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51.
To estimate geometrically regular images in the white noise model and obtain an adaptive near asymptotic minimaxity result, we consider a model selection based bandlet estimator. This bandlet estimator combines the best basis selection behavior of the model selection and the approximation properties of the bandlet dictionary. We derive its near asymptotic minimaxity for geometrically regular images as an example of model selection with general dictionary of orthogonal bases. This paper is thus also a self-contained tutorial on model selection with orthogonal bases dictionary.  相似文献   
52.
The rheological behaviour of concentrated aqueous dispersions of unmodified (FBPI I) and acetylated (FBPI I) faba bean (Vicia faba L. minor) protein isolates are investigated within a pH range of 4.0 up to 7.5. Besides the fact that equal concentrated dispersions of FBPI I show a much lower apparent viscosity η than those prepared with FBPI II, η and the flow behaviour index n depend also on the kind of preparation. Especially the direction of pH shifting and the mode of pH adjustment lead to marked differences of the rheological properties. In the case of FBPI II dispersions a maximum of η and n is shown at pH 5.5 to 6.5, seldom at pH 7.0, probably connected with a maximum of the hydrodynamic volume. Holding the aqueous dispersions for 24h causes mostly an increase of η and n.  相似文献   
53.
La0.7Ba0.3MnO3 (LBMO) thin films with different thicknesses were deposited on Si substrates using an electron beam evaporation technique for bolometer applications. To evaluate the influence of the thickness on their structural, compositional, morphological, and electrical properties, the LBMO thin films were characterized by x-ray diffraction (XRD), energy-dispersive spectroscopy, atomic force microscopy, and a four-probe method. XRD measurements showed that the crystal quality of the LBMO films improved with increasing thickness. The surface morphology revealed that the grain size and surface roughness of the films increased with increasing thickness. The resistivity increased with increasing thickness of the film. The temperature coefficient of resistance of the LBMO films decreased from 5.15%/K to 4.12%/K with increase of the film thickness from 20 nm to 100 nm.  相似文献   
54.
CuGaSe2 (CGS) thin films were prepared on tin‐doped indium oxide (ITO) coated soda‐lime glass substrates by thermal co‐evaporation to fabricate transparent solar cells. The films consisted of columnar grains with a diameter of approximately 1 μm. Some deterioration of the transparency of the ITO was observed after deposition of the CGS film. The CGS solar cells were electrically connected in series with Cu(In,Ga)Se2 (CIGS) solar cells and mechanically stacked on the CIGS cells to construct tandem cells. The tandem solar cell with the CGS cell as the top cell showed an efficiency of 7.4% and an open‐circuit voltage of 1.18 V (AM 1.5, total area). Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
55.
Since internet access is used by billions of people worldwide and the number of internet user is also increasing every day, a new technology called as wireless mesh network (WMN) is becoming popular. This is because it has some desirable characteristic, but it has some limitation for multi-hop routing, bandwidth, and many more. In order to overcome these issues, we proposed Way-Point Multicast Routing Framework (WPMRF) for improving the quality of service (QoS) in Hybrid WMN. Initially, the multicast framework is established based on the minimum load factor. The route established with least load factor is considered, as it avoids any kind of congestion in the network. After that, segmentation of route is done, and the way-point nodes are selected to join the multicast session. After that, the transmission is performed using MAODV and ODMRP protocol. In addition, an estimated route disconnection parameter is used for fast route recovery process and helps to select more reliable route path. The advantage of the proposed work is that it provides more reliable routing path to increase the quality of service (QoS) with fast route recovery process.  相似文献   
56.
Successful interface engineering requires compositional and electronic material characterization as a prerequisite for understanding and intentionally generating interfaces in photovoltaic devices. The paper gives an overview with several examples, all referring to Cu(In,Ga)(S,Se)2 (“CIGSSe”)-based solar cells, with an emphasis on characterization using highly specialized methods, such as elastic recoil detection analysis, X-ray emission spectroscopy and photoelectron spectroscopy using synchrotron and ultraviolet light for excitation, inverse photoemission spectroscopy and Kelvin probe force microscopy. First, the determination of the depth profile of the band gap energy Eg in the absorber layer is demonstrated. The modification of Eg towards both interfaces is discussed in terms of beneficial electronic effects. Next, the interface between absorber and buffer layers with alternative and promising non-toxic materials is considered. Between CIGSSe and a ZnSe buffer deposited by the metalorganic chemical vapor deposition (MOCVD) method a buried ZnS interface was found. For a Zn(O,OH) buffer processed with an ion layer gas reaction (ILGAR) the correlation of surface composition, valence band maximum and efficiency of the resulting solar cell is shown. In addition, another approach is considered where a ZnMgO window layer is sputtered directly on the absorber omitting any buffer layer. The determination of the potential distribution at the ZnMgO/CIGSSe interface supports the understanding of this new and simpler way to get good cell performances even without any buffer. Finally, monolithically integrated solar modules without encapsulation were investigated before and after accelerated aging tests and changes at the interconnects were identified.  相似文献   
57.
Consumer studies and market reports show an increase in consumption of ready‐to‐eat (RTE) foods. Although conventional processing technologies can in most cases produce safe products, they can also lead to the degradation of nutritional compounds and negatively affect quality characteristics. Consumers strongly prefer food that is minimally processed with the maximum amount of health‐promoting substances. Novel processing technologies as pre‐ or post‐treatment decontamination methods or as substitutes of conventional technologies have the potential to produce foods that are safe, rich in nutrient content and with superior organoleptic properties. Combining novel with conventional processes can eliminate potential drawbacks of novel technologies. This review examines available scientific information and critically evaluates the suitability and efficiency of various novel thermal and nonthermal technologies in terms of microbial safety, quality as well as nutrient content on the production of RTE meals, meats and pumpable products.  相似文献   
58.
Solanum torvum fruit widely used in traditional medicine of India and also in food preparation. Three different extracts such as water (WE), methanol (ME), and ethanol (EE) were used to evaluate their antioxidant and radical scavenging activity by different methods. All the assays results were compared with well-known standard antioxidants. The IC(50) values of assays were determined. The total phenolic and flavonoids content were found to be maximum in water and ethanol extracts, respectively. The electron quenching ability of fruit extract was assayed by DPPH and reducing power assays succeeding order were ME > EE > WE, respectively. Inhibition of membrane damage, was assayed interns of oxidative hemolysis and lipid peroxidation assays, among all WE extract shows 58.00% and 68.55 5% percentage of inhibition with 0.9 and 0.8 correlations (r(2) ), respectively. Antioxidant and radical quenching efficiency were assayed by β-carotene bleaching and hydroxyl radical scavenging method and results were compared with vitamin C and catechin. The in vitro free radical quenching and antioxidant results were well correlated with in vitro DNA protection assay. As analyzed by HPTLC gallic acid content is high in WE (1394 ± 25.0) and ME (598 ± 54.0) whereas ferulic acid is high in EE (32 ± 5.94) μg/g, respectively. This study indicate that S. torvum fruit is an excellent source of natural antioxidant and could be an effective nutritional food supplement, which interns will have therapeutic applications. Practical Application: In siddha medicine on the traditional systems of India the, ripened fruits are used in the preparation of tonic named as a "sundaivattaral choornam" is used to improve the health and prevent several diseases. This study has given an experimental evidence that S. torvum fruit is an excellent source of natural antioxidants.  相似文献   
59.
The chemical composition of three essential oils obtained from the barks of three endemic Boswellia species namely, Boswellia dioscorides, Boswellia elongata and Boswellia socotrana which were collected from the Soqotra Island (Yemen), was investigated. In parallel to that evaluation of their antimicrobial and antioxidant activities was also carried out. The investigation led to the identification of 72, 70 and 67 constituents for B.dioscorides, B. elongata, and B. socotrana, respectively. The B. dioscorides oil was found to have a high content of monoterpene hydrocarbons (32.8%) with α-thujene (9.3%) and α-pinene (8.3%) as main components. Whereas, the essential oil of B. elongata was characterised by high diterpene content (31.7%), in which incensol (14.8%) was found to be the major constituent. On the other hand, the oil obtained from the B. socotrana was found to be predominated of monoterpene hydrocarbons (26.4%) and oxygenated monoterpenes (30.7%) with p-cymene (13.0%), 2-hydroxy-5-methoxy-acetophenone (16.3%) and camphor (11.6%). All essential oils possessed antimicrobial activity especially against Gram-positive bacteria with MIC-values between 1.8 and 17.2 mg/ml. Furthermore, the DPPH-radical scavenging assay exhibited only weak antioxidant activities (28%) at 1.0 mg/ml.  相似文献   
60.
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