Certified Reference Material

Consistency of δ 13 C measurements can be improved 39-47% by anchoring the δ 13 C scale with two isotopic reference materials differing substantially in 13 C/ 12 C. It is recommended that δ 13 C values of both organic and inorganic materials be measured and expressed relative to VPDB (Vienna Peedee belemnite) on a scale normalized by assigning consensus values of -46.6‰ to L-SVEC lithium carbonate and +1.95‰ to NBS 19 calcium carbonate. Uncertainties of other reference material values on this scale are improved by factors up to two or more, and the values of some have been notably shifted: the δ 13 C of NBS 22 oil is -30.03‰. Differences in measured isotope amount ratios of stable carbon isotopes ( 13 C/ 12 C), commonly called δ 13 C values, are used in oceanography, atmospheric sciences, biology, paleoclimatology, geology, environmental sciences, food and drug authentication, and forensic applications. Progress in these fields requires smaller measurement uncertainties to be achieved. Advances require more accurate and intercomparable measurements; for example, a difference of 0.01‰ in δ 13 C of global atmospheric CO 2 can equate to a global carbon balance source/sink discrepancy of ∼400 Tg among international monitoring networks. 1 Although advances in instrumentation enable increasingly precise measurements, laboratories measuring the same specimen often disagree by 10 times their reported "uncertainty" of measurement, 2,3 and agreement has not improved appreciably in the last two decades, except in special cases.

Cancer is a life threatening disease. Many people die of cancer every year. Epidemiological studies suggest that alteration of trace elements in the body can contribute to the development of cancer. The aim of this study was to determine the concentration of zinc (Zn), copper (Cu), lead (Pb), Nickel (Ni), iron (Fe) and magnesium (Mg) in the blood, hair and nails of lymphoma and esophageal cancer (EC) patients in Khyber Pakhtunkhwa. The results reveal that the mean concentration of Cu, Pb and Ni increased significantly, while the concentration of Zn, Fe and Mg significantly decreased in the blood, hair and nails of lymphoma and EC patients. From this study it can be concluded that increased Pb, Cu, Ni and decreased Zn, Fe and Mg concentration in lymphoma and esophageal cancer patients suggest that these may play some role in carcinogenesis.

In this work, the possibilities for the direct determination of Cr in solid samples by means of graphite furnace atomic absorption spectrometry (SS-GFAAS) and by means of electrothermal vaporization-inductively coupled plasma mass spectrometry (SS-ETV-ICPMS) have been critically evaluated and compared, the goal always being to develop simple and fast methods, only relying on the use of aqueous standards for calibration. Four reference materials of very different nature (milk powder, lobster hepatopancreas, polyethylene and sewage sludge), covering a wide Cr concentration range (from 17.7 ng g 21 to 37.2 mg g 21 ), were selected for the study. The diverse volatility of their matrixes, compared with that of Cr, resulted in different degrees of difficulty for both techniques. SS-GFAAS offers a better limit of detection (2 ng g 21 ) than SS-ETV-ICPMS (30 ng g 21 ), mainly due to the occurrence of C-based polyatomic interferences with the latter technique. The samples that presented the least difficulties were those for which the matrix is mainly of an organic nature and can be easily removed during the pyrolysis step, allowing a selective atomization/vaporization of the analyte. Under these circumstances, external calibration against aqueous standards was feasible for SS-GFAAS in all cases. SS-ETV-ICPMS proved to be more sensitive to matrix effects, but the use of the palladium (added for its carrier properties) signal as internal standard also allowed the use of this straightforward calibration procedure. On the other hand, the analysis of sewage sludge (containing 85% of hardly volatile inorganic compounds) represented the most complicated situation for both techniques: for SS-GFAAS, the addition of Na 2 CO 3 to effect an in-situ microfusion of the sample during the pyrolysis step greatly helped to improve the situation, while for SS-ETV-ICPMS the single standard addition method was necessary. In all cases, a good agreement with the certified values was obtained. The precision ranged between 6 and 22% relative standard deviation, depending on the homogeneity and the sample mass used. These values could be further improved, if needed, by increasing the number of replicates per determination (usually five). Every determination required approximately 15-20 min, except when the single standard addition method was used (30-40 min). Therefore, it can be stated that both techniques show the capability of providing a direct determination of this analyte in a variety of samples, at very different concentration levels, allowing the development of fast and reliable solid sampling procedures.

. Therefore, the Re-Os system can be applied widely to derive constraints on many geological processes and environmental issues related to sedimentary rocks (e.g., . Siliceous sediments and sedimentary rocks are commonly used for investigations of surface processes and material transportation, specifically in relation to environmental problems. However, the abundances of Os in those materials are usually no more than a few tens of parts per trillion (

Page 1. Traceability for measurements of radioactivity in waste materials arising from nuclear site decommissioning This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2007 Metrologia 44 S140 ...

Held in Krakow from 8-10 June 2010, the 2 nd MoniQA International Conference was an inter-and cross-disciplinary event, which formed a bridge between the daily concerns of citizens, economic considerations and food and nutrition science. In nine technical sessions the conference set out the state-of-the-art concerning food safety standards, mycotoxins and phycotoxins, food allergens, chemical contaminants, microbiological contaminants, food additives, emerging technologies for food safety assessment and food authenticity.

The quality control (QC) and performance evaluation for the k 0 -based neutron activation analysis (k 0 -NAA) at the Portuguese research reactor (RPI) has been developed with the intention of using the method to meet the demands of trace element analysis for the applications in environmental, epidemiological and nutritional studies amongst others. The QC and performance evaluation include the following aspects: (1) estimation of the overall/combined standard uncertainty from the primary uncertainty sources; (2) validation of the method using a synthetic multi-element standard (SMELS); and (3) analysis of the certified reference materials from the National Institute of Standards and Technology (USA): NIST-SRM-1633a and NIST-SRM-1648 and the reference material from the International Atomic Energy Agency: IAEA-RM-336, for the purpose of controlling the overall accuracy and precision of the analytical results. The obtained results revealed that the k 0 -NAA method established at the RPI was fit for the purpose. The overall/ combined standard uncertainty was estimated for elements of interest in the intended applications. The laboratory's analytical results as compared to the assigned values with the bias were less than 12% for most elements, except for a few elements which biased within 13-18%. The u-score values for most elements were less than 91.649, except for Co, La and Ti within 91.649-91.969 and Sc, Cr, K and Sb within 91.969-92.589. The NIST-1633a was also analyzed over 14 months for the purpose of evaluating the reproducibility of the method. The quality factors of k 0 -NAA established at RPI were evaluated, proving that the method meets the requirements of trace element analysis, which is also considering the method's performance for which the k 0 -NAA affords a specific, rapid and convenient capability for the intended applications.

This work reports on x-ray absorption spectroscopy study at the Si K edge of several amorphous SiO x C y H z polymers prepared by plasma-enhanced chemical-vapor deposition with different C / O ratios. SiO 2 and SiC have been used as reference materials. The comparison of the experimental Si K-edge x-ray absorption nearedge structure spectra with theoretical computations based on multiple scattering theory has allowed us to monitor the modification of the local coordination around Si as a function of the overall C / O ratio in this kind of materials.

Scapolites are pervasive rock-forming aluminosilicates that are found in metamorphic, igneous, and hydrothermal environments; nonetheless, the stability field of Cl-rich scapolite is not well constrained. This experimental study investigated two reactions involving Cl-rich scapolite. First, the anhydrous reaction 1 of plagioclase + halite + calcite to form scapolite [modeled as: 3 plagioclase (Ab 80 An 20 ) + 0.8 NaCl + 0.2 CaCO 3 = scapolite (Ma 80 Me 20 )] was investigated to determine the effect of the Ca-rich meionite (Me = Ca 4 Al 6 Si 6 O 24 CO 3 ) component on the Na end-member marialite (Ma = Na 4 Al 3 Si 9 O 24 Cl). Second, the effect of water on this reaction was investigated using the hydrothermally equivalent reaction 2, H 2 O + scapolite (Ma 80 Me 20 ) = 3 plagioclase (Ab 80 An 20 ) + CaCO 3 + liquid, where the liquid is assumed to be a saline-rich hydrous-silicate melt. Experiments were conducted with synthetic phases over the range of 500-1030 °C and 0.4-2.0 GPa. For reaction 1, intermediate composition scapolite shows a wide thermal stability and is stable relative to plagioclase + halite + calcite at temperatures above 750 °C at 0.4 GPa and 760 °C at 2.0 GPa. For reaction 2, intermediate scapolite appears to be quite tolerant of water; it forms at a minimum bulk salinity [X NaCl = molar ratio of NaCl/(NaCl+H 2 O)] of the brine of approximately 0.2 X NaCl at 830 and 680 °C at pressures of 2.0 and 1.5 GPa, respectively. Based on the study done by Almeida and Jenkins (2017), pure marialite is very intolerant of water when compared to intermediate composition scapolite. Compositional changes in the scapolite and plagioclase were characterized by X-ray diffraction and electron microprobe analysis and found to shift from the nominal bulk compositions to the observed compositions of Ma 85 Me 15 for scapolite and to Ab 91 An 09 for plagioclase. These results were used to model the phase equilibria along the marialitemeionite join in temperature-composition space. This study demonstrates that a small change in the scapolite composition from end-member marialite to Ma 85 Me 15 expands the stability field of marialite significantly, presumably due to the high entropy of mixing in scapolite, as well as increases its tolerance to water. This supports the much more common presence of intermediate scapolites in hydrothermal settings than either end-member meionite or marialite as is widely reported in the literature.

The dynamics of blood and hemolymph sedimentation is studied in real time using the photoacoustic technique. A modified configuration of a conventional photoacoustic cell is used, where the advantage of this methodology is that the sample is not illuminated directly and that the process can be monitored through the measurement of the thermal contact between a reference material and the blood. It is demonstrated that during the process the thermal effusivity decreases at the region of contact between the sample and the reference materials. The usefulness of these results in real time monitoring using photothermal techniques is discussed.

We present new analytical data of major and trace elements for the geological MPI‐DING glasses KL2‐G, ML3B‐G, StHs6/80‐G, GOR128‐G, GOR132‐G, BM90/21‐G, T1‐G, and ATHO‐G. Different analytical methods were used to obtain a large spectrum of major and trace element data, in particular, EPMA, SIMS, LA‐ICPMS, and isotope dilution by TIMS and ICPMS. Altogether, more than 60 qualified geochemical laboratories worldwide contributed to the analyses, allowing us to present new reference and information values and their uncertainties (at 95% confidence level) for up to 74 elements. We complied with the recommendations for the certification of geological reference materials by the International Association of Geoanalysts (IAG). The reference values were derived from the results of 16 independent techniques, including definitive (isotope dilution) and comparative bulk (e.g., INAA, ICPMS, SSMS) and microanalytical (e.g., LA‐ICPMS, SIMS, EPMA) methods. Agreement between two or more independent me...

Environmental context. Arsenic can be found in all environmental compartments in a large number of chemical forms of varying toxicity. We performed an inter-laboratory comparison study focusing on quantitation of some of the most toxic arsenic forms in seven different biological materials and found very good agreement among the submitted results. Certification of the studied materials will provide suitable quality control samples for environmentally relevant concentrations of arsenic in food products and biota.

This supplementary material describes in detail: the emission spectrum of Bi EDL (Fig. ); dependence of peak area on the flow rate of inner Ar shield I and outer Ar shield II in FIGS (Fig. ); and table with the results of the interference study (Table ).

The contamination of the marine environment surrounding coastal Antarctic research stations remains insufficiently understood in terms of its extent, persistence, and characteristics. We investigated the presence of contaminants in marine sediments near Casey Station, located in the Windmill Islands of East Antarctica, during the period spanning from 1997 to 2015. Metals, hydrocarbons, PBDEs, PCBs, and nutrients were measured in sediments at anthropogenically disturbed sites, including the wastewater outfall, the wharf area, two former waste disposal sites, and various control locations. Sampling was carried out at three spatial scales: Locations, which were generally kilometres apart and formed the primary scale for comparison; Sites, which were 100 meters apart within each location; and Plots, which were 10 meters apart within each site. Consistently higher concentrations of most contaminants, and in some cases nutrients, were observed at disturbed locations. Some locations also exhibited an increase in contaminant concentrations over time. The spatial distribution of sediment properties (such as grain size and organic matter) and contaminants displayed intricate patterns of variation. Variation in grain size depended on the size category, with fine grains (e.g., <63 μm) showing the greatest variation at the Location scale, while coarse grains exhibited minimal variation at this scale. Contaminant levels demonstrated significant differences between Locations, accounting for approximately 55% of the overall variation for metals, while the variation within the 10-meter scale generally exceeded that within the 100-meter scale. Residual variation among replicate samples was also very high, demonstrating the need for adequate replication in studies of sediments and contaminants around stations. Some contaminants exceeded international guidelines for sediment quality, including metals, hydrocarbons, and PCBs. We conclude that Antarctic research stations such as Casey are likely to pose a moderate level of long-term ecological risk to local marine ecosystems through marine pollution. However, contamination is expected to be confined to areas in close proximity to the stations, although its extent and concentration are anticipated to increase with time. Raising awareness of the contamination

Here we present the Synthetic Gene Database (SGDB): a relational database that houses sequences and associated experimental information on synthetic (artificially engineered) genes from all peerreviewed studies published to date. At present, the database comprises information from more than 200 published experiments. This resource not only provides reference material to guide experimentalists in designing new genes that improve protein expression, but also offers a dataset for analysis by bioinformaticians who seek to test ideas regarding the underlying factors that influence gene expression. The SGDB was built under MySQL database management system. We also offer an XML schema for standardized data description of synthetic genes. Users can access the database at . evolvingcode.net/codon/sgdb/index.php, or batch downloads all information through XML files. Moreover, users may visually compare the coding sequences of a synthetic gene and its natural counterpart with an integrated web tool at , and discuss questions, findings and related information on an associated e-forum at . evolvingcode.net/forum/viewforum.php?f¼27.

A novel hydrophobic sorbent material for on-line column preconcentration and separation systems coupled with atomic spectrometry was developed. Poly(etheretherketone) (PEEK) in the form of turnings was used as packing material and evaluated for trace lead determination in environmental samples. Sample and ammonium diethyl-dithiophosphate (DDPA) reagent were mixed on-line and the Pb(II)-DDPA complex was retained effectively on PEEK-turnings. Isobutyl methyl ketone (IBMK) was adopted for efficient analyte complex elution and subsequently transportation into the nebulizer-burner system for atomization. The developed sorbent material has shown, excellent chemical and mechanical resistance, fast adsorption kinetics permitting the use of high sample flow rates without significant loss of retention efficiency. For 120 s sample preconcentration time the sampling frequency was 20 h -1 , the enhancement factor was 110, the detection limit (3 s) was c L = 0.32 g L -1 , and the relative standard deviation (RSD) was s R = 2.2%, at the 50.0 g L -1 Pb(II) level. The accuracy of the developed method was evaluated by analyzing certified reference materials.

A novel automatic sequential injection (SI) single-drop micro-extraction (SDME) system is proposed as versatile approach for on-line metal preconcentration and/or separation. Coupled to electrothermal atomic absorption spectrometry (ETAAS) the potentials of this SI scheme are demonstrated for trace cadmium determination in water samples. A non-charged complex of cadmium with ammonium diethyldithiophosphate (DDPA) was produced and extracted on-line into a 60 L micro-drop of di-isobutyl ketone (DIBK). The extraction procedure was performed into a newly designed flow-through extraction cell coupled on a sequential injection manifold. As the complex Cd(II)-DDPA flowed continuously around the micro-droplet, the analyte was extracting into the solvent micro-drop. All the critical parameters were optimized and offered good performance characteristics and high preconcentration ratios. For 600 s microextraction time, the enhancement factor was 10 and the sampling frequency was 6 h -1 . The detection limit was 0.01 g L -1 and the precision (RSD at 0.1 g L -1 of cadmium) was 3.9%. The proposed method was evaluated by analyzing certified reference material.

This paper presents the results of an intercomparison exercise for the determination of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in PM 10 , which are regulated by the European Directives for ambient air quality. Thirteen laboratories participated, generally using the European reference methods of measurement which consist of a microwave digestion followed by analysis with either ICP-MS or GFAAS. Each participant was asked to analyse five test samples: a liquid Certified Reference Material (CRM), two sub-samples of a NIST dust CRM (one already-digested and one to be digested by the participants) and two loaded filters (one already-digested and one to be digested by the participants). Participants were able to meet the Data Quality Objectives (DQOs) of the European Directives (expanded uncertainties of 25% for Pb and 40% for As, Cd and Ni) for 93% of all test samples, except for the loaded filter that were digested by the participants. In fact, only 76% of DQOs were met for this test sample, the closest to a routine sample analysis in the laboratory. The difficulties in analysing this test sample came mainly from digestion and contamination processes. Satisfactory results were also obtained using other digestion techniques (Soxhlet extraction and high pressure methods) and analytical methods (ICP-OES for Cd, Ni and Pb, EDXRF for Pb and Ni and Voltammetry for As, Ni, and Pb). Participants claimed uncertainties of about 10% for Pb and between 15 and 20% for As, Cd and Ni. These uncertainties were confirmed for 77% of results. The reproducibility of the methods of measurement was between 41 and 54% while repeatability remained between 5 and 12% except for the analysis of As on filters which was up to 20%. The majority of participant results showed higher between-day variability (14 AE 11%) than within-day variability (6.0 AE 5.3%).

The main challenge of Embrapa is to develop a model of genuine Brazilian tropical agriculture and livestock. To get this task, the quality of laboratories results is mandatory, increasing the demand for reference materials. Projects were proposed to produce reference materials to support the national agriculture laboratories and consolidate a network able to perform reliable and reproducible analytical testing laboratory within the internationally standards required. Reference materials were produced and available to interested laboratories and collaborative tests were conducted to obtain consensus values. The results and statistical evaluations were performed with the use of software developed by Embrapa Pecuária Sudeste.

In Nederland zijn de bodems van oude binnensteden (ophooglagen) in het verleden gevormd door stadsafval en puin, onder andere afkomstig van industriele activiteiten. Dit materiaal is vaak verontreinigd met lood, en zo ook de bodems. Vooral kinderen zijn gevoelig voor de schadelijke effecten van lood als zij dat via de mond binnenkrijgen. Een te hoge blootstelling aan lood kan de ontwikkeling van de hersens verstoren. Er bestaan meerdere laboratoriummodellen die schatten hoeveel lood uit de bodem in het maag-darmkanaal vrijkomt en vervolgens bij kinderen in het bloed kan terechtkomen (biobeschikbaarheid). Het RIVM heeft onderzocht hoe goed drie van deze modellen deze schatting kunnen maken. Hieruit blijkt dat al deze methoden sterke en zwakke punten hebben, maar dat het zogeheten Unified BARGE Model het meest geschikt is om biobeschikbaarheid van lood in ophooglagen te schatten. Met de drie modellen is de biobeschikbaarheid van lood in zes bodems geschat. De uitkomsten zijn vervolgen...

We present osmium isotopic results obtained by sequential leaching of the Murchison meteorite, which reveal the existence of very large internal anomalies of nucleosynthetic origin (ε 184 Os from -108 to 460; ε 186 Os from -14.1 to 12.6; ε 188 Os from -2.6 to 1.6; ε 190 Os from -1.7 to 1.1). Despite these large variations, the isotopic composition of the total leachable osmium (weighted average of the leachates) is close to that of bulk chondrites. This is consistent with efficient largescale mixing of Os isotopic anomalies in the protosolar nebula. The Os isotopic anomalies are correlated, and can be explained by the variable contributions of components derived from the s, r and p-processes of nucleosynthesis. Surprisingly, much of the s-process rich osmium is released by relatively mild leaching, suggesting the existence of an easily leachable s-process rich presolar phase, or alternatively, of a chemically resistant r-process rich phase. Taken together with previous evidence for a highly insoluble s-process rich carrier, such as SiC, these results argue for the presence of several presolar phases with anomalous nucleosynthetic compositions in the Murchison meteorite. The s-process composition of Os released by mild leaching diverges slightly from that released by aggressive digestion techniques, perhaps suggesting that the presolar phases attacked by these differing procedures condensed in different stellar environments. The correlation between ε 190 Os and ε 188 Os can be used to constrain the s-process 190 Os/ 188 Os ratio to be 1.275±0.043. Such a ratio can be reproduced in a nuclear reaction network for a MACS value for 190 Os of ~200 ± 22 mbarn at 30 keV. More generally, these results can help refine predictions of the s-process in the Os mass region, which can be used in turn to constrain the amount of cosmoradiogenic 187 Os in the solar system and hence the age of the Galaxy. We also present evidence for extensive internal variation of 184 Os abundances in the Murchison meteorite. A steep anti-correlation is observed between ε 184 Os and ε 188 Os. Since 184 Os is formed uniquely by the p-process, this anti-correlation cannot be explained by variable addition or subtraction of s-process Os to average solar system material. Instead, this suggests that p or rprocess rich presolar grains (e.g., supernova condensates) may be present in meteorites in sufficient quantities to influence the Os isotopic compositions of the leachates. Nevertheless, 184 Os is a low abundance isotope and we cannot exclude the possibility that the measured anomalies for this isotope reflect unappreciated analytical artifacts.

A QuEChERS in house method for determining the marker residue of eprinomectin (eprinomectin B1a) by HPLC-FLD in bovine tissues and milk provided from treated animals was developed and applied. Briefly: all samples were extracted with acetonitrile using a dispersive SPE purification stage. The ascertained detection limits were 1 μg kg-1 and the quantification limits 2 μg kg-1. Recoveries on tissue samples fortified in the range of 10 μg kg-1 to 200 μg kg-1 were from 80.0% to 87.2%, with variation coefficients between 2.7% to 10.6%. The confirmation of residues in the purified extracts was made by LC-MS/MS after separation on an XTerra MS C18 (10 cm × 2.1 mm, 3.5 μm) column with a mobile phase of acetonitrile / formic acid 0.1% (97:3, v/v) at a flow rate of 0.2 mL min-1 and MRM monitoring of three characteristic ions (m/z 896.1, m/z 467.9 and m/z 329.9), resulting from the fragmentation of molecular ions [M-H]+ (m/z 914.6) of eprinomectin and the comparison of the abundance ratio of f...

A comprehensive micro‐Raman spectroscopic analysis of the Nakhla and Vaca Muerta meteorites is reported. The major and minor mineral components were identified from comparison with mineralogical standards and literature databases. The compositions of pyroxenes and olivines were obtained using only this technique and correlation data between band parameters and the chemical composition of reference materials existing in the literature. The presence of calcite in both meteorite specimens was noted; its identification inside eucrite grains in the Vaca Muerta meteorite is particularly noteworthy. Their spectral parameters show strong similarities. Aragonite associated with calcite is reported for the first time in Vaca Muerta meteorite. Spectra of siderite, which appears associated with clinopyroxenes, are also reported in Nakhla meteorite. Iron oxides were analysed in detail in both meteorites. Magnetite is the main oxide phase observed in Nakhla and goethite, lepidocrocite and magneti...

The nano-indentation technique is a suitable technique to measure hardness and elastic moduli profiles of AA6061 reinforced with Al2O3 particles, since it allows measurements of mechanical properties on a micrometer range. To investigate possible local variations in mechanical behaviour of the matrix material due to precipitation reactions being affected by the presence of ceramic reinforcements, nano-indentation tests were done on both metal matrix composite (MMC) as well as unreinforced reference material, in three different heat treatment conditions. Matrix response depends on heat treatment condition, but is approximately equal for the MMC and the base reference alloy. Due to the various imposed heat treatments, magnesium enrichment around the ceramic particles was observed, but hardness and elastic modulus of this interfacial layer could not be measured. To confirm the preferential segregation of Mg near the particle/matrix interface, linescans were made with a Scanning Electro...

The energy dependent 37 Ar(n,p) 37 Cl and 37 Ar(n,α) 34 S reaction cross sections were determined for the first time in an experimental effort involving three large facilities: the cyclotron of the UCL (Louvain-la-Neuve, Belgium) where implanted 37 Ar samples were produced; the high flux reactor of the ILL (Grenoble, France) where thermal (n,p), (n,α0) and (n,α1) cross sections of (37 ± 4) b, (1070 ± 80) b and (290 ± 50) mb respectively could be determined, and the GELINA neutron time-of-flight facility of the IRMM (Geel, Belgium) where strong resonances were observed in the keV region.

Accurate and reliable neutron capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. In particular, the accurate knowledge of {sup 234}U(n, {gamma}) reaction cross section is required for the design and realization of nuclear power stations based on the thorium fuel cycle. We have measured the neutron capture cross section of {sup 234}U at the recently constructed neutron time-of-flight facility n-TOF at CERN [2] in the energy range from 0.03 eV to 1 MeV with high accuracy due to a combination of features unique in the world: A high instantaneous neutron fluence and excellent energy resolution of the n-TOF facility, an innovative Data Acquisition System based on flash ADCs [3] and the use of a high performance 4{Pi} BaF{sub 2} Total Absorption Calorimeter (TAC) as a detection device [4, 5], In this paper, we will describe the experimental apparatus including the vario...

C. Guerrero,1,2 D. Cano-Ott,1 E. Mendoza,1 U. Abbondanno,3 G. Aerts,4 F. Álvarez-Velarde,1 S. Andriamonje,4 J. Andrzejewski,5 P. Assimakopoulos,6 L. Audouin,7 G. Badurek,8 P. Baumann,9 F. Becvár,10 F. Belloni,3 E. Berthoumieux,4 F. Calviño,11 M. Calviani,12,13 R. Capote,14,15 C. Carrapiço,16,4 A. Carrillo de Albornoz,16 P. Cennini,2 V. Chepel,17 E. Chiaveri,2 N. Colonna,18 G. Cortes,19 A. Couture,20 J. Cox,20 M. Dahlfors,2 S. David,7 I. Dillmann,21 R. Dolfini,22 C. Domingo-Pardo,23 W. Dridi,4 I. Duran,24 C. Eleftheriadis,25 M. Embid-Segura,1 L. Ferrant,7 A. Ferrari,2 R. Ferreira-Marques,17 L. Fitzpatrick,2 H. Frais-Koelbl,26 K. Fujii,3 W. Furman,27 I. Goncalves,16 E. González-Romero,1 A. Goverdovski,28 F. Gramegna,12 E. Griesmayer,26 F. Gunsing,4 B. Haas,29 R. Haight,30 M. Heil,21 A. Herrera-Martinez,2 M. Igashira,31 S. Isaev,4 E. Jericha,8 F. Käppeler,21 Y. Kadi,2 D. Karadimos,6 D. Karamanis,6 V. Ketlerov,28,2 M. Kerveno,9 P. Koehler,32 V. Konovalov,27,2 E. Kossionides,33 M. Krtičk...

This work presents the results of an investigation of the lacquer objects excavated from a Chu tomb in China (Warring States, 481e221 BC). This study is engaged in the examination of the methods and the materials used for the urushi coating on the objects. X-Ray fluorescence and Scanning Electron Microscopy/Energy Dispersive Using X-Ray (SEM/EDX) analyses were applied for the pigment identification. The results show that vermilion was for the red colour, while carbon black was for the black colour. Pyrolysis gas chromatography and mass spectrometry (Py-GC/MS) was applied for the characterization of the lacquer resulting that it is based on urushi. The possibility to classify the drying oil (tung or linseed oil) present in the lacquer is highlighted and discussed in this paper. Py-GC/MS with in-situ hydrolysis and methylation reagent tetramethylammonium hydroxide (TMAH) were performed on reference materials of linseed oil and tung oil as well as on the lacquer object samples. The results show that it is possible to unambiguously identify the drying oil, in our case, linseed oil was identified to retard the rate of hardening.

The present work has the objective of an exploratory study on the use of Informatics in Education, analyzing types of educational software with constructivist characteristics for use in basic education. The article promotes a discussion and analysis of historical factors on the use of these technologies, as well as the government incentives for this area. As a result, a pedagogical script was designed and programmed for the informational application in the classroom from a teaching activity using software with constructivist characteristics.

Background: As part of the NIH/National Heart, Lung and Blood Institute Contract for the Standardization of Lipoprotein(a) [Lp(a)] Measurements, a study was performed in collaboration with the IFCC Working Group for the Standardization of Lp(a) Assays. The aims of the study, performed with the participation of 16 manufacturers and 6 research laboratories, were to evaluate the IFCC proposed reference material (PRM) for its ability to transfer an accuracy-based value to the immunoassay calibrators and to assess concordance in results among different methods.Methods: Two different purified Lp(a) preparations with protein mass concentrations determined by amino acid analysis were used to calibrate the reference method. A Lp(a) value of 107 nmol/L was assigned to PRM. After uniformity of calibration was demonstrated in the 22 evaluated systems, Lp(a) was measured on 30 fresh-frozen sera covering a wide range of Lp(a) values and apolipoprotein(a) [apo(a)] sizes.Results: The among-laborato...

O consumo de plantas medicinais para fins terapêuticos é reconhecido como uma das formas mais antigas no tratamento de doenças. Atualmente 80% da população mundial, predominantemente em países em desenvolvimento, dependem da medicina tradicional [1], devido principalmente aos seus baixos custos. A preocupação com o uso excessivo de drogas sintéticas faz a população optar por tratamentos naturais. Entretanto, as plantas medicinais podem conter além dos elementos essenciais, também os tóxicos que mesmo em baixas concentrações são prejudiciais à saúde humana. Consequentemente, as determinações de elementos químicos em plantas medicinais são de grande interesse para o posterior estudo da correlação entre os elementos encontrados com as suas atividades terapêuticas e para identificação de seus riscos à saúde humana. Neste trabalho foi dada a continuidade às análises de plantas medicinais aplicando o método de Análise por Ativação com Nêutrons (NAA).

She teaches lecture and laboratory courses in the areas of manufacturing, automation, and computer-aided design. Morse earned a B.S.I.E. from the University of Tennessee, Knoxville, and a M.S. in manufacturing systems engineering from Auburn University, where she also worked with Auburn Industrial Extension Service. Her work in industry includes engineering experience in quality control, industrial engineering, and design and development functions for automotive parts manufacturers in North Carolina and Germany.

The design and testing of a reference material for the calibration of optical systems for strain measurement is described, together with the design and testing of a standardized test material that allows the evaluation and assessment of fitness for purpose of the most sophisticated optical system for strain measurement. A classification system for the steps in the measurement process is also proposed and allows the development of a unified approach to diagnostic testing of components or sub-systems in an optical system for strain measurement based on any optical technique. The results described arise from a European study known as SPOTS whose objectives were to begin to fill the gap caused by a lack of standards.

Radium isotopes, particularly 226 Ra and 228 Ra, pose environmental concerns due to their long half-lives (1600 years and 6 years, respectively) and their persistence in soils and sediments, especially in regions affected by coal combustion and uranium mining. This study introduces a novel deconvolution method

Methods for the determination of the actinide elements m water, biological, soil and sediment samples have been developed usmg on-line sohd phase extraction and high performance liquid chromatography (I{PLC) coupled with mductively coupled plasma mass spectrometry (ICP-MS) Initial applications utilised a commercially available resm, namely TRU-Spec resin, for efficient removal of the matrix pnor to elution of uranium and thorium analytes Comparative analyses of reference matenals and natural water samples from Plymouth and Dartmoor demonstrated significant improvement m precision and speed of analysis by using TRU-Spec coupled to ICP-MS compared with alpha spectrometry. Further applications of the TRU-Spec resin for the determination of the transuranic actinide elements neptunium, plutonium and americium, resulted m the successful determination of Pu and 7Np in biological reference matenals Detection limits were 700, 850, and 600 attograms (ag) for 7Np, Pu, and 241Am, respectively, ...