Interest in thorium stems mainly from the fact that it is expected to have a substantial increase in uranium prices. So, advanced fuel cycles which increase the reserves of nuclear materials are interesting, particula...Interest in thorium stems mainly from the fact that it is expected to have a substantial increase in uranium prices. So, advanced fuel cycles which increase the reserves of nuclear materials are interesting, particularly, the use of thorium is to produce the fissile isotope ^233U. Thorium is three to five times more abundant than uranium in the earth＇s crust. Additionally, thoria produces less radiotoxicity than the UO2, because it produces fewer amounts of actinides. ThO2 has higher corrosion resistance, besides being chemically stable, and the burning of Pu in a reactor based in thorium also decreases the inventories of Pu from the current fuel cycles. There are some ongoing projects in the world, taking into consideration the proposed goals for Generation IV reactors, namely： sustainability, economics, safety and reliability, proliferation resistance and physical protection. Some developments on the use of thorium in reactors are underway, with the support of the IAEA （International Atomic Energy Agency） and some govern like molten salt reactor. In this paper, we discuss the future importance of thorium, particularly for Brazil, which has large mineral reserves of this strategic element, the characteristics of the molten salt reactor and the experience of the IPEN （Instituto de Pesquisas Energ6ticas e Nucleares） in the purification of thorium compounds.展开更多
Selection of suitable seed in agriculture has great importance in terms of scarce resources and efficient use of facilities. Efficient use of inputs has been one of the key objectives of agricultural policies in all o...Selection of suitable seed in agriculture has great importance in terms of scarce resources and efficient use of facilities. Efficient use of inputs has been one of the key objectives of agricultural policies in all over the world. Therefore, studies continue about production of new seeds with high yield and resist to diseases. The 66.7% of the total seed production in Turkey are met by the private sector （hybrid sunflower, corn, potato, soybean, cotton and vegetable seed）. And 53.4% of the total sunflowers in Turkey are grown in Thrace region. It is therefore appropriate to be selected as the research area. In this regard, the aim of this study was to examine the dynamics in seed sector and particularly investigate the sunflower seed purchasing behavior of farmers with special attention to Thrace region. As a methodology, 198 questionnaires which pursued sunflower farm activities in the region were utilized. As a result of the descriptive statistics, it could be concluded that almost 20% of seed supply in Turkey is imported and that 70%-80% of it is directly used as an “input” for growing vegetative products and the remaining is used as “intermediate goods” for growing “certified seeds” for domestic or international markets.展开更多
This paper aims at investigating the teletandem learning interactions between a group of Brazilian students from Instituto Federal de Educagao, Ciencia e Tecnologia do Estado de Goias, Brazil, and a group of foreign s...This paper aims at investigating the teletandem learning interactions between a group of Brazilian students from Instituto Federal de Educagao, Ciencia e Tecnologia do Estado de Goias, Brazil, and a group of foreign students from two German universities. In this study, the Brazilian students helped their foreign partners with Portuguese learning and were helped by them in the English learning. The participants used a synchronous computer software called Openmeetings and also an electronic dictionary as a complementary tool. Adopting a qualitative perspective in the data collection and analysis, this case study was conducted in the second semester of 2010. The data were collected by means of conversation sessions through Openmeetings and were analyzed in the light of studies on sociocultural theory as well as on tandem/teletandem language learning researches. The data analyses showed that the participants used English as an anchoring language to work with Portuguese and English itself, and German was introduced in the teletandem sessions. The data also showed that the whiteboard and the electronic dictionary were used as complementary resources to the use of audio and video for the language learning process the participants engaged in.展开更多
文摘Interest in thorium stems mainly from the fact that it is expected to have a substantial increase in uranium prices. So, advanced fuel cycles which increase the reserves of nuclear materials are interesting, particularly, the use of thorium is to produce the fissile isotope ^233U. Thorium is three to five times more abundant than uranium in the earth＇s crust. Additionally, thoria produces less radiotoxicity than the UO2, because it produces fewer amounts of actinides. ThO2 has higher corrosion resistance, besides being chemically stable, and the burning of Pu in a reactor based in thorium also decreases the inventories of Pu from the current fuel cycles. There are some ongoing projects in the world, taking into consideration the proposed goals for Generation IV reactors, namely： sustainability, economics, safety and reliability, proliferation resistance and physical protection. Some developments on the use of thorium in reactors are underway, with the support of the IAEA （International Atomic Energy Agency） and some govern like molten salt reactor. In this paper, we discuss the future importance of thorium, particularly for Brazil, which has large mineral reserves of this strategic element, the characteristics of the molten salt reactor and the experience of the IPEN （Instituto de Pesquisas Energ6ticas e Nucleares） in the purification of thorium compounds.
文摘Selection of suitable seed in agriculture has great importance in terms of scarce resources and efficient use of facilities. Efficient use of inputs has been one of the key objectives of agricultural policies in all over the world. Therefore, studies continue about production of new seeds with high yield and resist to diseases. The 66.7% of the total seed production in Turkey are met by the private sector （hybrid sunflower, corn, potato, soybean, cotton and vegetable seed）. And 53.4% of the total sunflowers in Turkey are grown in Thrace region. It is therefore appropriate to be selected as the research area. In this regard, the aim of this study was to examine the dynamics in seed sector and particularly investigate the sunflower seed purchasing behavior of farmers with special attention to Thrace region. As a methodology, 198 questionnaires which pursued sunflower farm activities in the region were utilized. As a result of the descriptive statistics, it could be concluded that almost 20% of seed supply in Turkey is imported and that 70%-80% of it is directly used as an “input” for growing vegetative products and the remaining is used as “intermediate goods” for growing “certified seeds” for domestic or international markets.
文摘This paper aims at investigating the teletandem learning interactions between a group of Brazilian students from Instituto Federal de Educagao, Ciencia e Tecnologia do Estado de Goias, Brazil, and a group of foreign students from two German universities. In this study, the Brazilian students helped their foreign partners with Portuguese learning and were helped by them in the English learning. The participants used a synchronous computer software called Openmeetings and also an electronic dictionary as a complementary tool. Adopting a qualitative perspective in the data collection and analysis, this case study was conducted in the second semester of 2010. The data were collected by means of conversation sessions through Openmeetings and were analyzed in the light of studies on sociocultural theory as well as on tandem/teletandem language learning researches. The data analyses showed that the participants used English as an anchoring language to work with Portuguese and English itself, and German was introduced in the teletandem sessions. The data also showed that the whiteboard and the electronic dictionary were used as complementary resources to the use of audio and video for the language learning process the participants engaged in.
