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Custom built in-situ ultrasonic aging equipment was used to investigate the precipitation hardening response in a commercial WE43 alloy at 210°C. Three power levels (100, 300, 400 W) with time intervals of 15, 30, and 60 s between sonication were used to measure the change in hardness. Aging response was 24 times faster, decreasing the time to achieve peak hardness from 48 hrs during conventional aging to 2 hrs under the influence of ultrasonic waves. While higher power increased the peak hardness, shortening the interval time from 30 to 15 s did not have any influence. Transmission electron micrographs revealed well-developed β1 variants in as little as 15 minutes for ultrasonically aged samples, which was the reason for enhanced age hardening response.

Summary Nutrients and temperature are the major elements in maintaining stable endosymbiotic relationships. The mechanisms and response of cultured Symbiodinium cells in the absence of nitrogen, and at various temperatures are still unclear. The present study investigated the influence of different temperatures and nitrogen-deprivation on free-living Symbiodinium cultures. The physiological responses of free-living Symbiodinium cells cultured at different temperatures during nitrogen deprivation under a 12:12 h light:dark were measured. Symbiodinium cell growth was significantly lower in response to lower temperatures. Transmission electron micrographs (TEMs) revealed the formation of lipid droplets induced by nitrogen deprivation under different temperatures. The results of this study will increase our understanding of adaptive responses occurring in Symbiodinium under environmental stress.

Junctions between carbon nanotubes and flat or curved graphene structures are fascinating for a number of reasons. It has been suggested that such junctions could be used in nanoelectronic devices, or as the basis of three-dimensional carbon materials, with many potential applications. However, there have been few detailed experimental analyses of nanotube-graphene connections. Here we describe junctions between nanotubes and graphene shells in a material produced by passing a current through graphite. Transmission electron micrographs show that the junction angles are not random but fall close to multiples of 30°. We show that connections with these angles are the only ones which are consistent with the symmetry of the hexagonal lattice, and molecular models show that a continuous lattice requires the presence of large carbon rings at the junction. Some of the configurations we propose have not been previously considered, and could be used to construct new kinds of three-dimensional carbon architecture. We also discuss the possible formation mechanism of the junctions.

In this work, gold nanomaterials were obtained using aqueous extracts of black carrots varying the molar ratio between the extract and the gold precursor salt (1:10, 1:5 and 2:5). Additionally, Au nanoparticles were obtained by the Turkevich method as reference material (Au Turkevich). Transmission electron micrographs indicated that a 1:5 ratio allowed to obtain a mixture of gold shapes like triangular, plate, rod, wire, and hemispherical shapes. The electrocatalytic evaluation for 0.5 M glycerol electro-oxidation indicated that Au (1:5) displayed higher current density (298.26 vs. 230.25 mA mg−1), and a more negative onset potential (ΔE = 150 mV) than Au Turkevich. In addition, Au (1:5) displayed higher current density during the electro-oxidation of 1 M crude glycerol (466.91 vs. 244.73 mA mg−1) with a similar potential difference. The improvement in activity and durability presented by Au (1:5) was attributed to the abundance of {1 0 0} facets as was determined by X-ray diffraction and HR-TEM.

The present study describes an environment-friendly biosynthesis of silver nanoparticles from marine red algae Spyridia filamentosa through the bio-reduction process. S. filamentosa have significantly high amounts of phytochemicals and secondary metabolites responsible for the formation of AgNPs. UV–Vis spectra results showed corresponding AgNPs peak at 420 nm. Transmission electron micrographs showed well dispersed spherical particles with the 20–30 nm in size. FT-IR and XRD results revealed the characteristics of AgNPs. Further, the AgNPs displayed potential antibacterial activity against Staphylococcus sp. (KC688883) and Klebsiella sp. (KC899845), and anticancer activity against MCF-7 cells.

We prepared a new size-stable UV-cured material by loading a radical scavenger, 4-methoxyphenol (MEHQ), into halloysite nanotubes (HNTs) to improve the size-stability of UV-cured products. Loading the MEHQ into halloysite nanotubes was intended to protect the curing reaction from the typical inhibitive influence of a radical scavenger. After the curing process, heating treatment was performed on the cured products to accelerate the release of MEHQ from the halloysite lumen. The Brunauer-Emmett-Teller tests and transmission electron micrographs showed that MEHQ was successfully loaded into the halloysite lumen. The photopolymerization kinetic curves of composites revealed that adding the MEHQ-loaded halloysite nanotubes (HNTs-M) into UV-cured materials enabled faster photopolymerization rate than adding a simple mixture of HNTs and MEHQ. With MEHQ loaded in HNTs, the inhibition influence of MEHQ could be reduced. The results of the size-stability test showed that composites with HNTs-M underwent lower deformation during daily use than neat cured materials. In particular, the volume shrinkage of the composites with 8 wt% HNTs-M in daily use was decreased by 51.3%. The results of the release experiment showed that the release rate of MEHQ could be increased through heating treatment. This method may be used to improve the size-stability of UV-curable materials in the future.

Transmission electron micrographs show the branchial epithelium of the ascidian Ciona intestinalis to be composed of three kinds of cells: ciliated, parietal, and "dark." Absorptive processes of phagocytosis appear in ciliated and parietal cells; moreover, apocrine-like secretion is evident exclusively in the parietal cells. Finally, the occurrence of secretory cells in the branchial epithelium suggests a digestive role of the ascidian branchial sac.

Monodispersed platinum nanoparticles (Pt-NPs) with an average diameter dTEM 3.1±1.0 nm were synthesized by EtOH reduction method in the presence of an organic polymer poly (vinylpyrrolidone) (PVP) with an average molecular weight of 40,000. Using this particles as seed, size tunable Pt-NPs of dTEM 3.1±1.0 nm to 5.7±1.6 nm with sufficient monodispersity were synthesized by multiple step seeding growth. Formation of Pt-NPs was confirmed by the UV-visible absorption spectra. Transmission electron micrographs (TEM) and powder X-ray diffraction (XRD) patterns confirmed that the particles were single crystalline with fcc crystal geometry.Bangladesh J. Sci. Ind. Res. 50(2), 87-92, 2015

Systematic research on Monomolecular Layer of Copper (II) Phthalocyanine (CuPc) and porphyrin (Por) derivatives bas been done. In this paper an attention is focused upon the molecular orientation in monomolecular layer of some symmetrically and asymmetrically substituted CuPc and Por by means of the surface pressure-area (π-A) isotherm method, the transmission electron micrographs (TEM) , polarized UV-visible spectra.

Encarsia sophia (Hymenoptera: Aphelinidae) is a parasitoid utilized for biological control of Bemisia tabaci , with selection of prey aided by chemoreceptor organs. The morphology and distribution of the antennal sensilla (chemoreceptors) of E. sophia were examined using Transmission electron micrographs. The total antennal length for E. sophia was 429.28 ± 0.95 μm for females and 437.19 ± 8.21 for males, and each antennae was found to consist of seven sensilla of different types. Both sexes possessed sensilla chaetica, sensilla trichodea, basiconic capitate peg sensilla, multiporous grooved-surface placoid sensilla (MG-PS), uniporous rod-like sensilla, nonporous finger-like sensilla, and sensilla coeloconica. Transmission electron micrographs of longitudinal sections of female antennae showed that they were composed of fat body, cuticle, mesoscutello-metanotal muscles, neurons, and glandular tissue, and cross-sections of the basal MG-PS showed sensillar lymph cavities and dendrites. The MG-PSs were imbedded in an electron-dense mass with cuticular invaginations which acted as pores that connected to a central lumen. The possible function of each type of sensilla is discussed.

Fe2O3 nanoparticles with polyhedral morphology were synthesized by a hydrothermal method. Parallelepiped -Fe2O3 nanoparticles with a narrow size distribution were was successfully synthesized by hydrothermal method. The structural and morphological properties of -Fe2O3 nanoparticles were characterized by X-ray diffract meter (XRD), Scanning electron microscope (SEM), and transmission electron micrograph (TEM). The sensing capability of the polyhedral -Fe2O3 nanoparticles was investigated, the results showed that The polyhedral nanoparticles possessed the linearly response current related to the concentration of H2O2 in wide range concentration.

This work described the rapid synthesis procedure for TiO2/MWCNT nanocatalyst using a modified microwave method. Transmission electron micrographs suggested TiO2 nanoparticles were strongly attached to the MWCNT. The surface area of the nanocatalysts determined by the Brunauer–Emmett–Teller method proved that the hybrid nanocatalyst have higher surface area (262.3 m2/g) than pristine TiO2 (172.3 m2/g). The photocatalytic activity of the nanocatalyst was investigated under visible light (VL) illumination by studying the degradation of methylene blue dye (MB) with concentration of 10 ppm in 100 mL H2O as a model compound. The results showed that the degradation efficiency obtained by using TiO2/MWCNTs is about 40% higher than bare TiO2. This signification enhancement was attributed to higher surface area and the ability of MWCNTs to act as a visible-light photosensitising agent revealing potential application in the treatment of wastewater.

A classical thermodynamic approach has been used for describing the pseudomorphic growth in Mg/Nb multilayer films. The bi-phase diagram of these films has been predicted theoretically and the predictions were verified experimentally by growing multiple Mg/Nb thin films that were characterized through high resolution transmission electron micrograph (HRTEM) and X-ray diffraction (XRD) measurement. The good agreement between predictions and experiments shows that the stability of multilayer films can be explained through simple thermodynamic analysis on the competition between bulk and interfacial energies.

Streptococcosis caused by Streptococcus iniae has become one of the most serious marine and freshwater aquatic diseases in the past decade, causing large losses in farmed and wild fish worldwide. In this study, we performed an ultrastructural study of major lesions in gilthead seabream Sparus aurata and red porgy Pagrus pagrus experimentally infected with the S. iniae IUSA-1 strain, isolated in a natural outbreak in Spain in the mentioned species. The transmission electron micrographs revealed the resistance of this pathogen inside the phagosome, indicating that the macrophage may provide a significant bacterial reservoir for continuing infection, disease dissemination, and tissue injury by crossing the blood-brain barrier.

FeNi3\SiO2\HPG\PbS magnetic nanoparticles (MNPs) catalyst was readily prepared from inexpensive starting materials in aqueous media which catalyzed the synthesis 2-amino-4H-chromene via intermittent microwave irradiation. X-ray diffraction, transmission electron micrographs, and scanning electron micrographs were employed to characterize the properties of the synthesized FeNi3\SiO2\HPG\PbS MNPs. High catalytic activity and ease of recovery from the reaction mixture using external magnet and several reuse times without significant losses in performance are additional eco-friendly attributes of this catalytic system.

Transmission electron microscopy has been used to identify poly-3-hydroxybutyrate (PHB) granules in cyanobacteria for over 40 years. Spherical inclusions inside the cell that are electron-transparent and/or slightly electron-dense and that are found in transmission electron micrographs of cyanobacteria are generally assumed to be PHB granules. The aim of this study was to test this assumption in different strains of the cyanobacterium Synechocystis sp. PCC 6803. Inclusions that resemble PHB granules were present in strains lacking a pair of genes essential for PHB synthesis and in wild-type cells under conditions that no PHB granules could be detected by fluorescence staining of PHB. Indeed, in these cells PHB could not be demonstrated chemically by GC/MS either. Based on the results gathered, it is concluded that not all the slightly electron-dense spherical inclusions are PHB granules in Synechocystis sp. PCC 6803. This result is potentially applicable to other cyanobacteria. Alternate assignments for these inclusions are discussed.

BaSi2 epitaxial films were grown on Si(111) substrates by a two-step growth method including reactive deposition epitaxy (RDE) and molecular beam epitaxy (MBE). To enlarge the grain size of BaSi2, the Ba deposition rate and duration were varied from 0.25 to 1.0 nm/min and from 5 to 120 min during RDE, respectively. The effect of post-annealing was also investigated at 760 °C for 10 min. Plan-view transmission electron micrographs indicated that the grain size in the MBE-grown BaSi2 was significantly increased up to approximately 4.0 μm, which is much larger than 0.2 μm, reported previously.

Silver nanoparticles (SNP) incorporated potassium oleate (KOL) soap by in situ reduction of silver nitrate by trisodium citrate (TSC) was described. Novel incorporation method of SNP into the natural rubber latex foam (NRLF) was successfully carried out by mixing 4 parts per hundred rubber (pphr) of SNP incorporated KOL soap in to the natural rubber latex (NRL) compound. UV-Visible spectrophotometer analysis, particle size analysis data and transmission electron micrograph analysis proved the modified KOL soap consisted of stable mono-dispersed nanometer size silver particles. SEM/EDX analysis of a latex film made out with modified NRL compound by SNP incorporated KOL soap shows nanosized silver particles inside it. Modified KOL and final product of modified NRLF by SNP incorporated KOL soap tested for antimicrobial properties against Escherichia coli (E. coli). The resultant KOL itself can inhibit Gram negative E. coli bacterium in a very strong manner. Inhibition of the same strain of E. coli bacterium ...

Fe2O3–SnO2 nanocomposites (NCs) were prepared by hydrothermal and sonochemical methods. Transmission electron micrographs confirmed that the composites comprise nanoparticles. Energy-dispersive X-ray analyses revealed compositions of 25 at.% Sn and 22 at.% Fe for hydrothermally prepared NC (HNC) and 4 at.% Sn and 56 at.% Fe for sonochemically prepared NC (SNC). X-Ray diffractograms revealed rutile SnO2, γ-Fe2O3, and FeO(OH) as components of HNC, and rutile SnO2, γ-Fe2O3, β-Fe2O3 and FeO(OH) of SNC. Both NCs absorb visible light and display red emission. The solid-state impedance spectrum for HNC is a half-semicircular arc and SNC exhibits a quasi-linear relationship between Z′′ and Z′. Both NCs are ferromagnetic. The saturation magnetization of HNC is much less than that of the SNC, which in turn is far less than that of the γ-Fe2O3 precursor. Both NCs display visible light photocatalysis and HNC is a better photocatalyst than SNC. Furthermore, both NCs exhibit bactericidal activity.

The reliable and reproducible quantitative image analysis of digital micrographs from high resolution transmission electron microscopy (HRTEM) of soot has been an area of interest since the early nineties. Since the resolution of HRTEM images is usually sufficient to carry out structural measurements at the atomic level, the information obtained from these images is very valuable as it potentially yields insight into very specific soot oxidation processes; however, extracting physically meaningful, reliable, accurate and statistically robust data from HRTEM images is not an easy process. Data extraction is hindered by the presence of overlapping structures, varying focus, contrast, illumination levels and noise in the images. In this paper a novel image analysis framework is presented to address these issues and explore the possibility of the extraction of high-fidelity structural data from HRTEM soot images. Emphasis is on the analysis of images of mostly amorphous, poorly ordered soot structures, as these are the most difficult to analyze.

We describe a new species of Mallomonas, M. asymmetrica sp. nov., belonging to the class Synurophyceae, was found in acidic clear water, in an oligotrophic water body, located in the National Wetland Preserve of Zhenbaodao, Heilongjiang, China. M. asymmetrica, I would suggest to raise the new section for this species, but need more data (e.g. molecular data) is available. Scales are highly asymmetric, with one lateral edge of the V-rib being much longer than the other, and the anterior flanges of both the body scales and the rear scales showed a row of regularly spaced small pores along the anterior submarginal rib. The ultrastructure of the scales and bristles of this organism is described and illustrated by transmission electron micrographs.

Amino-dextran-functionalized superparamagnetic iron oxide nanoparticles (SPION) were synthesized by two-steps: Dextran-modified SPION was obtained by “one-step” co-precipitation method. Then, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS) was added to the resultant dextran-SPION to prepare amino-dextran-functionalized SPION (AEAPS/Dex-SPION). The particles were characterized by vibrating sample magnetometer (VSM), transmission electron micrographs (TEM), atomic force micrographs (AFM), gas chromatography and atomic absorption spectrophotometry. The size of the modified particles varied in a range of 30 to 40 nm and did not change significantly after modification. The binding rate of AEAPS was 91.15%. A monoclonal antibody against S100 (anti-S-100), a gold standard for the diagnosis of melanocytic lesions, was conjugated to the AEAPS/Dex-SPION to prepare immuno-SPION. From the result in melanoma B16 cell, the immuno-SPION was proven to have a bio-targeting activity. Such AEAPS/Dex-SPION might be ve...

Transmission electron micrographs of glycogen extracted from healthy mouse hearts reveal aggregate structures around 133 nm in diameter. These structures are similar to, but on average somewhat smaller than, the α-particles of glycogen found in mammalian liver. Like the larger liver glycogens, these new particles in cardiac tissue appear to be aggregates of β-particles. Free β-particles are also present in liver, and are the only type of particle seen in skeletal muscle. They have diameters from 20 to 50 nm. We discuss the number distributions of glycogen particle diameters and the implications for the structure-function relationship of glycogens in these tissues. We point out the possible implications for the study of glycogen storage diseases, and of non-insulin dependent diabetes mellitus.

Corn fiber gum (CFG) was previously conjugated with bovine serum albumin (BSA) via peroxidase treatment to improve its emulsifying properties. The current study was undertaken to evaluate the molecular characteristics of CFG-BSA conjugates prepared at different CFG/BSA weight ratios of 10:1, 4:1, 1:1, and 1:4. After the peroxidase treatment, CFG-BSA mixtures at weight ratios of 10:1 and 4:1 showed an increase in molecular weight from 200 and 193kDa to 218 and 223kDa respectively. But for CFG-BSA mixtures at weight ratio of 1:4, their molecular weight decreased. Peroxidase treated CFG-BSA mixtures had a more compact but rougher surface morphology as compared with the untreated as revealed by scanning electron microscopy. At lower CFG to BSA weight ratio (1:4), particles of CFG-BSA conjugates appeared to be elongated while at higher CFG to BSA weight ratio (10:1), they were approximately spherical in transmission electron micrographs.

Because of the weak penetrating power of electrons, the signal-to-noise ratio of a transmission electron micrograph (TEM) worsens as section thickness increases. This problem is alleviated by the use of the scanning transmission electron microscopy (STEM). Tomography analyses using STEM of thick sections from yeast and mammalian cells are of higher quality than are bright-field (BF) images. In this study, we compared regular BF tomograms and STEM tomograms from 500-nm thick sections from hypertrophied Golgi stacks of alfalfa root cap cells. Due to their thickness and intense heavy metal staining, BF tomograms of the thick sections suffer from poor contrast and high noise levels. We were able to mitigate these drawbacks by using STEM tomography. When we performed STEM tomography of densely stained chloroplasts of Arabidopsis cotyledon, we observed similar improvements relative to BF tomograms. A longer time is required to collect a STEM tilt series than similar BF TEM images, and dynamic autofocusing required for STEM imaging often fails at high tilt angles. Despite these limitations, STEM tomography is a powerful method for analyzing structures of large or dense organelles of plant cells.

Tungsten carbide nano particles were formed by carburizing tungsten/tungsten oxide/non-stoichiometric tungsten oxide particles obtained from a wire explosion process with multi walled carbon nano tubes (MWCNT). The produced powder is confirmed to be hexagonal tungsten carbide from wide angle X-ray diffraction analysis. Carburization of tungsten nano particles with MWCNT shows the presence of tungsten sub-carbides in the produced tungsten carbide particles. Transmission electron micrographs show that the tungsten carbide particles are of spherical shape and the geometric mean size of the particles obtained is about 19 nm. � 2012 Elsevier Ltd.