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81.
Impact of gamma irradiation on the antinutritional constituents of seeds of Mucuna pruriens was assessed on exposing to doses of 2.5, 5.0, 7.5, 10, 15 and 30 kGy. Except for 2.5 kGy, the rest showed significant dose-dependent increase in phenolics. Tannin concentration did not differ significantly up to 7.5 kGy, while it significantly increased at higher doses. Excluding 2.5 kGy, the rest of the treatments showed significant decreases in the phytic acid and complete degradation was attained at 15 and 30 kGy. The l-DOPA concentration showed a dose-dependent decline. A trace amount of hemagglutination activity was seen on human erythrocytes in raw seeds, which was completely absent on irradiation (>5 kGy). Concentration of Polonium-210, a natural radionuclide falls within the admissible limits for consumption. As Mucuna seeds serve as food, feed or as pharmaceuticals, it may be necessary to set the ionizing radiation to a specific dose to retain optimum levels or to eliminate phenolics, tannins, phytic acid and L-DOPA. As irradiation is a physical and cold process, it may be ideal and emerge as an important technique to improve the nutritional or pharmaceutical quality of Mucuna seeds and its products. 相似文献
82.
Ramanath N. Bhat Rajiv Kumar 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,48(4):453-466
The feasibility of synthesising pure zeolite beta in high yields using silica gel as the source of SiO2 is demonstrated. The phase-purity and yield of beta is enhanced by using silica gels with high surface area. The influence of various synthesis parameters (Si/Al ratio, alkalinity, dilution level, concentration of the organic base, etc.) on the kinetics of synthesis as well as the quality and yield of the zeolite have been investigated. A correlation between XRD crystallinity of the samples with varying degrees of crystallinity and that estimated from framework IR spectroscopy, differential thermal analysis and adsorption of n-hexane is demonstrated. The dependence of the yield of zeolite beta on SiO2/Al2O3 ratio of the gel is also reported. The results of the present study indicate the feasibility of a cheaper route for the manufacture of zeolite beta. 相似文献
83.
Bezier surface/surface intersection 总被引:2,自引:0,他引:2
The computational requirements and accuracy of two methods for finding the intersection of Bezier surfaces are examined. In both methods, the existence of an intersection curve is confirmed by using the convex hull property of such surfaces. The first method evaluates the intersection by recursive subdivision of two patches with overlapping hulls. The second method detects a point on the intersection curve and then incrementally traces the intersection in the parametric spaces of the two surfaces. With both methods, the intersection of a pair of first-order planar patches must be solved analytically. The intersection is approximated by first-order Bezier patches in the first case and by planar triangles in the second. Overall, the method of incremental tracing is shown to give more accurate results than the method of recursive subdivision 相似文献
84.
JAIN protocol APIs 总被引:3,自引:0,他引:3
JAIN envisions the creation of a number of Java APIs that abstract the details of networks and protocol implementations, and allow for the development of portable applications. The JAIN Protocol Experts Group (PEG) will focus on developing Java APIs for protocols used in telephony, INs, wireless networks, and the Internet. The PEG is organized into an SS7 subgroup and an IP subgroup. The article provides an introduction to PEG. It next describes the JAIN SS7 APIs. It then describes the JAIN IP APIs. The article also explains how JAIN SS7 and IP APIs can be leveraged for the converged SS7-IP networks of the future and describes the JAIN PEG roadmap 相似文献
85.
N. Recham V.V. Bhat M. Kandavel L. Aymard J.-M. Tarascon A. Rougier 《Journal of Alloys and Compounds》2008,464(1-2):377-382
Enhanced sorption properties of ball-milled MgH2 are reported by adding NbF5. Among various catalyst amounts, 2 mol% of NbF5 reveals to be the optimum concentration leading to significant reduction of the desorption temperature as well as faster kinetics of ball-milled MgH2. At 200 °C, temperature at which MgH2 does not show any activity, MgH2NbF5/2 mol% composite desorbs 3.2 wt.% of H2 in 50 mins. Interestingly, the addition of NbF5 is also associated with an increase in the desorption pressure. At 300 °C, MgH2NbF5/2 mol% composite starts to desorb hydrogen at 600 mbar in comparison with 1 mbar for MgH2. Further improvements were successfully achieved by pre-grinding NbF5 prior to ball-milling the catalyst with MgH2. Such pre-ground NbF5 catalyzed MgH2 composite desorbs 3 wt.% of H2 at 150 °C. Improved properties are associated with smaller activation energies down to values close to the enthalpy of formation of MgH2. Finally, the mechanism at the origin of the enhancement is discussed in terms of catalyst stability, MgF2 formation and electronic density localization. 相似文献
86.
The substrate temperature achieved during physical vapor deposition significantly affects the properties and phases of thin films. An Isoflux ICM-10 Dual Target Inverted Cylindrical Magnetron Sputtering system is used to deposit low temperature alpha-phase alumina, for which an experimentally determined substrate temperature is desired. Constraints inherent to the Isoflux system limit the use of a thermocouple. Instead, a pressure vessel containing numerous samples of temperature indicating liquids is placed in the chamber during operation. These indicator paints are observed upon completion of the deposition process to record the substrate temperature. Measurements indicate a temperature range of 343 °C to 399 °C for our alpha-phase alumina films deposited at a pressure of 0.27 Pa (2 mTorr), a substrate bias of − 35 V, and a power of 5 kW. Theoretical heat transfer calculations support the experimental measurements. A parametric investigation showed that the removal of the − 35 V substrate bias decreases the substrate temperatures by approximately 35 °C and that the substrate temperature increases about 50 °C for each additional kilowatt of power in the range of 1 kW to 6 kW. 相似文献
87.
Favourable conditions for the growth of good quality silicon carbide (SiC) whiskers from rice husk have been discussed in
the light of available evidence on the probable growth mechanism and the theoretical understanding of the same. Preliminary
results indicate an increase in whisker yield at lower temperatures and coarsening of whiskers with longer duration of conversion. 相似文献
88.
We demonstrate the first integration of active electronic devices with semiconductor waveguide modulators. By combining ion-implanted GaAs MESFET amplifiers with directional-coupler electro-optic modulators, the DC drive voltage has been reduced by a factor of ?v = 9, making an effective electro-optic figure-of-merit ?vn3r41 for GaAs superior to that of LiNbO3 相似文献
89.
W.K. Chan J.H. Abeles K.C. Nguyen R. Bhat M.A. Koza 《Photonics Technology Letters, IEEE》1989,1(3):65-67
Optical taps are key elements for optical signal processing. The authors demonstrate the high-speed operation of an InGaAs p-i-n photodetector on InP waveguides. For a 300- mu m-long tap that samples 19% of the light propagating in a 7- mu m-wide waveguide, the response time is 50 ps at a 1 V reverse bias. The taps require a simple epitaxial growth and can readily be integrated with electrooptic modulators and other optoelectronic devices for multigigahertz optical signal processing.<> 相似文献
90.
Telecommunication Systems - Internet of Things (IoT) has changed the way people live by transforming everything into smart systems. Wireless Sensor Network (WSN) forms an important part of IoT.... 相似文献