Waste co-combustion in boilers

Przedstawiono wybrane aspekty problematyki związanej ze współspalaniem odpadów w kotłach energetycznych. Podjęcie współspalania w istniejących instalacjach wymaga na ogół modernizacji układów technologicznych, co wiąże się z określonymi kosztami. Ponadto ulegają zmianie warunki eksploatacji instalacji, zarówno w kontekście pracy kotła (pogorszenie spalania, emisje itp.), jak i w kontekście wymogów formalno prawnych. Obostrzenia formalne zależą przede wszystkim od rodzaju substancji, które mają być spalane i ich kwalifikacji jako odpadów lub biomasy. Zarządzający instalacjami muszą więc liczyć się z możliwością zaostrzenia norm emisji dla kotłów, koniecznością instalowania dodatkowych urządzeń kontrolno-pomiarowych, czy też z obowiązkiem dotrzymania określonych poziomów parametrów procesowych.The paper introduces chosen aspects of combustion and co-combustion of biomass and waste in existing boilers. An initiation of co firing in power-installations demands, in general, modernization of technological systems, what causes an investment costs. This leads to change a maintenance conditions of installation, both in context of boiler operation (worsening of combustion, pollutants etc.), as well as legal requirements. Restrictions depend first of all from kind of fuels which have to be burnt and their classification as waste or biomasses. Installation management must make allowance for possibility of more restrictive emission standards for boilers, with necessity of installation of additional monitoring, or with the duty to keep a definite levels of process parameters

Modelling COVID-19 contagion: risk assessment and targeted mitigation policies

We use a spatial epidemic model with demographic and geographic heterogeneity to study the regional dynamics of COVID-19 across 133 regions in England. Our model emphasises the role of variability of regional outcomes and heterogeneity across age groups and geographic locations, and provides a framework for assessing the impact of policies targeted towards sub-populations or regions. We define a concept of efficiency for comparative analysis of epidemic control policies and show targeted mitigation policies based on local monitoring to be more efficient than country-level or non-targeted measures. In particular, our results emphasise the importance of shielding vulnerable sub-populations and show that targeted policies based on local monitoring can considerably lower fatality forecasts and, in many cases, prevent the emergence of second waves which may occur under centralised policies.</p

Liquidity at risk: joint stress testing of solvency and liquidity

The traditional approach to the stress testing of financial institutions focuses on capital adequacy and solvency. Liquidity stress tests have been applied in parallel to and independently from solvency stress tests, based on scenarios which may not be consistent with those used in solvency stress tests. We propose a structural framework for the joint stress testing of solvency and liquidity: our approach exploits the mechanisms underlying the solvency-liquidity nexus to derive relations between solvency shocks and liquidity shocks. These relations are then used to model liquidity and solvency risk in a coherent framework, involving external shocks to solvency and endogenous liquidity shocks arising from these solvency shocks. We define the concept of 'Liquidity at Risk', which quantifies the liquidity resources required for a financial institution facing a stress scenario. Finally, we show that the interaction of liquidity and solvency may lead to the amplification of equity losses due to funding costs which arise from liquidity needs

MÖSSBAUER STUDY OF PROTON RADIATION EFFECTS IN PERMALLOY

No abstract availabl

SKIN DEPTH EFFECT IN THE RF COLLAPSE STUDIES

No abstract availabl

Modelling COVID-19 contagion: risk assessment and targeted mitigation policies

We use a spatial epidemic model with demographic and geographical heterogeneity to study the regional dynamics of COVID-19 across 133 regions in England. Our model emphasizes the role of variability of regional outcomes and heterogeneity across age groups and geographical locations, and provides a framework for assessing the impact of policies targeted towards subpopulations or regions. We define a concept of efficiency for comparative analysis of epidemic control policies and show targeted mitigation policies based on local monitoring to be more efficient than country-level or non-targeted measures. In particular, our results emphasize the importance of shielding vulnerable subpopulations and show that targeted policies based on local monitoring can considerably lower fatality forecasts and, in many cases, prevent the emergence of second waves which may occur under centralized policies

Hyperfine interactions

Although the effects of impurities in metallic magnets have been extensively studied there have been far fewer experiments on impurities in insulating magnets, and, in an effort to understand this problem, we have investigated the effect of impurities in various systems. In MnCl2⋅4H2O samples doped with 1.6, 4.0 and 6.2% Co, the 54Mn NMRON line is significantly broadened compared to the line in the pure crystal and shows structure on the low frequency side. The nuclear spin-lattice relaxation time is also lower by an order of magnitude. 54Mn has also been doped into FeCl2⋅4H2O for which a 4-sublattice structure has been proposed and some details of this structure have been obtained

Frequency pulling effects in the quasi-two-dimensional ferromagnet 54Mn−Mn(COOCH3)2⋅4H2O studied by nuclear orientation techniques

Continuous wave NMR thermally detected by nuclear orientation has been used to investigate the magnetic properties and spin dynamics of the quasi-two-dimensional ferromagnet 54Mn−Mn(COOCH3)2⋅4H2O. The system exhibits a frequency pulling effect due to the indirect Suhl-Nakamura interaction between nuclear spins and the electronic spin excitation spectrum is related to the coupling strength of the nuclear spins. The temperature dependence of the frequency pulling effect was measured for the two crystalline sublattices Mn1 and Mn2 in low magnetic field. The spectra show a structure not predicted theoretically. The current theory is valid only for I=1/2 with uniaxial crystalline anisotropy fields. The theory of frequency pulling has been extended here to the case of I>~1/2 and nonuniaxial crystalline anisotropy fields and the resonant frequencies and linewidths have been calculated as a function of temperature. The new theory and data agree well in terms of the magnitude and temperature dependence of the frequency pulling. Discrepancies are likely due to simplifying assumptions when calculating the electronic magnon spectrum. Classical and quantum numerical simulations confirm qualitatively the predictions of the model