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911.
912.
The changes in the morphological structure and proteoglycan (PGs) extractability of the intramuscular connective tissues from bovine skeletal muscle exposed to high pressure (100~400 MPa) were investigated and compared to those in muscle during ageing. SDS-PAGE profiles of the PGs were also studied. During ageing, structural changes in the endomysium and perimysium occured, and disruption of the honeycomb-like structure of endomysium was observed. In the pressurized muscle, deformation of the honeycomb-like structure of endomysium was accelerated with increase of pressure applied to the muscle, and disruption of endomysium was observed in several places in the muscle pressurized at 400 MPa. Changes in the extractability of PGs were not observed in the pressurized muscle, whereas the extractability of PGs decreased with ageing. Changes in the density of the main component in the PGs with molecular mass of more than 3000 kDa on the SDS-PAGE were not observed in the PGs from the pressurized muscle, whereas the density of this band gradually decreased during the ageing. The decrease in the amounts of PGs extracted from the aged muscle seems to be due to degradation of the PGs into small dialysable molecules. From the results, it seems that high pressure treatment has some different effects on intramuscular connective tissue to ageing. ? 相似文献
913.
914.
Xiao Liang Fei Xiao Xuejun Jin Takashi Fukuda Tomoyuki Kakeshita 《Metallurgical and Materials Transactions A》2017,48(5):2105-2108
We have investigated the influence of thermal cycles on martensitic transformation of a Co2Cr(Ga,Si) ferromagnetic Heusler alloy. The as-quenched specimen exhibits successive L21(L)–D022–L21(H) martensitic transformation in the cooling process, which is known as reentrant martensitic transformation. However, heating to 800 K (527 °C) for reverse D022–L21 transformation with a rate of 10 K/min (10 °C/min) stabilizes the parent phase, meaning that the martensitic transformation is suppressed by the thermal cycles. We found precipitate after thermal cycles, and it will be the reason for the stabilization of parent phase. 相似文献
915.
Hideyuki HIRAZAWA Hiromichi AONO Takashi Naohara Tsunehiro MAEHARA Yuji WATANABE 《钢铁研究学报(英文版)》2012,(Z1):596-599
Mg1-XCuXFe2O4 type spinel ferrite was prepared by solid reaction method in order to discuss the heat generation ability in AC magnetic field.The cubic type ferrite structure was obtained for X=0-0.6 samples calcined at1200℃,and the mixture phase of cubic and tetragonal structures were obtained for X=0.7,0.8 samples from XRD result.The highest lattice parameter and highest hysteresis loss value were also shown at X=0.6 sample,the crystal distortion was increased with increase the Cu2+substitution in cubic type ferrite structure.The sized nano Mg0.4Cu0.6Fe2O4 powder was prepared by physical milling method using beads milling.The highest heat generation in the AC magnetic field was obtained for the 6 h milled samples using 0.1mm beads.The Cu2+substitution for MgFe2O4 ferrite and the beads milling were very effective for the improvement of their heat generation ability in AC magnetic field. 相似文献
916.
Yoshitaka Morimoto Hironobu Hoshino Takashi Sakurai Susumu Terakawa Akira Nagano 《Microscopy research and technique》2009,72(4):317-322
Quantitative evaluation of the ability of bone resorption activity in live osteoclast‐like cells (OCLs) has not yet been reported on. In this study, we observed the sequential morphological change of OCLs and measured the resorbing calcium phosphate (CP) area made by OCLs alone and with the addition of elcatonin utilizing incubator facilitated video‐enhanced microscopy. OCLs, which were obtained from a coculture of ddy‐mouse osteoblastic cells and bone marrow cells, were cultured on CP‐coated quartz cover slips. The CP‐free area increased constantly in the OCLs alone, whereas it did not increase after the addition of elcatonin. This study showed that analysis of the resorbed areas under the OCL body using this method enables the sequential quantitative evaluation of the bone resorption activity and the effect of several therapeutic agents on bone resorption in vitro. Microsc. Res. Tech, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
917.
918.
A novel binary porous composite nano-carbon networks (NCNs)/alumina, which is denoted as electrically conductive porous alumina (CPA), was structurally modified by carbon nanotubes (CNT) pre-treated with mixed concentrated acids at 60 °C for 6 h in this study. This conductive ceramics (CCs) was fabricated by combination of gelcasting and high temperature reductive sintering (HTRS) in novel atmosphere. CNT pre-treatment leading to the increased hydrophilicity makes it possible to make uniformly dispersed CNT/alumina slurry. And by HTRS in Ar at 1700 °C for 2 h, well-gelled polymer net-paths in green body prepared by gelcasting technology were totally converted to nano-carbon networks (NCNs) without destruction of CNT. NCN with graphitic crystal structure was evaluated by Raman spectroscopy in sintered ceramic body. Moreover, comparing with as-received CNT, the decreased surface defect of detected composite also supported the further graphitization of CNT via HTRS in Ar instead of burning out. With the aid of field-emission scanning electronic microscopy (FE-SEM) observation, the increased alumina grains in sintered ceramic body CNT/NCN/alumina was valid. Moreover, it was demonstrated that there were three components in this composite, which is carbon filler with two different forms (CNT and NCN) and alumina matrix. And these three components CNT covered with Al2O3 particles (Al2O3/CNT), NCN and alumina grains (alumina) co-exist in four different situations as follows: (a) Al2O3/CNT–alumina co-junction, (b) Al2O3/CNT–NCN co-junction, (c) Al2O3/CNT–alumina–NCN and (d) Al2O3/CNT mesh between alumina boundaries. Furthermore, by comparing with binary composite NCN/alumina (CPA), the increased flexural strength of ternary composite CNT/NCN/alumina (CNT/CPA) up to 38 MPa was attributed to the reinforcement CNT acting as elastic bridge in composite. 相似文献
919.
Asep Suhendi Muhammad Miftahul Munir Adi Bagus Suryamas Asep Bayu Dani Nandiyanto Takashi Ogi Kikuo Okuyama 《Advanced Powder Technology》2013,24(2):532-536
A new electrospray system has been successfully developed by employing a proportional–integral–derivative control action to maintain an electric current at a certain value. A polymer precursor solution containing polyethylene glycol was used to examine the performance of this system. The result showed that cone-jet geometry could be controlled easily by adjusting the electric current. The length of the cone-jet decreased as the electric current was increased, in a correlation that followed power law. We also found that the cone-jet observed during electrospraying was stable and robust with no disturbance during long periods of use (up to 4000 s). The present study is very useful for further development of high precision aerosol generators and particle synthesis. 相似文献
920.
Yuichi Yamasaki Harumi Asami Takashi Isoshima Itaru Kamiya Masahiko Hara 《Science and Technology of Advanced Materials》2013,14(6):519-522
A single chromophore detection using video-microscopy is one of the latest methodologies to reveal unique characteristics, which could not be obtained from ensemble measurements. Among many kinds of subjects, dynamic optical properties observed in colloidal semiconductor nanoparticles are attractive and important not only for the basis of photo-physics but also for application studies, e.g. biological labeling, electronic devices. In this study, fluorescence video-microscopy was performed on cadmium selenide (CdSe) quantum dots (QDs) spin-coated on a glass substrate. From single CdSe QDs detection, emissions at wavelengths separated over 60 nm were observed for the first time. This spectral feature was attributed to the existence of double-emissive relaxation processes in CdSe QDs. Photoluminescence intermittency was also observed both from relaxation processes. Fluorescence video-microscopy, which was advanced in biology, can be applicable for the real-time monitoring of dynamic properties in semiconductor photo-physics. 相似文献