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991.
Gamma radiation inactivation of phytohemagglutinin (PHA) of red kidney bean in purified form as well as in seeds in different moisture conditions was demonstrated at different doses viz. 1, 10, 30, 50, 100 and 200 kGy. Irradiation of PHA in dry state (99.5% dry) or in 50% moisture condition showed structural intactness as studied by SDS–PAGE, size exclusion chromatography (SEC), fluorescence measurement, CD spectroscopy below 30 kGy, while a 50% reduction in hemagglutinin and mitogenic activity was observed in the dose range of 30–50 kGy. Radiation inactivation of purified PHA was more pronounced when irradiated in aqueous solution form resulting in complete destruction of secondary and tertiary structure as well as function at a dose of 10 kGy. Radiation processing of dry and soaked seeds of kidney bean exhibited 50% loss in functional activity of PHA at the doses of 50 and 30 kGy, respectively. Practicality of implication of the radiation processing for inactivation of this antinutrient in legume seeds is discussed. 相似文献
992.
Syngas production through gasification and cleanup for downstream applications — Recent developments
In the present paper various gasification technologies/gasifiers and syngas cleaning options are critically reviewed keeping in view various types of feedstocks and various downstream applications of syngas such as power generation, chemicals and hydrogen production, liquid fuels production and synthetic natural gas (SNG) production. Recent developments on gasification technologies including fixed bed dry bottom (FBDB) gasification, power high temperature Winkler (PHTW) gasification, catalytic steam gasification, transport reactor gasifier as well as syngas cleanup technique including hot gas filter and warm cleaning are discussed. Techno-economic analysis of various gasifiers as well as syngas cleaning processes along with the world scenario of syngas production and its various downstream applications is also discussed. 相似文献
993.
Combinatorial-designed multifunctional polymeric nanosystems for tumor-targeted therapeutic delivery
By definition, multifunctional nanosystems include several features within a single construct so that these devices can target tumors or other disease tissue, facilitate in vivo imaging, and deliver a therapeutic agent. Investigations of these nanosystems are rapidly progressing and provide new opportunities in the management of cancer. Tumor-targeted nanosystems are currently designed based primarily on the intrinsic physico-chemical properties of off-the-shelf polymers. Following fabrication, the surfaces of these nanoscale structures are functionalized for passive or active targeted delivery to the tumors. In this Account, we describe a novel approach for the construction of multifunctional polymeric nanosystems based on combinatorial design principles. Combinatorial approaches offer several advantages over conventional methods because they allow for the integration of multiple components with varied properties into a nanosystem via self-assembly or chemical conjugation. High-throughput synthesis and screening is required in polymer design because polymer composition directly affects properties including drug loading, retention in circulation, and targeting of the nanosystems. The first approach relies on the self-assembly of macromolecular building blocks with specific functionalities in aqueous media to yield a large variety of nanoparticle systems. These self-assembled nanosystems with diverse functionalities can then be rapidly screened in a high-throughput fashion for selection of ideal formulations, or hits, which are further evaluated for safety and efficacy. In another approach, a library of a large number of polymeric materials is synthesized using different monomers. Each of the formed polymers is screened for the selection of the best candidates for nanoparticle fabrication. The combinatorial design principles allow for the selection of those nanosystems with the most favorable properties based on the type of payload, route of administration, and the desired target for imaging and delivery. 相似文献
994.
We present a theoretical study of a solar photovoltaic-thermal (hybrid) system consisting of a flat-plate solar air heater mounted with solar cells and a plane booster. A conventional flat-plate collector is converted into a hybrid system by mounting solar cells directly on the absorber plate. A hybrid system is self-sufficient in the sense that the electrical energy required by the pump is supplied by the panel. Such systems are well suited to applications such as solar drying. The combined system is analysed for the case when the radiative and absorptive properties of the cell surface and the absorber plate are nearly the same. The solar cell efficiency is a linearly-decreasing function of the absorber plate temperature. The performance of the system has been evaluated for various combinations of boosters. The minimum area of the solar cells required to run the pump at a given flow rate has been calculated as a function of time, with and without boosters. The minimum cell area required decreases with the use of boosters. High cost cells may be replaced by low cost reflectors. The solar air heaters presently available on the market are not suitable for direct conversion to hybrid systems. 相似文献
995.
This study determines the glazing area in direct gain passive systems needed to ensure thermal comfort inside a building (room air temperature 20 ± 2°C). A 4 m × 4 m × 3 m single zone isolated house is analyzed in three different types of climates namely composite (8°C to 20°C, New Delhi), cold-cloudy (−2°C to 5°C, Srinagar), and cold-sunny (−14°C to −3°C, Leh). The analysis is based on the periodic solution of the heat conduction equations describing heat transmission in the building components, floor, walls, and roof, and the Fourier representation of the ambient temperature vnd the total solar radiation intercepted by the building envelope. Two types of construction are analyzed: the first type is a traditional construction with 22-cm-thick brick wall, plastered 15 mm on both the sides (U = 2.0 W m−2 K−1); and the second one is of the same type but with 10 cm of expanded polystyrene insulation on all the four walls and the roof (U = 0.31 W m−2 K−1). It is found that for traditional construction with U = 2.0 W m−2 K−1, the glazing U value has almost no effect on the room temperature even for large variation of the glazing area (10% to 40%, expressed in terms of percentage of floor area). For a well-insulated house (U = 0.31 W m−2 K−1), the glazing U value has no effect upon the room air temperature if the glazing area is small (less than 10%). The position of the insulation on the external surfaces is more effective in reducing large inroom air temperature. Finally, for an insulated house, we recommended glazing is 30%, 20%, and 10% for cold-sunny, cold-cloudy, and composite climates, respectively. 相似文献
996.
Ashish Garg Shailendra Kumar Gupta Jacek J. Jasieniak Th. Birendra Singh Scott E. Watkins 《Progress in Photovoltaics: Research and Applications》2015,23(8):989-996
We report on the use and stability of solution‐processed molybdenum oxide (sMoOx) thin films as anode‐modifying layers to replace conventionally used poly(3,4‐ethyldioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) layers in poly(3‐hexylthiophene):[6,6]‐phenyl C61 butyric acid methyl ester (P3HT/PC61BM) bulk heterojunction organic solar cells. Our results show that while as prepared devices using the two anode‐modifying layers possess similar performances, the sMoOx devices exhibit a staggering 20‐fold stability improvement in its performance half‐life compared with PEDOT/PSS devices, ~3400 h versus ~150 h, respectively. A further comparison of the stability between encapsulated and unencapsulated devices demonstrates the necessity for protection from atmospheric moisture and oxygen but again highlights the lucrative nature of sMoOx as a protective anode‐modifying layer compared with PEDOT/PSS even under ambient conditions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
S. K. Sharma T. K. Mandal C. Sharma Jagdish Chandra Kuniyal Ranjan Joshi Pitamber Prasad Dhyani Rohtash A. Sen H. Ghayas N. C. Gupta Priyanka Sharma M. Saxena A. Sharma B. C. Arya Arun Kumar 《Mapan》2014,29(4):243-253
Ambient trace gases (NH3, NO, NO2 and SO2) and black carbon (BC) were measured along with particulate matter (PM2.5) over the northwestern Himalayan region (Palampur, Kullu, Shimla, Solan and Nahan) of Himachal Pradesh (HP), India in a campaign mode during 12–22 March 2013 to evaluate the ambient air quality of the region. The average mixing ratio of ambient NH3, NO, NO2 and SO2 were recorded as 7.1 ± 2.6, 3.1 ± 1.3, 3.9 ± 1.4 and 1.7 ± 0.7 ppb respectively over the northwestern Himalayan region. The average concentration of BC was estimated as 2.2 ± 0.5 µg m?3 over the region whereas average concentration of PM2.5 mass was estimated as 41.8 ± 7.9 µg m?3. The spatial variation of ambient trace gases (NH3, NO, NO2 and SO2), BC and PM2.5 over the northwestern Himalayan region, India reveals that the region is mainly influenced by local activities, i.e., tourism activities, agricultural activities, biomass burning and vehicular emission. A significant positive linear correlation of NH3 and NH4 + with SO4 2?, NO3 ? and Cl? (NH4 + vs. SO4 2? , r 2 = 0.652; NH4 + vs. NO3 ?, r 2 = 0.701; and NH4 + vs. Cl?, r 2 = 0.627) of the PM2.5 indicates the possible formation of (NH4)2SO4, NH4NO3 and NH4Cl aerosols over the region. 相似文献
998.
999.
1000.
Wall admittances for circular and annular ring microstrip antennas have been determined, including the effect of the substrate. The magnetic current model is used and the analysis is carried out in Hankel transform domain. The final expressions for wall admittances are obtained in integral form. The contributions of the surface wave to the wall conductances have been determined by evaluating the integrals near the singularity using the singularity extraction technique. The radiation conductance has been determined by simple integration. The value of wall susceptance, obtained in this paper, agrees well with Kirchhoff's equivalent extension formula. A closed form expression for wall susceptance for theTM_{1n} mode has been obtained by curve fitting the numerical values. The effect of the substrate on wall admittance has been found to be significant for higher order modes and is shown to explain the measured input impedance of an annular ring microstrip antenna. 相似文献