Thermal stability of water and hydroxyl on the surface of the Moon from temperature-programmed desorption measurements of lunar analog materials

Icarus ◽  
2011 ◽  
Vol 213 (1) ◽  
pp. 64-72 ◽  
Author(s):  
C.A. Hibbitts ◽  
G.A. Grieves ◽  
M.J. Poston ◽  
M.D. Dyar ◽  
A.B. Alexandrov ◽  
...  
Author(s):  
Paul M. Jones ◽  
Lei Li ◽  
Yiao-Tee Hsia

The thermal stability of Zdol 4000, 7800 and Ztetraol perfluoropolyethers (PFPE) have been studied in both the bulk with thermogravimetric analysis (TGA) and in thin film form with temperature programmed desorption spectroscopy (TPD). The TGA results have been interpreted to yield an evaporation activation energy for both Zdol 4000 (13 kcal/mole) and Zdol 7800 (19 kcal/mole). A larger activation energy is also found for all three samples investigated that is consistent with polymer decomposition (22, 27 and 21 kcal/mole respectively). The TPD threshold has been found to be approximately similar all three samples (∼500 K). The temperature of decomposition was also found to be similar for all three samples and was dominated by the CF2O+ mass fragment at ∼660 K. Two desorption maximums were observed for both Zdol 4000 and Ztetraol indicating the similarity in their decomposition chemistry. In contrast only one desorption peak was observed from Zdol 7800 (675 K). A CF3+ fragment was not observed in any of the TPD spectra indicating the absence an acidic decomposition path for all of the Fomblin Z polymers studied.


2018 ◽  
Vol 123 (9) ◽  
pp. 2445-2463 ◽  
Author(s):  
M. Formisano ◽  
C. Federico ◽  
M. C. De Sanctis ◽  
A. Frigeri ◽  
G. Magni ◽  
...  

Materials ◽  
2012 ◽  
Vol 5 (12) ◽  
pp. 327-335 ◽  
Author(s):  
Ana López Cabezas ◽  
Xianjie Liu ◽  
Qiang Chen ◽  
Shi-Li Zhang ◽  
Li-Rong Zheng ◽  
...  

2016 ◽  
Vol 2016 (0) ◽  
pp. S1320103
Author(s):  
Tsubasa YAGUCHI ◽  
Satoshi SHIBATA ◽  
Akio HAYASHI ◽  
Yohichi NAKAO

2017 ◽  
Vol 83 (856) ◽  
pp. 17-00268-17-00268 ◽  
Author(s):  
Akio HAYASHI ◽  
Yohichi NAKAO

2016 ◽  
Vol 220 ◽  
pp. 865-869 ◽  
Author(s):  
Yong Zhou ◽  
Yuan Zhong ◽  
Yinyan Gong ◽  
Xi Zhang ◽  
Zengsheng Ma ◽  
...  

1999 ◽  
Vol 564 ◽  
Author(s):  
A. Vijayendran ◽  
M. Danek

AbstractWe evaluated PECVD WNx as a potential copper barrier. Ultrathin (100 Å) PECVD WNx films were deposited utilizing WF6/N2/H2 chemistry. Films with N/W stoichiometries ranging from 0.1 to 1.0 and resistivities between 200 – 1000 μΩ-cm were deposited by varying pressure, deposition temperature, N2 flow, and H2 flow. The thermal stability of the films was evaluated by annealing Si/WNx /Cu stacks for 1 hour at temperatures up to 700°C. Barrier failure was detected by sheet resistance change and surface SIMS. The thermal stability was correlated with N/W ratio and free fluorine content as determined by temperature programmed desorption mass spectroscopy. The tests showed that films with N/W ratios between 0.3 and 0.4 had optimal barrier properties, while fluorine was seen to have a detrimental effect on barrier stability. Moreover, tests showed that the substrate affects fluorine concentration as WNx deposited on silicon dioxide has a higher interfacial fluorine content than WNx on silicon. Thus, fluorine contamination at the WNx /Si02 interface led to poor electrical reliability as measured by leakage current vs. time on MOS capacitors.


Materials ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 381
Author(s):  
Mercedes Santiago-Calvo ◽  
María Carracedo-Pérez ◽  
María Luisa Puertas ◽  
Antonio Esteban-Cubillo ◽  
Julio Santaren ◽  
...  

In the present study, a promising flame retardant consisting of 80 wt% silane-modified nanosepiolites functionalized with 20 wt% graphite (SFG) is used to obtain a synergistic effect principally focussed on the thermal stability of water-blown rigid polyurethane (RPU) foams. Density, microcellular structure, thermal stability and thermal conductivity are examined for RPU foams reinforced with different contents of SFG (0, as reference material, 2, 4 and 6 wt%). The sample with 6 wt% SFG presents a slightly thermal stability improvement, although its cellular structure is deteriorated in comparison with the reference material. Furthermore, the influence of SFG particles on chemical reactions during the foaming process is studied by FTIR spectroscopy. The information obtained from the chemical reactions and from isocyanate consumption is used to optimize the formulation of the foam with 6 wt% SFG. Additionally, in order to determine the effects of functionalization on SFG, foams containing only silane-modified nanosepiolites, only graphite, or silane-modified nanosepiolites and graphite added separately are studied here as well. In conclusion, the inclusion of SFG in RPU foams allows the best performance to be achieved.


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