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1.
The objective of this paper was to assess the air pollution and the main sources of Air Particulate Matter in the Setúbal urban/industrial area, Portugal. PM2.5 and PM2.5?C10 were sampled in Nuclepore filters and lichens transplants were exposed during 9?months. The levels of elements in these two matrixes were measured by INAA and PIXE. A large data base was created and source apportionment was performed by using Principal Component Analysis. The results showed that the main sources of fine particles were anthropogenic and were related with traffic and local industry. There was an important contribution of natural sources, mainly for the coarse fraction, associated with the sea and the soil. Lichens characterization and mapping showed that different site-specific characteristics controlled the spatial distribution of different elements. This study showed that biomonitoring is an effective complementary method to traditional sampling systems.  相似文献   

2.
Building on last years conference discussion of "mapping the road to analytical quality with OPSpecs charts", this paper focuses on new technology and training to support and improve analytical quality management. Rigorous QC planning is complicated by the need to consider multiple decision levels, differences in method performance at each of these decision levels, multiple formats of quality requirements (allowable total error, medically important changes, biologic goals), and multiple QC designs (e.g., startup design, monitor design, average of normal design). Developments in computer technology can facilate dealing with these complications. In addition, the development of Internet training materials and courses can support and improve the technical management skills of laboratory personnel.  相似文献   

3.
In the United States of America, point-of-care testing (POCT) generally is defined as laboratory testing performed at or near the patient. The objective is to have results immediately available to clinicians for timely medical intervention. The widespread use of POCT is, in part, a response to advances in technology and increased patient acuity. Theoretically, in the context of the entire health care system, POCT improves "quality" by promoting cost through quicker diagnosis and treatment, which in turn leads to faster recovery, reduced length of stay, more efficient clinicians, and overall better utilization of resources. Total quality management (TQM) generally is associated with improving processes and, therefore in this context, improving patient outcomes. The TQM philosophy focuses on creating products or services, which meet or exceed customer expectations. The successful implementation of POCT in a manner consistent with TQM principles requires assessment of direct, measurable benefits including cost-effectiveness to the health care system.  相似文献   

4.
In this study we report on the comparison between the total selenium in serum (total Se) with that which is apparently bound to high molecular weight (>12,000 D) species, presumably proteins (bound Se). Nine hundred seventy seven (977) serum samples arising out of a population-based epidemiological study were prepared in duplicate for the determination of total Se by pipeting directly into irradiation vials; and separate duplicate aliquots were dialyzed against DI water for the determination of bound Se. All samples were analyzed by neutron activation analysis via77mSe (17.4 s). A small dialyzable Se component (6%) (free Se), defined as the difference between the total Se minus the bound Se, was identified.  相似文献   

5.
At the laboratory for INAA in Delft, the final approval of the analysis' report partly depends on the quality of the results of simultaneously processed reference materials (RM's). An extensive databank exists holding the information on RM type and analysis conditions. This information can be convented into control charts. The control charts can display (1) an element concentration in one RM as a function of moment of analysis, (2) an element concentrations in one RM as a function of the concentration of an interfering element, (3) an element concentration in all RM's, and (4) the nomalized concentrations of all elements in one RM. The inspection of the various chats facilitates the decision on, e.g., the need for renewed standardization, the fitness-for-use of a RM, any analyst-dependent results, rigidity of the spectrum analysis software etc.  相似文献   

6.
High-quality and reliable laboratory services are important components of effective and well-functioning health systems. Accurate, reliable and timely medical laboratory testing is crucial to patient care and disease surveillance. Unfortunately, in many sub-Saharan African countries, medical laboratory systems are adversely affected by the unavailability of medical laboratories, poor laboratory infrastructure and lack of well-trained personnel [1]. Quality in the laboratory is only achieved in a systematic way through the implementation of a quality management system. The results of the study showed that approximately 60?% of the 78 respondents were unaware of the requirements of ISO 15189:2007. A trial of proficiency testing, termed ??blind proficiency testing??, was carried out in which 19 laboratories determined the concentrations of urea and cholesterol in a proficiency testing material. Of the 19 laboratories that determined the concentration of urea, 63?% produced satisfactory results with scores between ?2 and +2. Similarly, 63?% of the participating laboratories obtained satisfactory z scores for cholesterol determination. Some of the laboratories that obtained satisfactory scores for urea determination had unsatisfactory scores for cholesterol determination and vice versa. It is recommended that the Ghanaian government pass a law and establish a standard to regulate medical laboratories in Ghana in order to improve quality in a significant way.  相似文献   

7.
In the present study a method using enriched stable isotope tracer and instrumental neutron activation analysis (INAA) was developed to study the dynamic distribution of rare earth elements (REEs) in a variety of organs and tissues of Wistar rats. Stable isotopes 152Sm and 168Yb were selected as tracers for the experiment. Intravenously injected 152Sm and 168Yb in chloride form could be quickly absorbed and distributed in almost all the organs and tissues of interest, including liver, skeleton, kidney, spleen, heart, lung, testicle, and blood serum. Liver and skeleton had high ability to take up 152Sm and 168Yb under the experimental conditions, whereas the contents of the elements in other organs were generally lower than 2% of the given dose during the whole experimental period. The difference in distribution of 152Sm and 168Yb in the body was also discussed.  相似文献   

8.
This article describes the current state of the art in the accreditation of chemical laboratories, both in Europe and world-wide, emphasising the most common discussion topics. The results of recent proficiency testing in chemical laboratories are summarised to draw conclusions on the performance of accredited laboratories.  相似文献   

9.
10.
The environmental changes that occurred in different periods can be identified through the increase or decrease of the concentrations of metals and other substances throughout sediment cores. The purpose of this study was to determine Al, As, Ba, Br, Cs, Eu, K, La, Mn, Sb, Sc, Sm, Th, Ti, U and V in a sediment core collected from S?o Paulo State South Seashore. Instrumental neutron activation analysis followed by gamma-ray spectrometry was the analytical method used. Results showed an abrupt decrease in the concentration of all elements in the 132–134 cm layer depth. This finding indicates an impact of anthropic activity.  相似文献   

11.
12.
Environmental monitoring requires reliable and effective analytical techniques for widely different concentration ranges. Two such methods (INAA and XRFA) were applied in a comparative environmental study on air dust filters and grass. The samples were collected during one year at two locations (near Bucharest/Romania and near Stuttgart/Germany) with different levels of air pollution. Seventeen environmentally relevant elements (As, Ba, Br, Ca, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Sb, Se, V, Zn) were determined. The aim was to test the suitability of INAA and XRFA methods for different elements in these kinds of samplesaat realistical pollution levels. The results were statistically compared for 13 elements, which were determined by both analytical techniques. They were also used to characterize the air pollution level and its variation at the two locations, and to compare them. Generally, concentrations in air of the elements studied are higher in Bucharest than in Stuttgart.  相似文献   

13.
In the FAPAS proficiency testing scheme, participants are asked to state whether the analytical method used was accredited or not accredited. It is thus possible to compare the stated accreditation status with performance in the scheme. For this purpose, fifty qualifying examples of analyte-test material combination were selected at random from the reports from the year 2006. The accredited/non-accredited subsets of results from each example were subjected to a statistical analysis to determine whether any significant differences between the distributions of results could be detected. Outliers were removed from the datasets before the main statistical tests and considered separately. The inlying data were subjected to non-parametric tests for differences in central tendency and dispersion. A few significant examples were found, but could be reasonably attributed to chance. Among the inliers there were no grounds to reject the overall null hypothesis, that is, that accreditation has no effect on performance. However, the proportion of outliers was about twice as high among the non-accredited group.  相似文献   

14.
In this study the sensitivity of the erythemally effective radiation to uncertainties in operationally measured total ozone content of the atmosphere (TOC) was estimated. For this, daily operational TOC measurements from different instruments were applied covering the period from 1997 to 1999. Measurements were gained from space by Earth Probe Satellite, Earth Remote Sensing satellite/Global Ozone Monitoring Experiment and Operational Vertical Sounder and from the ground by Dobson and Brewer spectrophotometers for the locations of Hradec Kralove (Czech Republic, 50 degrees N), Nairobi (Kenya, 1 degrees S) and Springbok (Republic of South Africa, 30 degrees S). The values were used as input parameter to model calculations of erythemally effective irradiance and daily radiant exposure. The differences due to the use of TOC from different sources were analyzed with respect to the Ultraviolet Index (UVI). The UVI was introduced as a tool for sun protection and health care. Therefore, it is of special importance to know the restriction of accuracy. As a tool of health care, the maximum uncertainties are of interest and are described in using the 95%-percentile and the maximum differences. This study shows that differences, i.e. uncertainties (95%-percentile) are in the order of 1 UVI. Independently on the location, however, extreme differences may overstep 3 UVI. For the daily dose the 95%-percentile is around 7.5 UVI hours (UVIh) but differences higher than 20 UVIh were also found.  相似文献   

15.
A study of a basic alkaline rock has been carried out using instrumental neutron activation (INAA), X-ray fluorescence (XRF) and wet chemical analyses techniques. Elemental composition and major oxides have been reported. The rock is found to be rich in K2O, Na2O, MgO, CaO, Al2O3, and Ti–Fe minerals. The transition elements are also fairly concentrated in the rock. The analyses show the igneous nature of the rock from a high potassic origin.  相似文献   

16.
A set of certified Reference Materials was prepared consisting of four natural agricultural soils with normal (n) and elevated (e) levels of element contents: CRM 7001 Light Sandy Soil (n), CRM 7002 Light Sandy Soil (e), CRM 7003 Silty Clay Loam (n), and CRM 7004 Loam (e). In these materials, certified and/or information values of the total contents of the elements As, Ba, Be, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, V and Zn, and their fractions extractable by aqua regia, boiling and cold 2M nitric acid were derived from an interlaboratory comparison in which 28 laboratories participated. Highly precise and accurate procedures of instrumental neutron activation analysis (INAA) were employed for homogeneity testing and also for certification of the total element contents. For comparation purposes, NIST SRM-2704 Buffalo River Sediment was analyzed by INAA, as well. The INAA results obtained compared very well with the certified and/or information values for four soil CRMs and also with NIST values for SRM-2704. From this agreement, a very high reliability of the new soil CRMs can be inferred.  相似文献   

17.
Systematic studies on art objects using instrumental neutron activation analysis and neutron autoradiography have been carried out in the Institute of Nuclear Chemistry and Technology in collaboration with the Faculty of Art Conservation and Restoration of the Academy of Fine Arts in Cracow, as well as with other Academies of Fine Arts and museums in Poland. It was possible to accumulate a number of essential data on the concentration of trace elements particularly in chalk grounds and pigments (such as lead white, lead-tin yellow, smalt), Chinese porcelain, Thai ceramics, as well as in the clay fillings of sarcophagi of Egyptian mummies. The above mentioned examination of art objects prior to their conservation helps to determine precisely the materials used in the process of creating art objects, as well as to identify the approximate place of origin of particular materials.  相似文献   

18.
Whilst there can be no doubt as to the benefit that an independent 3rd party conformity assessment accreditation body plays in ensuring the competency of results, personnel and processes, it is often at the expense of an adversarial relationship with the laboratory community it serves. A significant improvement in this relationship can be obtained by the formation and active participation by an independent laboratory association. This paper describes such an organisation, how it was formed, what role and the functions it currently performs and, most importantly, how it interacts with the national accreditation body and the stakeholders who are its members.  相似文献   

19.
Every laboratory has a need to track and control the variables that drive the quality of the results. However, each laboratory is unique and what one organization deems to be a critical process to track and control will likely differ from other organizations. Furthermore, there is more than just the end product or result that needs to be tracked and controlled. All of the intermediate products and resources play a significant role in producing the final product and each of these needs to be included in the LIMS. At a high level, this article will present ideas and opinions on the following topics in relation to implementing a LIMS process tracking and control system in a laboratory: The difference between tracking and controlling processes; What to track and control in the lab; The "product" of the laboratory; Preventing mistakes in a laboratory; Comprehensive software platform options; The value of seeing a system as opposed to imagining it; The use of barcodes in the laboratory; and an assessment on using the Risk Based Approach in deciding what to include in the tracking system.  相似文献   

20.
The major-groove BINOL-amino alcohol (S)-6 shows greatly enhanced fluorescence over the minor-groove one (S)-3. The study of a series of the major-groove BINOL-amino alcohol compounds demonstrates that the commonly accepted acid inhibition of the PET fluorescence quenching of aryl-amine compounds is not involved in the BINOL-amine sensors.  相似文献   

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