1,902 research outputs found
Self-Diffusion in Alloys
It has been successfully provided that in Fe, Co, Ni, Cu, Zn, Al, Ga, Cr, and Mn, alloy has been done to obtain reliable values of diffusion coefficient particularly with Arrhenius relationship graphic plotter tool. In the presented work, the Arrhenius plots of self-diffusions and other diffusion mechanisms have been exemplified. It is an aim to summarize diffusion coefficients in Arrhenius relations that are important for physical constant values in specified materials via free-of-charge Web-based diffusion coefficient diffusion database
MEASUREMENTS OF WINDING SPEED OF ROVING
ArticleJournal of the Faculty of Textile Science and Technology, Shinshu University. Ser. B, Engineering 14: 1-14(1979)departmental bulletin pape
Synthesis of poly(conjugated ester)s by ring-opening polymerization of cyclic hemiacetal ester bearing acryl skeleton
Available online 20 August 2019Ring-opening polymerization (ROP) of 2,6-dimethyl-5-methylene-1,3-dioxan-4-one (DMDO), a cyclic hemiacetal ester containing an acrylate skeleton, was investigated. Although the ROPs catalyzed by tin(II) 2-ethylhexanoate [Sn(Oct)(2)] and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) did not yield polymeric products, diphenyl phosphate (DPP) functioned a catalyst for the ROP through acyl scission accompanying with the elimination of acetaldehyde at 50 degrees C and 80 degrees C. The resulting polymer was a poly(conjugated ester) that had similar structure to the polymer of alpha-methylene-beta-butyrolactone (M beta BL), an alpha-exomethylene lactone with four-membered ring. Copolymerizations of epsilon-caprolactone and delta-valerolactone were also performed to yield the corresponding polyesters. The chemoselective main chain scission of the copolymers at the conjugated ester units were achieved by conjugate substitution reaction with benzyl mercaptan. Although the ROP of DMDO left a problem in the control of molecular weight, DMDO exhibited a potential as an easier accessible monomer alternative to M beta BL for the preparation of bio- and chemo-degradable polyesters.ArticleEUROPEAN POLYMER JOURNAL.120:109185(2019)journal articl
Regulation of TGF-β1-Induced Pro-Apoptotic Signaling by Growth Factor Receptors and Extracellular Matrix Receptor Integrins in the Liver
Hepatocellular carcinoma (HCC) often arises from chronically diseased livers. Persistent liver inflammation causes the accumulation of excessive extracellular matrix (ECM) proteins and impairs the liver function, finally leading to the development of HCC. A pleiotropic cytokine, transforming growth factor (TGF)-β1, plays critical roles throughout the process of fibrogenesis and hepatocarcinogenesis. In the liver, TGF-β1 inhibits the proliferation of hepatocytes and stimulates the production of ECM from hepatic stellate cells (HSCs) to maintain tissue homeostasis. During disease progression, both growth factors/cytokines and the ECM alter the TGF-β1 signals by modifying the phosphorylation of Smad proteins at their C-terminal and linker regions. TGF-β1 stimulates the expression of integrins, cellular receptors for ECM, along with an increase in ECM accumulation. The activation of integrins by the ECM modulates the response to TGF-β1 in hepatic cells, resulting in their resistance to TGF-β1-induced growth suppression in hepatocytes and the sustained production of ECM proteins in activated HSCs/myofibroblasts. Both growth factor receptors and integrins modify the expression and/or functions of the downstream effectors of TGF-β1, resulting in the escape of hepatocytes from TGF-β1-induced apoptosis. Recent studies have revealed that the alterations of Smad phosphorylation that occur as the results of the crosstalk between TGF-β1, growth factors and integrins could change the nature of TGF-β1 signals from tumor suppression to promotion. Therefore, the modification of Smad phosphorylation could be an attractive target for the prevention and/or treatment of HCC
Nonlinear analysis of composite laminated plates subjected to impact
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1992.Includes bibliographical references (leaves 177-181).by Hiroto Matsuhashi.M.S
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