Bulk Y sub(1)Ba sub(2)Cu sub(3)O sub(y) superconductors with KClO sub(3) or K sub(2)CO sub(3) additives were synthesized by a solid state reaction method. The influence of additives on the AC ...susceptibility, morphology and microstructure of samples with nominal compositions Y sub(1)Ba sub(2-x)K sub(x)Cu sub(3)O sub(y), Y sub(1)Ba sub(2)Cu sub(3.5-x)K sub(x)O sub(y), Y sub(1-0.2x)K sub(x)Cu sub(3)O sub(y), (x identical with 0.2) were investigated. Experimental results showed a promoting effect of the additives on the formation of 123 phase in air atmosphere. Only traces of potassium were observed in all samples after the final backing, but chlorine was remained in the material. The superconducting transition temperature for all KClO sub(3)-doped samples was found to be higher than that for K sub(2)CO sub(3)-doped and undoped Y sub(1)Ba sub(2)Cu sub(3)O sub(y) (YBCO). KClO sub(3)-doped Y sub(1)Ba sub(1.8)Cu sub(0.2)O sub(y) with T super(o) sub(c) super(nset) at 105 K was obtained. The comparison of characteristics for samples with various potassium compound in the initial batch demonstrated that each additive had a specific effect on Chi (T), Delta T sub(c) and microstructure of YBCO high-temperature superconductors (HTSC). The results were discussed in terms of different interaction in which KClO sub(3) and K sub(2)CO sub(3) participate up to 900 degree C.
The lifetimes of the $2^+_1$, the $2^+_2$ and the $3^-_1$ states of
$^{210}$Po have been measured in the $^{208}$Pb($^{12}$C,$^{10}$Be)$^{210}$Po
transfer reaction by the Doppler-shift attenuation ...method. The results for the
lifetime of the $2^+_1$ state is about three times shorter than the adopted
value. However, the new value still does not allow for consistent description
of the properties of the yrast $2^+_1$, $4^+_1$, $6^+_1$, and $8^+_1$ states of
$^{210}$Po in the framework of nuclear shell models. The Quasi-particle Phonon
Model (QPM) calculations also cannot overcome this problem thus indicating the
existence of a peculiarity which is neglected in both theoretical approaches.
The market of organic products in Bulgaria enlarged significantly in the last few years. Although the shareof organic food products in general food market in the country is relatively small-less than ...5 %, the total area underorganic products in Bulgaria/cultivated and wild collected/ is more than 250 thousand ha. The development oforganic production is considered for one of the priority for development of the agricultural sector and food market.One of the factors considered to an obstacle for development of organic farming are the problems in the supply chainof organic products. The paper will provide a comprehensive overview of current status and prospects fordevelopment of organic food chain. It will be based on a research utilized the primary data collected through survey,based on in-dept interviews with a sample of stakeholders involved in organic food supply chain.The paper will covers the issues of current level of organic food supply chain, it will identifies problems in the supplychain, influence of supply chain on safety and quality of organic products. Particular emphasis will be given tooutline the different dimension of factors for successful marketing of organic products and measures for creating ofefficient supply chain of organic products in Bulgaria.Interesting conclusion can be drawn for the general food supply chain from the analyzing the expert opinions for theproper outlets for sales of organic products.
The market of organic products in Bulgaria enlarged significantly in the last few years. Although the share
of organic food products in general food market in the country is relatively small-less ...than 5 %, the total area under
organic products in Bulgaria/cultivated and wild collected/ is more than 250 thousand ha. The development of
organic production is considered for one of the priority for development of the agricultural sector and food market.
One of the factors considered to an obstacle for development of organic farming are the problems in the supply chain
of organic products. The paper will provide a comprehensive overview of current status and prospects for
development of organic food chain. It will be based on a research utilized the primary data collected through survey,
based on in-dept interviews with a sample of stakeholders involved in organic food supply chain.
The paper will covers the issues of current level of organic food supply chain, it will identifies problems in the supply
chain, influence of supply chain on safety and quality of organic products. Particular emphasis will be given to
outline the different dimension of factors for successful marketing of organic products and measures for creating of
efficient supply chain of organic products in Bulgaria.
Interesting conclusion can be drawn for the general food supply chain from the analyzing the expert opinions for the
proper outlets for sales of organic products.
In order to build reliable and robust structures for the future power supply, flexibilities of electrical generation, consumption and storage have to be increased. Within Dual Demand Side Management, ...the feasibility of a city quarter to manage locally its energy supply and to stabilize the regional grid is investigated. The concept focuses on the potential thermal storage systems provided by the existing building stock and on heat pumps as well as combined heat and power systems as generation and flexible storage units. Further, the physical building model and the distribution grid model will be coupled to a multi-energy simulation platform, to investigate the energy management options and the load shifting potential. In this paper we present the challenges met in process of system modeling. The chosen approaches are presented in two main sections, modeling and simulation requirements, together with discussed alternative solutions, drawbacks and limitations. The section Modeling deals with the user model and electricity demand forecasting, the building and electrical models. Main issues in the development of the building model concern the lack of available information of residents' behavior and building characteristics for its parameterization. Computational issues regarding the multi-energy simulation platform are discussed separately for the model coupling, the electrical and thermal simulation in the section Simulation Requirements.
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