Characterization of Fullerenes Obtained from Boron Nitrite Containing Graphite Electrodes: Electronic Structure of C60-X-YBXNY and Deformed C60

Abstract

The electronic structure of C₆₀ molecules with carbon substituted by other elements such as boron or nitrogen has been calculated for molecules in the singlet state with even number of electrons. Therefore, in the case of boron and nitrogen substituents, calculations have been performed for ionized molecules. The results obtained from our density functional calculations prove than in the C_60-x-yB_xN_y molecules both HOMO and LUMO levels are split due to the lower symmetry of the molecule Influence of deformation of C₆₀ molecules on electronic states, which is interesting because fullerenes may undergo deformation in solvate crystals, is also shown These C₅₉B and C₅₉N, as well as C₅₈BN molecules are of special interest because samples containing such species can be prepared The Electron Spin Resonance (ESR) in those samples differs from the results obtained in pure C₆₀ samples, it consists of several lines which are very sensitive to the temperature.     

Agricultural biogas plants in Poland: Investment process,economical and environmental aspects,biogas potential

The formal and legal requirements as well as the support system for building agricultural biogas plants in Poland have been presented. There are currently 24 agricultural biogas plants operating in Poland. The fermentation substrates are slurry, food waste and maize silage. It is most often mesophilic fermentation. Produced biogas is combusted in cogeneration and thus obtained electrical and thermal energy is used for the biogas plant's own needs and sold. The support system for biogas plants' operation in Poland is based on a system of certificates. In this system it is cost-effective to use waste for fermentation whilst it is not cost-effective for a biogas plant to run on maize silage. It has been calculated that in Poland the theoretical annual biogas potential for cattle slurry is 3646 million m³, for pig slurry it is 2581 million m³, for poultry manure it is 717 million m³, from maize after seed harvest it is 1044 million m³, from municipal waste biofraction it is 100 million m³ of biogas.     

Giant magnetostriction and flux jumps in superconducting Nb3Al polycrystalline slab

Transverse and longitudinal magnetostriction of a large polycrystalline slab of Nb₃Al superconductor was investigated by the strain gauge technique. At 4.2 K and in an external magnetic field of several Tesla the vertical width of transverse magnetostriction hysteresis loop was found to be of an order of 10⁻⁴. In a wide range of temperatures and external magnetic fields we observed the phenomenon of giant jumps of both transverse and longitudinal magnetostriction caused by thermomagnetic avalanches. The shapes of the magnetostriction hysteresis loops are also influenced by the phenomenon of the second maximum of the critical current density, called as a peak or fishtail effect. Experimental results can be understood in the framework of the model of the magnetostriction induced by pinning forces.     

The Peculiarities of Magnetic Flux Dynamics at Magnetothermal Instability in Textured Bi2Sr2CaCu2O8+δ

The magnetic flux dynamics was investigated in a textured Bi₂Sr₂CaCu₂O₈₊ sample using a miniature Hall probe placed on the surface of the superconductor. The process of magnetic flux penetration into the superconductor was found to have a complex structure and consist of two processes with different time scales. The first one has a length of tens of microseconds and is considered as locally adiabatic. The second one has a length comparable with the time of thermal diffusion. The importance of the above two processes in the development of magnetic instability is analyzed.     

Hyperuricaemia as an index of the response to chemotherapy in solid tumors

A transient increase in uric acid level following administration of high doses of Cyclophosphamide in the 1st course of cytostatic therapy applied for various solid tumors (mostly lung cancer) was observed in 10 patients with measurable disease simultaneously with complete or partial (above 50%) regression of the tumor. The same effect was noted in further 5 patients, who, however, had non-measurable disease. On the other hand, the clinical course of the disease and survival were similar in these 5 patients and in the former 10 patients. No corresponding increase in the uric acid level was observed in 87 patients with similar disease and treatment, but not responding to chemotherapy and with short survival. It is concluded, that hyperuricaemia may indicate responsiveness to chemotherapy in cancer patients with non-measurable disease.     

Can energy self-sufficiency be achieved? Case study of Warmińsko-Mazurskie Voivodeship (Poland)

Clean Technologies and Environmental Policy - An analysis was carried out to show whether the Warmińsko-Mazurskie Voivodeship (Poland) could become energy self-sufficient. The technical...