Applications of Xenon

Taber KH, Zimmerman JG, Yonas H, Hart W, Hurley RA. Applications of xenon CT in clinical practice detection of hidden lesions. J Neuropsychiatry Clin Neurosci 1999 ll(4) 423-5. 

At room temperature xenon is a colorless, odorless gas. Upon freezing it forms a crystal with a face-centered cnbic structure. The chief application of xenon gas is its use in various lands of lamps. In an electric discharge... 

Xenon is very useful to eharaeterize the ehannel and pore structure and numerous papers have been published on this topie in reeent years.Many of the applications of xenon NMR to zeolites have been reviewed previously, including experiments to probe issues related to porosity, crystallinity, the influence of cations, diffusivity of gases as well as eoking, and other factors causing the blocking of pores. Therefore, our treatment will be abbreviated. 

In other applications of CT, orally administered barium sulfate or a water-soluble iodinated CM is used to opacify the GI tract. Xenon, atomic number 54, exhibits similar x-ray absorption properties to those of iodine. It rapidly diffuses across the blood brain barrier after inhalation to saturate different tissues of brain as a function of its lipid solubility. In preliminary investigations (99), xenon gas inhalation prior to brain CT has provided useful information for evaluations of local cerebral blood flow and cerebral tissue abnormalities. Xenon exhibits an anesthetic effect at high concentrations but otherwise is free of physiological effects because of its nonreactive nature. 

Silyl enol ethers are fluonnated in high yields with xenon difluoride [62 93, 94 95] Applications of this reaction to the preparation of fluonnated... 

The capability to control an excimer laser beam also is exploited in the semiconductor industry, where these lasers are used to etch elaborate features during the fabrication of semiconductor chips. Neil Bartlett probably never dreamed that his explorations of the chemistry of xenon would lead to such exotic applications. 

R. W. Mair, R. Wang, M. S. Rosen, D. Candela, D. G. Cory, R. L. Walsworth 2003, (Applications of controlled-flow laser-polarized xenon gas to porous and granular media study), Magn. Reson. Imag. 21, 287. 

We have recently prepared some new and very thermolabile CO- and N2 comPlexes derived from titanocene [1] or decamethyltitanocene [2], and have characterized them by their vibrational spectra. As well as "classical" matrix spectroscopy, we have used spectroscopy in liquid xenon (LXe). The application of chemistry and methodology indicates the decamethylsilicocene structure, which represents the first example of a stable jt-complex of divalent silicon [3]. Reaction with CO or N2 leads to the two title complexes [4] ... 

The conclusions from this work were (i) that the mechanism that operates is of wide applicability, (ii) that exchange proceeds by either the dissociative chemisorption of benzene or by the dissociation of benzene which has previously been associatively chemisorbed, and (iii) that M values of about 2 indicate that further dissociation of surface-area measurements. Surface areas of metal films determined by the chemisorption of hydrogen, oxygen, carbon monoxide, or by physical adsorption of krypton or of xenon concur... 

INDUSTRIAL APPLICATION OF RUBBER SURFACE FLUORINATION WITH XENON DIFLUORIDE... 

For use in a radioactive environment the gas centrifuge must be completely maintenance free. It has been used for the separation of xenon isotopes and consideration has been given to its application for separation of fluorohydrocarbons. Worldwide, in the region of a quarter of a million gas centrifuges have been manufactured. As an order of magnitude figure, an investment of 1000 is necessary to obtain 0.3 g/s (10 g/h) of product. 

In this paper we present the first application of the ZORA (Zeroth Order Regular Approximation of the Dirac Fock equation) formalism in Ab Initio electronic structure calculations. The ZORA method, which has been tested previously in the context of Density Functional Theory, has been implemented in the GAMESS-UK package. As was shown earlier we can split off a scalar part from the two component ZORA Hamiltonian. In the present work only the one component part is considered. We introduce a separate internal basis to represent the extra matrix elements, needed for the ZORA corrections. This leads to different options for the computation of the Coulomb matrix in this internal basis. The performance of this Hamiltonian and the effect of the different Coulomb matrix alternatives is tested in calculations on the radon en xenon atoms and the AuH molecule. In the atomic cases we compare with numerical Dirac Fock and numerical ZORA methods and with non relativistic and full Dirac basis set calculations. It is shown that ZORA recovers the bulk of the relativistic effect and that ZORA and Dirac Fock perform equally well in medium size basis set calculations. For AuH we have calculated the equilibrium bond length with the non relativistic Hartree Fock and ZORA methods and compare with the Dirac Fock result and the experimental value. Again the ZORA and Dirac Fock errors are of the same order of magnitude. 

The most important application of organolithium reagents is their nucleophilic addition to carbonyl compounds. One of the simplest cases would be the reaction with the molecule CO itself, whose products are stable at room temperature. Recently, it was shown that a variety of RLi species are able to react with CO or f-BuNC in a newly developed liquid xenon (LXe) cell . LXe was used as reaction medium because it suppresses electron-transfer reactions, which are known to complicate the reaction . In this way the carbonyllithium and acyllithium compounds, as well as the corresponding isolobal isonitrile products, could be characterised by IR spectroscopy for the first time. 

Xenon dihydride is frequently observed in Xe matrices, which contain hydrogen atoms. In turn, in the context of applications of this matrix isolation technique, water is an impurity that is difficult to eliminate. For these reasons, dihydrogen... 

The application of VSEPR theory to triatomic molecules is exemplified by considering water, carbon dioxide, xenon difluoride and a trio of connected species the nitronium ion, N02+, nitrogen dioxide and the nitrite [or nitrate(III)] ion, N02. ... 

In this contribution we report an extension of a pore size - shift relationship for xenon in a number of controlled pore glasses (CPG s), and also report some applications of HP xenon spectroscopy to the study of void space in solids. 

The 021 AsF6- salt readily oxidizes molecular bromine to Br3+ ion 328. The 02+BF4 salt also reacts with xenon.873 The major application of 02+ salts is as an oxidant for collecting 222 Rn in uranium mines, since it has negligible dissociation pressure at ambient temperature and releases oxygen as a gaseous product. Reactions of the salt with radon and components of diesel exhausts (CO, C02, CH4, S02, NO, and N02) have therefore been studied in some detail.815... 

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