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61.
Opto-electronic properties of rough LP-CVD ZnO:B for use as TCO in thin-film silicon solar cells 总被引:1,自引:0,他引:1
Sylvie Faÿ Jérôme Steinhauser Nuno Oliveira Evelyne Vallat-Sauvain Christophe Ballif 《Thin solid films》2007,515(24):8558-8561
Polycrystalline Boron-doped ZnO films deposited by low pressure chemical vapor deposition technique are developed for their use as transparent contacts for thin-film silicon solar cells. The size of the columnar grains that constitute the ZnO films is related to their light scattering capability, which has a direct influence on the current generation in thin-film silicon solar cells. Furthermore, if the doping level of the ZnO films is kept below 1 × 1020 cm− 3, the electron mobility can be drastically enhanced by growing large grains, and the free carrier absorption is reduced. All these considerations have been taken in account to develop ZnO films finely optimized for the fabrication of microcrystalline thin-film silicon solar cells. These TCO allow the achievement of solar cell conversion efficiencies close to 10%. 相似文献
62.
Due to their outstanding mechanical, thermal, and durability properties, polymer matrix nanocomposites (PMCs) are currently a prominent area of research. The opportunity of applying PMCs in structural reinforcement and rehabilitation of damaged infrastructures, as well as working as a new structural material, justifies the increasing number of recent studies. In this review article, the effect of adding different reinforcements at nano-scale, such as carbon nanotubes, nanoclay, graphene, or nanosilica to polymer matrices, is discussed and the improvement in mechanical properties of PMCs is evaluated. Some concluding remarks and new perspectives on the use of PMCs in structures are given. 相似文献
63.
Microglia Response and In Vivo Therapeutic Potential of Methylprednisolone‐Loaded Dendrimer Nanoparticles in Spinal Cord Injury 下载免费PDF全文
64.
Valentina Marchionni Nuno Lopes Luis Mamouros Dídia Covas 《Water Resources Management》2014,28(13):4415-4431
The aim of this paper is the establishment and validation of cost functions for the various assets of sewer systems, namely gravity and raising pipes, manholes and pumping-stations. Costs are defined as a function of the main physical characteristics of the assets, such as, the pipe material and diameter, excavation depth and percentage of pavement (for sewer pipes), the manhole depth (for manholes) and flow rate, pump head and pump power (for pumping stations,). A four-step methodology was followed: 1) data collection, processing and analysis, 2) present value calculation, 3) key parameters identification and cost functions estimation, and 4) cost functions validation. Cost and infrastructure data for construction contracts of sewer systems managed by Águas de Portugal (AdP) were analyzed. Cost functions were estimated based on multiple linear regression analysis and compared with the ones obtained in previous studies. 相似文献
65.
A proteomic analysis of green and white sturgeon larvae exposed to heat stress and selenium 总被引:1,自引:0,他引:1
Frédéric Silvestre Javier Linares-Casenave 《The Science of the total environment》2010,408(16):3176-3188
Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay/Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26 °C and micro-injected with Seleno-L-Methionine to reach 8 µg g−1 selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P < 0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65 kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons could indicate early warning signals preceding population decline. 相似文献
66.
S. Silvestre D. Bernard S. Mezi re E. Constant 《Materials Science and Engineering: B》2001,80(1-3):270-273
The results obtained, very recently, in n-type Si-doped GaAs passivated with a hydrogen (H) or deuterium (D) plasma, on the stability of the Si–H or Si–D complexes are summarized. It is shown that a strong dissociation of the Si–H or Si–D complexes, associated with a large isotope effect is observed when hot electrons are produced or externally injected (using an electron-beam) in Si-doped hydrogenated or deuterated GaAs. The application of these results to the reliability of III–V devices is studied. The role of hot electrons is described and the device lifetime improvement, which could be obtained by using suitable thermal annealings, is discussed. 相似文献
67.
The management of financial portfolios or funds constitutes a widely known problematic in financial markets which normally requires a rigorous analysis in order to select the most profitable assets. The presented paper proposes a new approach, based on Intelligent Computation, in particular genetic algorithms, which aims to manage a financial portfolio by using technical analysis indicators (EMA, HMA, ROC, RSI, MACD, TSI, OBV). In order to validate the developed solution an extensive evaluation was performed, comparing the designed strategy against the market itself and several other investment methodologies, such as Buy and Hold and a purely random strategy. The time span (2003–2009) employed to test the approach allowed the performance evaluation under distinct market conditions, culminating with the most recent financial crash. The results are promising since the approach clearly beats the remaining approaches during the recent market crash. 相似文献
68.
In this paper a classification system of the anomalies in ceramic tiling applied to building façades and their most probable causes is proposed and a field data analysis is presented.The field work included the observation of 85 ceramic tiling systems in façades via standardized inspections. A statistical analysis of the anomalies observed during these inspections and their most probable causes is presented and the main ceramic tiling anomalies are evaluated for area affected, user disturbance and most probable causes.The interpretation of this data allowed the creation of an inventory of the measures to be implemented in the design, execution and maintenance phases, in order to prevent the occurrence of anomalies, helping the practicing engineer in his daily activity. 相似文献
69.
70.
Carlos Sousa Nuno Mateus Artur M.S. Silva Ana M. González-Paramás Celestino Santos-Buelga Victor de Freitas 《Food chemistry》2007,102(4):1344-1351
A new pigment, resulting from the reaction between malvidin 3-glucoside and catechin in the presence of vanillin, was detected in a model solution. This newly formed anthocyanin-aryl-flavanol adduct was structurally characterized by 1D and 2D NMR and mass spectrometry, and its chromatic characteristics were studied by UV–Vis techniques. The new pigment was shown to have a wavelength of maximum absorption in the visible region (λmax) of 549 nm, conferring on it a purple colour, and a molar extinction coefficient value (ε) of 12,247 l · mol−1 · cm−1. 相似文献