Sulfur probe

Sulfur probe An ionization probe coated with a thin layer of molten sulfur on its conducting tip is used for measurement of shock velocity (Figure 3.18b). This is a special probe which is used in the conducting medium (Sulfur is non-conducting at ambient pressure but becomes conducting at shock pressures as its resistance decreases drastically at such pressures). This property of sulfur allows the R-C network to generate an electrical pulse at the time of arrival of shock wave. 

Although x-rays probe inner rather than valence electrons, in light elements the chemical state of the emitting atom may affect inner-shell energies enough to be detected at high resolution. Thus the K d lines of sulfur at 0.537 nm shift by 0.3 pm between the oxidation states and. ... 

Schwefel-natrium, -natron, n. sodium sulfide, -nickel, m. nickel sulfide, -niederschlag, m. precipitate of sulfur, precipitated sulfur, -ofen, m. sulfur burner, -oxyd, n. (any) sulfur oxide, -phosphor, m. (any) phosphorus sulfide, -probe, /. sulfur sample mercury sulfide, -quelle, /. sulfur spring, -rducherung, /. sulfur fumigation, -rubin, m. ruby sulfur, realgar, -salz, n. sulfur salt, thio salt, sulfo salt sulfate. 

X-ray absorption near edge structure (XANES) spectroscopy is a non-destructive and sensitive probe of the coordination number and geometry as well as of the effective charge of a chosen atom within a molecule and therefore also of the formal oxidation number. Recently, there have been a number of XANES studies at the sulfur K-edge demonstrating the sensitivity of... 

Shaw, C.F. Ill, Schaeffer, N.A., Elder, R.C., Eidsness, M.K., Trooster, J.M. and Calls, G.H.M. (1984) Bovine serum albumin-gold thiomalate complex gold-197 Moessbauer, EXAFS and XANES, electrophoresis, sulfur-35 radiotracer, and fluorescent probe competition studies. Journal of the American Chemical Society, 106, 3511-3521. 

The detector is based on the combustion of sulfur-containing compounds in a hydrogen rich air fleuie of a FID to form sulfur monoxide. The hydrogen/air flow rate ratio is the most critical parameter controlling the production of sulfur monoxide. Under optimum conditions sulfur monoxide may account for up to 20% of the sulfur species in the flame. Sulfur monoxide is a free radical and a very reactive species that is short lived however, it can be stabilized in a vacuum, and a ceramic probe under reduced pressure can be used to sample it in the flame and transfer it to... 

It is of interest to examine the development of the analytical toolbox for rubber deformulation over the last two decades and the role of emerging technologies (Table 2.9). Bayer technology (1981) for the qualitative and quantitative analysis of rubbers and elastomers consisted of a multitechnique approach comprising extraction (Soxhlet, DIN 53 553), wet chemistry (colour reactions, photometry), electrochemistry (polarography, conductometry), various forms of chromatography (PC, GC, off-line PyGC, TLC), spectroscopy (UV, IR, off-line PylR), and microscopy (OM, SEM, TEM, fluorescence) [10]. Reported applications concerned the identification of plasticisers, fatty acids, stabilisers, antioxidants, vulcanisation accelerators, free/total/bound sulfur, minerals and CB. Monsanto (1983) used direct-probe MS for in situ quantitative analysis of additives and rubber and made use of 31P NMR [69]. 

Raman spectroscopy is a useful probe for detecting transannular S - S interactions in bicyclic or cage S-N molecules or ions. The strongly Raman active vibrations occur at frequencies in the range 180-300 cm-1, and for S- -S distances in the range 2.4-2.7 A. On the basis of symmetry considerations, the Raman spectrum of the mixed sulfur-selenium nitride S2Se2N4 was assigned to the 1,5- rather than the 1,3- isomer.37... 

The oxidizing power of the catalytic sulfite ion/02 systems was utilized in oxidative cleavage of DNA (118-121), in an analytical application for the determination of sulfur dioxide in air (122) and in developing a luminescent probe for measuring oxygen uptake (123). 

Absorption spectra, 23 3 of fats and oils, 10 822-823 of polymethine dyes, 20 506-512 Absorption spectroscopy, infrared reflection, 24 114-116 Absorption towers, in sulfuric acid manufacture, 23 779 Absorptive probes, 11 150 ABS polymers, 10 205-207. See also ABS (acrylonitrile-butadiene-styrene) materials... 

The site responsible for CH30 formation can be identified with the use of CO as a probe molecule. As increasing amounts of sulfur are added to Ni(100), the desorption state characteristic of CO on the clean surface disappears, and two new states appear at 315 and 380 K, respectively. These states persist from about 0g - 0.15 to 0gO. 46 (see Figure 5). In this coverage range one sulfur atom blocks adsorption of one CO molecule (15). 

Sulfur dioxide was the major volatile product and was used as a probe to correlate the radiation resistance with polymer structure. The use of biphenol in the polymer reduced G(SO ) by 60% compared with bisphenol A based systems (Bis-A PSF). Surprisingly, the isopro-pylidene group was shown to be remarkably radiation resistant. The ultimate tensile strain decreased with dose for all polysulfones investigated and the rate of decrease correlated well with the order of radiation resistance determined from volatile product measurements. The fracture toughness (K ) of Bis-A PSF also decreased with irradiation dose, but the biphenol based system maintained its original ductility. 

In most cases, introduction of fluorine adjacent to sulfur can be monitored by proton NMR for small-scale probe reactions run in CDCI3. The CHF peaks in the... 

The Dp and Dq are the diffusion coefficients of probe and quencher, respectively, N is the number molecules per millimole, andp is a factor that is related to the probability of each collision causing quenching and to the radius of interaction of probe and quencher. A more detailed treatment of fluorescence quenching including multiexponential intensity decays and static quenching is given elsewhere/635 There are many known collisional quenchers (analytes) which alter the fluorescence intensity and decay time. These include O2/19 2( 29 64 66) halides,(67 69) chlorinated hydrocarbons/705 iodide/715 bromate/725 xenon/735 acrylamide/745 succinimide/755 sulfur dioxide/765 and halothane/775 to name a few. 

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