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Summary As part of an air pollution monitoring study, airborne particulate matter (PM2/PM10-2) samples were collected from 2000 to 2003 at two sampling sites in an urban region, Daejeon, the middle of Korea. Mass concentrations of both fine and coarse fractions and that of the black carbon in the fine particles were measured using the Gent stacked filter unit sampler and the smoke stain reflectometer, respectively. In the collected samples the concentrations of 24 elements were analyzed using instrumental neutron activation analysis. Monitored data were investigated for their temporal trends under different environmental conditions and their seasonal correlation patterns. Crustal enrichment factors were also estimated to establish the contribution between anthropogenic and crustal origin. Patterns for airborne particle matter (APM) and elemental concentrations, seasonal variation of some marker elements were investigated. The results can be applied for the investigation of further air pollution sources and for the evaluation of air quality.  相似文献   
2.
Instrumental neutron activation analysis was used for the analysis of 25 trace elements in airborne particulate matter (PM) for air pollution monitoring. For the collection of air samples, the Gent stacked filter unit low volume sampler and two types of Nuclepore polycarbonate filters were employed. Samples were collected at selected sampling dates in suburban and industrial regions of Daejon city in the Republic of Korea. Mass concentrations and black carbon of PM were measured, and enrichment factors were calculated. The results were used to describe the emission sources and their correlation patterns.  相似文献   
3.
Sediment samples were collected from seven locations of the MeeHo stream in Cheongju city, strained out by a sieve, dried by an oven and pulverized by an agate mortar. Instrumental neutron activation analysis (INAA) was applied for the determination of the elemental contents in the sediment samples by using the NAA #1 and #2 irradiation holes of the HANARO research reactor and HPGe gamma-ray spectrometers. Twenty-five elements were determined by a relative method with NIST SRM 2711-Montan Soil and the ranges of the elemental contents for the seven locations were identified. The contamination levels for elements such as As, Ba, Cr, Mn, Fe and Zn were compared with the guidelines of USEPA. The detection limits and combined uncertainties for the hazardous elements such as As, Ba, Cr, Mn, Sb, V and Zn were estimated under the given analytical conditions.  相似文献   
4.
Summary For the identification of air pollution sources, about 500 airborne particulate matter (PM2.5and PM10) samples were collected by using a Gent air sampler and a polycarbonate filter in an urban region in the middle of Korea from 2000 to 2003. The concentrations of 25 elements in the samples were measured by using instrumental neutron activation analysis (INAA). Receptor modeling was performed on the air monitoring data by using the positive matrix factorization (PMF2) method. According to this analysis, the existence of 6 to 10PMF factors, such as metal-alloy, oil combustion, diesel exhaust, coal combustion, gasoline exhaust, incinerator, Cu-smelter, biomass burning, sea-salt, and soil dust were identified.  相似文献   
5.
A quantitative analysis of mineral contents in several kinds of foods is needed to obtain information on a comprehensive elemental composition as well as an investigation on the effects of human health and nutrition based on the dietary intake of mineral elements. In 2012, six kinds of new Korean space foods (KSF) such as sweet pumpkin porridge, dakgalbi (spicy grilled chicken), Manila clam porridge, ox leg bone-cabbage soup, ginseng-chicken porridge, and chicken curry rice were developed by KAERI, and the contents of more than 15 elements in the samples were determined using an instrumental neutron activation analysis. A certified reference material associated with a biological food sample was used for analytical quality control. The analytical results were evaluated according to the elemental concentrations with KSF samples and compared with the reported values. These results will be applied toward the identification of gamma-irradiated foods.  相似文献   
6.

We have established an instrumental neutron activation analysis (INAA) method, including k0-based INAA, at the Korea Research Institute of Standards and Science (KRISS) for the certification of reference materials. As part of establishing INAA measurements, KRISS infant formula certified reference material was analysed for multiple elements at three different metrological institutes: KRISS and NIST for the standard comparator method, and JSI for the k0-INAA method. The mass fraction of most elements was consistent within expanded uncertainty (k?=?2). In addition, the results were used to verify the validity of elemental analysis of Zn using the standard comparator INAA at KRISS, and spreadsheet-based INAA calculations were evaluated.

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7.
For air pollution monitoring, about 1300 airborne particulate matter samples were collected by using a low volume air sampler and a polycarbonate filter at two sampling sites in an urban region, Daejeon, the middle of Korea from 2003 to 2006. Mass concentrations of the black carbon were measured using a smoke stain reflectometer. The concentrations of 24 elements in the collected samples were analyzed by using instrumental neutron activation analysis, and its temporal trends and enrichment factors were investigated under different environmental conditions. Analytical control was carried out by using certified reference materials.  相似文献   
8.
The k 0-standardization method (k 0-NAA) is known as one of the most remarkable progresses of the NAA with its many advantages. For the application of k 0-NAA method at the NAA #1 irradiation position where the neutrons are well thermalized in the HANARO research reactor, KAERI, Korea, the determination of the reactor neutron spectrum parameters such as α and f have been carried out. The measured values of α and f using the “Cd-ratio” triple monitor method were 0.127±0.022 and 1010±70, respectively. To evaluate the applicability of k 0-NAA in our analytical system, the analysis of three kinds of SRMs was executed. The analytical results showed that the relative error of most of the elements was less than 10% and the U-scores were within 2. It is turned out that the procedure of the k 0-NAA in the HANARO research reactor is available for a practical application in the environmental fields.  相似文献   
9.

Three irradiation holes coupled to a pneumatic transfer system were installed for neutron activation analysis in the Jordan Research and Training Reactor (JRTR), which is the first research reactor in Jordan. To perform instrumental neutron activation analysis, neutron spectrum parameters, such as thermal neutron flux, α and f for the irradiation holes, should be measured. The Cd-ratio method was applied for the determination of the aforementioned parameters. For this purpose, 0.1% Au–Al wires and Zr foils were irradiated with and without Cd-cover, and the Cd ratios were determined for Au-198, Zr-95, and Zr-97/Nb-97m nuclides. Then, the parameters were calculated and determined at three irradiation holes.

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