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1.

Twenty eight stones were characterized for chemical composition and structure. The concentrations of trace elements were determined using INAA while EDXRF was used for determining the calcium contents of the stones. Twenty stones were found to be mainly composed of calcium, six were mixed type and the remaining two were of uric acid type. The concentrations of trace elements namely Zn, Sr, Fe and Cr were lower in uric acid stones as compared to calcium based stones. Diet analysis of 310 patients who were treated for renal stones showed a diet rich in calcium and oxalate and decreased water consumption.

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2.
The purpose of this study was twofold: the identification of some uranium compounds and a measurement of mixed U/Pu particles with different ratios of these elements. We used a Philips XL-30 scanning electron microscope equipped with an EDAX energy dispersive spectrometer with a Si(Li) detector and a super ultra-thin polymer window and with a Microspec wavelength dispersive spectrometer. A number of WDXRF and EDXRF spectra of U and Pu containing particles were accumulated and evaluated. The software package provided by the manufacturer was used for EDXRF spectra evaluation and calculation of the weight and atomic composition. Eight different U compounds were identified with a different degree of confidence. Several different types of U and Pu particles were measured using the WDXRF spectrometer and the results of the measurements are discussed. The measurement of mixed U-Pu particles showing large differences in the concentration of both elements can best be carried out with the use of WDXRF because the deconvolution of the M lines of U and Pu in the energy dispersive spectra is only possible over a relatively small concentration range. The results of particle analysis are very useful for verifying the absence of undeclared nuclear activities.  相似文献   

3.
We have performed spectroscopic analysis of the plasma generated by Nd:YAG laser irradiation of flesh and skin of fresh potatoes. From the spectra recorded with an Echelle spectrometer 11 minor elements have been identified. Their relative concentrations were estimated by comparing the measured spectra to the spectral radiance computed for a plasma in local thermal equilibrium. According the moderate plasma temperature of about 6500 K at the time of spectroscopic observation, the electrons are essentially generated by the ionization of the minor metal atoms, making plasma modeling possible although the organic elements may be out of equilibrium. Among the spectral lines selected for the analysis, the Na I 588.99 and 589.59 nm doublet was found to be partially self-absorbed allowing us to estimate the number density of sodium atoms. The value was found to agree with the number density predicted by the plasma model. As a result, the relative concentrations of the detected minor elements have been estimated for both the flesh and skin of the potatoes. Among these, aluminum and silicon were found to have relatively large mass fractions in the potato skin whereas their presence was not detected in the flesh. The present study shows that laser-induced breakdown spectroscopy is a promising tool to measure the elemental composition of fresh vegetables without any sample preparation.  相似文献   

4.
Summary A double focusing mass spectrometer was equipped with a laser plasma ion source. This instrument has been used for multi-element analysis of solid materials. Laser plasma mass spectrometry (LMS) permits direct analysis of both conducting and non-conducting samples. The abundances of about 30 trace elements can be determined simultaneously in rock samples. A great advantage of LMS is that most elements are ionized with about the same efficiency, this means that only small corrections are necessary for quantitative analysis. Solutions which have been dried on a quartz disk can also be analyzed. This technique yields mass spectra which are free of interferences of molecules or cluster-ions.
Spurenelementanalyse durch Laser-Plasma-Massenspektrometrie
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5.
This work describes a sampling strategy that will allow the use of portable EDXRF (energy dispersive X-ray fluorescence) instruments for "in situ" soil analysis. The methodology covers a general approach to planning field investigations for any type of environmental studies and it was applied for a soil characterization study in the zone of Campana, Argentina, by evaluating data coming from an EDXRF spectrometer with a radioisotope excitation source. Simulating non-treated sampled as "in situ" samples and a soil characterization for Campana area was intended. "In situ" EDXRF methodology is a powerful analytical modality with the advantage of providing data immediately, allowing a fast general screening of the soil composition.  相似文献   

6.
A method for simultaneous determination of Cr, Fe, Co, Ni, Cu, Zn, As e Pb in liquid chemical waste using Energy Dispersive X-Ray Fluorescence (EDXRF) technique was evaluated. A small sample amount (200 μL) was dried on a 6.35 μm thickness Mylar film at 60 °C and the analyses were carried out using an EDXRF spectrometer operated with an X-ray Mo tube (Zr filter) at 30 kV/20 mA. The acquisition time was 300 s and the Ga element was utilized as internal standard at 25 mg/L for quantitative analysis. The method trueness was assessed by spiking and the detection limit for those elements ranged from 0.39 to 1.7 mg/L. This method is notable because it assists the choice of the more appropriated waste treatment procedure, in which inter elemental interference is a matter of importance. In addition, this inexpensive method allows a non-destructive determination of the elements from 19K to 92U simultaneously.  相似文献   

7.
Drinking water is the essential medium for food production, and is also needed for direct consumption; while it must be free of harmful substances, it also must have a composition that is beneficial to health. The aim of this study was to evaluate the influence of water and wastewater treatment on reducing the concentrations of zinc (Zn), nickel (Ni), iron (Fe), manganese (Mn), copper (Cu), lead (Pb), and arsenic (As) in the Western Pomerania Voivodeship in Poland. The research was carried out in 2017–2019. The analysis was performed with inductively coupled plasma atomic emission spectrophotometry (ICP-AES). The concentrations of trace elements in drinking water were below maximum acceptable concentrations (MACs). Reductions in the most dangerous elements during water treatment fluctuated from 48.5% (As) to 97% (Pb). Wastewater treatment reduced the concentrations of analyzed elements by a range of 28.6 to 60.8%, and the most toxic elements (Pb and As) by over 50%. Trace element concentrations in treated wastewater were below MAC values, and ranged from 1.15% (Pb) to 6.23% (As) of MACs for toxic elements. The concentrations of both essential elements (Zn, Ni, Fe, Mn, Cu) and toxic elements (Pb, As) in drinking water were below the MACs. Water treatment had a significant (p < 0.05) effect on decreasing trace element concentrations.  相似文献   

8.
Summary Several analytical conditions and detection limits of various metal elements were examined with regard to the determination of these elements by photoelectric spectrometry in the combination of high-frequency plasma torch apparatus and Ebert-type grating spectrometer (GE-340), using nitrogen as the carrier gas. All the calibration curves for the elements showed good linearity and standard deviations of calcium, zinc, tin, lead, and bismuth were in the range of 1.0–3.2%. It was found that, among the various elements, aluminium, zinc, tungsten, and lead, which are difficult to be determined by flame-spectrometric analysis, can be determined with good sensitivity and high precision by the present method.
Zusammenfassung Zur spektrometrischen Bestimmung verschiedener Metalle wird eine Kombination von hochfrequenter Plasmaflamme und Gitterspektrometer vom Ebert-Typ (GE-340) benutzt, wobei Stickstoff als Trägergas dient. Alle Eichkurven weisen eine gute Linearität auf; die Standardabweichungen für Ca, Zn, Sn, Pb und Bi liegen im Bereich von 1,0 bis 3,2%. Al, Zn, W und Pb, deren Bestimmung nach der flammenspektrometrischen Methode Schwierigkeiten bereitet, können mit Hilfe des beschriebenen Verfahrens mit guter Empfindlichkeit und hoher Genauigkeit bestimmt werden.


Dedicated to Prof. Dr. H.Kaiser on his 60th birthday.  相似文献   

9.
Nowadays there are many sun-protection cosmetics incorporating chemical and/or physical UV filters as active ingredients and there are no official methods to determine these kinds of compounds in sunscreen cosmetics. The objective of this work is to estimate TiO2 concentration, without sample preparation, employing a portable energy dispersive X-ray fluorescence (EDXRF), aiming to estimate the sun protection factor (SPF) due to the physical barrier in sunscreen composition, and also identify the metals present in the samples. A portable EDXRF system was used for the analysis of fifteen commercial samples. It was also prepared three formulations estimated in FPS-30 using TiO2 at 5%. Quantification was performed using calibration curves with standards from 1 to 30%. The physical barrier contribution in the SPF, associated to Ti concentration, was determined for all samples. The presence of some elements, like K, Zn, Br and Sr was detected in the sunscreen, identifying chemical elements that were not cited in the formulations. Three commercial samples were analyzed for total SPF determination and the result shows that the measured value is 10% lower than the nominal one.  相似文献   

10.
能量色散X荧光光谱仪至今还没有形成统一的国家检定规程.因此,根据仪器的实际检定要求,参考相关仪器的检定规程,对能量色散X荧光光谱仪的检定方法进行了深入的研究和探讨,提出了能量色散X射线荧光光谱仪的检定方法.  相似文献   

11.
Sample volatilisation of copper-base alloys in a hot-type hollow cathode (HC) is studied. The intensity vs time curves for lead, zinc, tin and copper during the excitation of brass and bronze were measured with the aid of a vidicon spectrometer. The homogeneity of sparked-off samples was studied with the aid of electron-probe microanalysts, and their composition was determined by inductively coupled plasma—atomic emission spectral analysis. The results provide information about the optimum discharge conditions for the determination of volatile elements in less volatile matrices with the aid of a hot HC.  相似文献   

12.
13.
Energy dispersive X-ray fluorescence spectroscopy (EDXRF) has been used for elemental analysis of Cu−Ni alloy, neodymium aluminide, and iron and nickel powder. The preparation of Cu−Ni alloy and neodymium aluminide has been carried out by aluminothermic reduction of mixed oxides of copper and nickel and neodymium oxide respectively. Aqueous electrorefining technique has been followed for the preparation of iron and nickel powder using Fe−Ni alloy as anode. The determination of major and trace elements present in the Cu−Ni and, electrolytically refined nickel and iron has been accomplished by EDXRF using Cd109 radioisotope source. In the case of Nd−Al alloy Am241 radioisotope source has been used. The rapid and multielement analysis of the thermit product by EDXRF has aided in the appropriate variation of the charge constituents during the standardization of the optimum charge composition for Cu−Ni alloy. EDXRF analysis of electrolytically refined nickel and iron revealed heavy contamination of iron in nickel as compared to that of nickel in iron. Neodymium content has been found to be 67.68% in Nd−Al alloy.  相似文献   

14.
Trace elements play an important role in the human central nervous system. Significant variations of the concentration of trace elements in body fluids may occur in neurodegenerative diseases. In the present work an investigation of the elemental composition of the serum, and the cerebrospinal fluid in amyotrophic lateral sclerosis patients and a control group was performed.For the analysis of the body fluids Total reflection X-ray Fluorescence (TXRF) spectrometry was used. The samples were taken during routine diagnostic procedures. Na, Mg, Cl, K, Ca, Cu, Zn, and Br were determined in both fluids. In order to validate the results of analysis a serum standard reference material was measured. A t-test was applied to check if the mean concentrations of the elements are different for ALS and the control group. For the serum samples higher values for Br were found in the ALS group, for the cerebrospinal fluid lower values of Na, Mg and Zn as well as higher Ca values were found in the ALS group compared to the control group.  相似文献   

15.
Kidney stones obtained from six patients belonging to the stone belt region of India (Punjab) were analyzed for inorganic constituents using instrumental neutron activation analysis (INAA) and energy dispersive X-ray fluorescence (EDXRF) techniques. For INAA, samples were irradiated along with IAEA RM Soil 7 as reference standard in CIRUS reactor, BARC, Mumbai. Gamma activity of irradiated samples was measured using a 45% relative efficiency HPGe detector coupled to 8?k channel analyzer. EDXRF method was used for determination of concentration of Ca. The concentrations of ten elements namely Ca, Na, K, Mn, Co, Cr, Zn, Br, Sm and Cl, are reported and discussed.  相似文献   

16.
《Analytical letters》2012,45(13):2476-2484
Abstract

The application of energy dispersive X‐ray fluorescent analysis (EDXRF) for the determination of elements released from five different dental luting cements such as Zinc Polycarboxylate (Carbchem), Zinc carboxylate (Adhesor Carbofine), Glass ionomer (Meron), Resin cement (Duo‐cement kit), and Carboxylate (Durelon) in artificial saliva is described. The equipment used for this study is a Si(Li) detector, a multichanel analyser, an amplifier and 55Fe and 241Am radioisotope sources. The physical basis of the analytical method used the procedure of sample preparation and results are presented. The detected elements were Cl, P, K, Ca. The results show high concentrations of Ca being released from dental cements in artificial saliva. Chemical disintegration of dental cements can adversely affect their long‐term performance. Fixed prosthodontic restorations cemented with carboxylate cement (Durelon) may be capable of withstanding long‐term clinical use compared to other agents. This material showed the highest resistance to dissolution or disintegration.  相似文献   

17.
Energy-dispersive X-ray fluorescence spectrometer (EDXRF) with primary radiation monochromatized by LiF(200) crystal was developed. In the constructed spectrometer, the radiation from the Ag target X-ray tube operated at 50 kV and 40 mA excites the secondary target (Cu, Se, Zr or Mo). The characteristic radiation (Cu Kα, Se Kα, Zr Kα or Mo Kα) of the target is monochromatized with LiF(200) crystal and excites elements in the analyzed sample. The X-ray spectra are collected by thermoelectrically cooled Si-PIN detector with resolution of 145 eV at 5.9 keV. The pinhole collimator placed in front of the X-ray detector allows reducing size of the analyzed area. Quantitative analysis is performed using standardless fundamental parameters (FP) method. Because sample is excited using highly monochromatized radiation, the calculations are much simpler and analysis error resulting from uncertainty of X-ray tube spectral distribution is completely eliminated. Moreover, EDXRF system allows obtaining very low background and appropriate secondary target can be selected for the best excitation of the determined elements and to avoid overlapping of the analyte peaks with characteristic radiation originating from the secondary target. The FP calculations were verified using several certified reference materials of stainless steel. The spectrometer was used for nondestructive analysis of mono- and polycrystals of selenide spinels of general formula MxNyCrzSe4 (where M, N are Cu2+, Zn2+, Cd2+, Mn2+, Ge2+, Ni2+, V3+, Sb3+, Ga3+). The results from EDXRF were compared with those obtained by means of the wavelength-dispersive X-ray fluorescence spectrometry (WDXRF).  相似文献   

18.
This work is an attempt to evaluate the possible influence of the mother's age in trace element concentrations in human amniotic fluid and placenta and whether these concentrations are correlated to the weight of the newborn infants. Total-reflection X-ray fluorescence (TXRF) was used to analyze 16 amniotic fluid samples, and the placenta samples were analyzed by energy dispersive X-ray fluorescence (EDXRF). The whole samples were collected during delivery from healthy mothers and healthy infants and full-term pregnancies. According to the age of the mother, three different groups were considered: 20–25, 25–30 and 30–40 years old. Only two mothers were aged more than 35 years. The weight of the infants ranged from 2.56 to 4.05 kg and three groups were also considered: 2.5–3, 3–3.5 and 3.5–4 kg. The organic matrix of the amniotic fluid samples was removed by treatment with HNO3 followed by oxygen plasma ashing. Yttrium was used as the internal standard for TXRF analysis. Placenta samples were lyophilized and analyzed by EDXRF without any chemical treatment. Very low levels of Ni and Sr were found in the amniotic fluid samples, and were independent of the age of the mother and weight of the child. Cr, Mn, Se and Pb were at the level of the detection limit. Zn, considered one of the key elements in neonatal health, was not significantly different in the samples analyzed; however, it was weakly related to birth weigh. The concentrations obtained ranged from 0.11 to 0.92 mg/l and 30 to 65 μg/g in amniotic fluid and placenta, respectively. The only two elements which seemed to be significantly correlated with mother's age and newborn weight were Ca and Fe for both types of sample: Ca levels were increased in heavier children and older mothers; however, Fe increased with increasing maternal age, but decreased for heavier babies. The same conclusions were obtained for placenta and amniotic fluid samples. Cu is closely associated with Fe in its function in the organism and has a similar behavior to this element, but not as pronounced.  相似文献   

19.
Among all environmental pollutants, particulate matter (PM) poses the major threat to our health. These tiny airborne particles vary in shape and composition, which is reflected in their hazardous potential. The particles are small enough to penetrate deep into the lungs and even enter the bloodstream, causing severe diseases. Therefore, their regular monitoring is required. Toxic metals and other elements are often measured by regulatory agencies as well as in research laboratories, either to compare ambient concentrations with prescribed limit values or to study provenance of air pollution sources in order to target PM pollution mitigation strategies. The most established method for the determination of regulated Pb, Cd, As, Ni and other elements in PM is microwave digestion inductively coupled plasma mass spectrometry (MW/ICPMS), whereas X-ray fluorescence (XRF) techniques have also often been used, especially in research. In this review paper we critically assess these two and three other analytical techniques (i.e., LA-ICPMS, PIXE and INAA) for element determination in PM deposited on filter media. All aspects from sample treatment to measurement range and limitations, costs and waste management are considered. In conclusion we identify XRF and LA-ICPMS as two promising surface techniques for the analysis of a PM deposit on a filter, which could replace the laborious wet MW/ICPMS method, which is – considering its wide use, very incriminating to the environment. In short, EDXRF is the cheapest, simplest for use and already customized for PM samples, whereas LA-ICPMS is promising, but still needs some development in the direction of autosamplers and matrix-matched standards for calibration.  相似文献   

20.
《Analytical letters》2012,45(13):2107-2121
The elemental composition of four wild edible mushroom species was determined by inductively coupled plasma optical emission spectrometry (ICP OES): scotch bonnet (Marasmius oreades), chanterelle (Cantarellus cibarius), porcini (Boletus edulis), and peppery milk-cap (Lactarius piperatus). Mushrooms are a potassium-rich food, which was confirmed in this study. M. oreades contained the highest concentration of almost all elements, except for cadmium, potassium, phosphorus, and lead. Lead and cadmium were present but at concentrations that are not hazardous to human health. A principal component analysis loading plot for elemental composition demonstrated that 95.51 percent of the total variance was present in the first two principal components. Cluster analysis separated the elements into three statistical significant clusters.  相似文献   

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