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1.
Matching and analysis of dissimilar images of a given scene gathered from different sources are important processes for their integration (e. g. in the course of a multisource interpretation or quantification). However, prior to the analysis, geometric distortions caused by the acquisition process have to be eliminated. This problem involves two steps: the extraction of dominant image features (control structures), such as edges or regions with homogeneous elemental coverage and the estimation of the model parameters of the geometric transformation based on the calculated features. An approach for a 5-parameter automatic matching process for data from SAM (Scanning Auger Microscopy), SIMS (Secondary Ion Mass Spectroscopy) or EPMA (Eletron Probe Micron Analysis) multispectral images is presented. The parameters include global translation, rotation and scaling.  相似文献   

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A global collaboration is currently developing solvent extraction separations for the nuclear fuel cycle of the future. The goal is to recover fissionable material for recycle, mitigate proliferation concerns, and mitigate the environmental impact of nuclear waste disposal. Relying on selective metal complexing agents, the radiation stability of these solvent extraction ligands will determine the efficiency and recycle lifetime of any solvent intended for use in this high-radiation environment. This paper reviews work at the Idaho National Laboratory regarding the radiation chemistry of nuclear solvent extraction ligands, with particular emphasis on the reactions of nitrogen-centered radicals.  相似文献   

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A precise and economic way for quantitative bulk analysis of silicon/aluminium, oxygen and nitrogen in the technological important silicon- and aluminium oxynitride thin films based on FT-IR and EPMA is presented and the use of data gained by the latter method is discussed for the calculation of relative sensitivity factors for SIMS and hf-SNMS. Advantages and disadvantages of SIMS, hf-SNMS and hf-GD-OES were compared. The combination FT-IR/EPMA/SIMS offers at present the best possibility for a quantitative bulk and in-depth distribution analysis of such films in the range of 20 to 1000 nm thickness. Alternatively for thicker films, combinations of FT-IR/EPMA/hf-SNMS or FT-IR/EPMA/hf-GD-OES are easier to apply but their use is restricted to oxygen concentrations higher than 10 wt%.  相似文献   

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Summary Possibilities of the measurement of elemental maps and their digital processing are demonstrated. Hardware and software developments and some applications for various material problems are discusses.  相似文献   

7.
Vesuvianite, a complex sorosilicate, often contains variable (from trace-to-minor-element) amounts of H, B and F. We describe a microanalytical study of H, B and F in vesuvianite by means of Electron Probe Microanalysis (EPMA), Secondary Ion Mass Spectrometry (SIMS), and single-crystal Fourier-Transform InfraRed (FTIR) spectroscopy. Most crystals investigated are B- (up to 3.67 wt% B2O3) and F-rich (up to 2.38 wt%); H2O ranges from 0.243 to 0.665 wt%. The H data obtained by SIMS allowed us to calibrate the quantitative analysis of H2O by FTIR spectroscopy. The resulting molar absorption coefficient (ɛ i = 100 000 ± 2000 L · mol−1 · cm−2) is in excellent agreement with working curves available from the literature. Moreover, the SIMS data allowed us to obtain the calibration curve to estimate the B2O3 content on the basis on the FTIR absorbance: a i = 34000 ± 1400 · B2O3 (wt%).  相似文献   

8.
 A solar control coating was analysed by different methods of surface analysis with respect to the layer sequence and the composition and thickness of each sublayer. The methods used for depth profiling were Auger electron spectroscopy, electron probe microanalysis, secondary neutral mass spectroscopy and secondary ion mass spectroscopy based on MCs+. The structure of the coating was unknown at first. All methods found a system of two metallic Ag layers, embedded between dielectric SnOX layers. Additionally, thin Ni-Cr layers of 1–2 nm were detected on top of the Ag layers. Thus the detected layer sequence is SnOX/Ni-Cr/Ag/SnOX/Ni-Cr/Ag/SnOX/glass. The Ni:Cr ratio in the nm-thin layers could be quantified by every method, the Cr fraction corresponding to less than one monolayer. We compare the capabilities and limitations of each method in routinely investigating this solar control coating. Importance was attached to an effective investigation. Nevertheless, by combining all methods, measuring artefacts could be uncovered and a comprehensive characterisation of the system was obtained.  相似文献   

9.
The behaviour of gases produced by fission is of great importance for nuclear fuel operation. Within this context, an experimental method for the characterisation of the fission gas including gas bubbles in an irradiated UO2 nuclear fuel was developed in our laboratory using SIMS, EPMA and SEM results. SIMS and EPMA have been used to measure the radial distribution of xenon and SEM gives information on bubble formation across the fuel pellet radius. Using SIMS, xenon concentration can be determined in the matrix and in the bubbles. A quantification method, allowing the determination of the total inventory of xenon, is proposed and qualified with EPMA results. It is concluded that the complementary micro-analytical techniques SIMS, EPMA and SEM are very powerful tools for the characterisation of the fission gas bubbles in irradiated nuclear fuel.  相似文献   

10.
Willich  Peter  Wang  Min  Wittmaack  Klaus 《Mikrochimica acta》1994,114(1):525-532
Several analytical techniques have been used to characterize homogeneous films of tungsten-containing hydrogenated carbon (W-C: H), deposited on Si with a film thickness of 1–1.5 m. Electron probe microanalysis (EPMA) enables one to determine the major components W (3–43 at %) and C, impurities (< 2 at %) of Ar and O, and the mass thickness (300–1800 g/cm2) of the films. The agreement between the results of EPMA and the data (W-content, mass thickness) provided by Rutherford backscattering spectrometry (RBS) is 5–10% relative. Quantitative analysis of hydrogen in W-C:H films (1–16 at %) is carried out by the technique of elastic recoil detection (ERD). A suitable scheme for the determination of H in W-C: H films by SIMS is proposed, based on monitoring the intensity ratio of HCs+/CCs+ secondary ions.  相似文献   

11.
A combination of chemical analysis, EPMA, SIMS, and TEM was applied to gain information on the bulk values, the microstructure and the microdistribution of contaminants. The limitations of classical chemical analysis were overcome by the application of highly sophisticated analytical techniques. Optimized measurement conditions were worked out for SIMS analysis and basic data such as relative sensitivity factors were gained for further investigations. A correlation between the microdistribution of contaminants and mechanical data could not be established so far, since only two samples were investigated.List of acronyms used BAS British Association of Standardisation (UK) - CGHE carrier gas hot extraction - DL detection limit - ED energy discrimination - EPMA electron probe micro analysis - E 0 energy of primary ions - HMR high mass resolution - I B primary ion beam current - NBS National Bureau of Standards (USA) - OES optical emission spectroscopy - PI primary ions - RSF relative sensitivity factor - SI secondary ions - SIMS secondary ion mass spectrometry - SKF SKF Analytica Taeby (Sweden) - TEM transmission electron microscopy - XRFA X-ray fluorescence analysis - d A diameter of analyzed area  相似文献   

12.
Aomori Prefectural Govemment and Japan Nuclear Fuel Limited started environmental radiation monitoring around Nuclear Fuel Cycle Facilities in April 1989. External radiation is measured by NaI(TI) scintillator and Themoluminescence dosimeter. The level of external radiation is relatively low in the winter due to snow. We have collected terrestrial samples of drinking water, soil, agricultural products and marine samples of seawater, sea sediment, seafood, etc. periodically. We have measured many radionuclides and fluoride in these samples. In soil sample,239+240Pu ratio to137Cs was almost constant at all sampling points. A correlation was observed between salinity and concentration of tritium, uranium and fluoride in lake water of Lake Obuchinuma. The correlation between137Cs and239+240Pu in lake sediment was observed in each lake.  相似文献   

13.
Manganese dioxide (MnO2) appears to be an effective cathode material for a battery system. No studies on lithium insertion in aqueous media are known to the best of our knowledge. However, in one of our previous papers we reported that lithium could be intercalated into a MnO2 host compound using an aqueous LiOH electrolyte; however simple chemistry suggests that it should not. It is found that a battery with LiOH electrolyte functions quite differently from the cell that uses Li2SO4. This paper describes the surface modifications that accompany the electrochemical behavior of MnO2 during redox (discharge) processes in the lithium hydroxide and sulfate media. XPS and SIMS techniques were used to study the resultant surface of the MnO2 cathode and the spectra reveal that the formation of an insoluble layer of Li2CO3 precedes the process of reduction. SEM was used to study the microstructure of the MnO2 cathode. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

14.
Chemical interactions at the phase boundaries of materials applied for the solid oxide fuel cell (SOFC) have been studied by EPMA. The chemical reactivity at the interface of La(y-x)Sr(x)MnO(3)/ZrO(2)-Y(2)O(3) is dependent on the stoichiometry (y) and the Sr content (x) of the perovskite. Typical reaction products (zirconates) and a diffusion zone in the ZrO(2)-Y(2)O(3) have been observed. The extension of cation release (Mn) is related to the increasing chemical activity of Mn oxide in the perovskite by the Sr substitution for La. The wettability of the metal/oxide interface in the anode cermet (Ni/ZrO(2)-Y(2)O(3)) has been found to be influenced by chemical reactions resulting from the applied reducing atmosphere with high carbon activity. The disintegration of ZrO(2)-Y(2)O(3) in contact with molten Ni or Ni-Ti and Ni-Cr alloys leads to the redeposition of Y(2)O(3)-enriched oxides and also to Zr-rich intermetallic compounds and eutectics.  相似文献   

15.
Lacquer has been used in Asian countries for thousands of years as a natural coating material owing to its durable, adhesive, decorative, and protective properties. Protection and restoration of lacquer‐coated cultural remains has become an important subject, and identification of the lacquer types in old lacquer‐wares has also become very important for conservation and restoration research. This paper provides identification of several molecular species of vegetal‐source Asian lacquers with the aim of providing a methodology for application in the field of cultural heritage. Several chemical markers of the vegetal species in Asian lacquers were identified using a methodology consistent with the sampling restrictions required for cultural‐heritage objects. Surface analytical methods such as time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy were used to characterize Korean, Chinese, and Vietnamese lacquers; avoiding time‐consuming and destructive extraction processes. These ToF‐SIMS results provided the structural characterization of a series of catechol derivatives. The ToF‐SIMS spectra of Rhus vernicifera from Korea and China, and Rhus succedanea from Vietnam indicated a series of urushiol and laccol repeat units, respectively, in the mass range of m/z 0–1800. Because of its sensitivity, specificity, and speed of analysis, the ToF‐SIMS technique can be used to investigate cultural lacquer‐coated treasures as well as to discriminate among different Asian lacquer coatings or binding mediums for the conservation or restoration of lacquer‐ware. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

16.
Ion exchange distribution coefficients of zirconium, ruthenium, europium, and strontium, elements found in high level nuclear waste, were determined for a new titanium hydrous oxide-type inorganic ion exchange compound. Coefficients were determined at ambient temperatures and at 85°C. The equilibrations were done in solutions simulating the composition of nuclear waste expected from the Allied-General Nuclear services, Barnwell. South Carolina plant. The progress of each reaction was monitored by adding a radiotracer of the element investigated to the simulated waste solution. Ambient temperature distribution coefficients ranging from a high of 1.2·106 for Zr to a low of 58 for Eu were obtained when equal weights of ion exchange material were used. Significantly higher distribution coefficients were found at 85°C than at ambient temperatures. This work was supported by the U. S. Energy Research Development Administration.  相似文献   

17.
Non-metallic impurities or phases are often unintentional but important constituents in steel – they primarily influence the properties and behavior of the material by forming crystallization nuclei during the solidification process of the molten material. The kind, formation and spatial distribution of these inclusions has been investigated in this work by 2D SIMS, depth profiling and scanning SIMS. These non-metallic phases can be divided into oxides, nitrides, carbides, sulfides and gas bubbles. Probably the most important phase, the oxygenic, results from reactions of the molten bath with the ambient air and from the admixture of de-oxidation components. The investigated HSS specimen exhibits two different classes of inclusions. The first class mainly contains sulfide precipitates and differs widely from the second. The latter exhibits a spherical structure with the outer sphere combining the oxygenic precipitation and the core containing nitrides and sulfides. Due to the small size of the inclusions, they have been investigated by high resolution scanning SIMS to separate the different phases. Received: 30 July 1997 / Revised: 9 February 1998 / Accepted: 15 February 1998  相似文献   

18.
Recently published results of the cooperative studies executed by the Institute of Physical Chemistry and Electrochemistry of Russian Academy of Sciences (IPCE RAS), Research Center Vallée du Rhone (CEA, France), Institute of Nuclear Physics Orsay and University Bordeaux I [Centre Nationale de Recherches Scientifiques (CNRS), France] are reviewed. The review includes data obtained for the first time on the electrochemical properties and anodic dissolution of uranium monocarbide considered among possible bases of the fuel for the reactors of the IVth generation. The results of the investigations in the field of the synthesis of tetraalkyl ammonium pertechnetates, their physicochemical properties and thermal decomposition with formation of Tc metal and Tc monocarbide are summarized. The electrochemical reactions with participation of Tc ions in various oxidation states and their application in the nuclear fuel cycle are described. The behavior of technetium in natural waters near the locations of the radwastes long-term storage and in the areas surrounding nuclear power plants in RF and France was studied.  相似文献   

19.
Secondary ion mass spectra recorded on sputtering individual particles of occupational dust emitted by nuclear plants carry information about the chemical composition of the microsamples. Along with the data of isotopic analysis, the data of secondary ion mass spectrometry enables one to judge the function of the materials and the character of processes occurred at the plant. The efficiency of the procedure is demonstrated by the results of analyses of real samples selected by inspectors of the International Atomic Energy Agency at plants with nuclear fuel cycle  相似文献   

20.
The feasibility of identifying spent nuclear fuel arising from an unknown fuel cycle in terms of reactor type and burnup using a database of nuclide composition vectors generated for combinations of these two variables is examined. The database and test cases were generated using ORIGEN-ARP, and the concentrations of 200 nuclides were analyzed for each sample. Nearest neighbors and ridge regression techniques were used to make predictions of the reactor type and burnup of test cases. Various truncated nuclide lists were also tested. An initial examination of the techniques’ sensitivity to measurement error was made by perturbing the unknowns’ composition vector and examining the effect on each of the technique’s predictions. We demonstrate through the results of these experiments that investigation and development of multivariate data analysis methodologies for nuclear forensics applications is warranted.  相似文献   

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