197,743 research outputs found
Svoboda, K. - Suk, M. - Zeman, P.: Doručování v soudním řízení
No full textRecenze publikace - Svoboda, K. - Suk, M. - Zeman, P.: Doručování v soudním řízeníLinde, a.s., Praha 2009, 267 stra
Erratum to: Sub-gap defect density characterization of molybdenum oxide: An annealing study for solar cell applications (Nano Research, (2020), 13, 12, (3416-3424), 10.1007/s12274-020-3029-9)
No full textRef. [56] was unfortunately wrong, Instead of [56] Corless, R. M.; Gonnet, G. H.; Hare, D. E. G.; Jeffrey, D. J.; Knuth, D. E. On the Lambert W function. Adv. Comput. Math. 1996, 5, 329–359. It should be changed to Biswas, R. K.; Khan, P.; Mukherjee, S.; Mukhopadhyay, A. K.; Ghosh, J.; Muraleedharan, K. Study of short range structure of amorphous Silica from PDF using Ag radiation in laboratory XRD system, RAMAN and NEXAFS. J. Non. Cryst. Solids 2018, 488, 1–9. Some entries in Table 2 were unfortunately misprinted.Photovoltaic Materials and DevicesElectrical Sustainable Energ
Long-term outcomes ypN0
No full textA retrospective analysis of 195 rectal cancer patients without main pathological risk factor
Non-equilibrium Strain and Elastic Hysteresis in Static and Dynamic Experiments in Sandstones
No full textThe physical origin of hysteretic elasticity in consolidated granular media is still debated. We show that hysteresis in quasi-static experiments (slow loading/unloading cycles) and dynamic acoustoelastic testing (fast perturbation of the sample obtained by a propagating or standing wave) can be seen as a consequence of slow dynamics, which also induces elastic anisotropy due to nonlinearity. Both conditioning (i.e. the evolution of the elastic properties towards a non-equilibrium steady state when a load is applied) and relaxation (i.e. the slow recovery of the original elastic properties when the strain is reduced) are described as the consequence of a non-equilibrium strain generated in the material by the applied load. Experiments performed span over five orders of magnitude in strain (from 10-7 to 10-2) and we demonstrate the proposed model captures well the observed phenomenology in the full strain range considered
Non-equilibrium strain induces hysteresis and anisotropy in the quasi-static and dynamic elastic behavior of sandstones: Theory and experiments
No full textMaterials with grain contacts or partially closed cracks exhibit anomalous elastic behavior: hysteresis in quasi-static experiments and slow dynamics in fast dynamic ones. Albeit the behavior in the two cases (which correspond to very different strain ranges) appears different, it should stem from the same physics and thus could be modelled by a universal equation of state. We propose a modification of the standard acoustoelastic theory, introducing the concept of conditioning induced non-equilibrium strain, which allows to predict the evolution of elastic wave velocity in both quasi-static and dynamic ranges, including the velocity anisotropy induced by external uniaxial loading. %In the limit case of a dynamic experiment, the modulus derived from our approach is formally equivalent to the butterfly modulus, i.e. to the sum of classical nonlinear terms (proportional to strain power) plus a butterfly like hysteresis modulus
AMČR - samostatný nález M-202400061-N00138
No full textStav: 4Evideční číslo: 102/24Poznámka: Zlomek lučíku drobné spony mladší formy noricko-panonských výrazně členěných spon (Almgren 70/73 podle Zeman 2017). Rozměry 1,7 x 0,9 cm
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
Materials and Light Management for High-Efficiency Thin-Film Silicon Solar Cells
No full textDirect conversion of sunlight into electricity is one of the most promising approaches to provide sufficient renewable energy for humankind. Solar cells are such devices which can efficiently generate electricity from sunlight through the photovoltaic effect. Thin-film silicon solar cells, a type of photovoltaic (PV) devices which deploy the chemical-vapor-deposited hydrogenated amorphous silicon (a-Si:H) and nanocrystalline silicon (nc-Si:H) and their alloys as the absorber layers and doped layers, are one of the promising PV technologies. Compared to other PV technologies, thin-film silicon solar cells have several important advantages such as the use of abundant and non-toxic materials, low processing temperature, short energy payback time and mature large-area manufacturing techniques. Despite the many advantages, thin-film silicon (TF-Si) technology is suffering from the drop in the PV market share due to the relatively low efficiency compared to c-Si, CIGS, and CdTe solar cells. This thesis is devoted to the development of advanced materials and novel light-trapping structures to increase the power conversion efficiency of thin-film silicon solar cells. To achieve maximal light absorption in the absorber layers, implementation of light-trapping structures is crucial for thin-film silicon solar cells. The status of light-trapping techniques is briefly summarized in chapter 1, together with the background knowledge for thin-film silicon solar cells. To design an effective light-trapping scheme for solar cells, both the optical performance and the influence on the electrical performance of solar cells have to be considered. The light-trapping structure itself should not give additional parasitic absorption losses, or this loss should be minimized. The morphology of the light-trapping substrate should be suitable for the growth of high-quality materials. Meanwhile, absorption losses in the supporting layers such as front electrodes, doped layers, and back reflectors should be minimized. In chapter 2, the fabrication of plasmonic back reflectors (BRs) based on self-assembled Ag nanoparticles and their application in a-Si:H solar cells are presented. It has been experimentally demonstrated that the optimized plasmonic back reflector can provide light trapping performance comparable to state-of-the-art random textures, without obvious deterioration of open-circuit voltage (Voc) and/or fill factor (FF). This conclusion is based on the fair comparison with high performance n-i-p solar cells and state-of-the-art p-i-n solar cells deposited on Asahi-VU substrates. The combined optical and electrical design of plasmonic back reflectors follows in chapter 3. The design rules of plasmonic back reflectors based on self-assembled Ag nanoparticles are discussed in detail. The shape of Ag NPs, the thickness of ZnO:Al spacer layers, materials on top of Ag NPs, and nanoparticle size are crucial for the performance of plasmonic BRs. By following the design ruless, an 8.4% efficiency plasmonic a-Si:H solar cell has been achieved. The application of the plasmonic back reflector in low bandgap nc-Si:H solar cells is discussed in chapter 4. The light trapping performance in nc-Si:H solar cells is improved by using the plasmonic BRs with a broad angular scattering and low parasitic absorption loss through tuning the size of silver nanoparticles. The nc-Si:H solar cells deposited on the improved plasmonic BRs demonstrate a high photocurrent comparable to the one achieved by the state-of-the-art textured Ag/ZnO BR. The commonly observed deterioration of fill factor is avoided by using nc-SiOx:H as the n-layer for solar cells deposited on plasmonic BRs. In chapter 5, micro-textures on glass with large opening angles and smooth U-shape morphology are proposed and applied to nc-Si:H solar cells for the first time. The micro-textures can provide both efficient light trapping and suitable morphology for the growth of high-quality nc-Si:H materials under a high deposition rate. A higher Voc and FF can be achieved in reference to the cells using nano-textured substrates. For thick solar cells (i-layer thicker than 2 µm), high Voc and FF values are maintained. Particularly, the Voc only drops from 564 to 541 mV as solar cell thickness increases from 1 to 5 ?m. The use of micro-textures paves the road to develop multijunction solar cells with a higher efficiency as will be shown in chapter 7. High-efficiency multijunction thin-film silicon solar cells require both high Voc and high blue spectral response in the top a-Si:H cell. In chapter 6, the mixed-phase p-SiOx films are investigated and used as window layer in high Voc a-Si:H p-i-n solar cells. The use of p-SiOx as window layer results in a higher Voc and a better spectral response than the standard p-SiC based window layer. Consequently, a-Si:H solar cells with Voc >1 V and FF >70% have been obtained. A high initial efficiency of 14.4% has been achieved in a-Si:H/nc-Si:H tandem solar cells deposited on the Asahi-VU substrates. Chapter 7 presents the implementation of highly transparent modulated-surface-textured (MST) front electrodes as light-trapping structures in multijunction TF-Si solar cells. The MST substrates comprise a micro-textured glass as developed in chapter 5, a thin layer of hydrogenated indium oxide (IOH), and a sub-micron nano-textured ZnO layer grown by low-pressure chemical vapor deposition (LPCVD ZnO). The MST front electrode has a good transparency and conductance, can provide efficient light trapping for each subcell and a suitable morphology for the growth of high-quality silicon layers. Efficiencies of 14.8% (initial) and 12.5% (stable) have been achieved for a-Si:H/nc-Si:H tandem solar cells with the MST front electrode and the high-performance a-Si:H top cells as developed in chapter 6, surpassing efficiencies obtained on state-of-the-art LPCVD ZnO. A short summary of this thesis is given in chapter 8. Perspectives to further improve the performance of thin-film silicon solar cells are suggested and discussed. The light-trapping performance of modulated-surface-textured front electrodes can be further improved by replacing the wet-etched glass with honeycomb textures, without sacrifice in electrical performance of solar cells. The honeycomb textures can be easily applied to superstrate configuration by mature UV-NIL technique. In the end, the hybrid a-Si:H/organic multijunction device configuration is proposed to avoid the use of thick nc-Si:H solar cells. A high efficiency of 11.6% has been achieved in the hybrid tandem configuration with a total absorber layer thickness less than 500 nm. By deploying the triple-junction structure, a high efficiency of 13.2% has been obtained while the thickness of absorber layers stack is below 1µm. With further efforts on this concept, performance comparable to the traditional devices based on a-Si:H and nc-Si:H can be expected while the total processing time is much shorter and the cost for manufacturing and materials is lower.Electrical Sustainable EnergyElectrical Engineering, Mathematics and Computer Scienc
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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