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101.
In order to observe intracellular structures by scanning electron microscopy, excess cytoplasmic matrix must be removed from the fractured surface of cells. Previously we reported an Osmium-DMSO-Osmium method devised for this purpose. This method is very effective in revealing intracellular structures, but requires osmium tetroxide for initial fixation with some consequent disadvantages. In the present study, a revised Osmium-DMSO-Osmium method is reported, in which an aldehyde mixture is used as the initial fixative instead of osmium tetroxide. As fixation is carried out by perfusion in this revised method, better preservation of fine structures is achieved than by the original method, especially in the central nervous tissue which tends to suffer from post-mortem degeneration. Moreover this method can be applied to cytochemical studies of intracellular structures with a scanning electron microscope (SEM). In this study, acid phosphatase of lysosomes is demonstrated in a coloured SEM micrograph. 相似文献
102.
Majid Mohammadi Seid Ahmad Jenabali Jahromi Sirus Javadpour Akira Kobayashi Kurosh Shirvani 《Oxidation of Metals》2012,78(1-2):17-30
Conventional and gradient CoNiCrAlYSi coatings were produced by using low vacuum plasma spray and an additional step of diffusional over aluminizing (pack cementation) techniques on an Inconel-738 substrate. Hot corrosion of these coatings was investigated using Na2SO4–20wt%NaVO3 molten salt at 880?°C for 800?h. Hot corrosion rate was determined by measuring the weight gain of the specimens at regular intervals for a duration of 20?h. X-ray diffraction, field emission scanning electron microscopy and electron probe micro analysis techniques were used to determine the nature of phases, investigation of the thermally grown oxide, examination of the surface attack and determination of the elemental distribution. The gradient coating showed better performance by re-healing alumina scale due to its possession of more β phase as Al reservoir. Results indicated that pack cementation process caused an increase in amount of aluminum-rich β phase and better hot corrosion properties of gradient coatings owing to the Al enrichment in the outer layer and rapid formation of protective oxide on the surface. 相似文献
103.
Jittraporn Wongsa-Ngam Megumi Kawasaki Terence G. Langdon 《Journal of Materials Science》2012,47(22):7782-7788
A copper alloy, Cu–0.1 %Zr, was subjected to severe plastic deformation at room temperature using quasi-constrained high-pressure torsion. Disks
were strained through different numbers of revolutions up to a maximum of ten turns under an applied pressure of 6.0 GPa and
then examined to evaluate the evolution in the Vickers microhardness, Hv, and the microstructure. The results show lower values
of Hv in the center regions of the disks in the early stages of processing but a gradual evolution to a high degree of hardness
homogeneity after five and ten turns. Under conditions of hardness homogeneity, the distributions of the grain boundary misorientations
are essentially identical at the center and the periphery of the sample. Homogeneity was further confirmed by conducting tensile
testing at elevated temperatures where similar stress–strain curves and similar elongations to failure were recorded after
processing through five and ten turns of HPT. 相似文献
104.
In vivo measurement of swallowing by monitoring thyroid cartilage movement in healthy subjects using thickened liquid samples and its comparison with sensory evaluation
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105.
Yasutoshi Ban Hideya Suzuki Shinobu Hotoku Tomohiro Kawasaki Hiroshi Sagawa Nao Tsutsui 《溶剂提取与离子交换》2019,37(1):27-37
Single-stage batch experiments to reveal the extraction properties of N,N,N’,N’-tetradodecyldiglycolamide (TDdDGA) for Y, La, Eu, Nd, and Am in nitric acid were carried out. The distribution ratios of Y, Eu, Nd, and Am exceeded 10 when the nitric acid concentration was 1–2 mol/dm3 (M), and the distribution ratio of La was 5.5 when the nitric acid concentration was 2 M. A continuous counter-current experiment using 0.1 M TDdDGA diluted with n-dodecane was performed using mixer-settler extractors installed in a hot cell. Nitric acid with a concentration of 2.1 M containing minor actinides (MAs: Am and Cm), rare earths (REs: Y, La, Nd, and Eu), and other fission products (Sr, Cs, Zr, Mo, Ru, Rh, and Pd) was fed to the extractor. TDdDGA effectively extracted MAs and REs from the feed, while other fission products were barely extracted. The extracted MAs and REs were back-extracted by bringing them in contact with 0.02 M nitric acid, and they were collected as the MA–RE fraction. The results indicated that more than 98% of Am and Cm in the feed were recovered in the MA–RE fraction. The proportions of Y, La, Nd, and Eu in the MA–RE fraction were 94.0%, 99.9%, 99.9%, and 86.9%, respectively. 相似文献
106.
A microtubule gliding assay is a biological experiment observing the dynamics of microtubules driven by motor proteins fixed on a glass surface. When appropriate microtubule interactions are set up on gliding assay experiments, microtubules often organize and create higher-level dynamics such as ring and bundle structures. In order to reproduce such higher-level dynamics on computers, we have been focusing on making a real-time 3D microtubule simulation. This real-time 3D microtubule simulation enables us to gain more knowledge on microtubule dynamics and their swarm movements by means of adjusting simulation parameters in a real-time fashion. One of the technical challenges when creating a real-time 3D simulation is balancing the 3D rendering and the computing performance. Graphics processor unit (GPU) programming plays an essential role in balancing the millions of tasks, and makes this real-time 3D simulation possible. By the use of general-purpose computing on graphics processing units (GPGPU) programming we are able to run the simulation in a massively parallel fashion, even when dealing with more complex interactions between microtubules such as overriding and snuggling. Due to performance being an important factor, a performance model has also been constructed from the analysis of the microtubule simulation and it is consistent with the performance measurements on different GPGPU architectures with regards to the number of cores and clock cycles. 相似文献
107.
108.
Asymmetric autocatalysis with amplification of enantiomeric excess is found in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde using pyrimidyl alkanol as an asymmetric autocatalyst. Asymmetric autocatalysis has been employed as a method for clarifying the origin of homochirality. Circularly polarized light, inorganic chiral crystals and statistical fluctuation of enantiomeric imbalance act as chiral initiators in asymmetric autocatalysis to afford highly enantioenriched products. We have investigated asymmetric autocatalysis using chiral crystals formed from achiral and racemic compounds as an origin of chirality. Absolute control of the crystal chirality of cytosine was achieved by the removal of crystal water. Enantioselective carbon-carbon bond formation at the enantiotopic crystal face of aldehydes was established using diisopropylzinc vapor. In addition, asymmetric autocatalysis triggered by chiral compounds arising from H, C and O isotope substitution has been achieved. 相似文献
109.
This study clarifies the absorption behavior of micro-droplets of water on treated paper to support the design of functional
microstructures, such as electronics and micro-fluid channels, on paper. The period of time between when a micro-droplet of
water ejected from an ink-jet head lands on the paper’s surface and its complete disappearance by absorption was defined as
the micro-sizing degree (MSD), and an MSD measurement method was established. The MSD was evaluated using microscopic high-speed
video images of the side view recorded every millisecond. Several grades of commercially available ink-jet paper media and
laboratory sheets having different levels of water repellency prepared from a pulp and a sizing agent were examined. The MSD
of commercial ink-jet papers, which are known to absorb water very quickly, was 3–6 ms. Weakly sized laboratory sheets exhibited
a lower MSD of 2–3 ms. The absorption behavior was analyzed in terms of the capillary pressure with and without the Laplace
pressure; the theoretical and experimental results agreed moderately well. The results indicated that the Laplace pressure
cannot be neglected in the analysis. The MSD of a wet surface where a preceding micro-droplet had already landed was higher
than that on a dry or partially wet surface, presumably because water remains inside pores for an unexpectedly long time. 相似文献
110.
Towards the improvement of thermal efficiency in lignite‐fired power generation: Concerning the utilization of Polish lignite deposits in state‐of‐the‐art IGCC technology
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Yosuke Komatsu Anna Sciazko Marcin Zakrzewski Taro Akiyama Akira Hashimoto Naoki Shikazono Shozo Kaneko Shinji Kimijima Janusz S. Szmyd Yoshinori Kobayashi 《国际能源研究杂志》2016,40(13):1757-1772
Integrated coal Gasification Combined Cycle (IGCC) is the most advanced technology for coal‐fired power generation. The two‐stage entrained flow gasification process allows for the use of a wide range of coal, as long as the gasification temperature is above the ash melting point of a used fuel. In this gasification technology, lignite, which often has a low ash melting point, can be preferably utilized. However, ash fluidity is also another importance, because the behaviour of molten slag can diminish a stable ash discharge from a gasifier. As the eligibility of coal ash properties is a considerable factor, water physically and chemically kept in lignite (30 – 60% in mass) attributes to deteriorating gasification efficiency, because it causes significant heat loss and increasing oxygen consumption. Developing a thermal evaporative lignite drying method will be a necessary attempt to apply lignite to the coal gasification process. For those preceded objectives, coal and ash properties and drying characteristics of several grades of Polish lignite, extracted from Belchatow and Turow deposits, have been experimentally investigated in a preliminary study evaluating the applicability and consideration for its utilization in state‐of‐the‐art clean coal technology, IGCC. This paper particularly discusses the eligibility of Polish lignite from the perspective of the fusibility and fluidity of ash melts and the fundamental drying kinetics of lignite in superheated steam in the light of water removal. The viscosity of ash melts is measured at high temperature up to 1700 °C. In the drying tests, the significant influence of structural issues, because of the provenance and origin of lignite on the drying characteristics, was found by applying the method of sensitivity analysis of physical propensity. This paper concludes that the investigated Polish lignite has characteristics favourable for utilization in IGCC technology, once the precautions related to its high moisture have been carefully addressed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献