PRELIMINARY STUDY OF TRACE ELEMENTS IN HUMAN BRAIN TUMOUR TISSUES BY INAA

Elemental profiles of brain tumour tissues from 15 male patients of astrocytomas (grade Ⅰ-Ⅲ) and normal human brain tissues of 23 male age matched autopsies as controls have been studied by INAA. A total of 18 elements Se, Na, K, Br, Cl, Mn, Mg. S, Ca, Cu, Hg, Cr, Fe, Rb, Zn, Co, Sc and P has been determined for this purpose. The analytical results showed that compared with the normal brain tissues, concentrations of Ca, Fe, Cu, Zn, Mn, Br and Sc were significantly higher in tumour tissues and that of Rb, K and P were lower while no differences for contents of Mg, S, Cr, Na and Cl were observed. A negative correlation between P and Ca in malignant and normal brain tissues was observed.     

Synchrotron radiation X-ray fluorescence analysis on altered mineral muscovite in gold deposit

Synchrotron radiation X-ray fluorescence (SRXRF) microprobe was used to ananlyse altered mineral muscovite and its surrounding feldspar in Yuerya gold deposit. The major, minor and trace elements of the two minerals were detected and analyzed. SRXRF analysis showed that the Yuerya muscovite had a complex chemical composition. containing K, Fe, Ca, Ti, Cr, Mn, Co, Cu, Zn and many trace or ultra-trace elements. Since muscovite resulted from the alteration of hydrothermal ore fluid acting on feldspar (plagioclase), the difference of chemical composition between the two minerals shows the components of ore fluid, which are characterized by the enrichment of alkaline and alkaline-earth metal elements K, Ca and ore-associated elements Fe, Cu, Zn. And gold. silver and platinum, invisible under microscope, were detected in some areas of muscovite but not found in feldspar. Especially platinum, a mantle material is rarely seen in the earth crust but now found in the gold deposit of magmatic sources; its appearance approves the idea of mantle flux participating in the gold mineralization, which suggests that the tectonic event controlling gold mineralization in the Yuerya district is a mantle phenomenon.     

SPM analysis on groups of single aerosol particles around steel plant

Several methods for preparing samples of dispersed single aeroslo particles used in scanning proton microprobe(SPM) analysis were tested.Many elements such as Al,Si,S,Cl,Ca,Ti,Cr,Mn,Fe,Ni,Cu and Zn in the groups of different single aerosol particles from the Capital Steel Plant area were analyzed by SPM,The distributions of elemental contents in the group of single particles were mapped with three dimensional contour and the isometric.A new approach to study the group of different single aerosol particles for air pollution is developed in the present work.The results are significant to assessing the environmental impact of the dispersed single aerosol particles.     

THE METABOLISM OF TITANIUM AND OTHER ELEMENTS IN WISTER RATS

The concentrations of Ti and Ca, P, K, Fe, Cu and Zn in blood samples were determined by PIXE after a single intravenous and a single oral dosing with titanium- ascorbate (Ti- Vc) in Wister rats. Following the intravenous injection with 50 mg Ti- Vc/kg body weight, the absorption, distribution and clearance in blood could be described by an exponential equation of three terms. After gavaged with 500 mg Ti-Vc/kg body weight, at 1.5 h the content of Ti reached the highest level. The concentration of Ca was increasing, with the absorption, distribution and clearance of Ti in blood. The contents of Fe and K were decreasing. And the contents of Cu and Zn were significantly fluctuating. The effect of Ti on animal growth could be explained by the fact that Ti- Vc supplementation could promote the absorption of Ca.     

Roadside dust contamination with toxic metals along industrial area in Islamabad,Pakistan

An investigation has been carried out to understand the contamination characteristics of roadside dust in the industrial area of Islamabad, Pakistan. The amounts of Si, S, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Pb, Zn, Ga, As, Se and Cd were determined from 95 roadside dust samples collected along the Islamabad industrial area using Proton Induced X-ray Emission （PIXE）. The results indicated that concentrations of all elements, except Cd, in the roadside dust were significant. The results of the enrichment factor show that the elementary composition of the roadside dust could be categorized as soil elements from the crust of the earth and elements from anthropogenic pollution. The high enrichment factors imply that elements such Cr, Cu, Pb, Zn, As, Se, Cd, Ni, Co and S came from anthropogenic activities. The source of metal contamination was identified using multivariate statistical analysis. It has been concluded that Ca, Sc, Ti, V, Mn and Fe mainly originate from crustal sources; Cr, Cu, Ni, Pb, Zn and Ga are associated with point-sources from industrial pollution/traffic; and S, Cl, K, As and Se are mainly related to oil/coal combustion.     

Measurement of trace element content in bone samples using long-lived neutron activation products and high-resolution gamma-ray spectrometry

A nondestructive instrumental neutron activation analysis with high-resolution gamma-ray spectrometry of long-lived radionuclides was developed and used for measurement of trace element contents in samples of bone to determine health and diseases. Using this method, the silver(Ag), cobalt(Co), chromium(Cr), iron(Fe), mercury(Hg), rubidium(Rb), antimony(Sb), selenium(Se), and zinc(Zn) mass fractions were estimated in bone samples from 27 patients with intact bone(12 females and 15 males, aged from 16 to 49 years) who had died from various non-bone-related causes, mainly unexpected traumas,and from 5 patients with chondroma(2 females and 3males, 15–42 years old), obtained from open biopsies or after operation. The reliability of the differences in the results between intact bone and bone affected by chondroma was evaluated by a parametric Student's t test and a nonparametric Mann–Whitney U test. It was found that in the bone affected by chondroma, the mean mass fractions of Co, Cr, Fe, Se, Sb, and Zn were significantly higher than in normal bone tissues. In the neoplastic bone, many correlations between trace elements found in the control group were no longer evident. This work revealed that there is asignificant disturbance of the trace element metabolism in bone affected by chondroma.     

DISTRIBUTION OF SOME ELEMENTS IN HUMAN HAIR AND ORGANS DETERMINED BY NAA

Twenty four male autopsies were obtained from Shanghai. The samples of liver, lung, kidney cortex, brain and scalp hair were collected from the autopsies. The elements As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, Mg, Mn, Na, Rb, 8, Se and Zn were determined by neutron activation analysis (NAA). The present study provides the elemental levels of different tissues for normal male adults. The distribution pattern of elements was discussed. Great difference on distribution of some elements in different tissues was observed.     

Method and portable facility for measurement of trace element concentration in prostate fluid samples using radionuclide-induced energy-dispersive X-ray fluorescent analysis

A facility and method for109 Cd radionuclide-induced energy-dispersive X-ray fluorescent(EDXRF) were developed to determine the Fe,Zn,Br,Rb,and Sr concentrations in the specimens of human prostatic fluid.Specimens of expressed prostatic fluid were obtained from 51 men(mean age 51 years,range 18–82 years) with apparently normal prostates using standard rectal massage procedure.Mean values(M ± SEL) for concentration of trace elements(mg L~(-1)) in human prostate fluid were:Fe 9.04 ±1.21,Zn 573 ± 35,Br 3.58 ± 0.59,Rb 1.10 ± 0.08,and Sr B 0.76.It was shown that the results of trace element analysis in the micro-samples(20 l L) are sufficiently representative for assessment of the Fe,Zn,Br,and Rb concentration in the prostate fluid.The facility for109 Cd radionuclide-induced EDXRF is comparatively compact and can be located in close proximity to the site of carrying out the massage procedure.The means of Zn and Rb concentration obtained for prostate fluid agree well with median of reported means.For the first time,the Fe and Br concentrations,as well as the upper limit of the Sr concentration,were determined in the human prostate fluid.     

Local structural evolutions of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis under operando conditions studied by in situ quick X-ray absorption spectroscopy

In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis. In this work, the catalyst, whose activity increases with the reaction temperature and pressure, was studied at calcined, reduced, and reacted conditions. TEM and EDX images for the calcined and reduced catalysts showed that copper was distributed uniformly at both conditions. TPR profile revealed two reduction peaks at 165 and 195 °C for copper species in the calcined catalyst. QXAFS results demonstrated that the calcined form consisted mainly of a mixed Cu O and Zn O, and it was progressively transformed into Cu metal particles and dispersed Zn O species as the reduction treatment. It was demonstrated that activation of the catalyst precursor occurred via a Cu~+intermediate, and the active catalyst predominantly consisted of metallic Cu and Zn O evenunder higher pressures. Structure of the active catalyst did not change with the temperature or pressure, indicating that the role of the Zn was mainly to improve Cu dispersion.This indicates the potential of QXAFS method in studying the structure evolutions of catalysts in methanol synthesis.     

Evaluation of sex specificity on oxidative stress induced in lungs of mice irradiated by 12C6+ions

The aim of this work is to identify if there is sex specificity on 12C6 ion-induced oxidative damage in mouse lung at different time points. Kun-Ming mice were divided into two groups, each composed of six males and six females: control group and irradiation group with a single acute dose of 4 Gy. Animals were sacrificed at 2, 4 and 12 h respectively, there lungs were removed immediately, and the oxidative stress-related biomarkers were measured by Diagnostic Reagent Kits. The results showed that the relative activities of superoxide dismutase (4 h), catalase (2 h) and Se-dependent glutathione peroxidase (12 h) have significant changes (P<0.05) between male groups and female groups, suggesting that the lungs of male mice are more sensitive to counteracting the oxidative challenge. Moreover, higher levels of malondiadehyde and lower contents of glutathione were also found in males, indicating that oxidative stress induced by 12C6 ion is pronounced in the lungs of males. We thought that these sex-responded differences may be attributed to the influence of sex hormones.     

METABOLIC KINETICS OF BRAIN MUSCARINIC CHOLINERGIC RECEPTORS IN NORMAL AND HYPOTHYROID MICE

A technique for studying in vivo the production rate and turnover rate constant of mouse brain M-receptors was established. A single injection of 25 mg / kg of Benzilylcholine Mustard to living mice resulted in 90 % irreversible block of brain M-receptors. The time course of the receptor density was then monitored by 3H-QNB binding assay and the production rate and turnover rate constant were calculated from the time course curve with a computer program. It was found that in normal mice the turnover rate constant was about 0.035 h-1 (half-life was about 20 h) and the production rate was 30-42 fmol / (h ·mg protein). Parallel experiments revealed a significant slow down of the turnover of brain M-receptors in hypothyroid mice (turnover rate constant was 0.0257±0.0012 h-1 in hypothyroid vs. 0.0356±0.0021 h-1 in normal) while the production rate was not changed significantly. The results suggest that thyroid hormones have a regulatory action on the turnover of brain M-receptors and the elevation of brain M-receptor density together with slow down of the turnover of brain M- receptors is probably one of the important mechanisms relevant to the brain dysfunction in hypothyroidism.     

The Catalytic Effect of Metal Ions on the Degradation of 4-Chlorophenol Induced by an Aqueous Pulsed Discharge Plasma

The influence of metal ions, such as Fe2+ , Fe3+ , Cu2+ and Mn2+ , on 4-CP degrada- tion was investigated in an aqueous pulsed discharge plasma system with or without the addition of a TiO 2 photo-catalyst. From an analysis of the pseudo first-order rate constant (k CP ) and energy efficiency (G 50% ) for 4-CP degradation, the experimental results show that the degradation of 4-CP is much enhanced in the presence of ferrous ions at the optimal concentration of 0.2～0.8 mmol/L or 0.2 mmol/L in an aqueous pulsed discharge plasma without or with the TiO2 system, respectively, and the enhancement is ascribed to plasma induced Fenton and photo-Fenton reactions. Meanwhile, the rank of such metal ions for catalytic effect on 4-CP degradation was Fe2+ > Fe3+ > Cu2+ > Mn2+ and Fe2+ > Fe3+ > Mn2+ > Cu2+ for the former and the latter systems, respectively, and the reasons behind this were discussed through the analysis of active species, especially hydrogen peroxide.     

Application of nuclear analytical techniques to trace elements in Cenozoic basalt and their mantle xenoliths from Aershan area in Inner Mongolia, China

Basaltic samples from different locations in Aershan area determined by instrumental neutron activation analysis (INAA) have the same distribution patterns of REE and trace elements. The similar REE contents of the same minerals without inclusions from different xenolith suggest that the mantle source region under different active volcanoes have the same composition. The REE content differences between the same minerals with and without melt inclusions selected from the same mantle xenolith indicate that the melt inclusions are rich in REE. The same patterns of trace elements of inclusions and host minerals from different xenolith analyzed by SRXRF suggest that the mantle fluid has no notable heterogeneity in Aershan area.     

GEOCHEMICAL CHARACTERISTICS OF VOLCANIC ROCKS FROM TANGBALE OPHIOLITE IN THE WESTERN JUNGGAR OF XINJIANG

An INAA technique was applied to determine simultaneously abundances of rare-earth, transitional metal, large-ion lithophile and high field strength elements in volcanic rocks from Tangbale ophiolite belt. The detailed study on trace element geochemistry shows that the volcanic rocks were erupted in the back-arc basin. The volcanic rocks of early and middle stages of the expanding period of the basin have low REE and other incompatible element contents. At early and late stages of closing period of the basin, alkalic basalts, basaltic andesites and andesites were erupted in which light REE and other incompatible elements were enriched.     

Rhenium labeled McAb—SZ39 and colloid

Two kinds of rhenium labeled radiopharmaceuticals for therapy of the human brain glioma were prepared.Anti-human brain glioma monoclonal antibody (McAb-SZ39) was directly labeled with 186 ReO4^-.When ascorbic acid was used as reduction agent of antibody and the reduction of 186 ReO4^- was finished in sodium gluconate solution(pH=2.54),the labeling efficiency was 96.2%,After purification,the labeled products were tested in respect of immunoreactivity,in vitro stability as well as inhibitory efficiency against human glioma transplanted in nude mice,188ReO4^- labeled colloid was synthesized by using a two-step method.The size of radiocolloid particles was around 2-5μm,and the radiochemical yield was over 95%,Nude mice Experiments demonstrated that the inhibitory efficiency against human brain glioma of 188Re-collied and ^188 Re-McAb-SZ39 was 90% and 65% ,respectively.     

ORIGIN OF MAGNETISM STUDY ON SOME COMMERCIAL Fe_2O_3

Six kinds of typical commercial Fe2O3 were sampled and divided into two groups A and B. according to the magnetic measurement results. The samples of group A are of susceptibility about 10-4 and the specific saturation magnetization σs 0.2-0.3 A.M2/kg, being consistent with the feature of antiferromagnetic α-Fe2O3. While the samples of group B display strong magnetism with susceptibility 10-1-10-2 and σs 1.7-12 A.M2 /kg. Mossbauer spectra of the samples were investigated at room temperature in an external magnetic field. It is suggested there is the y - Fe2O3 phase in the group B according to the relative intensities of spectra I(2,5)/I(3,4). This was proved by the Mossbauer spectra for the mixed samples A with γ-Fe2O3 at various contents and by measuring the dependence of specific saturation magnetization on temperature for the samples of group B.     

Influence of the shell effects on evaporation residue cross section of superheavy nuclei

In order to study the influence of the shell effects on the formation and fission of superheavy elements, we applied multidimensional Langevin equations. The evaporation residue cross sections have been calculated for 3n, 4n, and 5n evaporation channels using three(K = 0)-and four(K ≠ 0)-dimensional Langevin equations. Calculations were done for ~(48)Ca + ~(238)U and ~(48)Ca + ~(244)Pu hot fusion reactions with 3n, An evaporation channels and ~(70)Zn+ ~(208)Pb, and ~(54)Cr + ~(209)Bi cold fusion reactions with In and 2n evaporation channels. The calculations were performed for An and 5n evaporation channels of the ~(26)Mg+ ~(238)U reaction, as well. Our results show that with increasing dimension of Langevin equations the residue cross section increases, whereas the fission cross section decreases. The obtained results with four-dimensional Langevin and considering shell effects are in better agreement with experimental data in comparison with three-and four-dimensional Langevin equations without shell effects.     

Assessment of some chemical element contents in Traganum nudatum Del shrub using instrumental neutron activation analysis

Instrumental neutron activation analysis(INAA)has been used to determine some chemical element contents(K,Ca,Na,Fe,Zn,Co,Eu,Sb,and Sc)in Traganum nudatum Del(Chenopodiaceae family)consumed in North African rangelands by sheep livestock.Samples were collected from the area of Djelfa in an arid steppe of Algeria.Results show that pasture halophyte had sufficient levels of K,Ca,Zn,and Co to meet the requirements of ruminants.However,it seems that this halophyte shrub had substantial amounts of Na,higher than the critical level established by the National Research Council(NRC).Eu,Sb,and Sc were within the safety baseline of all the assayed elements recommended by the NRC.The high Na content(～10 g/kg)in this halophytic species requires elevated intake of water by livestock.     

Could the New Absorption Cross Section of J/psi Change the Aspect of Nuclear Absorption Mechanism

The enlarged new absorption cross section of J/psi by pion and rho mesons were put into the hadron and string cascade model, JPCIAE, and the J/psi suppression factors in p-A, O-U, S-U and Pb-Pb minimum bias collisions at 200 AGeV/c were calculated with nuclear absorption mechanism only. The results seem to indicate that, with new enlarged cross section it is still hard to change the aspect that nuclear absorption itself could not easily account for the J/psi anomalous suppression in Pb-Pb collisions.     

Surface atomic structures of Fe2O3 nanoparticles coated with cetyltrimethyl ammonium bromide and sodium dodecyl benzene sulphonate:an extended x-ray absorption fine-structure study

Fe2O3 nanoparticles coated with sodium dodecyl benzene sulphonate(DBS)or cetyltrimethyl ammonium bromide(CTAB) were prepared by using a microemulsion method in the system water/toluene.The nanoparticles were characterized by means of transmission electron microscopy and average particle sizes of 5.0nm and 6.0nm were found for DBS-modified and CTAB-modified nanoparticles respectively.The local atomic structures of these iron(Ⅲ） oxide nanoparticles were probed by using the extended x-ray absorption fine-structure technique.Fe K absorption spectra were collected at beam line 4W1B of Beijing Synchrotron Radiation Facility.A structureal model was proposed for describing their atomic structures.The Fe-O bond length at the surface of DBS-coated Fe2O3 nanoparticles was found to be similar to that in bulk Fe2O3.but there was about 0.04A expansion for the CTAB-coated Fe2O3 nanoparticles.On the basis of the model proposed in this paper,the thicknesses of the surface layers were estimated to be 0.5nm and 0.7nm.respectively,for the DBS-coated and CTAB-coated Fe2O3 nanoparticles.The anharmonicity of the atomic vibration and the asymmetry of atom-pair distribution were found to be larger at the surface of the nanoparticles than in the bulk material,while the Debye-Waller factors are almost the same for the surface and the core parts of the nanoparticles.It can be concluded that the atomic structure of the nanoparticle surface is ordered.but the atom-pari distribution is asymmetric.