field emission scanning electron microscopy (FESEM)

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Original Article Effects of industrial noise on circumpulpar dentin - a field emission scanning electron microscopy and energy dispersive spectroscopy analysis

Original Article Effects of industrial noise on circumpulpar dentin - a field emission scanning electron microscopy and energy dispersive spectroscopy analysis

Abstract: Chronic exposure to Industrial Noise (IN), rich in Low Frequency Noise (LFN), causes systemic fibrotic transformation and sustained stress. Dental wear, significantly increased with exposure to LFN, affects the teeth particularly through the circumpulpar dentin. Our goal is to understand the consequences of IN exposure on the circumpulpar dentin of Wistar rats. 10 Wistar rats were exposed to IN for 4 months, according to an occupation- ally simulated time schedule and 10 animals were used as age-matched controls. The first and the second upper and lower molars of each animal were processed for observation by Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive Spectroscopy (EDS) analysis was performed. In exposed animals FESEM showed a 2.0 to 6.0 µm-dense mineral band between dentin and the pulp with no regular continuity with the tubules. This structure had a few tubules where the odontoblasts processes could be observed embedded within the band and collagen fibers were trapped inside. EDS analysis revealed that it was hydroxyapatite similar to dentin, with a higher carbon content. FESEM results show that the band may be tertiary reparative dentin formed by odontoblast-like cells, but the increased amount of carbon (EDS) could mean that it is sclerotic dentin. IN should be acknowledge as a strong stimulus, able to cause an injury to odontoblasts and to the formation of reparative tertiary dentin, in a process that may accelerate the aging of the teeth, either by direct impact of acoustic pressure pulsations or by increased stress and dental wear.
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Homoplastic occurrence of perforated pit membranes and torus-bearing pit membranes in ancestral angiosperms as observed by field-emission scanning electron microscopy

Homoplastic occurrence of perforated pit membranes and torus-bearing pit membranes in ancestral angiosperms as observed by field-emission scanning electron microscopy

Nine species were selected on the basis of their positions on a phylogenetic tree according to Angiosperm Phylogeny Group (Fig. 1) [13] and the availability of material. The origins of the materials used are listed in Table 1. Discs of stems or blocks of the outer layer of sapwood were taken from one or two trees of each species. The specimens were stored in 30 % ethanol either after fixation in FAA (a mixture of 37 % aqueous solution of formaldehyde, acetic acid and 50 % ethanol; 7:3:90, v/v) or without such treatment. We found no apparent differences in terms of the structure of interfiber pit membranes between speci- mens that had been treated with FAA and those that had not been treated with FAA prior to storage in 30 % ethanol. Field-emission scanning electron microscopy
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Hydrothermal Synthesis of Multiwall Carbon Nanotubes using Polystyrene: Purification and Characterization

Hydrothermal Synthesis of Multiwall Carbon Nanotubes using Polystyrene: Purification and Characterization

Abstract: In the present research the multiwall carbon nanotubes (MWCNTs) were synthesized by hydrothermal treatment of polystyrene in the presence of catalyst. In the typical synthesis, the carbon precursor polystyrene was reacted with catalyst iron particle in the closed condition with pressure of hydrothermal condition. The obtained product was purified with strong, mixture of acid, which can helpful for the removal of metal catalyst from the product. Further, the purified MWCNTs were sintered at 400 o C under nitrogen gas atmosphere to reduce the percentage of amorpous carbon. The MWCNTs were characterized by Field Emission Scanning Electron Microscopy (FESEM) for morphology study, EDX for elemental analysis, X-ray diffraction (XRD) study for crystalinity measurements, Raman spectroscopy to find out defects and graphitization of CNTs and Dynamic Light Scattering (DLS) process for particle size analysis.
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Nb2O5 Nanoparticles Synthesis by Chemical Surfactant-Free Methods: ltrasonic Assisted Approach

Nb2O5 Nanoparticles Synthesis by Chemical Surfactant-Free Methods: ltrasonic Assisted Approach

(Co) = 1.78901 A˚). Field emission scanning electron microscopy (FESEM) was employed with Mira 3- XMU. Average particle sizes and standard derivation (SD) of nanoparticles were measured by Digimizer software. FT-IR spectra were measured by Pekin-Elmer (model: spectrum 400).

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Fabrication and Characterization of Visible Light active Fe-TiO2 Nanocomposites as Nanophotocatalyst

Fabrication and Characterization of Visible Light active Fe-TiO2 Nanocomposites as Nanophotocatalyst

photocatalyst using a modified Sol-Gel process at ambient temperature. Crystallographic properties of nanocomposites were characterized by X-ray Diffraction (XRD). Surface morphology and mean particle size of nanocomposites were specified by Field Emission Scanning Electron Microscopy (FESEM) and light absorption spectrum of nanocomposites was evaluated by Diffuse Reflectance Spectra (DRS). XRD patterns revealed that Fe 3+ is successfully substituted by Ti 4+ in TiO 2 lattice and no rutile phase is

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Synthesis And Characterization Of Silver Nanoparticles Using Flower Extract Ofaerva Lanata And Evaluation Of Its Antimicrobial Activities

Synthesis And Characterization Of Silver Nanoparticles Using Flower Extract Ofaerva Lanata And Evaluation Of Its Antimicrobial Activities

The conventional methods of synthesis consists of physical, chemical and biological methods whereas these processes have various demerits such as high cost and energy demand use of toxic reductant agents and production of toxic waste. Recently, the green methods to synthesis nanoparticles has been proposed over conventional methods having a list of merits such as low cost, utilize less energy, produce less and nontoxic waste. Moreover green methods can control the size, shape and stability and they also offer simplicity and swiftness than other methods [12], [13], [14], [15]. The target of this research paper on the Aerva lanata flower (sirupeelai) which belongs to the family Amaranthaceae and its medicinal purposes. The flower is well known for its medical use since ancient times. In Ayurveda, the indian system of medicine, the Aerva lanata flower has been used as it attributes several medicinal properties. Aerva lanata is an excellent medicine for treating diseases related to stomach and the digestive system, and is a good remedy for stones in urinary bladder and kidney. Also it regulates the blood sugar level so the flower is good for diabetes patients. In this study we have successfully conducted a process of biosynthesis of AgNPs with extract of Aerva lanata. The obtained AgNPs were characterized by UV-Vis Spectrophotometer (UV), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic Light Scattering (DLS), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDAX). The nanoparticles were evaluated for antibacterial and antifungal activities. The antibacterial activities of the samples were studied on Staphylococcus auerus (MTCC25923), Bacillus subtilis (MTCC 2451) and Escherichia Coli (MTCC 25922) bacterial strains using disc- diffusion method. The antifungal test organisms used for study are Candida albicans (MTCC 3498) and Candida Vulgaris (MTCC 227).
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Surface plasma resonant effect of gold nanoparticles on the photoelectrodes of dye sensitized solar cells

Surface plasma resonant effect of gold nanoparticles on the photoelectrodes of dye sensitized solar cells

trode always exceeds that of the conventional DSSCs due to the presence of the Schottky barrier [17]. In this study, we prepared different shapes of gold nano- particles by seed-mediated growth method to apply on the photoelectrodes of the DSSCs. The gold nanoparti- cles and DSSCs were investigated by field emission scanning electron microscopy (FE-SEM), ultraviolet– visible (UV–vis) absorption spectra, current–voltage characteristics, electrochemical impedance spectroscopy (EIS), and incident photon conversion efficiency (IPCE) analyses to study the SPR effect of the gold nanoparti- cles on the photoelectrodes of the dye-sensitized solar cells.
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PREPARATION & IN VITRO EVALUATION OF INCLUSION COMPLEXES OF SIMVASTATIN TABLET WITH CYCLODEXTRINS

PREPARATION & IN VITRO EVALUATION OF INCLUSION COMPLEXES OF SIMVASTATIN TABLET WITH CYCLODEXTRINS

Filed emission scanning electron microscopy was used to determine the morphology of Simvastatin, HP-β-CD and simvastatin/HP-β-CD inclusion complex by physical mixture, kneading method, spray drying. The morphology of these samples was determined using the field emission scanning electron microscope (FESEM) FEI, NOVA NANOSEM 450. The pictures were taken at excitation voltage of 5 kv and magnification of 5000, 10000x. Samples were prepared by mounting approximately 0.5 mg of powder on to a silicon wafer via carbon tape to an aluminum stub. The powder was sputter-coated for 120 s at beam current of 20 mA with a 200 A˚ layer of chromium.
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Enhanced luminescence of Er+3-doped Zinc-Lead-Phosphate Glass embedded SnO2 nanoparticles

Enhanced luminescence of Er+3-doped Zinc-Lead-Phosphate Glass embedded SnO2 nanoparticles

(PbO, 99%), erbium oxide (Er 2 O 3 , 99.8%) were put in a platinum crucible and melted at 990C for one hour in a furnace under atmospheric pressure. The samples were placed between two brass plates for quenching and then cooled down at room temperature. The phase purity and phase structure of powder samples were characterized by the X-ray powder diffraction (patterns) with Cu-K α radiation operating at 40 kV, 30mA at room temperature using Siemens Diffractometer D5000, equipped with diffraction software analysis. The morphology was examined by using field emission scanning electron microscopy. The measurement of the optical absorption and the absorption edge were done by using the UV-Vis- NIR scanning spectrophotometer. The Perkin Elmer LS55 Luminescence spectrometer was used to determine the photoluminescence properties of the doped glass.
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Enhanced efficiency of dye sensitized solar cells doped with green phosphors LaPO4:Ce, Tb or (Mg, Zn)Al11O19:Eu

Enhanced efficiency of dye sensitized solar cells doped with green phosphors LaPO4:Ce, Tb or (Mg, Zn)Al11O19:Eu

photoelectrodes could lead to higher efficiency in dye- sensitized solar cells. Field emission-scanning electron microscopy (FE-SEM) was used to determine the morph- ology of this hybrid photoelectrode. The absorption and luminescence properties of dye and green phosphor ceramics were investigated using UV spectrophotometry and photoluminescence spectrometry. Electrochemical

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Structural and Optical Characterization of Tungsten Oxide Nanoparticles by Wet Chemical Technique

Structural and Optical Characterization of Tungsten Oxide Nanoparticles by Wet Chemical Technique

Wet chemical method from sodium tungstate dihydrate and hydrochloric acid. Average crystallite size of the synthesized nanoparticles calculated from Debye – Scherrer equation was around 36 nm. Field Emission Scanning Electron Microscopy confirms the rod like morphology. Optical bandgap was found to be 2.61 eV confirmed from UV – Vis studies. From PL spectroscopy the energy distribution of emitted photons were measured.

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One Step Mask Etching Strategy Toward Ordered Ferroelectric Pb(Zr0 52Ti0 48)O3 Nanodot Arrays

One Step Mask Etching Strategy Toward Ordered Ferroelectric Pb(Zr0 52Ti0 48)O3 Nanodot Arrays

The nanostructure characterization was carried out ex situ with a field-emission scanning electron microscope (FE-SEM; Zeiss Ultra 55). Atomic/piezoresponse force microscopy (AFM/PFM; Cypher™, Asylum Research) was used to characterize the surface morphologies and the ferroelectric properties of PZT nanodot arrays. The crystallization properties of the PZT nanodots were in- vestigated using X-ray diffraction (XRD; Philips X’Pert Pro) with an X-ray wavelength of 0.15406 nm. The Raman spectrums were measured at room temperature by the inVia Reflex Raman microscope (Renishaw Corp.) with an excitation wavelength of 633 nm, and the laser power was set to 10 % of its maximum.
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Preparation of Lead Polymer Nano composite For Nuclear Shielding Applications

Preparation of Lead Polymer Nano composite For Nuclear Shielding Applications

Abstract— Nano Lead was prepared using polyvinyl alcohol as a process control agent in a high energy ball mill. The crystallite size and the micro-strain of the produced nano-Pb/PVA at different milling times were calculated from X-ray diffraction patterns. Field Emission Scanning and High Resolution Transmission electron microscopy were used to characterize the progress of Pb particles morphology through the milling process and to ensure the nanometric size of the milled nano-Pb/PVA then mixed with Polypropylene for gamma ray attenuation.
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Green Synthesis of Silver Nanoparticles by Using Pomegranate and Their Antimicrobial Activity-A Revolution

Green Synthesis of Silver Nanoparticles by Using Pomegranate and Their Antimicrobial Activity-A Revolution

Transmission electron microscopy, Scanning electron microscopy and atomic force microscopy techniques can be used for morphological studies of nanoparticles, which were used by different researchers to know the shape and size of nanoparticles but before the morphological studies, there is need to standardize the synthesis of nanoparticles using plants or their extracts. The formation of nanoparticles can be characterized by the use of UV-visible spectroscopy. As shown in table 2, silver nano particles synthesized by the use of various parts of pomegranate showed the absorption Peaks (λmax. Value) in the range of 390-480 nm. Figure 1 shows how the absorption peak come in the UV-visible spectra for silver nanoparticles[46].With the increase in time and concentration of plant extract with the salt ions clearly indicate the formation of nanoparticles.
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Dark side illuminated: imaging of Toxoplasma gondii through the decades

Dark side illuminated: imaging of Toxoplasma gondii through the decades

A study showing that tissue cysts containing bradyzoites was also published by Janku [5]. Again, he reported that T. gondii was most strongly stained with haemotoxy- lin and eosin (H&E), but that staining with Giemsa, Mallory (a mixture of three dyes: acid fuchsin, aniline blue, and orange G, used to reveal red nuclei, pink cytoplasm and blue extracellular matrix), or Biondi (a mixture of aurantia, acid fuchsin and methyl-green to reveal pale cytoplasm and greenish chromatin) methods of staining also produced clear images. Bradyzoites (Figure 1C) within tissue cysts (Figure 1D) contain many granules of amylopectin, perhaps as a source of energy that is not present in tachyzoites, that stain red with PAS reagent [8]. This could make PAS a more specific stain for the presence of bradyzoites. The cyst wall is only slightly stained by PAS reagent, but heavily stained by Palmgren silver. Curiously, methenamine silver does not stain the cyst wall at all, suggesting that it is devoid of polysaccha- rides [8]. Although silver and PAS staining make it easier to distinguish a tissue cyst compared to Geimsa or H&E staining, it has been suggested that light microscopy is an inferior method for identifying cysts within tissue as they are easily confused with groups of tachyzoites or other parasites. A drawback of light microscopy that contributes to this confusion is that although a large increase in magnification is possible using visible light, resolution is limited. It has also been pointed out that it is unclear when the cyst wall is capable of appearing as silver posi- tive, so more specific staining procedures could be used to identify a tissue cyst [6]. For example, it is now thought that Samuel Darling was the first to describe Toxoplasmosis in a human adult. However, at the time he diagnosed his patient with Sarcosporidum, which can easily be confused with a T. gondii tissue cyst when stained with H&E [9]. (Darling published illustrations with his original manuscript, not photographic images). Despite these reservations, the above staining methods
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Comparative Foliar Epidermal Studies in Cymbopogon citratus and Cymbopogon schoenanthus In Sudan

Comparative Foliar Epidermal Studies in Cymbopogon citratus and Cymbopogon schoenanthus In Sudan

Scanning electron microscopy showed that the surfaces of the two species contain large quantities of wax (plate 3 A and B) , with larger quantities of wax in C. citratus compared to C. scheonanathus. The adaxial surfaces of the two species are denser with wax (with large lumps) small conical hairs are projecting from C. schoenanthus , they are covered with silica depositions and they are longer on C. citratus. The stomata are elongated with raised rim and very long narrow apertures.

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A targeted 3D EM and correlative microscopy method using SEM array tomography

A targeted 3D EM and correlative microscopy method using SEM array tomography

Using electron microscopy to localize rare cellular events or structures in complex tissue is challenging. Correlative light and electron microscopy procedures have been developed to link fluorescent protein expression with ultrastructural resolution. Here, we present an optimized scanning electron microscopy (SEM) workflow for volumetric array tomography for asymmetric samples and model organisms (Caenorhabditis elegans, Drosophila melanogaster, Danio rerio). We modified a diamond knife to simplify serial section array acquisition with minimal artifacts. After array acquisition, the arrays were transferred to a glass coverslip or silicon wafer support. Using light microscopy, the arrays were screened rapidly for initial recognition of global anatomical features (organs or body traits). Then, using SEM, an in-depth study of the cells and/or organs of interest was performed. Our manual and automatic data acquisition strategies make 3D data acquisition and correlation simpler and more precise than alternative methods. This method can be used to address questions in cell and developmental biology that require the efficient identification of a labeled cell or organelle.
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Synergistic antifungal effect of chitosan-stabilized selenium nanoparticles synthesized by pulsed laser ablation in liquids against <em>Candida albicans</em> biofilms

Synergistic antifungal effect of chitosan-stabilized selenium nanoparticles synthesized by pulsed laser ablation in liquids against <em>Candida albicans</em> biofilms

treated with SeNPs at 21.7 ppm (Figure 4C) has changes in morphology (red arrows). Yeasts treated with CS-SeNPs at 3,500–3.5 ppm, respectively, show major changes in mor- phology and structure. Red arrows show major deformation of the yeast cells and the polycationic polymer adhered to the negatively charged outer CW (Figure 4D). Bright-field (BF) scanning transmission electron microscopy (STEM) image shows CS-SeNPs entering the yeast (Figure 4E), CS adhered to the outer CW, with SeNPs (darker dots).

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[B.S._Murty,__P._Shankar,__Baldev_Raj,__B_B_Rath,_(b-ok.org).pdf

[B.S._Murty,__P._Shankar,__Baldev_Raj,__B_B_Rath,_(b-ok.org).pdf

Fibre-optic sensors provide useful tools for remote in situ monitoring. Fibre-optic sensors can be used for sensing intracellular/intercellular physiological and biological species. Scientists have developed nanosensors for the in situ intracellular measurement of single cells using antibody-based nanoprobes. Incubation of cells with fluorescent dyes or nanoparticles and their interaction is commonly studied using microscopy techniques. During incubation of a dye or nanoparticle into a cell, it is generally transported to intracellular sites. With optical nanosensors, excitation light can be delivered to specific locations inside cells. In these nanosensors, the monitoring process is almost non-invasive. Combined with the exquisite molecular recognition of antibody probes, nanosensors could serve as powerful tools for exploring biomolecular processes in sub-compartments of living cells. They have a great potential to provide the necessary tools to investigate the multi-protein molecular machines of complex living systems and the complex network that controls the assembly and operation of these machines in a living cell. It is expected that nanosensors equipped with nanotool sets will soon be developed for tracking, assembly and disassembly of multi-protein molecular machines. Scientists have so far been investigating the genes and proteins by breaking the cell apart and studying their individual components in vitro. It is expected that nanosensors would permit research on entire networks of genes and proteins in the living cell in vivo.
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Combining scanning probe microscopy and x ray spectroscopy

Combining scanning probe microscopy and x ray spectroscopy

In Figure 2a we present the XAFS-XEOL spectrum obtained with the apparatus at ESRF ID03 line of a ZnO thin layer (~400 nm), prepared by Zn sputtering on a silicon substrate, followed by a 900°C annealing in air. The threshold, localized at 9664 eV, is characteristic of visible light emitted by Zn atoms after X-Ray absorp- tion. This spectrum is compared with that of the same sample (Figure 2b, bottom) and with that of a commer- cial stoichiometric ZnO powder sample for reference (Figure 2b, top, shifted), obtained in conventional XAFS-XEOL spectroscopy, in far field, at the same beamline. Spectra shown in Figure 2b are in very good agreement in terms of both peak positions and relative magnitudes measured with respect to the average signal above threshold. This indicates that the ZnO sputtered layer is stoichiometric. The great concordance between spectra Figure 2a and Figure 2b validates the instrument concept.
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