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91.
Gupta Isha Nayak Soumya Ranjan Gupta Sheifali Singh Swati Verma K.D. Gupta Abhishek Prakash Deo 《Multimedia Tools and Applications》2022,81(25):36309-36330
Multimedia Tools and Applications - Breast cancer is one of the widespread reasons of morbidity worldwide that begins in the cells of the tissues of morbidity worldwide in the woman community.... 相似文献
92.
Use of novel hydrogels based on modified cellulosics and methacrylamide for separation of metal ions from water systems 总被引:1,自引:0,他引:1
Interpenetrating networks (IPNs) based on extracted cellulose and its derivatives such as hydroxypropyl cellulose (HPC), cyanoethylcellulose, hydroxyethylcellulose, hydrazinodeoxycellulose, cellulosephosphate with methacrylamide (MAAm), and N,N‐methylene bisacrylamide were synthesized at reaction conditions evaluated for optimum network yield as a function of irradiation dose, concentrations of monomer and crosslinker, and amount of water. These networks were used in sorption of Fe2+, Cu2+, and Cr6+ ions. The networks were further functionlized by means of partial hydrolysis with 0.5N NaOH and metal ion sorption studies were carried out. Appreciable amount of all the three ions was sorbed and partial functionalization of the hydrogels results in selectivity in ion sorption with enhanced affinity for Fe2+ ions and total rejection of Cr6+ ions. These results are of interest for the development of low‐cost technologies based on smart hydrogels. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 667–671, 2002 相似文献
93.
Thermosensitive networks based on hydroxypropyl cellulose and N‐isopropylacrylamide crosslinked with N,N‐methylene bisacrylamide were synthesized by a simultaneous gamma radiation technique. The network yield was optimized by the variation of reaction parameters such as the total radiation dose, concentration of crosslinker and monomer, and amount of water. The hydrogels had a biphasic structure and good mechanical strength, even in the fully swollen state, and could be synthesized in any shape and size. Volume transitions as a function of time and temperature were studied for these hydrogels in water, and the effects on swelling in different media such as 0.5N NaOH, 0.5N HCl, and 5% NaCl at the optimum time and temperature were also studied. The response of the hydrogels to these diverse changes in the swelling media was observed, and the volume transitions due to environmental changes in the hydrogels were not sharp and discontinuous as a maximum volume collapse occurred at a temperature higher than the reported lower critical solution temperature of 32.5°C for N‐isopropylacrylamide. These hydrogels were environmentally sensitive and responded to changes in their thermal and ionic environment and have potential applications in diverse fields such as drug delivery, enzyme technology, and environmental management. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 479–488, 2004 相似文献
94.
ENGAGE compatibilized HDPE/EPDM blends: Modification of some industrially pertinent properties and morphology upon incorporation of Mg(OH)2 filler and electron beam crosslinked network 下载免费PDF全文
Bhuwanesh Kumar Sharma Subhendu Ray Chowdhury Atanu Jha Amit Kumar Samanta Prakash Mahanwar Kuppa Sivasankara Sarma 《应用聚合物科学杂志》2017,134(23)
To observe the effect of ENGAGE (a poly‐olefin elastomer) on compatibilization of industrially important incompatible blend, high‐density polyethylene (HDPE)/ethylene‐propylene diene elastomer (EPDM), 15 wt % ENGAGE is incorporated into the system and the latter is found satisfactorily efficient as compatibilizer for the above system. To improve some industrially pertinent properties another strategies are also followed in addition, incorporation of magnesium hydroxide [Mg(OH)2] and electron beam (EB) crosslinking into the system. The gel content was found to increase with radiation dose, EPDM content and Mg(OH)2 dispersion. ENGAGE interestingly increases the gel content that is, promotes crosslinking. It is unique that filler dispersion and crosslinked network formation maintain the compatibility of the ternary system, which is confirmed by X‐ray diffraction, differential scanning calorimetry, mechanical properties, and scanning electron microscope. The compatibilization, Mg(OH)2 dispersion, and EB crosslinking improve the mechanical, thermo mechanical, flame retardant properties, and phase morphology considerably. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44922. 相似文献
95.
Average self-diffusion coefficients of hydrated protons in sulfonated poly (ether sulfone) (SPES), Interpolymer and Nafion 117 membranes are measured by impedance spectroscopy and pulsed field gradient nuclear magnetic resonance (PFG NMR). Self-diffusion coefficient measured by impedance spectroscopy shows two patterns, one is at the low hydration states, i.e. λ = 2–4 and another at the high hydration states (starting from λ = 4). At lower hydration states the diffusion values increases slowly while steep increment is found at higher hydration level. PFG NMR shows similar trend throughout the measurements. The diffusion coefficients at higher temperatures are higher than at lower temperatures as a function of λ for SPES membrane. At the same value of λ, hydrated proton self-diffusion coefficient is found to be increased by 18% from 295.5 to 303 K. The thermo-mechanical properties of the membranes characterised by the means of DSC, TGA and DMA analysis show SPES, stable up to 450 °C and can be used for the high-temperature applications. 相似文献
96.
Ram Ramanathan Ertugrul Ciftcioglu Abhishek Samanta Rahul Urgaonkar Tom La Porta 《Wireless Networks》2017,23(4):1063-1083
We present a framework for non-asymptotic analysis of real-world multi-hop wireless networks that captures protocol overhead, congestion bottlenecks, traffic heterogeneity and other real-world concerns. The framework introduces the concept of symptotic scalability to determine the number of nodes to which a network scales, and a metric called change impact value for comparing the impact of underlying system parameters on network scalability. A key idea is to divide analysis into generic and specific parts connected via a signature—a set of governing parameters of a network scenario—such that analyzing a new network scenario reduces mainly to identifying its signature. Using this framework, we present the first closed-form symptotic scalability expressions for line, grid, clique, randomized grid and mobile topologies. We model both TDMA and 802.11, as well as unicast and broadcast traffic. We compare the analysis with discrete event simulations and show that the model provides sufficiently accurate estimates of scalability. We show how our impact analysis methodology can be used to progressively tune network features to meet a scaling requirement. We uncover several new insights, for instance, on the limited impact of reducing routing overhead, the differential nature of flooding traffic, and the effect real-world mobility on scalability. Our work is applicable to the design and deployment of real-world multi-hop wireless networks including community mesh networks, military networks, disaster relief networks and sensor networks. 相似文献
97.
This paper analyzes the backward incidence of stronger pollution control into factors of production using a two-sector general equilibrium model in which the economy experiences perfect capital mobility but norigid factor price differential. In this context we conclude that higher levels of wage and capital rental differentials may act as an effective control over the pollution emission in the economy when factor price differentials directly depend on the pollution level. 相似文献
98.
An investigation was carried out to modify the toughness of triethylene tetramine cured DGEBA (diglycidyl ether of bisphenol-A) resin using solid amine terminated poly (ethylene glycol) benzoate (ATPEGB) as modifier with and without red mud waste particles. The solid ATPEGB modifier synthesized from the acid catalyzed esterification reaction of poly (ethylene glycol) (PEG) and 4-amino benzoic acid was characterized by Fourier transform infrared spectroscopy (FT-IR) and ^1H-NMR (nuclear magnetic resonance) spectroscopies, viscosity measurements, and solubility parameter calculation. The unfilled and red mud waste filled modified epoxy networks were evaluated with impact, adhesive, tensile, flexural and thermal properties by differential scanning calorimetry (DSC), thermogravimetric (TG) and dynamic mechanical analysis (DMA). The effect of modifier concentration and red mud waste particles on toughening behavior was also investigated. The optimum properties were obtained at 12.5 phr (parts per hundred parts of resin) concentration of the modifier. The ATPEGB modified cured epoxy was thermally stable up to 315℃. The morphology on fracture surfaces of cured epoxy was also analyzed by scanning electron microscopy (SEM). 相似文献
99.
Sujata Swain Sk. Muneer A. R. Sahu A. Mahapatra R. R. Negi B. Samanta 《Integrated ferroelectrics》2020,205(1):186-193
AbstractIn the present work, the effect of high-energy ball milling (HEBM) of starting precursors of hydroxyapatite (Ca10(PO4)6(OH)2)/HA system on the processing temperature, morphological, mechanical, and electrical properties are highlighted. Calcination and sintering of HA system were carried out in microwave furnace. XRD study confirmed the evolution of HA phase and EDX analysis confirmed Ca/P ratio ~1.65. Grain size of HA samples, synthesized by using microwave-assisted HEBM technique was found to be in the order of 54–75?nm. Enhanced dielectric and mechanical properties were obtained in HA samples. 相似文献
100.
Surface ultrastructure of gills in relation to the feeding ecology of an angler catfish Chaca chaca (Siluriformes,Chacidae) 下载免费PDF全文
Arup Mistri Neeraj Verma Usha Kumari Swati Mittal Ajay Kumar Mittal 《Microscopy research and technique》2016,79(10):973-981
Surface ultrastructure of the gills of the angler catfish Chaca chaca was investigated to unravel the adaptive modifications associated with the feeding ecology of the fish. The fish is often found in mud or in soft substrates where they remain buried both for protection and to feed. Gill rakers present on the gill arch in most fish species are absent in this fish. The absence of gill rakers are associated with the feeding habit of the fish and is considered to facilitate the swallowing of captured prey smoothly without any hindrance. Highly corrugated surface of the gill arch and gill filaments could be associated to retain water/mucus to prevent dessicassion of the fish. Papillae like epithelial protuberances each bearing a taste bud at its summit toward the pharyngeal side of the gill arch is associated with the sorting of the food. Large number of mucous goblet cells on the gill arch epithelium are considered to secret copious mucus to lubricate the prey for easy swallowing. In C. chaca the gill septa between gill filaments are reduced. This could enhance the flexibility and permit the free movement of the gill filaments. Extensive secondary lamellae and infrequent mucous goblet cells on secondary lamellae are associated to increase the surface area to enhance efficiency of gaseous exchange. 相似文献