ADSORPTION AND DECOMPOSITION OF NICKEL CARBONYL ON THE SURFACE OF RESPIRATOR CHARCOALS

1948 ◽  
Vol 26b (7) ◽  
pp. 541-549
Author(s):  
H. Leverne Williams

Nickel carbonyl is adsorbed by respirator charcoals without decomposition in the absence of oxygen. The amount adsorbed is reduced if the charcoal has previously adsorbed nickel carbonyl, carbon tetrachloride, phosgene, or arsine and has not been degassed thereafter. The adsorbed nickel carbonyl is oxidized rapidly by oxygen, liberating carbon dioxide, carbon monoxide, and leaving an amorphous deposit on the charcoal. This deposit is slightly more than half nickel, and does not yield an X-ray diffraction pattern. Adsorbed nickel carbonyl is decomposed thermally to give metallic nickel and carbon monoxide. The nickel is deposited in sufficient amounts to give an X-ray diffraction pattern.

2014 ◽  
Vol 13 (05n06) ◽  
pp. 1460001
Author(s):  
Yanxi Tan ◽  
Ying Zhang ◽  
Jian Zhang ◽  
Yanjun Zheng

Presented here is a water-stable MOF material [ In (5- AIPA )2] ⋅ Me 2 NH 2(1; 5-AIPA = 5-Aminoisophthalic acid) built from the connecting of tetrahedral building units [ In ( COO )4]-. The sql net of compound 1 exhibits preferable chemical and thermal stability confirmed by thermal gravimetric analyses (TGA) and powder X-ray diffraction pattern (PXRD) measurements. The activated empty phase of 1a, as a good candidate material for CO 2 capture, shows a CO 2 uptake of 56.6 cm3/g and CH 4/ CO 2 selectivity in excess of 16.4. Remarkably, based on the cation exchange mechanism, 1a has excellent MB affinity and can adsorb MB over MO from water in two hours. The results further support the idea that the ionic MOFs can find more applications in the separation of ionic dyes for the purifying of dye wastewater.


Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.


Author(s):  
Daniel C. Pease

A previous study demonstrated that tissue could be successfully infiltrated with 50% glutaraldehyde, and then subsequently polymerized with urea to create an embedment which retained cytomembrane lipids in sectioned material. As a result, the 180-190 Å periodicity characteristic of fresh, mammalian myelin was preserved in sections, as was a brilliant birefringence, and the capacity to bind OsO4 vapor in the hydrophobic bilayers. An associated (unpublished) study, carried out in co-operation with Drs. C.K. Akers and D.F. Parsons, demonstrated that the high concentration of glutaraldehyde (and urea) did not significantly alter the X-ray diffraction pattern of aldehyde-fixed, myelin. Thus, by itself, 50% glutaraldehyde has little effect upon cytomembrane systems and can be used with confidence for the first stages of dehydration.


2019 ◽  
Author(s):  
Kam Sang Kwok ◽  
Yuxuan Wang ◽  
Michael Cao ◽  
Hao Shen ◽  
Weinan Xu ◽  
...  

<p>The local structure and geometry of catalytic interfaces can influence the selectivity of chemical reactions. Here, using a pre-strained polymer, we uniaxially compress a thin gold film to form a nano-folded catalyst. We observe two kinds of folds and can tune the ratio of loose to tight folds by varying the extent of pre-strain in the polymer. We characterize the nano-folded catalysts using x-ray diffraction, scanning, and transmission electron microscopy. We observe grain reorientation and coarsening in the nano-folded gold catalysts. Electroreduction of carbon dioxide with these nano-folded catalysts reveals an enhancement of Faradaic efficiency for carbon monoxide formation by a factor of about four. This result suggests that electrolyte mass transport limitations and an increase of the local pH in the tight folds of the catalyst outweigh the effects of alterations in grain characteristics. Together, our studies demonstrate that nano-folded geometries can significantly alter grain characteristics, mass transport, and catalytic selectivity. </p>


2019 ◽  
Vol 15 ◽  
pp. 102605
Author(s):  
Ian Gregory Shuttleworth

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. K. Eseev ◽  
A. A. Goshev ◽  
K. A. Makarova ◽  
D. N. Makarov

AbstractIt is well known that the scattering of ultrashort pulses (USPs) of an electromagnetic field in the X-ray frequency range can be used in diffraction analysis. When such USPs are scattered by various polyatomic objects, a diffraction pattern appears from which the structure of the object can be determined. Today, there is a technical possibility of creating powerful USP sources and the analysis of the scattering spectra of such pulses is a high-precision instrument for studying the structure of matter. As a rule, such scattering occurs at a frequency close to the carrier frequency of the incident USP. In this work, it is shown that for high-power USPs, where the magnetic component of USPs cannot be neglected, scattering at the second harmonic appears. The scattering of USPs by the second harmonic has a characteristic diffraction pattern which can be used to judge the structure of the scattering object; combining the scattering spectra at the first and second harmonics therefore greatly enhances the diffraction analysis of matter. Scattering spectra at the first and second harmonics are shown for various polyatomic objects: examples considered are 2D and 3D materials such as graphene, carbon nanotubes, and hybrid structures consisting of nanotubes. The theory developed in this work can be applied to various multivolume objects and is quite simple for X-ray structural analysis, because it is based on analytical expressions.


2020 ◽  
Vol 7 (21) ◽  
pp. 4197-4221 ◽  
Author(s):  
Francisco Colmenero ◽  
Jakub Plášil ◽  
Jiří Sejkora

The structure, hydrogen bonding, X-ray diffraction pattern and mechanical properties of six important uranyl carbonate minerals, roubaultite, fontanite, sharpite, widenmannite, grimselite and čejkaite, are determined using first principles methods.


1995 ◽  
Vol 80 (7-8) ◽  
pp. 869-872 ◽  
Author(s):  
George D. Guthrie ◽  
David L. Bish ◽  
Robert C. Reynolds

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