scholarly journals Light absorption and photocatalysis of flake-like titanate nanosheets chemically modified by organic ligands

2020 ◽  
Vol 128 (11) ◽  
pp. 890-897
Author(s):  
Takayuki BAN ◽  
Hiroki YAMADA ◽  
Kota IMAEDA ◽  
Tomohiro INOUE ◽  
Chika TAKAI ◽  
...  
1989 ◽  
Vol 61 (01) ◽  
pp. 131-136 ◽  
Author(s):  
Richard A Harvey ◽  
Hugh C Kim ◽  
Jonathan Pincus ◽  
Stanley Z Trooskin ◽  
Josiah N Wilcox ◽  
...  

SummaryTissue plasminogen activator labeled with radioactive iodine (125I-tPA) was immobilized on vascular prostheses chemically modified with a thin coating of water-insoluble surfactant, tridodecylmethylammonium chloride (TDM AC). Surfactant- treated Dacron, polytetrafluoroethylene (PTFE), silastic, polyethylene and polyurethane bound appreciable amounts of 125I- tPA (5-30 μg 125I-tPA/cm2). Upon exposure to human plasma, the amount of 125I-tPA bound to the surface shows an initial drop during the first hour of incubation, followed by a slower, roughly exponential release with a t½ of appoximately 75 hours. Prostheses containing bound tPA show fibrinolytic activity as measured both by lysis of clots formed in vitro, and by hydrolysis of a synthetic polypeptide substrate. Prior to incubation in plasma, tPA bound to a polymer surface has an enzymic activity similar, if not identical to that of the native enzyme in buffered solution. However, exposure to plasma causes a decrease in the fibrinolytic activity of both bound tPA and enzyme released from the surface of the polymer. These data demonstrate that surfactant-treated prostheses can bind tPA, and that these chemically modified devices can act as a slow-release drug delivery system with the potential for reducing prosthesis-induced thromboembolism.


2008 ◽  
Vol 128 (5) ◽  
pp. 732-737
Author(s):  
Hiroyuki Ichikawa ◽  
Masashi Ito ◽  
Chie Fukuda ◽  
Kotaro Hamada ◽  
Akira Yamaguchi ◽  
...  

2012 ◽  
pp. 141208072802005
Author(s):  
Fabiano Ribeiro Cirano ◽  
ADRIANE TOGASHI ◽  
MARCIA MARQUES ◽  
FRANCISCO PUSTIGLIONI ◽  
LUIZ LIMA

1995 ◽  
Vol 23 (4) ◽  
pp. 238-255 ◽  
Author(s):  
E. H. Sakai

Abstract The contact conditions of a tire with the road surface have a close relationship to various properties of the tire and are among the most important characteristics in evaluating the performance of the tire. In this research, a new measurement device was developed that allows the contact stress distribution to be quantified and visualized. The measuring principle of this device is that the light absorption at the interface between an optical prism and an evenly ground or worn rubber surface is a function of contact pressure. The light absorption can be measured at a number of points on the surface to obtain the pressure distribution. Using this device, the contact pressure distribution of a rubber disk loaded against a plate was measured. It was found that the pressure distribution was not flat but varied greatly depending upon the height and diameter of the rubber disk. The variation can be explained by a “spring” effect, a “liquid” effect, and an “edge” effect of the rubber disk. Next, the measurement and image processing techniques were applied to a loaded tire. A very high definition image was obtained that displayed the true contact area, the shape of the area, and the pressure distribution from which irregular wear was easily detected. Finally, the deformation of the contact area and changes in the pressure distribution in the tread rubber block were measured when a lateral force was applied to the loaded tire.


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