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21.
Rheological properties of low-moisture part-skim Mozarella cheese were evaluated as a function of storage time, test temperature, and deformation rate by uniaxial extension in a horizontal plane. Proteolysis of Mozzarella cheese caused marked decreases in the tensile strength and the deformability modulus, but not in the fracture strain. As the temperature increased from 10 to 40C, the fracture strain increased more than five-fold. The strength and the deformability modulus decreased about 60 and 85%, respectively, as the cheese temperature increased from 10 to 30C. The fracture strain of the cheese did not exhibit a clear trend with the deformation rate in the range of 50–500 mm/min. However, its strength and deformability modulus increased with the increasing deformation rate.  相似文献   
22.
The synthesis and characterisation of 2-tetradecylcyclobutanone (TCB) is described. Both 2-dodecykyclobutanone and TCB were shown to be present in liquid whole egg irradiated at doses of 2.5 and 10.0 kGy. These compounds were absent from the unirradiated pasteurised samples. Using gas chromatography and infrared spectroscopy, there was also evidence for the presence in irradiated egg of 2-tetradeccnyl- and 2-tetradecadienylyclobutanone which are formed from oleic and linoleic acids, respectively. Authentic standards for these unsaturated cyclobutanones were not available commercially but the presence of 2-tetra-decenylcyclobutanone was substantiated by hydrogenating the egg extracts so converting this unsaturated cyclobutanone to TCB. Saturated and unsaturated cyclobutanones appear to be specific products of irradiation and are potential markers for detection of irradiated liquid egg and probably other fat-containing foods.  相似文献   
23.
This paper develops the uniformly minimum variance unbiased estimator of the pointwise availability with type I censored data. The maximum likelihood estimator has also been highlighted.  相似文献   
24.
MOSFET substrate current model for circuit simulation   总被引:7,自引:0,他引:7  
A simple, accurate MOSFET substrate current model suitable for a circuit simulator is presented. The effect of substrate bias on substrate current is modeled without introducing additional parameters. The accuracy of this model is demonstrated by its ability to fit the experimental data for both standard and LDD devices with average errors of less than 6%. The new model is compared with the substrate current models reported in the literature. In addition, the temperature dependence of the substrate current in the range of 0-120°C is also modeled. The new model has been implemented in a circuit-level hot-electron reliability simulator, and the results obtained from simulation of an inverter circuit are presented  相似文献   
25.
Although a number of single current feedback op-amps (CFOA)-based single-resistance-controlled oscillators (SRCO) have appeared in earlier literature, only six of them are canonic (i.e., requiring only two capacitors and only three resistors). The object of this brief is to add to this list two new canonic single-CFOA-based SRCO configurations. An evaluation of these two new circuits has been carried out and their workability of has been confirmed by experimental results based upon AD844 CFOAs.  相似文献   
26.
Surface relief formed by nanoimprinting and etching into a thermally grown SiO2 layer on Si was used to position the initial nuclei formed by chemically vapor deposited Si and Ge. By controlling the deposition conditions, the surface diffusion length was adjusted to be comparable to or larger than the spacing between features, thus favoring nucleation adjacent to steps, rather than random nucleation. Random nucleation was further suppressed by a two-stage deposition process. Ge nucleation on oxide by chemical vapor deposition was enhanced by coating the oxide surface with an organic self-assembled monolayer (SAM) and by the nanoimprinted surface relief. The nanoimprinted surface relief also provides long-range order in the SAM.  相似文献   
27.
Two novel D–A–π–A metal free dyes with triphenylamine as donor, dithiophene-diketo-pyrrolo-pyrrole as acceptor unit, thiophene and phenyl π-conjugated bridges and a cyanoacetic acid as electron acceptor (TDPP1 and TDPP2 were denoted for thiophene and phenyl π-conjugated bridge, respectively) have been designed and used as sensitizers for DSSCs. Incorporation of dithiophene-diketo-pyrrolo-pyrrole, reduces the band gap significantly. The influence of π-conjugated bridge on optical and electrochemical properties were investigated. Results demonstrated that the absorption band of TDPP with thiophene π-conjugated bridge has red shifted due to the enhancement of electron donating ability of π-conjugated bridge. The DSSC based on TDPP1 shows prominent power conversion efficiency about 4.81%, which is higher that for TDPP2 (3.42%). The electrochemical impedance spectroscopy analysis reveal that the charge recombination resistance at the TiO2/dye/electrolyte interface for the DSSC based on TDPP1 is higher than that for TDPP2, which improves both Jsc and Voc. The PCE of the DSSC based on TDPP1 is further improved up to 6.34%, when deoxycholic acid (DCA) was employed as coadsorbant.  相似文献   
28.
A new definition of the fractional Laplace transform is proposed as a special case of the complex linear canonical transform. The proposed fractional Laplace transform reduces to the conventional bilateral Laplace transform and the fractional Fourier transform exactly and hence is better suited for the definition of the fractional Laplace transform as compared to the other definitions proposed earlier in the literature. The advantage of the proposed transform as compared to the conventional Laplace transform lies in providing a free parameter which can be effectively exploited in the filtering and signal separation problems.  相似文献   
29.

This paper proposes the design of three compact antennas for WiMAX, WLAN and ISM band applications. Antenna 1 consists of a monopole radiating element with an electromagnetic band gap (EBG) structured ground. By employing the EBG structure, an ultra-wide band frequency of 2.4–4.8 GHz (66.66%) is achieved. Antenna 2 is configured with an electric-LC (ELC) element, which achieved an ultra-wide band (UWB) frequency of 2.38–4.91 GHz (69.41%). Antenna 3 is integrated with ELC and EBG together, in which a UWB frequency of 2.3–5.3 GHz (78.94%) is obtained with improved impedance matching. The three antennas have omnidirectional radiation patterns which cover the ISM band at 2.4 GHz and WiMAX at 2.5/3.5 GHz over the operating bands. The radiation efficiency is?>?75% throughout the operating bands of all the antennas. In addition to the WiMAX and ISM bands, antenna 3 covers WLAN in the 5.2 GHz band. The proposed design can be applied to wireless mobile communication systems, which have the advantage of ease of fabrication and compactness.

  相似文献   
30.
A simple unsupervised MRF model based image segmentation approach   总被引:5,自引:0,他引:5  
A simple technique has been suggested to obtain optimal segmentation based on tonal and textural characteristics of an image using the Markov random field (MRF) model. The technique takes an initially over segmented image as well as the original image as its inputs and defines an MRF over the region adjacency graph (RAG) of the initially segmented regions. A tonal-region based segmentation technique due to Kartikeyan and Sarkar (1989) has been used for initial segmentation. The energy function has been defined over the first order cliques of the MRF. The essence of this approach is primarily based on quantitative values of the second order statistics, on region characteristics and consequently deciding upon the action of merging neighboring regions using the F-statistic. The effectiveness of our approach is demonstrated with wide variety of real life examples viz., indoor, outdoor and satellite and a comparison of its output with that of a previous work in the literature has been provided.  相似文献   
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