9 results on '"Priyanka R. Sharma"'
Search Results
2. Morphology and Flow Behavior of Cellulose Nanofibers Dispersed in Glycols
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Chengbo Zhan, Jiahui Chen, Shirish Chodankar, Benjamin S. Hsiao, Tomas Rosén, Ruifu Wang, Sunil K. Sharma, Priyanka R. Sharma, and Tianbo Liu
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Nanocomposite ,Materials science ,Morphology (linguistics) ,Polymers and Plastics ,Organic Chemistry ,Flow (psychology) ,food and beverages ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Scientific method ,Nanofiber ,Materials Chemistry ,Cellulose ,0210 nano-technology - Abstract
Understanding the morphology and flow behavior of cellulose nanofibers (CNFs) dispersed in organic solvents can improve the process of fabricating new cellulose-based nanocomposites. In this study,...
- Published
- 2019
3. Efficient Removal of Arsenic Using Zinc Oxide Nanocrystal-Decorated Regenerated Microfibrillated Cellulose Scaffolds
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Priyanka R. Sharma, Sunil K. Sharma, Benjamin S. Hsiao, and Richard Antoine
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Materials science ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Zinc ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallinity ,chemistry ,Nanocrystal ,Environmental Chemistry ,Thermal stability ,Cellulose ,0210 nano-technology ,Phosphoric acid ,Arsenic ,Wurtzite crystal structure ,Nuclear chemistry - Abstract
Regenerated microfibrillated cellulose (R-MFC) fibers were prepared successfully by a combined dissolution and regeneration approach using phosphoric acid/ethanol treatment on jute cellulose. The prepared R-MFC fibers possessed high surface area (10.74 m2/g), good aspect ratio (L/D = 30), and excellent thermal stability (Tmax = 352 °C). In addition, the fibers exhibited 3.84 wt % of phosphate groups (PO42–) with a ζ-potential of −8.4 mV and low crystallinity index (CI) of 47.5%. These R-MFC fibers were in the cellulose II polymorph, confirmed by 13C CPMAS NMR and WAXD measurements, and they were effective to anchor the growth of ZnO nanocrystals. WAXD and TEM examinations on the imbedded ZnO nanocrystals indicated that they possessed the hexagonal wurtzite crystal structure and could assemble into a flower-like morphology in the R-MFC scaffold. A R-MFC composite containing 41 wt % of ZnO nanocrystals was found to be very efficient to remove arsenic (As(V)) ions from water with the maximum capacity of 4,42...
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- 2019
4. Sustainable nanocellulose membranes for PEM fuel cells
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Miriam Rafailovich, Priyanka R. Sharma, Sunil K. Sharma, Likun Wang, Aniket Raut, Songze Wu, Songtao Li, and George Cai
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- 2020
5. High Aspect Ratio Carboxycellulose Nanofibers Prepared by Nitro-Oxidation Method and Their Nanopaper Properties
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Sunil K. Sharma, Priyanka R. Sharma, Bingqian Zheng, Ruifu Wang, Chengbo Zhan, Surita R. Bhatia, and Benjamin S. Hsiao
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Aqueous solution ,Materials science ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Shear rate ,Crystallinity ,chemistry.chemical_compound ,Rheology ,chemistry ,Chemical engineering ,Nanofiber ,General Materials Science ,Fiber ,Carboxylate ,0210 nano-technology ,Suspension (vehicle) - Abstract
High aspect ratio carboxycellulose nanofibers (NOCNF), having typical length over 1000 nm, width ∼4.6 nm, thickness ∼1.3 nm, and carboxylate content of 0.42 mmol/g, were extracted from jute fibers using a modified nitro-oxidation method. The extracted nanofiber was found to possess crystallinity of 69% (measured by wide-angle X-ray diffraction, WAXD), relatively higher than that of raw jute fibers (crystallinity ∼61%). Gelation of NOCNF in aqueous suspensions was observed due to the high aspect ratio of the fiber even at a relatively low concentration. Rheological studies on the NOCNF suspensions at different concentrations (0.01–1 wt %) revealed the shear-thinning behavior with increasing shear rate. The corresponding viscoelastic moduli (G′ and G′′) results indicated that the NOCNF suspension at concentration between 0.1 and 0.2 wt % possessed a liquid–gel transition. The rheological data near the gelation point could be fitted by the Winter–Chambon model, where the results confirmed the formation of a ...
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- 2018
6. Understanding the Mechanistic Behavior of Highly Charged Cellulose Nanofibers in Aqueous Systems
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Benjamin S. Hsiao, Chengbo Zhan, Xiangfang Peng, L. Daniel Söderberg, Nitesh Mittal, Priyanka R. Sharma, Lihong Geng, and Farhan Ansari
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Flocculation ,Aqueous solution ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Charge density ,02 engineering and technology ,Dynamic mechanical analysis ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,Viscosity ,Rheology ,Chemical engineering ,Nanofiber ,Materials Chemistry ,0210 nano-technology ,Suspension (vehicle) - Abstract
Mechanistic behavior and flow properties of cellulose nanofibers (CNFs) in aqueous systems can be described by the crowding factor and the concept of contact points, which are functions of the aspect ratio and concentration of CNF in the suspension. In this study, CNFs with a range of aspect ratio and surface charge density (380–1360 μmol/g) were used to demonstrate this methodology. It was shown that the critical networking point of the CNF suspension, determined by rheological measurements, was consistent with the gel crowding factor, which was 16. Correlated to the crowding factor, both viscosity and modulus of the systems were found to decrease by increasing the charge density of CNF, which also affected the flocculation behavior. Interestingly, an anomalous rheological behavior was observed near the overlap concentration (0.05 wt %) of CNF, at which the crowding factor was below the gel crowding factor, and the storage modulus (G′) decreased dramatically at a given frequency threshold. This behavior ...
- Published
- 2018
7. Nanocellulose from Spinifex as an Effective Adsorbent to Remove Cadmium(II) from Water
- Author
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Aurnov Chattopadhyay, Nasim Amiralian, Benjamin S. Hsiao, Priyanka R. Sharma, Sunil K. Sharma, Lihong Geng, and Darren J. Martin
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Cadmium ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Mineralization (biology) ,0104 chemical sciences ,Nanocellulose ,chemistry.chemical_compound ,Crystallinity ,Adsorption ,chemistry ,Nitric acid ,Environmental Chemistry ,Carboxylate ,0210 nano-technology ,Sodium nitrite ,Nuclear chemistry - Abstract
Nanocelluloses, in the form of carboxycellulose nanofibers, with low crystallinity (CI ∼ 50%), high surface charge (−68 mV), and hydrophilicity (static contact angle 38°), were prepared from an untreated (raw) Australian spinifex grass using a nitro-oxidation method employing nitric acid and sodium nitrite. The resulting nanofibers (NOCNF) were found to be an effective medium to remove Cd2+ ions (cadmium(II)) from water. For example, a low concentration of NOCNF suspension (0.20 wt %) could remove Cd2+ ions over a large concentration range (50–5000 ppm) in a relatively short time period (≤5 min). The results showed that at low Cd2+ concentrations (below 500 ppm), the remediation mechanism was dominated by interactions between carboxylate groups on the NOCNF surface and Cd2+ ions, which also acted as a cross-linking agent to gel the NOCNF suspension. At high Cd2+ concentrations (above 1000 ppm), the remediation mechanism was dominated by the mineralization process of forming Cd(OH)2 nanocrystals, which was...
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- 2018
8. Efficient Removal of UO22+ from Water Using Carboxycellulose Nanofibers Prepared by the Nitro-Oxidation Method
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Benjamin S. Hsiao, Aurnov Chattopadhyay, Sunil K. Sharma, and Priyanka R. Sharma
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Scanning electron microscope ,General Chemical Engineering ,Inorganic chemistry ,Energy-dispersive X-ray spectroscopy ,Langmuir adsorption model ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Industrial and Manufacturing Engineering ,0104 chemical sciences ,chemistry.chemical_compound ,symbols.namesake ,Adsorption ,chemistry ,Nitric acid ,symbols ,Carboxylate ,Uranyl hydroxide ,0210 nano-technology ,Acrylic acid - Abstract
Carboxycellulose nanofibers (NOCNF) were extracted from untreated jute fibers using a simple nitro-oxidation method, employing nitric acid and sodium nitrite. The resulting NOCNF possessed high surface charge (−70 mV) and large carboxylate content (1.15 mmol/g), allowing them to be used as an effective medium to remove UO22+ ions from water. The UO22+ (or U(VI)) removal mechanism was found to include two stages: the initial stage of ionic adsorption on the NOCNF surface following by the later stage of uranyl hydroxide mineralization, as evidenced by the Fourier transform infrared, scanning electron microscopy with energy dispersive spectroscopy capabilities, transmission electron miscroscopy, and wide-angle X-ray diffraction results. Using the Langmuir isotherm model, the extracted NOCNF exhibited a very high maximum adsorption capacity (1470 mg/g), about several times higher than the most efficient adsorbent reported (poly(acrylic acid) hydrogel). It was also found that the remediation of UO22+ ions by N...
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- 2017
9. Chemical and Pathogenic Cleanup of Wastewater Using Surface-Functionalized CeO2 Nanoparticles
- Author
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Savita Chaudhary, Rajeev Kumar, Diksha Singh, Priyanka R. Sharma, and Ahmad Umar
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Cerium oxide ,Aqueous solution ,Renewable Energy, Sustainability and the Environment ,Chemistry ,General Chemical Engineering ,Inorganic chemistry ,Nanoparticle ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010501 environmental sciences ,021001 nanoscience & nanotechnology ,01 natural sciences ,Oxygen ,Adsorption ,Chemical engineering ,Wastewater ,Environmental Chemistry ,Surface modification ,Turbidity ,0210 nano-technology ,0105 earth and related environmental sciences - Abstract
In this paper, we report the simple synthesis, detailed characterization, and total wastewater cleanup by adsorption using bare and surfactant-functionalized cerium oxide (CeO2) nanoparticles. The synthesis of CeO2 nanoparticles was performed by a facile aqueous solution process and characterized by a diverse range of techniques, which confirmed that the nanoparticles are well-crystalline, possessing good structural and optical properties. The competence of the prepared nanoparticles was further explored to determine the dye removal efficiency. The developed nanoparticles have also provided chlorine-free disinfection of water. The observed results revealed that the synthesized nanoparticles efficiently lower the pollutant concentrations, reduced turbidity, and exhibited significant reductions in total dissolved solids, chemical and biochemical oxygen demands, and pathogenic load. Interestingly, the surfactant-functionalized nanoparticles revealed that they possess the ability to remove approximately 99% o...
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- 2017
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