933 resultados para Third generation photovoltaics
Resumo:
Hong Kong was once a British colony and has been under the sovereignty of People’s Republic of China (PRC) since 1997. However, some of the unjust practices and colonial legacies are infiltrated into the development ideology as well as the social structures. The construction of intercity express railway project announced in 2008 causing the demolishment of Tsoi Yuen Tsuen, a “non-indigenous” agricultural village in Hong Kong, was one of the current examples. Tsoi Yuen village was established under the former colonial sovereignty sixty years ago. Approximately 450 populations were affected that they had to relocate their homeland involuntarily. However, these villagers were very attached to their homelands and were unwilling to move, and meanwhile they found that they were absent in the government’s consultation and decision-making process. Soon they began their resistance and demanded for “No Move! No Demolish!”. Their movement was strongly supported by a group of “Post-80s generation” and turned into the most important social movement of the city in recent years. In fact, demolition of Tsoi Yuen Village for city development is not an isolated case in the city. Meanwhile the situation is getting worse in Mainland China. I chose the case study of Tsoi Yuen Resistance from 2008 to 2011 for revelation of the complicated colonial history and postcolonial era of Hong Kong. I focused on discussing the Tsoi Yuen Resistance and the Post-80s movement, and how they have exposed the tension between top-down urban planning and development and public movements fighting for a more democratic process in choosing their way of living. Through the study of a village movement which as well as the rationale behind the Post-80s’ support, I hoped to illustrate how this movement has awaken a different sense of living for the new generations in the midst of the high-sounding urban development. It is an opportunity to examine Hong Kong’s colonial epoch in a different perspective: through studying the Tsoi Yuen Village, let them (subalterns) speak for themselves. Furthermore, the significance of this resistance, taking place eleven years after the handover to the PRC, is an important fact that I shall not miss in later discussion. Last but not least, during the resistance, advanced technology and social networks such as Facebook, Twitter, iPhone were used by Post 80s generation to spread the latest information in order to attract public’s concern and participation. Therefore, apart from studying Tsoi Yuen Resistance as a local social movement, I also regard it as a part of the global movement in perusing ecological lifestyle and civil society. How Post 80s’ generation manipulates the global idea in a local context will also be examined.
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The in situ cryo-crystallization study of benzyl derivatives reveals that the molecular packing in these compounds is either through methylene (sp(3)) C-H center dot center dot center dot pi or aromatic (sp(2)) C-H center dot center dot center dot pi interactions depending on the level of acidity of the benzyl proton. These studies of low melting compounds bring out the subtle features of such weak interactions and point to the directional preferences depending on the nature (electron withdrawing, polarizability) of the neighbouring functional group.
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A third polymorph of phenylacetylene (Z' = 6), which is obtained by quenching the liquid, shows some similarities to the two earlier known forms, and the adoption of a high Z' value in this crystal form is discussed.
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The critical, and often most difficult, step in structure elucidation of diverse classes of natural peptides is the determination of correct disulfide pairing between multiple cysteine residues. Here, we present a direct mass spectrometric analytical methodology for the determination of disulfide pairing. Protonated peptides, having multiple disulfide bonds, fragmented under collision induced dissociation (CID) conditions and preferentially cleave along the peptide backbone, with occasional disulfide fragmentation either by C-beta-S bond cleavage through H-alpha abstraction to yield dehydroalanine and cysteinepersulfide, or by S-S bond cleavage through H-beta abstraction to yield the thioaldehyde and cysteine. Further fragmentation of the initial set of product ions (MSn) yields third and fourth generation fragment ions, permitting a distinction between the various possible disulfide bonded structures. This approach is illustrated by establishing cysteine pairing patterns in five conotoxins containing two disulfide bonds. The methodology is extended to the Conus araneosus peptides An 446 and Ar1430, two 14 residue sequences containing 3 disulfide bonds. A distinction between 15 possible disulfide pairing schemes becomes possible using direct mass spectral fragmentation of the native peptides together with fragmentation of enzymatically nicked peptides.
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In this paper a new method is presented for generating earthquake accelerograms which have pre-established response spectra. The non-stationary random nature and other salient features of the accelerograms can be taken care of by the procedure developed. The method leads to a sample spectrum which lies above the given spectrum. The generation of records to suit several spectra simultaneously can also be handled by this approach. The method is detailed first. This is followed by several numerical examples.
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Head-on infall of two compact objects with arbitrary mass ratio is investigated using the multipolar post-Minkowskian approximation method. At the third post-Newtonian order the energy flux, in addition to the instantaneous contributions, also includes hereditary contributions consisting of the gravitational-wave tails, tails-of-tails, and the tail-squared terms. The results are given both for infall from infinity and also for infall from a finite distance. These analytical expressions should be useful for the comparison with the high accuracy numerical relativity results within the limit in which post-Newtonian approximations are valid.
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We report the absorption spectra, oscillator strengths, ground state and excited state dipole moments, and molecular second order polarizability coefficients (βCT) due to donor—acceptor charge transfer in four trisubstituted ethylenes, namely 1,1-bisdimethylamino-2-nitroethylene, 1,1-bispyrolidino-2-nitroethylene, 1,1-bispiperidino-2-nitroethylene and 1,1-bismorpholino-2-nitroethylene. The results are compared with that of trans-N,N-dimethylamino-nitroethylene, which has a large βCT. The powder second harmonic generation (SHG) intensity of all these molecules is also measured and only 1,1-bispiperidino-2-nitroethylene is found to possess an efficiency of 20% of that of urea under the same conditions. The SHG efficiency of this compound and deficiency in the other molecules in the powdered state is discussed in terms of their arrangements in the unit cell. The crystal structure of the active molecule is also presented and the structure—property relationship is critically examined in all these molecules.
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Biological membranes are tightly linked to the evolution of life, because they provide a way to concentrate molecules into partially closed compartments. The dynamic shaping of cellular membranes is essential for many physiological processes, including cell morphogenesis, motility, cytokinesis, endocytosis, and secretion. It is therefore essential to understand the structure of the membrane and recognize the players that directly sculpt the membrane and enable it to adopt different shapes. The actin cytoskeleton provides the force to push eukaryotic plasma membrane in order to form different protrusions or/and invaginations. It has now became evident that actin directly co-operates with many membrane sculptors, including BAR domain proteins, in these important events. However, the molecular mechanisms behind BAR domain function and the differences between the members of this large protein family remain largely unresolved. In this thesis, the structure and functions of the I-BAR domain family members IRSp53 and MIM were thoroughly analyzed. By using several methods such as electron microscopy and systematic mutagenesis, we showed that these I-BAR domain proteins bind to PI(4,5)P2-rich membranes, generate negative membrane curvature and are involved in the formation of plasma membrane protrusions in cells e.g. filopodia. Importantly, we characterized a novel member of the BAR-domain superfamily which we named Pinkbar. We revealed that Pinkbar is specifically expressed in kidney and epithelial cells, and it localizes to Rab13-positive vesicles in intestinal epithelial cells. Remarkably, we learned that the I-BAR domain of Pinkbar does not generate membrane curvature but instead stabilizes planar membranes. Based on structural, mutagenesis and biochemical work we present a model for the mechanism of the novel membrane deforming activity of Pinkbar. Collectively, this work describes the mechanism by which I-BAR domain proteins deform membranes and provides new information about the biological roles of these proteins. Intriguingly, this work also gives evidence that significant functional plasticity exists within the I-BAR domain family. I-BAR proteins can either generate negative membrane curvature or stabilize planar membrane sheets, depending on the specific structural properties of their I-BAR domains. The results presented in this thesis expand our knowledge on membrane sculpting mechanisms and shows for the first time how flat membranes can be generated in cells.
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Pattern Cognition is looked at from the functional view point. The need for knowledge in synthesizing such patterns is explained and various aspects of knowledge-based pattern generation are highlighted. This approach to the generation of patterns is detailed with a concrete example.
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A real-time operational methodology has been developed for multipurpose reservoir operation for irrigation and hydropower generation with application to the Bhadra reservoir system in the state of Karnataka, India. The methodology consists of three phases of computer modelling. In the first phase, the optimal release policy for a given initial storage and inflow is determined using a stochastic dynamic programming (SDP) model. Streamflow forecasting using an adaptive AutoRegressive Integrated Moving Average (ARIMA) model constitutes the second phase. A real-time simulation model is developed in the third phase using the forecast inflows of phase 2 and the operating policy of phase 1. A comparison of the optimal monthly real-time operation with the historical operation demonstrates the relevance, applicability and the relative advantage of the proposed methodology.