Wideband Characteristic Basis Functions in Radiation Problems

In this paper, the use of characteristic basis function (CBF) method, augmented by the application of asymptotic waveform evaluation (AWE) technique is analyzed in the context of the application to radiation problems. Both conventional and wideband CBFs are applied to the analysis of wire and planar antennas

Recolonization and recovery of an Arctic benthic community subject to mine-tailings deposits

Deposition of large volumes of mine tailings takes place in several Norwegian fjords, but the impacts on marine ecosystems have received relatively little scientific attention. At a 40 + − year old tailing deposition area for a copper mine in the Arctic fjord Repparfjorden, we investigated both short-term colonization of mine tailingscontaminated sediments through a field experiment, and the present faunal state in the old deposit area. Copper-concentrations at the old deposition site were still high (up to 291 mg/kg dry weight (dw)), and exceeded the Norwegian environmental-quality threshold (84 mg/kg dw). Furthermore, copper was identified as a significant structuring factor for the fauna in the fjord, although faunal diversity was relatively high and the community not severely disturbed. In the colonization experiment, experimental boxes filled with defaunated sediment capped with mine tailings were subject to colonization for 15 months. Benthic macrofaunal communities were successfully established in all boxes, but the boxes with tailings showed lower species richness, abundance and biomass than the controls. Mine tailings continue to have local impacts on seafloor communities decades after deposition, and even low levels of metal-rich sediments can affect faunal recruitment. These results have implications for submarine deposition of mining waste and the impacts they have on coastal ecosystems

Evidence of energy and nutrient transfer from invasive pink salmon (Oncorhynchus gorbuscha) spawners to juvenile Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) in northern Norway

Recent large influxes of non-native Pacific pink salmon (Oncorhynchus gorbuscha) to North European rivers have raised concern over their potential negative impacts on native salmonids and recipient ecosystems. The eggs and carcasses of semelparous pink salmon may provide a significant nutrient and energy subsidy to native biota, but this phenomenon has not been widely documented outside the species' native distribution. We analysed the stomach contents and stable isotope values (δ15N and δ13C) in muscle and liver tissues of juvenile Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) to determine whether these native salmonids utilise marine-derived nutrients and energy provided by pink salmon eggs and carcasses in the subarctic river system Vesterelva, northern Norway. Although egg foraging and assimilation of marine-derived nutrients in fish body tissues were found to be minor at the population level, a few juvenile salmon and trout had recently eaten large quantities of pink salmon eggs. Some of these individuals also had high δ15N and δ13C values, indicating a long-term diet subsidised by marine-derived nutrients and energy from pink salmon eggs. Hence, our study provides novel evidence that the eggs of invasive pink salmon may provide an energetic, profitable food resource for juvenile native fish. More research is needed to understand the broader ecological implications for fishes and other biota in river ecosystems invaded by pink salmon. egg predation, marine-derived nutrients, non-native salmonids, resource subsidy, stable isotope analysis, subarctic riverpublishedVersio

PENGARUH VARIASI SUHU PERLAKUAN PANAS MENGGUNAKAN GAS HIDROGEN TERHADAP KARAKTERISTIK TERMISTOR NTC BERBASIS Fe2O3-MnO-ZnO

Telah dilakukan pembuatan termistor NTC berbasis Fe2O3-MnO-ZnO dengan perlakuan panas yang suhunya divariasikan antara 200oC, 300oC, 400oC dan 500oC menggunakan gas hidrogen (93%Ar+7%H2). Dimana kandungan yang ada pada mineral yarosit yaitu hematit (Fe2O3) yang menjadi bahan utama termistor NTC. Proses pembuatan tersebut dimulai dengan pencampuran serbuk Fe2O3 (lokal) yang sudah digerus dengan MnO dan ZnO sampai didapatkan pasta berbasis Fe2O3-MnO-ZnO. Kemudian dilakukan proses screen printing pada film tebal mentah. Film tebal tersebut disinter pada suhu sinter 1100°C selama 2 jam. Film tebal hasil sinter dilapisi perak untuk memberikan kontak ohmik sehingga dapat dilakukan pengukuran resistansi. Resistansi film tebal diukur pada suhu 30-150oC dengan beda suhu sebesar 5oC. Film tebal yang telah diukur resistansinya, diberi perlakuan panas dengan memanaskannya pada suhu yang bervariasi di dalam atmosfer gas hidrogen. Setelah diberi perlakuan panas dilakukan kembali pengukuran resistansi. Selanjutnya dilakukan karakterisasi struktur kristal dan struktur mikro dianalisis dengan XRD dan SEM. Struktur kristal yang terbentuk yaitu hematit dan spinel, namun bertambahnya suhu perlakuan panas membuat struktur kristal cenderung amorf dan perlakuan panas yang diberikan tidak mempengaruhi ukuran butir. Hasil karakterisasi sifat listrik menunjukkan resistansi listrik menurun seiring bertambahnya suhu perlakuan panas dari 2537,67MΩ menjadi 3,69MΩ. Termistor yang memenuhi persyaratan pasar (≥2000K) yaitu yang diberi perlakuan panas pada suhu 200oC-400oC. ; NTC thermistor have been fabricated based Fe2O3-MnO-ZnO the heat treatment temperature is varied between 200oC, 300oC, 400oC and 500oC using hydrogen gas (93% Ar + 7% H2). Where the existing content on yarosit mineral is hematite (Fe2O3) which is the main ingredient of NTC thermistors. The creation process begins with the mixing of powders Fe2O3 (local) that have been crushed with MnO and ZnO based paste to obtain Fe2O3-MnO-ZnO. Then do the process of screen printing on thicker films crude. The thick film sintered at 1100°C sinter temperature for 2 hours. Thick film sintered silver coated to provide an ohmic contact resistance measurement so that it can be done. Thick film resistance measured at 30-150oC with a temperature difference of 5°C. Thick film has been measured resistance, heat-treated by heating at various temperatures in the atmosphere of hydrogen gas. After the heat treatment is carried back by resistance measurement. Further characterization of crystal structure and microstructure were analyzed by XRD and SEM. The crystal structure is formed that is hematite and spinel, but increasing the heat treatment temperature makes the crystal structure tend to be amorphous and heat treatment provided does not affect the size of the grains. The characterization results show electrical properties of electric resistance decreases as the heat treatment temperature of 2537.67MΩ be 3.69MΩ. Thermistor that meets the requirements of the market (≥2000K) is heat-treated at a temperature of 200oC-400oC

Screening studies of POP levels in bottom sediments from selected lakes in the Paz watercourse

Appendix 5/15 of the publication "State of the environment in the Norwegian, Finnish and Russian border area 2007" (The Finnish Environment 6/2007)

Screening studies of POP levels in fish from selected lakes in the Paz watercourse

Appendix 8/15 of the publication "State of the environment in the Norwegian, Finnish and Russian border area 2007" (The Finnish Environment 6/2007)

Vannkvalitetsrapport – Pasvik Overvåkingsprogrammet i grenseområdet mellom Norge, Finland og Russland)

The Pasvik monitoring programme was created in 2006 as a result of the trilateral cooperation, and with the intention of following changes in the environment under variable pollution levels. Water quality is one of the basic elements of the Programme when assessing the effects of the emissions from the Pechenganikel mining and metallurgical industry (Kola GMK). The Metallurgic Production Renovation Programme was implemented by OJSC Kola GMK to reduce emissions of sulphur and heavy metal concentrated dust. However, the expectations for the reduction in emissions from the smelter in the settlement Nikel were not realized. Nevertheless, Kola GMK has found that the modernization programme’s measures do not provide the planned reductions of sulfur dioxide emissions. In this report, temporal trends in water chemistry during 2000–2009 are examined on the basis of the data gathered from Lake Inari, River Pasvik and directly connected lakes, as well as from 26 small lakes in three areas: Pechenganikel (Russia), Jarfjord (Norway) and Vätsäri (Finland). The lower parts of the Pasvik watercourse are impacted by both atmospheric pollution and direct wastewater discharge from the Pechenganikel smelter and the settlement of Nikel. The upper section of the watercourse, and the small lakes and streams which are not directly linked to the Pasvik watercourse, only receive atmospheric pollution. The data obtained confirms the ongoing pollution of the river and water system. Copper (Cu), nickel (Ni) and sulphates are the main pollution components. The highest levels were observed close to the smelters. The most polluted water source of the basin is the River Kolosjoki, as it directly receives the sewage discharge from the smelters and the stream connecting the Lakes Salmijarvi and Kuetsjarvi. The concentrations of metals and sulphates in the River Pasvik are higher downstream from the Kuetsjarvi Lake. There has been no fall in the concentrations of pollutants in Pasvik watercourse over the last 10 years. Ongoing recovery from acidification has been evident in the small lakes of the Jarfjord and Vätsäri areas during the 2000s. The buffering capacity of these lakes has improved and the pH has increased. The reason for this recovery is that sulphate deposition has decreased, which is also evident in the water quality. However, concentrations of some metals, especially Ni and Cu, have risen during the 2000s. Ni concentrations have increased in all three areas, and Cu concentrations in the Pechenganickel and Jarfjord areas, which are located closer to the smelters. Emission levels of Ni and Cu did not fall during 2000s. In fact, the emission levels of Ni compounds even increased compared to the 1990s

Miljøutfordringer i grenseområdet mellom Norge, Finland og Russland

This report examines the human impact on the subarctic environment of the joint border area of Norway, Finland and Russia. The aim is to present the current state and recent changes that have taken place in the region. The main threat to the environment is the Pechenganikel mining and metallurgical industrial combine in the towns of Nikel and Zapolyarny in the Kola Peninsula. Emissions from this complex include high levels of heavy metals, persistent organic pollutants and sulfur dioxide. Pollution, along with climate change, water level regulation and other anthropogenic effects, has affected the aquatic ecosystems in the joint border area. The main heavy metals in the area are copper and nickel, the highest concentrations of which are measured near the combine. Direct discharge of sewage into the river continues and airborne heavy metal particles are also deposited to areas farther away. Climate changeinduced increase in temperature and precipitation in the Kola Peninsula is evident. Water level regulation with seven hydropower plants in the Pasvik River have changed it into a series of lakes and lake-like reservoirs. This report discusses modelling, which was enabled to estimate the effect of climate change on Lake Inarijärvi and the Pasvik River hydrology, water level fluctuation and ecology and to follow the sulfur dioxide emissions emitted from the Pechenganikel. Effects of pollution on the nature and concentrations of the main pollutants were studied and climate change in the border area and its effects on the ecology were estimated. Also the effects of water level regulation on the ecological status of the aquatic ecosystems were addressed