all of the counting variability according to established mathematical procedures. The next step is to apply propagation of error calculations to equations for quantitative analysis and determine confidence limits in reported composition. Similar concepts can also be applied to trace element determination. This approach can then be combined with spectral simulation modeling, making it possible to predict detectability limits without additional measurements.

Electron microscopy recently lost one of its outstanding pioneers when John Reisner passed away on June 18 of this year. We who have known and respected John, pause here to remind ourselves of his many contributions to our field and to visualize for later generations the times and social forces that brought forth such a remarkable human being. He was remarkable because of his courageous and skillful management of problems arising from a severe case of poliomyelitis. He was remarkable because of his family's determination to help him reach his full potential. He did in fact lead American development of the electron microscope at RCA from 1950 to 1970 and served (E)MSA in several roles from 1950 on until very near the end of his life, including as President of the Society.

We discuss various techniques for the characterization of supported nanoparticles by in situ plan-view transmission electron microscopy. In particular, we discuss here mechanisms of image contrast formation by particles undergoing reorientation on the surface of a single crystal substrate. We consider reorientation by a variety of mechanisms including rotation, sintering and grain growth, and surface diffusion. Experimental observations are presented and the data compared with theoretical predictions.

X-ray Diffraction: A Practical Approach, C. Suryanarayana and M. Grant Norton, 1998. Plenum Press, New York and London. xiii + 273 pages. (hardback, $49.50, U.S. and Canada; $59.40, elsewhere).

It is the aim of this text to teach undergraduates majoring in materials science the use of powder X-ray diffraction for materials characterization. Since it does not treat X-ray diffraction and crystallography in a general way, it would have been better if it were given a more specific title, such as X-Ray Powder Diffraction for Metallurgical Characterization. A Primer and Workbook. As a laboratory course with work pages to be filled out by the student, it might have been spiral-bound to facilitate such use.

The use of Pt to mark the initial location of heterophase boundaries in solid-state reactions was extended to investigate the motion of interfaces during a thin-film solid-state reaction between In2O3 and MgO in the presence of an electric field. The Pt markers were prepared by sputtering a thin Pt film onto a single-crystal substrate. The resulting multilayer was then heated prior to thin-film deposition to de-wet the Pt film and thus form an array of small, isolated particles. These particles serve as fine-scale markers for tracking the motion of interfaces. However, there are certain situations in which the markers can move with the interface.

Recently there has been great interest in creating Internet and Intranet tools for electron microscopy. We can somewhat arbitrarily divide the goals of these tools into three categories: (1) Service lab interaction, (2) Laboratory extension, (3) Teaching & outreach. The service lab wants to disseminate the results of experiments quickly to its customers. Sometimes it needs to do this during the experiments for verification that the experiments are being correctly performed, but most collaboration problems can be solved with a phone discussion while looking at the same image. This level of interactivity is not sufficient for the laboratory extension community that wants real time experimental results and perhaps even controls of the equipment projected to a remote location. Finally, several groups have expressed interest in bringing observation and control of instrumentation into the classroom to potentially many computers and potentially many different displays of the experiment in progress.

It is with much pleasure and gratification that I encourage you to read the messages from the presidents of the five societies for whom Microscopy and Microanalysis is the official journal. Each of the five presidents graciously agreed to write a message for this first issue of 1998. Writing such messages is often a burden on an already overtaxed schedule and we very much appreciate the effort they all have made. These contributions reflect one of the primary goals of the News and Commentary, that is, to be an arena for contributions from all of the societies affiliated with the journal—contributions of interest to a broad spectrum of microscopists. We hope to truly make this journal an endeavor reflecting international exchange and cooperation. Again, I thank these presidents for taking the time to write these words. So please, respect this effort and take the time to read their comments. The five presidential messages are presented in the order of their listing on the front cover of the journal, which reflects the order in which the particular society became affiliated with Microscopy and Microanalysis.

Fluorescence Microscopy and Fluorescence Probes, edited by Jan Slavik, 1996. Plenum Press, New York and London. 306 pages. (hardback, $95)

This volume is a compilation of abstracts of papers presented at the Fluorescence Microscopy and Fluorescence Probes Conference held in Prague in June 1995. This conference was one of the first tangible results of the end of the Cold War in the field of microscopy. As such, it attracted a great many of those who constitute the vanguard of progress in the field of fluorescence microscopy, on both sides of the old East-West divide. About one-third of the 127 contributors were from the West.

We describe here real-time, in situ observations of the formation of nanosize germanium (Ge) islands on silicon (Si). The deposition of Ge onto electron-transparent Si(100) takes place in a UHV transmission electron microscope that has been modified to allow chemical vapor deposition to be carried out in the polepiece. We recorded the growth process at video rate and were therefore able to follow the evolution of individual islands. As the islands grew, we observed a coarsening process similar to classical Ostwald ripening, but which leads at certain times to a bimodal distribution of island sizes. We show that this phenomenon can be understood using a model in which a conventional coarsening process is modified by a transition between two different island shapes.

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.