Phosphorus imaging

Radioluminography (RLG) is an alternative method of radiation detection based on the phosphorus imaging technique. RLG is much more sensitive than the WBA technique, its exposure time is much shorter and it has a much wider linear measure range. Because of the latter property RLG enables a quantification of drag concentrations in whole-body sections. 

Examples of the anionic structures in polyphosphides, polyarsenides and poly antimonides. For comparison, recall the structures of red and black phosphorus and of arsenic (pp. 108, 109 and 110). Stereo image for NaPs... 

The r-delocalisation in the parent phospholide anion I (Fig. 3, R =R =H) can be expressed in the valence bond picture by resonance between the canonical structures lA-IC (and their mirror images). Phosphonio-sub-stituents (R =R =PH3 ) increase the weight of the 1,2-dipolaric canonical structure IB and induce thus, in essence, a partial r-bond localisation and a shift of r-electron density from the phosphorus to the adjacent carbon atoms [16]. Consequences of this effect are the decrease in delocalisation energy for reaction (1) depicted in Fig. 4, and lower C2-C3/C4-C5 and higher C3-C4 bond orders which are reproduced in concomitant variations of computed bond distances [16]. 

The probe species is often radioactively labeled, or it may carry a fluorescent tag, or some other chemical or enzymatic moiety to generate a positional signal. For radioactive labeling, a common choice of radioisotope is phosphorus-32 (or 32P), because it can be incorporated as phosphate into DNA or RNA relatively easily, and it emits energetic beta particles that are easy to detect. The radioactivity on the membrane can be used to expose an adjacent x-ray film in a pattern corresponding to the radioactive spots on the membrane. After a suitable exposure time, one develops the film and studies the location and intensity of the images of the radioactive spots to deduce the position and degree of probe hybridization on the membrane. 

Due to the lack of suitable standard reference material for quantification purposes in phospho-proteomics and metallomics, reliable calibration strategies were developed for the direct microlocal analysis of phosphorus and metals in protein spots and in thin sections of brain tissue using LA-ICP-MS.16,17,116 For quantification of analytical data, the application of a solution based calibration strategy was proposed with LA-ICP-MS6 and the simultaneous determination of P, S, Si, Al, Cu and Zn concentrations in human brain proteins (Alzheimer s disease) or for imaging thin... 

CHIRAL SEPARATIONS. Chiral separations are concerned with separating molecules that can exist as nnnsuperimposyhle mirror images Examples of these types of molecules, called enantiomers or optical isomers. are illustrated in Figure I. Although chirality is often associated with compounds containing a tetrahedral carbon w ith four different substituents, other atoms, such as phosphorus or sulfur, may also be chiral. In addition,... 

Yang, C., X. Sun, B. Liu, and H. Lian. 2007. Determination of total phosphorus in water sample by digital imaging colorimetry. Fenxi Huaxue 35 850-853. 

Direct proof of sidewall thiolation has been claimed recently [33], based on analyses of elemental maps in high-resolution TEM images. The authors also proposed that such sulfur functionalities replace the carboxyl and phenolic surface groups upon treatment of previously oxidized MWCNT with phosphorus pentasulfide, as follows ... 

Phosphorus compounds Mulberry moth larva Mosquito larva Image of granary weevil Tropical cockroach intact insects Tropical cockroach insects without intestines... 

When some of the ligands Lx. . . L5 are equivalent, the number of isomers of TBP phosphorus is reduced as can be seen in Table 4. Some examples of the itineraries that result by the application of both the single TR and the BPR processes are shown in Fig. 8. The descriptors for the isomers in Fig. 8 do not have a counterpart in the Binary Notations. In Fig. 8 achiral isomers fall on the symmetry axis, and chiral isomers are placed in mirror-image positions, if any. 

Hinsberger AD, Williamson PC, Carr TJ, Stanley JA, Drost DJ, et al. 1997. Magnetic resonance imaging volumetric and phosphorus 31 magnetic resonance spectroscopy measurements in schizophrenia. J Psychiatry Neurosci 22 111-117. 

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