133 resultados para AK43-4834


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Sediment samples were taken from Lake Langans in Sweden and fossilised diatoms analysed. Sample methods and environmental factors are discussed. Species with a characteristic occurrence are described. The article discusses diatom-thanatocoenoses as indicators of environment.

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Esta pesquisa aborda a aplicação da Teoria da Agência, a relação estabelecida entre as agências reguladoras e as entidades que exploram os serviços públicos sob sua tutela. A Teoria baseia-se na premissa de que a existência de separação entre a titularidade (propriedade) e o controle conduz à existência de conflitos de interesses entre as partes, e que uma das formas de se evitar esses conflitos é o estabelecimento de controles. Assim, haja vista a prerrogativa conferida pela lei a tais entidades, procurou-se verificar neste estudo o grau de regulação contábil empregado pelas agências reguladoras federais no desempenho de suas atribuições legais, que perpassam o controle de atividades econômicas específicas. Realizou-se estudo de casos de natureza exploratória em que se utilizou a fonte primária dos poderes das agências, a lei e os instrumentos de delegação de serviços públicos, visando verificar as características do sistema de controle por elas estabelecido. Os resultados obtidos apontam enormes distorções qualitativas e quantitativas na forma como as agências utilizam a informação contábil enquanto instrumento de controle. As contribuições desse estudo alcançam não apenas a comunidade científica e as agências, mas toda a sociedade, haja vista que as decisões das agências impactam diretamente o bem estar de toda a coletividade, sem exceções. Para a comunidade contábil, especialmente, o estudo aponta para um novo, pujante e praticamente inexplorado mercado de trabalho: a contabilidade regulatória.

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本文采用XAD-2和XAD-8(1:1)混合树脂现场富集采样,循环提取器提取,毛细管GC/MS定性的方法,通过对冬夏两季的采样分析,初步分析了某地自来(饮用)水中非挥发性有机氯化产物。从夏天自来水中检测出了28种有机氯化合物。从冬天自来水中只检出了1种有机氯化合物。

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Treatment of yttrium tris(alkyl)s, Y(CH2SiMe3)(3)(THF)(2), by equimolar H(C5Me4)SiMe3(HCp') and indene (Ind-H) afforded (eta(5)-Cp')Y(CH2SiMe3)(2)(THF) (1) and (eta(5)-Ind)Y(CH2SiMe3)(2)(THF) (2) via alkane elimination, respectively. Complex 1 reacted with methoxyamino phenols, 4,6-(CH3)(2)-2-[(MeOCH2CH2)(2)-NCH2]-C6H2-OH (HL1) and 4,6-(CMe3)(2)-2-[(MeOCH2CH2)(2)-NCH2]-C6H2OH (HL2) gave mixed ligands supported alkyl complexes [(eta(5)-Cp')(L)]Y(CH2SiMe3) (3: L = L-1; 4: L = L-2). Whilst, complex 2 was treated with HL2 to yield [(eta(5)-Ind)(L-2)]Y(CH2SiMe3) (5). The molecular structures of 3 and 5 were confirmed by X-ray diffraction to be mono(alkyl)s of THF-free, adopting pyramidal and tetragonal-bipyramidal geometry, respectively. Complexes 3 and 5 were high active initiators for the ring-opening polymerization Of L-lactide to give isotactic polylactide with high molecular weight and narrow to moderate polydispersity.

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Adsorption of a monolayer of didecanoyl-L-alpha-phosphatidylcholine (DDPC) from dispersions of small unilamellar vesicles onto hydrophobic surfaces was investigated by mean of cyclic voltammetry and impedance spectroscopy. The hydrophobic surfaces were self-assembled monolayers of 2-mereapto-3-n-octylthiophene (MOT) on gold. One characteristic of the MOT monolayer is its permeability to organic molecules in aqueous solution, thus providing a more energetically favorable hydrophobic surface for the addition of phospholipid vesicles. The kinetics of the lipid monolayer formation were followed by measuring the time-dependent interfacial capacitance. Unusual values of thickness and capacitance of the MOT/ DDPC bilayers were observed. An interdigitating conformation of the bilayer structure was proposed to interpret the experimental results, The horseradish peroxidase reconstituted into the bilayer demonstrated the expected protein activity, showing practical use in research and in biosensor application.

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The performance of an air-cycle refrigeration unit for road transport, which had been previously reported, was analysed in detail and compared with the original design model and an equivalent Thermo King SL200 vapour-cycle refrigeration unit. Poor heat exchanger performance was found to be the major contributor to low coefficient of performance values. Using state-of-the-art, but achievable performance levels for turbomachinery and heat exchangers, the performance of an optimised air-cycle refrigeration unit for the same application was predicted. The power requirement of the optimised air-cycle unit was 7% greater than the equivalent vapour-cycle unit at full-load operation. However, at part-load operation the air-cycle unit was estimated to absorb 35% less power than the vapour-cycle unit. The analysis demonstrated that the air-cycle system could potentially match the overall fuel consumption of the vapour-cycle transport refrigeration unit, while delivering the benefit of a completely refrigerant free system.

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Let $X$ be a real Banach space, $\omega:[0,+\infty)\to\R$ be an increasing continuous function such that $\omega(0)=0$ and $\omega(t+s)\leq\omega(t)+\omega(s)$ for all $t,s\in[0,+\infty)$. By the Osgood theorem, if $\int_{0}^1\frac{dt}{\omega(t)}=\infty$, then for any $(t_0,x_0)\in R\times X$ and any continuous map $f: R\times X\to X$ and such that $\|f(t,x)-f(t,y)\|\leq\omega(\|x-y\|)$ for all $t\in R$, $x,y\in X$, the Cauchy problem $\dot x(t)=f(t,x(t))$, $(t_0)=x_0$ has a unique solution in a neighborhood of $t_0$ . We prove that if $X$ has a complemented subspace with an unconditional Schauder basis and $\int_{0}^1\frac{dt}{\omega(t)}