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We report the synthesis of carbon nanowires (CNWs) via chemical vapor deposition using catalytic decomposition of ethanol on nanosized transition metals such as Co, Fe, and Ni. Dip-coating process was used for the formation of catalytic nanoparticles, inducing the growth of CNWs on the surface of the carbon fiber paper (CFP). The liquid ethanol used as carbon source was atomized by an ultrasonic atomizer and subsequently flowed into the reactor that was heated up to a synthesis temperature of 600–700°C. Microscopic images show that CNWs of

The ability to see, or visualize, a phenomenon is an essential tool of modern biological research. Our ability to create static and dynamic images has grown exponentially in the 25 or so years since confocal microscopy became readily available. The ingenious and energetic application of insights from optical physics to biological imaging in recent years has brought us far-reaching extensions of simple imaging, including nonlinear (or multiphoton) excitation, total internal reflection imaging, and even single molecule counting techniques. The annual Omaha Imaging Symposium has since 2003 brought together experts in advanced biological imaging techniques for a one-day exposition of how these techniques help move biological science forward. The seventh iteration of the series was held Friday, April 8, 2011, at the Harper Student Life Center of Creighton University, in Omaha, Nebraska. This special section of Microscopy and Micronanalysis consists of papers from speakers at the symposium.

Since 2003, the annual Omaha Imaging Symposium has brought together experts in advanced biological imaging techniques for a one-day exposition of how advanced research imaging techniques foster progress in biological research. The eighth symposium in the series was held Friday, April 20, 2012, at the Harper Student Life Center of Creighton University, Omaha, Nebraska. This special section of Microscopy and Microanalysis consists of articles contributed by speakers at the symposium.

One of the most interesting aspects of this book is the frequency at which the contributing authors are found in the references at the end of not one, but usually several chapters: this is by no means a mistake. Editors Hacker and Gu have assembled a wealth of expertise from well-known individuals in the fields of autometallography, immunogold-silver staining and molecular morphology. Composed of 16 chapters with a total of 32 contributing authors, the material is presented in a very well organized and coherent format.

This issue of Microscopy and Microanalysis presents nine of the articles from the 9th Workshop of the European Microbeam Analysis Society (EMAS) on “Modern Developments and Applications in Microbeam Analysis” held in conjunction with the 3rd Meeting of the International Union of Microbeam Analysis Societies (IUMAS) in Florence, Italy, on May 22–26, 2005.

The peroxyformic process is based on the action of a carboxylic acid (mainly formic acid) and the corresponding peroxyacid. The influences of processing time (60–180 min), formic acid concentration (80–95%), temperature (60–80°C), and hydrogen peroxide concentration (2–4%) on peroxyformic pulping of agave leaves were studied by surface response methodology using a face-centered factorial design. Empirical models were obtained for the prediction of yield,κnumber (KN) and pulp viscosity as functions of the aforementioned variables. Mathematical optimization enabled us to select a set of operational variables that produced the best fractionation of the material with the following results: pulp yield (26.9%), KN (3.6), and pulp viscosity (777 mL/g). Furthermore, this work allowed the description and evaluation of changes to the agave fibers during the fractionation process using different microscopic and spectroscopic techniques, and provided a comprehensive and qualitative view of the phenomena occurring in the delignification of agave fibers. The use of confocal and scanning electron microscopy provided a detailed understanding of the microstructural changes to the lignin and cellulose in the fibers throughout the process, whereas Raman spectroscopy and X-ray diffraction analysis indicated that cellulose in the pulp after treatment was mainly of type I.

The present communication reports toxic effects of bleached sulfite pulp mill effluents in fish (Heteropneustes fossilis) gills, with optical, scanning electron, and transmission electron microscopy. The general adverse effects include dilation of the primary lamellar wall, curling of secondary lamellar terminals, displacement of epithelial cell layers, degeneration of secondary lamella, deposition of mucous, and severe congestion in the gill arch. The significant shortening of secondary lamellae, widening of lamellar tips, and significant decrease in the number of mitochondria in chloride cells as compared to controls are some specific effects of bleached sulfite pulp mill effluents. Scanning electron microscopy demonstrated tearing of tissues in gill lamellae and arches. Transmission electron microscopy revealed membrane distortion of mitochondria in chloride cells, loss of uniformity of microvilli in pavement cells, and abnormalities in nuclear shape in different cells of effluent-exposed fish gills. Toxicity of the bleached sulfite pulp mill effluents and its impact on fish are discussed in the light of existing literature. Further, the importance of microscopy in toxicological evaluation of environmental pollutants is emphasized in view of its specific application potential.

This study’s droplet method used a pipet tip box covered with Parafilm that was slightly dimpled to provide a depression to hold stain droplets. Grids were placed section-side down on droplets of 2% aqueous Uranyl Acetate (UA), for 10 minutes, picked up with forceps, and rinsed with a water stream from a transfer pipette. They were then placed on droplets of Reynolds Lead Citrate (LC) for 10 minutes and covered. The grids were then rinsed with .002 Normal NaOH, followed by a water stream rinse, blotted with filter paper, and stored until TEM examination. Two problems that come up using this method at times is damage to the sections as you pick up grid between staining and rinsing and having to add more rinses to the sections. With the mPrep/g method, 1 or 2 grids are placed directly into mPrep/g capsules at the microtome, into tapered grid slots that securely hold them even if a capsule is dropped. For staining, the capsules attach like pipette tips to lab pipettors. This study used a 200 μl 8-channel Gilson Pipetman to enable staining of 16 grids in 8 mPrep/g capsules. Grids were stained from reagents held in a 96-well plate (Fig 1). The first row of the 96-well plate held 40 μl of UA, the next 3 rows held 400 μl of water, then 40 μl of LC, then 3 more water rows with 400 μl of water. 8 mPrep/g capsules holding 2 grids each were attached to the 8-channel Pipetman, and dipped into the bottom of the UA reagent row. 35 μl of UA was then drawn into the capsules and held for 10 minutes. The UA was then expelled back into this row, and the capsules/pipette were moved to the first water row. In this row, 40 μl of water was rapidly drawn up and down 30 times (taking about 60 seconds) to rinse and agitate, and then repeated in the next two water rows. Then LC stain was drawn in and held for 10 minutes, followed by expelling and another 2x15 water rinses. The capsules were then rested on filter paper to drain off water, and removed and stored in the capsule storage box (which they came in) until TEM imaging.

This work comprises the structural characterization of Eucalyptus and Pinus radiata pulp fibers and their corresponding fibrillated materials, based on quantitative electron microscopy techniques. Compared to hardwood fibers, the softwood fibers have a relatively open structure of the fiber wall outer layers. The fibrillation of the fibers was performed mechanically and chemi-mechanically. In the chemi-mechanical process, the pulp fibers were subjected to a TEMPO-mediated oxidation to facilitate the homogenization. Films were made of the fibrillated materials to evaluate some structural properties. The thicknesses and roughnesses of the films were evaluated with standardized methods and with scanning electron microscopy (SEM), in backscattered electron imaging mode. Field-emission SEM (FE-SEM) and transmission electron microscopy (TEM) were performed to quantify the nanofibril morphology. In this study, we give additional and significant evidences about the suitability of electron microscopy techniques for quantification of nanofibril structures. In addition, we conclude that standard methods are not suitable for estimating the thickness of films having relatively rough surfaces. The results revealed significant differences with respect to the morphology of the fibrillated material. The differences are due to the starting raw material and to the procedure applied for the fibrillation.

Cryo-Electron Microscopy (cryo-EM) was started in the 1960-70’s and perfected in the early 1980’s [1]. It is a method in which 2-5 uL of a biological sample is placed on a grid with a holey carbon film and blotted with filter paper, then quickly plunged into liquid ethane. The buffer is frozen into amorphous ice, and the biological sample can be visualized using TEM while keeping the grid at cryogenic temperatures. A 50-100 nm layer of ice is ideal for studying proteins and 2-D crystals. For the most part, obtaining a layer of ice this thin has been controlled by the use of filter paper and the manipulations of the experimenter. For a novice this process is irreproducible and frustrating. The increasing interest and number of facilities that collect cryo-EM data is pushing the need for semi-automated sample preparation techniques that yield reproducible results.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

The airways are lined with a thin film consisting of two layers. A watery layer, the airway surface liquid (ASL) surrounds the cilia and its major function is to serve as a medium for ciliary boating of mucus out of the respiratory system. The other layer is a viscous mucus layer consisting mainly of airway cellular secretions and cellular debris.The composition and effects of altered concentrations of the constitutive elements in the ASL and mucus layer remain a mystery. in human patients, attempts have been made to determine the composition of these layers by sampling with a filter paper by touching it to the mucosa and wetting it by capillary action. This material was then removed from the filter paper and quantitative analyses using energy dispersive x-ray spectrometry (EDS) and a Hall’s thin film correction routine performed on the residue. Although differences were detected between normal and pathological material, these results did not reflect the composition of the individual layers but an average of both.Attempts have been made to determine the elemental composition of these layers in intact and in cultured rabbit trachea, bovine trachea and hamster trachea.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

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

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

Graphene appears to be a material with many potential applications. A robust and convenient method is therefore needed to evaluate the quality of graphene films. Raman spectroscopy is often used and is fast and inexpensive; however, the information content in the Raman spectrum is limited. We demonstrate an electron diffraction based method that can be routinely used to evaluate the quality of graphene thin films., Proceedings of Microscopy and Microanalysis 2014, Aug. 3-7, 2014, Hartford, Connecticut

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

A major problem now hampering increased recycling of old cardboard containers (OCC), is the presence of significant amounts of polymeric materials such as adhesives, tapes, labels and wax which enter the pulp process stream along with the cardboard and paper that was collected for recycling. Many of these materials contain very fine particles of inorganic fillers and pigments. These various contaminant constituents combine in some, as yet unknown, manner to form an extremely gummy material that deposits on paper machine surfaces and sticks tenaciously (hence the term “Stickies”). The sticky blobs are very difficult to remove and increases machine downtime and maintenance costs as well as causing blemishes on the finished container board product Light optical image analysis, UV fluorescence, FTIR and electron microscopy are being used in consort with particle size measuring instruments, TGS and DSC thermal analysis techniques, FTIR infra-red spectroscopy as well as XRF (x-ray fluorescence spectroscopy ), XPS (x-ray photo emission spectroscopy) and classical contact angle determination methods as part of a broad program to characterize the physical and chemical nature of stickies in pulp slurries with the goal of removing them or alleviating their pronounced tendency to deposit on machinery and paper products.