122 resultados para AK44-4962


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Geological, mineralogical and microbiological aspects of the methane cycle in water and sediments of different areas in the oceans are under consideration in the monograph. Original and published estimations of formation- and oxidation rates of methane with use of radioisotope and isotopic methods are given. The role of aerobic and anaerobic microbial oxidation of methane in production of organic matter and in formation of authigenic carbonates is considered. Particular attention is paid to processes of methane transformation in areas of its intensive input to the water column from deep-sea hydrothermal sources, mud volcanoes, and cold methane seeps.

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An elevated particle number concentration (PNC) observed during nucleation events could play a significant contribution to the total particle load and therefore to the air pollution in the urban environments. Therefore, a field measurement study of PNC was commenced to investigate the temporal and spatial variations of PNC within the urban airshed of Brisbane, Australia. PNC was monitored at urban (QUT), roadside (WOO) and semi-urban (ROC) areas around the Brisbane region during 2009. During the morning traffic peak period, the highest relative fraction of PNC reached about 5% at QUT and WOO on weekdays. PNC peaks were observed around noon, which correlated with the highest solar radiation levels at all three stations, thus suggesting that high PNC levels were likely to be associated with new particle formation caused by photochemical reactions. Wind rose plots showed relatively higher PNC for the NE direction, which was associated with industrial pollution, accounting for 12%, 9% and 14% of overall PNC at QUT, WOO and ROC, respectively. Although there was no significant correlation between PNC at each station, the variation of PNC was well correlated among three stations during regional nucleation events. In addition, PNC at ROC was significantly influenced by upwind urban pollution during the nucleation burst events, with the average enrichment factor of 15.4. This study provides an insight into the influence of regional nucleation events on PNC in the Brisbane region and it the first study to quantify the effect of urban pollution on semi-urban PNC through the nucleation events. © 2012 Author(s).

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A Journey in the Landscape of Sustainable School Development “A Journey in the Landscape of Sustainable School Development” is a story of the Sorrila School development process. This research deals with a school development project as a process, and as a part of international projects on Education for Sustainable Development, with ENSI (Environment and School Initiatives) being the most important. The main purpose of the study was to analyze the change process as a general phenomenon as well as the learning connected to it. The research describes the development period 2001–2008 at the Sorrila Primary school. The research questions are as follows: 1. What did pupils learn during the research and development period? 2. How did the coordinating teacher develop personally? 3. How were the ENSI targets and other closely linked projects reached? 4. What was the feedback from the pupils, their parents and other teachers at the school? 5. How did the developing process proceed in 2001–2008? The method used was integrating action research, which also had ethnographical elements. Narrative was the form of the data as well as the manner of reporting. The method as a whole was integrating, ethnographical action research as a story. The research data consisted mostly of Knowledge Forum notes written by the teacher-researcher. Knowledge Forum is an Internetbased collaborative knowledge-building programme. Pupils’, parents’ and other teachers’ feedback, newspaper articles and students’ writings complied the data, which consists of material from seven years. Sustainable development was the basis of the school improvement. The targets of the United Nations Decade of Education for Sustainable Development (2005–2014) were part of the development projects. According to the research results the school was seen as part of complex systems where manifold and interactive learning took place. The learning of pupils, teachers and the school as a community can be characterised socioculturally. The school was able to reach a level of collaborative transformative learning. As well as several concrete projects, such as Comenius school project, school development consisted of networking at many levels. Along with the projects and networking, the school was able to apply the pedagogy of connection, by carrying out integrative and cross-disciplinary themes and using various learning and teaching methods. International cooperation was a natural part of the work. A figure of Aunt Green, the role model of the teacher researcher, was an innovation which resembled a change agent. The other role of the teacherresearcher as a coordinator, was important for her own professional development. According to the results the change process, which relied on sustainable school development, led the school along a road of positive renewals. It was not a series of projects but an ongoing process. The objectives of the international projects were accomplished to a great extent during the research period. According to the principles of action research, the main results were put forward in order to help others to develop their schools. Frictions and problems as well as positive experiences and rejecting dualities were seen as change forces. Keywords: education for sustainable development (ESD), sustainable school development, teacher professional development, integrating, pedagogy of connection, transformative learning

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Invasive grasses are among the worst threats to native biodiversity, but the mechanisms causing negative effects are poorly understood. To investigate the impact of an invasive grass on reptiles, we compared the reptile assemblages that used native kangaroo grass (Themeda triandra), and black spear grass (Heteropogon contortus), to those using habitats invaded by grader grass (Themeda quadrivalvis). There were significantly more reptile species, in greater abundances, in native kangaroo and black spear grass than in invasive grader grass. To understand the sources of negative responses of reptile assemblages to the weed, we compared habitat characteristics, temperatures within grass clumps, food availability and predator abundance among these three grass habitats. Environmental temperatures in grass, invertebrate food availability, and avian predator abundances did not differ among the habitats, and there were fewer reptiles that fed on other reptiles in the invaded than in the native grass sites. Thus, native grass sites did not provide better available thermal environments within the grass, food, or opportunities for predator avoidance. We suggest that habitat structure was the critical factor driving weed avoidance by reptiles in this system, and recommend that the maintenance of heterogeneous habitat structure, including clumping native grasses, with interspersed bare ground, and leaf litter are critical to reptile biodiversity.

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In our effort to explore the use of the sulfite ion to design hybrid and open-framework materials, we have been able to prepare, under hydrothermal conditions, zero-dimensional [Zn(C12H8N2)(SO3)]center dot 2H(2)O, I (a = 7.5737(5) angstrom, b = 10.3969(6) angstrom, c = 10.3986(6) angstrom, alpha = 64.172(1)degrees, beta = 69.395(1)degrees, gamma = 79.333(1)degrees, Z = 2, and space group P (1) over bar), one-dimensional [Zn-2(C12H8N2)(SO3)(2)(H2O)], II (a = 8.0247(3) angstrom, b = 9.4962(3) angstrom, c = 10.2740(2) A, alpha = 81.070(1)degrees, beta = 80.438(1)degrees, gamma = 75.66(5)degrees, Z = 2, and space group P (1) over bar), two-dimensional [Zn-2(C10H8N2)(SO3)(2)]center dot H2O, III (a = 16.6062(1) angstrom, b = 4.7935(1) angstrom, c = 19.2721(5) angstrom, beta = 100.674(2)degrees, Z = 4, and space group C2/c), and three-dimensional [Zn-4(C6H12N2)(SO3)(4)(H2O)(4)], IV (a = 11.0793(3) angstrom, c = 8.8246(3) angstrom, Z = 2, and space group P42nm), of which the last three are coordination polymers. A hybrid open-framework sulfite-sulfate of the composition [C2H10N2][Nd(SO3)(SO4)(H2O)](2), V (a = 9.0880(3) angstrom, b = 6.9429(2) angstrom, c = 13.0805(5) A, beta = 91.551(2)degrees, Z = 2, and space group P2(1)/c), with a layered structure containing metal-oxygen-metal bonds has also been described.

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Using spatially averaged global model, we succeed in obtaining some plasma parameters for a low pressure inductively coupled plasma source of our laboratory. As far as the global balance is concerned, the models can give reasonable results of the parameters, such as the global electron temperature and the ion impacting energy, etc. It is found that the ion flow is hardly affected by the neutral gas pressure. Finally, the magnetic effects are calculated by means of the method. The magnetic field can play an important role to increase plasma density and ion current.

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To be able to carry out physical, chemical and biological investigations on a lake, one needs a thorough knowledge of the volume of water and the shape of the lake basin. Little is known about the about the morphology of the lakes in Schleswig-Holstein and its ecological consequences. For this research a 30 KHz echo sounder with sediment transceiver was used to carry out profile determinations (echo soundings). This apparatus continuously records on paper the different reflexions and absorptions of the sediment and water body in the corresponding depth. By this, acoustically noticeable layers and different densities in the sediment and 'scattering layers' in the water body due to physical, chemical and biological reasons (e.g. plans and single fish) are made visible. Result are summarised here regarding the echo soundings in Blunker See.

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O projeto Intimidades possui dois desdobramentos: um prático, que corresponde a um filme de cinquenta e cinco minutos, e um teórico, que é representado pelo presente texto. O filme pretende ouvir as pessoas que realizam trabalhos considerados desprezíveis na nossa sociedade: são os homens e mulheres do labor, nossos pequenos escravos assalariados. Tendo este objetivo, buscou-se encontrar uma forma plástica (estética) para o filme que conseguisse escapar às determinações do poder, que são representadas pela televisão e pelo cinema comercial. Para tanto, recorreu-se a conceitos e ideias desenvolvidas pelo filósofo Gilles Deleuze e pelo teórico do cinema André Bazin. Conceitos como o de intercessores, de potências do falso, de falência do esquema sensório-motor, de plano centrífugo e de plano sequência foram articulados no presente texto e serviram como base teórica para se encontrar a forma do filme. Neste movimento entre a teoria e a prática, o projeto Intimidades colocou o pensamento da filosofia em contato com o campo extra-filosófico da arte, através do exemplo prático do filme

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本文综述了湖泊生态系统中的生物多样性问题。导致湖泊生态系统中的生物多样性下降的主要原因有:(1)河流冲刷淤积和围湖造田造成的湖泊生态系统的萎缩、碎裂;(2)江湖阻隔对江湖复合生态系统的破坏;(3)过度捕杀导致鱼类种类多样性的下降及优势鱼类的小型化;(4)水草顶级群落消失带来的次生性灭绝;(5)城郊湖泊加速富营养化造成的生境污染。

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中国科学院半导体研究所成立40年了,40年来全所几代人辛勤工作,从无到有,为开创和发展我国半导体科学,为建立我国半导体工业的初步基础以及将半导体技术应用于国防军工作出了重大贡献。作为我国第一代半导体材料科学研究人员,为此而感到欣慰。追忆四十多年的峥嵘岁月,我感到最值得珍惜的是当今艰苦奋斗的创业精神。在庆祝半导体研究所四十周年生日的时候,写出这篇短文与老同志们一起回味共同经历过的甘苦;希望年青的同志们将这种精神发扬光大,让半导体研究所对国家作出更大贡献。