Average daily contributions (90% CI black bar) to PM10 in relative (%, left pie charts), OPAA and OPDTT per source’s mass in absolute (OPm in nmol/min m−3, middle bar plot) and OPAA and OPDTT per ...volume in relative (OPv in %, right bar plot) values grouped according to sources common activities. Arrows indicate (additional) associations between the sources.
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•Concentrations of PM10 at the site are comparable to other Alpine valleys, however, OP levels are higher compared to European sites.•Extensive tests with PMF were performed including organic tracers.•The most important sources of PM10, OP per µg of source as well as OP per m3 at the site are biomass burning and activities related to cement production.•Sources with important contributions to PM10 do not necessarily have high OP.•An unusual chloride-rich source was identified with high OP per µg of source.
Toxicity of particulate matter (PM) depends on its sources, size and composition. We identified PM10 sources and determined their contribution to oxidative potential (OP) as a health proxy for PM exposure in an Alpine valley influenced by cement industry. PM10 filter sample chemical analysis and equivalent black carbon (eBC) were measured at an urban background site from November 2020 to November 2021. Using an optimized Positive Matrix Factorization (PMF) model, the source chemical fingerprints and contributions to PM10 were determined. The OP assessed through two assays, ascorbic acid (AA) and dithiothreitol (DTT), was attributed to the PM sources from the PMF model with a multiple linear regression (MLR) model. Ten factors were found at the site, including biomass burning (34, 40 and 38% contribution to annual PM10, OPAA and OPDDT, respectively), traffic (14, 19 and 7%), nitrate- and sulphate-rich (together: 16, 5 and 8%), aged sea salt (2, 2 and 0%) and mineral dust (10, 12 and 17%). The introduction of innovative organic tracers allowed the quantification of the PM primary and secondary biogenic fractions (together: 13, 8 and 21%). In addition, two unusual factors due to local features, a chloride-rich factor and a second mineral dust-rich factor (named the cement dust factor) were found, contributing together 10, 14 and 8%. We associate these two factors to different processes in the cement plant. Despite their rather low contribution to PM10 mass, these sources have one of the highest OPs per µg of source. The results of the study provide vital information about the influence of particular sources on PM10 and OP in complex environments and are thus useful for PM control strategies and actions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPUK, ZAGLJ, ZRSKP
The extension of cable lines in the electric power system also increases the need to ensure their reliability. This can be enhanced by monitoring of characteristic parameters which are directly ...correlated with the condition of the cable system insulation. However, the long-term reliability of the cable network depends decisively on both the cable and its pertaining accessories. There is an important difference between cables and accessories concerning the manufacturing process. Cables are made in factories under closely controlled conditions, whereas accessories must be assembled on site. It is also essential that testing and measurements of a cable line are made immediately after laying, which allows for obtaining of data on the characteristic parameters representing the initial or zero state. The paper will discuss challenges regarding field testing of high voltage 110 kV cables using ACRF system and other testing equipment for executing on-site commissioning tests where the main purpose was finding of irregularities, weak points and how to increase the quality of test results.
Medium-voltage cables represent an important component of the Nuclear Power Plant (NPP) nuclear island as well as of its balance of plant. Therefore, it is reasonable to monitor their aging process ...and expected reliability. There are, however, many electrical, thermal, mechanical and radiation stresses, which, through time, can influence the occurrence of insulation degradation. Assessment and evaluation of the condition of cable insulation is supposed to be carried out periodically, during the scheduled outages and maintenance activities. Accordingly, it is necessary to carefully select the proper efficient diagnostic methods and different scrutinises, particularly studied and purposeful for determining the aging grade and overall adequacy of the cable insulation. To avoid unplanned failures with loss of critical equipment, the insulation must be properly tested. Therefore electrical and non-electrical diagnostic methods are used to ensure proper assessment of cable insulation deterioration. This paper reports on experience with application of different diagnostic methods boosting tendency to improve monitoring of the condition of the cable insulation in the NPP Krško, The diagnostic testing and measurements on cables recommended to be done in nuclear power plant respecting a good practice of asset maintenance management is discussed.
Hum je izredno obiskana vzpetina ne glede na vreme in letni čas. Ob veliki akciji ureditve poti na Hum l. 2005 so bili za večjo varnost in sploh boljšo opremljenost nameščeni klini, jeklenice, ...stopnice, varovalne ograje, smerokazi, napisne table ter na vrhu nova vpisna knjiga in žig.
Pot na Hum je opremljena s številnimi informacijskimi tablami. Te planinca in izletnika seznanjajo z imeni nekaterih predelov oz. zanimivosti na poti (Divji farovž, Blaževa skala, Prižnica) ali pa so ...izobraževalno-informacijske narave (tabla z opisi zavarovanih rastlin na Humu, tabla o varovanem območju narave, tabla z opisom poti na Hum).
Pot na Hum je opremljena s številnimi informacijskimi tablami. Te planinca in izletnika seznanjajo z imeni nekaterih predelov oz. zanimivosti na poti (Divji farovž, Blaževa skala, Prižnica) ali pa so ...izobraževalno-informacijske narave (tabla z opisi zavarovanih rastlin na Humu, tabla o varovanem območju narave, tabla z opisom poti na Hum).
