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1-Etylo-2-pirolidon. Dokumentacja proponowanych dopuszczalnych wielkości narażenia zawodowego

Klimecka Agnieszka, Czerczak Sławomir

Podstawy i Metody Oceny Środowiska Pracy

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2022

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Nr 3 (113)

119--151

PL

1-Etylo-2-pirolidon (NEP) jest cieczą bezbarwną do lekko żółtawej o zapachu zbliżonym do amoniaku. Związek jest stosowany jako zamiennik 1-metylo-2-pirolidonu (NMP), głównie jako rozpuszczalnik przemysłowy. Dla 1-etylo-2-pirolidonu dotychczas nie opracowano w Polsce dokumentacji i nie ustalono wartości normatywnych w powietrzu środowiska pracy. Zaproponowano przyjęcie wartości najwyższego dopuszczalnego stężenia (NDS) 1-etylo-2-pirolidonu na poziomie 30 mg/m³ . Za wartość NOAEC przyjęto stężenie 62,6 mg/m³ na podstawie wyników badań na szczurach, u których narażenie na związek nie spowodowało działania toksycznego na nabłonek węchowy. Ze względu na działanie drażniące związku zaproponowano przyjąć wartość chwilową na poziomie 60 mg/m³ . Obliczone na podstawie wartości NOAEL dla toksyczności prenatalnej u zwierząt równoważniki stężeń w powietrzu środowiska pracy wynoszą 87,5 i 175 mg/m³ , zatem zaproponowana wartość NDS na poziomie 30 mg/m³ powinna zabezpieczyć pracowników również przed szkodliwym działaniem na potomstwo. Biorąc pod uwagę działanie drażniące 1-etylo-2-pirolidonu, jego wchłanianie przez skórę oraz możliwe działanie toksyczne na płód, zaproponowano następujące oznakowanie związku: „skóra” – wchłanianie substancji przez skórę może być tak samo istotne, jak przy narażeniu drogą oddechową, „Ft” – substancja o działaniu szkodliwym na płód oraz „I” – substancja o działaniu drażniącym. Zaproponowano ustalenie wartości dopuszczalnego stężenia w materiale biologicznym (DSB) związku na poziomie 45 mg 2-hydroksy-N-etylosukcynoimidu (2-HESI)/g kreatyniny. Zakres tematyczny artykułu obejmuje zagadnienia zdrowia oraz bezpieczeństwa i higieny środowiska pracy będące przedmiotem badań z zakresu nauk o zdrowiu oraz inżynierii środowiska.

EN

1-Ethylpyrrolidin-2-one (NEP) is a colorless or yellowish liquid with ammonia-like odor. It is used as 1-methylpyrrolidin2-one (NMP) substitute, mostly as industrial solvent. So far, no normative values in the air of the working environment have been defined in Poland for 1-ethyl-2-pyrrolidone. The MAC value of 30 mg/m3 and STEL value of 60 mg/m³ have been proposed. The basis for calculating the MAC value was the NOAEC value of 62.6 mg/m³ for the olfactory epithelium degeneration in rats. The equivalent concentrations in the air of the working environment, calculated on the basis of the NOAEL value for prenatal toxicity in rats and rabbits, are 87.5 mg/m³ and 175 mg/m³ , respectively, therefore the MAC value of 30 mg/m³ should protect workers from harmful effects on the offspring. Taking into account the irritating effect of 1-ethyl-2-pyrrolidone, its absorption through the skin and possible toxic effects on the fetus, the following notations have been proposed: “skin” – skin absorption of the substance may be just as important as for inhalation exposure, “Ft” – substance toxic to the fetus and “I” – irritating substance. It is proposed to set Biological Exposure Index (BEI) value of 45 mg 2-hydroxy-N-ethylsuccinimide (2-HESI)/g creatinine. This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

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Sub-THz radiation room temperature sensitivity of long-channel silicon field effect transistors

Sizov F., Golenkov A., But D., Sakhno M., Reva V.

Opto-Electronics Review

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2012

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Vol. 20, No. 2

194-199

EN

Room temperature operating n-MOSFETs (n-type metal-oxide silicon field effect transistors) used for registration of sub-THz (sub-terahertz) radiation in the frequency range v = 53-145 GHz are considered. n-MOSFETs were manufactured by 1-µm Si CMOS technology applied to epitaxial Si-layers (d ≈15 µm) deposited on thick Si substrates (d = 640 µm). It was shown that for transistors with the channel width to length ratio W/L = 20/3 µm without any special antennas used for radiation input, the noise equivalent power (NEP) for radiation frequency v ≈76 GHz can reach NEP ∼6x10⁻¹⁰ W/Hz¹/². With estimated frequency dependent antenna effective area Sest for contact wires considered as antennas, the estimated possible noise equivalent power NEPpos for n-MOSFET structures themselves can be from ∼15 to ∼10³ times better in the specral range of v ∼55-78 GHz reaching NEPpos ≈10⁻¹² W/Hz¹/².

3

Forecasting carbon budget under climate change and CO2 fertilization for subtropical region in China using Integrated Biosphere Simulator (IBIS) model

Zhu Q., Jiang H., Liu J., Peng C., Fang X., Yu S., Zhou G., Wei X., Ju W.

Polish Journal of Ecology

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2011

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Vol. 59, nr 1

3-23

EN

The regional carbon budget of the climatic transition zone may be very sensitive to climate change and increasing atmospheric CO2 concentrations. This study simulated the carbon cycles under these changes using process-based ecosystem models. The Integrated Biosphere Simulator (IBIS), a Dynamic Global Vegetation Model (DGVM), was used to evaluate the impacts of climate change and CO2 fertilization on net primary production (NPP), net ecosystem production (NEP), and the vegetation structure of terrestrial ecosystems in Zhejiang province (area 101,800 km2, mainly covered by subtropical evergreen forest and warm-temperate evergreen broadleaf forest) which is located in the subtropical climate area of China. Two general circulation models (HADCM3 and CGCM3) representing four IPCC climate change scenarios (HC3AA, HC3GG, CGCM-sresa2, and CGCM-sresb1) were used as climate inputs for IBIS. Results show that simulated historical biomass and NPP are consistent with field and other modelled data, which makes the analysis of future carbon budget reliable. The results indicate that NPP over the entire Zhejiang province was about 55 Mt C yr[^-1] during the last half of the 21st century. An NPP increase of about 24 Mt C by the end of the 21st century was estimated with the combined effects of increasing CO2 and climate change. A slight NPP increase of about 5 Mt C was estimated under the climate change alone scenario. Forests in Zhejiang are currently acting as a carbon sink with an average NEP of about 2.5 Mt C yr[^-1]. NEP will increase to about 5 Mt C yr[^-1] by the end of the 21st century with the increasing atmospheric CO2concentration and climate change. However, climate change alone will reduce the forest carbon sequestration of Zhejiang.s forests. Future climate warming will substantially change the vegetation cover types; warm-temperate evergreen broadleaf forest will be gradually substituted by subtropical evergreen forest. An increasing CO2 concentration willhave little contribution to vegetation changes. Simulated NPP shows geographic patterns consistent with temperature to a certain extent, and precipitation is not the limiting factor for forest NPP in the subtropical climate conditions. There is no close relationship between the spatial pattern of NEP and climate condition.

4

THz/sub-THz bolometer based on electron heating in a semiconductor waveguide

Dobrovolsky V., Sizov F.

Opto-Electronics Review

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2010

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Vol. 18, No. 3

250-258

EN

Direct detection THz/sub-THz bolometer is proposed. In it an electromagnetic wave propagates in the bipolar semiconductor waveguide, heats electrons and holes there, and therefore creates their bipolar thermodiffusion flow and, as well as, the electromotive force (emf). The flow causes the carrier excess concentration. Both this concentration and emf are used to get the bolometer response voltage. The bolometer theoretical model is developed. The possibility without cooling or moderate cooling (about 100 K for the Cd₀.₂Hg₀.₈Te bolometers) to get acceptable for applications values of the noise equivalent power is shown. Experimental results confirm the main model conclusions.