MSA's Megabooth (Booth # 1022) provides many services for meeting attendees. The Cyber Cafe offers free internet access. While you're waiting for a terminal, you can examine copies of recent microscopy books, for both adult microscopists and children. Sample DVDs of meeting tutorials are available for review. You can post a resume or job opening, or sign up for the exhibitor tutorials. Free copies of Microscopy Today are available. You can get information on MSA membership and MSA's technologist certification and undergraduate scholarship programs. Project MICRO, MSA's precollege outreach program and the Technologists' Forum both have information desks.

Four leaf preparation techniques (air drying, tetramethylsilane air drying, critical point drying, and freeze substitution) used in scanning electron microscopy (SEM) were evaluated with respect to the degree of cellular distortion they produce in stomatal guard cells of leaves of Dactylis glomerata and Elymus canadensis. Surface morphological distortion and cuticle disruption in the air-dried and tetramethylsilane air-dried leaves, and cuticle disruption within the critical point-dried tissue made it difficult to obtain measurements.The freeze-substituted tissue experienced little cuticle disturbance, and the cellular morphology appeared normal. The length of the guard cells did not significantly differ between the air-dried, tetramethylsilane air-dried, critical point-dried, or freeze-substituted samples. Widths did significantly vary, with the freeze-substituted tissue having lower values than tissues treated with the other treatments. Freeze substitution methodology produced SEM images that appear to be less distorted and allow easy and precise measurement.

The UFeB4 phase present in different alloys of the B–Fe–U system was studied by powder X-ray diffraction (PXRD) and scanning electron microscopy complemented with energy-dispersive spectroscopy and electron backscattered diffraction (EBSD). The PXRD data showed that the ternary compound crystallized adopting essentially the YCrB4-type structure. However, microstructural observations revealed that under high undercooling conditions the UFeB4 phase exhibits a random distribution of defects parallel to, which are consistently associated with intense higher-order Laue zone rings in EBSD patterns. Indexation of the EBSD patterns showed that the defective structure is compatible with an intergrowth of YCrB4- and ThMoB4-type layers according to the (010)YCrB4//(110)ThMoB4 and [001]YCrB4//[001]ThMoB4 orientation relation previously reported for an analogous compound. Magnetic studies indicated that the annealed UFeB4 compound has a paramagnetic behavior in the 2–300 K temperature range.

Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

Aluminum nitride (AIN) with high thermal conductivity has been considered as a potential substrate material for microelectronics. However, the thermal conductivity of polycrystalline AIN ceramics, prepared by liquid-phase sintering, is significantly lower than that of AIN single crystal. It has been shown that the thermal conductivity of AIN is inversely proportional to the oxygen content dissolved in the AIN lattice. Furthermore, the microstructure of AIN can also influence the thermal conductivity considerably. In the present study, we investigated the effect of grain boundaries and secondary phase distributions on thermal conductivity of two selected high density samples which contained similar oxygen content but showed different thermal conductivities.

Experimental details and selected properties of Samples A and B are shown in Table 1. Sample A with 0.8 wt% Y2O3 additive was embedded in an AIN powder bed in a BN crucible covered by a BN lid (not gas tight) during sintering, while Sample B with 3.9 wt% Y2O3 was embedded in an AIN powder bed in an open graphite crucible.

Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007

Development of high-density longitudinal magnetic recording media (used for computer hard disks) with good noise performance and high thermal stability requires optimization of both alloy composition and processing methods. In CoCr(PtTa) thin films, intergranular Cr segregation is responsible for decoupling the magnetic exchange between the small ferromagnetic grains. The corresponding Cr depletion within the grains affects the “bulk” magnetic anisotropy. However, the nanoscale structural and chemical details that are needed for modeling and for guiding material development are not well understood. Energy-filtered transmission electron microscopy (EFTEM) has been used to characterize a series of CoCrTa/Cr, CoCrPt/Cr, and CoCrPtTa/Cr media sputtered under various processing conditions, in order to understand their structure-property-processing relationships.

Processing typical for hard-disk media was used: 30 or 60-nm films of a Cr underlayer followed by a Co alloy were d.c. magnetron sputtered onto a NiP-plated Al substrate pre-heated to 250°C.

Accurate descriptions of dispersed metals are of central importance in optimizing the activity, selec-tivity and stability of a diverse set of catalysts and chemistries. Improved methods for quantifying metal dispersion, alloying and support interactions help form mechanistic understandings of catalyst function at the atomic scale. In this paper we discuss ideal capabilities of a transmission electron microscope for catalysis, and give an update on the use of a next-generation field-emission TEM/STEM for structural and analytical studies of supported metal catalysts.

Characterizing nanometer-sized metal particles requires high performance imaging, high sensitivity analysis, and minimal disruption of the physical state of the particles. No single microscope combines all key performance factors with ease of use. Schottky field-emitter instruments provide high current-density probes with excellent stage stability (nm drifts in > 10 min. observed), < 0.7 eV energy reso-lution for EELS, and a turbo-pumped vacuum system for minimal carbon contamination while using nanometer probes and nanoamps of current. Scanning TEM performance is also key.

Two-phase α2+γ TiAl alloys with microalloying additions, Fig. 1, are of interest due to the high strength-to-weight ratio they can provide in automotive and aircraft applications. In boron-doped α2+γTiAl containing Cr, Nb, and W, the B levels were found to be significantly depleted below the nominal alloy content in both the α2 andγ phases. The boron solubilities in the γ and α2 phases were 0.011 ± 0.005 at. % B and 0.003 ± 0.005 at. % B, respectively in Ti-47% Al-2% Cr-1.8% Nb-0.2% W-0.15 % B that was aged for 2 h at 900°C (base alloy). The majority of the B was in a variety of borides including TiB, TiB2 and a Cr-enriched (Ti,Cr)2B precipitate. With the exception of the smaller (< 50 nm thick) Cr-enriched (Ti,Cr)2B precipitates, Fig. 2, most of the borides were larger than ∼100 nm. A significant proportion of the microalloying additions is in these borides, Table 1.

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 JoAn Hudson, [email protected] or Nestor Zaluzec, [email protected].

Millipedes are ecologically important soil organisms and may also be an economically threatening species in rural and urban areas when population outbreaks occur. In order to control infestations commercial formulations of deltamethrin have been commonly applied, even though there are few studies about the effects of such insecticide on millipedes. This paper describes the effects of this insecticide on millipedes showing neurotoxic effects assessed by synapsin labeling and confocal microscopy. Deltamethrin concentrations related to the DL50 of the active ingredient and a field concentration were applied topically in the diplopod Gymnostreptus olivaceus to evaluate the behavior, mortality rate, and synapsin levels in the brain 12, 24, and 48h after contact with deltamethin. The insecticide caused mortality at the higher concentrations employed, in which no change was observed in neurotransmission in the survivors. In contrast, at field concentrations, deltamethrin did not cause any deaths, but triggered significant changes in synapsin levels. The results obtained form the synapsin labeling provide several interpretations suggesting that the isolated application of this tool must be associated with additional tools in order to evaluate biologically induced effects of deltamethrin in an accurate way. In addition, the feasibility of chemical control of millipedes with deltamethrin is questioned.

Individual flux lines in superconducting specimens have been recently observed using a 300kV holography electron microscope equipped with a cold field emission gun in the transmission mode by means of the out-of-focus method. In this way it has been possible to observe the dynamic behaviour of fluxons depending upon the variations of the temperature and/or the applied magnetic field or current. The main disadvantage of this method is that correlation with structural defects is troublesome owing to the large defocus distance (of the order of 1 cm for conventional superconductors) necessary for the detection of flux lines.

This drawback is not present in the Foucault technique, where the contrast is generated in the focused image by masking part of the transmitted beam by means of an aperture. Therefore, some preliminary calculations have been made recently using one-dimensional models, which allow for a quick and easy simulation of the factors affecting the experimental conditions .

This study provides a quantitative validation of qualitative automated three-dimensional (3-D) analysis methods reported earlier. It demonstrates the applicability and quantitative accuracy of our method to detect, characterize, and count Feulgen stained cell nuclei in two tissues (hippocampus and testes). A laser-scanned confocal light microscope was used to record 3-D images i which our algorithms automatically identified individual nuclei from the optical sections given an estimate of minimum nuclear size. The hippocampal data sets were also manually counted independently by five trained observers using the STERECON 3-D image reconstruction system. The automated and manual counts were compared. A nucleus-by-nucleus comparison of the manual and automated counts verified that the automated analysis was accurate and reproducible, and permitted additional quantitative analyses not available from manual methods. The algorithms also identified subpopulations of nuclei within the hippocampal samples, and haploid and diploid nuclei in the testes. Our methods were shown to be repeatable, accurate, and more consistent than manual counting.

We report here a specific type of edge strength anisotropy observed in field emission scanning electron microscope (FESEM) images. The images show weaker edge gradients in the scanning direction and hence these edges frequently go undetected. Direct application of edge detection algorithms to images with nondistinct edges, such as powder particles, show strong bias to edges perpendicular to the scanning direction. Edge orientation polarograms obtained from these images always show strong fictitious particle orientation in the scanning direction. In this work, we discuss an edge-sharpening algorithm that corrects for this bias and results in relatively more accurate and consistent edge orientation information.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.