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1.
An ecofriendly and biodegradable porous structure was prepared from drying aqueous foams based on nano fibrillated cellulose (NFC), extracted from softwood pulp by subcritical water/CO2 treatment (SC-NFC). The primary aim of this work was to use the modified SC-NFC as stabilizer for a water-based Pickering emulsion which upon drying, yielded porous cellulosic materials, a good dye adsorbent. In order to exploit the carboxymethylated SC-NFC (CMSC-NFC, with a degree of substitution of 0.35 and a charge density of 649 μeqv/g) as a stabilizer for water-based Pickering emulsion in subsequent step, an optimized quantity of octyl amine (30 mg/g of SC-NFC) was added to make them partially hydrophobic. A series of dry foam structures were prepared by varying the concentrations of treated CMSC-NFCs and 4 wt% was found to be the optimum concentration to yield foam with high porosity (99%) and low density (0.038 g/cc) along with high compression strength (0.24 MPa), superior to the conventionally extracted NFC. The foams were applied to capture as high as 98% of methylene blue dyes, making them a potential green candidate for treating industrial effluent. In addition, the dye adsorption kinetics and isotherms were found to be well suited with second order kinetics and Langmuir isotherm models. 相似文献
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Chattopadhyay Arup Kumar Nag Amitava Singh Jyoti Prakash 《Multimedia Tools and Applications》2022,81(24):34969-34999
Multimedia Tools and Applications - A secret sharing scheme partitions a secret into a set of shares and distributes them among the eligible participants, with each participant receiving one share... 相似文献
4.
Wireless Personal Communications - In this paper, cooperative communication (CC) assisted cognitive wireless sensor network (CWSN) is presented for monitoring health and activity of an end-user in... 相似文献
5.
Mining high utility itemsets (HUIs) from transaction databases considers such factors as the unit profit and quantity of purchased items. Two-phase tree-based algorithms transform a database into compressed tree structures and generate candidate patterns through a recursive pattern-growth procedure. This procedure requires a lot of memory and time to construct conditional pattern trees. To address this issue, this study employs two compressed tree structures, namely, Utility Count Tree and String Utility Tree, to enumerate valid patterns and thus promote fast utility computation. Furthermore, the study presents an algorithm called single-phase utility computation (SPUC) that leverages these two tree structures to mine HUIs in a single phase by incorporating novel pruning strategies. Experiments conducted on both real and synthetic datasets demonstrate the superior performance of SPUC compared with IHUP, UP-Growth, and UP-Growth+ algorithms. 相似文献
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This paper presents the design criteria, procedure, and implementation of a soft-switched power-factor-correction (PFC) circuit based on the extended-period quasi-resonant (EPQR) principles. All power electronic devices including switches and diodes in the circuit are fully soft switched. The design method is demonstrated in a prototype circuit. The operating principles are confirmed with computer simulation and experimental results. A comparison of the EP-QR operation and zero-voltage-transition (ZVT) pulse-width modulation (PWM) method 相似文献
8.
U. Rambabu N. R. Munirathnam T. L. Prakash B. Vengalrao S. Buddhudu 《Journal of Materials Science》2007,42(22):9262-9266
High purity gallium oxide nanopowders have been synthesized by using a simple precipitation technique with calcination at
elevated temperature. From the X-ray pattern, the phase purity of the synthesized powders was confirmed as β-Ga2O3. Elemental quantification (stoichiometry) of Ga2O3 was also examined from the X-ray energy dispersive analysis (EDAX). Based on the recorded Fourier Transform Infrared (FTIR)
spectrum of Ga2O3, the IR bands due to Ga–O bond and crystal lattice vibrations have been identified in the wavenumber range 400–4,000 cm−1. From the measured SEM images, it is obvious to notice that the pH value has been playing a dominant role in obtaining morphologically
different gallium oxide nanopowders. Thermogravimetric analysis reveals 8.3% of weight loss when the sample was heated to
the temperature of 1,100 °C from the room temperature, which also shows a crystalline phase transformation. It is very interesting
to report that a broad blue emission at 455 nm has been measured from the synthesized gallium oxide nanopowders. 相似文献
9.
Ann Barrett Anuradha Prakash Deborah Sakelakos Irwin Taub Samuel Cohen Yuki Ohashi 《Food Hydrocolloids》1998,12(4):401-408
The effects of composition and thermal treatment on the water sorption and diffusional properties of idealized protein gels arranged in bilayer configurations were determined; these water binding/migration properties were related to the mechanical characteristics of the gels. Samples were prepared from whey protein concentrate (WPC), they consisted of water:WPC ratios of 1.5 to 5.67, and were thermally set for 20–60 min. Moisture migration rates from samples interfaced with filters were determined, as were moisture sorption capacities of samples immersed in water. The physical properties of the gels were assessed by uniaxial compression and microscopy. Results showed that gel strength and consequent extent of protein interaction—as affected by thermal treatment—controlled the ability of the gel structure to absorb water. Sorption was exponentially correlated with gel modulus and linearly correlated with a function of protein content, heating time, and immersion time. Rates of diffusion from interfaced gels were dependent solely on water content. It was concluded that the degree of protein interaction, whether influenced by concentration or thermal treatment, affected network extensibility and thus the capacity of the gels to act as receptors of moisture. Results have implications for the functionality of shelf-stable sandwiches and other multicomponent foods. 相似文献
10.