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1.
Ligand‐Free Synthesis of Aluminum‐Doped Zinc Oxide Nanocrystals and their Use as Optical Spacers in Color‐Tuned Highly Efficient Organic Solar Cells 下载免费PDF全文
Meriem Gaceur Sadok Ben Dkhil David Duché Fatima Bencheikh Jean‐Jacques Simon Ludovic Escoubas Mahdi Mansour Antonio Guerrero Germà Garcia‐Belmonte Xianjie Liu Mats Fahlman Walid Dachraoui Abdou Karim Diallo Christine Videlot‐Ackermann Olivier Margeat Jörg Ackermann 《Advanced functional materials》2016,26(2):243-253
The color of polymer solar cells using an opaque electrode is given by the reflected light, which depends on the composition and thickness of each layer of the device. Metal‐oxide‐based optical spacers are intensively studied in polymer solar cells aiming to optimize the light absorption. However, the low conductivity of materials such as ZnO and TiO2 limits the thickness of such optical spacers to tenths of nanometers. A novel synthesis route of cluster‐free Al‐doped ZnO (AZO) nanocrystals (NCs) is presented for solution processing of highly conductive layers without the need of temperature annealing, including thick optical spacers on top of polymer blends. The processing of 80 nm thick optical spacers based on AZO nanocrystal solutions on top of 200 nm thick polymer blend layer is demonstrated leading to improved photocurrent density of 17% compared to solar cells using standard active layers of 90 nm in combination with thin ZnO‐based optical spacers. These AZO NCs also open new opportunities for the processing of high‐efficiency color tuned solar cells. For the first time, it is shown that applying solution‐processed thick optical spacer with polymer blends of different thicknesses can process solar cells of similar efficiency over 7% but of different colors. 相似文献
2.
The lateral heterogeneity of lipids in the thylakoid membrane has been questioned for over 20 yrs. It is generally believed
that glycerolipids are asymmetrically distributed within the plane of the membrane. In the present investigation, we isolated
several thylakoid membrane domains by using sonication followed by separation in an aqueous dextran-polyethylene glycol two-phase
system. This technique, which avoids detergent treatments, allowed us to obtain stroma and grana lamellae vesicles as well
as grana central core and grana margin vesicles from thylakoids. The relative distribution of the four lipid classes, i.e.,
monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyldiacylglycerol, and phosphatidylglycerol, was found
to be statistically identical in all four thylakoid fractions and in whole thylakoids. Similarly, the relative amount of fatty
acids in each individual lipid and the eight main phosphatidylglycerol molecular species was identical in all thylakoid membrane
fractions tested as well as in the intact thylakoid membrane. Based on presently available procedures for obtaining thylakoid
subfractions that are unable to discriminate microdomains within the membrane, it is concluded that glycerolipids are evenly
distributed within the plane of the thylakoid membrane. These data are discussed in terms of “bulk” and “specific” lipids. 相似文献
3.
Aleksandar Jovanović Aleksandar Perović Wlodzimierz Klonowski Wlodzisław Duch Zoran Đorđević Slađana Spasić 《Journal of Signal Processing Systems》2010,60(1):115-129
In this article structures in biological signals are treated. The simpler—directly visible in the signals, which still demand
serious methods and algorithms in the feature detection, similarity investigation and classification. The major actions in
this domain are of geometric, thus simpler sort, though there are still hard problems related to simple situations. The other
large class of less simple signals unsuitable for direct geometric or statistic approach, are signals with interesting frequency
components and behavior, those suitable for spectroscopic analysis. Semantics of spectroscopy, spectroscopic structures and
research demanded operations and transformations on spectra and time spectra are presented. The both classes of structures
and related analysis methods and tools share a large common set of algorithms, all of which aiming to the full automatization.
Some of the signal features present in the brain signal patterns are demonstrated, with the contexts relevant in BCI, brain
computer interfaces. Mathematical representations, invariants and complete characterization of structures in broad variety
of biological signals are in the central focus. 相似文献
4.
Hull cells are often used to determine the optimum current density range for industrial electroplating. However, these cells do not reproduce correctly the hydrodynamic conditions. The design and the use of a modified Hull cell able to reproduce constant hydrodynamic conditions at the cathode for a large range of circulation speeds are described. Mass transfer and current distribution at the cathode have been evaluated in this cell for copper and zinc deposition. 相似文献
5.
6.
The mechanism of synergy between 3'-azido-3'-deoxythymidine (AZT) and anticancer agents was investigated with emphasis on cell-cycle events. Exposure of exponentially growing WiDr human colon carcinoma cells to AZT resulted in synchronization of cells in the S phase of the cell cycle. Following treatment with AZT at 50 or 200 microM, 62% +/- 3% or 82% +/- 4% of the cells were in the S phase as compared with 36% +/- 2% in the control. Bromodeoxyuridine uptake studies revealed that the synchronized cells actively synthesized DNA. At concentrations of up to 200 microM, AZT produced a cytostatic rather than cytotoxic effect as indicated by viability and cell growth measurements. At 200 microM, AZT-induced synchronization was significant (P = < 0.001) after 12 h of drug exposure, reached a maximum at 24 h, and reversed to baseline levels by 72 h even in the continued presence of the drug. This indicates that AZT-induced cytostasis is a transient and reversible effect. The cell-cycle events seen with AZT in WiDr cells were also observed in eight of nine human tumor cell lines tested. Isobologram analysis of WiDr cells preexposed to AZT for 24 h and then exposed to either AZT-5-fluorouracil or AZT-methotrexate for a further 72 h revealed synergy between AZT and the anticancer agents, indicating that AZT-induced synchronization may have therapeutic benefits. 相似文献
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8.
Duch MA Carrasco P Ginjaume M Jornet N Ortega X Ribas M 《Radiation protection dosimetry》2006,120(1-4):43-47
In high-energy photon external radiotherapy treatment planning systems (TPSs) are used to calculate the dose to the target volume and the dose distribution around it. Commonly used TPSs include algorithms based on measurements in water and often fail in the estimate of dose in the presence of heterogeneities. In this study TL detectors were used to study the reliability of the Cadplan (Varian) TPS in the presence of low-density heterogeneities such as the lung for 6 and 18 MV photon beams at different field sizes. TL measurements were compared with TPS calculations and Monte Carlo simulations performed with the PENELOPE MC code. In a phantom with lung heterogeneity, TL measurements and MC simulations agreed, with an average deviation inside the lung of 2%. In contrast, TPS results overestimated the dose inside the lung, with a maximum deviation of 39% for the 18 MV photon beam and a field size of 2 x 2 cm(2). 相似文献
9.
10.
The effects of protein type and pattern size on cell adhesion, spreading, and focal adhesion development are studied. Fibronectin and vitronectin patterns from 0.1 to 3 μm produced by colloidal lithography reveal important differences in how cells adhere to and bridge focal adhesions across protein nanopatterns versus micropatterns. Vinculin and zyxin in focal adhesions but not integrins are seen to bridge ligand gaps. Differences in protein mechanical properties are implicated as important factors in focal adhesion development. 相似文献