Direct fluorination of polymers—From fundamental research to industrial applications

2008 ◽  
Vol 61 (2-4) ◽  
pp. 192-204 ◽  
Author(s):  
A.P. Kharitonov
2013 ◽  
Vol 34 (6) ◽  
pp. S179-S199 ◽  
Author(s):  
W Zouaghi ◽  
M D Thomson ◽  
K Rabia ◽  
R Hahn ◽  
V Blank ◽  
...  

2010 ◽  
Vol 437 ◽  
pp. 126-130
Author(s):  
Jürgen Kompenhans

Since two decades technological progress at lasers, video techniques, optoelectronics, computers and evaluation algorithms allows to extract quantitative information from images of flows, even in complex environments. Continuous improvement of such image based measurement techniques and decreasing costs of equipment enabled many research groups to exploit these techniques for extraction of 2-dimensional or even 3-dimensional data mainly for fundamental research. Since a decade ago many image based measurement techniques have found interest in aerodynamics and are even used as a matter of routine in industrial applications, especially in large wind tunnels or at in-flight testing. Application is mainly performed in the scope of large industrial projects in European co-operation. For this purpose mobile measurement systems have been developed, which can be flexibly adjusted to particular testing environments. All data is acquired non-intrusively so that no interference of the flow field by the measurement is to occur. In consequence, the methods developed are particularly suited for the aero-dynamical and aero-acoustical analysis of complex, unsteady three-dimensional flow fields. The paper will report on the state-of-the-art of the application of image based measurement techniques in aerodynamics and will describe some of the current problems and future needs.


Author(s):  
Govind Pathak ◽  
Om Prakash Dubey ◽  
Prafful Kumar Manoharan

The natural fiber-reinforced polymer composite is swiftly growing both in phrases of their industrial applications and fundamental research. They are renewable, cheap, absolutely or in part recyclable and biodegradable. The incorporation of herbal fibers consisting of sisal with glass fiber hybrid composites has additionally received growing industrial packages. Herbal and synthetic fibers are mixed in the same matrix (unsaturated polyester) to make sisal/glass fiber hybrid composites and the mechanical residences of those hybrid composites had been studied. A giant development in mechanical homes of sisal/glass fiber hybrid composites has been observed. the chalk powder (additive) is likewise introduced to the resin (unsaturated polyester) in proportions of 1%, 2%, 3% by way of weight of resin respectively and sisal/glass fiber hybrid composites were organized through the usage of this resin to take a look at the effect of chalk powder on mechanical homes of those hybrid composites. It is also found that because the chalk powder quantity increases tensile and flexural residences are decreases.


2020 ◽  
Vol 6 (6) ◽  
pp. eaay1876 ◽  
Author(s):  
Senfu Zhang ◽  
Xichao Zhang ◽  
Junwei Zhang ◽  
Arnab Ganguly ◽  
Jing Xia ◽  
...  

The direct imaging of current density vector distributions in thin films has remained a daring challenge. Here, we report that an inhomogeneous current distribution can be mapped directly by the trajectories of magnetic half-skyrmions driven by an electrical current in Pt/Co/Ta trilayer, using polar magneto-optical Kerr microscopy. The half-skyrmion carries a topological charge of 0.5 due to the presence of Dzyaloshinskii-Moriya interaction, which leads to the half-skyrmion Hall effect. The Hall angle of half-skyrmions is independent of current density and can be reduced to as small as 4° by tuning the thickness of the Co layer. The Hall angle is so small that the elongation path of half-skyrmion approximately delineates the invisible current flow as demonstrated in both a continuous film and a curved track. Our work provides a practical technique to directly map inhomogeneous current distribution even in complex geometries for both fundamental research and industrial applications.


2022 ◽  
Vol 119 (3) ◽  
pp. e2115135119
Author(s):  
Bhawakshi Punia ◽  
Srabanti Chaudhury ◽  
Anatoly B. Kolomeisky

Catalysis is a method of accelerating chemical reactions that is critically important for fundamental research as well as for industrial applications. It has been recently discovered that catalytic reactions on metal nanoparticles exhibit cooperative effects. The mechanism of these observations, however, remains not well understood. In this work, we present a theoretical investigation on possible microscopic origin of cooperative communications in nanocatalysts. In our approach, the main role is played by positively charged holes on metal surfaces. A corresponding discrete-state stochastic model for the dynamics of holes is developed and explicitly solved. It is shown that the observed spatial correlation lengths are given by the average distances migrated by the holes before they disappear, while the temporal memory is determined by their lifetimes. Our theoretical approach is able to explain the universality of cooperative communications as well as the effect of external electric fields. Theoretical predictions are in agreement with experimental observations. The proposed theoretical framework quantitatively clarifies some important aspects of the microscopic mechanisms of heterogeneous catalysis.


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