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101.
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103.
Marisiddaiah Raju Sadineni Varakumar Rangaswamy Lakshminarayana Thirumalai Parthasarathy Krishnakantha Vallikannan Baskaran 《Food chemistry》2007,101(4):1598-1605
Carotenoid composition of green leafy vegetables (GLVs, n = 30) with medicinal value was analyzed by HPLC; vitamin A activity (as retinol equivalent, RE) of provitamin A carotenoids was calculated. Results show that among GLVs studied, the level of β-carotene (50–130 mg/100 g dry wt) was higher in nine GLVs than other carotenoids while lutein (50–187 mg/100 g dry wt) and zeaxanthin (1–5 mg/100 g dry wt) were higher in 12 GLVs than other xanthophylls. α-Carotene was detected only in nine GLVs, ranging from 1 to 37 mg/100 g dry wt. Interestingly, Chenopodium album, Commelina benghalensis and Solanum nigrum were found to contain higher levels of both lutein and β-carotene in the range of 84–187 and 50–115 mg/100 g dry wt, respectively. The values of retinol equivalents (RE) ranged from 641 to 19101 and were higher (>10,000) in six GLVs of the 30. The results demonstrate that GLVs studied contained higher levels of RE and lutein. 相似文献
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105.
Phosphate glasses in the compositions of 70P2O5–15Al2O3–14Na2O–1RE3+ (RE = Sm, Dy, and Tm) (mol%) were prepared by melt-quenching technique and characterized optically. The differential thermal analysis (DTA) profile of the host glass was carried out to confirm its thermal stability. For all the glasses absorption, photoluminescence and decay measurements have also been carried out. These glasses have shown strong emission and absorption bands in visible and near-infrared (NIR) region. From the measured absorption spectra, Judd–Ofelt (J–O) intensity parameters (Ω2, Ω4 and Ω6) have been calculated for all the studied ions. For Sm3+ doped glass, four emission bands centered at 562 nm (4G5/2 → 6H5/2), 598 nm (4G5/2 → 6H7/2), 644 nm (4G5/2 → 6H9/2), and 704 nm (4G5/2 → 6H11/2) have been observed with 402 nm (6H5/2 → 4F7/2) excitation wavelength. Of them, 598 nm (4G5/2 → 6H7/2) has shown a bright orange emission. With regard to Dy3+ doped glass, a blue emission band centered at 486 nm (4F9/2 → 6H15/2) and a bright yellow emission at 575 nm (4F9/2 → 6H13/2) have been observed, apart from 662 nm (4F9/2 → 6H11/2) emission transition with an excitation at 388 nm (6H15/2 → 4I13/2,4F7/2) wavelength. Emission bands of 650 nm (1G4 → 3F4) and 785 nm (1G4 → 3H5) transitions for the Tm3+ doped glass, with an excitation wavelength at 466 nm (3H6 → 1G4), have also been observed. The stimulated emission cross-sections of all the emission bands of RE3+ glasses (RE = Sm, Dy, and Tm) have been computed based on their measured full-width at half maximum (FWHM, Δλ) and measured lifetimes (τm). 相似文献
106.
107.
Khouri K.S. Lakshminarayana G. Jha N.K. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2005,13(5):513-524
This paper presents a memory binding algorithm for behaviors, used in application-specific integrated circuits (ASICs), that are characterized by the presence of conditionals and deeply nested loops that access memory extensively through arrays. Unlike previous works, this algorithm examines the effects of branch probabilities and allocation constraints. First, we demonstrate, through examples, the importance of incorporating branch probabilities and allocation constraint information when searching for a performance-efficient memory binding. We also show the interdependence of these two factors and how varying one without considering the other may greatly affect the performance of the behavior. Second, we introduce a memory binding algorithm that has the ability to examine numerous bindings by employing an efficient performance estimation procedure. The estimation procedure exploits locality of execution, which is an inherent characteristic of target behaviors. This enables the performance estimation technique to look at the global impact of the different bindings, given the allocation constraints. We tested our algorithm using a number of benchmarks from the parallel computing domain. A series of experiments demonstrates the algorithm's ability to produce bindings that optimize performance, meet memory allocation constraints, and adapt to different resource constraints and branch probabilities. One limitation of our algorithm is that, in its current form, it is not well suited for system-on-a-chip synthesis where there is complex communication between general-purpose microprocessors that use custom-designed arrays. Results show that the algorithm requires 41% fewer memories with a performance loss of only 0.2% when compared to a parallel memory architecture. When compared to the best of a series of random memory bindings, the algorithm improves schedule performance by 22%. 相似文献
108.
109.
P. Vijayalakshmi R. Subbarao G. Lakshminarayana 《Journal of the American Oil Chemists' Society》1988,65(6):939-941
A laboratory procedure was developed for hydrogenation of methyl esters of unsaturated fatty acids using decalin as a hydrogen-transfer
agent and 10% Pd/C as catalyst. The esters of 10-undecenoic, oleic, elaidic, stearolic, linoleic, cycloaliphatic C21 di-, C22 tri- and C36 dicarboxylic acids, and a mixture of hydrnocarpic, chaulmoogric and gorlic acids were hydrogenated. Chromatographic and spectral
analyses showed complete saturation. This procedure is simple, requiring no external source of hydrogen. 相似文献
110.
Lakshminarayana Mysore R. Hunsperger Robert G. Partain Larry D. 《Electronics letters》1978,14(19):640-641
GaAs lasers operating at room temperature are directly modulated at X-band frequencies. A fast silicon avalanche photodiode is used to demodulate the laser light. 相似文献