The resistance of mortars with fluidized beds boiler fly ashes and conventional fly ashes to acid corrosion

This paper presents the results of research undertaken to determine the impact of the aggressive environment of acid corrosion on the durability of cement mortars with the participation of fluidized beds boiler fly ashes and conventional fly ashes used separately and in the form of mixtures. The beneficial effect of fluidized beds boiler fly ashes on the physical properties of cement mortars has been shown, i.e. reduction of the contraction, decrease of weight loss and reduction of the destruction of mortars in acid corrosion. This effect was especially beneficial for mortars containing higher (45% by weight) content of fluidized fly ashes, used separately and in the form of mixtures, regardless of the aggressiveness of the environment (1%, 3% and 5% HCl solution)

The influence of flue gas denitrification process applied in energy industry on the quality of fly ashes and cements with their content

Dyrektywy Unii Europejskiej dotyczące zmniejszenia emisji tlenków azotu (NOx) do atmosfery przez przemysł energetyczny wymuszają stosowanie nowych technologii odazotowania spalin. Taki proces może negatywnie wpływać na jakość ubocznych produktów spalania (UPS) [1–2]. Dlatego podjęto badania mające określić wpływ zawartości amoniaku na właściwości popiołów lotnych. Objęto nimi popioły lotne krzemionkowe ze spalania węgla kamiennego oraz popioły fluidalne ze spalania węgla brunatnego. Dla wytypowanych próbek popiołów pochodzących z instalacji, w których wprowadzono system odazotowania spalin, oznaczono zawartość amoniaku w suchej masie oraz w wyciągu wodnym. Określono wpływ zawartości amoniaku w popiołach lotnych na właściwości wytrzymałościowe cementów z ich udziałem. Wykonano również analizy wpływu czasu wietrzenia na zawartość azotu amonowego w suchej masie popiołów. Do zbadania procesu wydzielania się amoniaku zastosowano metodę analizy termicznej.European Union imposes ordinances which referred to reduction of nitrogen oxides emission to atmosphere emitted by energy industry. New flue gasses denitrification technologies have to be applied to cope with that directives. Unlikely this process may negatively influence on the combustion by-products quality. For this reason the research aimed to test the influence of ammonia content in fly ashes on their properties had been proceeded. In this research the fly ashes from conventional combustion of coal and FBC (fluidized bed combustion) fly ashes from combustion of lignite were used. For chosen fly ash samples originated from flue gas denitrification installations, the ammonia content in dry mass and water extracts was tested. Moreover the influence of ammonia content in fly ashes on strength of cement-ash mortars was studied. The effect of airing time on ammonia quantity in dry mass was analyzed. To investigate the process of ammonia evolution, the differential thermal analyses were carried out

Recombinants of PVY Strains Predominate Among Isolates from Potato Crop in Poland

plex Reverse Transcription-Polymeraze Chain Reaction (RT-PCR). Recombinants of PVY strains predominate among the isolates tested. Using one-step triplex RT-PCR most PVYN-Wi isolates were classified as subgroup PVYNWi-P and most PVYN and/or PVYNTN isolates as the recombinant PVYNTN strain. A recombinant PVYNTN isolate (12/94) and two additional PVYN and/or PVYNTN isolates were not detect-ed by one-step triplex RT-PCR. Twelve isolates were identified as the PVYO strain but PVYN, non-recombinant PVYNTN and PVYC strains were not found. Serological and biological assays of 144 isolates of PVYN-Wi strain showed that 100 isolates were the expected PVYO serotype with vein necrosis (VN) symptoms on tobacco. However, 10 isolates of the PVYNWi-P subgroup exhibited vein clearing (VCl) on tobacco and 2 isolates of the PVYNN242 subgroup unexpectedly exhibited as the PVYN serotype. All the isolates of PVYN-Wi strain induced severe local lesions (LL) on Chenopodium amaranticolor. Out of 126 isolates of PVYNTN strain tested, 76 were typical PVYN serotype with VN on tobacco, but their reactions on C. amaranticolor were different: 13 isolates did not show symptoms, 23 isolates induced weak, and 40 isolates induced severe LL. The remaining isolates of PVYN-Wi, PVYN and/or PVYNTN or PVYO were serologically PVYN and PVYO positive or exhibited unpredictable serological and biological reactions

Potato virus Y: Control, Management and Seed Certification Programmes

The management of Potato virus Y (PVY) in potato crops poses a continual challenge due to the non-persistent mode of transmission of the virus and the propagation of seed potato tubers over several generations in the field. While PVY-resistant cultivars remain the most efficient way to protect potato crops against PVY, a vast majority of cultivars grown do not display significant resistance to PVY. Due to the short time period for PVY transmission by non-colonising aphid vectors, efficient control of PVY relies on preventing aphids landing on a crop and on adopting precautionary measures by ensuring that crops are grown in areas of low aphid and low virus pressure and limiting field generation. Prophylactic measures such as roguing and early haulm destruction limit PVY spread but are not efficient alone. Among all existing control methods, spraying potato crops with mineral oils can offer significant protection against PVY spread, but their efficacy do vary in field conditions. The combination of several control methods such as mineral oil treatments, crop borders, intercropping, straw mulching or insecticide treatments can increase protection. These emphasise the importance of controlling virus through appropriate monitoring methods and crop management enforced by seed certification schemes through the use of ‘clean’ input seed and, when possible, the segregation of seed and ware crops to minimise the risk of virus transmission. This chapter presents and discusses the most widely used techniques of control and management of PVY, their effectiveness and their mode of action. This chapter also presents the history, objectives and principles of seed potato certification schemes and their role in minimising the spread of viruses within potato crops worldwide