Wyniki wyszukiwania - Biblioteka Nauki

1

Network theory of electro-rheological fluid and its hydrodynamic characteristics in a parallel duct

100%

Shimada K. , Tateishi T. , Yamaguchi H.

International Journal of Applied Mechanics and Engineering

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2006

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tom Vol. 11, no 1

123-141

EN

We proposed a shear rheological relation based on a network theory regarding a suspension-type electro-rheological fluid (ERF) containing smectite particles. The theoretical constitutive equations concerning ERF under a D. C. electric field were derived using Rodge's network theory. The equations have creative and destructive functions expressing behavior as aggregated particles influenced by shear flow and an electric field. The theoretical results regarding viscosity based on the theoretical equations were compared with experimental data concerning the static shear stress in relation to shear rate obtained using a rotating concentric cylindrical rheometer. The viscosity behaves as a non-affine motion at a small shear rate range and as affine motion at large one. We investigated the parameters in the equations of the network theory. Next, we applied the proposed network theory to a rectangular duct ERF flow problem. The theoretical result can explain quantitatively the experimental data regarding pressure difference at a large given flow velocity. At a small given flow velocity range, the mechanical model containing the Maxwell model by Shimada can explain the experimental data quantitatively.

2

Consequences of novel technological measures on the multidirectional magnetization performance of SiFe steel

100%

Krismanic G. , Pfutzner H. , Yamaguchi H.

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tom R. 83, nr 4

35-37

EN

Silicon iron sheets represent the most traditional and common type of soft magnetic materials. Applying a 3-phase excited rotational single sheet tester, multi-directional magnetic characteristics of five different types of material were analyzed in a comparative way. In special, the paper addresses 6.5% SiFe and novel 3% SiFe products with hyper-stress coating. As a main result, and contrary to other grades, the latter novel material proves to show improved performance for both alternating and rotational magnetization.

PL

Blachy krzemowe reprezentują najczęściej używany materiał spośród stosowanych materiałów magnetycznie miękkich. Przy zastosowaniu 3-fazowefo testera strat rotacyjnych analizowano właściwości kierunkowe różnych typów blach. Szczególny nacisk położono na blachy 6.5% oraz 3% z powłoką naprężającą. W porównaniu z innymi rodzajami blach ten ostatni wykazuję szczególnie dobre właściwości, zarówno przy magnesowaniu przemiennym jak i rotacyjnym.

3

A study on possible sources of errors of loss measurement under rotational magnetization

88%

Krismanic G. , Pfutzner H. , Yamaguchi H. , Leiss E. , Chiang W.

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tom R. 83, nr 4

9-13

EN

Losses for rotational magnetization may show high variations due to complex RSST designs. This paper discusses possible error mechanisms like the influence of planar eddy currents, the arrangement of sample in the yoke, pre-stress of sample, and – in special – direction effects. The latter are attributed to (i) small deviations from target values of B due to angle errors of B-sensor components and insufficient control, and (ii) angle errors of the HB-sensor system. As a mechanism (iii), it is assumed that "hard-direction asymmetry" of the sample´s small test region - e.g. of its stress state or grain structure - may yield differences of the magnetization process with respect to domain reconstruction and thus differences of hysteresis loss and anomalous eddy current loss.

PL

Zmierzone straty rotacyjne zależą silnie od konstrukcji testera strat rotacyjnych RSST. Artykuł omawia możliwe błędy, jak na przykład wpływ powierzchniowych prądów wirowych, usytuowanie próbki, wpływ naprężeń, a szczególnie efekty kierunkowe. Te ostatnie spowodowane są (i) odchyleniem czujnika indukcji od kierunku magnesowania i (ii) błędami czujników pola magnetycznego i indukcji. Inny (iii) mechanizm wynika z asymetrii kierunku trudnego magnesowania w próbce spowodowanej naprężeniami lub wpływem struktury ziarnistej. Ta asymetria może powodować błędy określania strat histerezowych i dodatkowych.

4

Low-active high-density Noctiluca scintillans cells in surface seawater

75%

Tada K. , Asahi T. , Kitatsuji S. , Nomura M. , Yamaguchi H. , Ichimi K.

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tom 62

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nr 3

5

Effects of Clostridium perfringens enterotoxin via claudin-4 on normal human pancreatic duct epithelial cells and cancer cells

63%

Yamaguchi H. , Kojima T. , Ito T. , Kyuno D. , Kimura Y. , Imamura M. , Hirata K. , Sawada N.

Cellular and Molecular Biology Letters

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2011

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tom 16

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nr 3

EN

The tight junction protein claudin-4 is frequently overexpressed in pancreatic cancer, and is also a receptor for Clostridium perfringens enterotoxin (CPE). The cytotoxic effects of CPE are thought to be useful as a novel therapeutic tool for pancreatic cancer. However, the responses to CPE via claudin-4 remain unknown in normal human pancreatic duct epithelial (HPDE) cells. We introduced the human telomerase reverse transcriptase (hTERT) gene into HPDE cells in primary culture as a model of normal HPDE cells in vitro. hTERT-HPDE cells treated with or without 10% FBS and pancreatic cancer cell lines PANC-1, BXPC3, HPAF-II and HPAC were treated with CPE. In Western blotting, the expression of claudin-4 protein in hTERT-HPDE cells treated with 10% FBS was as high as it was in all of the pancreatic cancer cell lines. In hTERT-HPDE cells with or without 10% FBS, cytotoxicity was not observed at any concentration of CPE, whereas in all pancreatic cancer cell lines, CPE had a dose-dependent cytotoxic effect. In hTERT-HPDE cells with 10% FBS, claudin-4 was localized in the apical-most regions, where there are tight junction areas, in which in all pancreatic cancer cell lines claudin-4 was found not only in the apical-most regions but also at basolateral membranes. In hTERT-HPDE cells with 10% FBS after treatment with CPE, downregulation of barrier function and claudin-4 expression at the membranes was observed. In HPAC cells, the sensitivity to CPE was significantly decreased by knockdown of claudin-4 expression using siRNA compared to the control. These findings suggest that, in normal HPDE cells, the lack of toxicity of CPE was probably due to the localization of claudin-4, which is different from that of pancreatic cancer cells. hTERT-HPDE cells in this culture system may be a useful model of normal HPDE cells not only for physiological regulation of claudin-4 expression but also for developing safer and more effective therapeutic methods targeting claudin-4 in pancreatic cancer.