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1.
Kinetics and concentration profile associated with the regulated radiodegradation of bilirubin in an organic solvent were
assessed. The pure unconjugated specimen was prepared in chloroform (40.0 μM). The depletion of bilirubin was almost linear
with dose, and complete degradation was accomplished with doses in excess of 100 Gy. The method was also evaluated for the
explicit production of the long-wavelength isomer of biliverdin, which was characterized spectrometrically by an absorbance
band in the region 600–650 nm. Results including differences in air, N2 and O2 purged samples are presented to identify the atmospheric medium for optimum production of biliverdin. The process was regulated
by controlling the dose. The general rate constant of the depletion process was estimated at a dose rate of 5.67·10−2Gy·s−1. The method is a convenient substitute for light illumination studies of bilirubin.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
S. N. Mishra D. Rambabu A. K. Grover R. G. Pillay P. N. Tandon H. G. Devare R. Vijayaraghavan 《Hyperfine Interactions》1986,28(1-4):471-474
57Fe Mössbauer and magnetization studies on a new series Fe4–2xRuxSix (1.0x1.7) are reported. The system is seen to transform from a collinear ferromagnet for x1.2 to a cluster spin glass for x>=1.54 In the intermediate region the magnetic behaviour of the system, as probed by the Mössbauer effect, is dominated by the presence of clusters and their dynamics. The alloys have large ordering temperatures ( 750 K) throughout the series except for x>1.54 where they drop sharply. The moment values, in contrast, fall sharply from 4.8B at x=1 to 0.5B at x=1.6C. The average value of the HF at57Fe measured at 15 K does not change significantly throughout the series. 相似文献
3.
A recently discovered phenomenon of excessively high X-ray production is discussed. The high yield is attributed to the build-up of potential on non-conducting targets irradiated with accelerated ion beams, and the subsequent discharge. Ion-beams of1H+,1H2
+,2H+,2H2
+,3He+,3He2+,4He+,14N+,14N2+,16O+ and20Ne+ were used. A new mechanism of X-ray excitation is proposed. The increased X-ray fluxes produced by this process are suitable for analytical applications of high specificity. The mechanism of excitation associated with the process, factors affecting the high X-ray yields, applications and a general overview of the studies undertaken with the various ion beams are given. 相似文献
4.
The feasibility is explored of classifying human hair specimens according to their trace metal composition as determined by
PIXE. Protons of 3.5 MeV were used to analyse 150 samples by energy-dispersive spectrometry using a Si(Li) detector. The methods
of the Minimal Spanning Tree and Non-Linear Mapping were used to establish correlation among the specimens. As a result of
distinct groupings obtained by these methods it was inferred that these techniques could usefully be applied to environmental
pollution studies. 相似文献
5.
Previous studies reporting abnormally high X-ray yields from the fluorides of some transition metals were extended to include a variety of other compounds. Using proton beams of 700 and 2000 keV and -beams of 1000 keV the production of abnormally high X-ray yields were critically examined for reproducibility and under different vaccum and bombarding beam conditions. 相似文献
6.
Summary We prove here:
Theorem. LetT be a countable complete superstable non -stable theory with fewer than continuum many countable models. Then there is a definable groupG with locally modular regular generics, such thatG is not connected-by-finite and any type inG
eq orthogonal to the generics has Morley rank.
Corollary. LetT be a countable complete superstable theory in which no infinite group is definable. ThenT has either at most countably many, or exactly continuum many countable models, up to isomorphism.Supported by NSF grant DMS 90-06628 相似文献
7.
M. Peisach A. E. Pillay C. A. Pineda T. Themistocleous 《Journal of Radioanalytical and Nuclear Chemistry》1992,159(1):71-76
Using 1.0 MeV protons on thick targets of zeolite pellets, aluminium and silicon were determined by PIXE. Results were compared with XRF data. The relative root mean square error was 3.7% and the results of the two methods agreed with a correlation factor of 0.991. PIXE analysis can be carried out on very small samples, while sample preparation involves minimal handling. 相似文献
8.
Annals of Operations Research - Construction heuristics play an important role in solving combinatorial optimization problems. These heuristics are usually used to create an initial solution to the... 相似文献
9.
The use of a supported phosphorus pentoxide reagent in the synthesis of selected nitriles is discussed. 相似文献
10.
A.E. Pillay 《Journal of Radioanalytical and Nuclear Chemistry》2001,250(1):181-183
Extended work, involving background effects, to confirm the charge-inducedX-ray (CHIX) phenomenon is reported. PIXE studies in pure metal targets surroundedby a special type of glass insulating material (Macor) produced higher backgrounds,in general, compared to corresponding observations made in the absence ofthe insulator. Experiments were conducted using low-energy protons of 700keV and beam currents ranging between 1–10 nA. Signal-to-noise ratiosand detection limits are compared and discussed in the light of the unusualhigh X-ray yields produced by the CHIX phenomenon. 相似文献