Search Results

You are looking at 11 - 20 of 57 items for :

  • "Synchrotron radiation" x
  • Refine by Access: All Content x
Clear All

Abstract  

In this work, elemental distributions in the rat olfactory bulbs (OB) were measured by synchrotron radiation X-ray fluorescence (SRXRF) 9 hours after unilateral intranaris application of MnCl2 solution. The effects of deposition of exogenous Mn in the OB on the distributions of other elements, particularly calcium, were also investigated. The results show that the application of MnCl2 solution in the nasal cavity resulted in inhomogeneous deposition of Mn in the OB, with the highest Mn content found in the ipsilateral glomerular layer (GL). Locations in the ipsilateral hemisphere of the OB with higher Mn content were found to be associated with significantly higher calcium and zinc contents, suggesting the presence of excess exogenous Mn may affect the homeostasis of other trace elements such as calcium and zinc.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: Jun Tang, Gengmei Xing, Hui Yuan, Xingfa Gao, Long Jing, Shukuan Wang, Yue Cheng, and Yuliang Zhao

Abstract  

The electronic properties of the metal atoms encaged in a fullerence cage were investigated using synchrotron X-ray photoelectron spectroscopy. Systematic variations in photoemission of valence band of Gd@C82, Gd@C82(OH)12, and Gd@C82(OH)22 were observed in Gd 5p levels. The results suggest that the electronic properties of the inner metal atom can be efficiently modulated by surface chemistry of the fullerene cage.

Restricted access

Summary  

This study uses fishes as indicators of metal contamination in the Piracicaba Basin and also for evaluation of the risks to human health by the ingestion of fish contaminated by metals and other potentially toxic elements. Based on total reflection X-ray fluorescence analysis, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Ba were detected and evaluated in the muscle and viscus (liver, intestine and stomach) of fish collected in the Piracicaba River.

Restricted access

Abstract  

XANES has been recently used for the determination of oxidation states of actinides in environmental samples. To obtain reliable results, however, a sufficiently long counting time at every probing energy and a large number of experimental points per XANES spectrum are required, due to the complex mathematical model used to fit the measured spectrum. This makes micro-mapping difficult, since the time required for data collection becomes unacceptably long. A simplified model for data collection and evaluation is presented. Its effectiveness has been tested by measuring the distribution of Pu oxidation states in a “hot” particle coming from a nuclear weapon test site.

Restricted access

Order-disorder transitions were investigated in native cassava starch at intermediate moisture contents (35 to 60% wt. water), using Differential Scanning Calorimetry (DSC) and dynamic Wide Angle X-ray Diffractometry (WAXS) with a synchrotron radiation source.

Restricted access

Summary  

Major and trace elements were determined in serum of patients with chronic myelogenous leukemia (CML) using total reflection X-ray fluorescence induced by synchrotron radiation (SRTXRF). CML affects 1 to 2 people per 100,000 and accounts for 7-20% cases of leukemia. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Br and Rb. Using analysis of variance (ANOVA) it was observed that the contents of the P, S, Ca, Cr, Mn, Fe, Cu and Rb elements differed significantly at a = 0.05 between groups of healthy subjects and CML patients and also genders (males and females).

Restricted access

Abstract  

The uptake of rare earth elements (REE) by Euglena gracilis cells has been investigated in Fudan University. The remarkable ability to transport REEs to these cell’s compartments had been observed. X-ray absorption fine structure experiments (XAFS) of cerium in Euglena gracilis were performed at Beijing Synchrotron Radiation Facility (BSRF) to directly determine the cerium valence state and coordination structure in situ. Extended X-ray absorption fine structure (EXAFS) derived calculation showed that cerium was surrounded by 8 N atoms with bond length of 0.258 nm. Combining with other measurements, it may indicate that most likely REEs are mainly located in chlorophyll molecules.

Restricted access

Abstract  

Mössbauer spectroscopy is a dynamic field with applications ranging from physics to biology. This paper gives a review of Mössbauer spectroscopy activities carried out by different groups in China. About thirty groups are distributed all over China for both fundamental and practical aspects. In-beam Mössbauer setup was established at HIRAC accelerator in Lanzhou, and the nuclear scattering facility has already been planned at Shanghai Synchrotron Radiation Light Source. In this review, some recent developments and achievements are discussed, as examples: (1) Brownian motion in anisotropic media, (2) applications to archaeology, and (3) molecule-based magnetic materials.

Restricted access

Abstract  

Neutron activation analysis (NAA) and synchrotron radiation X-ray fluorescence analysis (SRXRF) were used to study the loss and recuperation of inorganic elements of osteoporotic rat bone and the effects of Zhugu Capsule. The results of the animal experiments showed that there was greater loss of multiple elements in cancellous bone than in cortical bone that was difficult to be improved. Yet in the mid-shaft femur, which is mainly consisted of cortical bone, the contents of multiple elements were notably recuperated. Zhugu Capsule could increase the content of not only of Ca, but also Zn and Sr. Further, it could also improve the distribution of these elements in femur.

Restricted access