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81.
A proper node architecture design capable to support different network protocol enhances the data transport capability of a wavelength division multiplexed system. In the present paper a simple node architecture model has been developed to simulate the node throughput based on media access control protocols for bursty data traffic of variable time slot duration and data rate. An appropriate mathematical model has been derived to evaluate different types of traffic reservation protocols used in WDM networks. It has been observed that the network performance is well controlled through implemented protocols and network design parameters. 相似文献
82.
Minerals and heavy metal concentrations of 23 plants (arial parts, leaves, bark, stem, root, rhizome, dried berries, seeds)
possessing health-promoting effects and used in indigenous medicines (as medicinal food) were determined using inductively
coupled plasma atomic spectrometry. Vital essential minerals and heavy metals were present in all the samples analyzed. The
majority of the plant materials were rich in some of the essential minerals like Na, K, Ca, Fe, Mg, Cu, Mn, and Zn, which
are known to be beneficial for health. The plant material of Vitiveria zizinalis had highest concentration of toxic heavy metals, including arsenic (53.1 mg/100 g), chromium (6.74 mg/100 g), cobalt (10.2 mg/100 g),
mercury (3.6 mg/100 g), and nickel (3.28 mg/100 g). Results of the present study provide vital data on the availability of
some essential minerals, which can be useful to provide dietary information for designing value-added foods and for food biofortification.
Apart from this, data on the contaminant levels of heavy metals highlights the necessity on the quality and safety concerns
about their use. 相似文献
83.
A local market survey of fresh, raw coriander leaves, which is a component of many ready-to-eat, Indian dishes showed large variation in their bacterial load (7.0×106–1.36×108 cfu/gm) and mold and fungi (3.0×103–1.0×104 cfu/gm) and presence of potentially pathogenic bacteria such as faecal coliforms, Listeria and Yersinia. Conventional chlorination treatment affected the structural integrity of leaves leading to enhancement of rotting. Exposure to a low dose of 1 kGy was efficient for bacterial decontamination and elimination of potential pathogens without affecting the keeping quality of coriander leaves upto two weeks storage at 8–10 °C, measured visually in terms of degree of yellowing and rotting. Irradiation at higher doses led to the increased rotting during storage. The total chlorophyll contents as well its components, chlorophyll a and b did not change significantly on irradiation and subsequent storage. Similarly, the total carotenoid levels remained unaffected by exposure to 1 kGy dose, however, a dose dependent enhancement in their extractability was observed in irradiated leaves. No qualitative differences were observed in the GLC profile of volatile oils of control and irradiated (1 kGy) samples. There were no significant quantitative changes in the constituents of the major aroma compounds obtained from these two samples. Effects of irradiation on storage of the seasoning were also assessed. 相似文献
84.
High oxygen permeability with optimal selectivity of the membrane is required for advancement in air separation membrane technology. Zeolite 4A-PDMS composite membranes were prepared by incorporation of Zeolite 4A nanoscale crystals during the polymerization process of PDMS membrane using toluene and n-heptane solvents, and their oxygen gas permeability and selectivity were explored. Small angle neutron scattering (SANS) technique was further used to study the polymer chain conformation and structure of membranes influenced by Zeolite 4A loading. The intersegmental distance between polymer chains and polymer chain aggregation or clustering were found to be increased on increasing the Zeolite 4A content in the membranes. Increment in the O2 permeability and O2/N2 selectivity were observed for both type of membranes (toluene and n-heptane) with 1 wt% Zeolite 4A loading. The best performance result with O2/N2 selectivity of 2.6, and O2 permeability of 1052 Barrer was exhibited by PDMS/toluene membrane loaded with 1 wt% Zeolite 4A. The PDMS/toluene membranes with 10 wt% Zeolite 4A loading exhibited increased O2 permeability of 1245 Barrer with a fair O2/N2selectivity of ~1.7, while the PDMS/n-heptane membrane with the same loading exhibited excellent O2 permeability of 6773 Barrer but lesser O2/N2 selectivity of ~1.2. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48047. 相似文献
85.
Shanti Kiran Nayak Angelica D. Benavidez Fernando H. Garzon 《Journal of the American Ceramic Society》2019,102(6):3738-3744
Molybdenum carbide has immense potential as an active catalyst for reaction systems such as synthesis of important chemicals like ammonia. However, the carbide is not used as a commercial catalyst or support as the current synthesis processes produce low surface area material or have contaminants such as excess carbon and surface and chemisorbed oxygen. Moreover, attempts to refine the synthesis pathways are usually not supported by any thermochemical modeling. In this study, a facile and reproducible method to synthesize high surface area molybdenum carbide was developed with the help of thermochemical modeling to better understand molybdenum-carbon phase behavior. We have synthesized 2-5 nm particles of MoxC with surface areas of up to 360 m2/g as characterized using a variety of techniques including X-ray diffraction and electron microscopy. 相似文献
86.
Prajapati Pragyanand Singh Akhilesh Kumar 《Journal of Materials Science: Materials in Electronics》2022,33(5):2550-2565
Journal of Materials Science: Materials in Electronics - Tuning the band gap of ferroelectric materials to visible region without reducing the polarization can provide an ideal photovoltaic... 相似文献
87.
A 2-dimensional electrostatic potential modeling of fully depleted channel, with high-k based dual work function double gate (DWFDG) MOSFET, has been devel 相似文献
88.
89.
As the world moves toward more green and efficient means of modes of transport, electric vehicles are the most suitable and ideal choice to fulfill this requirement. Rapid developments in the field of battery technology are the main reason for their progress, but thermal management in such systems has been an area of concern for a long time. The work undertaken is to design and develop a battery management system (BMS) with a specific focus on the thermal behavior of the battery pack with varying vehicle loads as well as environmental conditions. To design an efficient BMS, one needs to model the battery behavior covering the thermal as well as electrical aspects of the battery. Apart from the battery model, a mathematical model of the electrical vehicle to mimic the various road load conditions for battery also needs to be modeled. Depending on the need for cooling based on battery behavior, the cooling circuit is modeled for the battery pack used. The entire study has been carried out using Dymola, a mathematical modeling software. 相似文献
90.
The present work focused on the comparative analysis of organic Rankine cycle (ORC) operated with nanoparticles. The effect of CuO and Al2O 3 nanoparticles synthesized with water and circulated within heat exchangers are examined. Thermal efficiency and levelized energy cost (LEC) of the nanofluid based ORC are evaluated simultaneously in the present work. The optimization problem of ORC is formed and solved using heat transfer search algorithm. Operating parameters of the nanofluid based ORC such as pinch point temperature difference of heat exchangers, evaporation pressure, the mass flow rate of refrigerant, and concentration of nanoparticles are investigated in the optimization study. Further, the effect of turbine ratio, heat source temperature, and mass flow rate of heat source fluid on CuO and Al 2O 3 based ORC is explored and discussed. It was observed that a total variation of 35.2% was obtained at the cost of 3.5% variation in LEC between extreme design points. The maximum thermal efficiency of 19.3% and 19.32% can be obtained with CuO and Al 2O 3 with 2.616 and 2.62 $/kWh, respectively. Comparative results reveal that CuO based ORC shows dominance in terms of economic performance over Al 2O 3 based ORC for any given value of the thermal efficiency. 相似文献